title: Effects of enamel matrix proteins on proliferation, differentiation and attachment of human alveolar osteoblasts.
abstract: OBJECTIVE
  Enamel matrix proteins (EMPs) have been demonstrated to promote periodontal regeneration. However, effects of EMPs on human alveolar osteoblasts (hAOBs), up to now, have still been unclear. The purpose of this study was to investigate influence of EMPs on proliferation, differentiation and attachment of hAOBs in vitro.
  
  
  METHODS
  EMPs were extracted using the acetic acid method, hAOBs were obtained and cultured in vitro. Cell proliferation, alkaline phosphatase (ALP) activity, mRNA expression of osteogenic markers and cell attachment were measured in the absence and in the presence of EMPs (50, 100 and 200 μg/ml).
  
  
  RESULTS
  EMPs increased proliferation of hAOBs; however, they inhibited ALP activity and mRNA expression of osteogenic markers (collagen I, ALP, runt-related protein 2, osteocalcin, bone sialoprotein and osteopontin). Meanwhile, EMPs hindered hAOBs' attachment. These effects occurred in EMPs concentration-dependent manner.
  
  
  CONCLUSIONS
  These results indicate that EMPs may inhibit osteoblastic differentiation and attachment to prevent ankylosis and allow other cell types to regenerate periodontal tissues.
authors.affiliation: Department of Periodontology, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, China.
authors.forename: S-Y
authors.initials: SY
authors.lastname: Jiang
authors.forename: R
authors.initials: R
authors.lastname: Shu
authors.forename: Z-C
authors.initials: ZC
authors.lastname: Song
authors.forename: Y-F
authors.initials: YF
authors.lastname: Xie
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors; D000818:Animals; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects*; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D024042:Collagen Type I / Q000037:antagonists & inhibitors; D050659:Core Binding Factor Alpha 1 Subunit / Q000037:antagonists & inhibitors; D003746:Dental Enamel Proteins / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008297:Male; D010006:Osteoblasts / Q000187:drug effects*; D015675:Osteocalcin / Q000037:antagonists & inhibitors; D053495:Osteopontin / Q000037:antagonists & inhibitors; D010518:Periodontitis / Q000378:metabolism; D013552:Swine; D055815:Young Adult
chemical_list: D024042:Collagen Type I; D050659:Core Binding Factor Alpha 1 Subunit; D003746:Dental Enamel Proteins; C493709:RUNX2 protein, human; C109069:enamel matrix proteins; D015675:Osteocalcin; D053495:Osteopontin; D000469:Alkaline Phosphatase