Department of Biology, Chemistry, Pharmacy

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Peer-reviewed journal articles

2023

[189]

K. Puls, and G. Wolber. Solving an Old Puzzle: Elucidation and Evaluation of the Binding Mode of Salvinorin A at the Kappa Opioid Receptor, Molecules, 28(2):, 2023.
Links: [doi:10.3390/molecules28020718] [show BibTeX] [show abstract]  x  @article{RN331, author = {Puls, Kristina and Wolber, Gerhard}, title = {Solving an Old Puzzle: Elucidation and Evaluation of the Binding Mode of Salvinorin A at the Kappa Opioid Receptor}, journal = {Molecules}, volume = {28}, number = {2}, abstract = {The natural product Salvinorin A (SalA) was the first nitrogen-lacking agonist discovered for the opioid receptors and exhibits high selectivity for the kappa opioid receptor (KOR) turning SalA into a promising analgesic to overcome the current opioid crisis. Since SalA’s suffers from poor pharmacokinetic properties, particularly the absence of gastrointestinal bioavailability, fast metabolic inactivation, and subsequent short duration of action, the rational design of new tailored analogs with improved clinical usability is highly desired. Despite being known for decades, the binding mode of SalA within the KOR remains elusive as several conflicting binding modes of SalA were proposed hindering the rational design of new analgesics. In this study, we rationally determined the binding mode of SalA to the active state KOR by in silico experiments (docking, molecular dynamics simulations, dynophores) in the context of all available mutagenesis studies and structure-activity relationship (SAR) data. To the best of our knowledge, this is the first comprehensive evaluation of SalA’s binding mode since the determination of the active state KOR crystal structure. SalA binds above the morphinan binding site with its furan pointing toward the intracellular core while the C2-acetoxy group is oriented toward the extracellular loop 2 (ECL2). SalA is solely stabilized within the binding pocket by hydrogen bonds (C210ECL2, Y3127.35, Y3137.36) and hydrophobic contacts (V1182.63, I1393.33, I2946.55, I3167.39). With the disruption of this interaction pattern or the establishment of additional interactions within the binding site, we were able to rationalize the experimental data for selected analogs. We surmise the C2-substituent interactions as important for SalA and its analogs to be experimentally active, albeit with moderate frequency within MD simulations of SalA. We further identified the non-conserved residues 2.63, 7.35, and 7.36 responsible for the KOR subtype selectivity of SalA. We are confident that the elucidation of the SalA binding mode will promote the understanding of KOR activation and facilitate the development of novel analgesics that are urgently needed.}, ISSN = {1420-3049}, DOI = {10.3390/molecules28020718}, year = {2023}, type = {Journal Article} }  x  Solving an Old Puzzle: Elucidation and Evaluation of the Binding Mode of Salvinorin A at the Kappa Opioid Receptor

The natural product Salvinorin A (SalA) was the first nitrogen-lacking agonist discovered for the opioid receptors and exhibits high selectivity for the kappa opioid receptor (KOR) turning SalA into a promising analgesic to overcome the current opioid crisis. Since SalA’s suffers from poor pharmacokinetic properties, particularly the absence of gastrointestinal bioavailability, fast metabolic inactivation, and subsequent short duration of action, the rational design of new tailored analogs with improved clinical usability is highly desired. Despite being known for decades, the binding mode of SalA within the KOR remains elusive as several conflicting binding modes of SalA were proposed hindering the rational design of new analgesics. In this study, we rationally determined the binding mode of SalA to the active state KOR by in silico experiments (docking, molecular dynamics simulations, dynophores) in the context of all available mutagenesis studies and structure-activity relationship (SAR) data. To the best of our knowledge, this is the first comprehensive evaluation of SalA’s binding mode since the determination of the active state KOR crystal structure. SalA binds above the morphinan binding site with its furan pointing toward the intracellular core while the C2-acetoxy group is oriented toward the extracellular loop 2 (ECL2). SalA is solely stabilized within the binding pocket by hydrogen bonds (C210ECL2, Y3127.35, Y3137.36) and hydrophobic contacts (V1182.63, I1393.33, I2946.55, I3167.39). With the disruption of this interaction pattern or the establishment of additional interactions within the binding site, we were able to rationalize the experimental data for selected analogs. We surmise the C2-substituent interactions as important for SalA and its analogs to be experimentally active, albeit with moderate frequency within MD simulations of SalA. We further identified the non-conserved residues 2.63, 7.35, and 7.36 responsible for the KOR subtype selectivity of SalA. We are confident that the elucidation of the SalA binding mode will promote the understanding of KOR activation and facilitate the development of novel analgesics that are urgently needed.

[188]

Y. Shi, C. A. Wolf, R. Lotfy, S. S. Sharma, A. F. Tesfa, G. Wolber, M. Bureik, and B. R. Clark. Deciphering the biotransformation mechanism of dialkylresorcinols by CYP4F11, Bioorg Chem, 131:106330, 2023.
Links: [doi:10.1016/j.bioorg.2022.106330] [show BibTeX] [show abstract]  x  @article{RN330, author = {Shi, Yue and Wolf, Clemens A. and Lotfy, Rowaa and Sharma, Sangeeta S. and Tesfa, Abel Fekadu and Wolber, Gerhard and Bureik, Matthias and Clark, Benjamin R.}, title = {Deciphering the biotransformation mechanism of dialkylresorcinols by CYP4F11}, journal = {Bioorganic Chemistry}, volume = {131}, pages = {106330}, abstract = {Cytochrome P450 enzymes (CYPs) are one of the most important classes of oxidative enzymes in the human body, carrying out metabolism of various exogenous and endogenous substrates. In order to expand the knowledge of these enzymes’ specificity and to obtain new natural product derivatives, CYP4F11, a cytochrome P450 monooxygenase, was used in the biotransformation of dialkylresorcinols 1 and 2, a pair of antibiotic microbial natural products. This investigation resulted in four biotransformation products including two oxidative products: a hydroxylated derivative (3) and a carboxylic acid derivative (4). In addition, acetylated (5) and esterified products (6) were isolated, formed by further metabolism by endogenous yeast enzymes. Oxidative transformations were highly regioselective, and took place exclusively at the ω-position of the C-5 alkyl chain. Homology modeling studies revealed that optimal hydrogen bonding between 2 and the enzyme can only be established with the C-5 alkyl chain pointing towards the heme. The closely-related CYP4F12 was not capable of oxidizing the dialkylresorcinol 2. Modeling experiments rationalize these differences by the different shapes of the binding pockets with respect to the non-oxidized alkyl chain. Antimicrobial testing indicated that the presence of polar groups on the side-chains reduces the antibiotic activity of the dialkylresorcinols.}, keywords = {Cytochrome P450 Homology modeling Biotransformation Natural products Dialkylresorcinols Fission yeast Recombinant expression}, ISSN = {0045-2068}, DOI = {10.1016/j.bioorg.2022.106330}, url = {https://www.sciencedirect.com/science/article/pii/S0045206822007374}, year = {2023}, type = {Journal Article} }  x  Deciphering the biotransformation mechanism of dialkylresorcinols by CYP4F11

Cytochrome P450 enzymes (CYPs) are one of the most important classes of oxidative enzymes in the human body, carrying out metabolism of various exogenous and endogenous substrates. In order to expand the knowledge of these enzymes’ specificity and to obtain new natural product derivatives, CYP4F11, a cytochrome P450 monooxygenase, was used in the biotransformation of dialkylresorcinols 1 and 2, a pair of antibiotic microbial natural products. This investigation resulted in four biotransformation products including two oxidative products: a hydroxylated derivative (3) and a carboxylic acid derivative (4). In addition, acetylated (5) and esterified products (6) were isolated, formed by further metabolism by endogenous yeast enzymes. Oxidative transformations were highly regioselective, and took place exclusively at the ω-position of the C-5 alkyl chain. Homology modeling studies revealed that optimal hydrogen bonding between 2 and the enzyme can only be established with the C-5 alkyl chain pointing towards the heme. The closely-related CYP4F12 was not capable of oxidizing the dialkylresorcinol 2. Modeling experiments rationalize these differences by the different shapes of the binding pockets with respect to the non-oxidized alkyl chain. Antimicrobial testing indicated that the presence of polar groups on the side-chains reduces the antibiotic activity of the dialkylresorcinols.

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2022

[187]

D. Akman, K. Denzinger, S. Huang, J. T. Lee, J. W. Nafie, G. Wolber, G. W. Zamponi, D. W. Armstrong, and M. G. Gunduz. Focusing on C-4 position of Hantzsch 1,4-dihydropyridines: Molecular modifications, enantioseparation, and binding mechanism to L- and T-type calcium channels, Eur J Med Chem, :114787, 2022.
Links: [doi:10.1016/j.ejmech.2022.114787] [show BibTeX] [show abstract]  x  @article{RN323, author = {Akman, Dilara and Denzinger, Katrin and Huang, Sun and Lee, J. T. and Nafie, Jordan W. and Wolber, Gerhard and Zamponi, Gerald W. and Armstrong, Daniel W. and Gunduz, Miyase Gozde}, title = {Focusing on C-4 position of Hantzsch 1,4-dihydropyridines: Molecular modifications, enantioseparation, and binding mechanism to L- and T-type calcium channels}, journal = {European Journal of Medicinal Chemistry}, pages = {114787}, abstract = {1,4-Dihydropyridines (DHPs) represent the blockbuster class of L-type calcium channel blockers that have tremendous therapeutic value against cardiovascular conditions. Due to their abilities to additionally target other subtypes of calcium channels, DHPs are also considered promising molecules for the treatment of neurological and psychiatric disorders. Having been in the market for more than forty years, DHP is one of the most modified scaffolds for the development of novel molecules acting on calcium channels. Taking the chemical structures of approved DHPs into account, it is noteworthy that C-4 position is the least modified part of the ring system. Therefore, in the present study, we focused on this location and carried out various molecular modifications to obtain twelve potential calcium channel blockers with a DHP-based hexahydroquinoline scaffold (DA1-DA12). The whole-cell patch clamp technique applied to analyze the blocking ability of the synthesized compounds on both L- (Cav1.2) and T- (Cav3.2) type calcium channels revealed five blockers with different selectivity profiles. Introducing naphthyl moiety onto the C-4 position of the main scaffold led to the identification of a selective blocker of Cav1.2 (DA8). The benzodioxole-substituted derivative (DA1) was the most potent and selective Cav3.2 inhibitor, therefore, its enantiomers were separated using HPLC on a chiral stationary phase. Retesting single isomers on Cav3.2 revealed that S-enantiomer was mainly responsible for the block. Finally, DA compounds were docked into two generated homology models of L- and T-type calcium channels. Molecular dynamics (MD) simulations and 3D pharmacophore modeling provided further insights into the detailed binding mechanism of DHPs to Cav1.2 as well as to Cav3.2.}, keywords = {Hantzsch synthesis Hexahydroquinoline Chiral center Patch clamp Molecular dynamics 3D pharmacophore}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2022.114787}, url = {https://www.sciencedirect.com/science/article/pii/S0223523422006894}, year = {2022}, type = {Journal Article} }  x  Focusing on C-4 position of Hantzsch 1,4-dihydropyridines: Molecular modifications, enantioseparation, and binding mechanism to L- and T-type calcium channels

1,4-Dihydropyridines (DHPs) represent the blockbuster class of L-type calcium channel blockers that have tremendous therapeutic value against cardiovascular conditions. Due to their abilities to additionally target other subtypes of calcium channels, DHPs are also considered promising molecules for the treatment of neurological and psychiatric disorders. Having been in the market for more than forty years, DHP is one of the most modified scaffolds for the development of novel molecules acting on calcium channels. Taking the chemical structures of approved DHPs into account, it is noteworthy that C-4 position is the least modified part of the ring system. Therefore, in the present study, we focused on this location and carried out various molecular modifications to obtain twelve potential calcium channel blockers with a DHP-based hexahydroquinoline scaffold (DA1-DA12). The whole-cell patch clamp technique applied to analyze the blocking ability of the synthesized compounds on both L- (Cav1.2) and T- (Cav3.2) type calcium channels revealed five blockers with different selectivity profiles. Introducing naphthyl moiety onto the C-4 position of the main scaffold led to the identification of a selective blocker of Cav1.2 (DA8). The benzodioxole-substituted derivative (DA1) was the most potent and selective Cav3.2 inhibitor, therefore, its enantiomers were separated using HPLC on a chiral stationary phase. Retesting single isomers on Cav3.2 revealed that S-enantiomer was mainly responsible for the block. Finally, DA compounds were docked into two generated homology models of L- and T-type calcium channels. Molecular dynamics (MD) simulations and 3D pharmacophore modeling provided further insights into the detailed binding mechanism of DHPs to Cav1.2 as well as to Cav3.2.

[186]

S. El Deeb, A. E. Ibrahim, A. Al-Harrasi, G. Wolber, and R. Gust. Validated capillary zone electrophoresis method for impurity profiling and determination of niII(3-ome-salophene), Separations, 9(2):25, 2022.
Links: [doi:10.3390/separations9020025] [show BibTeX] [show abstract]  x  @article{RN317, author = {El Deeb, Sami and Ibrahim, Adel Ehab and Al-Harrasi, Ahmed and Wolber, Gerhard and Gust, Ronald}, title = {Validated capillary zone electrophoresis method for impurity profiling and determination of niII(3-ome-salophene)}, journal = {Separations}, volume = {9}, number = {2}, pages = {25}, abstract = {A capillary zone electrophoresis method was developed for the determination of NiII(3-OMe-salophene), a substance with anticancer activity in vitro. A fused silica capillary (56 cm × 100 µm) was used for this purpose. The method was optimized in terms of parameters affecting the electrophoretic conditions in order to optimize separation efficiency and total time of migration. The analysis was best performed using an operating buffer of 50 mM borate, adjusted to pH 9.3, mixed with acetonitrile (50%, v/v) as organic modifier. Injections were performed hydrodynamically by applying a pressure of 50 mbar for 8 s, and a 30 kV separation voltage was selected at 25 ◦C. Detection was carried out at 250 nm using diode array detector (DAD). The method allowed the separation of NiII(3-OMe-salophene) from four other structurally related impurities in a total migration time (tm) of 8 min. Peak identification was achieved using the standard reference of individual impurities. The purity of the migrated NiII(3-OMe-salophene) was confirmed by Ultra-violet (UV) scan overlay depending on DAD. The linear ranges for the determination of NiII(3-OMe-salophene) was 400–20,000 ng mL−1 with limit of detection (LOD) of 120 ng mL−1. Acceptable intra-day and inter-day precisions were achieved (%relative standard deviation (RSD) results were less than 0.76% and 0.30%, respectively). The proposed method was assessed for greenness and compared to reported methodologies to prove superiority.}, ISSN = {2297-8739}, DOI = {10.3390/separations9020025}, year = {2022}, type = {Journal Article} }  x  Validated capillary zone electrophoresis method for impurity profiling and determination of niII(3-ome-salophene)

A capillary zone electrophoresis method was developed for the determination of NiII(3-OMe-salophene), a substance with anticancer activity in vitro. A fused silica capillary (56 cm × 100 µm) was used for this purpose. The method was optimized in terms of parameters affecting the electrophoretic conditions in order to optimize separation efficiency and total time of migration. The analysis was best performed using an operating buffer of 50 mM borate, adjusted to pH 9.3, mixed with acetonitrile (50%, v/v) as organic modifier. Injections were performed hydrodynamically by applying a pressure of 50 mbar for 8 s, and a 30 kV separation voltage was selected at 25 ◦C. Detection was carried out at 250 nm using diode array detector (DAD). The method allowed the separation of NiII(3-OMe-salophene) from four other structurally related impurities in a total migration time (tm) of 8 min. Peak identification was achieved using the standard reference of individual impurities. The purity of the migrated NiII(3-OMe-salophene) was confirmed by Ultra-violet (UV) scan overlay depending on DAD. The linear ranges for the determination of NiII(3-OMe-salophene) was 400–20,000 ng mL−1 with limit of detection (LOD) of 120 ng mL−1. Acceptable intra-day and inter-day precisions were achieved (%relative standard deviation (RSD) results were less than 0.76% and 0.30%, respectively). The proposed method was assessed for greenness and compared to reported methodologies to prove superiority.

[185]

Y. Lu, X. Liu, R. Lotfy, S. Liu, A. F. Tesfa, G. Wolber, M. Bureik, and B. R. Clark. Experimental and computational studies on the biotransformation of pseudopyronines with human Cytochrome P450 CYP4F2, J Nat Prod, :, 2022.
Links: [doi:10.1021/acs.jnatprod.2c00616] [show BibTeX] [show abstract]  x  @article{RN326, author = {Lu, Ya and Liu, Xueling and Lotfy, Rowaa and Liu, Sijie and Tesfa, Abel Fekadu and Wolber, Gerhard and Bureik, Matthias and Clark, Benjamin R.}, title = {Experimental and computational studies on the biotransformation of pseudopyronines with human Cytochrome P450 CYP4F2}, journal = {Journal of Natural Products}, note = {doi: 10.1021/acs.jnatprod.2c00616}, abstract = {The secondary metabolite pseudopyronine B, isolated from Pseudomonas mosselii P33, was biotransformed by human P450 enzymes, heterologously expressed in the fission yeast Schizosaccharomyces pombe. Small-scale studies confirmed that both CYP4F2 and CYP4F3A were capable of oxidizing the substrate, with the former achieving a higher yield. In larger-scale studies using CYP4F2, three new oxidation products were obtained, the structures of which were elucidated by UV–vis, 1D and 2D NMR, and HR-MS spectroscopy. These corresponded to hydroxylated, carboxylated, and ester derivatives (1–3) of pseudopyronine B, all of which had been oxidized exclusively at the ω-position of the C-6 alkyl chain. In silico homology modeling experiments highlighted key interactions between oxygen atoms of the pyrone ring and two serine residues and a histidine residue of CYP4F2, which hold the substrate in a suitable orientation for oxidation at the terminus of the C-6 alkyl chain. Additional modeling studies with all three pseudopyronines revealed that the seven-carbon alkyl chain of pseudopyronine B was the perfect length for oxidation, with the terminal carbon lying close to the heme iron. The antibacterial activity of the substrates and three oxidation products was also assessed, revealing that oxidation at the ω-position removes all antimicrobial activity. This study both increases the range of known substrates for human CYF4F2 and CYP4F3A enzymes and demonstrates their utility in producing additional natural product derivatives.}, ISSN = {0163-3864}, DOI = {10.1021/acs.jnatprod.2c00616}, url = {https://doi.org/10.1021/acs.jnatprod.2c00616}, year = {2022}, type = {Journal Article} }  x  Experimental and computational studies on the biotransformation of pseudopyronines with human Cytochrome P450 CYP4F2

The secondary metabolite pseudopyronine B, isolated from Pseudomonas mosselii P33, was biotransformed by human P450 enzymes, heterologously expressed in the fission yeast Schizosaccharomyces pombe. Small-scale studies confirmed that both CYP4F2 and CYP4F3A were capable of oxidizing the substrate, with the former achieving a higher yield. In larger-scale studies using CYP4F2, three new oxidation products were obtained, the structures of which were elucidated by UV–vis, 1D and 2D NMR, and HR-MS spectroscopy. These corresponded to hydroxylated, carboxylated, and ester derivatives (1–3) of pseudopyronine B, all of which had been oxidized exclusively at the ω-position of the C-6 alkyl chain. In silico homology modeling experiments highlighted key interactions between oxygen atoms of the pyrone ring and two serine residues and a histidine residue of CYP4F2, which hold the substrate in a suitable orientation for oxidation at the terminus of the C-6 alkyl chain. Additional modeling studies with all three pseudopyronines revealed that the seven-carbon alkyl chain of pseudopyronine B was the perfect length for oxidation, with the terminal carbon lying close to the heme iron. The antibacterial activity of the substrates and three oxidation products was also assessed, revealing that oxidation at the ω-position removes all antimicrobial activity. This study both increases the range of known substrates for human CYF4F2 and CYP4F3A enzymes and demonstrates their utility in producing additional natural product derivatives.

[184]

T. Noonan, K. Denzinger, V. Talagayev, Y. Chen, K. Puls, C. A. Wolf, S. Liu, T. N. Nguyen, and G. Wolber. Mind the gap - deciphering GPCR pharmacology using 3D pharmacophores and artificial intelligence, Pharmaceuticals, 15(11):1304, 2022.
Links: [doi:10.3390/ph15111304] [show BibTeX] [show abstract]  x  @article{RN327, author = {Noonan, Theresa and Denzinger, Katrin and Talagayev, Valerij and Chen, Yu and Puls, Kristina and Wolf, Clemens Alexander and Liu, Sijie and Nguyen, Trung Ngoc and Wolber, Gerhard}, title = {Mind the gap - deciphering GPCR pharmacology using 3D pharmacophores and artificial intelligence}, journal = {Pharmaceuticals}, volume = {15}, number = {11}, pages = {1304}, abstract = {G protein-coupled receptors (GPCRs) are amongst the most pharmaceutically relevant and well-studied protein targets, yet unanswered questions in the field leave significant gaps in our understanding of their nuanced structure and function. Three-dimensional pharmacophore models are powerful computational tools in in silico drug discovery, presenting myriad opportunities for the integration of GPCR structural biology and cheminformatics. This review highlights success stories in the application of 3D pharmacophore modeling to de novo drug design, the discovery of biased and allosteric ligands, scaffold hopping, QSAR analysis, hit-to-lead optimization, GPCR de-orphanization, mechanistic understanding of GPCR pharmacology and the elucidation of ligand–receptor interactions. Furthermore, advances in the incorporation of dynamics and machine learning are highlighted. The review will analyze challenges in the field of GPCR drug discovery, detailing how 3D pharmacophore modeling can be used to address them. Finally, we will present opportunities afforded by 3D pharmacophore modeling in the advancement of our understanding and targeting of GPCRs}, ISSN = {1424-8247}, DOI = {10.3390/ph15111304}, url = {https://www.mdpi.com/1424-8247/15/11/1304}, year = {2022}, type = {Journal Article} }  x  Mind the gap - deciphering GPCR pharmacology using 3D pharmacophores and artificial intelligence

G protein-coupled receptors (GPCRs) are amongst the most pharmaceutically relevant and well-studied protein targets, yet unanswered questions in the field leave significant gaps in our understanding of their nuanced structure and function. Three-dimensional pharmacophore models are powerful computational tools in in silico drug discovery, presenting myriad opportunities for the integration of GPCR structural biology and cheminformatics. This review highlights success stories in the application of 3D pharmacophore modeling to de novo drug design, the discovery of biased and allosteric ligands, scaffold hopping, QSAR analysis, hit-to-lead optimization, GPCR de-orphanization, mechanistic understanding of GPCR pharmacology and the elucidation of ligand–receptor interactions. Furthermore, advances in the incorporation of dynamics and machine learning are highlighted. The review will analyze challenges in the field of GPCR drug discovery, detailing how 3D pharmacophore modeling can be used to address them. Finally, we will present opportunities afforded by 3D pharmacophore modeling in the advancement of our understanding and targeting of GPCRs

[183]

K. Puls, A. Olivé-Marti, S. Pach, B. Pinter, F. Erli, G. Wolber, and M. Spetea. In vitro, in vivo and In silico characterization of a novel kappa-opioid receptor antagonist, Pharmaceuticals, 15(6):680, 2022.
Links: [doi:10.3390/ph15060680] [show BibTeX] [show abstract]  x  @article{RN320, author = {Puls, Kristina and Olivé-Marti, Aina-Leonor and Pach, Szymon and Pinter, Birgit and Erli, Filippo and Wolber, Gerhard and Spetea, Mariana}, title = {In vitro, in vivo and In silico characterization of a novel kappa-opioid receptor antagonist}, journal = {Pharmaceuticals}, volume = {15}, number = {6}, pages = {680}, abstract = {Kappa-opioid receptor (KOR) antagonists are promising innovative therapeutics for the treatment of the central nervous system (CNS) disorders. The new scaffold opioid ligand, Compound A, was originally found as a mu-opioid receptor (MOR) antagonist but its binding/selectivity and activation profile at the KOR and delta-opioid receptor (DOR) remain elusive. In this study, we present an in vitro, in vivo and in silico characterization of Compound A by revealing this ligand as a KOR antagonist in vitro and in vivo. In the radioligand competitive binding assay, Compound A bound at the human KOR, albeit with moderate affinity, but with increased affinity than to the human MOR and without specific binding at the human DOR, thus displaying a preferential KOR selectivity profile. Following subcutaneous administration in mice, Compound A effectively reverse the antinociceptive effects of the prototypical KOR agonist, U50,488. In silico investigations were carried out to assess the structural determinants responsible for opioid receptor subtype selectivity of Compound A. Molecular docking, molecular dynamics simulations and dynamic pharmacophore (dynophore) generation revealed differences in the stabilization of the chlorophenyl moiety of Compound A within the opioid receptor binding pockets, rationalizing the experimentally determined binding affinity values. This new chemotype bears the potential for favorable ADMET properties and holds promise for chemical optimization toward the development of potential therapeutics. View Full-Text}, ISSN = {1424-8247}, DOI = {10.3390/ph15060680}, url = {https://www.mdpi.com/1424-8247/15/6/680}, year = {2022}, type = {Journal Article} }  x  In vitro, in vivo and In silico characterization of a novel kappa-opioid receptor antagonist

Kappa-opioid receptor (KOR) antagonists are promising innovative therapeutics for the treatment of the central nervous system (CNS) disorders. The new scaffold opioid ligand, Compound A, was originally found as a mu-opioid receptor (MOR) antagonist but its binding/selectivity and activation profile at the KOR and delta-opioid receptor (DOR) remain elusive. In this study, we present an in vitro, in vivo and in silico characterization of Compound A by revealing this ligand as a KOR antagonist in vitro and in vivo. In the radioligand competitive binding assay, Compound A bound at the human KOR, albeit with moderate affinity, but with increased affinity than to the human MOR and without specific binding at the human DOR, thus displaying a preferential KOR selectivity profile. Following subcutaneous administration in mice, Compound A effectively reverse the antinociceptive effects of the prototypical KOR agonist, U50,488. In silico investigations were carried out to assess the structural determinants responsible for opioid receptor subtype selectivity of Compound A. Molecular docking, molecular dynamics simulations and dynamic pharmacophore (dynophore) generation revealed differences in the stabilization of the chlorophenyl moiety of Compound A within the opioid receptor binding pockets, rationalizing the experimentally determined binding affinity values. This new chemotype bears the potential for favorable ADMET properties and holds promise for chemical optimization toward the development of potential therapeutics. View Full-Text

[182]

K. Puls, H. Schmidhammer, G. Wolber, and M. Spetea. Mechanistic characterization of the pharmacological profile of hs-731, a peripherally acting opioid analgesic, at the µ-, δ, κ-opioid and nociceptin receptors, Molecules, 27(3):919, 2022.
Links: [doi:10.3390/molecules27030919] [show BibTeX] [show abstract]  x  @article{RN318, author = {Puls, Kristina and Schmidhammer, Helmut and Wolber, Gerhard and Spetea, Mariana}, title = {Mechanistic characterization of the pharmacological profile of hs-731, a peripherally acting opioid analgesic, at the µ-, δ, κ-opioid and nociceptin receptors}, journal = {Molecules}, volume = {27}, number = {3}, pages = {919}, abstract = {Accumulated preclinical and clinical data show that peripheral restricted opioids provide pain relief with reduced side effects. The peripherally acting opioid analgesic HS-731 is a potent dual μ-/δ-opioid receptor (MOR/DOR) full agonist, and a weak, partial agonist at the κ-opioid receptor (KOR). However, its binding mode at the opioid receptors remains elusive. Here, we present a comprehensive in silico evaluation of HS-731 binding at all opioid receptors. We provide insights into dynamic interaction patterns explaining the different binding and activity of HS-731 on the opioid receptors. For this purpose, we conducted docking, performed molecular dynamics (MD) simulations and generated dynamic pharmacophores (dynophores). Our results highlight two residues important for HS-731 recognition at the classical opioid receptors (MOR, DOR and KOR), particular the conserved residue 5.39 (K) and the non-conserved residue 6.58 (MOR: K, DOR: W and KOR: E). Furthermore, we assume a salt bridge between the transmembrane helices (TM) 5 and 6 via K2275.39 and E2976.58 to be responsible for the partial agonism of HS-731 at the KOR. Additionally, we experimentally demonstrated the absence of affinity of HS-731 to the nociceptin/orphanin FQ peptide (NOP) receptor. We consider the morphinan phenol Y1303.33 responsible for this affinity lack. Y1303.33 points deep into the NOP receptor binding pocket preventing HS-731 binding to the orthosteric binding pocket. These findings provide significant structural insights into HS-731 interaction pattern with the opioid receptors that are important for understanding the pharmacology of this peripheral opioid analgesic.}, keywords = {GPCR opioid receptor HS-731 peripheral opioid agonist analgesia binding selectivity molecular docking molecular dynamics simulations}, ISSN = {1420-3049}, DOI = {10.3390/molecules27030919}, year = {2022}, type = {Journal Article} }  x  Mechanistic characterization of the pharmacological profile of hs-731, a peripherally acting opioid analgesic, at the µ-, δ, κ-opioid and nociceptin receptors

Accumulated preclinical and clinical data show that peripheral restricted opioids provide pain relief with reduced side effects. The peripherally acting opioid analgesic HS-731 is a potent dual μ-/δ-opioid receptor (MOR/DOR) full agonist, and a weak, partial agonist at the κ-opioid receptor (KOR). However, its binding mode at the opioid receptors remains elusive. Here, we present a comprehensive in silico evaluation of HS-731 binding at all opioid receptors. We provide insights into dynamic interaction patterns explaining the different binding and activity of HS-731 on the opioid receptors. For this purpose, we conducted docking, performed molecular dynamics (MD) simulations and generated dynamic pharmacophores (dynophores). Our results highlight two residues important for HS-731 recognition at the classical opioid receptors (MOR, DOR and KOR), particular the conserved residue 5.39 (K) and the non-conserved residue 6.58 (MOR: K, DOR: W and KOR: E). Furthermore, we assume a salt bridge between the transmembrane helices (TM) 5 and 6 via K2275.39 and E2976.58 to be responsible for the partial agonism of HS-731 at the KOR. Additionally, we experimentally demonstrated the absence of affinity of HS-731 to the nociceptin/orphanin FQ peptide (NOP) receptor. We consider the morphinan phenol Y1303.33 responsible for this affinity lack. Y1303.33 points deep into the NOP receptor binding pocket preventing HS-731 binding to the orthosteric binding pocket. These findings provide significant structural insights into HS-731 interaction pattern with the opioid receptors that are important for understanding the pharmacology of this peripheral opioid analgesic.

[181]

D. Stepanov, D. Buchmann, N. Schultze, G. Wolber, K. Schaufler, S. Guenther, and V. Belik. A combined bayesian and similarity-based approach for predicting E. coli biofilm inhibition by phenolic natural compounds, J Nat Prod, :, 2022.
Links: [doi:10.1021/acs.jnatprod.2c00005] [show BibTeX] [show abstract]  x  @article{RN322, author = {Stepanov, Dmitri and Buchmann, David and Schultze, Nadin and Wolber, Gerhard and Schaufler, Katharina and Guenther, Sebastian and Belik, Vitaly}, title = {A combined bayesian and similarity-based approach for predicting E. coli biofilm inhibition by phenolic natural compounds}, journal = {Journal of Natural Products}, note = {doi: 10.1021/acs.jnatprod.2c00005}, abstract = {Screening for biofilm inhibition by purified natural compounds is difficult due to compounds’ chemical diversity and limited commercial availability, combined with time- and cost-intensiveness of the laboratory process. In silico prediction of chemical and biological properties of molecules is a widely used technique when experimental data availability is of concern. At the same time, the performance of predictive models directly depends on the amount and quality of experimental data. Driven by the interest in developing a model for prediction of the antibiofilm effect of phenolic natural compounds such as flavonoids, we performed experimental assessment of antibiofilm activity of 320 compounds from this subset of chemicals. The assay was performed once on two Escherichia coli strains on agar in 24-well microtiter plates. The inhibition was assessed visually by detecting morphological changes in macrocolonies. Using the data obtained, we subsequently trained a Bayesian logistic regression model for prediction of biofilm inhibition, which was combined with a similarity-based method in order to increase the overall sensitivity (at the cost of accuracy). The quality of the predictions was subsequently validated by experimental assessment in three independent experiments with two resistant E. coli strains of 23 compounds absent in the initial data set. The validation demonstrated that the model may successfully predict the targeted effect as compared to the baseline accuracy. Using a randomly selected database of commercially available natural phenolics, we obtained approximately 6.0% of active compounds, whereas using our prediction-based substance selection, the percentage of phenolics found to be active increased to 34.8%.}, ISSN = {0163-3864}, DOI = {10.1021/acs.jnatprod.2c00005}, url = {https://doi.org/10.1021/acs.jnatprod.2c00005}, year = {2022}, type = {Journal Article} }  x  A combined bayesian and similarity-based approach for predicting E. coli biofilm inhibition by phenolic natural compounds

Screening for biofilm inhibition by purified natural compounds is difficult due to compounds’ chemical diversity and limited commercial availability, combined with time- and cost-intensiveness of the laboratory process. In silico prediction of chemical and biological properties of molecules is a widely used technique when experimental data availability is of concern. At the same time, the performance of predictive models directly depends on the amount and quality of experimental data. Driven by the interest in developing a model for prediction of the antibiofilm effect of phenolic natural compounds such as flavonoids, we performed experimental assessment of antibiofilm activity of 320 compounds from this subset of chemicals. The assay was performed once on two Escherichia coli strains on agar in 24-well microtiter plates. The inhibition was assessed visually by detecting morphological changes in macrocolonies. Using the data obtained, we subsequently trained a Bayesian logistic regression model for prediction of biofilm inhibition, which was combined with a similarity-based method in order to increase the overall sensitivity (at the cost of accuracy). The quality of the predictions was subsequently validated by experimental assessment in three independent experiments with two resistant E. coli strains of 23 compounds absent in the initial data set. The validation demonstrated that the model may successfully predict the targeted effect as compared to the baseline accuracy. Using a randomly selected database of commercially available natural phenolics, we obtained approximately 6.0% of active compounds, whereas using our prediction-based substance selection, the percentage of phenolics found to be active increased to 34.8%.

[180]

D. Thieme, P. Anielski, S. Rzeppa, C. A. Wolf, G. Wolber, and A. M. Keiler. Detection of 18-methyl steroids: Case report on a forensic urine sample and corresponding dietary supplements, Drug Testing and Analysis, 14(11-12):1864-1870, 2022.
Links: [doi:10.1002/dta.3389] [show BibTeX] [show abstract]  x  @article{RN325, author = {Thieme, Detlef and Anielski, Patricia and Rzeppa, Sebastian and Wolf, Clemens A. and Wolber, Gerhard and Keiler, Annekathrin M.}, title = {Detection of 18-methyl steroids: Case report on a forensic urine sample and corresponding dietary supplements}, journal = {Drug Testing and Analysis}, volume = {14}, number = {11-12}, pages = {1864-1870}, abstract = {Abstract The detection of a putative 18-methyl-19-nortestosterone metabolite in a forensic bodybuilder's urine sample collected as part of a criminal proceeding has triggered a follow-up investigation. Four different dietary supplements in the possession of the suspect were examined with regard to possible precursor steroids. This led to the detection of the declared ingredient methoxydienone, which was confirmed by both, GC–MSMS and LC-HRMSMS. As neither 18-methyl-testosterone, nor 18-methyl-19-nortestosterone were detectable in the supplements, the possibility that the metabolite originates from methoxydienone was investigated. For this purpose, the metabolic fate of methoxydienone was studied in vitro using human HepG2 cells and in vivo by a single oral administration. While the 18-methyl-19-nortestosterone metabolite was not generated by HepG2 cells incubated with methoxydienone, it was observed in the urine samples collected at 2, 6, 10 and 24 h after methoxydienone administration. Moreover, the potential binding of methoxydienone as ligand to the human androgen receptor was modelled in silico in comparison with 18-methylnandrolone, for which androgen receptor activation had been shown in an in vitro approach before. In conclusion, we could ascribe the presence of the 18-methyl-19-nortestosterone metabolite in a forensic urine sample to originate from methoxydienone present in dietary supplements. Methoxydienone was observed to slowly degrade by demethylation of the methoxy substituent in liquid solutions. While no compound-specific intermediates were identified that allowed differentiation from other 18-methyl steroids, the 18-methyl-19-nortestosterone metabolite proved to be a suitable marker for reliable detection in doping analysis.}, ISSN = {1942-7603}, DOI = {10.1002/dta.3389}, url = {https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/abs/10.1002/dta.3389}, year = {2022}, type = {Journal Article} }  x  Detection of 18-methyl steroids: Case report on a forensic urine sample and corresponding dietary supplements

Abstract The detection of a putative 18-methyl-19-nortestosterone metabolite in a forensic bodybuilder's urine sample collected as part of a criminal proceeding has triggered a follow-up investigation. Four different dietary supplements in the possession of the suspect were examined with regard to possible precursor steroids. This led to the detection of the declared ingredient methoxydienone, which was confirmed by both, GC–MSMS and LC-HRMSMS. As neither 18-methyl-testosterone, nor 18-methyl-19-nortestosterone were detectable in the supplements, the possibility that the metabolite originates from methoxydienone was investigated. For this purpose, the metabolic fate of methoxydienone was studied in vitro using human HepG2 cells and in vivo by a single oral administration. While the 18-methyl-19-nortestosterone metabolite was not generated by HepG2 cells incubated with methoxydienone, it was observed in the urine samples collected at 2, 6, 10 and 24 h after methoxydienone administration. Moreover, the potential binding of methoxydienone as ligand to the human androgen receptor was modelled in silico in comparison with 18-methylnandrolone, for which androgen receptor activation had been shown in an in vitro approach before. In conclusion, we could ascribe the presence of the 18-methyl-19-nortestosterone metabolite in a forensic urine sample to originate from methoxydienone present in dietary supplements. Methoxydienone was observed to slowly degrade by demethylation of the methoxy substituent in liquid solutions. While no compound-specific intermediates were identified that allowed differentiation from other 18-methyl steroids, the 18-methyl-19-nortestosterone metabolite proved to be a suitable marker for reliable detection in doping analysis.

[179]

F. Yang, S. Liu, G. Wolber, M. Bureik, and M. K. Parr. Complete reaction phenotyping of Propranolol and 4-Hydroxypropranolol with the 19 enzymes of the human UGT1 and UGT2 families, Int J Mol Sci, 23(13):7476, 2022.
Links: [doi:10.3390/ijms23137476] [show BibTeX] [show abstract]  x  @article{RN321, author = {Yang, Fan and Liu, Sijie and Wolber, Gerhard and Bureik, Matthias and Parr, Maria Kristina}, title = {Complete reaction phenotyping of Propranolol and 4-Hydroxypropranolol with the 19 enzymes of the human UGT1 and UGT2 families}, journal = {International Journal of Molecular Sciences}, volume = {23}, number = {13}, pages = {7476}, abstract = {Propranolol is a competitive non-selective beta-receptor antagonist that is available on the market as a racemic mixture. In the present study, glucuronidation of propranolol and its equipotent phase I metabolite 4-hydroxypropranolol by all 19 members of the human UGT1 and UGT2 families was monitored. UGT1A7, UGT1A9, UGT1A10 and UGT2A1 were found to glucuronidate propranolol, with UGT1A7, UGT1A9 and UGT2A1 mainly acting on (S)-propranolol, while UGT1A10 displays the opposite stereoselectivity. UGT1A7, UGT1A9 and UGT2A1 were also found to glucuronidate 4-hydroxypropranolol. In contrast to propranolol, 4-hydroxypropranolol was found to be glucuronidated by UGT1A8 but not by UGT1A10. Additional biotransformations with 4-methoxypropanolol demonstrated different regioselectivities of these UGTs with respect to the aliphatic and aromatic hydroxy groups of the substrate. Modeling and molecular docking studies were performed to explain the stereoselective glucuronidation of the substrates under study.}, ISSN = {1422-0067}, DOI = {10.3390/ijms23137476}, url = {https://www.mdpi.com/1422-0067/23/13/7476}, year = {2022}, type = {Journal Article} }  x  Complete reaction phenotyping of Propranolol and 4-Hydroxypropranolol with the 19 enzymes of the human UGT1 and UGT2 families

Propranolol is a competitive non-selective beta-receptor antagonist that is available on the market as a racemic mixture. In the present study, glucuronidation of propranolol and its equipotent phase I metabolite 4-hydroxypropranolol by all 19 members of the human UGT1 and UGT2 families was monitored. UGT1A7, UGT1A9, UGT1A10 and UGT2A1 were found to glucuronidate propranolol, with UGT1A7, UGT1A9 and UGT2A1 mainly acting on (S)-propranolol, while UGT1A10 displays the opposite stereoselectivity. UGT1A7, UGT1A9 and UGT2A1 were also found to glucuronidate 4-hydroxypropranolol. In contrast to propranolol, 4-hydroxypropranolol was found to be glucuronidated by UGT1A8 but not by UGT1A10. Additional biotransformations with 4-methoxypropanolol demonstrated different regioselectivities of these UGTs with respect to the aliphatic and aromatic hydroxy groups of the substrate. Modeling and molecular docking studies were performed to explain the stereoselective glucuronidation of the substrates under study.

[178]

J. Zhao, S. Liu, C. A. Wolf, G. Wolber, M. K. Parr, and M. Bureik. Changes in Alprazolam metabolism by CYP3A43 mutants, Biomedicines, 10(12):3022, 2022.
Links: [doi:10.3390/biomedicines10123022] [show BibTeX]  x  @article{RN329, author = {Zhao, Jie and Liu, Sijie and Wolf, Clemens Alexander and Wolber, Gerhard and Parr, Maria Kristina and Bureik, Matthias}, title = {Changes in Alprazolam metabolism by CYP3A43 mutants}, journal = {Biomedicines}, volume = {10}, number = {12}, pages = {3022}, ISSN = {2227-9059}, DOI = {10.3390/biomedicines10123022}, url = {https://www.mdpi.com/2227-9059/10/12/3022}, year = {2022}, type = {Journal Article} }

[177]

J. Zhao, D. Machalz, S. Liu, C. A. Wolf, G. Wolber, M. K. Parr, and M. Bureik. Metabolism of the antipsychotic drug olanzapine by CYP3A43, Xenobiotica, :1-29, 2022.
Links: [doi:10.1080/00498254.2022.2078751] [show BibTeX] [show abstract]  x  @article{RN319, author = {Zhao, Jie and Machalz, David and Liu, Sijie and Wolf, Clemens Alexander and Wolber, Gerhard and Parr, Maria Kristina and Bureik, Matthias}, title = {Metabolism of the antipsychotic drug olanzapine by CYP3A43}, journal = {Xenobiotica}, pages = {1-29}, note = {doi: 10.1080/00498254.2022.2078751}, abstract = {Abstract1. Olanzapine is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. An intronic single nucleotide polymorphism (SNP) that highly significantly predicts increased olanzapine clearance (rs472660) was previously identified in the CYP3A43 gene, which encodes a cytochrome P450 enzyme. But until now there was no experimental evidence for the metabolism of olanzapine by the CYP3A43 enzyme.2. In the present study we provide this evidence, together with a thorough analysis of olanzapine metabolism by all human CYP3A enzymes. We also rationalize our findings by molecular docking experiments. Moreover, we describe the activities of several CYP3A43 mutants and present the first enzymatic activity data for the CYP3A43.3 variant; with respect to prostate cancer, this polymorphic variant is associated with both increased risk and increased mortality. The catalytic properties of the wild type enzyme and the tumor mutant were analyzed by molecular dynamics simulations, which fit very well with the observed experimental results.3. Our finding suggests that the SNP rs472660 likely causes an increased CYP3A43 expression level and demonstrate that, depending on the substrate under study, the tumor mutant CYP3A43.3 can have increased activity in comparison to the wild type enzyme CYP3A43.1.}, ISSN = {0049-8254}, DOI = {10.1080/00498254.2022.2078751}, url = {https://doi.org/10.1080/00498254.2022.2078751 https://www.tandfonline.com/doi/full/10.1080/00498254.2022.2078751}, year = {2022}, type = {Journal Article} }  x  Metabolism of the antipsychotic drug olanzapine by CYP3A43

Abstract1. Olanzapine is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. An intronic single nucleotide polymorphism (SNP) that highly significantly predicts increased olanzapine clearance (rs472660) was previously identified in the CYP3A43 gene, which encodes a cytochrome P450 enzyme. But until now there was no experimental evidence for the metabolism of olanzapine by the CYP3A43 enzyme.2. In the present study we provide this evidence, together with a thorough analysis of olanzapine metabolism by all human CYP3A enzymes. We also rationalize our findings by molecular docking experiments. Moreover, we describe the activities of several CYP3A43 mutants and present the first enzymatic activity data for the CYP3A43.3 variant; with respect to prostate cancer, this polymorphic variant is associated with both increased risk and increased mortality. The catalytic properties of the wild type enzyme and the tumor mutant were analyzed by molecular dynamics simulations, which fit very well with the observed experimental results.3. Our finding suggests that the SNP rs472660 likely causes an increased CYP3A43 expression level and demonstrate that, depending on the substrate under study, the tumor mutant CYP3A43.3 can have increased activity in comparison to the wild type enzyme CYP3A43.1.

[176]

J. Zhao, X. Zhang, Y. Wang, H. Huang, S. Sharma, S. S. Sharma, C. A. Wolf, S. Liu, G. Wolber, E. J. Sorensen, and M. Bureik. Exploring the chemical space of Proluciferins as probe substrates for human Cytochrome P450 enzymes, Appl Biochem Biotech, :, 2022.
Links: [doi:10.1007/s12010-022-04184-0] [show BibTeX] [show abstract]  x  @article{RN328, author = {Zhao, Jie and Zhang, Xue and Wang, Yueyin and Huang, Huimin and Sharma, Shishir and Sharma, Sangeeta Shrestha and Wolf, Clemens Alexander and Liu, Sijie and Wolber, Gerhard and Sorensen, Erik J. and Bureik, Matthias}, title = {Exploring the chemical space of Proluciferins as probe substrates for human Cytochrome P450 enzymes}, journal = {Applied Biochemistry and Biotechnology}, abstract = {We report the synthesis of 21 new proluciferin compounds that bear a small aliphatic ether group connected to the 6’ hydroxy function of firefly luciferin and either contain an acid or methyl ester function at the dihydrothiazole ring. Each of these compounds was found to be a substrate for some members of the human CYP1 and CYP3 families; a total of 92 new enzyme–substrate pairs were identified. In a screen of the whole human P450 complement (CYPome) with three selected proluciferin acid substrates, another 13 enzyme–substrate pairs were detected, which involve enzymes belonging to the CYP2, CYP4, CYP7, CYP21, and CYP27 families. All in all, we identified new probe substrates for members of seven out of 18 human CYP families.}, ISSN = {1559-0291}, DOI = {10.1007/s12010-022-04184-0}, url = {https://doi.org/10.1007/s12010-022-04184-0 https://link.springer.com/content/pdf/10.1007/s12010-022-04184-0.pdf}, year = {2022}, type = {Journal Article} }  x  Exploring the chemical space of Proluciferins as probe substrates for human Cytochrome P450 enzymes

We report the synthesis of 21 new proluciferin compounds that bear a small aliphatic ether group connected to the 6’ hydroxy function of firefly luciferin and either contain an acid or methyl ester function at the dihydrothiazole ring. Each of these compounds was found to be a substrate for some members of the human CYP1 and CYP3 families; a total of 92 new enzyme–substrate pairs were identified. In a screen of the whole human P450 complement (CYPome) with three selected proluciferin acid substrates, another 13 enzyme–substrate pairs were detected, which involve enzymes belonging to the CYP2, CYP4, CYP7, CYP21, and CYP27 families. All in all, we identified new probe substrates for members of seven out of 18 human CYP families.

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2021

[175]

A. Dolšak, D. Šribar, A. Scheffler, M. Grabowski, U. Švajger, S. Gobec, J. Holze, G. Weindl, G. Wolber, and M. Sova. Further hit optimization of 6-(trifluoromethyl)pyrimidin-2-amine based TLR8 modulators: Synthesis, biological evaluation and structure–activity relationships, Eur J Med Chem, 225:113809, 2021.
Links: [doi:10.1016/j.ejmech.2021.113809] [show BibTeX] [show abstract]  x  @article{RN311, author = {Dolšak, Ana and Šribar, Dora and Scheffler, Alexander and Grabowski, Maria and Švajger, Urban and Gobec, Stanislav and Holze, Janine and Weindl, Günther and Wolber, Gerhard and Sova, Matej}, title = {Further hit optimization of 6-(trifluoromethyl)pyrimidin-2-amine based TLR8 modulators: Synthesis, biological evaluation and structure–activity relationships}, journal = {European Journal of Medicinal Chemistry}, volume = {225}, pages = {113809}, abstract = {Toll-like receptor 8 (TLR8) is an endosomal TLR that has an important role in the innate human immune system, which is involved in numerous pathological conditions. Excessive activation of TLR8 can lead to inflammatory and autoimmune diseases, which highlights the need for development of TLR8 modulators. However, only a few small-molecule modulators that selectively target TLR8 have been developed. Here, we report the synthesis and systematic investigation of the structure–activity relationships of a series of novel TLR8 negative modulators based on previously reported 6-(trifluoromethyl)pyrimidin-2-amine derivatives. Four compounds showed low-micromolar concentration-dependent inhibition of TLR8-mediated signaling in HEK293 cells. These data confirm that the 6-trifluoromethyl group and two other substituents on positions 2 and 4 are important structural elements of pyrimidine-based TLR8 modulators. Substitution of the main scaffold at position 2 with a methylsulfonyl group or para hydroxy/hydroxymethyl substituted benzylamine is essential for potent negative modulation of TLR8. Our best-in-class TLR8-selective modulator 53 with IC50 value of 6.2 μM represents a promising small-molecule chemical probe for further optimization to a lead compound with potent immunomodulatory properties.}, keywords = {Toll-like receptors TLR8 Modulators Pyrimidines Immunomodulation Autoimmune disorders}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2021.113809}, url = {https://www.sciencedirect.com/science/article/pii/S0223523421006589}, year = {2021}, type = {Journal Article} }  x  Further hit optimization of 6-(trifluoromethyl)pyrimidin-2-amine based TLR8 modulators: Synthesis, biological evaluation and structure–activity relationships

Toll-like receptor 8 (TLR8) is an endosomal TLR that has an important role in the innate human immune system, which is involved in numerous pathological conditions. Excessive activation of TLR8 can lead to inflammatory and autoimmune diseases, which highlights the need for development of TLR8 modulators. However, only a few small-molecule modulators that selectively target TLR8 have been developed. Here, we report the synthesis and systematic investigation of the structure–activity relationships of a series of novel TLR8 negative modulators based on previously reported 6-(trifluoromethyl)pyrimidin-2-amine derivatives. Four compounds showed low-micromolar concentration-dependent inhibition of TLR8-mediated signaling in HEK293 cells. These data confirm that the 6-trifluoromethyl group and two other substituents on positions 2 and 4 are important structural elements of pyrimidine-based TLR8 modulators. Substitution of the main scaffold at position 2 with a methylsulfonyl group or para hydroxy/hydroxymethyl substituted benzylamine is essential for potent negative modulation of TLR8. Our best-in-class TLR8-selective modulator 53 with IC50 value of 6.2 μM represents a promising small-molecule chemical probe for further optimization to a lead compound with potent immunomodulatory properties.

