Exercise-dependent regulation of skeletal muscle-derived exosomes

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06442
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 42030:Animal life science-related
• Research Institution: Toyo University
• Principal Investigator: Nedachi Taku 東洋大学, 生命科学部, 教授 (50375200)
• Co-Investigator(Kenkyū-buntansha): 宮西 伸光 東洋大学, 食環境科学部, 教授 (80372720)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 骨格筋 / エクソソーム / miRNA / 運動

Outline of Final Research Achievements

The purpose of this study was to focus on exosomes, which are a type of EVs, and to clarify how exosomes secreted by skeletal muscle are regulated by exercise. Initially, we applied electrical pulse stimulation (EPS) to C2C12 myotubes to induce cell contraction, and exosomes secreted into the culture supernatant were analyzed. RNA-seq analysis revealed numerous types of miRNAs are present in exosomes, and some miRNAs are fluctuated by EPS. Some of these miRNAs have been reported to target muscle differentiation-related genes, suggesting that exercise-dependently released exosomes may be involved in muscle differentiation. In fact, we found that exosomes secreted from EPS-treated C2C12 myotube cells regulate the expression of differentiation-related genes in myoblasts. Overall, it can be speculated that exercise promotes qualitative changes in released exosomes from skeletal muscles, especially changes in the encapsulated miRNA profile, thereby controlling muscle differentiation.

Free Research Field

細胞生物学

Academic Significance and Societal Importance of the Research Achievements

適切な運動を行うことは、骨格筋の量や質を改善するなど多くの利点があるが、適切な運動がどうやって健康を促進するのかについてはまだ不明な点が多く残っている。今回の研究では、骨格筋から放出される「細胞外小胞」という小分子の性質が運動によって変化し、この性質の変化によって骨格筋の量が調節されているのではないかという新しい結果を得た。骨格筋の量は加齢によって減少することが分かっており、これが加齢にともなって転倒しやすくなる原因のひとつではないかと考えられている。本研究をさらに進めることで、加齢にともなう骨格筋量減少を防ぐ方法の開発につながっていくものと期待される。