Studies on phytochemicals in fruits and vegetables on diabetes and insulin resistance

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K07424
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Food science
• Research Institution: Utsunomiya University
• Principal Investigator: YAGASAKI Kazumi 宇都宮大学, バイオサイエンス教育研究センター, 特任教授 (20166474)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: ２型糖尿病 / グルコース輸送体 / インスリン抵抗性 / 耐糖能 / 高尿酸血症 / GLUT4 / AMPK / Akt

Outline of Final Research Achievements

The number of patients with diabetes, especially type 2 diabetes (T2D), is increasing worldwide, and the increase in socioeconomic burden of diabetes will be inevitable. In the present study, we have tried to search edible phytochemicals that possess potentials to prevent the increase in postprandial blood glucose levels. The muscle is the largest tissue in our body and plays an important role in glucose homeostasis. Thus, adopting cultured L6 myotubes, we have contrived a simple and rapid glucose uptake assay system. Several phytochemicals were found to promote glucose uptake through glucose transporter 4 (GLUT4) translocation to plasma membrane of muscle cells via activation of AMPK and/or Akt signaling pathway(s). They also suppressed hyperglycemia and improved glucose intolerance in T2D model mice. Some kinds of phytochemicals suppressed insulin resistance as well as hyperuricemia and hyperglycemia, suggesting that phytochemicals seem to be preventive and/or remedial for T2D.

Free Research Field

食品科学

Academic Significance and Societal Importance of the Research Achievements

２型糖尿病は世界的に増加しており、合併症も含め社会経済負担増大が懸念される。糖尿病でもないが正常でもない「未病」の状態を、本当の糖尿病にしないことが望まれる。本研究では、果菜由来の植物化学物質（ファイトケミカル）に着目してこの点の解析を試みた。筋肉は体の中で最大の組織であり、血中からのグルコース取り込み（GU）を促進して食後血糖値上昇の正常化に大きく寄与する。培養筋細胞で作用機構を含めて検討したところ複数の成分が筋肉細胞でGUを促進し、２型糖尿病モデルマウスでの血糖値上昇や耐糖能異常改善作用、高尿酸血症を改善しつつインスリン抵抗性を弱める作用等が見出され、今後の学術的・社会的意義が期待される。