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Mechanotransduction, also referred to as mechano-signal transduction, is a biophysical process wherein cells perceive and respond to mechanical stimuli by converting them into biochemical signals that initiate specific cellular responses. This mechanism is fundamental to the development and growth, and proper functioning of mechanically active tissues, such as the diaphragm—a respiratory muscle vital for breathing in mammals. In vivo, the diaphragm is subjected to transdiaphragmatic pressure, and therefore, its muscle fibers are subjected to mechanical forces not only in the direction of the muscle fibers but also in the direction transverse to the fibers. Previous research conducted in our laboratory uncovered that stretching the diaphragm in either the longitudinal or transverse direction activates distinct mechanotransduction pathways. This indicates that signaling pathways in the diaphragm muscle are regulated in an anisotropic manner. In this review paper, we discussed the underlying mechanisms that regulate the anisotropic signaling pathways in the diaphragmatic muscle, emphasizing the mechanical role of cytoskeletal proteins in this context. Furthermore, we explored the regulatory mechanisms governing mechanosensitive gene transcription, including microRNAs (mechanomiRs), within the diaphragm muscle. Finally, we examined potential links between anisotropic signaling in the diaphragm muscle and various skeletal muscle disorders.
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Anisotropic mechanosensitive pathways in the diaphragm and their implications in muscular dystrophies
The diaphragm is the "respiratory pump;" the muscle that generates pressure to allow ventilation. Diaphragm muscles play a vital function and thus are subjected to continuous mechanical loading. One of its peculiarities is the ability to generate distinct mechanical and biochemical responses depending on the direction through which the mechanical forces applied to it. Contractile forces originated from its contractile components are transmitted to other structural components of its muscle fibers and the surrounding connective tissue. The anisotropic mechanical properties of the diaphragm are translated into biochemical signals that are directionally mechanosensitive by mechanisms that appear to be unique to this muscle. Here, we reviewed the current state of knowledge on the biochemical pathways regulated by mechanical signals emphasizing their anisotropic behavior in the normal diaphragm and analyzed how they are affected in muscular dystrophies.
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- Award ID(s):
- 1714478
- PAR ID:
- 10048882
- Date Published:
- Journal Name:
- Journal of Muscle Research and Cell Motility
- ISSN:
- 0142-4319
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1007/s10974-017-9483-7
