New Insights into the Molecular Mechanisms of Vascular Permeability in Diabetes

2002 ◽  
pp. 23-33
Author(s):  
David A. Antonetti ◽  
Keyword(s):  
Vascular Permeability ◽  
Molecular Mechanisms

scholarly journals Revealing the role of phospholipase Cβ3 in the regulation of VEGF-induced vascular permeability

Blood ◽  
2012 ◽  
Vol 120 (11) ◽  
pp. 2167-2173 ◽  
Author(s):  
Luke H. Hoeppner ◽  
Kathryn N. Phoenix ◽  
Karl J. Clark ◽  
Resham Bhattacharya ◽  
Xun Gong ◽  
...  
Keyword(s):  
Vascular Permeability ◽  
Real Time ◽  
Molecular Mechanisms ◽  
Negative Regulator ◽  
Transgenic Zebrafish ◽  
Genetic Studies ◽  
In Vivo Models ◽  
Ischemic Diseases

AbstractVEGF induces vascular permeability (VP) in ischemic diseases and cancer, leading to many pathophysiological consequences. The molecular mechanisms by which VEGF acts to induce hyperpermeability are poorly understood and in vivo models that easily facilitate real-time, genetic studies of VP do not exist. In the present study, we report a heat-inducible VEGF transgenic zebrafish (Danio rerio) model through which VP can be monitored in real time. Using this approach with morpholino-mediated gene knock-down and knockout mice, we describe a novel role of phospholipase Cβ3 as a negative regulator of VEGF-mediated VP by regulating intracellular Ca2+ release. Our results suggest an important effect of PLCβ3 on VP and provide a new model with which to identify genetic regulators of VP crucial to several disease processes.

Pirfenidone exhibits cardioprotective effects by regulating myocardial fibrosis and vascular permeability in pressure-overloaded hearts

2015 ◽  
Vol 309 (3) ◽  
pp. H512-H522 ◽  
Author(s):  
Kiyoshi Yamagami ◽  
Toru Oka ◽  
Qi Wang ◽  
Takamaru Ishizu ◽  
Jong-Kook Lee ◽  
...  
Keyword(s):  
Heart Failure ◽  
Endothelial Cells ◽  
Vascular Permeability ◽  
Molecular Mechanisms ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Chronic Phase ◽  
Vehicle Group

Although cardiac fibrosis causes heart failure, its molecular mechanisms remain elusive. In this study, we investigated the mechanisms of cardiac fibrosis and examined the effects of the antifibrotic drug pirfenidone (PFD) on chronic heart failure. To understand the responsible mechanisms, we generated an in vivo pressure-overloaded heart failure model via transverse aortic constriction (TAC) and examined the effects of PFD on chronic-phase cardiac fibrosis and function. In the vehicle group, contractile dysfunction and left ventricle fibrosis progressed further from 4 to 8 wk after TAC but were prevented by PFD treatment beginning 4 wk after TAC. We isolated cardiac fibroblasts and vascular endothelial cells from the left ventricles of adult male mice and investigated the cell-type-specific effects of PFD. Transforming growth factor-β induced upregulated collagen 1 expression via p38 phosphorylation and downregulated claudin 5 (Cldn5) expression in cardiac fibroblasts and endothelial cells, respectively; both processes were inhibited by PFD. Moreover, PFD inhibited changes in the collagen 1 and Cldn5 expression levels, resulting in reduced fibrosis and serum albumin leakage into the interstitial space during the chronic phase in TAC hearts. In conclusion, PFD inhibited cardiac fibrosis by suppressing both collagen expression and the increased vascular permeability induced by pressure overload.

scholarly journals Renal microvascular damaged in diabetes mellitus with hyperlipidemia through the regulation of MAMs by PACS2 in endothelial cell

