Study for sex differences of CYP3A enzymes using trans-chromosomic mice containing a human CYP3A gene cluster

本研究利用含有人细胞色素P3A基因簇的跨染色体小鼠进行的研究结果表明，肝脏中细胞色素P3A4的表达存在性别差异，并受雌二醇的正向调节。然而，雌激素不太可能通过雌激素受体α直接调节细胞色素P3A4的表达。此外，在诱导肝脏细胞色素P3A4表达方面也存在性别差异。有趣的是，CYP3A4在肠道中的表达和诱导没有性别差异。这些发现表明，尽管很难分析人类的性别差异，但在含有人的CYP3A基因簇的跨染色体小鼠中，肝脏中CYP3A4的表达存在性别差异。

Results of this study using trans-chromosomic mice containing a human CYP3A gene cluster suggested that expression of CYP3A4 in liver shows sex differences and is positively regulated by estradiol. However, it is unlikely that estradiol directly regulates the CYP3A4 expression via estrogen receptor alpha. In addition, it was suggested that there are sex differences in induction of CYP3A4 expression in liver. Interestingly, no sex difference was observed in the intestinal expression and induction of CYP3A4. These findings demonstrated that sex differences in the hepatic expression of CYP3A4 are observed in trans-chromosomic mice containing a human CYP3A gene cluster, although it is hard to analyze the sex differences in human.