Urinary metabolite profiling reveals CYP1A2-mediated metabolism of NSC686288 (aminoflavone)
Urinary metabolite profiling reveals CYP1A2-mediated metabolism of NSC686288 (aminoflavone)
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DOI：
10.1124/jpet.106.105213
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发表时间：
2006-09-01
影响因子：
3.5
通讯作者：
Gonzalez, Frank J.
中科院分区：
文献类型：
--
作者：
Chen, Chi;Meng, Linghua;Gonzalez, Frank J.
NSC686288 [氨基黄酮 (AF)] 是一种候选化疗药物，具有独特的抗肿瘤细胞增殖特性。在一些基于细胞培养的研究中，药物代谢酶（尤其是 CYP1A 单加氧酶）对 AF 的代谢生物激活被认为是其选择性细胞毒性的潜在机制。然而，AF 的体内代谢尚未得到详细研究。在本研究中，通过精确质量测量和液相色谱-串联质谱裂解模式确定了小鼠尿液或微粒体孵育中的 13 种 AF 代谢物（其中 12 种是新的）的结构特性，包括三种单羟基-AF、两种二羟基-AF 及其硫酸盐和葡萄糖醛酸苷缀合物，以及一种 N-葡萄糖醛酸苷，并构建了 AF 代谢途径的综合图谱。野生型和 Cyp1a2 缺失小鼠在 AF 尿液代谢物的相对组成方面存在显着差异，表明 CYP1A2 介导的区域选择性氧化是 AF 代谢的主要贡献者。野生型和 CYP1A2 人源化小鼠之间的比较进一步揭示了 CYP1A2 介导的催化活性的种间差异。 AF 与来自所有三个小鼠品系的肝微粒体以及合并的人肝微粒体的孵育证实了尿代谢物分析的观察结果。酶动力学分析结果进一步表明，除CYP1A P450s外，CYP2C P450s也可能在AF的代谢中发挥一定作用。
NSC686288 [aminoflavone (AF)], a candidate chemotherapeutic agent, possesses a unique antiproliferative profile against tumor cells. Metabolic bioactivation of AF by drug-metabolizing enzymes, especially CYP1A monooxygenases, has been implicated as an underlying mechanism for its selective cytotoxicity in several cell culture-based studies. However, in vivo metabolism of AF has not been investigated in detail. In this study, the structural identities of 13 AF metabolites ( 12 of which are novel) in mouse urine or from microsomal incubations, including three monohydroxy-AFs, two dihydroxy-AFs and their sulfate and glucuronide conjugates, as well as one N-glucuronide, were determined by accurate mass measurements and liquid chromatography-tandem mass spectrometry fragmentation patterns, and a comprehensive map of the AF metabolic pathways was constructed. Significant differences between wild-type and Cyp1a2-null mice, within the relative composition of urinary metabolites of AF, demonstrated that CYP1A2-mediated regioselective oxidation was a major contributor to the metabolism of AF. Comparisons between wild-type and CYP1A2-humanized mice further revealed interspecies differences in CYP1A2-mediated catalytic activity. Incubation of AF with liver microsomes from all three mouse lines and with pooled human liver microsomes confirmed the observations from urinary metabolite profiling. Results from enzyme kinetic analysis further indicated that in addition to CYP1A P450s, CYP2C P450s may also play some role in the metabolism of AF.