The effects of aqueous extract of white tea on serum antioxidant enzymes in rats exposed to arsenic

Oxidative stress is a condition is which the biological system's ability to detoxify and eliminate harmful effects of free radicals is not sufficient and oxidative damages to cells or tissues  leads to the development of diseases such as cancer, arteriosclerosis and degenerative changes. Phenolic compounds due to their high antioxidant capacity, have an important role in health and increase the antioxidant defense against oxidative stress. The aim of this study was to evaluate the effect of aqueous extract of white tea on status of antioxidant enzymes (SOD, CAT and GPx), MDA (malondialdehyde) and TAC (total antioxidant capacity) in rats treated with sodium arsenite. In this study, 32 adult male rats weighing 200-250 g were used in four groups of eight. The first group included healthy normal rats (control group), the second group of rats were treated with sodium arsenite (100 ppm in drinking water) the third group of rats were treated with aqueous extract of white tea at a concentration of 1/5%, via gavage, the fourth group of rats were treated with aqueous extract of white tea (1/5%) via gavage with sodium arsenite (100 ppm in drinking water). The rats were killed at the end of the 28th day of treatment and blood samples were collected and the antioxidant enzymes of CAT (catalase), SOD (superoxide dismutase), GPx (glutathione peroxidase), and MDA and TAC were measured. The results indicate that the aqueous extract of white tea significantly increased the activities of SOD, GPx, CAT and TAC and decreased   MDA concentration (p<0.05). The results showed consummation of white tea decreased the oxidative stress of arsenic by increasing the activity of antioxidant enzymes and potentiation of antioxidant defense system.