Chemopreventive efficacy of ginger (Zingiber officinale) in ethionine induced rat hepatocarcinogenesis
Ginger (Zingiber officinale Rosco) is widely used in foods as a spice all around the world. It has been reported to have antioxidant and anticarcinogenic properties. We investigated the effect of ginger in ethionine induced rat hepatocarcinogenesis. Male Wistar rats were divided into 5 groups: group 1 and 2 served as controls and they received normal rat chow and olive oil respectively. Group 3 was fed with ginger oleoresin dissolved in olive oil at 100 mg/kg body wt. Group 4 was fed with choline deficient diet and 0.1% ethionine in drinking water (CDE diet), and group 5 received ginger with CDE diet. Blood samples were taken from the orbital sinus at 0 and 8 weeks of experiment for the determination of antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase and lipid peroxidation end product, malondialdehyde (MDA). Rats were also killed at 8 weeks for the observation of liver tumor formation. CDE diet induced the formation of liver nodules in rats and increased SOD
activity. However, it had no effect on catalase, GPx and MDA levels when compared to both controls at 8 weeks of experiment. When CDE rats were treated with ginger, the formation of liver tumour, SOD activity and MDA level reduced, catalase activity was increased but no change was observed for GPx activity when compared to CDE group. In conclusion, ginger supplementation suppressed liver carcinogenesis by scavenging the free radical formation, and by reducing lipid peroxidation.
Keywords: Choline deficient diet, Ethionine, Liver cancer, Ginger, Antioxidants, Lipid peroxidation