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Sample records for endothelial cell lines

  1. Implantation of Vascular Grafts Lined with Genetically Modified Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Wilson, James M.; Birinyi, Louis K.; Salomon, Robert N.; Libby, Peter; Callow, Allan D.; Mulligan, Richard C.

    1989-06-01

    The possibility of using the vascular endothelial cell as a target for gene replacement therapy was explored. Recombinant retroviruses were used to transduce the lacZ gene into endothelial cells harvested from mongrel dogs. Prosthetic vascular grafts seeded with the genetically modified cells were implanted as carotid interposition grafts into the dogs from which the original cells were harvested. Analysis of the graft 5 weeks after implantation revealed genetically modified endothelial cells lining the luminal surface of the graft. This technology could be used in the treatment of atherosclerosis disease and the design of new drug delivery systems.

  2. Photodynamic effect of hypericin in primary cultures of human umbilical endothelial cells and glioma cell lines.

    PubMed

    Stupáková, Viktória; Varinská, Lenka; Mirossay, Andrej; Sarisský, Marek; Mojzis, Ján; Dankovcík, Róbert; Urdzík, Peter; Ostró, Alexander; Mirossay, Ladislav

    2009-06-01

    Hypericin is the most powerful naturally occurring photosensitizer and as such there is renaissant interest in the potentials of this compound for anticancer photodynamic therapy (PDT). The purpose of this study was to investigate the hypericin-mediated photodynamic therapy effects on normal human umbilical endothelial cells (HUVECs) in comparison with cancer human glioma cell lines U-87 MG and U-373 MG, in in vitro conditions. The data suggest that endothelial cells as well as glioma cell lines are sensitive only to photoactivated hypericin. The inhibitory effects of photoactivated hypericin did not differ in endothelial compared with tumor cells in cytotoxicity MTT and DNA fragmentation assays. However, an important difference in sensitivity was found between the above mentioned cell types in migration and metalloproteinases inhibition assays performed as cell function tests. The findings in both function tests were supported by the high sensitivity of endothelial cells in an additional angiogenesis test of tubular formation in vitro. PMID:19173218

  3. Ultrasound fails to induce proliferation of human brain and mouse endothelial cell lines

    NASA Astrophysics Data System (ADS)

    Rodemer, Claus; Jenne, Jürgen; Fatar, Marc; Hennerici, Michael G.; Meairs, Stephen

    2012-11-01

    Both in vitro and in vivo studies suggest that ultrasound (US) is capable of inducing angiogenesis. There is no information, however, on whether ultrasound can induce proliferation of brain endothelial cells. We therefore explored the angiogenic potential of ultrasound on a novel immortalised human brain endothelial cell line (hCMEC/D3) and on mouse brain microvascular endothelial cells (bEND3). Ultrasound failed to enhance cell proliferation in both cell lines at all acoustic pressures studied. Endothelial cell damage occurred at 0.24 MPa with significantly slower proliferation. Cells growing in Opticell{trade mark, serif} dishes did not show damage or reduced proliferation at these pressures.

  4. CD133 positive progenitor endothelial cell lines from human cord blood.

    PubMed

    Paprocka, Maria; Krawczenko, Agnieszka; Dus, Danuta; Kantor, Aneta; Carreau, Aude; Grillon, Catherine; Kieda, Claudine

    2011-08-01

    Endothelial progenitor cells (EPCs) modulate postnatal vascularization and contribute to vessel regeneration in adults. Stem cells and progenitor cells were found in umbilical cord blood, bone marrow, and mobilized peripheral blood cells, from where they were isolated and cultured. However, the yield of progenitor cells is usually not sufficient for clinical application and the quality of progenitor cells varies. The aim of the study was the immortalization of early progenitor cells with high proliferative potential, capable to differentiate to EPCs and, further, toward endothelial cells. Two cell lines, namely HEPC-CB.1 and HEPC-CB.2 (human endothelial progenitor cells-cord blood) were isolated. As assessed by specific antibody labeling and flow cytometric analysis, they express a panel of stem cell markers: CD133, CD13, CD271, CD90 and also endothelial cell markers: CD202b, CD309 (VEGFR2), CD146, CD105, and CD143 but they do not present markers of finally differentiated endothelial cells: CD31, vWf, nor CD45 which is a specific hematopoietic cell marker. Using the multiplex Cytometric Bead Assay, the simultaneous production of proangiogenic cytokines IL8, angiogenin, and VEGF was demonstrated in normoxia and was shown to be increased by hypoxia. Both cell lines, similarly as mature endothelial cells, underwent in vitro pre-angiogenic process, formed pseudovessel structures and present an accelerated angiogenesis in hypoxic conditions. To date, these are the first CD133 positive established cell lines from human cord blood cells. PMID:21710642

  5. Immortalized endothelial cell lines for in vitro blood-brain barrier models: A systematic review.

    PubMed

    Rahman, Nurul Adhwa; Rasil, Alifah Nur'ain Haji Mat; Meyding-Lamade, Uta; Craemer, Eva Maria; Diah, Suwarni; Tuah, Ani Afiqah; Muharram, Siti Hanna

    2016-07-01

    Endothelial cells play the most important role in construction of the blood-brain barrier. Many studies have opted to use commercially available, easily transfected or immortalized endothelial cell lines as in vitro blood-brain barrier models. Numerous endothelial cell lines are available, but we do not currently have strong evidence for which cell lines are optimal for establishment of such models. This review aimed to investigate the application of immortalized endothelial cell lines as in vitro blood-brain barrier models. The databases used for this review were PubMed, OVID MEDLINE, ProQuest, ScienceDirect, and SpringerLink. A narrative systematic review was conducted and identified 155 studies. As a result, 36 immortalized endothelial cell lines of human, mouse, rat, porcine and bovine origins were found for the establishment of in vitro blood-brain barrier and brain endothelium models. This review provides a summary of immortalized endothelial cell lines as a guideline for future studies and improvements in the establishment of in vitro blood-brain barrier models. It is important to establish a good and reproducible model that has the potential for multiple applications, in particular a model of such a complex compartment such as the blood-brain barrier. PMID:27086967

  6. Photodynamic response of an endothelial hybridoma cell line using zinc(II) tetrasubstituted phthalocyanines

    NASA Astrophysics Data System (ADS)

    Cruse-Sawyer, Janet E.; Dixon, B.; Roberts, David J.; Griffiths, John; Brown, Stanley B.

    1995-03-01

    The EAhy 926 cell is a hybridoma line derived from human endothelium and A549/8 cells. They display stable endothelial characteristics and may provide an indication of how endothelial cells respond to photodynamic therapy. Cells were grown as monolayers, seeded at a density of 104 cells/35 mm dish, and then incubated with zinc (II) tetrasubstituted phthalocyanines (carboxylated, sulphonated, pyridinium or diethanolamine sulphonamide). After 24 hours, the cells were illuminated with laser light at 680 nm or 692 nm as appropriate. The response to each photosensitizer was evaluated using cell proliferation, clonogenicity, and release of tissue factor.

  7. Study of apoptosis induced by cytostatics and vegetal extracts on human endothelial cell line.

    PubMed

    Bârzu, Simona Natalia; Bădulescu, Maria Mihaela; Lupu, Andreea Roxana; Cremer, Lidia; Szegli, G; Kerek, F; Călugăru, Ana

    2008-01-01

    Angiogenesis, the biological process by which new capillaries are formed from pre-existing vessels, is a tightly controlled and complex process involving several factors with both stimulating and inhibiting steps. In solid tumor growth, a specific clinical turning point is the transition to the vascular phase. Once it develops an intrinsic vascular network, a tumor grows indefinitely. Tumor angiogenesis depends mainly on the release by neoplasic cells of growth factors specific for endothelial cells (ECs), able to stimulate growth of the host blood vessels. The aim of this study was to analyze the apoptotic effect of some cytostatics, Vinblastine, Rapamycin and Doxorubicin, and vegetal extracts (called VOB) isolated and purified from Vitis sp., on human EA.hy926 endothelial cell line. In a proliferation assay using Crystal Violet, we demonstrated that Vinblastine and Rapamycin cytostatics have synergistic effect on endothelial cell line EA.hy926 growth inhibition. The inhibitory effects of Vinblastine and Doxorubicin were enhanced by VOB vegetal extracts. A combined treatment of cytostatics and VOB vegetal extracts resulted in a stronger antiproliferative effect of EA.hy926 endothelial cells. Results obtained regarding the apoptosis induced on EA.hy926 endothelial cells showed that each compound alone was able to induce a significant percent of apoptotic cells in a dose-dependent manner. PMID:19284159

  8. Development of a cell line from the American eel brain expressing endothelial cell properties.

    PubMed

    Bloch, Sophia R; Vo, Nguyen T K; Walsh, Sarah K; Chen, Cici; Lee, Lucy E J; Hodson, Peter V; Bols, Niels C

    2016-04-01

    A cell line (eelB) was developed from the outgrowth of adherent cells from brain explants of the American eel, Anguilla rostrata (Lesueur). EelB cells have been grown routinely in L-15 with 10% fetal bovine serum (FBS), undergone over 100 passages, and cryopreserved successfully. The cells from late-passage cultures (>45) were polygonal, formed capillary-like structures (CLS) on Matrigel, and stained immunocytochemically for von Willebrand factor (vWF) and for three tight junction proteins, zonula occludens-1 (ZO-1), claudin 3, and claudin 5. These results suggest that eelB is an endothelial cell line, one of the few from fish and the first from the brain. Despite this, eelB did not respond to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) with the induction of CYP1A protein. The cells from early-passage cultures (<20) had more varied shapes and did not form CLS on Matrigel. Only cells from early-passage cultures formed in suspension three-dimensional aggregates that had some cells expressing alkaline phosphatase and nestin. These cells are thought to be neural stem cells and the aggregates neurospheres. The emergence of endothelial-like cells upon the continued subcultivation of cells from early-passage cultures that had neural stem cells has been described previously for mammals, but this is a first for teleosts. Remarkably, cells from all passage levels were stained strongly for senescence-associated β-galactosidase (SA β-Gal) activity. PMID:26714751

  9. An immortalized human blood-nerve barrier endothelial cell line for in vitro permeability studies

    PubMed Central

    Yosef, Nejla; Ubogu, Eroboghene E.

    2012-01-01

    Solute and macromolecular transport studies may elucidate nutritional requirements and drug effects in healthy and diseased peripheral nerves. Endoneurial endothelial cells are specialized microvascular cells that form the restrictive blood-nerve barrier (BNB). Primary human endoneurial endothelial cells (pHEndECs) are difficult to isolate, limiting their widespread availability for biomedical research. We developed a simian virus-40 large T-antigen (SV40-LTA) immortalized human BNB cell line via stable transfection of low passage pHEndECs and observed continuous growth in culture for >45 population doublings. As observed with pHEndECs, the immortalized BNB endothelial cells were Ulex Europaeus agglutinin-1 (UEA-1)-positive and endocytosed low density lipoprotein, but lost von Willebrand factor (vWF) expression. Glucose transporter-1 (GLUT-1), P-glycoprotein (P-gp), γ-glutamyl transpeptidase (γ-GT), large neutral amino acid transporter-1 (LAT-1), creatine transporter (CRT) and monocarboxylate transporter-1 (MCT-1) mRNA expression were retained at all passages with loss of alkaline phosphatase (AP) expression after passages 16-20. Compared with an SV40-LTA immortalized human blood-brain barrier (BBB) endothelial cell line, there was increased γ-GT protein expression, equivalent expression of organic anion transporting polypeptide-C (OATP-C), organic anion transporter 3 (OAT-3), MCT-1 and LAT-1, and reduced expression of AP, CRT and P-gp by the BNB cell line at passage 20. Further studies demonstrated lower transendothelial electrical resistance (TEER: ~181 Ω.cm2 vs. 191 Ω.cm2), equivalent permeability to fluoresceinated sodium (4.84% vs. 4.39%) and lower permeability to fluoresceinated high molecular weight (70 kDa) dextran (0.39% vs. 0.52%) by the BNB cell line. This cell line retained essential molecular and biophysical properties suitable for in vitro peripheral nerve permeability studies. PMID:23104242

  10. Mechanisms of lymphocyte adhesion to endothelial cells: studies using a LFA-1-deficient cell line.

    PubMed Central

    Haskard, D O; Strobel, S; Thornhill, M; Pitzalis, C; Levinsky, R J

    1989-01-01

    In order to investigate the role of lymphocyte function-associated antigen 1 (LFA-1) in lymphocyte adhesion to endothelial cells (EC), we have studied the adhesion of a LFA-1-deficient lymphoblastoid cell line, ICH-KM, which has < 10% of the cell surface LFA-1 expressed on a normal lymphoblastoid cell line, ICH-BJ. The adhesion of ICH-KM cells to unstimulated EC was 49.9 +/- 8.6% (mean +/- SD) that of ICH-BJ cells. Moreover, phorbol ester-stimulated ICH-KM cells showed a considerably weaker increase in adhesion to unstimulated EC compared with ICH-BJ cells (mean +/- SD increase in percentage adhesion, 3.8 +/- 2.3 compared with 18.5 +/- 8.0; P<0.025). In contrast, there was no significant difference between the enhanced adhesion of ICH-KM cells and ICH-BJ cells to interleukin-1 (IL-1)-stimulated EC. Thus ICH-KM cells showed a 22.7 +/- 11.0 (mean +/- SD) increase in percentage adhesion to IL-1-stimulated EC compared with the 24.8 +/- 8.5 increase in percentage adhesion of ICH-BJ cells. Anti-LFA-1 monoclonal antibodies had no effect on the enhanced adhesion of ICH-KM and ICH-BJ cells to IL-1-stimulated EC but abolished the differences in adhesion between the two cell lines. The study therefore indicates that although a major part of unstimulated and phorbol ester-stimulated lymphocyte-EC adhesion is dependent upon LFA-1, the enhanced adhesion due to stimulation of EC with IL-1 is not dependent upon this molecule. The data therefore supports the existence of cytokine-inducible LFA-1-independent adhesion molecules for lymphocytes on EC. PMID:15493272

  11. Impact of intense pulsed light irradiation on cultured primary fibroblasts and a vascular endothelial cell line

    PubMed Central

    WU, DI; ZHOU, BINGRONG; XU, YANG; YIN, ZHIQIANG; LUO, DAN

    2012-01-01

    The aim of this study was to determine the effects of intense pulsed light (IPL) on cell proliferation and the secretion of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) in human fibroblasts and vascular endothelial cell lines, and to investigate the effects of IPL on the mRNA expression levels of type I and III procollagens in cultured human fibroblasts. Foreskin fibroblasts and a vascular endothelial cell line (ECV034) were cultured and treated with various wavelengths and doses of IPL irradiation. After culture for 1, 12, 24 and 48 h following IPL irradiation, fibroblasts and the vascular endothelial cell line were harvested for investigation of morphological changes by light microscopy, cell proliferation viability by MTT assay, and VEGF and MMP secretions by ELISA. The mRNA expression levels of type I and III procollagens in the fibroblasts were detected by RT-PCR. No marked morphological changes were observed in the cultured fibroblasts compared with the control. Cell growth and cellular viability were increased in fibroblasts 24 and 48 h after IPL irradiation. The levels of type I and III procollagen mRNA expression in fibroblasts increased in a time-dependent manner. However, the IPL management had no impact on VEGF and MMP secretion levels in fibroblasts and the ECV034 cell line at any time-point after irradiation as well as cell morphology and cellular proliferation. IPL irradiation may induce cellular proliferation and promote the expression of procollagen mRNAs directly in cultured primary fibroblasts, which may primarily contribute to photorejuvenation. PMID:23170124

  12. Modifications in astrocyte morphology and calcium signaling induced by a brain capillary endothelial cell line.

    PubMed

    Yoder, Elizabeth J

    2002-04-15

    Astrocytes extend specialized endfoot processes to perisynaptic and perivascular regions, and thus are positioned to mediate the bidirectional flow of metabolic, ionic, and other transmissive substances between neurons and the blood stream. While mutual structural and functional interactions between neurons and astrocytes have been documented, less is known about the interactions between astrocytes and cerebrovascular cells. For example, although the ability of astrocytes to induce structural and functional changes in endothelial cells is established, the reciprocity of brain endothelial cells to induce changes in astrocytes is undetermined. This issue is addressed in the present study. Changes in primary cultures of neonatal mouse cortical astrocytes were investigated following their coculture with mouse brain capillary endothelial (bEnd3) cells. The presence of bEnd3 cells altered the morphology of astrocytes by transforming them from confluent monolayers into networks of elongated multicellular columns. These columns did not occur when either bEnd3 cells or astrocytes were cocultured with other cell types, suggesting that astrocytes undergo specific morphological consequences when placed in close proximity to brain endothelial cells. In addition to these structural changes, the pharmacological profile of astrocytes was modified by coculture with bEnd3 cells. Astrocytes in the cocultures showed an increased Ca2+ responsiveness to bradykinin and glutamate, but no change in responsiveness to ATP, as compared to controls. Coculturing the astrocytes with a neuronal cell line resulted in increased responsiveness of the glial responses to glutamate but not to bradykinin. These studies indicate that brain endothelial cells induce changes in astrocyte morphology and pharmacology. PMID:11948807

  13. Effects of phthalates on the human corneal endothelial cell line B4G12.

    PubMed

    Krüger, Tanja; Cao, Yi; Kjærgaard, Søren K; Knudsen, Lisbeth E; Bonefeld-Jørgensen, Eva C

    2012-01-01

    Phthalates are industrial chemicals used in many cosmetics. We evaluated an in vitro model for eye irritancy testing using the human corneal endothelial cell line B4G12. Cell proliferation and toxicity were assessed after exposing to di-n-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), diisodecyl phthalate (DIDP), di-n-octyl phthalate (DnOP), and di-isononyl phthalate (DINP). Gene expression and secretion of inflammatory cytokines were evaluated after exposure to DBP. Decreased cell proliferation was observed for the phthalates DBP, BBP, and DEHP, and cell toxicity was observed for DBP and BBP. Upon DBP exposure at nontoxic concentrations, a significant increased gene expression and cytokine cell secretion were observed for interleukin-1β (IL-1β) and IL-8, and also an increased IL-6 secretion was observed. In conclusion, the human corneal endothelial cell line B4G12 may be a potential model for inflammatory eye irritancy testing of phthalates. PMID:22723514

  14. Generation of a Felinized Swine Endothelial Cell Line by Expression of Feline Decay-Accelerating Factor

    PubMed Central

    Izuhara, Luna; Tatsumi, Norifumi; Miyagawa, Shuji; Iwai, Satomi; Watanabe, Masahito; Yamanaka, Shuichiro; Katsuoka, Yuichi; Nagashima, Hiroshi; Okano, Hirotaka J.; Yokoo, Takashi

    2015-01-01

    Embryonic stem cell research has facilitated the generation of many cell types for the production of tissues and organs for both humans and companion animals. Because ≥30% of pet cats suffer from chronic kidney disease (CKD), xenotransplantation between pigs and cats has been studied. For a successful pig to cat xenotransplant, the immune reaction must be overcome, especially hyperacute rejection. In this study, we isolated the gene for feline decay-accelerating factor (fDAF), an inhibitor of complement proteins, and transfected a swine endothelial cell line with fDAF to “felinize” the pig cells. These fDAF-expressing cells were resistant to feline serum containing anti-pig antibodies, suggesting that felinized pig cells were resistant to hyperacute rejection. Our results suggest that a “felinized” pig kidney can be generated for the treatment of CKD in cats in the future. PMID:25671605

  15. Generation of a felinized swine endothelial cell line by expression of feline decay-accelerating factor.

    PubMed

    Izuhara, Luna; Tatsumi, Norifumi; Miyagawa, Shuji; Iwai, Satomi; Watanabe, Masahito; Yamanaka, Shuichiro; Katsuoka, Yuichi; Nagashima, Hiroshi; Okano, Hirotaka J; Yokoo, Takashi

    2015-01-01

    Embryonic stem cell research has facilitated the generation of many cell types for the production of tissues and organs for both humans and companion animals. Because ≥30% of pet cats suffer from chronic kidney disease (CKD), xenotransplantation between pigs and cats has been studied. For a successful pig to cat xenotransplant, the immune reaction must be overcome, especially hyperacute rejection. In this study, we isolated the gene for feline decay-accelerating factor (fDAF), an inhibitor of complement proteins, and transfected a swine endothelial cell line with fDAF to "felinize" the pig cells. These fDAF-expressing cells were resistant to feline serum containing anti-pig antibodies, suggesting that felinized pig cells were resistant to hyperacute rejection. Our results suggest that a "felinized" pig kidney can be generated for the treatment of CKD in cats in the future. PMID:25671605

  16. Physical View on the Interactions Between Cancer Cells and the Endothelial Cell Lining During Cancer Cell Transmigration and Invasion

    NASA Astrophysics Data System (ADS)

    Mierke, Claudia T.

    There exist many reviews on the biological and biochemical interactions of cancer cells and endothelial cells during the transmigration and tissue invasion of cancer cells. For the malignant progression of cancer, the ability to metastasize is a prerequisite. In particular, this means that certain cancer cells possess the property to migrate through the endothelial lining into blood or lymph vessels, and are possibly able to transmigrate through the endothelial lining into the connective tissue and follow up their invasion path in the targeted tissue. On the molecular and biochemical level the transmigration and invasion steps are well-defined, but these signal transduction pathways are not yet clear and less understood in regards to the biophysical aspects of these processes. To functionally characterize the malignant transformation of neoplasms and subsequently reveal the underlying pathway(s) and cellular properties, which help cancer cells to facilitate cancer progression, the biomechanical properties of cancer cells and their microenvironment come into focus in the physics-of-cancer driven view on the metastasis process of cancers. Hallmarks for cancer progression have been proposed, but they still lack the inclusion of specific biomechanical properties of cancer cells and interacting surrounding endothelial cells of blood or lymph vessels. As a cancer cell is embedded in a special environment, the mechanical properties of the extracellular matrix also cannot be neglected. Therefore, in this review it is proposed that a novel hallmark of cancer that is still elusive in classical tumor biological reviews should be included, dealing with the aspect of physics in cancer disease such as the natural selection of an aggressive (highly invasive) subtype of cancer cells displaying a certain adhesion or chemokine receptor on their cell surface. Today, the physical aspects can be analyzed by using state-of-the-art biophysical methods. Thus, this review will present

  17. Physical View on the Interactions Between Cancer Cells and the Endothelial Cell Lining During Cancer Cell Transmigration and Invasion

    NASA Astrophysics Data System (ADS)

    Mierke, Claudia T.

    2015-10-01

    There exist many reviews on the biological and biochemical interactions of cancer cells and endothelial cells during the transmigration and tissue invasion of cancer cells. For the malignant progression of cancer, the ability to metastasize is a prerequisite. In particular, this means that certain cancer cells possess the property to migrate through the endothelial lining into blood or lymph vessels, and are possibly able to transmigrate through the endothelial lining into the connective tissue and follow up their invasion path in the targeted tissue. On the molecular and biochemical level the transmigration and invasion steps are well-defined, but these signal transduction pathways are not yet clear and less understood in regards to the biophysical aspects of these processes. To functionally characterize the malignant transformation of neoplasms and subsequently reveal the underlying pathway(s) and cellular properties, which help cancer cells to facilitate cancer progression, the biomechanical properties of cancer cells and their microenvironment come into focus in the physics-of-cancer driven view on the metastasis process of cancers. Hallmarks for cancer progression have been proposed, but they still lack the inclusion of specific biomechanical properties of cancer cells and interacting surrounding endothelial cells of blood or lymph vessels. As a cancer cell is embedded in a special environment, the mechanical properties of the extracellular matrix also cannot be neglected. Therefore, in this review it is proposed that a novel hallmark of cancer that is still elusive in classical tumor biological reviews should be included, dealing with the aspect of physics in cancer disease such as the natural selection of an aggressive (highly invasive) subtype of cancer cells displaying a certain adhesion or chemokine receptor on their cell surface. Today, the physical aspects can be analyzed by using state-of-the-art biophysical methods. Thus, this review will present

  18. Degradation of endothelial basement membrane by human breast cancer cell lines

    SciTech Connect

    Yee, C.; Shiu, R.P.

    1986-04-01

    During metastasis, it is believed that tumor cells destroy the basement membrane (BM) of blood vessels in order to disseminate through the circulatory system. By radioactively labeling the extracellular matrix produced by primary endothelial cells in vitro, the ability of human breast cancer cells to degrade BM components was studied. We found that T-47D, a human breast cancer line, was able to degrade significant amounts of (35S)methionine-labeled and (3H)proline-labeled BM, but not 35SO4-labeled BM. Six other tumor cell lines of human breast origin were assayed in the same manner and were found to degrade BM to varying degrees. Several non-tumor cell lines tested showed relatively little degrading activity. The use of serum-free medium greatly enhanced degradation of the BM by tumor cells, suggesting a role for naturally occurring enzyme inhibitors in the serum. Direct cell contact with the BM was required for BM degradation, suggesting that the active enzymes are cell associated. The addition of hormones implicated in the etiology of breast cancer did not significantly alter the ability of T-47D cells to degrade the BM. The use of this assay affords future studies on the mechanism of invasion and metastasis of human breast cancer.

  19. Generation and characterization of feline arterial and venous endothelial cell lines for the study of the vascular endothelium

    PubMed Central

    2013-01-01

    Background The in vitro culture of endothelial cells (ECs) is an indispensable tool for studying the role of the endothelium in physical and pathological conditions. Primary ECs, however, have a restricted proliferative lifespan which hampers their use in long-term studies. The need for standardized experimental conditions to obtain relevant and reproducible results has increased the demand for well-characterized, continuous EC lines that retain the phenotypic and functional characteristics of their non-transformed counterparts. Results Primary feline ECs from aorta and vena cava were successfully immortalized through the successive introduction of simian virus 40 large T (SV40LT) antigen and the catalytic subunit of human telomerase (hTERT). In contrast to the parental ECs, the transformed cells were able to proliferate continuously in culture. Established cell lines exhibited several inherent endothelial properties, including typical cobblestone morphology, binding of endothelial cell-specific lectins and internalization of acetylated low-density lipoprotein. In addition, the immortalization did not affect the functional phenotype as demonstrated by their capacity to rapidly form cord-like structures on matrigel and to express cell adhesion molecules following cytokine stimulation. Conclusion The ability to immortalize feline ECs, and the fact that these cells maintain the EC phenotype will enable a greater understanding of fundamental mechanisms of EC biology and endothelial-related diseases. Furthermore, the use of cell lines is an effective implementation of the 3-R principles formulated by Russel and Burch. PMID:23987139

  20. Engineering anastomosis between living capillary networks and endothelial cell-lined microfluidic channels.

    PubMed

    Wang, Xiaolin; Phan, Duc T T; Sobrino, Agua; George, Steven C; Hughes, Christopher C W; Lee, Abraham P

    2016-01-21

    This paper reports a method for generating an intact and perfusable microvascular network that connects to microfluidic channels without appreciable leakage. This platform incorporates different stages of vascular development including vasculogenesis, endothelial cell (EC) lining, sprouting angiogenesis, and anastomosis in sequential order. After formation of a capillary network inside the tissue chamber via vasculogenesis, the adjacent microfluidic channels are lined with a monolayer of ECs, which then serve as the high-pressure input ("artery") and low pressure output ("vein") conduits. To promote a tight interconnection between the artery/vein and the capillary network, sprouting angiogenesis is induced, which promotes anastomosis of the vasculature inside the tissue chamber with the EC lining along the microfluidic channels. Flow of fluorescent microparticles confirms the perfusability of the lumenized microvascular network, and minimal leakage of 70 kDa FITC-dextran confirms physiologic tightness of the EC junctions and completeness of the interconnections between artery/vein and the capillary network. This versatile device design and its robust construction methodology establish a physiological transport model of interconnected perfused vessels from artery to vascularized tissue to vein. The system has utility in a wide range of organ-on-a-chip applications as it enables the physiological vascular interconnection of multiple on-chip tissue constructs that can serve as disease models for drug screening. PMID:26616908

  1. Cell death induced by Bothrops asper snake venom metalloproteinase on endothelial and other cell lines.

    PubMed

    Brenes, Oscar; Muñóz, Eduardo; Roldán-Rodríguez, Raquel; Díaz, Cecilia

    2010-06-01

    Two adherent cell lines, BAEC and HeLa, and non-adherent Jurkat, were treated with snake venom metalloproteinase BaP1 to determine whether cytotoxicity, previously reported for this toxin, could be mediated by the process of anoikis. It was observed that there was no correlation between the ability of this toxin to induce loss of adherence, and the cytotoxic effect, since concentrations that do not induce loss of adherence (3-6 microg/mL), were able to trigger 50% of cytotoxicity in BAEC. In the case of HeLa, where toxicity was very low (less than 20% at maximun concentrations and times of exposure), significant detachment and no toxicity was observed at concentrations of 1.5 microg/mL, showing also no correlation between both events. We also observed differences between BAEC toxicity measured by XTT reduction and DNA fragmentation determined by flow cytometry (as an indicator of apoptosis), since concentrations that induce 100% of cytotoxicity barely showed any DNA fragmentation (12% at 24h), suggesting that if apoptosis was involved, DNA damage is still not present, although chromatin condensation, another indicator of apoptosis, is observed in 40% of the cells. Inhibition of BAEC cytotoxicity by caspase inhibitors indicate that apoptosis is playing a role in this process, but other mechanisms of cell death could be participating also. Another way to determine whether the mechanism of cell death was related to anoikis was using a non-adherent cell line, which should show substrate independence. We determined by TUNEL that at 50 microg/ml BaP1 triggered 50% of apoptosis at 96 h, an effect that was seen earlier, suggesting also that if this toxin was inducing apoptosis in a non-adherent cell line, the mechanism could not be related to loss of attachment. Cell cycle arrest in S phase was also observed in Jurkat cells, an effect that could be leading to apoptosis. In conclusion, since there was no correlation between cell detachment and cytotoxicity (and apoptosis

  2. Immortalized Functional Endothelial Progenitor Cell Lines from Umbilical Cord Blood for Vascular Tissue Engineering

    PubMed Central

    Sobhan, Praveen K.; Seervi, Mahendra; Joseph, Jeena; Varghese, Saneesh; Pillai, Prakash Rajappan; Sivaraman, Divya Mundackal; James, Jackson; George, Roshin Elizabeth; Elizabeth, K.E.; Pillai, M. Radhakrishna

    2012-01-01

    Endothelial progenitor cells (EPCs) play a significant role in multiple biological processes such as vascular homeostasis, regeneration, and tumor angiogenesis. This makes them a promising cell of choice for studying a variety of biological processes, toxicity assays, biomaterial–cell interaction studies, as well as in tissue-engineering applications. In this study, we report the generation of two clones of SV40-immortalized EPCs from umbilical cord blood. These cells retained most of the functional features of mature endothelial cells and showed no indication of senescence after repeated culture for more than 240 days. Extensive functional characterization of the immortalized cells by western blot, flow cytometry, and immunofluorescence studies substantiated that these cells retained their ability to synthesize nitric oxide, von Willebrand factor, P-Selectin etc. These cells achieved unlimited proliferation potential subsequent to inactivation of the cyclin-dependent kinase inhibitor p21, but failed to form colonies on soft agar. We also show their enhanced growth and survival on vascular biomaterials compared to parental cultures in late population doubling. These immortalized EPCs can be used as a cellular model system for studying the biology of these cells, gene manipulation experiments, cell–biomaterial interactions, as well as a variety of tissue-engineering applications. PMID:22889128

  3. Effects of autocrine vascular endothelial growth factor (VEGF) in non-small cell lung cancer cell line A549.

    PubMed

    Wang, Ying; Huang, Lu; Yang, Yunmei; Xu, Liqian; Yang, Ji; Wu, Yue

    2013-04-01

    It is reported that the autocrine loop of the vascular endothelial growth factor (VEGF) is crucial for the survival and proliferation of non-small cell lung cancer (NSCLC) tumors. In this study we aimed to systematically investigate the role of autocrine vascular VEGF in NSCLC cell line A549 through inhibition of endogenous VEGF. A549 cells were transfected with florescence-labeled VEGF oligodeoxynucleotide with lipofectamine. For the experimental group, cells were transfected with VEGF anti-sense oligodeoxynucleotide (ASODN), sense oligodeoxynucleotide (SODN) and mutant oligodeoxynuleotide (MODN) respectively. For the control group cells were mock transfected with lipofectamine or culture medium. At indicated time point after transfection, the expression levels of VEGF mRNA and protein in A549 cells were analyzed by RT-PCR and ELISA respectively. Cell viability was measured by the MTT assay. Cell cycle distribution was detected by flow cytometry. As revealed by RT-PCR assay, the mRNA level of VEGF in cells transfected with ASDON was significantly lower than the other four groups (P < 0.05) at 24 and 48 h after transfection. ELISA assay yielded similar result with significantly decreased level of VEGF protein expression (P < 0.05). The survival fraction of A549 cells transfected with ASDON was significantly lower than the other four groups (P < 0.05) at 24 h after transfection. Also the percentage of G2 phase cells of ASODN group was significantly lower than other four groups. Our data indicate that VEGF expression is efficiently inhibited in A549 cells by ASODN transfection and this inhibition leads to inhibited cell growth and impaired cell cycle distribution. PMID:23459872

  4. Biological effects of simulated microgravity on human umbilical vein endothelial cell line HUVEC-C

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Cheng, Zhenlong; Liang, Shujian; Sun, Yeqing

    Microgravity has been reported to have multiple influences on human cells. To investigate the biological effects of simulated microgravity on human endothelial cells, human umbilical vein endothelial cell HUVEC-C was treated with microgravity for 24 hours and restored at 1 g gravity for extra 24 hours (group 1) and 48 hours and restored for 24 hours (group 2). Microgravity was simulated by using a two-dimensionally rotating clinostat, set on 30 rpm. As controls, cells were cultured paralleled at 1 g gravity. Two groups of treated cells and control cells were harvested at 0, 12, 24, 48 and 72 (for group 2 and control only) hours for proliferation, cell cycles, apoptosis, proteome and microarray analysis. The influences of microgravity on cell proliferation were controversial in previous reports, and in our experiment, inhibitory effect was observed at 12 hour, and cell number of the treatment groups presented 9.26% decrease compared with that of control. Cell cycle distribution was analyzed using flow cytometry. The G2/M cell cycle arrest also occurred at 12 hour in both treatment groups, the cell rates at G2/M phase were 24% higher than in control. Effect of simulated microgravity on cell apoptosis was observed only after 48-hour-treatment, resulted in percentage of apoptotic cells increased by 53-67% compared with control. After cells returned to normal conditions for 24 hours, levels of cell proliferation, cell cycle and cell apoptosis in treatment groups were comparable to control. In order to investigate the molecular mechanism, we analyzed the treated cells at proteomic and transcriptomic levels respectively. Two-dimensional electrophoresis showed that after 24- hour-restoration under normal conditions, 189 proteins in control group disappeared and 187 new proteins presented in group 1; 469 proteins disappeared and 291 new proteins presented in group 2. By using microarray, we found that expression levels of 56 genes were up-regulated and 45 down-regulated in

  5. In Vitro Endothelialization Test of Biomaterials Using Immortalized Endothelial Cells

    PubMed Central

    Kono, Ken; Hiruma, Hitomi; Kobayashi, Shingo; Sato, Yoji; Tanaka, Masaru; Sawada, Rumi; Niimi, Shingo

    2016-01-01

    Functionalizing biomaterials with peptides or polymers that enhance recruitment of endothelial cells (ECs) can reduce blood coagulation and thrombosis. To assess endothelialization of materials in vitro, primary ECs are generally used, although the characteristics of these cells vary among the donors and change with time in culture. Recently, primary cell lines immortalized by transduction of simian vacuolating virus 40 large T antigen or human telomerase reverse transcriptase have been developed. To determine whether immortalized ECs can substitute for primary ECs in material testing, we investigated endothelialization on biocompatible polymers using three lots of primary human umbilical vein endothelial cells (HUVEC) and immortalized microvascular ECs, TIME-GFP. Attachment to and growth on polymer surfaces were comparable between cell types, but results were more consistent with TIME-GFP. Our findings indicate that TIME-GFP is more suitable for in vitro endothelialization testing of biomaterials. PMID:27348615

  6. Assessment of electrophile damage in a human brain endothelial cell line utilizing a clickable alkyne analog of 2-chlorohexadecanal.

    PubMed

    Nusshold, Christoph; Üllen, Andreas; Kogelnik, Nora; Bernhart, Eva; Reicher, Helga; Plastira, Ioanna; Glasnov, Toma; Zangger, Klaus; Rechberger, Gerald; Kollroser, Manfred; Fauler, Günter; Wolinski, Heimo; Weksler, Babette B; Romero, Ignacio A; Kohlwein, Sepp D; Couraud, Pierre-Olivier; Malle, Ernst; Sattler, Wolfgang

    2016-01-01

    Peripheral leukocytes aggravate brain damage by releasing cytotoxic mediators that compromise blood-brain barrier function. One of the oxidants released by activated leukocytes is hypochlorous acid (HOCl) that is formed via the myeloperoxidase-H2O2-chloride system. The reaction of HOCl with the endogenous plasmalogen pool of brain endothelial cells results in the generation of 2-chlorohexadecanal (2-ClHDA), a toxic, lipid-derived electrophile that induces blood-brain barrier dysfunction in vivo. Here, we synthesized an alkynyl-analog of 2-ClHDA, 2-chlorohexadec-15-yn-1-al (2-ClHDyA) to identify potential protein targets in the human brain endothelial cell line hCMEC/D3. Similar to 2-ClHDA, 2-ClHDyA administration reduced cell viability/metabolic activity, induced processing of pro-caspase-3 and PARP, and led to endothelial barrier dysfunction at low micromolar concentrations. Protein-2-ClHDyA adducts were fluorescently labeled with tetramethylrhodamine azide (N3-TAMRA) by 1,3-dipolar cycloaddition in situ, which unveiled a preferential accumulation of 2-ClHDyA adducts in mitochondria, the Golgi, endoplasmic reticulum, and endosomes. Thirty-three proteins that are subject to 2-ClHDyA-modification in hCMEC/D3 cells were identified by mass spectrometry. Identified proteins include cytoskeletal components that are central to tight junction patterning, metabolic enzymes, induction of the oxidative stress response, and electrophile damage to the caveolar/endosomal Rab machinery. A subset of the targets was validated by a combination of N3-TAMRA click chemistry and specific antibodies by fluorescence microscopy. This novel alkyne analog is a valuable chemical tool to identify cellular organelles and protein targets of 2-ClHDA-mediated damage in settings where myeloperoxidase-derived oxidants may play a disease-propagating role. PMID:26577177

  7. Photodynamic treatment with zinc poly-substituted phthalocyanines causes the release of tissue factor in an endothelial cell line

    NASA Astrophysics Data System (ADS)

    Cruse-Sawyer, Janet E.; Dixon, B.; Griffiths, John; Brown, Stanley B.

    1996-12-01

    Tissue factor (TF) is not expressed by endothelial cells unless they have ben perturbed. Identifying the extrinsic pathway of coagulation as the process involved in clot formation demonstrated that PDT induces release of TF by endothelial cells. EAhy 926 cells were incubated with 10 (mu) g ml-1 of photosensitizer for 24 h prior to illumination at 40 J cm-2. A clotting assay was then performed. PDT caused a significant reduction in clotting time. This was repeated using factor VII- or X-deficient serum. In factor VII-deficient serum there was no difference between treated and untreated cells. There was no clot formation with any cells in the presence of factor x- deficient serum. The data indicate that PDT-induced procoagulation activity is via the extrinsic pathway of coagulation and results from direct initiation of endothelial cells to release tissue factor.

  8. Effects of glucose on collagen mRNA levels and collagen secretion in EAhy 926 endothelial cell line.

    PubMed

    Kössi, J; Muona, P; Tuukkanen, J; Ylä-Outinen, H; Kalliomäki, M; Risteli, J; Oikarinen, A; Laato, M; Peltonen, J

    2001-01-01

    Diabetes mellitus (DM) is a complex metabolic disease associated with increased accumulation of extracellular matrix by endothelial cells and contributing to vascular complications of long-standing diabetes. On the other hand, DM is also associated with decreased accumulation of extracellular matrix in granulation tissue, which is suggested to be a consequence of impaired angiogenesis. The role of hyperglycemia in these situations is not fully understood. We examined the effects of high glucose concentrations on the gene expression and secretion of various collagens in cultured EAhy 926 endothelial cells. EAhy 926 endothelial cells expressed alpha1(I) collagen mRNA at a low level and small amount of the corresponding peptide was secreted from the cells; mRNA was not affected but peptide secretion was increased by elevated glucose concentration. mRNAs for type III and VI collagens were not detected in the endothelial cells. Furthermore, high glucose concentration in long term had no morphological effects on cultured endothelial cells but increased the expression of type IV collagen, which could rather be beneficial for angiogenesis in a healing wound. Our results suggest that high glucose concentration per se may contribute to increased accumulation of extracellular matrix in blood vessels but probably is not responsible for decreased angiogenesis and granulation tissue formation in diabetic patients. PMID:12041927

  9. Effects of glucose on collagen mRNA levels and collagen secretion in EAhy 926 endothelial cell line.

    PubMed

    Kössi, J; Muona, P; Tuukkanen, J; Ylä-Outinen, H; Kalliomäki, M; Risteli, J; Oikarinen, A; Laato, M; Peltonen, J

    2001-01-01

    Diabetes mellitus (DM) is a complex metabolic disease associated with increased accumulation of extracellular matrix by endothelial cells and contributing to vascular complications of long-standing diabetes. On the other hand, DM is also associated with decreased accumulation of extracellular matrix in granulation tissue, which is suggested to be a consequence of impaired angiogenesis. The role of hyperglycemia in these situations is not fully understood. We examined the effects of high glucose concentrations on the gene expression and secretion of various collagens in cultured EAhy 926 endothelial cells. EAhy 926 endothelial cells expressed alpha 1(I) collagen mRNA at a low level and small amount of the corresponding peptide was secreted from the cells; mRNA was not affected but peptide secretion was increased by elevated glucose concentration. mRNAs for type III and VI collagens were not detected in the endothelial cells Furthermore, high glucose concentration in long term had no morphological effects on cultured endothelial cells but increased the expression of type IV collagen, which could rather be beneficial for angiogenesis in a healing wound. Our results suggest that high glucose concentration per se may contribute to increased accumulation of extracellular matrix in blood vessels but probably is not responsible for decreased angiogenesis and granulation tissue formation in diabetic patients. PMID:12016747

  10. Characterisation of a mouse cerebral microvascular endothelial cell line (bEnd.3) after oxygen glucose deprivation and reoxygenation.

    PubMed

    Ku, Jacqueline M; Taher, Mohammadali; Chin, Kai Yee; Grace, Megan; McIntyre, Peter; Miller, Alyson A

    2016-08-01

    Studies have utilised immortalised mouse cerebral endothelial cells (bEnd.3) exposed to oxygen glucose deprivation (OGD) to study blood-brain barrier (BBB) disruption after ischaemia. However, there is a paucity of literature describing the duration of OGD (and reoxygenation [RO]) required to best simulate BBB disruption in vivo. In this study we assessed BBB disruption in bEnd.3 cells after exposure to a range of OGD periods, and also after OGD + RO. Exposure of bEnd.3 monolayers to 4, 6, 16, or 24 hours of OGD resulted in a significant increase in permeability. The hyperpermeability after 16 or 24 hours was associated with decreased expression of tight junction proteins (occludin and claudin-5). Furthermore, there was a decrease in cell viability and increased expression of the pro-apoptotic protein, cleaved caspase-3. Exposure of bEnd.3 monolayers to 1 hour OGD+ 23 hours RO exacerbated hyperpermeability relative to 1 hour OGD, which was associated with decreased expression levels of occludin and ZO-1, but no change in cell viability or caspase-3. 4 hours OGD + 23 hours RO exacerbated hyperpermeability, decreased expression levels of tight junction proteins, decreased cell viability, and increased caspase-3 expression. Thus, bEnd.3 cells exhibit hyperpermeability, a loss of tight junction proteins, and undergo cell death, after exposure to prolonged periods of OGD. Moreover, they exhibit exacerbated hyperpermeability, a loss of tight junction proteins, and increased expression of caspase-3 after OGD + RO. These findings will facilitate the use of this cell line in studies of BBB disruption and for the testing of therapeutics. PMID:27128638

  11. Quantitation of Endothelial Cell Adhesiveness In Vitro

    PubMed Central

    Lowe, Donna J.; Raj, Kenneth

    2015-01-01

    One of the cardinal processes of inflammation is the infiltration of immune cells from the lumen of the blood vessel to the surrounding tissue. This occurs when endothelial cells, which line blood vessels, become adhesive to circulating immune cells such as monocytes. In vitro measurement of this adhesiveness has until now been done by quantifying the total number of monocytes that adhere to an endothelial layer either as a direct count or by indirect measurement of the fluorescence of adherent monocytes. While such measurements do indicate the average adhesiveness of the endothelial cell population, they are confounded by a number of factors, such as cell number, and do not reveal the proportion of endothelial cells that are actually adhesive. Here we describe and demonstrate a method which allows the enumeration of adhesive cells within a tested population of endothelial monolayer. Endothelial cells are grown on glass coverslips and following desired treatment are challenged with monocytes (that may be fluorescently labeled). After incubation, a rinsing procedure, involving multiple rounds of immersion and draining, the cells are fixed. Adhesive endothelial cells, which are surrounded by monocytes are readily identified and enumerated, giving an adhesion index that reveals the actual proportion of endothelial cells within the population that are adhesive. PMID:26132714

  12. Human Brain Microvascular Endothelial Cells Derived from the BC1 iPS Cell Line Exhibit a Blood-Brain Barrier Phenotype

    PubMed Central

    Gerecht, Sharon; Searson, Peter C.

    2016-01-01

    The endothelial cells that form capillaries in the brain are highly specialized, with tight junctions that minimize paracellular transport and an array of broad-spectrum efflux pumps that make drug delivery to the brain extremely challenging. One of the major limitations in blood-brain barrier research and the development of drugs to treat central nervous system diseases is the lack of appropriate cell lines. Recent reports indicate that the derivation of human brain microvascular endothelial cells (hBMECs) from human induced pluripotent stem cells (iPSCs) may provide a solution to this problem. Here we demonstrate the derivation of hBMECs extended to two new human iPSC lines: BC1 and GFP-labeled BC1. These hBMECs highly express adherens and tight junction proteins VE-cadherin, ZO-1, occludin, and claudin-5. The addition of retinoic acid upregulates VE-cadherin expression, and results in a significant increase in transendothelial electrical resistance to physiological values. The permeabilities of tacrine, rhodamine 123, and Lucifer yellow are similar to values obtained for MDCK cells. The efflux ratio for rhodamine 123 across hBMECs is in the range 2–4 indicating polarization of efflux transporters. Using the rod assay to assess cell organization in small vessels and capillaries, we show that hBMECs resist elongation with decreasing diameter but show progressive axial alignment. The derivation of hBMECs with a blood-brain barrier phenotype from the BC1 cell line highlights that the protocol is robust. The expression of GFP in hBMECs derived from the BC1-GFP cell line provides an important new resource for BBB research. PMID:27070801

  13. Human Brain Microvascular Endothelial Cells Derived from the BC1 iPS Cell Line Exhibit a Blood-Brain Barrier Phenotype.

    PubMed

    Katt, Moriah E; Xu, Zinnia S; Gerecht, Sharon; Searson, Peter C

    2016-01-01

    The endothelial cells that form capillaries in the brain are highly specialized, with tight junctions that minimize paracellular transport and an array of broad-spectrum efflux pumps that make drug delivery to the brain extremely challenging. One of the major limitations in blood-brain barrier research and the development of drugs to treat central nervous system diseases is the lack of appropriate cell lines. Recent reports indicate that the derivation of human brain microvascular endothelial cells (hBMECs) from human induced pluripotent stem cells (iPSCs) may provide a solution to this problem. Here we demonstrate the derivation of hBMECs extended to two new human iPSC lines: BC1 and GFP-labeled BC1. These hBMECs highly express adherens and tight junction proteins VE-cadherin, ZO-1, occludin, and claudin-5. The addition of retinoic acid upregulates VE-cadherin expression, and results in a significant increase in transendothelial electrical resistance to physiological values. The permeabilities of tacrine, rhodamine 123, and Lucifer yellow are similar to values obtained for MDCK cells. The efflux ratio for rhodamine 123 across hBMECs is in the range 2-4 indicating polarization of efflux transporters. Using the rod assay to assess cell organization in small vessels and capillaries, we show that hBMECs resist elongation with decreasing diameter but show progressive axial alignment. The derivation of hBMECs with a blood-brain barrier phenotype from the BC1 cell line highlights that the protocol is robust. The expression of GFP in hBMECs derived from the BC1-GFP cell line provides an important new resource for BBB research. PMID:27070801

  14. Real-time monitoring of cell mechanical changes induced by endothelial cell activation and their subsequent binding with leukemic cell lines.

