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Wang D, Wu H, Zhang Q, Zhou X, An Y, Zhao A, Chong J, Wang S, Wang F, Yang J, Dai D, Chen H. Optimisation of warfarin-dosing algorithms for Han Chinese patients with CYP2C9*13 variants. Eur J Clin Pharmacol 2023; 79:1315-1320. [PMID: 37458773 DOI: 10.1007/s00228-023-03540-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Accepted: 07/13/2023] [Indexed: 09/16/2023]
Abstract
BACKGROUND Existing pharmacogenetic algorithms cannot fully explain warfarin dose variability in all patients. CYP2C9*13 is an important allelic variant in the Han Chinese population. However, adjustment of warfarin dosing in CYP2C9*13 variant carriers remains unclear. To the best of our knowledge, this study is the first to assess the effects of adjusting warfarin dosages in Han Chinese patients harbouring CYP2C9*13 variants. METHODS In total, 971 warfarin-treated Han Chinese patients with atrial fibrillation were enrolled in this study. Clinical data were collected, and CYP2C9*2, *3, *13 and VKORC1-1639 G > A variants were genotyped. We quantitatively analysed the effect of CYP2C9*13 on warfarin maintenance dose and provided multiplicative adjustments for CYP2C9*13 using validated pharmacogenetic algorithms. RESULTS Approximately 0.6% of the Han Chinese population carried CYP2C9*13 variant, and the genotype frequency was between those of CYP2C9*2 and CYP2C9*3. The warfarin maintenance doses were significantly reduced in CYP2C9*13 carriers. When CYP2C9*13 variants were not considered, the pharmacogenetic algorithms overestimated warfarin maintenance doses by 1.03-1.16 mg/d on average. The actual warfarin dose in CYP2C9*13 variant carriers was approximately 40% lower than the algorithm-predicted dose. Adjusting the warfarin-dosing algorithm according to the CYP2C9*13 allele could reduce the dose prediction error. CONCLUSION Our study showed that the algorithm-predicted doses should be lowered for CYP2C9*13 carriers. Inclusion of the CYP2C9*13 variant in the warfarin-dosing algorithm tends to predict the warfarin maintenance dose more accurately and improves the efficacy and safety of warfarin administration in Han Chinese patients.
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Affiliation(s)
- Dongxu Wang
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
- Fuwai Hospital, Arrhythmia Center, Chinese Academy of Medical Sciences, National Center for Cardiovascular Diseases, 100037, Beijing, China
| | - Hualan Wu
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Qing Zhang
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Xiaoyue Zhou
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Yang An
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Anxu Zhao
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Jia Chong
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Shuanghu Wang
- Laboratory of Clinical Pharmacy, The Sixth Affiliated Hospital of Wenzhou Medical University, The People's Hospital of Lishui, Lishui, 323020, China
| | - Fang Wang
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Jiefu Yang
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Dapeng Dai
- The Key Laboratory of Geriatrics, Beijing Institute of Geriatrics, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Hao Chen
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China.
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Parray ZA, Ahmad F, Chaudhary AA, Rudayni HA, Al-Zharani M, Hassan MI, Islam A. Size-Dependent Interplay of Volume Exclusion Versus Soft Interactions: Cytochrome c in Macromolecular Crowded Environment. Front Mol Biosci 2022; 9:849683. [PMID: 35693552 PMCID: PMC9174945 DOI: 10.3389/fmolb.2022.849683] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/28/2022] [Indexed: 12/03/2022] Open
Abstract
Even though there are a great number of possible conformational states, how a protein generated as a linear unfolded polypeptide efficiently folds into its physiologically active form remained a fascinating and unanswered enigma inside crowded conditions of cells. In this study, various spectroscopic techniques have been exploited to know and understand the effect and mechanism of action of two different sizes of polyethylene glycols, or PEGs (molecular mass ∼10 and ∼20 kilo Daltons, kDa), on cytochrome c (cyt c). The outcomes showed that small size of the PEG leads to perturbation of the protein structure, and conversely, large size of the PEG has stabilizing effect on cyt c. Moreover, binding measurements showed that small size of PEG interacts strongly via soft interactions compared to the larger size of PEG, the latter being governed more by excluded volume effect or preferential exclusion from the protein. Overall, this finding suggests that conformations of protein may be influenced in cellular crowded conditions via interactions which depend upon the size of molecule in the environment. This study proposes that both volume exclusion and soft (chemical) interactions governs the protein’s conformation and functional activities. The cellular environment’s internal architecture as evident from crowder size and shape in this study has a significant role.