[174]

M. Dumitrascuta, M. Bermudez, O. Trovato, J. De Neve, S. Ballet, G. Wolber, and M. Spetea. Antinociceptive efficacy of the μ-opioid/nociceptin peptide-based hybrid KGNOP1 in inflammatory pain without rewarding effects in mice: an experimental assessment and molecular docking, Molecules, 26(11):3267, 2021.
Links: [doi:10.3390/molecules26113267] [show BibTeX] [show abstract]  x  @article{RN308, author = {Dumitrascuta, Maria and Bermudez, Marcel and Trovato, Olga and De Neve, Jolien and Ballet, Steven and Wolber, Gerhard and Spetea, Mariana}, title = {Antinociceptive efficacy of the μ-opioid/nociceptin peptide-based hybrid KGNOP1 in inflammatory pain without rewarding effects in mice: an experimental assessment and molecular docking}, journal = {Molecules}, volume = {26}, number = {11}, pages = {3267}, abstract = {Opioids are the most effective analgesics, with most clinically available opioids being agonists to the µ-opioid receptor (MOR). The MOR is also responsible for their unwanted effects, including reward and opioid misuse leading to the current public health crisis. The imperative need for safer, non-addictive pain therapies drives the search for novel leads and new treatment strategies. In this study, the recently discovered MOR/nociceptin (NOP) receptor peptide hybrid KGNOP1 (H-Dmt-D-Arg-Aba-β-Ala-Arg-Tyr-Tyr-Arg-Ile-Lys-NH2) was evaluated following subcutaneous administration in mouse models of acute (formalin test) and chronic inflammatory pain (Complete Freund’s adjuvant-induced paw hyperalgesia), liabilities of spontaneous locomotion, conditioned place preference, and the withdrawal syndrome. KGNOP1 demonstrated dose-dependent antinociceptive effects in the formalin test, and efficacy in attenuating thermal hyperalgesia with prolonged duration of action. Antinociceptive effects of KGNOP1 were reversed by naltrexone and SB-612111, indicating the involvement of both MOR and NOP receptor agonism. In comparison with morphine, KGNOP1 was more potent and effective in mouse models of inflammatory pain. Unlike morphine, KGNOP1 displayed reduced detrimental liabilities, as no locomotor impairment nor rewarding and withdrawal effects were observed. Docking of KGNOP1 to the MOR and NOP receptors and subsequent 3D interaction pattern analyses provided valuable insights into its binding mode. The mixed MOR/NOP receptor peptide KGNOP1 holds promise in the effort to develop new analgesics for the treatment of various pain states with fewer MOR-mediated side effects, particularly abuse and dependence liabilities.}, ISSN = {1420-3049}, DOI = {10.3390/molecules26113267}, url = {https://www.mdpi.com/1420-3049/26/11/3267 https://res.mdpi.com/d_attachment/molecules/molecules-26-03267/article_deploy/molecules-26-03267-v3.pdf}, year = {2021}, type = {Journal Article} }  x  Antinociceptive efficacy of the μ-opioid/nociceptin peptide-based hybrid KGNOP1 in inflammatory pain without rewarding effects in mice: an experimental assessment and molecular docking

Opioids are the most effective analgesics, with most clinically available opioids being agonists to the µ-opioid receptor (MOR). The MOR is also responsible for their unwanted effects, including reward and opioid misuse leading to the current public health crisis. The imperative need for safer, non-addictive pain therapies drives the search for novel leads and new treatment strategies. In this study, the recently discovered MOR/nociceptin (NOP) receptor peptide hybrid KGNOP1 (H-Dmt-D-Arg-Aba-β-Ala-Arg-Tyr-Tyr-Arg-Ile-Lys-NH2) was evaluated following subcutaneous administration in mouse models of acute (formalin test) and chronic inflammatory pain (Complete Freund’s adjuvant-induced paw hyperalgesia), liabilities of spontaneous locomotion, conditioned place preference, and the withdrawal syndrome. KGNOP1 demonstrated dose-dependent antinociceptive effects in the formalin test, and efficacy in attenuating thermal hyperalgesia with prolonged duration of action. Antinociceptive effects of KGNOP1 were reversed by naltrexone and SB-612111, indicating the involvement of both MOR and NOP receptor agonism. In comparison with morphine, KGNOP1 was more potent and effective in mouse models of inflammatory pain. Unlike morphine, KGNOP1 displayed reduced detrimental liabilities, as no locomotor impairment nor rewarding and withdrawal effects were observed. Docking of KGNOP1 to the MOR and NOP receptors and subsequent 3D interaction pattern analyses provided valuable insights into its binding mode. The mixed MOR/NOP receptor peptide KGNOP1 holds promise in the effort to develop new analgesics for the treatment of various pain states with fewer MOR-mediated side effects, particularly abuse and dependence liabilities.

[173]

M. Janežič, K. Valjavec, K. B. Loboda, B. Herlah, I. Ogris, M. Kozorog, M. Podobnik, S. G. Grdadolnik, G. Wolber, and A. Perdih. Dynophore-based approach in virtual screening: a case of human DNA Topoisomerase IIα, Int J Mol Sci, 22(24):13474, 2021.
Links: [doi:10.3390/ijms222413474] [show BibTeX] [show abstract]  x  @article{RN314, author = {Janežič, Matej and Valjavec, Katja and Loboda, Kaja Bergant and Herlah, Barbara and Ogris, Iza and Kozorog, Mirijam and Podobnik, Marjetka and Grdadolnik, Simona Golič and Wolber, Gerhard and Perdih, Andrej}, title = {Dynophore-based approach in virtual screening: a case of human DNA Topoisomerase IIα}, journal = {International Journal of Molecular Sciences}, volume = {22}, number = {24}, pages = {13474}, abstract = {In this study, we utilized human DNA topoisomerase IIα as a model target to outline a dynophore-based approach to catalytic inhibitor design. Based on MD simulations of a known catalytic inhibitor and the native ATP ligand analog, AMP-PNP, we derived a joint dynophore model that supplements the static structure-based-pharmacophore information with a dynamic component. Subsequently, derived pharmacophore models were employed in a virtual screening campaign of a library of natural compounds. Experimental evaluation identified flavonoid compounds with promising topoisomerase IIα catalytic inhibition and binding studies confirmed interaction with the ATPase domain. We constructed a binding model through docking and extensively investigated it with molecular dynamics MD simulations, essential dynamics, and MM-GBSA free energy calculations, thus reconnecting the new results to the initial dynophore-based screening model. We not only demonstrate a new design strategy that incorporates a dynamic component of molecular recognition, but also highlight new derivates in the established flavonoid class of topoisomerase II inhibitors.}, ISSN = {1422-0067}, DOI = {10.3390/ijms222413474}, url = {https://www.mdpi.com/1422-0067/22/24/13474}, year = {2021}, type = {Journal Article} }  x  Dynophore-based approach in virtual screening: a case of human DNA Topoisomerase IIα

In this study, we utilized human DNA topoisomerase IIα as a model target to outline a dynophore-based approach to catalytic inhibitor design. Based on MD simulations of a known catalytic inhibitor and the native ATP ligand analog, AMP-PNP, we derived a joint dynophore model that supplements the static structure-based-pharmacophore information with a dynamic component. Subsequently, derived pharmacophore models were employed in a virtual screening campaign of a library of natural compounds. Experimental evaluation identified flavonoid compounds with promising topoisomerase IIα catalytic inhibition and binding studies confirmed interaction with the ATPase domain. We constructed a binding model through docking and extensively investigated it with molecular dynamics MD simulations, essential dynamics, and MM-GBSA free energy calculations, thus reconnecting the new results to the initial dynophore-based screening model. We not only demonstrate a new design strategy that incorporates a dynamic component of molecular recognition, but also highlight new derivates in the established flavonoid class of topoisomerase II inhibitors.

[172]

J. Y. Liu, D. Machalz, G. Wolber, E. J. Sorensen, and M. Bureik. New proluciferin substrates for human CYP4 family enzymes, Appl Biochem Biotech, 193(1):218-237, 2021.
Links: [doi:10.1007/s12010-020-03388-6] [show BibTeX] [show abstract]  x  @article{RN282, author = {Liu, J. Y. and Machalz, D. and Wolber, G. and Sorensen, E. J. and Bureik, M.}, title = {New proluciferin substrates for human CYP4 family enzymes}, journal = {Applied Biochemistry and Biotechnology}, volume = {193}, number = {1}, pages = {218-237}, note = {Nh3ox Times Cited:0 Cited References Count:48}, abstract = {We report the synthesis of seven new proluciferins for convenient activity determination of enzymes belonging to the cytochrome P450 (CYP) 4 family. Biotransformation of these probe substrates was monitored using each of the twelve human CYP4 family members, and eight were found to act at least on one of them. For all substrates, activity of CYP4Z1 was always highest, while that of CYP4F8 was always second highest. Site of metabolism (SOM) predictions involving SMARTCyp and docking experiments helped to rationalize the observed activity trends linked to substrate accessibility and reactivity. We further report the first homology model of CYP4F8 including suggested substrate recognition residues in a catalytically competent conformation accessed by replica exchange solute tempering (REST) simulations.}, keywords = {cytochrome p450 docking fission yeast homo sapiens pharmacology proluciferin site of metabolism prediction human cytochrome-p450 enzyme functional-characterization activation-energies prediction cancer autoantibodies identification selectivity expression smartcyp}, ISSN = {0273-2289}, DOI = {10.1007/s12010-020-03388-6}, url = {Go to ISI://WOS:000564584100001 https://link.springer.com/content/pdf/10.1007/s12010-020-03388-6.pdf}, year = {2021}, type = {Journal Article} }  x  New proluciferin substrates for human CYP4 family enzymes

We report the synthesis of seven new proluciferins for convenient activity determination of enzymes belonging to the cytochrome P450 (CYP) 4 family. Biotransformation of these probe substrates was monitored using each of the twelve human CYP4 family members, and eight were found to act at least on one of them. For all substrates, activity of CYP4Z1 was always highest, while that of CYP4F8 was always second highest. Site of metabolism (SOM) predictions involving SMARTCyp and docking experiments helped to rationalize the observed activity trends linked to substrate accessibility and reactivity. We further report the first homology model of CYP4F8 including suggested substrate recognition residues in a catalytically competent conformation accessed by replica exchange solute tempering (REST) simulations.

[171]

S. Loke, A. Stoll, D. Machalz, F. Botrè, G. Wolber, M. Bureik, and M. K. Parr. Corticosteroid biosynthesis revisited: No direct hydroxylation of Pregnenolone by Steroid 21-Hydroxylase, Front Endocrinol, 12(629):, 2021.
Links: [doi:10.3389/fendo.2021.633785] [show BibTeX] [show abstract]  x  @article{RN307, author = {Loke, Steffen and Stoll, Anna and Machalz, David and Botrè, Francesco and Wolber, Gerhard and Bureik, Matthias and Parr, Maria Kristina}, title = {Corticosteroid biosynthesis revisited: No direct hydroxylation of Pregnenolone by Steroid 21-Hydroxylase}, journal = {Frontiers in Endocrinology}, volume = {12}, number = {629}, abstract = {Cytochrome P450s (CYPs) are an essential family of enzymes in the human body. They play a crucial role in metabolism, especially in human steroid biosynthesis. Reactions catalyzed by these enzymes are highly stereo- and regio-specific. Lack or severe malfunctions of CYPs can cause severe diseases and even shorten life. Hence, investigations on metabolic reactions and structural requirements of substrates are crucial to gain further knowledge on the relevance of different enzymes in the human body functions and the origin of diseases. One key enzyme in the biosynthesis of gluco- and mineralocorticoids is CYP21A2, also known as steroid 21-hydroxylase. To investigate the steric and regional requirements of substrates for this enzyme, we performed whole-cell biotransformation assays using a strain of fission yeast Schizosaccharomyces pombe recombinantly expressing CYP21A2. The progestogens progesterone, pregnenolone, and their 17α-hydroxy-derivatives were used as substrates. After incubation, samples were analyzed using gas chromatography coupled to mass spectrometry. For progesterone and 17α-hydroxyprogesterone, their corresponding 21-hydroxylated metabolites 11-deoxycorticosterone and 11-deoxycortisol were detected, while after incubation of pregnenolone and 17α-hydroxypregnenolone, no hydroxylated product was observed. Findings were confirmed with authentic reference material. Molecular docking experiments agree with these results and suggest that interaction between the 3-oxo group and arginine-234 of the enzyme is a strict requirement. The presented results demonstrate once more that the presence of an oxo-group in position 3 of the steroid is indispensable, while a 3-hydroxy group prevents hydroxylation in position C-21 by CYP21A2. This knowledge may be transferred to other CYP21A2 substrates and hence help to gain essential insights into steroid metabolism.}, keywords = {corticosteroid,cytochrome P450,CYP21,GC-MS,Fission yeast (Schizosaccharomyces pombe),molecular docking,steroid biosynthesis}, ISSN = {1664-2392}, DOI = {10.3389/fendo.2021.633785}, url = {https://www.frontiersin.org/article/10.3389/fendo.2021.633785}, year = {2021}, type = {Journal Article} }  x  Corticosteroid biosynthesis revisited: No direct hydroxylation of Pregnenolone by Steroid 21-Hydroxylase

Cytochrome P450s (CYPs) are an essential family of enzymes in the human body. They play a crucial role in metabolism, especially in human steroid biosynthesis. Reactions catalyzed by these enzymes are highly stereo- and regio-specific. Lack or severe malfunctions of CYPs can cause severe diseases and even shorten life. Hence, investigations on metabolic reactions and structural requirements of substrates are crucial to gain further knowledge on the relevance of different enzymes in the human body functions and the origin of diseases. One key enzyme in the biosynthesis of gluco- and mineralocorticoids is CYP21A2, also known as steroid 21-hydroxylase. To investigate the steric and regional requirements of substrates for this enzyme, we performed whole-cell biotransformation assays using a strain of fission yeast Schizosaccharomyces pombe recombinantly expressing CYP21A2. The progestogens progesterone, pregnenolone, and their 17α-hydroxy-derivatives were used as substrates. After incubation, samples were analyzed using gas chromatography coupled to mass spectrometry. For progesterone and 17α-hydroxyprogesterone, their corresponding 21-hydroxylated metabolites 11-deoxycorticosterone and 11-deoxycortisol were detected, while after incubation of pregnenolone and 17α-hydroxypregnenolone, no hydroxylated product was observed. Findings were confirmed with authentic reference material. Molecular docking experiments agree with these results and suggest that interaction between the 3-oxo group and arginine-234 of the enzyme is a strict requirement. The presented results demonstrate once more that the presence of an oxo-group in position 3 of the steroid is indispensable, while a 3-hydroxy group prevents hydroxylation in position C-21 by CYP21A2. This knowledge may be transferred to other CYP21A2 substrates and hence help to gain essential insights into steroid metabolism.

[170]

D. Machalz, H. Li, W. Du, S. Sharma, S. Liu, M. Bureik, and G. Wolber. Discovery of a novel potent cytochrome P450 CYP4Z1 inhibitor, Eur J Med Chem, 215:113255, 2021.
Links: [doi:10.1016/j.ejmech.2021.113255] [show BibTeX] [show abstract]  x  @article{RN303, author = {Machalz, David and Li, Hongjie and Du, Wei and Sharma, Shishir and Liu, Sijie and Bureik, Matthias and Wolber, Gerhard}, title = {Discovery of a novel potent cytochrome P450 CYP4Z1 inhibitor}, journal = {European Journal of Medicinal Chemistry}, volume = {215}, pages = {113255}, abstract = {Human cytochrome P450 enzyme CYP4Z1 represents a promising target for the treatment of a multitude of malignancies including breast cancer. The most active known non-covalent inhibitor (1-benzylimidazole) only shows low micromolar affinity to CYP4Z1. We report a new, highly active inhibitor for CYP4Z1 showing confirmed binding in an enzymatic assay and an IC50 value of 63 ± 19 nM in stably transfected MCF-7 cells overexpressing CYP4Z1. The new inhibitor was identified by a systematically developed virtual screening protocol. Binding was rationalized using a carefully elaborated 3D pharmacophore hypothesis and thoroughly characterized using extensive molecular dynamics simulations and dynamic 3D pharmacophore (dynophore) analyses. This novel inhibitor represents a valuable pharmacological tool to accelerate characterization of the still understudied CYP4Z1 and might pave the way for a new treatment strategy in CYP4Z1-associated malignancies. The presented in silico model for predicting CYP4Z1 interaction provides novel mechanistic insights and revealed that the drug ozagrel interacts with CYP4Z1.}, keywords = {Breast cancer CYP4Z1 Enzyme inhibition Molecular modeling Virtual screening 3D pharmacophores}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2021.113255}, url = {https://www.sciencedirect.com/science/article/pii/S0223523421001045}, year = {2021}, type = {Journal Article} }  x  Discovery of a novel potent cytochrome P450 CYP4Z1 inhibitor

Human cytochrome P450 enzyme CYP4Z1 represents a promising target for the treatment of a multitude of malignancies including breast cancer. The most active known non-covalent inhibitor (1-benzylimidazole) only shows low micromolar affinity to CYP4Z1. We report a new, highly active inhibitor for CYP4Z1 showing confirmed binding in an enzymatic assay and an IC50 value of 63 ± 19 nM in stably transfected MCF-7 cells overexpressing CYP4Z1. The new inhibitor was identified by a systematically developed virtual screening protocol. Binding was rationalized using a carefully elaborated 3D pharmacophore hypothesis and thoroughly characterized using extensive molecular dynamics simulations and dynamic 3D pharmacophore (dynophore) analyses. This novel inhibitor represents a valuable pharmacological tool to accelerate characterization of the still understudied CYP4Z1 and might pave the way for a new treatment strategy in CYP4Z1-associated malignancies. The presented in silico model for predicting CYP4Z1 interaction provides novel mechanistic insights and revealed that the drug ozagrel interacts with CYP4Z1.

[169]

D. Machalz, S. Pach, M. Bermudez, M. Bureik, and G. Wolber. Structural insights into understudied human cytochrome P450 enzymes, Drug Discov Today, 26(10):2456-2464, 2021.
Links: [doi:10.1016/j.drudis.2021.06.006] [show BibTeX] [show abstract]  x  @article{RN306, author = {Machalz, David and Pach, Szymon and Bermudez, Marcel and Bureik, Matthias and Wolber, Gerhard}, title = {Structural insights into understudied human cytochrome P450 enzymes}, journal = {Drug Discovery Today}, volume = {26}, number = {10}, pages = {2456-2464}, abstract = {Human cytochrome P450 (CYP) enzymes are widely known for their pivotal role in the metabolism of drugs and other xenobiotics as well as of endogenous chemicals. In addition, CYPs are involved in numerous pathophysiological pathways and, hence, are therapeutically relevant. Remarkably, a portion of promising CYP targets is still understudied and, as a consequence, untargeted, despite their huge therapeutic potential. An increasing number of X-ray and cryo-electron microscopy (EM) structures for CYPs have recently provided new insights into the structural basis of CYP function and potential ligand binding. This structural knowledge of CYP functionality is essential for both understanding metabolism and exploiting understudied CYPs as drug targets. In this review, we summarize and highlight structural knowledge about this enzyme class, with a focus on understudied CYPs and resulting opportunities for structure-based drug design. Teaser: This review summarizes recent structural insights into understudied cytochrome P450 enzymes. We highlight the impact of molecular modeling for mechanistically explaining pathophysiological effects establishing understudied CYPs as promising drug targets.}, keywords = {CYP Cytochrome P450 Protein structure Cancer Genetic disease Mutation Homology modeling Metabolism Molecular modeling}, ISSN = {1359-6446}, DOI = {10.1016/j.drudis.2021.06.006}, url = {https://www.sciencedirect.com/science/article/pii/S1359644621002786 https://www.sciencedirect.com/science/article/abs/pii/S1359644621002786?via%3Dihub}, year = {2021}, type = {Journal Article} }  x  Structural insights into understudied human cytochrome P450 enzymes

Human cytochrome P450 (CYP) enzymes are widely known for their pivotal role in the metabolism of drugs and other xenobiotics as well as of endogenous chemicals. In addition, CYPs are involved in numerous pathophysiological pathways and, hence, are therapeutically relevant. Remarkably, a portion of promising CYP targets is still understudied and, as a consequence, untargeted, despite their huge therapeutic potential. An increasing number of X-ray and cryo-electron microscopy (EM) structures for CYPs have recently provided new insights into the structural basis of CYP function and potential ligand binding. This structural knowledge of CYP functionality is essential for both understanding metabolism and exploiting understudied CYPs as drug targets. In this review, we summarize and highlight structural knowledge about this enzyme class, with a focus on understudied CYPs and resulting opportunities for structure-based drug design. Teaser: This review summarizes recent structural insights into understudied cytochrome P450 enzymes. We highlight the impact of molecular modeling for mechanistically explaining pathophysiological effects establishing understudied CYPs as promising drug targets.

[168]

T. Meşeli, S. D. Doğan, M. G. Gündüz, Z. Kökbudak, S. Skaro Bogojevic, T. Noonan, S. Vojnovic, G. Wolber, and J. Nikodinovic-Runic. Design, synthesis, antibacterial activity evaluation and molecular modeling studies of new sulfonamides containing a sulfathiazole moiety, New J Chem, 45(18):8166-8177, 2021.
Links: [doi:10.1039/D1NJ00150G] [show BibTeX] [show abstract]  x  @article{RN309, author = {Meşeli, Tuğba and Doğan, Sengül Dilem and Gündüz, Miyase Gözde and Kökbudak, Zülbiye and Skaro Bogojevic, Sanja and Noonan, Theresa and Vojnovic, Sandra and Wolber, Gerhard and Nikodinovic-Runic, Jasmina}, title = {Design, synthesis, antibacterial activity evaluation and molecular modeling studies of new sulfonamides containing a sulfathiazole moiety}, journal = {New Journal of Chemistry}, volume = {45}, number = {18}, pages = {8166-8177}, abstract = {Sulfonamides represent the oldest synthetic antibacterial agents; however, their central position in controlling bacterial diseases has been seriously damaged by the development of widespread resistance. Herein, we revisited sulfathiazole, a commercial member of antibacterial sulfa drugs, intending to overcome sulfonamide resistance and identify new drug candidates through molecular modifications. We synthesized twelve sulfonamides (SA1–SA12) by replacing the amino group on the phenyl ring with various substituents and introducing a thiophene ring on the core scaffold of sulfathiazole. The obtained compounds and additionally two commercial sulfonamides, sulfathiazole and sulfadiazine, were extensively screened for their antimicrobial activities. The results indicated that new sulfonamides, unlike traditional ones, were selectively effective against various Staphylococcus aureus strains. Introducing a bulky lipophilic substituent at the para position of the phenyl ring significantly increased the antibacterial activities of the compounds against Staphylococcus aureus. The compounds demonstrating favourable selectivity indices were further evaluated for their membrane potential perturbation and DNA interaction properties. The obtained data showed that these are not supporting mechanisms for the antibacterial activities of the modified sulfathiazole derivatives. In order to rationalize the activity of the three most active compounds, SA7, SA11 and SA12, against S. aureus ATCC 25923, their binding hypotheses within the catalytic site of Staphylococcus aureus dihydropteroate synthase, the validated target enzyme of sulfonamides, were generated via molecular docking and further dissected using molecular dynamics simulations and dynamic 3D pharmacophores (dynophores).}, ISSN = {1144-0546}, DOI = {10.1039/D1NJ00150G}, url = {http://dx.doi.org/10.1039/D1NJ00150G https://pubs.rsc.org/en/content/articlepdf/2021/nj/d1nj00150g}, year = {2021}, type = {Journal Article} }  x  Design, synthesis, antibacterial activity evaluation and molecular modeling studies of new sulfonamides containing a sulfathiazole moiety

Sulfonamides represent the oldest synthetic antibacterial agents; however, their central position in controlling bacterial diseases has been seriously damaged by the development of widespread resistance. Herein, we revisited sulfathiazole, a commercial member of antibacterial sulfa drugs, intending to overcome sulfonamide resistance and identify new drug candidates through molecular modifications. We synthesized twelve sulfonamides (SA1–SA12) by replacing the amino group on the phenyl ring with various substituents and introducing a thiophene ring on the core scaffold of sulfathiazole. The obtained compounds and additionally two commercial sulfonamides, sulfathiazole and sulfadiazine, were extensively screened for their antimicrobial activities. The results indicated that new sulfonamides, unlike traditional ones, were selectively effective against various Staphylococcus aureus strains. Introducing a bulky lipophilic substituent at the para position of the phenyl ring significantly increased the antibacterial activities of the compounds against Staphylococcus aureus. The compounds demonstrating favourable selectivity indices were further evaluated for their membrane potential perturbation and DNA interaction properties. The obtained data showed that these are not supporting mechanisms for the antibacterial activities of the modified sulfathiazole derivatives. In order to rationalize the activity of the three most active compounds, SA7, SA11 and SA12, against S. aureus ATCC 25923, their binding hypotheses within the catalytic site of Staphylococcus aureus dihydropteroate synthase, the validated target enzyme of sulfonamides, were generated via molecular docking and further dissected using molecular dynamics simulations and dynamic 3D pharmacophores (dynophores).

[167]

R. Ottanà, P. Paoli, M. Cappiello, T. N. Nguyen, I. Adornato, A. Del Corso, M. Genovese, I. Nesi, R. Moschini, A. Naß, G. Wolber, and R. Maccari. In search for multi-target ligands as potential agents for diabetes mellitus and its complications—a structure-activity relationship study on inhibitors of aldose reductase and Protein Tyrosine Phosphatase 1B, Molecules, 26(2):330, 2021.
Links: [doi:10.3390/molecules26020330] [show BibTeX] [show abstract]  x  @article{RN299, author = {Ottanà, Rosaria and Paoli, Paolo and Cappiello, Mario and Nguyen, Trung Ngoc and Adornato, Ilenia and Del Corso, Antonella and Genovese, Massimo and Nesi, Ilaria and Moschini, Roberta and Naß, Alexandra and Wolber, Gerhard and Maccari, Rosanna}, title = {In search for multi-target ligands as potential agents for diabetes mellitus and its complications—a structure-activity relationship study on inhibitors of aldose reductase and Protein Tyrosine Phosphatase 1B}, journal = {Molecules}, volume = {26}, number = {2}, pages = {330}, abstract = {Diabetes mellitus (DM) is a complex disease which currently affects more than 460 million people and is one of the leading cause of death worldwide. Its development implies numerous metabolic dysfunctions and the onset of hyperglycaemia-induced chronic complications. Multiple ligands can be rationally designed for the treatment of multifactorial diseases, such as DM, with the precise aim of simultaneously controlling multiple pathogenic mechanisms related to the disease and providing a more effective and safer therapeutic treatment compared to combinations of selective drugs. Starting from our previous findings that highlighted the possibility to target both aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two enzymes strictly implicated in the development of DM and its complications, we synthesised 3-(5-arylidene-4-oxothiazolidin-3-yl)propanoic acids and analogous 2-butenoic acid derivatives, with the aim of balancing the effectiveness of dual AR/PTP1B inhibitors which we had identified as designed multiple ligands (DMLs). Out of the tested compounds, 4f exhibited well-balanced AR/PTP1B inhibitory effects at low micromolar concentrations, along with interesting insulin-sensitizing activity in murine C2C12 cell cultures. The SARs here highlighted along with their rationalization by in silico docking experiments into both target enzymes provide further insights into this class of inhibitors for their development as potential DML antidiabetic candidates.}, ISSN = {1420-3049}, DOI = {10.3390/molecules26020330}, url = {https://www.mdpi.com/1420-3049/26/2/330 https://res.mdpi.com/d_attachment/molecules/molecules-26-00330/article_deploy/molecules-26-00330-v3.pdf}, year = {2021}, type = {Journal Article} }  x  In search for multi-target ligands as potential agents for diabetes mellitus and its complications—a structure-activity relationship study on inhibitors of aldose reductase and Protein Tyrosine Phosphatase 1B

Diabetes mellitus (DM) is a complex disease which currently affects more than 460 million people and is one of the leading cause of death worldwide. Its development implies numerous metabolic dysfunctions and the onset of hyperglycaemia-induced chronic complications. Multiple ligands can be rationally designed for the treatment of multifactorial diseases, such as DM, with the precise aim of simultaneously controlling multiple pathogenic mechanisms related to the disease and providing a more effective and safer therapeutic treatment compared to combinations of selective drugs. Starting from our previous findings that highlighted the possibility to target both aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two enzymes strictly implicated in the development of DM and its complications, we synthesised 3-(5-arylidene-4-oxothiazolidin-3-yl)propanoic acids and analogous 2-butenoic acid derivatives, with the aim of balancing the effectiveness of dual AR/PTP1B inhibitors which we had identified as designed multiple ligands (DMLs). Out of the tested compounds, 4f exhibited well-balanced AR/PTP1B inhibitory effects at low micromolar concentrations, along with interesting insulin-sensitizing activity in murine C2C12 cell cultures. The SARs here highlighted along with their rationalization by in silico docking experiments into both target enzymes provide further insights into this class of inhibitors for their development as potential DML antidiabetic candidates.

[166]

S. Pach, T. N. Nguyen, J. Trimpert, D. Kunec, N. Osterrieder, and G. Wolber. ACE2 variants indicate potential SARS-CoV-2-Susceptibility in animals: An extensive molecular dynamics study, Mol Inf, 40(9):2100031, 2021.
Links: [doi:10.1002/minf.202100031] [show BibTeX]  x  @article{RN310, author = {Pach, Szymon and Nguyen, Trung Ngoc and Trimpert, Jakob and Kunec, Dusan and Osterrieder, Nikolaus and Wolber, Gerhard}, title = {ACE2 variants indicate potential SARS-CoV-2-Susceptibility in animals: An extensive molecular dynamics study}, journal = {Molecular Informatics}, volume = {40}, number = {9}, pages = {2100031}, DOI = {10.1002/minf.202100031}, url = {https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/minf.202100031?download=true}, year = {2021}, type = {Journal Article} }

[165]

S. Sharma, S. Liu, P. Durairaj, D. Machalz, G. Wolber, and M. Bureik. A convenient test system for the identification of CYP4V2 inhibitors, Mol Vis, 27:601-607, 2021.
Links: [show BibTeX] [show abstract]  x  @article{RN312, author = {Sharma, Shishir and Liu, Sijie and Durairaj, Pradeepraj and Machalz, David and Wolber, Gerhard and Bureik, Matthias}, title = {A convenient test system for the identification of CYP4V2 inhibitors}, journal = {Molecular Vision}, volume = {27}, pages = {601-607}, note = {mv-v27-601.pdf}, abstract = {Purpose: Polymorphisms in the gene that codes for the human cytochrome P450 enzyme CYP4V2 are a cause of Bietti crystalline dystrophy (BCD). Therefore, inhibition of CYP4V2 activity may well be a cause of visual disability. However, monitoring the fatty acid hydroxylation reactions catalyzed by this enzyme is tedious and not well suited for inhibitor screening. Methods: We investigated the use of proluciferin compounds as probe substrates for efficient and convenient determination of CYP4V2 activity. Results: Ten proluciferins were tested for conversion by CYP4V2, and eight were found to be substrates of this enzyme. One point inhibitor assays were performed using luciferin 6' 3-furfuryl ether methyl ester (luciferin-3FEME) as the probe substrate and 12 test compounds. As expected, HET0016 had by far the strongest effect, while two other compounds (including osilodrostat) also displayed statistically significant inhibitory potency. The half maximal inhibitory concentration (IC50) for HET0016 was determined to be 179 nM. A recently identified potent inhibitor of human CYP4Z1 was found not to inhibit CYP4V2. To explore the selectivity of this compound between CYP4Z1 and CYP4V2, we developed a homology model of CYP4V2 and conducted docking experiments. Conclusions: We provide the first protocol for a robust and convenient CYP4V2 inhibitor assay that does not depend on fatty acid analysis but can be simply monitored with luminescence. Moreover, we demonstrate additional evidence for the concern that compounds with CYP-inhibitory properties may inhibit CYP4V2 activity and thus, possibly cause visual disability.}, url = {http://www.molvis.org/molvis/v27/601}, year = {2021}, type = {Journal Article} }  x  A convenient test system for the identification of CYP4V2 inhibitors

Purpose: Polymorphisms in the gene that codes for the human cytochrome P450 enzyme CYP4V2 are a cause of Bietti crystalline dystrophy (BCD). Therefore, inhibition of CYP4V2 activity may well be a cause of visual disability. However, monitoring the fatty acid hydroxylation reactions catalyzed by this enzyme is tedious and not well suited for inhibitor screening. Methods: We investigated the use of proluciferin compounds as probe substrates for efficient and convenient determination of CYP4V2 activity. Results: Ten proluciferins were tested for conversion by CYP4V2, and eight were found to be substrates of this enzyme. One point inhibitor assays were performed using luciferin 6' 3-furfuryl ether methyl ester (luciferin-3FEME) as the probe substrate and 12 test compounds. As expected, HET0016 had by far the strongest effect, while two other compounds (including osilodrostat) also displayed statistically significant inhibitory potency. The half maximal inhibitory concentration (IC50) for HET0016 was determined to be 179 nM. A recently identified potent inhibitor of human CYP4Z1 was found not to inhibit CYP4V2. To explore the selectivity of this compound between CYP4Z1 and CYP4V2, we developed a homology model of CYP4V2 and conducted docking experiments. Conclusions: We provide the first protocol for a robust and convenient CYP4V2 inhibitor assay that does not depend on fatty acid analysis but can be simply monitored with luminescence. Moreover, we demonstrate additional evidence for the concern that compounds with CYP-inhibitory properties may inhibit CYP4V2 activity and thus, possibly cause visual disability.

[164]

C. Tauber, R. Wamser, C. Arkona, M. Tuegend, U. B. Abdul Aziz, S. Pach, R. Schulz, D. Jochmans, G. Wolber, J. Neyts, and J. Rademann. Chemical evolution of antivirals against enterovirus D68 through protein-templated Knoevenagel reactions, Angewandte Chemie International Edition, 60(24):13294-13301, 2021.
Links: [doi:10.1002/anie.202102074] [show BibTeX] [show abstract]  x  @article{RN305, author = {Tauber, Carolin and Wamser, Rebekka and Arkona, Christoph and Tuegend, Marisa and Abdul Aziz, Umer Bin and Pach, Szymon and Schulz, Robert and Jochmans, Dirk and Wolber, Gerhard and Neyts, Johan and Rademann, Joerg}, title = {Chemical evolution of antivirals against enterovirus D68 through protein-templated Knoevenagel reactions}, journal = {Angewandte Chemie International Edition}, volume = {60}, number = {24}, pages = {13294-13301}, note = {https://doi.org/10.1002/anie.202102074}, abstract = {The generation of bioactive molecules from inactive precursors is a crucial step in the chemical evolution of life, however, mechanistic insights into this aspect of abiogenesis are scarce. Here, we investigate the protein-catalyzed formation of antivirals by the 3C-protease of enterovirus D68. The enzyme induces aldol condensations yielding inhibitors with antiviral activity in cells. Kinetic and thermodynamic analyses reveal that the bioactivity emerges from a dynamic reaction system including inhibitor formation, alkylation of the protein target by the inhibitors, and competitive addition of non-protein nucleophiles to the inhibitors. The most active antivirals are slowly reversible inhibitors with elongated target residence times. The study reveals first examples for the chemical evolution of bio-actives through protein-catalyzed, non-enzymatic CC-couplings. The discovered mechanism works under physiological conditions and might constitute a native process of drug development.}, keywords = {Chemical Evolution, Protein-templated reactions, Antivirals, Protease inhibitors, Fragment-based drug discovery}, ISSN = {1433-7851}, DOI = {10.1002/anie.202102074}, url = {https://doi.org/10.1002/anie.202102074 https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/anie.202102074?download= true}, year = {2021}, type = {Journal Article} }  x  Chemical evolution of antivirals against enterovirus D68 through protein-templated Knoevenagel reactions

The generation of bioactive molecules from inactive precursors is a crucial step in the chemical evolution of life, however, mechanistic insights into this aspect of abiogenesis are scarce. Here, we investigate the protein-catalyzed formation of antivirals by the 3C-protease of enterovirus D68. The enzyme induces aldol condensations yielding inhibitors with antiviral activity in cells. Kinetic and thermodynamic analyses reveal that the bioactivity emerges from a dynamic reaction system including inhibitor formation, alkylation of the protein target by the inhibitors, and competitive addition of non-protein nucleophiles to the inhibitors. The most active antivirals are slowly reversible inhibitors with elongated target residence times. The study reveals first examples for the chemical evolution of bio-actives through protein-catalyzed, non-enzymatic CC-couplings. The discovered mechanism works under physiological conditions and might constitute a native process of drug development.

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2020

[163]

M. Bermudez, M. Grabowski, M. S. Murgueitio, M. Tiemann, P. Varga, T. Rudolf, G. Wolber, G. Weindl, and J. Rademann. Biological characterization, mechanistic investigation and structure-activity relationships of chemically stable TLR2 antagonists, ChemMedChem, 15(14):1364-1371, 2020.
Links: [doi:10.1002/cmdc.202000060] [show BibTeX] [show abstract]  x  @article{RN284, author = {Bermudez, M. and Grabowski, M. and Murgueitio, M. S. and Tiemann, M. and Varga, P. and Rudolf, T. and Wolber, G. and Weindl, G. and Rademann, J.}, title = {Biological characterization, mechanistic investigation and structure-activity relationships of chemically stable TLR2 antagonists}, journal = {Chemmedchem}, volume = {15}, number = {14}, pages = {1364-1371}, note = {Mm1dj Times Cited:0 Cited References Count:34}, abstract = {Toll-like receptors (TLRs) build the first barrier in the innate immune response and therefore represent promising targets for the modulation of inflammatory processes. Recently, the pyrogallol-containing TLR2 antagonists CU-CPT22 and MMG-11 were reported; however, their 1,2,3-triphenol motif renders them highly susceptible to oxidation and excludes them from use in extended experiments under aerobic conditions. Therefore, we have developed a set of novel TLR2 antagonists (1-9) based on the systematic variation of substructures, linker elements, and the hydrogen-bonding pattern of the pyrogallol precursors by using chemically robust building blocks. The novel series of chemically stable and synthetically accessible TLR2 antagonists (1-9) was pharmacologically characterized, and the potential binding modes of the active compounds were evaluated structurally. Our results provide new insights into structure-activity relationships and allow rationalization of structural binding characteristics. Moreover, they support the hypothesis that this class of TLR ligands bind solely to TLR2 and do not directly interact with TLR1 or TLR6 of the functional heterodimer. The most active compound from this series (6), is chemically stable, nontoxic, TLR2-selective, and shows a similar activity with regard to the pyrogallol starting points, thus indicating the variability of the hydrogen bonding pattern.}, keywords = {chemical synthesis inflammation molecular modeling structure-based design tlr selectivity toll-like receptors pattern-recognition receptors discovery peptides agonists design}, ISSN = {1860-7179}, DOI = {10.1002/cmdc.202000060}, url = {Go to ISI://WOS:000537253200001 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7496872/pdf/CMDC-15-1364.pdf}, year = {2020}, type = {Journal Article} }  x  Biological characterization, mechanistic investigation and structure-activity relationships of chemically stable TLR2 antagonists

Toll-like receptors (TLRs) build the first barrier in the innate immune response and therefore represent promising targets for the modulation of inflammatory processes. Recently, the pyrogallol-containing TLR2 antagonists CU-CPT22 and MMG-11 were reported; however, their 1,2,3-triphenol motif renders them highly susceptible to oxidation and excludes them from use in extended experiments under aerobic conditions. Therefore, we have developed a set of novel TLR2 antagonists (1-9) based on the systematic variation of substructures, linker elements, and the hydrogen-bonding pattern of the pyrogallol precursors by using chemically robust building blocks. The novel series of chemically stable and synthetically accessible TLR2 antagonists (1-9) was pharmacologically characterized, and the potential binding modes of the active compounds were evaluated structurally. Our results provide new insights into structure-activity relationships and allow rationalization of structural binding characteristics. Moreover, they support the hypothesis that this class of TLR ligands bind solely to TLR2 and do not directly interact with TLR1 or TLR6 of the functional heterodimer. The most active compound from this series (6), is chemically stable, nontoxic, TLR2-selective, and shows a similar activity with regard to the pyrogallol starting points, thus indicating the variability of the hydrogen bonding pattern.

[162]

K. Denzinger, T. N. Nguyen, T. Noonan, G. Wolber, and M. Bermudez. Biased ligands differentially shape the conformation of the extracellular loop region in 5-HT2B receptors, Int J Mol Sci, 21(24):9728, 2020.
Links: [doi:10.3390/ijms21249728] [show BibTeX] [show abstract]  x  @article{RN301, author = {Denzinger, Katrin and Nguyen, Trung Ngoc and Noonan, Theresa and Wolber, Gerhard and Bermudez, Marcel}, title = {Biased ligands differentially shape the conformation of the extracellular loop region in 5-HT2B receptors}, journal = {International Journal of Molecular Sciences}, volume = {21}, number = {24}, pages = {9728}, note = {Denzinger, Katrin Nguyen, Trung Ngoc Noonan, Theresa Wolber, Gerhard Bermudez, Marcel eng 407626949/Deutsche Forschungsgemeinschaft Switzerland Int J Mol Sci. 2020 Dec 20;21(24). pii: ijms21249728. doi: 10.3390/ijms21249728.}, abstract = {G protein-coupled receptors are linked to various intracellular transducers, each pathway associated with different physiological effects. Biased ligands, capable of activating one pathway over another, are gaining attention for their therapeutic potential, as they could selectively activate beneficial pathways whilst avoiding those responsible for adverse effects. We performed molecular dynamics simulations with known beta-arrestin-biased ligands like lysergic acid diethylamide and ergotamine in complex with the 5-HT2B receptor and discovered that the extent of ligand bias is directly connected with the degree of closure of the extracellular loop region. Given a loose allosteric coupling of extracellular and intracellular receptor regions, we delineate a concept for biased signaling at serotonin receptors, by which conformational interference with binding pocket closure restricts the signaling repertoire of the receptor. Molecular docking studies of biased ligands gathered from the BiasDB demonstrate that larger ligands only show plausible docking poses in the ergotamine-bound structure, highlighting the conformational constraints associated with bias. This emphasizes the importance of selecting the appropriate receptor conformation on which to base virtual screening workflows in structure-based drug design of biased ligands. As this mechanism of ligand bias has also been observed for muscarinic receptors, our studies provide a general mechanism of signaling bias transferable between aminergic receptors.}, keywords = {Gpcr biased signaling conformational descriptor drug design molecular dynamics pharmacophore serotonin receptors virtual screening}, ISSN = {1422-0067}, DOI = {10.3390/ijms21249728}, url = {https://www.mdpi.com/1422-0067/21/24/9728 https://res.mdpi.com/d_attachment/ijms/ijms-21-09728/article_deploy/ijms-21-09728.pdf}, year = {2020}, type = {Journal Article} }  x  Biased ligands differentially shape the conformation of the extracellular loop region in 5-HT2B receptors

G protein-coupled receptors are linked to various intracellular transducers, each pathway associated with different physiological effects. Biased ligands, capable of activating one pathway over another, are gaining attention for their therapeutic potential, as they could selectively activate beneficial pathways whilst avoiding those responsible for adverse effects. We performed molecular dynamics simulations with known beta-arrestin-biased ligands like lysergic acid diethylamide and ergotamine in complex with the 5-HT2B receptor and discovered that the extent of ligand bias is directly connected with the degree of closure of the extracellular loop region. Given a loose allosteric coupling of extracellular and intracellular receptor regions, we delineate a concept for biased signaling at serotonin receptors, by which conformational interference with binding pocket closure restricts the signaling repertoire of the receptor. Molecular docking studies of biased ligands gathered from the BiasDB demonstrate that larger ligands only show plausible docking poses in the ergotamine-bound structure, highlighting the conformational constraints associated with bias. This emphasizes the importance of selecting the appropriate receptor conformation on which to base virtual screening workflows in structure-based drug design of biased ligands. As this mechanism of ligand bias has also been observed for muscarinic receptors, our studies provide a general mechanism of signaling bias transferable between aminergic receptors.

[161]

W. Du, D. Machalz, Q. Yan, E. J. Sorensen, G. Wolber, and M. Bureik. Importance of asparagine-381 and arginine-487 for substrate recognition in CYP4Z1, Biochem Pharmacol, 174:113850, 2020.
Links: [doi:10.1016/j.bcp.2020.113850] [show BibTeX] [show abstract]  x  @article{RN280, author = {Du, Wei and Machalz, David and Yan, Qi and Sorensen, Erik J. and Wolber, Gerhard and Bureik, Matthias}, title = {Importance of asparagine-381 and arginine-487 for substrate recognition in CYP4Z1}, journal = {Biochemical Pharmacology}, volume = {174}, pages = {113850}, abstract = {The human cytochrome P450 enzyme CYP4Z1 remains an understudied enzyme despite its association with poor prognosis and overexpression in breast cancer. Hence, CYP4Z1 has previously been suggested as an anti-breast cancer target. In the present study we employed extended mutation analysis to increase our understanding of the substrate binding mode of this enzyme. In a combined in vitro and in silico approach we show for the first time that residue Arg487 plays an important role in substrate recognition and binding of CYP4Z1. Using a large array of recombinant CYP4Z1 mutants we show that, apart from Asn381, all other postulated binding residues only play an auxiliary role in substrate recognition and binding. Different substrate interaction motifs were identified via dynamic pharmacophores (dynophores) and their impact on catalytically competent substrate binding was classified. These new insights on the substrate recognition and binding mode represent an important step towards the rational design of CYP4Z1 prodrugs and guide further investigations into the so far poorly understood physiological role of CYP4Z1.}, keywords = {Breast cancer CYP4Z1 Mutational studies Molecular modeling Substrate recognition}, ISSN = {0006-2952}, DOI = {10.1016/j.bcp.2020.113850}, url = {http://www.sciencedirect.com/science/article/pii/S000629522030071X}, year = {2020}, type = {Journal Article} }  x  Importance of asparagine-381 and arginine-487 for substrate recognition in CYP4Z1

The human cytochrome P450 enzyme CYP4Z1 remains an understudied enzyme despite its association with poor prognosis and overexpression in breast cancer. Hence, CYP4Z1 has previously been suggested as an anti-breast cancer target. In the present study we employed extended mutation analysis to increase our understanding of the substrate binding mode of this enzyme. In a combined in vitro and in silico approach we show for the first time that residue Arg487 plays an important role in substrate recognition and binding of CYP4Z1. Using a large array of recombinant CYP4Z1 mutants we show that, apart from Asn381, all other postulated binding residues only play an auxiliary role in substrate recognition and binding. Different substrate interaction motifs were identified via dynamic pharmacophores (dynophores) and their impact on catalytically competent substrate binding was classified. These new insights on the substrate recognition and binding mode represent an important step towards the rational design of CYP4Z1 prodrugs and guide further investigations into the so far poorly understood physiological role of CYP4Z1.

