Orientation Response of Stress Fibers in Cultured Cells under Biaxial Cyclic Stretch: Hypothesis and Theoretical Prediction

2000 ◽  
pp. 273-282
Author(s):  
Hiroshi Yamada ◽  
Tohru Takemasa ◽  
Takami Yamaguchi
Keyword(s):  
Theoretical Prediction ◽  
Cultured Cells ◽  
Cyclic Stretch ◽  
Stress Fibers ◽  
Orientation Response

Relationship Between Orientation Angle in Intracellular Stress Fibers and Range of Uniaxial Cyclic Stretch

2000 ◽  
Author(s):  
Hiroshi Yamada ◽  
Tohru Takemasa ◽  
Takami Yamaguchi
Keyword(s):  
Endothelial Cells ◽  
Cultured Cells ◽  
Umbilical Vein ◽  
Orientation Angle ◽  
Mechanical Stimulus ◽  
Cyclic Stretch ◽  
Stress Fibers ◽  
Experimental Result ◽  
Silicone Membrane ◽  
Umbilical Vein Endothelial Cells

Abstract We hypothesized an avoidance of deformation and a limit of sensitivity of cell response to the mechanical stimulus for the orientation of stress fibers in cultured cells on a silicone membrane which was subjected to a uniaxial cyclic stretch. We compared the theoretical prediction with the experimental result of stress fibers in the human umbilical vein endothelial cells under various ranges of uniaxial cyclic stretch (Takemasa et al. 1998). The results showed that the proposed hypothesis predicted the orientation of stress fibers under various ranges of cyclic stretch well.

scholarly journals Mechano-chemical control of human endothelium orientation and size.

1989 ◽  
Vol 109 (1) ◽  
pp. 331-339 ◽  
Author(s):  
V P Shirinsky ◽  
A S Antonov ◽  
K G Birukov ◽  
A V Sobolevsky ◽  
Y A Romanov ◽  
...  
Keyword(s):  
Adenylate Cyclase ◽  
Umbilical Vein ◽  
Giant Cells ◽  
Stress Fiber ◽  
Fiber Formation ◽  
Cyclic Stretch ◽  
Stress Fibers ◽  
Conventional Culture ◽  
Orientation Response ◽  
Umbilical Vein Endothelial Cells

Human umbilical vein endothelial cells (EC) were grown on elastic silicone membranes subjected to cyclic stretch, simulating arterial wall motion. Stretching conditions (20% amplitude, 52 cycle/min) stimulated stress fiber formation and their orientation transversely to the strain direction. Cell bodies aligned along the same axis after the actin cytoskeleton. EC orientation response was inhibited by the adenylate cyclase activator, forskolin (10(-5) M), which caused stress fiber disassembly and the redistribution of F-actin to the cortical cytoplasm. Preoriented EC depleted of stress fibers by forskolin treatment retained their aligned state. Thus, stress fibers are essential for the process of EC orientation induced by repeated strain, but not for the maintenance of EC orientation. The monolayer formed by EC grown to confluence in conditions of intermittent strain consisted of uniform elongated cells and was resistant to deformation. In contrast, the monolayer assembled in stationary conditions was less compliant and exposed local denudations on initiation of stretching. When stretched in the presence of 10(-5) M forskolin it rapidly (3-4 h) reestablished integrity but gained a heterogeneous appearance since denuded areas were covered by giant cells. The protective effect of forskolin was because of the stimulation of EC spreading. This feature of forskolin was demonstrated while studying its action on EC spreading and repair of a scratched EC monolayer in conventional culture. Thus mechanical deformation and adenylate cyclase activity may be important factors in the control of endothelium morphology in human arteries.

Mechanically Optimized Orientation of Intracellular Stress Fibers Under Cyclic Stretch

2000 ◽  
Author(s):  
Hiroshi Yamada ◽  
Tohru Takemasa ◽  
Takami Yamaguchi
Keyword(s):  
Endothelial Cell ◽  
Continuum Mechanics ◽  
Cellular Response ◽  
Length Change ◽  
Mechanical Stimulus ◽  
Stress Fiber ◽  
Cyclic Stretch ◽  
Stress Fibers ◽  
Biological Phenomenon ◽  
The Continuum

Abstract To elucidate the orientation of stress fibers in a cultured endothelial cell under cyclic stretch, we hypothesized that a stress fiber aligns so as to minimize the summation of its length change under cyclic stretch, and that there is a limit in the sensitivity of cellular response to the mechanical stimulus. Results from numerical simulations based on the continuum mechanics describe the experimental observations under uniaxial stretch well. They give us an insight to the biological phenomenon of the orientation in stress fibers under biaxial stretch from the viewpoint of mechanical engineering.

