Role of Antioxidants in Protection Against Potassium Bromate Induced Lipid Peroxidation in the Rat

ABSTRACT Potassium bromate (KBrO3) has been classified as possible human carcinogen. Oxidative stress plays a major role in the carcinogenic action of KBrO3. So, the aim was to prove the prooxidative effect of KBrO3 and to evaluate and compare the possible protective effect of melatonin and ascorbic acid against lipid peroxidation in the thy-roids. Study was done on six groups of rats: (control group) treated with 0.9 % NaCl: ethanol (v/v 10:1), or KBrO3 in group II, or melatonin in group III, or ascorbic acid in group IV. Rats in groups V and VI were received either melatonin, or ascorbic acid combined with KBrO3. The results prove lipid peroxidation in the rat thyroid, followed KBrO3 injection. Treatment with melatonin or ascorbic acid did not affect the basal lipid peroxidation. However, the pre-treatments with either antioxidant ameliorate the lipoperoxidative changes and increase the expression of antioxidant enzymes in rat thyroid. In Conclusion, it is possible that these antioxidants may be of great value as protective agents against KBrO3-induced tumor induction in the thyroid. Melatonin is more powerful antioxidant than ascorbic acid. Potassium bromate (KBrO3) was used as a food additive in flour and barley processing and as a component in cold-wave hair lotions (8). Bromate is frequently detected in tap and bottled water, since it is an inorganic oxyhalide by-product