Endocrine Abstracts

Visfatin, a protein secreted by the adipose tissue, might regulate insulin action. The aim of the present study was to assess serum visfatin concentration in obese women with normal glucose tolerance (NGT) and impaired glucose tolerance (IGT) and to estimate the relationships between serum visfatin concentration and insulin sensitivity, blood pressure, proinflammatory and proatherogenic factors.

The study group consisted of 134 women: 30 overweight or obese women with IGT (obese-IGT), 55 overweight or obese with NGT and 49 lean healthy controls. The oral glucose tolerance test was performed and the serum concentrations of visfatin, high-sensitive C-reactive protein (hsCRP) and soluble E-selectin (sE-selectin) were measured in all the subjects. Insulin sensitivity was estimated with euglycemic hyperinsulinemic clamp.

We observed the significantly lower insulin sensitivity and higher serum visfatin concentration in both groups of obese women in comparison to the control group (insulin sensitivity, obese-IGT, P<0.0001, obese-NGT, P=0.0027; serum visfatin, obese-IGT, P<0.0001 obese-NGT, P=0.016) and in obese-IGT in comparison to obese-NGT group (insulin sensitivity, P<0.0001; serum visfatin, P=0.0055). In the whole studied group, serum visfatin concentration was negatively related to insulin sensitivity (r=−0.29, P=0.001) and HDL-cholesterol (r=−0.32, P=0.00015) and positively related to systolic and diastolic blood pressure (r=0.33, P<0.0001 and r=0.32, P=0.00016, respectively), fasting and postload glucose (r=0.25, p=0.003 and r=0.31, P=0.00025, respectively), fasting insulin (r=0.20, P=0.028), serum triglycerides (r=0.27, P=0.001), hsCRP (r=0.25, P=0.005) and sE-selectin (r=0.33, P=0.00013). In multiple regression analysis, the relationships between serum visfatin and systolic and diastolic blood pressure, and sE-selectin were independent of BMI and insulin sensitivity.

Increased serum visfatin concentration in obesity and IGT is associated with insulin resistance, blood pressure and proinflammatory factors and thus could be linked to an increased risk of type 2 diabetes and cardiovascular disease.