scholarly journals Human Endothelial Cell Injury Mechanisms in Vitro

1977 ◽  
Author(s):  
R.T. Wall ◽  
L.A. Harker ◽  
G. Striker ◽  
L. Quadracci
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Dose Response ◽  
Cell Injury ◽  
Cultured Cells ◽  
Test Material ◽  
51Cr Release ◽  
Injury Mechanisms ◽  
Cell Antibody

Since endothelial cell desquamation constitutes the initial event leading to acute and chronic vascular diseases, we have developed an in vitro system for studying injury mechanisms using cultured cells. The system involves the incubation of test material with confluent, 51Cr-labeled, cultured human umbilical vein endothelial cells in 100% pooled human serum; injury was measured as% endothelial cell 51Cr release (ECR) into the supernatant media. Baseline spontaneous ECR was 6.0% ± 1.5 while specific rabbit antihuman endothelial cell antibody (1:64 dilution) in the presence of fresh complement released 90% ± 3 of the total releasable 51Cr activity. Consistent with in vivo predictions, homocysteine in concentrations of 0.5-40 mM iduced dose response ECR up to 20%. Neither methionine nor homocystine increased ECR over controls. Also as expected from experimental work endotoxin (S. enteritidis) caused dose response ECR, i.e., 24% ± 2 at 10 ug/ml. Control studies with cultured human smooth muscle cells (SMC) demonstrated no ECR with homocysteine but significant release occurred with endotoxin.Specific complement dependent cytotoxic anti-endothelial cell antibody was demonstrated in the secum of two thrombotic thrombocytopenic purpura (TTP) patients at a 1:1 dilution, inducing ECR of 23.1% ± 1.4 and 21.0% ± 0.25. The antibody was also demonstrated by immunoflourescent techniques and was absorbed from the serum using human endothelial cells. One disease-free, six month survivor showed no cytotoxic activity. Serum from a patient with adult hemolytic-uremic syndrome demonstrated antibody dependent cell mediated cytotoxicity with release of 22% ± 1.1 when normal non-immune lymphocytes were added to heat inactivated seriun. Control studies with SMC showed no ECR with TTP sera. We conclude that assays of endothelial cell 51Cr release are stable, reproducible and useful in the characterization of injury mechanisms.

scholarly journals Atherosclerosis-Associated Endothelial Cell Apoptosis by MiR-429-Mediated Down Regulation of Bcl-2

2015 ◽  
Vol 37 (4) ◽  
pp. 1421-1430 ◽  
Author(s):  
Tao Zhang ◽  
Feng Tian ◽  
Jing Wang ◽  
Jing Jing ◽  
Shan-Shan Zhou ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Apoptosis ◽  
Cell Injury ◽  
Luciferase Reporter ◽  
Lower Percentage ◽  
Endothelial Cell Apoptosis ◽  
Down Regulation ◽  
Bioinformatics Analyses

Background/Aims: Endothelial cell injury and subsequent apoptosis play a key role in the development and pathogenesis of atherosclerosis, which is hallmarked by dysregulated lipid homeostasis, aberrant immunity and inflammation, and plaque-instability-associated coronary occlusion. Nevertheless, our understanding of the mechanisms underlying endothelial cell apoptosis is still limited. MicroRNA-429 (miR-29) is a known cancer suppressor that promotes cancer cell apoptosis. However, it is unknown whether miR-429 may be involved in the development of atherosclerosis through similar mechanisms. We addressed these questions in the current study. Methods: We examined the levels of endothelial cell apoptosis in ApoE (-/-) mice suppled with high-fat diet (HFD), a mouse model for atherosclerosis (simplified as HFD mice). We analyzed the levels of anti-apoptotic protein Bcl-2 and the levels of miR-429 in the purified CD31+ endothelial cells from mouse aorta. Prediction of the binding between miR-429 and 3'-UTR of Bcl-2 mRNA was performed by bioinformatics analyses and confirmed by a dual luciferase reporter assay. The effects of miR-429 were further analyzed in an in vitro model using oxidized low-density lipoprotein (ox-LDL)-treated human aortic endothelial cells (HAECs). Results: HFD mice developed atherosclerosis in 12 weeks, while the control ApoE (-/-) mice that had received normal diet (simplified as NOR mice) did not. HFD mice had significantly lower percentage of endothelial cells and significantly higher percentage of mesenchymal cells in the aorta than NOR mice. Significantly higher levels of endothelial cell apoptosis were detected in HFD mice, resulting from decreases in Bcl-2 protein, but not mRNA. The decreases in Bcl-2 in endothelial cells were due to increased levels of miR-429, which suppressed the translation of Bcl-2 mRNA via 3'-UTR binding. These in vivo findings were reproduced in vitro on ox-LDL-treated HAECs. Conclusion: Atherosclerosis-associated endothelial cell apoptosis may result from down regulation of Bcl-2, through increased miR-429 that binds and suppresses translation of Bcl-2 mRNA.

