Urea and Oxidative Stress in Type 2 Diabetes

Abstract

Introduction : Studies have shown altered protein metabolism in the presence of excess carbohydrate such as type 2 diabetes (T2DM). Protein metabolism is impaired in T2DM as a result of oxidative stress and insulin resistance. Here we aimed to study the correlation of serum urea as an indicator of protein metabolism with malondialdehyde (MDA) and superoxide dismutase (SOD), as indicators of oxidative stress in T2DM patients. Methods : We performed a cross sectional study on 151 patients with T2DM and 45 healthy controls. We quantified fasting blood sugar (FBS), HbA1C, lipid profile, urea, MDA and SOD in the studied groups. Results : Patients had a higher serum urea, FBS, HbA1C, triglyceride, cholesterol, LDL, MDA and SOD than controls. GFR and serum HDL levels were lower in patients. Diabetic men had a lower HDL and a higher albuminuria compared to diabetic women. There were no difference in any of the studied variables between men and women in control group. Serum urea levels were negatively correlated with MDA (r= -0.70, p<0.01) and SOD (r= -0.60, p<0.01) in men with type 2 diabetes. This was significant after multiple adjustments for HbA1C, GFR, albuminuria and duration of diabetes. Discussion : We showed the negative correlation of serum urea levels with the markers of oxidative stress in T2DM men. It could be concluded that protein metabolism and urea formation is more severely influenced in diabetic men. This explains the negative correlation of urea with MDA and SOD, only in men with T2DM.