Association of relative telomere length with progression of diabetic nephropathy in Egyptians

Abstract

Diabetic nephropathy in type 1 diabetic (T1D) patients is the one cause of increased mortality and morbidity compared with normoalbuminuric patients. Telomere length in proliferative cells is inversely related to the total number of cell divisions in age related disease. This study was constructed to assess the telomere length (TL) and some oxidative markers as predictor markers of diabetic nephropathy (DN) in T1D patients. Ninety one volunteers (males), their ages range between (15-35) years old, were enrolled in this study and classified as follows: Group (1): consisted of 20 normal subjects (control). Group (2): Included 20 hypertensive patients. Group (3): Included 20 normotensive T1D patients (AER ≤ 30mg /g). Group (4): Included 30 hypertensive T1D patients (AER: 30-300mg/g), (DN), which divided into the following sub groups: Group (4a): Included 15 patients with microalbuminuria (30mg/g ≥ AER ≤ 300mg/g) and Group (4b): Included 15 patients with macroalbuminuria (AER ≥ 300mg/g). Leukocyte telomere length (LTL) ratio (T/S ratio) and telomere length (TL) were measured using a quantitative PCR. Renal and glycemic biomarkers were estimated, also malondialdehyed (MDA), 8-hydroxy deoxy guanosine (8-OhdG) and transforming growth factor β1 (TGF-β1) were measured. The results of the present study revealed that, T/S ratio and TL were significantly shorter in hypertension and T1D groups. This shorting was significantly increased in group 4 compared with control group. 8-OhdG, MDA and TGF- β1 were significantly increased in all studied groups compared with control group. A significant positive correlation was recorded between 8-OhdG and AER in DN group. In contrast, it was noted that TL was negatively correlate with 8-OhdG and HbA1c in all patient groups. The results obtained indicates that TL shortening is independent predictor of development and