Analysis of DNA damage, plasma lipid peroxidation, and antioxidant status in type 2 diabetes mellitus patients among a south Indian population

Oxidative stress is involved in the pathophysiology of diabetes mellitus, which in turn may also contribute to its complications. This case-control study was designed to find out the association between oxidative damage to lipids and DNA in type 2 diabetes mellitus. Sixty individuals with type 2 diabetes and age- and sex-matched 60 clinically healthy individuals without type 2 diabetes were included for the study. Oxidative stress was evaluated by malondialdehyde assay which is a marker of lipid peroxidation and plasma total antioxidant status was evaluated by the ferric reducing antioxidant power assay. Single-cell alkaline gel electrophoresis (comet assay) was employed to assess the level of DNA damage in peripheral lymphocytes. The extent of DNA damage was observed to be high in the diabetic patients when compared with the controls. The total antioxidant status was found to be significantly lower in the patients with diabetes mellitus when compared with the controls (p < 0.05). Lipid peroxidation status was significantly increased in diabetics (p < 0.05) when compared with the control group. The results of this study confirm that hyperglycemia contributes to increased generation of reactive oxygen species and decreased total antioxidant status which may be responsible for the oxidative DNA damage among south Indian population with diabetes mellitus.