Fibronectin attenuates increased endothelial monolayer permeability after RGD peptide, anti-alpha 5 beta 1, or TNF-alpha exposure

1995 ◽  
Vol 269 (2) ◽  
pp. L248-L260 ◽  
Author(s):  
T. M. Curtis ◽  
P. J. McKeown-Longo ◽  
P. A. Vincent ◽  
S. M. Homan ◽  
E. M. Wheatley ◽  
...  

Endothelial permeability can be altered by tumor necrosis factor-alpha (TNF-alpha), a cytokine released in association with inflammation-induced tissue injury. In the subendothelial matrix, fibronectin (Fn) influences endothelial cell adhesion by the interaction of integrins with RGD and non-RGD attachment sites in Fn. We compared the effect of TNF-alpha, RGD-containing peptides (GRGDSP), or antibody to alpha 5 beta 1-integrins on the protein permeability of bovine lung endothelial monolayers as assessed by transendothelial 125I-labeled albumin clearance. We also examined the influence of purified human plasma fibronectin (hFn) on this permeability response. TNF-alpha, RGD peptides, and antibodies to alpha 5 beta 1-integrins elicited a dose- and time-dependent increase in protein permeability as well as a reorganization and/or disruption of the endogenous Fn matrix. A control RGE peptide (GRGESP) as well as immunoglobulin G purified from nonimmune rabbit serum did not increase endothelial protein permeability or disrupt the endogenous fibrillar Fn pattern in the matrix. Likewise, a LDV peptide derived from the alternatively spliced type III connecting segment (IIICS) within bovine Fn (bFn) was unable to increase permeability of the bovine endothelial monolayer. Co-incubation of purified soluble hFn (300 or 600 micrograms/ml) with either TNF-alpha, the RGD peptide, or the antibody to alpha 5 beta 1-integrins prevented the increase in endothelial permeability. This protective effect was also observed when the purified hFn (600 micrograms/ml) was added after the TNF-alpha-induced increase in endothelial permeability had taken place. Immunofluorescent analysis confirmed the incorporation of the hFn into the subendothelial matrix and its co-localization with the endogenous bFn. The similar alteration of the subendothelial matrix after exposure to RGD peptides, anti-alpha 5 beta 1-antibodies, or TNF-alpha, coupled with the ability for hFn to attenuate the permeability increase typically elicited by all three agents, suggests that disruption of cell-matrix interactions may be the mechanism by which TNF-alpha alters endothelial permeability.

1993 ◽  
Vol 265 (2) ◽  
pp. L148-L157 ◽  
Author(s):  
E. M. Wheatley ◽  
P. J. McKeown-Longo ◽  
P. A. Vincent ◽  
T. M. Saba

Plasma fibronectin, a dimeric adhesive protein in blood, incorporates into the subendothelial and interstitial matrix in the lung especially during vascular injury. Fibronectin in the matrix is believed to influence cell-cell interaction and endothelial cell adhesion to the collagen-rich extracellular matrix. We previously observed that addition of purified soluble human plasma fibronectin (hFn) to cultured pulmonary endothelial monolayers attenuates the increase in protein permeability of such monolayers exposed to tumor necrosis factor-alpha (TNF-alpha). In the current study, we determined the specificity of this permeability response to fibronectin by comparing hFn to two other purified adhesive proteins in human plasma, i.e., vitronectin (Vn) and fibrinogen (Fg). We also determined whether matrix incorporation was essential for this hFn-mediated protective response by comparing normal intact hFn to either hFn alkylated with N-ethylmaleimide (NEM) or to purified 160/180-kDa hFn fragments, since these alternate forms of fibronectin are believed to exhibit limited ability to incorporate into matrix. Calf pulmonary artery endothelial (CPAE) monolayers (3-4 days postseeding) were exposed to human recombinant TNF-alpha for 18 h at a medium concentration of 200 U/ml followed by assessment of protein permeability using transendothelial 125I-labeled albumin clearance. Dimeric hFn (600 micrograms/ml) significantly (P < 0.05) reduced the TNF-induced increase in endothelial monolayer permeability. Vn or Fg, added at equal molar concentrations to the hFn, were unable to attenuate endothelial permeability. Immunofluorescent analysis utilizing antibodies specific to either hFn, human Vn, or human Fg revealed incorporation of the exogenous hFn into the extracellular matrix, but no matrix incorporation of Vn or Fg. Both NEM-treated dimeric hFn as well as purified 160/180-kDa fragments of hFn, which cannot incorporate into the matrix, were also unable to prevent the TNF-induced increase in protein permeability. Thus the ability for soluble hFn to reduce the TNF-induced increase in lung endothelial monolayer permeability was specific and dependent on its incorporation into the extracellular matrix.


