大黄5种蒽醌类成分在大鼠肝微粒体中的代谢及酶促反应动力学  

Metabolism and enzyme kinetics of five anthraquinones in rhubarb in rat liver microsomes

作　　者：冯素香[1,2] 王蒙蒙[1] 吴兆宇[1] 李先[1] 郝蕊[1] 徐艳华[1] 

机构地区：[1]河南中医学院,河南郑州450046 [2]呼吸疾病诊疗与新药研发河南省协同创新中心,河南郑州450046

出　　处：《暨南大学学报（自然科学与医学版）》2015年第5期383-391,共9页Journal of Jinan University(Natural Science & Medicine Edition)

基　　金：国家自然科学基金资助项目(81274179)

摘　　要：研究大黄5种蒽醌类成分在大鼠肝微粒体中的代谢特征和参与代谢的细胞色素P450亚型.超速离心法制备大鼠肝微粒体,采用反相高效液相色谱(RP-HPLC)测定孵育液中大黄5种蒽醌类成分的质量浓度,研究大黄蒽醌类成分的酶促动力学,推导药物米氏常数(Km)和最大反应速度(Vmax),并计算体外酶对药物的清除率(Clint);用苯巴比妥钠(PB)、地塞米松(DEX)、β-奈黄酮(β-NF)诱导大鼠肝微粒体,观察大黄5种蒽醌类成分在各温孵体系中的代谢,同时观察不同质量浓度和不同种类的CYP酶特异性抑制剂对大黄蒽醌类成分代谢的影响.结果表明大黄芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚在肝微粒体中的Km、Vmax、Clint分别为(18.97±1.89)、(2.50±0.11)、(15.68±1.09)、(183.41±1.90)、(1.37±0.14)mg·L-1;(0.52±0.015)、(0.066±0.003)、(0.41±0.009)、(5.22±0.09)、(0.036±0.0034)mg·L-1·min-1;(2.69±0.12)、(2.56±0.16)、(2.61±0.20)、(2.81±0.10)、(2.63±0.18)min-1·10-2;经DEX、PB、β-NF诱导后,PB组、DEX组大黄蒽醌类成分代谢率高于CMC-Na组,具有显著性差异(P<0.05),β-NF组大黄蒽醌类成分代谢率低于CMC-Na组,无显著性差异(P>0.05);非那西汀、氟康唑、酮康唑的Dixon图均为一组相交于第二象限的直线.通过研究得知大黄5种蒽醌类成分在PB、DEX诱导的肝微粒体中代谢较快,CYP3A4、CYP2A6为介导大黄蒽醌类成分代谢的主要代谢酶;非那西汀、氟康唑、酮康唑均为为大黄蒽醌类成分的竞争性抑制剂.To study the metabolic kinetics of anthraquinones in rhubarb and participate in the metabo-lism of cytochrome P450 isoforms in rat liver microsomal enzyme.Rat liver microsomes were prepared by using ultra-centrifugation method.anthraquinones in rat concentration in the incubation pool was deter-mined by RP-HPLC method.The Michaelis-Menten parameters Km and Vmax in rat liver microsomes were initially estimated by analyzing Lineweave-Brurk plot.The clearance （Clint ）was calculated for in vitro enzyme to anthraquinones in rhubarb.Various selective CYP inhibitors were used to investigate their in-hibitory effects on the metabolism of anthraquinones in rhubarb and the principal CYP isoforms involved in anthraquinones in rhubarb metabolic ring.The Km,Vmax,and CLint of aloe emodin,rhein,emodin,＆nbsp;chrysophanol,and physcion were（18.97 ±1.89）,（2.50 ±0.11）,（15.68 ±1.09）,（183.41 ±1.90）, （1.37 ±0.14）mg·L -1;（0.52 ±0.015）,（0.066 ±0.003）,（0.41 ±0.009）,（5.22 ±0.09）,（0.036 ±0.0034）mg·L -1 ·min -1;（2.69 ±0.12）,（2.56 ±0.16）,（2.61 ±0.20）,（2.81 ±0.10）,（2.63 ±0.18）min -1 ·10 -2 .After the induction of DEX,PB,β-NF,the anthraquinones in rhubarb metabolic rate of PB group and DEX group were higher than that of CMC-Na group,with a significant difference （P 〈0.05）;the anthraquinones in rhubarb metabolic rate of β-NF group was lower than CMC-Na group （P 〉0.05）,both acetophenetidine,fonazole and ketoconazole＇s Dixon diagram were linears intersects the second quadrant.After induced by PB,DEX,the metabolism of anthraquinones in rhubarb were increase in rat liver microsomes.It was shown that CYP3A4 and CYP2A6 are involved in the metabolism of anthra-quinones in rhubarb,Both Acetophenetidine,Fluconazole and Ketoconazole were competitive inhibitors of anthraquinones in rhubarb.

关 键 词：大黄蒽醌类成分 大鼠肝微粒体 CYP450 酶促动力学 

分 类 号：R285.8[医药卫生—中药学]