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Updated: Jun 16, 2026
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Human Saphenous Vein Endothelial Cell Isolation and Exposure to Controlled Levels of Shear Stress and Stretch
Published on: April 21, 2023
Stretch and Shear Interactions Affect Intercellular Junction Protein Expression and Turnover in Endothelial Cells.
Danielle E Berardi1, John M Tarbell
1Department of Bioengineering, Pennsylvania State University, University Park, PA 16802.
Cellular and Molecular Bioengineering
|February 18, 2010
Summary
Atherosclerosis development is linked to hemodynamic forces. Specific stress phase angles (SPA) influence endothelial cell junctions, affecting disease susceptibility.
Area of Science:
- Cardiovascular Biology
- Biomedical Engineering
- Cellular Mechanotransduction
Background:
- Atherosclerosis development is influenced by complex hemodynamics.
- Endothelial cells (ECs) are directly affected by hemodynamic forces like wall shear stress (WSS) and circumferential stress/strain (CS).
- These forces can alter intercellular junctions, impacting vascular health.
Purpose of the Study:
- To investigate the combined effects of WSS and CS on endothelial cell junctions.
- To emphasize the role of the stress phase angle (SPA), the temporal phase difference between WSS and CS.
- To correlate SPA with atherosclerosis susceptibility in specific arterial regions.
Main Methods:
- Utilized a hemodynamic simulator to apply combined WSS and CS to endothelial cells.
- Analyzed the expression of the tight junction protein zonula occludens-1.
- Quantified endothelial cell apoptosis rates.
- Varied the stress phase angle (SPA) to simulate atheroprotective (0°) and atherogenic (-180°) conditions.
Main Results:
- At 5 hours, significantly higher zonula occludens-1 expression was observed for SPA = 0° (atheroprotective) compared to SPA = -180° (atherogenic).
- Apoptosis rates were significantly higher for SPA = -180° than for SPA = 0°.
- Atherogenic SPA = -180° correlated with decreased tight junction protein and increased apoptosis, suggesting reduced junctional stability.
Conclusions:
- The stress phase angle (SPA) significantly impacts endothelial cell junctional stability and permeability.
- Atherogenic SPA values (-180°) promote leaky junctions, increasing susceptibility to atherogenic macromolecule infiltration.
- Findings highlight SPA as a critical factor in the hemodynamic localization of atherosclerosis.
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