1
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Alonso A, Ebben A, Dabagh M. Impact of disturbed flow and arterial stiffening on mechanotransduction in endothelial cells. Biomech Model Mechanobiol 2023; 22:1919-1933. [PMID: 37709992 DOI: 10.1007/s10237-023-01743-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 07/05/2023] [Indexed: 09/16/2023]
Abstract
Disturbed flow promotes progression of atherosclerosis at particular regions of arteries where the recent studies show the arterial wall becomes stiffer. Objective of this study is to show how mechanotransduction in subcellular organelles of endothelial cells (ECs) will alter with changes in blood flow profiles applied on ECs surface and mechanical properties of arterial wall where ECs are attached to. We will examine the exposure of ECs to atherogenic flow profiles (disturbed flow) and non-atherogenic flow profiles (purely forward flow), while stiffness and viscoelasticity of arterial wall will change. A multicomponent model of endothelial cell monolayer was applied to quantify the response of subcellular organelles to the changes in their microenvironment. Our results show that arterial stiffening alters mechanotransduction in intra/inter-cellular organelles of ECs by slight increase in the transmitted stresses, particularly over central stress fibers (SFs). We also observed that degradation of glycocalyx and exposure to non-atherogenic flow profiles result in significantly higher stresses in subcellular organelles, while degradation of glycocalyx and exposure to atherogenic flow profiles result in dramatically lower stresses in the organelles. Moreover, we show that increasing the arterial wall viscoelasticity leads to slight increase in the stresses transmitted to subcellular organelles. FAs are particularly influenced with the changes in the arterial wall properties and viscoelasticity. Our study suggests that changes in viscoelasticity of arterial wall and degradation state of glycocalyx have to be considered along with arterial stiffening in designing more efficient treatment strategies for atherosclerosis. Our study provides insight into significant role of mechanotransduction in the localization of atherosclerosis by quantifying the role of ECs mechanosensors and suggests that mechanotransduction may play a key role in design of more efficient and precision therapeutics to slow down or block the progression of atherosclerosis.
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Affiliation(s)
- Andrea Alonso
- Department of Biomedical Engineering, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, USA
| | - Alessandra Ebben
- Department of Biomedical Engineering, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, USA
| | - Mahsa Dabagh
- Department of Biomedical Engineering, University of Wisconsin-Milwaukee, Milwaukee, WI, 53211, USA.
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2
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Dessalles CA, Babataheri A, Barakat AI. Pericyte mechanics and mechanobiology. J Cell Sci 2021; 134:134/6/jcs240226. [PMID: 33753399 DOI: 10.1242/jcs.240226] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Pericytes are mural cells of the microvasculature, recognized by their thin processes and protruding cell body. Pericytes wrap around endothelial cells and play a central role in regulating various endothelial functions, including angiogenesis and inflammation. They also serve as a vascular support and regulate blood flow by contraction. Prior reviews have examined pericyte biological functions and biochemical signaling pathways. In this Review, we focus on the role of mechanics and mechanobiology in regulating pericyte function. After an overview of the morphology and structure of pericytes, we describe their interactions with both the basement membrane and endothelial cells. We then turn our attention to biophysical considerations, and describe contractile forces generated by pericytes, mechanical forces exerted on pericytes, and pericyte responses to these forces. Finally, we discuss 2D and 3D engineered in vitro models for studying pericyte mechano-responsiveness and underscore the need for more evolved models that provide improved understanding of pericyte function and dysfunction.