[160]

M. Dumitrascuta, M. Bermudez, S. Ballet, G. Wolber, and M. Spetea. Mechanistic understanding of peptide analogues, dalda, [Dmt1]DALDA, and KGOP01, binding to the µ opioid receptor, Molecules, 25(9):2087, 2020.
Links: [doi:10.3390/molecules25092087] [show BibTeX] [show abstract]  x  @article{RN285, author = {Dumitrascuta, M. and Bermudez, M. and Ballet, S. and Wolber, G. and Spetea, M.}, title = {Mechanistic understanding of peptide analogues, dalda, [Dmt1]DALDA, and KGOP01, binding to the µ opioid receptor}, journal = {Molecules}, volume = {25}, number = {9}, pages = {2087}, note = {Lr4vz Times Cited:2 Cited References Count:52}, abstract = {The mu opioid receptor (MOR) is the primary target for analgesia of endogenous opioid peptides, alkaloids, synthetic small molecules with diverse scaffolds, and peptidomimetics. Peptide-based opioids are viewed as potential analgesics with reduced side effects and have received constant scientific interest over the years. This study focuses on three potent peptide and peptidomimetic MOR agonists, DALDA, [Dmt(1)]DALDA, and KGOP01, and the prototypical peptide MOR agonist DAMGO. We present the first molecular modeling study and structure-activity relationships aided by in vitro assays and molecular docking of the opioid peptide analogues, in order to gain insight into their mode of binding to the MOR. In vitro binding and functional assays revealed the same rank order with KGOP01 [Dmt(1)]DALDA DAMGO DALDA for both binding and MOR activation. Using molecular docking at the MOR and three-dimensional interaction pattern analysis, we have rationalized the experimental outcomes and highlighted key amino acid residues responsible for agonist binding to the MOR. The Dmt (2 ',6 '-dimethyl-L-Tyr) moiety of [Dmt(1)]DALDA and KGOP01 was found to represent the driving force for their high potency and agonist activity at the MOR. These findings contribute to a deeper understanding of MOR function and flexible peptide ligand-MOR interactions, that are of significant relevance for the future design of opioid peptide-based analgesics.}, keywords = {mu opioid receptor opioid peptides and peptidomimetics damgo dalda [dmt(1)]dalda kgop01 binding molecular docking structure-activity relationships in-vitro potent pharmacology h-dmt-d-arg-phe-lys-nh2 activation ligands agonist}, ISSN = {1420-3049 (Electronic) 1420-3049 (Linking)}, DOI = {10.3390/molecules25092087}, url = {Go to ISI://WOS:000535695900083 https://res.mdpi.com/d_attachment/molecules/molecules-25-02087/article_deploy/molecules-25-02087-v2.pdf}, year = {2020}, type = {Journal Article} }  x  Mechanistic understanding of peptide analogues, dalda, [Dmt1]DALDA, and KGOP01, binding to the µ opioid receptor

The mu opioid receptor (MOR) is the primary target for analgesia of endogenous opioid peptides, alkaloids, synthetic small molecules with diverse scaffolds, and peptidomimetics. Peptide-based opioids are viewed as potential analgesics with reduced side effects and have received constant scientific interest over the years. This study focuses on three potent peptide and peptidomimetic MOR agonists, DALDA, [Dmt(1)]DALDA, and KGOP01, and the prototypical peptide MOR agonist DAMGO. We present the first molecular modeling study and structure-activity relationships aided by in vitro assays and molecular docking of the opioid peptide analogues, in order to gain insight into their mode of binding to the MOR. In vitro binding and functional assays revealed the same rank order with KGOP01 > [Dmt(1)]DALDA > DAMGO > DALDA for both binding and MOR activation. Using molecular docking at the MOR and three-dimensional interaction pattern analysis, we have rationalized the experimental outcomes and highlighted key amino acid residues responsible for agonist binding to the MOR. The Dmt (2 ',6 '-dimethyl-L-Tyr) moiety of [Dmt(1)]DALDA and KGOP01 was found to represent the driving force for their high potency and agonist activity at the MOR. These findings contribute to a deeper understanding of MOR function and flexible peptide ligand-MOR interactions, that are of significant relevance for the future design of opioid peptide-based analgesics.

[159]

M. Dumitrascuta, M. Bermudez, T. Ben Haddou, E. Guerrieri, L. Schlafer, A. Ritsch, S. Hosztafi, A. Lantero, C. Kreutz, D. Massotte, H. Schmidhammer, G. Wolber, and M. Spetea. N-phenethyl substitution in 14-methoxy-n-methylmorphinan-6-ones turns selective mu opioid receptor ligands into dual µ/δ opioid receptor agonists, Scientific Reports, 10(1):5653, 2020.
Links: [doi:10.1038/s41598-020-62530-w] [show BibTeX] [show abstract]  x  @article{RN290, author = {Dumitrascuta, M. and Bermudez, M. and Ben Haddou, T. and Guerrieri, E. and Schlafer, L. and Ritsch, A. and Hosztafi, S. and Lantero, A. and Kreutz, C. and Massotte, D. and Schmidhammer, H. and Wolber, G. and Spetea, M.}, title = {N-phenethyl substitution in 14-methoxy-n-methylmorphinan-6-ones turns selective mu opioid receptor ligands into dual µ/δ opioid receptor agonists}, journal = {Scientific Reports}, volume = {10}, number = {1}, pages = {5653}, note = {Nb3it Times Cited:1 Cited References Count:56}, abstract = {Morphine and structurally-derived compounds are mu opioid receptor (mu OR) agonists, and the most effective analgesic drugs. However, their usefulness is limited by serious side effects, including dependence and abuse potential. The N-substituent in morphinans plays an important role in opioid activities in vitro and in vivo. This study presents the synthesis and pharmacological evaluation of new N-phenethyl substituted 14-O-methylmorphinan-6-ones. Whereas substitution of the N-methyl substituent in morphine (1) and oxymorphone (2) by an N-phenethyl group enhances binding affinity, selectivity and agonist potency at the mu OR of 1a and 2a, the N-phenethyl substitution in 14-methoxy-N-methylmorphinan-6-ones (3 and 4) converts selective mu OR ligands into dual mu/delta OR agonists (3a and 4a). Contrary to N-methylmorphinans 1-4, the N-phenethyl substituted morphinans 1a-4a produce effective and potent antinociception without motor impairment in mice. Using docking and molecular dynamics simulations with the mu OR, we establish that N-methylmorphinans 1-4 and their N-phenethyl counterparts 1a-4a share several essential receptor-ligand interactions, but also interaction pattern differences related to specific structural features, thus providing a structural basis for their pharmacological profiles. The emerged structure-activity relationships in this class of morphinans provide important information for tuning in vitro and in vivo opioid activities towards discovery of effective and safer analgesics.}, keywords = {biological evaluation delta-agonists highly potent 14-alkoxymorphinans derivatives analgesics 14-methoxymetopon antagonism tolerance 14-alkoxy}, ISSN = {2045-2322}, DOI = {10.1038/s41598-020-62530-w}, url = {Go to ISI://WOS:000560409100007 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7101422/pdf/41598_2020_Article_62530.pdf}, year = {2020}, type = {Journal Article} }  x  N-phenethyl substitution in 14-methoxy-n-methylmorphinan-6-ones turns selective mu opioid receptor ligands into dual µ/δ opioid receptor agonists

Morphine and structurally-derived compounds are mu opioid receptor (mu OR) agonists, and the most effective analgesic drugs. However, their usefulness is limited by serious side effects, including dependence and abuse potential. The N-substituent in morphinans plays an important role in opioid activities in vitro and in vivo. This study presents the synthesis and pharmacological evaluation of new N-phenethyl substituted 14-O-methylmorphinan-6-ones. Whereas substitution of the N-methyl substituent in morphine (1) and oxymorphone (2) by an N-phenethyl group enhances binding affinity, selectivity and agonist potency at the mu OR of 1a and 2a, the N-phenethyl substitution in 14-methoxy-N-methylmorphinan-6-ones (3 and 4) converts selective mu OR ligands into dual mu/delta OR agonists (3a and 4a). Contrary to N-methylmorphinans 1-4, the N-phenethyl substituted morphinans 1a-4a produce effective and potent antinociception without motor impairment in mice. Using docking and molecular dynamics simulations with the mu OR, we establish that N-methylmorphinans 1-4 and their N-phenethyl counterparts 1a-4a share several essential receptor-ligand interactions, but also interaction pattern differences related to specific structural features, thus providing a structural basis for their pharmacological profiles. The emerged structure-activity relationships in this class of morphinans provide important information for tuning in vitro and in vivo opioid activities towards discovery of effective and safer analgesics.

[158]

M. T. Gabr, D. Machalz, S. Pach, and G. Wolber. A benzoxazole derivative as an inhibitor of anaerobic choline metabolism by human gut microbiota, RSC Medicinal Chemistry, 11(12):1402-1412, 2020.
Links: [doi:10.1039/D0MD00218F] [show BibTeX] [show abstract]  x  @article{RN298, author = {Gabr, Moustafa T. and Machalz, David and Pach, Szymon and Wolber, Gerhard}, title = {A benzoxazole derivative as an inhibitor of anaerobic choline metabolism by human gut microbiota}, journal = {RSC Medicinal Chemistry}, volume = {11}, number = {12}, pages = {1402-1412}, note = {Pg4qx Times Cited:0 Cited References Count:65}, abstract = {Metabolic pathways mediated by human gut bacteria have emerged as potential therapeutic targets because of their association with the pathophysiology of various human diseases. The anaerobic transformation of choline into trimethylamine (TMA) by gut microbiota is directly linked to type 2 diabetes, fatty liver disease, and cardiovascular diseases. Structural analogs of choline have been developed as competitive inhibitors of choline TMA-lyase (CutC), a key enzyme for the conversion of choline to TMA. However, weak to moderate CutC inhibitory profiles of the choline analogs limit their further advancement into clinical translation. In this study, we introduce a glycomimetic-based approach for the identification of CutC inhibitors with intestinal metabolic stability. Our workflow started with screening of a small library of glycomimetics for metabolic stability in the presence of human intestinal S9 fraction. Further screening using an in vitro CutC inhibitory assay identified a benzoxazole ligand (BO-I) as a CutC inhibitor with an IC50 value of 2.4 ± 0.3 μM. Kinetic analysis revealed that BO-I functions as a non-competitive inhibitor of CutC. Interestingly, BO-I reduced the production of TMA in whole cell assays of multiple bacterial strains as well as in complex biological environments. Therefore, structural optimization of BO-I holds promise for the development of efficient gut microbiota-targeted small molecules.}, keywords = {trimethylamine n-oxide drug-metabolism monooxygenase 3 health glycomimetics chemistry impact lyase fmo3}, DOI = {10.1039/D0MD00218F}, url = {http://dx.doi.org/10.1039/D0MD00218F https://pubs.rsc.org/en/content/articlepdf/2020/md/d0md00218f}, year = {2020}, type = {Journal Article} }  x  A benzoxazole derivative as an inhibitor of anaerobic choline metabolism by human gut microbiota

Metabolic pathways mediated by human gut bacteria have emerged as potential therapeutic targets because of their association with the pathophysiology of various human diseases. The anaerobic transformation of choline into trimethylamine (TMA) by gut microbiota is directly linked to type 2 diabetes, fatty liver disease, and cardiovascular diseases. Structural analogs of choline have been developed as competitive inhibitors of choline TMA-lyase (CutC), a key enzyme for the conversion of choline to TMA. However, weak to moderate CutC inhibitory profiles of the choline analogs limit their further advancement into clinical translation. In this study, we introduce a glycomimetic-based approach for the identification of CutC inhibitors with intestinal metabolic stability. Our workflow started with screening of a small library of glycomimetics for metabolic stability in the presence of human intestinal S9 fraction. Further screening using an in vitro CutC inhibitory assay identified a benzoxazole ligand (BO-I) as a CutC inhibitor with an IC50 value of 2.4 ± 0.3 μM. Kinetic analysis revealed that BO-I functions as a non-competitive inhibitor of CutC. Interestingly, BO-I reduced the production of TMA in whole cell assays of multiple bacterial strains as well as in complex biological environments. Therefore, structural optimization of BO-I holds promise for the development of efficient gut microbiota-targeted small molecules.

[157]

M. Grabowski, M. Bermudez, T. Rudolf, D. Sribar, P. Varga, M. S. Murgueitio, G. Wolber, J. Rademann, and G. Weindl. Identification and validation of a novel dual small-molecule TLR2/8 antagonist, Biochem Pharmacol, 177:113957, 2020.
Links: [doi:10.1016/j.bcp.2020.113957] [show BibTeX] [show abstract]  x  @article{RN283, author = {Grabowski, M. and Bermudez, M. and Rudolf, T. and Sribar, D. and Varga, P. and Murgueitio, M. S. and Wolber, G. and Rademann, J. and Weindl, G.}, title = {Identification and validation of a novel dual small-molecule TLR2/8 antagonist}, journal = {Biochemical Pharmacology}, volume = {177}, pages = {113957}, note = {Lz5eu Times Cited:0 Cited References Count:61}, abstract = {Toll-like receptor 2 (TLR2) and TLR8 are involved in the recognition of bacterial and viral components and are linked not only to protective antimicrobial immunity but also to inflammatory diseases. Recently, increasing attention has been paid to the receptor crosstalk between TLR2 and TLR8 to fine-tune innate immune responses. In this study, we report a novel dual TLR2/TLR8 antagonist, compound 24 that was developed by a modeling-guided synthesis approach. The modulator was optimized from the previously reported 1,3-benzothiazole derivative, compound 8. Compound 24 was pharmacologically characterized for the ability to inhibit TLR2- and TLR8-mediated responses in TLR-overexpressing reporter cells and THP-1 macrophages. The modulator showed high efficacy with IC50, values in the low micromolar range for both TLR5, selectivity towards other TLR5 and low cytotoxicity. At TLR2, a slight predominance for the TLR2/1 heterodimer was found in reporter cells selectively expressing TLR2/1 or TLR2/6 heterodimers. Concentration ratio analysis in the presence of Pam(3)CSK(4) or Pam(2)CSK(4) indicated non-competitive antagonist behavior at hTLR2. In computational docking studies, a plausible alternative binding mode of compound 24 was predicted for both TLR2 and TLR8. Our results provide evidence that it is feasible to simultaneously and selectively target endosomal- and surface-located TLR5. We identified a small-molecule dual TLR2/8 antagonist that may serve as a valuable pharmacological tool to decipher the role of TLR2/8 co-signaling in inflammation.}, keywords = {drug discovery computer modeling toll-like receptor (tlr) innate immunity inflammation virtual screening dual antagonist non-competitive antagonism toll-like receptors human monocytes bacterial rna human tlr8 recognition polymorphisms cooperation inhibition mechanisms peptides}, ISSN = {0006-2952}, DOI = {10.1016/j.bcp.2020.113957}, url = {Go to ISI://WOS:000541248000032 https://www.sciencedirect.com/science/article/abs/pii/S0006295220301854?via%3Dihub}, year = {2020}, type = {Journal Article} }  x  Identification and validation of a novel dual small-molecule TLR2/8 antagonist

Toll-like receptor 2 (TLR2) and TLR8 are involved in the recognition of bacterial and viral components and are linked not only to protective antimicrobial immunity but also to inflammatory diseases. Recently, increasing attention has been paid to the receptor crosstalk between TLR2 and TLR8 to fine-tune innate immune responses. In this study, we report a novel dual TLR2/TLR8 antagonist, compound 24 that was developed by a modeling-guided synthesis approach. The modulator was optimized from the previously reported 1,3-benzothiazole derivative, compound 8. Compound 24 was pharmacologically characterized for the ability to inhibit TLR2- and TLR8-mediated responses in TLR-overexpressing reporter cells and THP-1 macrophages. The modulator showed high efficacy with IC50, values in the low micromolar range for both TLR5, selectivity towards other TLR5 and low cytotoxicity. At TLR2, a slight predominance for the TLR2/1 heterodimer was found in reporter cells selectively expressing TLR2/1 or TLR2/6 heterodimers. Concentration ratio analysis in the presence of Pam(3)CSK(4) or Pam(2)CSK(4) indicated non-competitive antagonist behavior at hTLR2. In computational docking studies, a plausible alternative binding mode of compound 24 was predicted for both TLR2 and TLR8. Our results provide evidence that it is feasible to simultaneously and selectively target endosomal- and surface-located TLR5. We identified a small-molecule dual TLR2/8 antagonist that may serve as a valuable pharmacological tool to decipher the role of TLR2/8 co-signaling in inflammation.

[156]

M. Grabowski, M. S. Murgueitio, M. Bermudez, G. Wolber, and G. Weindl. The novel small-molecule antagonist MMG-11 preferentially inhibits TLR2/1 signaling, Biochem Pharmacol, 171:113687, 2020.
Links: [doi:10.1016/j.bcp.2019.113687] [show BibTeX] [show abstract]  x  @article{RN279, author = {Grabowski, Maria and Murgueitio, Manuela S. and Bermudez, Marcel and Wolber, Gerhard and Weindl, Günther}, title = {The novel small-molecule antagonist MMG-11 preferentially inhibits TLR2/1 signaling}, journal = {Biochemical Pharmacology}, volume = {171}, pages = {113687}, abstract = {Toll-like receptor 2 (TLR2) forms heterodimers with either TLR1 or TLR6 to induce protective early inflammatory responses to pathogen- and damage-associated molecular patterns. However, excessive activation is associated with inflammatory and metabolic diseases. Several TLR2 antagonists have been described but pharmacological characterization is still at an early stage. Previously, we identified the potent and selective TLR2 antagonist MMG-11 by computational modelling and experimental validation. Here, we characterized the TLR2 antagonists MMG-11 and CU-CPT22 as well as the TIR-domain binding TLR2 antagonist C29 in TLR-overexpressing promoter cells as well as human and mouse macrophages. In line with our recent studies, MMG-11 abrogated pro-inflammatory cytokine secretion and NF-κB activation induced by different bacterial TLR2 agonists. MMG-11 preferentially inhibited TLR2/1 signaling in promoter cells stably expressing TLR2 heterodimers and mouse macrophages. Furthermore, the TLR2 antagonist blocked ligand-induced interaction of TLR2 with MyD88 and reduced MAP kinase and NF-κB activation. MMG-11 and CU-CPT22 but not C29 displaced Pam3CSK4 in an indirect binding assay confirming the competitive mode of action of MMG-11 and CU-CPT22. Isobologram analysis revealed additive and synergistic effects when the non-competitive antagonist C29 was combined with the competitive antagonist MMG-11 or CU-CPT22, respectively. In conclusion, we provide evidence that MMG-11 acts as a competitive antagonist with a predominance for the TLR2/1 heterodimer in human and mouse cells. Our results also indicate that MMG-11 is a model compound for studying TLR2 signaling.}, keywords = {Inflammation Innate immunity Toll-like receptors TLR2 TLR2/1 heterodimer Competitive antagonist}, ISSN = {0006-2952}, DOI = {10.1016/j.bcp.2019.113687}, year = {2020}, type = {Journal Article} }  x  The novel small-molecule antagonist MMG-11 preferentially inhibits TLR2/1 signaling

Toll-like receptor 2 (TLR2) forms heterodimers with either TLR1 or TLR6 to induce protective early inflammatory responses to pathogen- and damage-associated molecular patterns. However, excessive activation is associated with inflammatory and metabolic diseases. Several TLR2 antagonists have been described but pharmacological characterization is still at an early stage. Previously, we identified the potent and selective TLR2 antagonist MMG-11 by computational modelling and experimental validation. Here, we characterized the TLR2 antagonists MMG-11 and CU-CPT22 as well as the TIR-domain binding TLR2 antagonist C29 in TLR-overexpressing promoter cells as well as human and mouse macrophages. In line with our recent studies, MMG-11 abrogated pro-inflammatory cytokine secretion and NF-κB activation induced by different bacterial TLR2 agonists. MMG-11 preferentially inhibited TLR2/1 signaling in promoter cells stably expressing TLR2 heterodimers and mouse macrophages. Furthermore, the TLR2 antagonist blocked ligand-induced interaction of TLR2 with MyD88 and reduced MAP kinase and NF-κB activation. MMG-11 and CU-CPT22 but not C29 displaced Pam3CSK4 in an indirect binding assay confirming the competitive mode of action of MMG-11 and CU-CPT22. Isobologram analysis revealed additive and synergistic effects when the non-competitive antagonist C29 was combined with the competitive antagonist MMG-11 or CU-CPT22, respectively. In conclusion, we provide evidence that MMG-11 acts as a competitive antagonist with a predominance for the TLR2/1 heterodimer in human and mouse cells. Our results also indicate that MMG-11 is a model compound for studying TLR2 signaling.

[155]

J. Holze, M. Bermudez, E. M. Pfeil, M. Kauk, T. Bödefeld, M. Irmen, C. Matera, C. Dallanoce, M. De Amici, U. Holzgrabe, G. M. König, C. Tränkle, G. Wolber, R. Schrage, K. Mohr, C. Hoffmann, E. Kostenis, and A. Bock. Ligand-specific allosteric coupling controls G-Protein-Coupled receptor signaling, ACS Pharmacology & Translational Science, 3(5):859-867, 2020.
Links: [doi:10.1021/acsptsci.0c00069] [show BibTeX] [show abstract]  x  @article{RN296, author = {Holze, Janine and Bermudez, Marcel and Pfeil, Eva Marie and Kauk, Michael and Bödefeld, Theresa and Irmen, Matthias and Matera, Carlo and Dallanoce, Clelia and De Amici, Marco and Holzgrabe, Ulrike and König, Gabriele Maria and Tränkle, Christian and Wolber, Gerhard and Schrage, Ramona and Mohr, Klaus and Hoffmann, Carsten and Kostenis, Evi and Bock, Andreas}, title = {Ligand-specific allosteric coupling controls G-Protein-Coupled receptor signaling}, journal = {ACS Pharmacology & Translational Science}, volume = {3}, number = {5}, pages = {859-867}, abstract = {Allosteric coupling describes a reciprocal process whereby G-protein-coupled receptors (GPCRs) relay ligand-induced conformational changes from the extracellular binding pocket to the intracellular signaling surface. Therefore, GPCR activation is sensitive to both the type of extracellular ligand and intracellular signaling protein. We hypothesized that ligand-specific allosteric coupling may result in preferential (i.e., biased) engagement of downstream effectors. However, the structural basis underlying ligand-dependent control of this essential allosteric mechanism is poorly understood. Here, we show that two sets of extended muscarinic acetylcholine receptor M1 agonists, which only differ in linker length, progressively constrain receptor signaling. We demonstrate that stepwise shortening of their chemical linker gradually hampers binding pocket closure, resulting in divergent coupling to distinct G-protein families. Our data provide an experimental strategy for the design of ligands with selective G-protein recognition and reveal a potentially general mechanism of ligand-specific allosteric coupling.}, DOI = {10.1021/acsptsci.0c00069}, url = {https://doi.org/10.1021/acsptsci.0c00069 https://pubs.acs.org/doi/pdf/10.1021/acsptsci.0c00069}, year = {2020}, type = {Journal Article} }  x  Ligand-specific allosteric coupling controls G-Protein-Coupled receptor signaling

Allosteric coupling describes a reciprocal process whereby G-protein-coupled receptors (GPCRs) relay ligand-induced conformational changes from the extracellular binding pocket to the intracellular signaling surface. Therefore, GPCR activation is sensitive to both the type of extracellular ligand and intracellular signaling protein. We hypothesized that ligand-specific allosteric coupling may result in preferential (i.e., biased) engagement of downstream effectors. However, the structural basis underlying ligand-dependent control of this essential allosteric mechanism is poorly understood. Here, we show that two sets of extended muscarinic acetylcholine receptor M1 agonists, which only differ in linker length, progressively constrain receptor signaling. We demonstrate that stepwise shortening of their chemical linker gradually hampers binding pocket closure, resulting in divergent coupling to distinct G-protein families. Our data provide an experimental strategy for the design of ligands with selective G-protein recognition and reveal a potentially general mechanism of ligand-specific allosteric coupling.

[154]

K. B. Loboda, K. Valjavec, M. Štampar, G. Wolber, B. Žegura, M. Filipič, M. S. Dolenc, and A. Perdih. Design and synthesis of 3,5-substituted 1,2,4-oxadiazoles as catalytic inhibitors of human DNA topoisomerase IIα, Bioorg Chem, 99:103828, 2020.
Links: [doi:10.1016/j.bioorg.2020.103828] [show BibTeX] [show abstract]  x  @article{RN297, author = {Loboda, Kaja Bergant and Valjavec, Katja and Štampar, Martina and Wolber, Gerhard and Žegura, Bojana and Filipič, Metka and Dolenc, Marija Sollner and Perdih, Andrej}, title = {Design and synthesis of 3,5-substituted 1,2,4-oxadiazoles as catalytic inhibitors of human DNA topoisomerase IIα}, journal = {Bioorganic Chemistry}, volume = {99}, pages = {103828}, abstract = {Cancer constitutes a group of diseases linked to abnormal cell growth that can potentially spread to other parts of the body and is one of the most common causes of death. The molecular motors - DNA topoisomerases - that enable topological changes of the DNA molecule are one of the most established targets of cancer therapies. Due to known limitations of established topo II poisons such as cardiotoxicity, induction of secondary malignancies and recognized cancer cell resistance, an emerging group of catalytic topo II inhibitors attempts to circumvent these challenges. Currently, this approach comprises several subgroups of mechanistically diverse inhibitors, one of which are compounds that act by binding to their ATPase domain. In this study we have designed, synthesized and characterized a new series of 3,5-substituted 1,2,4-oxadiazoles that act as catalytic inhibitors of human topo IIα. The introduction of the substituted rigid substitutions on the oxadiazole backbone was intended to enhance the interactions with the ATP binding site. In the inhibition assays selected compounds revealed a new class of catalytic inhibitors targeting this molecular motor and showed binding to the isolated topo IIα ATPase domain. The predicted inhibitor binding geometries were evaluated in molecular dynamics simulations and subsequently dynophore models were derived, which provided a deeper insight into molecular recognition with its macromolecular target. Selected compounds also displayed in vitro cytotoxicity on the investigated MCF-7 cancer cell line and did not induce double-strand breaks (DSB), thus displaying a mechanism of action diverse from the topo II poisons also on the cellular level. The substituted oxadiazoles thus comprise a chemical class of interesting compounds that are synthetically fully amenable for further optimization to anticancer drugs.}, keywords = {Human DNA topoisomerase IIα Catalytic inhibitors Drug design Oxadiazoles Anticancer agents}, ISSN = {0045-2068}, DOI = {10.1016/j.bioorg.2020.103828}, url = {http://www.sciencedirect.com/science/article/pii/S0045206820301218 https://www.sciencedirect.com/science/article/abs/pii/S0045206820301218?via%3Dihub}, year = {2020}, type = {Journal Article} }  x  Design and synthesis of 3,5-substituted 1,2,4-oxadiazoles as catalytic inhibitors of human DNA topoisomerase IIα

Cancer constitutes a group of diseases linked to abnormal cell growth that can potentially spread to other parts of the body and is one of the most common causes of death. The molecular motors - DNA topoisomerases - that enable topological changes of the DNA molecule are one of the most established targets of cancer therapies. Due to known limitations of established topo II poisons such as cardiotoxicity, induction of secondary malignancies and recognized cancer cell resistance, an emerging group of catalytic topo II inhibitors attempts to circumvent these challenges. Currently, this approach comprises several subgroups of mechanistically diverse inhibitors, one of which are compounds that act by binding to their ATPase domain. In this study we have designed, synthesized and characterized a new series of 3,5-substituted 1,2,4-oxadiazoles that act as catalytic inhibitors of human topo IIα. The introduction of the substituted rigid substitutions on the oxadiazole backbone was intended to enhance the interactions with the ATP binding site. In the inhibition assays selected compounds revealed a new class of catalytic inhibitors targeting this molecular motor and showed binding to the isolated topo IIα ATPase domain. The predicted inhibitor binding geometries were evaluated in molecular dynamics simulations and subsequently dynophore models were derived, which provided a deeper insight into molecular recognition with its macromolecular target. Selected compounds also displayed in vitro cytotoxicity on the investigated MCF-7 cancer cell line and did not induce double-strand breaks (DSB), thus displaying a mechanism of action diverse from the topo II poisons also on the cellular level. The substituted oxadiazoles thus comprise a chemical class of interesting compounds that are synthetically fully amenable for further optimization to anticancer drugs.

[153]

S. Pach, T. M. Sarter, R. Yousef, D. Schaller, S. Bergemann, C. Arkona, J. Rademann, C. Nitsche, and G. Wolber. Catching a moving target: comparative modeling of flaviviral NS2B-NS3 reveals small molecule Zika protease inhibitors, ACS Medicinal Chemistry Letters, 11(4):514-520, 2020.
Links: [doi:10.1021/acsmedchemlett.9b00629] [show BibTeX] [show abstract]  x  @article{RN287, author = {Pach, S. and Sarter, T. M. and Yousef, R. and Schaller, D. and Bergemann, S. and Arkona, C. and Rademann, J. and Nitsche, C. and Wolber, G.}, title = {Catching a moving target: comparative modeling of flaviviral NS2B-NS3 reveals small molecule Zika protease inhibitors}, journal = {ACS Medicinal Chemistry Letters}, volume = {11}, number = {4}, pages = {514-520}, note = {Le0gi Times Cited:1 Cited References Count:48}, abstract = {The pivotal role of viral proteases in virus replication has already been successfully exploited in several antiviral drug design campaigns. However, no efficient antivirals are currently available against flaviviral infections. In this study, we present lead-like small molecule inhibitors of the Zika Virus (ZIKV) NS2B-NS3 protease. Since only few nonpeptide competitive ligands are known, we take advantage of the high structural similarity with the West Nile Virus (WNV) NS2B-NS3 protease. A comparative modeling approach involving our in-house software PyRod was employed to systematically analyze the binding sites and develop molecular dynamics-based 3D pharmacophores for virtual screening. The identified compounds were biochemically characterized revealing low micromolar affinity for both ZIKV and WNV proteases. Their lead-like properties together with rationalized binding modes represent valuable starting points for future lead optimization. Since the NS2B-NS3 protease is highly conserved among flaviviruses, these compounds may also drive the development of pan-flaviviral antiviral drugs.}, keywords = {flavivirus protease inhibitors pyrod 3d pharmacophores dynophores virus ns3 protease serine-protease in-vitro dengue identification vaccine mutagenesis discovery progress ligands}, ISSN = {1948-5875}, DOI = {10.1021/acsmedchemlett.9b00629}, url = {Go to ISI://WOS:000526402700018 https://pubs.acs.org/doi/pdf/10.1021/acsmedchemlett.9b00629}, year = {2020}, type = {Journal Article} }  x  Catching a moving target: comparative modeling of flaviviral NS2B-NS3 reveals small molecule Zika protease inhibitors

The pivotal role of viral proteases in virus replication has already been successfully exploited in several antiviral drug design campaigns. However, no efficient antivirals are currently available against flaviviral infections. In this study, we present lead-like small molecule inhibitors of the Zika Virus (ZIKV) NS2B-NS3 protease. Since only few nonpeptide competitive ligands are known, we take advantage of the high structural similarity with the West Nile Virus (WNV) NS2B-NS3 protease. A comparative modeling approach involving our in-house software PyRod was employed to systematically analyze the binding sites and develop molecular dynamics-based 3D pharmacophores for virtual screening. The identified compounds were biochemically characterized revealing low micromolar affinity for both ZIKV and WNV proteases. Their lead-like properties together with rationalized binding modes represent valuable starting points for future lead optimization. Since the NS2B-NS3 protease is highly conserved among flaviviruses, these compounds may also drive the development of pan-flaviviral antiviral drugs.

[152]

D. Schaller, D. Sribar, T. Noonan, L. H. Deng, T. N. Nguyen, S. Pach, D. Machalz, M. Bermudez, and G. Wolber. Next generation 3D pharmacophore modeling, Wiley Interdisciplinary Reviews: Computational Molecular Science, 10(4):e1468, 2020.
Links: [doi:10.1002/wcms.1468] [show BibTeX] [show abstract]  x  @article{RN291, author = {Schaller, D. and Sribar, D. and Noonan, T. and Deng, L. H. and Nguyen, T. N. and Pach, S. and Machalz, D. and Bermudez, M. and Wolber, G.}, title = {Next generation 3D pharmacophore modeling}, journal = {Wiley Interdisciplinary Reviews: Computational Molecular Science}, volume = {10}, number = {4}, pages = {e1468}, note = {Mc0lp Times Cited:4 Cited References Count:111}, abstract = {3D pharmacophore models are three-dimensional ensembles of chemically defined interactions of a ligand in its bioactive conformation. They represent an elegant way to decipher chemically encoded ligand information and have therefore become a valuable tool in drug design. In this review, we provide an overview on the basic concept of this method and summarize key studies for applying 3D pharmacophore models in virtual screening and mechanistic studies for protein functionality. Moreover, we discuss recent developments in the field. The combination of 3D pharmacophore models with molecular dynamics simulations could be a quantum leap forward since these approaches consider macromolecule-ligand interactions as dynamic and therefore show a physiologically relevant interaction pattern. Other trends include the efficient usage of 3D pharmacophore information in machine learning and artificial intelligence applications or freely accessible web servers for 3D pharmacophore modeling. The recent developments show that 3D pharmacophore modeling is a vibrant field with various applications in drug discovery and beyond. This article is categorized under: Computer and Information Science Chemoinformatics Computer and Information Science Computer Algorithms and Programming Molecular and Statistical Mechanics Molecular Interactions}, keywords = {3d pharmacophores artifical intelligence machine learning virtual screening web services competitive saturation silcs drug discovery dynamics simulations site-identification covalent inhibitors chemical space protein binding design receptor}, ISSN = {1759-0876}, DOI = {10.1002/wcms.1468}, url = {Go to ISI://WOS:000516132600001 https://onlinelibrary.wiley.com/doi/pdfdirect/10.1002/wcms.1468?download= true}, year = {2020}, type = {Journal Article} }  x  Next generation 3D pharmacophore modeling

3D pharmacophore models are three-dimensional ensembles of chemically defined interactions of a ligand in its bioactive conformation. They represent an elegant way to decipher chemically encoded ligand information and have therefore become a valuable tool in drug design. In this review, we provide an overview on the basic concept of this method and summarize key studies for applying 3D pharmacophore models in virtual screening and mechanistic studies for protein functionality. Moreover, we discuss recent developments in the field. The combination of 3D pharmacophore models with molecular dynamics simulations could be a quantum leap forward since these approaches consider macromolecule-ligand interactions as dynamic and therefore show a physiologically relevant interaction pattern. Other trends include the efficient usage of 3D pharmacophore information in machine learning and artificial intelligence applications or freely accessible web servers for 3D pharmacophore modeling. The recent developments show that 3D pharmacophore modeling is a vibrant field with various applications in drug discovery and beyond. This article is categorized under: Computer and Information Science > Chemoinformatics Computer and Information Science > Computer Algorithms and Programming Molecular and Statistical Mechanics > Molecular Interactions

[151]

D. Schaller, and G. Wolber. Pyrod enables rational homology model-based virtual screening against MCHR1, Mol Inf, 39(6):e2000020, 2020.
Links: [doi:10.1002/minf.202000020] [show BibTeX] [show abstract]  x  @article{RN286, author = {Schaller, D. and Wolber, G.}, title = {Pyrod enables rational homology model-based virtual screening against MCHR1}, journal = {Molecular Informatics}, volume = {39}, number = {6}, pages = {e2000020}, note = {Lv0tp Times Cited:0 Cited References Count:40}, abstract = {Several encouraging pre-clinical results highlight the melanin-concentrating hormone receptor 1 (MCHR1) as promising target for anti-obesity drug development. Currently however, experimentally resolved structures of MCHR1 are not available, which complicates rational drug design campaigns. In this study, we aimed at developing accurate, homologymodel-based 3D pharmacophores against MCHR1. We show that traditional approaches involving docking of known active small molecules are hindered by the flexibility of binding pocket residues. Instead, we derived three-dimensional pharmacophores from molecular dynamics simulations by employing our novel open-source software PyRod. In a retrospective evaluation, the generated 3D pharmacophores were highly predictive returning up to 35 % of active molecules and showing an early enrichment (EF1) of up to 27.6. Furthermore, PyRod pharmacophores demonstrate higher sensitivity than ligand-based pharmacophores and deliver structural insights, which are key to rational lead optimization.}, keywords = {mchr1 pyrod 3d pharmacophore homology modeling md simulation protein dynamics database ligands system diet}, ISSN = {1868-1743}, DOI = {10.1002/minf.202000020}, url = {Go to ISI://WOS:000529246800001 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7317519/pdf/MINF-39-2000020.pdf}, year = {2020}, type = {Journal Article} }  x  Pyrod enables rational homology model-based virtual screening against MCHR1

Several encouraging pre-clinical results highlight the melanin-concentrating hormone receptor 1 (MCHR1) as promising target for anti-obesity drug development. Currently however, experimentally resolved structures of MCHR1 are not available, which complicates rational drug design campaigns. In this study, we aimed at developing accurate, homologymodel-based 3D pharmacophores against MCHR1. We show that traditional approaches involving docking of known active small molecules are hindered by the flexibility of binding pocket residues. Instead, we derived three-dimensional pharmacophores from molecular dynamics simulations by employing our novel open-source software PyRod. In a retrospective evaluation, the generated 3D pharmacophores were highly predictive returning up to 35 % of active molecules and showing an early enrichment (EF1) of up to 27.6. Furthermore, PyRod pharmacophores demonstrate higher sensitivity than ligand-based pharmacophores and deliver structural insights, which are key to rational lead optimization.

[150]

D. Stepanov, S. Canipa, and G. Wolber. HuskinDB, a database for skin permeation of xenobiotics, Scientific Data, 7(1):426, 2020.
Links: [doi:10.1038/s41597-020-00764-z] [show BibTeX] [show abstract]  x  @article{RN294, author = {Stepanov, Dmitri and Canipa, Steven and Wolber, Gerhard}, title = {HuskinDB, a database for skin permeation of xenobiotics}, journal = {Scientific Data}, volume = {7}, number = {1}, pages = {426}, abstract = {Skin permeation is an essential biological property of small organic compounds our body is exposed to, such as drugs in topic formulations, cosmetics, and environmental toxins. Despite the limited availability of experimental data, there is a lack of systematic analysis and structure. We present a novel resource on skin permeation data that collects all measurements available in the literature and systematically structures experimental conditions. Besides the skin permeation value kp, it includes experimental protocols such as skin source site, skin layer used, preparation technique, storage conditions, as well as test conditions such as temperature, pH as well as the type of donor and acceptor solution. It is important to include these parameters in the assessment of the skin permeation data. In addition, we provide an analysis of physicochemical properties and chemical space coverage, laying the basis for applicability domain determination of insights drawn from the collected data points. The database is freely accessible under https://huskindb.drug-design.deor https://doi.org/10.7303/syn21998881.}, ISSN = {2052-4463}, DOI = {10.1038/s41597-020-00764-z}, url = {https://doi.org/10.1038/s41597-020-00764-z https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7708619/pdf/41597_2020_Article_764.pdf}, year = {2020}, type = {Journal Article} }  x  HuskinDB, a database for skin permeation of xenobiotics

Skin permeation is an essential biological property of small organic compounds our body is exposed to, such as drugs in topic formulations, cosmetics, and environmental toxins. Despite the limited availability of experimental data, there is a lack of systematic analysis and structure. We present a novel resource on skin permeation data that collects all measurements available in the literature and systematically structures experimental conditions. Besides the skin permeation value kp, it includes experimental protocols such as skin source site, skin layer used, preparation technique, storage conditions, as well as test conditions such as temperature, pH as well as the type of donor and acceptor solution. It is important to include these parameters in the assessment of the skin permeation data. In addition, we provide an analysis of physicochemical properties and chemical space coverage, laying the basis for applicability domain determination of insights drawn from the collected data points. The database is freely accessible under https://huskindb.drug-design.deor https://doi.org/10.7303/syn21998881.

[149]

Y. Sun, D. Machalz, G. Wolber, M. K. Parr, and M. Bureik. Functional expression of all human sulfotransferases in fission yeast, assay development, and structural models for isoforms SULT4A1 and SULT6B1, Biomolecules, 10(11):1517, 2020.
Links: [doi:10.3390/biom10111517] [show BibTeX]  x  @article{RN295, author = {Sun, Yanan and Machalz, David and Wolber, Gerhard and Parr, Maria Kristina and Bureik, Matthias}, title = {Functional expression of all human sulfotransferases in fission yeast, assay development, and structural models for isoforms SULT4A1 and SULT6B1}, journal = {Biomolecules}, volume = {10}, number = {11}, pages = {1517}, ISSN = {2218-273X}, DOI = {10.3390/biom10111517}, url = {https://www.mdpi.com/2218-273X/10/11/1517 https://res.mdpi.com/d_attachment/biomolecules/biomolecules-10-01517/article_deploy/biomolecules-10-01517.pdf}, year = {2020}, type = {Journal Article} }

[148]

D. Volpato, M. Kauk, R. Messerer, M. Bermudez, G. Wolber, A. Bock, C. Hoffmann, and U. Holzgrabe. The role of orthosteric building blocks of bitopic ligands for muscarinic M1 receptors, ACS Omega, 5(49):31706-31715, 2020.
Links: [doi:10.1021/acsomega.0c04220] [show BibTeX] [show abstract]  x  @article{RN300, author = {Volpato, Daniela and Kauk, Michael and Messerer, Regina and Bermudez, Marcel and Wolber, Gerhard and Bock, Andreas and Hoffmann, Carsten and Holzgrabe, Ulrike}, title = {The role of orthosteric building blocks of bitopic ligands for muscarinic M1 receptors}, journal = {ACS Omega}, volume = {5}, number = {49}, pages = {31706-31715}, abstract = {The muscarinic M1 acetylcholine receptor is an important drug target for the treatment of various neurological disorders. Designing M1 receptor-selective drugs has proven challenging, mainly due to the high conservation of the acetylcholine binding site among muscarinic receptor subtypes. Therefore, less conserved and topographically distinct allosteric binding sites have been explored to increase M1 receptor selectivity. In this line, bitopic ligands, which target orthosteric and allosteric binding sites simultaneously, may provide a promising strategy. Here, we explore the allosteric, M1-selective BQCAd scaffold derived from BQCA as a starting point for the design, synthesis, and pharmacological evaluation of a series of novel bitopic ligands in which the orthosteric moieties and linker lengths are systematically varied. Since β-arrestin recruitment seems to be favorable to therapeutic implication, all the compounds were investigated by G protein and β-arrestin assays. Some bitopic ligands are partial to full agonists for G protein activation, some activate β-arrestin recruitment, and the degree of β-arrestin recruitment varies according to the respective modification. The allosteric BQCAd scaffold controls the positioning of the orthosteric ammonium group of all ligands, suggesting that this interaction is essential for stimulating G protein activation. However, β-arrestin recruitment is not affected. The novel set of bitopic ligands may constitute a toolbox to study the requirements of β-arrestin recruitment during ligand design for therapeutic usage.}, ISSN = {2470-1343}, DOI = {10.1021/acsomega.0c04220}, url = {https://doi.org/10.1021/acsomega.0c04220 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7745449/pdf/ao0c04220.pdf}, year = {2020}, type = {Journal Article} }  x  The role of orthosteric building blocks of bitopic ligands for muscarinic M1 receptors

The muscarinic M1 acetylcholine receptor is an important drug target for the treatment of various neurological disorders. Designing M1 receptor-selective drugs has proven challenging, mainly due to the high conservation of the acetylcholine binding site among muscarinic receptor subtypes. Therefore, less conserved and topographically distinct allosteric binding sites have been explored to increase M1 receptor selectivity. In this line, bitopic ligands, which target orthosteric and allosteric binding sites simultaneously, may provide a promising strategy. Here, we explore the allosteric, M1-selective BQCAd scaffold derived from BQCA as a starting point for the design, synthesis, and pharmacological evaluation of a series of novel bitopic ligands in which the orthosteric moieties and linker lengths are systematically varied. Since β-arrestin recruitment seems to be favorable to therapeutic implication, all the compounds were investigated by G protein and β-arrestin assays. Some bitopic ligands are partial to full agonists for G protein activation, some activate β-arrestin recruitment, and the degree of β-arrestin recruitment varies according to the respective modification. The allosteric BQCAd scaffold controls the positioning of the orthosteric ammonium group of all ligands, suggesting that this interaction is essential for stimulating G protein activation. However, β-arrestin recruitment is not affected. The novel set of bitopic ligands may constitute a toolbox to study the requirements of β-arrestin recruitment during ligand design for therapeutic usage.

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2019

[147]

L. Agnetta, M. Bermudez, F. Riefolo, C. Matera, E. Claro, R. Messerer, T. Littmann, G. Wolber, U. Holzgrabe, and M. Decker. Fluorination of photoswitchable muscarinic agonists tunes receptor pharmacology and photochromic properties, J Med Chem, 62(6):3009-3020, 2019.
Links: [doi:10.1021/acs.jmedchem.8b01822] [show BibTeX]  x  @article{RN264, author = {Agnetta, Luca and Bermudez, Marcel and Riefolo, Fabio and Matera, Carlo and Claro, Enrique and Messerer, Regina and Littmann, Timo and Wolber, Gerhard and Holzgrabe, Ulrike and Decker, Michael}, title = {Fluorination of photoswitchable muscarinic agonists tunes receptor pharmacology and photochromic properties}, journal = {Journal of Medicinal Chemistry}, volume = {62}, number = {6}, pages = {3009-3020}, keywords = {gpcr}, ISSN = {0022-2623}, DOI = {10.1021/acs.jmedchem.8b01822}, url = {https://doi.org/10.1021/acs.jmedchem.8b01822 https://pubs.acs.org/doi/pdfplus/10.1021/acs.jmedchem.8b01822}, year = {2019}, type = {Journal Article} }

[146]

H. Aygun Cevher, D. Schaller, M. A. Gandini, O. Kaplan, E. Gambeta, F. X. Zhang, M. Celebier, M. N. Tahir, G. W. Zamponi, G. Wolber, and M. G. Gunduz. Discovery of Michael acceptor containing 1,4-dihydropyridines as first covalent inhibitors of L-/T-type calcium channels, Bioorg Chem, 91:103187, 2019.
Links: [doi:10.1016/j.bioorg.2019.103187] [show BibTeX] [show abstract]  x  @article{RN276, author = {Aygun Cevher, H. and Schaller, D. and Gandini, M. A. and Kaplan, O. and Gambeta, E. and Zhang, F. X. and Celebier, M. and Tahir, M. N. and Zamponi, G. W. and Wolber, G. and Gunduz, M. G.}, title = {Discovery of Michael acceptor containing 1,4-dihydropyridines as first covalent inhibitors of L-/T-type calcium channels}, journal = {Bioorg Chem}, volume = {91}, pages = {103187}, note = {Aygun Cevher, Hande Schaller, David Gandini, Maria A Kaplan, Ozan Gambeta, Eder Zhang, Fang Xiong Celebier, Mustafa Tahir, Muhammad Nawaz Zamponi, Gerald W Wolber, Gerhard Gunduz, Miyase Gozde eng Bioorg Chem. 2019 Aug 7;91:103187. doi: 10.1016/j.bioorg.2019.103187.}, abstract = {1,4-Dihydropyridines (DHPs) are an important class of blockers targeting different calcium channel subtypes and have great therapeutic value against cardiovascular and neurophysiologic conditions. Here, we present the design of DHP-based hexahydroquinoline derivatives as either selective or covalent inhibitors of calcium channels. These compounds were synthesized via a modified Hantzsch reaction under microwave irradiation and characterized by IR, (1)H NMR, (13)C NMR and mass spectra. Additionally, the proposed structure of HM12 was resolved by single crystal X-ray analysis. The abilities of the target compounds to block both L- and T-type calcium channels were evaluated by utilizing the whole-cell patch clamp technique. Our results identified covalent inhibitors of calcium channels for the first time, which could be achieved by introducing a Michael acceptor group into the ester side chain of the compounds. The proposed covalent binding between the compounds and the cysteine amino acid (Cys1492) within the DHP binding pocket of L-type calcium channel was supported by docking and pharmacophore analysis as well as a glutathione reactivity assay.}, keywords = {Calcium channel blocker Covalent binding Dihydropyridine Hexahydroquinoline Molecular modeling Whole-cell patch clamp}, ISSN = {1090-2120 (Electronic) 0045-2068 (Linking)}, DOI = {10.1016/j.bioorg.2019.103187}, url = {https://www.ncbi.nlm.nih.gov/pubmed/31419643 https://www.sciencedirect.com/science/article/abs/pii/S0045206819309290?via%3Dihub}, year = {2019}, type = {Journal Article} }  x  Discovery of Michael acceptor containing 1,4-dihydropyridines as first covalent inhibitors of L-/T-type calcium channels

1,4-Dihydropyridines (DHPs) are an important class of blockers targeting different calcium channel subtypes and have great therapeutic value against cardiovascular and neurophysiologic conditions. Here, we present the design of DHP-based hexahydroquinoline derivatives as either selective or covalent inhibitors of calcium channels. These compounds were synthesized via a modified Hantzsch reaction under microwave irradiation and characterized by IR, (1)H NMR, (13)C NMR and mass spectra. Additionally, the proposed structure of HM12 was resolved by single crystal X-ray analysis. The abilities of the target compounds to block both L- and T-type calcium channels were evaluated by utilizing the whole-cell patch clamp technique. Our results identified covalent inhibitors of calcium channels for the first time, which could be achieved by introducing a Michael acceptor group into the ester side chain of the compounds. The proposed covalent binding between the compounds and the cysteine amino acid (Cys1492) within the DHP binding pocket of L-type calcium channel was supported by docking and pharmacophore analysis as well as a glutathione reactivity assay.

