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Current Osteoporosis Reports

, Volume 1, Issue 1, pp 5–10 | Cite as

Osteocyte and bone structure

  • Jenneke Klein-Nulend
  • Peter J. Nijweide
  • Elisabeth H. Burger
Article

Abstract

The osteocyte is the most abundant cell type of bone. There are approximately 10 times as many osteocytes as osteoblasts in adult human bone, and the number of osteoclasts is only a fraction of the number of osteoblasts. Our current knowledge of the role of osteocytes in bone metabolism is far behind our insight into the properties and functions of the osteoblasts and osteoclasts. However, the striking structural design of bone predicts an important role for osteocytes in determining bone structure. Over the past several years, the role of osteocytes as the professional mechanosensory cells of bone, and the lacunocanalicular porosity as the structure that mediates mechanosensing have become clear. Strain-derived flow of interstitial fluid through this porosity seems to mechanically activate the osteocytes, as well as ensure transport of cell signaling molecules, nutrients, and waste products. This concept explains local bone gain and loss—as well as remodeling in response to fatigue damage—as processes supervised by mechanosensitive osteocytes. Alignment during remodeling seems to occur as a result of the osteocyte’s sensing different canalicular flow patterns around the cutting cone and reversal zone during loading, therefore determining the bone’s structure.

Keywords

Nitric Oxide Fluid Shear Stress Human Bone Cell Reversal Zone Basic Multicellular Unit 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Current Science Inc 2003

Authors and Affiliations

  • Jenneke Klein-Nulend
    • 1
  • Peter J. Nijweide
  • Elisabeth H. Burger
  1. 1.Department of Oral Cell BiologyACTA-Vrije UniversiteitBT AmsterdamThe Netherlands

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