A definition of mechanotransduction might be “the processes whereby cells convert physiological mechanical stimuli into biochemical responses” (Mechanotransduction). This stimuli are roughly happen into three steps:
- (1) mechanocoupling (refers to physical load (often shear or compression))
- (2) cell–cell communication(thousands of cells embedded within an extracellular matrix.
- (3) the effector response.
To simplify this for patients, these same elements can be thought of as
- (1) the mechanical trigger or catalyst,
- (2) the communication throughout a tissue to distribute the loading message
- (3) the response at the cellular level to effect the response that is, the tissue “factory” that produces and assembles the necessary materials in the correct alignment.
The communication at each stage occurs via cell signalling. An information network of messenger proteins, ion channels and lipids.
Cells in the musculoskeltal system are link to a various mechanical forces. Those forces influence a wide spectrum of cellular event; including alterations in cell proliferation (read mere about proliferation on our blog about inflammation), differentialion, gene expression and protein productions.
Mechanotransduction mechanism converts signal into a cascade of cellular and molecular events.
Here you see the cytoskeleton (that is in direct physical communication with the nucleus (ie, tugging the cytoskeleton sends a physical signal to the cell nucleus)) and a top of those you see integrins that flip back and forward every time you move. This is illustrated with the yellow direction. Once the cell nucleus receives the appropriate signals, normal cellular processes are engaged. When this happens, the nucleus signal create mRNA and shuttled to the endoplasmic reticulum in the cell cytoplasm, where it is translated into protein. The protein is secreted and incorporated into extracellular matrix) it creates ribosomes in which starts a serie of intracellular processes leading to matrix remodelling.
What is optimal loading or how do we getting the right loading balance (Ying & Yang) to stimulate tissue healing.? We have to consider the nature, direction, magnitude, intensity, frequency and duration of applied load to affected structures that maximises physiological adaptionen and restore function.