线粒体生物能学与肌纤维细胞蛋白质合成率没有关联
Andrew M Holwerda1,2, Marlou L Dirks1,3, Pierre-Andre Barbeau2
1NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands.
Journal of cachexia, sarcopenia and muscle
|July 15, 2024
概括
线粒体功能,包括氧化酸化和活性氧物种,似乎没有调节肌肉蛋白质合成或质量. 这些发现表明,其他因素对人类和小鼠的肌肉调节更为关键.
科学领域:
- 细胞生物学 细胞生物学
- 运动生理学 运动生理学
- 线粒体生物学 线粒体生物学
背景情况:
- 线粒体是参与细胞平衡和蛋白质合成的重要器官.
- 线粒体功能,包括氧化酸化和反应性氧物种 (ROS) 排放,都与调节蛋白质合成有关.
研究的目的:
- 调查线粒体生物能学 (氧化酸化和ROS排放) 是否调节每日肌肉蛋白质合成和骨肌肉质量.
- 检查这些监管作用在不同的身体活动水平,包括自由生活,床上休息,和炼训练.
主要方法:
- 评估了年轻和老年男性透肌肉纤维中的线粒体氧化酸化和H2O2排放.
- 测量了综合的每日肌肉蛋白质合成率和骨肌肉质量变化.
- 利用转基因小鼠 (MCAT) 评估线粒体ROS排放与蛋白质合成之间的直接关系.
主要成果:
- 在年轻男性中,氧化酸化和H2O2排放与在自由生活或床上休息条件下的肌肉蛋白质合成无关.
- 在接受运动训练的老年男性中,只有亚最大氧化酸化与肌纤维细胞蛋白质合成具有积极的关联.
- 线粒体参数的变化和MCAT小鼠的修改都没有影响肌肉质量或蛋白质合成率.
结论:
- 线粒体的氧化酸化和反应性氧气排放似乎不是肌肉蛋白质合成的关键调节者.
- 这些线粒体因素似乎在不同身体活动状态的骨肌肉质量调节中没有发挥显著作用.
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