    PubMed

    Tan, Liang; Lin, Peiling; Pezeshkian, Bahareh; Rehman, Abdul; Madlambayan, Gerard; Zeng, Xiangqun

    2014-06-15

    Endothelial cell (EC) activation and their subsequent binding with different cells have various mechanical consequences that, if monitored real time, can serve as a functional biomarker of many pathophysiological response mechanisms. This work presents an innovative and facile strategy to conduct such monitoring using quartz crystal microbalance (QCM), thereby relating the shifts in its frequency and motional resistance to morphological changes upon cell-cell and cell-substrate interactions. By activating ECs with TNF-α and then characterizing their binding with HL-60 and KG-1 leukemia cells, we are able to induce the mechanical changes in ECs especially in the region of cell-substrate contact which resulted in dynamically coupled mass and viscoelastic changes representing the extent of both activation and binding. The activated ECs suffered a decrease of cellular contact area, leading to positive frequency shift and decreased motional resistance. The binding of leukemia cells onto pre-activated ECs exerted a mechanical force to regain the cell surface contact which resulted in the obvious QCM responses opposite to that of activation, and proportional to the number of cells added, in spite of the fact that these added cells are extremely outside the extinction boundary of the shear wave generated by QCM. Different cell lines demonstrate different attachment behavior, which was detected by the QCM. Despite these variations are quite subtle, yet the sensitivity of the technique for dynamic changes at the interface makes them detectable. Moreover, the reproducibility of the generated data determined at each step by deviation measurements (<10%) in response plot was very high despite the high possible heterogeneity in cell populations. The results are explained on the basis of simple theoretical and physical models, although, the development of a more quantitative and precise model is underway in our laboratory. PMID:24487102

  15. Real-Time Monitoring of Cell Mechanical Changes Induced by Endothelial Cell Activation and their Subsequent Binding with Leukemic Cell Lines

    PubMed Central

    Tan, Liang; Lin, Peiling; Pezeshkian, Bahareh; Rehman, Abdul; Madlambayan, Gerard; Zeng, Xiangqun

    2014-01-01

    Endothelial cell (EC) activation and their subsequent binding with different cells have various mechanical consequences that, if monitored real time, can serve as a functional biomarker of many pathophysiological response mechanisms. This work presents an innovative and facile strategy to conduct such monitoring using quartz crystal microbalance (QCM), thereby relating the shifts in its frequency and motional resistance to morphological changes upon cell-cell and cell-substrate interactions. By activating ECs with TNF-α and then characterizing their binding with HL-60 and KG-1 leukemia cells, we are able to induce the mechanical changes in ECs especially in the region of cell-substrate contact which resulted in dynamically coupled mass and viscoelastic changes representing the extent of both activation and binding. The activated ECs suffered a decrease of cellular contact area, leading to positive frequency shift and decreased motional resistance. The binding of leukemia cells onto pre-activated ECs exerted a mechanical force to regain the cell surface contact which resulted in the obvious QCM responses opposite to that of activation, and proportional to the number of cells added, in spite of the fact that these added cells are extremely outside the extinction depth of the shear wave generated by QCM. Different cell lines demonstrate different attachment behavior, which was detected by the QCM. Despite these variations are quite subtle, yet the sensitivity of the technique for dynamic changes at the interface makes them detectable. Moreover, the reproducibility of the generated data determined at each step by deviation measurements (<10%) in response plot was very high despite the high possible heterogeneity in cell populations. The results are explained on the basis of simple theoretical and physical models, although, the development of a more quantitative and precise model is underway in our laboratory. PMID:24487102

  16. Cloning and Stable Expression of cDNA Coding For Platelet Endothelial Cell Adhesion Molecule -1 (PECAM-1, CD31) in NIH-3T3 Cell Line

    PubMed Central

    Salehi-Lalemarzi, Hamed; Shanehbandi, Dariush; Shafaghat, Farzaneh; Abbasi-Kenarsari, Hajar; Baradaran, Behzad; Movassaghpour, Ali Akbar; Kazemi, Tohid

    2015-01-01

    Purpose: PECAM-1 (CD31) is a glycoprotein expressed on endothelial and bone marrow precursor cells. It plays important roles in angiogenesis, maintenance and integration of the cytoskeleton and direction of leukocytes to the site of inflammation. We aimed to clone the cDNA coding for human CD31 from KG1a for further subcloning and expression in NIH-3T3 mouse cell line. Methods: CD31 cDNA was cloned from KG1a cell line after total RNA extraction and cDNA synthesis. Pfu DNA polymerase-amplified specific band was ligated to pGEMT-easy vector and sub-cloned in pCMV6-Neo expression vector. After transfection of NIH-3T3 cells using 3 μg of recombinant construct and 6 μl of JetPEI transfection reagent, stable expression was obtained by selection of cells by G418 antibiotic and confirmed by surface flow cytometry. Results: 2235 bp specific band was aligned completely to human CD31 reference sequence in NCBI database. Transient and stable expression of human CD31 on transfected NIH-3T3 mouse fibroblast cells was achieved (23% and 96%, respectively) as shown by flow cytometry. Conclusion: Due to murine origin of NIH-3T3 cell line, CD31-expressing NIH-3T3 cells could be useful as immunogen in production of diagnostic monoclonal antibodies against human CD31, with no need for purification of recombinant proteins. PMID:26236664

  17. Therapeutic Strategies for Patients With Metastatic Renal Cell Carcinoma in Whom First-Line Vascular Endothelial Growth Factor Receptor-Directed Therapies Fail.

    PubMed

    Malouf, Gabriel G; Flippot, Ronan; Khayat, David

    2016-05-01

    Metastases are present in one third of renal cell carcinomas at diagnosis. The overall survival duration in metastatic renal cell carcinoma is approximately 22 months, which underlines the need for more effective systemic treatments. Therapies on the basis of antiangiogenic agents and inhibitors of the mammalian target of rapamycin have been approved for treatment of metastatic renal cell carcinoma, but only benefits for progression-free survival were demonstrated in the second-line setting. Fortunately, promising treatments are emerging, from new antiangiogenic agents to immune checkpoint inhibitors. For the first time, both an immune checkpoint inhibitor (nivolumab) and a dual inhibitor of the tyrosine kinases c-Met and vascular endothelial growth factor receptor-2 (cabozantinib) have demonstrated improvements in overall survival in the second-line setting. Finding the best sequence for these novel agents will be crucial to improving outcomes in patients with metastatic renal cell carcinoma. This article comprises both a systematic review of the literature and recommendations for second-line therapeutic strategies for patients with metastatic clear cell renal cell carcinoma in whom inhibitors of vascular endothelial growth factor have failed. PMID:27170687

  18. Effects of Bisphosphonates on Glucose Transport in a Conditionally Immortalized Rat Retinal Capillary Endothelial Cell Line (TR-iBRB Cells)

    PubMed Central

    Lee, Na-Young; Park, Hyun-Joo; Kang, Young-Sook

    2016-01-01

    The objective of the present study was to elucidate the effect of bisphosphonates, anti-osteoporosis agents, on glucose uptake in retinal capillary endothelial cells under normal and high glucose conditions. The change of glucose uptake by pre-treatment of bisphosphonates at the inner blood-retinal barrier (iBRB) was determined by measuring cellular uptake of [3H]3-O-methyl glucose (3-OMG) using a conditionally immortalized rat retinal capillary endothelial cell line (TR-iBRB cells) under normal and high glucose conditions. [3H]3-OMG uptake was inhibited by simultaneous treatment of unlabeled D-glucose and 3-OMG as well as glucose transport inhibitor, cytochalasin B. On the other hand, simultaneous treatment of alendronate or pamidronate had no significant inhibitory effect on [3H]3-OMG uptake by TR-iBRB cells. Under high glucose condition of TR-iBRB cells, [3H]3-OMG uptake was increased at 48 h. However, [3H]3-OMG uptake was decreased significantly by pre-treatment of alendronate or pamidronate compared with the values for normal and high glucose conditions. Moreover, geranylgeraniol (GGOH), a mevalonate pathway intermediate, increased the uptake of [3H]3-OMG reduced by bisphosphonates pre-treatment. But, pre-treatment of histamine did not show significant inhibition of [3H]3-OMG uptake. The glucose uptake may be down regulated by inhibiting the mevalonate pathway with pre-treatment of bisphosphonates in TR-iBRB cells at high glucose condition. PMID:26759707

  19. Expression of angiostatin cDNA in human gallbladder carcinoma cell line GBC-SD and its effect on endothelial proliferation and growth

    PubMed Central

    Yang, Ding-Zhong; He, Jing; Zhang, Ji-Cheng; Wang, Zuo-Ren

    2006-01-01

    AIM: To explore the influence of angiostatin up-regulation on the biologic behavior of gallbladder carcinoma cells in vitro and in vitro, and the potential value of angiostatin gene therapy for gallbladder carcinoma. METHODS: A eukaryotic expression vector of pcDNA3.1(+) containing murine angiostatin was constructed and identified by restriction endonuclease digestion and sequencing. The recombinant vector pcDNA3.1-angiostatin was transfected into human gallbladder carcinoma cell line GBC-SD with Lipofectamine 2000, and paralleled with the vector and mock control. The resistant clone was screened by G418 filtration. Angiostatin transcription and protein expression were examined by RT-PCR, immunofluorescence and Western-blot. The supernatant was collected to treat endothelial cells. Cell proliferation and growth in vitro were observed under microscope. RESULTS: Murine angiostatin cDNA was successfully cloned into the eukaryotic expression vector pcDNA3.1 (+). After 14 d of transfection and selection with G418, macroscopic resistant cell cloning was formed in the experimental group transfected with pcDNA 3.1(+)-angiostatin and vector control. But untreated cells died in the mock control. Angiostatin was detected by RT-PCR and protein expression was detected in the experimental group by immunofluorescence and Western-blot. Cell proliferation and growth in vitro in the three groups were observed respectively under microscope. No significant difference was observed in the growth speed of GBC-SD cells between groups that were transfected with and without angiostatin. After treatment with supernatant, significant differences were observed in endothelial cell (ECV-304) growth in vitro. The cell proliferation and growth were inhibited. CONCLUSION: Angiostatin does not directly inhibit human gallbladder carcinoma cell proliferation and growth in vitro, but the secretion of angiostatin inhabits endothelial cell proliferation and growth. PMID:16718765

  20. Molecular cloning and expression of two distinct cDNA-encoding heparan sulfate proteoglycan core proteins from a rat endothelial cell line.

    PubMed

    Kojima, T; Shworak, N W; Rosenberg, R D

    1992-03-01

    The cloned rat fat pad endothelial cell (RFP-EC) line synthesizes anticoagulantly active heparan sulfate proteoglycans (HSPGact) and anticoagulantly inactive heparan sulfate proteoglycans (HSPGinact), both of which exhibit 25-, 30-, and 50-kDa core proteins of extremely similar structure. The primary sequences of internal peptides obtained from HSPGinact core proteins and the NH2-terminal sequence analyses of the 25-kDa component from the HSPGinact core proteins demonstrate that the 30-kDa component is a previously unidentified species, designated as ryudocan, with the 25-kDa component representing a proteolytic degradation product, while the 50-kDa component is the rat homolog of syndecan (Saunders, S. Jalkanen, M., O'Farrell, S., and Bernfield, M. (1989) J. Cell Biol. 108, 1547-1556). Specific oligonucleotide probes were obtained for ryudocan and syndecan by polymerase chain reaction, and the corresponding cDNAs were isolated from a RFP-EC library. The cDNAs encode type I integral membrane proteins of 202 and 313 amino acids, respectively, which have homologous transmembrane and intracellular domains but very distinct extracellular regions. In particular, ryudocan exhibits only three potential glycosaminoglycan attachment sites within the extracellular region while syndecan has five glycosaminoglycan attachment sites within the same domain. Both species are expressed in RFP-EC lines, primary rat aortic smooth muscle cells and primary rat skin fibroblast cells. The levels of ryudocan and syndecan mRNA were measured by quantitative polymerase chain reaction in primary microvascular endothelial cells and closely associated non-endothelial cells isolated by cell sorting. Ryudocan and syndecan mRNAs were abundantly expressed in both populations representing about 0.1-0.5% of mRNA. PMID:1537865

  1. Increased production of soluble vascular endothelial growth factors receptor-1 in CHO-cell line by using new combination of chitosan-protein lipid nanoparticles

    PubMed Central

    Farnia, Poopak; Ghanavi, Jalaledin; Bahrami, Afshin; Bandehpour, Mojgan; Kazemi, Bahram; Velayati, Ali Akbar

    2015-01-01

    The soluble vascular endothelial growth factor receptor-1 (VEGFR1) or sFLT-1 has important role in antiangiogenesis. In this study, the increase expression and production of sFLT-1 fragment by newly designed ChPL-NPs nanoparticles (chitosan-protein lipid) using Chinese hamster ovary cell line (CHO) was evaluated. The assessment and purification of sFLT-1 were carried out by western blotting and fast protein liquid chromatography (FPLC). Thereafter, the angiostatic effect of gene transfer of sFLT-1 in Human umbilical vein endothelial cell line (HUVEC) was evaluated. Our results showed a significance rate of transfection with ChPL-NPs (80-85%) in comparison to standard lipofectamine2000 (65-70%) (P < 0.05). The anti-angiogenic action of sFLT-1 was observed by in-vitro culture of recombinant protein (sFLT-1; 50 ng/ml) with HUVEC cell lines (5 × 106). The ChPL-NPs nanoparticles can consider a potential carrier system for large scale production of sFLT-1, which ultimately may be use as therapeutic agent in targeting solid tumor tissues. PMID:25785168

  2. Increased production of soluble vascular endothelial growth factors receptor-1 in CHO-cell line by using new combination of chitosan-protein lipid nanoparticles.

    PubMed

    Farnia, Poopak; Ghanavi, Jalaledin; Bahrami, Afshin; Bandehpour, Mojgan; Kazemi, Bahram; Velayati, Ali Akbar

    2015-01-01

    The soluble vascular endothelial growth factor receptor-1 (VEGFR1) or sFLT-1 has important role in antiangiogenesis. In this study, the increase expression and production of sFLT-1 fragment by newly designed ChPL-NPs nanoparticles (chitosan-protein lipid) using Chinese hamster ovary cell line (CHO) was evaluated. The assessment and purification of sFLT-1 were carried out by western blotting and fast protein liquid chromatography (FPLC). Thereafter, the angiostatic effect of gene transfer of sFLT-1 in Human umbilical vein endothelial cell line (HUVEC) was evaluated. Our results showed a significance rate of transfection with ChPL-NPs (80-85%) in comparison to standard lipofectamine(2000) (65-70%) (P < 0.05). The anti-angiogenic action of sFLT-1 was observed by in-vitro culture of recombinant protein (sFLT-1; 50 ng/ml) with HUVEC cell lines (5 × 10(6)). The ChPL-NPs nanoparticles can consider a potential carrier system for large scale production of sFLT-1, which ultimately may be use as therapeutic agent in targeting solid tumor tissues. PMID:25785168

  3. Effects of recombinant human endostatin on the expression of vascular endothelial growth factor in human gastric cancer cell line MGC-803

    PubMed Central

    WANG, YU-BIN; LIU, JUN-HONG; SONG, ZONG-MIN

    2013-01-01

    The present study aimed to explore the effects of recombinant human endostatin, endostar (ES), on the expression of vascular endothelial growth factor (VEGF) in the human gastric cancer cell line MGC-803. The expression of VEGF protein in MGC-803 cells was examined using immunohistochemistry. Subsequent to treatment with various concentrations of ES, the mRNA and VEGF protein expressions were determined in MGC-803 cells. A high level of VEGF protein expression was detected in MGC-803 cells. Subsequent to ES treatment, the mRNA and VEGF protein expressions were significantly decreased in MGC-803 cells (all P<0.05). In conclusion, ES is likely to inhibit the VEGF expression in MGC-803 cells. PMID:24648897

  4. Comparison of changes in endothelial adhesion molecule expression following UVB irradiation of skin and a human dermal microvascular cell line (HMEC-1).

    PubMed

    Rhodes, L E; Joyce, M; West, D C; Strickland, I; Friedmann, P S

    1996-06-01

    We have assessed the pattern of dermal endothelial adhesion molecule expression following broadband UVB irradiation in vivo and in vitro. Skin biopsies were taken from 4 human volunteers at baseline and at 4, 8 and 24 h post-irradiation with 2.5 minimal erythema doses of UVB. Sections were stained immunohistochemically for E-selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1). CD31 and neutrophil elastase. The effect of direct UVB irradiation on E-selectin, ICAM-1 and VCAM-1 was examined in a human dermal microvascular endothelial cell line, HMEC-1. Cultured HMEC-1 were irradiated with 2.5-40 mJ/cm2 of UVB, and assessed for adhesion molecule expression by immunofluorescence microscopy and fluorescence-activated cell sorter analysis. In vivo, E-selectin was minimally expressed on EC at baseline and was induced by 4 h following irradiation, P < 0.01. ICAM-1 was moderately expressed at baseline and appeared mildly induced at 24 h, although this did not reach statistical significance. VCAM-1 was weakly expressed in unirradiated skin while CD31 was moderately expressed, but neither was induced by UVB irradiation. A significant neutrophilic infiltrate appeared by 8 h and was maximal at 24 h, P < 0.05. Neutrophil infiltration correlated with E-selectin expression, r = 0.96. In HMEC-1, ICAM-1 was upregulated at 24 h post-irradiation, with an increase in mean channel fluorescence from 100% at baseline to 145 (SD12)% at 24 h, P < 0.05. No change was seen in expression of E-selectin, VCAM-1 or CD31. These studies support the involvement of endothelial adhesion molecules E-selectin and ICAM-1 in UVB-induced inflammation. Whereas ICAM-1 is upregulated by direct irradiation of endothelial cells, E-selectin stimulation appears to be an indirect effect. PMID:8956361

  5. Cell Lines

    PubMed Central

    Cherbas, Lucy; Gong, Lei

    2014-01-01

    We review the properties and uses of cell lines in Drosophila research, emphasizing the variety of lines, the large body of genomic and transcriptional data available for many of the lines, and the variety of ways the lines have been used to provide tools for and insights into the developmental, molecular, and cell biology of Drosophila and mammals. PMID:24434506

  6. Hexachlorobenzene promotes angiogenesis in vivo, in a breast cancer model and neovasculogenesis in vitro, in the human microvascular endothelial cell line HMEC-1.

    PubMed

    Pontillo, Carolina; Español, Alejandro; Chiappini, Florencia; Miret, Noelia; Cocca, Claudia; Alvarez, Laura; Kleiman de Pisarev, Diana; Sales, María Elena; Randi, Andrea Silvana

    2015-11-19

    Exposure to environmental pollutants may alter proangiogenic ability and promotes tumor growth. Hexachlorobenzene (HCB) is an organochlorine pesticide found in maternal milk and in lipid foods, and a weak ligand of the aryl hydrocarbon receptor (AhR). HCB induces migration and invasion in human breast cancer cells, as well as tumor growth and metastasis in vivo. In this study, we examined HCB action on angiogenesis in mammary carcinogenesis. HCB stimulates angiogenesis and increases vascular endothelial growth factor (VEGF) expression in a xenograft model with the human breast cancer cell line MDA-MB-231. Human microvascular endothelial cells HMEC-1 exposed to HCB (0.005, 0.05, 0.5 and 5μM) showed an increase in cyclooxygenase-2 (COX-2) and VEGF protein expression involving AhR. In addition, we found that HCB enhances VEGF-Receptor 2 (VEGFR2) expression, and activates its downstream pathways p38 and ERK1/2. HCB induces cell migration and neovasculogenesis in a dose-dependent manner. Cells pretreatment with AhR, COX-2 and VEGFR2 selective inhibitors, suppressed these effects. In conclusion, our results show that HCB promotes angiogenesis in vivo and in vitro. HCB-induced cell migration and tubulogenesis are mediated by AhR, COX-2 and VEGFR2 in HMEC-1. These findings may help to understand the association among HCB exposure, angiogenesis and mammary carcinogenesis. PMID:26358519

  7. Irradiation-Induced Regulation of Plasminogen Activator Inhibitor Type-1 and Vascular Endothelial Growth Factor in Six Human Squamous Cell Carcinoma Lines of the Head and Neck

    SciTech Connect

    Artman, Tuuli; Schilling, Daniela; Multhoff, Gabriele

    2010-02-01

    Purpose: It has been shown that plasminogen activator inhibitor type-1 (PAI-1) and vascular endothelial growth factor (VEGF) are involved in neo-angiogenesis. The aim of this study was to investigate the irradiation-induced regulation of PAI-1 and VEGF in squamous cell carcinomas of the head and neck (SCCHN) cell lines of varying radiation sensitivity. Methods and Materials: Six cell lines derived from SCCHN were investigated in vitro. The colorimetric AlamarBlue assay was used to detect metabolic activity of cell lines during irradiation as a surrogate marker for radiation sensitivity. PAI-1 and VEGF secretion levels were measured by enzyme-linked immunosorbent assay 24, 48, and 72 h after irradiation with 0, 2, 6, and 10 Gy. The direct radioprotective effect of exogenous PAI-1 was measured using the clonogenic assay. For regulation studies, transforming growth factor-beta1 (TGF-beta1), hypoxia-inducible factor-1alpha (HIF-1alpha), hypoxia-inducible factor-2alpha (HIF-2alpha), or both HIF-1alpha and HIF-2alpha were downregulated using siRNA. Results: Although baseline levels varied greatly, irradiation led to a comparable dose-dependent increase in PAI-1 and VEGF secretion in all six cell lines. Addition of exogenous stable PAI-1 to the low PAI-1-expressing cell lines, XF354 and FaDu, did not lead to a radioprotective effect. Downregulation of TGF-beta1 significantly decreased VEGF secretion in radiation-sensitive XF354 cells, and downregulation of HIF-1alpha and HIF-2alpha reduced PAI-1 and VEGF secretion in radiation-resistant SAS cells. Conclusions: Irradiation dose-dependently increased PAI-1 and VEGF secretion in all SCCHN cell lines tested regardless of their basal levels and radiation sensitivity. In addition, TGF-beta1 and HIF-1alpha could be partly responsible for VEGF and PAI-1 upregulation after irradiation.

  8. Up-regulation of drug-metabolizing enzyme genes in layered co-culture of a human liver cell line and endothelial cells.

    PubMed

    Ohno, Maki; Motojima, Kiyoto; Okano, Teruo; Taniguchi, Akiyoshi

    2008-11-01

    Primary human hepatocytes are used extensively to study drug-metabolizing enzymes such as the cytochrome P450 (CYP) enzymes. However, the activities of these enzymes decrease rapidly during culture. In the present study, using a thermo-responsive culture dish, layered co-culture was achieved by placing a bovine pulmonary artery endothelial cell (BPAEC) sheet onto the human hepatoma cell line HepG2. In the BPAEC/HepG2 layered co-culture system, real-time polymerase chain reaction analysis showed that the expression levels of various CYP enzymes were more than 10 times greater 21 days after layering than with a HepG2 monolayer. The expression levels of CYP1B1, CYP2C9, CYP2E1, and CYP3A4 were up-regulated in a time-dependent manner, gradually increasing from day 10 after layering, and continuing to increase until at least day 21. The gene expression levels of the various CYP enzymes were almost identical to that of human liver. These results suggest that our layered co-culture system enhances the function of HepG2 cells and that our BPAEC/HepG2 layered co-culture system can serve as a useful model for the in vitro evaluation of CYP regulation. PMID:18847370

  9. Ammonia inhibits the C-type natriuretic peptide-dependent cyclic GMP synthesis and calcium accumulation in a rat brain endothelial cell line.

    PubMed

    Konopacka, Agnieszka; Zielińska, Magdalena; Albrecht, Jan

    2008-05-01

    Recently we reported a decrease of C-type natriuretic peptide (CNP)-dependent, natriuretic peptide receptor 2 (NPR2)-mediated cyclic GMP (cGMP) synthesis in a non-neuronal compartment of cerebral cortical slices of hyperammonemic rats [Zielińska, M., Fresko, I., Konopacka, A., Felipo, V., Albrecht, J., 2007. Hyperammonemia inhibits the natriuretic peptide receptor 2 (NPR2)-mediated cyclic GMP synthesis in the astrocytic compartment of rat cerebral cortex slices. Neurotoxicology 28, 1260-1263]. Here we accounted for the possible involvement of cerebral capillary endothelial cells in this response by measuring the effect of ammonia on the CNP-mediated cGMP formation and intracellular calcium ([Ca2+]i) accumulation in a rat cerebral endothelial cell line (RBE-4). We first established that stimulation of cGMP synthesis in RBE-4 cells was coupled to protein kinase G (PKG)-mediated Ca2+ influx from the medium which was inhibited by an L-type channel blocker nimodipine. Ammonia treatment (1h, 5mM NH4Cl) evoked a substantial decrease of CNP-stimulated cGMP synthesis which was related to a decreased binding of CNP to NPR2 receptors, and depressed the CNP-dependent [Ca2+]i accumulation in these cells. Ammonia also abolished the CNP-dependent Ca2+ accumulation in the absence of Na+. In cells incubated with ammonia in the absence of Ca2+ a slight CNP-dependent increase of [Ca2+]i was observed, most likely representing Ca2+ release from intracellular stores. Depression of CNP-dependent cGMP-mediated [Ca2+]i accumulation may contribute to cerebral vascular endothelial dysfunction associated with hyperammonemia or hepatic encephalopathy. PMID:18222015

  10. Targeting vascular endothelial growth factor receptor-1 and -3 with cediranib (AZD2171): effects on migration and invasion of gastrointestinal cancer cell lines

    PubMed Central

    Morelli, M. Pia; Brown, Amy M.; Pitts, Todd M.; Tentler, John J.; Ciardiello, Fortunato; Ryan, Anderson; Jürgensmeier, Juliane M.; Eckhardt, S. Gail

    2010-01-01

    The effect of vascular endothelial growth factor (VEGF) ligands and cediranib on tumor cell proliferation, migration, and invasion was determined. It has recently been suggested that autocrine signaling through the VEGF receptor (VEGFR) pathway may play a role in tumor cell survival, invasion, and migration. The purpose of the present study was to determine the expression of VEGFRs and VEGFR ligands in a panel of gastrointestinal carcinoma cells. Additionally, we evaluated the effects of VEGF autocrine signaling on tumor cell proliferation, migration, and invasion utilizing cediranib (AZD2171), a pan-VEGFR inhibitor. Five colorectal, three pancreatic, and two hepatocellular carcinoma cell lines were screened for VEGFR and VEGF expression by several methods. Expression of VEGFR-1 and VEGFR-3 was cell line–dependent, whereas VEGFR-2 was not detected. Secretion of VEGF-A was detected in the supernatants of all cell lines whereas VEGF-C secretion was detected in the Panc-1,MiaPaca2, and Hep1 cells only. Tumor cells showed increased migratory activity, but not proliferation, when stimulated with VEGFs. The pan-VEGFR inhibitor cediranib (100 nmol/L) inhibited tumor cell migration and invasion, with no effects on proliferation. Cediranib decreased VEGFR-1 and VEGFR-3 phosphorylation as well as activation of downstream effectors. VEGFR-1 and VEGFR-3 expression was detected in all the gastrointestinal carcinoma cells evaluated. Although activation of the VEGF pathway did not affect cell proliferation, our data indicate that this pathway seems to play a role in tumor cell migration and invasion in these cell lines. Therefore, inhibition of VEGFR by cediranib may represent a clinically relevant treatment option for gastrointestinal tumors. PMID:19755510

  11. Plasticity of Blood- and Lymphatic Endothelial Cells and Marker Identification

    PubMed Central

    Keuschnigg, Johannes; Karinen, Sirkku; Auvinen, Kaisa; Irjala, Heikki; Mpindi, John-Patrick; Kallioniemi, Olli; Hautaniemi, Sampsa; Jalkanen, Sirpa; Salmi, Marko

    2013-01-01

    The distinction between lymphatic and blood vessels is biologically fundamental. Here we wanted to rigorously analyze the universal applicability of vascular markers and characteristics of the two widely used vascular model systems human microvascular endothelial cell line-1 (HMEC-1) and telomerase-immortalized microvascular endothelial cell line (TIME). Therefore we studied the protein expression and functional properties of the endothelial cell lines HMEC-1 and TIME by flow cytometry and in vitro flow assays. We then performed microarray analyses of the gene expression in these two cell lines and compared them to primary endothelial cells. Using bioinformatics we then defined 39 new, more universal, endothelial-type specific markers from 47 primary endothelial microarray datasets and validated them using immunohistochemistry with normal and pathological tissues. We surprisingly found that both HMEC-1 and TIME are hybrid blood- and lymphatic cells. In addition, we discovered great discrepancies in the previous identifications of blood- and lymphatic endothelium-specific genes. Hence we identified and validated new, universally applicable vascular markers. Summarizing, the hybrid blood-lymphatic endothelial phenotype of HMEC-1 and TIME is indicative of plasticity in the gene expression of immortalized endothelial cell lines. Moreover, we identified new, stable, vessel-type specific markers for blood- and lymphatic endothelium, useful for basic research and clinical diagnostics. PMID:24058540

  12. Effects of meloxicam on vascular endothelial growth factor and angiopoietin-2 expression in colon carcinoma cell line HT-29.

    PubMed

    Zhang, Ning; Tao, Kaixiong; Huang, Tao

    2007-08-01

    To investigate the effect of meloxicam, a selected NSAIDs, on cell growth, expression of VEGF and angiopointin-2 (Ang-2) protein in HT-29 cell line, cultured HT-29 cells were treated with meloxicam of various concentrations for various lengths of time. The proliferation of HT-29 was detected by cell counting kit-8 (CCK-8), the cell cycle was determined by flow cytometer and the levels of VEGF and Ang-2 protein in supernatants were examined by enzyme linked immunosorbent assay (ELISA). The mRNA expressions of VEGF and Ang-2 in cultured HT-29 were determined by real-time quantitative reverse-transcription polymerase chain reaction. Our results showed that treatment of meloxicam of different concentrations and for various lengths of time had a cytotoxicic effect on the cell proliferation of HT-29 cells in a concentration-dependant and time-dependant manner. Cell cycle analysis showed that the cells were mainly blocked in G0/G1 phase. The VEGF and Ang-2 protein levels in supernatants of the culture medium were decreased gradually in a concentration-dependent or time-dependent fashion. The mRNA expression of cox-2, VEGF and Ang-2 showed a gradual and concentration-dependent reduction. It is concluded that meloxicam can reduce the expression of VEGF and Ang-2 at the protein and mRNA level in colon carcinoma cell line. PMID:17828495

  13. Retinal Endothelial Cell Apoptosis Stimulates Recruitment of Endothelial Progenitor Cells

    PubMed Central

    Bhatwadekar, Ashay D.; Glenn, Josephine V.; Curtis, Tim M.; Grant, Maria B.; Stitt, Alan W.; Gardiner, Tom A.

    2013-01-01

    Purpose Bone marrow–derived endothelial progenitor cells (EPCs) contribute to vascular repair although it is uncertain how local endothelial cell apoptosis influences their reparative function. This study was conducted to determine how the presence of apoptotic bodies at sites of endothelial damage may influence participation of EPCs in retinal microvascular repair. Methods Microlesions of apoptotic cell death were created in monolayers of retinal microvascular endothelial cells (RMECs) by using the photodynamic drug verteporfin. The adhesion of early-EPCs to these lesions was studied before detachment of the apoptotic cells or after their removal from the wound site. Apoptotic bodies were fed to normal RMECs and mRNA levels for adhesion molecules were analyzed. Results Endothelial lesions where apoptotic bodies were left attached at the wound site showed a fivefold enhancement in EPC recruitment (P < 0.05) compared with lesions where the apoptotic cells had been removed. In intact RMEC monolayers exposed to apoptotic bodies, expression of ICAM, VCAM, and E-selectin was upregulated by 5- to 15-fold (P < 0.05– 0.001). EPCs showed a characteristic chemotactic response (P < 0.05) to conditioned medium obtained from apoptotic bodies, whereas analysis of the medium showed significantly increased levels of VEGF, IL-8, IL-6, and TNF-α when compared to control medium; SDF-1 remained unchanged. Conclusions The data indicate that apoptotic bodies derived from retinal capillary endothelium mediate release of proangiogenic cytokines and chemokines and induce adhesion molecule expression in a manner that facilitates EPC recruitment. PMID:19474402

  14. Endothelial progenitor cells: identity defined?

    PubMed Central

    Timmermans, Frank; Plum, Jean; Yöder, Mervin C; Ingram, David A; Vandekerckhove, Bart; Case, Jamie

    2009-01-01

    Abstract In the past decade, researchers have gained important insights on the role of bone marrow (BM)-derived cells in adult neovascularization. A subset of BM-derived cells, called endothelial progenitor cells (EPCs), has been of particular interest, as these cells were suggested to home to sites of neovascularization and neoendothelialization and differentiate into endothelial cells (ECs) in situ, a process referred to as postnatal vasculogenesis. Therefore, EPCs were proposed as a potential regenerative tool for treating human vascular disease and a possible target to restrict vessel growth in tumour pathology. However, conflicting results have been reported in the field, and the identification, characterization, and exact role of EPCs in vascular biology is still a subject of much discussion. The focus of this review is on the controversial issues in the field of EPCs which are related to the lack of a unique EPC marker, identification challenges related to the paucity of EPCs in the circulation, and the important phenotypical and functional overlap between EPCs, haematopoietic cells and mature ECs. We also discuss our recent findings on the origin of endothelial outgrowth cells (EOCs), showing that this in vitro defined EC population does not originate from circulating CD133+ cells or CD45+ haematopoietic cells. PMID:19067770

  15. Transcriptional targeting of tumor endothelial cells for gene therapy

    PubMed Central

    Dong, Zhihong; Nör, Jacques E.

    2009-01-01

    It is well known that angiogenesis plays a critical role in the pathobiology of tumors. Recent clinical trials have shown that inhibition of angiogenesis can be an effective therapeutic strategy for patients with cancer. However, one of the outstanding issues in anti-angiogenic treatment for cancer is the development of toxicities related to off-target effects of drugs. Transcriptional targeting of tumor endothelial cells involves the use of specific promoters for selective expression of therapeutic genes in the endothelial cells lining the blood vessels of tumors. Recently, several genes that are expressed specifically in tumor-associated endothelial cells have been identified and characterized. These discoveries have enhanced the prospectus of transcriptionaly targeting tumor endothelial cells for cancer gene therapy. In this manuscript, we review the promoters, vectors, and therapeutic genes that have been used for transcriptional targeting of tumor endothelial cells, and discuss the prospects of such approaches for cancer gene therapy. PMID:19393703

  16. Cloning and expression of the functional human anti-vascular endothelial growth factor (VEGF) using the pcDNA3.1 vector and the human chronic myelogenous leukemia cell line K562.

    PubMed

    Hajirezaei, Masoumeh; Darbouy, Mojtaba; Kazemi, Bahram

    2014-02-01

    In this study, the light chain (κ) and heavy chain (γ) sequences of the monoclonal antibody against vascular endothelial growth factor (VEGF) were sub-cloned into the eukaryotic pcDNA3.1 (+) (Hygro) and the pcDNA3.1 (+) (Neo) expression vectors using the traditional and homologous recombination methods. To express the antibody, the recombinant plasmids were transfected into the Chinese hamster ovary (CHO) and the K562 cell lines. The recombinant antibody was then purified using the protein A affinity chromatography. Furthermore, in order to demonstrate the inhibition of VEGF-induced mitogenesis of the recombinant antibody, the bovine aorta endothelial like cells were employed. The results showed specialization and conjunction of the recombinant antibody to the VEGF. It was also indicated that the antibody expression in the K562 cell lines was higher than the CHO cell lines. Furthermore, the in vitro VEGF inhabitation of the recombinant antibodies which were produced from the K562 cell line, and the CHO cell line, were similar. This proved that the K562 cell line is a good substitute for the CHO cell line in the production of the recombinant antibodies. PMID:24399318

  17. Endothelial Cells Derived From Nuclear Reprogramming

    PubMed Central

    Wong, Wing Tak; Huang, Ngan F.; Botham, Crystal M.; Sayed, Nazish; Cooke, John P.

    2012-01-01

    The endothelium plays a pivotal role in vascular homeostasis, regulating the tone of the vascular wall, and its interaction with circulating blood elements. Alterations in endothelial functions facilitate the infiltration of inflammatory cells and permit vascular smooth muscle proliferation and platelet aggregation. Therefore, endothelial dysfunction is an early event in disease processes including atherosclerosis, and because of its critical role in vascular health the endothelium is worthy of the intense focus it has received. However, there are limitations to studying human endothelial function in vivo, or human vascular segments ex vivo. Thus, methods for endothelial cell culture have been developed and refined. More recently, methods to derive endothelial cells from pluripotent cells have extended the scientific range of human endothelial cell studies. Pluripotent stem cells may be generated, expanded and then differentiated into endothelial cells for in vitro studies. Constructs for molecular imaging can also be employed to facilitate tracking these cells in vivo. Furthermore, one can generate patient-specific endothelial cells to study the effects of genetic or epigenetic alterations on endothelial behavior. Finally, there is the opportunity to apply these cells for vascular therapy. This review focuses on the generation of endothelial cells from stem cells; their characterization by genetic, histological and functional studies; and their translational applications. PMID:23104878

  18. Development of Endothelial-Specific Single Inducible Lentiviral Vectors for Genetic Engineering of Endothelial Progenitor Cells

    PubMed Central

    Yang, Guanghua; Kramer, M. Gabriela; Fernandez-Ruiz, Veronica; Kawa, Milosz P.; Huang, Xin; Liu, Zhongmin; Prieto, Jesus; Qian, Cheng

    2015-01-01

    Endothelial progenitor cells (EPC) are able to migrate to tumor vasculature. These cells, if genetically modified, can be used as vehicles to deliver toxic material to, or express anticancer proteins in tumor. To test this hypothesis, we developed several single, endothelial-specific, and doxycycline-inducible self-inactivating (SIN) lentiviral vectors. Two distinct expression cassettes were inserted into a SIN-vector: one controlled by an endothelial lineage-specific, murine vascular endothelial cadherin (mVEcad) promoter for the expression of a transactivator, rtTA2S-M2; and the other driven by an inducible promoter, TREalb, for a firefly luciferase reporter gene. We compared the expression levels of luciferase in different vector constructs, containing either the same or opposite orientation with respect to the vector sequence. The results showed that the vector with these two expression cassettes placed in opposite directions was optimal, characterized by a robust induction of the transgene expression (17.7- to 73-fold) in the presence of doxycycline in several endothelial cell lines, but without leakiness when uninduced. In conclusion, an endothelial lineage-specific single inducible SIN lentiviral vector has been developed. Such a lentiviral vector can be used to endow endothelial progenitor cells with anti-tumor properties. PMID:26612671

  19. Development of Endothelial-Specific Single Inducible Lentiviral Vectors for Genetic Engineering of Endothelial Progenitor Cells.

    PubMed

    Yang, Guanghua; Kramer, M Gabriela; Fernandez-Ruiz, Veronica; Kawa, Milosz P; Huang, Xin; Liu, Zhongmin; Prieto, Jesus; Qian, Cheng

    2015-01-01

    Endothelial progenitor cells (EPC) are able to migrate to tumor vasculature. These cells, if genetically modified, can be used as vehicles to deliver toxic material to, or express anticancer proteins in tumor. To test this hypothesis, we developed several single, endothelial-specific, and doxycycline-inducible self-inactivating (SIN) lentiviral vectors. Two distinct expression cassettes were inserted into a SIN-vector: one controlled by an endothelial lineage-specific, murine vascular endothelial cadherin (mVEcad) promoter for the expression of a transactivator, rtTA2S-M2; and the other driven by an inducible promoter, TREalb, for a firefly luciferase reporter gene. We compared the expression levels of luciferase in different vector constructs, containing either the same or opposite orientation with respect to the vector sequence. The results showed that the vector with these two expression cassettes placed in opposite directions was optimal, characterized by a robust induction of the transgene expression (17.7- to 73-fold) in the presence of doxycycline in several endothelial cell lines, but without leakiness when uninduced. In conclusion, an endothelial lineage-specific single inducible SIN lentiviral vector has been developed. Such a lentiviral vector can be used to endow endothelial progenitor cells with anti-tumor properties. PMID:26612671

  20. Endothelial cells in dengue hemorrhagic fever.

    PubMed

    Srikiatkhachorn, Anon; Kelley, James F

    2014-09-01

    Therapies to prevent or reverse endothelial dysfunction and vascular leak found in dengue hemorrhagic fever (DHF) have not been identified. In this review we summarize dengue viruses and the spectrum of human disease and highlight evidence of endothelial cell dysfunction in DHF based on studies in patients and mouse and tissue culture models. Evidence suggests that both virus antigen and host immune response, can cause endothelial cell dysfunction and weaken endothelial barrier integrity. We suggest possible therapeutic interventions and highlight how therapies targeting altered endothelial function might be evaluated in animal models and in patients with DHF. PMID:25025934

  1. Endothelial cell micropatterning: Methods, effects, and applications

    PubMed Central

    Anderson, Deirdre E.J.; Hinds, Monica T.

    2012-01-01

    The effects of flow on endothelial cells have been widely examined for the ability of fluid shear stress to alter cell morphology and function; however, the effects of endothelial cell morphology without flow have only recently been observed. An increase in lithographic techniques in cell culture spurred a corresponding increase in research aiming to confine cell morphology. These studies lead to a better understanding of how morphology and cytoskeletal configuration affect the structure and function of the cells. This review examines endothelial cell micropatterning research by exploring both the many alternative methods used to alter endothelial cell morphology and the resulting changes in cellular shape and phenotype. Micropatterning induced changes in endothelial cell proliferation, apoptosis, cytoskeletal organization, mechanical properties, and cell functionality. Finally, the ways these cellular manipulation techniques have been applied to biomedical engineering research, including angiogenesis, cell migration, and tissue engineering, is discussed. PMID:21761242

  2. Progenitor endothelial cell involvement in Alzheimer's disease

    SciTech Connect

    Budinger, Thomas F.

    2003-05-01

    There is compelling evidence that endothelial cells of the brain and periphery are dysfunctional in Alzheimer's Disease. There is evidence for a fundamental defect in, or abnormal aging of, endothelial progenitor cells in atherosclerosis. The possibility that endothelial cell defects are a primary cause for Alzheimer's Disease or other dementias can be researched by molecular and cell biology studies as well as cell trafficking studies using recently demonstrated molecular imaging methods. The evidence for abnormal endothelial function and the methods to explore this hypothesis are presented.

  3. Morphological study of endothelial cells during freezing

    NASA Astrophysics Data System (ADS)

    Zhang, A.; Xu, L. X.; Sandison, G. A.; Cheng, S.

    2006-12-01

    Microvascular injury is recognized as a major tissue damage mechanism of ablative cryosurgery. Endothelial cells lining the vessel wall are thought to be the initial target of freezing. However, details of this injury mechanism are not yet completely understood. In this study, ECMatrix™ 625 was used to mimic the tumour environment and to allow the endothelial cells cultured in vitro to form the tube-like structure of the vasculature. The influence of water dehydration on the integrity of this structure was investigated. It was found that the initial cell shape change was mainly controlled by water dehydration, dependent on the cooling rate, resulting in the shrinkage of cells in the direction normal to the free surface. As the cooling was prolonged and temperature was lowered, further cell shape change could be induced by the chilling effects on intracellular proteins, and focal adhesions to the basement membrane. Quantitative analysis showed that the freezing induced dehydration greatly enhanced the cell surface stresses, especially in the axial direction. This could be one of the major causes of the final breaking of the cell junction and cell detachment.

  4. Endothelial cells enhance migration of meniscus cells

    PubMed Central

    Yuan, Xiaoning; Eng, George M.; Arkonac, Derya E.; Chao, Pen-hsiu Grace; Vunjak-Novakovic, Gordana

    2014-01-01

    Objective To study the interactions between vascular endothelial cells and meniscal fibrochondrocytes from the inner avascular and outer vascular regions of the meniscus, and identify angiogenic factors that enhance cell migration and integrative repair. Methods Bovine meniscal fibrochondrocytes (bMFCs) from the inner and outer regions of meniscus were cultured for seven days with and without human umbilical vein endothelial cells (HUVECs) in a micropatterned three-dimensional hydrogel system for cell migration. Angiogenic factors secreted by HUVECs were probed for their role in paracrine mechanisms governing bMFC migration, and applied to a full-thickness defect model of meniscal repair in explants from the inner and outer regions over four weeks. Results Endothelial cells enhanced migration of inner and outer bMFCs in the micropatterned system via endothelin-1 (ET-1) signaling. Supplementation of ET-1 significantly enhanced integration strength of full-thickness defects in inner and outer explants, and cell migration at the macro-scale, compared to controls without ET-1 treatment. Conclusion We report for the first time that bMFCs from both the avascular and vascular regions respond to the presence of endothelial cells with increased migration. Paracrine signaling by endothelial cells regulates the bMFCs differentially by region, but we identify ET-1 as an angiogenic factor that stimulates migration of inner and outer cells at the micro-scale, and integrative repair of inner and outer explants at the macro-scale. These findings reveal the regional interactions between vasculature and MFCs, and suggest ET-1 as a potential new treatment modality for avascular meniscal injuries, in order to prevent the development of osteoarthritis. PMID:25307081

  5. Replication of human endothelial cells in culture.

    PubMed

    Lewis, L J; Hoak, J C; Maca, R D; Fry, G L

    1973-08-01

    Investigative studies dealing with the properties and functions of endothelial cells have been hampered because there has been little or no success in the isolation, growth, and passage of individual cells in large numbers. We have developed a system whereby pure cultures of endothelial cells derived from umbilical veins can be subcultured for at least five serial passages. Many facets of endothelial function and interaction can be evaluated with the use of this new adaptive system of isolation and culture. PMID:4718112

  6. [Transplantation of corneal endothelial cells].

    PubMed

    Amano, Shiro

    2002-12-01

    Though conventional corneal transplantation has achieved great success, it still has several drawbacks including limited availability of donor corneas, recurrent allograft rejection, and subsequent graft failure in certain cases. Reconstructing clinically usable corneas by applying the technology of regenerative medicine can offer a solution to these problems, as well as making corneal transplantation a non-emergency surgery and enabling the usage of banked corneal cells. In the present study, we focused on corneal endothelium that is critical for corneal transparency and investigated the reconstruction of cornea utilizing cultured human corneal endothelial cells (HCECs). We succeeded in steadily culturing HCECs by using culture dishes pre-coated with extracellular matrix produced by calf corneal endothelial cells and culture media that contained basic fibroblast growth factor and fetal bovine serum. We performed the following analysis utilizing these cultured HCECs. The older the donor was, the more frequently large senescent cells appeared in the passaged HCECs. The telomeres of HCECs were measured as terminal restriction fragments (TRF) by Southern blotting. HCECs, in vivo from donors in their seventies had a long TRFs of over 12 kilobases. Passaging shortened the TRFs but there was no difference in TRFs among donors of various ages. These results indicated that shortening of telomere length is not related to senescence of HCECs. We investigated the role of advanced glycation end products (AGEs) in the senescence of in vivo HCECs. The results indicated that AGE-protein in the aqueous humor is endocytosed into HCECs via AGE receptors expressed on the surface of HCECs and damages HCECs by producing reactive oxygen species and inducing apoptosis, suggesting that AGEs, at least partly, cause the senescence of HECEs. HCECs were cultured using adult human serum instead of bovine serum to get rid of bovine material that can be infected with prions. Primary and passage

  7. Human liver endothelial cells, but not macrovascular or microvascular endothelial cells, engraft in the mouse liver.

    PubMed

    Filali, Ebtisam El; Hiralall, Johan K; van Veen, Henk A; Stolz, Donna B; Seppen, Jurgen

    2013-01-01

    Liver cell transplantation has had limited clinical success so far, partly due to poor engraftment of hepatocytes. Instead of hepatocytes. other cell types, such as endothelial cells, could be used in ex vivo liver gene therapy. The goal of the present study was to compare the grafting and repopulation capacity of human endothelial cells derived from various tissues. Human endothelial cells were isolated from adult and fetal livers using anti-human CD31 antibody-conjugated magnetic beads. Human macrovascular endothelial cells were obtained from umbilical vein. Human microvascular endothelial cells were isolated from adipose tissue. Cells were characterized using flow cytometry. Liver engraftment and repopulation of endothelial cells was studied after intrasplenic transplantation in monocrotaline-treated immunodeficient mice. Following transplantation, human liver endothelial cells engrafted throughout the mouse liver. With immunoscanning electron microscopy, fenestrae in engrafted human liver endothelial cells were identified, a characteristic feature of liver sinusoidal endothelial cells. In contrast, CD31-negative liver cells, human macrovascular and microvascular endothelial cells were not capable of repopulating mouse liver. Characterization of human liver, macrovascular, and microvascular endothelial cells demonstrated expression of CD31, CD34, and CD146 but not CD45. Our study shows that only human liver endothelial cells, but not macro- and microvascular endothelial cells, have the unique capacity to engraft and repopulate the mouse liver. These results indicate that mature endothelial cells cannot transdifferentiate in vivo and thus do not exhibit phenotypic plasticity. Our results have set a basis for further research to the potential of human liver endothelial cells in liver-directed cell and gene therapy. PMID:23044355

  8. Effects of ultrasound upon endothelial cell ultrastructure

    NASA Astrophysics Data System (ADS)

    Rodemer, Claus; Jenne, Jürgen; Fatar, Marc; Hennerici, Michael G.; Meairs, Stephen

    2012-11-01

    A number of new brain applications for therapeutic ultrasound are emerging including drug delivery through BBB opening, enhancement of angiogenesis, sonothrombolysis and neuromodulation. Safety remains important as alterations in the cytoskeleton and tight junctions of endothelial cells have been described. In this study we characterize the in vitro effects of ultrasound on cell morphology using a new human brain cell line (hCMEC/D3). Changes in ultrastructure were analyzed with antibodies against tubulin, actin and catenin. Transport was analyzed by measuring transferrin uptake. No significant changes were seen after continuous wave ultrasound treatment of hCMEC/D3 cells grown in Opticell{trade mark, serif} chambers. We could not observe disassembled actin stress fibers or variations in the microtubule network. However, severe damage occurred in cells cultured in petri dishes.

