Cisterna Barbara, Giagnacovo Marzia, Costanzo Manuela, Fattoretti Patrizia, Zancanaro Carlo, Pellicciari Carlo, Malatesta Manuela
Department of Neurological and Movement Sciences, Anatomy and Histology Section, University of Verona, Verona, Italy.
Department of Animal Biology, Laboratory of Cell Biology, University of Pavia, Pavia, Italy.
J Anat. 2016 May;228(5):771-83. doi: 10.1111/joa.12429. Epub 2016 Jan 6.
During ageing, a progressive loss of skeletal muscle mass and a decrease in muscle strength and endurance take place, in the condition termed sarcopenia. The mechanisms of sarcopenia are complex and still unclear; however, it is known that muscle atrophy is associated with a decline in the number and/or efficiency of satellite cells, the main contributors to muscle regeneration. Physical exercise proved beneficial in sarcopenia; however, knowledge of the effect of adapted physical exercise on the myogenic properties of satellite cells in aged muscles is limited. In this study the amount and activation state of satellite cells as well as their proliferation and differentiation potential were assessed in situ by morphology, morphometry and immunocytochemistry at light and transmission electron microscopy on 28-month-old mice submitted to adapted aerobic physical exercise on a treadmill. Sedentary age-matched mice served as controls, and sedentary adult mice were used as a reference for an unperturbed control at an age when the capability of muscle regeneration is still high. The effect of physical exercise in aged muscles was further analysed by comparing the myogenic potential of satellite cells isolated from old running and old sedentary mice using an in vitro system that allows observation of the differentiation process under controlled experimental conditions. The results of this ex vivo and in vitro study demonstrated that adapted physical exercise increases the number and activation of satellite cells as well as their capability to differentiate into structurally and functionally correct myotubes (even though the age-related impairment in myotube formation is not fully reversed): this evidence further supports adapted physical exercise as a powerful, non-pharmacological approach to counteract sarcopenia and the age-related deterioration of satellite cell capabilities even at very advanced age.
在衰老过程中，骨骼肌质量会逐渐流失，肌肉力量和耐力会下降，这种情况被称为肌肉减少症。肌肉减少症的机制复杂且尚不清楚；然而，已知肌肉萎缩与卫星细胞数量和/或效率的下降有关，卫星细胞是肌肉再生的主要贡献者。体育锻炼已被证明对肌肉减少症有益；然而，关于适应性体育锻炼对老年肌肉中卫星细胞生肌特性的影响的了解有限。在本研究中，通过形态学、形态测量学和免疫细胞化学方法，在光镜和透射电子显微镜下，对28月龄在跑步机上进行适应性有氧运动的小鼠的卫星细胞数量、激活状态及其增殖和分化潜能进行了原位评估。年龄匹配的久坐不动的小鼠作为对照，久坐不动的成年小鼠作为肌肉再生能力仍然很高的年龄时未受干扰的对照参考。通过使用体外系统比较从老年跑步小鼠和老年久坐小鼠分离的卫星细胞的生肌潜能，进一步分析了体育锻炼对老年肌肉的影响，该体外系统允许在受控实验条件下观察分化过程。这项体外和体内研究的结果表明，适应性体育锻炼增加了卫星细胞的数量和激活，以及它们分化为结构和功能正确的肌管的能力（尽管与年龄相关的肌管形成损伤并未完全逆转）：这一证据进一步支持适应性体育锻炼是一种强大的非药物方法，即使在非常高龄时也能对抗肌肉减少症和与年龄相关的卫星细胞能力衰退。
