Fermented Platycodon grandiflorum Extract Inhibits Lipid Accumulation in 3T3-L1 Adipocytes and High-Fat Diet-Induced Obese Mice

The aim of this study was to investigate whether fermented Platycodon grandiflorum (FPG) inhibits lipid accumulation in 3T3-L1 adipocytes and mice with high-fat diet (HFD)-induced obesity. We evaluated the effect of FPG on antiadipogenic activity via regulation of peroxisome proliferator-activated receptor gamma (PPAR gamma) and CCAAT/enhancer-binding protein alpha (C/EBP alpha), as well as protein expression of their target genes, fatty acid binding protein 4 (FABP4). We further examined the antiobesity effects of FPG on HFD-induced obesity in mice. The FPG was orally administered to mice with a HFD at 50, 100, or 200 mg/kg/day for 8 weeks. Our results show that FPG significantly inhibited fat accumulation during 3T3-L1 adipogenesis through downregulating adipogenic transcript factors. Moreover, FPG markedly reduced the final body weight with a decrease in epididymal adipose tissue mass and adipocyte size compared with the untreated HFD-induced group. The effects of FPG on HFD-induced obesity were primarily responsible for inhibiting adipogenesis in adipose tissue and regulating lipid metabolism, such as through lipogenesis and fatty acid oxidation. Additionally, FPG ameliorated serum total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels. Hence, FPG may be an alternative treatment for controlling obesity through downregulating lipid accumulation.