Increased Fasting Plasma Retinol-binding Protein-4 (Rbp4) Associates with Impaired Glucose Tolerant Subjects Visited in a Tertiary Hospital of Bangladesh

Abstract

Animal studies have been suggested that Retinol-binding Protein-4 (RBP4) associates in the development of type 2 diabetes (T2D) but human studies are still controversial. Therefore, the present study aims to investigate plasma RBP4 in subjects with Impaired Fasting Glucose (IFG) and Impaired Glucose Tolerance (IGT) whether its changes commences before the onset of T2D. This study has investigated 13 IFG, 43 IGT and 16 IFG-IGT along with 50 healthy subjects. Fasting insulin and RBP4 were measured using Enzyme-Linked Immunosorbent Assay (ELISA) technique. Insulin sensitivity (HOMA %S) and insulin secretory capacity (HOMA %B) were estimated using fasting plasma glucose and fasting insulin values through HOMA-CIGMA software. Fasting plasmaRBP4 (ng/ml) level was significantly higher in IGT and IFG-IGT subjects compared to controls. In binary logistic regression analysis RBP4 was found to be significantly associated with IGT (B=0.123, p=0.001) and IFG-IGT subject (B=0.146, p=0.012). RBP4 was found to be significantly correlated with thewaist-hip ratio (r=0.323, p=0.035), fasting insulin (r=0.338, p=0.027) and HOMA-IR (r=0.336, p=0.037) in IGT subjects; after adjusted the effects of age and BMI, RBP4 has still associated with IR in IGT (B=0.400, p=0.009). The above results could be concluded as a) RBP4 has been increased in IGT and IFG-IGT subjects; b) RBP4 is positively associated with insulin resistance (IR) in IGT subjects.