评价HPPH对细胞色素P450酶体外代谢活性的影响

目的:评价HPPH在体外对大鼠及人肝微粒CYP450酶的6种亚型酶活性的影响,预测使用HPPH可能出现的药物相互作用。方法:将注射用HPPH与CYP450酶的6种亚型的特异性探针底物非那西汀(CYP1A2)、甲苯磺丁脲(CYP2C9)、S-美芬妥因(CYP2C19)、右美沙芬(CYP2D6)、氯唑沙宗(CYP2E1)、咪达唑仑(CYP3A4)和睾酮(CYP3A4)与大鼠及人肝微粒进行孵育反应,采用HPLC-MS/MS法测定对应的7种代谢产物(对乙酰氨基酚、羟基甲苯磺丁脲、4-羟基美芬妥因、O-去甲基右美沙芬、6-羟基氯唑沙宗、1′-羟基咪达唑仑、6β-羟基睾酮)的浓度。结果:在本实验条件下,HPPH浓度为1.00~50.00μmol·L-1时,未发现其对大鼠的CYP1A2、CYP2C9、CYP2D6、CYP2E1、CYP3A4产生抑制作用。在本实验条件下,HPPH浓度为0.50~10.00μmol·L-1时,未发现其对人CYP1A2产生抑制作用;但对人CYP2C9、CYP2C19、CYP2D6、CYP2E1均存在抑制作用;对人CYP3A4,对底物咪达唑仑存在抑制作用,对底物睾酮未发现抑制作用。结论:HPPH对CYP450酶的抑制作用存在种属差异,在人体内HPPH与CYP450酶作用有待体内实验进一步证明。

Assess the Effect of HPPH on Cytochrome P450

Objective： To evaluate the effects of HPPH on the selective CYP450 enzymes in rat andhuman liver microsomes, and to predict drug-drug interactions by using HPPH. Methods： Seven specificprobe drugs were utilized in present study, including phenacetin （CYP1A2）, tolbutamide （CYP2C9）, （S）-mephenytion （CYP2C19）, dextromethorphan （CYP2D6）, chlorzoxazone （CYP2E1）, midazolam （CYP3A4） andtestosterone （CYP3A4）. The concentrations of seven metabolites （paracetamol, hydroxy tolbumide, dextror-phan, 6-hydroxy chlorzoxazone, 1-hydroxy midazolam, 4-hydroxyl mephenytoin and 6茁-hydroxy testoster-tone） were determined by HPLC-MS/MS. Results： In tested experimental conditions, HPPH did not showany inhibitory effect on CYP1A2, CYP2C9, CYP2D6, CYP2E1 or CYP3A4 in rat when its concentrationranged from 1.00 to 50.00 μmol.L-1. In tested experimental conditions, HPPH, within the concentrationrange of 0.50 to 10.00 μmol.L-1, showed no inhibitory effect on human CYP1A2 but weak inhibitory effectson human CYP2C9, CYP2C19, CYP2D6 and CYP2E1. For CYP3A4, HPPH had weak inhibitory effect onprobe drug midazolam, but did not show any inhibitory effect on testosterone. Conclusion： The inhibitoryeffect of HPPH on CYP450 enzymes has species differences. The in vivo inhibitory effect of HPPH on hu-man CYP450 enzymes needs to be further investigated.