Alpha-actinin Determines Adherens Junction Properties In Lung Microvascular Endothelial Cells

Abstract Recent evidence from this laboratory indicated that reduced expression of caveolin-1 accompanied the diminished expression of tight junction (TJ)–associated proteins occludin and zonula occludens-1 (ZO-1) following stimulation of brain microvascular endothelial cells (BMECs) with the chemokine CCL2 (formerly called MCP-1). Because attenuated caveolin-1 levels have also been correlated with heightened permeability of other endothelia, the objective of this study was to test the hypothesis that reduced caveolin-1 expression is causally linked to the action of CCL2 on BMEC junctional protein expression and barrier integrity. This was achieved using adenovirus to nondestructively deliver caveolin-1 siRNA (Ad-siCav-1) to BMEC monolayers, which model the blood-brain barrier (BBB). Treatment with siRNA reduced the caveolin-1 protein level as well as occludin and ZO-1. Additionally, occludin exhibited dissociation from the cytoskeletal framework. These changes were attended by comparable alterations in adherens junction (AJ)–associated proteins, VE-cadherin and β-catenin, increased BMEC paracellular permeability, and facilitated the ability of CCL2 to stimulate monocytic transendothelial migration. Furthermore, treating BMECs with cavtratin, a synthetic cell-permeable peptide encoding the caveolin-1 scaffolding domain, antagonized effects of both Ad-siCav-1 and CCL2. These results collectively highlight caveolin-1 loss as a critical step in CCL2-induced modulation of BMEC junctional protein expression and integrity, and possibly serve a crucial role in regulating inflammation at the BBB.

Download Full-text

Cell−Cell Junctions of Dermal Microvascular Endothelial Cells Contain Tight and Adherens Junction Proteins in Spatial Proximity†

Biochemistry ◽

10.1021/bi035517c ◽

2004 ◽

Vol 43 (18) ◽

pp. 5360-5369 ◽

Cited By ~ 31

Author(s):

Claas Rüffer ◽

Anke Strey ◽

Annette Janning ◽

Kwang Sik Kim ◽

Volker Gerke

Keyword(s):

Endothelial Cells ◽

Adherens Junction ◽

Cell Junctions ◽

Spatial Proximity ◽

Microvascular Endothelial Cells ◽

Microvascular Endothelial ◽

Adherens Junction Proteins ◽

Junction Proteins ◽

Cell Cell

Download Full-text

Resveratrol Reduces Matrix Metalloproteinase-2 Activity Induced by Oxygen-Glucose Deprivation and Reoxygenation in Human Cerebral Microvascular Endothelial Cells

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000119 ◽

2012 ◽

Vol 82 (4) ◽

pp. 267-274 ◽

Cited By ~ 5

Author(s):

Zahide Cavdar ◽

Mehtap Y. Egrilmez ◽

Zekiye S. Altun ◽

Nur Arslan ◽

Nilgun Yener ◽

...

Keyword(s):

Endothelial Cells ◽

Neuroprotective Effect ◽

Ischemia Reperfusion ◽

Neurovascular Unit ◽

Glucose Deprivation ◽

Matrix Metalloproteinase 2 ◽

Microvascular Endothelial Cells ◽

Oxygen Glucose Deprivation ◽

Microvascular Endothelial

The main pathophysiology in cerebral ischemia is the structural alteration in the neurovascular unit, coinciding with neurovascular matrix degradation. Among the human matrix metalloproteinases (MMPs), MMP-2 and -9, known as gelatinases, are the key enzymes for degrading type IV collagen, which is the major component of the basal membrane that surrounds the cerebral blood vessel. In the present study, we investigated the effects of resveratrol on cytotoxicity, reactive oxygen species (ROS), and gelatinases (MMP-2 and -9) in human cerebral microvascular endothelial cells exposed to 6 hours of oxygen-glucose deprivation and a subsequent 24 hours of reoxygenation with glucose (OGD/R), to mimic ischemia/reperfusion in vivo. Lactate dehydrogenase increased significantly, in comparison to that in the normoxia group. ROS was markedly increased in the OGD/R group, compared to normoxia. Correspondingly, ROS was significantly reduced with 50 μM of resveratrol. The proMMP-2 activity in the OGD/R group showed a statistically significant increase from the control cells. Resveratrol preconditioning decreased significantly the proMMP-2 in the cells exposed to OGD/R in comparison to that in the OGD/R group. Our results indicate that resveratrol regulates MMP-2 activity induced by OGD/R via its antioxidant effect, implying a possible mechanism related to the neuroprotective effect of resveratrol.

Download Full-text