Relationship of serum resistin level with insulin resistance indices in non-diabetic and diabetic obese subjects

Abstract

Background: Resistin, an adipocyte secreted factor, has been suggested to link obesity with type 2 diabetes and insulin resistance in rodent models but its relevance to human diabetes remains uncertain. The aim of this study was to investigate the relationship between serum resistin concentrations with insulin resistance and obesity indices in type 2 diabetes and non-diabetic obese subjects. Methods: As a case- control study 35 obese subjects with type 2 diabetes (age, 44.60 آ± 6.39yr; BMI 34.23آ±3.92 kg/m2) and 35 obese non-diabetics (age, 43.14آ±9.13yr; BMI, 35.54 آ±4.07 kg/m2) are recruited. Fasting lipid profile was measured by enzymatic methods. NycoCard HbA1c Kit was used to measure HbA1c. The Serum resistin, insulin and glucose levels were measured by an enzyme immunoassay using a commercially available kit and glucose oxidase methods respectively. The insulin resistance index was calculated from fasting glucose and insulin by the homeostasis model assessment (HOMA-IR) formula. Results: The mean of insulin resistance index (HOMA-IR), HbA1c, diastolic blood pressure, triglyceride and fasting glucose in diabetics were significantly higher than non-diabetics subjects (P<0.05). Serum resistin concentrations were not different between diabetics and non-diabetics obese subjects but were significantly higher in women as compared to men (8.15آ±4.40 vs. 5.97آ±2.31 in non-diabetic) and (7.46آ±3.98 vs. 5.51آ±3.98 in diabetic) in both groups. Serum resistin was not significantly related to variables measured in both groups. In control group only, we observed a significant and negative correlation between diastolic blood pressure and resistin (r = -0.381 ; P = 0.024). Conclusion: Serum resistin concentrations were not significantly different between type 2 diabetes and non-diabetic obese subjects and resistin is unlikely to be a major link between obesity and diabetes in humans.