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Affiliation(s)
- Claire A Dessalles
- LadHyX, CNRS, Ecole polytechnique, Institut polytechnique de Paris, 91120, Palaiseau, France
| | - Avin Babataheri
- LadHyX, CNRS, Ecole polytechnique, Institut polytechnique de Paris, 91120, Palaiseau, France
| | - Abdul I Barakat
- LadHyX, CNRS, Ecole polytechnique, Institut polytechnique de Paris, 91120, Palaiseau, France
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3
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Dabagh M, Jalali P, Butler PJ, Randles A, Tarbell JM. Mechanotransmission in endothelial cells subjected to oscillatory and multi-directional shear flow. J R Soc Interface 2018; 14:rsif.2017.0185. [PMID: 28515328 DOI: 10.1098/rsif.2017.0185] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 04/21/2017] [Indexed: 12/27/2022] Open
Abstract
Local haemodynamics are linked to the non-uniform distribution of atherosclerosic lesions in arteries. Low and oscillatory (reversing in the axial flow direction) wall shear stress (WSS) induce inflammatory responses in endothelial cells (ECs) mediating disease localization. The objective of this study is to investigate computationally how the flow direction (reflected in WSS variation on the EC surface over time) influences the forces experienced by structural components of ECs that are believed to play important roles in mechanotransduction. A three-dimensional, multi-scale, multi-component, viscoelastic model of focally adhered ECs is developed, in which oscillatory WSS (reversing or non-reversing) parallel to the principal flow direction, or multi-directional oscillatory WSS with reversing axial and transverse components are applied over the EC surface. The computational model includes the glycocalyx layer, actin cortical layer, nucleus, cytoskeleton, focal adhesions (FAs), stress fibres and adherens junctions (ADJs). We show the distinct effects of atherogenic flow profiles (reversing unidirectional flow and reversing multi-directional flow) on subcellular structures relative to non-atherogenic flow (non-reversing flow). Reversing flow lowers stresses and strains due to viscoelastic effects, and multi-directional flow alters stress on the ADJs perpendicular to the axial flow direction. The simulations predict forces on integrins, ADJ filaments and other substructures in the range that activate mechanotransduction.
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Affiliation(s)
- Mahsa Dabagh
- Department of Biomedical Engineering, Duke University, Durham, NC, USA .,School of Energy Systems, Lappeenranta University of Technology, Lappeenranta, Finland
| | - Payman Jalali
- School of Energy Systems, Lappeenranta University of Technology, Lappeenranta, Finland
| | - Peter J Butler
- Department of Biomedical Engineering, The Pennsylvania State University, Pennsylvania, PA, USA
| | - Amanda Randles
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - John M Tarbell
- Department of Biomedical Engineering, The City College of New York, New York, NY, USA
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4
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Zhao B, Hu M, Wu H, Ren C, Wang J, Cui S. Tenascin-C expression and its associated pathway in BMSCs following co-culture with mechanically stretched ligament fibroblasts. Mol Med Rep 2017; 15:2465-2472. [PMID: 28447748 PMCID: PMC5428738 DOI: 10.3892/mmr.2017.6329] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 01/09/2017] [Indexed: 01/09/2023] Open
Abstract
The occurrence of pelvic organ prolapse (POP) is closely associated with alterations in the extracellular matrix proteins of the supporting ligament. Bone marrow mesenchymal stem cells (BMSCs) have the potential to differentiate into a variety of cell types, including osteoblasts, chondroblasts and adipocytes. Therefore, BMSCs have the potential to improve the clinical outcomes of POP. Tenascin-C is a large glycoprotein that is present in the ECM and is involved in morphogenetic movements, and tissue patterning and repair. The aim of the present study was to investigate the effect of mechanical stretching on tenascin-C expression during the differentiation of BMSCs induced by pelvic ligament fibroblasts. BMSCs were isolated from 7-day-old Sprague Dawley rats. Fibroblasts were obtained from rat pelvic ligaments and, at the fourth passage, were subjected to 10% deformation with 1 Hz, periodic one-way mechanical stretch stimulation, followed by co-culture with BMSCs. The co-culture with stretched fibroblasts increased tenascin-C and transforming growth factor (TGF)-β expression levels, compared with groups without mechanical stimulation. Neutralizing anti-TGF-β1 antibodies, and inhibitors of TGF-β receptor, mitogen-activated protein kinase (MAPK) kinase and MAPK, decreased tenascin-C expression levels induced by TGF-β and mechanical stretching. The results of the present study suggested that the regulation of tenascin-C expression levels in BMSCs co-cultured with mechanically stretched pelvic ligament fibroblasts is mediated via the soluble growth factor TGF-β and the MAPK signaling pathway. In addition, these results indicated that in an indirect co-culture system, pelvic ligament fibroblasts with mechanical stretch stimulation may promote the synthesis of tenascin-C and BMSC differentiation into pelvic ligament fibroblasts.
