论文部分内容阅读
目的:探讨3种中药成分(延胡索乙素、甲基莲心碱、三七总皂苷)对CYP3A4酶代谢活性的影响,以了解中药与CYP3A4酶底物联合用药时可能产生的相互作用。方法:采用超高速离心法制备大鼠肝脏微粒体,建立体外肝脏微粒体混合酶代谢体系。以睾丸酮作为底物探针,用HPLC建立检测CYP3A4酶代谢活性的方法,分别考察体外代谢体系的最适宜底物浓度、代谢时间、pH、孵育温度以及磷酸盐浓度。在确定的条件下,将3种中药成分稀释成不同浓度,分别与睾丸酮共同孵育于肝微粒体代谢体系中,测定在有或无中药成分存在下代谢产物6β-羟基睾丸酮的产生量,以评估中药成分对CYP3A4酶代谢的影响。结果:在肝微粒体孵育体系中,睾丸酮代谢为6β-羟基睾丸酮最适宜的体外代谢条件为底物浓度200μmol.L-1,代谢时间3.5 h,pH 7.0,孵育温度37℃,磷酸盐终浓度0.1 mol.L-1。延胡索乙素和三七总皂苷均对CYP3A4酶的抑制作用较弱,IC50>100μmol.L-1,甲基莲心碱有一定的抑制作用,IC50为(47.5±2.3)μmol.L-1。结论:延胡索乙素和三七总皂苷对CYP3A4酶代谢无明显影响,提示这2种中药成分与CYP3A4酶底物之间的相互作用较低,甲基莲心碱有可能会产生微弱的药物相互作用。
OBJECTIVE: To investigate the effects of three traditional Chinese medicine ingredients (tetrahydropalmatine, neferine and saponins of Panax notoginseng) on CYP3A4 metabolic activity in order to understand the possible interaction of CYP3A4 enzyme and traditional Chinese medicine. Methods: The rat liver microsomes were prepared by ultra-high speed centrifugation and the in vitro hepatic microsomal mixed enzyme metabolic system was established. Using testosterone as a substrate probe, the method of detecting the metabolic activity of CYP3A4 enzyme was established by HPLC, and the optimal substrate concentration, metabolic time, pH, incubation temperature and phosphate concentration of the in vitro metabolic system were respectively investigated. Under certain conditions, three kinds of traditional Chinese medicine ingredients were diluted into different concentrations and incubated with testosterone respectively in the microsomal metabolic system of liver microsomes to determine the amount of 6β-hydroxytestosterone metabolites in the presence of or without traditional Chinese medicine components to assess Effect of Chinese Herbal Medicine on CYP3A4 Enzyme Metabolism. Results: In liver microsomal incubation system, the most suitable in vitro metabolic conditions of testosterone metabolism were 6β-hydroxytestosterone: substrate concentration 200 μmol·L-1, metabolic time 3.5 h, pH 7.0, incubation temperature 37 ℃, final phosphate concentration 0.1 mol.L-1. Tetrahydropalmatine and notoginsenoside all had weaker inhibitory effect on CYP3A4. IC50> 100μmol.L-1 and neferine had some inhibitory effects, IC50 was (47.5 ± 2.3) μmol.L-1. CONCLUSION: Tetrahydropalmatine and notoginsenoside have no significant effect on the CYP3A4 enzyme metabolism, suggesting that the interaction between the two traditional Chinese medicines and the CYP3A4 enzyme substrate is low, and neferine may produce weak drug interactions .