1992 ◽  
Vol 263 (6) ◽  
pp. L627-L633 ◽  
Author(s):  
C. A. Partridge ◽  
C. J. Horvath ◽  
P. J. Del Vecchio ◽  
P. G. Phillips ◽  
A. B. Malik

We examined the possibility that alterations of the extracellular matrix (ECM) contribute to the tumor necrosis factor-alpha (TNF-alpha)-induced increase in endothelial monolayer permeability. Endothelial permeability to 125I-labeled albumin was determined using bovine pulmonary microvessel endothelial cell (BPMVE) monolayers grown to confluence on microporous (0.8 microns diam) gelatin- and fibronectin-coated polycarbonate filters. Treatment of BPMVE with TNF-alpha (10(2) to 10(4) U/ml for 4–24 h) produced concentration- and time-dependent increases in endothelial permeability that paralleled the changes in morphology from cobblestone to elongated cells and the formation of prominent intercellular gaps and actin stress fibers. We examined the role of ECM in these changes using filters coated with ECM made by the BPMVE. Fresh BPMVE seeded onto filters coated with ECM produced by TNF-alpha-treated BPMVE had two- to threefold higher 125I-albumin permeability values than BPMVE monolayers seeded onto filters coated with ECM from control cells (P < 0.05). BPMVE seeded onto ECM from TNF-alpha-treated BPMVE also developed intercellular gaps and centralized actin filaments characteristic of the TNF-alpha-treated BPMVE. This effect was not attributable to TNF-alpha adsorbed to ECM. Polyacrylamide gel electrophoresis of ECM extracted from BPMVE treated with TNF-alpha showed decreased fibronectin. These findings suggest that the TNF-alpha-induced increase in endothelial permeability involves the loss of fibronectin and remodeling of the ECM. The increase in endothelial permeability may be secondary to decreased endothelial cell-ECM contacts resulting in elongation of cells and formation of intercellular gaps.


1995 ◽  
Vol 269 (1) ◽  
pp. R160-R166 ◽  
Author(s):  
W. Ertel ◽  
M. H. Morrison ◽  
A. Ayala ◽  
I. H. Chaudry

Although hemorrhagic shock causes a significant elevation of circulating levels of proinflammatory cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-1 beta, IL-6], it remains unknown whether hypoxemia per se in the absence of blood loss activates macrophages (Mo) to release increased amounts of these mediators. To study this, hypoxemia was induced in C3H/HeN mice by placing them in a plastic box that was flushed with a gas mixture containing 95% N2-5% O2 for 60 min, followed by return of the mice to room air. For control animals, the plastic box was flushed with room air. At 0, 2, or 24 h thereafter, blood samples were obtained, plasma was separated, and then peritoneal Mo (pMo) and Kupffer cells (KC) were isolated and incubated at 37 degrees C for 24 h with lipopolysaccharide. The Mo supernatants, as well as plasma samples, were assayed for TNF-alpha, IL-1 beta, and IL-6 with the use of specific bioassays. Hypoxemia induced a significant (P < 0.05) increase in plasma TNF-alpha levels during the entire study period while circulating IL-6 was elevated by 313% (P < 0.01) at 24 h after hypoxemia compared with shams. Moreover, the release of TNF-alpha, IL-1 beta, and IL-6 by pMo and KC was markedly increased after hypoxemia compared with shams. Thus, hypoxemia in itself, in the absence of any blood loss or tissue injury, induces release of proinflammatory cytokines, which may contribute to systemic inflammation following hypoxemia.


1997 ◽  
Vol 272 (3) ◽  
pp. L385-L393 ◽  
Author(s):  
C. A. Owen ◽  
M. A. Campbell ◽  
S. S. Boukedes ◽  
E. J. Campbell

Membrane-bound leukocyte elastase activity on neutrophils may have potent proinflammatory effects. Herein, we report the effects of tumor necrosis factor-alpha (TNF-alpha), platelet-activating factor (PAF), N-formyl-leucyl-methionyl-phenylalanine (fMLP), and interleukin-8 (IL-8) on membrane-bound elastase expression. TNF-alpha or PAF alone induced only approximately two- to threefold increases in membrane-bound elastase but exhibited marked dose- and time-dependent priming effects for subsequent stimulation with fMLP or IL-8 (up to 20-fold increases in membrane-bound human leukocyte elastase compared with unstimulated cells). Optimally PAF-primed and fMLP-stimulated cells expressed 1.105 +/- 0.25 (SD) x 10(-17) mol [6.65 +/- 1.51 (SD) x 10(6) molecules] membrane-bound elastase activity/cell or approximately 12% of the content of unstimulated cells. Elastase binds to the cell surface by a charge-dependent mechanism since 1) incubation of cells with cationic molecules abrogated agonist-induced upregulation of membrane-bound elastase and 2) elastase was progressively eluted from the cell surface by solutions with increasing ionic strength. Thus interactions between proinflammatory mediators strikingly upregulate membrane-bound elastase on neutrophils, which may promote inflammatory responses and/or contribute to tissue injury.


