Strategies to control insulin resistance based on prevention of weakened immunoglobulin A coating of commensal gut bacteria

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K11580
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 59040:Nutrition science and health science-related
• Research Institution: Okayama University
• Principal Investigator: Tsuruta Takeshi 岡山大学, 環境生命科学学域, 准教授 (90728411)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: インスリン抵抗性 / 免疫グロブリンA / 腸内細菌

Outline of Final Research Achievements

Insulin resistance, a major factor in the pathogenesis of type 2 diabetes, is associated with a disturbance in the relationship between IgA, a major antibody in gut, and commensal gut bacteria. In this study, we searched for food materials that eliminate the disturbance and verified the effect on prevention of insulin resistance. As a result, while high intake of animal fat causes a disturbance in the relationship between IgA and gut bacteria, replacing the fatty acid composition of animal fat with medium-chain fatty acids alleviated the disturbance and also alleviated the symptoms of insulin resistance. It was also found that consumption of a dietary fiber together with animal fat improved the disturbance in the relationship between IgA and gut bacteria, as well as insulin resistance.

Free Research Field

食品機能化学

Academic Significance and Societal Importance of the Research Achievements

本研究成果から一部の難消化性糖質の摂取や動物性油脂の代替油脂として消化吸収性の高い油脂を摂取することにより腸内細菌に結合する腸管IgA量が増加し、特定の腸内細菌に対する腸管IgAの結合性が変化することが明らかとなった。また、これらの作用が糖代謝機能の低下抑制に関与していることが示された。本知見を応用し、腸内細菌と腸管IgAの正常な関係性を維持し、2型糖尿病予防に有用な食品素材の探索やその組み合わせを提案していくことが期待できる。