Effect and Mechanism of Andrias davidianus Peptide Supplementation Combined with Treadmill Exercise on Body Mass Loss in Obese Rats

To evaluate the antiobesity effect and underlying mechanism of Andrias davidianus peptide (ADP) supplementation combined with treadmill exercise.

A mouse model of obesity was established by feeding mice a high-fat diet (HFD), and the obese mice were randomly divided into four groups: model, treadmill exercise (Ex), ADP and ADP combined with treadmill exercise (ADP + Ex). The rats in the Ex group were subjected to a six-week treadmill exercise training. The rates in the ADP group were gavaged with ADP for six weeks. The rats in the ADP + Ex group were treated with ADP supplementation combined with treadmill exercise training. Normal Sprague Dawley (SD) rats were used as the control (CN) group. Body mass and food intake were recorded each week, and the serum levels of glucagon-like peptide-1 (GLP-1), neuropeptide Y (NPY), irisin, leptin, triglycerides (TG), total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) were investigated by enzyme-linked immunosorbent assay (ELISA). Western blot was used to detect the expression of appetite-regulated proteins (NPY and proopiomelanocortin (POMC)) and energy metabolism-related proteins.

Body mass, inguinal and epididymal fat accumulation, food intake, and serum TG, TC and LDL levels significantly decreased in the ADP + Ex group compared with the model group. In addition, ELISA results revealed that combination of ADP supplementation with treadmill exercise reduced the serum levels of NPY and leptin but increased the serum concentrations of GLP-1 and irisin in obese rats. Western blot analysis showed that ADP supplementation combined with treadmill exercise greatly up-regulated the expression of POMC and energy metabolism related proteins (irisin, phospho-adenosine monophosphate-activated protein kinase, peroxisome proliferator-activated receptor γ co-activated factor-1α, and fibronectin type Ⅲ domain containing protein 5), but down-regulated the expression of NPY.

The combination of ADP with aerobic exercise can effectively alleviate HFD-induced obesity, thereby providing a new promising strategy to alleviate HFD-induced obesity.