2021 ◽  
Author(s):  
Zhihao Shu ◽  
Shuhua Chen ◽  
Hong Xiang ◽  
Ruoru Wu ◽  
Shaoli Zhao ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Endothelial Cells ◽  
Fatty Acid ◽  
Endothelial Cell ◽  
Mouse Model ◽  
Vascular Permeability ◽  
High Fat Diet ◽  
Molecular Mechanisms ◽  
Kidney Tissue ◽  
High Fat

Abstract Background: The prevalence of diabetic vascular complications is rapidly increasing, especially in the diabetes mellitus with hyperlipidemia. Consistent hyperglycemia and hyperlipidemia impairs microvascular, but lack of effective intervention target to prevention or reduced the risk of serious bad ending. Methods: A mouse model of diabetes combined with hyperlipidemia were established by STZ injection and high fat diet to observe the possible damage of HGHF to renal blood vessels include vascular permeability, fibrosis and subcellular structure. Then, we replicated an in vitro endothelial cell injury model treated by 30mm Glucose and 0.1mm palmitic acid to verify its main functional changes. Proteomics and metabolomics were used to explore the molecular mechanisms behind diabetic microvascular damage. The mechanisms were further verified at siRNA interference and transgenic knockout mice. Results: We found that renal vascular permeability impaired and fibrosis increased significantly in the stz+HFD mice. In human umbilical vein endothelial cells (HUVECs) treated with high glucose/high fat (HGHF), the number of mitochondrial-associated membranes (MAMs) and the expression of phosphofurin acidic cluster sorting protein 2 (PACS2) increased. In particular, gene manipulation of PACS2 altered endothelial cell MAMs. Knocking down PACS2 restored the barrier function of HUVECs. In vivo, knocking out PACS2 ameliorated the kidney injury in diabetic mice induced by streptozotocin and fed with high-fat diet for up to 20 weeks. PACS2-/- mice leaked less vascular Evan’s blue and improved glomerular fibrosis in the kidney tissue of hyperglycemia and hyperlipidemia mouse model. We further observed the reduction of fatty acid β-oxidation (FAO), CPT1α expression, and NADPH production in endothelial cells induced by HGHF. These changes in fatty acid metabolism were rescued by silencing PACS2, but were blocked by the FAO inhibitor, etomoxir. Conclusion: PACS2 impacts the metabolic response of endothelial cells to HGHF through MAMs. Loss of PACS2 expression reduces glomerular endothelial cells barrier injury, induced by VE-Cadherin internalized under HGHF. PACS2 play a metabolism and MAMs regulators in the vascular endothelial cells of diabetes with hyperlipidemia.

scholarly journals Role of Endothelial G Protein-Coupled Receptor Kinase 2 in Angioedema

Hypertension ◽  
2020 ◽  
Vol 76 (5) ◽  
pp. 1625-1636 ◽  
Author(s):  
Jessica Gambardella ◽  
Daniela Sorriento ◽  
Maria Bova ◽  
Mariarosaria Rusciano ◽  
Stefania Loffredo ◽  
...  
Keyword(s):  
Vascular Permeability ◽  
G Protein ◽  
Molecular Mechanisms ◽  
No Production ◽  
Receptor Kinase ◽  
Severe Phenotype ◽  
G Protein Coupled Receptor ◽  
G Protein Coupled

Excessive BK (bradykinin) stimulation is responsible for the exaggerated permeabilization of the endothelium in angioedema. However, the molecular mechanisms underlying these responses have not been investigated. BK receptors are Gq-protein-coupled receptors phosphorylated by GRK2 (G protein-coupled receptor kinase 2) with a hitherto unknown biological and pathophysiological significance. In the present study, we sought to identify the functional role of GRK2 in angioedema through the regulation of BK signaling. We found that the accumulation of cytosolic Ca 2+ in endothelial cells induced by BK was sensitive to GRK2 activity, as it was significantly augmented by inhibiting the kinase. Accordingly, permeabilization and NO production induced by BK were enhanced, as well. In vivo, mice with reduced GRK2 levels in the endothelium (Tie2-CRE/GRK2 fl+/fl − ) exhibited an increased response to BK in terms of vascular permeability and extravasation. Finally, patients with reduced GRK2 levels displayed a severe phenotype of angioedema. Taken together, these findings establish GRK2 as a novel pivotal regulator of BK signaling with an essential role in the pathophysiology of vascular permeability and angioedema.