1997 ◽  
Vol 272 (5) ◽  
pp. L979-L988 ◽  
Author(s):  
T. J. Ferro ◽  
N. Gertzberg ◽  
L. Selden ◽  
P. Neumann ◽  
A. Johnson

We tested the hypothesis that nitric oxide (.NO) mediates tumor necrosis factor-alpha (TNF-alpha)-induced alterations in permeability and actin of pulmonary artery endothelial monolayers (PAEM). The permeability of PAEM was assessed by the clearance rate of albumin labeled with Evans blue dye. The PAEM Triton-soluble ("cytoskeletal-nonassociated") and -insoluble ("cytoskeletal-associated") lysates were analyzed by Western blot for actin and oxidized protein using polyclonal antibodies to the COOH terminus of actin and dinitrophenylhydrazone (DNP), respectively. PAEM were incubated with TNF-alpha (100 U/ml) for 4 h. Incubation of PAEM with TNF-alpha resulted in increases in 1) the .NO oxidation product nitrite (NO2-), 2) nitrotyrosine immunofluorescence, 3) the oxidation of p42 (tentatively identified as actin), and 4) permeability to Evans blue dye-albumin. The .NO synthase inhibitor aminoguanidine (100 microM) prevented the TNF-alpha-induced increase in NO2-, nitrotyrosine immunofluorescence, oxidized p42, and permeability. Coincubation with L-arginine (200 microM) or the .NO mimic spermine-NO (1 microM) prevented the ablation of the response to TNF-alpha by aminoguanidine. The data indicate that TNF-alpha-induced increases in endothelial permeability and oxidized protein are mediated by .NO in PAEM.


1993 ◽  
Vol 265 (5) ◽  
pp. L438-L447 ◽  
Author(s):  
C. A. Partridge ◽  
J. J. Jeffrey ◽  
A. B. Malik

Tumor necrosis factor-alpha (TNF-alpha) may increase vascular endothelial permeability through alteration of the extracellular matrix (ECM). Incubation of bovine pulmonary microvascular endothelial (BPMVE) cells grown to confluence on microporous filters with 10(4) U/ml TNF-alpha for 24 h increased monolayer permeability to 125I-labeled albumin two- to threefold. TNF-alpha treatment also induced expression of a 96-kDa gelatinolytic metalloproteinase that was present in the medium and bound to the ECM. The induced 96-kDa metalloproteinase was purified from conditioned medium and found to cleave fibronectin, laminin, types IV and V collagens, and gelatins from types I and III collagens, suggesting identity as a type IV collagenase-gelatinase. Incubation of BPMVE cells with the 96-kDa gelatinase increased monolayer permeability, an effect prevented by inclusion of either tissue inhibitor of metalloproteinase (TIMP) or 1,10-phenanthroline. When BPMVE cells were incubated with the 96-kDa gelatinase or 10(4) U/ml TNF-alpha and then stripped from the filters, the remaining ECM displayed increased permeability to 125I-albumin compared with matrix from untreated BPMVE. The ECM extracts from both TNF-alpha- and enzyme-treated cells were found to contain less fibronectin, whereas their total protein contents were similar to those of untreated controls. These results suggest that the 96-kDa metalloproteinase induced by TNF-alpha contributes to increased vascular endothelial permeability through the degradation of specific extracellular matrix components.


1997 ◽  
Vol 8 (4) ◽  
pp. 596-603 ◽  
Author(s):  
J A Satriano ◽  
B Banas ◽  
B Luckow ◽  
P Nelson ◽  
D O Schlondorff

