The investigation for the effect of spaceflight on muscle-bone crosstalk in mice

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K21000
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0906:Surgery related to the biological and sensory functions and related fields
• Research Institution: Kindai University
• Principal Investigator: Ohira Takashi 近畿大学, 医学部, 助教 (40633532)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: 微小重力 / マウス / 骨格筋 / プロテオミクス

Outline of Final Research Achievements

We analyzed the protein expression profile of skeletal muscles of mice raised under microgravity or artificial 1-g on the International Space Station. The altered protein expression profiles in response to gravitational unloading indicated that the shift of fiber phenotype toward fast-twitch type in soleus and gastrocnemius muscles was significantly induced. Simultaneously, the expression levels of proteins involved in blood coagulation and fibrinolysis increased in the gravitational-unloaded muscles. Fibrinolysis plays important roles in removing fibrin clots generated by the blood coagulation system as well as in facilitating skeletal muscle repair following injury. However, the roles of the fibrinolysis system in the gravitational-unloaded muscles are still unknown. This need to be elucidated in the future to expand our understanding of the mechanism underlying the skeletal muscle responses to gravitational unloading.

Free Research Field

骨格筋生理学

Academic Significance and Societal Importance of the Research Achievements

月・火星有人探査の実現性が高まる中、宇宙飛行士の健康維持だけでなく業務遂行の安全性や確実性を高めるためにも、微小重力曝露に伴う運動器機能低下に対する予防策の確立は喫緊の課題である。本研究では、国際宇宙ステーション内の微小重力または人工1-g環境で飼育したマウスのヒラメ筋、長趾伸筋、腓腹筋のタンパク発現プロファイルを解析し、宇宙飛行中のマウスを人工1-g環境で飼育することは、骨格筋の萎縮だけでなく、速筋化に伴う代謝特性の変化を抑制するのにも有効であることを確認した。