Related Experiment Video
Updated: Aug 6, 2026
16:46
A Novel Stretching Platform for Applications in Cell and Tissue Mechanobiology
Published on: June 3, 2014
Moderately Reduced Contractility Decreases Epithelial Cell-Cell Contact Rupture Under Large External Stretch
S Sharmin1, C Obermeyer1, V Maruthamuthu1
1Department of Mechanical & Aerospace Engineering, Old Dominion University, Norfolk, VA.
Biorxiv : the Preprint Server for Biology
|July 17, 2026
Summary
Moderate inhibition of cell contractility preserves epithelial barrier integrity under mechanical stretch by reducing internal forces and increasing tissue compliance. This protects cell-cell contacts from ruptures during strain.
Area of Science:
- Biophysics
- Cell Biology
- Tissue Engineering
Background:
- Epithelial sheets require robust barrier function during mechanical stress.
- The interplay between actomyosin contractility and external strain on epithelial integrity is not fully understood.
Purpose of the Study:
- To investigate the biophysical trade-offs between actomyosin contractility and epithelial barrier resilience under mechanical stretch.
- To determine how moderate inhibition of contractility affects epithelial cell-cell contact integrity during large deformations.
Main Methods:
- Utilized Madin-Darby Canine Kidney (MDCK) cell islands.
- Applied a custom-built biaxial stretching device for 38% linear stretch.
- Employed non-muscle myosin II inhibitor (blebbistatin), traction force microscopy, and nanoindentation.
Main Results:
- A moderate concentration (10 μM) of blebbistatin maintained cell-cell contact integrity and protected against stretch-induced ruptures.
- Traction force microscopy showed over 60% reduction in cell-generated strain energy.
- Nanoindentation revealed a >40% decrease in cellular Young's modulus.
Conclusions:
- Moderate contractility inhibition safeguards epithelial junctions by reducing active tensile stress and passive elastic forces during stretch.
- This shift towards a more compliant, relaxed state preserves barrier integrity under severe mechanical challenge.
- The findings suggest a general biophysical mechanism for maintaining epithelial function during mechanical stress.
Related Concept Videos
01:13Cell-matrix's Response to Mechanical Forces
In animal cells, the extracellular matrix allows cells within tissues to withstand external stresses and transmits signals from the outside of the cell to the inside. The extracellular matrix is extensive, and its composition varies between different types of tissues. For example, the reticular fibers and ground substance make up the ECM in loose connective tissue, while collagen and bone minerals make up the ECM of bone tissue.
Anchoring junctions mechanically attach a cell to the...
Anchoring junctions mechanically attach a cell to the...
01:26Tension Response at Adherens Junctions
The adherens junctions that anchor cells together are multi-protein complexes that dynamically adapt to mechanical stimuli such as tensile forces and shear stress. Mechanosensory proteins in these junctions can sense such mechanical stimuli and undergo a shift in their conformation, resulting in an altered function — a process called mechanotransduction.
α-Catenin as a Mechanosensory Protein
The α-catenin of adherens junctions is an allosteric protein with three VH (vinculin homology) domains...
α-Catenin as a Mechanosensory Protein
The α-catenin of adherens junctions is an allosteric protein with three VH (vinculin homology) domains...
01:16Cell Motility through Blebbing
Blebs are a type of membrane protrusion formed by the internal hydrostatic pressure of the cytoplasm. Blebs are observed in several cell types, including fibroblasts, immune cells, and single-celled organisms like the amoeba. The primary function of blebs is cell locomotion and apoptosis, but they are also found during necrosis and cell division. The life cycle of a bleb comprises an initiation phase followed by the expansion and retraction phases.
Blebbing Through the Matrix
In multicellular...
Blebbing Through the Matrix
In multicellular...
01:25Smooth Muscle Contraction
Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
01:10The Role of Actin and Myosin in Non-muscle Cells
Actin and myosin or actomyosin filaments also play a significant role in cells other than those involved in muscle contraction (which occurs within the sarcomere of muscle cells). The mechanism of non-muscle cell contractile bundles was first observed in Dictyostelium and Acanthamoeba. In non-muscle cells, two bundles are commonly found: stress fibers and actomyosin adherence belts. These contractile bundles are smaller and less organized than the ones found in muscle cells. They are held...
01:15Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.