Analysis of the function of arginine as a signaling molecule to stimulate protein synthesis

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K05501
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38050:Food sciences-related
• Research Institution: Utsunomiya University
• Principal Investigator: YOSHIZAWA Fumiaki 宇都宮大学, 農学部, 教授 (10269243)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: アルギニン / タンパク質合成 / 骨格筋 / C2C12細胞 / S6K1 / 4E-BP1 / mTOR / CASTOR1

Outline of Final Research Achievements

The purpose of this study was to clarify the regulatory role of arginine as a signaling molecule to stimulate protein synthesis in skeletal muscle. Mice experiments suggested that arginine activated mTORC1 in skeletal muscle. In addition, the results obtained from experiments using C2C12 myotubular cells suggested that the stimulating effect of arginine on protein synthesis was mediated by the mTORC1 pathway. The effects of ornithine and citrulline, which were produced during arginine metabolism, on protein synthesis were also examined using C2C12 myotubular cells, but their involvement was not confirmed. Furthermore, nitric oxide, produced from arginine by nitric oxide synthase, was also suggested not to be involved in arginine-induced increases in protein synthesis.

Free Research Field

栄養生化学

Academic Significance and Societal Importance of the Research Achievements

アルギニンは、代謝産物である一酸化窒素を介して、成長ホルモンの分泌促進、免疫機能の向上、脂肪代謝の促進など、生体内で種々の作用に関与していることが知られている。さらに、近年アルギニンがタンパク質合成を促進する作用をもつ可能性が示され、運動時のサプリメント等に広く利用されている。しかし、アルギニンの骨格筋タンパク質合成に対する作用を調べた研究は殆どなく、本研究の成果は栄養素によるタンパク質代謝調節に関する基礎研究のみならず、サプリメントや栄養剤等の開発に関する応用研究にも資するものである。