Roles of CYP3A4 and CYP2C19 in methyl hydroxylated and N-oxidized metabolite formation from voriconazole, a new anti-fungal agent, in human liver microsomes
Roles of CYP3A4 and CYP2C19 in methyl hydroxylated and N-oxidized metabolite formation from voriconazole, a new anti-fungal agent, in human liver microsomes
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DOI：
10.1016/j.bcp.2007.03.012
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发表时间：
2007-06-15
影响因子：
5.8
通讯作者：
Yamazaki, Hiroshi
中科院分区：
文献类型：
--
作者：
Murayama, Norie;Imai, Naoko;Yamazaki, Hiroshi
细胞色素P450（P450或P450）2C 19，2C 9和3A 4参与伏立康唑，一种新的三唑类抗真菌剂，N-氧化，已被证明使用人肝微粒体。为了证实P450亚型在个体伏立康唑清除中的确切作用，我们研究了重组P450催化的伏立康唑氧化代谢以及CYP 2C 19基因分型的人肝微粒体。在使用大肠杆菌表达系统的重组P450亚型中，CYP 2C 19和CYP 3A 4具有伏立康唑N-氧化活性，但CYP 2C 9没有。CYP 2C 19和CYP 3A 4对伏立康唑N-氧化的表观Km和Vx值分别为14 +/- 6 μ M和0.22 +/- 0.02 nmol/min/nmol CYP 2C 19和16 +/- 10 μ M和0.05 +/- 0.01 nmol/min/nmol CYP 3A 4（平均值+/- S.E.）。CYP 3A 4从伏立康唑产生一种新的甲基羟基化代谢产物，通过LC/UV和LC/MS/MS检测，并通过H-1和C-13 NMR分析确认，Km和V-max值为11 +/- 3 μ M和0.10 +/- 0.01 nmol/min/nmol CYP 3A 4。基于报告的临床血浆水平，底物浓度为25 μ M时，野生型CYP 2C 19 *1/*1个体肝微粒体中伏立康唑4-羟基化与N-氧化代谢比（0.07）低于其他基因型（0.20-0.27）。这些结果表明，CYP 2C 19基因型，而不是CYP 2C 9基因型，将被评估为伏立康唑的药代动力学的一个关键因素，4-羟基伏立康唑的形成可能成为一个重要的途径，伏立康唑代谢的个体与CYP 2C 19催化功能差。(c)2007年爱思唯尔公司All rights reserved.
Involvement of cytochrome P450 (P450 or CYP) 2C19, 2C9, and 3A4 in N-oxidation of voriconazole, a new triazole antifungal agent, has been demonstrated using human liver microsomes. To confirm the precise roles of P450 isoforms in voriconazole clearance in individuals, we investigated the oxidative metabolism of voriconazole catalyzed by recombinant P450s as well as human liver microsomes genotyped for the CYP2C19 gene. Among recombinant P450 isoforms using Escherichia coli expression systems, CYP2C19 and CYP3A4 had voriconazole N-oxidation activities, but not CYP2C9. Apparent Km and V x values of CYP2C19 and CYP3A4 for voriconazole N-oxidation were 14 +/- 6 mu M and 0.22 +/- 0.02 nmol/min/nmol CYP2C19 and 16 +/- 10 mu M and 0.05 +/- 0.01 nmol/min/nmol CYP3A4, respectively (mean +/- S.E.). CYP3A4 produced a new methyl hydroxylated metabolite from voriconazole, detected by LC/UV and LC/MS/MS and confirmed by H-1 and C-13 NMR analyses, with Km and V-max values of 11 +/- 3 mu M and 0.10 +/- 0.01 nmol/min/nmol CYP3A4. The voriconazole 4-hydroxylation to N-oxidation metabolic ratios in liver microsomes from the wild-type CYP2C19*1/*1 individuals (0.07) were lower than those observed in other genotypes (0.20-0.27) at a substrate concentration of 25 mu M based on the reported clinical plasma level. These results suggest that the CYP2C19 genotype, but not CYP2C9 genotype, would be evaluated as a key factor in the pharmacokinetics of voriconazole and that 4-hydroxyvoriconazole formation may become an important pathway for voriconazole metabolism in individuals with poor CYP2C19 catalytic function. (c) 2007 Elsevier Inc. All rights reserved.