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Acute venous occlusion enhances matrix metalloprotease activity: Implications on endothelial dysfunction
Tom Alsaigh1, Elizabeth S Pocock, John J Bergan
1Department of Bioengineering, The Institute for Engineering in Medicine, University of California San Diego, La Jolla, CA 92093-0412, USA.
Microvascular Research
|October 7, 2010
Summary
Venous hypertension increases enzymatic activity, potentially causing inflammation and endothelial dysfunction by altering critical surface receptors like vascular endothelial growth factor receptor-2 (VEGFR2). This impacts microvascular health.
Area of Science:
- Vascular Biology
- Biochemistry
- Pathophysiology
Background:
- Venous hypertension is linked to microvascular inflammation and endothelial dysfunction.
- The precise cellular and molecular mechanisms driving these changes are not fully understood.
Purpose of the Study:
- To investigate if elevated venous pressure and reduced shear stress increase enzymatic activity.
- To determine if this enzymatic activity affects endothelial surface receptors and leads to dysfunction.
Main Methods:
- A rodent model of acute venular occlusion was used to induce venous hypertension.
- Microzymography and immunohistochemistry were employed to detect enzyme activity and label receptors.
Main Results:
- Increased activity of matrix metalloproteases (MMPs) -1, -8, -9 and tissue inhibitors of metalloproteases (TIMPs) -1, -2 was observed.
- Elevated venous pressure affected vascular endothelial growth factor receptor-2 (VEGFR2) expression, with varied outcomes.
- MMP inhibition suggested possible receptor cleavage by activated enzymes.
Conclusions:
- Elevated venous pressure enhances enzymatic activity.
- This enzymatic activity may contribute to inflammation and endothelial dysfunction in venous hypertension by modulating key surface receptors.
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