An in vitro model of ischemia/reperfusion-induced microvascular injury

1990 ◽  
Vol 259 (1) ◽  
pp. G134-G139 ◽  
Author(s):  
W. Inauen ◽  
D. N. Granger ◽  
C. J. Meininger ◽  
M. E. Schelling ◽  
H. J. Granger ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
In Vitro Model ◽  
Cell Injury ◽  
Ischemia Reperfusion ◽  
In Vivo Studies ◽  
Cell Detachment ◽  
51Cr Release ◽  
Vitro Model

The major objective of this study was to develop an in vitro model of ischemia/reperfusion (I/R)-induced microvascular injury. Cultured venular endothelial cells were grown to confluency, labeled with 51Cr, and exposed to different durations of anoxia (0.5, 1, 2, 3, and 4 h). 51Cr release and cell detachment (indexes of cell injury) were determined at different times after reoxygenation (1, 2, 4, 6, 8, and 18 h). Because in vivo studies have implicated neutrophils in I/R injury, in some experiments human neutrophils were added to the endothelial cells upon reoxygenation. Periods of anoxia greater than or equal to 2 h resulted in 70-80% 51Cr release and 80-95% cell detachment upon reoxygenation. Under these conditions (near maximal injury), the addition of neutrophils produced negligible effects. Periods of anoxia less than or equal to 1 h resulted in 30-40% 51Cr release and 50-60% cell detachment. Under these conditions (moderate cell injury), addition of neutrophils enhanced endothelial cell injury. Using a 30-min period of anoxia, we also assessed the effects of superoxide dismutase (SOD; 300 U/ml) and allopurinol (20 microM) on anoxia/reoxygenation (A/R)-induced injury in the presence or absence of neutrophils. In the absence of neutrophils, SOD or allopurinol did not protect against A/R-induced injury. However, in the presence of neutrophils, both SOD and allopurinol attenuated the increases in 51Cr release. The results derived using this in vitro model of I/R injury are largely consistent with published in vivo studies. Thus this in vitro model may provide further insights regarding the mechanisms involved in I/R injury.

scholarly journals MO017THERAPEUTICAL POTENTIAL OF ENZYME REPLACEMENT: NEW INSIGHTS AND PERSPECTIVES IN HUMAN ENDOTHELIAL CELLS TREATED WITH CHLOROQUINE

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Paulo C Gregorio ◽  
Regiane Cunha ◽  
Gilson Biagini ◽  
Bruna Bosquetti ◽  
Julia Budag ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Biology ◽  
Cell Injury ◽  
No Production ◽  
In Vitro Test ◽  
Human Endothelial Cells ◽  
Enzyme Replacement ◽  
Agalsidase Β

