[Effects of green tea extract on galactosamine-induced hepatic injury in rats]

The present study examined the preventive effects of green tea extract on D-galactosamine (GalN)-induced hepatic injury in rats, an animal model of viral hepatitis. A single i.p.-injection of GalN (700 mg/kg) to male Wistar rats caused fulminant hepatitis by 48 hr as assessed by marked increases in the serum aspartate aminotransferase (GOT), alanine aminotransferase (GPT) and alkaline phosphatase (ALP) activities; decreases in the serum protein and cholesterol levels and the amount of liver microsome P-450; and marked changes in organ weights. The lecithin: cholesterol acyltransferase (LCAT) activity markedly increased at 8 hr and markedly decreased at 24 hr after the GalN injection. In the experiment, animals were orally administered green tea extract at doses of 50, 100 or 200 mg/kg five times each before and after the GalN injection. Treatment with green tea extract significantly prevented the increases in the GOT, GPT and ALP activities in a dose-related manner. It also significantly prevented the decreases in serum albumin and total cholesterol, although not in a dose-related manner. A tendency to prevent the increase in LCAT activity and the decrease in liver microsome P-450 was also noted. Little effect was found on the other abnormal changes in the serum lipids and proteins and the organ weights. These results suggest that green tea may have an ameliorating effect on hepatic dysfunction.