title: Low concentrations of TNF-α promote osteogenic differentiation via activation of the ephrinB2-EphB4 signalling pathway.
abstract: OBJECTIVE
  Low concentrations of tumour necrosis factor-alpha (TNF-α) have been reported to promote osteogenic differentiation. In this study, a series of in vitro experiments was performed to investigate underlying molecular mechanisms involved.
  
  
  METHODS
  MC3T3-E1 murine preosteoblasts were treated with TNF-α at doses of 0, 0.1 or 1 ng/mL. The ephrinB2-EphB4 signalling pathway was activated using ephrinB2-fc, or inhibited using lentiviruses encoding siRNAs specifically targeting EphB4. Cell proliferation/survival was evaluated using the Cell Counting Kit-8 (CCK-8) assay, and expression levels of Runx2, BSP, ephrinB2 and EphB4 were determined using RT-PCR and Western blotting. ALP activity in these cells was also determined, and mineral nodule formation was evaluated with alizarin red S staining.
  
  
  RESULTS
  Low concentrations of TNF-α had no influence on cell proliferation/survival. However, expression levels of Runx2, BSP, ephrinB2 and EphB4, as well as ALP activity and mineral nodule formation, were significantly enhanced in MC3T3-E1 cells treated with low concentrations of TNF-α. Moreover, activation of the ephrinB2-EphB4 signalling pathway by ephrinB2-fc enhanced TNF-α-induced osteogenic differentiation, while down-regulation of EphB4 level reversed the positive effect of TNF-α.
  
  
  CONCLUSIONS
  Low concentrations of TNF-α promoted osteogenic differentiation via activation of the ephrinB2-EphB4 signalling pathway.
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, Jinan, Shandong, China.|Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Jinan, Shandong, China.
authors.forename: Limei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Endodontics, School of Stomatology, Shandong University, Jinan, Shandong, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Prosthodontics, School of Stomatology, Shandong University, Jinan, Shandong, China.
authors.forename: Cunwei
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Stomatology, Qilu Hospital, and Institute of Stomatology, Shandong University, Jinan, Shandong, China.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Qi
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, Jinan, Shandong, China.
authors.forename: Mi
authors.initials: M
authors.lastname: Du
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, Jinan, Shandong, China.
authors.forename: Wenhua
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Oral & Maxillofacial Surgery, Qilu Hospital, and Institute of Stomatology, Shandong University, Jinan, Shandong, China.
authors.forename: Chengzhe
authors.initials: C
authors.lastname: Yang
authors.affiliation: Department of Periodontology, School of Stomatology, Shandong University, Jinan, Shandong, China.|Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Jinan, Shandong, China.
authors.forename: Pishan
authors.initials: P
authors.lastname: Yang
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000378:metabolism; D036388:Ephrin-B2 / Q000235:genetics / Q000378:metabolism*; D058574:Integrin-Binding Sialoprotein / Q000235:genetics / Q000378:metabolism; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects*; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D036224:Receptor, EphB4 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; D036388:Ephrin-B2; C546872:Ibsp protein, mouse; D058574:Integrin-Binding Sialoprotein; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014409:Tumor Necrosis Factor-alpha; C086681:Ephb4 protein, mouse; D036224:Receptor, EphB4; D000469:Alkaline Phosphatase