Obesity-related nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Exercise and diet are uniformly prescribed treatments for NAFLD, however there are limited empirical data on the effects of exercise training on metabolic function in these patients. The purpose of this study was to investigate the effect of short-term aerobic exercise training on gut peptides (glucagon-like peptide-1 (GLP-17-36) and peptide tyrosine tyrosine (PYYTotal)) in patients with NAFLD. Twenty-two obese subjects, 16 with NAFLD (BMI, 33.2±1.1 kg/m2), and 6 obese-matched Controls (BMI, 31.3±1.2 kg/m2) were enrolled in a supervised aerobic exercise program (60 min/day, 85% HRmax for 7 days). Fasting, and PYY and GLP-1 responses to oral glucose stimulation were assessed at baseline and after the exercise program. Initially, the NAFLD group was more insulin resistant, had higher fasting PYY and GLP-1 (P<0.05), and based on the initial 0-30 min response displayed a blunted PYY and GLP-1 reaction to glucose. After the exercise program, insulin sensitivity was increased and fasting GLP-1 was reduced in the NAFLD group (P<0.05), and the GLP-1 tAUC120 response to glucose was reduced in both NAFLD and Controls. Notably, exercise training led to a significant increase in the dynamic PYY and GLP-1 responses to glucose in the NAFLD group. In summary, seven days of vigorous aerobic exercise essentially normalized the dynamic PYY and total GLP-1 responses to nutrient stimulation in subjects with NAFLD. These data suggest that exercise improves important modulators of satiety and metabolism and could help to alleviate NAFLD in obese patients.
- fatty liver disease
- insulin resistance
- physical activity
- Copyright © 2015, Journal of Applied Physiology