Association of Serum Telomerase Activity in Type 2 Diabetes Mellitus Patients with or without Microalbuminuria

Abstract

BACKGROUND Telomerase is an enzyme which helps in maintaining the length of the telomeres. Various studies have associated the telomere length and serum telomerase activity with ageing, insulin resistance and obesity. The metabolic disease type 2 diabetes mellitus is also associated with premature ageing, obesity, insulin resistance. Urine microalbuminuria is one of the frequently used markers to assess renal involvement in non-insulin dependent type 2 diabetes patients. Hence, this study was conducted to estimate the association of serum telomerase activity, a marker of aging and its association with urine microalbuminuria in non-insulin dependent type 2 diabetes patients with or without renal involvement. METHODS The study included 180 non-insulin dependent type 2 diabetes patients divided into two groups – Group I without microalbuminuria; Group II with microalbuminuria and 90 age and sex matched healthy volunteers as control population of the study. The sample size was determined at conveniences. Fasting blood sugar, lipid profile, serum urea, creatinine was estimated by autoanalyser, glycated haemoglobin by high performance liquid chromatography (HPLC) and serum telomerase activity were measured by enzyme-linked immunosorbent assay (ELISA) method. Urinary microalbuminuria was measured by immunoturbidimetry. The data was compared by one-way analysis of variance (ANOVA) and post hoc Tukey’s honestly significant difference (HSD) test, linear regression analysis and Pearson correlation analysis. RESULTS Non-insulin dependent type 2 diabetes patients with microalbuminuria had significantly lower telomerase activity and higher glycated haemoglobin, dyslipidaemia, increased serum urea and creatinine levels as compared to the group I diabetes mellitus patients and healthy volunteers. The serum telomerase level exhibited a negative correlation with urinary microalbuminuria, glycated hemoglobin and serum triglyceride and BMI. CONCLUSIONS Low Serum Telomerase is associated with microalbuminuria, obesity and poor glycaemic control in non-insulin dependent type 2 diabetes mellitus patients, indicating the possible existence of a common clinical profile and premature aging among diabetic patients with chronic kidney disease. Early screening for microalbuminuria and serum telomerase level may assist management of positive cases and reduce the load of chronic renal disease and coronary artery disease in type 2 diabetes patients. Validation of our observations may be done by extending the study in larger population thereby facilitating the understanding of T2DM pathophysiology and its complications. KEYWORDS Diabetes Mellitus, Glycated Haemoglobin, Microalbuminuria, Telomerase