  9. PEROXYNITRITE IS A POTENT INHIBITOR OF NF-κ B ACTIVATION TRIGGERED BY INFLAMMATORY STIMULI IN CARDIAC AND ENDOTHELIAL CELL LINES

    PubMed Central

    Levrand, Sandra; Pesse, Benoît; Feihl, François; Waeber, Bernard; Pacher, Pal; Rolli, Joëlle; Schaller, Marie-Denise; Liaudet, Lucas

    2008-01-01

    Peroxynitrite is a potent oxidant and nitrating species proposed as a direct effector of myocardial damage in numerous cardiac pathologies. Whether peroxynitrite also acts indirectly, by modulating cell signal transduction in the myocardium, has not been investigated. We therefore examined a possible role of peroxynitrite on the activation of NF-κ B, a crucial pro-inflammatory transcription factor, in cultured H9C2 cardiomyocytes. H9C2 cells were stimulated with TNF α or LPS following a brief (20 min) exposure to peroxynitrite. NF-κB activation (phosphorylation and degradation of its inhibitor I κ B α , nuclear translocation of NF-κ B p65 and NF-κ B DNA binding) triggered by LPS or TNF α was abrogated by peroxynitrite. Peroxynitrite also inhibited NF-κ B in 2 human endothelial cell lines activated with TNF α or IL-1 β . These effects were related to oxidative, but not nitrative chemistry, being still observed while nitration was suppressed by epicatechin. The mechanism of NF-κ B inhibition by peroxynitrite was a complete blockade of phosphorylation and activation of the upstream kinase IKK β , required for canonical, pro-inflammatory NF-κ B activation. At the same time, peroxynitrite activated phosphorylation of NIK and IKK α , considered as part of an alternative, non canonical NF-κ B activation pathway. Suppression of IKK β-dependent NF-κ B activation translated into a marked inhibition of the transcription of NF-κ B dependent genes by peroxynitrite. Thus, peroxynitrite has a dual effect on NF-κ B, inhibiting canonical IKK β-dependent NF-κ B activation while activating NIK and IKK α phosphorylation, which suggests its involvement in an alternative pathway of NF-κ B activation. These findings offer new perspectives in the understanding of the relationships between redox stress and inflammation. PMID:16079150

  10. Activated Brain Endothelial Cells Cross-Present Malaria Antigen

    PubMed Central

    Howland, Shanshan W.; Poh, Chek Meng; Rénia, Laurent

    2015-01-01

    In the murine model of cerebral malaria caused by P. berghei ANKA (PbA), parasite-specific CD8+ T cells directly induce pathology and have long been hypothesized to kill brain endothelial cells that have internalized PbA antigen. We previously reported that brain microvessel fragments from infected mice cross-present PbA epitopes, using reporter cells transduced with epitope-specific T cell receptors. Here, we confirm that endothelial cells are the population responsible for cross-presentation in vivo, not pericytes or microglia. PbA antigen cross-presentation by primary brain endothelial cells in vitro confers susceptibility to killing by CD8+ T cells from infected mice. IFNγ stimulation is required for brain endothelial cross-presentation in vivo and in vitro, which occurs by a proteasome- and TAP-dependent mechanism. Parasite strains that do not induce cerebral malaria were phagocytosed and cross-presented less efficiently than PbA in vitro. The main source of antigen appears to be free merozoites, which were avidly phagocytosed. A human brain endothelial cell line also phagocytosed P. falciparum merozoites. Besides being the first demonstration of cross-presentation by brain endothelial cells, our results suggest that interfering with merozoite phagocytosis or antigen processing may be effective strategies for cerebral malaria intervention. PMID:26046849

  11. Macrophage migration inhibitory factor up-regulates alpha(v)beta(3) integrin and vascular endothelial growth factor expression in endometrial adenocarcinoma cell line Ishikawa.

    PubMed

    Bondza, Patrick Kibangou; Metz, Christine N; Akoum, Ali

    2008-04-01

    Human endometrium undergoes a series of dynamic physiological changes during the menstrual cycle of reproductive age women. Many factors, including hormones, cytokines, growth factors, matrix metalloproteinases and integrins, are essential for the success of embryonic implantation into endometrial tissue. Herein, we used a well-differentiated endometrial adenocarcinoma cell line, Ishikawa, to investigate in vitro the role played by macrophage migration inhibitory factor (MIF) in the regulation of endometrial receptivity markers. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that MIF induced a slight increase in alpha(v) (alphav) mRNA integrin subunit expression during the first 12h, but reached a significant difference after 24h MIF treatment compared to control, whereas beta(3) (beta3) integrin subunit displayed significant increase in mRNA 2h following treatment. Immunocytofluorescence showed strong alphav and beta3 immunostaining at 25 ng/ml MIF, and Western blotting clearly indicated increased alphav and beta3 protein expression. MIF treatment significantly stimulated vascular endothelial growth factor (VEGF) mRNA expression in a dose- and time-dependent manner after 24 h treatment. Moreover, immunocytofluorescence revealed positive VEGF immunostaining compared to control, and analysis by ELISA of VEGF release in culture supernatants demonstrated that MIF (25 ng/ml) significantly induced VEGF secretion at 12 and 24 h. In conclusion, this study provides evidence that MIF directly up-regulates alphavbeta3 integrin and VEGF expression in human endometrial Ishikawa cells and may advance our understanding of factors involved in the establishment of endometrial receptivity and successful implantation. PMID:17854909

  12. Signaling hierarchy regulating human endothelial cell development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our present knowledge of the regulation of mammalian endothelial cell differentiation has been largely derived from studies of mouse embryonic development. However, unique mechanisms and hierarchy of signals that govern human endothelial cell development are unknown and, thus, explored in these stud...

  13. Endothelial Cell Dysfunction and the Pathobiology of Atherosclerosis.

    PubMed

    Gimbrone, Michael A; García-Cardeña, Guillermo

    2016-02-19

    Dysfunction of the endothelial lining of lesion-prone areas of the arterial vasculature is an important contributor to the pathobiology of atherosclerotic cardiovascular disease. Endothelial cell dysfunction, in its broadest sense, encompasses a constellation of various nonadaptive alterations in functional phenotype, which have important implications for the regulation of hemostasis and thrombosis, local vascular tone and redox balance, and the orchestration of acute and chronic inflammatory reactions within the arterial wall. In this review, we trace the evolution of the concept of endothelial cell dysfunction, focusing on recent insights into the cellular and molecular mechanisms that underlie its pivotal roles in atherosclerotic lesion initiation and progression; explore its relationship to classic, as well as more recently defined, clinical risk factors for atherosclerotic cardiovascular disease; consider current approaches to the clinical assessment of endothelial cell dysfunction; and outline some promising new directions for its early detection and treatment. PMID:26892962

  14. Production of soluble Neprilysin by endothelial cells

    SciTech Connect

    Kuruppu, Sanjaya; Rajapakse, Niwanthi W.; Minond, Dmitriy; Smith, A. Ian

    2014-04-04

    Highlights: • A soluble full-length form of Neprilysin exists in media of endothelial cells. • Exosomal release is the key mechanism for the production of soluble Neprilysin. • Inhibition of ADAM-17 by specific inhibitors reduce Neprilysin release. • Exosome mediated release of Neprilysin is dependent on ADAM-17 activity. - Abstract: A non-membrane bound form of Neprilysin (NEP) with catalytic activity has the potential to cleave substrates throughout the circulation, thus leading to systemic effects of NEP. We used the endothelial cell line Ea.hy926 to identify the possible role of exosomes and A Disintegrin and Metalloprotease 17 (ADAM-17) in the production of non-membrane bound NEP. Using a bradykinin based quenched fluorescent substrate (40 μM) assay, we determined the activity of recombinant human NEP (rhNEP; 12 ng), and NEP in the media of endothelial cells (10% v/v; after 24 h incubation with cells) to be 9.35 ± 0.70 and 6.54 ± 0.41 μmols of substrate cleaved over 3 h, respectively. The presence of NEP in the media was also confirmed by Western blotting. At present there are no commercially available inhibitors specific for ADAM-17. We therefore synthesised two inhibitors TPI2155-14 and TPI2155-17, specific for ADAM-17 with IC{sub 50} values of 5.36 and 4.32 μM, respectively. Treatment of cells with TPI2155-14 (15 μM) and TPI2155-17 (4.3 μM) resulted in a significant decrease in NEP activity in media (62.37 ± 1.43 and 38.30 ± 4.70, respectively as a % of control; P < 0.0001), implicating a possible role for ADAM-17 in NEP release. However, centrifuging media (100,000g for 1 h at 4 °C) removed all NEP activity from the supernatant indicating the likely role of exosomes in the release of NEP. Our data therefore indicated for the first time that NEP is released from endothelial cells via exosomes, and that this process is dependent on ADAM-17.

  15. Differential Adhesion of Tumor Cells to Capillary Endothelial Cells in vitro

    NASA Astrophysics Data System (ADS)

    Alby, Laverna; Auerbach, Robert

    1984-09-01

    Adhesion studies were carried out to determine the relative ability of glioma cells and ovary-derived teratoma cells to adhere to endothelial cells obtained from mouse brain capillaries (designated MBE cell line) or mouse ovaries (designated MOE cell line). The teratoma cells showed preferential adhesion to MOE cells, whereas the glioma cells showed preferential adhesion to the MBE cell line. In contrast, the glioma and teratoma cells adhered equally to L929 and 3T3 fibroblasts. A testicular teratoma with ovary-seeking properties in vivo also adhered preferentially to MOE cells, while the preference for MBE cells was shared by glioma cells with an endothelioma and a bladder tumor line. The endothelioma, interestingly, showed a marked preferential adhesion to 3T3 cells, thus distinguishing it from the glioma. The experiments demonstrate that capillary endothelial cells derived from different sources are not alike and that differences expressed at the cell surface of these cells can be distinguished by tumor cells.

  16. Increased endothelial cell permeability in endoglin-deficient cells.

    PubMed

    Jerkic, Mirjana; Letarte, Michelle

    2015-09-01

    Endoglin (ENG) is a TGF-β superfamily coreceptor essential for vascular endothelium integrity. ENG mutations lead to a vascular dysplasia associated with frequent hemorrhages in multiple organs, whereas ENG null mouse embryos die at midgestation with impaired heart development and leaky vasculature. ENG interacts with several proteins involved in cell adhesion, and we postulated that it regulates vascular permeability. The current study assessed the permeability of ENG homozygous null (Eng(-/-)), heterozygous (Eng(+/-)), and normal (Eng(+/+)) mouse embryonic endothelial cell (EC) lines. Permeability, measured by passage of fluorescent dextran through EC monolayers, was increased 2.9- and 1.7-fold for Eng(-/-) and Eng(+/-) ECs, respectively, compared to control ECs and was not increased by TGF-β1 or VEGF. Prolonged starvation increased Eng(-/-) EC permeability by 3.7-fold with no effect on control ECs; neutrophils transmigrated faster through Eng(-/-) than Eng(+/+) monolayers. Using a pull-down assay, we demonstrate that Ras homolog gene family (Rho) A is constitutively active in Eng(-/-) and Eng(+/-) ECs. We show that the endothelial barrier destabilizing factor thrombospondin-1 and its receptor-like protein tyrosine phosphatase are increased, whereas stabilizing factors VEGF receptor 2, vascular endothelial-cadherin, p21-activated kinase, and Ras-related C3 botulinum toxin substrate 2 are decreased in Eng(-/-) cells. Our findings indicate that ENG deficiency leads to EC hyperpermeability through constitutive activation of RhoA and destabilization of endothelial barrier function. PMID:25972355

  17. Fibrinogen induces endothelial cell permeability

    PubMed Central

    Tyagi, Neetu; Roberts, Andrew M.; Dean, William L.; Tyagi, Suresh C.

    2010-01-01

    Many cardiovascular and cerebrovascular disorders are accompanied by an increased blood content of fibrinogen (Fg), a high molecular weight plasma adhesion protein. Fg is a biomarker of inflammation and its degradation products have been associated with microvascular leakage. We tested the hypothesis that at pathologically high levels, Fg increases endothelial cell (EC) permeability through extracellular signal regulated kinase (ERK) signaling and by inducing F-actin formation. In cultured ECs, Fg binding to intercellular adhesion molecule-1 and to α5β1 integrin, caused phosphorylation of ERK. Subsequently, F-actin formation increased and coincided with formation of gaps between ECs, which corresponded with increased permeability of ECs to albumin. Our data suggest that formation of F-actin and gaps may be the mechanism for increased albumin leakage through the EC monolayer. The present study indicates that elevated un-degraded Fg may be a factor causing microvascular permeability that typically accompanies cardiovascular and cerebrovascular disorders. PMID:17849175

  18. Neuropilin2 expressed in gastric cancer endothelial cells increases the proliferation and migration of endothelial cells in response to VEGF

    SciTech Connect

    Kim, Woo Ho; Lee, Sun Hee; Jung, Myung Hwan; Seo, Ji Heun; Kim, Jin; Kim, Min A; Lee, You Mie

    2009-08-01

    The structure and characteristics of the tumor vasculature are known to be different from those of normal vessels. Neuropilin2 (Nrp2), which is expressed in non-endothelial cell types, such as neuronal or cancer cells, functions as a receptor for both semaphorin and vascular endothelial growth factor (VEGF). After isolating tumor and normal endothelial cells from advanced gastric cancer tissue and normal gastric mucosa tissues, respectively, we identified genes that were differentially expressed in gastric tumor endothelial (TEC) and normal endothelial cells (NEC) using DNA oligomer chips. Using reverse transcriptase-PCR, we confirmed the chip results by showing that Nrp2 gene expression is significantly up-regulated in TEC. Genes that were found to be up-regulated in TEC were also observed to be up-regulated in human umbilical vein endothelial cells (HUVECs) that were co-cultured with gastric cancer cells. In addition, HUVECs co-cultured with gastric cancer cells showed an increased reactivity to VEGF-induced proliferation and migration. Moreover, overexpression of Nrp2 in HUVECs significantly enhanced the proliferation and migration induced by VEGF. Observation of an immunohistochemical analysis of various human tumor tissue arrays revealed that Nrp2 is highly expressed in the tumor vessel lining and to a lesser extent in normal tissue microvessels. From these results, we suggest that Nrp2 may function to increase the response to VEGF, which is more significant in TEC than in NEC given the differential expression, leading to gastric TEC with aggressive angiogenesis phenotypes.

  19. Neuropilin2 expressed in gastric cancer endothelial cells increases the proliferation and migration of endothelial cells in response to VEGF.

    PubMed

    Kim, Woo Ho; Lee, Sun Hee; Jung, Myung Hwan; Seo, Ji Heun; Kim, Jin; Kim, Min A; Lee, You Mie

    2009-08-01

    The structure and characteristics of the tumor vasculature are known to be different from those of normal vessels. Neuropilin2 (Nrp2), which is expressed in non-endothelial cell types, such as neuronal or cancer cells, functions as a receptor for both semaphorin and vascular endothelial growth factor (VEGF). After isolating tumor and normal endothelial cells from advanced gastric cancer tissue and normal gastric mucosa tissues, respectively, we identified genes that were differentially expressed in gastric tumor endothelial (TEC) and normal endothelial cells (NEC) using DNA oligomer chips. Using reverse transcriptase-PCR, we confirmed the chip results by showing that Nrp2 gene expression is significantly up-regulated in TEC. Genes that were found to be up-regulated in TEC were also observed to be up-regulated in human umbilical vein endothelial cells (HUVECs) that were co-cultured with gastric cancer cells. In addition, HUVECs co-cultured with gastric cancer cells showed an increased reactivity to VEGF-induced proliferation and migration. Moreover, overexpression of Nrp2 in HUVECs significantly enhanced the proliferation and migration induced by VEGF. Observation of an immunohistochemical analysis of various human tumor tissue arrays revealed that Nrp2 is highly expressed in the tumor vessel lining and to a lesser extent in normal tissue microvessels. From these results, we suggest that Nrp2 may function to increase the response to VEGF, which is more significant in TEC than in NEC given the differential expression, leading to gastric TEC with aggressive angiogenesis phenotypes. PMID:19409892

  20. Immunological functions of liver sinusoidal endothelial cells.

    PubMed

    Knolle, Percy A; Wohlleber, Dirk

    2016-05-01

    Liver sinusoidal endothelial cells (LSECs) line the liver sinusoids and separate passenger leukocytes in the sinusoidal lumen from hepatocytes. LSECs further act as a platform for adhesion of various liver-resident immune cell populations such as Kupffer cells, innate lymphoid cells or liver dendritic cells. In addition to having an extraordinary scavenger function, LSECs possess potent immune functions, serving as sentinel cells to detect microbial infection through pattern recognition receptor activation and as antigen (cross)-presenting cells. LSECs cross-prime naive CD8 T cells, causing their rapid differentiation into memory T cells that relocate to secondary lymphoid tissues and provide protection when they re-encounter the antigen during microbial infection. Cross-presentation of viral antigens by LSECs derived from infected hepatocytes triggers local activation of effector CD8 T cells and thereby assures hepatic immune surveillance. The immune function of LSECs complements conventional immune-activating mechanisms to accommodate optimal immune surveillance against infectious microorganisms while preserving the integrity of the liver as a metabolic organ. PMID:27041636

  1. Apicobasal polarity of brain endothelial cells.

    PubMed

    Worzfeld, Thomas; Schwaninger, Markus

    2016-02-01

    Normal brain homeostasis depends on the integrity of the blood-brain barrier that controls the access of nutrients, humoral factors, and immune cells to the CNS. The blood-brain barrier is composed mainly of brain endothelial cells. Forming the interface between two compartments, they are highly polarized. Apical/luminal and basolateral/abluminal membranes differ in their lipid and (glyco-)protein composition, allowing brain endothelial cells to secrete or transport soluble factors in a polarized manner and to maintain blood flow. Here, we summarize the basic concepts of apicobasal cell polarity in brain endothelial cells. To address potential molecular mechanisms underlying apicobasal polarity in brain endothelial cells, we draw on investigations in epithelial cells and discuss how polarity may go awry in neurological diseases. PMID:26661193

  2. Blood cells and endothelial barrier function.

    PubMed

    Rodrigues, Stephen F; Granger, D Neil

    2015-01-01

    The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of soluble mediators from resident cells (e.g., mast cells, macrophages) and/or recruited blood cells. The interaction of the mediators with receptors expressed on the surface of endothelial cells diminishes barrier function either by altering the expression of adhesive proteins in the inter-endothelial junctions, by altering the organization of the cytoskeleton, or both. Reactive oxygen species (ROS), proteolytic enzymes (e.g., matrix metalloproteinase, elastase), oncostatin M, and VEGF are part of a long list of mediators that have been implicated in endothelial barrier failure. In this review, we address the role of blood borne cells, including, neutrophils, lymphocytes, monocytes, and platelets, in the regulation of endothelial barrier function in health and disease. Attention is also devoted to new targets for therapeutic intervention in disease states with morbidity and mortality related to endothelial barrier dysfunction. PMID:25838983

  3. Blood cells and endothelial barrier function

    PubMed Central

    Rodrigues, Stephen F; Granger, D Neil

    2015-01-01

    Abstract The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of soluble mediators from resident cells (e.g., mast cells, macrophages) and/or recruited blood cells. The interaction of the mediators with receptors expressed on the surface of endothelial cells diminishes barrier function either by altering the expression of adhesive proteins in the inter-endothelial junctions, by altering the organization of the cytoskeleton, or both. Reactive oxygen species (ROS), proteolytic enzymes (e.g., matrix metalloproteinase, elastase), oncostatin M, and VEGF are part of a long list of mediators that have been implicated in endothelial barrier failure. In this review, we address the role of blood borne cells, including, neutrophils, lymphocytes, monocytes, and platelets, in the regulation of endothelial barrier function in health and disease. Attention is also devoted to new targets for therapeutic intervention in disease states with morbidity and mortality related to endothelial barrier dysfunction. PMID:25838983

  4. Transcript Analysis Reveals a Specific HOX Signature Associated with Positional Identity of Human Endothelial Cells

    PubMed Central

    Toshner, Mark; Dunmore, Benjamin J.; McKinney, Eoin F.; Southwood, Mark; Caruso, Paola; Upton, Paul D.; Waters, John P.; Ormiston, Mark L.; Skepper, Jeremy N.; Nash, Gerard; Rana, Amer A.; Morrell, Nicholas W.

    2014-01-01

    The endothelial cell has a remarkable ability for sub-specialisation, adapted to the needs of a variety of vascular beds. The role of developmental programming versus the tissue contextual environment for this specialization is not well understood. Here we describe a hierarchy of expression of HOX genes associated with endothelial cell origin and location. In initial microarray studies, differential gene expression was examined in two endothelial cell lines: blood derived outgrowth endothelial cells (BOECs) and pulmonary artery endothelial cells. This suggested shared and differential patterns of HOX gene expression between the two endothelial lines. For example, this included a cluster on chromosome 2 of HOXD1, HOXD3, HOXD4, HOXD8 and HOXD9 that was expressed at a higher level in BOECs. Quantative PCR confirmed the higher expression of these HOXs in BOECs, a pattern that was shared by a variety of microvascular endothelial cell lines. Subsequently, we analysed publically available microarrays from a variety of adult cell and tissue types using the whole “HOX transcriptome” of all 39 HOX genes. Using hierarchical clustering analysis the HOX transcriptome was able to discriminate endothelial cells from 61 diverse human cell lines of various origins. In a separate publically available microarray dataset of 53 human endothelial cell lines, the HOX transcriptome additionally organized endothelial cells related to their organ or tissue of origin. Human tissue staining for HOXD8 and HOXD9 confirmed endothelial expression and also supported increased microvascular expression of these HOXs. Together these observations suggest a significant involvement of HOX genes in endothelial cell positional identity. PMID:24651450

  5. Human Pulmonary Endothelial Cells in Culture

    PubMed Central

    Johnson, Alice R.

    1980-01-01

    Endothelial cells were cultured from various different human vessels, including aortas, pulmonary, ovarian, and umbilical arteries, and pulmonary, ovarian, and umbilical veins. The cultured cells were identified as endothelial cells by the presence of Factor VIII antigen and antiotensin I converting enzyme (kininase II). They retained these markers for at least five passages in culture, and some cells had them for seven passages or more. Endothelial cells from the various vessels were compared with respect to their ability to metabolize angiotensins I and II and bradykinin. Cells from arteries had three to five times the angiotensin I converting enzyme activity as cells from veins. The activity of angiotensinase A (aspartyl aminopeptidase) had a similar distribution, and cells from arteries were consistently more active than cells from veins. Cultures of endothelial cells from pulmonary and umbilical vessels formed prostacyclin in response to mechanical stimulation. Media from cell monolayers that were subjected to a change of medium and gentle agitation inhibited aggregation of human platelets. This inhibitory activity was generated within 2-5 min, and it was not formed by cells that were treated with indomethacin or tranylcypromine. Addition of prostaglandin (PG)H2 to indomethacin-treated cells restored the ability to form the inhibitor, but cells treated with tranylcypromine were not responsive to PGH2. In experiments where [14C]arachidonic acid was added to the cells before stimulation, the major metabolite identified by thin-layer chromatography was 6-keto PGF1α. Thus, it appears that pulmonary endothelial cells, as well as umbilical cord cells, can form prostacyclin. In experiments comparing the ability of arterial and venous cells to form prostacyclin, arterial cells were more active than venous cells. These studies of cells from various human vessels suggest that the vascular origin of cultured endothelial cells determines how they metabolize vasoactive

  6. Endothelial Cell Stimulation by Candida albicans

    PubMed Central

    Phan, Quynh T.; Filler, Scott G.

    2013-01-01

    The opportunistic fungal pathogen, Candida albicans, enters the bloodstream and causes hematogenously disseminated infection in hospitalized patients. During the initiation of a hematogenously disseminated infection, endothelial cells are one of the first host cells to come in contact with C. albicans. Endothelial cells can significantly influence the local host response to C. albicans by expressing leukocyte adhesion molecules and pro-inflammatory cytokines. Thus, it is of interest to investigate the response of endothelial cells to C. albicans in vitro. We describe the use of real-time PCR and enzyme immunoassays to measure the effects of C. albicans on the endothelial cell production of E-selectin and tumor necrosis factor α in vitro. PMID:19089392

  7. Effects of glucocorticoids on the interaction of lymphoblastoid cells with human endothelial cells in vitro.

    PubMed

    Maca, R D; Fry, G L; Hakes, A D

    1978-08-01

    The adhesive characteristics of cultured acute lymphocytic leukemia cells (CCRF-CEM), lymphoma cells (Raji), and freshly isolated acute lymphocytic leukemia cells to human cultured endothelial cells were studied. An assay system was used whereby these neoplastic cells were allowed to interact with endothelial cells while being continuously agitated on a rocking platform. All cell lines adhered significantly to the endothelium monolayers. This process appeared not to be dependent upon intact microtubular or microfilament function. Likewise, removing surface sialic acid from either cell type did not alter this process. In contrast incubating the endothelial cells for 24 or 48 hr with dexamethasone decreased adhesiveness of either CCRF-CEM or Raji cells to the endothelial cells by approximately 40%. Incubating these cells with hydrocortisone instead of dexamethasone for 48 hr was equally as effective in altering the endothelial cell adhesiveness. The decreased adhesiveness could be blocked by cycloheximide, indicating that this altered adhesiveness of the endothelial cells involves protein synthesis, presumably of a surface protein. We suggest that this assay system may provide a means to evaluate other agents that can alter the surface characteristics of endothelial cells, which may have important implications in various disease states such as inflammation, thrombogenesis, and metastatic disease. PMID:276420

  8. Endothelial cell Ca2+ increases upon tumor cell contact and modulates cell-cell adhesion.

    PubMed Central

    Pili, R; Corda, S; Passaniti, A; Ziegelstein, R C; Heldman, A W; Capogrossi, M C

    1993-01-01

    The signal transduction mechanisms involved in tumor cell adhesion to endothelial cells are still largely undefined. The effect of metastatic murine melanoma cell and human prostate carcinoma cell contact on cytosolic [Ca2+] of bovine artery endothelial cells was examined in indo-1-loaded endothelial cell monolayers. A rapid increase in endothelial cell [Ca2+] occurred on contact with tumor cells, but not on contact with 8-microns inert beads. A similar increase in endothelial cell [Ca2+] was observed with human neutrophils or monocyte-like lymphoma cells, but not with endothelial cells, red blood cells, and melanoma cell-conditioned medium. The increase in endothelial cell [Ca2+] was not inhibited by extracellular Ca2+ removal. In contrast, endothelial cell pretreatment with thapsigargin, which releases endoplasmic reticulum Ca2+ into the cytosol and depletes this Ca2+ store site, abolished the cytosolic [Ca2+] rise upon melanoma cell contact. Endothelial cell pretreatment with the membrane-permeant form of the Ca2+ chelator bis-(O-aminophenoxyl)ethane-N,N,N',N'-tetraacetic acid blocked the increase in cytosolic [Ca2+]. Under static and dynamic flow conditions (0.46 dyn/cm2) bis-(O-aminophenoxyl)ethane-N,N,N',N'-tetraacetic acid pretreatment of bovine pulmonary artery endothelial cell monolayers inhibited melanoma cell adhesion to the endothelial cells. Thus, tumor cell contact with endothelial cells induces a rapid Ca2+ release from endothelial intracellular stores, which has a functional role in enhancing cell-cell adhesion. Images PMID:8254056

  9. Apoptotic Cells Initiate Endothelial Cell Sprouting via Electrostatic Signaling

    PubMed Central

    Weihua, Zhang; Tsan, Rachel; Schroit, Alan J.; Fidler, Isaiah J.

    2006-01-01

    Angiogenesis, the development of new blood vessels from preexisting vessels, is crucial to tissue growth, repair, and maintenance. This process begins with the formation of endothelial cell sprouts followed by the proliferation and migration of neighboring endothelial cells along the pre-formed extensions. The initiating event and mechanism of sprouting is not known. We demonstrate that the phenotypic expression of negative-charged membrane surface in apoptotic cells initiates the formation of directional endothelial cell sprouts that extend toward the dying cells by a mechanism that involves endothelial cell membrane hyperpolarization and cytoskeleton reorganization but is independent of diffusible molecules. PMID:16357162

  10. Micropatterned Structural Control Suppresses Mechanotaxis of Endothelial Cells

    PubMed Central

    Lin, Xiefan; Helmke, Brian P.

    2008-01-01

    Vascular endothelial cell migration is critical in many physiological processes including wound healing and stent endothelialization. To determine how preexisting cell morphology influences cell migration under fluid shear stress, endothelial cells were preset in an elongated morphology on micropatterned substrates, and unidirectional shear stress was applied either parallel or perpendicular to the cell elongation axis. On micropatterned 20-μm lines, cells exhibited an elongated morphology with stress fibers and focal adhesion sites aligned parallel to the lines. On 115-μm lines, cell morphology varied as a function of distance from the line edge. Unidirectional shear stress caused unpatterned cells in a confluent monolayer to exhibit triphasic mechanotaxis behavior. During the first 3 h, cell migration speed increased in a direction antiparallel to the shear stress direction. Migration speed then slowed and direction became spatially heterogeneous. Starting 11–12 h after the onset of shear stress, the unpatterned cells migrated primarily in the downstream direction, and migration speed increased significantly. In contrast, mechanotaxis was suppressed after the onset of shear stress in cells on micropatterned lines during the same time period, for the cases of both parallel and perpendicular flow. The directional persistence time was much longer for cells on the micropatterned lines, and it decreased significantly after flow onset. Migration trajectories were highly correlated among micropatterned cells within a three-cell neighborhood, and shear stress disrupted this spatially correlated migration behavior. Thus, presetting structural morphology may interfere with mechanisms of sensing local physical cues, which are critical for establishing mechanotaxis in response to hemodynamic shear stress. PMID:18586851

  11. Isolation and culture of pulmonary endothelial cells.

    PubMed

    Ryan, U S

    1984-06-01

    Methods for isolation, identification and culture of pulmonary endothelial cells are now routine. In the past, methods of isolation have used proteolytic enzymes to detach cells; thereafter, traditional methods for cell passaging have used trypsin/EDTA mixtures. Cells isolated and passaged using proteolytic enzymes have been useful in establishing the field and in verifying certain endothelial properties. However, there is a growing awareness of the role of endothelial cells in processing vasoactive substances, in responding to hormones and other agonists and in cell-cell interactions with other cell types of the vascular wall, with blood cells and with cellular products. Consequently, a new requirement has arisen for cells in vitro that maintain the differentiated properties of their counterparts in vivo. The deleterious effects of trypsin and other proteolytic enzymes commonly used in cell culture on surface structures of endothelial cells such as enzymes, receptors and junctional proteins, as well as on extracellular layers such as the glycocalyx or "endothelial fuzz," have led to the development of methods that avoid use of proteolytic enzymes at both the isolation step and during subsequent subculture. This chapter describes traditional methods for isolating pulmonary endothelial cells but emphasizes newer approaches using mechanical harvest and scale-up using microcarriers. The new methods allow maintenance of long-term, large-scale cultures of cells that retain the full complement of surface properties and that maintain the cobblestone monolayer morphology and differentiated functional properties. Methods for identification of isolated cells are therefore also considered as methods for validation of cultures during their in vitro lifespan. PMID:6090112

  12. TAK1 in brain endothelial cells mediates fever and lethargy

    PubMed Central

    Ridder, Dirk A.; Lang, Ming-Fei; Salinin, Sergei; Röderer, Jan-Peter; Struss, Marcel; Maser-Gluth, Christiane

    2011-01-01

    Systemic inflammation affects the brain, resulting in fever, anorexia, lethargy, and activation of the hypothalamus–pituitary–adrenal axis. How peripheral inflammatory signals reach the brain is still a matter of debate. One possibility is that, in response to inflammatory stimuli, brain endothelial cells in proximity to the thermoregulatory centers produce cyclooxygenase 2 (COX-2) and release prostaglandin E2, causing fever and sickness behavior. We show that expression of the MAP kinase kinase kinase TAK1 in brain endothelial cells is needed for interleukin 1β (IL-1β)–induced COX-2 production. Exploiting the selective expression of the thyroxine transporter Slco1c1 in brain endothelial cells, we generated a mouse line allowing inducible deletion of Tak1 specifically in brain endothelium. Mice lacking the Tak1 gene in brain endothelial cells showed a blunted fever response and reduced lethargy upon intravenous injection of the endogenous pyrogen IL-1β. In conclusion, we demonstrate that TAK1 in brain endothelial cells induces COX-2, most likely by activating p38 MAPK and c-Jun, and is necessary for fever and sickness behavior. PMID:22143887

  13. Isolation and characterization of ryudocan and syndecan heparan sulfate proteoglycans, core proteins, and cDNAs from a rat endothelial cell line.

    PubMed

    Shworak, N W; Kojima, T; Rosenberg, R D

    1993-03-01

    We have isolated heparan sulfate proteoglycans (HSPGs) from cloned rat microvascular endothelial cells using a combination of ion-exchange chromatography, affinity fractionation with antithrombin III (AT III), and gel filtration in denaturing solvents. The anticoagulantly active heparan sulfate proteoglycans (HSPGact) which bind tightly to AT III bear mainly anticoagulantly active heparan sulfate (HSact) whereas the anticoagulantly inactive heparan sulfate proteoglycans (HSPGinact) possess mainly anticoagulantly inactive heparan sulfate (HSinact). The core proteins of HSPGact and HSPGinact were isolated by treatment with Flavobacterium heparitinase and purification by ion-exchange chromatography. SDS-PAGE showed that both sets of core proteins exhibited three major components with M(r) of 25-, 30-, and 50-kD, respectively. Peptide mapping revealed that HSPGact and HSPGinact possess extremely similar core proteins. The primary sequences of internal peptides obtained from HSPGinact core proteins and the NH2-terminal sequence analyses of the 25-kD component from the HSPGinact core proteins demonstrate that the 30-kD component is a previously unidentified species--designated as ryudocan--with the 25-kD component representing a proteolytic degradation product; while the 50-kD component is the rat homolog of syndecan [Saunders S, Jalkanen M, O'Farrell S, Bernfield M: J Cell Biol 1989; 108:1547-1556]. Specific oligonucleotide probes were obtained for ryudocan and syndecan by PCR, and the corresponding cDNAs were isolated from a RFP-EC library. The cDNAs encode type I integral membrane proteins of 202 and 313 amino acids, respectively, which have homologous transmembrane and intracellular domains but very distinct extracellular regions. In particular, ryudocan exhibits only 3 potential glycosaminoglycan (GAG) attachment sites within the extracellular region while syndecan has 5 GAG attachment sites within the same domain. The levels of ryudocan and syndecan mRNA were

  14. Lymphatic endothelial cells actively regulate prostate cancer cell invasion.

    PubMed

    Shah, Tariq; Wildes, Flonne; Kakkad, Samata; Artemov, Dmitri; Bhujwalla, Zaver M

    2016-07-01

    Lymphatic vessels serve as the primary route for metastatic spread to lymph nodes. However, it is not clear how interactions between cancer cells and lymphatic endothelial cells (LECs), especially within hypoxic microenvironments, affect the invasion of cancer cells. Here, using an MR compatible cell perfusion assay, we investigated the role of LEC-prostate cancer (PCa) cell interaction in the invasion and degradation of the extracellular matrix (ECM) by two human PCa cell lines, PC-3 and DU-145, under normoxia and hypoxia, and determined the metabolic changes that occurred under these conditions. We observed a significant increase in the invasion of ECM by invasive PC-3 cells, but not poorly invasive DU-145 cells when human dermal lymphatic microvascular endothelial cells (HMVEC-dlys) were present. Enhanced degradation of ECM by PC-3 cells in the presence of HMVEC-dlys identified interactions between HMVEC-dlys and PCa cells influencing cancer cell invasion. The enhanced ECM degradation was partly attributed to increased MMP-9 enzymatic activity in PC-3 cells when HMVEC-dlys were in close proximity. Significantly higher uPAR and MMP-9 expression levels observed in PC-3 cells compared to DU-145 cells may be one mechanism for increased invasion and degradation of matrigel by these cells irrespective of the presence of HMVEC-dlys. Hypoxia significantly decreased invasion by PC-3 cells, but this decrease was significantly attenuated when HMVEC-dlys were present. Significantly higher phosphocholine was observed in invasive PC-3 cells, while higher glycerophosphocholine was observed in DU-145 cells. These metabolites were not altered in the presence of HMVEC-dlys. Significantly increased lipid levels and lipid droplets were observed in PC-3 and DU-145 cells under hypoxia reflecting an adaptive survival response to oxidative stress. These results suggest that in vivo, invasive cells in or near lymphatic endothelial cells are likely to be more invasive and degrade the ECM

  15. Dengue Virus Infection of Mast Cells Triggers Endothelial Cell Activation ▿

    PubMed Central

    Brown, Michael G.; Hermann, Laura L.; Issekutz, Andrew C.; Marshall, Jean S.; Rowter, Derek; Al-Afif, Ayham; Anderson, Robert

    2011-01-01

    Vascular perturbation is a hallmark of severe forms of dengue disease. We show here that antibody-enhanced dengue virus infection of primary human cord blood-derived mast cells (CBMCs) and the human mast cell-like line HMC-1 results in the release of factor(s) which activate human endothelial cells, as evidenced by increased expression of the adhesion molecules ICAM-1 and VCAM-1. Endothelial cell activation was prevented by pretreatment of mast cell-derived supernatants with a tumor necrosis factor (TNF)-specific blocking antibody, thus identifying TNF as the endothelial cell-activating factor. Our findings suggest that mast cells may represent an important source of TNF, promoting vascular endothelial perturbation following antibody-enhanced dengue virus infection. PMID:21068256

  16. Endothelial Cell Response to Fusobacterium nucleatum.

    PubMed

    Mendes, Reila Tainá; Nguyen, Daniel; Stephens, Danielle; Pamuk, Ferda; Fernandes, Daniel; Van Dyke, Thomas E; Kantarci, Alpdogan

    2016-07-01

    Vascular response is an essential aspect of an effective immune response to periodontal disease pathogens, as new blood vessel formation contributes to wound healing and inflammation. Gaining a greater understanding of the factors that affect vascular response may then contribute to future breakthroughs in dental medicine. In this study, we have characterized the endothelial cell response to the common bacterium Fusobacterium nucleatum, an important bridging species that facilitates the activity of late colonizers of the dental biofilm. Endothelial cells were infected with Fusobacterium nucleatum (strain 25586) for periods of 4, 12, 24, or 48 h. Cell proliferation and tube formation were analyzed, and expression of adhesion molecules (CD31 and CD34) and vascular endothelial growth factor (VEGF) receptors 1 and 2 was measured by fluorescence-activated cell sorter (FACS) analysis. Data indicate that F. nucleatum impaired endothelial cell proliferation and tube formation. The findings suggest that the modified endothelial cell response acts as a mechanism promoting the pathogenic progression of periodontal diseases and may potentially suggest the involvement of periodontopathogens in systemic diseases associated with periodontal inflammation. PMID:27185790

  17. Lymphatic endothelial differentiation in pulmonary lymphangioleiomyomatosis cells.

    PubMed

    Davis, Jennifer M; Hyjek, Elizabeth; Husain, Aliya N; Shen, Le; Jones, Jennifer; Schuger, Lucia A

    2013-08-01

    Pulmonary lymphangioleiomyomatosis (LAM) is a rare, low-grade neoplasm affecting almost exclusively women of childbearing age. LAM belongs to the family of perivascular epithelioid cell tumors, characterized by spindle and epithelioid cells with smooth muscle and melanocytic differentiation. LAM cells infiltrate the lungs, producing multiple, bilateral lesions rich in lymphatic channels and forming cysts, leading to respiratory insufficiency. Here we used antibodies against four lymphatic endothelial markers-podoplanin (detected by D2-40), prospero homeobox 1 (PROX1), vascular endothelial growth factor receptor 3 (VEGFR-3), and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1)-to determine whether LAM cells show lymphatic differentiation. Twelve of 12 diagnostic biopsy specimens (early-stage LAM) and 19 of 19 explants (late-stage LAM) showed immunopositivity for D2-40 in most neoplastic cells. PROX1, VEGFR-3, and LYVE1 immunoreactivity varied from scarce in the early stage to abundant in the late stage. Lymphatic endothelial, smooth muscle, and melanocytic markers were partially co-localized. These findings indicate that lymphatic endothelial differentiation is a feature of LAM and provide evidence of a previously unidentified third lineage of differentiation in this neoplasm. This study has implications for the histological diagnosis of LAM, the origin of the neoplastic cells, and potential future treatment with drugs targeting lymphangiogenesis. PMID:23609227

  18. Endothelial cells derived from human embryonic stem cells

    NASA Astrophysics Data System (ADS)

    Levenberg, Shulamit; Golub, Justin S.; Amit, Michal; Itskovitz-Eldor, Joseph; Langer, Robert

    2002-04-01

    Human embryonic stem cells have the potential to differentiate into various cell types and, thus, may be useful as a source of cells for transplantation or tissue engineering. We describe here the differentiation steps of human embryonic stem cells into endothelial cells forming vascular-like structures. The human embryonic-derived endothelial cells were isolated by using platelet endothelial cell-adhesion molecule-1 (PECAM1) antibodies, their behavior was characterized in vitro and in vivo, and their potential in tissue engineering was examined. We show that the isolated embryonic PECAM1+ cells, grown in culture, display characteristics similar to vessel endothelium. The cells express endothelial cell markers in a pattern similar to human umbilical vein endothelial cells, their junctions are correctly organized, and they have high metabolism of acetylated low-density lipoprotein. In addition, the cells are able to differentiate and form tube-like structures when cultured on matrigel. In vivo, when transplanted into SCID mice, the cells appeared to form microvessels containing mouse blood cells. With further studies, these cells could provide a source of human endothelial cells that could be beneficial for potential applications such as engineering new blood vessels, endothelial cell transplantation into the heart for myocardial regeneration, and induction of angiogenesis for treatment of regional ischemia.

  19. Role of the Retinal Vascular Endothelial Cell in Ocular Disease

    PubMed Central

    Bharadwaj, Arpita S.; Appukuttan, Binoy; Wilmarth, Phillip A.; Pan, Yuzhen; Stempel, Andrew J.; Chipps, Timothy J.; Benedetti, Eric E.; Zamora, David O.; Choi, Dongseok; David, Larry L.; Smith, Justine R.

    2012-01-01

    Retinal endothelial cells line the arborizing microvasculature that supplies and drains the neural retina. The anatomical and physiological characteristics of these endothelial cells are consistent with nutritional requirements and protection of a tissue critical to vision. On the one hand, the endothelium must ensure the supply of oxygen and other nutrients to the metabolically active retina, and allow access to circulating cells that maintain the vasculature or survey the retina for the presence of potential pathogens. On the other hand, the endothelium contributes to the blood-retinal barrier that protects the retina by excluding circulating molecular toxins, microorganisms, and pro-inflammatory leukocytes. Features required to fulfill these functions may also predispose to disease processes, such as retinal vascular leakage and neovascularization, and trafficking of microbes and inflammatory cells. Thus, the retinal endothelial cell is a key participant in retinal ischemic vasculopathies that include diabetic retinopathy and retinopathy of prematurity, and retinal inflammation or infection, as occurs in posterior uveitis. Using gene expression and proteomic profiling, it has been possible to explore the molecular phenotype of the human retinal endothelial cell and contribute to understanding of the pathogenesis of these diseases. In addition to providing support for the involvement of well-characterized endothelial molecules, profiling has the power to identify new players in retinal pathologies. Findings may have implications for the design of new biological therapies. Additional progress in this field is anticipated as other technologies, including epigenetic profiling methods, whole transcriptome shotgun sequencing, and metabolomics, are used to study the human retinal endothelial cell. PMID:22982179

  20. Endothelial progenitor cells in hematologic malignancies

    PubMed Central

    Saulle, Ernestina; Castelli, Germana; Pelosi, Elvira

    2016-01-01

    Studies carried out in the last years have improved the understanding of the cellular and molecular mechanisms controlling angiogenesis during adult life in normal and pathological conditions. Some of these studies have led to the identification of some progenitor cells that sustain angiogenesis through indirect, paracrine mechanisms (hematopoietic angiogenic cells) and through direct mechanisms, i.e., through their capacity to generate a progeny of phenotypically and functionally competent endothelial cells [endothelial colony forming cells (ECFCs)]. The contribution of these progenitors to angiogenetic processes under physiological and pathological conditions is intensively investigated. Angiogenetic mechanisms are stimulated in various hematological malignancies, including chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma, resulting in an increased angiogenesis that contributes to disease progression. In some of these conditions there is preliminary evidence that some endothelial cells could derive from the malignant clone, thus leading to the speculation that the leukemic cell derives from the malignant transformation of a hemangioblastic progenitor, i.e., of a cell capable of differentiation to the hematopoietic and to the endothelial cell lineages. Our understanding of the mechanisms underlying increased angiogenesis in these malignancies not only contributed to a better knowledge of the mechanisms responsible for tumor progression, but also offered the way for the discovery of new therapeutic targets. PMID:27583252

  1. Endothelial progenitor cells in hematologic malignancies.

    PubMed

    Testa, Ugo; Saulle, Ernestina; Castelli, Germana; Pelosi, Elvira

    2016-01-01

    Studies carried out in the last years have improved the understanding of the cellular and molecular mechanisms controlling angiogenesis during adult life in normal and pathological conditions. Some of these studies have led to the identification of some progenitor cells that sustain angiogenesis through indirect, paracrine mechanisms (hematopoietic angiogenic cells) and through direct mechanisms, i.e., through their capacity to generate a progeny of phenotypically and functionally competent endothelial cells [endothelial colony forming cells (ECFCs)]. The contribution of these progenitors to angiogenetic processes under physiological and pathological conditions is intensively investigated. Angiogenetic mechanisms are stimulated in various hematological malignancies, including chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma, resulting in an increased angiogenesis that contributes to disease progression. In some of these conditions there is preliminary evidence that some endothelial cells could derive from the malignant clone, thus leading to the speculation that the leukemic cell derives from the malignant transformation of a hemangioblastic progenitor, i.e., of a cell capable of differentiation to the hematopoietic and to the endothelial cell lineages. Our understanding of the mechanisms underlying increased angiogenesis in these malignancies not only contributed to a better knowledge of the mechanisms responsible for tumor progression, but also offered the way for the discovery of new therapeutic targets. PMID:27583252

  2. Digital imaging of diabetic endothelial cells

    NASA Astrophysics Data System (ADS)

    Paltauf-Doburzynska, Jolanta; Kohlwein, Sepp D.; Graier, Wolfgang F.

    2001-05-01

    Endothelial cells release factors that regulate dilatation and contraction of the vessels. They play an important role in modulating both the inflammatory response and vasomotor abnormalities that occur in coronary artery diseases. This endothelial function is associated with changes of intracellular Ca2+ concentration. For this study we used spatially and temporally resolved measurements of local Ca2+ concentration in human endothelial cells cultured in high glucose containing medium. Deconvolution techniques procedure allowed determination of intracellular Ca2+ concentration and its distribution into cellular compartments. We also used a confocal microscope for visualization of intracellular compartments (endoplasmatic reticulum, mitochondria) under normal and pathological conditions. We showed that the interrupted connection between superficial compartments and membrane channels is already the beginning of the cell damage in diabetes.

  3. Inhibition of the focal adhesion kinase and vascular endothelial growth factor receptor-3 interaction leads to decreased survival in human neuroblastoma cell lines.

    PubMed

    Beierle, Elizabeth A; Ma, Xiaojie; Stewart, Jerry E; Megison, Michael; Cance, William G; Kurenova, Elena V

    2014-03-01

    Neuroblastoma continues to be a devastating childhood solid tumor and is responsible for over 15% of all childhood cancer-related deaths. Focal adhesion kinase (FAK) and vascular endothelial growth factor receptor-3 (VEGFR-3) are protein tyrosine kinases that are overexpressed in a number of human cancers, including neuroblastoma. These two kinases can directly interact and provide survival signals to cancer cells. In this study, we utilized siRNA to VEGFR-3 to demonstrate the biologic importance of this kinase in neuroblastoma cell survival. We also used confocal microscopy and immunoprecipitation to show that FAK and VEGFR-3 bind in neuroblastoma. Finally, employing a 12-amino-acid peptide (AV3) specific to VEGFR-3, we showed that the colocalization between FAK and VEGFR-3 could be disrupted, and that disruption resulted in decreased neuroblastoma cell survival. These studies provide insight to the FAK-VEGFR-3 interaction in neuroblastoma and demonstrate its importance in this tumor type. Focusing upon the FAK-VEGFR-3 interaction may provide a novel therapeutic target for the development of new strategies for treatment of neuroblastoma. PMID:23065847

  4. Mechanical property quantification of endothelial cells using scanning acoustic microscopy

    NASA Astrophysics Data System (ADS)

    Shelke, A.; Brand, S.; Kundu, T.; Bereiter-Hahn, J.; Blase, C.

