Effects of long-term tea polyphenols consumption on hepatic microsomal drug-metabolizing enzymes and liver function in Wistar rats

摘要

AIM: To investigate the effects of long-term tea polyphenols (TPs) consumption on hepatic microsomal drug-metabolizing enzymes and liver function in rats.METHODS: TPs were administered intragastrically to rats at the doses of 833 mg·kg^-1·d^–1 (n = 20) and 83.3 mg·kg^-1·d^-1 (n = 20) respectively for six months. Controlled group (n = 20) was given same volume of saline solution. Then the contents of cytochrome P450, b5, enzyme activities of aminopyrine N-demethylase (ADM), glutathione S-trasferase (GST) and the biochemical liver function of serum were determined.RESULTS: The contents of cytochrome P450 and b5 in the livers of male rats in high dose groups (respectively 2.66 ± 0.55, 10.43 ± 2.78 nmol·mg MS pro^-1) were significantly increased compared with the control group (1.08 ± 1.04, 5.51 ± 2.98 nmol·mg MS pro^{- 1}; P < 0.01, respectively). The enzymatic activities of ADM in the livers of female rats in high dose groups (0.91 ± 0.08 mmol·mg MS pro^-1min^-1) were increased compared with the control group (0.82 ± 0.08 mmol·mg MS pro^-1·min^-1; P < 0.05). The GST activity was unchanged in all treated groups, and the function of liver was not obviously changed.CONCLUSION: The antidotal capability of rats’ livers can be significantly improved after long-term consumption of TPs. There are differences in changes of drug-metabolizing enzymes between the sexes induced by TPs and normal condition.