Abstract Background and Aims COVID-19 is a pandemic with no end in sight. There is only one approved antiviral agent but global stocks are deemed insufficient. Despite in vitro antiviral activity, clinical trials of chloroquine and hydroxychloroquine were disappointing, and they may even impair outcomes. Chloroquine causes zebroid deposits reminiscent of Fabry disease (α-galactosidase A deficiency) and endothelial cells are key targets of COVID-19. The study aims to investigate in vitro the effect of enzyme replacement therapy (ERT) in chloroquine-induced endothelial dysfunction. Method We have explored the effect of chloroquine on cultured endothelial cells and its modulation by recombinant α-galactosidase A (agalsidase-β). Following dose-response studies, 0.5 μg/mL chloroquine was added to cultured human endothelial cells. Neutral red and Lysotracker were used to assess lysosomes. Cytotoxicity was evaluated by the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) - MTT assay and cell stress by assessing reactive oxygen species (ROS) and nitric oxide (NO). In endothelial cells, chloroquine induced dose-dependent cytotoxicity at in vitro test concentrations for COVID-19 therapy. Results Chloroquine significantly induced the accumulation of acid organelles (P<0.05), increased ROS levels, and decreased NO production (P<0.05), in vitro. These adverse effects of chloroquine on endothelial cell biology were decreased by agalsidase-β (P<0.05). Conclusion Chloroquine-induced endothelial cell cytotoxicity and stress is attenuated by agalsidase-β treatment. This suggests that endothelial cell injury may contribute to the failure of chloroquine as therapy for COVID-19 and may be at least in part related to causing dysfunction of the lysosomal enzyme α-galactosidase A.

scholarly journals Endothelial Cell Autophagy in Atherosclerosis is Regulated by miR-30-Mediated Translational Control of ATG6

2015 ◽  
Vol 37 (4) ◽  
pp. 1369-1378 ◽  
Author(s):  
Tao Zhang ◽  
Feng Tian ◽  
Jing Wang ◽  
Jing Jing ◽  
Shan-Shan Zhou ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Translational Control ◽  
Cell Injury ◽  
Protein Translation ◽  
Luciferase Reporter ◽  
Protective Effects ◽  
Bioinformatics Analyses

Background/Aims: Endothelial cell injury and subsequent death play an essential role in the pathogenesis of atherosclerosis. Autophagy of endothelial cells has a protective role against development of atherosclerosis, whereas the molecular regulation of endothelial cell autophagy is unclear. MicroRNA-30 (miR-30) is a known autophagy suppressor in some biological processes, while it is unknown whether this regulatory axis may be similarly involved in the development of atherosclerosis. Here, we aimed to answer these questions in the current study. Methods: We examined the levels of endothelial cell autophagy in ApoE (-/-) mice suppled with high-fat diet (HFD), a mouse model for atherosclerosis (simplified as HFD mice). We analyzed the levels of autophagy-associated protein 6 (ATG6, or Beclin-1) and the levels of miR-30 in the purified CD31+ endothelial cells from mouse aorta. Prediction of the binding between miR-30 and 3'-UTR of ATG6 mRNA was performed by bioinformatics analyses and confirmed by a dual luciferase reporter assay. The effects of miR-30 were further analyzed in an in vitro model using oxidized low-density lipoprotein (ox-LDL)-treated human aortic endothelial cells (HAECs). Results: HFD mice developed atherosclerosis in 12 weeks, while the control ApoE (-/-) mice that had received normal diet (simplified as NOR mice) did not. Compared to NOR mice, HFD mice had significantly lower levels of endothelial cell autophagy, resulting from decreases in ATG6 protein, but not mRNA. The decreases in ATG6 in endothelial cells were due to HFD-induced increases in miR-30, which suppressed the translation of ATG6 mRNA via 3′-UTR binding. These in vivo findings were reproduced in vitro on ox-LDL-treated HAECs. Conclusion: Upregulation of miR-30 by HFD may impair the protective effects of endothelial cell autophagy against development of atherosclerosis through suppressing protein translation of ATG6.

