title: Enamel matrix derivative neutralized the effect of lipopolysaccharide on osteoprotegerin and receptor activator of nuclear factor kappa B ligand expression of osteoblasts.
abstract: OBJECTIVE
  In this study, we investigated the effects of enamel matrix derivative (EMD) on osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) expression of osteoblasts in the presence of lipopolysaccharide (LPS).
  
  
  METHODS
  OPG and RANKL gene expression and protein synthesis of MC3T3-E1 osteoblastic cells were examined by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay.
  
  
  RESULTS
  LPS inhibited OPG gene expression and protein synthesis, and stimulated RANKL gene expression and soluble RANKL synthesis. EMD enhanced OPG gene expression and protein synthesis, and inhibited RANKL gene expression and soluble RANKL synthesis. Furthermore, EMD neutralized the effects of LPS on OPG and RANKL expression in osteoblasts.
  
  
  CONCLUSIONS
  EMD might regulate the function of osteoblasts by elevating the ratio of OPG/RANKL gene expression, which is downregulated by LPS, and suppress the induction of osteoclastogenesis. Thereby, EMD might contribute to periodontal tissue regeneration.
authors.affiliation: Department of Oral Health Science, Graduate School of Dentistry, Hokkaido University, Nishi 7, Kita 13, Kita-ku, Sapporo 060-8586, Japan. wada4888@jeans.ocn.ne.jp
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Wada
authors.forename: Morimichi
authors.initials: M
authors.lastname: Mizuno
authors.forename: Masato
authors.initials: M
authors.lastname: Tamura
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003743:Dental Enamel / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D008070:Lipopolysaccharides / Q000378:metabolism*; D008297:Male; D053244:Osteoprotegerin / Q000235:genetics / Q000378:metabolism*; D053245:RANK Ligand / Q000235:genetics / Q000378:metabolism*
chemical_list: D008070:Lipopolysaccharides; D053244:Osteoprotegerin; D053245:RANK Ligand