Toward a systems approach to the human cytochrome P450 ensemble: interactions between CYP2D6 and CYP2E1 and their functional consequences.
Toward a systems approach to the human cytochrome P450 ensemble: interactions between CYP2D6 and CYP2E1 and their functional consequences.
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DOI：
10.1042/bcj20170543
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发表时间：
2017-10-10
期刊：
影响因子：
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通讯作者：
Jones JP
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文献类型：
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作者：
Davydov DR;Davydova NY;Rodgers JT;Rushmore TH;Jones JP
人类药物代谢细胞色素 P450 之间通过其关联进行的功能串扰是一个日益重要的话题。在这里，我们研究了人类 CYP2D6（精神活性药物的主要代谢者）与最常见的人类 P450 酶之一（乙醇诱导型 CYP2E1）的相互作用。 P450-P450 相互作用的检测是通过掺入人肝微粒体的标记蛋白与含有 NADPH-细胞色素 P450 还原酶的昆虫细胞微粒体之间的发光共振能量转移 (LRET) 来完成的。 CYP2D6 在微粒体膜中形成寡聚体的潜力是迄今为止研究的人类细胞色素 P450 中观察到的最高潜力之一。我们还观察到 CYP2D6 与 CYP2E1 和 CYP3A4 形成异聚复合物，并发现 MDMA（一种由 CYP2D6 代谢的广泛滥用药物）对这些相互作用有显着调节作用。我们的结果表明，CYP2D6 和 CYP2E1 的结合导致其催化特性发生了很大的改变。特别是，我们证明，含有共掺入的 CYP2D6 和 CYP2E1 与 CYP2D6 特异性底物的微粒体的预孵育会导致 CYP2D6 的相当大的时间依赖性激活，这可能是通过缓慢的底物诱导的 CYP2E1-CYP2D6 异低聚物重组而发生的。此外，我们证明，CYP2E1 和 CYP2D6 之间异聚复合物的形成通过减少过氧化物生成途径的电子泄漏，影响 CYP2D6 无效循环和底物氧化的化学计量。我们的结果进一步强调了 P450-P450 相互作用在人类药物代谢整体调节串扰中的作用，并表明 CYP2E1 与 CYP2D6 相互作用在酒精-药物相互作用的药理学重要实例中的作用。
Functional cross-talk among human drug-metabolizing cytochromes P450 through their association is a topic of emerging importance. Here we studied the interactions of human CYP2D6, a major metabolizer of psychoactive drugs, with one of the most prevalent human P450 enzymes, ethanol-inducible CYP2E1. Detection of P450-P450 interactions was accomplished through luminescence resonance energy transfer (LRET) between labeled proteins incorporated into human liver microsomes and the microsomes of insect cells containing NADPH-cytochrome P450 reductase. The potential of CYP2D6 to form oligomers in the microsomal membrane is among the highest observed with human cytochromes P450 studied up to date. We also observed the formation of heteromeric complexes of CYP2D6 with CYP2E1 and CYP3A4, and found a significant modulation of these interactions by MDMA, a widespread drug of abuse metabolized by CYP2D6. Our results demonstrate an ample alteration of the catalytic properties of CYP2D6 and CYP2E1 caused by their association. In particular, we demonstrated that pre-incubation of microsomes containing co-incorporated CYP2D6 and CYP2E1 with CYP2D6-specific substrates resulted in considerable time-dependent activation of CYP2D6, which presumably occurs via a slow substrate-induced reorganization of CYP2E1-CYP2D6 heterooligomers. Furthermore, we demonstrated that the formation of heteromeric complexes between CYP2E1 and CYP2D6 affects the stoichiometry of futile cycling and substrate oxidation by CYP2D6 by means of decreasing the electron leakage through the peroxide-generating pathways. Our results further emphasize the role of P450-P450 interactions in regulatory cross-talk in human drug-metabolizing ensemble and suggest a role of interactions of CYP2E1 with CYP2D6 in pharmacologically important instances of alcohol-drug interactions.