Final answer:
Repeated loading and unloading of tissue affect the mechanical stress response in cells, leading to fluidization, reassembly, and reorganization of the cytoskeleton. Cell and tissue mechanics are central to understanding tissue injury and repair, as well as the impact of aging. Cellular adjustments are crucial for maintaining tissue integrity and function.
Step-by-step explanation:
Repeated loading and unloading of tissue can have significant mechanical effects on cells within that tissue. The dynamical response of cells to this mechanical stress is characterized by cellular adjustments in the cytoskeleton. This process includes an initial fluidization of the stress fibers followed by reassembly and reorganization. These cellular responses can also be seen in the way tissue behaves on larger scales. During continuous or cyclic loading, the tissue tends to undergo a series of responses: an elastic response initially, followed by viscoelastic and potentially plastic changes over time.
On a shorter timescale, the cytoskeleton can undergo immediate fluidization due to the mechanical stress, which can be followed by a phase of reassembly and rigidification. For instance, in response to repeated stretch/Un stretch cycles, it is observed that stress fibers tend to realign in a direction perpendicular to the stretching force. This kind of response is crucial in understanding tissue injury and repair, as well as the impact of aging on tissue integrity and function.
Overall, tissue mechanics is a complex interplay of cellular structure, biochemical signaling, and mechanical forces. These interactions are essential for the maintenance of tissue structure and function, as well as for the response to injury and the process of aging.