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Apoptotic Osteocytes and the Control of Targeted Bone Resorption

  • Skeletal Biology and Regulation (MR Forwood and A Robling, Section Editors)
  • Published:
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Abstract

Studies from the 1950s and 1960s already recognize the fact that osteocytes, although long living cells, die, as evidenced by accumulation of osteocytic lacunae devoid of cells. More recently, it was demonstrated that these cells die by apoptosis. The rate of osteocyte apoptosis is regulated by the age of the bone, as well as by systemic hormones, local growth factors, cytokines, pharmacological agents, and mechanical forces. Apoptotic osteocytes, in turn, recruit osteoclasts to initiate targeted bone resorption. This results in the removal of “dead” bone and may improve the mechanical properties of the skeleton. However, the molecular regulators of osteocyte survival and targeted bone remodeling are not completely known. In this review, the current knowledge on the molecular mechanism that lead to osteocyte death or survival, and the signals that mediate targeted bone resorption is discussed.

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Acknowledgement

This research was supported by National Institutes of Health (R01-AR053643) and by a Biomedical Research Grant and a Developing Diverse Researchers with InVestigative Expertise (DRIVE) Grant from Indiana University School of Medicine.

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Conflict of Interest

L.I. Plotkin declares that she has no conflicts of interest.

Human and Animal Rights and Informed Consent

All studies by L. I. Plotkin involving murine samples were performed after approval by the Institutional Animal Care and Use Committees of University of Arkansas for Medical Sciences and Indiana University School of Medicine.

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  1. Department of Anatomy and Cell Biology, Indiana University School of Medicine, 635 Barnhill Drive, MS-5035, Indianapolis, IN, USA

    Lilian I. Plotkin

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Correspondence to Lilian I. Plotkin.

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Plotkin, L.I. Apoptotic Osteocytes and the Control of Targeted Bone Resorption. Curr Osteoporos Rep 12, 121–126 (2014). https://doi.org/10.1007/s11914-014-0194-3

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  • DOI: https://doi.org/10.1007/s11914-014-0194-3

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