Mechanical strain-induced proliferation of osteoblastic cells parallels increased TGF-beta 1 mRNA.
It is well known that mechanical stimulation can prompt healing of bone fractures. However, the mechanism involved is less clear. In this study, we found that a 0.17% cyclic, biaxial mechanical strain delivered at 1 Hz increased proliferation of MC3T3-E1 cells, a clonal osteoblastic cell line. Mechanical strain also increased the level of TGF-beta 1 mRNA determined by quantitative reverse transcription/ polymerase chain reaction. Previous reports have shown that neomycin and W-7, which are inhibitors in the inositol phosphate/calmodulin pathway, blocked mechanical strain-induced proliferation of the osteoblast cells. Interestingly, we found that neomycin and W-7 can also block mechanical stimulation-induced elevation of TGF-beta 1 mRNA. Finally, using an antibody which blocked the action of TGF-beta 1, we found that the increased MC3T3-E1 cell proliferation induced by mechanical strain did not depend on the action of TGF-beta 1.
Zhuang
H
H
Department of Orthopaedic Surgery, University of Pennsylvania School of Medicine, Philadelphia 19082-6081, USA.
Wang
W
W
Tahernia
A D
AD
Levitz
C L
CL
Luchetti
W T
WT
Brighton
C T
CT
D016475:3T3 Cells; D000818:Animals; D002147:Calmodulin / Q000378:metabolism; D002455:Cell Division / Q000235:genetics*; D007295:Inositol Phosphates / Q000378:metabolism; D051379:Mice; D010006:Osteoblasts / Q000166:cytology*; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000235:genetics*
D002147:Calmodulin; D007295:Inositol Phosphates; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta