Serum visfatin is differentially regulated by insulin and free fatty acids in healthy men

Abstract

Context: Serum visfatin is elevated in insulin-resistant states, ie, obesity, type 2 diabetes mellitus, and polycystic ovary syndrome, thus linking visfatin with the pathogenesis of insulin resistance. Objective: Our objective was to evaluate the effect of hyperinsulinemia and the acute elevation of free fatty acids (FFAs) on serum visfatin in humans. Design, Setting and Subjects: We estimated serum visfatin during hyperinsulinemia and the insulin- resistant conditions caused by an acute elevation of FFAs in 19 healthy male volunteers (mean age, 25 ± 7 years; body mass index, 26 ± 4 kg/m2) at a university hospital. Interventions: Intervention included a 6-hour euglycemic-hyperinsulinemic clamp without and with Intralipid/heparin infusion. Main Outcome Measures: Measurements were made of serum visfatin at baseline and at 2 and 6 hours during both clamp studies. Results: Hyperinsulinemia resulted in a significant decrease in serum visfatin concentration (P = .043). Concomitant Intralipid/heparin infusion, which caused a reduction of insulin sensitivity by 40% (P < .0001), resulted in a marked increase in serum visfatin (P < .0001), which was already observed after 2 hours of FFAs increase (P