Study of serum transforming growth factor-beta 1 (Tgf-β1) levels in type 2 diabetes mellitus patients with nephropathy.

Abstract

Background: Diabetic nephropathy (DN) is a major micro-vascular complication of diabetes mellitus (DM) and it is the leading cause of end stage renal disease (ESRD) worldwide. The present study was carried out to estimate the serum TGF-β1 levels in T2DM patients with nephropathy. Methodology: All study subjects (n=75) were enrolled in 3 groups. Group 1: (n=25) healthy controls, group 2: (n=25) T2DM patients without nephropathy, group 3: (n=25) T2DM patients with nephropathy. Patients were recruited from diabetic and nephrology clinic at University College of Medical Sciences and Guru Teg Bahadur Hospital, Delhi, India. Morning spot urine samples were collected for urine albumin and creatinine test. Serum and urine creatinine were estimated by alkaline picrate Jaffe´s kinetic method. Urine albumin was estimated by turbidometric method. Albumin/creatinine ratio (ACR) was expressed in mg/g creatinine. Serum TGF-β1 level was measured by ELISA kit. Results: A statistically significant difference was found in the levels of urinary ACR between the study groups I and III, II and III (p=0.000), but no statistically significant difference was found between groups I and II (p=0.460). There was a statistically significant difference observed in the serum TGF-β1 levels between the study groups I and II, I and III and II and III (p=0.000). Serum TGF-β1 showed significant positive correlation with HbA1c, fasting plasma glucose, post prandial plasma glucose, serum creatinine and urinary ACR. However, a negative correlation was found between serum TGF-β1 and eGFR. Conclusions: Serum TGF-β1 levels were found higher in patients with T2DM and were significantly elevated in T2DM patients with nephropathy. Serum TGF-β1 levels in diabetic patients were dependent on the glycemic control and degree of renal dysfunction however, its levels were not dependent on the duration of diabetes.