Toxicological importance of CYP3A4 catalysis and inhibition

CYP3A4 催化和抑制的毒理学重要性

• 批准号: 10358992
• 负责人: Irina F Sevrioukova
• 金额: $ 56.16万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2026-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10358992
• 关键词: 3-Dimensional; Active Sites; Address; Affect; Affinity; Allosteric Regulation; Area; Basic Science; Behavior; Binding; Biochemical; Biological Availability; CYP3A4 gene; Carcinogens; Catalysis; Characteristics; Chemicals; Clinical; Comparative Study; Complex; Consumption; Crystallization; Data; Development; Docking; Drug Interactions; Drug Stability; Drug toxicity; Environmental Pollutants; Enzymes; Failure; Flavonoids; Funding; Generations; Goals; HIV Infections; HIV Protease Inhibitors; Health; Hepatitis C; Herbicides; Heterogeneity; Human; Insecticides; Investigation; Ketoconazole; Kinetics; Knowledge; Label; Lead; Ligand Binding; Ligands; Liver Microsomes; Maps; Metabolic; Metabolism; Modeling; Modification; Molecular; Molecular Conformation; NADP; Organ Transplantation; Peripheral; Pesticides; Pharmaceutical Preparations; Pharmacologic Substance; Phenotype; Plasma; Principal Investigator; Process; Proteins; Reaction; Research; Ritonavir; Role; Site; Structure; System; Testing; Therapeutic; Toxic effect; Toxicology; Translational Research; Transplant Recipients; Xenobiotic Metabolism; Xenobiotics; analog; base; clinically relevant; design; dietary; drug candidate; drug development; drug efficacy; drug metabolism; improved; in silico; inhibitor; insight; novel; oxidation; pharmacophore; programs; rational design; reconstitution; stoichiometry; structural biology; therapeutic effectiveness; tool

Program Director/Principal Investigator (Sevrioukova, Irina F.): Project Summary Human cytochrome P450 3A4 (CYP3A4) is the major and most clinically relevant drug-metabolizing enzyme, notoriously known for its extreme substrate promiscuity and allosteric behavior. Drugs and other xenobiotics can also stimulate and inhibit CYP3A4 activity, which frequently leads to undesired drug-drug interactions (DDIs), chemical toxicity and therapeutic failures. Despite extensive investigations, the CYP3A4 inhibitory and activation mechanisms remain incompletely understood. This proposal centers on using structural biology approaches to address key issues in both areas of CYP3A4 research. Aim 1 is set to investigate the CYP3A4 inhibitory mechanism via rational structure-based design of analogues of ritonavir, an HIV protease inhibitor whose ability to potently inhibit CYP3A4 was purely coincidental. We will identify structural determinants required for potent inhibition by rationally designing and investigating structure-activity relations of ritonavir-like compounds and, based on our findings, build a 3D-pharmacophore model for a potent CYP3A4-specific inhibitor that can be used for early prediction/elimination of the inhibitory potential in drug candidates and for development of more effective pharmacoenhancers. Aim 2 will utilize an integrated biochemical, chemical labeling, structural and computational approach to investigate the CYP3A4 substrate binding cooperativity and allosterism. Our recent structural findings confirmed the importance of the previously mapped peripheral area and identified three novel inner sites that could serve for substrate/effector docking. We will evaluate the role and relative importance of these areas by assessing how their modification/disruption affects CYP3A4 conformation, substrate binding cooperativity, stoichiometry and metabolism. The research outlined in this proposal is important from both the basic and translational science perspectives, because it will fill the knowledge gaps and provide fundamental insights into plasticity and adaptability of CYP3A4 to structurally diverse ligands, clarify molecular mechanisms underlying the complex ligand binding behavior and oxidative kinetics, and help develop better tools for in silico prediction of protein-ligand contacts, metabolic stability and DDI potential in drug candidates to improve their efficacy and reduce off-target effects. OMB No. 0925-0001/0002 (Rev. 08/12 Approved Through 8/31/2015) Page Continuation Format Page

项目主任/首席研究员（Sevrioukova，Irina F.）： 项目概要 人细胞色素 P450 3A4 (CYP3A4) 是主要且与临床最相关的药物代谢酶， 以其极端的底物混杂性和变构行为而闻名。药物和其他外源物质 还可以刺激和抑制 CYP3A4 活性，这经常导致不良的药物相互作用 （DDI）、化学毒性和治疗失败。尽管进行了广泛的研究，CYP3A4 抑制和 激活机制仍不完全清楚。该提案的重点是使用结构生物学 解决 CYP3A4 研究两个领域关键问题的方法。目标 1 旨在研究 CYP3A4 通过基于合理结构的利托那韦类似物（一种 HIV 蛋白酶抑制剂）设计的抑制机制 其有效抑制 CYP3A4 的能力纯属巧合。我们将确定结构性决定因素 通过合理设计和研究利托那韦样的构效关系来实现有效的抑制 化合物，并根据我们的发现，为有效的 CYP3A4 特异性构建 3D 药效团模型 抑制剂，可用于早期预测/消除候选药物的抑制潜力以及 开发更有效的药物增强剂。目标 2 将利用综合生化、化学 标记、结构和计算方法来研究 CYP3A4 底物结合协同性和 变构现象。我们最近的结构发现证实了先前绘制的外围区域的重要性 并确定了三个可用于底物/效应器对接的新颖内部位点。我们将评估该角色 通过评估这些区域的修改/破坏如何影响 CYP3A4 来确定这些区域的相对重要性 构象、底物结合协同性、化学计量和代谢。本文概述的研究 从基础科学和转化科学的角度来看，该提案都很重要，因为它将填补 知识差距并为 CYP3A4 的可塑性和适应性提供基本见解 不同的配体，阐明复杂配体结合行为和氧化的分子机制 动力学，并帮助开发更好的工具来计算机预测蛋白质-配体接触、代谢稳定性和 DDI 在候选药物中具有提高疗效并减少脱靶效应的潜力。 OMB 编号 0925-0001/0002（修订版 08/12 已批准至 8/31/2015） 页面延续格式页面