Importance of motor neuron in determining muscle fiber types during muscle injury recovery

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05896
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 42010:Animal production science-related
• Research Institution: Azabu University
• Principal Investigator: Sawano Shoko 麻布大学, 生命・環境科学部, 教授 (60403979)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 損傷筋 / マウス / 筋線維 / 回復

Outline of Final Research Achievements

Skeletal muscle has a high regenerative capacity and recovers quickly after injury. It is known that myofiber type composition can be altered by environmental factors such as exercise training. However, the involvement of myofiber type composition and motor innervation after muscle regeneration is still unknown. In this study, we investigated how myofiber type composition changes after muscle regeneration by observing myofiber type composition over time in the post-injury tibialis anterior muscle of mice with multiple types of induced muscle injury. We found that after injury, myofiber type composition transiently changed from 2B to 2X and returned to a composition similar to that of the non-injured zone over time. The relevance to motor neurons needs to be further investigated.

Free Research Field

食品科学

Academic Significance and Societal Importance of the Research Achievements

本成果は筋損傷後の回復過程における骨格筋再生について、その挙動の一端を明らかにしたものである。本研究成果を起点として、筋線維タイプの細胞レベルでの変化と、それに続く運動神経支配による筋線維タイプ移行機構のしくみが明らかになることで、将来的に、食味性の高い良質な食肉を創出できるだけでなく、ヒトにおいても高齢者の自立歩行のための筋持久力の向上など、様々な分野に応用されることが期待できる。