Mechanosensitive myosin II but not cofilin primarily contributes to cyclic cell stretch-induced selective disassembly of actin stress fibers

2021 ◽  
Author(s):  
Wenjing Huang ◽  
Tsubasa S. Matsui ◽  
Takumi Saito ◽  
Masahiro Kuragano ◽  
Masayuki Takahashi ◽  
...  
Keyword(s):  
Cellular Response ◽  
Early Stage ◽  
Myosin Ii ◽  
Cyclic Stretch ◽  
Stress Fibers ◽  
Lim Kinase ◽  
Lim Kinase 1 ◽  
Chronic Activation ◽  
Selective Disassembly ◽  
Actin Stress Fibers

Cells adapt to applied cyclic stretch (CS) to circumvent chronic activation of proinflammatory signaling. Currently, the molecular mechanism of the selective disassembly of actin stress fibers (SFs) in the stretch direction, which occurs at the early stage of the cellular response to CS, remains controversial. Here we suggest that the mechanosensitive behavior of myosin II, a major cross-linker of SFs, primarily contributes to the directional disassembly of the actomyosin complex SFs in bovine vascular smooth muscle cells and human U2OS osteosarcoma cells. First, we identified that CS with a shortening phase that exceeds in speed the inherent contractile rate of individual SFs leads to the disassembly. To understand the biological basis, we investigated the effect of expressing myosin regulatory light chain mutants and found that SFs with less actomyosin activities disassemble more promptly upon CS. We consequently created a minimal mathematical model that recapitulates the salient features of the direction-selective and threshold-triggered disassembly of SFs to show that disassembly or, more specifically, unbundling of the actomyosin bundle SFs is enhanced with sufficiently fast cell shortening. We further demonstrated that similar disassembly of SFs is inducible in the presence of an active LIM-kinase-1 mutant that deactivates cofilin, suggesting that cofilin is dispensable as opposed to a previously proposed mechanism.

Strain waveform dependence of stress fiber reorientation in cyclically stretched osteoblastic cells: effects of viscoelastic compression of stress fibers

2012 ◽  
Vol 302 (10) ◽  
pp. C1469-C1478 ◽  
Author(s):  
Kazuaki Nagayama ◽  
Yuki Kimura ◽  
Narutaka Makino ◽  
Takeo Matsumoto
Keyword(s):  
Stress Relaxation ◽  
Hold Time ◽  
Significant Negative Correlation ◽  
In Situ Stress ◽  
Cyclic Stretch ◽  
Stress Fibers ◽  
Osteoblastic Cells ◽  
Normal Strain ◽  
Holding Period ◽  
Cyclic Stretching

Actin stress fibers (SFs) of cells cultured on cyclically stretched substrate tend to reorient in the direction in which a normal strain of substrate becomes zero. However, little is known about the mechanism of this reorientation. Here we investigated the effects of cyclic stretch waveform on SF reorientation in osteoblastic cells. Cells adhering to silicone membranes were subjected to cyclic uniaxial stretch, having one of the following waveforms with an amplitude of 8% for 24 h: triangular, trapezoid, bottom hold, or peak hold. SF reorientation of these cells was then analyzed. No preferential orientation was observed for the triangular and the peak-hold waveforms, whereas SFs aligned mostly in the direction with zero normal strain (∼55°) with other waveforms, especially the trapezoid waveform, which had a hold time both at loaded and unloaded states. Viscoelastic properties of SFs were estimated in a quasi-in situ stress relaxation test using intact and SF-disrupted cells that maintained their shape on the substrate. The dynamics of tension FSFsacting on SFs during cyclic stretching were simulated using these properties. The simulation demonstrated that FSFsdecreased gradually during cyclic stretching and exhibited a compressive value (FSFs< 0). The magnitude and duration time of the compressive forces were relatively larger in the group with a trapezoid waveform. The frequency of SF orientation had a significant negative correlation with the applied compressive forces integrated with time in a strain cycle, and the integrated value was largest with the trapezoid waveform. These results may indicate that the applied compressive forces on SFs have a significant effect on the stretch-induced reorientation of SFs, and that SFs realigned to avoid their compression. Stress relaxation of SFs might be facilitated during the holding period in the trapezoid waveform, and depolymerization and reorientation of SFs were significantly accelerated by their viscoelastic compression.

scholarly journals Microinjection of nonmuscle and smooth muscle caldesmon into fibroblasts and muscle cells.

1990 ◽  
Vol 111 (6) ◽  
pp. 2487-2498 ◽  
Author(s):  
Y Yamakita ◽  
S Yamashiro ◽  
F Matsumura
Keyword(s):  
Smooth Muscle ◽  
Molecular Mass ◽  
Cultured Cells ◽  
Muscle Cells ◽  
Biochemical Properties ◽  
Stress Fibers ◽  
Relative Molecular Mass ◽  
Short Period ◽  
Nonmuscle Cells ◽  
Mass Form

Caldesmon is present in a high molecular mass form in smooth muscle and predominantly in a low molecular mass form in nonmuscle cells. Their biochemical properties are very similar. To examine whether these two forms of caldesmon behave differently in cultured cells, we microinjected fluorescently labeled smooth muscle and nonmuscle caldesmons into fibroblasts. Simultaneous injection of both caldesmons into the same cells has revealed that both high and low relative molecular mass caldesmons are quickly (within 10 min) and stably (over 3 d) incorporated into the same structures of microfilaments including stress fibers and membrane ruffles, suggesting that nonmuscle cells do not distinguish nonmuscle caldesmon from smooth muscle caldesmon. The effect of calmodulin on the incorporation of caldesmon has been examined by coinjection of caldesmon with calmodulin. We have found that calmodulin retards the incorporation of caldesmon into stress fibers for a short period (10 min) but not for a longer incubation (30 min). The behavior of caldesmon in developing muscle cells was also examined because we previously observed that caldesmon disappears during myogenesis (Yamashiro, S., R. Ishikawa, and F. Matsumura. 1988. Protoplasma Suppl. 2: 9-21). We have found that, in contrast to its stable incorporation into stress fibers of fibroblasts, caldesmon is unable to be incorporated into thin filament structure (I-band) of differentiated muscle.

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