Bone research, 2013-12, Vol.1 (4), p.355-361
2013
Details
- Autor(en) / Beteiligte
- Titel
- Elevated Intracellular Ca2＋ Signals by Oxidative Stress Activate Connexin 43 Hemichannels in Osteocytes
- Ist Teil von
- Bone research, 2013-12, Vol.1 (4), p.355-361
- Ort / Verlag
- London: Springer Nature B.V
- Erscheinungsjahr
- 2013
- Link zum Volltext
- Quelle
- Electronic Journals Library
- Beschreibungen/Notizen
- Elevated oxidative stress （OS） during aging leads to bone loss. OS increases intracellular Ca2＋ （[Ca2＋]i）, resulting in cellular damage and death. We show earlier that Cx43 hemichannels open in response to OS, which serves as a protective mechanism for osteocytes. However, the underlying mechanism is unknown. Here, we found that treatment with H202 increased [Ca2＋]i in osteocytes with [Ca2＋]i being primarily derived from an extracellular Ca2~ source. Hemichannel opening induced by OS was inhibited by the depletion of [Ca2＋]i with BAPTA-AM, a Ca2＋ chelator, suggesting that [Ca2＋]i influenced the activity of Cx43 hemichannels. Conversely, blockade of hemichannels had no effect on [Ca2＋]i. A biotinylation assay showed that cell surface-expressed Cx43 was increased by OS, which could be inhibited by BAPTA-AM, suggesting that [Ca2＋]i is necessary for Cx43 migration to the cell surface in response to OS. Together, these data suggest that increased hemichannel activity induced by OS was likely to be caused by elevated [Ca2＋]i through increased Cx43 on the cell surface.