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Affiliation(s)
- Bing Zhao
- Department of Obstetrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Mengcai Hu
- Department of Obstetrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Huiyan Wu
- Department of Obstetrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Chenchen Ren
- Department of Obstetrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Jianshe Wang
- Department of Clinical Medicine, Hebi Polytechnic College, Hebi, Henan 458030, P.R. China
| | - Shihong Cui
- Department of Obstetrics, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
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5
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Lopez BJ, Valentine MT. Molecular control of stress transmission in the microtubule cytoskeleton. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015. [PMID: 26225932 DOI: 10.1016/j.bbamcr.2015.07.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In this article, we will summarize recent progress in understanding the mechanical origins of rigidity, strength, resiliency and stress transmission in the MT cytoskeleton using reconstituted networks formed from purified components. We focus on the role of network architecture, crosslinker compliance and dynamics, and molecular determinants of single filament elasticity, while highlighting open questions and future directions for this work.
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Affiliation(s)
- Benjamin J Lopez
- Department of Mechanical Engineering and Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-5070, USA
| | - Megan T Valentine
- Department of Mechanical Engineering and Neuroscience Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106-5070, USA.
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6
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Model of cellular mechanotransduction via actin stress fibers. Biomech Model Mechanobiol 2015; 15:331-44. [PMID: 26081725 DOI: 10.1007/s10237-015-0691-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 06/04/2015] [Indexed: 10/24/2022]
Abstract
Mechanical stresses due to blood flow regulate vascular endothelial cell structure and function and play a key role in arterial physiology and pathology. In particular, the development of atherosclerosis has been shown to correlate with regions of disturbed blood flow where endothelial cells are round and have a randomly organized cytoskeleton. Thus, deciphering the relation between the mechanical environment, cell structure, and cell function is a key step toward understanding the early development of atherosclerosis. Recent experiments have demonstrated very rapid (∼100 ms) and long-distance (∼10 μm) cellular mechanotransduction in which prestressed actin stress fibers play a critical role. Here, we develop a model of mechanical signal transmission within a cell by describing strains in a network of prestressed viscoelastic stress fibers following the application of a force to the cell surface. We find force transmission dynamics that are consistent with experimental results. We also show that the extent of stress fiber alignment and the direction of the applied force relative to this alignment are key determinants of the efficiency of mechanical signal transmission. These results are consistent with the link observed experimentally between cytoskeletal organization, mechanical stress, and cellular responsiveness to stress. Based on these results, we suggest that mechanical strain of actin stress fibers under force constitutes a key link in the mechanotransduction chain.
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7
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Zhao C, Yu J, Peng R, Rao M, Hu M. Biodegradable dendritic copolymers consisting of poly(L-lactide) and cRGDfK peptide: synthesis, characterization, and regulation of MC3T3-E1 cell functions. Des Monomers Polym 2015. [DOI: 10.1080/15685551.2015.1041088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- Changhong Zhao
- Department of Pharmacy, Tongren Polytechnic College, Education Park of Tongren, Tongren 554300, China
| | - Jiansheng Yu
- Department of Pharmacy, Tongren Polytechnic College, Education Park of Tongren, Tongren 554300, China
| | - Renhui Peng
- Department of Pharmacy, Tongren Polytechnic College, Education Park of Tongren, Tongren 554300, China
| | - Maoyang Rao
- Department of Pharmacy, Tongren Polytechnic College, Education Park of Tongren, Tongren 554300, China
| | - Meizhong Hu
- Department of Pharmacy, Tongren Polytechnic College, Education Park of Tongren, Tongren 554300, China
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8
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Abstract
The sense of touch informs us of the physical properties of our surroundings and is a critical aspect of communication. Before touches are perceived, mechanical signals are transmitted quickly and reliably from the skin's surface to mechano-electrical transduction channels embedded within specialized sensory neurons. We are just beginning to understand how soft tissues participate in force transmission and how they are deformed. Here, we review empirical and theoretical studies of single molecules and molecular ensembles thought to be involved in mechanotransmission and apply the concepts emerging from this work to the sense of touch. We focus on the nematode Caenorhabditis elegans as a well-studied model for touch sensation in which mechanics can be studied on the molecular, cellular, and systems level. Finally, we conclude that force transmission is an emergent property of macromolecular cellular structures that mutually stabilize one another.