    2012-04-01

    The mechanical properties of cells reflect dynamic changes of cellular organization which occur during physiologic activities like cell movement, cell volume regulation or cell division. Thus the study of cell mechanical properties can yield important information for understanding these physiologic activities. Endothelial cells form the thin inner lining of blood vessels in the cardiovascular system and are thus exposed to shear stress as well as tensile stress caused by the pulsatile blood flow. Endothelial dysfunction might occur due to reduced resistance to mechanical stress and is an initial step in the development of cardiovascular disease like, e.g., atherosclerosis. Therefore we investigated the mechanical properties of primary human endothelial cells (HUVEC) of different age using scanning acoustic microscopy at 1.2 GHz. The HUVECs are classified as young (tD < 90 h) and old (tD > 90 h) cells depending upon the generation time for the population doubling of the culture (tD). Longitudinal sound velocity and geometrical properties of cells (thickness) were determined using the material signature curve V(z) method for variable culture condition along spatial coordinates. The plane wave technique with normal incidence is assumed to solve two-dimensional wave equation. The size of the cells is modeled using multilayered (solid-fluid) system. The propagation of transversal wave and surface acoustic wave are neglected in soft matter analysis. The biomechanical properties of HUVEC cells are quantified in an age dependent manner.

  5. Islet Endothelial Cells Derived From Mouse Embryonic Stem Cells.

    PubMed

    Jain, Neha; Lee, Eun Jung

    2016-01-01

    The islet endothelium comprises a specialized population of islet endothelial cells (IECs) expressing unique markers such as nephrin and α-1 antitrypsin (AAT) that are not found in endothelial cells in surrounding tissues. However, due to difficulties in isolating and maintaining a pure population of these cells, the information on these islet-specific cells is currently very limited. Interestingly, we have identified a large subpopulation of endothelial cells exhibiting IEC phenotype, while deriving insulin-producing cells from mouse embryonic stem cells (mESCs). These cells were identified by the uptake of low-density lipoprotein (LDL) and were successfully isolated and subsequently expanded in endothelial cell culture medium. Further analysis demonstrated that the mouse embryonic stem cell-derived endothelial cells (mESC-ECs) not only express classical endothelial markers, such as platelet endothelial cell adhesion molecule (PECAM1), thrombomodulin, intercellular adhesion molecule-1 (ICAM-1), and endothelial nitric oxide synthase (eNOS) but also IEC-specific markers such as nephrin and AAT. Moreover, mESC-ECs secrete basement membrane proteins such as collagen type IV, laminin, and fibronectin in culture and form tubular networks on a layer of Matrigel, demonstrating angiogenic activity. Further, mESC-ECs not only express eNOS, but also its eNOS expression is glucose dependent, which is another characteristic phenotype of IECs. With the ability to obtain highly purified IECs derived from pluripotent stem cells, it is possible to closely examine the function of these cells and their interaction with pancreatic β-cells during development and maturation in vitro. Further characterization of tissue-specific endothelial cell properties may enhance our ability to formulate new therapeutic angiogenic approaches for diabetes. PMID:25751085

  6. PC12 Cells Differentiate into Chromaffin Cell-Like Phenotype in Coculture with Adrenal Medullary Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Mizrachi, Yaffa; Naranjo, Jose R.; Levi, Ben-Zion; Pollard, Harvey B.; Lelkes, Peter I.

    1990-08-01

    Previously we described specific in vitro interactions between PC12 cells, a cloned, catecholamine-secreting pheochromocytoma cell line derived from the rat adrenal medulla, and bovine adrenal medullary endothelial cells. We now demonstrate that these interactions induce the PC12 cells to acquire physical and biochemical characteristics reminiscent of chromaffin cells. Under coculture conditions involving direct cell-cell contact, the endothelial cells and the PC12 cells reduced their rates of proliferation; upon prolonged coculture PC12 cells clustered into nests of cells similar to the organization of chromaffin cells seen in vivo. Within 3 days in coculture with endothelial cells, but not with unrelated control cells, PC12 cells synthesized increased levels of [Met]enkephalin. In addition, PC12 cells, growing on confluent endothelial monolayers, failed to extend neurites in response to nerve growth factor. Neither medium conditioned by endothelial cells nor fixed endothelial cells could by themselves induce all of these different phenomena in the PC12 cells. These results suggest that under coculture conditions PC12 cells change their state of differentiation toward a chromaffin cell-like phenotype. The rapid, transient increase in the expression of the protooncogene c-fos suggests that the mechanism(s) inducing the change in the state of differentiation in PC12 cells in coculture with the endothelial cells may be distinct from that described for the differentiation of PC12 cells--e.g., by glucocorticoids. We propose that similar interactions between endothelial cells and chromaffin cell precursors may occur during embryonic development and that these interactions might be instrumental for the organ-specific differentiation of the adrenal medulla in vivo.

  7. Circulating endothelial cells in cardiovascular disease.

    PubMed

    Boos, Christopher J; Lip, Gregory Y H; Blann, Andrew D

    2006-10-17

    Quantification of circulating endothelial cells (CECs) in peripheral blood is developing as a novel and reproducible method of assessing endothelial damage/dysfunction. The CECs are thought to be mature cells that have detached from the intimal monolayer in response to endothelial injury and are a different cell population to endothelial progenitor cells (EPCs). The EPCs are nonleukocytes derived from the bone marrow that are believed to have proliferative potential and may be important in vascular regeneration. Currently accepted methods of CEC quantification include the use of immunomagnetic bead separation (with cell counting under fluorescence microscopy) and flow cytometry. Several recent studies have shown increased numbers of CECs in cardiovascular disease and its risk factors, such as unstable angina, acute myocardial infarction, stroke, diabetes mellitus, and critical limb ischemia, but no change in stable intermittent claudication, essential hypertension, or atrial fibrillation. Furthermore, CEC quantification at 48 h after acute myocardial infarction has been shown to be an accurate predictor of major adverse coronary events and death at both 1 month and 1 year. This article presents an overview of the pathophysiology of CECs in the setting of cardiovascular disease and a brief comparison with EPCs. PMID:17045885

  8. Effects of inhibitors of vascular endothelial growth factor receptor 2 and downstream pathways of receptor tyrosine kinases involving phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin or mitogen-activated protein kinase in canine hemangiosarcoma cell lines.

    PubMed

    Adachi, Mami; Hoshino, Yuki; Izumi, Yusuke; Sakai, Hiroki; Takagi, Satoshi

    2016-07-01

    Canine hemangiosarcoma (HSA) is a progressive malignant neoplasm with no current effective treatment. Previous studies showed that receptor tyrosine kinases and molecules within their downstream pathways involving phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (m-TOR) or mitogen-activated protein kinase (MAPK) were overexpressed in canine, human, and murine tumors, including HSA. The present study investigated the effects of inhibitors of these pathways in canine splenic and hepatic HSA cell lines using assays of cell viability and apoptosis. Inhibitors of the MAPK pathway did not affect canine HSA cell viability. However, cell viability was significantly reduced by exposure to inhibitors of vascular endothelial growth factor receptor 2 and the PI3K/Akt/m-TOR pathway; these inhibitors also induced apoptosis in these cell lines. These results suggest that these inhibitors reduce the proliferation of canine HSA cells by inducing apoptosis. Further study of these inhibitors, using xenograft mouse models of canine HSA, are warranted to explore their potential for clinical application. PMID:27408334

  9. Functional impairment of endothelial cells by the antimycotic amphotericin B.

    PubMed

    Pelzmann, Brigitte; Di Giuro, Cristiana M L; Zorn-Pauly, Klaus; Rossmann, Christine; Hallström, Seth; Groschner, Klaus; Fameli, Nicola

    2016-03-25

    We set out to determine the membrane potential (Vm) of the endothelial cell line EA.hy926 and its sensitivity to the antimycotic amphotericin B (AmB), a commonly used antifungal component in cell culture media. We measured the endothelial Vm under various experimental conditions by patch clamp technique and found that Vm of AmB-treated cells is (-12.1 ± 9.3) mV, while in AmB-untreated (control) cells it is (-57.1 ± 4.1) mV. In AmB-free extracellular solutions, Vm recovered toward control levels and this gain in Vm rapidly dissipated upon re-addition of AmB, demonstrating a rapid and reversible effect of AmB on endothelial Vm. The consequences of AmB dependent alterations in endothelial transmembrane potential were tested at the levels of Ca(2+) signaling, of nucleotide concentrations, and energy metabolism. In AmB-treated cells we found substantially reduced Ca(2+) entry (to about 60% of that in control cells) in response to histamine induced endoplasmic reticulum (ER) Ca(2+) depletion, and diminished the ATP-to-ADP ratio (by >30%). Our data demonstrate a marked and experimentally relevant dependence of basic functional parameters of cultured endothelial cells on the presence of the ionophoric antimycotic AmB. The profound and reversible effects of the widely used culture media component AmB need careful consideration when interpreting experimental data obtained under respective culture conditions. PMID:26902113

  10. Regulation of lysophosphatidic acid-stimulated tyrosine phosphorylation of mitogen-activated protein kinase by protein kinase C- and pertussis toxin-dependent pathways in the endothelial cell line EAhy 926.

    PubMed Central

    McLees, A; Graham, A; Malarkey, K; Gould, G W; Plevin, R

    1995-01-01

    In the endothelial cell line EAhy 926, 1-oleoyl-lysophosphatidic acid (LPA) stimulated the tyrosine phosphorylation of the pp42 isoform of mitogen-activated protein (MAP) kinase. Maximum phosphorylation was observed within 5 min of LPA addition, but the response was sustained for up to 120 min. Re-addition of LPA after 60 min stimulated a further sustained increase in the tyrosine phosphorylation of MAP kinase. In cells pretreated with phorbol 12-myristate 13-acetate (PMA; 24 h) or preincubated with the protein kinase C inhibitor Ro-318220, LPA-induced tyrosine phosphorylation of pp42 MAP kinase was substantially reduced at 2 min but potentiated at 60 min. Ro-318220 in combination with either PMA or pertussis toxin pretreatment abolished the LPA response at all time points, suggesting an involvement of protein kinase C in the pertussis toxin-sensitive part of the pathway. Agents which raised intracellular cyclic AMP levels did not affect the initial phase of LPA-stimulated MAP kinase activation, but abolished the late phase. However, this effect was prevented by Ro-318220, implicating a greater role for protein kinase C than protein kinase A in the regulation of sustained MAP kinase responses. LPA stimulated an increase in the tyrosine phosphorylation of focal adhesion kinase pp125 (pp125FAK) in EAhy 926 cells which was both protein kinase C- and pertussis toxin-independent. These results are discussed in terms of the pathways regulating both MAP kinase and pp125FAK in response to LPA in the EAhy 926 endothelial cells line. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7741705

  11. Regulation of lysophosphatidic acid-stimulated tyrosine phosphorylation of mitogen-activated protein kinase by protein kinase C- and pertussis toxin-dependent pathways in the endothelial cell line EAhy 926.

    PubMed

    McLees, A; Graham, A; Malarkey, K; Gould, G W; Plevin, R

    1995-05-01

    In the endothelial cell line EAhy 926, 1-oleoyl-lysophosphatidic acid (LPA) stimulated the tyrosine phosphorylation of the pp42 isoform of mitogen-activated protein (MAP) kinase. Maximum phosphorylation was observed within 5 min of LPA addition, but the response was sustained for up to 120 min. Re-addition of LPA after 60 min stimulated a further sustained increase in the tyrosine phosphorylation of MAP kinase. In cells pretreated with phorbol 12-myristate 13-acetate (PMA; 24 h) or preincubated with the protein kinase C inhibitor Ro-318220, LPA-induced tyrosine phosphorylation of pp42 MAP kinase was substantially reduced at 2 min but potentiated at 60 min. Ro-318220 in combination with either PMA or pertussis toxin pretreatment abolished the LPA response at all time points, suggesting an involvement of protein kinase C in the pertussis toxin-sensitive part of the pathway. Agents which raised intracellular cyclic AMP levels did not affect the initial phase of LPA-stimulated MAP kinase activation, but abolished the late phase. However, this effect was prevented by Ro-318220, implicating a greater role for protein kinase C than protein kinase A in the regulation of sustained MAP kinase responses. LPA stimulated an increase in the tyrosine phosphorylation of focal adhesion kinase pp125 (pp125FAK) in EAhy 926 cells which was both protein kinase C- and pertussis toxin-independent. These results are discussed in terms of the pathways regulating both MAP kinase and pp125FAK in response to LPA in the EAhy 926 endothelial cells line. PMID:7741705

  12. Regulation of endothelial cell differentiation and specification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The circulatory system is the first organ system to develop in the vertebrate embryo and is critical throughout gestation for the delivery of oxygen and nutrients to, as well as removal of metabolic waste products from, growing tissues. Endothelial cells, which constitute the luminal layer of all bl...

  13. [Endothelial cells in the blood in psoriasis].

    PubMed

    Sochorova, R; Sinka, L; Svecova, D; Benova, B; Rybarova, L

    2000-01-01

    The authors have examined the changes in the amount of endothelial cells in vascular bed in psoriatic patients, since one of the basic signs of pathogenesis of psoriasis is represented by angiogenesis. The authors have used the method of quantitative evaluation of endothelaemia. PMID:11187061

  14. The control of vascular endothelial cell injury.

    PubMed

    Murota, S; Morita, I; Suda, N

    1990-01-01

    The mechanism by which MCI-186 showed a potent cytoprotective effect on the in vitro endothelial cell injury due to 15-HPETE was studied. Stimulation of human leukocytes with various chemical mediators such as TPA, f-Met-Leu-Phe, LTB4, etc. elicited the production of active oxygens, which could be detected by luminol-dependent chemiluminescence. Among the chemical mediators tested, TPA elicited the chemiluminescence the most, and f-Met-Leu-Phe and LTB4 came next. When the leukocytes were directly placed on a monolayer of cultured endothelial cells, followed by stimulating the leukocytes with TPA, severe endothelial cell injury was observed. The effect of TPA was dose dependent. There was good correlation between the active oxygen releasing activity and the cytotoxic activity. When the leukocytes were placed on a filter which was set apart from the monolayer of endothelial cell in a culture dish, and stimulated the leukocytes with TPA, no cytotoxicity was observed. These data strongly suggest that the substance responsible for the cytotoxicity must be a very labile and short-lived substance, presumably active oxygens. On the other hand, MCI-186 was found to have a complete quenching activity to the chemiluminescence due to active oxygens in the TPA-leukocyte system. Taken together, these factors indicate that the potent cytoprotective effect of MCI-186 may be due to its specific radical scavenging activity. PMID:2248437

  15. Proteoglycans from human umbilical vein endothelial cells.

    PubMed

    Griesmacher, A; Hennes, R; Keller, R; Greiling, H

    1987-10-01

    Human umbilical vein endothelial cells were incubated with [35S]sulphate and investigated for their proteoglycan production. By gel chromatography, ion-exchange chromatography and CsCl density-gradient centrifugation we obtained preparative amounts of the endothelial proteoheparan sulphate HSI and of proteochondroitin sulphate from the conditioned medium of mass-cultured human umbilical vein endothelial cells. Approximately 90% of the 35S-labeled material in the endothelial cell conditioned medium was proteochondroitin sulphate. This molecule, with a molecular mass of 180-200 kDa, contains four side-chains of 35-40 kDa and a core protein of 35-40 kDa. Two proteoheparan sulphate forms (HSI and HSII) from the conditioned medium were distinguished by molecular mass and transport kinetics from the cell layer to the medium in pulse-chase experiments. One major form (HSI), with an approximate molecular mass of 160-200 kDa a core protein of 55-60 kDa and three to four polysaccharide side-chains of 35 kDa each, was found enriched in the cellular membrane pellet. Another proteoheparan sulphate (HSII), with polysaccharide moieties of 20 kDa, is enriched in the subendothelial matrix (substratum). PMID:2959475

  16. Novel role of lactosylceramide in vascular endothelial growth factor-mediated angiogenesis in human endothelial cells.

    PubMed

    Rajesh, Mohanraj; Kolmakova, Antonina; Chatterjee, Subroto

    2005-10-14

    Vascular endothelial growth factor (VEGF) has been implicated in angiogenesis associated with coronary heart disease, vascular complications in diabetes, inflammatory vascular diseases, and tumor metastasis. The mechanism of VEGF-driven angiogenesis involving glycosphingolipids such as lactosylceramide (LacCer), however, is not known. To demonstrate the involvement of LacCer in VEGF-induced angiogenesis, we used small interfering RNA (siRNA)-mediated silencing of LacCer synthase expression (GalT-V) in human umbilical vein endothelial cells. This gene silencing markedly inhibited VEGF-induced platelet endothelial cell adhesion molecule-1 (PECAM-1) expression and angiogenesis. Second, we used D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP), an inhibitor of LacCer synthase and glucosylceramide synthase, that significantly mitigated VEGF-induced PECAM-1 expression and angiogenesis. Interestingly, these phenotypic changes were reversed by LacCer but not by structurally related compounds such as glucosylceramide, digalactosylceramide, and ceramide. In a human mesothelioma cell line (REN) that lacks the endogenous expression of PECAM-1, VEGF/LacCer failed to stimulate PECAM-1 expression and tube formation/angiogenesis. In REN cells expressing human PECAM-1 gene/protein, however, both VEGF and LacCer-induced PECAM-1 protein expression and tube formation/angiogenesis. In fact, VEGF-induced but not LacCer-induced angiogenesis was mitigated by SU-1498, a VEGF receptor tyrosine kinase inhibitor. Also, VEGF/LacCer-induced PECAM-1 expression and angiogenesis was mitigated by protein kinase C and phospholipase A2 inhibitors. These results indicate that LacCer generated in VEGF-treated endothelial cells may serve as an important signaling molecule for PECAM-1 expression and in angiogenesis. This finding and the reagents developed in our report may be useful as anti-angiogenic drugs for further studies in vitro and in vivo. PMID:16151023

  17. Platelet endothelial cell adhesion molecule-1 and mechanotransduction in vascular endothelial cells.

    PubMed

    Fujiwara, K

    2006-04-01

    Endothelial cells are known to respond to mechanical forces such as fluid shear stress and cyclic stretch, but elucidating the mechanism for mechanosensing has been difficult. Experimental data indicate that there are probably several sensing mechanisms. We have recently proposed a novel mechanoresponse mechanism that involves platelet endothelial cell adhesion molecule-1 (PECAM-1). When endothelial cells are stimulated by fluid shear stress, PECAM-1 is tyrosine phosphorylated and activates the extracellular signal-regulated kinase 1 and 2 (ERK1/2) signalling cascade. The same signalling events occurred when we applied pulling force directly on PECAM-1 on the endothelial cell surface using magnetic beads coated with antibodies against the external domain of PECAM-1. These results appear to indicate that PECAM-1 is a mechanotransduction molecule. To our knowledge, this is the first mammalian molecule that is shown to respond to mechanical force directly exerted to it. PMID:16594905

  18. V-ATPase regulates communication between microvascular endothelial cells and metastatic cells.

    PubMed

    Sennoune, S R; Arutunyan, A; del Rosario, C; Castro-Marin, R; Hussain, F; Martinez-Zaguilan, R

    2014-01-01

    To metastasize distant organs, tumor cells and endothelial cells lining the blood vessels must crosstalk. The nature of this communication that allows metastatic cells to intravasate and travel through the circulation and to extravasate to colonize different organs is poorly understood. In this study, we evaluated one of the first steps in this process—the proximity and physical interaction of endothelial and metastatic cells. To do this, we developed a cell separator chamber that allows endothelial and metastatic cells to grow side by side. We have shown in our previous studies that V-ATPases at the cell surface (pmV-ATPase) are involved in angiogenesis and metastasis. Therefore, we hypothesized that the physical proximity/interaction between endothelial and metastatic cells expressing pmV-ATPase will increase its activity in both cell types, and such activity in turn will increase pmV-ATPase expression on the membranes of both cell types. To determine pmV-ATPase activity we measured the proton fluxes (JH+) across the cell membrane. Our data indicated that interaction between endothelial and metastatic cells elicited a significant increase of JH+ via pmV-ATPase in both cell types. Bafilomycin, a V-ATPase inhibitor, significantly decrease JH+. In contrast, JH+ of the non-metastatic cells were not affected by the endothelial cells and vice-versa. Altogether, our data reveal that one of the early consequences of endothelial and metastatic cell interaction is an increase in pmV-ATPase that helps to acidify the extracellular medium and favors protease activity. These data emphasize the significance of the acidic tumor microenvironment enhancing a metastatic and invasive phenotype. PMID:24606724

  19. Vascular endothelial growth factor C promotes survival of retinal vascular endothelial cells via vascular endothelial growth factor receptor‐2

    PubMed Central

    Zhao, Bojun; Smith, Gill; Cai, Jun; Ma, Aihua; Boulton, Mike

    2007-01-01

    Aim To determine vascular endothelial growth factor C (VEGF‐C) expression in retinal endothelial cells, its antiapoptotic potential and its putative role in diabetic retinopathy. Method Cultured retinal endothelial cells and pericytes were exposed to tumour necrosis factor (TNF)α and VEGF‐C expression determined by reverse transcriptase‐polymerase chain reaction. Secreted VEGF‐C protein levels in conditioned media from endothelial cells were examined by western blotting analysis. The ability of VEGF‐C to prevent apoptosis induced by TNFα or hyperglycaemia in endothelial cells was assessed by flow cytometry. The expression of VEGF‐C in diabetic retinopathy was studied by immunohistochemistry of retinal tissue. Result VEGF‐C was expressed by both vascular endothelial cells and pericytes. TNFα up regulated both VEGF‐C and vascular endothelial growth factor receptor‐2 (VEGFR)‐2 expression in endothelial cells in a dose‐dependent manner, but had no effect on VEGFR‐3. Flow cytometry results showed that VEGF‐C prevented endothelial cell apoptosis induced by TNFα and hyperglycaemia and that the antiapoptotic effect was mainly via VEGFR‐2. In pericytes, the expression of VEGF‐C mRNA remained stable on exogenous TNFα treatment. VEGF‐C immunostaining was increased in retinal vessels in specimens with diabetes compared with retinal specimens from controls without diabetes. Conclusion In retinal endothelial cells, TNFα stimulates the expression of VEGF‐C, which in turn protects endothelial cells from apoptosis induced by TNFα or hyperglycaemia via VEGFR‐2 and thus helps sustain retinal neovascularisation. PMID:16943230

  20. Cilostazol strengthens barrier integrity in brain endothelial cells.

    PubMed

    Horai, Shoji; Nakagawa, Shinsuke; Tanaka, Kunihiko; Morofuji, Yoichi; Couraud, Pierre-Oliver; Deli, Maria A; Ozawa, Masaki; Niwa, Masami

    2013-03-01

    We studied the effect of cilostazol, a selective inhibitor of phosphodiesterase 3, on barrier functions of blood-brain barrier (BBB)-related endothelial cells, primary rat brain capillary endothelial cells (RBEC), and the immortalized human brain endothelial cell line hCMEC/D3. The pharmacological potency of cilostazol was also evaluated on ischemia-related BBB dysfunction using a triple co-culture BBB model (BBB Kit™) subjected to 6-h oxygen glucose deprivation (OGD) and 3-h reoxygenation. There was expression of phosphodiesterase 3B mRNA in RBEC, and a significant increase in intracellular cyclic AMP (cAMP) content was detected in RBEC treated with both 1 and 10 μM cilostazol. Cilostazol increased the transendothelial electrical resistance (TEER), an index of barrier tightness of interendothelial tight junctions (TJs), and decreased the endothelial permeability of sodium fluorescein through the RBEC monolayer. The effects on these barrier functions were significantly reduced in the presence of protein kinase A (PKA) inhibitor H-89. Microscopic observation revealed smooth and even localization of occludin immunostaining at TJs and F-actin fibers at the cell borders in cilostazol-treated RBEC. In hCMEC/D3 cells treated with 1 and 10 μM cilostazol for 24 and 96 h, P-glycoprotein transporter activity was increased, as assessed by rhodamine 123 accumulation. Cilostazol improved the TEER in our triple co-culture BBB model with 6-h OGD and 3-h reoxygenation. As cilostazol stabilized barrier integrity in BBB-related endothelial cells, probably via cAMP/PKA signaling, the possibility that cilostazol acts as a BBB-protective drug against cerebral ischemic insults to neurons has to be considered. PMID:23224787

  1. Phospholipid composition of cultured human endothelial cells.

    PubMed

    Murphy, E J; Joseph, L; Stephens, R; Horrocks, L A

    1992-02-01

    Detailed analyses of the phospholipid compositions of cultured human endothelial cells are reported here. No significant differences were found between the phospholipid compositions of cells from human artery, saphenous and umbilical vein. However, due to the small sample sizes, relatively large standard deviations for some of the phospholipid classes were observed. A representative composition of endothelial cells is: phosphatidylcholine 36.6%, choline plasmalogen 3.7%, phosphatidylethanolamine 10.2%, ethanolamine plasmalogen 7.6%, sphingomyelin 10.8%, phosphatidylserine 7.1%, lysophosphatidylcholine 7.5%, phosphatidylinositol 3.1%, lysophosphatidylethanolamine 3.6%, phosphatidylinositol 4,5-bisphosphate 1.8%, phosphatidic acid 1.9%, phosphatidylinositol 4-phosphate 1.5%, and cardiolipin 1.9%. The cells possess high choline plasmalogen and lysophosphatidylethanolamine contents. The other phospholipids are within the normal biological ranges expected. Phospholipids were separated by high-performance liquid chromatography and quantified by lipid phosphorus assay. PMID:1315902

  2. Functional CB1 cannabinoid receptors in human vascular endothelial cells.

    PubMed Central

    Liu, J; Gao, B; Mirshahi, F; Sanyal, A J; Khanolkar, A D; Makriyannis, A; Kunos, G

    2000-01-01

    Cannabinoid CB1 receptor mRNA was detected using reverse transcription-polymerase chain reaction (RT-PCR) in endothelial cells from human aorta and hepatic artery and in the ECV304 cell line derived from human umbilical vein endothelial cells. CB1 receptor-binding sites were detected by the high-affinity antagonist radioligand [(125)I]AM-251. In ECV304 cells, both the highly potent synthetic cannabinoid agonist HU-210 and the endogenous ligand anandamide induce activation of mitogen-activated protein (MAP) kinase, and the effect of HU-210 was completely blocked, whereas the effect of anandamide was partially inhibited by SR141716A, a selective CB1 receptor antagonist. Transfection of ECV304 cells with CB1 receptor antisense, but not sense, oligonucleotides caused the same pattern of inhibition as SR141716A. This provides more definitive evidence for the involvement of CB1 receptors in MAP kinase activation and suggests that anandamide may also activate MAP kinase via an additional, CB1 receptor-independent, SR141716A-resistant mechanism. The MAP kinase activation by anandamide in ECV304 cells requires genistein-sensitive tyrosine kinases and protein kinase C (PKC), and anandamide also activates p38 kinase and c-Jun kinase. These findings indicate that CB1 receptors located in human vascular endothelium are functionally coupled to the MAP kinase cascade. Activation of protein kinase cascades by anandamide may be involved in the modulation of endothelial cell growth and proliferation. PMID:10698714

  3. Modeling human endothelial cell transformation in vascular neoplasias

    PubMed Central

    Wen, Victoria W.; MacKenzie, Karen L.

    2013-01-01

    Endothelial cell (EC)-derived neoplasias range from benign hemangioma to aggressive metastatic angiosarcoma, which responds poorly to current treatments and has a very high mortality rate. The development of treatments that are more effective for these disorders will be expedited by insight into the processes that promote abnormal proliferation and malignant transformation of human ECs. The study of primary endothelial malignancy has been limited by the rarity of the disease; however, there is potential for carefully characterized EC lines and animal models to play a central role in the discovery, development and testing of molecular targeted therapies for vascular neoplasias. This review describes molecular alterations that have been identified in EC-derived neoplasias, as well as the processes that underpin the immortalization and tumorigenic conversion of ECs. Human EC lines, established through the introduction of defined genetic elements or by culture of primary tumor tissue, are catalogued and discussed in relation to their relevance as models of vascular neoplasia. PMID:24046386

  4. Reduced Ang2 expression in aging endothelial cells.

    PubMed

    Hohensinner, P J; Ebenbauer, B; Kaun, C; Maurer, G; Huber, K; Wojta, J

    2016-06-01

    Aging endothelial cells are characterized by increased cell size, reduced telomere length and increased expression of proinflammatory cytokines. In addition, we describe here that aging reduces the migratory distance of endothelial cells. Furthermore, we observe an increase of the quiescence protein Ang1 and a decrease of the endothelial activation protein Ang2 upon aging. Supplementing Ang2 to aged endothelial cells restored their migratory capacity. We conclude that aging shifts the balance of the Ang1/Ang2 network favouring a quiescent state. Activation of endothelial cells in aging might be necessary to enhance wound healing capacities. PMID:27137842

  5. Isolation of Murine Embryonic Hemogenic Endothelial Cells.

    PubMed

    Fang, Jennifer S; Gritz, Emily C; Marcelo, Kathrina L; Hirschi, Karen K

    2016-01-01

    The specification of hemogenic endothelial cells from embryonic vascular endothelium occurs during brief developmental periods within distinct tissues, and is necessary for the emergence of definitive HSPC from the murine extra embryonic yolk sac, placenta, umbilical vessels, and the embryonic aorta-gonad-mesonephros (AGM) region. The transient nature and small size of this cell population renders its reproducible isolation for careful quantification and experimental applications technically difficult. We have established a fluorescence-activated cell sorting (FACS)-based protocol for simultaneous isolation of hemogenic endothelial cells and HSPC during their peak generation times in the yolk sac and AGM. We demonstrate methods for dissection of yolk sac and AGM tissues from mouse embryos, and we present optimized tissue digestion and antibody conjugation conditions for maximal cell survival prior to identification and retrieval via FACS. Representative FACS analysis plots are shown that identify the hemogenic endothelial cell and HSPC phenotypes, and describe a methylcellulose-based assay for evaluating their blood forming potential on a clonal level. PMID:27341393

  6. Isolation of Murine Embryonic Hemogenic Endothelial Cells

    PubMed Central

    Marcelo, Kathrina L.; Hirschi, Karen K.

    2016-01-01

    The specification of hemogenic endothelial cells from embryonic vascular endothelium occurs during brief developmental periods within distinct tissues, and is necessary for the emergence of definitive HSPC from the murine extra embryonic yolk sac, placenta, umbilical vessels, and the embryonic aorta-gonad-mesonephros (AGM) region. The transient nature and small size of this cell population renders its reproducible isolation for careful quantification and experimental applications technically difficult. We have established a fluorescence-activated cell sorting (FACS)-based protocol for simultaneous isolation of hemogenic endothelial cells and HSPC during their peak generation times in the yolk sac and AGM. We demonstrate methods for dissection of yolk sac and AGM tissues from mouse embryos, and we present optimized tissue digestion and antibody conjugation conditions for maximal cell survival prior to identification and retrieval via FACS. Representative FACS analysis plots are shown that identify the hemogenic endothelial cell and HSPC phenotypes, and describe a methylcellulose-based assay for evaluating their blood forming potential on a clonal level. PMID:27341393

  7. Angiocrine functions of organ-specific endothelial cells

    PubMed Central

    Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

    2016-01-01

    Preface Endothelial cells lining blood vessel capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establish specialized vascular niches that deploy specific sets of growth factors, known as angiocrine factors, which actively participate in inducing, specifying, patterning, and guiding organ regeneration and maintaining homeostasis and metabolism. Angiocrine factors upregulated in response to injury orchestrates self-renewal and differentiation of tissue-specific repopulating resident stem and progenitor cells into functional organs. Uncovering the precise mechanisms whereby physiological-levels of angiocrine factors are spatially and temporally produced, and distributed by organotypic endothelium to repopulating cells, will lay the foundation for driving organ repair without scarring. PMID:26791722

  8. An association between antibodies specific for endothelial cells and renal transplant failure.

    PubMed

    Perrey, C; Brenchley, P E; Johnson, R W; Martin, S

    1998-06-01

    Human leucocyte antigen (HLA)-specific antibodies, present at the time of transplant, cause renal transplant rejection but cases of rejection of HLA-identical renal transplants indicate that antibodies to non-HLA antigens may also be detrimental. There is increasing evidence that antibodies to antigens present on endothelial cells and monocytes, and on endothelial cells alone, are associated with transplant rejection. We investigated 105 patients with failed renal transplants for the presence of endothelial cell reactive antibodies and compared them with 94 successful transplant patients to determine the role of non-HLA antibodies in transplant failure. Patient sera were tested by enzyme-linked immunoabsorbent assay (ELISA) using as a target fixed cells either from the endothelial/epithelial cell line EAHy.926 or primary cultures of human umbilical vein endothelial cells. Antibody binding was detected using an alkaline phosphatase-conjugated anti-human immunoglobulin G (IgG) antibody. Fourteen of the 105 failed transplant patients had endothelial cell-reactive antibodies as compared with only three of the 94 patients with successful transplants (Fisher's exact test, p = 0.02). Antibody-positive sera were absorbed with the epithelial cell line A549 to remove antibodies directed against the epithelial component of EAHy.926 and with a pool of lymphoblastoid cell line cells to remove HLA-specific antibodies. Absorption did not reduce antibody activity showing the antibodies to be directed against endothelial cell determinants. Antibody-positive sera were also tested by flow cytometry against the monocyte cell line THP-1 and 13 of the 14 patients were negative. In conclusion, we have demonstrated the presence of IgG antibodies directed against endothelial cell determinants in renal transplant recipients in association with renal transplant failure. PMID:9777698

  9. The hyperpolarizing impact of glycine on endothelial cells may be anti-atherogenic.

    PubMed

    McCarty, Mark F; Barroso-Aranda, Jorge; Contreras, Francisco

    2009-08-01

    Studies to date indicate that endothelial cells express glycine-activated chloride channels, which promote hyperpolarization of the endothelial plasma membrane. If such channels are expressed by endothelial cells lining conduit arteries, glycine is likely to have anti-atherogenic activity. This reflects the fact that endothelial hyperpolarization promotes calcium influx, activating the endothelial isoform of nitric oxide synthase, while also down-regulating the activity of the membrane-bound NADPH oxidase, chief endothelial source of superoxide. Since macrophages express glycine-activated chloride channels that suppress production of oxidants and cytokines, glycine may also oppose atherogenesis by influencing intimal macrophage function. In rats, supplemental glycine exerts anti-inflammatory and anti-angiogenic effects attributed to chloride channel activation. Administration of large daily doses of glycine would appear to be practical and safe, and has already been shown to inhibit protein glycation in human diabetics. PMID:19232835

  10. Plastic Compressed Collagen as a Novel Carrier for Expanded Human Corneal Endothelial Cells for Transplantation

    PubMed Central

    Levis, Hannah J.; Peh, Gary S. L.; Toh, Kah-Peng; Poh, Rebekah; Shortt, Alex J.; Drake, Rosemary A. L.; Mehta, Jodhbir S.; Daniels, Julie T.

    2012-01-01

    Current treatments for reversible blindness caused by corneal endothelial cell failure involve replacing the failed endothelium with donor tissue using a one donor-one recipient strategy. Due to the increasing pressure of a worldwide donor cornea shortage there has been considerable interest in developing alternative strategies to treat endothelial disorders using expanded cell replacement therapy. Protocols have been developed which allow successful expansion of endothelial cells in vitro but this approach requires a supporting material that would allow easy transfer of cells to the recipient. We describe the first use of plastic compressed collagen as a highly effective, novel carrier for human corneal endothelial cells. A human corneal endothelial cell line and primary human corneal endothelial cells retained their characteristic cobblestone morphology and expression of tight junction protein ZO-1 and pump protein Na+/K+ ATPase α1 after culture on collagen constructs for up to 14 days. Additionally, ultrastructural analysis suggested a well-integrated endothelial layer with tightly opposed cells and apical microvilli. Plastic compressed collagen is a superior biomaterial in terms of its speed and ease of production and its ability to be manipulated in a clinically relevant manner without breakage. This method provides expanded endothelial cells with a substrate that could be suitable for transplantation allowing one donor cornea to potentially treat multiple patients. PMID:23226443

  11. Expression of an insulin-regulatable glucose carrier in muscle and fat endothelial cells

    NASA Astrophysics Data System (ADS)

    Vilaró, Senen; Palacín, Manuel; Pilch, Paul F.; Testar, Xavier; Zorzano, Antonio

    1989-12-01

    INSULIN rapidly stimulates glucose use in the major target tissues, muscle and fat, by modulating a tissue-specific glucose transporter isoform1-6. Access of glucose to the target tissue is restricted by endothelial cells which line the walls of nonfenestrated capillaries of fat and muscle7. Thus, we examined whether the capillary endothelial cells are actively involved in the modulation of glucose availability by these tissues. We report here the abundant expression of the muscle/fat glucose transporter isoform in endothelial cells, using an immunocytochemical analysis with a monoclonal antibody specific for this isoform1. This expression is restricted to endothelial cells from the major insulin target tissues, and it is not detected in brain and liver where insulin does not activate glucose transport. The expression of the muscle/fat transporter isoform in endothelial cells is significantly greater than in the neighbouring muscle and fat cells. Following administration of insulin to animals in vivo, there occurs a rapid increase in the number of muscle/fat transporters present in the lumenal plasma membrane of the capillary endothelial cells. These results document that insulin promotes the translocation of the muscle/fat glucose transporter in endothelial cells. It is therefore likely that endothelial cells play an important role in the regulation of glucose use by the major insulin target tissues in normal and diseased states.

  12. Endothelial cells and cathepsins: Biochemical and biomechanical regulation.

    PubMed

    Platt, Manu O; Shockey, W Andrew

    2016-03-01

    Cathepsins are mechanosensitive proteases that are regulated not only by biochemical factors, but are also responsive to biomechanical forces in the cardiovascular system that regulate their expression and activity to participate in cardiovascular tissue remodeling. Their elastinolytic and collagenolytic activity have been implicated in atherosclerosis, abdominal aortic aneurysms, and in heart valve disease, all of which are lined by endothelial cells that are the mechanosensitive monolayer of cells that sense and respond to fluid shear stress as the blood flows across the surfaces of the arteries and valve leaflets. Inflammatory cytokine signaling is integrated with biomechanical signaling pathways by the endothelial cells to transcribe, translate, and activate either the cysteine cathepsins to remodel the tissue or to express their inhibitors to maintain healthy cardiovascular tissue structure. Other cardiovascular diseases should now be included in the study of the cysteine cathepsin activation because of the additional biochemical cues they provide that merges with the already existing hemodynamics driving cardiovascular disease. Sickle cell disease causes a chronic inflammation including elevated TNFα and increased numbers of circulating monocytes that alter the biochemical stimulation while the more viscous red blood cells due to the sickling of hemoglobin alters the hemodynamics and is associated with accelerated elastin remodeling causing pediatric strokes. HIV-mediated cardiovascular disease also occurs earlier in than the broader population and the influence of HIV-proteins and antiretrovirals on endothelial cells must be considered to understand these accelerated mechanisms in order to identify new therapeutic targets for prevention. PMID:26458976

  13. Lymphatic endothelial cells support tumor growth in breast cancer

    PubMed Central

    Lee, Esak; Pandey, Niranjan B.; Popel, Aleksander S.

    2014-01-01

    Tumor lymphatic vessels (LV) serve as a conduit of tumor cell dissemination, due to their leaky nature and secretion of tumor-recruiting factors. Though lymphatic endothelial cells (LEC) lining the LV express distinct factors (also called lymphangiocrine factors), these factors and their roles in the tumor microenvironment are not well understood. Here we employ LEC, microvascular endothelial cells (MEC), and human umbilical vein endothelial cells (HUVEC) cultured in triple-negative MDA-MB-231 tumor-conditioned media (TCM) to determine the factors that may be secreted by various EC in the MDA-MB-231 breast tumor. These factors will serve as endothelium derived signaling molecules in the tumor microenvironment. We co-injected these EC with MDA-MB-231 breast cancer cells into animals and showed that LEC support tumor growth, HUVEC have no significant effect on tumor growth, whereas MEC suppress it. Focusing on LEC-mediated tumor growth, we discovered that TCM-treated LEC (‘tumor-educated LEC') secrete high amounts of EGF and PDGF-BB, compared to normal LEC. LEC-secreted EGF promotes tumor cell proliferation. LEC-secreted PDGF-BB induces pericyte infiltration and angiogenesis. These lymphangiocrine factors may support tumor growth in the tumor microenvironment. This study shows that LV serve a novel role in the tumor microenvironment apart from their classical role as conduits of metastasis. PMID:25068296

  14. Androgen receptor in human endothelial cells

    PubMed Central

    Torres-Estay, Verónica; Carreño, Daniela V; San Francisco, Ignacio F; Sotomayor, Paula; Godoy, Alejandro S; Smith, Gary J

    2015-01-01

    Androgen receptor (AR) is a ligand-inducible transcription factor, and a member of the steroid-thyroid-retinoid receptor superfamily, that mediates the biological effects of androgens in a wide range of physiological and pathological processes. AR expression was identified in vascular cells nearly 20 years ago, and recent research has shown that AR mediates a variety of actions of androgens in endothelial and vascular smooth muscle cells. In this mini-review, we review evidence indicating the importance of AR in human endothelial cell (HUVEC) homeostatic and pathogenic processes. Although a role for AR in the modulation of HUVEC biology is evident, the molecular mechanisms by which AR regulates HUVEC homeostasis and disease processes are not fully understood. Understanding these mechanisms could provide critical insights into the processes of pathogenesis of diseases ranging from cardiovascular disease to cancer that are major causes of human morbidity and mortality. PMID:25563353

  15. Endothelial juxtaposition of distinct adult stem cells activates angiogenesis signaling molecules in endothelial cells.

    PubMed

    Mohammadi, Elham; Nassiri, Seyed Mahdi; Rahbarghazi, Reza; Siavashi, Vahid; Araghi, Atefeh

    2015-12-01

    Efficacy of therapeutic angiogenesis needs a comprehensive understanding of endothelial cell (EC) function and biological factors and cells that interplay with ECs. Stem cells are considered the key components of pro- and anti-angiogenic milieu in a wide variety of physiopathological states, and interactions of EC-stem cells have been the subject of controversy in recent years. In this study, the potential effects of three tissue-specific adult stem cells, namely rat marrow-derived mesenchymal stem cells (rBMSCs), rat adipose-derived stem cells (rADSCs) and rat muscle-derived satellite cells (rSCs), on the endothelial activation of key angiogenic signaling molecules, including VEGF, Ang-2, VEGFR-2, Tie-2, and Tie2-pho, were investigated. Human umbilical vein endothelial cells (HUVECs) and rat lung microvascular endothelial cells (RLMECs) were cocultured with the stem cells or incubated with the stem cell-derived conditioned media on Matrigel. Following HUVEC-stem cell coculture, CD31-positive ECs were flow sorted and subjected to western blotting to analyze potential changes in the expression of the pro-angiogenic signaling molecules. Elongation and co-alignment of the stem cells were seen along the EC tubes in the EC-stem cell cocultures on Matrigel, with cell-to-cell dye communication in the EC-rBMSC cocultures. Moreover, rBMSCs and rADSCs significantly improved endothelial tubulogenesis in both juxtacrine and paracrine manners. These two latter stem cells dynamically up-regulated VEGF, Ang-2, VREGR-2, and Tie-2 but down-regulated Tie2-pho and the Tie2-pho/Tie-2 ratio in HUVECs. Induction of pro-angiogenic signaling in ECs by marrow- and adipose-derived MSCs further indicates the significance of stem cell milieu in angiogenesis dynamics. PMID:26068799

  16. Safety of targeting tumor endothelial cell antigens.

    PubMed

    Wagner, Samuel C; Riordan, Neil H; Ichim, Thomas E; Szymanski, Julia; Ma, Hong; Perez, Jesus A; Lopez, Javier; Plata-Munoz, Juan J; Silva, Francisco; Patel, Amit N; Kesari, Santosh

    2016-01-01

    The mechanisms underlying discrimination between "self" and "non-self", a central immunological principle, require careful consideration in immune oncology therapeutics where eliciting anti-cancer immunity must be weighed against the risk of autoimmunity due to the self origin of tumors. Whole cell vaccines are one promising immunotherapeutic avenue whereby a myriad of tumor antigens are introduced in an immunogenic context with the aim of eliciting tumor rejection. Despite the possibility collateral damage to healthy tissues, cancer immunotherapy can be designed such that off target autoimmunity remains limited in scope and severity or completely non-existent. Here we provide an immunological basis for reconciling the safety of cancer vaccines, focusing on tumor endothelial cell vaccines, by discussing the following topics: (a) Antigenic differences between neoplastic and healthy tissues that can be leveraged in cancer vaccine design; (b) The layers of tolerance that control T cell responses directed against antigens expressed in healthy tissues and tumors; and, (c) The hierarchy of antigenic epitope selection and display in response to whole cell vaccines, and how antigen processing and presentation can afford a degree of selectivity against tumors. We conclude with an example of early clinical data utilizing ValloVax™, an immunogenic placental endothelial cell vaccine that is being advanced to target the tumor endothelium of diverse cancers, and we report on the safety and efficacy of ValloVax™ for inducing immunity against tumor endothelial antigens. PMID:27071457

  17. Membrane Cholesterol Modulates LOX-1 Shedding in Endothelial Cells.

    PubMed

    Gioia, Magda; Vindigni, Giulia; Testa, Barbara; Raniolo, Sofia; Fasciglione, Giovanni Francesco; Coletta, Massimiliano; Biocca, Silvia

    2015-01-01

    The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a scavenger receptor responsible for ox-LDL recognition, binding and internalization, which is up-regulated during atherogenesis. Its activation triggers endothelium dysfunction and induces inflammation. A soluble form of LOX-1 has been identified in the human blood and its presence considered a biomarker of cardiovascular diseases. We recently showed that cholesterol-lowering drugs inhibit ox-LDL binding and internalization, rescuing the ox-LDL induced apoptotic phenotype in primary endothelial cells. Here we have investigated the molecular bases of human LOX-1 shedding by metalloproteinases and the role of cell membrane cholesterol on the regulation of this event by modulating its level with MβCD and statins. We report that membrane cholesterol affects the release of different forms of LOX-1 in cells transiently and stably expressing human LOX-1 and in a human endothelial cell line (EA.hy926). In particular, our data show that i) cholesterol depletion triggers the release of LOX-1 in exosomes as a full-length transmembrane isoform and as a truncated ectodomain soluble fragment (sLOX-1); ii) endothelial cells secrete a soluble metalloproteinase which induces LOX-1 ectodomain shedding and iii) long term statins treatment enhances sLOX-1 proteolytic shedding. PMID:26495844

  18. Membrane Cholesterol Modulates LOX-1 Shedding in Endothelial Cells

    PubMed Central

    Testa, Barbara; Raniolo, Sofia; Fasciglione, Giovanni Francesco; Coletta, Massimiliano; Biocca, Silvia

    2015-01-01

    The lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a scavenger receptor responsible for ox-LDL recognition, binding and internalization, which is up-regulated during atherogenesis. Its activation triggers endothelium dysfunction and induces inflammation. A soluble form of LOX-1 has been identified in the human blood and its presence considered a biomarker of cardiovascular diseases. We recently showed that cholesterol-lowering drugs inhibit ox-LDL binding and internalization, rescuing the ox-LDL induced apoptotic phenotype in primary endothelial cells. Here we have investigated the molecular bases of human LOX-1 shedding by metalloproteinases and the role of cell membrane cholesterol on the regulation of this event by modulating its level with MβCD and statins. We report that membrane cholesterol affects the release of different forms of LOX-1 in cells transiently and stably expressing human LOX-1 and in a human endothelial cell line (EA.hy926). In particular, our data show that i) cholesterol depletion triggers the release of LOX-1 in exosomes as a full-length transmembrane isoform and as a truncated ectodomain soluble fragment (sLOX-1); ii) endothelial cells secrete a soluble metalloproteinase which induces LOX-1 ectodomain shedding and iii) long term statins treatment enhances sLOX-1 proteolytic shedding. PMID:26495844

  19. The expression of ADAMTS13 in human microvascular endothelial cells.

    PubMed

    Wang, Anyou; Duan, Qiaohong; Wu, Jingsheng; Liu, Xin; Sun, Zimin

    2016-06-01

    ADAMTS13, as a specific von Willebrand factor (VWF)-cleaving protease, prevents microvascular thrombosis of VWF/platelet thrombi. It has been reported that human vascular endothelial cells could also synthesize and secrete ADAMTS13, and these reports were focused in human umbilical vascular endothelial cells. Considering the particularity of its huge quantity and structure of human microvascular endothelial cells (HMECs) in the body, whether ADAMTS13 is expressed in HMECs also needs to be confirmed. To investigate whether ADAMTS13 is expressed in HMECs. Real-time PCR (RT-PCR) amplification detected ADAMTS13 mRNA in HMEC-1 cell line. The expression and distribution of ADAMTS13 protein and VWF were detected by fluorescence immunoassay and western blot. We observed the expression and distribution of ADAMTS13 in HMECs. We confirmed the expression of ADAMTS13 mRNA in HMEC-1, and found that there were some partly common distributions of ADAMTS13 protein and VWF. This study provides the evidence that HMECs also express ADAMTS13. HMECs might also be a primary source for human plasma ADAMTS13. The overlap region for the distribution of ADAMTS13 and VWF suggests that ADAMTS13 might have a potential regulation role for VWF inside cells. PMID:26366828

  20. Endothelial cell metabolism: parallels and divergences with cancer cell metabolism

    PubMed Central

    2014-01-01

    The stromal vasculature in tumors is a vital conduit of nutrients and oxygen for cancer cells. To date, the vast majority of studies have focused on unraveling the genetic basis of vessel sprouting (also termed angiogenesis). In contrast to the widely studied changes in cancer cell metabolism, insight in the metabolic regulation of angiogenesis is only just emerging. These studies show that metabolic pathways in endothelial cells (ECs) importantly regulate angiogenesis in conjunction with genetic signals. In this review, we will highlight these emerging insights in EC metabolism and discuss them in perspective of cancer cell metabolism. While it is generally assumed that cancer cells have unique metabolic adaptations, not shared by healthy non-transformed cells, we will discuss parallels and highlight differences between endothelial and cancer cell metabolism and consider possible novel therapeutic opportunities arising from targeting both cancer and endothelial cells. PMID:25250177

  1. Molecular analysis of endothelial progenitor cell (EPC) subtypes reveals two distinct cell populations with different identities

    PubMed Central

    2010-01-01

    Background The term endothelial progenitor cells (EPCs) is currently used to refer to cell populations which are quite dissimilar in terms of biological properties. This study provides a detailed molecular fingerprint for two EPC subtypes: early EPCs (eEPCs) and outgrowth endothelial cells (OECs). Methods Human blood-derived eEPCs and OECs were characterised by using genome-wide transcriptional profiling, 2D protein electrophoresis, and electron microscopy. Comparative analysis at the transcript and protein level included monocytes and mature endothelial cells as reference cell types. Results Our data show that eEPCs and OECs have strikingly different gene expression signatures. Many highly expressed transcripts in eEPCs are haematopoietic specific (RUNX1, WAS, LYN) with links to immunity and inflammation (TLRs, CD14, HLAs), whereas many transcripts involved in vascular development and angiogenesis-related signalling pathways (Tie2, eNOS, Ephrins) are highly expressed in OECs. Comparative analysis with monocytes and mature endothelial cells clusters eEPCs with monocytes, while OECs segment with endothelial cells. Similarly, proteomic analysis revealed that 90% of spots identified by 2-D gel analysis are common between OECs and endothelial cells while eEPCs share 77% with monocytes. In line with the expression pattern of caveolins and cadherins identified by microarray analysis, ultrastructural evaluation highlighted the presence of caveolae and adherens junctions only in OECs. Conclusions This study provides evidence that eEPCs are haematopoietic cells with a molecular phenotype linked to monocytes; whereas OECs exhibit commitment to the endothelial lineage. These findings indicate that OECs might be an attractive cell candidate for inducing therapeutic angiogenesis, while eEPC should be used with caution because of their monocytic nature. PMID:20465783

  2. Junctional communication is induced in migrating capillary endothelial cells.

    PubMed

    Pepper, M S; Spray, D C; Chanson, M; Montesano, R; Orci, L; Meda, P

    1989-12-01

    Using an in vitro model in which a confluent monolayer of capillary endothelial cells is mechanically wounded, gap junction-mediated intercellular communication has been studied by loading the cells with the fluorescent dye, Lucifer Yellow. Approximately 40-50% of the cells in a nonwounded confluent monolayer were coupled in groups of four to five cells (basal level). Basal levels of communication were also observed in sparse and preconfluent cultures, but were reduced in postconfluent monolayers. 30 min after wounding, coupling was markedly reduced between cells lining the wound. Communication at the wound was partially reestablished by 2 h, exceeded basal levels after 6 h and reached a maximum after 24 h, at which stage approximately 90% of the cells were coupled in groups of six to seven cells. When the wound had closed (after 8 d), the increase in communication was no longer observed. Induction of wound-associated communication was unaffected by exposure of the cells to the DNA synthesis inhibitor mitomycin C, but was prevented by the protein synthesis inhibitor, cycloheximide. The induction of wound-associated communication was also inhibited when migration was prevented by placing the cells immediately after wounding at 22 degrees C or after exposure to cytochalasin D, suggesting that the increase in communication is dependent on cells migrating into the wound area. In contrast, migration was not prevented when coupling was blocked by exposure of the cells to retinoic acid, although this agent did disrupt the characteristic sheet-like pattern of migration typically seen during endothelial repair. These results suggest that junctional communication may play an important role in wound repair, possibly by coordinating capillary endothelial cell migration. PMID:2592412

  3. Angiocrine functions of organ-specific endothelial cells.

    PubMed

    Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

    2016-01-21

    Endothelial cells that line capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establishes specialized vascular niches that deploy sets of growth factors, known as angiocrine factors. These cues participate actively in the induction, specification, patterning and guidance of organ regeneration, as well as in the maintainance of homeostasis and metabolism. When upregulated following injury, they orchestrate self-renewal and differentiation of tissue-specific resident stem and progenitor cells into functional organs. Uncovering the mechanisms by which organotypic endothelium distributes physiological levels of angiocrine factors both spatially and temporally will lay the foundation for clinical trials that promote organ repair without scarring. PMID:26791722

  4. Control of proliferation of human vascular endothelial cells. Characterization of the response of human umbilical vein endothelial cells to fibroblast growth factor, epidermal growth factor, and thrombin.

