短期不使用不会影响后吸收或食后肌肉蛋白的分量分解率
George F Pavis1, Doaa R Abdelrahman2,3, Andrew J Murton2,3
1Nutritional Physiology Research Group, Public Health & Sport Sciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK.
Journal of cachexia, sarcopenia and muscle
|July 11, 2023
概括
两天的腿部固定不动并没有改变肌肉蛋白质分解率. 短期不使用期间的肌肉损失主要是由于肌肉蛋白质合成减少和对氨基酸的合成抵抗.
科学领域:
- 肌肉生理学 肌肉生理学
- 代谢研究的研究.
- 废弃使用缩.
背景情况:
- 短期不使用时的肌肉缩并不能完全由肌肉蛋白质合成率的降低来解释.
- 在不使用期间调查肌肉蛋白质分解率对于理解肌肉损失至关重要.
- 这项研究研究了固定对肌肉蛋白质分解和合成的影响.
研究的目的:
- 为了确定2天单边膝关节固定是否会影响肌肉蛋白分数分解率 (FBR).
- 在吸收后和模拟的食后状态下评估FBR和分数合成速率 (FSR).
- 阐明在短期不使用期间驱动肌肉蛋白平衡的机制.
主要方法:
- 23名健康的男性接受了48小时的单方面膝关节固定.
- 使用了稳定同位素 (l-[15N]-phenylalanine和l-[环-2H5]-phenylalanine) 的连续静脉注射.
- 收集了肌肉活检和血液样本,以确定FBR和FSR在吸收后 (FAST) 和养后 (FED) 状态.
主要成果:
- 在FAST或FED条件下,固定不动并没有影响肌肉蛋白质分解率.
- 在FAST和FED状态下,肌肉蛋白质合成率在固定状态下显著下降.
- 净肌肉蛋白平衡下降,FED状态下降更明显.
结论:
- 两天的腿部固定不动不会改变肌肉蛋白质分解率.
- 减少肌肉蛋白质合成和对氨基酸的合成抵抗是短期不使用期间肌肉蛋白质负平衡的主要驱动因素.
- 这些发现凸显了肌肉蛋白质合成在预防不使用缩方面的重要性.
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