[145]

M. Bermudez, T. N. Nguyen, C. Omieczynski, and G. Wolber. Strategies for the discovery of biased GPCR ligands, Drug Discov Today, 24(4):1031-1037, 2019.
Links: [doi:10.1016/j.drudis.2019.02.010] [show BibTeX] [show abstract]  x  @article{RN267, author = {Bermudez, Marcel and Nguyen, Trung Ngoc and Omieczynski, Christian and Wolber, Gerhard}, title = {Strategies for the discovery of biased GPCR ligands}, journal = {Drug Discovery Today}, volume = {24}, number = {4}, pages = {1031-1037}, abstract = {G-protein-coupled receptors (GPCRs) represent important drug targets with complex pharmacological characteristics. Biased signaling represents one important dimension, describing ligand-dependent shifts of naturally imprinted signaling profiles. Because biased GPCR modulators provide potential therapeutic benefits including higher efficiencies and reduced adverse effects, the identification of such ligands as drug candidates is highly desirable. This review aims to provide an overview of the challenges and strategies in the discovery of biased ligands. We show different approaches for biased ligand discovery in the example of G-protein-biased opioid analgesics and discuss possibilities to design biased ligands by targeting extracellular receptor regions.}, keywords = {gpcr}, ISSN = {1359-6446}, DOI = {10.1016/j.drudis.2019.02.010}, url = {http://www.sciencedirect.com/science/article/pii/S1359644618302186 https://pdf.sciencedirectassets.com/271275/1-s2.0-S1359644619X00057/1-s2.0-S1359644618302186/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIBSuXR284U5c9bmAJSN5zVw47n5M5VTNwrBmGQ8hLXVcAiAWIgoCDAYq%2BrLMnoeOj0gcwMsJ%2BK2%2F2vx37jlwfG9V%2FiraAwhBEAIaDDA1OTAwMzU0Njg2NSIMjEBFMn9jIE9t1XN2KrcDLe7GRG%2FXcw3WEgKV9YXbSGYcHYB2z7r%2B9eRerOT0zpE0wRSFgQ%2FOH9BXlp37MIlzoDaMcVajFKZS8gcJXSICZZRdMHztkVCBW4DNZa%2BJxOwJ1E6Q6vzyyBGsc%2FRoV6Xba79A94ndoN8bYy6WNuplWyrl3mWsK2vv7sI6kqAQYvwZAuSo66P%2FLefOdgACsLXUvDUtMMpSN8TmoE6MAFh%2Fj9u1tN2PHd7Si9U0lR%2BPybWjyQIZhRLaPFiPA459dq%2F0DJYDW6PUXjnBlCqj2pjkDd8G%2FcrPGVCvjIs1dEukqNYRPh9wSQFFAb5Fi0wZV3zG%2F46Hc%2FeUQIprBOrsYtxFvQ1UWxSkaVfuuRD2NfJJC%2FoyWTyuxNmD0bdhukh9A21%2B1W83wJfu%2FecDVcxhN9MqXTDLroqrvl%2BRxWFnb%2BWbs%2B%2FV9bgL2cBI6AFt4X60UAEM%2FPSuYh%2FCMbaK1dtKiQLD4N%2F7kxQrpF%2BWzb6z4YOF5hW%2F4Jm%2BgH%2B0v9v9lego%2FcMGf98VdcRdShnMV0057mzmxPdKDL4AivAyKRRfnHrHbLoO1SdPlc41DKXR%2BjK0GtocjZ5j4aUAxDDnpo7rBTq1AThXMgqWLXhCysjiDb69KUDsmtirRuTrXpezLGPDfxkFp5ofIqWUR9J0yQNBLS%2BqlghqmfiGup4DJm90ED%2Bjr269Tuc2Ri4J0zfr7%2BcI1xixL%2Fy0rAQI30TJNbf1CsDGxfVixVDBG1Fkwa3KlpjjfAGAuGKaiPkPOMJuLo8YTbs28PVbbZSstkpcNX0npq661wJ6SM3c0BNDLzt2HCCzsKCoWT8MzDtnFnmY8Er2Z7ayg87lxx0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090852Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYZNRZYJFV%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=7f58eff199562319314a001e9580c09f4398c03f423e7fcb0c77abbe9f6e7b3f&hash=2eec85bc780a8441b8c56fa4d0c26581dfbc0117ea28d1b8a83af57b9cc39829&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S1359644618302186&tid=spdf-e17f4a4a-0e0c-4d81-94e3-c8ec97d2a8a8&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2019}, type = {Journal Article} }  x  Strategies for the discovery of biased GPCR ligands

G-protein-coupled receptors (GPCRs) represent important drug targets with complex pharmacological characteristics. Biased signaling represents one important dimension, describing ligand-dependent shifts of naturally imprinted signaling profiles. Because biased GPCR modulators provide potential therapeutic benefits including higher efficiencies and reduced adverse effects, the identification of such ligands as drug candidates is highly desirable. This review aims to provide an overview of the challenges and strategies in the discovery of biased ligands. We show different approaches for biased ligand discovery in the example of G-protein-biased opioid analgesics and discuss possibilities to design biased ligands by targeting extracellular receptor regions.

[144]

P. Durairaj, L. Fan, D. Machalz, G. Wolber, and M. Bureik. Functional characterization and mechanistic modeling of the human cytochrome P450 enzyme CYP4A22, Febs Lett, 593(16):2214-2225, 2019.
Links: [doi:10.1002/1873-3468.13489] [show BibTeX] [show abstract]  x  @article{RN275, author = {Durairaj, Pradeepraj and Fan, Linbing and Machalz, David and Wolber, Gerhard and Bureik, Matthias}, title = {Functional characterization and mechanistic modeling of the human cytochrome P450 enzyme CYP4A22}, journal = {FEBS Letters}, volume = {593}, number = {16}, pages = {2214-2225}, abstract = {The human cytochrome P450 (CYP) enzyme CYP4A22 is an orphan CYP with unknown function. Here, through functional expression in fission yeast, we show that CYP4A22 catalyzes fatty acid hydroxylation as well as aliphatic or aromatic hydroxylations of luciferin-based probe substrates. Mechanistic molecular modeling of CYP4A22 suggests that its ω-hydroxylation activity is hampered by a more spacious active site compared to CYP4B1. Substrate recognition via side-chains R96 and R233 is indicated by dynamic three-dimensional pharmacophores (dynophores) derived from molecular dynamics simulations. CYP4A22 activity is inhibited by three unspecific CYP inhibitors. A comparison of CYP4A22*1 (the reference standard sequence) with CYP4A22-WT (the most common allele) revealed that for the four substrates tested the WT-enzyme always had lower activity.}, ISSN = {0014-5793}, DOI = {10.1002/1873-3468.13489}, url = {https://febs.onlinelibrary.wiley.com/doi/abs/10.1002/1873-3468.13489 https://febs.onlinelibrary.wiley.com/doi/pdf/10.1002/1873-3468.13489}, year = {2019}, type = {Journal Article} }  x  Functional characterization and mechanistic modeling of the human cytochrome P450 enzyme CYP4A22

The human cytochrome P450 (CYP) enzyme CYP4A22 is an orphan CYP with unknown function. Here, through functional expression in fission yeast, we show that CYP4A22 catalyzes fatty acid hydroxylation as well as aliphatic or aromatic hydroxylations of luciferin-based probe substrates. Mechanistic molecular modeling of CYP4A22 suggests that its ω-hydroxylation activity is hampered by a more spacious active site compared to CYP4B1. Substrate recognition via side-chains R96 and R233 is indicated by dynamic three-dimensional pharmacophores (dynophores) derived from molecular dynamics simulations. CYP4A22 activity is inhibited by three unspecific CYP inhibitors. A comparison of CYP4A22*1 (the reference standard sequence) with CYP4A22-WT (the most common allele) revealed that for the four substrates tested the WT-enzyme always had lower activity.

[143]

A. Nass, D. Schaller, and G. Wolber. Assessment of flexible shape complementarity: New opportunities to explain and induce selectivity in ligands of protein tyrosine phosphatase 1B, Mol Inf, 38(5):1800141, 2019.
Links: [doi:10.1002/minf.201800141] [show BibTeX] [show abstract]  x  @article{RN268, author = {Nass, A. and Schaller, D. and Wolber, G.}, title = {Assessment of flexible shape complementarity: New opportunities to explain and induce selectivity in ligands of protein tyrosine phosphatase 1B}, journal = {Molecular Informatics}, volume = {38}, number = {5}, pages = {1800141}, note = {Nass, Alexandra Schaller, David Wolber, Gerhard eng Elsa-Neumann-Foundation Germany Mol Inform. 2019 Feb 6. doi: 10.1002/minf.201800141.}, abstract = {For drug design projects it is essential to rationally induce and explain selectivity. In this context shape complementarity as well as protein and ligand flexibility represent important factors. Currently available tools for the analysis of protein-ligand interactions focus mainly on electrostatic complementarity and/or static structures. Here we address the shortcomings of available methods by presenting two new tools: The first one can be used to assess steric complementarity in flexible protein-ligand complexes in order to explain selectivity of known ligands. It further allows to determine ligand atoms with especially good or bad shape-fit which can be of use in lead optimization projects. The second tool was designed to detect differences in protein flexibility in similar proteins along with their exploitation for virtual screening. Both tools yield interesting results when applied to data of protein tyrosine phosphatase 1B (PTP1B): The case of PTP1B has proven especially difficult in terms of selectivity, due to a closely related phosphatase connected to severe undesired effects. With our tool for steric complementarity assessment we were able to explain previously undisclosed causes of moderate selectivity of selected PTP1B ligands. The second tool allowed us to find differences of flexibility in the two highly similar proteins and give directions for exploitation in virtual screening.}, keywords = {Computational chemistry Molecular dynamics Molecular modeling Selectivity Shape complementarity}, ISSN = {1868-1751 (Electronic) 1868-1743 (Linking)}, DOI = {10.1002/minf.201800141}, url = {https://www.ncbi.nlm.nih.gov/pubmed/30725529 https://onlinelibrary.wiley.com/doi/pdf/10.1002/minf.201800141}, year = {2019}, type = {Journal Article} }  x  Assessment of flexible shape complementarity: New opportunities to explain and induce selectivity in ligands of protein tyrosine phosphatase 1B

For drug design projects it is essential to rationally induce and explain selectivity. In this context shape complementarity as well as protein and ligand flexibility represent important factors. Currently available tools for the analysis of protein-ligand interactions focus mainly on electrostatic complementarity and/or static structures. Here we address the shortcomings of available methods by presenting two new tools: The first one can be used to assess steric complementarity in flexible protein-ligand complexes in order to explain selectivity of known ligands. It further allows to determine ligand atoms with especially good or bad shape-fit which can be of use in lead optimization projects. The second tool was designed to detect differences in protein flexibility in similar proteins along with their exploitation for virtual screening. Both tools yield interesting results when applied to data of protein tyrosine phosphatase 1B (PTP1B): The case of PTP1B has proven especially difficult in terms of selectivity, due to a closely related phosphatase connected to severe undesired effects. With our tool for steric complementarity assessment we were able to explain previously undisclosed causes of moderate selectivity of selected PTP1B ligands. The second tool allowed us to find differences of flexibility in the two highly similar proteins and give directions for exploitation in virtual screening.

[142]

M. J. Ojeda-Montes, A. Casanova-Marti, A. Gimeno, S. Tomas-Hernandez, A. Cereto-Massague, G. Wolber, R. Beltran-Debon, C. Valls, M. Mulero, M. Pinent, G. Pujadas, and S. Garcia-Vallve. Mining large databases to find new leads with low similarity to known actives: application to find new DPP-IV inhibitors, Future Medicinal Chemistry, 11(12):1387-1401, 2019.
Links: [doi:10.4155/fmc-2018-0597] [show BibTeX] [show abstract]  x  @article{RN272, author = {Ojeda-Montes, M. J. and Casanova-Marti, A. and Gimeno, A. and Tomas-Hernandez, S. and Cereto-Massague, A. and Wolber, G. and Beltran-Debon, R. and Valls, C. and Mulero, M. and Pinent, M. and Pujadas, G. and Garcia-Vallve, S.}, title = {Mining large databases to find new leads with low similarity to known actives: application to find new DPP-IV inhibitors}, journal = {Future Medicinal Chemistry}, volume = {11}, number = {12}, pages = {1387-1401}, note = {Ojeda-Montes, Maria J Casanova-Marti, Angela Gimeno, Aleix Tomas-Hernandez, Sarah Cereto-Massague, Adria Wolber, Gerhard Beltran-Debon, Raul Valls, Cristina Mulero, Miquel Pinent, Montserrat Pujadas, Gerard Garcia-Vallve, Santiago eng England Future Med Chem. 2019 Jun;11(12):1387-1401. doi: 10.4155/fmc-2018-0597. Epub 2019 Jul 12.}, abstract = {Aim: Fragment-based drug design or bioisosteric replacement is used to find new actives with low (or no) similarity to existing ones but requires the synthesis of nonexisting compounds to prove their predicted bioactivity. Protein-ligand docking or pharmacophore screening are alternatives but they can become computationally expensive when applied to very large databases such as ZINC. Therefore, fast strategies are necessary to find new leads in such databases. Materials & methods: We designed a computational strategy to find lead molecules with very low (or no) similarity to existing actives and applied it to DPP-IV. Results: The bioactivity assays confirm that this strategy finds new leads for DPP-IV inhibitors. Conclusion: This computational strategy reduces the time of finding new lead molecules.}, keywords = {Cd26 dipeptidyl peptidase 4 diversifying molecular scaffolds expanding chemical space molecular fingerprints virtual molecular libraries virtual screening}, ISSN = {1756-8927 (Electronic) 1756-8919 (Linking)}, DOI = {10.4155/fmc-2018-0597}, url = {https://www.ncbi.nlm.nih.gov/pubmed/31298576}, year = {2019}, type = {Journal Article} }  x  Mining large databases to find new leads with low similarity to known actives: application to find new DPP-IV inhibitors

Aim: Fragment-based drug design or bioisosteric replacement is used to find new actives with low (or no) similarity to existing ones but requires the synthesis of nonexisting compounds to prove their predicted bioactivity. Protein-ligand docking or pharmacophore screening are alternatives but they can become computationally expensive when applied to very large databases such as ZINC. Therefore, fast strategies are necessary to find new leads in such databases. Materials & methods: We designed a computational strategy to find lead molecules with very low (or no) similarity to existing actives and applied it to DPP-IV. Results: The bioactivity assays confirm that this strategy finds new leads for DPP-IV inhibitors. Conclusion: This computational strategy reduces the time of finding new lead molecules.

[141]

R. Ottanà, P. Paoli, G. Lori, I. Adornato, S. Previti, A. Naß, G. Wolber, and R. Maccari. Design and evaluation of non-carboxylate 5-arylidene-2-thioxo-4-imidazolidinones as novel non-competitive inhibitors of protein tyrosine phosphatase 1B, Bioorg Chem, 92:103211, 2019.
Links: [doi:10.1016/j.bioorg.2019.103211] [show BibTeX] [show abstract]  x  @article{RN278, author = {Ottanà, Rosaria and Paoli, Paolo and Lori, Giulia and Adornato, Ilenia and Previti, Santo and Naß, Alexandra and Wolber, Gerhard and Maccari, Rosanna}, title = {Design and evaluation of non-carboxylate 5-arylidene-2-thioxo-4-imidazolidinones as novel non-competitive inhibitors of protein tyrosine phosphatase 1B}, journal = {Bioorganic Chemistry}, volume = {92}, pages = {103211}, abstract = {Protein tyrosine phosphatase 1B (PTP1B) acts as a negative regulator of insulin and leptin signalling and is crucially involved in the development of type 2 diabetes mellitus, obesity, cancer and neurodegenerative diseases. Pursuing our efforts to identify PTP1B inhibitors endowed with drug-like properties, we designed and evaluated 3-aryl-5-arylidene-2-thioxo-4-imidazolidinones (7) as a novel class of non-carboxylate PTP1B inhibitors. In agreement with our design, kinetic studies demonstrated that selected compounds 7 act as reversible, non-competitive inhibitors of the target enzyme at low micromolar concentrations. Accordingly, molecular docking experiments suggested that these inhibitors can fit an allosteric site of PTP1B that we previously individuated. Moreover, cellular assays demonstrated that compound 7e acts as a potent insulin-sensitizing agent in human liver HepG2 cells. Taken together, our results showed that these non-competitive PTP1B inhibitors can be considered promising lead compounds aimed to enhance druggability of the target enzyme and identify novel antidiabetic drugs.}, keywords = {3-aryl-5-arylidene-2-thioxo-4-imidazolidinones Protein tyrosine phosphatase 1B Non-competitive inhibitors Insulin-sensitizing agents Cellular assays}, ISSN = {00452068}, DOI = {10.1016/j.bioorg.2019.103211}, url = {http://www.sciencedirect.com/science/article/pii/S0045206819307990 https://www.sciencedirect.com/science/article/abs/pii/S0045206819307990?via%3Dihub}, year = {2019}, type = {Journal Article} }  x  Design and evaluation of non-carboxylate 5-arylidene-2-thioxo-4-imidazolidinones as novel non-competitive inhibitors of protein tyrosine phosphatase 1B

Protein tyrosine phosphatase 1B (PTP1B) acts as a negative regulator of insulin and leptin signalling and is crucially involved in the development of type 2 diabetes mellitus, obesity, cancer and neurodegenerative diseases. Pursuing our efforts to identify PTP1B inhibitors endowed with drug-like properties, we designed and evaluated 3-aryl-5-arylidene-2-thioxo-4-imidazolidinones (7) as a novel class of non-carboxylate PTP1B inhibitors. In agreement with our design, kinetic studies demonstrated that selected compounds 7 act as reversible, non-competitive inhibitors of the target enzyme at low micromolar concentrations. Accordingly, molecular docking experiments suggested that these inhibitors can fit an allosteric site of PTP1B that we previously individuated. Moreover, cellular assays demonstrated that compound 7e acts as a potent insulin-sensitizing agent in human liver HepG2 cells. Taken together, our results showed that these non-competitive PTP1B inhibitors can be considered promising lead compounds aimed to enhance druggability of the target enzyme and identify novel antidiabetic drugs.

[140]

D. Schaller, S. Hagenow, H. Stark, and G. Wolber. Ligand-guided homology modeling drives identification of novel histamine H3 receptor ligands, Plos One, 14(6):e0218820, 2019.
Links: [doi:10.1371/journal.pone.0218820] [show BibTeX] [show abstract]  x  @article{RN274, author = {Schaller, D. and Hagenow, S. and Stark, H. and Wolber, G.}, title = {Ligand-guided homology modeling drives identification of novel histamine H3 receptor ligands}, journal = {PLoS One}, volume = {14}, number = {6}, pages = {e0218820}, note = {Schaller, David Hagenow, Stefanie Stark, Holger Wolber, Gerhard eng PLoS One. 2019 Jun 25;14(6):e0218820. doi: 10.1371/journal.pone.0218820. eCollection 2019.}, abstract = {In this study, we report a ligand-guided homology modeling approach allowing the analysis of relevant binding site residue conformations and the identification of two novel histamine H3 receptor ligands with binding affinity in the nanomolar range. The newly developed method is based on exploiting an essential charge interaction characteristic for aminergic G-protein coupled receptors for ranking 3D receptor models appropriate for the discovery of novel compounds through virtual screening.}, ISSN = {1932-6203 (Electronic) 1932-6203 (Linking)}, DOI = {10.1371/journal.pone.0218820}, url = {https://www.ncbi.nlm.nih.gov/pubmed/31237914 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6592549/pdf/pone.0218820.pdf}, year = {2019}, type = {Journal Article} }  x  Ligand-guided homology modeling drives identification of novel histamine H3 receptor ligands

In this study, we report a ligand-guided homology modeling approach allowing the analysis of relevant binding site residue conformations and the identification of two novel histamine H3 receptor ligands with binding affinity in the nanomolar range. The newly developed method is based on exploiting an essential charge interaction characteristic for aminergic G-protein coupled receptors for ranking 3D receptor models appropriate for the discovery of novel compounds through virtual screening.

[139]

D. Schaller, S. Pach, and G. Wolber. PyRod: Tracing water molecules in molecular dynamics simulations, J Chem Inf Model, 59(6):2818-2829, 2019.
Links: [doi:10.1021/acs.jcim.9b00281] [show BibTeX] [show abstract]  x  @article{RN270, author = {Schaller, D. and Pach, S. and Wolber, G.}, title = {PyRod: Tracing water molecules in molecular dynamics simulations}, journal = {Journal of Chemical Information and Modeling}, volume = {59}, number = {6}, pages = {2818-2829}, note = {Schaller, David Pach, Szymon Wolber, Gerhard eng J Chem Inf Model. 2019 Jun 24;59(6):2818-2829. doi: 10.1021/acs.jcim.9b00281. Epub 2019 May 30.}, abstract = {Ligands entering a protein binding pocket essentially compete with water molecules for binding to the protein. Hence, the location and thermodynamic properties of water molecules in protein structures have gained increased attention in the drug design community. Including corresponding data into 3D pharmacophore modeling is essential for efficient high throughput virtual screening. Here, we present PyRod, a free and open-source Python software that allows for visualization of pharmacophoric binding pocket characteristics, identification of hot spots for ligand binding, and subsequent generation of pharmacophore features for virtual screening. The implemented routines analyze the protein environment of water molecules in molecular dynamics (MD) simulations and can differentiate between hydrogen bonded waters as well as waters in a protein environment of hydrophobic, charged, or aromatic atom groups. The gathered information is further processed to generate dynamic molecular interaction fields (dMIFs) for visualization and pharmacophoric features for virtual screening. The described software was applied to 5 therapeutically relevant drug targets, and generated pharmacophores were evaluated using DUD-E benchmarking sets. The best performing pharmacophore was found for the HIV1 protease with an early enrichment factor of 54.6. PyRod adds a new perspective to structure-based screening campaigns by providing easy-to-interpret dMIFs and purely protein-based pharmacophores that are solely based on tracing water molecules in MD simulations. Since structural information about cocrystallized ligands is not needed, screening campaigns can be followed, for which less or no ligand information is available. PyRod is freely available at https://github.com/schallerdavid/pyrod .}, keywords = {software}, ISSN = {1549-960X (Electronic) 1549-9596 (Linking)}, DOI = {10.1021/acs.jcim.9b00281}, url = {https://www.ncbi.nlm.nih.gov/pubmed/31117512}, year = {2019}, type = {Journal Article} }  x  PyRod: Tracing water molecules in molecular dynamics simulations

Ligands entering a protein binding pocket essentially compete with water molecules for binding to the protein. Hence, the location and thermodynamic properties of water molecules in protein structures have gained increased attention in the drug design community. Including corresponding data into 3D pharmacophore modeling is essential for efficient high throughput virtual screening. Here, we present PyRod, a free and open-source Python software that allows for visualization of pharmacophoric binding pocket characteristics, identification of hot spots for ligand binding, and subsequent generation of pharmacophore features for virtual screening. The implemented routines analyze the protein environment of water molecules in molecular dynamics (MD) simulations and can differentiate between hydrogen bonded waters as well as waters in a protein environment of hydrophobic, charged, or aromatic atom groups. The gathered information is further processed to generate dynamic molecular interaction fields (dMIFs) for visualization and pharmacophoric features for virtual screening. The described software was applied to 5 therapeutically relevant drug targets, and generated pharmacophores were evaluated using DUD-E benchmarking sets. The best performing pharmacophore was found for the HIV1 protease with an early enrichment factor of 54.6. PyRod adds a new perspective to structure-based screening campaigns by providing easy-to-interpret dMIFs and purely protein-based pharmacophores that are solely based on tracing water molecules in MD simulations. Since structural information about cocrystallized ligands is not needed, screening campaigns can be followed, for which less or no ligand information is available. PyRod is freely available at https://github.com/schallerdavid/pyrod .

[138]

S. Schramm, L. Agnetta, M. Bermudez, H. Gerwe, M. Irmen, J. Holze, T. Littmann, G. Wolber, C. Trankle, and M. Decker. Novel BQCA- and TBPB-derived M1 receptor hybrid ligands: Orthosteric carbachol differentially regulates partial agonism, ChemMedChem, 14(14):1349-1358, 2019.
Links: [doi:10.1002/cmdc.201900283] [show BibTeX] [show abstract]  x  @article{RN269, author = {Schramm, S. and Agnetta, L. and Bermudez, M. and Gerwe, H. and Irmen, M. and Holze, J. and Littmann, T. and Wolber, G. and Trankle, C. and Decker, M.}, title = {Novel BQCA- and TBPB-derived M1 receptor hybrid ligands: Orthosteric carbachol differentially regulates partial agonism}, journal = {ChemMedChem}, volume = {14}, number = {14}, pages = {1349-1358}, note = {Schramm, Simon Agnetta, Luca Bermudez, Marcel Gerwe, Hubert Irmen, Matthias Holze, Janine Littmann, Timo Wolber, Gerhard Trankle, Christian Decker, Michael eng International Doctoral program "Receptor Dynamics"/Elitenetzwerk Bayern Germany ChemMedChem. 2019 Jul 17;14(14):1349-1358. doi: 10.1002/cmdc.201900283. Epub 2019 Jul 3.}, abstract = {Recently, investigations of the complex mechanisms of allostery have led to a deeper understanding of G protein-coupled receptor (GPCR) activation and signaling processes. In this context, muscarinic acetylcholine receptors (mAChRs) are highly relevant due to their exemplary role in the study of allosteric modulation. In this work, we compare and discuss two sets of putatively dualsteric ligands, which were designed to connect carbachol to different types of allosteric ligands. We chose derivatives of TBPB [1-(1'-(2-tolyl)-1,4'-bipiperidin-4-yl)-1H-benzo[d]imidazol-2(3H)-one] as M1 -selective putative bitopic ligands, and derivatives of benzyl quinolone carboxylic acid (BQCA) as an M1 positive allosteric modulator, varying the distance between the allosteric and orthosteric building blocks. Luciferase protein complementation assays demonstrated that linker length must be carefully chosen to yield either agonist or antagonist behavior. These findings may help to design biased signaling and/or different extents of efficacy.}, keywords = {GPCRs allostery dualsteric ligands muscarinic receptors partial agonists}, ISSN = {1860-7187 (Electronic) 1860-7179 (Linking)}, DOI = {10.1002/cmdc.201900283}, url = {https://www.ncbi.nlm.nih.gov/pubmed/31166078 https://onlinelibrary.wiley.com/doi/pdf/10.1002/cmdc.201900283}, year = {2019}, type = {Journal Article} }  x  Novel BQCA- and TBPB-derived M1 receptor hybrid ligands: Orthosteric carbachol differentially regulates partial agonism

Recently, investigations of the complex mechanisms of allostery have led to a deeper understanding of G protein-coupled receptor (GPCR) activation and signaling processes. In this context, muscarinic acetylcholine receptors (mAChRs) are highly relevant due to their exemplary role in the study of allosteric modulation. In this work, we compare and discuss two sets of putatively dualsteric ligands, which were designed to connect carbachol to different types of allosteric ligands. We chose derivatives of TBPB [1-(1'-(2-tolyl)-1,4'-bipiperidin-4-yl)-1H-benzo[d]imidazol-2(3H)-one] as M1 -selective putative bitopic ligands, and derivatives of benzyl quinolone carboxylic acid (BQCA) as an M1 positive allosteric modulator, varying the distance between the allosteric and orthosteric building blocks. Luciferase protein complementation assays demonstrated that linker length must be carefully chosen to yield either agonist or antagonist behavior. These findings may help to design biased signaling and/or different extents of efficacy.

[137]

D. Sribar, M. Grabowski, M. S. Murgueitio, M. Bermudez, G. Weindl, and G. Wolber. Identification and characterization of a novel chemotype for human TLR8 inhibitors, Eur J Med Chem, 179:744-752, 2019.
Links: [doi:10.1016/j.ejmech.2019.06.084] [show BibTeX] [show abstract]  x  @article{RN273, author = {Sribar, D. and Grabowski, M. and Murgueitio, M. S. and Bermudez, M. and Weindl, G. and Wolber, G.}, title = {Identification and characterization of a novel chemotype for human TLR8 inhibitors}, journal = {European Journal of Medicinal Chemistry}, volume = {179}, pages = {744-752}, note = {Sribar, Dora Grabowski, Maria Murgueitio, Manuela S Bermudez, Marcel Weindl, Gunther Wolber, Gerhard eng France Eur J Med Chem. 2019 Jun 29;179:744-752. doi: 10.1016/j.ejmech.2019.06.084.}, abstract = {The endosomal Toll-like receptor 8 (TLR8) recognizes single-stranded RNA and initiates early inflammatory responses. Despite the importance of endosomal TLRs for human host defense against microbial pathogens, extensive activation may contribute to autoimmune and inflammatory diseases. In contrast to the recent progress made in the development of modulators of plasma membrane-bound TLRs, little is known about endosomal TLR modulation and very few TLR8 inhibitors have been reported. In this study, we discovered and validated novel small-molecule TLR8 inhibitors. Fourteen potential TLR8 modulators were experimentally validated in HEK293T cells stably overexpressing human TLR8 and THP-1 macrophages. Five compounds inhibited TLR8-mediated signaling, representing a hit rate of 36%. The three most potent compounds neither cause cellular toxicity nor inhibition of TLR signaling induced by other receptor subtypes. Conclusively, we experimentally confirm novel and selective, pyrimidine-based TLR8 inhibitors with low cytotoxicity that are relevant candidates for lead optimization and further mechanistic studies.}, keywords = {Inflammation Inhibitors Pyrimidine scaffold Toll-like receptor 8 Virtual screening}, ISSN = {1768-3254 (Electronic) 0223-5234 (Linking)}, DOI = {10.1016/j.ejmech.2019.06.084}, year = {2019}, type = {Journal Article} }  x  Identification and characterization of a novel chemotype for human TLR8 inhibitors

The endosomal Toll-like receptor 8 (TLR8) recognizes single-stranded RNA and initiates early inflammatory responses. Despite the importance of endosomal TLRs for human host defense against microbial pathogens, extensive activation may contribute to autoimmune and inflammatory diseases. In contrast to the recent progress made in the development of modulators of plasma membrane-bound TLRs, little is known about endosomal TLR modulation and very few TLR8 inhibitors have been reported. In this study, we discovered and validated novel small-molecule TLR8 inhibitors. Fourteen potential TLR8 modulators were experimentally validated in HEK293T cells stably overexpressing human TLR8 and THP-1 macrophages. Five compounds inhibited TLR8-mediated signaling, representing a hit rate of 36%. The three most potent compounds neither cause cellular toxicity nor inhibition of TLR signaling induced by other receptor subtypes. Conclusively, we experimentally confirm novel and selective, pyrimidine-based TLR8 inhibitors with low cytotoxicity that are relevant candidates for lead optimization and further mechanistic studies.

[136]

A. Stoll, S. Loke, J. F. Joseph, D. Machalz, X. de la Torre, F. Botrè, G. Wolber, M. Bureik, and M. K. Parr. Fine-mapping of the substrate specificity of human steroid 21-hydroxylase (CYP21A2), J Steroid Biochem, 194:105446, 2019.
Links: [doi:10.1016/j.jsbmb.2019.105446] [show BibTeX] [show abstract]  x  @article{RN277, author = {Stoll, Anna and Loke, Steffen and Joseph, Jan Felix and Machalz, David and de la Torre, Xavier and Botrè, Francesco and Wolber, Gerhard and Bureik, Matthias and Parr, Maria Kristina}, title = {Fine-mapping of the substrate specificity of human steroid 21-hydroxylase (CYP21A2)}, journal = {Journal of Steroid Biochemistry and Molecular Biology}, volume = {194}, pages = {105446}, abstract = {Cytochrome P450 enzymes (CYPs) are capable of catalyzing regio- and stereo-specific oxy functionalization reactions which otherwise are major challenges in organic chemistry. In order to make the best possible use of these biocatalysts it is imperative to understand their specificities. Human CYP21A2 (steroid 21-hydroxylase) acts on the side-chain attached to C-17 in ring D of a steroid substrate, but the configuration of ring A also plays a prominent role in substrate cognition. Here, we comprehensively investigated this relationship using sixteen 17,17-dimethyl-18-nor-13-ene steroids with different arrangements of hydroxy-, oxo-, fluoro- and chloro-groups and in the presence or absence of double bonds (Δ1 and/or Δ4) and heteroatoms in ring A. The results show that presence of a 3-oxo group is a strict requirement for a CYP21A2 substrate, while the other configurations tested were all tolerated. This was also confirmed by control experiments using endogenous steroids. While progesterone and 17-hydroxyprogesterone were hydroxylated at C-21, (17-hydroxy-) pregnenolone did not react. Molecular docking experiments indicate that the interaction of the carbonyl group at C-3 to the side-chain Arg234 of the enzyme is indispensable.}, keywords = {Cytochrome P450 Fission yeast Gas chromatography mass spectrometry (GCMS) Oral turinabol long-term metabolite Molecular modeling Steroid hydroxylation}, ISSN = {0960-0760}, DOI = {10.1016/j.jsbmb.2019.105446}, url = {http://www.sciencedirect.com/science/article/pii/S0960076019304169 https://pdf.sciencedirectassets.com/271264/1-s2.0-S0960076019X00096/1-s2.0-S0960076019304169/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJr%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIBmGoQIBcjjZ5EaOK3PJ%2FGurZx%2F3iAg7AxgzJBGlS1pLAiEAqq3PoXrNmhK0J8VvhGKQxD8CDm2MMxpACdgEvvCDCF0q2gMIQhACGgwwNTkwMDM1NDY4NjUiDB%2FjPXYQeqnKPMIAZSq3Axc0m%2BRD9Wt3prnTKye3Cqvo0AREbqzZ946GaterseGXxpe%2BUb3tyOJVBoXAsvayOEvYdT75FjY53skFYyeai6OYOXjZRWTEelsGyFCQf8cT3DEzx4Q%2FSuFEL5blDoqhss6bszDRC5%2FuVVpSzUmF7%2BFyAgGxxPdatNCbBmiutHGyRMn4PicJgX1DP70wJovm2MIIfOQjtVBAoW1FPcQfo4A0fJI5ShSReUYAnaXr04R8cTE%2BTTnwOVhgNPw19doX3%2FZOAC3wHvx2xdw427PkU7STXll%2FivSFUP2UPMpj5wiro1CxQicswmv0RAWfVQV%2BoN9oIuCE4eWm%2FoT86KudK0SbLCkH8hiO85Gkxien8zQf3J%2BA2aXelkRNwjG55dMxfLKxuLd5mhDnokYj7cOpwsS9sVe2WOpNw0L83GU%2FpuvVJI9vZFARLk225K%2FQ4b1pFcwGOKOAZBiAQZJ9D7JWTWR0gA8Y9KTN%2FrSCDcM7e3OCrDWcifFbCTor1FSCUFanT4fycawD7p8nphvKBxLQcZTmUo0CLG0aAL6hXvuI45m7qu0ijPUXIyCJTvyurXi9RPRuVGihaxkw98KO6wU6tAGChddaHRM2ELzStD4I3%2BltvO8qU5OvXkFpFPXsJT4YQCQafydsDiutI4rsZ8MyFKk2VmqAYvFy3yg9tm4P88k25cm8YxrYD9FZBt34b46IAXloCTW%2BjWdZAQpgxFCuBBURFwPqw%2Bz5EL4gHYjp%2BQW%2FHnmtR8SfofKETRV74Znvs9OncFyjtB09l8I8dyXKRPvZSo%2BtyGyKRjRStMbqfOcty%2BjSd%2FWSyeoJFlE6ZwZclpM4vEI%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090950Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYQ4T4FY7Z%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=e68521637f2f925edb79cb073fbe9fefc601f2c19dfc0856a00eef1bb77d9289&hash=48a45c8b2b325cd841876c27b55a565096a60658bea393cbcbd5a4ba39405d2d&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0960076019304169&tid=spdf-6023d6ec-532c-4043-9b99-f4f2eb5c3bdf&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2019}, type = {Journal Article} }  x  Fine-mapping of the substrate specificity of human steroid 21-hydroxylase (CYP21A2)

Cytochrome P450 enzymes (CYPs) are capable of catalyzing regio- and stereo-specific oxy functionalization reactions which otherwise are major challenges in organic chemistry. In order to make the best possible use of these biocatalysts it is imperative to understand their specificities. Human CYP21A2 (steroid 21-hydroxylase) acts on the side-chain attached to C-17 in ring D of a steroid substrate, but the configuration of ring A also plays a prominent role in substrate cognition. Here, we comprehensively investigated this relationship using sixteen 17,17-dimethyl-18-nor-13-ene steroids with different arrangements of hydroxy-, oxo-, fluoro- and chloro-groups and in the presence or absence of double bonds (Δ1 and/or Δ4) and heteroatoms in ring A. The results show that presence of a 3-oxo group is a strict requirement for a CYP21A2 substrate, while the other configurations tested were all tolerated. This was also confirmed by control experiments using endogenous steroids. While progesterone and 17-hydroxyprogesterone were hydroxylated at C-21, (17-hydroxy-) pregnenolone did not react. Molecular docking experiments indicate that the interaction of the carbonyl group at C-3 to the side-chain Arg234 of the enzyme is indispensable.

[135]

N. K. Wenke, J. Kreye, E. Andrzejak, A. van Casteren, J. Leubner, M. S. Murgueitio, S. M. Reincke, C. Secker, L. Schmidl, C. Geis, F. Ackermann, M. Nikolaus, C. C. Garner, H. Wardemann, G. Wolber, and H. Pruess. NMDA receptor dysfunction via unmutated human antibodies against the NR1 subunit, Ann Neurol, 85(5):771-776, 2019.
Links: [doi:10.1002/ana.25460] [show BibTeX] [show abstract]  x  @article{RN266, author = {Wenke, Nina Kerstin and Kreye, Jakob and Andrzejak, Ewa and van Casteren, Adriana and Leubner, Jonas and Murgueitio, Manuela S. and Reincke, S. Momsen and Secker, Christopher and Schmidl, Lars and Geis, Christian and Ackermann, Frauke and Nikolaus, Marc and Garner, Craig C. and Wardemann, Hedda and Wolber, Gerhard and Pruess, Harald}, title = {NMDA receptor dysfunction via unmutated human antibodies against the NR1 subunit}, journal = {Annals of neurology}, volume = {85}, number = {5}, pages = {771-776}, abstract = {Anti‐N‐methyl‐D‐aspartate‐receptor (NMDAR) encephalitis is the most common autoimmune encephalitis related to autoantibody‐mediated synaptic dysfunction. Cerebrospinal fluid‐derived human monoclonal NR1 autoantibodies showed low numbers of somatic hypermutations or were unmutated. These unexpected germline‐configured antibodies showed weaker binding to the NMDAR than matured antibodies from the same patient. In primary hippocampal neurons, germline NR1 autoantibodies strongly and specifically reduced total and synaptic NMDAR currents in a dose‐ and time‐dependent manner. The findings suggest that functional NMDAR antibodies are part of the human naïve B cell repertoire. Given their effects on synaptic function, they might contribute to a broad spectrum of neuropsychiatric symptoms.}, ISSN = {0364-5134}, DOI = {10.1002/ana.25460}, url = {http://europepmc.org/abstract/MED/30843274 https://doi.org/10.1002/ana.25460 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6593665/pdf/ANA-85-771.pdf}, year = {2019}, type = {Journal Article} }  x  NMDA receptor dysfunction via unmutated human antibodies against the NR1 subunit

Anti‐N‐methyl‐D‐aspartate‐receptor (NMDAR) encephalitis is the most common autoimmune encephalitis related to autoantibody‐mediated synaptic dysfunction. Cerebrospinal fluid‐derived human monoclonal NR1 autoantibodies showed low numbers of somatic hypermutations or were unmutated. These unexpected germline‐configured antibodies showed weaker binding to the NMDAR than matured antibodies from the same patient. In primary hippocampal neurons, germline NR1 autoantibodies strongly and specifically reduced total and synaptic NMDAR currents in a dose‐ and time‐dependent manner. The findings suggest that functional NMDAR antibodies are part of the human naïve B cell repertoire. Given their effects on synaptic function, they might contribute to a broad spectrum of neuropsychiatric symptoms.

[134]

O. Zierau, A. Kolodziejczyk, G. Vollmer, D. Machalz, G. Wolber, D. Thieme, and A. M. Keiler. Comparison of the three SARMs RAD-140, GLPG0492 and GSK-2881078 in two different in vitro bioassays, and in an in silico androgen receptor binding assay, J Steroid Biochem, 189:81-86, 2019.
Links: [doi:10.1016/j.jsbmb.2019.02.014] [show BibTeX] [show abstract]  x  @article{RN265, author = {Zierau, Oliver and Kolodziejczyk, Annika and Vollmer, Günter and Machalz, David and Wolber, Gerhard and Thieme, Detlef and Keiler, Annekathrin Martina}, title = {Comparison of the three SARMs RAD-140, GLPG0492 and GSK-2881078 in two different in vitro bioassays, and in an in silico androgen receptor binding assay}, journal = {Journal of Steroid Biochemistry and Molecular Biology}, volume = {189}, pages = {81-86}, abstract = {Selective androgen receptor modulators comprise compounds that bind as ligands to the androgen receptor and possess tissue-selective activities. Ideally, they show agonistic properties in anabolic target tissues, while inducing antagonistic or only weak agonistic effects in reproductive organs. Due to their myoanabolic effects, selective androgen receptor modulators are included in the list of prohibited substances and methods of the World Anti-Doping Agency. In the current investigation, the androgenic potential of RAD-140, GSK-2881078 and GLPG0492 was comparably investigated in two different in vitro bioassays. In the yeast androgen screen, the androgenic effects were lower than in the reporter gene assay in prostate carcinoma cells (e.g. for GSK-2881078, the EC50 values were 4.44 × 10−6M in the yeast screen and 3.99 × 10-9M in the prostate cells respectively). For future investigations, it is of importance whether the yeast androgen screen, which has been proven to detect androgenic compounds in urine, can detect an abuse of the selective androgen receptor modulators. Molecular modeling of the binding to the androgen receptor ligand binding domain suggests slight differences in the binding modes of RAD-140, GSK-2881078 and GLPG0492. In conclusion, androgenic activity of the three non-steroidal compounds in the two different in vitro test systems confirmed the results of the in silico modeling of the androgen receptor binding.}, keywords = {Selective androgen receptor modulators Yeast androgen screen PC3(AR)cells Molecular modeling}, ISSN = {0960-0760}, DOI = {10.1016/j.jsbmb.2019.02.014}, url = {http://www.sciencedirect.com/science/article/pii/S0960076018306885 https://pdf.sciencedirectassets.com/271264/1-s2.0-S0960076019X00047/1-s2.0-S0960076018306885/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJr%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIBmGoQIBcjjZ5EaOK3PJ%2FGurZx%2F3iAg7AxgzJBGlS1pLAiEAqq3PoXrNmhK0J8VvhGKQxD8CDm2MMxpACdgEvvCDCF0q2gMIQhACGgwwNTkwMDM1NDY4NjUiDB%2FjPXYQeqnKPMIAZSq3Axc0m%2BRD9Wt3prnTKye3Cqvo0AREbqzZ946GaterseGXxpe%2BUb3tyOJVBoXAsvayOEvYdT75FjY53skFYyeai6OYOXjZRWTEelsGyFCQf8cT3DEzx4Q%2FSuFEL5blDoqhss6bszDRC5%2FuVVpSzUmF7%2BFyAgGxxPdatNCbBmiutHGyRMn4PicJgX1DP70wJovm2MIIfOQjtVBAoW1FPcQfo4A0fJI5ShSReUYAnaXr04R8cTE%2BTTnwOVhgNPw19doX3%2FZOAC3wHvx2xdw427PkU7STXll%2FivSFUP2UPMpj5wiro1CxQicswmv0RAWfVQV%2BoN9oIuCE4eWm%2FoT86KudK0SbLCkH8hiO85Gkxien8zQf3J%2BA2aXelkRNwjG55dMxfLKxuLd5mhDnokYj7cOpwsS9sVe2WOpNw0L83GU%2FpuvVJI9vZFARLk225K%2FQ4b1pFcwGOKOAZBiAQZJ9D7JWTWR0gA8Y9KTN%2FrSCDcM7e3OCrDWcifFbCTor1FSCUFanT4fycawD7p8nphvKBxLQcZTmUo0CLG0aAL6hXvuI45m7qu0ijPUXIyCJTvyurXi9RPRuVGihaxkw98KO6wU6tAGChddaHRM2ELzStD4I3%2BltvO8qU5OvXkFpFPXsJT4YQCQafydsDiutI4rsZ8MyFKk2VmqAYvFy3yg9tm4P88k25cm8YxrYD9FZBt34b46IAXloCTW%2BjWdZAQpgxFCuBBURFwPqw%2Bz5EL4gHYjp%2BQW%2FHnmtR8SfofKETRV74Znvs9OncFyjtB09l8I8dyXKRPvZSo%2BtyGyKRjRStMbqfOcty%2BjSd%2FWSyeoJFlE6ZwZclpM4vEI%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090959Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYQ4T4FY7Z%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=eeebe89dc7b803edab1802d7f7937d0988afcf62b96a832e6f62ad813ee4b3c7&hash=80147c3643733f04f0be90d02fa9badc86eacb637119a9c2ccefcd8a0217a49c&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0960076018306885&tid=spdf-742e1312-8b0a-4fb1-a7fe-20eb2f8b370f&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2019}, type = {Journal Article} }  x  Comparison of the three SARMs RAD-140, GLPG0492 and GSK-2881078 in two different in vitro bioassays, and in an in silico androgen receptor binding assay

Selective androgen receptor modulators comprise compounds that bind as ligands to the androgen receptor and possess tissue-selective activities. Ideally, they show agonistic properties in anabolic target tissues, while inducing antagonistic or only weak agonistic effects in reproductive organs. Due to their myoanabolic effects, selective androgen receptor modulators are included in the list of prohibited substances and methods of the World Anti-Doping Agency. In the current investigation, the androgenic potential of RAD-140, GSK-2881078 and GLPG0492 was comparably investigated in two different in vitro bioassays. In the yeast androgen screen, the androgenic effects were lower than in the reporter gene assay in prostate carcinoma cells (e.g. for GSK-2881078, the EC50 values were 4.44 × 10−6M in the yeast screen and 3.99 × 10-9M in the prostate cells respectively). For future investigations, it is of importance whether the yeast androgen screen, which has been proven to detect androgenic compounds in urine, can detect an abuse of the selective androgen receptor modulators. Molecular modeling of the binding to the androgen receptor ligand binding domain suggests slight differences in the binding modes of RAD-140, GSK-2881078 and GLPG0492. In conclusion, androgenic activity of the three non-steroidal compounds in the two different in vitro test systems confirmed the results of the in silico modeling of the androgen receptor binding.

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2018 and earlier

[133]

M. Grabowski, M. S. Murgueitio, M. Bermudez, J. Rademann, G. Wolber, and G. Weindl. Identification of a pyrogallol derivative as a potent and selective human TLR2 antagonist by structure-based virtual screening, Biochem Pharmacol, 154:148-160, 2018.
Links: [doi:10.1016/j.bcp.2018.04.018] [show BibTeX] [show abstract]  x  @article{RN260, author = {Grabowski, Maria and Murgueitio, Manuela S. and Bermudez, Marcel and Rademann, Jörg and Wolber, Gerhard and Weindl, Günther}, title = {Identification of a pyrogallol derivative as a potent and selective human TLR2 antagonist by structure-based virtual screening}, journal = {Biochemical Pharmacology}, volume = {154}, pages = {148-160}, abstract = {Toll-like receptor 2 (TLR2) induces early inflammatory responses to pathogen and damage-associated molecular patterns trough heterodimerization with either TLR1 or TLR6. Since overstimulation of TLR2 signaling is linked to several inflammatory and metabolic diseases, TLR2 antagonists may provide therapeutic benefits for the control of inflammatory conditions. We present virtual screening for the identification of novel TLR2 modulators, which combines analyses of known ligand sets with structure-based approaches. The 13 identified compounds were pharmacologically characterized in HEK293-hTLR2 cells, THP-1 macrophages and peripheral blood mononuclear cells for their ability to inhibit TLR2-mediated responses. Four out of 13 selected compounds show concentration-dependent activity, representing a hit rate of 31%. The most active compound is the pyrogallol derivative MMG-11 that inhibits both TLR2/1 and TLR2/6 signaling and shows a higher potency than the previously discovered CU-CPT22. Concentration ratio analysis identified both compounds as competitive antagonists of Pam3CSK4- and Pam2CSK4-induced responses. Schild plot analysis yielded apparent pA2 values of 5.73 and 6.15 (TLR2/1), and 5.80 and 6.65 (TLR2/6) for CU-CPT22 and MMG-11, respectively. MMG-11 neither shows cellular toxicity nor interference with signaling induced by other TLR agonists, IL-1β or TNF. Taken together, we demonstrate that MMG-11 is a potent and selective TLR2 antagonist with low cytotoxicity rendering it a promising pharmacological tool for the investigation of TLR signaling and a suitable lead structure for further chemical optimization.}, keywords = {Drug discovery Toll-like receptors TLR2 Virtual screening Competitive antagonist tlr}, ISSN = {0006-2952}, DOI = {10.1016/j.bcp.2018.04.018}, year = {2018}, type = {Journal Article} }  x  Identification of a pyrogallol derivative as a potent and selective human TLR2 antagonist by structure-based virtual screening

Toll-like receptor 2 (TLR2) induces early inflammatory responses to pathogen and damage-associated molecular patterns trough heterodimerization with either TLR1 or TLR6. Since overstimulation of TLR2 signaling is linked to several inflammatory and metabolic diseases, TLR2 antagonists may provide therapeutic benefits for the control of inflammatory conditions. We present virtual screening for the identification of novel TLR2 modulators, which combines analyses of known ligand sets with structure-based approaches. The 13 identified compounds were pharmacologically characterized in HEK293-hTLR2 cells, THP-1 macrophages and peripheral blood mononuclear cells for their ability to inhibit TLR2-mediated responses. Four out of 13 selected compounds show concentration-dependent activity, representing a hit rate of 31%. The most active compound is the pyrogallol derivative MMG-11 that inhibits both TLR2/1 and TLR2/6 signaling and shows a higher potency than the previously discovered CU-CPT22. Concentration ratio analysis identified both compounds as competitive antagonists of Pam3CSK4- and Pam2CSK4-induced responses. Schild plot analysis yielded apparent pA2 values of 5.73 and 6.15 (TLR2/1), and 5.80 and 6.65 (TLR2/6) for CU-CPT22 and MMG-11, respectively. MMG-11 neither shows cellular toxicity nor interference with signaling induced by other TLR agonists, IL-1β or TNF. Taken together, we demonstrate that MMG-11 is a potent and selective TLR2 antagonist with low cytotoxicity rendering it a promising pharmacological tool for the investigation of TLR signaling and a suitable lead structure for further chemical optimization.

