title: [Effect of lipopolysaccharides from Porphyromonas endodontalis on the expression of macrophage colony stimulating factor in mouse osteoblasts].
abstract: OBJECTIVE
  To investigate the effects of lipopolysaccharides (LPS) extracted from Porphyromonas endodontalis (Pe) on the expression of macrophage colony stimulating factor (M-CSF) mRNA and protein in MC3T3-E1 cells and the role of nucler factor-κB (NF-κB) in the process.
  
  
  METHODS
  MC3T3-E1 cells were treated with different concentrations of Pe-LPS (0-50 mg/L) and 10 mg/L Pe-LPS for different hours (0-24 h). The expression of M-CSF mRNA and protein was detected by reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunoadsordent assay (ELISA). The cells untreated by Pe-LPS served as control. The expression of M- CSF mRNA and protein was also detected in 10 mg/L Pe- LPS treated MC3T3-E1 cells after pretreated with BAY 11-7082 for 1 h, a special NF-κB inhibitor. The groups were divided as follows, control group, BAY group (10 µmol/L BAY 11-7082 treated alone MC3T3-E1 cells), Pe-LPS group (10 mg/L Pe-LPS stimulated MC3T3-E1 cells for 6 h), BAY combine with Pe-LPS group (10 µmol/L BAY 11-7082 pretreated cells for 1 h and 10 mg/L of Pe-LPS stimulated MC3T3-E1 cells for 6 h).
  
  
  RESULTS
  The level of M- CSF mRNA and protein increased significantly after treatment with different concentrations of Pe-LPS (0-50 mg/L), which indicated that Pe-LPS induced osteoblasts to express M-CSF mRNA and protein in dose dependent manners. The expression of M-CSF protein increased from (35 ± 2) ng/L (control group) to (170 ± 8) ng/L (50 mg/L group). Maximal induction of M-CSF mRNA expression was found in the MC3T3- E1 cells treated with 10 mg/L Pe-LPS for 6 h. After 6 h, the expression of M-CSF mRNA decreased gradually. The expression of M-CSF protein also increased with the treatment of 10 mg/L Pe-LPS for 10 h [(122 ± 4) ng/L]. After 10 h, the expression of M-CSF protein decreased gradually. The mRNA and proteins of M-CSF decreased significantly after pretreatment with 10 µmol/L BAY 11-7082 for 1 h. There was no significant difference between BAY group and the control.
  
  
  CONCLUSIONS
  Pe-LPS may induce the expression of M-CSF mRNA and protein in MC3T3-E1 cells through the signaling of NF-κB.
authors.affiliation: Department of Endodontics, School of Stomatology, China Medical University & Liaoning Institute of Dental Research, Shenyang 110002, China.
authors.forename: Yaqiong
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Email: drqlh@yahoo.com.
authors.forename: Lihong
authors.initials: L
authors.lastname: Qiu
authors.forename: Jiajie
authors.initials: J
authors.lastname: Guo
authors.forename: Liu
authors.initials: L
authors.lastname: Qu
authors.forename: Liya
authors.initials: L
authors.lastname: Xu
authors.forename: Ming
authors.initials: M
authors.lastname: Zhong
mesh_terms: D000818:Animals; D008070:Lipopolysaccharides / Q000494:pharmacology*; D016173:Macrophage Colony-Stimulating Factor / Q000187:drug effects* / Q000502:physiology; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism; D009570:Nitriles; D010006:Osteoblasts / Q000187:drug effects / Q000378:metabolism*; D045202:Porphyromonas endodontalis; D012333:RNA, Messenger; D015398:Signal Transduction; D013450:Sulfones
chemical_list: C434003:3-(4-methylphenylsulfonyl)-2-propenenitrile; D008070:Lipopolysaccharides; D016328:NF-kappa B; D009570:Nitriles; D012333:RNA, Messenger; D013450:Sulfones; D016173:Macrophage Colony-Stimulating Factor