素通过mTOR信号通路调节骨肌肉纤维类型的形成
Min Zhou1, Yihan Wei1, Yue Feng1
1State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
International journal of molecular sciences
|June 19, 2024
概括
补充L-氨酸 (Arg) 增强了小鼠的慢肌纤维和线粒体功能. 这种氨基酸促进耐力,并激活mTOR通路,改善肌肉健康和性能.
科学领域:
- 肌肉生理学和线粒体生物学.
- 营养生物化学和代谢途径.
背景情况:
- 骨肌纤维类型的组成会影响肉质和人类的体力表现.
- L-氨酸 (Arg) 与缓慢缩纤维形成有关,但机制尚不清楚.
- 了解Arg在肌肉适应中的作用对于健康和运动优化至关重要.
研究的目的:
- 研究L-氨酸 (Arg) 对骨肌肉纤维类型组成和线粒体功能的影响.
- 阐明mTOR信号通路在Arg介导的肌肉适应中的作用.
- 确定Arg补充剂是否可以提高耐力和肌肉质量.
主要方法:
- 在体内使用C56BL/6J的研究中,小鼠在7周内接受了不同Arg度的饮食.
- 在体外研究中,使用培养的C2C12菌根管接受了Arg和/或mTOR抑制剂拉帕米的治疗.
- 分析包括运动表现,SDH酶活性和基因表达 (MyHC I,MyHC IIA,PGC-1α,NRF1,TNnt1,TFAM,MEF2C).
主要成果:
- 阿格补充剂改善了耐力表现,增加了小鼠骨肌中的SDH活性.
- 在Arg上调节的慢动纤维基因 (MyHC I,MyHC IIA) 和线粒体生物发生基因 (PGC-1α,NRF1).
- 阿尔格激活了mTOR信号通路,其对基因表达的影响被拉巴胺素阻止.
结论:
- L-氨酸 (Arg) 促进向缓慢抽的肌肉纤维的转变,并增强线粒体功能.
- mTOR信号通路对于Arg对骨肌肉的有益影响至关重要.
- 补充是一种改善肌肉性能和健康的潜在策略.
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