Effect of ischemia and reperfusion without airway occlusion on vascular barrier function in the in vivo mouse lung

2003 ◽  
Vol 95 (5) ◽  
pp. 1971-1978 ◽  
Author(s):  
Jeffrey M. Dodd-o ◽  
Maria L. Hristopoulos ◽  
Nauder Faraday ◽  
David B. Pearse
Keyword(s):  
Lung Injury ◽  
Vascular Permeability ◽  
Barrier Function ◽  
Molecular Mechanisms ◽  
Ischemia Reperfusion ◽  
Left Lung ◽  
Pulmonary Vascular Permeability ◽  
Ischemic Time ◽  
Airway Occlusion

Ischemia-reperfusion (I/R) lung injury causes increased vascular permeability and edema. We developed an in vivo murine model of I/R allowing measurement of pulmonary vascular barrier function without airway occlusion. The left pulmonary artery (PA) was occluded with an exteriorized, slipknotted suture in anesthetized C57BL/6J mice. The effect of ischemic time was determined by subjecting mice to 5, 10, or 30 min of left lung ischemia followed by 150 min of reperfusion. The effect of reperfusion time was determined by subjecting mice to 30 min of left lung ischemia followed by 30 or 150 min of reperfusion. Changes in pulmonary vascular barrier function were measured with the Evans blue dye (EBD) technique, dual-isotope radiolabeled albumin (RA), bronchoalveolar lavage (BAL) protein concentration, and wet weight-to-dry weight ratio (WW/DW). Increasing left lung ischemia with constant reperfusion time or increasing left lung reperfusion time after constant ischemic time resulted in significant increases in left lung EBD content at all times compared with both right lung values and sham surgery mice. The effects of left lung ischemia on lung EBD were corroborated by RA but the effects of increasing reperfusion time differed, suggesting binding of EBD to lung tissue. An increase in WW/DW was only detected after 30 min of reperfusion, suggesting edema clearance. BAL protein concentrations were unaffected. We conclude that short periods of I/R, without airway occlusion, increase pulmonary vascular permeability in the in vivo mouse, providing a useful model to study molecular mechanisms of I/R lung injury.

Tumors: Wounds That Do Not Heal—A Historical Perspective with a Focus on the Fundamental Roles of Increased Vascular Permeability and Clotting

2019 ◽  
Vol 45 (06) ◽  
pp. 576-592 ◽  
Author(s):  
Harold F. Dvorak
Keyword(s):  
Connective Tissue ◽  
Vascular Permeability ◽  
Tumor Cells ◽  
Molecular Mechanisms ◽  
Degradation Products ◽  
Inflammatory Diseases ◽  
Tumor Stroma ◽  
Inflammatory Cells ◽  
Fibrin Gel ◽  
Normal Tissues

AbstractSimilarities between solid tumor stroma generation, wound healing, chronic inflammation, and associated inflammatory diseases have prompted interest from the time of Virchow. However, it was not until the 1970s that these entities were shown to share important molecular mechanisms. Foundational to all of them is the initiating role of vascular endothelial growth factor (VEGF-A) in increasing vascular permeability to plasma and plasma proteins. Extravasated plasma activates the tissue factor clotting pathway, leading to extravascular deposition of a fibrin gel. Fibrin serves initially as a provisional stroma that provides a favorable substrate for the attachment and migration of tumor cells, as well as host fibroblasts, endothelial, and inflammatory cells. Fibrin and its degradation products have proangiogenic activity with important roles in the generation of new blood vessels and connective tissue stroma. Over time, fibrin is degraded and replaced by vascular and subsequently by dense, relatively avascular collagenous connective tissue, the end-product referred to as desmoplasia in tumors and scar in healed wounds. Fibrin and the mature stroma that replaces it provide a diffusion barrier to chemotherapy and a structural barrier that inflammatory cells must cross to reach tumor cells. Plasma solutes of varying size cross the endothelial cells lining capillaries and venules of normal tissues and “mother” vessels of tumors and wounds by different anatomical pathways. VEGF-A levels fall back to normal as wounds heal but remain perpetually elevated in solid tumors. Thus, tumors may heal centrally but continually initiate new healing activity as they grow and invade surrounding normal tissues.

