Sarcopenia: characteristics, mechanisms and functional significance
Sarcopenia: characteristics, mechanisms and functional significance
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DOI：
10.1093/bmb/ldq008
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发表时间：
2010-09-01
影响因子：
6.7
通讯作者：
Maffulli, Nicola
中科院分区：
文献类型：
--
作者：
Narici, Marco V.;Maffulli, Nicola
肌肉减少症反映了一个渐进的撤回anterior和增加catterior，沿着肌肉再生能力下降。肌肉力量和力量的下降超过肌肉尺寸：老年肌肉本质上是虚弱的。老年人中的肌肉萎缩性肥胖（SO）证实了肌肉质量的损失增加了代谢综合征发展的风险。最近的研究与衰老的肌肉骨骼适应性和关键文件的机制，肌肉萎缩，其功能的影响和SO包括在内。神经性、激素性、免疫性、营养性和身体活动因素导致肌肉减少症。选择性快速纤维萎缩，运动单位的损失和混合纤维的增加是老化的典型结果。卫星细胞数量减少，降低肌肉再生能力。SO促进进一步的肌肉萎缩，并增加代谢综合征发展的风险。快纤维与慢纤维的比例似乎在老年时保持不变。在老年人中，核结构域保持不变。基础蛋白质的合成和分解在老年几乎没有变化。相反，观察到对进食和运动的合成代谢反应以及胰岛素的抗蛋白水解作用减弱。要进一步了解肌肉减少症的机制，就需要将衰老的影响与废用和疾病的影响分开。老年女性对喂养和运动的合成代谢抵抗力更大的原因需要阐明。通过MAPK/notch分子途径激活卫星细胞来增强肌肉再生似乎特别有前途。
Sarcopenia reflects a progressive withdrawal of anabolism and an increased catabolism, along with a reduced muscle regeneration capacity. Muscle force and power decline more than muscle dimensions: older muscle is intrinsically weak. Sarcopenic obesity (SO) among the elderly corroborates to the loss of muscle mass increasing the risk of metabolic syndrome development. Recent studies on the musculoskeletal adaptations with ageing and key papers on the mechanisms of muscle wasting, its functional repercussions and on SO are included. Neuropathic, hormonal, immunological, nutritional and physical activity factors contribute to sarcopenia. Selective fast fibre atrophy, loss of motor units and an increase in hybrid fibres are typical findings of ageing. Satellite cell number decreases reducing muscle regeneration capacity. SO promotes further muscle wasting and increases risk of metabolic syndrome development. The proportion of fast to slow fibres seems maintained in old age. In elderly humans, nuclear domain is maintained constant. Basal protein synthesis and breakdown show little changes in old age. Instead, blunting of the anabolic response to feeding and exercise and of the antiproteolytic effect of insulin is observed. Further understanding of the mechanisms of sarcopenia requires disentangling of the effects of ageing alone from those of disuse and disease. The causes of the greater anabolic resistance to feeding and exercise of elderly women need elucidating. The enhancement of muscle regeneration via satellite cell activation via the MAPK/notch molecular pathways seems particularly promising.