Muscle satellite cell and atypical myogenic progenitor response following exercise
Muscle satellite cell and atypical myogenic progenitor response following exercise
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DOI：
10.1002/mus.20995
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发表时间：
2008-05-01
期刊：
影响因子：
3.4
通讯作者：
Rudnicki, Michael A.
中科院分区：
文献类型：
--
作者：
Parise, Gianni;Mckinnell, Iain W.;Rudnicki, Michael A.
骨骼肌卫星细胞在肌肉再生和运动适应中发挥着重要作用。近年来，在骨骼肌中发现了非典型肌源性祖细胞（非卫星细胞肌肉干细胞），并假设其在肌肉再生过程中发挥重要作用。然而，目前尚不清楚除卫星细胞之外的任何细胞群是否在运动引起的损伤后的修复和适应中发挥重要作用。我们评估了卫星细胞群和 CD45(+):Sca-1(+) 细胞群的反应，先前显示这些细胞群在野生型小鼠进行急性偏心偏向运动后支持心脏毒素诱导损伤后的肌肉再生。我们使用电子显微镜、苏木精-伊红染色和单纤维分析观察了运动方案后局部肌肉损伤和修复的证据。此外，我们观察到 48 小时内表达 Myf5 的细胞数量增加了约六倍，并且在运动后至少 96 小时之前仍保持升高状态。然而，我们没有观察到CD45(+):Sca-1(+)细胞群的任何显着扩增或常驻CD45(+):Sca-1(+)细胞向肌源性谱系的定向。此外，先前与CD45(+):Sca-1(+)细胞的肌源性特化相关的Wnt基因家族成员的表达在运动后没有变化。因此，我们得出结论，肌肉卫星细胞是运动引起的应激的主要反应者，并且CD45(+):Sca-1(+)肌源性祖细胞对运动后的肌肉修复/适应没有贡献。
Skeletal muscle satellite cells play an essential role in muscle regeneration and exercise adaptation. In recent years atypical myogenic progenitors (non-satellite-cell muscle stem cells) have been identified in skeletal muscle and have been hypothesized to play an important role in the process of muscle regeneration. It remains unknown, however, whether any populations other than satellite cells play a significant role in repair and adaptation following exercise-induced damage. We assessed the response of the satellite cell population and the CD45(+):Sca-1(+) cell population, previously shown to support muscle regeneration following cardiotoxin-induced injury, after acute eccentrically biased exercise in wild-type mice. We observed evidence of focal muscle damage and repair following the exercise protocol using electron microscopy, hematoxylin-eosin staining, and single-fiber analysis. In addition, we observed an approximately sixfold increase in the number of Myf5-expressing cells by 48 h, which remained elevated until at least 96 h following exercise. We did not, however, observe any significant expansion of the CD45(+):Sca-1(+) cell population or commitment of resident CD45(+):Sca-1(+) cells to the myogenic lineage. Furthermore, expression of Wnt gene family members, previously associated with myogenic specification of CD45(+):Sca-1(+) cells, did not differ following exercise. Therefore, we conclude that muscle satellite cells are the primary responders to exercise-induced stress and that the CD45(+):Sca-1(+) myogenic progenitors do not contribute to muscle repair/adaptation following exercise.