Platycodon grandiflorum extract represses up-regulated adipocyte fatty acid binding protein triggered by a high fat feeding in obese rats

AIM: To investigate the effect of Platycodon grandiflorum extract (PGE) on lipid metabolism and FABP mRNA expression in subcutaneous adipose tissue of high fat diet-induced obese rats. METHODS: PGE was treated to investigate the inhibitory effect on the pre-adipocyte 3T3-L1 differentiation and pancreatic lipase activity. Male Sprague-Dawley rats with an average weight of 439.03 +/- 7.61 g were divided into four groups: the control groups that fed an experimental diet alone (C and H group) and PGE treatment groups that administered PGE along with a control diet or HFD at a concentration of 150 mg/kg body weight (C + PGE and H + PGE group, respectively) for 7 wk. Plasma total cholesterol (TC) and triglycerol (TG) concentrations were measured from the tail vein of rats. Adipocyte cell area was measured from subcutaneous adipose tissue and the fatty acid binding protein (FABP) mRNA expression was analyzed by northern blot analysis. RESULTS: PGE treatment inhibited 3T3-L1 pre-adipocyte differentiation and fat accumulation, and also decreased pancreatic lipase activity. In this experiment, PGE significantly reduced plasma TC and TG concentrations as well as body weight and subcutaneous adipose tissue weight. PGE also significantly decreased the size of subcutaneous adipocytes. Furthermore, it significantly repressed the up-regulation of FABP mRNA expression induced by a high-fat feeding in subcutaneous adipose tissue. CONCLUSION: PGE has a plasma lipid lowering-effect and anti-obesity effect in obese rats fed a high fat diet. From these results, we can suggest the possibility that PGE can be used as a food ingredient or drug component to therapeutically control obesity.