PMID- 12568966
OWN - NLM
STAT- MEDLINE
DCOM- 20030318
LR  - 20131121
IS  - 0736-0266 (Print)
IS  - 0736-0266 (Linking)
VI  - 21
IP  - 2
DP  - 2003 Mar
TI  - Pulsed electromagnetic fields affect phenotype and connexin 43 protein expression 
      in MLO-Y4 osteocyte-like cells and ROS 17/2.8 osteoblast-like cells.
PG  - 326-34
AB  - Osteocytes, the predominant cells in bone, are postulated to be responsible for 
      sensing mechanical and electrical stimuli, transducing signals via gap junctions. 
      Osteocytes respond to induced shear by increasing connexin 43 (Cx43) levels, 
      suggesting that they might be sensitive to physical stimuli like low-frequency 
      electromagnetic fields (EMF). Immature osteoblasts exhibit decreased 
      intercellular communication in response to EMF but no change in Cx43. Here, we 
      examined long term effects of pulsed EMF (PEMF) on MLO-Y4 osteocyte-like cells 
      and ROS 17/2.8 osteoblast-like cells. In MLO-Y4 cell cultures, PEMF for 8 h/day 
      for one, two or four days increased alkaline phosphatase activity but had no 
      effect on cell number or osteocalcin. Transforming growth factor beta-1 (TGF-beta 
      1) and prostaglandin E(2) were increased, and NO(2-) was altered. PEMFs effect on 
      TGF-beta1 was via a prostaglandin-dependent mechanism involving Cox-1 but not 
      Cox-2. In ROS 17/2.8 cells, PEMF for 24, 48 or 72 h did not affect cell number, 
      osteocalcin mRNA or osteocalcin protein. PEMF reduced Cx43 protein in both cells. 
      Longer exposures decreased Cx43 mRNA. This indicates that cells in the osteoblast 
      lineage, including well-differentiated osteoblast-like ROS 17/2.8 cells and 
      terminally differentiated osteocyte-like MLO-Y4 cells, respond to PEMF with 
      changes in local factor production and reduced Cx43, suggesting decreased gap 
      junctional signaling.
FAU - Lohmann, C H
AU  - Lohmann CH
AD  - Department of Orthopaedics, The University of Texas Health Science Center at San 
      Antonio, San Antonio, TX 78229, USA.
FAU - Schwartz, Z
AU  - Schwartz Z
FAU - Liu, Y
AU  - Liu Y
FAU - Li, Z
AU  - Li Z
FAU - Simon, B J
AU  - Simon BJ
FAU - Sylvia, V L
AU  - Sylvia VL
FAU - Dean, D D
AU  - Dean DD
FAU - Bonewald, L F
AU  - Bonewald LF
FAU - Donahue, H J
AU  - Donahue HJ
FAU - Boyan, B D
AU  - Boyan BD
LA  - eng
GR  - AG-13087/AG/NIA NIH HHS/United States
GR  - AR-46798/AR/NIAMS NIH HHS/United States
GR  - DE-05937/DE/NIDCR NIH HHS/United States
GR  - DE-08603/DE/NIDCR NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Orthop Res
JT  - Journal of orthopaedic research : official publication of the Orthopaedic 
      Research Society
JID - 8404726
RN  - 0 (Connexin 43)
RN  - 0 (Enzyme Inhibitors)
RN  - 0 (Isoenzymes)
RN  - 0 (Membrane Proteins)
RN  - 0 (Nitrites)
RN  - 0 (RNA, Messenger)
RN  - 0 (Tgfb1 protein, mouse)
RN  - 0 (Transforming Growth Factor beta)
RN  - 0 (Transforming Growth Factor beta1)
RN  - EC 1.14.99.1 (Cyclooxygenase 1)
RN  - EC 1.14.99.1 (Prostaglandin-Endoperoxide Synthases)
RN  - EC 1.14.99.1 (Ptgs1 protein, mouse)
RN  - EC 3.1.3.1 (Alkaline Phosphatase)
RN  - K7Q1JQR04M (Dinoprostone)
SB  - IM
MH  - Alkaline Phosphatase/metabolism
MH  - Animals
MH  - Connexin 43/genetics/*metabolism
MH  - Cyclooxygenase 1
MH  - Dinoprostone/metabolism
MH  - Dose-Response Relationship, Drug
MH  - *Electric Stimulation Therapy
MH  - *Electromagnetic Fields
MH  - Enzyme Inhibitors/pharmacology
MH  - Isoenzymes/antagonists & inhibitors/metabolism
MH  - Membrane Proteins
MH  - Mice
MH  - Mice, Transgenic
MH  - Nitrites/metabolism
MH  - Osteoblasts/metabolism/pathology/*radiation effects
MH  - Osteocytes/metabolism/pathology/*radiation effects
MH  - Phenotype
MH  - Prostaglandin-Endoperoxide Synthases/metabolism
MH  - RNA, Messenger/metabolism
MH  - Transforming Growth Factor beta/metabolism
MH  - Transforming Growth Factor beta1
MH  - Tumor Cells, Cultured
EDAT- 2003/02/06 04:00
MHDA- 2003/03/19 04:00
CRDT- 2003/02/06 04:00
PHST- 2003/02/06 04:00 [pubmed]
PHST- 2003/03/19 04:00 [medline]
PHST- 2003/02/06 04:00 [entrez]
AID - S0736026602001377 [pii]
AID - 10.1016/S0736-0266(02)00137-7 [doi]
PST - ppublish
SO  - J Orthop Res. 2003 Mar;21(2):326-34. doi: 10.1016/S0736-0266(02)00137-7.