The associations of endothelial and podocyte injury in proliferative lupus nephritis: from observational analysis to in vitro study

Lupus ◽  
2019 ◽  
Vol 28 (3) ◽  
pp. 347-358 ◽  
Author(s):  
M Yuan ◽  
Y Tan ◽  
Y Wang ◽  
S X Wang ◽  
F Yu ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Injury ◽  
In Vitro Study ◽  
Glomerular Endothelial Cell ◽  
Endothelial Cell Injury ◽  
Endothelin 1 ◽  
Glomerular Endothelial Cells ◽  
Proliferative Lupus Nephritis

Our study aims to evaluate the endothelial cell-podocyte crosstalk in proliferative lupus nephritis (LN). The semi-quantification scores of glomerular endothelial cell injury and the foot process width (FPW) were processed in 110 proliferative LN patients. Podocytes were stimulated with LN-derived IgG. Glomerular endothelial cells were treated with podocyte-conditioned medium (PCM), and then podocytes were incubated with endothelial cell–conditioned medium (ECM). The levels of vascular endothelial growth factor-A (VEGF-A) in PCM and endothelin-1 in ECM were analyzed, and the injury of podocyte and glomerular endothelial cells were further evaluated. The pathological score of glomerular endothelial cell injury was correlated with FPW in LN complicated with thrombotic microangiopathy. In vitro study showed the following: 1. Stimulation of podocytes by IgG from LN led to decline in the expression of nephrin with cytoskeleton rearrangement, and reduction of VEGF-A levels. 2. Exposure of glomerular endothelial cells to PCM incubated with LN-derived IgG (PCM-LN) induced more endothelin-1 secretion and disruption of intercellular tight junction. 3. Exposure of podocytes to ECM stimulated with PCM-LN could induce cytoskeleton redistribution with decrease of nephrin. In conclusion, the pathological glomerular endothelial cell lesions were associated with FPW and the VEGF-endothelin-1 system might play a critical role in the endothelial cell-podocyte crosstalk in LN.

Panax Quinquefolium L. Inhibits Thrombin-Induced Endothelin Release In Vitro

1999 ◽  
Vol 27 (03n04) ◽  
pp. 331-338 ◽  
Author(s):  
Chun-Su Yuan ◽  
Anoja S. Attele ◽  
Ji An Wu ◽  
Tasha K. Lowell ◽  
Zhenlun Gu ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Injury ◽  
Vascular Endothelial Cells ◽  
Cell Damage ◽  
Umbilical Vein ◽  
American Ginseng ◽  
Protective Effects ◽  
Panax Quinquefolium

Endothelial cell damage is considered to be the initial step in the genesis of thrombosis and arteriosclerosis, the common precursors of cardiovascular disorders. In this study, we evaluated the protective effects of American ginseng or Panax quinquefolium L. extracts on endothelial cell injury, and investigated effects of ginseng extracts on thrombin-induced endothelin release using cultured human umbilical vein endothelial cells. We observed that when endothelial cells pretreated with 1, 10, and 100 μg/ml of Panax quinquefolium L. extracts were incubated for 4 and 24 hr with thrombin, the concentration of endothelin was significantly decreased in a concentration dependent, time related manner (at 4 hr, IC50 = 5.1 μg/ml; at 24 hr, IC50 = 6.2 μg/ml). We further evaluated the effects of NG-nitro-L-arginine (NLA), a nitric oxide (NO) synthetase inhibitor, on the activity of Panax quinquefolium L. extracts. Following pretreatment of cultured endothelial cells with NLA, the inhibition of thrombin-induced endothelin release by Panax quinquefolium L. was significantly reduced (P < 0.05). This result suggests that the pharmacological action of Panax quinquefolium L. is, at least partially, due to NO release. Our data demonstrate that American ginseng may play a therapeutic role in facilitating the hemodynamic balance of vascular endothelial cells.

