Endocrine Abstracts

Markers of endothelial dysfunction, including soluble E-selectin (sE-selectin) are related to insulin resistance and are predictors of type 2 diabetes. Insulin resistance is associated with metabolic inflexibility, i.e. an impaired stimulation of carbohydrate oxidation and inhibition of lipid oxidation in insulin-stimulated conditions. The aim of the present study was to estimate the relationships of serum sE-selectin concentration with carbohydrate and lipid oxidation in lean and obese women. The study group consisted of 80 apparently healthy women: 33 lean and 47 with overweight or obesity. Euglycemic hyperinsulinemic clamp and indirect calorimetry in the baseline state and during the last 30 minutes of the clamp were performed. Obese women had lower insulin sensitivity (P=0.0022) and higher serum sE-selectin concentration (P=0.034). In the obese group, carbohydrate oxidation was increased in baseline state (P=0.019) and decreased during hyperinsulinemia (P=0.048) and lipid oxidation was higher during hyperinsulinemia (P=0.0012). Obese women had also lower increase in carbohydrate oxidation (P=0.0012) and lower decrease in lipid oxidation (P=0.034) during the clamp. Serum sE-selectin was negatively related to insulin sensitivity (r=−0.27, P=0.015). Higher serum sE-selectin concentration was associated with a lower increase in carbohydrate oxidation (r=−0.41, P<0.001) and a lower decrease in lipid oxidation (r=0.29, P=0.008) during the clamp. Serum sE-selectin was also inversely related to the direct measure of metabolic flexibility, i.e. to an increase in respiratory quotient in response to insulin (r=−0.36, P=0.001). Our data show that serum sE-selectin concentration is associated with both carbohydrate and lipid oxidation. Higher serum sE-selectin concentration might be linked to metabolic inflexibility of obesity and insulin resistance.