Short‐term aerobic exercise improves hepatic lipid composition, insulin sensitivity, and circulating HMW adiponectin independent of weight loss in patients with non‐alcoholic fatty liver disease

Abstract

Hepatic steatosis, insulin resistance, inflammation, and low levels of polyunsaturated lipids and adiponectin are implicated in the development and progression of non-alcoholic fatty liver disease (NAFLD). We examined the effects of short-term aerobic exercise on these metabolic risk factors. Obese individuals (n=15, 34.7±1.0 kg/m2) with diagnosed NAFLD were enrolled in a short-term aerobic exercise program that consisted of 7 consecutive days of treadmill walking at 85% HRmax for 60 min/d. Pre- and post-exercise measures consisted of hepatic triglyceride content, lipid saturation index (SI) and polyunsaturated lipid index (PUI) of the liver via 1H MR spectroscopy and glucose tolerance was determined by OGTT. Mononuclear cells were isolated for reactive oxygen species (ROS) production during the OGTT, and glucose, insulin, and adiponectin were determined from plasma. Exercise training resulted in an 84% increase in the PUI (p=0.01), and increases in insulin sensitivity (Matsuda Index: p=0.04), HMW adiponectin (p=0.02) and VO2max. ROS production was reduced following exercise training (p=0.04). HMW adiponectin changes were positively correlated with changes in liver PUI (R=0.713, p=0.01). These data suggest that exercise alone can augment metabolic risk factors associated with NAFLD progression and that these changes may be driven by increases in adiponectin. Support: CTSA UL1 RR024989, HL007887