Human serum catalase decreases endothelial cell injury from hydrogen peroxide

1991 ◽  
Vol 71 (5) ◽  
pp. 1903-1906 ◽  
Author(s):  
J. A. Leff ◽  
M. A. Oppegard ◽  
L. S. Terada ◽  
E. C. McCarty ◽  
J. E. Repine
Keyword(s):  
Hydrogen Peroxide ◽  
Endothelial Cells ◽  
Endothelial Cell ◽  
Catalase Activity ◽  
Trichloroacetic Acid ◽  
Cell Injury ◽  
Human Subjects ◽  
Endothelial Cell Injury ◽  
Normal Human

Serum from normal human subjects contained variable amounts of catalase activity, which was inhibitable by heat, azide, trichloroacetic acid (TCA), or aminotriazole treatment. Serum also decreased hydrogen peroxide (H2O2) concentrations in vitro and H2O2-mediated injury to cultured endothelial cells. By comparison, heat-, azide-, TCA-, or aminotriazole-treated serum neither decreased H2O2 concentrations in vitro nor reduced H2O2-mediated damage to endothelial cells. We conclude that serum catalase activity can alter H2O2-dependent reactions. We speculate that variations in serum catalase activity may alter individual susceptibility to oxidant-mediated vascular disease or be a factor when added to test systems in vitro.

Anoxia-reoxygenation-induced, neutrophil-mediated endothelial cell injury: role of elastase

1990 ◽  
Vol 259 (3) ◽  
pp. H925-H931 ◽  
Author(s):  
W. Inauen ◽  
D. N. Granger ◽  
C. J. Meininger ◽  
M. E. Schelling ◽  
H. J. Granger ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Cell Injury ◽  
Cell Detachment ◽  
51Cr Release ◽  
Microvascular Endothelium ◽  
Endothelial Cell Injury ◽  
Cell Dysfunction ◽  
Neutrophilic Elastase

The aim of this study was to assess the role of neutrophilic elastase in anoxia-reoxygenation-induced, neutrophil-mediated injury to microvascular endothelium. Cultured bovine microvascular endothelial cells were grown to confluence and labeled with 51Cr. The endothelial cells were exposed to a 30-min period of anoxia and subsequently reoxygenated. Endothelial cell injury, quantitated as 51Cr release and cell detachment, was determined 8 h after reoxygenation. Addition of neutrophils upon reoxygenation enhanced the anoxia-reoxygenation-induced increase in 51Cr release and cell detachment. The neutrophil-mediated injury was associated with elastase release from the neutrophils. Four agents were used to inhibit neutrophilic elastase activity: Eglin C, methoxysuccunyl-Ala2-Pro-Val-CH2Cl, L658,758, and a monoclonal antibody against neutrophilic elastase. All elastase inhibitors attenuated the neutrophil-mediated endothelial cell detachment but not 51Cr release. Addition of purified human neutrophilic elastase, at a level that mimicked the release from neutrophils, increased cell detachment in endothelial cells exposed to anoxia-reoxygenation but did not affect 51Cr release. Our results indicate that elastase plays an important role in anoxia-reoxygenation-induced, neutrophil-mediated endothelial cell dysfunction.

Astrocyte-Plexus Is Formed in the Neovascularization Induced by CD11b+ Cells From An Ischemic Hind-Limb Mouse Model.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3043-3043
Author(s):  
Jeong A. Kim ◽  
Oak Kee Hong ◽  
Jong Wook Hong ◽  
Hal E. Broxmeyer
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Growth Factor ◽  
Vessel Wall ◽  
Cultured Cells ◽  
Conflicts Of Interest ◽  
Smooth Muscle Actin ◽  
Myeloid Cells ◽  
Artery Dissection

