Free radicals in diabetic retinopathy

Serum enzymic antioxidants were estimated spectrophotometrically in 25 norm al cases, 25 diabetic cases without retinopathy, and 25 diabetic cases with retinopathy. Superoxide dismutase levels were significantly augmented in b oth groups of diabetic patients as compared with the control group. By cont rast, the catalase activity was significantly attenuated in diabetic patien ts, hut was more pronounced in diabetics without retinopathy. Similarly, th ere was a significant decrease in glutathione peroxidase in both diabetic g roups and was more pronounced in diabetics with retinopathy.