title: Germacrone inhibits adipogenesis and stimulates lipolysis via the AMP-activated protein kinase signalling pathway in 3T3-L1 preadipocytes.
abstract: OBJECTIVE
  In a previous study, we reported that Aster spathulifolius Maxim extract (ASE) inhibited lipid accumulation and adipocyte differentiation in 3T3-L1 cells. Of the components in ASE, germacrone (GM) was identified as a potent bioactive constituent. GM is known for its anticancer and antiviral activity. However, the effects of GM and the molecular mechanism by which GM regulates adipogenesis and lipolysis were not reported. Therefore, we investigated the effect of GM on adipogenesis and lipolysis and to elucidate its underlying molecular mechanism.
  
  
  METHODS
  We analysed the contents of intracellular triglyceride and carried out Western blotting and RT-qPCR to investigate the underlying mechanism.
  
  
  RESULTS
  We demonstrate that GM suppresses adipogenic differentiation and the increase in lipolysis in 3T3-L1 cells. In particular, GM down-regulates the expression of early adipogenesis-related genes (e.g. KLF4, KLF5, C/EBP-β and C/EBP-δ) and major adipogenesis-related genes (C/EBP-α and PPAR-γ). Furthermore, GM increases the protein levels of phosphorylated AMP-activated protein kinase α (AMPKα), phosphorylated acetyl-coenzyme A carboxylase (ACC) and carnitine palmitoyltransferase (CPT1).
  
  
  CONCLUSIONS
  Our results suggest that GM may be a potent bioactive anti-adipogenic and lipolytic constituent via the regulation of adipogenesis, lipolysis and the AMPKα pathway.
authors.affiliation: Department of Preventive Pharmacy and Toxicology, College of Pharmacy, Kyung Hee University, Seoul, Korea.
authors.forename: Yuan-Ri
authors.initials: YR
authors.lastname: Guo
authors.affiliation: Department of Preventive Pharmacy and Toxicology, College of Pharmacy, Kyung Hee University, Seoul, Korea.|Department of Life and Nanopharmaceutical Sciences, Graduate School, Kyung Hee University, Seoul, Korea.
authors.forename: Se-Young
authors.initials: SY
authors.lastname: Choung
mesh_terms: D041721:3T3-L1 Cells; D055372:AMP-Activated Protein Kinases / Q000378:metabolism*; D000103:Acetyl-CoA Carboxylase / Q000378:metabolism; D017667:Adipocytes / Q000378:metabolism*; D050156:Adipogenesis / Q000187:drug effects*; D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015536:Down-Regulation / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects; D000090062:Kruppel-Like Factor 4; D008066:Lipolysis / Q000187:drug effects*; D051379:Mice; D045788:Sesquiterpenes, Germacrane / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D014280:Triglycerides / Q000378:metabolism
chemical_list: C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D045788:Sesquiterpenes, Germacrane; D014280:Triglycerides; C048393:germacrone; D002334:Carnitine O-Palmitoyltransferase; C548179:Prkaa1 protein, mouse; D055372:AMP-Activated Protein Kinases; C498191:Acacb protein, mouse; D000103:Acetyl-CoA Carboxylase
keywords: 3T3-L1 cells; AMP-activated protein kinase α; adipogenesis; germacrone; lipolysis