<i>Glehnia littoralis</i> Root Extract Inhibits Fat Accumulation in 3T3‐L1 Cells and High‐Fat Diet‐Induced Obese Mice by Downregulating Adipogenic Gene Expression

Abstract

<i>Glehnia littoralis</i> has been reported to have several pharmacological properties but no reports describing the antiadipogenic effect of this plant have been published. This study was conducted to investigate the effects of <i>Glehnia littoralis</i> root hot water extract (GLE) and its underlying mechanism on 3T3-L1 cell adipogenesis and in high-fat diet- (HFD-) induced obese mice. We measured intracellular lipid accumulation using oil red O staining <i>in vitro</i>. For <i>in vivo</i> study, twenty-eight C57BL/6J male mice were randomly divided into four groups, Control, HFD, HFD + 1% GLE, and HFD + 5% GLE, which was performed for eight weeks. We determined the expression levels of the adipogenesis-related proteins by RT-PCR and western blotting in HFD-induced obese mice. The GLE dose-dependently inhibited 3T3-L1 adipocyte differentiation and intracellular lipid accumulation in differentiated adipocytes. Further, body weight gain and fat accumulation were significantly lower in the GLE-treated HFD mice than in the untreated HFD mice. GLE treatment suppressed the expression of adipogenic genes such as peroxisome proliferator-activated receptor (PPAR) <i>γ</i>, CCAAT/enhancer-binding protein (C/EBP) <i>α</i>, fatty acid synthase (aP2), and fatty acid synthase (FAS). These results suggest that the GLE inhibits adipocyte differentiation and intracellular lipid accumulation by downregulating the adipogenic gene expression both <i>in vitro</i> and <i>in vivo</i>.