    PubMed

    Gospodarowicz, D; Brown, K D; Birdwell, C R; Zetter, B R

    1978-06-01

    Because the response of human endothelial cells to growth factors and conditioning agents has broad implications for our understanding of wound healing angiogenesis, and human atherogenesis, we have investigated the responses of these cells to the fibroblast (FGF) and epidermal growth factors (EGF), as well as to the protease thrombin, which has been previously shown to potentiate the growth response of other cell types of FGF and EGF. Because the vascular endothelial cells that form the inner lining of blood vessels may be expected to be exposed to high thrombin concentrations after trauma or in pathological states associated with thrombosis, they are of particular interest with respect to the physiological role of this protease in potentiating cell proliferation. Our results indicate that human vascular endothelial cells respond poorly to either FGF or thrombin alone. In contrast, when cells are maintained in the presence of thrombin, their proliferative response to FGF is greatly increased even in cultures seeded at a density as low as 3 cells/mm2. Human vascular endothelial cells also respond to EGF and thrombin, although their rate of proliferation is much slower than when maintained with FGF and thrombin. In contrast, bovine vascular endothelial cells derived from vascular territories as diverse as the bovine heart, aortic arch, and umbilical vein respond maximally to FGF alone and neither respond to nor bind EGF. Furthermore, the response of bovine vascular endothelial cells to FGF was not potentiated by thrombin, indicating that the set of factors controlling the proliferation of vascular endothelial cells could be species-dependent. The requirement of cultured human vascular endothelial cells for thrombin could explain why the human cells, in contrast to bovine endothelial cells, are so difficult to maintain in tissue culture. Our results demonstrate that by using FGF and thrombin one can develop cultures of human vascular endothelial cells capable of

  5. Bilirubin is an Endogenous Antioxidant in Human Vascular Endothelial Cells.

    PubMed

    Ziberna, Lovro; Martelanc, Mitja; Franko, Mladen; Passamonti, Sabina

    2016-01-01

    Bilirubin is a standard serum biomarker of liver function. Inexplicably, it is inversely correlated with cardiovascular disease risk. Given the role of endothelial dysfunction in originating cardiovascular diseases, direct analysis of bilirubin in the vascular endothelium would shed light on these relationships. Hence, we used high-performance liquid chromatography coupled with thermal lens spectrometric detection and diode array detection for the determination of endogenous cellular IXα-bilirubin. To confirm the isomer IXα-bilirubin, we used ultra-performance liquid chromatography coupled with a high-resolution mass spectrometer using an electrospray ionization source, as well as tandem mass spectrometric detection. We measured bilirubin in both arterial and venous rat endothelium (0.9-1.5 pmol mg(-1) protein). In the human endothelial Ea.hy926 cell line, we demonstrated that intracellular bilirubin (3-5 pmol mg(-1) protein) could be modulated by either extracellular bilirubin uptake, or by up-regulation of heme oxygenase-1, a cellular enzyme related to endogenous bilirubin synthesis. Moreover, we determined intracellular antioxidant activity by bilirubin, with EC50 = 11.4 ± 0.2 nM, in the range of reported values of free serum bilirubin (8.5-13.1 nM). Biliverdin showed similar antioxidant properties as bilirubin. We infer from these observations that intra-endothelial bilirubin oscillates, and may thus be a dynamic factor of the endothelial function. PMID:27381978

  6. Bilirubin is an Endogenous Antioxidant in Human Vascular Endothelial Cells

    PubMed Central

    Ziberna, Lovro; Martelanc, Mitja; Franko, Mladen; Passamonti, Sabina

    2016-01-01

    Bilirubin is a standard serum biomarker of liver function. Inexplicably, it is inversely correlated with cardiovascular disease risk. Given the role of endothelial dysfunction in originating cardiovascular diseases, direct analysis of bilirubin in the vascular endothelium would shed light on these relationships. Hence, we used high-performance liquid chromatography coupled with thermal lens spectrometric detection and diode array detection for the determination of endogenous cellular IXα-bilirubin. To confirm the isomer IXα-bilirubin, we used ultra-performance liquid chromatography coupled with a high-resolution mass spectrometer using an electrospray ionization source, as well as tandem mass spectrometric detection. We measured bilirubin in both arterial and venous rat endothelium (0.9–1.5 pmol mg−1 protein). In the human endothelial Ea.hy926 cell line, we demonstrated that intracellular bilirubin (3–5 pmol mg−1 protein) could be modulated by either extracellular bilirubin uptake, or by up-regulation of heme oxygenase-1, a cellular enzyme related to endogenous bilirubin synthesis. Moreover, we determined intracellular antioxidant activity by bilirubin, with EC50 = 11.4 ± 0.2 nM, in the range of reported values of free serum bilirubin (8.5–13.1 nM). Biliverdin showed similar antioxidant properties as bilirubin. We infer from these observations that intra-endothelial bilirubin oscillates, and may thus be a dynamic factor of the endothelial function. PMID:27381978

  7. Different forms of human vascular adhesion protein-1 (VAP-1) in blood vessels in vivo and in cultured endothelial cells: implications for lymphocyte-endothelial cell adhesion models.

    PubMed

    Salmi, M; Jalkanen, S

    1995-10-01

    Vascular endothelium plays a pivotal role in controlling leukocyte extravasation from the blood into the tissues. Vascular adhesion protein-1 (VAP-1) is a novel endothelial cell molecule which mediates lymphocyte binding to the vascular lining (Salmi, M., and Jalkanen, S., Science 1992. 257:1407). In this study, we analyzed endothelial cell type-specific differences of VAP-1. In vivo, VAP-1 is a 90/170-kDa molecule which is mainly expressed on the lumenal surface and in cytoplasmic granules of peripheral lymph node-type postcapillary venules (high endothelial venules, HEV). In tonsil HEV, VAP-1 is modified with abundant sialic acids. VAP-1 is also detectable in the cytoplasm of human umbilical vein endothelial cells (HUVEC) and in an endothelial cell hybrid EaHy-926, although both cell types lack detectable surface VAP-1. Cultured endothelial cells do not express MECA-79-defined peripheral lymph node addressins either. VAP-1 was not translocated onto the endothelial cell surface after stimulation with multiple cytokines, mitogens or secretagogues which induced expression of other known endothelial adhesion molecules. Biochemical analyses revealed that VAP-1 is a approximately 180-kDa protein in these endothelial cell types. Digestions with neuraminidase, O-glycanase and N-glycanase, as well as treatment of cells with tunicamycin and benzyl-N-acetylgalactosaminide, did not alter the molecular mass of VAP-1 in EaHy-926. Pulse-chase experiments showed that VAP-1 is directly synthesized as a 180-kDa molecule without any detectable precursors. Thus, in cultured endothelial cells, VAP-1 is a 180-kDa protein which is devoid of post-translational modifications, and in particular, lacks the sialic acids crucial for the function of VAP-1 in tonsil vessels. Notably, the endothelial cell types commonly used as a model in studying lymphocyte-endothelial cell interactions lack surface expression of VAP-1 and peripheral node addressins, and hence are inherently of limited use in

  8. Biomechanics and Intracellular Dynamics of Vascular Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Ou-Yang, H. Daniel

    2004-03-01

    Understanding the internal mechanical properties of living cells is essential to gain insight to basic cellular functions ranging from cellular signal transduction, intracellular traffics to cell motility. Vascular endothelial cells form a single cell layer that lines all blood vessels and serves to regulate exchanges between the blood stream and the surrounding tissues. Endothelial cells are one of the most studied cell types because of their roles in cardiovascular diseases and the linkage between their growth control and strategies of cancer treatments. This talk reports the application of a novel methodology by which scientists can explore cellular functions and study cytoskeleton dynamics of living cells at the subcellular level with minimal invasion. The methodology is based on the realization that optical tweezers can be used to measure the mechanical properties of the cytoskeleton in the vicinity of organelles and cellular structures. Optical tweezers is a technique based on the physics that dielectric materials, such as silica beads, latex particles or protein aggregates are attracted to and thus trapped at the focal point of a tightly focused laser beam in an aqueous medium. It has been shown that viscoelasticity can be determined from the movements of the trapped object in an oscillating optical tweezers. Applying the oscillating tweezers to intracellular cellular structures, we were able to determine the frequency dependent mechanical properties of the interior of cultured bovine endothelial cells. In contrast to the viscoelastic behavior expected of a network of cytoskelatal proteins, we found unusually large fluctuations in both elastic and loss moduli of the cell interior. More surprisingly, both mechanical moduli showed rhythmic behavior with a periodicity in the range of 20 - 30 seconds in healthy living cells. The rhythm could be altered by drug treatments, and the amplitude of the fluctuations diminished when cells were depleted of nutrients

  9. Imbalance of mitochondrial-nuclear cross talk in isocyanate mediated pulmonary endothelial cell dysfunction☆

    PubMed Central

    Panwar, Hariom; Jain, Deepika; Khan, Saba; Pathak, Neelam; Raghuram, Gorantla V.; Bhargava, Arpit; Banerjee, Smita; Mishra, Pradyumna K.

    2013-01-01

    Mechanistic investigations coupled with epidemiology, case-control, cohort and observational studies have increasingly linked isocyanate exposure (both chronic and acute) with pulmonary morbidity and mortality. Though ascribed for impairment in endothelial cell function, molecular mechanisms of these significant adverse pulmonary outcomes remains poorly understood. As preliminary studies conducted in past have failed to demonstrate a cause-effect relationship between isocyanate toxicity and compromised pulmonary endothelial cell function, we hypothesized that direct exposure to isocyanate may disrupt endothelial structural lining, resulting in cellular damage. Based on this premise, we comprehensively evaluated the molecular repercussions of methyl isocyanate (MIC) exposure on human pulmonary arterial endothelial cells (HPAE-26). We examined MIC-induced mitochondrial oxidative stress, pro-inflammatory cytokine response, oxidative DNA damage response and apoptotic index. Our results demonstrate that exposure to MIC, augment mitochondrial reactive oxygen species production, depletion in antioxidant defense enzymes, elevated pro-inflammatory cytokine response and induced endothelial cell apoptosis via affecting the balance of mitochondrial-nuclear cross talk. We herein delineate the first and direct molecular cascade of isocyanate-induced pulmonary endothelial cell dysfunction. The results of our study might portray a connective link between associated respiratory morbidities with isocyanate exposure, and indeed facilitate to discern the exposure-phenotype relationship in observed deficits of pulmonary endothelial cell function. Further, understanding of inter- and intra-cellular signaling pathways involved in isocyanate-induced endothelial damage would not only aid in biomarker identification but also provide potential new avenues to target specific therapeutic interventions. PMID:24024149

  10. Endothelial cell permeability to water and antipyrine

    SciTech Connect

    Garrick, R.A.

    1986-03-05

    The endothelium provides a structural barrier between plasma constituents and the tissues. The permeability characteristics of the the endothelial cells regulate the transcellular movement of materials across this barrier while other movement is paracellular. In this study the permeability of the endothelial cells to tritiated water (/sup 3/HHO) and /sup 14/C-labeled antipyrine (AP) was investigated. The cells were isolated non-enzymatically from calf pulmonary artery and were maintained in culture and used between the seventh and fifteenth passage. The cells were removed from the T-flasks with a rubber policeman, titurated with a 22g needle and centrifuged. The cells were mixed with an extracellular marker, drawn into polyethylene tubing and packed by centrifugation for use in the linear diffusion technique. All measurements were made at 37 C. The diffusion coefficients for /sup 3/HHO through the packed cells (D), the intracellular material (D/sub 2/), and the extracellular material (D/sub 1/) were 0.682, 0.932 and 2.45 x 10/sup -5/ cm/sup 2/ s/sup -1/ and for AP were 0.273, 0.355 and 1.13 x 10/sup -5/ cm/sup 2/ s/sup -1/ respectively. The permeability coefficient calculated by the series-parallel pathway model for /sup 3/HHO was higher than that for AP and for both /sup 3/HHO and AP were lower than those calculated for isolated lung cells and erythrocytes.

  11. Dysfunctional endothelial cells directly stimulate cancer inflammation and metastasis

    PubMed Central

    Franses, Joseph W.; Drosu, Natalia C.; Gibson, William J.; Chitalia, Vipul C.; Edelman, Elazer R.

    2013-01-01

    Although the influence of context-dependent endothelial cell regulation of vascular disease and repair is well-established, the privileged roles endothelial cells play as paracrine regulators of tumor progression has only recently become appreciated. We hypothesized that if the same endothelial physiology governs vascular and cancer biology then endothelial cell control in cancer should follow endothelial regulation of vascular health. Healthy endothelial cells promote vascular repair and inhibit tumor invasiveness and metastasis; dysfunctional endothelial cells have the opposite effects. We now ask if dysfunctionally activated endothelial cells will promote cancer cell inflammatory signaling and aggressive properties. Indeed, while factors released from quiescent ECs induce balanced inflammatory signaling, correlating with decreased proliferation and invasiveness, factors released from dysfunctional ECs robustly activated NF-κB and STAT3 signaling within cancer cells, correlating with increased in vitro invasiveness and decreased proliferation and survival. Furthermore, matrix-embedded dysfunctional endothelial cells stimulated intratumoral pro-inflammatory signaling and spontaneous metastasis, while simultaneously slowing net primary tumor growth, when implanted adjacent to Lewis lung carcinoma tumors. These studies may broaden our realization of the roles of endothelial function and dysfunction, increase understanding and control of the tumor microenvironment, and facilitate optimization of anti-angiogenic and vascular-modifying therapies in cancer and related diseases. PMID:23463345

  12. KRIT1 Protein Depletion Modifies Endothelial Cell Behavior via Increased Vascular Endothelial Growth Factor (VEGF) Signaling*

    PubMed Central

    DiStefano, Peter V.; Kuebel, Julia M.; Sarelius, Ingrid H.; Glading, Angela J.

    2014-01-01

    Disruption of endothelial cell-cell contact is a key event in many cardiovascular diseases and a characteristic of pathologically activated vascular endothelium. The CCM (cerebral cavernous malformation) family of proteins (KRIT1 (Krev-interaction trapped 1), PDCD10, and CCM2) are critical regulators of endothelial cell-cell contact and vascular homeostasis. Here we show novel regulation of vascular endothelial growth factor (VEGF) signaling in KRIT1-depleted endothelial cells. Loss of KRIT1 and PDCD10, but not CCM2, increases nuclear β-catenin signaling and up-regulates VEGF-A protein expression. In KRIT1-depleted cells, increased VEGF-A levels led to increased VEGF receptor 2 (VEGFR2) activation and subsequent alteration of cytoskeletal organization, migration, and barrier function and to in vivo endothelial permeability in KRIT1-deficient animals. VEGFR2 activation also increases β-catenin phosphorylation but is only partially responsible for KRIT1 depletion-dependent disruption of cell-cell contacts. Thus, VEGF signaling contributes to modifying endothelial function in KRIT1-deficient cells and microvessel permeability in Krit1+/− mice; however, VEGF signaling is likely not the only contributor to disrupted endothelial cell-cell contacts in the absence of KRIT1. PMID:25320085

  13. Sulforaphane Decreases Endothelial Cell Apoptosis in Fuchs Endothelial Corneal Dystrophy: A Novel Treatment

    PubMed Central

    Ziaei, Alireza; Schmedt, Thore; Chen, Yuming; Jurkunas, Ula V.

    2013-01-01

    Purpose. Fuchs endothelial corneal dystrophy (FECD) is an oxidative stress disorder that leads to age-related and gradual loss of corneal endothelial cells resulting in corneal edema and loss of vision. To date, other than surgical intervention, there are no treatment options for patients with FECD. We have shown that in FECD, there is a deficiency in nuclear factor erythroid 2-related factor 2 (Nrf2)–regulated antioxidant defense due to decreased Nrf2 nuclear translocation and activation of antioxidant response element (ARE). In this study, we used sulforaphane (SFN) and D3T to investigate a strategy of targeting Nrf2-ARE in FECD. Methods. FECD and normal ex vivo corneas and human corneal endothelial cell lines were pretreated with SFN or D3T and exposed to oxidative stress with tert-Butyl hydroperoxide (tBHP). Apoptosis was detected with TUNEL. Cellular localization of Nrf2 and p53 was assessed by immunohistochemistry. Effect of SFN was determined by using DCFDA assay, Western blot and real-time PCR. Results. After pretreatment with SFN, oxidative stress was induced with tBHP. In ex vivo FECD specimens, SFN decreased CEC apoptosis by 55% in unstressed group and by 43% in tBHP-treated specimens. SFN enhanced nuclear translocation of Nrf2 in FECD specimens and decreased p53 staining under oxidative stress. Pretreatment with SFN enhanced cell viability by decreasing intracellular reactive oxygen species production. Upregulation of Nrf2 levels led to increased synthesis of DJ-1, heme oxygenase 1, and nicotinamide adenine dinucleotide quinone oxidoreductase-1. SFN significantly upregulated major ARE-dependent antioxidants and ameliorated oxidative stress–induced apoptosis in FECD. Conclusions. Our results suggest that targeting Nrf2-ARE pathway may arrest degenerative cell loss seen in FECD. PMID:24030461

  14. Endothelial cell metabolism in normal and diseased vasculature

    PubMed Central

    Eelen, Guy; de Zeeuw, Pauline; Simons, Michael; Carmeliet, Peter

    2015-01-01

    Higher organisms rely on a closed cardiovascular circulatory system with blood vessels supplying vital nutrients and oxygen to distant tissues. Not surprisingly, vascular pathologies rank among the most life-threatening diseases. At the crux of most of these vascular pathologies are (dysfunctional) endothelial cells (ECs), the cells lining the blood vessel lumen. ECs display the remarkable capability to switch rapidly from a quiescent state to a highly migratory and proliferative state during vessel sprouting. This angiogenic switch has long been considered to be dictated by angiogenic growth factors (eg vascular endothelial growth factor; VEGF) and other signals (eg Notch) alone, but recent findings show that it is also driven by a metabolic switch in ECs. Furthermore, these changes in metabolism may even override signals inducing vessel sprouting. Here, we review how EC metabolism differs between the normal and dysfunctional/diseased vasculature and how it relates to or impacts the metabolism of other cell types contributing to the pathology. We focus on the biology of ECs in tumor blood vessel and diabetic ECs in atherosclerosis as examples of the role of endothelial metabolism in key pathological processes. Finally, current as well as unexplored ‘EC metabolism’-centric therapeutic avenues are discussed. PMID:25814684

  15. Endothelial cell metabolism in normal and diseased vasculature.

    PubMed

    Eelen, Guy; de Zeeuw, Pauline; Simons, Michael; Carmeliet, Peter

    2015-03-27

    Higher organisms rely on a closed cardiovascular circulatory system with blood vessels supplying vital nutrients and oxygen to distant tissues. Not surprisingly, vascular pathologies rank among the most life-threatening diseases. At the crux of most of these vascular pathologies are (dysfunctional) endothelial cells (ECs), the cells lining the blood vessel lumen. ECs display the remarkable capability to switch rapidly from a quiescent state to a highly migratory and proliferative state during vessel sprouting. This angiogenic switch has long been considered to be dictated by angiogenic growth factors (eg, vascular endothelial growth factor) and other signals (eg, Notch) alone, but recent findings show that it is also driven by a metabolic switch in ECs. Furthermore, these changes in metabolism may even override signals inducing vessel sprouting. Here, we review how EC metabolism differs between the normal and dysfunctional/diseased vasculature and how it relates to or affects the metabolism of other cell types contributing to the pathology. We focus on the biology of ECs in tumor blood vessel and diabetic ECs in atherosclerosis as examples of the role of endothelial metabolism in key pathological processes. Finally, current as well as unexplored EC metabolism-centric therapeutic avenues are discussed. PMID:25814684

  16. Heparin Binds Endothelial Cell Growth Factor, the Principal Endothelial Cell Mitogen in Bovine Brain

    NASA Astrophysics Data System (ADS)

    Maciag, Thomas; Mehlman, Tevie; Friesel, Robert; Schreiber, Alain B.

    1984-08-01

    Endothelial cell growth factor (ECGF), an anionic polypeptide mitogen, binds to immobilized heparin. The interaction between the acidic polypeptide and the anionic carbohydrate suggests a mechanism that is independent of ion exchange. Monoclonal antibodies to purified bovine ECGF inhibited the biological activity of ECGF in crude preparations of bovine brain. These data indicate that ECGF is the principal mitogen for endothelial cells from bovine brain, that heparin affinity chromatography may be used to purify and concentrate ECGF, and that the affinity of ECGF for heparin may have structural and perhaps biological significance.

  17. A quantitative analysis of the reduction in oxygen levels required to induce up-regulation of vascular endothelial growth factor (VEGF) mRNA in cervical cancer cell lines

    PubMed Central

    Chiarotto, J A; Hill, R P

    1999-01-01

    The presence of hypoxia (low oxygen concentrations) in solid tumours correlates with poor prognosis, increased metastasis, and resistance to radiotherapy and some forms of chemotherapy. Malignant cells produce an angiogenesis factor, vascular endothelial growth factor (VEGF), which may increase metastatic ability and is up-regulated in the presence of hypoxia. Clinical data for cancers of the cervix and head and neck relate oxygen levels in the tumour to treatment outcome. This suggests the possibility that the presence of VEGF mRNA might be used as a marker for relevant levels of hypoxia. Suspension cultures of three human cervical cancer cell lines, SiHa, ME-180 and HeLa, were used to investigate up-regulation of VEGF mRNA levels following exposure to precisely defined oxygen concentrations for 2 or 4 h. An oxygen sensor was used to confirm the actual levels of dissolved oxygen present. The oxygen concentrations which caused half-maximal upregulation (the Km value) of VEGF mRNA level in the three cell lines were similar except for one instance (Km at 4 h: SiHa 27.0 ± 5.7 μM, ME-180 16.8 ± 3.3 μM, HeLa 13.0 ± 1.8 μM, SiHa and HeLa P = 0.01). The Km values for the HeLa cell line as measured at 2 h (24.9 ± 0.8 μM) and 4 h (13.0 ± 1.8 μM) were significantly different (P < 0.0001). VEGF mRNA half-lives measured in air were consistent with values in the literature (SiHa 59.8 ± 5.8 min, ME-180 44.4 ± 7.2 min, HeLa 44.5 ± 6.3 min). Differences in oxygen consumption at low oxygen concentrations were noted between the different cell lines. Stirring in suspension culture was found to induce VEGF mRNA in SiHa cells. The presence of VEGF mRNA may be a marker for radiobiologic hypoxia. © 1999 Cancer Research Campaign PMID:10408392

  18. Synthesis of an endothelial cell mimicking surface containing thrombomodulin and endothelial protein C receptor

    NASA Astrophysics Data System (ADS)

    Kador, Karl Erich

    Synthetic materials for use in blood contacting applications have been studied for many years with limited success. One of the main areas of need for these materials is the design of synthetic vascular grafts for use in the hundreds of thousands of patients who have coronary artery bypass grafting, many without suitable veins for autologous grafts. The design of these grafts is constrained by two common modes of failure, the formation of intimal hyperplasia (IH) and thrombosis. IH formation has been previously linked to a mismatching of the mechanical properties of the graft and has been overcome by creating grafts using materials whose compliance mimics that of the native artery. Several techniques and surface modification have been designed to limit thrombosis on the surface of synthetic materials. One which has shown the greatest promise is the immobilization of Thrombomodulin (TM), a protein found on the endothelial cell membrane lining native blood vessels involved in the activation of the anticoagulant Protein C (PC). While TM immobilization has been shown to arrest thrombin formation and limit fibrous formations in in-vitro and in-vivo experiments, it has shown to be transport limiting under arterial flow. On the endothelial cell surface, TM is co-localized with Endothelial Protein C Receptor (EPCR), which increases PC transport onto the cell surface and increases PC activation via TM between 20-100 fold. This dissertation will describe the chemical modification of medical grade polyurethane (PU), whose compliance has been shown to match that of native arteries. This modification will enable the immobilization of two proteins on an enzymatically relevant scale estimated at less than 10 nm. This dissertation will further describe the immobilization of the proteins TM and EPCR, and analyze the ability of a surface co-immobilized with these proteins to activate the anticoagulant PC. Finally, it will compare the ability of this co-immobilized surface to delay

  19. Endothelial Cell Dynamics during Anastomosis in vitro

    PubMed Central

    Diaz-Santana, Anthony; Shan, Mengrou; Stroock, Abraham D.

    2015-01-01

    Vascular anastomosis –the fusion of vessels from two distinct branches of the vascular system – represents a critical step in vascular growth under both healthy and pathological conditions, in vivo, and presents an important target for engineering of vascularized tissues, in vitro. Recent works in animal models have advanced our understanding of the molecular and cellular players in vascular anastomosis, but questions remain related to cellular dynamics and control of this process, in vitro. In this study, we exploited a three-dimensional (3-D) culture platform to examine the dynamics of endothelial cell (EC) during and after vascular anastomosis by allowing angiogenesis and vasculogenesis to proceed in parallel. We show that anastomosis occurs between sprouts formed by angiogenesis from an endothelium and tubes formed by vasculogenesis in the bulk of a 3-D matrix. This fusion leads to highly connected vessels that span from the surface of the matrix into the bulk in a manner that depends on cell density and identity. Further, we observe and analyze intermixing of endothelial cells of distinct origin (surface versus bulk) within the vessels structures that are formed; we provide evidence that the cells migrate along pre-existing vessels segments as part of this intermixing process. We conclude that anastomosis can occur between vessels emerging by angiogenesis and vasculogenesis and that this process may play an important role in contexts such as wound healing. PMID:25790315

  20. The relationship between oxidised LDL, endothelial progenitor cells and coronary endothelial function in patients with CHD

    PubMed Central

    Watt, Jonathan; Kennedy, Simon; Ahmed, Nadeem; Hayhurst, James; McClure, John D; Berry, Colin; Wadsworth, Roger M; Oldroyd, Keith G

    2016-01-01

    Objective The balance between coronary endothelial dysfunction and repair is influenced by many protective and deleterious factors circulating in the blood. We studied the relationship between oxidised low-density lipoprotein (oxLDL), circulating endothelial progenitor cells (EPCs) and coronary endothelial function in patients with stable coronary heart disease (CHD). Methods 33 patients with stable CHD were studied. Plasma oxLDL was measured using ELISA, coronary endothelial function was assessed using intracoronary acetylcholine infusion and EPCs were quantified using flow cytometry for CD34+/KDR+ cells. Results Plasma oxLDL correlated positively with the number of EPCs in the blood (r=0.46, p=0.02). There was a positive correlation between the number of circulating EPCs and coronary endothelial function (r=0.42, p=0.04). There was no significant correlation between oxLDL and coronary endothelial function. Conclusions Plasma levels of oxLDL are associated with increased circulating EPCs in the blood of patients with CHD, which may reflect a host-repair response to endothelial injury. Patients with stable CHD had a high prevalence of coronary endothelial dysfunction, which was associated with lower numbers of circulating EPCs, suggesting a mechanistic link between endothelial dysfunction and the pathogenesis of atherosclerosis. PMID:26848395

  1. Endothelial Cell Toxicity of Vancomycin Infusion Combined with Other Antibiotics

    PubMed Central

    Drouet, Maryline; Chai, Feng; Barthélémy, Christine; Lebuffe, Gilles; Debaene, Bertrand; Odou, Pascal

    2015-01-01

    French guidelines recommend central intravenous (i.v.) infusion for high concentrations of vancomycin, but peripheral intravenous (p.i.v.) infusion is often preferred in intensive care units. Vancomycin infusion has been implicated in cases of phlebitis, with endothelial toxicity depending on the drug concentration and the duration of the infusion. Vancomycin is frequently infused in combination with other i.v. antibiotics through the same administrative Y site, but the local toxicity of such combinations has been poorly evaluated. Such an assessment could improve vancomycin infusion procedures in hospitals. Human umbilical vein endothelial cells (HUVEC) were challenged with clinical doses of vancomycin over 24 h with or without other i.v. antibiotics. Cell death was measured with the alamarBlue test. We observed an excess cellular death rate without any synergistic effect but dependent on the numbers of combined infusions when vancomycin and erythromycin or gentamicin were infused through the same Y site. Incompatibility between vancomycin and piperacillin-tazobactam was not observed in our study, and rinsing the cells between the two antibiotic infusions did not reduce endothelial toxicity. No endothelial toxicity of imipenem-cilastatin was observed when combined with vancomycin. p.i.v. vancomycin infusion in combination with other medications requires new recommendations to prevent phlebitis, including limiting coinfusion on the same line, reducing the infusion rate, and choosing an intermittent infusion method. Further studies need to be carried out to explore other drug combinations in long-term vancomycin p.i.v. therapy so as to gain insight into the mechanisms of drug incompatibility under multidrug infusion conditions. PMID:26055373

  2. Liver Sinusoidal Endothelial Cells Escape Senescence by Loss of p19ARF

    PubMed Central

    Koudelkova, Petra; Weber, Gerhard; Mikulits, Wolfgang

    2015-01-01

    Liver sinusoidal endothelial cells (LSECs) represent a highly differentiated cell type that lines hepatic sinusoids. LSECs form a discontinuous endothelium due to fenestrations under physiological conditions, which are reduced upon chronic liver injury. Cultivation of rodent LSECs associates with a rapid onset of stress-induced senescence a few days post isolation, which limits genetic and biochemical studies ex vivo. Here we show the establishment of LSECs isolated from p19ARF-/- mice which undergo more than 50 cell doublings in the absence of senescence. Isolated p19ARF-/- LSECs display a cobblestone-like morphology and show the ability of tube formation. Analysis of DNA content revealed a stable diploid phenotype after long-term passaging without a gain of aneuploidy. Notably, p19ARF-/- LSECs express the endothelial markers CD31, vascular endothelial growth factor receptor (VEGFR)-2, VE-cadherin, von Willebrand factor, stabilin-2 and CD146 suggesting that these cells harbor and maintain an endothelial phenotype. In line, treatment with small molecule inhibitors against VEGFR-2 caused cell death, demonstrating the sustained ability of p19ARF-/- LSECs to respond to anti-angiogenic therapeutics. From these data we conclude that loss of p19ARF overcomes senescence of LSECs, allowing immortalization of cells without losing endothelial characteristics. Thus, p19ARF-/- LSECs provide a novel cellular model to study endothelial cell biology. PMID:26528722

  3. Lonidamine Causes Inhibition of Angiogenesis-Related Endothelial Cell Functions1

    PubMed Central

    Del Bufalo, Donatella; Trisciuoglio, Daniela; Scarsella, Marco; D'Amati, Giulia; Candiloro, Antonio; Iervolino, Angela; Leonetti, Carlo; Zupi, Gabriella

    2004-01-01

    Abstract The aim of this study was to assess whether lonidamine (LND) interferes with some steps in angiogenesis progression. We report here, for the first time, that LND inhibited angiogenic-related endothelial cell functions in a dose-dependent manner (1–50 µg/ml). In particular, LND decreased proliferation, migration, invasion, and morphogenesis on matrigel of different endothelial cell lines. Zymographic and Western blot analysis assays showed that LND treatment produced a reduction in the secretion of matrix metalloproteinase- 2 and metalloproteinase-9 by endothelial cells. Vessel formation in a matrigel plug was also reduced by LND. The viability, migration, invasion, and matrix metalloproteinase production of different tumor cell lines were not affected by low doses of LND (1–10 µg/ml), whereas 50 µg/ml LND, which corresponds to the dose used in clinical management of tumors, triggered apoptosis both in endothelial and tumor cells. Together, these data demonstrate that LND is a compound that interferes with endothelial cell functions, both at low and high doses. Thus, the effect of LND on endothelial cell functions, previously undescribed, may be a significant contributor to the antitumor effect of LND observed for clinical management of solid tumors. PMID:15548359

  4. Endothelial monolayers on collagen-coated nanofibrous membranes: cell-cell and cell-ECM interactions.

    PubMed

    Kang, Donggu; Kim, Jeong Hwa; Jeong, Young Hun; Kwak, Jong-Young; Yoon, Sik; Jin, Songwan

    2016-06-01

    Endothelial cells (ECs) form a monolayer lining over the entire vascular wall and play an important role in maintaining vascular homeostasis and cancer metastasis. Loss of proper endothelial function can lead to vascular diseases. Therefore, the endothelial monolayer is particularly important in tissue regeneration and mimicking vascular tissue in vitro. Numerous studies have described the effects of ECs on nanofibers made from a variety of synthetic polymer materials designed to mimic the extracellular matrix (ECM). However, little is known about maintaining the integrity of ECs in in vitro systems. Here we describe polycaprolactone nanofibrous membranes coated with collagen gel that overcome many limitations of conventional nanofibers used for engineering endothelia. We investigated cell-cell and cell-ECM junctional complexes using collagen-coated and conventional nanofibrous membranes. Conventional nanofibrous membranes alone did not form a monolayer with ECs, whereas collagen-coated nanofibrous membranes did. Several concentrations of collagen in the gel coating promoted the formation of cell-cell junctional complexes, facilitated the deposition of laminin, and increased the focal contact organization of ECs. These results suggest the possible use of collagen-coated nanofibrous membranes for vascular tissue engineering applications and a vascular platform for organ-on-a-chip systems. PMID:27186924

  5. Adherence of Candida to cultured vascular endothelial cells: mechanisms of attachment and endothelial cell penetration.

    PubMed

    Rotrosen, D; Edwards, J E; Gibson, T R; Moore, J C; Cohen, A H; Green, I

    1985-12-01

    To elucidate the pathogenesis of hematogenous Candida infections, we developed an in vitro model of Candida adherence to and penetration of human endothelial cells. We enhanced or inhibited adherence in order to probe mechanisms of attachment. Adherence of Candida albicans showed a linear relation to Candida inoculum (range, 10(2)-10(5) cfu, r = .99, P less than .01) and exceeded that of less virulent Candida species and that of Saccharomyces cerevisiae (P less than .01). Candida immune serum blocked attachment (greater than 95% inhibition; P less than .001), however, this activity was abolished by immunoprecipitation of immune serum with C. albicans mannan (P less than .001) and was unaffected by immunoprecipitation with S. cerevisiae mannan or by adsorption with particulate chitin. Adherence was diminished by exposing C. albicans to heat (greater than 99% inhibition; P less than .01), UV light (98% inhibition; P less than .01), or sodium periodate (greater than 72% inhibition; P less than .01). An extract from heat-exposed C. albicans blocked adherence (greater than 51% inhibition; P less than .001). Transmission electron microscopy demonstrated that viable or killed Candida organisms were attached to endothelial cells, were enveloped by membrane processes from the endothelial cell surface, and were incorporated into the endothelial cells within phagosomes. Cytochalasin B blocked incorporation without blocking surface attachment. PMID:3905987

  6. Renal cell carcinoma alters endothelial receptor expression responsible for leukocyte adhesion

    PubMed Central

    Juengel, Eva; Krueger, Geraldine; Rutz, Jochen; Nelson, Karen; Werner, Isabella; Relja, Borna; Seliger, Barbara; Fisslthaler, Beate; Fleming, Ingrid; Tsaur, Igor

    2016-01-01

    Renal cell carcinoma (RCC) escapes immune recognition. To elaborate the escape strategy the influence of RCC cells on endothelial receptor expression and endothelial leukocyte adhesion was evaluated. Human umbilical vein endothelial cells (HUVEC) were co-cultured with the RCC cell line, Caki-1, with and without tumor necrosis factor (TNF)-alpha. Intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelial (E)-selectin, standard and variants (V) of CD44 were then analysed in HUVEC, using flow cytometry and Western blot analysis. To determine which components are responsible for HUVEC-Caki-1 interaction causing receptor alteration, Caki-1 membrane fragments versus cell culture supernatant were applied to HUVECS. Adhesion of peripheral blood lymphocytes (PBL) and polymorphonuclear neutrophils (PMN) to endothelium was evaluated by co-culture adhesion assays. Relevance of endothelial receptor expression for adhesion to endothelium was determined by receptor blockage. Co-culture of RCC and HUVECs resulted in a significant increase in endothelial ICAM-1, VCAM-1, E-selectin, CD44 V3 and V7 expression. Previous stimulation of HUVECs with TNF-alpha and co-cultivation with Caki-1 resulted in further elevation of endothelial CD44 V3 and V7 expression, whereas ICAM-1, VCAM-1 and E-selectin expression were significantly diminished. Since Caki-1 membrane fragments also caused these alterations, but cell culture supernatant did not, cell-cell contact may be responsible for this process. Blocking ICAM-1, VCAM-1, E-selectin or CD44 with respective antibodies led to a significant decrease in PBL and PMN adhesion to endothelium. Thus, exposing HUVEC to Caki-1 results in significant alteration of endothelial receptor expression and subsequent endothelial attachment of PBL and PMN. PMID:26943029

  7. Differentiation state determines neural effects on microvascular endothelial cells

    SciTech Connect

    Muffley, Lara A.; Pan, Shin-Chen; Smith, Andria N.; Ga, Maricar; Hocking, Anne M.; Gibran, Nicole S.

    2012-10-01

    Growing evidence indicates that nerves and capillaries interact paracrinely in uninjured skin and cutaneous wounds. Although mature neurons are the predominant neural cell in the skin, neural progenitor cells have also been detected in uninjured adult skin. The aim of this study was to characterize differential paracrine effects of neural progenitor cells and mature sensory neurons on dermal microvascular endothelial cells. Our results suggest that neural progenitor cells and mature sensory neurons have unique secretory profiles and distinct effects on dermal microvascular endothelial cell proliferation, migration, and nitric oxide production. Neural progenitor cells and dorsal root ganglion neurons secrete different proteins related to angiogenesis. Specific to neural progenitor cells were dipeptidyl peptidase-4, IGFBP-2, pentraxin-3, serpin f1, TIMP-1, TIMP-4 and VEGF. In contrast, endostatin, FGF-1, MCP-1 and thrombospondin-2 were specific to dorsal root ganglion neurons. Microvascular endothelial cell proliferation was inhibited by dorsal root ganglion neurons but unaffected by neural progenitor cells. In contrast, microvascular endothelial cell migration in a scratch wound assay was inhibited by neural progenitor cells and unaffected by dorsal root ganglion neurons. In addition, nitric oxide production by microvascular endothelial cells was increased by dorsal root ganglion neurons but unaffected by neural progenitor cells. -- Highlights: Black-Right-Pointing-Pointer Dorsal root ganglion neurons, not neural progenitor cells, regulate microvascular endothelial cell proliferation. Black-Right-Pointing-Pointer Neural progenitor cells, not dorsal root ganglion neurons, regulate microvascular endothelial cell migration. Black-Right-Pointing-Pointer Neural progenitor cells and dorsal root ganglion neurons do not effect microvascular endothelial tube formation. Black-Right-Pointing-Pointer Dorsal root ganglion neurons, not neural progenitor cells, regulate

  8. Equine Endothelial Cells Support Productive Infection of Equine Infectious Anemia Virus

    PubMed Central

    Maury, Wendy; Oaks, J. Lindsay; Bradley, Sarahann

    1998-01-01

    Previous cell infectivity studies have demonstrated that the lentivirus equine infectious anemia virus (EIAV) infects tissue macrophages in vivo and in vitro. In addition, some strains of EIAV replicate to high titer in vitro in equine fibroblasts and fibroblast cell lines. Here we report a new cell type, macrovascular endothelial cells, that is infectible with EIAV. We tested the ability of EIAV to infect purified endothelial cells isolated from equine umbilical cords and renal arteries. Infectivity was detected by cell supernatant reverse transcriptase positivity, EIAV antigen positivity within individual cells, and the detection of viral RNA by in situ hybridization. Virus could rapidly spread through the endothelial cultures, and the supernatants of infected cultures contained high titers of infectious virus. There was no demonstrable cell killing in infected cultures. Three of four strains of EIAV that were tested replicated in these cultures, including MA-1, a fibroblast-tropic strain, Th.1, a macrophage-tropic strain, and WSU5, a strain that is fibroblast tropic and can cause disease. Finally, upon necropsy of a WSU5-infected horse 4 years postinfection, EIAV-positive endothelial cells were detected in outgrowths of renal artery cultures. These findings identify a new cell type that is infectible with EIAV. The role of endothelial cell infection in the course of equine infectious anemia is currently unknown, but endothelial cell infection may be involved in the edema that can be associated with infection. Furthermore, the ability of EIAV to persistently infect endothelial cultures and the presence of virus in endothelial cells from a long-term carrier suggest that this cell type can serve as a reservoir for the virus during subclinical phases of infection. PMID:9765477

  9. Rapamycin inhibits re-endothelialization after percutaneous coronary intervention by impeding the proliferation and migration of endothelial cells and inducing apoptosis of endothelial progenitor cells.

