Efficacy of Alpha-Lipoic Acid against Diabetes-Induced Deterioration of Blood Antioxidants and Diabetic Retinopathy in Experimental Animals

The present study aimed to investigate the effect of alpha-lipoic acid (ALA) administration on diabetes-induced alterations of blood antioxidants and retinal histopathological changes. Forty albino Wistar rats of both sexes were used and divided into four groups; two groups (I and II) served as controls. In group III, diabetes was induced by a single intraperitoneal injection of alloxan 100 mg/kg. In group IV, diabetes was induced and rats received a daily oral dose of ALA 60 mg/kg/day for four months. Serum glucose, serum vitamin C and erythrocyte reduced glutathione levels were measured after 2 and 4 months. Then, animals were sacrificed and subjected to light microscopic examination of the retina. Untreated diabetic animals exhibited significant deterioration of the measured biochemical parameters in addition to marked histopathological retinal changes. Treatment with ALA improved significantly the diabetes-induced deterioration of vitamin C and glutathione in blood. In addition, the retina of these animals appeared normal with no significant deviation from the control retina suggesting its protective role against diabetic retinopathy