[132]

A. M. Keiler, O. Zierau, S. Wolf, P. Diel, W. Schänzer, G. Vollmer, D. Machalz, G. Wolber, and M. K. Parr. Androgen- and estrogen-receptor mediated activities of 4-hydroxytestosterone, 4-hydroxyandrostenedione and their human metabolites in yeast based assays, Toxicol Lett, 292:39-45, 2018.
Links: [doi:10.1016/j.toxlet.2018.04.026] [show BibTeX] [show abstract]  x  @article{RN256, author = {Keiler, Annekathrin Martina and Zierau, Oliver and Wolf, Sylvi and Diel, Patrick and Schänzer, Wilhelm and Vollmer, Günter and Machalz, David and Wolber, Gerhard and Parr, Maria Kristina}, title = {Androgen- and estrogen-receptor mediated activities of 4-hydroxytestosterone, 4-hydroxyandrostenedione and their human metabolites in yeast based assays}, journal = {Toxicology Letters}, volume = {292}, pages = {39-45}, abstract = {4-Hydroxyandrost-4-ene-3,17-dione, also named formestane, is an irreversible aromatase inhibitor and therapeutically used as anti-breast cancer medication in post-menopausal women. Currently, no therapeutical indication led to approval of its 17-hydroxylated analog 4-hydroxytestosterone, an anabolic steroid. However, it is currently investigated in a clinical trial for breast cancer. In context with sports doping, aromatase inhibitors are administered to reduce estrogenic side effects of misused anabolic substances or their metabolites. Therefore, both substances are prohibited in sports by the World Anti-Doping Agency (WADA). Analysis of urinary phase I and phase II metabolites showed similar results for both compounds. In the current investigation, 4-hydroxyandrost-4-ene-3,17-dione, 4-hydroxytestosterone and seven of their described urinary metabolites as well as 2α-hydroxyandrostenedione were tested in the yeast androgen screen and the yeast estrogen screen. Androgenic effects were observed for all tested substances, except for one, which showed anti-androgenic properties. With regard to the yeast estrogen screen, estrogenic effects were observed for only two metabolites at rather high concentrations, while six out of the ten substances tested showed anti-estrogenic properties. In terms of the strong androgenic effect observed for 4-hydroxytestosterone (10−8 M), 4-hydroxyandrost-4-ene-3,17-dione (10−8 M) and two more urinary metabolites, the yeast androgen assay may also be used to trace abuse in urine samples.}, keywords = {Formestane 4-Hydroxytestosterone Doping Molecular modeling}, ISSN = {0378-4274}, DOI = {10.1016/j.toxlet.2018.04.026}, url = {http://www.sciencedirect.com/science/article/pii/S0378427418301644 https://www.sciencedirect.com/science/article/pii/S0378427418301644?via%3Dihub}, year = {2018}, type = {Journal Article} }  x  Androgen- and estrogen-receptor mediated activities of 4-hydroxytestosterone, 4-hydroxyandrostenedione and their human metabolites in yeast based assays

4-Hydroxyandrost-4-ene-3,17-dione, also named formestane, is an irreversible aromatase inhibitor and therapeutically used as anti-breast cancer medication in post-menopausal women. Currently, no therapeutical indication led to approval of its 17-hydroxylated analog 4-hydroxytestosterone, an anabolic steroid. However, it is currently investigated in a clinical trial for breast cancer. In context with sports doping, aromatase inhibitors are administered to reduce estrogenic side effects of misused anabolic substances or their metabolites. Therefore, both substances are prohibited in sports by the World Anti-Doping Agency (WADA). Analysis of urinary phase I and phase II metabolites showed similar results for both compounds. In the current investigation, 4-hydroxyandrost-4-ene-3,17-dione, 4-hydroxytestosterone and seven of their described urinary metabolites as well as 2α-hydroxyandrostenedione were tested in the yeast androgen screen and the yeast estrogen screen. Androgenic effects were observed for all tested substances, except for one, which showed anti-androgenic properties. With regard to the yeast estrogen screen, estrogenic effects were observed for only two metabolites at rather high concentrations, while six out of the ten substances tested showed anti-estrogenic properties. In terms of the strong androgenic effect observed for 4-hydroxytestosterone (10−8 M), 4-hydroxyandrost-4-ene-3,17-dione (10−8 M) and two more urinary metabolites, the yeast androgen assay may also be used to trace abuse in urine samples.

[131]

J. Liu, L. Chen, J. F. Joseph, A. Naß, A. Stoll, X. de la Torre, F. Botrè, G. Wolber, M. K. Parr, and M. Bureik. Combined chemical and biotechnological production of 20βOH-NorDHCMT, a long-term metabolite of Oral-Turinabol (DHCMT), J Inorg Biochem, 183:165-171, 2018.
Links: [doi:10.1016/j.jinorgbio.2018.02.020] [show BibTeX] [show abstract]  x  @article{RN257, author = {Liu, Jiaxin and Chen, Lei and Joseph, Jan Felix and Naß, Alexandra and Stoll, Anna and de la Torre, Xavier and Botrè, Francesco and Wolber, Gerhard and Parr, Maria Kristina and Bureik, Matthias}, title = {Combined chemical and biotechnological production of 20βOH-NorDHCMT, a long-term metabolite of Oral-Turinabol (DHCMT)}, journal = {Journal of Inorganic Biochemistry}, volume = {183}, pages = {165-171}, abstract = {Anabolic androgenic steroids (AAS) are misused very frequently in sport competitions as performance enhancing agents. One of the doping compounds that has been detected with increased frequency in the last few years is dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy-17α-methylandrosta-1,4-dien-3-one; brand name Oral Turinabol). The long-term DHCMT metabolite 20βOH-NorDHCMT (4-chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-1,4,13-trien-3-one) was reported earlier to be detectable in urine samples for more than 22 days after DHCMT administration; however, purified reference material was not available so far. In this study we demonstrate a successful combination of Wagner-Meerwein rearrangement of DHCMT to NorDHCMT (4-chloro-17,17-dimethyl-18-norandrosta-1,4,13-trien-3-one) and subsequent whole-cell biotransformation with a recombinant fission yeast strain expressing the human cytochrome P450 enzyme (CYP or P450) CYP21A2 for the synthesis of mg amounts of this metabolite. It was then used as reference for the analysis of a post administration urine of DHCMT. The availability of this reference compound will provide an incontestable proof for DHCMT abuse.}, keywords = {Anabolic androgenic steroids Doping Fission yeast Whole-cell biotransformation}, ISSN = {0162-0134}, DOI = {10.1016/j.jinorgbio.2018.02.020}, url = {http://www.sciencedirect.com/science/article/pii/S0162013417308516 https://pdf.sciencedirectassets.com/271941/1-s2.0-S0162013418X0004X/1-s2.0-S0162013417308516/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIBSuXR284U5c9bmAJSN5zVw47n5M5VTNwrBmGQ8hLXVcAiAWIgoCDAYq%2BrLMnoeOj0gcwMsJ%2BK2%2F2vx37jlwfG9V%2FiraAwhBEAIaDDA1OTAwMzU0Njg2NSIMjEBFMn9jIE9t1XN2KrcDLe7GRG%2FXcw3WEgKV9YXbSGYcHYB2z7r%2B9eRerOT0zpE0wRSFgQ%2FOH9BXlp37MIlzoDaMcVajFKZS8gcJXSICZZRdMHztkVCBW4DNZa%2BJxOwJ1E6Q6vzyyBGsc%2FRoV6Xba79A94ndoN8bYy6WNuplWyrl3mWsK2vv7sI6kqAQYvwZAuSo66P%2FLefOdgACsLXUvDUtMMpSN8TmoE6MAFh%2Fj9u1tN2PHd7Si9U0lR%2BPybWjyQIZhRLaPFiPA459dq%2F0DJYDW6PUXjnBlCqj2pjkDd8G%2FcrPGVCvjIs1dEukqNYRPh9wSQFFAb5Fi0wZV3zG%2F46Hc%2FeUQIprBOrsYtxFvQ1UWxSkaVfuuRD2NfJJC%2FoyWTyuxNmD0bdhukh9A21%2B1W83wJfu%2FecDVcxhN9MqXTDLroqrvl%2BRxWFnb%2BWbs%2B%2FV9bgL2cBI6AFt4X60UAEM%2FPSuYh%2FCMbaK1dtKiQLD4N%2F7kxQrpF%2BWzb6z4YOF5hW%2F4Jm%2BgH%2B0v9v9lego%2FcMGf98VdcRdShnMV0057mzmxPdKDL4AivAyKRRfnHrHbLoO1SdPlc41DKXR%2BjK0GtocjZ5j4aUAxDDnpo7rBTq1AThXMgqWLXhCysjiDb69KUDsmtirRuTrXpezLGPDfxkFp5ofIqWUR9J0yQNBLS%2BqlghqmfiGup4DJm90ED%2Bjr269Tuc2Ri4J0zfr7%2BcI1xixL%2Fy0rAQI30TJNbf1CsDGxfVixVDBG1Fkwa3KlpjjfAGAuGKaiPkPOMJuLo8YTbs28PVbbZSstkpcNX0npq661wJ6SM3c0BNDLzt2HCCzsKCoWT8MzDtnFnmY8Er2Z7ayg87lxx0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090907Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYZNRZYJFV%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=b720f3d2263dac5174d9f180a9eb5e614b3e41a49d79c0654e5cf2db83daf8ac&hash=b75427625e4bad8f5793e591fc5f3d24775b20f57d1f3e4528dd1440c335f22e&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0162013417308516&tid=spdf-730e9d0a-0d56-4e6a-a6a4-f7f6e8e867cf&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2018}, type = {Journal Article} }  x  Combined chemical and biotechnological production of 20βOH-NorDHCMT, a long-term metabolite of Oral-Turinabol (DHCMT)

Anabolic androgenic steroids (AAS) are misused very frequently in sport competitions as performance enhancing agents. One of the doping compounds that has been detected with increased frequency in the last few years is dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy-17α-methylandrosta-1,4-dien-3-one; brand name Oral Turinabol). The long-term DHCMT metabolite 20βOH-NorDHCMT (4-chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-1,4,13-trien-3-one) was reported earlier to be detectable in urine samples for more than 22 days after DHCMT administration; however, purified reference material was not available so far. In this study we demonstrate a successful combination of Wagner-Meerwein rearrangement of DHCMT to NorDHCMT (4-chloro-17,17-dimethyl-18-norandrosta-1,4,13-trien-3-one) and subsequent whole-cell biotransformation with a recombinant fission yeast strain expressing the human cytochrome P450 enzyme (CYP or P450) CYP21A2 for the synthesis of mg amounts of this metabolite. It was then used as reference for the analysis of a post administration urine of DHCMT. The availability of this reference compound will provide an incontestable proof for DHCMT abuse.

[130]

R. Maccari, A. Del Corso, P. Paoli, I. Adornato, G. Lori, F. Balestri, M. Cappiello, A. Naß, G. Wolber, and R. Ottana. An investigation on 4-thiazolidinone derivatives as dual inhibitors of aldose reductase and protein tyrosine phosphatase 1B, in the search for potential agents for the treatment of type 2 diabetes mellitus and its complications, Bioorg Med Chem Lett, 28(23-24):3712-3720, 2018.
Links: [doi:10.1016/j.bmcl.2018.10.024] [show BibTeX] [show abstract]  x  @article{RN261, author = {Maccari, Rosanna and Del Corso, Antonella and Paoli, Paolo and Adornato, Ilenia and Lori, Giulia and Balestri, Francesco and Cappiello, Mario and Naß, Alexandra and Wolber, Gerhard and Ottana, Rosaria}, title = {An investigation on 4-thiazolidinone derivatives as dual inhibitors of aldose reductase and protein tyrosine phosphatase 1B, in the search for potential agents for the treatment of type 2 diabetes mellitus and its complications}, journal = {Bioorganic & Medicinal Chemistry Letters}, volume = {28}, number = {23-24}, pages = {3712-3720}, note = {Maccari, Rosanna Del Corso, Antonella Paoli, Paolo Adornato, Ilenia Lori, Giulia Balestri, Francesco Cappiello, Mario Nass, Alexandra Wolber, Gerhard Ottana, Rosaria eng Research Support, Non-U.S. Gov't England Bioorg Med Chem Lett. 2018 Dec 15;28(23-24):3712-3720. doi: 10.1016/j.bmcl.2018.10.024. Epub 2018 Oct 15.}, abstract = {Designed multiple ligands (DMLs), developed to modulate simultaneously a number of selected targets involved in etiopathogenetic mechanisms of a multifactorial disease, such as diabetes mellitus (DM), are considered a promising alternative to combinations of drugs, when monotherapy results to be unsatisfactory. In this work, compounds 1–17 were synthesized and in vitro evaluated as DMLs directed to aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two key enzymes involved in different events which are critical for the onset and progression of type 2 DM and related pathologies. Out of the tested 4-thiazolidinone derivatives, compounds 12 and 16, which exhibited potent AR inhibitory effects along with interesting inhibition of PTP1B, can be assumed as lead compounds to further optimize and balance the dual inhibitory profile. Moreover, several structural portions were identified as features that could be useful to achieve simultaneous inhibition of both human AR and PTP1B through binding to non-catalytic regions of both target enzymes.}, keywords = {Diabetes mellitus Designed multiple ligands 4-Thiazolidinone derivatives Aldose reductase Protein tyrosine phosphatase 1B}, ISSN = {0960-894X}, DOI = {10.1016/j.bmcl.2018.10.024}, url = {http://www.sciencedirect.com/science/article/pii/S0960894X18308254 https://pdf.sciencedirectassets.com/271398/1-s2.0-S0960894X18X00225/1-s2.0-S0960894X18308254/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIBfvzJJhZ1Mm5mwy0J3B5VMuELdFjoz7sIRqN8wYSzx3AiEA5SeL7MgEjFO0B9r5FrlpUN4T0hArwMRoS5vGU9JFDzkq2gMIQhACGgwwNTkwMDM1NDY4NjUiDBOT17U1MUqycs1%2FKCq3AxGHFD6W1QLBSzH%2FhBU3v8JJteKuM%2BMlhBDgx9HJr06UFb8BZd%2BHmmbs1ur5t%2FlqtRCT5APQ%2Fzl6M%2FIM8%2F6YwmMYXt9Jyw268%2FtZeBsyIAjhb9UY49j0c7v6aVzNad%2FGYTpVso5RHp%2FRIuM5L67h7pTwnakyTSI6BnpaJqI2B9kWP4JEsZprxWxTmvQw9wKd%2BZ%2Fa4mZjyJSBse7DFly8%2FGnCKXIXFbkL7gEHIAamV19AyDb7zMu0NjKSYkVhnMKdyKtcoydss0kNGXNm7HiEVwqeBYZLCKy4Gr96z9kBNqkcZ%2BCvqAOmMj10aPUlpkLbmx197FcTVJ8VImn9RLlCJRDmDXNX5yS0%2B73PI%2BEazQ5%2BwF1N29hqIzLnT1Cc5utmeZ0G5AMefCBRfmgg6E2TbmfR7Ww0V5jCzNNuAslQXXlpfPN3WJ9keKLw21X%2BSCqBPm%2Fu6Xis2DUor4OC8wohPM2ZjGByx3Gqx2LFJIPCZN3cJyL1gxaivo%2BET3s3jVm6OY0z8nVa20tLJ7Fw2PK6UzrCG3VQ%2F1Wx6deq5BIg0CjfaQgBifcwYqv%2F%2F9ZMxV6ugcNNvcoHxYgw6rmO6wU6tAGkBGWe9a6585563qyrPRyFqAu%2FM2418LDCloFTRDRH9weZ%2BgHQW1B1m%2F%2FVbRWsTdBwvnU%2BOX7Dk7jsNsnZIzAffqBskxE32pvB9%2BEG%2Fi%2F0HR72BRBiQS0zSE42%2F3v4dfwbryhRJ%2FbSj6%2BtUzOYJwiXE%2BTFI6%2Bw6by7InD6OwR0E1IdegTjGtbvA15LPpug9CTJY%2FTVHEISFL2jcir2FrGkZbfPHhgSZLoAg3rn1UL%2Buq%2FcLM4%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090911Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYRDRFHOHF%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=feaf53b1f39ea803adab835418ba489cae4c6b949016e91c0fc74405f2220c83&hash=ec623c4bd4a7063e8d68152bb19a69be7b6f0203d7e5e52fe53b81ddea1e14ee&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0960894X18308254&tid=spdf-441f1cff-7ad6-4594-91a9-39f8bcc7b983&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2018}, type = {Journal Article} }  x  An investigation on 4-thiazolidinone derivatives as dual inhibitors of aldose reductase and protein tyrosine phosphatase 1B, in the search for potential agents for the treatment of type 2 diabetes mellitus and its complications

Designed multiple ligands (DMLs), developed to modulate simultaneously a number of selected targets involved in etiopathogenetic mechanisms of a multifactorial disease, such as diabetes mellitus (DM), are considered a promising alternative to combinations of drugs, when monotherapy results to be unsatisfactory. In this work, compounds 1–17 were synthesized and in vitro evaluated as DMLs directed to aldose reductase (AR) and protein tyrosine phosphatase 1B (PTP1B), two key enzymes involved in different events which are critical for the onset and progression of type 2 DM and related pathologies. Out of the tested 4-thiazolidinone derivatives, compounds 12 and 16, which exhibited potent AR inhibitory effects along with interesting inhibition of PTP1B, can be assumed as lead compounds to further optimize and balance the dual inhibitory profile. Moreover, several structural portions were identified as features that could be useful to achieve simultaneous inhibition of both human AR and PTP1B through binding to non-catalytic regions of both target enzymes.

[129]

R. Maccari, R. Ettari, I. Adornato, A. Naß, G. Wolber, A. Bitto, F. Mannino, F. Aliquo, G. Bruno, F. Nicolo, S. Previti, S. Grasso, M. Zappala, and R. Ottana. Identification of 2-thioxoimidazolidin-4-one derivatives as novel noncovalent proteasome and immunoproteasome inhibitors, Bioorg Med Chem Lett, 28(3):278-283, 2018.
Links: [doi:10.1016/j.bmcl.2017.12.053] [show BibTeX] [show abstract]  x  @article{RN251, author = {Maccari, Rosanna and Ettari, Roberta and Adornato, Ilenia and Naß, Alexandra and Wolber, Gerhard and Bitto, Alessandra and Mannino, Federica and Aliquo, Federica and Bruno, Giuseppe and Nicolo, Francesco and Previti, Santo and Grasso, Silvana and Zappala, Maria and Ottana, Rosaria}, title = {Identification of 2-thioxoimidazolidin-4-one derivatives as novel noncovalent proteasome and immunoproteasome inhibitors}, journal = {Bioorganic & Medicinal Chemistry Letters}, volume = {28}, number = {3}, pages = {278-283}, abstract = {This paper describes the design, synthesis, and biological evaluation of 2-thioxoimidazolidin-4-one derivatives as inhibitors of proteasome and immunoproteasome, potential targets for the treatment of hematological malignancies. In particular, we focused our efforts on the design of noncovalent inhibitors, which might be a promising therapeutic option potentially devoid of drawbacks and side-effects related to irreversible inhibition. Among all the synthesized compounds, we identified a panel of active inhibitors with Ki values towards one or two chymotrypsin-like activities of proteasome (β5c) and immunoproteasome (β5i and β1i subunits) in the low micromolar range. Docking studies suggested a unique binding mode of the molecules in the catalytic site of immunoproteasome proteolytic subunits.}, keywords = {Proteasome Immunoproteasome 5-Arylidene-2-thioxoimidazolidin-4-ones Non-covalent inhibitors Docking studies}, ISSN = {0960-894X}, DOI = {10.1016/j.bmcl.2017.12.053}, url = {http://www.sciencedirect.com/science/article/pii/S0960894X17312271 https://www.sciencedirect.com/science/article/pii/S0960894X17312271?via%3Dihub https://pdf.sciencedirectassets.com/271398/1-s2.0-S0960894X18X0002X/1-s2.0-S0960894X17312271/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIQDpMFAxqO8i5cWwO8J2bidQOOPWWOgX2xYgjlCqnmYpKAIgMz6zEqJOOqjcysWG%2F%2BjDZIPEG4hPysl42TQ%2BxrkJgLgq2gMIQRACGgwwNTkwMDM1NDY4NjUiDMbVMeQJp%2BA6xuTeeiq3A5yGUmiSxbecX6zyK9C0u9d8FvveGrkPLG2bgf%2FLpoQrYo2WyvA%2BBWqUubZ%2F%2F2lzFcSTpeDFbT3qjC0N3gXJAnlrhfnB4HtdM5JkFOs7rk4T5uxWa2QB%2Bxrb0uGWp6C%2FKniuq6eBMiJ59EW8Qua9SC1HjapOsfuus9g5HoQTBdya%2B%2B93vPUyT1l6n3DvNF79aTePLdf4GzCoc3La3CqQwXZ%2Bv00XVVkSLXyHqEtn%2BKj4RqGYDx5vybmCYgNtuQnt%2F4u%2FKij1yfRzcl%2BKOheRiB2UBQBFkx%2BGRL%2BqBFLx23kYZU2PrVD4ZjQMMXyglfn7R41W1Ts944jcTs7eKtPEaIuwbGZFi3rfxU%2BBL%2BrhXsqDJMbPTE%2BrqYpk6xiwMVJaY6kJH62kCLazVZrQ49cjhJjxeJti4aqVRxjr4XOP%2FJ9EatP%2BZoD3q47yNzrS1dG3FcQOp6Rtx1LGD9QPU8GrLpoB2%2F%2BrydWuCVqCFWw5iNbyp05sWQsfmSpFEMzsvkKO%2FCw0bATpkHdkF6WOn0A1lXIOsI0cDUPAe1xWJ3L0KZySQ0UZUqXJ8Gw4v%2FTlL5BY%2FUxSnor26xYwn6aO6wU6tAHBqopuW5pcz%2FJI%2BrCyUdYGVL8ZGUcN9osxZNHlsdHl%2FPSb5Ey3HqdiHTks1pszrFK8F0ZxsQNCYajkgKT3SAzhgrTmaNYfXyzLVkl3rMbW5QA0SqgsnR79JfHgUXuHGBnWyrsVF5mu9vmFjpTB4j2VqmtMOIjghMdHO%2FOIcR59ey2VTJQKE1Ulq0WJqECO72nl8nHMFEUoBLcWlCu5cwJlo5NxAcL7qC1hNPBzJlNFYMqU07s%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090916Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY5J43SP76%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=e7c2580b1bb9072e94b21c17a17e77638c77cc9426365c1d5789e72f4ef95b81&hash=61d4515aaf52ead90206956d3b9b1b4f62c4062ab11c5f1b52d8f8dd8b4e4eb5&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0960894X17312271&tid=spdf-2602928c-1628-4f42-ac59-ecd3a11225cf&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2018}, type = {Journal Article} }  x  Identification of 2-thioxoimidazolidin-4-one derivatives as novel noncovalent proteasome and immunoproteasome inhibitors

This paper describes the design, synthesis, and biological evaluation of 2-thioxoimidazolidin-4-one derivatives as inhibitors of proteasome and immunoproteasome, potential targets for the treatment of hematological malignancies. In particular, we focused our efforts on the design of noncovalent inhibitors, which might be a promising therapeutic option potentially devoid of drawbacks and side-effects related to irreversible inhibition. Among all the synthesized compounds, we identified a panel of active inhibitors with Ki values towards one or two chymotrypsin-like activities of proteasome (β5c) and immunoproteasome (β5i and β1i subunits) in the low micromolar range. Docking studies suggested a unique binding mode of the molecules in the catalytic site of immunoproteasome proteolytic subunits.

[128]

D. Schaller, M. G. Gündüz, F. X. Zhang, G. W. Zamponi, and G. Wolber. Binding mechanism investigations guiding the synthesis of novel condensed 1,4-dihydropyridine derivatives with L-/T-type calcium channel blocking activity, Eur J Med Chem, 155:1-12, 2018.
Links: [doi:10.1016/j.ejmech.2018.05.032] [show BibTeX] [show abstract]  x  @article{RN258, author = {Schaller, David and Gündüz, Miyase Gözde and Zhang, Fang Xiong and Zamponi, Gerald W. and Wolber, Gerhard}, title = {Binding mechanism investigations guiding the synthesis of novel condensed 1,4-dihydropyridine derivatives with L-/T-type calcium channel blocking activity}, journal = {European Journal of Medicinal Chemistry}, volume = {155}, pages = {1-12}, abstract = {Nifedipine and isradipine are prominent examples of calcium channel blockers with a 1,4-dihydropyridine (DHP) scaffold. Although successfully used in clinics since decades for the treatment of hypertension, the binding mechanism to their target, the L-type voltage-gated calcium channel Cav1.2, is still incompletely understood. Recently, novel DHP derivatives with a condensed ring system have been discovered that show distinct selectivity profiles to different calcium channel subtypes. This property renders this DHP class as a promising tool to achieve selectivity towards distinct calcium channel subtypes. In this study, we identified a common binding mode for prominent DHPs nifedipine and isradipine using docking and pharmacophore analysis that is also able to explain the structure-activity relationship of a small subseries of DHP derivatives with a condensed ring system. These findings were used to guide the synthesis of twenty-two novel DHPs. An extensive characterization using 1H NMR, 13C NMR, mass spectra and elemental analysis was followed by whole cell patch clamp assays for analyzing activity at Cav1.2 and Cav3.2. Two compounds were identified with significant activity against Cav1.2. Additionally, we identified four compounds active against Cav3.2 of which three were selective over Cav1.2. Novel binding modes were analyzed using docking and pharmacophore analysis as well as molecular dynamics simulations.}, keywords = {1,4-dihydropyridine Hexahydroquinoline Calcium channel Whole cell patch clamp Binding mechanism Molecular modelling}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2018.05.032}, url = {https://www.sciencedirect.com/science/article/pii/S0223523418304458 https://pdf.sciencedirectassets.com/271932/1-s2.0-S0223523418X00129/1-s2.0-S0223523418304458/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIQDpMFAxqO8i5cWwO8J2bidQOOPWWOgX2xYgjlCqnmYpKAIgMz6zEqJOOqjcysWG%2F%2BjDZIPEG4hPysl42TQ%2BxrkJgLgq2gMIQRACGgwwNTkwMDM1NDY4NjUiDMbVMeQJp%2BA6xuTeeiq3A5yGUmiSxbecX6zyK9C0u9d8FvveGrkPLG2bgf%2FLpoQrYo2WyvA%2BBWqUubZ%2F%2F2lzFcSTpeDFbT3qjC0N3gXJAnlrhfnB4HtdM5JkFOs7rk4T5uxWa2QB%2Bxrb0uGWp6C%2FKniuq6eBMiJ59EW8Qua9SC1HjapOsfuus9g5HoQTBdya%2B%2B93vPUyT1l6n3DvNF79aTePLdf4GzCoc3La3CqQwXZ%2Bv00XVVkSLXyHqEtn%2BKj4RqGYDx5vybmCYgNtuQnt%2F4u%2FKij1yfRzcl%2BKOheRiB2UBQBFkx%2BGRL%2BqBFLx23kYZU2PrVD4ZjQMMXyglfn7R41W1Ts944jcTs7eKtPEaIuwbGZFi3rfxU%2BBL%2BrhXsqDJMbPTE%2BrqYpk6xiwMVJaY6kJH62kCLazVZrQ49cjhJjxeJti4aqVRxjr4XOP%2FJ9EatP%2BZoD3q47yNzrS1dG3FcQOp6Rtx1LGD9QPU8GrLpoB2%2F%2BrydWuCVqCFWw5iNbyp05sWQsfmSpFEMzsvkKO%2FCw0bATpkHdkF6WOn0A1lXIOsI0cDUPAe1xWJ3L0KZySQ0UZUqXJ8Gw4v%2FTlL5BY%2FUxSnor26xYwn6aO6wU6tAHBqopuW5pcz%2FJI%2BrCyUdYGVL8ZGUcN9osxZNHlsdHl%2FPSb5Ey3HqdiHTks1pszrFK8F0ZxsQNCYajkgKT3SAzhgrTmaNYfXyzLVkl3rMbW5QA0SqgsnR79JfHgUXuHGBnWyrsVF5mu9vmFjpTB4j2VqmtMOIjghMdHO%2FOIcR59ey2VTJQKE1Ulq0WJqECO72nl8nHMFEUoBLcWlCu5cwJlo5NxAcL7qC1hNPBzJlNFYMqU07s%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090934Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY5J43SP76%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=c849855703227baf4068983f2ec0fd8823703c021692f5938ab30d1eb2fa9bff&hash=2b4e25a1b06c86632253879a8372204f4f5ae2a04e12ae7231cd5b4a48705142&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0223523418304458&tid=spdf-307057ac-8507-41f8-9a2e-60eca516f2bb&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2018}, type = {Journal Article} }  x  Binding mechanism investigations guiding the synthesis of novel condensed 1,4-dihydropyridine derivatives with L-/T-type calcium channel blocking activity

Nifedipine and isradipine are prominent examples of calcium channel blockers with a 1,4-dihydropyridine (DHP) scaffold. Although successfully used in clinics since decades for the treatment of hypertension, the binding mechanism to their target, the L-type voltage-gated calcium channel Cav1.2, is still incompletely understood. Recently, novel DHP derivatives with a condensed ring system have been discovered that show distinct selectivity profiles to different calcium channel subtypes. This property renders this DHP class as a promising tool to achieve selectivity towards distinct calcium channel subtypes. In this study, we identified a common binding mode for prominent DHPs nifedipine and isradipine using docking and pharmacophore analysis that is also able to explain the structure-activity relationship of a small subseries of DHP derivatives with a condensed ring system. These findings were used to guide the synthesis of twenty-two novel DHPs. An extensive characterization using 1H NMR, 13C NMR, mass spectra and elemental analysis was followed by whole cell patch clamp assays for analyzing activity at Cav1.2 and Cav3.2. Two compounds were identified with significant activity against Cav1.2. Additionally, we identified four compounds active against Cav3.2 of which three were selective over Cav1.2. Novel binding modes were analyzed using docking and pharmacophore analysis as well as molecular dynamics simulations.

[127]

R. Schulz, A. Atef, D. Becker, F. Gottschalk, C. Tauber, S. Wagner, C. Arkona, A. A. Abdel-Hafez, H. H. Farag, J. Rademann, and G. Wolber. Phenylthiomethyl ketone-based fragments show selective and irreversible inhibition of enteroviral 3C proteases, J Med Chem, 61(3):1218-1230, 2018.
Links: [doi:10.1021/acs.jmedchem.7b01440] [show BibTeX] [show abstract]  x  @article{RN252, author = {Schulz, Robert and Atef, Amira and Becker, Daniel and Gottschalk, Franziska and Tauber, Carolin and Wagner, Stefan and Arkona, Christoph and Abdel-Hafez, Atef A. and Farag, Hassan H. and Rademann, Jörg and Wolber, Gerhard}, title = {Phenylthiomethyl ketone-based fragments show selective and irreversible inhibition of enteroviral 3C proteases}, journal = {Journal of Medicinal Chemistry}, volume = {61}, number = {3}, pages = {1218-1230}, abstract = {Lead structure discovery mainly focuses on the identification of noncovalently binding ligands. Covalent linkage, however, is an essential binding mechanism for a multitude of successfully marketed drugs although discovered by serendipity in most cases. We present a concept for the design of fragments covalently binding to proteases. Covalent linkage enables fragment binding unrelated to affinity to shallow protein binding sites and at the same time allows differentiated targeted hit verification and binding location verification through mass spectrometry. We describe a systematic and rational computational approach for the identification of covalently binding fragments from compound collections inhibiting enteroviral 3C protease, a target with high therapeutic potential. By implementing reactive groups potentially forming covalent bonds as chemical feature in our 3D pharmacophore methodology, covalent binders were discovered by high-throughput virtual screening. We present careful experimental validation of the virtual hits using enzymatic assays and mass spectrometry unraveling a novel, previously unknown irreversible inhibition of the 3C protease by phenylthiomethyl ketone-based fragments. Subsequent synthetic optimization through fragment growing and reactivity analysis against catalytic and non-catalytic cysteines revealed specific irreversible 3C protease inhibition.}, ISSN = {0022-2623}, DOI = {10.1021/acs.jmedchem.7b01440}, url = {http://dx.doi.org/10.1021/acs.jmedchem.7b01440 https://pubs.acs.org/doi/pdfplus/10.1021/acs.jmedchem.7b01440}, year = {2018}, type = {Journal Article} }  x  Phenylthiomethyl ketone-based fragments show selective and irreversible inhibition of enteroviral 3C proteases

Lead structure discovery mainly focuses on the identification of noncovalently binding ligands. Covalent linkage, however, is an essential binding mechanism for a multitude of successfully marketed drugs although discovered by serendipity in most cases. We present a concept for the design of fragments covalently binding to proteases. Covalent linkage enables fragment binding unrelated to affinity to shallow protein binding sites and at the same time allows differentiated targeted hit verification and binding location verification through mass spectrometry. We describe a systematic and rational computational approach for the identification of covalently binding fragments from compound collections inhibiting enteroviral 3C protease, a target with high therapeutic potential. By implementing reactive groups potentially forming covalent bonds as chemical feature in our 3D pharmacophore methodology, covalent binders were discovered by high-throughput virtual screening. We present careful experimental validation of the virtual hits using enzymatic assays and mass spectrometry unraveling a novel, previously unknown irreversible inhibition of the 3C protease by phenylthiomethyl ketone-based fragments. Subsequent synthetic optimization through fragment growing and reactivity analysis against catalytic and non-catalytic cysteines revealed specific irreversible 3C protease inhibition.

[126]

A. Tkachenko, M. Bermudez, S. Irmer-Stooff, D. Genkinger, F. Henkler-Stephani, G. Wolber, and A. Luch. Nuclear transport of the human aryl hydrocarbon receptor and subsequent gene induction relies on its residue histidine 291, Arch Toxicol, 92(3):1151-1160, 2018.
Links: [doi:10.1007/s00204-017-2129-0] [show BibTeX] [show abstract]  x  @article{RN249, author = {Tkachenko, A. and Bermudez, M. and Irmer-Stooff, S. and Genkinger, D. and Henkler-Stephani, F. and Wolber, G. and Luch, A.}, title = {Nuclear transport of the human aryl hydrocarbon receptor and subsequent gene induction relies on its residue histidine 291}, journal = {Archives of Toxicology}, volume = {92}, number = {3}, pages = {1151-1160}, abstract = {The aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor involved in the metabolism of physiological substances and xenobiotics, representing an interesting target in both toxicology and pharmacology. In this study, we investigated the ligand-dependent conjunction of nuclear import of the human AHR in living cells and target gene induction. Our findings strengthen the theory that the AHR triggers a precisely defined and rapid reaction upon binding to endogenous ligands, while the xenobiotic β-naphthoflavone only induces rather unspecific and slow effects. To better illuminate the ligand-mediated responses of the human AHR, we applied site-directed mutagenesis and identified histidine 291 as key residue for AHR functionality, essential for both nuclear import and target gene induction. Contrary, replacing histidine at position 291 by alanine did not affect nucleo-cytoplasmic shuttling, showing that permanent endogenous import and ligand-induced import of the AHR into the nucleus are two independent and differently regulated processes. Combining these observations with our structural investigations using a homology model of the AHR-PAS B domain, we suggest a dual role of histidine 291: (1) a major role for shaping the ligand binding site including direct interactions with ligands and, (2) an essential role for the conformational dynamics of a PAS B loop, which most likely influences the association of the AHR with the AHR nuclear translocator through interference with their protein–protein interface.}, ISSN = {1432-0738}, DOI = {10.1007/s00204-017-2129-0}, url = {https://doi.org/10.1007/s00204-017-2129-0 https://link.springer.com/content/pdf/10.1007%2Fs00204-017-2129-0.pdf}, year = {2018}, type = {Journal Article} }  x  Nuclear transport of the human aryl hydrocarbon receptor and subsequent gene induction relies on its residue histidine 291

The aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor involved in the metabolism of physiological substances and xenobiotics, representing an interesting target in both toxicology and pharmacology. In this study, we investigated the ligand-dependent conjunction of nuclear import of the human AHR in living cells and target gene induction. Our findings strengthen the theory that the AHR triggers a precisely defined and rapid reaction upon binding to endogenous ligands, while the xenobiotic β-naphthoflavone only induces rather unspecific and slow effects. To better illuminate the ligand-mediated responses of the human AHR, we applied site-directed mutagenesis and identified histidine 291 as key residue for AHR functionality, essential for both nuclear import and target gene induction. Contrary, replacing histidine at position 291 by alanine did not affect nucleo-cytoplasmic shuttling, showing that permanent endogenous import and ligand-induced import of the AHR into the nucleus are two independent and differently regulated processes. Combining these observations with our structural investigations using a homology model of the AHR-PAS B domain, we suggest a dual role of histidine 291: (1) a major role for shaping the ligand binding site including direct interactions with ligands and, (2) an essential role for the conformational dynamics of a PAS B loop, which most likely influences the association of the AHR with the AHR nuclear translocator through interference with their protein–protein interface.

[125]

F. Yang, D. Machalz, S. Wang, Z. Li, G. Wolber, and M. Bureik. A common polymorphic variant of UGT1A5 displays increased activity due to optimized cofactor binding, Febs Lett, 592(11):1837-1846, 2018.
Links: [doi:10.1002/1873-3468.13072] [show BibTeX] [show abstract]  x  @article{RN259, author = {Yang, Fan and Machalz, David and Wang, Sisi and Li, Zhengyi and Wolber, Gerhard and Bureik, Matthias}, title = {A common polymorphic variant of UGT1A5 displays increased activity due to optimized cofactor binding}, journal = {FEBS Letters}, volume = {592}, number = {11}, pages = {1837-1846}, abstract = {Uridine diphosphate‐glucuronosyltransferases (UGTs) are the most important phase II enzymes in human drug metabolism. Using permeabilized recombinant fission yeast cells (enzyme bags), we demonstrate that UGT1A5 can catalyze an N‐glucuronidation reaction. We characterized two new polymorphic UGT1A5 variants: a common ninefold mutant (UGT1A5*8) with double‐fold activity and a much rarer sixfold mutant (UGT1A5*9), which has the same activity as the wild‐type. Molecular modeling studies indicate that the minor effects of all mutations, except for Gly259Arg, are due to their distance to the substrate binding site. Extensive molecular dynamics simulations revealed that the Gly259Arg mutation stabilizes helix Q through a newly formed hydrogen bonding network, which places the cofactor in a much more favorable geometry in UGT1A5*8 as compared to the wild‐type.}, DOI = {10.1002/1873-3468.13072}, url = {https://febs.onlinelibrary.wiley.com/doi/abs/10.1002/1873-3468.13072 https://febs.onlinelibrary.wiley.com/doi/pdf/10.1002/1873-3468.13072}, year = {2018}, type = {Journal Article} }  x  A common polymorphic variant of UGT1A5 displays increased activity due to optimized cofactor binding

Uridine diphosphate‐glucuronosyltransferases (UGTs) are the most important phase II enzymes in human drug metabolism. Using permeabilized recombinant fission yeast cells (enzyme bags), we demonstrate that UGT1A5 can catalyze an N‐glucuronidation reaction. We characterized two new polymorphic UGT1A5 variants: a common ninefold mutant (UGT1A5*8) with double‐fold activity and a much rarer sixfold mutant (UGT1A5*9), which has the same activity as the wild‐type. Molecular modeling studies indicate that the minor effects of all mutations, except for Gly259Arg, are due to their distance to the substrate binding site. Extensive molecular dynamics simulations revealed that the Gly259Arg mutation stabilizes helix Q through a newly formed hydrogen bonding network, which places the cofactor in a much more favorable geometry in UGT1A5*8 as compared to the wild‐type.

[124]

H. A. Abuelizz, R. Al-Salahi, J. Al-Asri, J. Mortier, M. Marzouk, E. Ezzeldin, A. A. Ali, M. G. Khalil, G. Wolber, H. A. Ghabbour, A. A. Almehizia, and G. A. Abdel Jaleel. Synthesis, crystallographic characterization, molecular docking and biological activity of isoquinoline derivatives, Chem Cent J, 11(1):103, 2017.
Links: [doi:10.1186/s13065-017-0321-1] [show BibTeX] [show abstract]  x  @article{RN207, author = {Abuelizz, Hatem A. and Al-Salahi, Rashad and Al-Asri, Jamil and Mortier, Jérémie and Marzouk, Mohamed and Ezzeldin, Essam and Ali, Azza A. and Khalil, Mona G. and Wolber, Gerhard and Ghabbour, Hazem A. and Almehizia, Abdulrahman A. and Abdel Jaleel, Gehad A.}, title = {Synthesis, crystallographic characterization, molecular docking and biological activity of isoquinoline derivatives}, journal = {Chemistry Central Journal}, volume = {11}, number = {1}, pages = {103}, abstract = {The main objective of this work was to synthesize novel compounds with a benzo[de][1,2,4]triazolo[5,1-a]isoquinoline scaffold by employing (dioxo-benzo[de]isoquinolin-2-yl) thiourea as a building block. Molecular docking was conducted in the COX-2 active site to predict the plausible binding mode and rationalize the structure–activity relationship of the synthesized compounds. The structures of the synthesized compounds were confirmed by HREI-MS, and NMR spectra along with X-ray diffraction were collected for products 1 and 5. Thereafter, anti-inflammatory effect of molecules 1–20 was evaluated in vivo using carrageenan-induced paw edema method, revealing significant inhibition potency in albino rats with an activity comparable to that of the standard drugs indomethacin. Compounds 8, 9, 15 and 16 showed the highest anti-inflammatory activity. However, thermal sensitivity-hot plat test, a radiological examination and motor coordination assessment were performed to test the activity against rheumatoid arthritis. The obtained results indicate promising anti-arthritic activity for compounds 9 and 15 as significant reduction of the serum level of interleukin-1β [IL-1β], cyclooxygenase-2 [COX-2] and prostaglandin E2 [PGE2] was observed in CFA rats.}, ISSN = {1752-153X}, DOI = {10.1186/s13065-017-0321-1}, url = {https://doi.org/10.1186/s13065-017-0321-1 https://ccj.springeropen.com/track/pdf/10.1186/s13065-017-0321-1?site= ccj.springeropen.com}, year = {2017}, type = {Journal Article} }  x  Synthesis, crystallographic characterization, molecular docking and biological activity of isoquinoline derivatives

The main objective of this work was to synthesize novel compounds with a benzo[de][1,2,4]triazolo[5,1-a]isoquinoline scaffold by employing (dioxo-benzo[de]isoquinolin-2-yl) thiourea as a building block. Molecular docking was conducted in the COX-2 active site to predict the plausible binding mode and rationalize the structure–activity relationship of the synthesized compounds. The structures of the synthesized compounds were confirmed by HREI-MS, and NMR spectra along with X-ray diffraction were collected for products 1 and 5. Thereafter, anti-inflammatory effect of molecules 1–20 was evaluated in vivo using carrageenan-induced paw edema method, revealing significant inhibition potency in albino rats with an activity comparable to that of the standard drugs indomethacin. Compounds 8, 9, 15 and 16 showed the highest anti-inflammatory activity. However, thermal sensitivity-hot plat test, a radiological examination and motor coordination assessment were performed to test the activity against rheumatoid arthritis. The obtained results indicate promising anti-arthritic activity for compounds 9 and 15 as significant reduction of the serum level of interleukin-1β [IL-1β], cyclooxygenase-2 [COX-2] and prostaglandin E2 [PGE2] was observed in CFA rats.

[123]

M. Bermudez, A. Bock, F. Krebs, U. Holzgrabe, K. Mohr, M. J. Lohse, and G. Wolber. Ligand-specific restriction of extracellular conformational dynamics constrains signaling of the M2 muscarinic receptor, ACS Chem Biol, 12(7):1743-1748, 2017.
Links: [doi:10.1021/acschembio.7b00275] [show BibTeX] [show abstract]  x  @article{RN203, author = {Bermudez, Marcel and Bock, Andreas and Krebs, Fabian and Holzgrabe, Ulrike and Mohr, Klaus and Lohse, Martin J. and Wolber, Gerhard}, title = {Ligand-specific restriction of extracellular conformational dynamics constrains signaling of the M2 muscarinic receptor}, journal = {ACS Chemical Biology}, volume = {12}, number = {7}, pages = {1743-1748}, abstract = {G protein-coupled receptors transmit extracellular signals across cell membranes via different G protein classes and β-arrestins. Some pathways may be therapeutically beneficial, whereas others may be detrimental under certain pathophysiological conditions. For many GPCRs, biased agonists are available, which preferentially signal through one pathway or a subset of pathways, and harnessing biased agonism could be a potential novel therapeutic strategy. However, the incomplete mechanistic understanding of biased agonism hampers rational design of biased ligands. Using the muscarinic M2 receptor as a model system, we have analyzed the relationship between ligand-dependent conformational changes as revealed in all-atom MD simulations and the activation of specific G proteins. We find that the extent of closure of the extracellular, allosteric binding site interferes with the activation of certain G proteins. Our data allow the rational design of Gi-biased agonists at the M2 receptor and delineate a simple principle which may be translated to other GPRCs.}, keywords = {gpcr}, DOI = {10.1021/acschembio.7b00275}, url = {http://pubs.acs.org/doi/pdfplus/10.1021/acschembio.7b00275}, year = {2017}, type = {Journal Article} }  x  Ligand-specific restriction of extracellular conformational dynamics constrains signaling of the M2 muscarinic receptor

G protein-coupled receptors transmit extracellular signals across cell membranes via different G protein classes and β-arrestins. Some pathways may be therapeutically beneficial, whereas others may be detrimental under certain pathophysiological conditions. For many GPCRs, biased agonists are available, which preferentially signal through one pathway or a subset of pathways, and harnessing biased agonism could be a potential novel therapeutic strategy. However, the incomplete mechanistic understanding of biased agonism hampers rational design of biased ligands. Using the muscarinic M2 receptor as a model system, we have analyzed the relationship between ligand-dependent conformational changes as revealed in all-atom MD simulations and the activation of specific G proteins. We find that the extent of closure of the extracellular, allosteric binding site interferes with the activation of certain G proteins. Our data allow the rational design of Gi-biased agonists at the M2 receptor and delineate a simple principle which may be translated to other GPRCs.

[122]

J. Mortier, J. R. C. Prévost, D. Sydow, S. Teuchert, C. Omieczynski, M. Bermudez, R. Frédérick, and G. Wolber. Arginase structure and inhibition: Catalytic site plasticity reveals new modulation possibilities, Scientific Reports, 7(1):13616, 2017.
Links: [doi:10.1038/s41598-017-13366-4] [show BibTeX] [show abstract]  x  @article{RN248, author = {Mortier, Jérémie and Prévost, Julien R. C. and Sydow, Dominique and Teuchert, Sabine and Omieczynski, Christian and Bermudez, Marcel and Frédérick, Raphaël and Wolber, Gerhard}, title = {Arginase structure and inhibition: Catalytic site plasticity reveals new modulation possibilities}, journal = {Scientific Reports}, volume = {7}, number = {1}, pages = {13616}, abstract = {Metalloenzyme arginase is a therapeutically relevant target associated with tumor growth. To fight cancer immunosuppression, arginase activity can be modulated by small chemical inhibitors binding to its catalytic center. To better understand molecular mechanisms of arginase inhibition, a careful computer-aided mechanistic structural investigation of this enzyme was conducted. Using molecular dynamics (MD) simulations in the microsecond range, key regions of the protein active site were identified and their flexibility was evaluated and compared. A cavity opening phenomenon was observed, involving three loops directly interacting with all known ligands, while metal coordinating regions remained motionless. A novel dynamic 3D pharmacophore analysis method termed dynophores has been developed that allows for the construction of a single 3D-model comprising all ligand-enzyme interactions occurring throughout a complete MD trajectory. This new technique for the in silico study of intermolecular interactions allows for loop flexibility analysis coupled with movements and conformational changes of bound ligands. Presented MD studies highlight the plasticity of the size of the arginase active site, leading to the hypothesis that larger ligands can enter the cavity of arginase. Experimental testing of a targeted fragment library substituted by different aliphatic groups validates this hypothesis, paving the way for the design of arginase inhibitors with novel binding patterns.}, keywords = {dynophore}, ISSN = {2045-2322}, DOI = {10.1038/s41598-017-13366-4}, url = {https://doi.org/10.1038/s41598-017-13366-4 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5648838/pdf/41598_2017_Article_13366.pdf}, year = {2017}, type = {Journal Article} }  x  Arginase structure and inhibition: Catalytic site plasticity reveals new modulation possibilities

Metalloenzyme arginase is a therapeutically relevant target associated with tumor growth. To fight cancer immunosuppression, arginase activity can be modulated by small chemical inhibitors binding to its catalytic center. To better understand molecular mechanisms of arginase inhibition, a careful computer-aided mechanistic structural investigation of this enzyme was conducted. Using molecular dynamics (MD) simulations in the microsecond range, key regions of the protein active site were identified and their flexibility was evaluated and compared. A cavity opening phenomenon was observed, involving three loops directly interacting with all known ligands, while metal coordinating regions remained motionless. A novel dynamic 3D pharmacophore analysis method termed dynophores has been developed that allows for the construction of a single 3D-model comprising all ligand-enzyme interactions occurring throughout a complete MD trajectory. This new technique for the in silico study of intermolecular interactions allows for loop flexibility analysis coupled with movements and conformational changes of bound ligands. Presented MD studies highlight the plasticity of the size of the arginase active site, leading to the hypothesis that larger ligands can enter the cavity of arginase. Experimental testing of a targeted fragment library substituted by different aliphatic groups validates this hypothesis, paving the way for the design of arginase inhibitors with novel binding patterns.

