The Influence of Insulin on the Raised Plasma Fibronectin Concentration in Human Obesity

ABSTRACT Plasma concentrations of fibronectin, free insulin, C-peptide and plasma glucose were determined in 40 morbidly obese subjects and in 51 normal weight controls, matched for sex and age. All plasma concentrations were significantly elevated (p<0.01) among the obese subjects. A significant correlation (r=0.34, p<0.05) between plasma fibronectin and plasma free insulin was found among the obese patients, but not among the controls (r=-0.02, p>0.05). No significant correlation was found between plasma fibronectin and plasma C-peptide, neither in the obese patients nor in the controls (obese r=0.06, controls r=0.02; p>0.05). Plasma fibronectin was insignificantly correlated with body weight (obese r=0.21, controls r=0.15; p>0.05) and percentage overweight (obese r=0.27, controls r=0.04; p>0.05). The raised level of circulating insulin may in part explain the excess of plasma fibronectin of obese subjects.