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Affiliation(s)
- Zahoor Ahmad Parray
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
- Department of Chemistry, Indian Institute of Technology Delhi, New Delhi, India
| | - Faizan Ahmad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
- Department of Biochemistry, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, India
| | - Anis Ahmad Chaudhary
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Saudi Arabia
| | - Hassan Ahmad Rudayni
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Saudi Arabia
| | - Mohammed Al-Zharani
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Saudi Arabia
| | - Md. Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
- *Correspondence: Asimul Islam,
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Wang D, Dai DP, Wu H, Chong J, Lü Y, Yin R, Zhao X, Zhao A, Yang J, Chen H. Effects of rare CYP2C9 alleles on stable warfarin doses in Chinese Han patients with atrial fibrillation. Pharmacogenomics 2020; 21:1021-1031. [PMID: 32893731 DOI: 10.2217/pgs-2020-0051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Aim: Gene polymorphisms are critical in warfarin dosing variation. Here, the role of rare CYP2C9 alleles on warfarin doses in Chinese Han patients was investigated. Methods: A retrospective study recruited 681 warfarin treated atrial fibrillation patients. The genetic and clinical data were collected. Dose-related variables were selected by univariate analyses and the warfarin-dosing algorithm was derived by multivariate regression analysis. Results: Three rare CYP2C9 alleles (CYP2C9*13, *16 and *60) were associated with lower stable doses. Inclusion of the rare CYP2C9 alleles in the prediction model added an extra 3.7% warfarin dose predictive power. Conclusion: CYP2C9*13, *16 and *60 was associated with lower stable warfarin doses in Chinese patients. The algorithm including rare CYP2C9 alleles tends to more accurately predict stable warfarin doses.
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Affiliation(s)
- Dongxu Wang
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Da-Peng Dai
- The Key Laboratory of Geriatrics, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Hualan Wu
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Jia Chong
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - You Lü
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Ruoyun Yin
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Xinlong Zhao
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Anxu Zhao
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Jiefu Yang
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
| | - Hao Chen
- Cardiovascular Department, Beijing Hospital, National Centre of Gerontology, Beijing, 100730, China
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Fine J, Konc J, Samudrala R, Chopra G. CANDOCK: Chemical Atomic Network-Based Hierarchical Flexible Docking Algorithm Using Generalized Statistical Potentials. J Chem Inf Model 2020; 60:1509-1527. [PMID: 32069042 DOI: 10.1021/acs.jcim.9b00686] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Small-molecule docking has proven to be invaluable for drug design and discovery. However, existing docking methods have several limitations such as improper treatment of the interactions of essential components in the chemical environment of the binding pocket (e.g., cofactors, metal ions, etc.), incomplete sampling of chemically relevant ligand conformational space, and the inability to consistently correlate docking scores of the best binding pose with experimental binding affinities. We present CANDOCK, a novel docking algorithm, that utilizes a hierarchical approach to reconstruct ligands from an atomic grid using graph theory and generalized statistical potential functions to sample biologically relevant ligand conformations. Our algorithm accounts for protein flexibility, solvent, metal ions, and cofactor interactions in the binding pocket that are traditionally ignored by current methods. We evaluate the algorithm on the PDBbind, Astex, and PINC proteins to show its ability to reproduce the binding mode of the ligands that is independent of the initial ligand conformation in these benchmarks. Finally, we identify the best selector and ranker potential functions such that the statistical score of the best selected docked pose correlates with the experimental binding affinities of the ligands for any given protein target. Our results indicate that CANDOCK is a generalized flexible docking method that addresses several limitations of current docking methods by considering all interactions in the chemical environment of a binding pocket for correlating the best-docked pose with biological activity. CANDOCK along with all structures and scripts used for benchmarking is available at https://github.com/chopralab/candock_benchmark.
