Assessment of DNA strand breaks and total antioxidant status in patients with type 2 diabetes with and without complications: A case–control study

Abstract

Objective: To evaluate the total antioxidant status (TAS) and the extent of DNA strand breaks (damage) as a measure of oxidative stress biomarkers in patients with Type 2 diabetes (with and without complications) and controls. Methods: Blood samples were collected from 200 patients with Type 2 diabetes mellitus (n=100, with complications and n=100, without complications) and 100 healthy individuals. Oxidative DNA damage was evaluated using alkaline single cell gel electrophoresis (comet assay). TAS was assessed by ferric reducing ability of plasma assay. Results: TAS was found to be significantly lower in patients with Type 2 diabetes (with and without complications) compared to controls (p<0.001). Similarly, patients with complications of Type 2 diabetes mellitus had significantly lower TAS when compared to patients with diabetes (p=0.007). DNA damage analysis showed that the extent of damage was high in patients with diabetes mellitus (with and without complications) compared to controls (p<0.001). Fasting glucose and glycosylated hemoglobin level (HbA1C) were found to be significantly higher in patients with diabetes than controls (p<0.05). Correlation analysis showed that there is no association between age, duration, sugar level, HbA1C, TAS, and DNA damage in patients with Type 2 diabetes mellitus. Conclusion: Alterations in TAS and the extent of DNA damage were observed in patients with complications of diabetes mellitus indicate that oxidative stress is more in patients with complications when compared to patients without complications and healthy individuals. Therefore, further DNA damage and onset of complications in Type 2 diabetes mellitus could be prevented by counteracting the oxidative stress by therapeutic interventions using appropriate antioxidants.