Elucidation of the pathophysiology of frozen shoulder and development of new treatment methods focusing on retinoid metabolism

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K09591
• 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: Tohoku University
• Principal Investigator: Eiichi Chimoto 東北大学, 医学系研究科, 大学院非常勤講師 (30810593)
• Co-Investigator(Kenkyū-buntansha): 萩原 嘉廣 東北大学, 医学系研究科, 准教授 (90436139)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 関節拘縮 / 五十肩 / 関節包 / ビタミンA / 脂質 / 線維化 / 軟骨化生 / 血管新生

Outline of Final Research Achievements

The frozen shoulder causes severe pain and joint contracture, and greatly reduces the quality of life of patients. The pathophysiology of frozen shoulder is thought to be inflammation and fibrosis of the joint capsule, but the pathogenesis is still unknown and there is no fundamental treatment. Based on comprehensive protein analysis of frozen shoulder tissues, the principal investigator's group has proposed the involvement of chondrogenesis and decreased vitamin A metabolism as new pathological conditions. In this study, the effects of hypovitaminosis A on joint contracture were examined using a rat knee immobilization model. Factors involved in fibrosis, chondrogenesis, and angiogenesis were increased in the joint capsule of hypovitamin A rats, and joint capsule stiffness was observed. Vitamin A deficiency may produce contracture-related changes in the joint capsule.

Free Research Field

整形外科

Academic Significance and Societal Importance of the Research Achievements

五十肩の病態は未だ解明されておらず、根本的な治療法もない。本研究ではビタミンA代謝に着目し、低ビタミンAラットモデルを作成し関節拘縮の病態解析を行った。本研究の結果からビタミンAの低下が関節包に線維化、軟骨化生、血管新生および関節包の硬化を生じ、関節拘縮に関与する可能性が示された。ビタミンAと関節拘縮との関連が明らかとなれば新たな治療薬の開発につながるほか、食生活の改善など身近な対応策によって五十肩を予防できる可能性がある。病気を治す従来の治療から予防治療へのシフトが可能となり、医療費の抑制の観点からも社会的意義がある。