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Affiliation(s)
- Jonathan Fine
- Department of Chemistry, Purdue University, 720 Clinic Drive, West Lafayette, Indiana 47906, United States
| | - Janez Konc
- National Institute of Chemistry, Hajdrihova 19, SI-1000, Ljubljana, Slovenia
| | - Ram Samudrala
- Department of Biomedical Informatics, SUNY, Buffalo, New York 14260, United States
| | - Gaurav Chopra
- Department of Chemistry, Purdue University, 720 Clinic Drive, West Lafayette, Indiana 47906, United States.,Purdue Institute for Drug Discovery, West Lafayette, Indiana 47907, United States.,Purdue Center for Cancer Research, West Lafayette, Indiana 47907, United States.,Purdue Institute for Inflammation, Immunology and Infectious Disease, West Lafayette, Indiana 47907, United States.,Purdue Institute for Integrative Neuroscience, West Lafayette, Indiana 47907, United States.,Integrative Data Science Initiative, West Lafayette, Indiana 47907, United States
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5
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Mehla K, Ramana J. Molecular Dynamics Simulations of Quinolone Resistance-Associated T86I and P104S Mutations in Campylobacter jejunigyrA: Unraveling Structural Repercussions. Microb Drug Resist 2018; 24:232-243. [DOI: 10.1089/mdr.2017.0020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Kusum Mehla
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
| | - Jayashree Ramana
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, India
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Daly AK, Rettie AE, Fowler DM, Miners JO. Pharmacogenomics of CYP2C9: Functional and Clinical Considerations. J Pers Med 2017; 8:E1. [PMID: 29283396 PMCID: PMC5872075 DOI: 10.3390/jpm8010001] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/18/2017] [Accepted: 12/20/2017] [Indexed: 02/07/2023] Open
Abstract
CYP2C9 is the most abundant CYP2C subfamily enzyme in human liver and the most important contributor from this subfamily to drug metabolism. Polymorphisms resulting in decreased enzyme activity are common in the CYP2C9 gene and this, combined with narrow therapeutic indices for several key drug substrates, results in some important issues relating to drug safety and efficacy. CYP2C9 substrate selectivity is detailed and, based on crystal structures for the enzyme, we describe how CYP2C9 catalyzes these reactions. Factors relevant to clinical response to CYP2C9 substrates including inhibition, induction and genetic polymorphism are discussed in detail. In particular, we consider the issue of ethnic variation in pattern and frequency of genetic polymorphisms and clinical implications. Warfarin is the most well studied CYP2C9 substrate; recent work on use of dosing algorithms that include CYP2C9 genotype to improve patient safety during initiation of warfarin dosing are reviewed and prospects for their clinical implementation considered. Finally, we discuss a novel approach to cataloging the functional capabilities of rare 'variants of uncertain significance', which are increasingly detected as more exome and genome sequencing of diverse populations is conducted.
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Affiliation(s)
- Ann K Daly
- Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
| | - Allan E Rettie
- Department of Medicinal Chemistry, University of Washington, Seattle, WA 98195, USA.
| | - Douglas M Fowler
- Department of Genome Sciences and Department of Bioengineering, University of Washington, Seattle, WA 98195, USA.
| | - John O Miners
- Department of Clinical Pharmacology, Flinders University School of Medicine, Adelaide 5042, Australia.
