Tea Seed Saponin Combined with Aerobic Exercise Ameliorated Lipid Metabolism and Oxidative Stress in High-Fat Diet-Fed Mice

The effect of tea seed saponin (TSS) combined with aerobic exercise (AE) on lipid metabolism and oxidative stress in mice on a high-fat diet (HFD) was investigated.

Mice were randomly divided into a normal group and a model group. The normal group was fed on a maintenance diet and the model group on the HFD to establish an obesity model. After successful modeling, the mice were further divided into an HFD group, an HFD + TSS group, an HFD + AE group and an HFD + TSS-AE group. The levels of serum lipid metabolism and oxidative stress were determined by commercial kits. Hepatic steatosis was observed by hematoxylin-eosin (HE) staining. The protein levels of adenosine 5’-monophosphate (AMP)-activated protein kinase (AMPK), phosphorylated AMPK (p-AMPK), silent information regulator 1 (SIRT1), peroxisome proliferator-activated receptor γ coactlvator 1α (PGC-1α) and peroxisome proliferators-activated receptors γ (PPAR-γ) were detected by Western blot.

TSS combined with AE treatment significantly reduced body mass and subcutaneous, epididymal, perirenal and abdominal fat indexes in HFD mice (P < 0.05) and improved blood lipid disorders. The serum levels of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) were, respectively, reduced by 27.80%, 75.15%, 78.36% in the HFD + TSS + AE group compared with the HFD group. Hepatic steatosis was significantly improved in the HFD + TSS, HFD + AE and HFD + TSS-AE groups in comparison with the HFD group. The expression level of hepatic p-AMPK was increased by 64.19%, 2.12 times and 2.64 times, SIRT1 by 47.01%, 1.48% and 67.02%, PGC-1α by 2.03 times, 62.93% and 2.10 times, and PPAR-γ in skeletal muscle by 64.08%, 2.12 times and 3.34 times, respectively. After treated by TSS and AE, the serum and liver levels of superoxide dismutase (SOD) and glutathione (GSH) were increased in HFD mice, and serum malondialdehyde (MDA) levels were decreased.

TSS combined with AE can reduce fat accumulation and improve lipid metabolism disorders and oxidative stress induced by HFD in mice.