Abstract Abstract 3043 Poster Board II-1019 Angiogenic sprouting needs to navigate through tissues to establish a vascular branching pattern. Such angiogenic guidance is mainly inferred by nonrandom angiogenic sprouting in the developing central nervous system (CNS). In mammalian retina, a vascular plexus initially forms, superimposed on a preexisting astrocyte-plexus, and retinal astrocytes begin to express vascular endothelial growth factor (VEGF-A), which stimulates endothelial cells to sprout radially from the optic nerve head into the retinal periphery. However, there has been little investigation of the role of astrocyte-plexus in new vessel formation of other ischemic sites besides retina. We recently found that infiltrated CD11b+ cells in ischemic muscles differentiate into endothelial-like cells in vitro, and that direct-injection of muscle-derived CD11b+ cells enhances recovery of blood perfusion in ischemic hind-limbs of C57BL/6 mice. To study if the astrocytes are related to the neovascularization process in ischemic limbs, infiltrated CD11b+ myeloid-cells in ischemic muscles were isolated 4 days after femoral artery dissection, and then seeded at 0.5×105/cm2 onto Matrigel and cultured in EGM-2 medium. Under these conditions, we tested the following hypotheses: (1) cultured cells initially form an astrocyte-network in vitro, and (2) astrocytes are involved in the formation of vascular structure. Seven days after the cells were embedded in Matrigel, spindle shaped cells grew, spread-out radially from cell clusters to the periphery, and established a mesh-like network expressing glial fibrillary acidic protein (GFAP), a marker for astrocyte. These spindle shaped cells were also positive for pericyte markers: desmin, NG-2, and platelet-derived growth factor receptor (PDGFR)-β. Interestingly, proliferating endothelial cells were closely associated with astrocytes by extension of endothelial cell filopodia on astrocytes. This observation is consistent that astrocyte scaffold guides extension of endothelial cell filopodia. Two weeks after cells were embedded in Matrigel, CD11b+ cells expanded and were layered in the same way to form vessel wall-like structures consisting of hundreds of cells. Spindle shaped GFAP-positive cells gradually expressed smooth muscle-actin at the bottom of the culture plate, migrated to the vessel wall-like structures, and covered the surface of the walls like pericytes. Taken together with the novel finding of astrocyte-like cell differentiation from CD11b+ cells from Matrigel culture, mobilization of CD11b+ myeloid-cells to regions of muscle ischemia would appear to play an important role in neovascularization after ischemic injury. Disclosures No relevant conflicts of interest to declare.

scholarly journals Structure and Function of a Vimentin-associated Matrix Adhesion in Endothelial Cells

2001 ◽  
Vol 12 (1) ◽  
pp. 85-100 ◽  
Author(s):  
Meredith Gonzales ◽  
Babette Weksler ◽  
Daisuke Tsuruta ◽  
Robert D. Goldman ◽  
Kristine J. Yoon ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Growth Factors ◽  
Endothelial Cell ◽  
Branching Morphogenesis ◽  
Basement Membranes ◽  
Αvβ3 Integrin ◽  
Dependent Manner ◽  
Matrix Adhesion ◽  
Focal Contacts

The α4 laminin subunit is a component of endothelial cell basement membranes. An antibody (2A3) against the α4 laminin G domain stains focal contact-like structures in transformed and primary microvascular endothelial cells (TrHBMECs and HMVECs, respectively), provided the latter cells are activated with growth factors. The 2A3 antibody staining colocalizes with that generated by αv and β3 integrin antibodies and, consistent with this localization, TrHBMECs and HMVECs adhere to the α4 laminin subunit G domain in an αvβ3-integrin–dependent manner. The αvβ3 integrin/2A3 antibody positively stained focal contacts are recognized by vinculin antibodies as well as by antibodies against plectin. Unusually, vimentin intermediate filaments, in addition to microfilament bundles, interact with many of the αvβ3 integrin-positive focal contacts. We have investigated the function of α4-laminin and αvβ3-integrin, which are at the core of these focal contacts, in cultured endothelial cells. Antibodies against these proteins inhibit branching morphogenesis of TrHBMECs and HMVECs in vitro, as well as their ability to repopulate in vitro wounds. Thus, we have characterized an endothelial cell matrix adhesion, which shows complex cytoskeletal interactions and whose assembly is regulated by growth factors. Our data indicate that this adhesion structure may play a role in angiogenesis.

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