Study of oxidative stress in type 2 diabetic patients and its relationship with glycated hemoglobin

ABSTRACT

To evaluate the activity of antioxidant enzymes in diabetic patients and also to determine the correlation between hyperglycemia and lipid peroxidation. Thirty patients with type 2 diabetes and 30 healthy individuals [control group] participated in this case-control study. The patients were referred to Sina Hospital, Hamadan, Iran from April to June 2006. Glycated hemoglobin [HbA1c] was measured as a marker of hyperglycemia using the chromatography method [Biosystem] and malondialdehyde [MDA] was determined using the colorimetric method. Glutathione peroxidase [GPx] and superoxide dismutase [SOD] activity were assessed using the UV-Vis spectrophotometric technique [Randox kit]. The mean of HbA1c was higher in diabetic patients compared to the healthy group, and the difference was statistically significant [p<0.001]. Serum MDA in diabetics was higher compared to those of healthy subjects [p<0.001]. There were significant differences in activities of SOD and GPx between the 2 studied groups indicating lower activity in diabetic patients [p<0.001]. There was a significant relationship between MDA and HbA1c in diabetic and healthy subjects. The data showed an increase in lipid peroxidation and oxidative stress in diabetes and also indicated a positive correlation between the degree of hyperglycemia and oxidative stress. Evaluation of oxidative status and choosing the appropriate treatment may help to support antioxidant defense in these patients