Biological responses of osteocytic connexin 43 hemichannels to simulated microgravity

Huiyun Xu, Ruofei Liu, Dandan Ning, Jian Zhang, Ruixin Yang, Manuel A. Riquelme, Jingbao Li, Jean X Jiang, Peng Shang

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Connexin 43 (Cx43) hemichannels and gap junctions in osteocytes are responsive to mechanical loading, which is important for bone formation and remodeling. However, the mechanism of these Cx43-forming channels in the process of mechanical unloading is still not very clear. In this study, unloading caused by weightlessness was simulated by using a random position machine (RPM). Osteocytic MLO-Y4 cells were subjected to 2 h of RPM treatment, and levels of Cx43 mRNA and total and cell surface expressed protein were determined by quantitative real-time PCR, western blotting, and biotinylation analysis. Although mRNA was elevated by RPM, total protein level of Cx43 was not altered; however, surface biotinylated Cx43 was significantly reduced. Interestingly, RPM promoted the retention of Cx43 in the Golgi apparatus detected by co-immunofluorescence with antibodies against Cx43 and 58 K Golgi marker protein. Dye uptake assay showed that hemichannels were induced open after RPM for 2 h. Consistently, prostaglandin E2 release was increased and this increase was completely attenuated with the treatment of a Cx43 hemichannel blocking antibody. Together, this study demonstrates increased activity of Cx43 hemichannels to RPM, and active Cx43 hemichannels with prostaglandin E2 release are likely to module biological function under simulated weightless conditions.

Original languageEnglish (US)
Pages (from-to)1195-1202
Number of pages8
JournalJournal of Orthopaedic Research
Volume35
Issue number6
DOIs
StatePublished - Jun 1 2017

Fingerprint

Weightlessness
Connexin 43
Dinoprostone
Mechanical Phenomena
Biotinylation
Osteocytes
Messenger RNA
Blocking Antibodies
Bone Remodeling
Gap Junctions
Golgi Apparatus
Osteogenesis
Fluorescent Antibody Technique
Real-Time Polymerase Chain Reaction
Membrane Proteins
Proteins
Coloring Agents
Western Blotting

Keywords

  • connexin43
  • hemichannel
  • osteocyte
  • random position machine

ASJC Scopus subject areas

  • Orthopedics and Sports Medicine

Cite this

Xu, H., Liu, R., Ning, D., Zhang, J., Yang, R., Riquelme, M. A., ... Shang, P. (2017). Biological responses of osteocytic connexin 43 hemichannels to simulated microgravity. Journal of Orthopaedic Research, 35(6), 1195-1202. https://doi.org/10.1002/jor.23224

Biological responses of osteocytic connexin 43 hemichannels to simulated microgravity. / Xu, Huiyun; Liu, Ruofei; Ning, Dandan; Zhang, Jian; Yang, Ruixin; Riquelme, Manuel A.; Li, Jingbao; Jiang, Jean X; Shang, Peng.

In: Journal of Orthopaedic Research, Vol. 35, No. 6, 01.06.2017, p. 1195-1202.

Research output: Contribution to journalArticle

Xu, H, Liu, R, Ning, D, Zhang, J, Yang, R, Riquelme, MA, Li, J, Jiang, JX & Shang, P 2017, 'Biological responses of osteocytic connexin 43 hemichannels to simulated microgravity', Journal of Orthopaedic Research, vol. 35, no. 6, pp. 1195-1202. https://doi.org/10.1002/jor.23224
Xu, Huiyun ; Liu, Ruofei ; Ning, Dandan ; Zhang, Jian ; Yang, Ruixin ; Riquelme, Manuel A. ; Li, Jingbao ; Jiang, Jean X ; Shang, Peng. / Biological responses of osteocytic connexin 43 hemichannels to simulated microgravity. In: Journal of Orthopaedic Research. 2017 ; Vol. 35, No. 6. pp. 1195-1202.
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