Abstract：
Unknown interactions between drugs remain the limiting factor for clinical application of drugs, and the induction and inhibition of drug-metabolizing CYP enzymes are considered the key to examining the drug-drug interaction (DDI). In this study, using human HepaRG cells as an in vitro model system, we analyzed the potential DDI based on the expression levels of CYP3A4 and CYP1A2. Rifampicin and omeprazole, the potent inducers for CYP3A4 and CYP1A2, respectively, induce expression of the corresponding CYP enzymes at both the mRNA and protein levels. We noticed that, in addition to inducing CYP1A2, omeprazole induced CYP3A4 mRNA expression in HepaRG cells. However, unexpectedly, CYP3A4 protein expression levels were not increased after omeprazole treatment. Concurrent administration of rifampicin and omeprazole showed an inhibitory effect of omeprazole on the CYP3A4 protein expression induced by rifampicin, while its mRNA induction remained intact. Cycloheximide chase assay revealed increased CYP3A4 protein degradation in the cells exposed to omeprazole. The data presented here suggest the potential importance of broadening the current DDI examination beyond conventional transcriptional induction and enzyme-activity inhibition tests to include post-translational regulation analysis of CYP enzyme expression.
摘要：
药物之间未知的相互作用仍然是药物临床应用的限制因素，药物代谢CYP酶的诱导和抑制被认为是检查药物-药物相互作用（DDI）的关键。在这项研究中,使用人HepaRG细胞作为体外模型系统，我们根据CYP3A4和CYP1A2的表达水平分析了潜在的DDI。利福平和奥美拉唑，CYP3A4和CYP1A2的有效诱导剂，在mRNA和蛋白质水平诱导相应CYP酶的表达。我们注意到,除诱导CYP1A2外，奥美拉唑还诱导HepaRG细胞中CYP3A4mRNA的表达。然而,出乎意料的是,奥美拉唑治疗后CYP3A4蛋白表达水平没有增加。同时服用利福平和奥美拉唑对利福平诱导的CYP3A4蛋白表达有抑制作用，而其mRNA诱导保持完整。环己酰亚胺追踪测定显示暴露于奥美拉唑的细胞中CYP3A4蛋白降解增加。此处提供的数据表明，将当前的DDI检查范围扩大到常规的转录诱导和酶活性抑制测试之外，以包括CYP酶表达的翻译后调节分析的潜在重要性。
