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Updated: May 12, 2025
07:42
Live Cell Imaging during Mechanical Stretch
Published on: August 19, 2015
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Mechanobiological mechanism of cyclic stretch-induced cell columnarization
Lun-Wei Lee1, Gang-Hui Lee2, I-Hsiu Su2
1Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan; Department of Physiology, College of Medicine, National Cheng Kung University, Tainan 70101, Taiwan; International Center for Wound Repair and Regeneration, National Cheng Kung University, Tainan 70101, Taiwan.
Cell Reports
|May 8, 2025
Summary
Epithelial cells subjected to cyclic stretch (CS) undergo a shape change to columnarization, driven by actin dynamics and cell junctions. This study reveals the mechanobiology behind this crucial structural adaptation.
Area of Science:
- Cell biology
- Biophysics
- Mechanobiology
Background:
- Epithelial cells must maintain structural integrity under mechanical stress.
- Dynamic mechanical perturbations are common in vivo.
- Understanding cellular responses to mechanical forces is crucial.
Purpose of the Study:
- To investigate the cellular response of epithelial cells to long-term cyclic stretch (CS).
- To elucidate the molecular and biophysical mechanisms underlying CS-induced epithelial cell shape changes, specifically columnarization.
- To identify key factors regulating epithelial cell structural adaptation under mechanical load.
Main Methods:
- Treatment of epithelial cell lines (MDCK, MK4) with long-term cyclic stretch (CS).
- Pharmacological inhibition of focal adhesion kinase (FAK) and disruption of tight junctions/cellular contractility.
- Genetic manipulation (Caveolin-1 overexpression) and vinculin reduction.
- Atomic force microscopy (AFM) to assess apical junctional stiffness.
- Mathematical modeling to analyze cell tension.
Main Results:
- Cyclic stretch induced a transition from cuboidal to columnar shape (columnarization) in MDCK cells, associated with actin accumulation and stress fiber realignment.
- FAK inhibition and reduced vinculin partially inhibited columnarization.
- Disruption of tight junctions or cellular contractility significantly blocked columnarization.
- MK4 cells with weaker junctions showed reduced columnarization, which was rescued by Caveolin-1 overexpression.
- CS and Cav1 overexpression increased apical junctional stiffness.
Conclusions:
- Epithelial cell columnarization under cyclic stretch is a mechanobiological process dependent on actin dynamics, cell-cell junctions, and cellular contractility.
- Apical junctional stiffness and cell tension are key physical parameters regulated by mechanical stimulation.
- This study provides insights into the physical basis of epithelial structural adaptation to mechanical forces.
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