Lipid metabolic effect of Korean red ginseng extract in mice fed on a high-fat diet

BACKGROUND: Ginseng saponin and ginsenosides exert anti-obesity effects via the modulation of physiological lipid metabolism in vivo or intracellular signalling in cell culture systems. However, the complicated relationship between the anti-obesity effects of ginseng and gene expression has yet to be defined under in vivo conditions. Therefore, we evaluated the relationship between the anti-obesity effects of Korean red ginseng extract (KRGE) and hepatic gene expression profiles in mice fed long-term on a high-fat diet (HFD) in this study. RESULTS: KRGE reduces the levels of cholesterol, low- density lipoprotein- cholesterol (LDL- C), serum triglycerides, and atherogenic indices. Levels of leptin, adiponectin and insulin, which regulate glucose and lipid metabolism, were impaired profoundly by HFD. However, KRGE treatment brought these levels back to normal. KRGE was found to down- regulate genes associated with lipid metabolism or cholesterol metabolism (Lipa, Cyp7a1, Il1rn, Acot2, Mogat1, Osbpl3, Asah3l, Insig1, Anxa2, Vldlr, Hmgcs1, Sytl4, Plscr4, Pla2g4e, Slc27a3, Enpp6), all of which were up- regulated by HFD. CONCLUSION: KRGE regulated the expression of genes associated with abnormal physiology via HFD. Leptin, insulin, and adiponectin, which carry out critical functions in energy and lipid metabolism, were shown to be modulated by KRGE. These results show that KRGE is effective in preventing obesity. (C) 2011 Society of Chemical Industry