Alternations in free radical erythrozyte-defense mechanisms in streptozotocin induced diabetic rats - effect of antioxidant treatment

The activities of superoxide dismutase, glutathione peroxidase and the cont ents of glutathione, malondialdehyde were examined in erythrocytes of strep tozotocin induced diabetic rats. The above mentioned antioxidant systems of erythrocyte were determined after treatment of diabetic rats with superoxi de dismutase, trolox, catalase and allopurinol. In erythrocytes of streptoz otocin induced diabetic rats the activities of superoxide dismutase, glutat hione peroxidase as well as the levels of reduced glutathione were lower wh ereas the contents of oxidized glutathione and malondialdehyde were higher than in controls. Superoxide dismutase and trolox treatment of diabetic rat s resulted in an increase of erythrocyte glutathione peroxidase activities and in reduced glutathione levels. However the levels of oxidized glutathio ne decreased after treatment of diabetic rats with superoxide dismutase and trolox. Catalase and allopurinol administration did not have any influence on the activities of the investigated enzymes nor on the levels of glutath ione in diabetic rats. The antioxidants under study did not cause any chang es in the increased level of malondialdehyde in erythrocytes.