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Current Osteoporosis Reports
Published in: Current Osteoporosis Reports 2/2015

01-04-2015 | Osteocytes (T Bellido and J Klein-Nulend, Section Editors)

Cx43 and Mechanotransduction in Bone

Authors: Lilian I. Plotkin, Toni L. Speacht, Henry J. Donahue

Published in: Current Osteoporosis Reports | Issue 2/2015

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Abstract

Bone adaptation to changes in mechanical stimuli occurs by adjusting bone formation and resorption by osteoblasts and osteoclasts, to maintain optimal bone mass. Osteocytes coordinate the actions of these cells on the bone surface by sensing mechanical forces and producing cytokines that increase or prevent osteoblast and osteoclast differentiation and function. Channels formed by connexins (Cxs) and, in particular, connexin 43 (Cx43) in osteoblasts and osteocytes are central part of this mechanism to control bone mass. Cx43 hemichannels are opened by fluid flow and mediate the anti-apoptotic effect of mechanical stimulation in vitro, suggesting that Cx43 participates in mechanotransduction. However, mice lacking Cx43 in osteoblasts and/or osteocytes show an increased anabolic response to loading and decreased catabolic response to unloading. This evidence suggests that Cx43 channels expressed in osteoblastic cells are not required for the response to mechanical stimulation, but mediate the consequence of lack thereof. The molecular basis of these unexpected responses to mechanical stimulation is currently under investigation.
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Metadata
Title
Cx43 and Mechanotransduction in Bone
Authors
Lilian I. Plotkin
Toni L. Speacht
Henry J. Donahue
Publication date
01-04-2015
Publisher
Springer US
Published in
Current Osteoporosis Reports / Issue 2/2015
Print ISSN: 1544-1873
Electronic ISSN: 1544-2241
DOI
https://doi.org/10.1007/s11914-015-0255-2

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