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Platelet-based Detection of Nitric Oxide in Blood by Measuring VASP Phosphorylation
Published on: January 7, 2019
Vasodilator phosphostimulated protein (VASP) protects endothelial barrier function during hypoxia
Marthe A Schmit1, Valbona Mirakaj, Manfred Stangassinger
1Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Eberhard-Karls University Tübingen, Tübingen, Germany.
Inflammation
|May 25, 2011
Summary
Endothelial vasodilator-stimulated phosphoprotein (VASP) is crucial for maintaining barrier integrity during hypoxia. Its absence exacerbates barrier dysfunction, highlighting VASP
Area of Science:
- Endothelial biology
- Cellular cytoskeleton dynamics
- Hypoxia research
Background:
- The endothelial barrier regulates solute passage via actin cytoskeleton reorganization.
- Vasodilator-stimulated phosphoprotein (VASP) is a key cytoskeletal protein.
- The role of endothelial VASP during hypoxia remains unclear.
Purpose of the Study:
- To investigate the functional role of endothelial VASP during hypoxic conditions.
- To determine the impact of VASP deficiency on endothelial barrier function under hypoxia.
Main Methods:
- Quantification of endothelial VASP expression using Rt-PCR, immunohistochemistry, and Western blot.
- Analysis of VASP promoter activity under hypoxia, including the role of hypoxia-inducible factor 1 alpha.
- Assessment of endothelial barrier permeability in VASP knockout mice and wild-type controls exposed to hypoxia using Evans blue dye extravasation.
Main Results:
- Hypoxia significantly repressed VASP expression in human endothelial cells.
- VASP promoter activity was repressed by hypoxia, dependent on hypoxia-inducible factor 1 alpha binding.
- VASP knockout mice exhibited significantly increased Evans blue extravasation under hypoxia compared to wild-type controls.
Conclusions:
- Endothelial VASP expression is downregulated during hypoxia.
- Endothelial VASP plays a critical role in maintaining endothelial barrier integrity under hypoxic stress.
- Targeting VASP may offer therapeutic potential for conditions involving endothelial barrier dysfunction during hypoxia.
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