title: [The effect of Smads signal pathway on the osteogenesis of human periodontal ligament stem cells in simulated microgravity].
abstract: PUPOSE: To investigate the effect of Smads signal pathway on the osteogenesis of human periodontal ligament stem cells (hPDLSCs) in simulated microgravity.
  
  
  METHODS
  Human periodontal ligament stem cells were isolated from the ligament of surgically extracted human teeth.Through limiting dilution assay, mono-clone of the cell was obtained, hPDLSCs were isolated from MesenPRO RS medium. Rotary cell culture system (RCCS) was enrolled to set simulated microgravity (SMG). Samples were set to control group (normal gravity group, NG) and simulated microgravity group (SMG). Real-time PCR was used to detect the expression of Smads signals and the expression of markers of osteogenesis before and after SIS3. The amount of phosphated-Smad was assayed by flow cytometry. Statistical analysis of the data was done by ANOVA with SPSS 13.0 software package.
  
  
  RESULTS
  Compared with that of the control group, the expression of Smads 2,3,4 was significantly higher in SMG group (P<0.05)in a time-dependent manner. Flow cytometry assay showed increased expression of p-Smads at 30-min, and peak expression was observed at 2h,reaching at 91.32%. The addition of SIS3 led to significant decrease of COL I, ALP, OCN and p-Smads (P<0.05).
  
  
  CONCLUSIONS
  Smads signal pathway was enrolled in the osteogenesis of hPDLSCs in simulated microgravity.
authors.affiliation: Oral Disease Treatment Center of PLA, 306 Hospital, Beijing 100101, China. lilypurity@sina.com
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Shi
authors.initials: S
authors.lastname: Li
authors.forename: Zhong-ying
authors.initials: ZY
authors.lastname: Niu
authors.forename: Bo
authors.initials: B
authors.lastname: Bao
authors.forename: Xin
authors.initials: X
authors.lastname: Shi
mesh_terms: D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D010012:Osteogenesis; D010513:Periodontal Ligament; D015398:Signal Transduction; D013234:Stem Cells; D014893:Weightlessness