Leucine supplementation after mechanical stimulation activates protein synthesis via L‐type amino acid transporter 1 in vitro
-
- Naoya Nakai
- Department of Nutrition University of Shiga Prefecture Hikone Shiga Japan
-
- Fuminori Kawano
- Graduate School of Health Sciences Matsumoto University Matsumoto Nagano Japan
-
- Taro Murakami
- Department of Nutrition Shigakkan University Ohbu Aichi Japan
-
- Ken Nakata
- Medicine for Sports and Performing Arts, Graduate School of Medicine Osaka University Toyonaka Osaka Japan
-
- Kazuhiko Higashida
- Department of Nutrition University of Shiga Prefecture Hikone Shiga Japan
書誌事項
- 公開日
- 2017-09-18
- 資源種別
- journal article
- 権利情報
-
- http://onlinelibrary.wiley.com/termsAndConditions#vor
- DOI
-
- 10.1002/jcb.26371
- 公開者
- Wiley
この論文をさがす
説明
<jats:title>Abstract</jats:title><jats:sec><jats:label/><jats:p>Branched‐chain amino acid supplements consumed following exercise are widely used to increase muscle mass. Although both exercise (ie, mechanical stimulation) and branched‐chain amino acid leucine supplementation have been reported to stimulate muscle protein synthesis by activating the mammalian target of rapamycin (mTOR) signaling pathway independently, the mechanisms underlying their synergistic effects are largely unknown. Utilizing cultured differentiated C2C12 myotubes, we established a combination treatment model in which the cells were subjected to cyclic uniaxial mechanical stretching (4 h, 15%, 1 Hz) followed by stimulation with 2 mM leucine for 45 min. Phosphorylation of p70 S6 kinase (p70S6K), an mTOR‐regulated marker of protein translation initiation, was significantly increased following mechanical stretching alone but returned to the baseline after 4 h. Leucine supplementation further increased p70S6K phosphorylation, with a greater increase observed in the stretched cells than in the non‐stretched cells. Notably, the expression of L‐type amino acid transporter 1 (LAT1), a stimulator of the mTOR pathway, was also increased by mechanical stretching, and siRNA‐mediated knockdown partially attenuated leucine‐induced p70S6K phosphorylation. These results suggest that mechanical stretching promotes LAT1 expression and, consequently, amino acid uptake, leading to enhanced leucine‐induced activation of protein synthesis. LAT1 has been demonstrated to be a point of crosstalk between exercise‐ and nutrition‐induced skeletal muscle growth.</jats:p></jats:sec>
収録刊行物
-
- Journal of Cellular Biochemistry
-
Journal of Cellular Biochemistry 119 (2), 2094-2101, 2017-09-18
Wiley
