scholarly journals Vascular Permeability in Cerebral Cavernous Malformations

2015 ◽  
Vol 35 (10) ◽  
pp. 1632-1639 ◽  
Author(s):  
Abdul G Mikati ◽  
Omaditya Khanna ◽  
Lingjiao Zhang ◽  
Romuald Girard ◽  
Robert Shenkar ◽  
...  
Keyword(s):  
Disease Activity ◽  
Vascular Permeability ◽  
Human Subjects ◽  
Endothelial Permeability ◽  
Perfusion Magnetic Resonance Imaging ◽  
Cerebral Cavernous Malformations ◽  
Cavernous Malformations ◽  
Familial Form

Patients with the familial form of cerebral cavernous malformations (CCMs) are haploinsufficient for the CCM1, CCM2, or CCM3 gene. Loss of corresponding CCM proteins increases RhoA kinase-mediated endothelial permeability in vitro, and in mouse brains in vivo. A prospective case-controlled observational study investigated whether the brains of human subjects with familial CCM show vascular hyperpermeability by dynamic contrast-enhanced quantitative perfusion magnetic resonance imaging, in comparison with CCM cases without familial disease, and whether lesional or brain vascular permeability correlates with CCM disease activity. Permeability in white matter far (WMF) from lesions was significantly greater in familial than in sporadic cases, but was similar in CCM lesions. Permeability in WMF increased with age in sporadic patients, but not in familial cases. Patients with more aggressive familial CCM disease had greater WMF permeability compared to those with milder disease phenotype, but similar lesion permeability. Subjects receiving statin medications for routine cardiovascular indications had a trend of lower WMF, but not lesion, permeability. This is the first demonstration of brain vascular hyperpermeability in humans with an autosomal dominant disease, as predicted mechanistically. Brain permeability, more than lesion permeability, may serve as a biomarker of CCM disease activity, and help calibrate potential drug therapy.

scholarly journals The cerebral cavernous malformation proteins CCM2L and CCM2 prevent the activation of the MAP kinase MEKK3

2015 ◽  
Vol 112 (46) ◽  
pp. 14284-14289 ◽  
Author(s):  
Xavier Cullere ◽  
Eva Plovie ◽  
Paul M. Bennett ◽  
Calum A. MacRae ◽  
Tanya N. Mayadas
Keyword(s):  
Endothelial Cells ◽  
Cavernous Malformation ◽  
Body Axis ◽  
Cerebral Cavernous Malformations ◽  
Loss Of Function ◽  
Cavernous Malformations ◽  
Downstream Target ◽  
Density Flow

Three genes, CCM1, CCM2, and CCM3, interact genetically and biochemically and are mutated in cerebral cavernous malformations (CCM). A recently described member of this CCM family of proteins, CCM2-like (CCM2L), has high homology to CCM2. Here we show that its relative expression in different tissues differs from that of CCM2 and, unlike CCM2, the expression of CCM2L in endothelial cells is regulated by density, flow, and statins. In vitro, both CCM2L and CCM2 bind MEKK3 in a complex with CCM1. Both CCM2L and CCM2 interfere with MEKK3 activation and its ability to phosphorylate MEK5, a downstream target. The in vivo relevance of this regulation was investigated in zebrafish. A knockdown of ccm2l and ccm2 in zebrafish leads to a more severe “big heart” and circulation defects compared with loss of function of ccm2 alone, and also leads to substantial body axis abnormalities. Silencing of mekk3 rescues the big heart and body axis phenotype, suggesting cross-talk between the CCM proteins and MEKK3 in vivo. In endothelial cells, CCM2 deletion leads to activation of ERK5 and a transcriptional program that are downstream of MEKK3. These findings suggest that CCM2L and CCM2 cooperate to regulate the activity of MEKK3.

scholarly journals The Adaptor Protein Nck1, but not Nck2, Mediates Shear Stress-Induced Endothelial Permeability

2019 ◽  
Author(s):  
Mabruka Alfaidi ◽  
Umesh Bhattarai ◽  
Elizabeth D Cockerham ◽  
A.W. Orr
Keyword(s):  
Shear Stress ◽  
Vascular Permeability ◽  
Pore Formation ◽  
Critical Role ◽  
Endothelial Permeability ◽  
Adaptor Protein ◽  
Adaptor Proteins ◽  
Disturbed Flow

