咖啡因在大鼠及小鼠肝微粒体中体外代谢种属差异研究

咖啡因及其代谢产物在临床应用中具有重要作用,该文拟采用高分辨质谱系统对咖啡因经大鼠及小鼠肝微粒体代谢进行系统研究,以全面评价咖啡因体外代谢产物以及体外代谢的种属间差异。采用基于MMDF的UPLC-Q-TOF-MS/MS高分辨质谱系统,借助metabolitepolite软件,分析咖啡因经大鼠及小鼠肝微粒体代谢的产物及种属差异。研究发现咖啡因经大鼠及小鼠肝微粒体后产生除以往分析中的去甲基、氧化等产物之外,还存在甲基化、双氧化、脱水以及脱羰基新的代谢产物,并发现大鼠及小鼠体外代谢的明显差异。在小鼠体外代谢物中发现的去甲基代谢物M2(C₇H₈N₄O₂)和脱羰基代谢物M6(C₇H₁₀N₄)在大鼠体外代谢物中并为发现,但是在大鼠体外代谢中发现的M7(C₈H₁₂N₄O₅),在小鼠中并未发现。咖啡因药物在大鼠及小鼠的体外代谢存在明显种属差异,将对咖啡因进一步代谢研究及安全性评价提供重要参考价值。

Species differences in caffeine metabolism in liver microsomes of rats and mice

Caffeine and its metabolic products play an important role in clinical applications. An ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF MS/MS) method was applied to systemically study the caffeine metabolism in liver microsomes of rats and mice, and comprehensively evaluate caffeine metabolites in vitro and metabolism differences between species. The caffeine metabolites and metabolism differences between species in liver microsomes of rats and mice were analyzed by UPLC-Q-TOF-MS/MS high resolution mass spectrometry system and metabolitepolite software. The results showed that in addition to the demethylated and oxidized products in previous analysis, methylated, double oxidized, dehydrated and decarbonylated metabolites were also found in caffeine metabolism in liver microsomes of rats and mice, with significant difference in metabolism in vitro between rats and mice. The demethylated metabolite M2(C₇H₈N₄O₂) and decarbonylated metabolite M6(C₇H₁₀N₄) in metabolism in vitro of mice were not found in rats, and the in vitro metabolite M7(C₈H₁₂N₄O₅) in rats were not found in mice. There was significant species difference in caffeine metabolism in vitro between rats and mice, providing important reference value for the further metabolism study and safety evaluation of caffeine.