    PubMed

    Liu, Hai-Tao; Li, Fei; Wang, Wen-Yong; Li, Xiao-Jing; Liu, Yi-Meng; Wang, Rui-An; Guo, Wen-Yi; Wang, Hai-Chang

    2010-01-01

    Endothelial-cell function is important in the healing of damaged endothelium after percutaneous coronary artery damage. In 3 different animal models, we sought to determine whether rapamycin (sirolimus) affects the proliferation and migration of endothelial cells and endothelial progenitor cells. First, after we implanted stents in dogs, we found that re-endothelialization was impeded more by drug-eluting stents than by bare-metal stents, 30 days after percutaneous coronary intervention. Second, in vitro in rats, we found that 1-100 ng/mL of rapamycin time- and dose-dependently inhibited proliferation over 72 hr (with effects evident as early as 24 hr) and also dose-dependently induced endothelial progenitor-cell apoptosis. Finally, in vivo in rats, we observed that vascular endothelial growth factor expression was decreased after 5 days of rapamycin treatment. We conclude that rapamycin impedes re-endothelialization after drug-eluting stent implantation by inhibiting the proliferation and migration of coronary endothelial cells, inducing endothelial progenitor-cell apoptosis, and decreasing vascular endothelial growth factor expression in the circulation. PMID:20401293

  10. Pancreatic-carcinoma-cell-derived pro-angiogenic factors can induce endothelial-cell differentiation of a subset of circulating CD34+ progenitors

    PubMed Central

    2013-01-01

    Background CD34+ progenitor cells comprise both hematopoietic and endothelial progenitor cells. Recent studies suggest that circulating endothelial progenitor cells are recruited into the angiogenic vascular system of several cancers, including pancreatic carcinoma, and that they correlate with clinical progress. However, whether endothelial progenitor cell mobilization occurs in response to cytokine release by tumor cells is still unclear. Methods The chemotactic- and/or differentiating-activities of the poorly-differentiated pancreatic carcinoma cell line PT45, and of the immortal H6c7 cell line, a line of near-normal pancreatic duct epithelial cells, on endothelial progenitor cells were investigated in vitro using circulating CD34+ as model. Results The study showed that Vascular Endothelial Growth Factor produced by PT45 cells and, at lesser extent, by H6c7 cells, predominantly chemoattract peripheral blood CD34+ expressing the type 2 relative receptor. Addition of PT45-conditioned medium to CD34+ cells, cultured under conditions supporting myeloid cell development, diverted the differentiation of a subset of these progenitor cells into cells expressing endothelial cell markers, such as CD146, CD105, VE-cadherin and von Willebrand Factor-related antigen. Moreover, these endothelial-like cells formed capillary networks in vitro, chiefly through the release of Angiopoietin-1 by PT45 cells. Conclusions The results demonstrate that pancreatic-carcinoma cells potentially attract circulating endothelial progenitor cells to the tumor site, by releasing high levels of pro-angiogenic factors such as Vascular Endothelial Growth Factor and Angiopoietin-1, and may direct the differentiation of these cell subsets of the CD34+ cell population into endothelial cells; the latter cells may become a component of the newly-formed vessels, contributing to angiogenesis-mediated tumor growth and metastasis. PMID:24341512

  11. Involvement of marrow-derived endothelial cells in vascularization.

    PubMed

    Larrivée, B; Karsan, A

    2007-01-01

    Until recently, the adult neovasculature was thought to arise only through angiogenesis, the mechanism by which new blood vessels form from preexisting vessels through endothelial cell migration and proliferation. However, recent studies have provided evidence that postnatal neovasculature can also arise though vasculogenesis, a process by which endothelial progenitor cells are recruited and differentiate into mature endothelial cells to form new blood vessels. Evidence for the existence of endothelial progenitors has come from studies demonstrating the ability of bone marrow-derived cells to incorporate into adult vasculature. However, the exact nature of endothelial progenitor cells remains controversial. Because of the lack of definitive markers of endothelial progenitors, the in vivo contribution of progenitor cells to physiological and pathological neovascularization remains unclear. Early studies reported that endothelial progenitor cells actively integrate into the adult vasculature and are critical in the development of many types of vascular-dependent disorders such as neoplastic progression. Moreover, it has been suggested that endothelial progenitor cells can be used as a therapeutic strategy aimed at promoting vascular growth in a variety of ischemic diseases. However, increasing numbers of studies have reported no clear contribution of endothelial progenitors in physiological or pathological angiogenesis. In this chapter, we discuss the origin of the endothelial progenitor cell in the embryo and adult, and we discuss the cell's link to the primitive hematopoietic stem cell. We also review the potential significance of endothelial progenitor cells in the formation of a postnatal vascular network and discuss the factors that may account for the current lack of consensus of the scientific community on this important issue. PMID:17554506

  12. Cancer cells remodel themselves and vasculature to overcome the endothelial barrier.

    PubMed

    Shenoy, Anitha K; Lu, Jianrong

    2016-10-01

    Metastasis refers to the spread of cancer cells from a primary tumor to distant organs mostly via the bloodstream. During the metastatic process, cancer cells invade blood vessels to enter circulation, and later exit the vasculature at a distant site. Endothelial cells that line blood vessels normally serve as a barrier to the movement of cells into or out of the blood. It is thus critical to understand how metastatic cancer cells overcome the endothelial barrier. Epithelial cancer cells acquire increased motility and invasiveness through epithelial-to-mesenchymal transition (EMT), which enables them to move toward vasculature. Cancer cells also express a variety of adhesion molecules that allow them to attach to vascular endothelium. Finally, cancer cells secrete or induce growth factors and cytokines to actively prompt vascular hyperpermeability that compromises endothelial barrier function and facilitates transmigration of cancer cells through the vascular wall. Elucidation of the mechanisms underlying metastatic dissemination may help develop new anti-metastasis therapeutics. PMID:25449784

  13. Sickle erythrocytes inhibit human endothelial cell DNA synthesis

    SciTech Connect

    Weinstein, R.; Zhou, M.A.; Bartlett-Pandite, A.; Wenc, K. )

    1990-11-15

    Patients with sickle cell anemia experience severe vascular occlusive phenomena including acute pain crisis and cerebral infarction. Obstruction occurs at both the microvascular and the arterial level, and the clinical presentation of vascular events is heterogeneous, suggesting a complex etiology. Interaction between sickle erythrocytes and the endothelium may contribute to vascular occlusion due to alteration of endothelial function. To investigate this hypothesis, human vascular endothelial cells were overlaid with sickle or normal erythrocytes and stimulated to synthesize DNA. The erythrocytes were sedimented onto replicate monolayers by centrifugation for 10 minutes at 17 g to insure contact with the endothelial cells. Incorporation of 3H-thymidine into endothelial cell DNA was markedly inhibited during contact with sickle erythrocytes. This inhibitory effect was enhanced more than twofold when autologous sickle plasma was present during endothelial cell labeling. Normal erythrocytes, with or without autologous plasma, had a modest effect on endothelial cell DNA synthesis. When sickle erythrocytes in autologous sickle plasma were applied to endothelial monolayers for 1 minute, 10 minutes, or 1 hour and then removed, subsequent DNA synthesis by the endothelial cells was inhibited by 30% to 40%. Although adherence of sickle erythrocytes to the endothelial monolayers was observed under these experimental conditions, the effect of sickle erythrocytes on endothelial DNA synthesis occurred in the absence of significant adherence. Hence, human endothelial cell DNA synthesis is partially inhibited by contact with sickle erythrocytes. The inhibitory effect of sickle erythrocytes occurs during a brief (1 minute) contact with the endothelial monolayers, and persists for at least 6 hours of 3H-thymidine labeling.

  14. Tumor and Endothelial Cell Hybrids Participate in Glioblastoma Vasculature

    PubMed Central

    El Hallani, Soufiane; Colin, Carole; El Houfi, Younas; Boisselier, Blandine; Marie, Yannick; Ravassard, Philippe; Labussière, Marianne; Mokhtari, Karima; Thomas, Jean-Léon; Delattre, Jean-Yves; Eichmann, Anne; Sanson, Marc

    2014-01-01

    Background. Recently antiangiogenic therapy with bevacizumab has shown a high but transient efficacy in glioblastoma (GBM). Indeed, GBM is one of the most angiogenic human tumors and endothelial proliferation is a hallmark of the disease. We therefore hypothesized that tumor cells may participate in endothelial proliferation of GBM. Materials and Methods. We used EGFR FISH Probe to detect EGFR amplification and anti-CD31, CD105, VE-cadherin, and vWF to identify endothelial cells. Endothelial and GBM cells were grown separately, labeled with GFP and DsRed lentiviruses, and then cocultured with or without contact. Results. In a subset of GBM tissues, we found that several tumor endothelial cells carry EGFR amplification, characteristic of GBM tumor cells. This observation was reproduced in vitro: when tumor stem cells derived from GBM were grown in the presence of human endothelial cells, a fraction of them acquired endothelial markers (CD31, CD105, VE-cadherin, and vWF). By transduction with GFP and DsRed expressing lentiviral vectors, we demonstrate that this phenomenon is due to cell fusion and not transdifferentiation. Conclusion. A fraction of GBM stem cells thus has the capacity to fuse with endothelial cells and the resulting hybrids may participate in tumor microvascular proliferation and in treatment resistance. PMID:24868550

  15. The expression of endothelial cell surface antigens by AIDS-associated Kaposi's sarcoma. Evidence for a vascular endothelial cell origin.

    PubMed Central

    Rutgers, J. L.; Wieczorek, R.; Bonetti, F.; Kaplan, K. L.; Posnett, D. N.; Friedman-Kien, A. E.; Knowles, D. M.

    1986-01-01

    The authors investigated 19 cases of Kaposi's sarcoma (KS) obtained from patients with the acquired immune deficiency syndrome (AIDS) for their expression of Factor VIII-related antigen (FVIIIRAg), HLA-DR (Ia) antigens, OKM1, and three distinctive vascular, but not lymphatic, endothelial-cell-associated antigens, E92, OKM5, and HCl. Antigen expression was demonstrated by immunoperoxidase staining of cryostat sections. FVIIIRAg is strongly expressed by the cells lining the vascular spaces (VCs) but is absent, weakly or focally, and variably expressed by the spindle cell (SC) component of KS. The VC component of each KS lesion examined strongly expressed E92, moderately expressed HCl, and weakly expressed OKM5. In contrast, the entire SC component of each KS lesion studied strongly expressed E92 and OKM5 and weakly expressed HCl. Neither the VCs nor the SCs expressed OKM1. These studies provide strong and compelling evidence for the vascular endothelial cell histogenesis of both the vascular and spindle cell components of KS, demonstrate the intertumor and intratumor phenotypic heterogeneity of KS, and suggest that monoclonal antibodies OKM5 and anti-E92 are the best currently available immunohistochemical markers for identifying the spindle cell component of AIDS-associated KS in cryostat sections. Images Figure 1 PMID:3953772

  16. TNFα and Endothelial Cells Modulate Notch Signaling in the Bone Marrow Microenvironment during Inflammation

    PubMed Central

    Fernandez, Luis; Rodriguez, Sonia; Huang, Hui; Chora, Angelo; Mumaw, Christin; Cruz, Eugenia; Pollok, Karen; Cristina, Filipa; Price, Joanne E.; Ferkowicz, Michael J.; Scadden, David T.; Clauss, Matthias; Cardoso, Angelo A.; Carlesso, Nadia

    2009-01-01

    Objective Homeostasis of the hematopoietic compartment is challenged and maintained during conditions of stress by mechanisms that are poorly defined. To understand how the bone marrow (BM) microenvironment influences hematopoiesis, we explored the role of Notch signaling and bone marrow endothelial cells in providing microenvironmental cues to hematopoietic cells in the presence of inflammatory stimuli. Methods The human BM endothelial cell line BMEC and primary human BM endothelial cells were analyzed for expression of Notch ligands and the ability to expand hematopoietic progenitors in an in vitro co-culture system. In vivo experiments were carried out to identify modulation of Notch signaling in BM endothelial and hematopoietic cells in mice challenged with TNFα or LPS, or in Tie2-tmTNFα transgenic mice characterized by constitutive TNFα activation. Results BM endothelial cells were found to express Jagged ligands and to greatly support progenitor’s colony-forming ability. This effect was markedly decreased by Notch antagonists and augmented by increasing levels of Jagged2. Physiologic upregulation of Jagged2 expression on BMEC was observed upon TNFα activation. Injection of TNFα or LPS upregulated 3 to 4 fold Jagged2 expression on murine BM endothelial cells in vivo and resulted in increased Notch activation on murine hematopoietic stem/progenitor cells. Similarly, constitutive activation of endothelial cells in Tie2-tmTNFα mice was characterized by increased expression of Jagged2 and by augmented Notch activation on hematopoietic stem/progenitor cells. Conclusions Our results provide the first evidence that BM endothelial cells promote expansion of hematopoietic progenitor cells by a Notch-dependent mechanism and that TNFα and LPS can modulate the levels of Notch ligand expression and Notch activation in the bone marrow microenvironment in vivo. PMID:18439488

  17. High-mobility group box 1 protein is implicated in advanced glycation end products–induced vascular endothelial growth factor A production in the rat retinal ganglion cell line RGC-5

    PubMed Central

    Lee, Jong-Jer; Hsiao, Chang-Chun; Yang, I-Hui; Chou, Ming-Huei; Wu, Chia-Lin; Wei, Yin-Chu; Chen, Chih-Hsin

    2012-01-01

    Purpose High-mobility group box 1 protein (HMGB1) has been reported to be a potent proangiogenic factor induced by inflammatory stress. In this study, we explore the role of HMGB1 in advanced glycation end products (AGEs)–induced vascular endothelial growth factor A (VEGF-A) production in rat retinal ganglion cell line 5 (RGC-5) cells. Methods The VEGF-A protein and mRNA levels in conditioned medium of RGC-5 cells incubated with AGE-modified BSA (AGE-BSA) were examined with real-time PCR and enzyme-linked immunosorbent assay (ELISA), and BSA-treated cells were used as controls. The expression of HMGB1, c-Jun N-terminal kinase (JNK), extracellular-signal-regulated kinase (ERK), and p38 mitogen-activated protein kinase (p38 MAPK) was assessed with immunofluorescence and western blot analysis. Reactive oxidative species (ROS) were detected with flow cytometry measurements of peroxide-dependent oxidation of 2′-7′-dichlorofluorescein-diacetate (DCFH-DA). N-Acetyl-L-cysteine (NAC), glycyrrhizin (GZ), and SP600125 were used to block ROS, HMGB1, and JNK, respectively. Results Compared with the BSA controls, the RGC-5 cells incubated with AGE-BSA showed a dose- and time-dependent increase in VEGF-A mRNA and VEGF-A protein secretion in the supernatant, with the highest levels achieved at 24 h. AGE-BSA stimulated a significant release of HMGB1 in the supernatant and a significant increase of intracellular ROS production at 3 h. NAC blocked HMGB1 production in a dose-dependent manner. Blocking with GZ, NAC, and JNK significantly suppressed AGE-induced VEGF-A production. Conclusions HMGB1 is implicated in the production of VEGF-A in retinal ganglion cell line-5 (RGC-5). Blocking HMGB1, ROS, or the JNK pathway may attenuate VEGF-A production, suggesting HMGB1 and related signaling molecules play a role in diabetic retinopathy. PMID:22511847

  18. Lysophosphatidic acid stimulates thrombomodulin lectin-like domain shedding in human endothelial cells

    SciTech Connect

    Wu Hualin; Lin ChiIou; Huang Yuanli; Chen, Pin-Shern; Kuo, Cheng-Hsiang; Chen, Mei-Shing; Wu, G.C.-C.; Shi, G.-Y.; Yang, H.-Y.; Lee Hsinyu

    2008-02-29

    Thrombomodulin (TM) is an anticoagulant glycoprotein highly expressed on endothelial cell surfaces. Increased levels of soluble TM in circulation have been widely accepted as an indicator of endothelial damage or dysfunction. Previous studies indicated that various proinflammatory factors stimulate TM shedding in various cell types such as smooth muscle cells and epithelial cells. Lysophosphatidic acid (LPA) is a bioactive lipid mediator present in biological fluids during endothelial damage or injury. In the present study, we first observed that LPA triggered TM shedding in human umbilical vein endothelial cells (HUVECs). By Cyflow analysis, we showed that the LPA-induced accessibility of antibodies to the endothelial growth factor (EGF)-like domain of TM is independent of matrix metalloproteinases (MMPs), while LPA-induced TM lectin-like domain shedding is MMP-dependent. Furthermore, a stable cell line expressing TM without its lectin-like domain exhibited a higher cell proliferation rate than a stable cell line expressing full-length TM. These results imply that LPA induces TM lectin-like domain shedding, which might contribute to the exposure of its EGF-like domain for EGF receptor (EGFR) binding, thereby stimulating subsequent cell proliferation. Based on our findings, we propose a novel mechanism for the exposure of TM EGF-like domain, which possibly mediates LPA-induced EGFR transactivation.

  19. Hypoxia-induced mitogenic factor enhances angiogenesis by promoting proliferation and migration of endothelial cells

    SciTech Connect

    Tong Qiangsong; Zheng Liduan; Li Bo; Wang Danming; Huang Chuanshu; Matuschak, George M.; Li Dechun . E-mail: dli2@slu.edu

    2006-11-01

    Our previous studies have indicated that hypoxia-induced mitogenic factor (HIMF) has angiogenic properties in an in vivo matrigel plug model and HIMF upregulates expression of vascular endothelial growth factor (VEGF) in mouse lungs and cultured lung epithelial cells. However, whether HIMF exerts angiogenic effects through modulating endothelial cell function remains unknown. In this study, mouse aortic rings cultured with recombinant HIMF protein resulted in enhanced vascular sprouting and increased endothelial cell spreading as confirmed by Dil-Ac-LDL uptake, von Willebrand factor and CD31 staining. In cultured mouse endothelial cell line SVEC 4-10, HIMF dose-dependently enhanced cell proliferation, in vitro migration and tubulogenesis, which was not attenuated by SU1498, a VEGFR2/Flk-1 receptor tyrosine kinase inhibitor. Moreover, HIMF stimulation resulted in phosphorylation of Akt, p38 and ERK1/2 kinases in SVEC 4-10 cells. Treatment of mouse aortic rings and SVEC 4-10 cells with LY294002, but not SB203580, PD098059 or U0126, abolished HIMF-induced vascular sprouting and angiogenic responses. In addition, transfection of a dominant-negative mutant of phosphatidylinositol 3-kinase (PI-3K), {delta}p85, blocked HIMF-induced phosphorylation of Akt, endothelial activation and tubulogenesis. These results indicate that HIMF enhances angiogenesis by promoting proliferation and migration of endothelial cells via activation of the PI-3K/Akt pathways.

  20. Basal and inducible anti-inflammatory epoxygenase activity in endothelial cells

    SciTech Connect

    Askari, Ara A.; Thomson, Scott; Edin, Matthew L.; Lih, Fred B.; Zeldin, Darryl C.; Bishop-Bailey, David

    2014-04-04

    Highlights: • We examined epoxygenase product formation and regulation in endothelial cells. • The epoxygenase CYP2J2 is an LPS (TLR-4) inducible enzyme in endothelial cells. • The endothelial cell line EA.Hy926 synthesises epoxygenase products. • Inhibition of endothelial epoxygenases increases TNFα secretion. • Soluble epoxide hydrolase inhibitors reduce inflammation-induced TNFα and NFκB. - Abstract: The roles of CYP lipid-metabolizing pathways in endothelial cells are poorly understood. Human endothelial cells expressed CYP2J2 and soluble epoxide hydrolase (sEH) mRNA and protein. The TLR-4 agonist LPS (1 μg/ml; 24 h) induced CYP2J2 but not sEH mRNA and protein. LC–MS/MS analysis of the stable commonly used human endothelial cell line EA.Hy926 showed active epoxygenase and epoxide hydrolase activity: with arachidonic acid (stable epoxide products 5,6-DHET, and 14,15-DHET), linoleic acid (9,10-EPOME and 12,13-EPOME and their stable epoxide hydrolase products 9,10-DHOME and 12,13-DHOME), docosahexaenoic acid (stable epoxide hydrolase product 19,20-DiHDPA) and eicosapentaenoic acid (stable epoxide hydrolase product 17,18-DHET) being formed. Inhibition of epoxygenases using either SKF525A or MS-PPOH induced TNFα release, but did not affect LPS, IL-1β, or phorbol-12-myristate-13-acetate (PMA)-induced TNFα release. In contrast, inhibition of soluble epoxide hydrolase by AUDA or TPPU inhibited basal, LPS, IL-1β and PMA induced TNFα release, and LPS-induced NFκB p65 nuclear translocation. In conclusion, human endothelial cells contain a TLR-4 regulated epoxygenase CYP2J2 and metabolize linoleic acid > eicosapentaenoic acid > arachidonic acid > docosahexaenoic acid to products with anti-inflammatory activity.

  1. Characterization of iron uptake from transferrin by murine endothelial cells.

    PubMed

    Hallmann, R; Savigni, D L; Morgan, E H; Baker, E

    2000-01-01

    Iron is required by the brain for normal function, however, the mechanisms by which it crosses the blood-brain barrier (BBB) are poorly understood. The uptake and efflux of transferrin (Tf) and Fe by murine brain-derived (bEND3) and lymph node-derived (m1END1) endothelial cell lines was compared. The effects of iron chelators, metabolic inhibitors and the cellular activators, lipopolysaccharide (LPS) and tumour necrosis factor-alpha (TNF-alpha), on Tf and Fe uptake were investigated. Cells were incubated with 59Fe-125I-Tf; Fe uptake was shown to increase linearly over time for both cell lines, while Tf uptake reached a plateau within 2 h. Both Tf and Fe uptake were saturable. bEND3 cells were shown to have half as many Tf receptors as m1END1 cells, but the mean cycling times of a Tf molecule were the same. Tf and Fe efflux from the cells were measured over time, revealing that after 2 h only 25% of the Tf but 80% of the Fe remained associated with the cells. Of 7 iron chelators, only deferriprone (L1) markedly decreased Tf uptake. However, Fe uptake was reduced by more than 50% by L1, pyridoxal isonicotinoyl hydrazone (PIH) and desferrithiocin (DFT). The cellular activators TNF-alpha or LPS had little effect on Tf turnover, but they accelerated Fe uptake in both endothelial cell types. Phenylarsenoxide (PhAsO) and N-ethyl maleimide (NEM), inhibitors of Tf endocytosis, reduced both Tf and Fe uptake in both cell lines, while bafilomycin A1, an inhibitor of endosomal acidification, reduced Fe uptake but did not affect Tf uptake. The results suggest that Tf and Fe uptake by both bEND3 and m1END1 is via receptor-mediated endocytosis with release of Fe from Tf within the cell and recycling of apo-Tf. On the basis of Tf- and Fe-metabolism both cell lines are similar and therefore well suited for use in in vitro models for Fe transport across the BBB. PMID:10865941

  2. Evaluation of the cytotoxic effects of humid lightweight coal ash derived from the disposal of waste on normal human keratinocyte and endothelial cell lines in 2-D and 3-D culture.

    PubMed

    Scanarotti, Chiara; Vernazza, Stefania; Brignone, Massimiliano; Danailova, Jenia; Pronzato, Maria A; Bassi, Anna M

    2013-12-01

    The presence of waste in the environment has frequently been indicated as a significant risk to human health. Therefore, landfill sites and the disposal of urban solid and non-hazardous waste by incineration are subject to much environmental monitoring, in addition to the regulations already in place. However, little action has been taken, and consequently no specific legislation exists, in relation to the assessment of the real biological risk of various substances, including chemical mixtures and ashes, derived from the incineration processes. This study assessed the cytotoxic potential of humid lightweight coal ash (LA) derived from incineration processes and waste management, on two cell lines: NCTC 2544 normal human keratinocytes and HECV endothelial cells. To reach this goal and to assess more-realistic methods for animal replacement, we employed different in vitro experimental approaches: acute and longer exposure to LA, by direct and indirect contact (0-2mg/ml and 16mg, respectively), both in 2-D and 3-D cultures. In 2-D HECV cultures, we observed a decrease in the viability index, but only during direct contact with LA doses higher than 0.1mg/ml. Moreover, some striking differences in cytotoxicity were observed between the 2-D and 3-D models. Taken together, these observations indicate that, for studying pollutant toxicity during longer exposure times, 3-D cultures in direct contact with the pollutant seem to offer a more suitable approach - they mimic the in vivo behaviour of cells more realistically and under strictly controlled conditions. Thus, in readiness for possible forthcoming European regulations, we believe that the proposed study, even in its preliminary phase, can provide new advice on the assessment of the toxic and biological potential of particular chemical compounds derived from waste management processes. PMID:24512233

  3. Cellular Dewetting: Opening of Macroapertures in Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Gonzalez-Rodriguez, David; Maddugoda, Madhavi P.; Stefani, Caroline; Janel, Sebastien; Lafont, Frank; Cuvelier, Damien; Lemichez, Emmanuel; Brochard-Wyart, Françoise

    2012-05-01

    Pathogenic bacteria can cross from blood vessels to host tissues by opening transendothelial cell macroapertures (TEMs). To induce TEM opening, bacteria intoxicate endothelial cells with proteins that disrupt the contractile cytoskeletal network. Cell membrane tension is no longer resisted by contractile fibers, leading to the opening of TEMs. Here we model the opening of TEMs as a new form of dewetting. While liquid dewetting is irreversible, we show that cellular dewetting is transient. Our model predicts the minimum radius for hole nucleation, the maximum TEM size, and the dynamics of TEM opening, in good agreement with experimental data. The physical model is then coupled with biological experimental data to reveal that the protein missing in metastasis (MIM) controls the line tension at the rim of the TEM and opposes its opening.

  4. Prolonged cyclic strain inhibits human endothelial cell growth.

    PubMed

    Peyton, Kelly J; Liu, Xiao-ming; Durante, William

    2016-01-01

    The vascular endothelium is continuously exposed to cyclic mechanical strain due to the periodic change in vessel diameter as a result of pulsatile blood flow. Since emerging evidence indicates the cyclic strain plays an integral role in regulating endothelial cell function, the present study determined whether application of a physiologic regimen of cyclic strain (6% at 1 hertz) influences the proliferation of human arterial endothelial cells. Prolonged exposure of human dermal microvascular or human aortic endothelial cells to cyclic strain for up to 7 days resulted in a marked decrease in cell growth. The strain-mediated anti-proliferative effect was associated with the arrest of endothelial cells in the G2/M phase of the cell cycle, did not involve cell detachment or cytotoxicity, and was due to the induction of p21. Interestingly, the inhibition in endothelial cell growth was independent of the strain regimen since prolonged application of constant or intermittent 6% strain was also able to block endothelial cell proliferation. The ability of chronic physiologic cyclic strain to inhibit endothelial cell growth represents a previously unrecognized mechanism by which hemodynamic forces maintain these cells in a quiescent, non-proliferative state. PMID:26709656

  5. Ionizing Radiation-Induced Endothelial Cell Senescence and Cardiovascular Diseases.

    PubMed

    Wang, Yingying; Boerma, Marjan; Zhou, Daohong

    2016-08-01

    Exposure to ionizing radiation induces not only apoptosis but also senescence. While the role of endothelial cell apoptosis in mediating radiation-induced acute tissue injury has been extensively studied, little is known about the role of endothelial cell senescence in the pathogenesis of radiation-induced late effects. Senescent endothelial cells exhibit decreased production of nitric oxide and expression of thrombomodulin, increased expression of adhesion molecules, elevated production of reactive oxygen species and inflammatory cytokines and an inability to proliferate and form capillary-like structures in vitro. These findings suggest that endothelial cell senescence can lead to endothelial dysfunction by dysregulation of vasodilation and hemostasis, induction of oxidative stress and inflammation and inhibition of angiogenesis, which can potentially contribute to radiation-induced late effects such as cardiovascular diseases (CVDs). In this article, we discuss the mechanisms by which radiation induces endothelial cell senescence, the roles of endothelial cell senescence in radiation-induced CVDs and potential strategies to prevent, mitigate and treat radiation-induced CVDs by targeting senescent endothelial cells. PMID:27387862

  6. Ionizing Radiation-Induced Endothelial Cell Senescence and Cardiovascular Diseases

    PubMed Central

    Wang, Yingying; Boerma, Marjan; Zhou, Daohong

    2016-01-01

    Exposure to ionizing radiation induces not only apoptosis but also senescence. While the role of endothelial cell apoptosis in mediating radiation-induced acute tissue injury has been extensively studied, little is known about the role of endothelial cell senescence in the pathogenesis of radiation-induced late effects. Senescent endothelial cells exhibit decreased production of nitric oxide and expression of thrombomodulin, increased expression of adhesion molecules, elevated production of reactive oxygen species and inflammatory cytokines and an inability to proliferate and form capillary-like structures in vitro. These findings suggest that endothelial cell senescence can lead to endothelial dysfunction by dysregulation of vasodilation and hemostasis, induction of oxidative stress and inflammation and inhibition of angiogenesis, which can potentially contribute to radiation-induced late effects such as cardiovascular diseases (CVDs). In this article, we discuss the mechanisms by which radiation induces endothelial cell senescence, the roles of endothelial cell senescence in radiation-induced CVDs and potential strategies to prevent, mitigate and treat radiation-induced CVDs by targeting senescent endothelial cells. PMID:27387862

  7. Endothelial derived factors inhibit anoikis of head and neck cancer stem cells

    PubMed Central

    Campos, Marcia S.; Neiva, Kathleen G.; Meyers, Kristy A.; Krishnamurthy, Sudha; Nör, Jacques E.

    2011-01-01

    Recent evidence demonstrated that cancer stem cells reside in close proximity to blood vessels in human head and neck squamous cell carcinomas (HNSCC). These findings suggest the existence of a supporting perivascular niche for cancer stem cells. Objective The purpose of this study was to evaluate the effect of endothelial cell-secreted factors on the behavior of head and neck cancer stem-like cells (HNCSC). Materials and methods HNCSC were identified by sorting UM-SCC-22A (cell line derived from a primary squamous cell carcinoma of the oropharynx) and UM-SCC-22B (derived from the metastatic lymph node of the same patient) for CD44 expression and ALDH (aldehyde dehydrogenase) activity. HNCSC (ALDH+CD44+) and control (ALDH−CD44−) cells were cultured in ultra-low attachment plates in presence of conditioned medium from primary human endothelial cells. Results ALDH+CD44+ generated more orospheres than control cells when cultured in suspension. The growth factor milieu secreted by endothelial cells protected HNCSC against anoikis. Mechanistic studies revealed that endothelial cell-secreted vascular endothelial growth factor (VEGF) induces proliferation of HNCSC derived from primary UM-SCC-22A, but not from the metastatic UM-SCC-22B. Likewise, blockade of VEGF abrogated endothelial cell-induced Akt phosphorylation in HNCSC derived from UM-SCC-22A while it had a modest effect in Akt phosphorylation in HNCSC from UM-SCC-22B. Conclusion This study revealed that endothelial cells initiate a crosstalk that protect head and neck cancer stem cells against anoikis, and suggest that therapeutic interference with this crosstalk might be beneficial for patients with head and neck cancer. PMID:22014666

  8. Cilostazol suppresses angiotensin II-induced apoptosis in endothelial cells

    PubMed Central

    SHI, MIAO-QIAN; SU, FEI-FEI; XU, XUAN; LIU, XIONG-TAO; WANG, HONG-TAO; ZHANG, WEI; LI, XUE; LIAN, CHENG; ZHENG, QIANG-SUN; FENG, ZHI-CHUN

    2016-01-01

    Patients with essential hypertension undergo endothelial dysfunction, particularly in the conduit arteries. Cilostazol, a type III phosphodiesterase inhibitor, serves a role in the inhibition of platelet aggregation and it is widely used in the treatment of peripheral vascular diseases. Previous studies have suggested that cilostazol suppresses endothelial dysfunction; however, it remains unknown whether cilostazol protects the endothelial function in essential hypertension. The aim of the present study was to investigate whether, and how, cilostazol suppresses angiotensin II (angII)-induced endothelial dysfunction. Human umbilical vein endothelial cells (HUVECs) and Sprague Dawley rats were exposed to angII and treated with cilostazol. Endothelial cell apoptosis and function, nitric oxide and superoxide production, phosphorylation (p) of Akt, and caspase-3 protein expression levels were investigated. AngII exposure resulted in the apoptosis of endothelial cells in vitro and in vivo. In vitro, cilostazol significantly suppressed the angII-induced apoptosis of HUVECs; however, this effect was reduced in the presence of LY294002, a phosphoinositide 3 kinase (PI3K) inhibitor. Furthermore, cilostazol suppressed the angII-induced p-Akt downregulation and cleaved caspase-3 upregulation. These effects were also alleviated by LY294002. In vivo, cilostazol suppressed the angII-induced endothelial cell apoptosis and dysfunction. Cilostazol was also demonstrated to partially reduced the angII-induced increase in superoxide production. The results of the present study suggested that cilostazol suppresses endothelial apoptosis and dysfunction by modulating the PI3K/Akt pathway. PMID:26862035

  9. Low-level laser irradiation effect on endothelial cells under conditions of hyperglycemia.

    PubMed

    Góralczyk, Krzysztof; Szymańska, Justyna; Szot, Katarzyna; Fisz, Jacek; Rość, Danuta

    2016-07-01

    Diabetes mellitus is considered to be a very serious lifestyle disease leading to cardiovascular complications and impaired wound healing observed in the diabetic foot syndrome. Chronic hyperglycemia is the source of the endothelial activation. The inflammatory process in diabetes is associated with the secretion of inflammatory cytokines by endothelial cells, e.g., tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). The method of phototherapy using laser beam of low power (LLLT-low-level laser therapy) effectively supports the conventional treatment of diabetic vascular complications such as diabetic foot syndrome. The aim of our study was to evaluate the effect of low-power laser irradiation at two wavelengths (635 and 830 nm) on the secretion of inflammatory factors (TNF-α and IL-6) by the endothelial cell culture-HUVEC line (human umbilical vein endothelial cell)-under conditions of hyperglycemia. It is considered that adverse effects of hyperglycemia on vascular endothelial cells may be corrected by the action of LLLT, especially with the wavelength of 830 nm. It leads to the reduction of TNF-α concentration in the supernatant and enhancement of cell proliferation. Endothelial cells play an important role in the pathogenesis of diabetes; however, a small number of studies evaluate an impact of LLLT on these cells under conditions of hyperglycemia. Further work on this subject is warranted. PMID:26861982

  10. Endothelial Progenitor Cells in Diabetic Retinopathy

    PubMed Central

    Lois, Noemi; McCarter, Rachel V.; O’Neill, Christina; Medina, Reinhold J.; Stitt, Alan W.

    2014-01-01

    Diabetic retinopathy (DR) is a leading cause of visual impairment worldwide. Patients with DR may irreversibly lose sight as a result of the development of diabetic macular edema (DME) and/or proliferative diabetic retinopathy (PDR); retinal blood vessel dysfunction and degeneration plays an essential role in their pathogenesis. Although new treatments have been recently introduced for DME, including intravitreal vascular endothelial growth factor inhibitors (anti-VEGFs) and steroids, a high proportion of patients (~40–50%) do not respond to these therapies. Furthermore, for people with PDR, laser photocoagulation remains a mainstay therapy despite this being an inherently destructive procedure. Endothelial progenitor cells (EPCs) are a low-frequency population of circulating cells known to be recruited to sites of vessel damage and tissue ischemia where they promote vascular healing and re-perfusion. A growing body of evidence suggests that the number and function of EPCs are altered in patients with varying degrees of diabetes duration, metabolic control, and in the presence or absence of DR. Although there are no clear-cut outcomes from these clinical studies, there is mounting evidence that some EPC sub-types may be involved in the pathogenesis of DR and may also serve as biomarkers for disease progression and stratification. Moreover, some EPC sub-types have considerable potential as therapeutic modalities for DME and PDR in the context of cell therapy. This study presents basic clinical concepts of DR and combines this with a general insight on EPCs and their relation to future directions in understanding and treating this important diabetic complication. PMID:24782825

  11. Senescent endothelial cells: Potential modulators of immunosenescence and ageing.

    PubMed

    Pantsulaia, Ia; Ciszewski, Wojciech Michal; Niewiarowska, Jolanta

    2016-08-01

    Recent studies have demonstrated that the accumulation of senescent endothelial cells may be the primary cause of cardiovascular diseases. Because of their multifunctional properties, endothelial cells actively take part in stimulating the immune system and inflammation. In addition, ageing is characterized by the progressive deterioration of immune cells and a decline in the activation of the immune response. This results in a loss of the primary function of the immune system, which is eliminating damaged/senescent cells and neutralizing potential sources of harmful inflammatory reactions. In this review, we discuss cellular senescence and the senescence-associated secretory phenotype (SASP) of endothelial cells and summarize the link between endothelial cells and immunosenescence. We describe the possibility that age-related changes in Toll-like receptors (TLRs) and microRNAs can affect the phenotypes of senescent endothelial cells and immune cells via a negative feedback loop aimed at restraining the excessive pro-inflammatory response. This review also addresses the following questions: how do senescent endothelial cells influence ageing or age-related changes in the inflammatory burden; what is the connection between ECs and immunosenescence, and what are the crucial hypothetical pathways linking endothelial cells and the immune system during ageing. PMID:27235855

  12. Endothelial Cell Density to Predict Endothelial Graft Failure After Penetrating Keratoplasty

    PubMed Central

    Lass, Jonathan H.; Sugar, Alan; Benetz, Beth Ann; Beck, Roy W.; Dontchev, Mariya; Gal, Robin L.; Kollman, Craig; Gross, Robert; Heck, Ellen; Holland, Edward J.; Mannis, Mark J.; Raber, Irving; Stark, Walter; Stulting, R. Doyle

    2010-01-01

    Objective To determine whether preoperative and/or postoperative central endothelial cell density (ECD) and its rate of decline postoperatively are predictive of graft failure caused by endothelial decompensation following penetrating keratoplasty to treat a moderate-risk condition, principally, Fuchs dystrophy or pseudophakic corneal edema. Methods In a subset of Cornea Donor Study participants, a central reading center determined preoperative and postoperative ECD from available specular images for 17 grafts that failed because of endothelial decompensation and 483 grafts that did not fail. Results Preoperative ECD was not predictive of graft failure caused by endothelial decompensation (P = .91). However, the 6-month ECD was predictive of subsequent failure (P < .001). Among those that had not failed within the first 6 months, the 5-year cumulative incidence (±95% confidence interval) of failure was 13% (±12%) for the 33 participants with a 6-month ECD of less than 1700 cells/mm2 vs 2%(±3%) for the 137 participants with a 6-monthECDof 2500 cells/mm2 or higher. After 5 years’ follow-up, 40 of 277 participants (14%) with a clear graft had an ECD below 500 cells/mm2. Conclusions Preoperative ECD is unrelated to graft failure from endothelial decompensation, whereas there is a strong correlation of ECD at 6 months with graft failure from endothelial decompensation. A graft can remain clear after 5 years even when the ECD is below 500 cells/mm2. PMID:20065219

  13. Brugia malayi Asparaginyl - tRNA Synthetase Stimulates Endothelial Cell Proliferation, Vasodilation and Angiogenesis

    PubMed Central

    D, Jeeva Jothi; Dhanraj, Muthu; Solaiappan, Shanmugam; Sivanesan, Sanjana; Kron, Michael; Dhanasekaran, Anuradha

    2016-01-01

    A hallmark of chronic infection with lymphatic filarial parasites is the development of lymphatic disease which often results in permanent vasodilation and lymphedema, but all of the mechanisms by which filarial parasites induce pathology are not known. Prior work showed that the asparaginyl-tRNA synthetase (BmAsnRS) of Brugia malayi, an etiological agent of lymphatic filariasis, acts as a physiocrine that binds specifically to interleukin-8 (IL-8) chemokine receptors. Endothelial cells are one of the many cell types that express IL-8 receptors. IL-8 also has been reported previously to induce angiogenesis and vasodilation, however, the effect of BmAsnRS on endothelial cells has not been reported. Therefore, we tested the hypothesis that BmAsnRS might produce physiological changes in endothelial by studying the in vitro effects of BmAsnRS using a human umbilical vein cell line EA.hy926 and six different endothelial cell assays. Our results demonstrated that BmAsnRS produces consistent and statistically significant effects on endothelial cells that are identical to the effects of VEGF, vascular endothelial growth factor. This study supports the idea that new drugs or immunotherapies that counteract the adverse effects of parasite-derived physiocrines may prevent or ameliorate the vascular pathology observed in patients with lymphatic filariasis. PMID:26751209

  14. Endothelial Cell Integrin Laminin Receptor Expression in Multiple Sclerosis Lesions

    PubMed Central

    Sobel, Raymond A.; Hinojoza, Julian R.; Maeda, Atsuko; Chen, Michael

    1998-01-01

    Laminin, a major glycoprotein component of vessel basement membranes, is recognized by β1- and β3-integrins expressed on endothelial cells. To determine how endothelial cell integrins might function in multiple sclerosis (MS) lesions, integrin laminin receptors and laminin were analyzed in central nervous system samples from MS patients and controls by immunohistochemistry. In active MS lesions, endothelial cell VLA-6 and β1 subunits were decreased compared to controls whereas αv subunit and VLA-1 were increased. In chronic inactive lesions β1, VLA-6 and αv were the same as controls but VLA-1 remained increased. α3 subunit was constant in all samples. By immunoelectron microscopy VLA-1, VLA-6, β1, and laminin were distributed throughout endothelial cells; αv was adjacent to and on luminal surfaces; αv and VLA-1 were on intercellular junctions. These results indicate distinct regulation and functions of these integrins in different lesion stages. In active lesions decreased endothelial cell β1/VLA-6 could result in their detachment from laminin thereby facilitating leukocyte transvascular migration and blood-brain barrier breakdown. αv and VLA-1 on intercellular junctions may participate in re-establishing vessel integrity after leukocyte migration. Luminal surface αv also likely binds intraluminal ligands and cells. In chronic inactive plaques persistently elevated endothelial cell VLA-1 correlates with longstanding endothelial cell and blood-brain barrier dysfunction. PMID:9708801

  15. Antiproliferative effect of elevated glucose in human microvascular endothelial cells

    NASA Technical Reports Server (NTRS)

    Kamal, K.; Du, W.; Mills, I.; Sumpio, B. E.

    1998-01-01

    Diabetic microangiopathy has been implicated as a fundamental feature of the pathological complications of diabetes including retinopathy, neuropathy, and diabetic foot ulceration. However, previous studies devoted to examining the deleterious effects of elevated glucose on the endothelium have been performed largely in primary cultured cells of macrovessel origin. Difficulty in the harvesting and maintenance of microvascular endothelial cells in culture have hindered the study of this relevant population. Therefore, the objective of this study was to characterize the effect of elevated glucose on the proliferation and involved signaling pathways of an immortalized human dermal microvascular endothelial cell line (HMEC-1) that possess similar characteristics to their in vivo counterparts. Human dermal microvascular endothelial cells (HMEC-1) were grown in the presence of normal (5 mM) or high D-glucose (20 mM) for 14 days. The proliferative response of HMEC-1 was compared under these conditions as well as the cAMP and PKC pathways by in vitro assays. Elevated glucose significantly inhibited (P < 0.05) HMEC-1 proliferation after 7, 10, and 14 days. This effect was not mimicked by 20 mM mannitol. The antiproliferative effect was more pronounced with longer exposure (1-14 days) to elevated glucose and was irreversible 4 days after a 10-day exposure. The antiproliferative effect was partially reversed in the presence of a PKA inhibitor, Rp-cAMP (10-50 microM), and/or a PKC inhibitor, Calphostin C (10 nM). HMEC-1 exposed to elevated glucose (20 mM) for 14 days caused an increase in cyclic AMP accumulation, PKA, and PKC activity but was not associated with the activation of downstream events such as CRE and AP-1 binding activity. These data support the hypothesis that HMEC-1 is a suitable model to study the deleterious effects of elevated glucose on microvascular endothelial cells. Continued studies with HMEC-1 may prove advantageous in delineation of the molecular

  16. Defining minimum essential factors to derive highly pure human endothelial cells from iPS/ES cells in an animal substance-free system.

    PubMed

    Wu, Yu-Ting; I-Shing Yu; Tsai, Kuen-Jer; Shih, Chien-Yu; Hwang, Shiaw-Min; Su, Ih-Jen; Chiang, Po-Min

    2015-01-01

    It is desirable to obtain unlimited supplies of endothelial cells for research and therapeutics. However, current methods of deriving endothelial cells from humans suffer from issues, such as limited supplies, contamination from animal substances, and lengthy/complicated procedures. In this article we developed a way to differentiate human iPS and ES cells to highly pure endothelial cells in 5 days. The chemically defined system is robust, easy to perform, and free of animal substances. Using the system, we verified that combined TGFβ and canonical Wnt agonists are essential and sufficient for iPS/ES cell-to-mesoderm transition. Besides, VEGF-KDR signaling alone is required for endothelial formation at high density while supplementation with FGF allows for colonial endothelial differentiation. Finally, anti-adsorptive agents could enrich the endothelial output by allowing selective attachment of the endothelial precursors. The system was validated to work on multiple iPS/ES cells lines to produce endothelial cells capable of forming capillary-like structures in vitro and integrating into host vasculature in vivo. In sum, the simple yet robust differentiation system permits the unlimited supply of human endothelial cells. The defined and animal substance-free nature of the system is compatible with clinical applications and characterization of endothelial differentiation in an unbiased manner. PMID:25864432

  17. JunB is required for endothelial cell morphogenesis by regulating core-binding factor β

    PubMed Central

    Licht, Alexander H.; Pein, Oliver T.; Florin, Lore; Hartenstein, Bettina; Reuter, Hendrik; Arnold, Bernd; Lichter, Peter; Angel, Peter; Schorpp-Kistner, Marina

    2006-01-01

    The molecular mechanism triggering the organization of endothelial cells (ECs) in multicellular tubules is mechanistically still poorly understood. We demonstrate that cell-autonomous endothelial functions of the AP-1 subunit JunB are required for proper endothelial morphogenesis both in vivo in mouse embryos with endothelial-specific ablation of JunB and in in vitro angiogenesis models. By cDNA microarray analysis, we identified core-binding factor β (CBFβ), which together with the Runx proteins forms the heterodimeric core-binding transcription complex CBF, as a novel JunB target gene. In line with our findings, expression of the CBF target MMP-13 was impaired in JunB-deficient ECs. Reintroduction of CBFβ into JunB-deficient ECs rescued the tube formation defect and MMP-13 expression, indicating an important role for CBFβ in EC morphogenesis. PMID:17158955

  18. The impact of microgravity and hypergravity on endothelial cells.

    PubMed

    Maier, Jeanette A M; Cialdai, Francesca; Monici, Monica; Morbidelli, Lucia

    2015-01-01

    The endothelial cells (ECs), which line the inner surface of vessels, play a fundamental role in maintaining vascular integrity and tissue homeostasis, since they regulate local blood flow and other physiological processes. ECs are highly sensitive to mechanical stress, including hypergravity and microgravity. Indeed, they undergo morphological and functional changes in response to alterations of gravity. In particular microgravity leads to changes in the production and expression of vasoactive and inflammatory mediators and adhesion molecules, which mainly result from changes in the remodelling of the cytoskeleton and the distribution of caveolae. These molecular modifications finely control cell survival, proliferation, apoptosis, migration, and angiogenesis. This review summarizes the state of the art on how microgravity and hypergravity affect cultured ECs functions and discusses some controversial issues reported in the literature. PMID:25654101

  19. Tumor angiogenesis--characteristics of tumor endothelial cells.

    PubMed

    Hida, Kyoko; Maishi, Nako; Torii, Chisaho; Hida, Yasuhiro

    2016-04-01

    Tumor blood vessels provide nutrition and oxygen to the tumor, resulting in tumor progression. They also act as gatekeepers, inducing tumor metastasis. Thus, targeting tumor blood vessels is an important strategy in cancer therapy. Tumor endothelial cells (TECs), which line the inner layer of blood vessels of the tumor stromal tissue, are the main targets of anti-angiogenic therapy. Because new tumor blood vessels generally sprout from pre-existing vasculature, they have been considered to be the same as normal blood vessels. However, tumor blood vessels demonstrate a markedly abnormal phenotype that includes several important morphological changes. The degree of angiogenesis is determined by the balance between the angiogenic stimulators and inhibitors released by the tumor and host cells. Recent studies have revealed that TECs also exhibit altered characteristics which depend on the tumor microenvironment. Here, we review recent studies on TEC abnormalities and heterogeneity with respect to tumor progression and consider their therapeutic implications. PMID:26879652

  20. The Impact of Microgravity and Hypergravity on Endothelial Cells

    PubMed Central

    Maier, Jeanette A. M.

    2015-01-01

    The endothelial cells (ECs), which line the inner surface of vessels, play a fundamental role in maintaining vascular integrity and tissue homeostasis, since they regulate local blood flow and other physiological processes. ECs are highly sensitive to mechanical stress, including hypergravity and microgravity. Indeed, they undergo morphological and functional changes in response to alterations of gravity. In particular microgravity leads to changes in the production and expression of vasoactive and inflammatory mediators and adhesion molecules, which mainly result from changes in the remodelling of the cytoskeleton and the distribution of caveolae. These molecular modifications finely control cell survival, proliferation, apoptosis, migration, and angiogenesis. This review summarizes the state of the art on how microgravity and hypergravity affect cultured ECs functions and discusses some controversial issues reported in the literature. PMID:25654101

  1. Focally regulated endothelial proliferation and cell death in human synovium.

    PubMed Central

    Walsh, D. A.; Wade, M.; Mapp, P. I.; Blake, D. R.

    1998-01-01

    Angiogenesis and vascular insufficiency each may support the chronic synovial inflammation of rheumatoid arthritis. We have shown by quantitative immunohistochemistry and terminal uridyl deoxynucleotide nick end labeling that endothelial proliferation and cell death indices were each increased in synovia from patients with rheumatoid arthritis compared with osteoarthritic and noninflamed controls, whereas endothelial fractional areas did not differ significantly among disease groups. Markers of proliferation were associated with foci immunoreactive for vascular endothelial growth factor and integrin alpha(v)beta3, whereas cell death was observed in foci in which immunoreactivities for these factors were weak or absent. No association was found with thrombospondin immunoreactivity. The balance between angiogenesis and vascular regression in rheumatoid synovitis may be determined by the focal expression of angiogenic and endothelial survival factors. Increased endothelial cell turnover may contribute to microvascular dysfunction and thereby facilitate persistent synovitis. Images Figure 1 Figure 3 Figure 4 PMID:9502411

  2. In vivo Endothelial Cell Infection by Anaplasma marginale

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anaplasma marginale has recently been shown to infect endothelial cells in vitro but it remains unknown as to whether endothelial infection also occurs in vivo. In this report, we demonstrate through dual fluorescence microscopy that A. marginale, detected by the monoclonal antibody, ANAF16C1, co-lo...