AbstractAlteration in hemodynamic shear stress at atheroprone sites promotes endothelial paracellular pore formation and permeability. Previously, we have reported that a peptide inhibitor to Nck prevented shear stress-induced p21 activated kinase (PAK) activation and endothelial permeability. However, the specificity of this peptide is unclear, and the role of individual Nck isoforms remain unknown. Here, we show that genetic deletion of Nck1/2 adaptor proteins significantly ameliorates shear stress induced permeability, and selective isoform depletion suggests distinct signaling mechanisms. Only Nck1 deletion significantly reduces flow-induced paracellular pore formation and permeability, whereas Nck2 depletion has no significant effects. Additionally, Nck1 reexpression, but not Nck2, restores shear stress-induced permeability in Nck1/2 knockout cells, confirming the non-compensating roles. In vivo, using the partial carotid ligation model of disturbed flow, Nck1 knockout prevented the increase in vascular permeability, as assessed by both Evans blue extravasation and leakage of plasma fibrinogen into the vessel wall. Domain swap experiments mixing SH2 (phosphotyrosine binding) and SH3 (proline rich binding) domains between Nck1 and Nck2 showed a dispensable role for SH2 domains but a critical role for the Nck1 SH3 domains in rescuing shear stress-induced endothelial permeability. Consistent with this, both Nck1 and Nck2 bind to PECAM-1 (SH2 dependent) in response to shear stress, but only Nck1 ablation interferes with shear stress-induced PAK2 activation (SH3 dependent). This work provides the first evidence that Nck1 and Nck2 play distinct roles in flow-induced vascular permeability.New and NoteworthyThe present study shows a specific role for Nck1 in endothelial permeability in response to shear stress. Using in vitro and in vivo models, we demonstrate improvement in endothelial barrier integrity in cells subjected to disturbed flow only following Nck1 but not Nck2 deletion. Selective Nck1 inhibition may limit endothelial permeability at sites of disturbed flow to reduce atherosclerosis without affecting angiogenesis, which requires both Nck1 and Nck2 inhibition.

scholarly journals Berberine Exerts a Protective Effect on Gut-Vascular Barrier via the Modulation of the Wnt/Beta-Catenin Signaling Pathway During Sepsis

2018 ◽  
Vol 49 (4) ◽  
pp. 1342-1351 ◽  
Author(s):  
Yan He ◽  
Xiaoming Yuan ◽  
Hao Zuo ◽  
Ying Sun ◽  
Aiwen Feng
Keyword(s):  
Protective Effect ◽  
Vascular Permeability ◽  
Signaling Pathway ◽  
Cecal Ligation ◽  
Endothelial Permeability ◽  
Bacterial Invasion ◽  
Beta Catenin ◽  
Endotoxin Level

Background/Aims: The gut-vascular barrier (GVB) has recently been depicted to dampen the bacterial invasion of the bloodstream. The intestinal mucosa is a tissue rich in small vessels including capillaries. In this study, the protective effect of berberine on GVB in small bowel mucosa was investigated. Methods: The rat cecal ligation and puncture (CLP) sepsis model was employed to evaluate the effect of berberine on serum endotoxin level and intestinal vascular permeability to Evans blue in vivo. The rat intestinal microvascular endothelial cells (RIMECs) treated by lipopolysaccharide (LPS) were used to assess the effect of berberine on endothelial permeability to FITC-labeled dextran, transendothelial electrical resistance (TEER), and tight junction (TJ) and adherens junction (AJ) expression in vitro. Results: After 24-hr CLP operation the serum endotoxin concentration and gut vascular permeability were significantly increased, while berberine markedly reduced endotoxin level and vascular leakage. In vitro, LPS not only dramatically increased endothelial permeability of RIMECs to FITC-dextran, but also decreased TEER and inhibited claudin-12, beta-catenin and VE-cadherin expression. These effects of LPS were antagonized by berberine. In addition, our in vivo and vitro studies also confirmed that the effect of berberine on GVB could be partially abolished by ICG001. Conclusion: Berberine exerted a protective effect on GVB function in sepsis, which was strictly related to the modulation of the Wnt/beta-catenin signaling pathway.

