Correlation of Uric Acid with Oxidative Stress and Endothelial Dysfunction in Type 2 Diabetes Mellitus

Abstract

Objective: To evaluate the correlation of uric acid with oxidative stress and endothelial dysfunction in type 2 diabetic subjects. Material and Methods: The study included 120 subjects, among them 60 were type 2 diabetes subjects and the remaining 60 were age and gender matched healthy controls. The biochemical parameters, blood glucose, lipid profile, uric acid and homocysteine, were measured by standard kits in an autoanalyzer. Oxidative stress was evaluated by measuring malondialdehyde (MDA) and total antioxidant power by manual methods such as thio-barbituric acid reactive substances and ferric reducing ability of plasma (FRAP). Endothelial dysfunction was assessed by measuring nitric oxide (NO) by the kinetic cadmium method. Results: A significant elevation of triglycerides, low density lipoprotein (LDL), and MDA were observed in the type 2 diabetes mellitus patients while FRAP and NO were significantly reduced compared to the healthy controls. In addition, the uric acid levels had a highly significant correlation with FRAP (r=0.212, p-value=0.020), and moderately significant correlation with triglycerides (r=0.173, p-value=0.057) and homocysteine (r=0.178, p-value=0.051). Uric acid was negatively correlated with MDA and positively correlated with NO, but not statistically significant. Conclusion: Our findings suggest that uric acid may have antioxidant properties since it had a significant positive correlation with FRAP.