title: Ginsenoside Rg1 suppresses early stage of adipocyte development via activation of C/EBP homologous protein-10 in 3T3-L1 and attenuates fat accumulation in high fat diet-induced obese zebrafish.
abstract: BACKGROUND
  Ginsenoside Rg1 is a class of steroid glycoside and triterpene saponin inPanax ginseng. Many studies suggest that Rg1 suppresses adipocyte differentiation in 3T3-L1. However, the detail molecular mechanism of Rg1 on adipogenesis in 3T3-L1 is still not fully understood.
  
  
  METHODS
  3T3-L1 preadipocyte was used to evaluate the effect of Rg1 on adipocyte development in the differentiation in a stage-dependent mannerin vitro. Oil Red O staining and Nile red staining were conducted to measure intracellular lipid accumulation and superoxide production, respectively. We analyzed the protein expression using Western blotin vitro. The zebrafish model was used to investigate whether Rg1 suppresses the early stage of fat accumulationin vivo.
  
  
  RESULTS
  Rg1 decreased lipid accumulation in early-stage differentiation of 3T3-L1 compared with intermediate and later stages of adipocyte differentiation. Rg1 dramatically increased CAAT/enhancer binding protein (C/EBP) homologous protein-10 (CHOP10) and subsequently reduced the C/EBPβ transcriptional activity that prohibited the initiation of adipogenic marker expression as well as triglyceride synthase. Rg1 decreased the expression of extracellular signal-regulated kinase 1/2 and glycogen synthase kinase 3β, which are also essential for stimulating the expression of CEBPβ. Rg1 also reduced reactive oxygen species production because of the downregulated protein level of nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase 4 (NOX4). While Rg1 increased the endogenous antioxidant enzymes, it also dramatically decreased the accumulation of lipid and triglyceride in high fat diet-induced obese zebrafish.
  
  
  CONCLUSIONS
  We demonstrated that Rg1 suppresses early-stage differentiation via the activation of CHOP10 and attenuates fat accumulationin vivo. These results indicate that Rg1 might have the potential to reduce body fat accumulation in the early stage of obesity.
authors.affiliation: Department of Food Science and Biotechnology, College of Life Science, CHA University, Seongnam, Korea.
authors.forename: Eun-Jeong
authors.initials: EJ
authors.lastname: Koh
authors.affiliation: Department of Food Science and Biotechnology, College of Life Science, CHA University, Seongnam, Korea.
authors.forename: Kui-Jin
authors.initials: KJ
authors.lastname: Kim
authors.affiliation: Department of Food Science and Biotechnology, College of Life Science, CHA University, Seongnam, Korea.
authors.forename: Jia
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Food Science and Biotechnology, College of Life Science, CHA University, Seongnam, Korea.
authors.forename: Hui Jeon
authors.initials: HJ
authors.lastname: Jeon
authors.affiliation: Department of Food Science and Biotechnology, College of Life Science, CHA University, Seongnam, Korea.
authors.forename: Min-Jung
authors.initials: MJ
authors.lastname: Seo
authors.affiliation: Department of Food Science and Biotechnology, College of Life Science, CHA University, Seongnam, Korea.
authors.forename: Boo-Yong
authors.initials: BY
authors.lastname: Lee
keywords: 3T3-L1; CON, control; ND, nondifferentiated preadipocyte; Rg1; obesity; reactive oxygen species; zebrafish