title: Expression and modulation of ghrelin O-acyltransferase in cultured chondrocytes.
abstract: OBJECTIVE
  To use reverse transcription-polymerase chain reaction to detect ghrelin O-acyltransferase (GOAT) transcripts in both murine and human chondrocytes, to evaluate the effect of pharmacologic in vitro treatments with lipopolysaccharide (LPS), growth hormone, ghrelin, and dexamethasone on GOAT messenger RNA (mRNA) expression, and to study the GOAT mRNA profile during chondrocyte differentiation.
  
  
  METHODS
  Murine and human GOAT and ghrelin mRNA levels were determined by the SYBR Green-based quantitative real-time polymerase chain reaction method.
  
  
  RESULTS
  GOAT mRNA was expressed in murine cartilage explants as well as in the cultured murine chondrogenic ATDC-5 cell line. GOAT was also expressed in human immortalized chondrocyte cell lines and in human cultured primary chondrocytes. In addition, GOAT mRNA expression in differentiating ATDC-5 cells was lower at the early stage of differentiation (days 3-7), whereas GOAT mRNA levels increased progressively at the late stages. Finally, among the drugs and hormones tested, only LPS was able to strongly decrease GOAT mRNA expression.
  
  
  CONCLUSIONS
  These data indicate that chondrocytes are equipped with biochemical machinery for the synthesis of acylated ghrelin and suggest a novel role of the ghrelin axis in prehypertrophic and hypertrophic chondrocyte differentiation during endochondral ossification.
authors.affiliation: Santiago University Clinical Hospital, Santiago University School of Medicine, Santiago de Compostela, Spain.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Gómez
authors.forename: Francisca
authors.initials: F
authors.lastname: Lago
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Gómez-Reino
authors.forename: Carlos
authors.initials: C
authors.lastname: Dieguez
authors.forename: Oreste
authors.initials: O
authors.lastname: Gualillo
mesh_terms: D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D002460:Cell Line; D019902:Chondrocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D003907:Dexamethasone / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D054439:Ghrelin / Q000378:metabolism / Q000494:pharmacology; D013006:Growth Hormone / Q000494:pharmacology; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D008565:Membrane Proteins; D051379:Mice; D023421:Models, Animal; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D054439:Ghrelin; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D012333:RNA, Messenger; D003907:Dexamethasone; D013006:Growth Hormone; D000217:Acyltransferases; C542776:MBOAT4 protein, human; C526983:Mboat4 protein, mouse