New biomarker evidence of oxidative DNA damage in patients with non-insulin-dependent diabetes mellitus

AbstractUrinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) has been reported to serve as a sensitive biomarker of oxidative DNA damage and also of oxidative stress. We have investigated oxidative DNA damage in patients with non-insulin-dependent diabetes mellitus (NIDDM) by urinary 8-OHdG assessments. We determined the total urinary excretion of 8-OHdG from 24 h urine samples of 81 NIDDM patients 9 years after the initial diagnosis and of 100 non-diabetic control subjects matched for age and gender. The total 24 h urinary excretion of 8-OHdG was markedly higher in NIDDM patients than in control subjects (68.2±39.4 μg vs. 49.6±37.7 μg, P=0.001). High glycosylated hemoglobin was associated with a high level of urinary 8-OHdG. The increased excretion of urinary 8-OHdG is seen as indicating an increased systemic level of oxidative DNA damage in NIDDM patients