Protective effects of green tea on hepatotoxicity, oxidative DNA damage and cell proliferation in the rat liver, induced by repeated oral administration of 2-nitropropane

To evaluate the benefit of green tea in mitigating hazards caused by repeat ed exposure of 2-nitropropane (2NP), we examined the effects of the tea on toxic indices, oxidative DNA damage and cell proliferation in the liver of 2NP-treated rats. Male Fischer 344 rats were administered. by gastric intub ation, a total of six doses of 60 mg/kg 2NP(L), or alternatively two doses of 90 mg/kg and then four doses of 120 mg/kg 2NP(H) during 2 weeks. Green t ea infusion was given to the rats as drinking water I week before the 2NP t reatments and throughout the experiment. Significant elevation of hepatotox ic indices was evident in the 2NP(H)-treated group, such as an increase of serum plutamic-oxaloacetic transaminase (GOT) activity and of hepatic lipid peroxidation, together with a decrease in hepatic glycogen and serum trigl yceride, and degenerative changes in the hepatocytes. A dose-related increa se was observed in oxidative DNA damage and cell proliferation in the liver . Green tea effectively inhibited all of above changes induced by 2NP treat ment, suggesting that tea intake may be effective for preventing the hepati c injuries after chronic exposure to 2NP. (C) 1998 Elsevier Science Lid. Al l rights reserved.