  3. The role of Hath6, a newly identified shear-stress-responsive transcription factor, in endothelial cell differentiation and function

    PubMed Central

    Fang, Fang; Wasserman, Scott M.; Torres-Vazquez, Jesus; Weinstein, Brant; Cao, Feng; Li, Zongjin; Wilson, Kitchener D.; Yue, Wen; Wu, Joseph C.; Xie, Xiaoyan; Pei, Xuetao

    2014-01-01

    ABSTRACT The key regulators of endothelial differentiation that is induced by shear stress are mostly unclear. Human atonal homolog 6 (Hath6 or ATOH8) is an endothelial-selective and shear-stress-responsive transcription factor. In this study, we sought to elucidate the role of Hath6 in the endothelial specification of embryonic stem cells. In a stepwise human embryonic stem cell to endothelial cell (hESC-EC) induction system, Hath6 mRNA was upregulated synchronously with endothelial determination. Subsequently, gain-of-function and loss-of-function studies of Hath6 were performed using the hESC-EC induction model and endothelial cell lines. The overexpression of Hath6, which mimics shear stress treatment, resulted in an increased CD45−CD31+KDR+ population, a higher tubular-structure-formation capacity and increased endothelial-specific gene expression. By contrast, the knockdown of Hath6 mRNA markedly decreased endothelial differentiation. Hath6 also facilitated the maturation of endothelial cells in terms of endothelial gene expression, tubular-structure formation and cell migration. We further demonstrated that the gene encoding eNOS is a direct target of Hath6 through a reporter system assay and western blot analysis, and that the inhibition of eNOS diminishes hESC-EC differentiation. These results suggest that eNOS plays a key role in linking Hath6 to the endothelial phenotype. Further in situ hybridization studies in zebrafish and mouse embryos indicated that homologs of Hath6 are involved in vasculogenesis and angiogenesis. This study provides the first confirmation of the positive impact of Hath6 on human embryonic endothelial differentiation and function. Moreover, we present a potential signaling pathway through which shear stress stimulates endothelial differentiation. PMID:24463812

  4. The role of Hath6, a newly identified shear-stress-responsive transcription factor, in endothelial cell differentiation and function.

    PubMed

    Fang, Fang; Wasserman, Scott M; Torres-Vazquez, Jesus; Weinstein, Brant; Cao, Feng; Li, Zongjin; Wilson, Kitchener D; Yue, Wen; Wu, Joseph C; Xie, Xiaoyan; Pei, Xuetao

    2014-04-01

    The key regulators of endothelial differentiation that is induced by shear stress are mostly unclear. Human atonal homolog 6 (Hath6 or ATOH8) is an endothelial-selective and shear-stress-responsive transcription factor. In this study, we sought to elucidate the role of Hath6 in the endothelial specification of embryonic stem cells. In a stepwise human embryonic stem cell to endothelial cell (hESC-EC) induction system, Hath6 mRNA was upregulated synchronously with endothelial determination. Subsequently, gain-of-function and loss-of-function studies of Hath6 were performed using the hESC-EC induction model and endothelial cell lines. The overexpression of Hath6, which mimics shear stress treatment, resulted in an increased CD45(-)CD31(+)KDR(+) population, a higher tubular-structure-formation capacity and increased endothelial-specific gene expression. By contrast, the knockdown of Hath6 mRNA markedly decreased endothelial differentiation. Hath6 also facilitated the maturation of endothelial cells in terms of endothelial gene expression, tubular-structure formation and cell migration. We further demonstrated that the gene encoding eNOS is a direct target of Hath6 through a reporter system assay and western blot analysis, and that the inhibition of eNOS diminishes hESC-EC differentiation. These results suggest that eNOS plays a key role in linking Hath6 to the endothelial phenotype. Further in situ hybridization studies in zebrafish and mouse embryos indicated that homologs of Hath6 are involved in vasculogenesis and angiogenesis. This study provides the first confirmation of the positive impact of Hath6 on human embryonic endothelial differentiation and function. Moreover, we present a potential signaling pathway through which shear stress stimulates endothelial differentiation. PMID:24463812

  5. The Novel Methods for Analysis of Exosomes Released from Endothelial Cells and Endothelial Progenitor Cells

    PubMed Central

    Wang, Jinju; Guo, Runmin; Yang, Yi; Jacobs, Bradley; Chen, Suhong; Iwuchukwu, Ifeanyi; Gaines, Kenneth J.; Chen, Yanfang; Simman, Richard; Lv, Guiyuan; Wu, Keng; Bihl, Ji C.

    2016-01-01

    Exosomes (EXs) are cell-derived vesicles that mediate cell-cell communication and could serve as biomarkers. Here we described novel methods for purification and phenotyping of EXs released from endothelial cells (ECs) and endothelial progenitor cells (EPCs) by combining microbeads and fluorescence quantum dots (Q-dots®) techniques. EXs from the culture medium of ECs and EPCs were isolated and detected with cell-specific antibody conjugated microbeads and second antibody conjugated Q-dots by using nanoparticle tracking analysis (NTA) system. The sensitivities of the cell origin markers for ECs (CD105, CD144) and EPCs (CD34, KDR) were evaluated. The sensitivity and specificity were determined by using positive and negative markers for EXs (CD63), platelets (CD41), erythrocytes (CD235a), and microvesicles (Annexin V). Moreover, the methods were further validated in particle-free plasma and patient samples. Results showed that anti-CD105/anti-CD144 and anti-CD34/anti-KDR had the highest sensitivity and specificity for isolating and detecting EC-EXs and EPC-EXs, respectively. The methods had the overall recovery rate of over 70% and were able to detect the dynamical changes of circulating EC-EXs and EPC-EXs in acute ischemic stroke. In conclusion, we have developed sensitive and specific microbeads/Q-dots fluorescence NTA methods for EC-EX and EPC-EX isolation and detection, which will facilitate the functional study and biomarker discovery. PMID:27118976

  6. The natural antioxidants, pomegranate extract and soy isoflavones, favourably modulate canine endothelial cell function.

    PubMed

    Baumgartner-Parzer, Sabina M; Waldenberger, Ferdinand Rudolf; Freudenthaler, Angelika; Ginouvès-Guerdoux, Amandine; McGahie, David; Gatto, Hugues

    2012-01-01

    Cardiovascular disease, preceded by vascular endothelial dysfunction, is a prominent cause of death in dogs. L-carnitine and taurine, well known for their antioxidative capacity, beneficially affect cardiovascular disease as well as certain dog cardiomyopathies. It is well established that vascular endothelial dysfunction precedes cardiovascular disease and that "vasoprotective factors" (NO and antioxidants) prevent apoptosis, whereas "risk factors" such as oxidized LDL, hyperglycemia, and free fatty acids trigger it in cultured human vascular endothelial cells. Whereas human vascular cell in vitro models are widely established and used for the characterisation of potential vasoprotective substances, such models are not available for canine endothelial cells. In the present study we therefore developed an in vitro model, which allows the testing of the effects of different substances on proliferation and apoptosis in canine aortic endothelial cells. This model was used to test L-carnitine, taurine, pomegranate extract, and Soy Isoflavones in comparison to reference substances (glutathione and pioglitazone) previously shown to modulate human endothelial cell function. L-carnitine and taurine neither exhibited antiproliferative nor antiapoptotic activities in the context of this study. However extracts from pomegranate and soy isoflavones dramatically reduced proliferation and apoptosis in a dose dependent fashion, being in line with a vasoprotective activity in dogs. PMID:23762588

  7. Endothelial progenitor cell recruitment in a microfluidic vascular model.

    PubMed

    Lewis, Daniel M; Abaci, Hasan E; Xu, Yu; Gerecht, Sharon

    2015-12-01

    During vessel injury, endothelial progenitors cells (EPCs) are recruited from bone marrow and directed to the hypoxic injury site. The hypoxic conditions in the damaged blood vessel promote TNF-α, which upregulates intercellular adhesion molecule-1 (ICAM-1). EPCs attach to endothelial cell lining using ICAM-1. Here we aimed to examine EPC attachment to ECs in an injured-blood vessel conditions. We first determined ICAM-1 expression in stimulated HUVECs. We stimulated HUVECs with 21% oxygen (atmospheric), atmospheric with TNF-α-supplemented media, 1% oxygen (hypoxia), and hypoxia with TNF-α-supplemented media and found the highest ECFC attachment on HUVECs stimulated with TNF-α and hypoxia, correlating with the highest ICAM-1 expression. We next designed, fabricated and tested a three-dimensional microbioreactor (3D MBR) system with precise control and monitoring of dissolve oxygen and media flow rate in the cellular environment. We utilized a step-wise seeding approach, producing monolayer of HUVECs on all four walls. When stimulated with both TNF-α and hypoxia, ECFC retention on HUVECs was significantly increased under low shear stress compared to static controls. Overall, the 3D MBR system mimics the pathological oxygen tension and shear stress in the damaged vasculature, providing a platform to model vascular-related disorders. PMID:26693599

  8. Endothelial Cell Morphology and Migration are Altered by Changes in Gravitational Fields

    NASA Technical Reports Server (NTRS)

    Melhado, Caroline; Sanford, Gary; Harris-Hooker, Sandra

    1997-01-01

    Endothelial cell migration is important to vascular wall regeneration following injury or stress. However, the mechanism(s) governing this response is not well understood. The microgravity environment of space may complicate the response of these cells to injury. To date, there are no reports in this area. We examined how bovine aortic (BAEC) and pulmonary (BPEC) endothelial cells respond to denudation injury under hypergravity (HGrav) and simulated microgravity (MGrav), using image analysis. In 10% FBS, the migration of confluent BAEC and BPEC into the denuded area was not affected by HGrav or MGrav. However, in low FBS (0.5%), signficantly retarded migration under MGrav, and increased migration under HGrav was found. MGrav also decreased the migration of postconfluent BPEC while HGrav showed no difference. Both MGrav and HGrav strongly decreased the migration of postconfluent BAEC. Also, both cell lines showed significant morphological changes by scanning electron microscopy. These studies indicate that endothelial cell function is affected by changes in gravity.

  9. Endothelial Cells Direct Mesenchymal Stem Cells Toward a Smooth Muscle Cell Fate

    PubMed Central

    Lin, Cho-Hao

    2014-01-01

    Under defined conditions, mesenchymal stem cells can differentiate into unique cell types, making them attractive candidates for cell-based disease therapies. Ischemic diseases would greatly benefit from treatments that include the formation of new blood vessels from mesenchymal stem cells. However, blood vessels are complex structures composed of endothelial cells and smooth muscle cells, and their assembly and function in a diseased environment is reliant upon joining with the pre-existing vasculature. Although endothelial cell/smooth muscle cell interactions are well known, how endothelial cells may influence mesenchymal stem cells and facilitate their differentiation has not been defined. Therefore, we sought to explore how endothelial cells might drive mesenchymal stem cells toward a smooth muscle fate. Our data show that cocultured endothelial cells induce smooth muscle cell differentiation in mesenchymal stem cells. Endothelial cells can promote a contractile phenotype, reduce proliferation, and enhance collagen synthesis and secretion. Our data show that Notch signaling is essential for endothelial cell-dependent differentiation, and this differentiation pathway is largely independent of growth factor signaling mechanisms. PMID:24914692

  10. SNEV overexpression extends the life span of human endothelial cells

    SciTech Connect

    Voglauer, Regina; Chang, Martina Wei-Fen; Dampier, Brigitta; Wieser, Matthias; Baumann, Kristin; Sterovsky, Thomas; Schreiber, Martin; Katinger, Hermann; Grillari, Johannes . E-mail: j.grillari@iam.boku.ac.at

    2006-04-01

    In a recent screening for genes downregulated in replicatively senescent human umbilical vein endothelial cells (HUVECs), we have isolated the novel protein SNEV. Since then SNEV has proven as a multifaceted protein playing a role in pre-mRNA splicing, DNA repair, and the ubiquitin/proteosome system. Here, we report that SNEV mRNA decreases in various cell types during replicative senescence, and that it is increased in various immortalized cell lines, as well as in breast tumors, where SNEV transcript levels also correlate with the survival of breast cancer patients. Since these mRNA profiles suggested a role of SNEV in the regulation of cell proliferation, the effect of its overexpression was tested. Thereby, a significant extension of the cellular life span was observed, which was not caused by altered telomerase activity or telomere dynamics but rather by enhanced stress resistance. When SNEV overexpressing cells were treated with bleomycin or bleomycin combined with BSO, inducing DNA damage as well as reactive oxygen species, a significantly lower fraction of apoptotic cells was found in comparison to vector control cells. These data suggest that high levels of SNEV might extend the cellular life span by increasing the resistance to stress or by improving the DNA repair capacity of the cells.

  11. Nitric oxide modulates lipopolysaccharide-induced endothelial platelet endothelial cell adhesion molecule expression via interleukin-10.

    PubMed

    Hebeda, C B; Teixeira, S A; Tamura, E K; Muscará, M N; de Mello, S B V; Markus, R P; Farsky, S H P

    2011-08-01

    We have shown previously that nitric oxide (NO) controls platelet endothelial cell adhesion molecule (PECAM-1) expression on both neutrophils and endothelial cells under physiological conditions. Here, the molecular mechanism by which NO regulates lipopolysaccharide (LPS)-induced endothelial PECAM-1 expression and the role of interleukin (IL)-10 on this control was investigated. For this purpose, N-(G)-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg/day for 14 days dissolved in drinking water) was used to inhibit both constitutive (cNOS) and inducible nitric oxide (iNOS) synthase activities in LPS-stimulated Wistar rats (5 mg/kg, intraperitoneally). This treatment resulted in reduced levels of serum NO. Under this condition, circulating levels of IL-10 was enhanced, secreted mainly by circulating lymphocytes, dependent on transcriptional activation, and endothelial PECAM-1 expression was reduced independently on reduced gene synthesis. The connection between NO, IL-10 and PECAM-1 expression was examined by incubating LPS-stimulated (1 µg/ml) cultured endothelial cells obtained from naive rats with supernatant of LPS-stimulated lymphocytes, which were obtained from blood of control or L-NAME-treated rats. Supernatant of LPS-stimulated lymphocytes obtained from L-NAME-treated rats, which contained higher levels of IL-10, reduced LPS-induced PECAM-1 expression by endothelial cells, and this reduction was reversed by adding the anti-IL-10 monoclonal antibody. Therefore, an association between NO, IL-10 and PECAM-1 was found and may represent a novel mechanism by which NO controls endothelial cell functions. PMID:21564091

  12. Blasted Cell Line Names

    PubMed Central

    Wang, Jing; Byers, Lauren A.; Yordy, John S.; Liu, Wenbin; Shen, Li; Baggerly, Keith A.; Giri, Uma; Myers, Jeffrey N.; Ang, K. Kian; Story, Michael D.; Girard, Luc; Minna, John D.; Heymach, John V.; Coombes, Kevin R.

    2010-01-01

    Background: While trying to integrate multiple data sets collected by different researchers, we noticed that the sample names were frequently entered inconsistently. Most of the variations appeared to involve punctuation, white space, or their absence, at the juncture between alphabetic and numeric portions of the cell line name. Results: Reasoning that the variant names could be described in terms of mutations or deletions of character strings, we implemented a simple version of the Needleman-Wunsch global sequence alignment algorithm and applied it to the cell line names. All correct matches were found by this procedure. Incorrect matches only occured when a cell line was present in one data set but not in the other. The raw match scores tended to be substantially worse for the incorrect matches. Conclusions: A simple application of the Needleman-Wunsch global sequence alignment algorithm provides a useful first pass at matching sample names from different data sets. PMID:21082038

  13. Endothelial cell transfusion ameliorates endothelial dysfunction in 5/6 nephrectomized rats

    PubMed Central

    Pacurari, Maricica; Xing, Dongqi; Hilgers, Rob H. P.; Guo, Yuan Yuan; Yang, Zhengqin

    2013-01-01

    Endothelial dysfunction is prevalent in chronic kidney disease. This study tested the hypothesis that transfusion of rat aortic endothelial cells (ECs) ameliorates endothelial dysfunction in a rat model of chronic kidney disease. Male Sprague-Dawley rats underwent sham surgery or 5/6 nephrectomy (Nx). Five weeks after Nx, EC (1.5 × 106 cells/rat) or vehicle were transfused intravenously. One week later, vascular reactivity of mesenteric artery was assessed on a wire myograph. Sensitivity of endothelium-dependent relaxation to acetylcholine and maximum vasodilation were impaired by Nx and improved by EC transfusion. Using selective pharmacological nitric oxide synthase isoform inhibitors, we demonstrated that the negative effect of Nx on endothelial function and rescue by EC transfusion are, at least in part, endothelial nitric oxide synthase mediated. Plasma asymmetric dimethylarginine was increased by Nx and decreased by EC transfusion, whereas mRNA expression of dimethylarginine dimethylaminohydrolases 1 (DDAH1) was decreased by Nx and restored by EC transfusion. Immunohistochemical staining confirmed that local expression of DDAH1 is decreased by Nx and increased by EC transfusion. In conclusion, EC transfusion attenuates Nx-induced endothelium-dependent vascular dysfunction by regulating DDAH1 expression and enhancing endothelial nitric oxide synthase activity. These results suggest that EC-based therapy could provide a novel therapeutic strategy to improve vascular function in chronic kidney disease. PMID:23955716

  14. Endothelial cell–cell adhesion during zebrafish vascular development

    PubMed Central

    Lagendijk, Anne Karine; Yap, Alpha S; Hogan, Benjamin M

    2014-01-01

    The vertebrate vasculature is an essential organ network with major roles in health and disease. The establishment of balanced cell–cell adhesion in the endothelium is crucial for the functionality of the vascular system. Furthermore, the correct patterning and integration of vascular endothelial cell–cell adhesion drives the morphogenesis of new vessels, and is thought to couple physical forces with signaling outcomes during development. Here, we review insights into this process that have come from studies in zebrafish. First, we describe mutants in which endothelial adhesion is perturbed, second we describe recent progress using in vivo cell biological approaches that allow the visualization of endothelial cell–cell junctions. These studies underline the profound potential of this model system to dissect in great detail the function of both known and novel regulators of endothelial cell–cell adhesion. PMID:24621476

  15. Endothelial cell markers reflecting endothelial cell dysfunction in patients with mixed connective tissue disease

    PubMed Central

    2010-01-01

    Introduction The aim of the present study was to investigate the association between cardiovascular risk factors and endothelial dysfunction in patients with mixed connective tissue disease (MCTD) and to determine which biomarkers are associated with atherosclerotic complications, such as cardiovascular disease. Methods Fifty MCTD patients and 38 healthy age-matched and sex-matched controls were enrolled in this study. In order to describe endothelial dysfunction, we assessed flow-mediated dilation (FMD), nitrate-mediated dilation (NMD) and carotid artery intima-media thickness (IMT). We investigated FMD of the brachial artery after reactive hyperemia and NMD after sublingual nitroglycerin administration, while the IMT of the common carotid artery was determined by ultrasound. Anti-U1 ribonucleoprotein (anti-U1RNP) antibodies, anti-cardiolipin (anti-CL) antibodies, anti-endothelial cell antibody (AECA) and endothelial cell markers, such as soluble thrombomodulin (TM) and von Willebrand factor antigen (vWFAg), were assessed. Results The endothelium-dependent vasodilation (FMD) was significantly impaired in patients with MCTD, as compared with controls (%FMD: 4.7 ± 4.2% vs. 8.7 ± 5.0%; P < 0.001), while the percentage NMD did not differ (%NMD: 14.3 ± 6.6% vs. 17.1 ± 6.7%; P = 0.073). Mean carotid IMT values were higher in patients than in controls (IMT: MCTD, 0.64 ± 0.13 mm vs. controls, 0.53 ± 0.14 mm; P < 0.001). FMD negatively correlated with disease duration, the levels of apolipoprotein A1, the paraoxonase-1 activity, and systolic blood pressure in MCTD patients. The percentage FMD was significantly lower in MCTD patients with cardiovascular diseases (CVD), than in those without CVD (%FMD: 3.5 ± 2.9 vs. 5.8 ± 4.8, P < 0.0002), while percentage NMD did not differ between patients with and without CVDs. Serum levels of autoantibodies (anti-U1RNP, AECA and anti-CL) were significantly higher in MCTD patients and differed between MCTD patients with and

  16. Substrates for Expansion of Corneal Endothelial Cells towards Bioengineering of Human Corneal Endothelium

    PubMed Central

    Navaratnam, Jesintha; Utheim, Tor P.; Rajasekhar, Vinagolu K.; Shahdadfar, Aboulghassem

    2015-01-01

    Corneal endothelium is a single layer of specialized cells that lines the posterior surface of cornea and maintains corneal hydration and corneal transparency essential for vision. Currently, transplantation is the only therapeutic option for diseases affecting the corneal endothelium. Transplantation of corneal endothelium, called endothelial keratoplasty, is widely used for corneal endothelial diseases. However, corneal transplantation is limited by global donor shortage. Therefore, there is a need to overcome the deficiency of sufficient donor corneal tissue. New approaches are being explored to engineer corneal tissues such that sufficient amount of corneal endothelium becomes available to offset the present shortage of functional cornea. Although human corneal endothelial cells have limited proliferative capacity in vivo, several laboratories have been successful in in vitro expansion of human corneal endothelial cells. Here we provide a comprehensive analysis of different substrates employed for in vitro cultivation of human corneal endothelial cells. Advances and emerging challenges with ex vivo cultured corneal endothelial layer for the ultimate goal of therapeutic replacement of dysfunctional corneal endothelium in humans with functional corneal endothelium are also presented. PMID:26378588

  17. Hypertension alters phosphorylation of VASP in brain endothelial cells.

    PubMed

    Arlier, Zulfikar; Basar, Murat; Kocamaz, Erdogan; Kiraz, Kemal; Tanriover, Gamze; Kocer, Gunnur; Arlier, Sefa; Giray, Semih; Nasırcılar, Seher; Gunduz, Filiz; Senturk, Umit K; Demir, Necdet

    2015-04-01

    Hypertension impairs cerebral vascular function. Vasodilator-stimulated phosphoprotein (VASP) mediates active reorganization of the cytoskeleton via membrane ruffling, aggregation and tethering of actin filaments. VASP regulation of endothelial barrier function has been demonstrated by studies using VASP(-/-) animals under conditions associated with tissue hypoxia. We hypothesize that hypertension regulates VASP expression and/or phosphorylation in endothelial cells, thereby contributing to dysfunction in the cerebral vasculature. Because exercise has direct and indirect salutary effects on vascular systems that have been damaged by hypertension, we also investigated the effect of exercise on maintenance of VASP expression and/or phosphorylation. We used immunohistochemistry, Western blotting and immunocytochemistry to examine the effect of hypertension on VASP expression and phosphorylation in brain endothelial cells in normotensive [Wistar-Kyoto (WKY)] and spontaneously hypertensive (SH) rats under normal and exercise conditions. In addition, we analyzed VASP regulation in normoxia- and hypoxia-induced endothelial cells. Brain endothelial cells exhibited significantly lower VASP immunoreactivity and phosphorylation at the Ser157 residue in SHR versus WKY rats. Exercise reversed hypertension-induced alterations in VASP phosphorylation. Western blotting and immunocytochemistry indicated reduction in VASP phosphorylation in hypoxic versus normoxic endothelial cells. These results suggest that diminished VASP expression and/or Ser157 phosphorylation mediates endothelial changes associated with hypertension and exercise may normalize these changes, at least in part, by restoring VASP phosphorylation. PMID:24894047

  18. Expression of cell-cell and cell-matrix adhesion proteins by sinusoidal endothelial cells in the normal and cirrhotic human liver.

    PubMed Central

    Couvelard, A.; Scoazec, J. Y.; Feldmann, G.

    1993-01-01

    We compared the expression of cell-cell and cell-matrix adhesion proteins by sinusoidal endothelial cells in normal human liver, in which the endothelial lining of hepatic sinusoids is discontinuous and devoid of basement membrane, and in cirrhosis, during which sinusoids might undergo a process of capillarization and acquire a continuous lining and a typical basement membrane. In normal liver, sinusoidal endothelial cells displayed a very restricted repertory of cell-adhesion molecules: the intercellular adhesion molecules PECAM-1 and CD34 were undetectable and only two integrins, alpha 1 beta 1 and alpha 5 beta 1, were present, whereas the laminin receptors alpha 6 beta 1 and alpha 2 beta 1 were undetectable and the beta 3 integrins were faintly expressed. In capillarized sinusoids, sinusoidal endothelial cells displayed striking changes in their repertory of cell-adhesion molecules, including the expression of PECAM-1 protein and messenger RNAs and the induction of the laminin receptors alpha 6 beta 1 and alpha 2 beta 1. Such changes co-localized with subendothelial laminin deposits. In conclusion, normal sinusoidal endothelial cells express a distinctive set of cell-adhesion molecules, adapted to their structural and microenvironmental characteristics, and this repertory is dramatically modified during sinusoidal capillarization, possibly as a consequence of the concomitant matrix changes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8362973

  19. Induction of connective tissue growth factor (CTGF) in human endothelial cells by lysophosphatidic acid, sphingosine-1-phosphate, and platelets.

    PubMed

    Muehlich, Susanne; Schneider, Nadine; Hinkmann, Fabian; Garlichs, Christoph D; Goppelt-Struebe, Margarete

    2004-08-01

    Endothelial dysfunction is characterized by multiple interactions between endothelial cells and components of the blood. This study focussed on the induction of the pro-atherogenic connective tissue growth factor (CTGF) in endothelial cells by bioactive lipids and platelets. Lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) led to a time- and concentration-dependent increase in CTGF mRNA and protein expression in the human endothelial cell line EAHY 926 and in primary cultures of human umbilical vein endothelial cells (HUVEC). As both cell types expressed various receptors for LPA and S1P, signaling pathways were further characterized by pharmacological means: induction of CTGF was pertussis toxin-insensitive and inhibition of activation of p42/44 MAP kinases only partially reduced CTGF expression. On the contrary, interference with the RhoA signaling pathway by simvastatin, an inhibitor of geranylgeranyltransferases, or the Rho-kinase inhibitor Y27632 prevented induction of CTGF. Co-incubation of endothelial cells with freshly isolated human platelets significantly increased the expression of CTGF mRNA in endothelial cells, which was also sensitive to simvastatin. Up-regulation of CTGF in endothelial cells, induced by LPA, S1P, or platelets, may contribute to the initiation and progression of atherosclerosis. Interference of simvastatin with the synthesis of this pro-atherogenic factor further supports the anti-atherogenic role of statins. PMID:15262182

  20. Tumour Angiogenesis: Ultrastructure of Endothelial Cells in Mitosis

    PubMed Central

    Warren, B. A.; Greenblatt, M.; Kommineni, V. R. C.

    1972-01-01

    Under the influence of a diffusible factor or factors from melanoma tumour tissue and neonatal hamster renal tissue, which passed through millipore filters, the endothelial cells of capillaries and small venules in the adult hamster were found to undergo mitotic division. Occasional endothelial cells in mitosis were noted in small arteries. Endothelial cells within the same vessel did not undergo mitosis in a synchronous fashion. During mitosis they retained intact their intercellular junctions with adjacent endothelial cells. No specific orientation of the mitotic spindle to the long axis of the vessel was noted. The usual appearance of cells in division was observed in this specific instance of endothelial cells in an adult animal undergoing mitotic division. In particular the formation of chromosomes and the various changes that ensue in the nuclear membrane were traced within endothelial cells. Typical spindle lamellae were found in cells during the formation of the membranes of the daughter nuclei. ImagesFig. 7Fig. 1Figs. 2-3Figs. 4-5Fig. 6 PMID:4555714

  1. High-density lipoprotein endocytosis in endothelial cells

    PubMed Central

    Fruhwürth, Stefanie; Pavelka, Margit; Bittman, Robert; Kovacs, Werner J; Walter, Katharina M; Röhrl, Clemens; Stangl, Herbert

    2013-01-01

    AIM: To describe the way stations of high-density lipoprotein (HDL) uptake and its lipid exchange in endothelial cells in vitro and in vivo. METHODS: A combination of fluorescence microscopy using novel fluorescent cholesterol surrogates and electron microscopy was used to analyze HDL endocytosis in great detail in primary human endothelial cells. Further, HDL uptake was quantified using radio-labeled HDL particles. To validate the in vitro findings mice were injected with fluorescently labeled HDL and particle uptake in the liver was analyzed using fluorescence microscopy. RESULTS: HDL uptake occurred via clathrin-coated pits, tubular endosomes and multivesicular bodies in human umbilical vein endothelial cells. During uptake and resecretion, HDL-derived cholesterol was exchanged at a faster rate than cholesteryl oleate, resembling the HDL particle pathway seen in hepatic cells. In addition, lysosomes were not involved in this process and thus HDL degradation was not detectable. In vivo, we found HDL mainly localized in mouse hepatic endothelial cells. HDL was not detected in parenchymal liver cells, indicating that lipid transfer from HDL to hepatocytes occurs primarily via scavenger receptor, class B, type I mediated selective uptake without concomitant HDL endocytosis. CONCLUSION: HDL endocytosis occurs via clathrin-coated pits, tubular endosomes and multivesicular bodies in human endothelial cells. Mouse endothelial cells showed a similar HDL uptake pattern in vivo indicating that the endothelium is one major site of HDL endocytosis and transcytosis. PMID:24340136

  2. Activation of Endothelial Nitric Oxide (eNOS) Occurs through Different Membrane Domains in Endothelial Cells

    PubMed Central

    Tran, Jason; Magenau, Astrid; Rodriguez, Macarena; Rentero, Carles; Royo, Teresa; Enrich, Carlos; Thomas, Shane R.; Grewal, Thomas; Gaus, Katharina

    2016-01-01

    Endothelial cells respond to a large range of stimuli including circulating lipoproteins, growth factors and changes in haemodynamic mechanical forces to regulate the activity of endothelial nitric oxide synthase (eNOS) and maintain blood pressure. While many signalling pathways have been mapped, the identities of membrane domains through which these signals are transmitted are less well characterized. Here, we manipulated bovine aortic endothelial cells (BAEC) with cholesterol and the oxysterol 7-ketocholesterol (7KC). Using a range of microscopy techniques including confocal, 2-photon, super-resolution and electron microscopy, we found that sterol enrichment had differential effects on eNOS and caveolin-1 (Cav1) colocalisation, membrane order of the plasma membrane, caveolae numbers and Cav1 clustering. We found a correlation between cholesterol-induced condensation of the plasma membrane and enhanced high density lipoprotein (HDL)-induced eNOS activity and phosphorylation suggesting that cholesterol domains, but not individual caveolae, mediate HDL stimulation of eNOS. Vascular endothelial growth factor (VEGF)-induced and shear stress-induced eNOS activity was relatively independent of membrane order and may be predominantly controlled by the number of caveolae on the cell surface. Taken together, our data suggest that signals that activate and phosphorylate eNOS are transmitted through distinct membrane domains in endothelial cells. PMID:26977592

  3. The use of novel lymphatic endothelial cell-specific immunohistochemical markers to differentiate cutaneous angiosarcomas in dogs.

    PubMed

    Halsey, C H C; Worley, D R; Curran, K; Charles, J B; Ehrhart, E J

    2016-09-01

    Lymphangiosarcomas are uncommon vascular neoplasms that arise from lymphatic endothelial cells (LECs). They efface and replace normal subcutaneous tissue and are characterised by arborising, vascular channels lined by a single layer of pleomorphic endothelial cells and a paucity of erythrocytes. Lymphangiosarcomas are architecturally similar to hemangiosarcomas, a common malignancy of vascular origin arising from blood vascular endothelial cells. Common immunohistochemical markers for vascular endothelium, such as Factor VIII-related antigen (F8RA) and CD31, have traditionally been used to confirm the diagnosis of tumours of vascular origin. However, these markers fail to differentiate between lymphangiosarcoma and hemangiosarcoma, which often show overlapping morphologic features, disparate clinical behaviour and require different treatment modalities. Here we describe the use of two novel LEC-specific markers, lymphatic vessel endothelial receptor-1 (LYVE-1) and prospero-related homeobox gene-1 (PROX-1), to further differentiate between vascular tumours of lymphatic (lymphangiosarcoma) and blood (hemangiosarcoma) endothelial cell origin in the dog. PMID:24593773

  4. Oxidized-LDL induce the expression of heat shock protein 70 in human endothelial cells.

    PubMed

    Zhu, W; Roma, P; Pellegatta, F; Catapano, A L

    1994-04-15

    Heat shock proteins are detectable in human atherosclerotic plaques, especially in endothelial cells. In this report we show by immunofluorescence that incubation "in vitro" with OxLDL is a stress capable of inducing the expression of heat shock protein 70 in both the EAhy-926 cell line and human umbilical vein endothelial cells (HUVEC). This induction was parallel to the cytotoxicity of oxidized LDL as determined by [3H]adenine release. When cells were confluent, however, both effects were greatly reduced. We speculate that induction of hsp70 is related to the cytotoxicity of oxidized LDL and that the detection of heat shock proteins in human atherosclerotic plaques is a further indication for the presence "in vivo" of oxidized LDL. These observations may be relevant to the understanding of endothelial response to injury in proatherosclerotic events. PMID:8166710

  5. Tipping off endothelial tubes: nitric oxide drives tip cells.

    PubMed

    Priya, Mani Krishna; Sahu, Giriraj; Soto-Pantoja, David R; Goldy, Naga; Sundaresan, Abaya Meenakshi; Jadhav, Vivek; Barathkumar, T R; Saran, Uttara; Jaffar Ali, B M; Roberts, David D; Bera, Amal Kanti; Chatterjee, Suvro

    2015-04-01

    Angiogenesis, the formation of new blood vessels from pre-existing vessels, is a complex process that warrants cell migration, proliferation, tip cell formation, ring formation, and finally tube formation. Angiogenesis is initiated by a single leader endothelial cell called "tip cell," followed by vessel elongation by "stalk cells." Tip cells are characterized by their long filopodial extensions and expression of vascular endothelial growth factor receptor-2 and endocan. Although nitric oxide (NO) is an important modulator of angiogenesis, its role in angiogenic sprouting and specifically in tip cell formation is poorly understood. The present study tested the role of endothelial nitric oxide synthase (eNOS)/NO/cyclic GMP (cGMP) signaling in tip cell formation. In primary endothelial cell culture, about 40% of the tip cells showed characteristic sub-cellular localization of eNOS toward the anterior progressive end of the tip cells, and eNOS became phosphorylated at serine 1177. Loss of eNOS suppressed tip cell formation. Live cell NO imaging demonstrated approximately 35% more NO in tip cells compared with stalk cells. Tip cells showed increased level of cGMP relative to stalk cells. Further, the dissection of NO downstream signaling using pharmacological inhibitors and inducers indicates that NO uses the sGC/cGMP pathway in tip cells to lead angiogenesis. Taken together, the present study confirms that eNOS/NO/cGMP signaling defines the direction of tip cell migration and thereby initiates new blood vessel formation. PMID:25510468

  6. Platelet endothelial cell adhesion molecule-1 modulates endothelial cell motility through the small G-protein Rho.

    PubMed

    Gratzinger, Dita; Canosa, Sandra; Engelhardt, Britta; Madri, Joseph A

    2003-08-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1), an immunoglobulin family vascular adhesion molecule, is involved in endothelial cell migration and angiogenesis (1, 2). We found that endothelial cells lacking PECAM-1 exhibit increased single cell motility and extension formation but poor wound healing migration, reminiscent of cells in which Rho activity has been suppressed by overexpressing a GTPase-activating protein (3). The ability of PECAM-1 to restore wound healing migration to PECAM-1-deficient cells was independent of its extracellular domain or signaling via its immunoreceptor tyrosine-based inhibitory motif. PECAM-1-deficient endothelial cells had a selective defect in RhoGTP loading, and inhibition of Rho activity mimicked the PECAM-1-deficient phenotype of increased chemokinetic single cell motility at the expense of coordinated wound healing migration. The wound healing advantage of PECAM-1-positive endothelial cells was not only Rho mediated but pertussis toxin inhibitable, characteristic of migration mediated by heterotrimeric G-protein-linked seven-transmembrane receptor signaling such as signaling in response to the serum sphingolipid sphingosine-1-phosphate (S1P) (4, 5). Indeed, we found that the wound healing defect of PECAM-1 null endothelial cells is minimized in sphingolipid-depleted media; moreover, PECAM-1 null endothelial cells fail to increase their migration in response to S1P. We have also found that PECAM-1 localizes to rafts and that in its absence heterotrimeric G-protein components are differentially recruited to rafts, providing a potential mechanism for PECAM-1-mediated coordination of S1P signaling. PECAM-1 may thus support the effective S1P/RhoGTP signaling required for wound healing endothelial migration by allowing for the spatially directed, coordinated activation of Galpha signaling pathways. PMID:12890700

  7. Alk1 controls arterial endothelial cell migration in lumenized vessels.

    PubMed

    Rochon, Elizabeth R; Menon, Prahlad G; Roman, Beth L

    2016-07-15

    Heterozygous loss of the arterial-specific TGFβ type I receptor, activin receptor-like kinase 1 (ALK1; ACVRL1), causes hereditary hemorrhagic telangiectasia (HHT). HHT is characterized by development of fragile, direct connections between arteries and veins, or arteriovenous malformations (AVMs). However, how decreased ALK1 signaling leads to AVMs is unknown. To understand the cellular mis-steps that cause AVMs, we assessed endothelial cell behavior in alk1-deficient zebrafish embryos, which develop cranial AVMs. Our data demonstrate that alk1 loss has no effect on arterial endothelial cell proliferation but alters arterial endothelial cell migration within lumenized vessels. In wild-type embryos, alk1-positive cranial arterial endothelial cells generally migrate towards the heart, against the direction of blood flow, with some cells incorporating into endocardium. In alk1-deficient embryos, migration against flow is dampened and migration in the direction of flow is enhanced. Altered migration results in decreased endothelial cell number in arterial segments proximal to the heart and increased endothelial cell number in arterial segments distal to the heart. We speculate that the consequent increase in distal arterial caliber and hemodynamic load precipitates the flow-dependent development of downstream AVMs. PMID:27287800

  8. Tumor-derived circulating endothelial cell clusters in colorectal cancer.

    PubMed

    Cima, Igor; Kong, Say Li; Sengupta, Debarka; Tan, Iain B; Phyo, Wai Min; Lee, Daniel; Hu, Min; Iliescu, Ciprian; Alexander, Irina; Goh, Wei Lin; Rahmani, Mehran; Suhaimi, Nur-Afidah Mohamed; Vo, Jess H; Tai, Joyce A; Tan, Joanna H; Chua, Clarinda; Ten, Rachel; Lim, Wan Jun; Chew, Min Hoe; Hauser, Charlotte A E; van Dam, Rob M; Lim, Wei-Yen; Prabhakar, Shyam; Lim, Bing; Koh, Poh Koon; Robson, Paul; Ying, Jackie Y; Hillmer, Axel M; Tan, Min-Han

    2016-06-29

    Clusters of tumor cells are often observed in the blood of cancer patients. These structures have been described as malignant entities for more than 50 years, although their comprehensive characterization is lacking. Contrary to current consensus, we demonstrate that a discrete population of circulating cell clusters isolated from the blood of colorectal cancer patients are not cancerous but consist of tumor-derived endothelial cells. These clusters express both epithelial and mesenchymal markers, consistent with previous reports on circulating tumor cell (CTC) phenotyping. However, unlike CTCs, they do not mirror the genetic variations of matched tumors. Transcriptomic analysis of single clusters revealed that these structures exhibit an endothelial phenotype and can be traced back to the tumor endothelium. Further results show that tumor-derived endothelial clusters do not form by coagulation or by outgrowth of single circulating endothelial cells, supporting a direct release of clusters from the tumor vasculature. The isolation and enumeration of these benign clusters distinguished healthy volunteers from treatment-naïve as well as pathological early-stage (≤IIA) colorectal cancer patients with high accuracy, suggesting that tumor-derived circulating endothelial cell clusters could be used as a means of noninvasive screening for colorectal cancer. In contrast to CTCs, tumor-derived endothelial cell clusters may also provide important information about the underlying tumor vasculature at the time of diagnosis, during treatment, and throughout the course of the disease. PMID:27358499

  9. Cellular and molecular biology of aging endothelial cells.

    PubMed

    Donato, Anthony J; Morgan, R Garrett; Walker, Ashley E; Lesniewski, Lisa A

    2015-12-01

    Cardiovascular disease (CVD) is the leading cause of death in the United States and aging is a major risk factor for CVD development. One of the major age-related arterial phenotypes thought to be responsible for the development of CVD in older adults is endothelial dysfunction. Endothelial function is modulated by traditional CVD risk factors in young adults, but advancing age is independently associated with the development of vascular endothelial dysfunction. This endothelial dysfunction results from a reduction in nitric oxide bioavailability downstream of endothelial oxidative stress and inflammation that can be further modulated by traditional CVD risk factors in older adults. Greater endothelial oxidative stress with aging is a result of augmented production from the intracellular enzymes NADPH oxidase and uncoupled eNOS, as well as from mitochondrial respiration in the absence of appropriate increases in antioxidant defenses as regulated by relevant transcription factors, such as FOXO. Interestingly, it appears that NFkB, a critical inflammatory transcription factor, is sensitive to this age-related endothelial redox change and its activation induces transcription of pro-inflammatory cytokines that can further suppress endothelial function, thus creating a vicious feed-forward cycle. This review will discuss the two macro-mechanistic processes, oxidative stress and inflammation, that contribute to endothelial dysfunction with advancing age as well as the cellular and molecular events that lead to the vicious cycle of inflammation and oxidative stress in the aged endothelium. Other potential mediators of this pro-inflammatory endothelial phenotype are increases in immune or senescent cells in the vasculature. Of note, genomic instability, telomere dysfunction or DNA damage has been shown to trigger cell senescence via the p53/p21 pathway and result in increased inflammatory signaling in arteries from older adults. This review will discuss the current state

  10. Paradoxic effects of metformin on endothelial cells and angiogenesis.

    PubMed

    Dallaglio, Katiuscia; Bruno, Antonino; Cantelmo, Anna R; Esposito, Alessia I; Ruggiero, Luca; Orecchioni, Stefania; Calleri, Angelica; Bertolini, Francesco; Pfeffer, Ulrich; Noonan, Douglas M; Albini, Adriana

    2014-05-01

    The biguanide metformin is used in type 2 diabetes management and has gained significant attention as a potential cancer preventive agent. Angioprevention represents a mechanism of chemoprevention, yet conflicting data concerning the antiangiogenic action of metformin have emerged. Here, we clarify some of the contradictory effects of metformin on endothelial cells and angiogenesis, using in vitro and in vivo assays combined with transcriptomic and protein array approaches. Metformin inhibits formation of capillary-like networks by endothelial cells; this effect is partially dependent on the energy sensor adenosine-monophosphate-activated protein kinase (AMPK) as shown by small interfering RNA knockdown. Gene expression profiling of human umbilical vein endothelial cells revealed a paradoxical modulation of several angiogenesis-associated genes and proteins by metformin, with short-term induction of vascular endothelial growth factor (VEGF), cyclooxygenase 2 and CXC chemokine receptor 4 at the messenger RNA level and downregulation of ADAMTS1. Antibody array analysis shows an essentially opposite regulation of numerous angiogenesis-associated proteins in endothelial and breast cancer cells including interleukin-8, angiogenin and TIMP-1, as well as selective regulation of angiopioetin-1, -2, endoglin and others. Endothelial cell production of the cytochrome P450 member CYP1B1 is upregulated by tumor cell supernatants in an AMPK-dependent manner, metformin blocks this effect. Metformin inhibits VEGF-dependent activation of extracellular signal-regulated kinase 1/2, and the inhibition of AMPK activity abrogates this event. Metformin hinders angiogenesis in matrigel pellets in vivo, prevents the microvessel density increase observed in obese mice on a high-fat diet, downregulating the number of white adipose tissue endothelial precursor cells. Our data show that metformin has an antiangiogenic activity in vitro and in vivo associated with a contradictory short

  11. Expression, Regulation and Function of Atypical Chemerin Receptor CCRL2 on Endothelial Cells

    PubMed Central

    Monnier, Justin; Lewén, Susanna; O’Hara, Edward; Huang, Kexin; Tu, Hua; Butcher, Eugene C; Zabel, Brian A.

    2012-01-01

    CC-chemokine receptor-like 2 (CCRL2) binds leukocyte chemoattractant chemerin and can regulate local levels of the attractant, but does not itself support cell migration. Here we show that CCRL2 and vascular cell adhesion molecule-1 (VCAM-1) are upregulated on cultured human and mouse vascular endothelial cells (EC) and cell lines by pro-inflammatory stimuli. CCRL2 induction is dependent on NF-κB and JAK/STAT signaling pathways, and activated endothelial cells specifically bind chemerin. In vivo, CCRL2 is constitutively expressed at high levels by lung endothelial cells and at lower levels by liver endothelium; and liver but not lung EC respond to systemic LPS injection by further upregulation of the receptor. Plasma levels of total chemerin are elevated in CCRL2−/− mice, and are significantly enhanced after systemic LPS treatment in CCRL2−/− mice compared to WT. Following acute LPS-induced pulmonary inflammation in vivo, CMKLR1+ NK cell recruitment to the airways is significantly impaired in CCRL2−/− mice compared to WT. In vitro, chemerin binding to CCRL2 on endothelial cells triggers robust adhesion of chemokine-like receptor-1 (CMKLR1)-positive lymphoid cells through an α4β1/VCAM-1-dependent mechanism. In conclusion CCRL2 is expressed by endothelial cells in a tissue and activation-dependent fashion; regulates circulating chemerin levels and its bioactivity; and enhances chemerin and CMKLR1-dependent lymphocyte-endothelial cell adhesion in vitro and recruitment to inflamed airways in vivo. Its expression and/or induction on EC by proinflammatory stimuli provide a novel and specific mechanism for the local enrichment of chemerin at inflammatory sites, regulating the recruitment of CMKLR1+ cells. PMID:22696441

  12. Redox Regulation of Endothelial Cell Fate

    PubMed Central

    Song, Ping; Zou, Ming-Hui

    2014-01-01

    Endothelial cells (ECs) are present throughout blood vessels and have variable roles in both physiological and pathological settings. EC fate is altered and regulated by several key factors in physiological or pathological conditions. Reactive nitrogen species and reactive oxygen species derived from NAD(P)H oxidases, mitochondria, or nitric oxide-producing enzymes are not only cytotoxic but also compose a signaling network in the redox system. The formation, actions, key molecular interactions, and physiological and pathological relevance of redox signals in ECs remain unclear. We review the identities, sources, and biological actions of oxidants and reductants produced during EC function or dysfunction. Further, we discuss how ECs shape key redox sensors and examine the biological functions, transcriptional responses, and post-translational modifications evoked by the redox system in ECs. We summarize recent findings regarding the mechanisms by which redox signals regulate the fate of ECs and address the outcome of altered EC fate in health and disease. Future studies will examine if the redox biology of ECs can be targeted in pathophysiological conditions. PMID:24633153

  13. Induction of hematopoietic and endothelial cell program orchestrated by ETS transcription factor ER71/ETV2

    PubMed Central

    Liu, Fang; Li, Daofeng; Yu, Yik Yeung Lawrence; Kang, Inyoung; Cha, Min-Ji; Kim, Ju Young; Park, Changwon; Watson, Dennis K; Wang, Ting; Choi, Kyunghee

    2015-01-01

    The ETS factor ETV2 (aka ER71) is essential for the generation of the blood and vascular system, as ETV2 deficiency leads to a complete block in blood and endothelial cell formation and embryonic lethality in the mouse. However, the ETV2-mediated gene regulatory network and signaling governing hematopoietic and endothelial cell development are poorly understood. Here, we map ETV2 global binding sites and carry out in vitro differentiation of embryonic stem cells, and germ line and conditional knockout mouse studies to uncover mechanisms involved in the hemangiogenic fate commitment from mesoderm. We show that ETV2 binds to enhancers that specify hematopoietic and endothelial cell lineages. We find that the hemangiogenic progenitor population in the developing embryo can be identified as FLK1highPDGFRα−. Notably, these hemangiogenic progenitors are exclusively sensitive to ETV2-dependent FLK1 signaling. Importantly, ETV2 turns on other Ets genes, thereby establishing an ETS hierarchy. Consequently, the hematopoietic and endothelial cell program initiated by ETV2 is maintained partly by other ETS factors through an ETS switching mechanism. These findings highlight the critical role that transient ETV2 expression plays in the regulation of hematopoietic and endothelial cell lineage specification and stability. PMID:25802403

  14. Tumor necrosis factor-{alpha} enhanced fusions between oral squamous cell carcinoma cells and endothelial cells via VCAM-1/VLA-4 pathway

    SciTech Connect

    Song, Kai; Zhu, Fei; Zhang, Han-zhong; Shang, Zheng-jun

    2012-08-15

    Fusion between cancer cells and host cells, including endothelial cells, may strongly modulate the biological behavior of tumors. However, no one is sure about the driving factors and underlying mechanism involved in such fusion. We hypothesized in this study that inflammation, one of the main characteristics in tumor microenvironment, serves as a prominent catalyst for fusion events. Our results showed that oral cancer cells can fuse spontaneously with endothelial cells in co-culture and inflammatory cytokine tumor necrosis factor-{alpha} (TNF-{alpha}) increased fusion of human umbilical vein endothelium cells and oral cancer cells by up to 3-fold in vitro. Additionally, human oral squamous cell carcinoma cell lines and 35 out of 50 (70%) oral squamous carcinoma specimens express VLA-4, an integrin, previously implicated in fusions between human peripheral blood CD34-positive cells and murine cardiomyocytes. Expression of VCAM-1, a ligand for VLA-4, was evident on vascular endothelium of oral squamous cell carcinoma. Moreover, immunocytochemistry and flow cytometry analysis revealed that expression of VCAM-1 increased obviously in TNF-{alpha}-stimulated endothelial cells. Anti-VLA-4 or anti-VCAM-1 treatment can decrease significantly cancer-endothelial adhesion and block such fusion. Collectively, our results suggested that TNF-{alpha} could enhance cancer-endothelial cell adhesion and fusion through VCAM-1/VLA-4 pathway. This study provides insights into regulatory mechanism of cancer-endothelial cell fusion, and has important implications for the development of novel therapeutic strategies for prevention of metastasis. -- Highlights: Black-Right-Pointing-Pointer Spontaneous oral cancer-endothelial cell fusion. Black-Right-Pointing-Pointer TNF-{alpha} enhanced cell fusions. Black-Right-Pointing-Pointer VCAM-1/VLA-4 expressed in oral cancer. Black-Right-Pointing-Pointer TNF-{alpha} increased expression of VCAM-1 on endothelial cells. Black

  15. Comparative Evaluation for Potential Differentiation of Endothelial Progenitor Cells and Mesenchymal Stem Cells into Endothelial-Like Cells

    PubMed Central

    Sabry, Dina; Noh, Olfat; Samir, Mai

    2016-01-01

    Understanding the mechanisms of vascular remodeling could lead to more effective treatments for ischemic conditions. We aimed to compare between the abilities of both human Wharton jelly derived mesenchymal stem cells (hMSCs) and human cord blood endothelial progenitor cells (hEPCs) and CD34+ to induce angiogenesis in vitro. hMSCs, hEPCs, and CD34+ were isolated from human umbilical cord blood using microbead (MiniMacs). The cells characterization was assessed by flow cytometry following culture and real-time PCR for vascular endothelial growth factor receptor 2 (VEGFR2) and von Willebrand factor (vWF) to prove stem cells differentiation. The study revealed successful isolation of hEPCs, CD34+, and hMSCs. The hMSCs were identified by gaining CD29+ and CD44+ using FACS analysis. The hEPCs were identified by having CD133+, CD34+, and KDR. The potential ability of hEPCs and CD34+ to differentiate into endothelial-like cells was more than hMSCs. This finding was assessed morphologically in culture and by higher significant VEGFR2 and vWF genes expression (p<0.05) in differentiated hEPCs and CD34+ compared to differentiated hMSCs. hEPCs and CD34+ differentiation into endothelial-like cells were much better than that of hMSCs. PMID:27426085

  16. Radiation Effects on the Cytoskeleton of Endothelial Cells and Endothelial Monolayer Permeability

    SciTech Connect

    Gabrys, Dorota; Greco, Olga; Patel, Gaurang; Prise, Kevin M.; Tozer, Gillian M.; Kanthou, Chryso

    2007-12-01

    Purpose: To investigate the effects of radiation on the endothelial cytoskeleton and endothelial monolayer permeability and to evaluate associated signaling pathways, which could reveal potential mechanisms of known vascular effects of radiation. Methods and Materials: Cultured endothelial cells were X-ray irradiated, and actin filaments, microtubules, intermediate filaments, and vascular endothelial (VE)-cadherin junctions were examined by immunofluorescence. Permeability was determined by the passage of fluorescent dextran through cell monolayers. Signal transduction pathways were analyzed using RhoA, Rho kinase, and stress-activated protein kinase-p38 (SAPK2/p38) inhibitors by guanosine triphosphate-RhoA activation assay and transfection with RhoAT19N. The levels of junction protein expression and phosphorylation of myosin light chain and SAPK2/p38 were assessed by Western blotting. The radiation effects on cell death were verified by clonogenic assays. Results: Radiation induced rapid and persistent actin stress fiber formation and redistribution of VE-cadherin junctions in microvascular, but not umbilical vein endothelial cells, and microtubules and intermediate filaments remained unaffected. Radiation also caused a rapid and persistent increase in microvascular permeability. RhoA-guanosine triphosphatase and Rho kinase were activated by radiation and caused phosphorylation of downstream myosin light chain and the observed cytoskeletal and permeability changes. SAPK2/p38 was activated by radiation but did not influence either the cytoskeleton or permeability. Conclusion: This study is the first to show rapid activation of the RhoA/Rho kinase by radiation in endothelial cells and has demonstrated a link between this pathway and cytoskeletal remodeling and permeability. The results also suggest that the RhoA pathway might be a useful target for modulating the permeability and other effects of radiation for therapeutic gain.