[121]

M. S. Murgueitio, S. Ebner, P. Hörtnagl, C. Rakers, R. Bruckner, P. Henneke, G. Wolber, and S. Santos-Sierra. Enhanced immunostimulatory activity of in silico discovered agonists of Toll-like receptor 2 (TLR2), Biochimica et Biophysica Acta (BBA), General Subjects, 1861(11):2680-2689, 2017.
Links: [doi:10.1016/j.bbagen.2017.07.011] [show BibTeX] [show abstract]  x  @article{RN205, author = {Murgueitio, M. S. and Ebner, S. and Hörtnagl, P. and Rakers, C. and Bruckner, R. and Henneke, P. and Wolber, G. and Santos-Sierra, S.}, title = {Enhanced immunostimulatory activity of in silico discovered agonists of Toll-like receptor 2 (TLR2)}, journal = {Biochimica et Biophysica Acta (BBA), General Subjects}, volume = {1861}, number = {11}, pages = {2680-2689}, abstract = {Emergent therapies in anticancer vaccination use Toll-like receptors (TLRs) agonists as dendritic cell (DC) vaccine adjuvants. DCs from the patient are isolated, stimulated with TLR agonists and tumor antigens ex vivo and then infused back into the patient. Although some TLR ligands have been tested in clinical trials, novel TLR agonists with improved immunomodulatory properties are essential to optimize treatment success. We report on the discovery of small-molecule TLR2 agonists, with favorable properties as synthetic adjuvants. We performed a shape- and featured-based similarity virtual screening against a commercially available compound library. The selected virtual hits were experimentally tested in TLR2-reporter cells and their activity in phagocytes and DCs was characterized. A binding model of the compounds to TLR2 (docking studies) was proposed. Through a virtual screening approach against a library of three million compounds four virtual hits (AG1, AG2, AG3, AG4) were found to synergistically augment the NF-kB activation induced by the lipopeptide ligand Pam3CSK4 in luciferase reporter assays using HEK293-TLR2 cells. Biacore experiments indicated that AG1–AG4 are ago-allosteric modulators of TLR2 and AG2 bound TLR2 with high affinity (KD 0.8μM). The compounds induced TNF-α production in human peripheral blood mononuclear cells (PBMCs) and they activated DCs as indicated by IL-12 production and upregulation of CD83/CD86. Following a combined in silico/in vitro approach we have discovered TLR2-agonists (AG1–AG4) that activate human and mouse immune cells. We introduce four novel TLR2 ago-allosteric modulators that stimulate myeloid cell activity and constitute promising candidates as synthetic adjuvants.}, keywords = {Toll-like receptor Cancer vaccination Virtual screening Adjuvants Dendritic cell Inflammation}, ISSN = {0304-4165}, DOI = {10.1016/j.bbagen.2017.07.011}, url = {http://www.sciencedirect.com/science/article/pii/S0304416517302222 https://ac.els-cdn.com/S0304416517302222/1-s2.0-S0304416517302222-main.pdf?_tid= 0e5b1604-ba65-11e7-9947-00000aab0f27&acdnat=1509033065_be28cc321c81e00bd2ec48eb34559e40}, year = {2017}, type = {Journal Article} }  x  Enhanced immunostimulatory activity of in silico discovered agonists of Toll-like receptor 2 (TLR2)

Emergent therapies in anticancer vaccination use Toll-like receptors (TLRs) agonists as dendritic cell (DC) vaccine adjuvants. DCs from the patient are isolated, stimulated with TLR agonists and tumor antigens ex vivo and then infused back into the patient. Although some TLR ligands have been tested in clinical trials, novel TLR agonists with improved immunomodulatory properties are essential to optimize treatment success. We report on the discovery of small-molecule TLR2 agonists, with favorable properties as synthetic adjuvants. We performed a shape- and featured-based similarity virtual screening against a commercially available compound library. The selected virtual hits were experimentally tested in TLR2-reporter cells and their activity in phagocytes and DCs was characterized. A binding model of the compounds to TLR2 (docking studies) was proposed. Through a virtual screening approach against a library of three million compounds four virtual hits (AG1, AG2, AG3, AG4) were found to synergistically augment the NF-kB activation induced by the lipopeptide ligand Pam3CSK4 in luciferase reporter assays using HEK293-TLR2 cells. Biacore experiments indicated that AG1–AG4 are ago-allosteric modulators of TLR2 and AG2 bound TLR2 with high affinity (KD 0.8μM). The compounds induced TNF-α production in human peripheral blood mononuclear cells (PBMCs) and they activated DCs as indicated by IL-12 production and upregulation of CD83/CD86. Following a combined in silico/in vitro approach we have discovered TLR2-agonists (AG1–AG4) that activate human and mouse immune cells. We introduce four novel TLR2 ago-allosteric modulators that stimulate myeloid cell activity and constitute promising candidates as synthetic adjuvants.

[120]

M. S. Murgueitio, C. Rakers, A. Frank, and G. Wolber. Balancing Inflammation: Computational Design of Small-Molecule Toll-like Receptor Modulators, Trends Pharmacol Sci, 38(2):155-168, 2017.
Links: [doi:10.1016/j.tips.2016.10.007] [show BibTeX] [show abstract]  x  @article{RN201, author = {Murgueitio, Manuela S. and Rakers, Christin and Frank, Anne and Wolber, Gerhard}, title = {Balancing Inflammation: Computational Design of Small-Molecule Toll-like Receptor Modulators}, journal = {Trends in Pharmacological Sciences}, volume = {38}, number = {2}, pages = {155-168}, abstract = {As essential proteins of the innate immune system, Toll-like receptors (TLRs) are involved in a plethora of physiological pathologies and their modulation is an ongoing quest in the field of drug discovery. Although TLRs recognize an unusually broad range of different molecular patterns, only a few small-molecule TLR modulators have been reported to date. Recent advances in crystallography and in silico techniques provide promising opportunities for TLR investigations and drug design. Here, three application areas for computational approaches are considered: (i) exploration of TLR structure and activation; (ii) understanding TLR modulation; and (iii) TLR drug discovery. By providing an overview on state-of-the-art computational methods, we highlight the value of molecular modeling in mechanistically understanding TLR function and guiding drug design.}, ISSN = {0165-6147}, DOI = {10.1016/j.tips.2016.10.007}, url = {http://dx.doi.org/10.1016/j.tips.2016.10.007 http://ac.els-cdn.com/S0165614716301377/1-s2.0-S0165614716301377-main.pdf?_tid= 8ea85ae0-b7c0-11e6-8b76-00000aab0f27&acdnat=1480595013_5bb0b3aaeb0d4f16e65dd6468b9b7091}, year = {2017}, type = {Journal Article} }  x  Balancing Inflammation: Computational Design of Small-Molecule Toll-like Receptor Modulators

As essential proteins of the innate immune system, Toll-like receptors (TLRs) are involved in a plethora of physiological pathologies and their modulation is an ongoing quest in the field of drug discovery. Although TLRs recognize an unusually broad range of different molecular patterns, only a few small-molecule TLR modulators have been reported to date. Recent advances in crystallography and in silico techniques provide promising opportunities for TLR investigations and drug design. Here, three application areas for computational approaches are considered: (i) exploration of TLR structure and activation; (ii) understanding TLR modulation; and (iii) TLR drug discovery. By providing an overview on state-of-the-art computational methods, we highlight the value of molecular modeling in mechanistically understanding TLR function and guiding drug design.

[119]

R. Ottana, P. Paoli, A. Naß, G. Lori, V. Cardile, I. Adornato, A. Rotondo, A. C. Eleonora Graziano, G. Wolber, and R. Maccari. Discovery of 4-[(5-arylidene-4-oxothiazolidin-3-yl)methyl]benzoic acid derivatives active as novel potent allosteric inhibitors of protein tyrosine phosphatase 1B: In silico studies and in vitro evaluation as insulinomimetic and anti-inflammatory agents, Eur J Med Chem, 127:840-858, 2017.
Links: [doi:10.1016/j.ejmech.2016.10.063] [show BibTeX] [show abstract]  x  @article{RN199, author = {Ottana, Rosaria and Paoli, Paolo and Naß, Alexandra and Lori, Giulia and Cardile, Venera and Adornato, Ilenia and Rotondo, Archimede and Eleonora Graziano, Adriana Carol and Wolber, Gerhard and Maccari, Rosanna}, title = {Discovery of 4-[(5-arylidene-4-oxothiazolidin-3-yl)methyl]benzoic acid derivatives active as novel potent allosteric inhibitors of protein tyrosine phosphatase 1B: In silico studies and in vitro evaluation as insulinomimetic and anti-inflammatory agents}, journal = {European Journal of Medicinal Chemistry}, volume = {127}, pages = {840-858}, abstract = {New 4-{[5-arylidene-2-(4-fluorophenylimino)-4-oxothiazolidin-3-yl]methyl}benzoic acids (5) and 2-thioxo-4-thiazolidinone analogues (6) were synthesised as a part of a continuing search for new inhibitors of protein tyrosine phosphatase 1B (PTP1B), an enzyme which is implicated in metabolic disorders and inflammatory signaling. Most of the tested compounds were shown to be potent PTP1B inhibitors. Moreover, their inhibition mechanism was markedly influenced by the substituents in the positions 2 and 5, as kinetic studies indicated. Docking experiments suggested that certain derivatives 5 and 6 may efficiently fit into an allosteric site positioned between the β-sheet including Leu71 and Lys73 and a lipophilic pocket closed by the loop consisting of Pro210 to Leu 204. In cellular assays, several of these new 4-thiazolidinone derivatives showed insulinomimetic and anti-inflammatory properties. Out of them, compound 5b exhibited the most promising profile, being able to promote the activation of both insulin receptor and downstream Akt protein as well as to increase 2-deoxyglucose cellular uptake. Interestingly, compound 5b was also able to interrupt critical events in inflammatory signalling.}, keywords = {Protein tyrosine phosphatases Enzyme inhibitors Insulinomimetic effects Anti-inflammatory activity Molecular docking 5-Arylidene-4-thiazolidinone derivatives}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2016.10.063}, url = {http://www.sciencedirect.com/science/article/pii/S0223523416309345 http://ac.els-cdn.com/S0223523416309345/1-s2.0-S0223523416309345-main.pdf?_tid= 72e236fe-ed3b-11e6-8bc2-00000aab0f6c&acdnat=1486475206_d6dd5764eee03f4148356c005814f688}, year = {2017}, type = {Journal Article} }  x  Discovery of 4-[(5-arylidene-4-oxothiazolidin-3-yl)methyl]benzoic acid derivatives active as novel potent allosteric inhibitors of protein tyrosine phosphatase 1B: In silico studies and in vitro evaluation as insulinomimetic and anti-inflammatory agents

New 4-{[5-arylidene-2-(4-fluorophenylimino)-4-oxothiazolidin-3-yl]methyl}benzoic acids (5) and 2-thioxo-4-thiazolidinone analogues (6) were synthesised as a part of a continuing search for new inhibitors of protein tyrosine phosphatase 1B (PTP1B), an enzyme which is implicated in metabolic disorders and inflammatory signaling. Most of the tested compounds were shown to be potent PTP1B inhibitors. Moreover, their inhibition mechanism was markedly influenced by the substituents in the positions 2 and 5, as kinetic studies indicated. Docking experiments suggested that certain derivatives 5 and 6 may efficiently fit into an allosteric site positioned between the β-sheet including Leu71 and Lys73 and a lipophilic pocket closed by the loop consisting of Pro210 to Leu 204. In cellular assays, several of these new 4-thiazolidinone derivatives showed insulinomimetic and anti-inflammatory properties. Out of them, compound 5b exhibited the most promising profile, being able to promote the activation of both insulin receptor and downstream Akt protein as well as to increase 2-deoxyglucose cellular uptake. Interestingly, compound 5b was also able to interrupt critical events in inflammatory signalling.

[118]

F. Sanz, F. Pognan, T. Steger-Hartmann, C. Díaz, M. Cases, M. Pastor, P. Marc, J. Wichard, K. Briggs, D. K. Watson, T. Kleinöder, C. Yang, A. Amberg, M. Beaumont, A. J. Brookes, S. Brunak, M. T. D. Cronin, G. F. Ecker, S. Escher, N. Greene, A. Guzmán, A. Hersey, P. Jacques, L. Lammens, J. Mestres, W. Muster, H. Northeved, M. Pinches, J. Saiz, N. Sajot, A. Valencia, J. van der Lei, N. P. E. Vermeulen, E. Vock, G. Wolber, and I. Zamora. Legacy data sharing to improve drug safety assessment: the eTOX project, Nat Rev Drug Discov, 16:811, 2017.
Links: [doi:10.1038/nrd.2017.177] [show BibTeX]  x  @article{RN250, author = {Sanz, Ferran and Pognan, François and Steger-Hartmann, Thomas and Díaz, Carlos and Cases, Montserrat and Pastor, Manuel and Marc, Philippe and Wichard, Joerg and Briggs, Katharine and Watson, David K. and Kleinöder, Thomas and Yang, Chihae and Amberg, Alexander and Beaumont, Maria and Brookes, Anthony J. and Brunak, Søren and Cronin, Mark T. D. and Ecker, Gerhard F. and Escher, Sylvia and Greene, Nigel and Guzmán, Antonio and Hersey, Anne and Jacques, Pascale and Lammens, Lieve and Mestres, Jordi and Muster, Wolfgang and Northeved, Helle and Pinches, Marc and Saiz, Javier and Sajot, Nicolas and Valencia, Alfonso and van der Lei, Johan and Vermeulen, Nico P. E. and Vock, Esther and Wolber, Gerhard and Zamora, Ismael}, title = {Legacy data sharing to improve drug safety assessment: the eTOX project}, journal = {Nature Reviews Drug Discovery}, volume = {16}, pages = {811}, DOI = {10.1038/nrd.2017.177}, url = {http://dx.doi.org/10.1038/nrd.2017.177 http://www.nature.com/articles/nrd.2017.177.pdf}, year = {2017}, type = {Journal Article} }

[117]

D. Schaller, S. Hagenow, G. Alpert, A. Naß, R. Schulz, M. Bermudez, H. Stark, and G. Wolber. Systematic data mining reveals synergistic H3R/MCHR1 ligands, ACS Medicinal Chemistry Letters, 8(6):648-653, 2017.
Links: [doi:10.1021/acsmedchemlett.7b00118] [show BibTeX] [show abstract]  x  @article{RN202, author = {Schaller, David and Hagenow, Stefanie and Alpert, Gina and Naß, Alexandra and Schulz, Robert and Bermudez, Marcel and Stark, Holger and Wolber, Gerhard}, title = {Systematic data mining reveals synergistic H3R/MCHR1 ligands}, journal = {ACS Medicinal Chemistry Letters}, volume = {8}, number = {6}, pages = {648-653}, abstract = {In this study, we report a ligand-centric data mining approach that guided the identification of suitable target profiles for treating obesity. The newly developed method is based on identifying target pairs for synergistic positive effects and also encompasses the exclusion of compounds showing a detrimental effect on obesity treatment (off-targets). Ligands with known activity against obesity-relevant targets were compared using fingerprint representations. Similar compounds with activities to different targets were evaluated for the mechanism of action since activation or deactivation of drug targets determines the pharmacological effect. In vitro validation of the modeling results revealed that three known modulators of melanin-concentrating hormone receptor 1 (MCHR1) show a previously unknown submicromolar affinity to the histamine H3 receptor (H3R). This synergistic activity may present a novel therapeutic option against obesity.}, keywords = {gpcr}, DOI = {10.1021/acsmedchemlett.7b00118}, url = {http://dx.doi.org/10.1021/acsmedchemlett.7b00118 http://pubs.acs.org/doi/pdfplus/10.1021/acsmedchemlett.7b00118}, year = {2017}, type = {Journal Article} }  x  Systematic data mining reveals synergistic H3R/MCHR1 ligands

In this study, we report a ligand-centric data mining approach that guided the identification of suitable target profiles for treating obesity. The newly developed method is based on identifying target pairs for synergistic positive effects and also encompasses the exclusion of compounds showing a detrimental effect on obesity treatment (off-targets). Ligands with known activity against obesity-relevant targets were compared using fingerprint representations. Similar compounds with activities to different targets were evaluated for the mechanism of action since activation or deactivation of drug targets determines the pharmacological effect. In vitro validation of the modeling results revealed that three known modulators of melanin-concentrating hormone receptor 1 (MCHR1) show a previously unknown submicromolar affinity to the histamine H3 receptor (H3R). This synergistic activity may present a novel therapeutic option against obesity.

[116]

Q. Yan, D. Machalz, A. Zöllner, E. J. Sorensen, G. Wolber, and M. Bureik. Efficient substrate screening and inhibitor testing of human CYP4Z1 using permeabilized recombinant fission yeast, Biochem Pharmacol, 146:174-187, 2017.
Links: [doi:10.1016/j.bcp.2017.09.011] [show BibTeX] [show abstract]  x  @article{RN206, author = {Yan, Qi and Machalz, David and Zöllner, Andy and Sorensen, Erik J. and Wolber, Gerhard and Bureik, Matthias}, title = {Efficient substrate screening and inhibitor testing of human CYP4Z1 using permeabilized recombinant fission yeast}, journal = {Biochemical Pharmacology}, volume = {146}, pages = {174-187}, abstract = {We have established a protocol for the preparation of permeabilized fission yeast cells (enzyme bags) that recombinantly express human cytochrome P450 enzymes (CYPs). A direct comparison of CYP3A4 activity gave an eightfold higher space-time yield for enzyme bag-catalyzed biotransformation as compared to whole-cell biotransformation, even though the total number of cells employed was lower by a factor of 150. Biotransformation of the luminogenic substrate Luciferin-H using CYP2C9-containing enzyme bags proceeded efficiently and stably for 24h. CYP4Z1 is of interest because it is strongly overexpressed both in breast cancer cells and in breast cancer metastases; however, current knowledge about its catalytic properties is very limited. Screening of CYP4Z1-containing enzyme bags with 15 luminogenic substrates enabled us to identify two new hydroxylations and eleven ether cleavage reactions that are catalyzed by CYP4Z1. By far the best substrate found in this study was Luciferin benzyl ether (Luciferin-BE). On the basis of the recently published crystal structure of CYP4B1 we created a new homology model of CYP4Z1 and performed molecular docking experiments, which indicate that all active substrates show a highly similar binding geometry compared to the endogenous substrates. The model predicts that Ser113, Ser222, Asn381, and Ser383 are key hydrogen bonding residues. We also identified five new inhibitors of CYP4Z1: miconazole, econazole, aminobenzotriazole, tolazoline, and 1-benzylimidazole respectively, with the last compound being the most potent giving an IC50 value of 180nM in our test system.}, keywords = {Human cytochrome P450 Biotransformation Fission yeast Hydroxylation Ether cleavage}, ISSN = {0006-2952}, DOI = {10.1016/j.bcp.2017.09.011}, url = {http://www.sciencedirect.com/science/article/pii/S000629521730607X}, year = {2017}, type = {Journal Article} }  x  Efficient substrate screening and inhibitor testing of human CYP4Z1 using permeabilized recombinant fission yeast

We have established a protocol for the preparation of permeabilized fission yeast cells (enzyme bags) that recombinantly express human cytochrome P450 enzymes (CYPs). A direct comparison of CYP3A4 activity gave an eightfold higher space-time yield for enzyme bag-catalyzed biotransformation as compared to whole-cell biotransformation, even though the total number of cells employed was lower by a factor of 150. Biotransformation of the luminogenic substrate Luciferin-H using CYP2C9-containing enzyme bags proceeded efficiently and stably for 24h. CYP4Z1 is of interest because it is strongly overexpressed both in breast cancer cells and in breast cancer metastases; however, current knowledge about its catalytic properties is very limited. Screening of CYP4Z1-containing enzyme bags with 15 luminogenic substrates enabled us to identify two new hydroxylations and eleven ether cleavage reactions that are catalyzed by CYP4Z1. By far the best substrate found in this study was Luciferin benzyl ether (Luciferin-BE). On the basis of the recently published crystal structure of CYP4B1 we created a new homology model of CYP4Z1 and performed molecular docking experiments, which indicate that all active substrates show a highly similar binding geometry compared to the endogenous substrates. The model predicts that Ser113, Ser222, Asn381, and Ser383 are key hydrogen bonding residues. We also identified five new inhibitors of CYP4Z1: miconazole, econazole, aminobenzotriazole, tolazoline, and 1-benzylimidazole respectively, with the last compound being the most potent giving an IC50 value of 180nM in our test system.

[115]

J. Al-Asri, G. Gyémánt, E. Fazekas, G. Lehoczki, M. F. Melzig, G. Wolber, and J. Mortier. α-Amylase Modulation: Discovery of Inhibitors Using a Multi-Pharmacophore Approach for Virtual Screening, ChemMedChem, 11(21):2372-2377, 2016.
Links: [doi:10.1002/cmdc.201600427] [show BibTeX] [show abstract]  x  @article{RN200, author = {Al-Asri, Jamil and Gyémánt, Gyöngyi and Fazekas, Erika and Lehoczki, Gábor and Melzig, Matthias F. and Wolber, Gerhard and Mortier, Jérémie}, title = {α-Amylase Modulation: Discovery of Inhibitors Using a Multi-Pharmacophore Approach for Virtual Screening}, journal = {ChemMedChem}, volume = {11}, number = {21}, pages = {2372-2377}, abstract = {Better control of postprandial hyperglycemia can be achieved by delaying the absorption of glucose resulting from carbohydrate digestion. Because α-amylase initiates the hydrolysis of polysaccharides, the design of α-amylase inhibitors can lead to the development of new treatments for metabolic disorders such as type II diabetes and obesity. In this study, a rational computer-aided approach was developed to identify novel α-amylase inhibitors. Three-dimensional pharmacophores were developed based on the binding mode analysis of six different families of compounds that bind to this enzyme. In a stepwise virtual screening workflow, seven molecules were selected from a library of 1.4 million. Five out of seven biologically tested compounds showed α-amylase inhibition, and the two most potent compounds inhibited α-amylase with IC50 values of 17 and 27 μm. The scaffold benzylideneacetohydrazide was shared by four of the discovered inhibitors, emerging as a novel drug-like non-carbohydrate fragment and constituting a promising lead scaffold for α-amylase inhibition.}, keywords = {α-amylase computer-aided drug design diabetes high-throughput virtual screening lead discovery obesity}, ISSN = {1860-7187}, DOI = {10.1002/cmdc.201600427}, url = {http://dx.doi.org/10.1002/cmdc.201600427 http://onlinelibrary.wiley.com/store/10.1002/cmdc.201600427/asset/cmdc201600427.pdf?v= 1&t=iw6bvytr&s=b1ae9a27fb0f290b45c6a6997a8a3e9dff7b9678}, year = {2016}, type = {Journal Article} }  x  α-Amylase Modulation: Discovery of Inhibitors Using a Multi-Pharmacophore Approach for Virtual Screening

Better control of postprandial hyperglycemia can be achieved by delaying the absorption of glucose resulting from carbohydrate digestion. Because α-amylase initiates the hydrolysis of polysaccharides, the design of α-amylase inhibitors can lead to the development of new treatments for metabolic disorders such as type II diabetes and obesity. In this study, a rational computer-aided approach was developed to identify novel α-amylase inhibitors. Three-dimensional pharmacophores were developed based on the binding mode analysis of six different families of compounds that bind to this enzyme. In a stepwise virtual screening workflow, seven molecules were selected from a library of 1.4 million. Five out of seven biologically tested compounds showed α-amylase inhibition, and the two most potent compounds inhibited α-amylase with IC50 values of 17 and 27 μm. The scaffold benzylideneacetohydrazide was shared by four of the discovered inhibitors, emerging as a novel drug-like non-carbohydrate fragment and constituting a promising lead scaffold for α-amylase inhibition.

[114]

D. Becker, Z. Kaczmarska, C. Arkona, R. Schulz, C. Tauber, G. Wolber, R. Hilgenfeld, M. Coll, and J. Rademann. Irreversible inhibitors of the 3C protease of Coxsackie virus through templated assembly of protein-binding fragments, Nat Commun, 7:12761, 2016.
Links: [doi:10.1038/ncomms12761] [show BibTeX]  x  @article{RN198, author = {Becker, Daniel and Kaczmarska, Zuzanna and Arkona, Christoph and Schulz, Robert and Tauber, Carolin and Wolber, Gerhard and Hilgenfeld, Rolf and Coll, Miquel and Rademann, Jörg}, title = {Irreversible inhibitors of the 3C protease of Coxsackie virus through templated assembly of protein-binding fragments}, journal = {Nature Communications}, volume = {7}, pages = {12761}, DOI = {10.1038/ncomms12761}, url = {http://dx.doi.org/10.1038/ncomms12761 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5052702/pdf/ncomms12761.pdf}, year = {2016}, type = {Journal Article} }

[113]

M. Bermudez, J. Mortier, C. Rakers, D. Sydow, and G. Wolber. More than a look into a crystal ball: protein structure elucidation guided by molecular dynamics simulations, Drug Discov Today, 21(11):1799-1805, 2016.
Links: [doi:10.1016/j.drudis.2016.07.001] [show BibTeX] [show abstract]  x  @article{RN193, author = {Bermudez, Marcel and Mortier, Jeremie and Rakers, Christin and Sydow, Dominique and Wolber, Gerhard}, title = {More than a look into a crystal ball: protein structure elucidation guided by molecular dynamics simulations}, journal = {Drug Discovery Today}, volume = {21}, number = {11}, pages = {1799-1805}, abstract = {The ‘form follows function’ principle implies that a structural determination of protein structures is indispensable to understand proteins in their biological roles. However, experimental methods still show shortcomings in the description of the dynamic properties of proteins. Therefore, molecular dynamics (MD) simulations represent an essential tool for structural biology to investigate proteins as flexible and dynamic entities. Here, we will give an overview on the impact of MD simulations on structural investigations, including studies that aim at a prediction of protein-folding pathways, protein-assembly processes and the sampling of conformational space by computational means.}, ISSN = {1359-6446}, DOI = {10.1016/j.drudis.2016.07.001}, url = {http://www.sciencedirect.com/science/article/pii/S1359644616302513 https://pdf.sciencedirectassets.com/271275/1-s2.0-S1359644616X00128/1-s2.0-S1359644616302513/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIQDpMFAxqO8i5cWwO8J2bidQOOPWWOgX2xYgjlCqnmYpKAIgMz6zEqJOOqjcysWG%2F%2BjDZIPEG4hPysl42TQ%2BxrkJgLgq2gMIQRACGgwwNTkwMDM1NDY4NjUiDMbVMeQJp%2BA6xuTeeiq3A5yGUmiSxbecX6zyK9C0u9d8FvveGrkPLG2bgf%2FLpoQrYo2WyvA%2BBWqUubZ%2F%2F2lzFcSTpeDFbT3qjC0N3gXJAnlrhfnB4HtdM5JkFOs7rk4T5uxWa2QB%2Bxrb0uGWp6C%2FKniuq6eBMiJ59EW8Qua9SC1HjapOsfuus9g5HoQTBdya%2B%2B93vPUyT1l6n3DvNF79aTePLdf4GzCoc3La3CqQwXZ%2Bv00XVVkSLXyHqEtn%2BKj4RqGYDx5vybmCYgNtuQnt%2F4u%2FKij1yfRzcl%2BKOheRiB2UBQBFkx%2BGRL%2BqBFLx23kYZU2PrVD4ZjQMMXyglfn7R41W1Ts944jcTs7eKtPEaIuwbGZFi3rfxU%2BBL%2BrhXsqDJMbPTE%2BrqYpk6xiwMVJaY6kJH62kCLazVZrQ49cjhJjxeJti4aqVRxjr4XOP%2FJ9EatP%2BZoD3q47yNzrS1dG3FcQOp6Rtx1LGD9QPU8GrLpoB2%2F%2BrydWuCVqCFWw5iNbyp05sWQsfmSpFEMzsvkKO%2FCw0bATpkHdkF6WOn0A1lXIOsI0cDUPAe1xWJ3L0KZySQ0UZUqXJ8Gw4v%2FTlL5BY%2FUxSnor26xYwn6aO6wU6tAHBqopuW5pcz%2FJI%2BrCyUdYGVL8ZGUcN9osxZNHlsdHl%2FPSb5Ey3HqdiHTks1pszrFK8F0ZxsQNCYajkgKT3SAzhgrTmaNYfXyzLVkl3rMbW5QA0SqgsnR79JfHgUXuHGBnWyrsVF5mu9vmFjpTB4j2VqmtMOIjghMdHO%2FOIcR59ey2VTJQKE1Ulq0WJqECO72nl8nHMFEUoBLcWlCu5cwJlo5NxAcL7qC1hNPBzJlNFYMqU07s%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090752Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTY5J43SP76%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=41d5423206e9b4da9d8bad5f7023e4f96b18b2664c923fbc9de439a7f34293c4&hash=218a0f350491d1c5c383f9505b728b13f7879d7491bb1fb18a042fb95213e569&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S1359644616302513&tid=spdf-4c8cdfd3-7d8d-4705-a232-8bf4948ce6eb&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2016}, type = {Journal Article} }  x  More than a look into a crystal ball: protein structure elucidation guided by molecular dynamics simulations

The ‘form follows function’ principle implies that a structural determination of protein structures is indispensable to understand proteins in their biological roles. However, experimental methods still show shortcomings in the description of the dynamic properties of proteins. Therefore, molecular dynamics (MD) simulations represent an essential tool for structural biology to investigate proteins as flexible and dynamic entities. Here, we will give an overview on the impact of MD simulations on structural investigations, including studies that aim at a prediction of protein-folding pathways, protein-assembly processes and the sampling of conformational space by computational means.

[112]

A. Bock, M. Bermudez, F. Krebs, C. Matera, B. Chirinda, D. Sydow, C. Dallanoce, U. Holzgrabe, M. De Amici, M. J. Lohse, G. Wolber, and K. Mohr. Ligand Binding Ensembles Determine Graded Agonist Efficacies at a G Protein-Coupled Receptor, J Biol Chem, 291(31):16375-16389, 2016.
Links: [doi:10.1074/jbc.M116.735431] [show BibTeX] [show abstract]  x  @article{RN197, author = {Bock, Andreas and Bermudez, Marcel and Krebs, Fabian and Matera, Carlo and Chirinda, Brian and Sydow, Dominique and Dallanoce, Clelia and Holzgrabe, Ulrike and De Amici, Marco and Lohse, Martin J. and Wolber, Gerhard and Mohr, Klaus}, title = {Ligand Binding Ensembles Determine Graded Agonist Efficacies at a G Protein-Coupled Receptor}, journal = {Journal of Biological Chemistry}, volume = {291}, number = {31}, pages = {16375-16389}, abstract = {G protein-coupled receptors constitute the largest family of membrane receptors and modulate almost every physiological process in humans. Binding of agonists to G protein-coupled receptors induces a shift from inactive to active receptor conformations. Biophysical studies of the dynamic equilibrium of receptors suggest that a portion of receptors can remain in inactive states even in the presence of saturating concentrations of agonist and G protein mimetic. However, the molecular details of agonist-bound inactive receptors are poorly understood. Here we use the model of bitopic orthosteric/allosteric (i.e. dualsteric) agonists for muscarinic M2 receptors to demonstrate the existence and function of such inactive agonist·receptor complexes on a molecular level. Using all-atom molecular dynamics simulations, dynophores (i.e. a combination of static three-dimensional pharmacophores and molecular dynamics-based conformational sampling), ligand design, and receptor mutagenesis, we show that inactive agonist·receptor complexes can result from agonist binding to the allosteric vestibule alone, whereas the dualsteric binding mode produces active receptors. Each agonist forms a distinct ligand binding ensemble, and different agonist efficacies depend on the fraction of purely allosteric (i.e. inactive) versus dualsteric (i.e. active) binding modes. We propose that this concept may explain why agonist·receptor complexes can be inactive and that adopting multiple binding modes may be generalized also to small agonists where binding modes will be only subtly different and confined to only one binding site.}, keywords = {gpcr}, DOI = {10.1074/jbc.M116.735431}, url = {http://www.jbc.org/content/291/31/16375.abstract http://www.jbc.org/content/291/31/16375.full.pdf}, year = {2016}, type = {Journal Article} }  x  Ligand Binding Ensembles Determine Graded Agonist Efficacies at a G Protein-Coupled Receptor

G protein-coupled receptors constitute the largest family of membrane receptors and modulate almost every physiological process in humans. Binding of agonists to G protein-coupled receptors induces a shift from inactive to active receptor conformations. Biophysical studies of the dynamic equilibrium of receptors suggest that a portion of receptors can remain in inactive states even in the presence of saturating concentrations of agonist and G protein mimetic. However, the molecular details of agonist-bound inactive receptors are poorly understood. Here we use the model of bitopic orthosteric/allosteric (i.e. dualsteric) agonists for muscarinic M2 receptors to demonstrate the existence and function of such inactive agonist·receptor complexes on a molecular level. Using all-atom molecular dynamics simulations, dynophores (i.e. a combination of static three-dimensional pharmacophores and molecular dynamics-based conformational sampling), ligand design, and receptor mutagenesis, we show that inactive agonist·receptor complexes can result from agonist binding to the allosteric vestibule alone, whereas the dualsteric binding mode produces active receptors. Each agonist forms a distinct ligand binding ensemble, and different agonist efficacies depend on the fraction of purely allosteric (i.e. inactive) versus dualsteric (i.e. active) binding modes. We propose that this concept may explain why agonist·receptor complexes can be inactive and that adopting multiple binding modes may be generalized also to small agonists where binding modes will be only subtly different and confined to only one binding site.

[111]

S. Bock, M. S. Murgueitio, G. Wolber, and G. Weindl. Acute myeloid leukaemia-derived Langerhans-like cells enhance Th1 polarization upon TLR2 engagement, Pharmacol Res, 105:44-53, 2016.
Links: [doi:10.1016/j.phrs.2016.01.016] [show BibTeX] [show abstract]  x  @article{RN183, author = {Bock, Stephanie and Murgueitio, Manuela S. and Wolber, Gerhard and Weindl, Günther}, title = {Acute myeloid leukaemia-derived Langerhans-like cells enhance Th1 polarization upon TLR2 engagement}, journal = {Pharmacological Research}, volume = {105}, pages = {44-53}, abstract = {Langerhans cells (LCs) represent a highly specialized subset of epidermal dendritic cells (DCs), yet not fully understood in their function of balancing skin immunity. Here, we investigated in vitro generated Langerhans-like cells obtained from the human acute myeloid leukaemia cell line MUTZ-3 (MUTZ-LCs) to study TLR- and cytokine-dependent activation of epidermal DCs. MUTZ-LCs revealed high TLR2 expression and responded robustly to TLR2 engagement, confirmed by increased CD83, CD86, PD-L1 and IDO expression, upregulated IL-6, IL-12p40 and IL-23p19 mRNA levels IL-8 release. TLR2 activation reduced CCR6 and elevated CCR7 mRNA expression and induced migration of MUTZ-LCs towards CCL21. Similar results were obtained by stimulation with pro-inflammatory cytokines TNF-α and IL-1β whereas ligands of TLR3 and TLR4 failed to induce a fully mature phenotype. Despite limited cytokine gene expression and production for TLR2-activated MUTZ-LCs, co-culture with naive CD4+ T cells led to significantly increased IFN-γ and IL-22 levels indicating Th1 differentiation independent of IL-12. TLR2-mediated effects were blocked by the putative TLR2/1 antagonist CU-CPT22, however, no selectivity for either TLR2/1 or TLR2/6 was observed. Computer-aided docking studies confirmed non-selective binding of the TLR2 antagonist. Taken together, our results indicate a critical role for TLR2 signalling in MUTZ-LCs considering the leukemic origin of the generated Langerhans-like cells.}, keywords = {Acute myeloid leukaemia (AML) Langerhans cells Toll-like receptors (TLR) TLR2 Pro-inflammatory cytokines T helper type 1 (Th1) cells}, ISSN = {1043-6618}, DOI = {10.1016/j.phrs.2016.01.016}, url = {http://www.sciencedirect.com/science/article/pii/S1043661816000220}, year = {2016}, type = {Journal Article} }  x  Acute myeloid leukaemia-derived Langerhans-like cells enhance Th1 polarization upon TLR2 engagement

Langerhans cells (LCs) represent a highly specialized subset of epidermal dendritic cells (DCs), yet not fully understood in their function of balancing skin immunity. Here, we investigated in vitro generated Langerhans-like cells obtained from the human acute myeloid leukaemia cell line MUTZ-3 (MUTZ-LCs) to study TLR- and cytokine-dependent activation of epidermal DCs. MUTZ-LCs revealed high TLR2 expression and responded robustly to TLR2 engagement, confirmed by increased CD83, CD86, PD-L1 and IDO expression, upregulated IL-6, IL-12p40 and IL-23p19 mRNA levels IL-8 release. TLR2 activation reduced CCR6 and elevated CCR7 mRNA expression and induced migration of MUTZ-LCs towards CCL21. Similar results were obtained by stimulation with pro-inflammatory cytokines TNF-α and IL-1β whereas ligands of TLR3 and TLR4 failed to induce a fully mature phenotype. Despite limited cytokine gene expression and production for TLR2-activated MUTZ-LCs, co-culture with naive CD4+ T cells led to significantly increased IFN-γ and IL-22 levels indicating Th1 differentiation independent of IL-12. TLR2-mediated effects were blocked by the putative TLR2/1 antagonist CU-CPT22, however, no selectivity for either TLR2/1 or TLR2/6 was observed. Computer-aided docking studies confirmed non-selective binding of the TLR2 antagonist. Taken together, our results indicate a critical role for TLR2 signalling in MUTZ-LCs considering the leukemic origin of the generated Langerhans-like cells.

[110]

E. Guerrieri, M. Bermudez, G. Wolber, I. P. Berzetei-Gurske, H. Schmidhammer, and M. Spetea. Structural determinants of diphenethylamines for interaction with the κ opioid receptor: Synthesis, pharmacology and molecular modeling studies, Bioorg Med Chem Lett, 26(19):4769-4774, 2016.
Links: [doi:10.1016/j.bmcl.2016.08.031] [show BibTeX] [show abstract]  x  @article{RN191, author = {Guerrieri, Elena and Bermudez, Marcel and Wolber, Gerhard and Berzetei-Gurske, Ilona P. and Schmidhammer, Helmut and Spetea, Mariana}, title = {Structural determinants of diphenethylamines for interaction with the κ opioid receptor: Synthesis, pharmacology and molecular modeling studies}, journal = {Bioorganic & Medicinal Chemistry Letters}, volume = {26}, number = {19}, pages = {4769-4774}, abstract = {The κ opioid (KOP) receptor crystal structure in an inactive state offers nowadays a valuable platform for inquiry into receptor function. We describe the synthesis, pharmacological evaluation and docking calculations of KOP receptor ligands from the class of diphenethylamines using an active-like structure of the KOP receptor attained by molecular dynamics simulations. The structure–activity relationships derived from computational studies was in accordance with pharmacological activities of targeted diphenethylamines at the KOP receptor established by competition binding and G protein activation in vitro assays. Our analysis identified that agonist binding results in breaking of the Arg156-Thr273 hydrogen bond, which stabilizes the inactive receptor conformation, and a crucial hydrogen bond with His291 is formed. Compounds with a phenolic 4-hydroxy group do not form the hydrogen bond with His291, an important residue for KOP affinity and agonist activity. The size of the N-substituent hosted by the hydrophobic pocket formed by Val108, Ile316 and Tyr320 considerably influences binding and selectivity, with the n-alkyl size limit being five carbon atoms, while bulky substituents turn KOP agonists in antagonists. Thus, combination of experimental and molecular modeling strategies provides an initial framework for understanding the structural features of diphenethylamines that are essential to promote binding affinity and selectivity for the KOP receptor, and may be involved in transduction of the ligand binding event into molecular changes, ultimately leading to receptor activation.}, keywords = {κ opioid receptor Diphenethylamine Agonist Antagonist Partial agonist SAR Molecular dynamics gpcr}, ISSN = {0960-894X}, DOI = {10.1016/j.bmcl.2016.08.031}, url = {http://www.sciencedirect.com/science/article/pii/S0960894X16308526 https://pdf.sciencedirectassets.com/271398/1-s2.0-S0960894X16X00182/1-s2.0-S0960894X16308526/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJGMEQCIBSuXR284U5c9bmAJSN5zVw47n5M5VTNwrBmGQ8hLXVcAiAWIgoCDAYq%2BrLMnoeOj0gcwMsJ%2BK2%2F2vx37jlwfG9V%2FiraAwhBEAIaDDA1OTAwMzU0Njg2NSIMjEBFMn9jIE9t1XN2KrcDLe7GRG%2FXcw3WEgKV9YXbSGYcHYB2z7r%2B9eRerOT0zpE0wRSFgQ%2FOH9BXlp37MIlzoDaMcVajFKZS8gcJXSICZZRdMHztkVCBW4DNZa%2BJxOwJ1E6Q6vzyyBGsc%2FRoV6Xba79A94ndoN8bYy6WNuplWyrl3mWsK2vv7sI6kqAQYvwZAuSo66P%2FLefOdgACsLXUvDUtMMpSN8TmoE6MAFh%2Fj9u1tN2PHd7Si9U0lR%2BPybWjyQIZhRLaPFiPA459dq%2F0DJYDW6PUXjnBlCqj2pjkDd8G%2FcrPGVCvjIs1dEukqNYRPh9wSQFFAb5Fi0wZV3zG%2F46Hc%2FeUQIprBOrsYtxFvQ1UWxSkaVfuuRD2NfJJC%2FoyWTyuxNmD0bdhukh9A21%2B1W83wJfu%2FecDVcxhN9MqXTDLroqrvl%2BRxWFnb%2BWbs%2B%2FV9bgL2cBI6AFt4X60UAEM%2FPSuYh%2FCMbaK1dtKiQLD4N%2F7kxQrpF%2BWzb6z4YOF5hW%2F4Jm%2BgH%2B0v9v9lego%2FcMGf98VdcRdShnMV0057mzmxPdKDL4AivAyKRRfnHrHbLoO1SdPlc41DKXR%2BjK0GtocjZ5j4aUAxDDnpo7rBTq1AThXMgqWLXhCysjiDb69KUDsmtirRuTrXpezLGPDfxkFp5ofIqWUR9J0yQNBLS%2BqlghqmfiGup4DJm90ED%2Bjr269Tuc2Ri4J0zfr7%2BcI1xixL%2Fy0rAQI30TJNbf1CsDGxfVixVDBG1Fkwa3KlpjjfAGAuGKaiPkPOMJuLo8YTbs28PVbbZSstkpcNX0npq661wJ6SM3c0BNDLzt2HCCzsKCoWT8MzDtnFnmY8Er2Z7ayg87lxx0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090730Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYZNRZYJFV%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=037fa3ee2555131e64b8b5688e7e4a686e30cbef207e6458fb55f96764b245fb&hash=08167983ee3f84a7da97f9261f1c7a8c6d2025de5b3aa82b896df1eb7cd149b2&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0960894X16308526&tid=spdf-8f3d8366-6e13-4767-a6f4-96592d64c57f&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2016}, type = {Journal Article} }  x  Structural determinants of diphenethylamines for interaction with the κ opioid receptor: Synthesis, pharmacology and molecular modeling studies

The κ opioid (KOP) receptor crystal structure in an inactive state offers nowadays a valuable platform for inquiry into receptor function. We describe the synthesis, pharmacological evaluation and docking calculations of KOP receptor ligands from the class of diphenethylamines using an active-like structure of the KOP receptor attained by molecular dynamics simulations. The structure–activity relationships derived from computational studies was in accordance with pharmacological activities of targeted diphenethylamines at the KOP receptor established by competition binding and G protein activation in vitro assays. Our analysis identified that agonist binding results in breaking of the Arg156-Thr273 hydrogen bond, which stabilizes the inactive receptor conformation, and a crucial hydrogen bond with His291 is formed. Compounds with a phenolic 4-hydroxy group do not form the hydrogen bond with His291, an important residue for KOP affinity and agonist activity. The size of the N-substituent hosted by the hydrophobic pocket formed by Val108, Ile316 and Tyr320 considerably influences binding and selectivity, with the n-alkyl size limit being five carbon atoms, while bulky substituents turn KOP agonists in antagonists. Thus, combination of experimental and molecular modeling strategies provides an initial framework for understanding the structural features of diphenethylamines that are essential to promote binding affinity and selectivity for the KOP receptor, and may be involved in transduction of the ligand binding event into molecular changes, ultimately leading to receptor activation.

[109]

J. R. Homoki, A. Nemes, E. Fazekas, G. Gyémánt, P. Balogh, F. Gál, J. Al-Asri, J. Mortier, G. Wolber, L. Babinszky, and J. Remenyik. Anthocyanin composition, antioxidant efficiency, and α-amylase inhibitor activity of different Hungarian sour cherry varieties (Prunus cerasus L.), Food Chem, 194:222-229, 2016.
Links: [doi:10.1016/j.foodchem.2015.07.130] [show BibTeX] [show abstract]  x  @article{RN177, author = {Homoki, Judit R. and Nemes, Andrea and Fazekas, Erika and Gyémánt, Gyöngyi and Balogh, Péter and Gál, Ferenc and Al-Asri, Jamil and Mortier, Jérémie and Wolber, Gerhard and Babinszky, László and Remenyik, Judit}, title = {Anthocyanin composition, antioxidant efficiency, and α-amylase inhibitor activity of different Hungarian sour cherry varieties (Prunus cerasus L.)}, journal = {Food Chemistry}, volume = {194}, pages = {222-229}, abstract = {Five Hungarian sour cherry cultivars were studied to determine their anthocyanin contents and their possible inhibitory properties. The water and methanol soluble antioxidant capacities were separately assessed by photoluminescence showing values ranged from 3.4 μg mg−1 to 15.4 μg mg−1, respectively. The “VN1” variety (selected from “Csengődi csokros”) showed the highest antioxidant capacity. The anthocyanin content, measured by pH differential method or isolated by solid phase extraction, was the highest also in “VN1”. Correlation was found between the anthocyanin content and the high antioxidant capacity. The main anthocyanin components were cyanidin-3-O-rutinoside and cyanidin-3-O-glucoside. The presence of malvidin-3,5-O-diglycoside was verified by MALDI-TOF MS. Sour cherry extracts and selected anthocyanins inhibited the human salivary alpha-amylase catalyzed hydrolysis competitively. The lowest IC50 value, 55 μg mL−1 or 80 μM, was measured for malvidin-3,5-O-diglycoside, for which possible binding modes within the alpha-amylase active site could be investigated in silico using molecular docking and molecular dynamics.}, keywords = {Sour cherry Antioxidants Anthocyanins Human salivary α-amylase Inhibition}, ISSN = {0308-8146}, DOI = {10.1016/j.foodchem.2015.07.130}, url = {http://www.sciencedirect.com/science/article/pii/S0308814615011644 http://ac.els-cdn.com/S0308814615011644/1-s2.0-S0308814615011644-main.pdf?_tid= 626cf250-a00c-11e5-9e98-00000aacb35d&acdnat=1449841255_9edc44dca9e7c73085280f5fd716d846}, year = {2016}, type = {Journal Article} }  x  Anthocyanin composition, antioxidant efficiency, and α-amylase inhibitor activity of different Hungarian sour cherry varieties (Prunus cerasus L.)

Five Hungarian sour cherry cultivars were studied to determine their anthocyanin contents and their possible inhibitory properties. The water and methanol soluble antioxidant capacities were separately assessed by photoluminescence showing values ranged from 3.4 μg mg−1 to 15.4 μg mg−1, respectively. The “VN1” variety (selected from “Csengődi csokros”) showed the highest antioxidant capacity. The anthocyanin content, measured by pH differential method or isolated by solid phase extraction, was the highest also in “VN1”. Correlation was found between the anthocyanin content and the high antioxidant capacity. The main anthocyanin components were cyanidin-3-O-rutinoside and cyanidin-3-O-glucoside. The presence of malvidin-3,5-O-diglycoside was verified by MALDI-TOF MS. Sour cherry extracts and selected anthocyanins inhibited the human salivary alpha-amylase catalyzed hydrolysis competitively. The lowest IC50 value, 55 μg mL−1 or 80 μM, was measured for malvidin-3,5-O-diglycoside, for which possible binding modes within the alpha-amylase active site could be investigated in silico using molecular docking and molecular dynamics.

[108]

S. Köhling, G. Künze, K. Lemmnitzer, M. Bermudez, G. Wolber, J. Schiller, D. Huster, and J. Rademann. Chemoenzymatic synthesis of nonasulfated tetrahyaluronan with a paramagnetic tag for studying its complex with Interleukin-10, Chemistry - A European Journal, 22(16): 5563-5574, 2016.
Links: [doi:10.1002/chem.201504459] [show BibTeX] [show abstract]  x  @article{RN184, author = {Köhling, Sebastian and Künze, Georg and Lemmnitzer, Katharina and Bermudez, Marcel and Wolber, Gerhard and Schiller, Jürgen and Huster, Daniel and Rademann, Jörg}, title = {Chemoenzymatic synthesis of nonasulfated tetrahyaluronan with a paramagnetic tag for studying its complex with Interleukin-10}, journal = {Chemistry - A European Journal}, volume = {22}, number = {16}, pages = { 5563-5574}, abstract = {Implants and artificial biomaterials containing sulfated hyaluronans have been shown to improve the healing of injured skin and bones. It is hypothesized that these effects are mediated by the binding of sulfated glycosaminoglycans (GAGs) to growth factors and cytokines, resulting in the sequestering of proteins to the wound healing site and in modulated protein activity. Given that no direct synthetic access to sulfated oligohyaluronans has been available, little is known about their protein binding and the structure of the resulting protein complexes. Here, the chemoenzymatic preparation of oligohyaluronans on the gram scale is described. Oligohyaluronans are converted into anomeric azides at the reducing end, enabling the attachment of analytical labels through an anomeric ligation reaction. A nonasulfated tetrahyaluronan–ethylenediaminetetraacetic acid derivative has been produced and used as a paramagnetic tag for the elucidation of the complex of this ligand with interleukin-10 using paramagnetic relaxation enhancement NMR analysis. The metal ion position is resolved with 1.0 Å, enabling a refined structural model of the complex.}, keywords = {carbohydrates cytokines growth factors host–guest systems protein structures}, ISSN = {1521-3765}, DOI = {10.1002/chem.201504459}, url = {http://dx.doi.org/10.1002/chem.201504459 http://onlinelibrary.wiley.com/store/10.1002/chem.201504459/asset/chem201504459.pdf?v= 1&t=ili6eox1&s=58b1d54b76bcf28cf8559dcb069e2abdebc61887}, year = {2016}, type = {Journal Article} }  x  Chemoenzymatic synthesis of nonasulfated tetrahyaluronan with a paramagnetic tag for studying its complex with Interleukin-10

Implants and artificial biomaterials containing sulfated hyaluronans have been shown to improve the healing of injured skin and bones. It is hypothesized that these effects are mediated by the binding of sulfated glycosaminoglycans (GAGs) to growth factors and cytokines, resulting in the sequestering of proteins to the wound healing site and in modulated protein activity. Given that no direct synthetic access to sulfated oligohyaluronans has been available, little is known about their protein binding and the structure of the resulting protein complexes. Here, the chemoenzymatic preparation of oligohyaluronans on the gram scale is described. Oligohyaluronans are converted into anomeric azides at the reducing end, enabling the attachment of analytical labels through an anomeric ligation reaction. A nonasulfated tetrahyaluronan–ethylenediaminetetraacetic acid derivative has been produced and used as a paramagnetic tag for the elucidation of the complex of this ligand with interleukin-10 using paramagnetic relaxation enhancement NMR analysis. The metal ion position is resolved with 1.0 Å, enabling a refined structural model of the complex.