scholarly journals Roles of tumor necrosis factor p55 and p75 receptors in TNF-α-induced vascular permeability

2001 ◽  
Vol 281 (4) ◽  
pp. C1173-C1179 ◽  
Author(s):  
Elisabetta Ferrero ◽  
Maria Raffaella Zocchi ◽  
Elena Magni ◽  
Maria Carla Panzeri ◽  
Flavio Curnis ◽  
...  
Keyword(s):  
Tumor Necrosis Factor ◽  
Vascular Permeability ◽  
Tumor Necrosis ◽  
Endothelial Permeability ◽  
Mitogen Activated Protein Kinase ◽  
Cytoskeletal Reorganization ◽  
Necrosis Factor ◽  
Stimulation Of

We have investigated the role of p55 and p75 tumor necrosis factor receptors 1 and 2 (TNFR1 and TNFR2, respectively) in TNF-induced alteration of endothelial permeability in vitro and in vivo. Stimulation of TNFR1 with an agonist antibody or a receptor-selective TNF mutein increased the flux of125I-albumin through endothelial cell monolayers. An antagonist anti-TNFR1 antibody, but not antagonist anti-TNFR2 antibodies, blocked the activity of TNF in vitro. Stimulation of TNFR1, but not TNFR2, induced cytoskeletal reorganization associated with increased permeability. SB-203580, a p38 mitogen-activated protein kinase inhibitor, blocked TNFR1-induced cytoskeletal reorganization and permeability. A selective mouse TNFR1 agonist and human TNF, which binds to murine TNFR1, increased the leakage of trypan blue-albumin from liver vessels in mice. These results indicate that stimulation of TNFR1 is necessary and sufficient to increase endothelial permeability in vitro and in vivo. However, an antagonist anti-murine TNFR2 antibody partially inhibited the effect of murine TNF on liver vessels, suggesting that TNFR2 also plays a role in the regulation of TNF-induced vascular permeability in vivo.

scholarly journals ANTI-INFLAMMATORY ACTIVITY OF CURCUMIN AND CAPSAICIN AUGMENTED IN COMBINATION

2017 ◽  
Vol 9 (6) ◽  
pp. 145
Author(s):  
Thriveni Vasanth Kumar ◽  
Manjunatha H. ◽  
Rajesh Kp
Keyword(s):  
Acetic Acid ◽  
Protective Effect ◽  
Vascular Permeability ◽  
Diclofenac Sodium ◽  
Significant Inhibition ◽  
Inflammatory Activity ◽  
Anti Inflammatory ◽  
The Individual

Objective: Dietary curcumin and capsaicin are well known for their health beneficial potencies. The current study was done to assess the anti-inflammatory activity of curcumin, capsaicin and their combination by employing in vitro and in vivo models.Methods: We investigated the protective effect of curcumin, capsaicin and their combination using in vitro heat induced human red blood cell (HRBC) membrane stabilisation, in vivo 3% agar induced leukocyte mobilisation and acetic acid induced vascular permeability assay.Results: Curcumin, capsaicin and their combination exhibited concentration dependent protective effect against heat-induced HRBC membrane destabilisation, while combined curcumin and capsaicin restored 87.0±0.64 % membrane stability and it is found to be better than curcumin, capsaicin and diclofenac sodium (75.0±0.25. 72±0.9 and 80.0±0.31 %) protective effect. In agar suspension induced leukocyte mobilization assay, the combined curcumin and capsaicin had shown 39.5±1.58 % of inhibition compared to individual curcumin and capsaicin, which showed moderate inhibition of 16.0±3.14 and 21.6±2.17 % respectively. Besides, the combined curcumin and capsaicin had shown highly significant inhibition of acetic acid-induced vascular permeability in rats (62.0±3.14 %), whereas individual curcumin and capsaicin showed moderate inhibition of vascular permeability with 36.0±2.41 and 43.0±1.92 % respectively.Conclusion: This study demonstrates the significant anti-inflammatory property of combined curcumin and capsaicin at half of the individual concentration of curcumin and capsaicin.

