title: Oral bacterial extracts facilitate early osteogenic/dentinogenic differentiation in human dental pulp-derived cells.
abstract: OBJECTIVE
  Bacterial metabolites demineralize dental hard tissues, and soluble factors lead to tertiary dentinogenesis in the area of the dentin-pulp complex. However, it is unclear whether the oral bacteria are directly involved in the differentiation of dental pulp cells. In this study, we evaluated the effect of oral bacterial extracts on cellular differentiation in human dental pulp-derived cells (hDPC).
  
  
  METHODS
  The hDPC were obtained from third molar teeth, and the cells were subcultured. The sonicated extracts were obtained from Porphyromonas gingivalis (gram-negative) and Streptococcus mutans (gram-positive). The effect of bacterial extracts on cellular growth and differentiation in hDPC were tested.
  
  
  RESULTS
  Alkaline phosphatase activity and bone sialoprotein (BSP) gene expression were increased in hDPC exposed to low concentrations of both sonicated extracts, whereas the activity was decreased upon exposure to high concentrations of sonicated extracts from P. gingivalis.
  
  
  CONCLUSIONS
  This is the first evidence that oral bacteria have a positive effect on cellular differentiation in hPDC.
authors.affiliation: Division of Stem Sell Engineering, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Shu
authors.initials: S
authors.lastname: Abe
authors.forename: Mari
authors.initials: M
authors.lastname: Imaizumi
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Mikami
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Wada
authors.forename: Shuhei
authors.initials: S
authors.lastname: Tsuchiya
authors.forename: Seiko
authors.initials: S
authors.lastname: Irie
authors.forename: Shinnosuke
authors.initials: S
authors.lastname: Suzuki
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Satomura
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Ishihara
authors.forename: Masaki J
authors.initials: MJ
authors.lastname: Honda
mesh_terms: D000704:Analysis of Variance; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology*; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D003810:Dentinogenesis / Q000187:drug effects*; D004731:Endotoxins; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D058574:Integrin-Binding Sialoprotein; D010012:Osteogenesis / Q000187:drug effects*; D010750:Phosphoproteins / Q000096:biosynthesis / Q000235:genetics; D016966:Porphyromonas gingivalis; D012795:Sialoglycoproteins / Q000096:biosynthesis / Q000235:genetics; D013010:Sonication; D018709:Statistics, Nonparametric; D013295:Streptococcus mutans; D000099311:Dentin Sialophosphoprotein
chemical_list: D017077:Culture Media, Conditioned; D004731:Endotoxins; D016326:Extracellular Matrix Proteins; D058574:Integrin-Binding Sialoprotein; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C513309:DMP1 protein, human; C546871:IBSP protein, human