Effects of long-term tea polyphenols consumption on hepatic microsomal drug-metabolizing enzymes and liver function in Wistar rats.
OBJECTIVE
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-transferase (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(-1)min(-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.


CONCLUSIONS
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.
Liu
Tao-Tao
TT
Department of Pharmacy, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, China.
Liang
Ning-Sheng
NS
Li
Yan
Y
Yang
Fan
F
Lu
Yi
Y
Meng
Zi-Qing
ZQ
Zhang
Li-Sheng
LS
D000633:Aminopyrine N-Demethylase / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000187:drug effects / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology*; D005982:Glutathione Transferase / Q000187:drug effects / Q000378:metabolism; D008111:Liver Function Tests; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000201:enzymology*; D010636:Phenols / Q000494:pharmacology*; D059808:Polyphenols; D051381:Rats; D017208:Rats, Wistar; D013662:Tea
D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D013662:Tea; D003577:Cytochrome P-450 Enzyme System; D000633:Aminopyrine N-Demethylase; D005982:Glutathione Transferase