[107]

B. Nizami, D. Sydow, G. Wolber, and B. Honarparvar. Molecular insight on the binding of NNRTI to K103N mutated HIV-1 RT: molecular dynamics simulations and dynamic pharmacophore analysis, Mol Biosyst, 12:3385-3395, 2016.
Links: [doi:10.1039/C6MB00428H] [show BibTeX]  x  @article{RN196, author = {Nizami, Bilal and Sydow, Dominique and Wolber, Gerhard and Honarparvar, Bahareh}, title = {Molecular insight on the binding of NNRTI to K103N mutated HIV-1 RT: molecular dynamics simulations and dynamic pharmacophore analysis}, journal = {Molecular BioSystems}, volume = {12}, pages = {3385-3395}, DOI = {10.1039/C6MB00428H}, url = {https://pubs.rsc.org/en/content/articlepdf/2016/mb/c6mb00428h}, year = {2016}, type = {Journal Article} }

[106]

V. Obermoser, M. E. Urban, M. S. Murgueitio, G. Wolber, U. Kintscher, and R. Gust. New telmisartan-derived PPARγ agonists: Impact of the 3D-binding mode on the pharmacological profile, Eur J Med Chem, 124:138-152, 2016.
Links: [doi:10.1016/j.ejmech.2016.08.027] [show BibTeX] [show abstract]  x  @article{RN194, author = {Obermoser, Victoria and Urban, Margarethe E. and Murgueitio, Manuela S. and Wolber, Gerhard and Kintscher, Ulrich and Gust, Ronald}, title = {New telmisartan-derived PPARγ agonists: Impact of the 3D-binding mode on the pharmacological profile}, journal = {European Journal of Medicinal Chemistry}, volume = {124}, pages = {138-152}, abstract = {In previous studies, the 4′-((2-propyl-1H-benzo[d]imidazol-1-yl)methyl)-[1,1′-biphenyl]-2-carboxylic acid was identified as pharmacophoric core for PPARγ activation. In this structure-activity relationship study the C2-alkyl chain was elongated and the 2-COOH group was changed to a carbamide/nitrile or shifted to the 3- or 4-position. Furthermore, the benzo[d]imidazole was exchanged by 2,3-dihydrobenzo[d]thiazole or 1H-indole. C2-propyl derivatives showed the profile of partial agonists, while elongation of the C2-chain to that of an n-heptyl group or a 4-COOH shift changed the pharmacological profile to that of a potent full agonist. This finding can be explained by binding to the LBD in different ligand conformations. Two anchoring points (Tyr473 and Arg288) exist in the LBD, which have to be contacted to achieve receptor activation. In a crystal violet chemosensitivity assay using COS-7 cells and LNCaP cells expressing PPARγ only the carboxamide derivatives influenced the cell growth, independently on the presence of the PPARγ. Therefore, receptor mediated cytotoxicity can be excluded.}, keywords = {PPARγ Transactivation Cytotoxicity Binding mode Molecular modeling}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2016.08.027}, url = {http://www.sciencedirect.com/science/article/pii/S0223523416306705 https://pdf.sciencedirectassets.com/271932/1-s2.0-S0223523416X00165/1-s2.0-S0223523416306705/main.pdf?X-Amz-Security-Token= AgoJb3JpZ2luX2VjEJn%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCXVzLWVhc3QtMSJHMEUCIBfvzJJhZ1Mm5mwy0J3B5VMuELdFjoz7sIRqN8wYSzx3AiEA5SeL7MgEjFO0B9r5FrlpUN4T0hArwMRoS5vGU9JFDzkq2gMIQhACGgwwNTkwMDM1NDY4NjUiDBOT17U1MUqycs1%2FKCq3AxGHFD6W1QLBSzH%2FhBU3v8JJteKuM%2BMlhBDgx9HJr06UFb8BZd%2BHmmbs1ur5t%2FlqtRCT5APQ%2Fzl6M%2FIM8%2F6YwmMYXt9Jyw268%2FtZeBsyIAjhb9UY49j0c7v6aVzNad%2FGYTpVso5RHp%2FRIuM5L67h7pTwnakyTSI6BnpaJqI2B9kWP4JEsZprxWxTmvQw9wKd%2BZ%2Fa4mZjyJSBse7DFly8%2FGnCKXIXFbkL7gEHIAamV19AyDb7zMu0NjKSYkVhnMKdyKtcoydss0kNGXNm7HiEVwqeBYZLCKy4Gr96z9kBNqkcZ%2BCvqAOmMj10aPUlpkLbmx197FcTVJ8VImn9RLlCJRDmDXNX5yS0%2B73PI%2BEazQ5%2BwF1N29hqIzLnT1Cc5utmeZ0G5AMefCBRfmgg6E2TbmfR7Ww0V5jCzNNuAslQXXlpfPN3WJ9keKLw21X%2BSCqBPm%2Fu6Xis2DUor4OC8wohPM2ZjGByx3Gqx2LFJIPCZN3cJyL1gxaivo%2BET3s3jVm6OY0z8nVa20tLJ7Fw2PK6UzrCG3VQ%2F1Wx6deq5BIg0CjfaQgBifcwYqv%2F%2F9ZMxV6ugcNNvcoHxYgw6rmO6wU6tAGkBGWe9a6585563qyrPRyFqAu%2FM2418LDCloFTRDRH9weZ%2BgHQW1B1m%2F%2FVbRWsTdBwvnU%2BOX7Dk7jsNsnZIzAffqBskxE32pvB9%2BEG%2Fi%2F0HR72BRBiQS0zSE42%2F3v4dfwbryhRJ%2FbSj6%2BtUzOYJwiXE%2BTFI6%2Bw6by7InD6OwR0E1IdegTjGtbvA15LPpug9CTJY%2FTVHEISFL2jcir2FrGkZbfPHhgSZLoAg3rn1UL%2Buq%2FcLM4%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190826T090924Z&X-Amz-SignedHeaders=host&X-Amz-Expires=300&X-Amz-Credential=ASIAQ3PHCVTYRDRFHOHF%2F20190826%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=d2af90fb06808e3b0bac76b9342ee55dc05a1918c4bf6356770302f3be9ca63a&hash=3712ce5d2ed3cc4cfea7455155afedf7877f1ff08f9c2449aca8649d1b47fa34&host=68042c943591013ac2b2430a89b270f6af2c76d8dfd086a07176afe7c76c2c61&pii=S0223523416306705&tid=spdf-de97841d-cbf2-4767-9ef3-8519019df2d9&sid=2685c81b50af534a6f99d1c429305bd4118dgxrqb&type=client}, year = {2016}, type = {Journal Article} }  x  New telmisartan-derived PPARγ agonists: Impact of the 3D-binding mode on the pharmacological profile

In previous studies, the 4′-((2-propyl-1H-benzo[d]imidazol-1-yl)methyl)-[1,1′-biphenyl]-2-carboxylic acid was identified as pharmacophoric core for PPARγ activation. In this structure-activity relationship study the C2-alkyl chain was elongated and the 2-COOH group was changed to a carbamide/nitrile or shifted to the 3- or 4-position. Furthermore, the benzo[d]imidazole was exchanged by 2,3-dihydrobenzo[d]thiazole or 1H-indole. C2-propyl derivatives showed the profile of partial agonists, while elongation of the C2-chain to that of an n-heptyl group or a 4-COOH shift changed the pharmacological profile to that of a potent full agonist. This finding can be explained by binding to the LBD in different ligand conformations. Two anchoring points (Tyr473 and Arg288) exist in the LBD, which have to be contacted to achieve receptor activation. In a crystal violet chemosensitivity assay using COS-7 cells and LNCaP cells expressing PPARγ only the carboxamide derivatives influenced the cell growth, independently on the presence of the PPARγ. Therefore, receptor mediated cytotoxicity can be excluded.

[105]

C. Rakers, F. Schumacher, W. Meinl, H. Glatt, B. Kleuser, and G. Wolber. In silico prediction of human sulfotransferase 1E1 activity guided by pharmacophores from molecular dynamics simulations, J Biol Chem, 291(1):58-71, 2016.
Links: [doi:10.1074/jbc.M115.685610] [show BibTeX] [show abstract]  x  @article{RN180, author = {Rakers, Christin and Schumacher, Fabian and Meinl, Walter and Glatt, Hansruedi and Kleuser, Burkhard and Wolber, Gerhard}, title = {In silico prediction of human sulfotransferase 1E1 activity guided by pharmacophores from molecular dynamics simulations}, journal = {Journal of Biological Chemistry}, volume = {291}, number = {1}, pages = {58-71}, abstract = {Acting during phase II metabolism, sulfotransferases (SULTs) serve detoxification by transforming a broad spectrum of compounds from pharmaceutical, nutritional, or environmental sources into more easily excretable metabolites. However, SULT activity has also been shown to promote formation of reactive metabolites that may have genotoxic effects. SULT subtype 1E1 (SULT1E1) was identified as a key player in estrogen homeostasis, which is involved in many physiological processes and the pathogenesis of breast and endometrial cancer. The development of an in silico prediction model for SULT1E1 ligands would therefore support the development of metabolically inert drugs and help to assess health risks related to hormonal imbalances. Here, we report on a novel approach to develop a model that enables prediction of substrates and inhibitors of SULT1E1. Molecular dynamics simulations were performed to investigate enzyme flexibility and sample protein conformations. Pharmacophores were developed that served as a cornerstone of the model and machine learning techniques were applied for prediction refinement. The prediction model was used to screen the DrugBank (a database of experimental and approved drugs): 28 % of the predicted hits were reported in literature as ligands of SULT1E1. From the remaining hits, a selection of nine molecules was subjected to biochemical assay validation and experimental results were in accordance with the in silico prediction of SULT1E1 inhibitors and substrates, thus affirming our prediction hypotheses.}, DOI = {10.1074/jbc.M115.685610}, url = {http://www.jbc.org/content/early/2015/11/05/jbc.M115.685610.abstract http://www.jbc.org/content/early/2015/11/05/jbc.M115.685610.full.pdf}, year = {2016}, type = {Journal Article} }  x  In silico prediction of human sulfotransferase 1E1 activity guided by pharmacophores from molecular dynamics simulations

Acting during phase II metabolism, sulfotransferases (SULTs) serve detoxification by transforming a broad spectrum of compounds from pharmaceutical, nutritional, or environmental sources into more easily excretable metabolites. However, SULT activity has also been shown to promote formation of reactive metabolites that may have genotoxic effects. SULT subtype 1E1 (SULT1E1) was identified as a key player in estrogen homeostasis, which is involved in many physiological processes and the pathogenesis of breast and endometrial cancer. The development of an in silico prediction model for SULT1E1 ligands would therefore support the development of metabolically inert drugs and help to assess health risks related to hormonal imbalances. Here, we report on a novel approach to develop a model that enables prediction of substrates and inhibitors of SULT1E1. Molecular dynamics simulations were performed to investigate enzyme flexibility and sample protein conformations. Pharmacophores were developed that served as a cornerstone of the model and machine learning techniques were applied for prediction refinement. The prediction model was used to screen the DrugBank (a database of experimental and approved drugs): 28 % of the predicted hits were reported in literature as ligands of SULT1E1. From the remaining hits, a selection of nine molecules was subjected to biochemical assay validation and experimental results were in accordance with the in silico prediction of SULT1E1 inhibitors and substrates, thus affirming our prediction hypotheses.

[104]

J. Al-Asri, E. Fazekas, G. Lehoczki, A. Perdih, C. Görick, M. F. Melzig, G. Gyémánt, G. Wolber, and J. Mortier. From carbohydrates to drug-like fragments: Rational development of novel α-amylase inhibitors, Bioorg Med Chem, 23(20):6725-6732, 2015.
Links: [doi:10.1016/j.bmc.2015.09.007] [show BibTeX] [show abstract]  x  @article{RN181, author = {Al-Asri, Jamil and Fazekas, Erika and Lehoczki, Gábor and Perdih, Andrej and Görick, Cornelia and Melzig, Matthias F. and Gyémánt, Gyöngyi and Wolber, Gerhard and Mortier, Jérémie}, title = {From carbohydrates to drug-like fragments: Rational development of novel α-amylase inhibitors}, journal = {Bioorganic & Medicinal Chemistry}, volume = {23}, number = {20}, pages = {6725-6732}, abstract = {Starch catabolism leading to high glucose level in blood is highly problematic in chronic metabolic diseases, such as type II diabetes and obesity. α-Amylase catalyzes the hydrolysis of starch, increasing blood sugar concentration. Its inhibition represents a promising therapeutic approach to control hyperglycaemia. However, only few drug-like molecule inhibitors without sugar moieties have been discovered so far, and little information on the enzymatic mechanism is available. This work aims at the discovery of novel small α-amylase binders using a systematic in silico methodology. 3D-pharmacophore-based high throughput virtual screening of small compounds libraries was performed to identify compounds with high α-amylase affinity. Twenty-seven compounds were selected and biologically tested, revealing IC50 values in the micromolar range and ligand efficiency higher than the one of the bound form of acarbose, which is used as a reference for α-amylase inhibition.}, keywords = {α-Amylase inhibition Fragment-based drug design Virtual screening Pharmacophore model Hyperglycaemia Obesity Type II diabetes}, ISSN = {0968-0896}, DOI = {10.1016/j.bmc.2015.09.007}, url = {http://www.sciencedirect.com/science/article/pii/S0968089615300304 http://ac.els-cdn.com/S0968089615300304/1-s2.0-S0968089615300304-main.pdf?_tid= 975ce9ee-a00b-11e5-8116-00000aab0f6b&acdnat=1449840915_65cd6dd9bfdd7bab4bc7170cedef1f08}, year = {2015}, type = {Journal Article} }  x  From carbohydrates to drug-like fragments: Rational development of novel α-amylase inhibitors

Starch catabolism leading to high glucose level in blood is highly problematic in chronic metabolic diseases, such as type II diabetes and obesity. α-Amylase catalyzes the hydrolysis of starch, increasing blood sugar concentration. Its inhibition represents a promising therapeutic approach to control hyperglycaemia. However, only few drug-like molecule inhibitors without sugar moieties have been discovered so far, and little information on the enzymatic mechanism is available. This work aims at the discovery of novel small α-amylase binders using a systematic in silico methodology. 3D-pharmacophore-based high throughput virtual screening of small compounds libraries was performed to identify compounds with high α-amylase affinity. Twenty-seven compounds were selected and biologically tested, revealing IC50 values in the micromolar range and ligand efficiency higher than the one of the bound form of acarbose, which is used as a reference for α-amylase inhibition.

[103]

M. Bermudez, C. Rakers, and G. Wolber. Structural characteristics of the allosteric binding site represent a key to subtype selective modulators of muscarinic acetylcholine receptors, Mol Inf, 34(8):526-530, 2015.
Links: [doi:10.1002/minf.201500025] [show BibTeX] [show abstract]  x  @article{RN178, author = {Bermudez, Marcel and Rakers, Christin and Wolber, Gerhard}, title = {Structural characteristics of the allosteric binding site represent a key to subtype selective modulators of muscarinic acetylcholine receptors}, journal = {Molecular Informatics}, volume = {34}, number = {8}, pages = {526-530}, abstract = {The high conservation of the orthosteric acetylcholine binding site of muscarinic receptors (MAChR) represents a considerable challenge in terms of designing subtype selective drugs. A promising approach to gain subtype selectivity is to include allosteric or dualsteric targeting that aims to address more specific extracellular binding sites. Despite recent advances in crystallography of G protein coupled receptors (GPCRs), structural information for all 5 MAChR subtypes is not yet available. Here we report structural models of the active and the inactive receptor state of all subtypes derived by homology modelling in combination with MD simulations. The comparison of the allosteric binding site unveils the characteristics for each subtype on a structural level and indicates anchor points for rational design of selective drugs. Additionally, homology models offer the possibility for a rational explanation of dualsteric subtype selectivity, as we show for the M2 over M5 selectivity of the dualsteric ligands Atr-6-naph and Iper-6-phth.}, keywords = {Drug design Medicinal chemistry Molecular dynamics Protein models Receptors gpcr}, ISSN = {1868-1751}, DOI = {10.1002/minf.201500025}, url = {http://dx.doi.org/10.1002/minf.201500025 http://onlinelibrary.wiley.com/store/10.1002/minf.201500025/asset/526_ftp.pdf?v= 1&t=ii1pqq6x&s=d5a558605b40783fdaa53e4c2a054424c9266926}, year = {2015}, type = {Journal Article} }  x  Structural characteristics of the allosteric binding site represent a key to subtype selective modulators of muscarinic acetylcholine receptors

The high conservation of the orthosteric acetylcholine binding site of muscarinic receptors (MAChR) represents a considerable challenge in terms of designing subtype selective drugs. A promising approach to gain subtype selectivity is to include allosteric or dualsteric targeting that aims to address more specific extracellular binding sites. Despite recent advances in crystallography of G protein coupled receptors (GPCRs), structural information for all 5 MAChR subtypes is not yet available. Here we report structural models of the active and the inactive receptor state of all subtypes derived by homology modelling in combination with MD simulations. The comparison of the allosteric binding site unveils the characteristics for each subtype on a structural level and indicates anchor points for rational design of selective drugs. Additionally, homology models offer the possibility for a rational explanation of dualsteric subtype selectivity, as we show for the M2 over M5 selectivity of the dualsteric ligands Atr-6-naph and Iper-6-phth.

[102]

M. Bermudez, and G. Wolber. Structure vs. function - the impact of computational methods on the discovery of specific GPCR-ligands, Bioorg Med Chem, 23(14):3907-3912, 2015.
Links: [doi:10.1016/j.bmc.2015.03.026] [show BibTeX] [show abstract]  x  @article{RN171, author = {Bermudez, Marcel and Wolber, G.}, title = {Structure vs. function - the impact of computational methods on the discovery of specific GPCR-ligands}, journal = {Bioorganic & Medicinal Chemistry}, volume = {23}, number = {14}, pages = {3907-3912}, abstract = {Over the past decades, computational methods have become invaluable for drug design campaigns but also as auxiliary tool for structural biology. The combination of experimental and in silico methods in the field of G protein coupled receptors (GPCRs) is indispensable. Despite recent groundbreaking achievements in GPCR crystallography, structural information for the vast majority of this physiologically important protein class is only accessible through homology models. Since the understanding of the conformational changes resulting in multiple activation pathways is incomplete, the design of specific GPCR modulating drugs remains a major challenge. However, due to the highly interdisciplinary requirements for the investigation of receptor function and the necessity of joining scientist from different fields, computational approaches gain importance in rationalizing and illustrating certain specific effects. In silico methods, such as molecular dynamics (MD) simulations, pharmacophore modeling or docking, proved to be suitable to complement experimental approaches. In this review, we highlight recent examples of in silico studies that were successfully applied in the field of GPCR research. Those approaches follow two main goals: Firstly, structural investigations that help to understand the receptor function and the characterization of ligand binding and secondly the identification of novel GPCR modulators as potential drugs.}, keywords = {gpcr}, DOI = {10.1016/j.bmc.2015.03.026}, url = {http://ac.els-cdn.com/S0968089615002102/1-s2.0-S0968089615002102-main.pdf?_tid=94b05366-a00b-11e5-866f-00000aacb35f&acdnat=1449840910_d9e103adde14b947c8c62833dffbd577}, year = {2015}, type = {Journal Article} }  x  Structure vs. function - the impact of computational methods on the discovery of specific GPCR-ligands

Over the past decades, computational methods have become invaluable for drug design campaigns but also as auxiliary tool for structural biology. The combination of experimental and in silico methods in the field of G protein coupled receptors (GPCRs) is indispensable. Despite recent groundbreaking achievements in GPCR crystallography, structural information for the vast majority of this physiologically important protein class is only accessible through homology models. Since the understanding of the conformational changes resulting in multiple activation pathways is incomplete, the design of specific GPCR modulating drugs remains a major challenge. However, due to the highly interdisciplinary requirements for the investigation of receptor function and the necessity of joining scientist from different fields, computational approaches gain importance in rationalizing and illustrating certain specific effects. In silico methods, such as molecular dynamics (MD) simulations, pharmacophore modeling or docking, proved to be suitable to complement experimental approaches. In this review, we highlight recent examples of in silico studies that were successfully applied in the field of GPCR research. Those approaches follow two main goals: Firstly, structural investigations that help to understand the receptor function and the characterization of ligand binding and secondly the identification of novel GPCR modulators as potential drugs.

[101]

R. B. El-Houri, D. E. Kotowska, K. B. Christensen, S. Bhattacharya, N. Oksbjerg, G. Wolber, K. Kristiansen, and L. P. Christensen. Polyacetylenes from carrots (Daucus carota) improve glucose uptake in vitro in adipocytes and myotubes, Food & Function, 6(7):2135-44, 2015.
Links: [doi:10.1039/C5FO00223K] [show BibTeX] [show abstract]  x  @article{RN175, author = {El-Houri, Rime Bahij and Kotowska, Dorota Ewa and Christensen, Kathrine Bisgaard and Bhattacharya, Sumangala and Oksbjerg, Niels and Wolber, Gerhard and Kristiansen, Karsten and Christensen, Lars Porskjær}, title = {Polyacetylenes from carrots (Daucus carota) improve glucose uptake in vitro in adipocytes and myotubes}, journal = {Food & Function}, volume = {6}, number = {7}, pages = {2135-44}, abstract = {A dichloromethane (DCM) extract of carrot roots was found to stimulate insulin-dependent glucose uptake (GU) in adipocytes in a dose dependent manner. Bioassay-guided fractionation of the DCM extract resulted in the isolation of the polyacetylenes falcarinol and falcarindiol. Both polyacetylenes were able to significantly stimulate basal and/or insulin-dependent GU in 3T3-L1 adipocytes and porcine myotube cell cultures in a dose-dependent manner. Falcarindiol increased peroxisome proliferator-activated receptor (PPAR)γ-mediated transactivation significantly at concentrations of 3, 10 and 30 μM, while PPARγ-mediated transactivation by falcarinol was only observed at 10 μM. Docking studies accordingly indicated that falcarindiol binds to the ligand binding domain of PPARγ with higher affinity than falcarinol and that both polyacetylenes exhibit characteristics of PPARγ partial agonists. Falcarinol was shown to inhibit adipocyte differentiation as evident by gene expression studies and Oil Red O staining, whereas falcarindiol did not inhibit adipocyte differentiation, which indicates that these polyacetylenes have distinct modes of action. The results of the present study suggest that falcarinol and falcarindiol may represent scaffolds for novel partial PPARγ agonists with possible antidiabetic properties.}, DOI = {10.1039/C5FO00223K}, url = {http://pubs.rsc.org/en/content/articlepdf/2015/fo/c5fo00223k}, year = {2015}, type = {Journal Article} }  x  Polyacetylenes from carrots (Daucus carota) improve glucose uptake in vitro in adipocytes and myotubes

A dichloromethane (DCM) extract of carrot roots was found to stimulate insulin-dependent glucose uptake (GU) in adipocytes in a dose dependent manner. Bioassay-guided fractionation of the DCM extract resulted in the isolation of the polyacetylenes falcarinol and falcarindiol. Both polyacetylenes were able to significantly stimulate basal and/or insulin-dependent GU in 3T3-L1 adipocytes and porcine myotube cell cultures in a dose-dependent manner. Falcarindiol increased peroxisome proliferator-activated receptor (PPAR)γ-mediated transactivation significantly at concentrations of 3, 10 and 30 μM, while PPARγ-mediated transactivation by falcarinol was only observed at 10 μM. Docking studies accordingly indicated that falcarindiol binds to the ligand binding domain of PPARγ with higher affinity than falcarinol and that both polyacetylenes exhibit characteristics of PPARγ partial agonists. Falcarinol was shown to inhibit adipocyte differentiation as evident by gene expression studies and Oil Red O staining, whereas falcarindiol did not inhibit adipocyte differentiation, which indicates that these polyacetylenes have distinct modes of action. The results of the present study suggest that falcarinol and falcarindiol may represent scaffolds for novel partial PPARγ agonists with possible antidiabetic properties.

[100]

R. B. El-Houri, J. Mortier, M. S. Murgueitio, G. Wolber, and L. P. Christensen. Identification of PPARγ Agonists from Natural Sources Using Different In Silico Approaches, Planta Med, 81(06):488-494, 2015.
Links: [doi:10.1055/s-0034-1383119] [show BibTeX] [show abstract]  x  @article{RN151, author = {El-Houri, Rime B. and Mortier, Jérémie and Murgueitio, Manuela S. and Wolber, Gerhard and Christensen, Lars P.}, title = {Identification of PPARγ Agonists from Natural Sources Using Different In Silico Approaches}, journal = {Planta Medica}, volume = {81}, number = {06}, pages = {488-494}, abstract = {Peroxisome proliferator-activated receptor γ plays an important role in lipid and glucose homeostasis and is the target of many drug discovery investigations because of its role in diseases such as type 2 diabetes. Activation of peroxisome proliferator-activated receptor γ by agonists leads to a conformational change in the ligand-binding domain altering the transcription of several target genes involved in glucose and lipid metabolism, resulting in, for example, facilitation of glucose and lipid uptake and amelioration of insulin resistance, and other effects that are important in the treatment of type 2 diabetes. Peroxisome proliferator-activated receptor γ partial agonists are compounds with diminished agonist efficacy compared to full agonists; however, they maintain the antidiabetic effect of full agonists but do not induce the same magnitude of side effects. This mini-review gives a short introduction to in silico screening methods and recent research advances using computational approaches to identify peroxisome proliferator-activated receptor γ agonists, especially partial agonists, from natural sources and how these ligands bind to the peroxisome proliferator-activated receptor γ in order to better understand their biological effects.}, ISSN = {0032-0943}, DOI = {10.1055/s-0034-1383119}, url = {https://www.thieme-connect.de/products/ejournals/pdf/10.1055/s-0034-1383119.pdf}, year = {2015}, type = {Journal Article} }  x  Identification of PPARγ Agonists from Natural Sources Using Different In Silico Approaches

Peroxisome proliferator-activated receptor γ plays an important role in lipid and glucose homeostasis and is the target of many drug discovery investigations because of its role in diseases such as type 2 diabetes. Activation of peroxisome proliferator-activated receptor γ by agonists leads to a conformational change in the ligand-binding domain altering the transcription of several target genes involved in glucose and lipid metabolism, resulting in, for example, facilitation of glucose and lipid uptake and amelioration of insulin resistance, and other effects that are important in the treatment of type 2 diabetes. Peroxisome proliferator-activated receptor γ partial agonists are compounds with diminished agonist efficacy compared to full agonists; however, they maintain the antidiabetic effect of full agonists but do not induce the same magnitude of side effects. This mini-review gives a short introduction to in silico screening methods and recent research advances using computational approaches to identify peroxisome proliferator-activated receptor γ agonists, especially partial agonists, from natural sources and how these ligands bind to the peroxisome proliferator-activated receptor γ in order to better understand their biological effects.

[99]

S. Grosskopf, C. Eckert, C. Arkona, S. Radetzki, K. Böhm, U. Heinemann, G. Wolber, J. v. Kries, W. Birchmeier, and J. Rademann. Selective inhibitors of the protein tyrosine phosphatase SHP2 block cellular motility and growth of cancer cells in-vitro and in-vivo, ChemMedChem, 10(5):815-826, 2015.
Links: [doi:10.1002/cmdc.201500015] [show BibTeX] [show abstract]  x  @article{RN172, author = {Grosskopf, Stefanie and Eckert, Chris and Arkona, Christoph and Radetzki, Silke and Böhm, Kerstin and Heinemann, Udo and Wolber, Gerhard and Kries, Jens-Peter von and Birchmeier, Walter and Rademann, Jörg}, title = {Selective inhibitors of the protein tyrosine phosphatase SHP2 block cellular motility and growth of cancer cells in-vitro and in-vivo}, journal = {Chemmedchem}, volume = {10}, number = {5}, pages = {815-826}, abstract = {Selective inhibitors of the protein tyrosine phosphatase SHP2 (PTPN11), an enzyme, deregulated in numerous human tumors, were generated by combination of chemical synthesis with structure-based rational design. 70 pyridazolon-4-ylidene-hydrazinyl-benzene sulfonates were prepared and evaluated in enzyme assays. Binding modes of active inhibitors were simulated in silico using a newly generated crystal structure of SHP2. The most powerful molecule 25 (GS-493) inhibited SHP2 with an IC50 value of 71 ± 15 nM in the enzyme assay and was 29- and 45-fold more active than against related SHP1 and PTP1B. In cell culture experiments 25 blocked HGF-stimulated epithelial-mesenchymal transition of human pancreatic tumor cells HPAF as indicated by the reduction of minimum neighbor distances of cells. Moreover, 25 inhibited cell colony formation of the non-small cell lung cancer cell line LXFA 526L in soft agar. Finally, it inhibited tumor growth in a murine xenograft model. Thus, the novel specific molecule strengthens the hypothesis that SHP2 is a relevant protein target for the inhibition of mobility and invasiveness of cancer cells.}, DOI = {10.1002/cmdc.201500015}, url = {http://onlinelibrary.wiley.com/doi/10.1002/cmdc.201500015/abstract https://onlinelibrary.wiley.com/doi/pdf/10.1002/cmdc.201500015}, year = {2015}, type = {Journal Article} }  x  Selective inhibitors of the protein tyrosine phosphatase SHP2 block cellular motility and growth of cancer cells in-vitro and in-vivo

Selective inhibitors of the protein tyrosine phosphatase SHP2 (PTPN11), an enzyme, deregulated in numerous human tumors, were generated by combination of chemical synthesis with structure-based rational design. 70 pyridazolon-4-ylidene-hydrazinyl-benzene sulfonates were prepared and evaluated in enzyme assays. Binding modes of active inhibitors were simulated in silico using a newly generated crystal structure of SHP2. The most powerful molecule 25 (GS-493) inhibited SHP2 with an IC50 value of 71 ± 15 nM in the enzyme assay and was 29- and 45-fold more active than against related SHP1 and PTP1B. In cell culture experiments 25 blocked HGF-stimulated epithelial-mesenchymal transition of human pancreatic tumor cells HPAF as indicated by the reduction of minimum neighbor distances of cells. Moreover, 25 inhibited cell colony formation of the non-small cell lung cancer cell line LXFA 526L in soft agar. Finally, it inhibited tumor growth in a murine xenograft model. Thus, the novel specific molecule strengthens the hypothesis that SHP2 is a relevant protein target for the inhibition of mobility and invasiveness of cancer cells.

[98]

C. Meinguet, C. Bruyère, R. Frédérick, V. Mathieu, C. Vancraeynest, L. Pochet, J. Laloy, J. Mortier, G. Wolber, R. Kiss, B. Masereel, and J. Wouters. 3D-QSAR, design, synthesis and characterization of trisubstituted harmine derivatives with in vitro antiproliferative properties, Eur J Med Chem, 94:45-55, 2015.
Links: [doi:10.1016/j.ejmech.2015.02.044] [show BibTeX] [show abstract]  x  @article{RN169, author = {Meinguet, Céline and Bruyère, Céline and Frédérick, Raphaël and Mathieu, Véronique and Vancraeynest, Christelle and Pochet, Lionel and Laloy, Julie and Mortier, Jérémie and Wolber, Gerhard and Kiss, Robert and Masereel, Bernard and Wouters, Johan}, title = {3D-QSAR, design, synthesis and characterization of trisubstituted harmine derivatives with in vitro antiproliferative properties}, journal = {European Journal of Medicinal Chemistry}, volume = {94}, pages = {45-55}, abstract = {Apolar trisubstituted derivatives of harmine show high antiproliferative activity on diverse cancer cell lines. However, these molecules present a poor solubility making these compounds poorly bioavailable. Here, new compounds were synthesized in order to improve solubility while retaining antiproliferative activity. First, polar substituents have shown a higher solubility but a loss of antiproliferative activity. Second, a Comparative Molecular Field Analysis (CoMFA) model was developed, guiding the design and synthesis of eight new compounds. Characterization has underlined the in vitro antiproliferative character of these compounds on five cancerous cell lines, combining with a high solubility at physiological pH, making these molecules druggable. Moreover, targeting glioma treatment, human intestinal absorption and blood brain penetration have been calculated, showing high absorption and penetration properties.}, keywords = {Harmine derivatives Antiproliferative activity Cytostatic activity Comparative Molecular Field Analysis}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2015.02.044}, url = {http://www.sciencedirect.com/science/article/pii/S0223523415001403 http://ac.els-cdn.com/S0223523415001403/1-s2.0-S0223523415001403-main.pdf?_tid= f547ccae-c00a-11e4-8b31-00000aab0f01&acdnat=1425211582_cb6d118f6d7adec74c3f2a725b13dbdb}, year = {2015}, type = {Journal Article} }  x  3D-QSAR, design, synthesis and characterization of trisubstituted harmine derivatives with in vitro antiproliferative properties

Apolar trisubstituted derivatives of harmine show high antiproliferative activity on diverse cancer cell lines. However, these molecules present a poor solubility making these compounds poorly bioavailable. Here, new compounds were synthesized in order to improve solubility while retaining antiproliferative activity. First, polar substituents have shown a higher solubility but a loss of antiproliferative activity. Second, a Comparative Molecular Field Analysis (CoMFA) model was developed, guiding the design and synthesis of eight new compounds. Characterization has underlined the in vitro antiproliferative character of these compounds on five cancerous cell lines, combining with a high solubility at physiological pH, making these molecules druggable. Moreover, targeting glioma treatment, human intestinal absorption and blood brain penetration have been calculated, showing high absorption and penetration properties.

[97]

J. Mortier, E. K. Nyakatura, O. Reimann, S. Huhmann, J. O. Daldrop, C. Baldauf, G. Wolber, M. S. Miettinen, and B. Koksch. Coiled-coils in phage display screening: Insight into exceptional selectivity provided by molecular dynamics, J Chem Inf Model, 55(3):495-500, 2015.
Links: [doi:10.1021/ci500689c] [show BibTeX] [show abstract]  x  @article{RN160, author = {Mortier, J. and Nyakatura, E. K. and Reimann, O. and Huhmann, S. and Daldrop, J. O. and Baldauf, C. and Wolber, G. and Miettinen, M. S. and Koksch, B.}, title = {Coiled-coils in phage display screening: Insight into exceptional selectivity provided by molecular dynamics}, journal = {Journal of Chemical Information and Modeling}, volume = {55}, number = {3}, pages = {495-500}, note = {Mortier, Jeremie Nyakatura, Elisabeth K Reimann, Oliver Huhmann, Susanne Daldrop, Jan O Baldauf, Carsten Wolber, Gerhard Miettinen, Markus S Koksch, Beate ENG 2015/02/05 06:00 J Chem Inf Model. 2015 Feb 12.}, abstract = {Involved in numerous key biological functions, protein helix-helix interactions follow a well-defined intermolecular recognition pattern. The characteristic structure of the alpha-helical coiled-coil allows for the specific randomization of clearly defined interaction partners within heteromeric systems. In this work, a rationally designed heterodimeric coiled-coil was used to investigate potential factors influencing the sequence selectivity in interhelical interactions.}, ISSN = {1549-960X (Electronic) 1549-9596 (Linking)}, DOI = {10.1021/ci500689c}, url = {http://www.ncbi.nlm.nih.gov/pubmed/25648076 http://pubs.acs.org/doi/pdfplus/10.1021/ci500689c}, year = {2015}, type = {Journal Article} }  x  Coiled-coils in phage display screening: Insight into exceptional selectivity provided by molecular dynamics

Involved in numerous key biological functions, protein helix-helix interactions follow a well-defined intermolecular recognition pattern. The characteristic structure of the alpha-helical coiled-coil allows for the specific randomization of clearly defined interaction partners within heteromeric systems. In this work, a rationally designed heterodimeric coiled-coil was used to investigate potential factors influencing the sequence selectivity in interhelical interactions.

[96]

J. Mortier, C. Rakers, M. Bermudez, M. S. Murgueitio, S. Riniker, and G. Wolber. The impact of molecular dynamics on drug design: applications for the characterization of ligand-macromolecule complexes, Drug Discov Today, 20(6):686-702, 2015.
Links: [doi:10.1016/j.drudis.2015.01.003] [show BibTeX] [show abstract]  x  @article{RN162, author = {Mortier, J. and Rakers, C. and Bermudez, M. and Murgueitio, M. S. and Riniker, S. and Wolber, G.}, title = {The impact of molecular dynamics on drug design: applications for the characterization of ligand-macromolecule complexes}, journal = {Drug Discov Today}, volume = {20}, number = {6}, pages = {686-702}, note = {Mortier, Jeremie Rakers, Christin Bermudez, Marcel Murgueitio, Manuela S Riniker, Sereina Wolber, Gerhard ENG REVIEW 2015/01/24 06:00 Drug Discov Today. 2015 Jan 20. pii: S1359-6446(15)00021-5. doi: 10.1016/j.drudis.2015.01.003.}, abstract = {Among all tools available to design new drugs, molecular dynamics (MD) simulations have become an essential technique. Initially developed to investigate molecular models with a limited number of atoms, computers now enable investigations of large macromolecular systems with a simulation time reaching the microsecond range. The reviewed articles cover four years of research to give an overview on the actual impact of MD on the current medicinal chemistry landscape with a particular emphasis on studies of ligand-protein interactions. With a special focus on studies combining computational approaches with data gained from other techniques, this review shows how deeply embedded MD simulations are in drug design strategies and articulates what the future of this technique could be.}, keywords = {software}, ISSN = {1878-5832 (Electronic) 1359-6446 (Linking)}, DOI = {10.1016/j.drudis.2015.01.003}, url = {http://ac.els-cdn.com/S1359644615000215/1-s2.0-S1359644615000215-main.pdf?_tid=fd77aa3e-c00a-11e4-b562-00000aab0f6b&acdnat=1425211596_ad8df81890ab97631dd774ae4cbe1b41}, year = {2015}, type = {Journal Article} }  x  The impact of molecular dynamics on drug design: applications for the characterization of ligand-macromolecule complexes

Among all tools available to design new drugs, molecular dynamics (MD) simulations have become an essential technique. Initially developed to investigate molecular models with a limited number of atoms, computers now enable investigations of large macromolecular systems with a simulation time reaching the microsecond range. The reviewed articles cover four years of research to give an overview on the actual impact of MD on the current medicinal chemistry landscape with a particular emphasis on studies of ligand-protein interactions. With a special focus on studies combining computational approaches with data gained from other techniques, this review shows how deeply embedded MD simulations are in drug design strategies and articulates what the future of this technique could be.

[95]

M. K. Parr, F. Botrè, A. Naß, J. Hengevoss, P. Diel, and G. Wolber. Ecdysteroids: A novel class of anabolic agents?, Biol Sport, 32(2):169-173, 2015.
Links: [doi:10.5604/20831862.1144420] [show BibTeX] [show abstract]  x  @article{RN170, author = {Parr, Maria Kristina and Botrè, Francesco and Naß, Alexandra and Hengevoss, Jonas and Diel, Patrick and Wolber, Gerhard}, title = {Ecdysteroids: A novel class of anabolic agents?}, journal = {Biology of Sport}, volume = {32}, number = {2}, pages = {169-173}, abstract = {Increasing numbers of dietary supplements with ecdysteroids are marketed as "natural anabolic agents". Results of recent studies suggested that their anabolic effect is mediated by estrogen receptor (ER) binding. Within this study the anabolic potency of ecdysterone was compared to well characterized anabolic substances. Effects on the fiber sizes of the soleus muscle in rats as well the diameter of C2C12 derived myotubes were used as biological readouts. Ecdysterone exhibited a strong hypertrophic effect on the fiber size of rat soleus muscle that was found even stronger compared to the test compounds metandienone (dianabol), estradienedione (trenbolox), and SARM S 1, all administered in the same dose (5 mg/kg body weight, for 21 days). In C2C12 myotubes ecdysterone (1 uM) induced a significant increase of the diameter comparable to dihydrotestosterone (1 uM) and IGF 1 (1.3 nM). Molecular docking experiments supported the ERβ mediated action of ecdysterone. To clarify its status in sports, ecdysterone should be considered to be included in the class "S1.2 Other Anabolic Agents" of the list of prohibited substances of the World Anti-Doping Agency.}, DOI = {10.5604/20831862.1144420}, url = {http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4447764/pdf/JBS-32-1144420.pdf}, year = {2015}, type = {Journal Article} }  x  Ecdysteroids: A novel class of anabolic agents?

Increasing numbers of dietary supplements with ecdysteroids are marketed as "natural anabolic agents". Results of recent studies suggested that their anabolic effect is mediated by estrogen receptor (ER) binding. Within this study the anabolic potency of ecdysterone was compared to well characterized anabolic substances. Effects on the fiber sizes of the soleus muscle in rats as well the diameter of C2C12 derived myotubes were used as biological readouts. Ecdysterone exhibited a strong hypertrophic effect on the fiber size of rat soleus muscle that was found even stronger compared to the test compounds metandienone (dianabol), estradienedione (trenbolox), and SARM S 1, all administered in the same dose (5 mg/kg body weight, for 21 days). In C2C12 myotubes ecdysterone (1 uM) induced a significant increase of the diameter comparable to dihydrotestosterone (1 uM) and IGF 1 (1.3 nM). Molecular docking experiments supported the ERβ mediated action of ecdysterone. To clarify its status in sports, ecdysterone should be considered to be included in the class "S1.2 Other Anabolic Agents" of the list of prohibited substances of the World Anti-Doping Agency.

[94]

A. Perdih, M. Hrast, K. Pureber, H. Barreteau, S. Grdadolnik, D. Kocjan, S. Gobec, T. Solmajer, and G. Wolber. Furan-based benzene mono- and dicarboxylic acid derivatives as multiple inhibitors of the bacterial Mur ligases (MurC-MurF): experimental and computational characterization, J Comput Aided Mol Des, :1-20, 2015.
Links: [doi:10.1007/s10822-015-9843-6] [show BibTeX] [show abstract]  x  @article{RN174, author = {Perdih, Andrej and Hrast, Martina and Pureber, Kaja and Barreteau, Hélène and Grdadolnik, SimonaGolič and Kocjan, Darko and Gobec, Stanislav and Solmajer, Tom and Wolber, Gerhard}, title = {Furan-based benzene mono- and dicarboxylic acid derivatives as multiple inhibitors of the bacterial Mur ligases (MurC-MurF): experimental and computational characterization}, journal = {Journal of Computer-Aided Molecular Design}, pages = {1-20}, abstract = {Bacterial resistance to the available antibiotic agents underlines an urgent need for the discovery of novel antibacterial agents. Members of the bacterial Mur ligase family MurC-MurF involved in the intracellular stages of the bacterial peptidoglycan biosynthesis have recently emerged as a collection of attractive targets for novel antibacterial drug design. In this study, we have first extended the knowledge of the class of furan-based benzene-1,3-dicarboxylic acid derivatives by first showing a multiple MurC-MurF ligase inhibition for representatives of the extended series of this class. Steady-state kinetics studies on the MurD enzyme were performed for compound 1, suggesting a competitive inhibition with respect to ATP. To the best of our knowledge, compound 1 represents the first ATP-competitive MurD inhibitor reported to date with concurrent multiple inhibition of all four Mur ligases (MurC-MurF). Subsequent molecular dynamic (MD) simulations coupled with interaction energy calculations were performed for two alternative in silico models of compound 1 in the UMA/D-Glu- and ATP-binding sites of MurD, identifying binding in the ATP-binding site as energetically more favorable in comparison to the UMA/D-Glu-binding site, which was in agreement with steady-state kinetic data. In the final stage, based on the obtained MD data novel furan-based benzene monocarboxylic acid derivatives 8-11, exhibiting multiple Mur ligase (MurC-MurF) inhibition with predominantly superior ligase inhibition over the original series, were discovered and for compound 10 it was shown to possess promising antibacterial activity against S. aureus. These compounds represent novel leads that could by further optimization pave the way to novel antibacterial agents. }, keywords = {Bacterial Mur (MurC–MurF) ligase ATP-competitive inhibition Molecular dynamics (MD) Steady-state kinetics measurements Antibacterial agents Drug design}, ISSN = {0920-654X}, DOI = {10.1007/s10822-015-9843-6}, url = {http://dx.doi.org/10.1007/s10822-015-9843-6 http://download.springer.com/static/pdf/718/art%253A10.1007%252Fs10822-015-9843-6.pdf?originUrl= http%3A%2F%2Flink.springer.com%2Farticle%2F10.1007%2Fs10822-015-9843-6&token2=exp=1444917652~acl=%2Fstatic%2Fpdf%2F718%2Fart%25253A10.1007%25252Fs10822-015-9843-6.pdf%3ForiginUrl%3Dhttp%253A%252F%252Flink.springer.com%252Farticle%252F10.1007%252Fs10822-015-9843-6*~hmac=4f2c8e6a70f3ecc9b08f6110e685bc18eddcae8b3233d8a3acaff9ac2b51bdc2}, year = {2015}, type = {Journal Article} }  x  Furan-based benzene mono- and dicarboxylic acid derivatives as multiple inhibitors of the bacterial Mur ligases (MurC-MurF): experimental and computational characterization

Bacterial resistance to the available antibiotic agents underlines an urgent need for the discovery of novel antibacterial agents. Members of the bacterial Mur ligase family MurC-MurF involved in the intracellular stages of the bacterial peptidoglycan biosynthesis have recently emerged as a collection of attractive targets for novel antibacterial drug design. In this study, we have first extended the knowledge of the class of furan-based benzene-1,3-dicarboxylic acid derivatives by first showing a multiple MurC-MurF ligase inhibition for representatives of the extended series of this class. Steady-state kinetics studies on the MurD enzyme were performed for compound 1, suggesting a competitive inhibition with respect to ATP. To the best of our knowledge, compound 1 represents the first ATP-competitive MurD inhibitor reported to date with concurrent multiple inhibition of all four Mur ligases (MurC-MurF). Subsequent molecular dynamic (MD) simulations coupled with interaction energy calculations were performed for two alternative in silico models of compound 1 in the UMA/D-Glu- and ATP-binding sites of MurD, identifying binding in the ATP-binding site as energetically more favorable in comparison to the UMA/D-Glu-binding site, which was in agreement with steady-state kinetic data. In the final stage, based on the obtained MD data novel furan-based benzene monocarboxylic acid derivatives 8-11, exhibiting multiple Mur ligase (MurC-MurF) inhibition with predominantly superior ligase inhibition over the original series, were discovered and for compound 10 it was shown to possess promising antibacterial activity against S. aureus. These compounds represent novel leads that could by further optimization pave the way to novel antibacterial agents.

[93]

C. Rakers, M. Bermudez, B. G. Keller, J. Mortier, and G. Wolber. Computational close up on protein-protein interactions: how to unravel the invisible using molecular dynamics simulations?, Wiley Interdisciplinary Reviews: Computational Molecular Science, 5(5):345-359, 2015.
Links: [doi:10.1002/wcms.1222] [show BibTeX] [show abstract]  x  @article{RN176, author = {Rakers, Christin and Bermudez, Marcel and Keller, Bettina G. and Mortier, Jérémie and Wolber, Gerhard}, title = {Computational close up on protein-protein interactions: how to unravel the invisible using molecular dynamics simulations?}, journal = {Wiley Interdisciplinary Reviews: Computational Molecular Science}, volume = {5}, number = {5}, pages = {345-359}, abstract = {As an essential part of many biological processes, protein–protein interactions (PPIs) offer exciting and promising opportunities for drug discovery by extension of the druggable target space. Over the last decade, studies on protein networks have significantly increased the number of identified PPIs. However, despite steadily growing data on PPIs, detailed understanding of the interaction surfaces and their dynamics remains limited. Furthermore, the development of small‐molecule inhibitors of PPIs faces technological challenges, leaving the question about the ‘druggability’ of PPIs open. Molecular dynamics (MD) simulations may facilitate the prediction of druggable binding sites on protein–protein interfaces by detecting binding hot spots and transient pockets. MD allows for a detailed analysis of structural and functional aspects of PPIs and thus provides valuable insights into PPI mechanisms and supports the design of PPI modulators. We provide an overview on the main areas of MD applications to PPIs including structural investigations and the design of PPI disruptors. Emphasizing the beneficial synergies between computational and experimental techniques, MD techniques are also frequently applied to low‐resolution structural data and have been used to elucidate structure and movements of complex macromolecular structures relevant for biological processes.}, DOI = {10.1002/wcms.1222}, url = {http://onlinelibrary.wiley.com/doi/10.1002/wcms.1222/abstract http://onlinelibrary.wiley.com/store/10.1002/wcms.1222/asset/wcms1222.pdf?v= 1&t=ii1ppzby&s=c5ce7829a968b92bb67ba6f3cc35285d70cee2ca}, year = {2015}, type = {Journal Article} }  x  Computational close up on protein-protein interactions: how to unravel the invisible using molecular dynamics simulations?

