Mechanism and exercise conditions for mitochondrial memory of exercise experience

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K21749
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 59:Sports sciences, physical education, health sciences, and related fields
• Research Institution: Kanazawa University
• Principal Investigator: Masuda Kazumi 金沢大学, 人間科学系, 教授 (50323283)
• Co-Investigator(Kenkyū-buntansha): 芝口 翼 金沢大学, GS教育系, 講師 (40785953)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: 運動 / エピジェネティクス / 記憶 / 骨格筋 / ミトコンドリア

Outline of Final Research Achievements

In the present study, we examined whether past training (TR) experience affects not only muscle hypertrophy but also mitochondrial adaptability. Experimental animals carried out either climbing TR (RT) or running TR (ET). Skeletal muscle (m. plantaris) was analyzed at each time point under the conditions of after-TR, de-TR and after re-start of TR. In the ET condition, as a phenotype of TR memory, muscle fibers were hypertrophied after re-TR compared to the first TR. The responsiveness of HSPs involved in protein synthesis/degradation also changed as similar matter with muscle fiber CSA. Although a correlation was obtained between the number of myonuclei and mitochondrial protein expression, global validation of chromatin failed to detect changes in histone modifications, so RNAseq and ChIP analysis have been underway.

Free Research Field

ポーツ科学、体育、健康科学およびその関連分野

Academic Significance and Societal Importance of the Research Achievements

骨格筋には筋記憶と称される機能、すなわち過去のトレーニング（TR）経験が骨格筋に保持され、再TR時の骨格筋適応を促進させることが示唆されている。こうした機構がミトコンドリア適応にも及ぶのかの科学的証拠は存在しない。骨格筋の収縮力と代謝能力の記憶メカニズムが明らかになれば、運動への応答性の個人差の分子メカニズム、運動で獲得した形質の保存と遺伝性の探求等、運動を切り口にした骨格筋のエピジェネティクス研究を発展させる可能性を持つ。さらに、運動のエピジェネティクス制御の解明は、人々の運動実施方法や習慣化を通した健康増進や疾病予防に資するための基礎実験として、新たな細胞機能向上を提唱することとなる。