Increased DNA dicarbonyl glycation and oxidation markers in patients with type 2 diabetes and link to diabetic nephropathy

Aim. the aim of this study was to assess the changes of markers of dna damage by glycation and oxidation in patients with type 2 diabetes and the association with diabetic nephropathy. methodology. dna oxidation and glycation adducts were analysed in plasma and urine by stable isotopic dilution analysis liquid chromatography-tandem mass spectrometry. dna markers analysed were as follows: the oxidation adduct 7,8-dihydro-8-oxo-2′-deoxyguanosine (8-oxodg) and glycation adducts of glyoxal and methylglyoxal-imidazopurinones gdg,mgdg,and n2-(1,r/s-carboxyethyl)deoxyguanosine (cedg). results. plasma 8-oxodg and gdg were increased 2-fold and 6-fold,respectively,in patients with type 2 diabetes,with respect to healthy volunteers. median urinary excretion rates of 8-oxodg,gdg,mgdg,and cedg were increased 28-fold,10-fold,2-fold,and 2-fold,respectively,in patients with type 2 diabetes with respect to healthy controls. in patients with type 2 diabetes,nephropathy was associated with increased plasma 8-oxodg and increased urinary gdg and cedg. in a multiple logistic regression model for diabetic nephropathy,diabetic nephropathy was linked to systolic blood pressure and urinary cedg. conclusion. dna oxidative and glycation damage-derived nucleoside adducts are increased in plasma and urine of patients with type 2 diabetes and further increased in patients with diabetic nephropathy. © 2015 sahar waris et al.