Effects of green tea on ACE gene expression in rat liver in CCl4-induced cirrhosis

Aim: This study was designed to investigate the beneficial effects of green tea administration on angiotensin converting enzyme (ACE) gene expression in CCl4-induced liver cirrhosis in rats. Materials and methods: A total of 24 male Wistar rats were divided into 3 groups as: Group 1, normal untreated rats; Group 2, CCl4 induced cirrhotic rats; Group 3: CCl4-induced cirrhotic + green tea treated rats. The beneficial effects of green tea were measured by alanine aminotransferase (ALT), alkaline phosphatase (ALP), total and direct bilirubin level, tissue malondialdehyde (MDA), super oxide dismutase (SOD), and catalase (CAT). The genomic DNA was isolated from excised tissue to determine the ACE genotypes using specific primers. The ACE gene expression in liver tissue was assessed using the quantitative RT-PCR method. Results: Liver cirrhosis was indicated by high plasma ALT, direct bilirubin level, tissue MDA, and low SOD. The antioxidant enzymes SOD and CAT were low (P < 0.01) in cirrhotic and green tea-treated rats. High activity (P < 0.01) of ALT was observed in green tea-treated cirrhotic rats. The total and direct bilirubin levels were high (P < 0.01) in CCl4-treated cirrhotic rats while they were low (P < 0.05) in green tea-treated cirrhotic rats. The tissue MDA was high (P < 0.01) in CCl4- and green tea-treated cirrhotic rats. ACE gene expression after 8 weeks of CCl4 treatment in cirrhotic rats was significantly high (P < 0.05), and was reversed in green tea-treated cirrhotic rats in comparison to controls. Conclusion: The administration of green tea tries to correct the deteriorative biochemical and genetic changes during CCl4-induced liver cirrhosis in rats. The long-term consumption of green tea has beneficial effects on abnormally increased ACE gene activity during liver cirrhosis caused by CCl4 administration in rats.