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Hypermethylation of brain natriuretic peptide gene is associated with the risk of rheumatic heart disease. Biosci Rep 2017; 37:BSR20160408. [PMID: 27920275 PMCID: PMC5240589 DOI: 10.1042/bsr20160408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/15/2016] [Accepted: 12/05/2016] [Indexed: 01/09/2023] Open
Abstract
To investigate the contribution of brain natriuretic peptide (BNP) promoter DNA methylation to the risk of rheumatic heart disease (RHD) and the influence of warfarin anticoagulant therapy on BNP methylation levels for RHD patients after surgery. BNP methylation levels were determined by bisulfite pyrosequencing from plasma samples of RHD patients compared with healthy controls. Several factors influencing the RHD patients were included like age, smoking and cholesterol levels. A fragment of five CG sites (CpG1–5) in the promoter region of BNP gene was measured. BNP gene hypermethylation was found in CpG4 and CpG5 in RHD patients compared with non-RHD controls. A significant difference was also observed between RHD patients with long-term administration of warfarin and RHD patients who had recently undergone an operation. Moreover, single CpG4 and CpG5 analysis revealed a significant increase in methylation levels in men. BNP gene body hypermethylation is associated with the risk of RHD, and also influenced by the warfarin anticoagulant therapy of RHD patients after surgery, which could represent novel and promising targets for therapeutic development.
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Nair PC, McKinnon RA, Miners JO. Cytochrome P450 structure–function: insights from molecular dynamics simulations. Drug Metab Rev 2016; 48:434-52. [DOI: 10.1080/03602532.2016.1178771] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Nakamura M, Wang YQ, Wang C, Oh D, Yin WH, Kimura T, Miyazaki K, Abe K, Mercuri M, Lee LH, Segers A, Büller H. Efficacy and safety of edoxaban for treatment of venous thromboembolism: a subanalysis of East Asian patients in the Hokusai-VTE trial. J Thromb Haemost 2015; 13:1606-14. [PMID: 26179767 DOI: 10.1111/jth.13055] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 07/04/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND Direct oral anticoagulants have been evaluated for their efficacy and safety in the treatment of venous thromboembolism (VTE), which comprises deep vein thrombosis and pulmonary embolism. The randomized, double-blind Hokusai-VTE trial demonstrated that 60 mg of edoxaban once daily following initial heparin treatment is non-inferior to heparin overlapped with and followed by warfarin for the treatment of VTE, and is associated with significantly fewer bleeding events. OBJECTIVES To assess the efficacy and safety of edoxaban versus warfarin among East Asian patients enrolled in the Hokusai-VTE trial. PATIENTS/METHODS The Hokusai-VTE trial enrolled 8292 patients from 439 centers worldwide, including 1109 patients from Japan, China, Korea, and Taiwan. The primary efficacy and safety outcomes were symptomatic recurrent VTE and clinically relevant bleeding, respectively. RESULTS In the overall East Asian population, the primary efficacy outcome of symptomatic recurrent VTE occurred in 16 of 563 (2.8%) patients in the edoxaban group versus 24 of 538 (4.5%) patients in the warfarin group (hazard ratio [HR] 0.64; 95% confidence interval [CI] 0.34-1.19; P = 0.1601). The primary safety outcome of clinically relevant bleeding occurred in 56 of 563 (9.9%) patients in the edoxaban group versus 93 of 538 (17.3%) patients in the warfarin group (HR 0.56; 95% CI 0.40-0.78; P < 0.001). CONCLUSIONS Edoxaban is an effective and safer alternative to warfarin in East Asian patients with acute VTE who require anticoagulant therapy, consistent with overall study findings from the Hokusai-VTE trial.