Chemokines and adhesion molecules play a pivotal role in leukocyte infiltration during tissue injury. RANTES (regulated upon activation, normal T cell expressed and secreted) is a monocyte chemoattractant that induces the expression of CD11/CD18 integrins on leukocytes for which intercellular adhesion molecule-1 (ICAM-1) is the ligand. Both RANTES and ICAM-1 can be expressed by mesangial cells (MC) in culture and in glomeruli during immune injury. In this study, the role of reactive oxygen species (ROS) in the activation of RANTES and ICAM-1 in murine MC was examined. Tumor necrosis factor alpha (TNF-alpha) and aggregated immunoglobulin (aggr. Ig) G, which enhance ROS formation in MC, increased mRNA transcripts of both RANTES and ICAM-1. Thiol-containing free-radical scavengers N-acetyl cysteine, dimethyl- and tetramethylthiourea, or pyrrolidinedithiocarbamate abrogated the increase in mRNA for RANTES and ICAM-1 in response to TNF-alpha or IgG. Hydroxy-methoxy acetophenone, an inhibitor of NADPH-dependent oxidase, also attenuated RANTES and ICAM-1 in response to TNF-alpha or IgG. ROS generated by addition of xanthine oxidase and hypoxanthine induced RANTES and ICAM-1 expression, whereas hydrogen peroxide caused no response. Because cAMP can interfere with gene activation in MC, the effects of 8-Br-cAMP, forskolin, and prostaglandin E2 on mRNA levels were examined for RANTES and ICAM-1. These agents attenuated the response to IgG aggregates and also to superoxide generation. Finally, the effect of glucocorticoids, which are frequently used in glomerular immune injury, was examined. Dexamethasone decreased mRNA for both RANTES and ICAM-1 after stimulation with aggr. IgG or TNF-alpha. Both forskolin and dexamethasone also reduced the amount of RANTES protein secreted by MC in response to aggr. IgG. Only dexamethasone decreased RANTES secretion in response to TNF-alpha stimulation. The inhibitory effects of cAMP and dexamethasone may explain the beneficial effects of cAMP mimetics, such as prostaglandin E2 and glucocorticoid administration on glomerular inflammatory processes.


1991 ◽  
Vol 261 (4) ◽  
pp. H1226-H1230 ◽  
Author(s):  
R. A. Kaslovsky ◽  
L. Gibbs ◽  
A. B. Malik

Studies of neutrophil-dependent endothelial injury were made using normal neutrophils (nl-PMN, i.e., normal polymorphonuclear neutrophils) and PMN obtained from a patient with X-linked chronic granulomatous disease (CGD-PMN). Layering of nl-PMN on bovine pulmonary microvessel endothelial monolayers (ratio 10:1) followed by challenge with phorbol 12-myristate 13-acetate (PMA; 5 x 10(-9) M) resulted in a 190% increase in 125I-labeled albumin permeability across the monolayers. Pretreatment of endothelial monolayers with tumor necrosis factor-alpha (TNF-alpha; 200 or 1,000 U/ml) further enhanced the increase in permeability after stimulation of nl-PMN with PMA. In contrast, challenge of CGD-PMN layered on endothelial cells with PMA did not increase permeability, and the effect was not enhanced by pretreating the endothelial cells with TNF-alpha. Nl-PMN, but not CGD-PMN, generated superoxide anion on stimulation with PMA (42.5 +/- 0.7 vs. 6.5 +/- 0.6 nM.10(6) PMN-1.h-1). PMA also induced degranulation of nl-PMN as measured by release of elastase (2.32 +/- 0.12 micrograms/10(6) PMN) and myeloperoxidase (173.8 +/- 1.9 U/10(6) PMN) into the medium, whereas release by CGD-PMN was markedly reduced (elastase release of 0.88 +/- 0.04 microgram/10(6) PMN and myeloperoxidase release of 82.6 +/- 19.4 U/10(6) PMN). The adherence response of nl-PMN and CGD-PMN to the endothelial cells after PMA stimulation was similar (79.5 +/- 11.8% nl-PMN and 64.0 +/- 1.9% CGD-PMN). Therefore, the PMN respiratory burst, with the resultant generation of oxidants and PMN-derived proteases, is required to increase endothelial permeability even in the face of increased endothelial adhesivity.


2018 ◽  
Vol 69 (7) ◽  
pp. 1830-1837
Author(s):  
Cristian Nicolescu ◽  
Alaxendru Pop ◽  
Alin Mihu ◽  
Luminita Pilat ◽  
Ovidiu Bedreag ◽  
...  

This article presents an observational randomized prospective study done on 65 patients, who underwent major surgical interventions in the field of orthopedic surgery-total hip replacement or general surgery � total colectomy. The level of albuminemia in these cases were determined before the surgical intervention, after 6 hours of the intervention and after 24 h of the intervention. The measurements of the plasmatic concentration of the pro-inflammatory cytokines Tumor Necrosis factor -alpha (TNF-alpha) and interleukin 6 (IL6) were simultaneously done with the determination of the plasmatic levels of albumin. Values of hemoglobin and hematocrit were determined 24 h after the surgical procedure in order to exclude hemodilution, which could lead to a possible drop in the levels of plasmatic albumin. After the collection of the data, the statistical work was done and it consisted of descriptive statistics, correlation and comparison tests as well as statistical validation tests. Obtained results indicate that IL-6 plays a major role comparatively with that of TNF-alfa, regarding the decrease of the plasmatic level of albumin, and due to this, the primordial cause for hypoalbuminemia is an acute hepatic phase reaction. Supplemental permeability of the capillary wall under the action of TNF alpha has a secondary role, but could lead to a faster decrease in plasmatic albumin in the first hours after the surgical procedure.


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