同度收缩诱导REDD1表达在非收缩肌肉中的短暂增加,部分是通过葡萄糖皮质类药物
1Department of Nutrition, Shigakkan University, Obu, Japan.
Physiological reports
|June 6, 2023
概括
肌肉收缩通过增加REDD1 (调节发育和DNA损伤1) 来暂时降低非收缩的小鼠肌肉中的蛋白质合成. 这种反应可能会重定向氨基酸以支持肌肉修复和生长.
科学领域:
- 肌肉生理学 肌肉生理学
- 分子生物学分子生物学
- 内分泌学 在内分泌学.
背景情况:
- 肌肉收缩对于肌肉适应和生长至关重要.
- 调节发育和DNA损伤1 (REDD1) 是mTORC1信号的抑制剂,是肌肉蛋白质合成的关键调节剂.
- 了解肌肉收缩如何影响REDD1表达对于理解肌肉适应是很重要的.
研究的目的:
- 为了研究肌肉收缩是否会诱导小鼠肌肉中的REDD1表达.
- 为了检查肌肉收缩对mTORC1信号和蛋白质合成的影响.
- 确定葡萄糖皮质激素在这种反应中的作用.
主要方法:
- 在小鼠中,单侧异比电刺激胃半肌肌.
- 测量肌肉蛋白质合成,mTORC1信号传递 (4E-BP1酸化),以及REDD1蛋白和mRNA水平在收缩后的各种时间点.
- 用RU-486,一种葡萄糖皮质体受体对抗剂来评估葡萄糖皮质体的作用.
主要成果:
- 收缩后0个小时和3个小时肌肉蛋白质合成变得模糊,这与mTORC1信号的减少有关.
- 在收缩后3小时,对侧面的非收缩肌肉中,REDD1蛋白和mRNA水平增加.
- 与RU-486的葡萄糖皮质体受体对抗作用减弱了非收缩肌肉中的REDD1诱导.
结论:
- 肌肉收缩会在对侧,非收缩的肌肉中诱导一个暂时的合成抵抗.
- 这种反应涉及REDD1表达的诱导,可能由葡萄糖皮质体介导.
- 这些发现表明营养分化的机制,可能会增强氨基酸的可用性,为收缩的肌肉支持蛋白质合成.
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