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Affiliation(s)
- Michael Krieg
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Alex Dunn
- Department of Chemical Engineering, Stanford University School of Engineering, Stanford, CA, USA
| | - Miriam B. Goodman
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
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9
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Dabagh M, Jalali P, Butler PJ, Tarbell JM. Shear-induced force transmission in a multicomponent, multicell model of the endothelium. J R Soc Interface 2015; 11:20140431. [PMID: 24966239 DOI: 10.1098/rsif.2014.0431] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Haemodynamic forces applied at the apical surface of vascular endothelial cells (ECs) provide the mechanical signals at intracellular organelles and through the inter-connected cellular network. The objective of this study is to quantify the intracellular and intercellular stresses in a confluent vascular EC monolayer. A novel three-dimensional, multiscale and multicomponent model of focally adhered ECs is developed to account for the role of potential mechanosensors (glycocalyx layer, actin cortical layer, nucleus, cytoskeleton, focal adhesions (FAs) and adherens junctions (ADJs)) in mechanotransmission and EC deformation. The overriding issue addressed is the stress amplification in these regions, which may play a role in subcellular localization of mechanotransmission. The model predicts that the stresses are amplified 250-600-fold over apical values at ADJs and 175-200-fold at FAs for ECs exposed to a mean shear stress of 10 dyne cm(-2). Estimates of forces per molecule in the cell attachment points to the external cellular matrix and cell-cell adhesion points are of the order of 8 pN at FAs and as high as 3 pN at ADJs, suggesting that direct force-induced mechanotransmission by single molecules is possible in both. The maximum deformation of an EC in the monolayer is calculated as 400 nm in response to a mean shear stress of 1 Pa applied over the EC surface which is in accord with measurements. The model also predicts that the magnitude of the cell-cell junction inclination angle is independent of the cytoskeleton and glycocalyx. The inclination angle of the cell-cell junction is calculated to be 6.6° in an EC monolayer, which is somewhat below the measured value (9.9°) reported previously for ECs subjected to 1.6 Pa shear stress for 30 min. The present model is able, for the first time, to cross the boundaries between different length scales in order to provide a global view of potential locations of mechanotransmission.
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Affiliation(s)
- Mahsa Dabagh
- School of Technology, Lappeenranta University of Technology, Lappeenranta, Finland
| | - Payman Jalali
- School of Technology, Lappeenranta University of Technology, Lappeenranta, Finland
| | - Peter J Butler
- Department of Biomedical Engineering, The Pennsylvania State University, Pennsylvania, PA, USA
| | - John M Tarbell
- Department of Biomedical Engineering, The City College of New York, New York, USA
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Ingber DE, Wang N, Stamenović D. Tensegrity, cellular biophysics, and the mechanics of living systems. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2014; 77:046603. [PMID: 24695087 PMCID: PMC4112545 DOI: 10.1088/0034-4885/77/4/046603] [Citation(s) in RCA: 227] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The recent convergence between physics and biology has led many physicists to enter the fields of cell and developmental biology. One of the most exciting areas of interest has been the emerging field of mechanobiology that centers on how cells control their mechanical properties, and how physical forces regulate cellular biochemical responses, a process that is known as mechanotransduction. In this article, we review the central role that tensegrity (tensional integrity) architecture, which depends on tensile prestress for its mechanical stability, plays in biology. We describe how tensional prestress is a critical governor of cell mechanics and function, and how use of tensegrity by cells contributes to mechanotransduction. Theoretical tensegrity models are also described that predict both quantitative and qualitative behaviors of living cells, and these theoretical descriptions are placed in context of other physical models of the cell. In addition, we describe how tensegrity is used at multiple size scales in the hierarchy of life—from individual molecules to whole living organisms—to both stabilize three-dimensional form and to channel forces from the macroscale to the nanoscale, thereby facilitating mechanochemical conversion at the molecular level.
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Affiliation(s)
- Donald E. Ingber
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Harvard Medical School, Harvard School of Engineering and Applied Sciences, and Boston Children’s Hospital, 3 Blackfan Circle, CLSB5, Boston, MA 02115
| | - Ning Wang
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 W. Green St, Urbana, IL 61801
| | - Dimitrije Stamenović
- Department of Biomedical Engineering, and Division of Material Science and Engineering, College of Engineering, Boston University, 44 Cummington Mall, Boston, MA 02215
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Krieg M, Dunn AR, Goodman MB. Mechanical control of the sense of touch by β-spectrin. Nat Cell Biol 2014; 16:224-33. [PMID: 24561618 PMCID: PMC4046587 DOI: 10.1038/ncb2915] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Accepted: 01/10/2014] [Indexed: 01/20/2023]
Abstract
The ability to sense and respond to mechanical stimuli emanates from sensory neurons and is shared by most, if not all, animals. Exactly how such neurons receive and distribute mechanical signals during touch sensation remains mysterious. Here, we show that sensation of mechanical forces depends on a continuous, pre-stressed spectrin cytoskeleton inside neurons. Mutations in the tetramerization domain of Caenorhabditis elegans β-spectrin (UNC-70), an actin-membrane crosslinker, cause defects in sensory neuron morphology under compressive stress in moving animals. Through atomic force spectroscopy experiments on isolated neurons, in vivo laser axotomy and fluorescence resonance energy transfer imaging to measure force across single cells and molecules, we show that spectrin is held under constitutive tension in living animals, which contributes to elevated pre-stress in touch receptor neurons. Genetic manipulations that decrease such spectrin-dependent tension also selectively impair touch sensation, suggesting that such pre-tension is essential for efficient responses to external mechanical stimuli.
