title: Polyunsaturated fatty acid regulation of adipocyte FADS1 and FADS2 expression and function.
abstract: OBJECTIVE
  Polyunsaturated fatty acids (PUFAs) regulate fatty acid desaturase (FADS1, FADS2) expression in the liver; however, it is unknown whether PUFAs regulate FADS in adipocytes. This is important to study considering reports that link altered desaturase activity with adipose tissue PUFA profiles, body weight, and whole-body glucose homeostasis. Therefore, the present study aimed to determine the direct effects of PUFAs on FADS expression in differentiated 3T3-L1 adipocytes.
  
  
  METHODS
  Differentiated 3T3-L1 adipocytes were treated with either α-linolenic (ALA), linoleic (LA), eicosapentaenoic (EPA), or arachidonic acid (AA). Gene expression, protein abundance, and cellular PUFA content were analyzed by real-time RT-PCR, Western blotting, and gas chromatography, respectively.
  
  
  RESULTS
  Fads1 and Fads2 gene expression was reduced by EPA and AA, but not ALA or LA. Reductions in gene expression were reflected in FADS2 protein levels, but not FADS1. Treating cells with ALA and LA led to significant increases in the cellular content of downstream PUFAs. Neither ALA nor EPA changed docosahexaenoic acid content.
  
  
  CONCLUSIONS
  Differentiated 3T3-L1 adipocytes have a functional FADS pathway that can be regulated by PUFA. Therefore, this common adipocyte model is suitable to study dietary regulation of the FADS pathway.
authors.affiliation: Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada.
authors.forename: Jessica C
authors.initials: JC
authors.lastname: Ralston
authors.forename: Sarthak
authors.initials: S
authors.lastname: Matravadia
authors.forename: Nicholas
authors.initials: N
authors.lastname: Gaudio
authors.forename: Graham P
authors.initials: GP
authors.lastname: Holloway
authors.forename: David M
authors.initials: DM
authors.lastname: Mutch
mesh_terms: D041721:3T3-L1 Cells; D017667:Adipocytes / Q000378:metabolism*; D000818:Animals; D016718:Arachidonic Acid / Q000235:genetics; D000090943:Delta-5 Fatty Acid Desaturase; D004281:Docosahexaenoic Acids; D044943:Fatty Acid Desaturases / Q000235:genetics* / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000235:genetics* / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D051379:Mice; D020641:Polymorphism, Single Nucleotide
chemical_list: D000090943:Delta-5 Fatty Acid Desaturase; D005231:Fatty Acids, Unsaturated; D004281:Docosahexaenoic Acids; D016718:Arachidonic Acid; D044943:Fatty Acid Desaturases; C000716847:FADS1 protein, human; C533241:FADS2 protein, human