title: Effects of long-term tea polyphenols consumption on hepatic microsomal drug-metabolizing enzymes and liver function in Wistar rats.
abstract: 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.
authors.affiliation: Department of Pharmacy, First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, China.
authors.forename: Tao-Tao
authors.initials: TT
authors.lastname: Liu
authors.forename: Ning-Sheng
authors.initials: NS
authors.lastname: Liang
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
authors.forename: Zi-Qing
authors.initials: ZQ
authors.lastname: Meng
authors.forename: Li-Sheng
authors.initials: LS
authors.lastname: Zhang
mesh_terms: 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
chemical_list: D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D013662:Tea; D003577:Cytochrome P-450 Enzyme System; D000633:Aminopyrine N-Demethylase; D005982:Glutathione Transferase