Accelerated recruitment of bone marrow cells to the repair site in the parabiosed rat by LIPUS

2021 Fiscal Year Final Research Report

• Project/Area Number: 17K11922
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: Kanagawa Dental College
• Principal Investigator: Takeuchi Ryohei 神奈川歯科大学, 歯学部, 特任教授 (30236442)
• Co-Investigator(Kenkyū-buntansha): 熊谷 研 横浜市立大学, 医学部, 准教授 (10468176) ; 川股 亮太 神奈川歯科大学, 歯学部, 診療科教授 (40329199) ; 高垣 裕子 神奈川歯科大学, 歯学部, 特任教授 (60050689) ; 日高 恒輝 神奈川歯科大学, 歯学部, 助手 (90760041)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: 骨折治癒 / 低出力超音波 / 力学刺激 / 全身性効果 / 液性因子

Outline of Final Research Achievements

It is essential to have enough cells for bone regeneration. We have reported LIPUS exposure of fractured femur and tooth extraction socket recruit cells for regeneration through peripheral blood vessels from the remote sites to the wound in mice and rats, respectively (Kumagai, Takeuchi et al., 2011 and Hidaka et al., 2015). In this study, we confirmed LIPUS exerted its anabolic action not only locally but also systemically on the implanted beta-TCP discs in the back of rats, which were not directly treated with LIPUS and elucidated the molecular mechanisms. Message expression and (immuno-)histochemical localization of proteins and cells using antibodies against M1 and M2 macrophage, and cytokines showed the involved entities. In the discs of LIPUS-untreated parabiosed rat, we observed invaded cells including M2 macrophages and blood vessels present in numbers between those of the LIPUS-exposed and the control rats. We were able to present the systemic effect of LIPUS.

Free Research Field

整形外科

Academic Significance and Societal Importance of the Research Achievements

低出力超音波の照射は骨折治癒期間を約40％短縮することが知られ、国内でも標準治療として用いられている。我々は、これまでに、治癒の促進が局所の細胞の活性化、サイトカイン産生ばかりでなく骨髄細胞の循環を通じて全身性にも誘導されることを示した。これは、炎症の制御が健康寿命に大きな役割を持つことが判明した現在広範な応用価値を示唆するもので、詳細なメカニズムの理解は、薬に頼らない医療の突破口としての可能性を約束する。