Abstract 73: Bone Morphogenetic Protein Activity Modulates Endothelial Barrier Function

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Thomas Helbing ◽  
Elena Ketterer ◽  
Bianca Engert ◽  
Jennifer Heinke ◽  
Sebastian Grundmann ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Barrier Function ◽  
Endothelial Permeability ◽  
Bmp Signaling ◽  
Endothelial Barrier ◽  
Endothelial Barrier Function

Introduction: Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome, are associated with high morbidity and mortality in patients. During the progression of ALI, the endothelial cell barrier of the pulmonary vasculature becomes compromised, leading to pulmonary edema, a characteristic feature of ALI. It is well-established that EC barrier dysfunction is initiated by cytoskeletal remodeling, which leads to disruption of cell-cell contacts and formation of paracellular gaps, allowing penetration of protein-rich fluid and inflammatory cells. Bone morphogenetic proteins (BMPs) are important players in endothelial dysfunction and inflammation but their effects on endothelial permeability in ALI have not been investigated until now. Methods and Results: As a first approach to assess the role of BMPs in acute lung injury we analysed BMP4 and BMPER expression in an infectious (LPS) and a non-infectious (bleomycin) mouse models of acute lung injury. In both models BMP4 and BMPER protein expression levels were reduced demonstrated by western blots, suggesting that BMPs are involved in progression ALI. To assess the role of BMPs on vascular leakage, a key feature of ALI, BMP activity in mice was inhibited by i.p. administration of LDN193189, a small molecule that blocks BMP signalling. After 3 days Evans blue dye (EVB) was administered i.v. and dye extravasation into the lungs was quantified as a marker for vascular leakage. Interestingly, LDN193189 significantly increased endothelial permeability compared to control lungs, indicating that BMP signaling is involved in maintenance of endothelial barrier function. To quantify effects of BMP inhibition on endothelial barrier function in vitro, HUVECs were seeded onto transwell filters and were exposed to LDN193189. After 3 days FITC-dextrane was added and passage into the lower chamber was quantified as a marker for endothelial barrier function. Thrombin served as a positive control. As expected from our in vivo experiments inhibition of BMP signaling by LDN193189 enhanced FITC-dextrane passage. To study specific effects of BMPs on endothelial barrier function, two protagonist of the BMP family, BMP2 and BMP4, or BMP modulator BMPER were tested in the transwell assay in vitro. Interestingly BMP4 and BMPER, but not BMP2, reduced FITC-dextrane passage demonstrating that BMP4 and BMPER improved endothelial barrier function. Vice versa, specific knock down of BMP4 or BMPER increased leakage in transwell assays. Im immuncytochemistry silencing of BMPER or BMP4 induced hyperpermeability as a consequence of a pro-inflammatory endothelial phenotype characterised by reduced cell-cell contacts and increased actin stress fiber formation. Additionally, the pro-inflammatory endothelial phenotype was confirmed by real-time revealing increased expression of adhesion molecules ICAM-1 or proinflammatory cytokines such as IL-6 and IL-8 in endothelial cells after BMPER or BMP4 knock down. Confirming these in vitro results BMPER +/- mice exhibit increased extravasation of EVB into the lungs, indicating that partial loss of BMPER impairs endothelial barrier function in vitro and in vivo. Conclusion: We identify BMPER and BMP4 as local regulators of vascular permeability. Both are protective for endothelial barrier function and may open new therapeutic avenues in the treatment of acute lung injury.

