Aerobic Training Decrease Body Fat may via Zinc Alpha2 Glycoprotein

Abstract

Previous studies have reported that aerobic training reduces body fat content. Zinc alpha2 glycoprotein (ZAG), a lipid mobilizing factor, is negatively correlated with fat mass. The function of ZAG is associated with reduced fatty acid synthase (FAS) expression and increased hormone-sensitive lipase (HSL) expression in liver of obese mice. We hypothesized that aerobic training up-regulate the expression of ZAG, leading to reduction of body fat. PURPOSE: To determine the underlying association between aerobic training and the expression of ZAG. METHODS: High-fat-diet (HFD)-induced obese mice were divided into two groups, control group (C, n=10) and aerobic training group (T, n=10). Training protocol is 8 weeks moderate intensity treadmill running (10m/min for the first four weeks, 12m/min for the last four weeks, 60min/day, 5 days/week). Measure the body weight twice a week. After 8 weeks intervention experiment, , all animals were sacrificed following overnight fasting, the visceral adipose tissue were dissected and weighed, and liver tissue were excised and homogenized. ZAG, FAS and HSL mRNA expression were detected by PCR technique. Data were analyzed by student’s t-test, with statistical significance being set at p ≤ 0.05. RESULTS: Aerobic training decrease body weight (C,76.80±7.13g vs. T,69.50±3.64g, p<0.05), and also reduce visceral adipose weight (C,5.14±1.29g vs.T,2.81±1.53g, p<0.05). Aerobic training increase ZAG mRNA expression in adipose tissue (C,1.26±0.31 vs. T,2.53±0.58,p<0.05) , but it doesn’t change in liver (C,0.95±0.24 vs.T,0.99±0.29,p>0.05). FAS expression in liver decreased (C,0.037±0.016 vs. T,0.106±0.006, p<0.05), HSL expression in liver slightly increased (C,0.0078±0.0017 vs. T,0.0087±0.0024, p>0.05). CONCLUSION: These indicated that aerobic training may increase ZAG mRNA expression in adipose tissue, and ZAG prohibits fat synthesis through decrease FAS mRNA expression. Aerobic training decrease body fat may via ZAG, but the detail mechanism requires future trials to confirm.