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Affiliation(s)
- M Nakamura
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - Y Q Wang
- Zhongshan Hospital, Fudan University, Shanghai, China
| | - C Wang
- National Clinical Research Center of Respiratory Diseases, Capital Medical University, Beijing, China
- Department of Respiratory Medicine, Capital Medical University, Beijing, China
- China-Japan Friendship Hospital, Beijing, China
| | - D Oh
- CHA Bundang Medical Center, CHA University, Gyeongghi-do, South Korea
| | - W-H Yin
- Heart Center, Cheng Hsin General Hospital, Taipei, Taiwan
- Faculty of Medicine, National Yang Ming University, Taipei, Taiwan
| | - T Kimura
- Clinical Planning Department, Daiichi Sankyo Co. Ltd, Tokyo, Japan
| | - K Miyazaki
- Asia Development Department, Daiichi Sankyo Co. Ltd, Tokyo, Japan
| | - K Abe
- Clinical Data & Biostatistics Department, Daiichi Sankyo Co. Ltd, Tokyo, Japan
| | - M Mercuri
- Clinical Development Department, Daiichi Sankyo Pharma Development, Edison, NJ, USA
| | - L H Lee
- Department of Hematology, Singapore General Hospital, Singapore, Singapore
| | - A Segers
- ITREAS, Amsterdam, the Netherlands
| | - H Büller
- Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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Pavani A, Naushad SM, Stanley BA, Kamakshi RG, Abinaya K, Amaresh Rao M, Uma A, Kutala VK. Mechanistic insights into the effect of CYP2C9*2 and CYP2C9*3 variants on the 7-hydroxylation of warfarin. Pharmacogenomics 2015; 16:393-400. [PMID: 25823787 DOI: 10.2217/pgs.14.185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
AIM To evaluate the impact of CYP2C9*2 and CYP2C9*3 variants on binding and hydroxylation of warfarin. MATERIALS & METHODS Multiple linear regression model of warfarin pharmacokinetics was developed from the dataset of patients (n = 199). Pymol based in silico models were developed for the genetic variants. RESULTS CYP2C9*2 and CYP2C9*3 variants exhibited high warfarin/7-hydroxywarfarin (multiple linear regression model), dose-dependent disruption of hydrogen bonds with warfarin, dose-dependent increase in the distance between C7 of S-warfarin and Fe-O of CYP2C9, dose-dependent decrease in the glide scores (in silico). CONCLUSION CYP2C9*2 and CYP2C9*3 variants result in disruption of hydrogen bonding interactions with warfarin and longer distance between C7 and Fe-O thus impairing warfarin 7-hydroxylation due to lower binding affinity of warfarin. Original submitted 7 May 2014; Revision submitted 30 October 2014.
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Affiliation(s)
- Addepalli Pavani
- Department of Clinical Pharmacology & Therapeutics, Nizam's Institute of Medical Sciences, Punjagutta, Hyderabad, India
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de Waal PW, Sunden KF, Furge LL. Molecular dynamics of CYP2D6 polymorphisms in the absence and presence of a mechanism-based inactivator reveals changes in local flexibility and dominant substrate access channels. PLoS One 2014; 9:e108607. [PMID: 25286176 PMCID: PMC4186923 DOI: 10.1371/journal.pone.0108607] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Accepted: 09/01/2014] [Indexed: 11/18/2022] Open
Abstract
Cytochrome P450 enzymes (CYPs) represent an important enzyme superfamily involved in metabolism of many endogenous and exogenous small molecules. CYP2D6 is responsible for ∼ 15% of CYP-mediated drug metabolism and exhibits large phenotypic diversity within CYPs with over 100 different allelic variants. Many of these variants lead to functional changes in enzyme activity and substrate selectivity. Herein, a molecular dynamics comparative analysis of four different variants of CYP2D6 was performed. The comparative analysis included simulations with and without SCH 66712, a ligand that is also a mechanism-based inactivator, in order to investigate the possible structural basis of CYP2D6 inactivation. Analysis of protein stability highlighted significantly altered flexibility in both proximal and distal residues from the variant residues. In the absence of SCH 66712, *34, *17-2, and *17-3 displayed more flexibility than *1, and *53 displayed more rigidity. SCH 66712 binding reversed flexibility in *17-2 and *17-3, through *53 remained largely rigid. Throughout simulations with docked SCH 66712, ligand orientation within the heme-binding pocket was consistent with previously identified sites of metabolism and measured binding energies. Subsequent tunnel analysis of substrate access, egress, and solvent channels displayed varied bottle-neck radii. Taken together, our results indicate that SCH 66712 should inactivate these allelic variants, although varied flexibility and substrate binding-pocket accessibility may alter its interaction abilities.
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Affiliation(s)
- Parker W. de Waal
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan, United States of America
| | - Kyle F. Sunden
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan, United States of America
| | - Laura Lowe Furge
- Department of Chemistry, Kalamazoo College, Kalamazoo, Michigan, United States of America
- * E-mail:
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