Clock gene-independent daily regulation of haemoglobin oxidation in red blood cells

2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Human Subjects ◽  
Developmental Regulation ◽  
Physiological Role ◽  
Cell Types ◽  
The Body

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.

scholarly journals Effects of prostaglandin lipid mediators on agonist-induced lung endothelial permeability and inflammation

2017 ◽  
Vol 313 (4) ◽  
pp. L710-L721 ◽  
Author(s):  
Yunbo Ke ◽  
Olga V. Oskolkova ◽  
Nicolene Sarich ◽  
Yufeng Tian ◽  
Albert Sitikov ◽  
...  
Keyword(s):  
Protective Effect ◽  
Vascular Endothelial Cells ◽  
Biological Activities ◽  
Cell Monolayer ◽  
Endothelial Permeability ◽  
In Vivo Model ◽  
Barrier Dysfunction ◽  
Anti Inflammatory

Prostaglandins (PG), the products of cyclooxygenase-mediated conversion of arachidonic acid, become upregulated in many situations including allergic response, inflammation, and injury, and exhibit a variety of biological activities. Previous studies described barrier-enhancing and anti-inflammatory effects of PGE2 and PGI2 on vascular endothelial cells (EC). Yet, the effects of other PG members on EC barrier and inflammatory activation have not been systematically analyzed. This study compared effects of PGE2, PGI2, PGF2α, PGA2, PGJ2, and PGD2 on human pulmonary EC. EC permeability was assessed by measurements of transendothelial electrical resistance and cell monolayer permeability for FITC-labeled tracer. Anti-inflammatory effects of PGs were evaluated by analysis of expression of adhesion molecule ICAM1 and secretion of soluble ICAM1 and cytokines by EC. PGE2, PGI2, and PGA2 exhibited the most potent barrier-enhancing effects and most efficient attenuation of thrombin-induced EC permeability and contractile response, whereas PGI2 effectively suppressed thrombin-induced permeability but was less efficient in the attenuation of prolonged EC hyperpermeability caused by interleukin-6 or bacterial wall lipopolysaccharide, LPS. PGD2 showed a modest protective effect on the EC inflammatory response, whereas PGF2α and PGJ2 were without effect on agonist-induced EC barrier dysfunction. In vivo, PGE2, PGI2, and PGA2 attenuated LPS-induced lung inflammation, whereas PGF2α and PGJ2 were without effect. Interestingly, PGD2 exhibited a protective effect in the in vivo model of LPS-induced lung injury. This study provides a comprehensive analysis of barrier-protective and anti-inflammatory effects of different prostaglandins on lung EC in vitro and in vivo and identifies PGE2, PGI2, and PGA2 as prostaglandins with the most potent protective properties.

scholarly journals Metformin-stimulated AMPK-α1 promotes microvascular repair in acute lung injury

2013 ◽  
Vol 305 (11) ◽  
pp. L844-L855 ◽  
Author(s):  
Ming-Yuan Jian ◽  
Mikhail F. Alexeyev ◽  
Paul E. Wolkowicz ◽  
Jaroslaw W. Zmijewski ◽  
Judy R. Creighton
Keyword(s):  
Endothelial Cells ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Ex Vivo ◽  
Endothelial Permeability ◽  
Beneficial Effects ◽  
Isolated Lung

Acute lung injury secondary to sepsis is a leading cause of mortality in sepsis-related death. Present therapies are not effective in reversing endothelial cell dysfunction, which plays a key role in increased vascular permeability and compromised lung function. AMP-activated protein kinase (AMPK) is a molecular sensor important for detection and mediation of cellular adaptations to vascular disruptive stimuli. In this study, we sought to determine the role of AMPK in resolving increased endothelial permeability in the sepsis-injured lung. AMPK function was determined in vivo using a rat model of endotoxin-induced lung injury, ex vivo using the isolated lung, and in vitro using cultured rat pulmonary microvascular endothelial cells (PMVECs). AMPK stimulation using N1-(α-d-ribofuranosyl)-5-aminoimidizole-4-carboxamide or metformin decreased the LPS-induced increase in permeability, as determined by filtration coefficient ( Kf) measurements, and resolved edema as indicated by decreased wet-to-dry ratios. The role of AMPK in the endothelial response to LPS was determined by shRNA designed to decrease expression of the AMPK-α1 isoform in capillary endothelial cells. Permeability, wounding, and barrier resistance assays using PMVECs identified AMPK-α1 as the molecule responsible for the beneficial effects of AMPK in the lung. Our findings provide novel evidence for AMPK-α1 as a vascular repair mechanism important in the pulmonary response to sepsis and identify a role for metformin treatment in the management of capillary injury.

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