Calcium response in single osteocytes to locally applied mechanical stimulus: Differences in cell process and cell body

Taiji Adachi, Yuki Aonuma, Mototsugu Tanaka, Masaki Hojo, Teruko Takano-Yamamoto, Hiroshi Kamioka

Research output: Contribution to journalArticle

83 Citations (Scopus)

Abstract

It is proposed that osteocytes embedded in the bone matrix have the ability to sense deformation and/or damage to the matrix and to feed these mechanical signals back to the adaptive bone remodeling process. When osteoblasts differentiate into osteocytes during the bone formation process, they change their morphology to a stellate form with many slender processes. This characteristic cell shape may underlie the differences in mechanosensitivity between the cell processes and cell body. To elucidate the mechanism of cellular response to mechanical stimulus in osteocytes, we investigated the site-dependent response to quantitatively controlled local mechanical stimulus in single osteocytes isolated from chick embryos, using the technique of calcium imaging. A mechanical stimulus was applied to a single osteocyte using a glass microneedle targeting a microparticle adhered to the cell membrane by modification with a monoclonal antibody OB7.3. Application of the local deformation induced calcium transients in the vicinity of the stimulated point and caused diffusive wave propagation of the calcium transient to the entire intracellular region. The rate of cell response to the stimulus was higher when applied to the cell processes than when applied to the cell body. In addition, a large deformation was necessary at the cell body to induce calcium transients, whereas a relatively small deformation was sufficient at the cell processes, suggesting that the mechanosensitivity of the cell processes was higher than that of the cell body. These results suggest that the cell shape with slender processes contributes to the site-dependent mechanosensitivity in osteocytes.

Original languageEnglish
Pages (from-to)1989-1995
Number of pages7
JournalJournal of Biomechanics
Volume42
Issue number12
DOIs
Publication statusPublished - Aug 25 2009

Keywords

  • Bone cells
  • Calcium signaling response
  • Cell biomechanics
  • Mechanical stimulus
  • Mechanotransduction
  • Osteocytes

ASJC Scopus subject areas

  • Biophysics
  • Orthopedics and Sports Medicine
  • Biomedical Engineering
  • Rehabilitation

Fingerprint Dive into the research topics of 'Calcium response in single osteocytes to locally applied mechanical stimulus: Differences in cell process and cell body'. Together they form a unique fingerprint.

  • Cite this