We have previously shown that in mouse embryonic fibroblasts, particles located in a cell's lamellar region probe a stiffer environment than that of the perinuclear region, suggesting that lamellar particles are entangled in an actin network higher in density compared to that of the perinuclear region.
Stiffness is not evenly distributed within tissue, and they show that fibroblasts move towards a stiffer environment.
In a stiffer environment, the fibroblasts will transdifferentiate and start to express αSMA and secrete ECM proteins.
In this unfortunate event, CMs in the vicinity of the scar tissue sense a stiffer environment, compared to the healthy adult heart (Jacot et al., 2010).
Interestingly, recent results show that cells can increase force production in response to a stiffer environment [ 13] and that cells are actively mechanoresponsive [ 33], suggesting that an external mechanical cue may be sufficient to initiate net contraction.
It creates a vicious cycle wherein an already stiff environment attracts and activates fibroblasts.
"Everybody arrived with their sleeping bags on Friday night," she says, "which was turmoil, and then they managed to extend the conference into the Oxford Union, an extraordinarily stiff environment that was meant to produce male orators who would become prime ministers.
HIF-1 increases PLOD2 expression during hypoxia, which increases collagen content and impacts the extracellular matrix by increasing cell adhesion, elongation, and motility, creating a stiff cellular environment [ 33].
Guidelines are provided for the design of the wrist compliancy while employing the switching control strategy, such that stable tracking of a motion force reference trajectory can be achieved and bouncing of the manipulator against the stiff environment can be avoided.
