The effect of acute exercise on circulating serum retinol binding protein 4 in seniors with and without impaired glucose tolerance (863.4)

Retinol binding protein 4 (RBP4) is an adipokine that contributes to insulin resistance and impaired glucose tolerance. There are no published reports concerning the influence of acute exercise on circulating RBP4. We sought to characterize this response in (1) healthy, normoglycemic males (CON; 23±4 y, BMI 22.3±9.4), (2) seniors with normal fasting glucose and glucose tolerance (S-NGT; 70±5 y, BMI 24.2±6.5), and (3) seniors with impaired glucose tolerance (S-IGT; 73±8 y, BMI 26.4±5.3; n=7 per group). Glucose tolerance was based on a 75 g oral glucose tolerance test wherein 2 h glucose values (mg/dL) were: 97±21 (CON), 106±24 (S-NGT), and 159±13 (S-IGT; p<0.05 vs. CON and S-NGT). 48 h after determining VO2max (ml/kg/min) in CON (56±10, p<0.05 vs. S-NGT and S-IGT), S-NGT (33±8), and S-IGT (29±8) subjects, participants completed 20-min of cycling at 85% VO2max. RBP4 was assessed (ELISA) in venous samples obtained before exercise and 50-min and 24 h post exercise. Pre-exercise RBP4 concentrations (ug/mL) wer...