scholarly journals JAM-A Acts via C/EBP-α to Promote Claudin-5 Expression and Enhance Endothelial Barrier Function

2020 ◽  
Vol 127 (8) ◽  
pp. 1056-1073 ◽  
Author(s):  
Nikolaos Kakogiannos ◽  
Laura Ferrari ◽  
Costanza Giampietro ◽  
Anna Agata Scalise ◽  
Claudio Maderna ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Vascular Permeability ◽  
Tight Junctions ◽  
Barrier Function ◽  
Molecular Mechanisms ◽  
Endothelial Permeability ◽  
Endothelial Barrier ◽  
Endothelial Barrier Function ◽  
Barrier Dysfunction ◽  
Factor C

Rationale: Intercellular tight junctions are crucial for correct regulation of the endothelial barrier. Their composition and integrity are affected in pathological contexts, such as inflammation and tumor growth. JAM-A (junctional adhesion molecule A) is a transmembrane component of tight junctions with a role in maintenance of endothelial barrier function, although how this is accomplished remains elusive. Objective: We aimed to understand the molecular mechanisms through which JAM-A expression regulates tight junction organization to control endothelial permeability, with potential implications under pathological conditions. Methods and Results: Genetic deletion of JAM-A in mice significantly increased vascular permeability. This was associated with significantly decreased expression of claudin-5 in the vasculature of various tissues, including brain and lung. We observed that C/EBP-α (CCAAT/enhancer-binding protein-α) can act as a transcription factor to trigger the expression of claudin-5 downstream of JAM-A, to thus enhance vascular barrier function. Accordingly, gain-of-function for C/EBP-α increased claudin-5 expression and decreased endothelial permeability, as measured by the passage of fluorescein isothiocyanate (FITC)-dextran through endothelial monolayers. Conversely, C/EBP-α loss-of-function showed the opposite effects of decreased claudin-5 levels and increased endothelial permeability. Mechanistically, JAM-A promoted C/EBP-α expression through suppression of β-catenin transcriptional activity, and also through activation of EPAC (exchange protein directly activated by cAMP). C/EBP-α then directly binds the promoter of claudin-5 to thereby promote its transcription. Finally, JAM-A–C/EBP-α–mediated regulation of claudin-5 was lost in blood vessels from tissue biopsies from patients with glioblastoma and ovarian cancer. Conclusions: We describe here a novel role for the transcription factor C/EBP-α that is positively modulated by JAM-A, a component of tight junctions that acts through EPAC to up-regulate the expression of claudin-5, to thus decrease endothelial permeability. Overall, these data unravel a regulatory molecular pathway through which tight junctions limit vascular permeability. This will help in the identification of further therapeutic targets for diseases associated with endothelial barrier dysfunction. Graphic Abstract: An graphic abstract is available for this article.

Molecular Mechanisms of Vascular Permeability in Diabetic Retinopathy

1999 ◽  
Vol 14 (4) ◽  
pp. 240-248 ◽  
Author(s):  
David A. Antonetti ◽  
Erich Lieth ◽  
Alistair J. Barber ◽  
Thomas W. Gardner
Keyword(s):  
Diabetic Retinopathy ◽  
Vascular Permeability ◽  
Molecular Mechanisms
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