Urinary markers of oxidative DNA damage in type 1 diabetic children: Relation to microvascular complications

Abstract

Objective: Type 1 diabetes mellitus (T1DM) is a widespread metabolic disease, which frequently carries with it a significant impact on human health. Oxidative damage and tissue inflammation have been claimed to be a typical pathogenic component for the progression of diabetic complications. We aim in this study to explore the relation of urinary 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) (as a marker of nucleic acid oxidation) to microvascular complications in T1DM. Methods: A case–control study, enrolling 45 T1DM children and an equivalent number of healthy subjects, was performed. Full clinical examination and anthropometric measurement were performed to all subjects. Urinary assessment for 8-oxodG and albumin was done in addition to blood sampling for lipid profile and glycated Hb (HbA1c) assay. Complete ocular examination for assessment of diabetic retinopathy (DR) was also done. Results: Levels of urinary 8-oxodG, serum cholesterol, triglycerides, and low-density lipoprotein in cases were significantly higher than non-diabetics; these levels were likewise higher in uncontrolled T1DM patients in comparison with well-controlled T1DM subjects. Urinary 8-oxodG and HbA1c were significantly higher in diabetic patients with albuminuria and DR compared to patients without complications. Significant positive correlation was found between 8-oxodG with HbA1c (r=0.8, p<0.01), diastolic blood pressure (DBP) (r=0.4, p=0.02), and cholesterol (r=0.4, p=0.05). Conclusion: Urinary 8-oxodG was found to be a reliable marker for assessing oxidative DNA damage in T1DM and can be used in the determination of microvascular complications related to diabetes.