Biomedical Sciences, University of Kansas Medical Center, Kansas City, KS, 66160, USA.
Department of Kinesiology, California State University, Northridge, CA, 91330-8287, USA.
Eur J Appl Physiol. 2019 Feb;119(2):333-349. doi: 10.1007/s00421-018-04061-x. Epub 2019 Jan 5.
The plasticity of skeletal muscle, whether an increase in size, change in metabolism, or alteration in structural properties, is in a continuous state of flux largely dependent upon physical activity. Much of the past research has expounded upon these ever-changing aspects of the muscle fiber following exercise. Specifically, endocrine and paracrine signaling have been heavily investigated lending to much of the past literature comprised of such endocrinological dynamics following muscle activity. Mechanotransduction, the ability of a cell to convert a mechanical stimulus into an intracellular biochemical response, has garnered much less attention. Recent work, however, has demonstrated the physical continuity of the muscle fiber, specifically demonstrating a continuous physical link between the extracellular matrix (ECM), cytoskeleton, and nuclear matrix as a means to rapidly regulate gene expression following a mechanical stimulus. Similarly, research has shown mechanical stimuli to directly influence cytoplasmic signaling whether through oxidative adaptations, increased muscle size, or enhanced muscle integrity. Regrettably, minimal research has investigated the role that exercise may play within the mechanotransducing signaling cascades. This proposed line of study may prove paramount as muscle-related diseases greatly impact one's ability to lead an independent lifestyle along with contributing a substantial burden upon the economy. Thus, this review explores both biophysical and biochemical mechanotransduction, and how these signaling pathways may be influenced following exercise.
骨骼肌的可塑性，无论是大小的增加、代谢的改变还是结构特性的改变，都处于一种持续的流动状态，在很大程度上依赖于身体活动。过去的许多研究都阐述了运动后肌肉纤维不断变化的这些方面。具体来说，内分泌和旁分泌信号转导受到了广泛的研究，这使得过去的许多文献都包含了肌肉活动后的这种内分泌动力学。机械转导，即细胞将机械刺激转化为细胞内生化反应的能力，受到的关注较少。然而，最近的工作表明，肌肉纤维具有物理连续性，具体表现为细胞外基质（ECM）、细胞骨架和核基质之间存在连续的物理联系，这是一种在机械刺激后快速调节基因表达的方式。同样，研究表明机械刺激可以直接影响细胞质信号转导，无论是通过氧化适应、增加肌肉大小还是增强肌肉完整性。遗憾的是，很少有研究调查运动在机械转导信号级联中可能发挥的作用。这条研究路线可能非常重要，因为与肌肉相关的疾病极大地影响了人们独立生活的能力，并给经济带来了巨大负担。因此，本综述探讨了生物物理和生化机械转导，以及运动后这些信号通路如何受到影响。
