Mechanisms of abnormal blood pressure response to exercise in the brain insulin resistance observed in Alzheimer's disease and novel physiological actions of insulin

2023 Fiscal Year Final Research Report

• Project/Area Number: 20H04083
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 59020:Sports sciences-related
• Research Institution: Chubu University
• Principal Investigator: Hotta Norio 中部大学, 生命健康科学部, 准教授 (60548577)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: アルツハイマー病 / インスリン抵抗性 / 運動時循環調節 / 運動昇圧反射 / セントラルコマンド / 筋機械受容器反射 / 筋代謝受容器反射 / メカノバイオロジー

Outline of Final Research Achievements

The purpose of this study was to investigate the effects of central insulin resistance observed in Alzheimer's disease (AD) on the exercise pressor response. Experiments simulating acute insulin resistance revealed that the “gain” of the neural center in the exercise pressor reflex was potentiated (input [stimulus] < output [pressor response]). In cognitively impaired rats with chronically induced brain insulin resistance, it has been suggested that the neural central gain of the exercise pressor reflex is reduced (input > output). We further tested whether central insulin administration modifies the attenuation of the pressor response induced by chronic insulin resistance. However, the expected results have not yet been obtained. These results may be useful in developing an exercise prescription and exercise guidance for AD patients with cerebral insulin resistance.

Free Research Field

運動生理学

Academic Significance and Societal Importance of the Research Achievements

学術的意義： アルツハイマー病(AD)の病態である中枢インスリン機能異常により，少なくとも運動昇圧反射中枢のゲインが変わり得ることを世界に先駆けて明らかにした．
社会的意義：ADの発症機序に基づく根治療法は未だ確立されていないが，定期的な身体運動は脳内インスリン抵抗性を改善し，認知機能を改善させることが報告されている．本研究は，慢性的な脳内インスリン抵抗性が運動昇圧応答を弱める，つまり活動筋への酸素供給不足を招き，運動耐用能を低下させることを示唆した．本知見は，健康運動の指導者が，ADに観察される脳内インスリン抵抗性が高い患者に対する運動処方を作成，ならびに運動指導する際の一助となり得る．