Elucidation of the mechanism of muscle degeneration using a mouse model and search for biomarkers of muscle regeneration using MRI

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K09213
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56020:Orthopedics-related
• Research Institution: Keio University
• Principal Investigator: Tsuji Osahiko 慶應義塾大学, 医学部(信濃町), 特任准教授 (70424166)
• Co-Investigator(Kenkyū-buntansha): 畑 純一 東京慈恵会医科大学, 医学部, 講師 (00568868) ; 依田 昌樹 慶應義塾大学, 医学部(信濃町), 特任助教 (30464994) ; 藤吉 兼浩 独立行政法人国立病院機構村山医療センター(臨床研究部), 整形外科, 医長 (80365303)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 筋変性 / 腱板損傷

Outline of Final Research Achievements

We created a mouse rotator cuff injury/degeneration model (rotator cuff component muscle dissection, denervation, and osteotomy) that efficiently recapitulates muscle fatty degeneration. Furthermore, a more clinically relevant mouse rotator cuff injury model was created using only rotator cuff injury without denervation or osteotomy, and was successfully reproduced using old (>50-week-old) mice. As a result, we further confirmed marked degeneration and fatty degeneration of the subscapularis muscle among the rotator cuff component muscles.

Free Research Field

整形外科

Academic Significance and Societal Importance of the Research Achievements

小動物マウスで安定した腱板損傷作成に成功し、その筋変性の病態の詳細な解析を行った。腱板構成筋（棘上筋、棘下筋、肩甲下筋）の中で、棘下筋に有意な重量減少並びに脂肪変性が認められた。一方で、線維化については各筋間で差は無かった。また、マウス下肢筋を用いた拡散MRI撮像条件を検討し、小動物を用いた筋変性解析の基盤を構築できた。