As an essential part of many biological processes, protein–protein interactions (PPIs) offer exciting and promising opportunities for drug discovery by extension of the druggable target space. Over the last decade, studies on protein networks have significantly increased the number of identified PPIs. However, despite steadily growing data on PPIs, detailed understanding of the interaction surfaces and their dynamics remains limited. Furthermore, the development of small‐molecule inhibitors of PPIs faces technological challenges, leaving the question about the ‘druggability’ of PPIs open. Molecular dynamics (MD) simulations may facilitate the prediction of druggable binding sites on protein–protein interfaces by detecting binding hot spots and transient pockets. MD allows for a detailed analysis of structural and functional aspects of PPIs and thus provides valuable insights into PPI mechanisms and supports the design of PPI modulators. We provide an overview on the main areas of MD applications to PPIs including structural investigations and the design of PPI disruptors. Emphasizing the beneficial synergies between computational and experimental techniques, MD techniques are also frequently applied to low‐resolution structural data and have been used to elucidate structure and movements of complex macromolecular structures relevant for biological processes.

[92]

V. Asante, J. Mortier, G. Wolber, and B. Koksch. Impact of fluorination on proteolytic stability of peptides: a case study with α-chymotrypsin and pepsin, Amino Acids, 46(12):2733-2744, 2014.
Links: [doi:10.1007/s00726-014-1819-7] [show BibTeX] [show abstract]  x  @article{RN147, author = {Asante, Vivian and Mortier, Jérémie and Wolber, Gerhard and Koksch, Beate}, title = {Impact of fluorination on proteolytic stability of peptides: a case study with α-chymotrypsin and pepsin}, journal = {Amino Acids}, volume = {46}, number = {12}, pages = {2733-2744}, abstract = {Protease stability is a key consideration in the development of peptide-based drugs. A major approach to increase the bioavailability of pharmacologically active peptides is the incorporation of non-natural amino acids. Due to the unique properties of fluorine, fluorinated organic molecules have proven useful in the development of therapeutically active small molecules as well as in materials and crop science. This study presents data on the ability of fluorinated amino acids to influence proteolytic stability when present in peptide sequences that are based on ideal protease substrates. Different model peptides containing fluorinated amino acids or ethylglycine in the P2, P1′or P2′ positions were designed according to the specificities of the serine protease, α-chymotrypsin (EC 3.4.21.1) or the aspartic protease, pepsin (EC 3.4.23.1). The proteolytic stability of the peptides toward these enzymes was determined by an analytical RP-HPLC assay with fluorescence detection and compared to a control sequence. Molecular modeling was used to support the interpretation of the structure–activity relationship based on the analysis of potential ligand-enzyme interactions. Surprisingly, an increase in proteolytic stability was observed only in a few cases. Thus, this systematic study shows that the proteolytic stability of fluorinated peptides is not predictable, but rather is a very complex phenomenon that depends on the particular enzyme, the position of the substitution relative to the cleavage site and the fluorine content of the side chain.}, keywords = {Chymotrypsin Pepsin Aminobutyric acid Difluoroethylglycine Trifluoroethylglycine}, ISSN = {0939-4451}, DOI = {10.1007/s00726-014-1819-7}, year = {2014}, type = {Journal Article} }  x  Impact of fluorination on proteolytic stability of peptides: a case study with α-chymotrypsin and pepsin

Protease stability is a key consideration in the development of peptide-based drugs. A major approach to increase the bioavailability of pharmacologically active peptides is the incorporation of non-natural amino acids. Due to the unique properties of fluorine, fluorinated organic molecules have proven useful in the development of therapeutically active small molecules as well as in materials and crop science. This study presents data on the ability of fluorinated amino acids to influence proteolytic stability when present in peptide sequences that are based on ideal protease substrates. Different model peptides containing fluorinated amino acids or ethylglycine in the P2, P1′or P2′ positions were designed according to the specificities of the serine protease, α-chymotrypsin (EC 3.4.21.1) or the aspartic protease, pepsin (EC 3.4.23.1). The proteolytic stability of the peptides toward these enzymes was determined by an analytical RP-HPLC assay with fluorescence detection and compared to a control sequence. Molecular modeling was used to support the interpretation of the structure–activity relationship based on the analysis of potential ligand-enzyme interactions. Surprisingly, an increase in proteolytic stability was observed only in a few cases. Thus, this systematic study shows that the proteolytic stability of fluorinated peptides is not predictable, but rather is a very complex phenomenon that depends on the particular enzyme, the position of the substitution relative to the cleavage site and the fluorine content of the side chain.

[91]

S. A. Galal, S. H. M. Khairat, F. A. F. Ragab, A. S. Abdelsamie, M. M. Ali, S. M. Soliman, J. Mortier, G. Wolber, and H. I. El Diwani. Design, synthesis and molecular docking study of novel quinoxalin-2(1H)-ones as anti-tumor active agents with inhibition of tyrosine kinase receptor and studying their cyclooxygenase-2 activity, Eur J Med Chem, 86:122-132, 2014.
Links: [doi:10.1016/j.ejmech.2014.08.048] [show BibTeX] [show abstract]  x  @article{RN152, author = {Galal, Shadia A. and Khairat, Sarah H. M. and Ragab, Fatma A. F. and Abdelsamie, Ahmed S. and Ali, Mamdouh M. and Soliman, Salwa M. and Mortier, Jérémie and Wolber, Gerhard and El Diwani, Hoda I.}, title = {Design, synthesis and molecular docking study of novel quinoxalin-2(1H)-ones as anti-tumor active agents with inhibition of tyrosine kinase receptor and studying their cyclooxygenase-2 activity}, journal = {European Journal of Medicinal Chemistry}, volume = {86}, number = {0}, pages = {122-132}, abstract = {On continuation to our work, new quinoxalin-2(1H)-ones were synthesized to study their cytotoxic effect against HepG-2 and MCF-7 with their effect on the human tyrosine kinase (TRK). Compounds 12, 18, 15, 13, 11a, 20 and 16, respectively, were found to be more potent than cisplatin against HepG2 and selective to TRK. Also, compounds 12, 18, 20, 13, 14, and 22, respectively, exhibited decidedly activity against MCF-7 and selectivity against human TRK compared to cisplatin. A molecular docking study was also performed to gain comprehensive understanding into plausible binding modes and to conclude the structure activity relationships of the synthesized compounds. Moreover, anti-inflammatory activity was studied. Compounds 12, 15, 18 and 22 were found to be potent and selective against COX-2.}, keywords = {Synthesis Quinoxalines Antitumor activity Cyclooxygenase-2 Docking Protein tyrosine kinase}, ISSN = {0223-5234}, DOI = {10.1016/j.ejmech.2014.08.048}, url = {http://www.sciencedirect.com/science/article/pii/S0223523414007831 http://ac.els-cdn.com/S0223523414007831/1-s2.0-S0223523414007831-main.pdf?_tid= b482ad88-a00b-11e5-8f62-00000aacb361&acdnat=1449840963_a223020762d86fd4b9cb81d2db1509d5}, year = {2014}, type = {Journal Article} }  x  Design, synthesis and molecular docking study of novel quinoxalin-2(1H)-ones as anti-tumor active agents with inhibition of tyrosine kinase receptor and studying their cyclooxygenase-2 activity

On continuation to our work, new quinoxalin-2(1H)-ones were synthesized to study their cytotoxic effect against HepG-2 and MCF-7 with their effect on the human tyrosine kinase (TRK). Compounds 12, 18, 15, 13, 11a, 20 and 16, respectively, were found to be more potent than cisplatin against HepG2 and selective to TRK. Also, compounds 12, 18, 20, 13, 14, and 22, respectively, exhibited decidedly activity against MCF-7 and selectivity against human TRK compared to cisplatin. A molecular docking study was also performed to gain comprehensive understanding into plausible binding modes and to conclude the structure activity relationships of the synthesized compounds. Moreover, anti-inflammatory activity was studied. Compounds 12, 15, 18 and 22 were found to be potent and selective against COX-2.

[90]

D. Kotowska, R. B. El-Houri, K. Borkowski, R. K. Petersen, X. C. Fretté, G. Wolber, K. Grevsen, K. B. Christensen, L. P. Christensen, and K. Kristiansen. Isomeric C12-alkamides from the roots of Echinacea Purpurea improve basal and insulin-dependent glucose uptake in 3T3-L1 adipocytes, Planta Med, 80(18):1712-1720, 2014.
Links: [doi:10.1055/s-0034-1383252] [show BibTeX]  x  @article{RN155, author = {Kotowska, Dorota and El-Houri, Rime B. and Borkowski, Kamil and Petersen, Rasmus K. and Fretté, Xavier C. and Wolber, Gerhard and Grevsen, Kai and Christensen, Kathrine B. and Christensen, Lars P. and Kristiansen, Karsten}, title = {Isomeric C12-alkamides from the roots of Echinacea Purpurea improve basal and insulin-dependent glucose uptake in 3T3-L1 adipocytes}, journal = {Planta Medica}, volume = {80}, number = {18}, pages = {1712-1720}, ISSN = {0032-0943}, DOI = {10.1055/s-0034-1383252}, url = {https://www.thieme-connect.com/products/ejournals/pdf/10.1055/s-0034-1383252.pdf}, year = {2014}, type = {Journal Article} }

[89]

M. S. Murgueitio, P. Henneke, H. Glossmann, S. Santos-Sierra, and G. Wolber. Prospective virtual screening in a sparse data scenario: design of small-molecule TLR2 antagonists, ChemMedChem, 9(4):813-822, 2014.
Links: [doi:10.1002/Cmdc.201300445] [show BibTeX] [show abstract]  x  @article{RN3, author = {Murgueitio, M. S. and Henneke, P. and Glossmann, H. and Santos-Sierra, S. and Wolber, G.}, title = {Prospective virtual screening in a sparse data scenario: design of small-molecule TLR2 antagonists}, journal = {Chemmedchem}, volume = {9}, number = {4}, pages = {813-822}, note = {Ae1se Times Cited:0 Cited References Count:36}, abstract = {Toll-like receptors (TLRs) are critical signaling molecules with roles in various severe clinical conditions such as sepsis and rheumatoid arthritis, and have therefore been advocated as promising drug targets for the treatment of these diseases. The aim of this study was to discover small-molecule antagonists of TLR2 by computer-aided drug design. This goal poses several challenges due to the lack of available data on TLR2 modulators. To overcome these hurdles we developed a combined structure- and ligand-based virtual screening approach. First, we calculated molecular interaction fields of the TLR2 binding site to derive a structure-based 3D pharmacophore, which was then used for virtual screening. We then performed a two-step shape- and feature-based similarity search using known TLR2 ligands as query structures. A selection of virtual screening hits was biologically tested in a cell-based assay for TLR2 signaling inhibition, leading to the identification of several compounds with antagonistic activity (IC50 values) in the low-micromolar range.}, keywords = {drug discovery receptors tlr2 antagonists toll-like receptors virtual screening toll-like receptors pattern-recognition receptors pathogen recognition conformer generation structural biology innate immunity binding-sites shape pharmacophores discovery}, ISSN = {1860-7179}, DOI = {10.1002/Cmdc.201300445}, url = {Go to ISI://WOS:000333749200017 http://onlinelibrary.wiley.com/doi/10.1002/cmdc.201300445/abstract https://onlinelibrary.wiley.com/doi/pdf/10.1002/cmdc.201300445}, year = {2014}, type = {Journal Article} }  x  Prospective virtual screening in a sparse data scenario: design of small-molecule TLR2 antagonists

Toll-like receptors (TLRs) are critical signaling molecules with roles in various severe clinical conditions such as sepsis and rheumatoid arthritis, and have therefore been advocated as promising drug targets for the treatment of these diseases. The aim of this study was to discover small-molecule antagonists of TLR2 by computer-aided drug design. This goal poses several challenges due to the lack of available data on TLR2 modulators. To overcome these hurdles we developed a combined structure- and ligand-based virtual screening approach. First, we calculated molecular interaction fields of the TLR2 binding site to derive a structure-based 3D pharmacophore, which was then used for virtual screening. We then performed a two-step shape- and feature-based similarity search using known TLR2 ligands as query structures. A selection of virtual screening hits was biologically tested in a cell-based assay for TLR2 signaling inhibition, leading to the identification of several compounds with antagonistic activity (IC50 values) in the low-micromolar range.

[88]

E. K. Nyakatura, R. R. Araghi, J. Mortier, S. Wieczorek, C. Baldauf, G. Wolber, and B. Koksch. An unusual interstrand h-bond stabilizes the heteroassembly of helical alpha beta gamma-chimeras with natural peptides, ACS Chem Biol, 9(3):613-616, 2014.
Links: [doi:10.1021/Cb4007979] [show BibTeX] [show abstract]  x  @article{RN6, author = {Nyakatura, E. K. and Araghi, R. R. and Mortier, J. and Wieczorek, S. and Baldauf, C. and Wolber, G. and Koksch, B.}, title = {An unusual interstrand h-bond stabilizes the heteroassembly of helical alpha beta gamma-chimeras with natural peptides}, journal = {ACS Chemical Biology}, volume = {9}, number = {3}, pages = {613-616}, note = {Ad7wi Times Cited:0 Cited References Count:32}, abstract = {The substitution of alpha-amino acids by homologated amino acids has a strong impact on the overall structure and topology of peptides, usually leading to a loss in thermal stability. Here, we report on the identification of an ideal core packing between an alpha-helical peptide and an alpha beta gamma-chimera via phage display. Selected peptides assemble with the chimeric sequence with thermal stabilities that are comparable to that of the parent bundle consisting purely of alpha-amino acids. With the help of MD simulations and mutational analysis this stability could be explained by the formation of an interhelical H-bond between the selected cysteine and a backbone carbonyl of the beta/gamma-segment. Gained results can be directly applied in the design of biologically relevant peptides containing beta- and gamma-amino acids.}, keywords = {phage display amino-acids foldamers proteins conformations backbone residues insights mimicry design}, ISSN = {1554-8929}, DOI = {10.1021/Cb4007979}, url = {Go to ISI://WOS:000333477300005 http://pubs.acs.org/doi/pdfplus/10.1021/cb4007979}, year = {2014}, type = {Journal Article} }  x  An unusual interstrand h-bond stabilizes the heteroassembly of helical alpha beta gamma-chimeras with natural peptides

The substitution of alpha-amino acids by homologated amino acids has a strong impact on the overall structure and topology of peptides, usually leading to a loss in thermal stability. Here, we report on the identification of an ideal core packing between an alpha-helical peptide and an alpha beta gamma-chimera via phage display. Selected peptides assemble with the chimeric sequence with thermal stabilities that are comparable to that of the parent bundle consisting purely of alpha-amino acids. With the help of MD simulations and mutational analysis this stability could be explained by the formation of an interhelical H-bond between the selected cysteine and a backbone carbonyl of the beta/gamma-segment. Gained results can be directly applied in the design of biologically relevant peptides containing beta- and gamma-amino acids.

[87]

E. K. Nyakatura, J. Mortier, V. S. Radtke, S. Wieczorek, R. Rezaei Araghi, C. Baldauf, G. Wolber, and B. Koksch. β- and γ-amino acids at α-helical interfaces: Toward the formation of highly stable foldameric coiled coils, ACS Medicinal Chemistry Letters, 5(12):1300-1303, 2014.
Links: [doi:10.1021/ml500361c] [show BibTeX] [show abstract]  x  @article{RN154, author = {Nyakatura, Elisabeth K. and Mortier, Jérémie and Radtke, Vanessa S. and Wieczorek, Sebastian and Rezaei Araghi, Raheleh and Baldauf, Carsten and Wolber, Gerhard and Koksch, Beate}, title = {β- and γ-amino acids at α-helical interfaces: Toward the formation of highly stable foldameric coiled coils}, journal = {ACS Medicinal Chemistry Letters}, volume = {5}, number = {12}, pages = {1300-1303}, abstract = {Since peptides are vital for cellular and pathogenic processes, much effort has been put into the design of unnatural oligomers that mimic natural peptide structures, also referred to as foldamers. However, to enable the specific application of foldamers, a thorough characterization of their interaction profiles in native protein environments is required. We report here the application of phage display for the identification of suitable helical environments for a sequence comprising an alternating set of ?- and ?-amino acids. In vitro selected sequences show that an increase in the hydrophobic surface area at the helical interface as well as the incorporation of a polar H-bond donor functionality can significantly improve interhelical interactions involving backbone-extended amino acids. Thus, our data provide insight into the principles of the rational design of foldameric inhibitors for protein?protein interactions.}, DOI = {10.1021/ml500361c}, url = {http://dx.doi.org/10.1021/ml500361c http://pubs.acs.org/doi/pdfplus/10.1021/ml500361c}, year = {2014}, type = {Journal Article} }  x  β- and γ-amino acids at α-helical interfaces: Toward the formation of highly stable foldameric coiled coils

Since peptides are vital for cellular and pathogenic processes, much effort has been put into the design of unnatural oligomers that mimic natural peptide structures, also referred to as foldamers. However, to enable the specific application of foldamers, a thorough characterization of their interaction profiles in native protein environments is required. We report here the application of phage display for the identification of suitable helical environments for a sequence comprising an alternating set of ?- and ?-amino acids. In vitro selected sequences show that an increase in the hydrophobic surface area at the helical interface as well as the incorporation of a polar H-bond donor functionality can significantly improve interhelical interactions involving backbone-extended amino acids. Thus, our data provide insight into the principles of the rational design of foldameric inhibitors for protein?protein interactions.

[86]

R. Ottana, R. Maccari, J. Mortier, A. Caselli, S. Amuso, G. Camici, A. Rotondo, G. Wolber, and P. Paoli. Synthesis, biological activity and structure-activity relationships of new benzoic acid-based protein tyrosine phosphatase inhibitors endowed with insulinomimetic effects in mouse C2C12 skeletal muscle cells, Eur J Med Chem, 71:112-127, 2014.
Links: [doi:10.1016/J.Ejmech.2013.11.001] [show BibTeX] [show abstract]  x  @article{RN9, author = {Ottana, R. and Maccari, R. and Mortier, J. and Caselli, A. and Amuso, S. and Camici, G. and Rotondo, A. and Wolber, G. and Paoli, P.}, title = {Synthesis, biological activity and structure-activity relationships of new benzoic acid-based protein tyrosine phosphatase inhibitors endowed with insulinomimetic effects in mouse C2C12 skeletal muscle cells}, journal = {European Journal of Medicinal Chemistry}, volume = {71}, pages = {112-127}, note = {Ab0qb Times Cited:0 Cited References Count:70}, abstract = {Insulin resistance is a complex altered metabolic condition characterized by impaired insulin signaling and implicated in the pathogenesis of serious human diseases, such as diabetes, obesity, neurodegenerative pathologies. In pursuing our aim to identify new agents able to improve cellular insulin sensitivity, we have synthesized new 4-[(5-arylidene-4-oxo-2-phenylimino/oxothiazolidin-3-yl)methyl] benzoic acids (5, 8) and evaluated their inhibitory activity towards human protein tyrosine phosphatases PTP1B, LMW-PTP and TCPTP, enzymes which are involved in the development of insulin resistance. Compounds 5 and 8 showed from moderate to significant selectivity toward PTP1B over both the highly homologous TCPTP and the two isoforms of human LMW-PTP. In addition, most of the tested compounds selectively inhibited LMW-PTP IF1 over the isoform IF2. Docking studies into the active sites of PTP1B and LMW-PTP aided the rationalization of the observed PTP inhibitory profile. Moreover, most tested compounds were capable to induce the insulin metabolic pathway in mouse C2C12 skeletal muscle cells by remarkably stimulating both IR beta phosphorylation and 2-deoxyglucose cellular uptake. (C) 2013 Elsevier Masson SAS. All rights reserved.}, keywords = {protein tyrosine phosphatases enzyme inhibitors insulinomimetic effects molecular docking 5-arylidene-4-thiazolidinone derivatives 4-[(5-arylidene-4-oxo-2-phenylimino/oxothiazolidin-3yl)methyl]benzoic acids weight phosphotyrosyl phosphatase increased insulin sensitivity structure-based optimization cardiovascular-disease signal-transduction alzheimers-disease metabolic syndrome diabetes-mellitus leptin resistance crystal-structure}, ISSN = {0223-5234}, DOI = {10.1016/J.Ejmech.2013.11.001}, url = {Go to ISI://WOS:000331496100013 http://ac.els-cdn.com/S0223523413007319/1-s2.0-S0223523413007319-main.pdf?_tid= 9b3132fc-4240-11e4-974e-00000aacb361&acdnat=1411380777_e8fb8750bd8d2cbe6a8717d6177ecfcd}, year = {2014}, type = {Journal Article} }  x  Synthesis, biological activity and structure-activity relationships of new benzoic acid-based protein tyrosine phosphatase inhibitors endowed with insulinomimetic effects in mouse C2C12 skeletal muscle cells

Insulin resistance is a complex altered metabolic condition characterized by impaired insulin signaling and implicated in the pathogenesis of serious human diseases, such as diabetes, obesity, neurodegenerative pathologies. In pursuing our aim to identify new agents able to improve cellular insulin sensitivity, we have synthesized new 4-[(5-arylidene-4-oxo-2-phenylimino/oxothiazolidin-3-yl)methyl] benzoic acids (5, 8) and evaluated their inhibitory activity towards human protein tyrosine phosphatases PTP1B, LMW-PTP and TCPTP, enzymes which are involved in the development of insulin resistance. Compounds 5 and 8 showed from moderate to significant selectivity toward PTP1B over both the highly homologous TCPTP and the two isoforms of human LMW-PTP. In addition, most of the tested compounds selectively inhibited LMW-PTP IF1 over the isoform IF2. Docking studies into the active sites of PTP1B and LMW-PTP aided the rationalization of the observed PTP inhibitory profile. Moreover, most tested compounds were capable to induce the insulin metabolic pathway in mouse C2C12 skeletal muscle cells by remarkably stimulating both IR beta phosphorylation and 2-deoxyglucose cellular uptake. (C) 2013 Elsevier Masson SAS. All rights reserved.

[85]

A. Perdih, M. Hrast, H. Barreteau, S. Gobec, G. Wolber, and T. Solmajer. Benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives as multiple inhibitors of bacterial Mur ligases (MurC-MurF), Bioorg Med Chem, 22(15):4124-4134, 2014.
Links: [doi:10.1016/j.bmc.2014.05.058] [show BibTeX] [show abstract]  x  @article{RN131, author = {Perdih, Andrej and Hrast, Martina and Barreteau, Hélène and Gobec, Stanislav and Wolber, Gerhard and Solmajer, Tom}, title = {Benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives as multiple inhibitors of bacterial Mur ligases (MurC-MurF)}, journal = {Bioorganic & Medicinal Chemistry}, volume = {22}, number = {15}, pages = {4124-4134}, abstract = {Enzymes catalyzing the biosynthesis of bacterial peptidoglycan represent traditionally a collection of highly selective targets for novel antibacterial drug design. Four members of the bacterial Mur ligase family—MurC, MurD, MurE and MurF—are involved in the intracellular steps of peptidoglycan biosynthesis, catalyzing the synthesis of the peptide moiety of the Park’s nucleotide. In our previous virtual screening campaign, a chemical class of benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives exhibiting dual MurD/MurE inhibition properties was discovered. In the present study we further investigated this class of compounds by performing inhibition assays on all four Mur ligases (MurC–MurF). Furthermore, molecular dynamics (MD) simulation studies of one of the initially discovered compound 1 were performed to explore its geometry as well as its energetic behavior based on the Linear Interaction Energy (LIE) method. Further in silico virtual screening (VS) experiments based on the parent active compound 1 were conducted to optimize the discovered series. Selected hits were assayed against all Escherichia coli MurC–MurF enzymes in biochemical inhibition assays and molecules 10–14 containing benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole coupled with five member-ring rhodanine moiety were found to be multiple inhibitors of the whole MurC–MurF cascade of bacterial enzymes in the micromolar range. Steady-state kinetics studies suggested this class to act as competitive inhibitors of the MurD enzyme towards d-Glu. These compounds represent novel valuable starting point in the development of novel antibacterial agents.}, keywords = {Bacterial Mur (MurC–MurF) ligase Structure-based pharmacophores Virtual screening Molecular docking Molecular dynamics (MD) Linear Interaction Energy (LIE) method Antibacterial agents Drug design}, ISSN = {0968-0896}, DOI = {10.1016/j.bmc.2014.05.058}, url = {http://www.sciencedirect.com/science/article/pii/S0968089614004179 http://ac.els-cdn.com/S0968089614004179/1-s2.0-S0968089614004179-main.pdf?_tid= 97a047d6-4240-11e4-8cc9-00000aacb35e&acdnat=1411380771_9a11a24bf370dd0c42a4252548df3aaa}, year = {2014}, type = {Journal Article} }  x  Benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives as multiple inhibitors of bacterial Mur ligases (MurC-MurF)

Enzymes catalyzing the biosynthesis of bacterial peptidoglycan represent traditionally a collection of highly selective targets for novel antibacterial drug design. Four members of the bacterial Mur ligase family—MurC, MurD, MurE and MurF—are involved in the intracellular steps of peptidoglycan biosynthesis, catalyzing the synthesis of the peptide moiety of the Park’s nucleotide. In our previous virtual screening campaign, a chemical class of benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole derivatives exhibiting dual MurD/MurE inhibition properties was discovered. In the present study we further investigated this class of compounds by performing inhibition assays on all four Mur ligases (MurC–MurF). Furthermore, molecular dynamics (MD) simulation studies of one of the initially discovered compound 1 were performed to explore its geometry as well as its energetic behavior based on the Linear Interaction Energy (LIE) method. Further in silico virtual screening (VS) experiments based on the parent active compound 1 were conducted to optimize the discovered series. Selected hits were assayed against all Escherichia coli MurC–MurF enzymes in biochemical inhibition assays and molecules 10–14 containing benzene-1,3-dicarboxylic acid 2,5-dimethylpyrrole coupled with five member-ring rhodanine moiety were found to be multiple inhibitors of the whole MurC–MurF cascade of bacterial enzymes in the micromolar range. Steady-state kinetics studies suggested this class to act as competitive inhibitors of the MurD enzyme towards d-Glu. These compounds represent novel valuable starting point in the development of novel antibacterial agents.

[84]

A. Perdih, M. Hrast, H. Barreteau, S. Gobec, G. Wolber, and T. Solmajer. Inhibitor Design Strategy Based on an Enzyme Structural Flexibility: A Case of Bacterial MurD Ligase, J Chem Inf Model, 54(5):1451-1466, 2014.
Links: [doi:10.1021/Ci500104m] [show BibTeX] [show abstract]  x  @article{RN2, author = {Perdih, A. and Hrast, M. and Barreteau, H. and Gobec, S. and Wolber, G. and Solmajer, T.}, title = {Inhibitor Design Strategy Based on an Enzyme Structural Flexibility: A Case of Bacterial MurD Ligase}, journal = {Journal of Chemical Information and Modeling}, volume = {54}, number = {5}, pages = {1451-1466}, note = {Ai1tj Times Cited:0 Cited References Count:51}, abstract = {Increasing bacterial resistance to available antibiotics stimulated the discovery of novel efficacious antibacterial agents. The biosynthesis of the bacterial peptidoglycan, where the MurD enzyme is involved in the intracellular phase of the UDP-MurNAc-pentapeptide formation, represents a collection of highly selective targets for novel antibacterial drug design. In our previous computational studies, the C-terminal domain motion of the MurD ligase was investigated using Targeted Molecular Dynamic (TMD) simulation and the Off-Path Simulation (OPS) technique. In this study, we present a drug design strategy using multiple protein structures for the identification of novel MurD ligase inhibitors. Our main focus was the ATP-binding site of the MurD enzyme. In the first stage, three MurD protein conformations were selected based on the obtained OPS/TMD data as the initial criterion. Subsequently, a two-stage virtual screening approach was utilized combining derived structure-based pharmacophores with molecular docking calculations. Selected compounds were then assayed in the established enzyme binding assays, and compound 3 from the aminothiazole class was discovered to act as a dual MurC/MurD inhibitor in the micomolar range. A steady-state kinetic study was performed on the MurD enzyme to provide further information about the mechanistic aspects of its inhibition. In the final stage, all used conformations of the MurD enzyme with compound 3 were simulated in classical molecular dynamics (MD) simulations providing atomistic insights of the experimental results. Overall, the study depicts several challenges that need to be addressed when trying to hit a flexible moving target such as the presently studied bacterial MurD enzyme and show the possibilities of how computational tools can be proficiently used at all stages of the drug discovery process.}, keywords = {molecular-dynamics simulation escherichia-coli peptidoglycan biosynthesis protein flexibility drug discovery kinetic mechanism hiv-1 protease adding enzyme force-fields cell-wall}, ISSN = {1549-9596}, DOI = {10.1021/Ci500104m}, url = {Go to ISI://WOS:000336637400016 http://pubs.acs.org/doi/pdfplus/10.1021/ci500104m}, year = {2014}, type = {Journal Article} }  x  Inhibitor Design Strategy Based on an Enzyme Structural Flexibility: A Case of Bacterial MurD Ligase

Increasing bacterial resistance to available antibiotics stimulated the discovery of novel efficacious antibacterial agents. The biosynthesis of the bacterial peptidoglycan, where the MurD enzyme is involved in the intracellular phase of the UDP-MurNAc-pentapeptide formation, represents a collection of highly selective targets for novel antibacterial drug design. In our previous computational studies, the C-terminal domain motion of the MurD ligase was investigated using Targeted Molecular Dynamic (TMD) simulation and the Off-Path Simulation (OPS) technique. In this study, we present a drug design strategy using multiple protein structures for the identification of novel MurD ligase inhibitors. Our main focus was the ATP-binding site of the MurD enzyme. In the first stage, three MurD protein conformations were selected based on the obtained OPS/TMD data as the initial criterion. Subsequently, a two-stage virtual screening approach was utilized combining derived structure-based pharmacophores with molecular docking calculations. Selected compounds were then assayed in the established enzyme binding assays, and compound 3 from the aminothiazole class was discovered to act as a dual MurC/MurD inhibitor in the micomolar range. A steady-state kinetic study was performed on the MurD enzyme to provide further information about the mechanistic aspects of its inhibition. In the final stage, all used conformations of the MurD enzyme with compound 3 were simulated in classical molecular dynamics (MD) simulations providing atomistic insights of the experimental results. Overall, the study depicts several challenges that need to be addressed when trying to hit a flexible moving target such as the presently studied bacterial MurD enzyme and show the possibilities of how computational tools can be proficiently used at all stages of the drug discovery process.

[83]

C. Rakers, S. Schwerdtfeger, J. Mortier, S. Duwe, T. Wolff, G. Wolber, and M. F. Melzig. Inhibitory potency of flavonoid derivatives on influenza virus neuraminidase, Bioorg Med Chem Lett, 24(17):4312-4317, 2014.
Links: [doi:10.1016/j.bmcl.2014.07.010] [show BibTeX] [show abstract]  x  @article{RN130, author = {Rakers, Christin and Schwerdtfeger, Sverre-Morten and Mortier, Jérémie and Duwe, Susanne and Wolff, Thorsten and Wolber, Gerhard and Melzig, Matthias F.}, title = {Inhibitory potency of flavonoid derivatives on influenza virus neuraminidase}, journal = {Bioorganic & Medicinal Chemistry Letters}, volume = {24}, number = {17}, pages = {4312-4317}, abstract = {The constant risk of emerging new influenza virus strains that are resistant to established inhibitors like oseltamivir leaves influenza neuraminidase (NA) a prominent target for drug design. The inhibitory activity of several flavonoid derivatives was experimentally tested in comparison to oseltamivir for the NA expressed by the seasonal influenza virus strains A/California/7/09 (A(H1N1)pdm09), A/Perth/16/09 (A(H3N2)), and B/Brisbane/60/08. IC50 values of polyphenols confirmed moderate inhibition in the μM range. Structurally, the amount and site of glycosylation of tested flavonoids have no significant influence on their inhibitory potency. In a pharmacophore-based docking approach the structure–activity relationship was evaluated. Molecular dynamics simulations revealed highly flexible parts of the enzyme and the contribution of salt bridges to the structural stability of NA. The findings of this study elucidate the impact of flavonoids on viral neuraminidase activity and the analysis of their modes of action provide valuable information about the mechanism of NA inhibition.}, keywords = {Influenza Neuraminidase Flavonoids Molecular dynamics Docking}, ISSN = {0960-894X}, DOI = {10.1016/j.bmcl.2014.07.010}, url = {http://www.sciencedirect.com/science/article/pii/S0960894X14007343 http://ac.els-cdn.com/S0960894X14007343/1-s2.0-S0960894X14007343-main.pdf?_tid= 9244019c-4240-11e4-af5e-00000aab0f27&acdnat=1411380762_b399fa4d56fe704fa20d99c706fd5f57}, year = {2014}, type = {Journal Article} }  x  Inhibitory potency of flavonoid derivatives on influenza virus neuraminidase

The constant risk of emerging new influenza virus strains that are resistant to established inhibitors like oseltamivir leaves influenza neuraminidase (NA) a prominent target for drug design. The inhibitory activity of several flavonoid derivatives was experimentally tested in comparison to oseltamivir for the NA expressed by the seasonal influenza virus strains A/California/7/09 (A(H1N1)pdm09), A/Perth/16/09 (A(H3N2)), and B/Brisbane/60/08. IC50 values of polyphenols confirmed moderate inhibition in the μM range. Structurally, the amount and site of glycosylation of tested flavonoids have no significant influence on their inhibitory potency. In a pharmacophore-based docking approach the structure–activity relationship was evaluated. Molecular dynamics simulations revealed highly flexible parts of the enzyme and the contribution of salt bridges to the structural stability of NA. The findings of this study elucidate the impact of flavonoids on viral neuraminidase activity and the analysis of their modes of action provide valuable information about the mechanism of NA inhibition.

[82]

J. Schmitz, D. van der Mey, M. Bermudez, J. Klöckner, R. Schrage, E. Kostenis, C. Tränkle, G. Wolber, K. Mohr, and U. Holzgrabe. Dualsteric muscarinic antagonists - orthosteric binding pose controls allosteric subtype selectivity, J Med Chem, 57(15):6739-6750, 2014.
Links: [doi:10.1021/jm500790x] [show BibTeX] [show abstract]  x  @article{RN129, author = {Schmitz, Jens and van der Mey, Dorina and Bermudez, Marcel and Klöckner, Jessica and Schrage, Ramona and Kostenis, Evi and Tränkle, Christian and Wolber, Gerhard and Mohr, Klaus and Holzgrabe, Ulrike}, title = {Dualsteric muscarinic antagonists - orthosteric binding pose controls allosteric subtype selectivity}, journal = {Journal of Medicinal Chemistry}, volume = {57}, number = {15}, pages = {6739-6750}, abstract = {Bivalent ligands of G protein-coupled receptors have been shown to simultaneously either bind to two adjacent receptors or to bridge different parts of one receptor protein. Recently, we found that bivalent agonists of muscarinic receptors can simultaneously occupy both the orthosteric transmitter binding site and the allosteric vestibule of the receptor protein. Such dualsteric agonists display a certain extent of subtype selectivity, generate pathway-specific signaling, and in addition may allow for designed partial agonism. Here, we want to extend the concept to bivalent antagonism. Using the phthal- and naphthalimide moieties, which bind to the allosteric, extracellular site, and atropine or scopolamine as orthosteric building blocks, both connected by a hexamethonium linker, we were able to prove a bitopic binding mode of antagonist hybrids for the first time. This is demonstrated by structure–activity relationships, site-directed mutagenesis, molecular docking studies, and molecular dynamics simulations. Findings revealed that a difference in spatial orientation of the orthosteric tropane moiety translates into a divergent M2/M5 subtype selectivity of the corresponding bitopic hybrids.}, keywords = {gpcr}, ISSN = {0022-2623}, DOI = {10.1021/jm500790x}, url = {http://pubs.acs.org/doi/pdfplus/10.1021/jm500790x}, year = {2014}, type = {Journal Article} }  x  Dualsteric muscarinic antagonists - orthosteric binding pose controls allosteric subtype selectivity

Bivalent ligands of G protein-coupled receptors have been shown to simultaneously either bind to two adjacent receptors or to bridge different parts of one receptor protein. Recently, we found that bivalent agonists of muscarinic receptors can simultaneously occupy both the orthosteric transmitter binding site and the allosteric vestibule of the receptor protein. Such dualsteric agonists display a certain extent of subtype selectivity, generate pathway-specific signaling, and in addition may allow for designed partial agonism. Here, we want to extend the concept to bivalent antagonism. Using the phthal- and naphthalimide moieties, which bind to the allosteric, extracellular site, and atropine or scopolamine as orthosteric building blocks, both connected by a hexamethonium linker, we were able to prove a bitopic binding mode of antagonist hybrids for the first time. This is demonstrated by structure–activity relationships, site-directed mutagenesis, molecular docking studies, and molecular dynamics simulations. Findings revealed that a difference in spatial orientation of the orthosteric tropane moiety translates into a divergent M2/M5 subtype selectivity of the corresponding bitopic hybrids.

[81]

M. A. Seiter, S. Salcher, M. Rupp, J. Hagenbuchner, U. Kiechl-Kohlendorfer, J. Mortier, G. Wolber, J. M. Rollinger, P. Obexer, and M. J. Ausserlechner. Discovery of Sanggenon G as a natural cell-permeable small-molecular weight inhibitor of X-linked inhibitor of apoptosis protein (XIAP), FEBS Open Bio, 4:659-671, 2014.
Links: [doi:10.1016/j.fob.2014.07.001] [show BibTeX] [show abstract]  x  @article{RN132, author = {Seiter, Maximilian A. and Salcher, Stefan and Rupp, Martina and Hagenbuchner, Judith and Kiechl-Kohlendorfer, Ursula and Mortier, Jérémie and Wolber, Gerhard and Rollinger, Judith M. and Obexer, Petra and Ausserlechner, Michael J.}, title = {Discovery of Sanggenon G as a natural cell-permeable small-molecular weight inhibitor of X-linked inhibitor of apoptosis protein (XIAP)}, journal = {FEBS Open Bio}, volume = {4}, number = {0}, pages = {659-671}, abstract = {Defects in the regulation of apoptosis are one main cause of cancer development and may result from overexpression of anti-apoptotic proteins such as the X-linked inhibitor of apoptosis protein (XIAP). XIAP is frequently overexpressed in human leukemia and prostate and breast tumors. Inhibition of apoptosis by XIAP is mainly coordinated through direct binding to the initiator caspase-9 via its baculovirus-IAP-repeat-3 (BIR3) domain. XIAP inhibits caspases directly making it to an attractive target for anti-cancer therapy. In the search for novel, non-peptidic XIAP inhibitors in this study we focused on the chemical constituents of sāng bái pí (mulberry root bark). Most promising candidates of this plant were tested biochemically in vitro by a fluorescence polarization (FP) assay and in vivo via protein fragment complementation analysis (PCA). We identified the Diels Alder adduct Sanggenon G (SG1) as a novel, small-molecular weight inhibitor of XIAP. As shown by FP and PCA analyses, SG1 binds specifically to the BIR3 domain of XIAP with a binding affinity of 34.26 μM. Treatment of the transgenic leukemia cell line Molt3/XIAP with SG1 enhances caspase-8, -3 and -9 cleavage, displaces caspase-9 from XIAP as determined by immunoprecipitation experiments and sensitizes these cells to etoposide-induced apoptosis. SG1 not only sensitizes the XIAP-overexpressing leukemia cell line Molt3/XIAP to etoposide treatment but also different neuroblastoma cell lines endogenously expressing high XIAP levels. Taken together, Sanggenon G (SG1) is a novel, natural, non-peptidic, small-molecular inhibitor of XIAP that can serve as a starting point to develop a new class of improved XIAP inhibitors.}, keywords = {application sbdd}, ISSN = {2211-5463}, DOI = {10.1016/j.fob.2014.07.001}, url = {http://www.sciencedirect.com/science/article/pii/S2211546314000655 http://ac.els-cdn.com/S2211546314000655/1-s2.0-S2211546314000655-main.pdf?_tid= 8f475c96-4240-11e4-ad09-00000aacb360&acdnat=1411380757_e7c5cf33054a97e0fc81b36bee35993e}, year = {2014}, type = {Journal Article} }  x  Discovery of Sanggenon G as a natural cell-permeable small-molecular weight inhibitor of X-linked inhibitor of apoptosis protein (XIAP)

Defects in the regulation of apoptosis are one main cause of cancer development and may result from overexpression of anti-apoptotic proteins such as the X-linked inhibitor of apoptosis protein (XIAP). XIAP is frequently overexpressed in human leukemia and prostate and breast tumors. Inhibition of apoptosis by XIAP is mainly coordinated through direct binding to the initiator caspase-9 via its baculovirus-IAP-repeat-3 (BIR3) domain. XIAP inhibits caspases directly making it to an attractive target for anti-cancer therapy. In the search for novel, non-peptidic XIAP inhibitors in this study we focused on the chemical constituents of sāng bái pí (mulberry root bark). Most promising candidates of this plant were tested biochemically in vitro by a fluorescence polarization (FP) assay and in vivo via protein fragment complementation analysis (PCA). We identified the Diels Alder adduct Sanggenon G (SG1) as a novel, small-molecular weight inhibitor of XIAP. As shown by FP and PCA analyses, SG1 binds specifically to the BIR3 domain of XIAP with a binding affinity of 34.26 μM. Treatment of the transgenic leukemia cell line Molt3/XIAP with SG1 enhances caspase-8, -3 and -9 cleavage, displaces caspase-9 from XIAP as determined by immunoprecipitation experiments and sensitizes these cells to etoposide-induced apoptosis. SG1 not only sensitizes the XIAP-overexpressing leukemia cell line Molt3/XIAP to etoposide treatment but also different neuroblastoma cell lines endogenously expressing high XIAP levels. Taken together, Sanggenon G (SG1) is a novel, natural, non-peptidic, small-molecular inhibitor of XIAP that can serve as a starting point to develop a new class of improved XIAP inhibitors.

[80]

A. Temirak, Y. M. Shaker, F. A. F. Ragab, M. M. Ali, S. M. Soliman, J. Mortier, G. Wolber, H. I. Ali, and H. I. El Diwani. Synthesis, biological evaluation, and docking studies of new 2-furylbenzimidazoles as anti- angiogenic agents: Part II, Arch Pharm, 347(4):291-304, 2014.
Links: [doi:10.1002/Ardp.201300356] [show BibTeX] [show abstract]  x  @article{RN4, author = {Temirak, A. and Shaker, Y. M. and Ragab, F. A. F. and Ali, M. M. and Soliman, S. M. and Mortier, J. and Wolber, G. and Ali, H. I. and El Diwani, H. I.}, title = {Synthesis, biological evaluation, and docking studies of new 2-furylbenzimidazoles as anti- angiogenic agents: Part II}, journal = {Archiv der Pharmazie}, volume = {347}, number = {4}, pages = {291-304}, note = {Ae0wj Times Cited:0 Cited References Count:38}, abstract = {The 2-(5-methyl-2-furyl)-1H-benzimidazole moiety has shown promising activity against vascular endothelial growth factor (VEGF)-induced angiogenesis. In part I of this study, we have synthesized new analogs and tested their anti-angiogenic potentials. Here, we continue our previous study with different new analogs. Some compounds show promising cytotoxic activity against the human breast cancer cell line MCF-7, with IC50 in the range of 7.80-13.90 mu g/mL, and exhibited remarkable in vitro inhibition against VEGF in the MCF-7 cancer cell line, with 95-98% of inhibition in comparison to tamoxifen as reference (IC50: 8.00 mu g/mL, % of inhibition=98%). Additionally, a molecular docking study was carried out to gain insight into plausible binding modes and to understand the structure-activity relationships of the synthesized compounds.}, keywords = {application}, ISSN = {0365-6233}, DOI = {10.1002/Ardp.201300356}, url = {Go to ISI://WOS:000333686700008 http://onlinelibrary.wiley.com/store/10.1002/ardp.201300356/asset/ardp201300356.pdf?v= 1&t=i0dnk0o7&s=adf05599c316cb9a97e07a9131eb4f64f613102a}, year = {2014}, type = {Journal Article} }  x  Synthesis, biological evaluation, and docking studies of new 2-furylbenzimidazoles as anti- angiogenic agents: Part II

The 2-(5-methyl-2-furyl)-1H-benzimidazole moiety has shown promising activity against vascular endothelial growth factor (VEGF)-induced angiogenesis. In part I of this study, we have synthesized new analogs and tested their anti-angiogenic potentials. Here, we continue our previous study with different new analogs. Some compounds show promising cytotoxic activity against the human breast cancer cell line MCF-7, with IC50 in the range of 7.80-13.90 mu g/mL, and exhibited remarkable in vitro inhibition against VEGF in the MCF-7 cancer cell line, with 95-98% of inhibition in comparison to tamoxifen as reference (IC50: 8.00 mu g/mL, % of inhibition=98%). Additionally, a molecular docking study was carried out to gain insight into plausible binding modes and to understand the structure-activity relationships of the synthesized compounds.

[79]

C. D. Cadicamo, J. Mortier, G. Wolber, M. Hell, I. E. Heinrich, D. Michel, L. Semlin, U. Berger, H. C. Korting, H. D. Holtje, B. Koksch, and C. Borelli. Design, synthesis, inhibition studies, and molecular modeling of pepstatin analogues addressing different secreted aspartic proteinases of Candida albicans, Biochem Pharmacol, 85(7):881-887, 2013.
Links: [doi:10.1016/J.Bcp.2012.12.008] [show BibTeX] [show abstract]  x  @article{RN19, author = {Cadicamo, C. D. and Mortier, J. and Wolber, G. and Hell, M. and Heinrich, I. E. and Michel, D. and Semlin, L. and Berger, U. and Korting, H. C. and Holtje, H. D. and Koksch, B. and Borelli, C.}, title = {Design, synthesis, inhibition studies, and molecular modeling of pepstatin analogues addressing different secreted aspartic proteinases of Candida albicans}, journal = {Biochemical Pharmacology}, volume = {85}, number = {7}, pages = {881-887}, note = {110DO Times Cited:1 Cited References Count:39}, abstract = {The family of secreted aspartic proteinases is known as an important virulence factor of yeast infections by Candida albicans in particular, which is the most common fungal pathogen for humans with respect to systemic disease. Due to the continuing increase of drug resistant strains, these proteinases are currently considered as promising drug target candidates. Based on the known Sap2-substrate specificity data and X-ray analyses of Sap/inhibitor complexes, three libraries of inhibitors were designed and synthesized by modifying the structure of pepstatin A, a common non-selective aspartic proteinase inhibitor, at the P3, P2, or P2' position. These novel inhibitors showed high inhibitory potencies for the isoenzymes Sap1, Sap3, Sap5 and Sap6. Then, the affinity and selectivity of the peptide ligands were investigated by molecular modeling, highlighting new key structural information for the design of potent and selective anti-virulence agents targeting Candida albicans. (c) 2012 Elsevier Inc. All rights reserved.}, keywords = {anti-virulence agent peptidomimetic candidapeptidase secreted aspartic proteinases inhibition pepstatin candida albicans solid-phase synthesis crystal-structure in-vivo virulence expression proteases pharmacophores parapsilosis pathogenesis repository}, ISSN = {0006-2952}, DOI = {10.1016/J.Bcp.2012.12.008}, url = {Go to ISI://WOS:000316423000004 http://ac.els-cdn.com/S0006295212007940/1-s2.0-S0006295212007940-main.pdf?_tid= b5706d5e-4240-11e4-87eb-00000aab0f27&acdnat=1411380821_0911f281fa7759a5300962e9ca09acb7}, year = {2013}, type = {Journal Article} }  x  Design, synthesis, inhibition studies, and molecular modeling of pepstatin analogues addressing different secreted aspartic proteinases of Candida albicans

The family of secreted aspartic proteinases is known as an important virulence factor of yeast infections by Candida albicans in particular, which is the most common fungal pathogen for humans with respect to systemic disease. Due to the continuing increase of drug resistant strains, these proteinases are currently considered as promising drug target candidates. Based on the known Sap2-substrate specificity data and X-ray analyses of Sap/inhibitor complexes, three libraries of inhibitors were designed and synthesized by modifying the structure of pepstatin A, a common non-selective aspartic proteinase inhibitor, at the P3, P2, or P2' position. These novel inhibitors showed high inhibitory potencies for the isoenzymes Sap1, Sap3, Sap5 and Sap6. Then, the affinity and selectivity of the peptide ligands were investigated by molecular modeling, highlighting new key structural information for the design of potent and selective anti-virulence agents targeting Candida albicans. (c) 2012 Elsevier Inc. All rights reserved.

[78]

K. N. de Oliveira, V. Andermark, S. von Grafenstein, L. A. Onambele, G. Dahl, R. Rubbiani, G. Wolber, C. Gabbiani, L. Messori, A. Prokop, and I. Ott. Butyltin(IV) benzoates: Inhibition of thioredoxin reductase, tumor cell growth inhibition, and interactions with proteins, ChemMedChem, 8(2):256-264, 2013.
Links: [doi:10.1002/Cmdc.201200505] [show BibTeX] [show abstract]  x  @article{RN20, author = {de Oliveira, K. N. and Andermark, V. and von Grafenstein, S. and Onambele, L. A. and Dahl, G. and Rubbiani, R. and Wolber, G. and Gabbiani, C. and Messori, L. and Prokop, A. and Ott, I.}, title = {Butyltin(IV) benzoates: Inhibition of thioredoxin reductase, tumor cell growth inhibition, and interactions with proteins}, journal = {Chemmedchem}, volume = {8}, number = {2}, pages = {256-264}, note = {079LU Times Cited:3 Cited References Count:59}, abstract = {Thioredoxin reductase (TrxR) is overexpressed in cancer cells and is therefore a putative cancer target. Inhibition of this enzyme is considered an important strategy for the development of new chemotherapeutic agents with a specific mechanism of action. Organotin compounds have been described as experimental antitumor agents, yet their mechanism of action remains largely unknown. Based on the outcome of a virtual screening study, various di- and tri-n-butyltin(IV) carboxylates were synthesized, and their biological properties were evaluated. All synthesized compounds were able to inhibit TrxR selectively within the micromolar range and showed potent antitumor activity against HT-29 and MCF-7 cancer cell lines. Moreover, tin(IV) organometallics were