{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T23:43:56Z","timestamp":1772322236049,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2022,7,4]],"date-time":"2022-07-04T00:00:00Z","timestamp":1656892800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Society for the Promotion of Science (JSPS)","award":["18H05254"],"award-info":[{"award-number":["18H05254"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The anisotropic microstructure of bone, composed of collagen fibers and biological apatite crystallites, is an important determinant of its mechanical properties. Recent studies have revealed that the preferential orientation of collagen\/apatite composites is closely related to the direction and magnitude of in vivo principal stress. However, the mechanism of alteration in the collagen\/apatite microstructure to adapt to the mechanical environment remains unclear. In this study, we established a novel ex vivo bone culture system using embryonic mouse femurs, which enabled artificial control of the mechanical environment. The mineralized femur length significantly increased following cultivation; uniaxial mechanical loading promoted chondrocyte hypertrophy in the growth plates of embryonic mouse femurs. Compressive mechanical loading using the ex vivo bone culture system induced a higher anisotropic microstructure than that observed in the unloaded femur. Osteocytes in the anisotropic bone microstructure were elongated and aligned along the long axis of the femur, which corresponded to the principal loading direction. The ex vivo uniaxial mechanical loading successfully induced the formation of an oriented collagen\/apatite microstructure via osteocyte mechano-sensation in a manner quite similar to the in vivo environment.<\/jats:p>","DOI":"10.3390\/ijms23137423","type":"journal-article","created":{"date-parts":[[2022,7,4]],"date-time":"2022-07-04T11:15:05Z","timestamp":1656933305000},"page":"7423","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Novel Ex Vivo Bone Culture Model for Regulation of Collagen\/Apatite Preferential Orientation by Mechanical Loading"],"prefix":"10.3390","volume":"23","author":[{"given":"Ryota","family":"Watanabe","sequence":"first","affiliation":[{"name":"Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan"},{"name":"Teijin Nakashima Medical Co., Ltd., 688-1 Joto-Kitagata, Higashi-ku, Okayama 709-0625, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8427-7124","authenticated-orcid":false,"given":"Aira","family":"Matsugaki","sequence":"additional","affiliation":[{"name":"Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0081-0591","authenticated-orcid":false,"given":"Takuya","family":"Ishimoto","sequence":"additional","affiliation":[{"name":"Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2773-072X","authenticated-orcid":false,"given":"Ryosuke","family":"Ozasa","sequence":"additional","affiliation":[{"name":"Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9804-4786","authenticated-orcid":false,"given":"Takuya","family":"Matsumoto","sequence":"additional","affiliation":[{"name":"Department of Biomaterials, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1, Shikata-cho, Kita-ku, Okayama 700-8558, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8052-1698","authenticated-orcid":false,"given":"Takayoshi","family":"Nakano","sequence":"additional","affiliation":[{"name":"Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,4]]},"reference":[{"key":"ref_1","unstructured":"Cabinet Office (2021, October 29). 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