Antioxidant Enzymes and Lipid Peroxidation in Alloxan-Induced Diabetic Rabbits

The study was carried out to evaluate the effect of alloxan–induced diabetes on some oxidative stress markers in rabbits. Ten rabbits weighing between 1.0-1.5kg were used and divided into two groups of five rabbits each. Diabetes was induced in one of the groups, by intraperitonial administration of alloxan at a dosage of 150mg/kg body weight and the control rabbits were administered normal saline (0.9% NaCl). The animals were monitored for 14days after confirmed diabetes in the test group. The fasting plasma glucose, plasma insulin, plasma lipids, the antioxidant enzymes: Superoxide dismutase (SOD), catalase, and lipid peroxidation were assayed for, in the plasma and the brain of the diabetic and non-diabetic rabbits. The results showed a significant decrease in mean body weight of the alloxan-induced diabetic and control rabbits pre and 14days post alloxan-induction. There was a significant (p < 0.01) increase in fasting plasma glucose, a significant (p < 0.01) decrease in the activity of SOD and a significant (p < 0.01) increase in the activity of catalase in the plasma and brain; there was also a significant (p < 0.01) increase in the level of lipid peroxidation, plasma cholesterol and triglycerides in the diabetic rabbits. Culminating a depletion of SOD activity, the altered activity of plasma (or brain) catalase and increased lipid peroxidation is due to the oxidative stress induced by the diabetic condition, hence the present study indicate that alloxan – induced diabetic potentiated oxidative stress in a short term duration. This shows the importance of antioxidant mimetics to be administered at early stage of diabetics in other to increase the antioxidant capacity thus preventing oxidative stress which may lead to complication in diabetes