论文部分内容阅读
目的对紫草素的立体异构单体阿卡宁的氧葡萄糖醛酸代谢通路进行研究和表征。方法采用液相色谱和质谱联用方法检测阿卡宁和其葡萄糖醛酸化代谢产物;将阿卡宁在人肝微粒体(HLM)、人肾微粒体(HKM)以及重组人类葡萄糖醛酸转移酶(UGT)中孵育,观察代谢轮廓、筛选参与催化的重组单酶、考察酶动力学;通过相关性分析以及化学抑制实验阐明UGT单酶对阿卡宁的选择性。结果阿卡宁在含尿苷5’-二磷酸葡萄糖醛酸(UDPGA)的HLM孵育中,可以检测到1个UGT代谢产物。UGT单酶筛选发现UGT1A9高选择性催化阿卡宁。酶动力学研究显示在HLM、HKM和UGT1A9中阿卡宁的UGT代谢都呈底物抑制模式,并且表观亲和常数(Km)在3.75~4.50μmol/L。阿卡宁和已知UGT1A9探针底物异丙酚在12例个体人肝中的UGT代谢具有很好的相关性,R2为0.88。化学抑制实验显示在HLM中,厚朴酚和尼氟灭酸对阿卡宁的UGT代谢具有明显的抑制作用;睾酮、雷公藤红素和尼罗替尼对阿卡宁的UGT代谢均无明显抑制作用。结论 UGT代谢是阿卡宁(紫草素)在人体的重要代谢途径之一,阿卡宁是人类UGT1A9的一个高选择性探针底物。
OBJECTIVE To study and characterize the oxygen-glucose exchange pathway of acanituron, a stereoisomeric monomer of shikonin. Methods Aqenin and its glucuronidation metabolites were detected by liquid chromatography-mass spectrometry (LC-MS / MS). The effects of acylamine on human liver microsomes (HLM), human renal microsomes (HKM), and recombinant human glucuronosyltransferase (UGT). The metabolic profile was observed, and the enzyme involved in the catalytic recombination was screened for enzyme kinetics. The correlation between UGT and Akt was analyzed by correlation analysis and chemical inhibition experiments. Results Akanine could detect 1 UGT metabolite in HLM incubation with uridine 5’-diphosphate glucuronic acid (UDPGA). UGT single enzyme screening found that UGT1A9 highly selective acylamine. Enzyme kinetic studies showed that UGT metabolism of acinon was substrate-inhibited in HLM, HKM and UGT1A9, and the apparent affinity constant (Km) ranged from 3.75 to 4.50 μmol / L. There was a good correlation between the presence of acinon and the UGT metabolism of UGT1A9 probe substrate in 12 individual human liver samples with a R2 of 0.88. Chemosuppression experiments showed that honokiol and niflumic acid had a significant inhibitory effect on Akan’s UGT metabolism in HLM; testosterone, tripterine and nilotinib had no significant effect on Akan’s UGT metabolism Inhibition. Conclusion UGT metabolism is one of the important metabolic pathways of acinon (shikonin) in the human body, and acinon is a highly selective probe substrate for human UGT1A9.