马钱子碱和士的宁在人肝微粒体和UGT1A4重组酶中的体外酶动力学研究  

Metabolic kinetics of strychnine and brucine in human liver microsomes and UGT1A4 enzyme in vitro

作　　者：李阿荣 李丽明[2] 邓志军[2] 刘若轩[2] 郭洁文[2] 袁牧[3] 徐峰[4] LI Arong;LI Liming;DENG Zhijun;LIU Ruoxuan;GUO Jiewen;YUAN Mu;XU Feng(Guangzhou Hospital of TCM,Guangzhou University of Chinese Medicine,Guangzhou 510405,China;Guangzhou Hospital of Traditional Chinese Medicine,Guangzhou 510130,China;The Drug Research Center,Guangzhou Medical University,Guangzhou 510182,China;Fengxian Hospital of Southern Medical University,Shanghai 201400,China)

机构地区：[1]广州中医药大学附属广州中医院,广东广州510405 [2]广州市中医医院,广东广州510130 [3]广州医科大学药物研究中心,广东广州510182 [4]上海市奉贤区中心医院,上海201400

出　　处：《广东药科大学学报》2018年第5期541-546,共6页Journal of Guangdong Pharmaceutical University

基　　金：广州市中医药和中西医结合科研项目(20172A011009;20162A011011);广东省药学会研究基金项目(2018A11;2016A03)

摘　　要：目的考察士的宁和马钱子碱在体外人肝微粒体(HLMs)和UDP-葡萄糖醛酸转移酶(UGTs) 1A4中的代谢动力学,及UGT1A4抑制剂对士的宁和马钱子碱在HLMs中葡糖醛酸化反应的抑制作用。方法采用HPLC-MS/MS测定士的宁和马钱子碱在体外孵育体系中代谢产物含量,Graph Pad Prism软件计算酶促反应最大反应速率(Vmax)、米氏常数(Km)等酶动力学参数;通过抑制试验观察UGT1A4特异性抑制剂海柯皂苷元对士的宁和马钱子碱在HLMs中Ⅱ相代谢影响。结果在HLMs和UGT1A4孵育体系中,马钱子碱和士的宁均生成1个单葡萄糖醛酸代谢产物,二者在HLMs中的代谢产物酶促反应参数Km分别为(76.23±7.77)、(66.55±11.46)μmol/L,Vmax分别为(4.21±0.24)、(6.60±0.59) nmol/(min·mg);在人重组UGT1A4孵育体系中Km分别为(56.52±11.63)、(63.33±13.32)μmol/L,Vmax分别为(8.30±0.83)、(2.53±0.27) nmol/(min·mg)。HLMs孵育体系中加入UGT1A4特异性抑制剂海柯皂苷元后,马钱子碱和士的宁代谢产物含量均显著降低。结论 UGT1A4是马钱子碱和士的宁Ⅱ相代谢葡糖醛酸化主要亚酶,临床可能存在二者基于UGT1A4酶的药物相互作用。Objective To study the metabolic kinetics of strychnine and brucine in human liver microsomes （HLMs） and UGT1A4,and the effects of UDP-glucuronosyl transferases （UGTs） 1A4 inhibitors on the metabolism of strychnine and brucine in HLMs. Methods The glucuronide metabolites of strychnine and brucine were determined by HPLC-MS/MS. The Michaelis-Menten parameters K m and Vm were estimated by GraphPad Prism. Hecogenin （selective UGT1A4 inhibitor） was used to investigate inhibitory effects on the metabolism of strychnine and brucine in HLMs. Results Mono-glucuronidation of strychnine and brucine was found in HLMs and UGT1A4. The kinetic parameters for the glucuronidation of strychnine and brucine in HLMs were as follows： K m of （76.23±7.77） and （66.55±11.46） μmol/L respectively,and V max of （4.21±0.24） and （6.60±0.59） nmol/（min ·mg）,respectively. Meanwhile the kinetic parameters in UGT1A4 supersome were as follows： K m of （56.52±11.63） and （63.33±13.32） μmol/L respectively,and V max of （8.30±0.83） and （2.53±0.27） nmol/（min ·mg） repectively. Both strychnine and brucine glucurono-syltransferase activities in HLMs were inhibited by hecogenin. Conclusion UGT1A4 is a major subtype mediated strychnine and brucine glucuronidation,which indicates its potential drug interactions based on UGT1A4 enzyme.

关 键 词：士的宁 马钱子碱 人肝微粒体 UGT1A4 酶动力学 

分 类 号：R965[医药卫生—药理学]