人类细胞染色体P4502C8将repaglinide代谢成4'-hydroxyrepaglinide,而不是3'-hydroxyrepaglinide
Raman Sharma1, Amanda Balesano1, Angela C Doran1
1Pfizer Inc., Groton, Connecticut.
Drug metabolism and disposition: the biological fate of chemicals
|October 30, 2025
概括
之前的研究错误地确定了repaglinide的主要代谢物. 这项研究纠正了结构,显示基化发生在4位,而不是3位,影响了CYP2C8活性研究.
科学领域:
- 药物代谢和药理动力学
- 酶动力学 酶动力学
- 有机化学 有机化学
背景情况:
- 细胞染色体P450 2C8 (CYP2C8) 对于像repaglinide这样的药物代谢至关重要.
- 雷帕格林的3'-氧化已被用作CYP2C8活性的生物标志物.
- 之前的报道错误地识别了雷帕格林化的氧化位点.
研究的目的:
- 为了明确确定由CYP2C8.8催化的雷帕格林化的正确位点.
- 为了纠正主要的氧化帕格林化物代谢物的结构赋值.
- 确保在药物代谢研究中准确解释CYP2C8活性.
主要方法:
- 使用复合CYP2C8.8.的repaglinide代谢物的生物合成.
- 使用高分辨率质谱学和1D/2DNMR光谱学进行隔离和结构阐明.
- 与合成标准和低温2DNMR进行比较分析,以确定结构赋值.
主要成果:
- 证明CYP2C8氧化物在4位,而不是3位的Repaglinide.
- 在人类肝脏显微体 (10.2μM) 和复合性CYP2C8 (5.4μM) 中确定4'-氧化的迈克利斯常数.
- 通过先进的光谱技术证实了4'-氧代谢物的结构.
结论:
- 由CYP2C8产生的repaglinide的主要氧代谢物是4'-hydroxymetabolite,而不是3'-hydroxyrepaglinide.
- 准确识别这种代谢物对于可靠评估CYP2C8活性至关重要.
- 这一发现需要重新评估以往依靠这种代谢标记物的体外和体内研究.
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