运动性骨骼肌适应的分子机制

Molecular Mechanism of Exercise Adaptation in Skeletal Muscles

骨骼肌显著特征是能够对外在活动的变化发生适应。大量运动诱导骨骼肌适应潜在分子机制被提出和进行研究。由收缩到分子事件中产生的机械信号转换过程中能够促使肌细胞适应,其中涉及到第一信使和第二信使上调,从而导致与运动诱导的基因表达和蛋白合成/降解的特异信号通路激活和抑制。大量潜在相关信使被提出,包括机械性牵拉、钙的流动、氧化还原电位和磷酸化势。伴随着第一信号激活,存在于哺乳细胞大量信号通路同样被激活,包括AMPK、钙调蛋白/钙调神经磷酸酶、IGF和NFκB-肿瘤坏死因子-α等信号通路。骨骼肌适应的关键调节分子的发现,能够认识运动诱导骨骼肌特异性的变化,了解这一变化过程,有助于运动训练方法的制订。

Skeletal muscle is capable of remarkable adaptations in response to external altered activities. The mechanism of numerous exercise-induced adaptation in skeletal muscle to potential molecules has been proposed and investigated. The process of converting a mechanical signal generated during contraction to a molecular event that promotes adaptation in a muscle cell involves the up-regulation of primary and secondary messengers that initiates a cascade of events that result in activation and/or repression of specific signaling pathways of exercise-induced gene expression and protein synthesis/degradation. There are numerous putative messengers emerging,including mechanical stretch,calcium flux,redox state and phosphorylation state. Following the initiation of the primary signal, numerous signaling cascades that exist in mammalian cells are activated, such as AMPK,calmodulin/ calcineurin,IGF and NFκB-tumour necrosis factor-α （TNF-α） and other signaling pathways in skeletal muscle. The discovery of key regulators of skeletal muscle adaptation can help to understand the changes of the specificity of exercise-induced skeletal muscle,and understanding this changing process is beneficial to the making-up of the training methods.