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Affiliation(s)
- Michael Krieg
- Department of Molecular & Cellular Physiology, Stanford University, USA
- Department of Chemical Engineering, Stanford University, USA
| | | | - Miriam B. Goodman
- Department of Molecular & Cellular Physiology, Stanford University, USA
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12
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Chang CW, Kumar S. Vinculin tension distributions of individual stress fibers within cell-matrix adhesions. J Cell Sci 2013; 126:3021-30. [PMID: 23687380 DOI: 10.1242/jcs.119032] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Actomyosin stress fibers (SFs) enable cells to exert traction on planar extracellular matrices (ECMs) by tensing focal adhesions (FAs) at the cell-ECM interface. Although it is widely appreciated that the spatial and temporal distribution of these tensile forces play key roles in polarity, motility, fate choice, and other defining cell behaviors, virtually nothing is known about how an individual SF quantitatively contributes to tensile loads borne by specific molecules within associated FAs. We address this key open question by using femtosecond laser ablation to sever single SFs in cells while tracking tension across vinculin using a molecular optical sensor. We show that disruption of a single SF reduces tension across vinculin in FAs located throughout the cell, with enriched vinculin tension reduction in FAs oriented parallel to the targeted SF. Remarkably, however, some subpopulations of FAs exhibit enhanced vinculin tension upon SF irradiation and undergo dramatic, unexpected transitions between tension-enhanced and tension-reduced states. These changes depend strongly on the location of the severed SF, consistent with our earlier finding that different SF pools are regulated by distinct myosin activators. We critically discuss the extent to which these measurements can be interpreted in terms of whole-FA tension and traction and propose a model that relates SF tension to adhesive loads and cell shape stability. These studies represent the most direct and high-resolution intracellular measurements of SF contributions to tension on specific FA proteins to date and offer a new paradigm for investigating regulation of adhesive complexes by cytoskeletal force.
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Affiliation(s)
- Ching-Wei Chang
- Department of Bioengineering, University of California Berkeley, Berkeley, CA 94720, USA
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13
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Hwang Y, Gouget CLM, Barakat AI. Mechanisms of cytoskeleton-mediated mechanical signal transmission in cells. Commun Integr Biol 2013; 5:538-42. [PMID: 23336020 PMCID: PMC3541317 DOI: 10.4161/cib.21633] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Recent experiments have demonstrated very rapid long-distance transmission of mechanical forces within cells. Because the speed of this transmission greatly exceeds that of reaction-diffusion signaling, it has been conjectured that it occurs via the propagation of elastic waves through the actin stress fiber network. To explore the plausibility of this conjecture, we recently developed a model of small amplitude stress fiber deformations in prestressed viscoelastic stress fibers subjected to external forces. The model results demonstrated that rapid mechanical signal transmission is only possible when the external force is applied orthogonal to the stress fiber axis and that the dynamics of this transmission are governed by a balance between the prestress in the stress fiber and the stress fiber's material viscosity. The present study, which is a follow-up on our previous model, uses dimensional analysis to: (1) further evaluate the plausibility of the elastic wave conjecture and (2) obtain insight into mechanical signal transmission dynamics in simple stress fiber networks. We show that the elastic wave scenario is likely not the mechanism of rapid mechanical signal transmission in actin stress fibers due to the highly viscoelastic character of these fibers. Our analysis also demonstrates that the time constant characterizing mechanical stimulus transmission is strongly dependent on the topology of the stress fiber network, implying that network organization plays an important role in determining the dynamics of cellular responsiveness to mechanical stimulation.
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Affiliation(s)
- Yongyun Hwang
- Hydrodynamics Laboratory (LadHyX); Ecole Polytechnique; CNRS UMR7646; Palaiseau, France
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