title: Fluoride reduces the expression of enamel proteins and cytokines in an ameloblast-derived cell line.
abstract: OBJECTIVE
  To investigate the effects of two different fluoride concentrations on the expression of enamel proteins, alkaline phosphatase (ALP), cytokines and interleukins by an ameloblast-derived cell line.
  
  
  METHODS
  Murine ameloblast-derived cells (LS-8), mouse odontogenic epithelia, were exposed to 1 or 5ppm sodium fluoride (NaF) (0.46 and 2.25ppm F, respectively) for 1, 3 and 7 days. The effect of NaF on the mRNA expression of enamel proteins was quantified; the secretion of cytokines, and interleukins, and the alkaline phosphatase (ALP) activity, into the cell culture medium was measured and compared to untreated controls. The effect on cell growth after 1- and 3-days in culture was measured using BrdU incorporation.
  
  
  RESULTS
  Fluoride at 2.25ppm reduced mRNA expression of the structural enamel matrix proteins amelogenin (amel), ameloblastin (ambn), enamelin (enam), and the enamel protease matrix metallopeptidase-20 (MMP-20). Similarly several vascularisation factors (vascular endothelial growth factor (VEGF), monocyte chemoattractant proteins (MCP-1) and interferon inducible protein 10 (IP-10), was also reduced by 2.25ppm fluoride. ALP activity and proliferation were stimulated by 0.46ppm fluoride but inhibited by 2.25ppm fluoride.
  
  
  CONCLUSIONS
  These results indicate that fluoride may impact on the expression of structural enamel proteins and the protease responsible for processing these proteins during the secretory stage of amelogenesis and go some way to explaining the mineralization defect that characterises fluorotic enamel.
authors.affiliation: Department of Biomaterials, Faculty of Dentistry, University of Oslo, Norway.
authors.forename: Elisabeth Aurstad
authors.initials: EA
authors.lastname: Riksen
authors.forename: Anne
authors.initials: A
authors.lastname: Kalvik
authors.forename: Steven
authors.initials: S
authors.lastname: Brookes
authors.forename: Astrid
authors.initials: A
authors.lastname: Hynne
authors.forename: Malcolm L
authors.initials: ML
authors.lastname: Snead
authors.forename: S Petter
authors.initials: SP
authors.lastname: Lyngstadaas
authors.forename: Janne E
authors.initials: JE
authors.lastname: Reseland
mesh_terms: D000469:Alkaline Phosphatase / Q000187:drug effects / Q000378:metabolism; D000565:Ameloblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002327:Cariostatic Agents / Q000494:pharmacology*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects*; D016207:Cytokines / Q000187:drug effects / Q000378:metabolism; D003746:Dental Enamel Proteins / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D007378:Interleukins / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D012969:Sodium Fluoride / Q000494:pharmacology*
chemical_list: D002327:Cariostatic Agents; D016207:Cytokines; D003746:Dental Enamel Proteins; D007378:Interleukins; D012969:Sodium Fluoride; D007770:L-Lactate Dehydrogenase; D000469:Alkaline Phosphatase; D002118:Calcium