Ginger oil mediated down regulation of adipocyte specific genes inhibits adipogenesis and induces apoptosis in 3T3 L1 adipocytes
Dietary ginger is known to supress body weight gain and body fat accumulation. We investigated the effects of ginger oil on adipogenesis, proliferation, apoptosis and lipolysis of 3T3 L1 adipocytes. After treatment with ginger oil, adipocytes were stained with Oil Red O to visualize lipid droplets and then measured for lipid content. Mature adipocytes were treated with ginger oil (100 and 200 mg/ml) and the expression of adipocyte specific genes were investigated using real time RT PCR. Ginger oil inhibited adipogenesis and adipocyte proliferation as evidenced by dose dependent increase in apoptosis. Interestingly, the ginger oil effectively suppressed the expression of PPARg (peroxisome proliferator activated gamma) C/EBPa (CCAAT/enhancer binding protein alpha) and SREBP1c (sterol regulatory element binding protein 1c) and subsequently suppressed the expression of AKT1 (thymoma viral proto oncogene 1) gene, which inhibits proliferation and differentiation and induces apoptosis in adipocytes. It could also prevent obesity by inducing lipolysis via upregulation of expression of LIPE (gene for hormone sensitive lipase) and TNFa (tumor necrosis factor alpha) in mature adipocyte. In conclusion, ginger oil may alter fat mass by directly inhibiting adipogenesis and inducing apoptosis in adipocytes and therefore could have applications in the treatment of obesity.