Influences of mechanical damaged osteocytes induced by over physiological stretching on osteoclastgenesis in bone marrow cell culture

Takanobu Fukunaga, Kosaku Kurata, Junpei Matsuda, Hidehiko Higaki

Research output: Contribution to journalArticle

Abstract

Bone is continuously subjected to repetitive loading, which leads to microdamage even if the strain level is within physiological range. The damaged site must be sensed and promptly repaired by remodeling process ; otherwise the accumulation of microdamage results in bone fracture. Osteocytes neighboring the microdamage should play an important role in detecting local mechanical environment and in initiating bone remodeling process, i.e. osteoclastic resorption of the damaged area. The aims of this study were, therefore, to establish a relevant in vitro model for studying mechanical responses of stretched osteocytes in three-dimensional culture. We established a loading apparatus in which osteocyte-like cell line MLO-Y4 cells were three-dimensionally cultured inside collagen gel and subjected to cyclic stretching in over-physiological strain level. Excessive stretching at 10 000 με damaged the gel-embedded osteocyte, resulting in significant amount of cell death. Conditioned medium obtained from the damaged osteocyte culture induced significant amount of TRACP-positive cells. It demonstrates that soluble factors secreted by the damaged osteocytes have a potential to promote osteoclastic cell formation, and further suggests that the local death of osteocytes provides an important mechanism to target remodeling to microdamaged site.

Original languageEnglish
Pages (from-to)547-554
Number of pages8
JournalNihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C
Volume73
Issue number2
Publication statusPublished - Feb 1 2007
Externally publishedYes

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Cell culture
Stretching
Bone
Gels
Cells
Cell death
Collagen

All Science Journal Classification (ASJC) codes

  • Mechanics of Materials
  • Mechanical Engineering
  • Industrial and Manufacturing Engineering

Cite this

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AU - Kurata, Kosaku

AU - Matsuda, Junpei

AU - Higaki, Hidehiko

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