Mechanisms of different effects of muscle protein metabolisms in oral administration and cultured cells by methionine

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K07727
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Food science
• Research Institution: Iwate University
• Principal Investigator: Nagasawa Takashi 岩手大学, 農学部, 教授 (80189117)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 骨格筋タンパク質 / タンパク質分解 / アミノ酸 / メチオニン / オートファジー / C2C12培養筋管細胞

Outline of Final Research Achievements

Oral administration of Met to rats increased blood levels of Met metabolites, but did not alter insulin levels or ghrelin levels. However, when C2C12 myotubes were treated with Met, no suppression of degradation was observed, and neither autophagy activity was reduced, but rather autophagy dysfunction was induced. The C2C12 myotubes were treated with metabolites of Met, but they did not suppress degradation. These results suggested that the suppression of muscle protein degradation by Met was not caused by the metabolites or hormones. We examined the effect of Met on the degradation rate of skeletal muscle protein in ex vivo. The degradation rate in fast twitch muscle protein was suppressed by Met. Therefore the regulation of skeletal muscle protein metabolism by Met may differ between fast and slow twitch muscles..

Free Research Field

栄養化学

Academic Significance and Societal Importance of the Research Achievements

ロイシンのタンパク質同化作用は多くの研究があるが、その他のアミノ酸については不明の点が多い。メチオニンはラットに対する作用と培養細胞に対する作用が異なることが明らかになり、その原因が骨格筋の種類による可能性が考えられるということは、加齢に伴う骨格筋萎縮防止を効果的に行うための基礎的知見になると考えられる。同化作用のあるアミノ酸の混合物が高齢化社会における動ける体作りに貢献する。