title: Effect of compressive force on human osteoblast-like cells and bone remodelling: an in vitro study.
abstract: OBJECTIVE
  The aim of this study was to determine the effect of continuous compressive force (CF) on expression by human alveolar bone-derived osteoblasts (HOBs) of some specific molecules involved in bone remodelling.
  
  
  METHODS
  HOBs were cultured with or without CF (control, 2.0, 4.0gcm(-2)) for 1, 3 and 7 days. Expression of alkaline phosphatase (ALP), type I collagen (Col I), osteopontin (OPN), osteocalcin (OCN), transcription factor Runx2, receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG) and prostaglandin E2 (PGE2) was analysed by real-time-polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and/or immunostaining.
  
  
  RESULTS
  The results revealed that CF upregulated ALP and Col I expression at both messenger RNA (mRNA) and protein levels but did not affect expression of OPN and OCN mRNA. Runx2 mRNA was inhibited by CF, which also altered the expression of molecules involved in osteoclastogenesis, by enhancing RANKL expression and suppressing OPG expression. At 4.0gcm(-2) of CF, the expression of RANKL and PGE2 was significantly upregulated.
  
  
  CONCLUSIONS
  The results suggest that initial application of CF on HOBs can simultaneously affect expression of markers related to both osteogenesis and osteoclastogenesis.
authors.affiliation: Department of Clinical Dentistry - Centre for Clinical Dental Research, Faculty of Medicine and Dentistry, University of Bergen, PO Box 7804, N-5020 Bergen, Norway. Polbhat.Tripuwabhrut@iko.uib.no
authors.forename: Polbhat
authors.initials: P
authors.lastname: Tripuwabhrut
authors.forename: Manal
authors.initials: M
authors.lastname: Mustafa
authors.forename: Cecilie G
authors.initials: CG
authors.lastname: Gjerde
authors.forename: Pongsri
authors.initials: P
authors.lastname: Brudvik
authors.forename: Kamal
authors.initials: K
authors.lastname: Mustafa
mesh_terms: D000293:Adolescent; D000328:Adult; D000469:Alkaline Phosphatase / Q000032:analysis*; D000539:Alveolar Process / Q000378:metabolism*; D000704:Analysis of Variance; D016723:Bone Remodeling / Q000235:genetics / Q000502:physiology*; D002478:Cells, Cultured; D003094:Collagen / Q000032:analysis*; D050659:Core Binding Factor Alpha 1 Subunit / Q000032:analysis; D015232:Dinoprostone / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D006801:Humans; D010006:Osteoblasts / Q000378:metabolism*; D015675:Osteocalcin / Q000032:analysis; D053495:Osteopontin / Q000032:analysis; D053244:Osteoprotegerin / Q000032:analysis; D053245:RANK Ligand / Q000032:analysis; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D013314:Stress, Mechanical; D014087:Tooth Movement Techniques
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; C493709:RUNX2 protein, human; C505688:TNFSF11 protein, human; D015675:Osteocalcin; D053495:Osteopontin; D003094:Collagen; D000469:Alkaline Phosphatase; D015232:Dinoprostone