Abstract
Background: Oxidative stress plays a pivotal role in the development of diabetic complications, both microvascular and cardiovascular. The metabolic abnormalities of diabetes cause several mechanisms that induce diabetic tissue damage. Important mechanism is the production of reactive oxygen species (ROS). Diabetic retinopathy is the leading cause of vision impairment and blinding among working adult. This study aimed to assess the level of Superoxide dismutase, glutathione peroxidase and vitamin E in patients with diabetic with and without retinopathy. Setting: Departments of Internal Medicine, Ophthalmology, Medical Biochemistry Faculty of Medicine, Zagazig University. Subjects and Methods: This study included 128 patients divided into 4 groups. 30 Diabetic patients without retinopathy, 34 diabetic patients with proliferative retinopathy -PDR-, 34 diabetic patients with non proliferative retinopathy-NPDR-, and 30 subjects as a healthy control group. All subjects were subjected to history taking, full clinical and funds examination. Laboratory investigations were done including Superoxide dismutase (SOD) Glutathione Peroxidase (GPx) and vitamin E levels were measured. Results: fasting blood glucose level, cholesterol, LDL and triglyceride were higher in diabetic patients and HDL lower in diabetic patients with and without retinopathy while Superoxide dismutase, Glutathione Peroxidase and vitamin E levels were decreased in diabetic patients compared to healthy control with more decrease in diabetic level with retinopathy than those without retinopathy. Correlation of Superoxide dismutase, Glutathione Peroxidase (GPx) with studied parameters in diabetic patients shows negative correlation with fasting blood glucose, LDL, triglyceride and creatinine and significant positive correlation with HDL. While correlation of vitamin E and the studied parameters it shows significant negative correlation with fasting blood glucose, LDL and triglyceride significant positive correlation with HDL and no correlation with creatinine and cholesterol. SOD, GPx and vitamin E are positively correlated with each other. Conclusion: Superoxide dismutase, Glutathione Peroxidase and vitamin E are important components in the cell defense against oxidative stress.