Differences in plasma apelin and visfatin levels between patients with type 1 diabetes mellitus and healthy subjects and response after acute hyperglycemia and insulin administration

OBJECTIVE. Previous data suggest that apelin and visfatin play a role in metabolism and glucose homeostasis. The aim of the present study was to determine differences in plasma apelin and visfatin concentrations between healthy subjects and patients with type 1 diabetes mellitus and to study the effect of hyperglycemia and insulin administration on their levels in patients with type 1 diabetes mellitus. DESIGN. One hundred patients with T1DM and 52 healthy subjects were examined. Nine patients with type 1 diabetes and 9 controls participated in a further study. In the main study, blood samples were taken after a 12-hour fast. In a further study, an oral glucose tolerance test was performed on two occasions. In session A, at baseline, insulin lispro (7 units) was administered subcutaneously to the type 1 diabetic patients, while a placebo injection was administered to controls. In session B, no insulin or placebo was administered. Apelin, visfatin, insulin and glucose levels were measured at baseline and 10, 20, 30, 60, 90, 120, 150 and 180 min after glucose consumption. RESULTS AND CONCLUSIONS. Fasting plasma apelin concentrations were higher (p<0.001), while fasting visfatin levels tended to be lower (p=0.06) in patients with type 1 diabetes in comparison to healthy subjects. In the diabetes group, fasting apelin (but not visfatin) correlated with HDL-C (p=0.001). Apelin and visfatin did not change significantly during the oral glucose tolerance test in either group with or without exogenous insulin administration.