Investigation of association between gut microbiota and insulin resistance by high-fat diet

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K01870
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Applied health science
• Research Institution: Juntendo University
• Principal Investigator: Kanazawa Akio 順天堂大学, 医学部, 准教授 (30407259)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 腸内細菌叢 / インスリン抵抗性 / 高脂肪食 / バクテリアルトランスロケーション

Outline of Final Research Achievements

We recruited 21 healthy non-obese men and evaluated lipopolysaccharide (LPS) binding protein (LBP), a marker of endotoxemia and gut microbiota before and after 6-day high-fat diet consisting of saturated fatty acids (60-70%). By using a 2-step hyperinsulinemic euglycemic clamp, we evaluated tissue specific insulin sensitivity. After the high-fat diet, insulin sensitivity in liver and muscle was significantly decreased. In addition, circulating LBP was significantly increased after the high-fat diet. Baseline relative abundance of Bacteroidetes, LPS-producing Gram-negative gut microbiota, was negatively　correlated to metabolic clearance rate of insulin and insulin sensitivity in　muscle. In conclusion, short-term high-fat diet decreased insulin sensitivity and increased metabolic endotoxemia.

Free Research Field

腸内細菌叢

Academic Significance and Societal Importance of the Research Achievements

本研究は健常人でも短期間の高脂肪食摂取はインスリン感受性を低下させるとともに、腸管内の毒素であるエンドトキシンを血液中へ移行させる可能性を示している。
また、バクテロイデス門の細菌叢を多く有するほど、高脂肪食負荷後にインスリン感受性は低下した。これらの結果は腸内細菌叢の構成により、食事指導の方法を考慮する必要があり、将来のメタボリックシンドロームの予防につながる研究成果といえる。