Mechanical factors influence β-catenin localization and barrier properties

Area of Science:

• Vascular biology
• Cellular mechanobiology
• Biophysics

Background:

• Mechanical forces critically regulate vascular homeostasis by modulating endothelial cell behavior.
• Adherens junctions are key sites for mechanotransduction in endothelial cells, with β-catenin playing a crucial role.
• The precise mechanisms by which endothelial cells sense and respond to mechanical stimuli, particularly concerning β-catenin signaling, remain incompletely understood.

Purpose of the Study:

• To investigate the impact of substrate topography, wall shear stress, and cyclic stretch on adherens junction dynamics.
• To analyze the regulation of β-catenin localization by these mechanical cues.
• To link these mechanobiological responses to the control of endothelial monolayer permeability.

Main Methods:

• Utilized a custom-developed flow chamber and bioreactor system.
• Applied well-defined wall shear stress and gradients of strain to mature human endothelial cells.
• Quantified endothelial cell responses, including β-catenin localization and barrier properties, under varying mechanical conditions and surface topographies.

Main Results:

• Demonstrated that substrate topography, wall shear stress, and cyclic stretch significantly influence adherens junction dynamics and β-catenin localization in endothelial cells.
• Showed that these mechanical stimuli modulate endothelial barrier properties, affecting monolayer permeability.
• Provided evidence for context-dependent mechanoregulation of β-catenin signaling.

Conclusions:

• Mechanical forces, including shear stress, strain, and topography, are potent regulators of endothelial cell adherens junctions and barrier function.
• β-catenin localization and signaling are key mediators of endothelial responses to mechanical stimuli.
• Understanding these mechanotransduction pathways is crucial for maintaining vascular homeostasis and potentially treating vascular diseases.