Abstract
INTRODUCTION: Herein the neuroprotective properties of melatonin, a highly effective antioxidant, administered in a single dose 50 mg/kg intraperitoneally, were investigated in the brain tissue of Wistar rats acutely exposed to the toxin carbon-tetrachloride (1 mL/kg, intraperitoneally). METHODS: To assess the degree of whole encephalic mass damage, biochemical parameters related to lipid and protein oxidation, antioxidant enzymes (catalase and superoxide dismutase), glutathione and inducible nitric oxide/arginase pathways were determined. RESULTS: The results showed that carbon-tetrachloride impaired the function of antioxidant enzymes (reduced catalase and superoxide dismutase activities) and reduced glutathione-metabolizing enzymes (reduced glutathione, glutathione S-transferase and peroxidase activity). Furthermore, carbon-tetrachloride increased lipid peroxidation and protein oxidative damage in the brain tissue, as well as myeloperoxidase and inducible nitric oxide synthase content/activities. CONCLUSIONS: The application of a single dose of melatonin post intoxication has been able to reverse the disturbance in the function of antioxidant enzymes and alleviate the tissue damage caused by oxidative stress, indicating that melatonin could be a potential therapeutic agent in oxidative-damage related neurodegenerative disorders.