PMID- 22580758
OWN - NLM
STAT- MEDLINE
DCOM- 20121016
LR  - 20211203
IS  - 1791-3004 (Electronic)
IS  - 1791-2997 (Linking)
VI  - 6
IP  - 2
DP  - 2012 Aug
TI  - Differential effects of mechanical strain on osteoclastogenesis and 
      osteoclast-related gene expression in RAW264.7 cells.
PG  - 409-15
LID - 10.3892/mmr.2012.908 [doi]
AB  - Mechanical strain plays a critical role in the formation, proliferation and 
      maturation of bone cells. However, little is known about the direct effects of 
      different magnitudes of mechanical strain on osteoclast differentiation. The aim 
      of the present study was to investigate how the fusion and activation of 
      osteoclasts can be regulated by mechanical strain magnitude using the RAW264.7 
      mouse monocyte/macrophage cell line as an osteoclast precursor. Mechanical strain 
      (substrate stretching) was applied via a 4-point bending system when RAW cells 
      were treated with macrophage colony-stimulating factor (M-CSF) and receptor 
      activator of nuclear factor-kappaB (RANK) ligand (RANKL) for an indicated period of 
      time. The numbers of tartrate-resistant acid phosphatase-positive (TRAP+) and 
      apoptotic cells were counted. The expression of TRAP, matrix metalloproteinase-9 
      (MMP-9), RANK, cathepsin K and carbonic anhydrase II (CAII) was measured by 
      semi-quantitative RT-PCR, and immunocytochemistry staining for RANK was 
      performed. We found that the number of nuclei per osteoclast derived from RAW 
      cells decreased under low magnitude mechanical strain and increased under high 
      magnitude strain within physiological load with an enhanced fusion of TRAP+ 
      osteoclasts, compared to the control with no mechanical strain. The expression of 
      RANK mRNA was downregulated by low magnitude strain and beyond physiological 
      load, while it was upregulated by high magnitude strain within physiological 
      load, correlating with the increased expression of RANK examined by 
      immunocytochemistry, suggesting the mechanical regulation of RANK expression. 
      There was also an increase in the expression of MMP-9 mRNA in the groups 
      subjected to a mechanical strain of 2,000 and 2,500 microepsilon. No significant 
      differences were detected in the expression of TRAP mRNA, cathepsin K and CAII 
      under mechanical strain compared to the control under no strain (0 microepsilon). These 
      findings indicate that low-magnitude strain suppresses osteoclast fusion and 
      activation, while high-magnitude strain within physiological load promotes 
      osteoclast fusion and activation related to a mechanical magnitude-dependent 
      response of RANK expression. These data, therefore, provide a deeper 
      understanding of how different magnitudes of mechanical strains exert their 
      effects on osteoclastogenesis.
FAU - Xu, Xiao-Ying
AU  - Xu XY
AD  - Institute of Medical Equipment, Academy of Military Medical Sciences, Tianjin 
      300161, PR China.
FAU - Guo, Chun
AU  - Guo C
FAU - Yan, Yu-Xian
AU  - Yan YX
FAU - Guo, Yong
AU  - Guo Y
FAU - Li, Rui-Xin
AU  - Li RX
FAU - Song, Mei
AU  - Song M
FAU - Zhang, Xi-Zheng
AU  - Zhang XZ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20120508
PL  - Greece
TA  - Mol Med Rep
JT  - Molecular medicine reports
JID - 101475259
RN  - 0 (Isoenzymes)
RN  - 0 (RNA, Messenger)
RN  - 0 (Receptor Activator of Nuclear Factor-kappa B)
RN  - 0 (Tnfrsf11a protein, mouse)
RN  - EC 3.1.3.2 (Acid Phosphatase)
RN  - EC 3.1.3.2 (Acp5 protein, mouse)
RN  - EC 3.1.3.2 (Tartrate-Resistant Acid Phosphatase)
RN  - EC 3.4.22.38 (Cathepsin K)
RN  - EC 3.4.22.38 (Ctsk protein, mouse)
RN  - EC 3.4.24.35 (Matrix Metalloproteinase 9)
RN  - EC 3.4.24.35 (Mmp9 protein, mouse)
RN  - EC 4.2.1.- (Carbonic Anhydrase II)
SB  - IM
MH  - Acid Phosphatase/genetics/metabolism
MH  - Animals
MH  - Apoptosis
MH  - Biomechanical Phenomena
MH  - Carbonic Anhydrase II/genetics/metabolism
MH  - Cathepsin K/genetics/metabolism
MH  - Cell Count
MH  - Cell Culture Techniques
MH  - *Cell Differentiation
MH  - Cell Line
MH  - *Gene Expression Regulation
MH  - Immunochemistry
MH  - Isoenzymes/genetics/metabolism
MH  - Macrophage Activation
MH  - Matrix Metalloproteinase 9/genetics/metabolism
MH  - Mice
MH  - Osteoclasts/*cytology/metabolism/physiology
MH  - RNA, Messenger/genetics/metabolism
MH  - Receptor Activator of Nuclear Factor-kappa B/genetics/metabolism
MH  - Reverse Transcriptase Polymerase Chain Reaction/methods
MH  - *Stress, Mechanical
MH  - Tartrate-Resistant Acid Phosphatase
MH  - Time Factors
OTO - NOTNLM
OT  - osteoclast
OT  - mechanical strain magnitude
OT  - differentiation
OT  - receptor activator of nuclear factor-kappaB expression
EDAT- 2012/05/15 06:00
MHDA- 2012/10/17 06:00
CRDT- 2012/05/15 06:00
PHST- 2012/01/26 00:00 [received]
PHST- 2012/04/27 00:00 [accepted]
PHST- 2012/05/15 06:00 [entrez]
PHST- 2012/05/15 06:00 [pubmed]
PHST- 2012/10/17 06:00 [medline]
AID - 10.3892/mmr.2012.908 [doi]
PST - ppublish
SO  - Mol Med Rep. 2012 Aug;6(2):409-15. doi: 10.3892/mmr.2012.908. Epub 2012 May 8.