Antioxidant Enzymes and Lipid Peroxidation in Type 2 Diabetes Mellitus Patients with and without Nephropathy

BACKGROUND: Oxidative stress has been considered to be a pathogenic factor of diabetic complications including nephropathy. There are many controversies and limited studies regarding the antioxidant enzymes in diabetic nephropathy. AIM: This study was to evaluate the levels of antioxidant enzymes and lipid peroxidation in Type-2 Diabetes Mellitus (DM) patients with and without nephropathy. MATERIALS AND METHODS: The study included 90 age and sex matched subjects. Blood samples of all subjects were analyzed for all biochemical and oxidative stress parameters. RESULTS: The malondialdehyde (MDA) levels and catalase (CAT) activity were significantly increased and reduced glutathione (GSH) levels and activities of glutathione peroxidase (GPx) and glutathione reductase (GR) were significantly decreased in Type-2 DM with and without nephropathy as compared to controls and also in Type-2 DM with nephropathy as compared to Type-2 DM without nephropathy. There were an excellent positive correlation of glycohemoglobin (HbA1c) with MDA and a good negative correlation of GPx with GSH in controls. There were positive correlations of GR, CAT, and superoxide dismutase (SOD) with MDA in Type-2 diabetes patients with nephropathy. CONCLUSIONS: Intensity of oxidative stress in Type-2 diabetic patients with nephropathy is greater when compared with Type-2 diabetic patients without nephropathy as compared to the controls.