  17. Impact of simulated microgravity on microvascular endothelial cell apoptosis.

    PubMed

    Kang, Chun-Yan; Zou, Lin; Yuan, Ming; Wang, Yang; Li, Tian-Zhi; Zhang, Ye; Wang, Jun-Feng; Li, Yan; Deng, Xiao-Wei; Liu, Chang-Ting

    2011-09-01

    Cardiovascular deconditioning is known to occur in astronauts exposed to microgravity. Endothelial dysfunction at microcirculatory sites might contribute to cardiovascular deconditioning induced by weightlessness. Recent studies have reported changes in the morphology and gene expression of endothelial cells exposed to conditions of simulated microgravity. The present study was aimed at examining the effects of microgravity on the apoptosis of microvascular endothelial cells and the mechanism underlying these effects. We simulated a microgravity environment and found that microgravity induced microvascular endothelial cell apoptosis and that this effect was correlated with the downregulation of the PI3K/Akt pathway, increased expression of NF-κB, and depolymerization of F-actin. These findings may provide important insights into the origin of the adverse physiological changes occurring due to exposure to microgravity conditions. PMID:21287193

  18. Lack of vimentin impairs endothelial differentiation of embryonic stem cells.

    PubMed

    Boraas, Liana C; Ahsan, Tabassum

    2016-01-01

    The cytoskeletal filament vimentin is inherent to the endothelial phenotype and is critical for the proper function of endothelial cells in adult mice. It is unclear, however, if the presence of vimentin is necessary during differentiation to the endothelial phenotype. Here we evaluated gene and protein expression of differentiating wild type embryonic stem cells (WT ESCs) and vimentin knockout embryonic stem cells (VIM -/- ESCs) using embryoid bodies (EBs) formed from both cell types. Over seven days of differentiation VIM -/- EBs had altered morphology compared to WT EBs, with a rippled outer surface and a smaller size due to decreased proliferation. Gene expression of pluripotency markers decreased similarly for EBs of both cell types; however, VIM -/- EBs had impaired differentiation towards the endothelial phenotype. This was quantified with decreased expression of markers along the specification pathway, specifically the early mesodermal marker Brachy-T, the lateral plate mesodermal marker FLK1, and the endothelial-specific markers TIE2, PECAM, and VE-CADHERIN. Taken together, these results indicate that the absence of vimentin impairs spontaneous differentiation of ESCs to the endothelial phenotype in vitro. PMID:27480130

  19. Lack of vimentin impairs endothelial differentiation of embryonic stem cells

    PubMed Central

    Boraas, Liana C.; Ahsan, Tabassum

    2016-01-01

    The cytoskeletal filament vimentin is inherent to the endothelial phenotype and is critical for the proper function of endothelial cells in adult mice. It is unclear, however, if the presence of vimentin is necessary during differentiation to the endothelial phenotype. Here we evaluated gene and protein expression of differentiating wild type embryonic stem cells (WT ESCs) and vimentin knockout embryonic stem cells (VIM −/− ESCs) using embryoid bodies (EBs) formed from both cell types. Over seven days of differentiation VIM −/− EBs had altered morphology compared to WT EBs, with a rippled outer surface and a smaller size due to decreased proliferation. Gene expression of pluripotency markers decreased similarly for EBs of both cell types; however, VIM −/− EBs had impaired differentiation towards the endothelial phenotype. This was quantified with decreased expression of markers along the specification pathway, specifically the early mesodermal marker Brachy-T, the lateral plate mesodermal marker FLK1, and the endothelial-specific markers TIE2, PECAM, and VE-CADHERIN. Taken together, these results indicate that the absence of vimentin impairs spontaneous differentiation of ESCs to the endothelial phenotype in vitro. PMID:27480130

  20. The effects of glucocorticoids on cultured human endothelial cells.

    PubMed

    Maca, R D; Fry, G L; Hoak, J C

    1978-04-01

    The effects of hydrocortisone, dexamethasone and prednisone on the morphology, replication, DNA synthesis, cell protein content and protein synthesis of cultured, human endothelial cells were evaluated. After culturing the cells with these glucocorticoids for 24-48 h, the cells covered a greater portion of the culture surface area. The mean surface area of the individual endothelial cell treated with glucocorticoids was 1.53 times greater than that of the untreated control endothelial cell. When compared with controls, the endothelial cover provided by the cells treated with glucocorticoids was more extensive and in many instances covered the entire culture surface. The change in morphology was associated with an increase in protein synthesis and protein content of the cells without an increase in DNA synthesis or cellular replication. Dexamethasone was approximately 10-fold more effective than hydrocortisone, while prednisone was the least effective. Aldosterone, DOCA, testosterone, progesterone, oestradiol and oestriol were ineffective. These studies indicate that glucocorticoids can alter the morphology and biochemistry of cultured endothelial cells and may have implications for the effects of steroids in the treatment of thrombocytopenic states and vascular disorders in man. PMID:646949

  1. Adenoviral modification of mouse brain derived endothelial cells, bEnd3, to induce apoptosis by vascular endothelial growth factor.

    PubMed

    Mitsuuchi, Y; Powell, D R; Gallo, J M

    2006-02-01

    A second generation genetically-engineered cell-based drug delivery system, referred to as apoptotic-induced drug delivery (AIDD), was developed using endothelial cells (ECs) that undergo apoptosis upon binding of vascular endothelial growth factor (VEGF) to a Flk-1:Fas fusion protein (FF). This new AIDD was redesigned using mouse brain derived ECs, bEnd3 cells, and an adenovirus vector in order to enhance and control the expression of FF. The FF was tagged with a HA epitope (FFHA) and designed to be coexpressed with green fluorescence protein (GFP) by the regulation of cytomegalovirus promoters in the adenovirus vector. bEnd3 cells showed favorable coexpression of FFHA and GFP consistent with the multiplicity of infection of the adenovirus. Immunofluorescence analysis demonstrated that FFHA was localized at the plasma membrane, whereas GFP was predominantly located in the cytoplasm of ECs. Cell death was induced by VEGF, but not by platelet derived growth factor or fibroblast growth factor in a dose-dependent manner (range 2-20 ng/ml), and revealed caspase-dependent apoptotic profiles. The FFHA expressing bEnd3 cells underwent apoptosis when cocultured with a glioma cell (SF188V+) line able to overexpress VEGF. The combined data indicated that the FFHA adenovirus system can induce apoptotic signaling in ECs in response to VEGF, and thus, is an instrumental modification to the development of AIDD. PMID:16247462

  2. Expression of thrombospondins by endothelial cells. Injury is correlated with TSP-1.

    PubMed Central

    Reed, M. J.; Iruela-Arispe, L.; O'Brien, E. R.; Truong, T.; LaBell, T.; Bornstein, P.; Sage, E. H.

    1995-01-01

    The thrombospondins (TSP-1, -2, and -3) comprise a family of proteins that are homologous at the carboxy terminus but have unique sequences at the amino terminus that might be correlated with the regulation of cell behavior. To investigate the expression of TSP-1, -2, and -3 in endothelial cells, we examined developing murine blood vessels and human atherosclerotic plaques by in situ hybridization. The expression of TSP-1 was also characterized in cultured bovine aortic endothelial cells. Expression of TSP-2 was seen in the dorsal aorta as early as embryonic day 10; TSP-1 was not detected in endothelial cells until later stages, and TSP-3 was not apparent in the vasculature. In atherosclerotic specimens, TSP-1 mRNA was detected in many intraplaque microvessels and in the endothelium lining the atheromatous plaque; TSP-2 was absent from these regions. Cultured bovine aortic endothelial cells did not transcribe TSP-2 mRNA at detectable levels. There were high steady-state levels of TSP-1 mRNA in subconfluent bovine aortic endothelial cells before confluence and at the wound edge after injury of the cell monolayer, with maximal expression of TSP-1 in cultures at a time during which approximately 35% of the cells were in S phase. As the majority of these cells subsequently undergo mitosis, these data are consistent with TSP-1 as an inhibitor of endothelial cell proliferation that functions in G1. These results support the conclusion that, despite sequence homology, the TSPs have distinct functions in vascular biology. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:7573352

  3. Role of Chinese herbal medicinal ingredients in secretion of cytokines by PCV2-induced endothelial cells.

    PubMed

    Hu, Yiyi; He, Kongwang; Wang, Xiaomin

    2016-01-01

    While T-lymphocytes are the major cell type responsible for host responses to a virus (including induction of inflammatory responses to aid in ultimate removal of virus), other cells, including macrophages, epithelial and dendritic cells also have key roles. Endothelial cells also play important roles in physiologic/pathologic processes, like inflammation, during viral infections. As endothelial cells can be activated to release various endogenous compounds, including some cytokines, ex vivo measures of cytokine formation by the cells can be used to indirectly assess any potential endothelial dysfunction in situ. The research presented here sought to investigate potential immunolomodulatory effects of five saponins on endothelial cells: Saikosaponins A (SSA) and D (SSD), Panax Notoginseng Saponin (PNS) and Notoginsenoside R1 (SR1) and Anemoside B4 (AB4). For this, cells (porcine iliac artery endothelial line) were challenged with a virus isolate PCV2-AH for 24 h and then treated with the test saponin (at 1, 5 or 10 μg/ml) for an additional 24 h at 37 °C. The culture supernatants were then collected and analyzed for interleukin (IL)-2, -4 and -10, as well as interferon (IFN)-γ by ELISA. The results revealed that PNS and SR1 inhibited the production of IL-4; PNS, SR1 and AB4 inhibited the secretion of IL-10; SSA, SSD and PNS up-regulated IL-2 expression; SSA and SSD increased the level of IFNγ. All these changes were significant. Taken together, the data suggested these saponins might potentially have a capacity to regulate immune responses in vivo via changes in production of these select cytokines by infected endothelial cells. Nevertheless, the impact of these agents on other key cell types involved in anti-viral responses, including T-lymphocytes, remains to be determined. PMID:25721049

  4. Potential proinflammatory effects of hydroxyapatite nanoparticles on endothelial cells in a monocyte–endothelial cell coculture model

    PubMed Central

    Liu, Xin; Sun, Jiao

    2014-01-01

    Currently, synthetic hydroxyapatite nanoparticles (HANPs) are used in nanomedicine fields. The delivery of nanomedicine to the bloodstream exposes the cardiovascular system to a potential threat. However, the possible adverse cardiovascular effects of HANPs remain unclear. Current observations using coculture models of endothelial cells and monocytes with HANPs to mimic the complex physiological functionality of the vascular system demonstrate that monocytes could play an important role in the mechanisms of endothelium dysfunction induced by the exposure to HANPs. Our transmission electron microscopy analysis revealed that both monocytes and endothelial cells could take up HANPs. Moreover, our findings demonstrated that at a subcytotoxic dose, HANPs alone did not cause direct endothelial cell injury, but they did induce an indirect activation of endothelial cells, resulting in increased interleukin-6 production and elevated adhesion molecule expression after coculture with monocytes. The potential proinflammatory effect of HANPs is largely mediated by the release of soluble factors from the activated monocytes, leading to an inflammatory response of the endothelium, which is possibly dependent on p38/c-Jun N-terminal kinase, and nuclear factor-kappa B signaling activation. The use of in vitro monocyte–endothelial cell coculture models for the biocompatibility assessment of HANPs could reveal their potential proinflammatory effects on endothelial cells, suggesting that exposure to HANPs possibly increases the risk of cardiovascular disease. PMID:24648726

  5. Tumour-cell-induced endothelial cell necroptosis via death receptor 6 promotes metastasis.

    PubMed

    Strilic, Boris; Yang, Lida; Albarrán-Juárez, Julián; Wachsmuth, Laurens; Han, Kang; Müller, Ulrike C; Pasparakis, Manolis; Offermanns, Stefan

    2016-08-11

    Metastasis is the leading cause of cancer-related death in humans. It is a complex multistep process during which individual tumour cells spread primarily through the circulatory system to colonize distant organs. Once in the circulation, tumour cells remain vulnerable, and their metastatic potential largely depends on a rapid and efficient way to escape from the blood stream by passing the endothelial barrier. Evidence has been provided that tumour cell extravasation resembles leukocyte transendothelial migration. However, it remains unclear how tumour cells interact with endothelial cells during extravasation and how these processes are regulated on a molecular level. Here we show that human and murine tumour cells induce programmed necrosis (necroptosis) of endothelial cells, which promotes tumour cell extravasation and metastasis. Treatment of mice with the receptor-interacting serine/threonine-protein kinase 1 (RIPK1)-inhibitor necrostatin-1 or endothelial-cell-specific deletion of RIPK3 reduced tumour-cell-induced endothelial necroptosis, tumour cell extravasation and metastasis. In contrast, pharmacological caspase inhibition or endothelial-cell-specific loss of caspase-8 promoted these processes. We furthermore show in vitro and in vivo that tumour-cell-induced endothelial necroptosis leading to extravasation and metastasis requires amyloid precursor protein expressed by tumour cells and its receptor, death receptor 6 (DR6), on endothelial cells as the primary mediators of these effects. Our data identify a new mechanism underlying tumour cell extravasation and metastasis, and suggest endothelial DR6-mediated necroptotic signalling pathways as targets for anti-metastatic therapies. PMID:27487218

  6. Differential Effects of Isoxazole-9 on Neural Stem/Progenitor Cells, Oligodendrocyte Precursor Cells, and Endothelial Progenitor Cells

    PubMed Central

    Maki, Takakuni; Shindo, Akihiro; Osumi, Noriko; Zhao, Jing; Lin, Hong; Holder, Julie C.; Chuang, Tsu Tshen; McNeish, John D.; Arai, Ken; Lo, Eng H.

    2015-01-01

    Adult mammalian brain can be plastic after injury and disease. Therefore, boosting endogenous repair mechanisms would be a useful therapeutic approach for neurological disorders. Isoxazole-9 (Isx-9) has been reported to enhance neurogenesis from neural stem/progenitor cells (NSPCs). However, the effects of Isx-9 on other types of progenitor/precursor cells remain mostly unknown. In this study, we investigated the effects of Isx-9 on the three major populations of progenitor/precursor cells in brain: NSPCs, oligodendrocyte precursor cells (OPCs), and endothelial progenitor cells (EPCs). Cultured primary NSPCs, OPCs, or EPCs were treated with various concentrations of Isx-9 (6.25, 12.5, 25, 50 μM), and their cell numbers were counted in a blinded manner. Isx-9 slightly increased the number of NSPCs and effectively induced neuronal differentiation of NSPCs. However, Isx-9 significantly decreased OPC number in a concentration-dependent manner, suggesting cytotoxicity. Isx-9 did not affect EPC cell number. But in a matrigel assay of angiogenesis, Isx-9 significantly inhibited tube formation in outgrowth endothelial cells derived from EPCs. This potential anti-tube-formation effect of Isx-9 was confirmed in a brain endothelial cell line. Taken together, our data suggest that mechanisms and targets for promoting stem/progenitor cells in the central nervous system may significantly differ between cell types. PMID:26407349

  7. Glioma-associated endothelial cells show evidence of replicative senescence

    SciTech Connect

    Charalambous, Christiana; Virrey, Jenilyn; Kardosh, Adel; Jabbour, Mark N.; Qazi-Abdullah, Lubna; Pen, Ligaya; Zidovetzki, Raphael; Schoenthal, Axel H.; Chen, Thomas C.; Hofman, Florence M. . E-mail: hofman@usc.edu

    2007-04-01

    The innately programmed process of replicative senescence has been studied extensively with respect to cancer, but primarily from the perspective of tumor cells overcoming this stringent innate barrier and acquiring the capacity for unlimited proliferation. In this study, we focus on the potential role of replicative senescence affecting the non-transformed endothelial cells of the blood vessels within the tumor microenvironment. Based on the well-documented aberrant structural and functional features of blood vessels within solid tumors, we hypothesized that tumor-derived factors may lead to premature replicative senescence in tumor-associated brain endothelial cells (TuBEC). We show here that glioma tissue, but not normal brain tissue, contains cells that express the signature of replicative senescence, senescence-associated {beta}-galactosidase (SA-{beta}-gal), on CD31-positive endothelial cells. Primary cultures of human TuBEC stain for SA-{beta}-gal and exhibit characteristics of replicative senescence, including increased levels of the cell cycle inhibitors p21 and p27, increased resistance to cytotoxic drugs, increased growth factor production, and inability to proliferate. These data provide the first demonstration that tumor-derived brain endothelial cells may have reached an end-stage of differentiation known as replicative senescence and underscore the need for anti-angiogenic therapies to target this unique tumor-associated endothelial cell population.

  8. Nanoparticle accumulation and transcytosis in brain endothelial cell layers

    NASA Astrophysics Data System (ADS)

    Ye, Dong; Raghnaill, Michelle Nic; Bramini, Mattia; Mahon, Eugene; Åberg, Christoffer; Salvati, Anna; Dawson, Kenneth A.

    2013-10-01

    The blood-brain barrier (BBB) is a selective barrier, which controls and limits access to the central nervous system (CNS). The selectivity of the BBB relies on specialized characteristics of the endothelial cells that line the microvasculature, including the expression of intercellular tight junctions, which limit paracellular permeability. Several reports suggest that nanoparticles have a unique capacity to cross the BBB. However, direct evidence of nanoparticle transcytosis is difficult to obtain, and we found that typical transport studies present several limitations when applied to nanoparticles. In order to investigate the capacity of nanoparticles to access and transport across the BBB, several different nanomaterials, including silica, titania and albumin- or transferrin-conjugated gold nanoparticles of different sizes, were exposed to a human in vitro BBB model of endothelial hCMEC/D3 cells. Extensive transmission electron microscopy imaging was applied in order to describe nanoparticle endocytosis and typical intracellular localisation, as well as to look for evidence of eventual transcytosis. Our results show that all of the nanoparticles were internalised, to different extents, by the BBB model and accumulated along the endo-lysosomal pathway. Rare events suggestive of nanoparticle transcytosis were also observed for several of the tested materials.The blood-brain barrier (BBB) is a selective barrier, which controls and limits access to the central nervous system (CNS). The selectivity of the BBB relies on specialized characteristics of the endothelial cells that line the microvasculature, including the expression of intercellular tight junctions, which limit paracellular permeability. Several reports suggest that nanoparticles have a unique capacity to cross the BBB. However, direct evidence of nanoparticle transcytosis is difficult to obtain, and we found that typical transport studies present several limitations when applied to nanoparticles. In

  9. MicroRNAs in Hyperglycemia Induced Endothelial Cell Dysfunction.

    PubMed

    Silambarasan, Maskomani; Tan, Jun Rong; Karolina, Dwi Setyowati; Armugam, Arunmozhiarasi; Kaur, Charanjit; Jeyaseelan, Kandiah

    2016-01-01

    Hyperglycemia is closely associated with prediabetes and Type 2 Diabetes Mellitus. Hyperglycemia increases the risk of vascular complications such as diabetic retinopathy, diabetic nephropathy, peripheral vascular disease and cerebro/cardiovascular diseases. Under hyperglycemic conditions, the endothelial cells become dysfunctional. In this study, we investigated the miRNA expression changes in human umbilical vein endothelial cells exposed to different glucose concentrations (5, 10, 25 and 40 mM glucose) and at various time intervals (6, 12, 24 and 48 h). miRNA microarray analyses showed that there is a correlation between hyperglycemia induced endothelial dysfunction and miRNA expression. In silico pathways analyses on the altered miRNA expression showed that the majority of the affected biological pathways appeared to be associated to endothelial cell dysfunction and apoptosis. We found the expression of ten miRNAs (miR-26a-5p, -26b-5p, 29b-3p, -29c-3p, -125b-1-3p, -130b-3p, -140-5p, -192-5p, -221-3p and -320a) to increase gradually with increasing concentration of glucose. These miRNAs were also found to be involved in endothelial dysfunction. At least seven of them, miR-29b-3p, -29c-3p, -125b-1-3p, -130b-3p, -221-3p, -320a and -192-5p, can be correlated to endothelial cell apoptosis. PMID:27070575

  10. MicroRNAs in Hyperglycemia Induced Endothelial Cell Dysfunction

    PubMed Central

    Silambarasan, Maskomani; Tan, Jun Rong; Karolina, Dwi Setyowati; Armugam, Arunmozhiarasi; Kaur, Charanjit; Jeyaseelan, Kandiah

    2016-01-01

    Hyperglycemia is closely associated with prediabetes and Type 2 Diabetes Mellitus. Hyperglycemia increases the risk of vascular complications such as diabetic retinopathy, diabetic nephropathy, peripheral vascular disease and cerebro/cardiovascular diseases. Under hyperglycemic conditions, the endothelial cells become dysfunctional. In this study, we investigated the miRNA expression changes in human umbilical vein endothelial cells exposed to different glucose concentrations (5, 10, 25 and 40 mM glucose) and at various time intervals (6, 12, 24 and 48 h). miRNA microarray analyses showed that there is a correlation between hyperglycemia induced endothelial dysfunction and miRNA expression. In silico pathways analyses on the altered miRNA expression showed that the majority of the affected biological pathways appeared to be associated to endothelial cell dysfunction and apoptosis. We found the expression of ten miRNAs (miR-26a-5p, -26b-5p, 29b-3p, -29c-3p, -125b-1-3p, -130b-3p, -140-5p, -192-5p, -221-3p and -320a) to increase gradually with increasing concentration of glucose. These miRNAs were also found to be involved in endothelial dysfunction. At least seven of them, miR-29b-3p, -29c-3p, -125b-1-3p, -130b-3p, -221-3p, -320a and -192-5p, can be correlated to endothelial cell apoptosis. PMID:27070575

  11. Carotid Repair Using Autologous Adipose-Derived Endothelial Cells

    PubMed Central

    Froehlich, Harald; Gulati, Rajiv; Boilson, Barry; Witt, Tyra; Harbuzariu, Adriana; Kleppe, Laurel; Dietz, Allan B.; Lerman, Amir; Simari, Robert D.

    2009-01-01

    Background and Purpose Adipose tissue is an abundant source of endothelial cells as well as stem and progenitor cells which can develop an endothelial phenotype. It has been demonstrated that these cells have distinct angiogenic properties in vitro and in vivo. However, whether these cells have the capacity to directly improve large vessel form and function following vascular injury remains unknown. To define whether delivery of adipose-derived endothelial cells (ADECs) would improve healing of injured carotid arteries, a rabbit model of acute arterial injury was employed. Methods Autologous rabbit ADECS were generated utilizing defined culture conditions. To test the ability of ADECs to enhance carotid artery repair, cells were delivered intra-arterially following acute balloon injury. Additional delivery studies were performed following functional selection of cells prior to delivery. Results Following rabbit omental fat harvest and digestion, a proliferative, homogenous, and distinctly endothelial population of ADECs was identified. Direct delivery of autologous ADECs resulted in marked re-endothelialization 48 hours following acute vascular injury as compared to saline controls (82.2 ±26.9% vs 4.2±3.0% p<0.001). Delivery of ADECs that were selected for their ability to take up acetylated LDL significantly improved vasoreactivity and decreased intimal formation following vascular injury. Conclusions Taken together, these data suggest that ADECs represent an autologous source of proliferative endothelial cells which demonstrate the capacity to rapidly improve re-endothelialization, improve vascular reactivity, and decrease intimal formation in a carotid artery injury model. PMID:19286583

  12. Endothelial progenitor cells in acute ischemic stroke

    PubMed Central

    Martí-Fàbregas, Joan; Crespo, Javier; Delgado-Mederos, Raquel; Martínez-Ramírez, Sergi; Peña, Esther; Marín, Rebeca; Dinia, Lavinia; Jiménez-Xarrié, Elena; Fernández-Arcos, Ana; Pérez-Pérez, Jesús; Querol, Luis; Suárez-Calvet, Marc; Badimon, Lina

    2013-01-01

    Objectives The levels of circulating endothelial progenitor cells (EPCs) in ischemic stroke have not been studied extensively and reported results are inconsistent. We aimed to investigate the time course, the prognostic relevance, and the variables associated with EPC counts in patients with ischemic stroke at different time points. Material and methods We studied prospectively 146 consecutive patients with ischemic stroke within the first 48 h from the onset of symptoms (baseline). We evaluated demographic data, classical vascular risk factors, treatment with thrombolysis and statins, stroke etiology, National Institute of Health and Stroke Scale score and outcome (favorable when Rankin scale score 0–2). Blood samples were collected at baseline, at day 7 after stroke (n = 121) and at 3 months (n = 92). The EPC were measured by flow cytometry. Results We included 146 patients with a mean age of 70.8 ± 12.2 years. The circulating EPC levels were higher on day 7 than at baseline or at 3 months (P = 0.045). Pretreatment with statins (odds ratio [OR] 3.11, P = 0.008) and stroke etiology (P = 0.032) were predictive of EPC counts in the baseline sample. EPC counts were not associated with stroke severity or functional outcome in all the patients. However, using multivariate analyses, a better functional outcome was found in patients with higher EPC counts in large-artery atherosclerosis and small-vessel disease etiologic subtypes. Conclusions After acute ischemic stroke, circulating EPC counts peaked at day 7. Pretreatment with statins increased the levels of EPC. In patients with large-artery atherosclerosis and small-vessel disease subtypes, higher counts were related to better outcome at 3 months. PMID:24363968

  13. CXCL12 Mediates Trophic Interactions between Endothelial and Tumor Cells in Glioblastoma

    PubMed Central

    Choe, Eun Joo; Woerner, B. Mark; Jackson, Erin; Sun, Tao; Leonard, Jeffrey; Piwnica-Worms, David; Rubin, Joshua B.

    2012-01-01

    Emerging evidence suggests endothelial cells (EC) play a critical role in promoting Glioblastoma multiforme (GBM) cell proliferation and resistance to therapy. The molecular basis for GBM-EC interactions is incompletely understood. We hypothesized that the chemokine CXCL12 and its receptor CXCR4 could mediate direct interactions between GBM cells and tumor-associated endothelial cells and that disruption of this interaction might be the molecular basis for the anti-tumor effects of CXCR4 antagonists. We investigated this possibility in vivo and in an in vitro co-culture model that incorporated extracellular matrix, primary human brain microvascular ECs (HBMECs) and either an established GBM cell line or primary GBM specimens. Depletion of CXCR4 in U87 GBM cells blocked their growth as intracranial xenografts indicating that tumor cell CXCR4 is required for tumor growth in vivo. In vitro, co-culture of either U87 cells or primary GBM cells with HBMECs resulted in their co-localization and enhanced GBM cell growth. Genetic manipulation of CXCL12 expression and pharmacological inhibition of its receptors CXCR4 and CXCR7 revealed that the localizing and trophic effects of endothelial cells on GBM cells were dependent upon CXCL12 and CXCR4. These findings indicate that the CXCL12/CXCR4 pathway directly mediates endothelial cell trophic function in GBMs and that inhibition of CXCL12-CXCR4 signaling may uniquely target this activity. Therapeutic disruption of endothelial cell trophic functions could complement the structural disruption of anti-angiogenic regimens and, in combination, might also improve the efficacy of radiation and chemotherapy in treating GBMs. PMID:22427929

  14. Inhibition of cyclooxygenase (COX)-2 affects endothelial progenitor cell proliferation

    SciTech Connect

    Colleselli, Daniela; Bijuklic, Klaudija; Mosheimer, Birgit A.; Kaehler, Christian M. . E-mail: C.M.Kaehler@uibk.ac.at

    2006-09-10

    Growing evidence indicates that inducible cyclooxygenase-2 (COX-2) is involved in the pathogenesis of inflammatory disorders and various types of cancer. Endothelial progenitor cells recruited from the bone marrow have been shown to be involved in the formation of new vessels in malignancies and discussed for being a key point in tumour progression and metastasis. However, until now, nothing is known about an interaction between COX and endothelial progenitor cells (EPC). Expression of COX-1 and COX-2 was detected by semiquantitative RT-PCR and Western blot. Proliferation kinetics, cell cycle distribution and rate of apoptosis were analysed by MTT test and FACS analysis. Further analyses revealed an implication of Akt phosphorylation and caspase-3 activation. Both COX-1 and COX-2 expression can be found in bone-marrow-derived endothelial progenitor cells in vitro. COX-2 inhibition leads to a significant reduction in proliferation of endothelial progenitor cells by an increase in apoptosis and cell cycle arrest. COX-2 inhibition leads further to an increased cleavage of caspase-3 protein and inversely to inhibition of Akt activation. Highly proliferating endothelial progenitor cells can be targeted by selective COX-2 inhibition in vitro. These results indicate that upcoming therapy strategies in cancer patients targeting COX-2 may be effective in inhibiting tumour vasculogenesis as well as angiogenic processes.

  15. Role of Endothelial Cells in Myocardial Ischemia-Reperfusion Injury

    PubMed Central

    Singhal, Arun K.; Symons, J. David; Boudina, Sihem; Jaishy, Bharat; Shiu, Yan-Ting

    2014-01-01

    Minimizing myocardial ischemia-reperfusion injury has broad clinical implications and is a critical mediator of cardiac surgical outcomes. “Ischemic injury” results from a restriction in blood supply leading to a mismatch between oxygen supply and demand of a sufficient intensity and/or duration that leads to cell necrosis, whereas ischemia-reperfusion injury occurs when blood supply is restored after a period of ischemia and is usually associated with apoptosis (i.e. programmed cell death). Compared to vascular endothelial cells, cardiac myocytes are more sensitive to ischemic injury and have received the most attention in preventing myocardial ischemia-reperfusion injury. Many comprehensive reviews exist on various aspects of myocardial ischemia-reperfusion injury. The purpose of this review is to examine the role of vascular endothelial cells in myocardial ischemia-reperfusion injury, and to stimulate further research in this exciting and clinically relevant area. Two specific areas that are addressed include: 1) data suggesting that coronary endothelial cells are critical mediators of myocardial dysfunction after ischemia-reperfusion injury; and 2) the involvement of the mitochondrial permeability transition pore in endothelial cell death as a result of an ischemia-reperfusion insult. Elucidating the cellular signaling pathway(s) that leads to endothelial cell injury and/or death in response to ischemia-reperfusion is a key component to developing clinically applicable strategies that might minimize myocardial ischemia-reperfusion injury. PMID:25558187

  16. Secreted Endothelial Cell Factors Immobilized on Collagen Scaffolds Enhance the Recipient Endothelial Cell Environment

    PubMed Central

    Hamilton, Charlotte; Callanan, Anthony

    2016-01-01

    Abstract Strategies to design novel vascular scaffolds are a continuing aim in tissue engineering and often such designs encompass the use of recombinant factors to enhance the performance of the scaffold. The established use of cell secretion utilized in feeder systems and conditioned media offer a source of paracrine factors, which has potential to be used in tissue-engineered (TE) scaffolds. Here we utilize this principle from endothelial cells (ECs), to create a novel TE scaffold by harnessing secreted factors and immobilizing these to collagen scaffolds. This research revealed increased cellular attachment and positive angiogenic gene upregulation responses in recipient ECs grown on these conditioned scaffolds. Also, the conditioning method did not affect the mechanical structural integrity of the scaffolds. These results may advocate the potential use of this system to improve vascular scaffolds' in vivo performance. In addition, this process may be a future method utilized to improve other tissue engineering scaffold therapies. PMID:27057474

  17. CLO: The cell line ontology

    PubMed Central

    2014-01-01

    Background Cell lines have been widely used in biomedical research. The community-based Cell Line Ontology (CLO) is a member of the OBO Foundry library that covers the domain of cell lines. Since its publication two years ago, significant updates have been made, including new groups joining the CLO consortium, new cell line cells, upper level alignment with the Cell Ontology (CL) and the Ontology for Biomedical Investigation, and logical extensions. Construction and content Collaboration among the CLO, CL, and OBI has established consensus definitions of cell line-specific terms such as ‘cell line’, ‘cell line cell’, ‘cell line culturing’, and ‘mortal’ vs. ‘immortal cell line cell’. A cell line is a genetically stable cultured cell population that contains individual cell line cells. The hierarchical structure of the CLO is built based on the hierarchy of the in vivo cell types defined in CL and tissue types (from which cell line cells are derived) defined in the UBERON cross-species anatomy ontology. The new hierarchical structure makes it easier to browse, query, and perform automated classification. We have recently added classes representing more than 2,000 cell line cells from the RIKEN BRC Cell Bank to CLO. Overall, the CLO now contains ~38,000 classes of specific cell line cells derived from over 200 in vivo cell types from various organisms. Utility and discussion The CLO has been applied to different biomedical research studies. Example case studies include annotation and analysis of EBI ArrayExpress data, bioassays, and host-vaccine/pathogen interaction. CLO’s utility goes beyond a catalogue of cell line types. The alignment of the CLO with related ontologies combined with the use of ontological reasoners will support sophisticated inferencing to advance translational informatics development. PMID:25852852

  18. New thiazolidinediones affect endothelial cell activation and angiogenesis.

    PubMed

    Rudnicki, Martina; Tripodi, Gustavo L; Ferrer, Renila; Boscá, Lisardo; Pitta, Marina G R; Pitta, Ivan R; Abdalla, Dulcineia S P

    2016-07-01

    Thiazolidinediones (TZDs) are peroxisome proliferator-activated receptor-γ (PPARγ) agonists used in treating type 2 diabetes that may exhibit beneficial pleiotropic effects on endothelial cells. In this study, we characterized the effects of three new TZDs [GQ-32 (3-biphenyl-4-ylmethyl-5-(4-nitro-benzylidene)-thiazolidine-2,4-dione), GQ-169 (5-(4-chloro-benzylidene)-3-(2,6-dichloro-benzyl)-thiazolidine-2,4-dione), and LYSO-7 (5-(5-bromo-1H-indol-3-ylmethylene)-3-(4-chlorobenzyl)-thiazolidine-2,4-dione)] on endothelial cells. The effects of the new TZDs were evaluated on the production of nitric oxide (NO) and reactive oxygen species (ROS), cell migration, tube formation and the gene expression of adhesion molecules and angiogenic mediators in human umbilical vein endothelial cells (HUVECs). PPARγ activation by new TZDs was addressed with a reporter gene assay. The three new TZDs activated PPARγ and suppressed the tumor necrosis factor α-induced expression of vascular cell adhesion molecule 1 and intercellular adhesion molecule 1. GQ-169 and LYSO-7 also inhibited the glucose-induced ROS production. Although NO production assessed with 4-amino-5-methylamino-2',7'-difluorofluorescein-FM probe indicated that all tested TZDs enhanced intracellular levels of NO, only LYSO-7 treatment significantly increased the release of NO from HUVEC measured by chemiluminescence analysis of culture media. Additionally, GQ-32 and GQ-169 induced endothelial cell migration and tube formation by the up-regulation of angiogenic molecules expression, such as vascular endothelial growth factor A and interleukin 8. GQ-169 also increased the mRNA levels of basic fibroblast growth factor, and GQ-32 enhanced transforming growth factor-β expression. Together, the results of this study reveal that these new TZDs act as partial agonists of PPARγ and modulate endothelial cell activation and endothelial dysfunction besides to stimulate migration and tube formation. PMID:27108791

  19. Endothelial precursor cell-based therapy to target the pathologic angiogenesis and compensate tumor hypoxia.

    PubMed

    Collet, Guillaume; Szade, Krzysztof; Nowak, Witold; Klimkiewicz, Krzysztof; El Hafny-Rahbi, Bouchra; Szczepanek, Karol; Sugiyama, Daisuke; Weglarczyk, Kazimierz; Foucault-Collet, Alexandra; Guichard, Alan; Mazan, Andrzej; Nadim, Mahdi; Fasani, Fabienne; Lamerant-Fayel, Nathalie; Grillon, Catherine; Petoud, Stéphane; Beloeil, Jean-Claude; Jozkowicz, Alicja; Dulak, Jozef; Kieda, Claudine

    2016-01-28

    Hypoxia-inducing pathologies as cancer develop pathologic and inefficient angiogenesis which rules tumor facilitating microenvironment, a key target for therapy. As such, the putative ability of endothelial precursor cells (EPCs) to specifically home to hypoxic sites of neovascularization prompted to design optimized, site-specific, cell-mediated, drug-/gene-targeting approach. Thus, EPC lines were established from aorta-gonad-mesonephros (AGM) of murine 10.5 dpc and 11.5 dpc embryo when endothelial repertoire is completed. Lines representing early endothelial differentiation steps were selected: MAgEC10.5 and MagEC11.5. Distinct in maturation, they differently express VEGF receptors, VE-cadherin and chemokine/receptors. MAgEC11.5, more differentiated than MAgEC 10.5, displayed faster angiogenesis in vitro, different response to hypoxia and chemokines. Both MAgEC lines cooperated to tube-like formation with mature endothelial cells and invaded tumor spheroids through a vasculogenesis-like process. In vivo, both MAgEC-formed vessels established blood flow. Intravenously injected, both MAgECs invaded Matrigel(TM)-plugs and targeted tumors. Here we show that EPCs (MAgEC11.5) target tumor angiogenesis and allow local overexpression of hypoxia-driven soluble VEGF-receptor2 enabling drastic tumor growth reduction. We propose that such EPCs, able to target tumor angiogenesis, could act as therapeutic gene vehicles to inhibit tumor growth by vessel normalization resulting from tumor hypoxia alleviation. PMID:26577811

  20. Regulation of tissue morphogenesis by endothelial cell-derived signals

    PubMed Central

    Ramasamy, Saravana K.; Kusumbe, Anjali P.; Adams, Ralf H.

    2016-01-01

    Summary Endothelial cells form an extensive network of blood vessels that has numerous essential functions in the vertebrate body. In addition to their well-established role as a versatile transport network, blood vessels can induce organ formation or direct growth and differentiation processes by providing signals in a paracrine (angiocrine) fashion. Tissue repair also requires the local restoration of vasculature. Endothelial cells are emerging as important signaling centers that coordinate regeneration and help to prevent deregulated, disease-promoting processes. Vascular cells are also part of stem cell niches and play key roles in hematopoiesis, bone formation and neurogenesis. Here, we will review these newly identified roles of endothelial cells in the regulation of organ morphogenesis, maintenance and regeneration. PMID:25529933

  1. Human endothelial cell culture plaques induced by Rickettsia rickettsii.

    PubMed Central

    Walker, D H; Firth, W T; Edgell, C J

    1982-01-01

    Primary cultures of human umbilical vein endothelial cells were inoculated with plaque-purified Rickettsia rickettsii. After adsorption of rickettsiae, monolayers were overlaid with medium containing 0.5% agarose. Small plaques appeared on day 4 postinoculation, and distinct 1- to 2-mm plaques were observed on day 5. Plaquing efficiency was less than that of primary chicken embryo cells in the same medium. Human endothelial cell monolayers were susceptible to infection by R. rickettsii and underwent necrosis as demonstrated by supravital staining. The topographic association of endothelial cell necrosis and rickettsial infection in the plaque model confirmed the direct cytopathic effect of R. rickettsii on human endothelium. Uninfected cells appeared normal by supravital staining and transmission electron microscopy. This model offers the possibility of investigating rickettsial pathogenesis and mechanisms of enhanced severity of Rocky Mountain spotted fever in specific genetically determined conditions. Images PMID:6809631

  2. Using cultured endothelial cells to study endothelial barrier dysfunction: Challenges and opportunities.

    PubMed

    Aman, Jurjan; Weijers, Ester M; van Nieuw Amerongen, Geerten P; Malik, Asrar B; van Hinsbergh, Victor W M

    2016-08-01

    Despite considerable progress in the understanding of endothelial barrier regulation and the identification of approaches that have the potential to improve endothelial barrier function, no drug- or stem cell-based therapy is presently available to reverse the widespread vascular leak that is observed in acute respiratory distress syndrome (ARDS) and sepsis. The translational gap suggests a need to develop experimental approaches and tools that better mimic the complex environment of the microcirculation in which the vascular leak develops. Recent studies have identified several elements of this microenvironment. Among these are composition and stiffness of the extracellular matrix, fluid shear stress, interaction of endothelial cells (ECs) with pericytes, oxygen tension, and the combination of toxic and mechanic injurious stimuli. Development of novel cell culture techniques that integrate these elements would allow in-depth analysis of EC biology that closely approaches the (patho)physiological conditions in situ. In parallel, techniques to isolate organ-specific ECs, to define EC heterogeneity in its full complexity, and to culture patient-derived ECs from inducible pluripotent stem cells or endothelial progenitor cells are likely to advance the understanding of ARDS and lead to development of therapeutics. This review 1) summarizes the advantages and pitfalls of EC cultures to study vascular leak in ARDS, 2) provides an overview of elements of the microvascular environment that can directly affect endothelial barrier function, and 3) discusses alternative methods to bridge the gap between basic research and clinical application with the intent of improving the translational value of present EC culture approaches. PMID:27343194

  3. An exquisite cross-control mechanism among endothelial cell fate regulators directs the plasticity and heterogeneity of lymphatic endothelial cells

    PubMed Central

    Kang, Jinjoo; Yoo, Jaehyuk; Lee, Sunju; Tang, Wanli; Aguilar, Berenice; Ramu, Swapnika; Choi, Inho; Otu, Hasan H.; Shin, Jay W.; Dotto, G. Paolo; Koh, Chester J.; Detmar, Michael

    2010-01-01

    Arteriovenous-lymphatic endothelial cell fates are specified by the master regulators, namely, Notch, COUP-TFII, and Prox1. Whereas Notch is expressed in the arteries and COUP-TFII in the veins, the lymphatics express all 3 cell fate regulators. Previous studies show that lymphatic endothelial cell (LEC) fate is highly plastic and reversible, raising a new concept that all 3 endothelial cell fates may coreside in LECs and a subtle alteration can result in a reprogramming of LEC fate. We provide a molecular basis verifying this concept by identifying a cross-control mechanism among these cell fate regulators. We found that Notch signal down-regulates Prox1 and COUP-TFII through Hey1 and Hey2 and that activated Notch receptor suppresses the lymphatic phenotypes and induces the arterial cell fate. On the contrary, Prox1 and COUP-TFII attenuate vascular endothelial growth factor signaling, known to induce Notch, by repressing vascular endothelial growth factor receptor-2 and neuropilin-1. We show that previously reported podoplanin-based LEC heterogeneity is associated with differential expression of Notch1 in human cutaneous lymphatics. We propose that the expression of the 3 cell fate regulators is controlled by an exquisite feedback mechanism working in LECs and that LEC fate is a consequence of the Prox1-directed lymphatic equilibrium among the cell fate regulators. PMID:20351309

  4. Anti-vascular endothelial cell antibodies (AECA): comparison of two assay methods and clinical applications.

    PubMed

    Meyer, O; Kaiser, P; Haim, T; Edgell, C J; Pasquier, C; de Bandt, M; Bridey, F; Sellak, H; Lansaman, J; Kahn, M F

    1995-12-01

    Vascular endothelial cells may be a target for autoantibodies (AECAs) against membrane antigens that are constitutively expressed, induced or bound to their surface. To test this hypothesis, we used an enzyme-linked immunosorbent assay (ELISA) with two types of human endothelial cells as the substrate, i.e., human umbilical cord vein endothelial cells (HUVECs) or the hybrid cell line EAhy-926 obtained by fusion of HUVECs with the bronchial carcinoma cell line A549. A comparative functional study of these two cell types demonstrated that EAhy-926 cells produced only small amounts of VIII von Willebrand factor and tissular factor, did not contain Weibel Palade bodies visible under the electron microscope, and expressed ICAM-1 and selectin E in levels of no more than 15% of those expressed by human umbilical cord vein endothelial cells both after stimulation by bacterial lipopolysaccharide and under basal conditions. However, the two assay methods yielded similar IgG AECA titers when used on sera from patients with rheumatoid vasculitis or antiphospholipid syndrome. These antibodies did not exhibit cytotoxicity for cord vein or EAhy-926 cells. They were not specific for endothelium, since their activity decreased by a mean of 40% after incubation of sera with the epithelial cell line A549. A cross-sectional study of 565 sera demonstrated that anti-vascular IgG and IgM AECAs reactive with EAhy-926 cells occurred mainly in patients with dermatomyositis (IgG, 58%; IgM, 22%), systemic scleroderma (IgG, 48%; IgM, 18%), primary Sjögren's syndrome (IgG, 44%; IgM, 12%) and secondary and primary systemic vasculitides (IgG, 38%; IgM, 18%) including Wegener's granulomatosis. A longitudinal study in patients with Wegener's granulomatosis showed that AECAS were predictive of disease activity. PMID:8869215

  5. Brain endothelial cells and the glio-vascular complex.

    PubMed

    Wolburg, Hartwig; Noell, Susan; Mack, Andreas; Wolburg-Buchholz, Karen; Fallier-Becker, Petra

    2009-01-01

    We present and discuss the role of endothelial and astroglial cells in managing the blood-brain barrier (BBB) and aspects of pathological alterations in the BBB. The impact of astrocytes, pericytes, and perivascular cells on the induction and maintenance of the gliovascular unit is largely unidentified so far. An understanding of the signaling pathways that lie between these cell types and the endothelium and that possibly are mediated by components of the basal lamina is just beginning to emerge. The metabolism for the maintenance of the endothelial barrier is intimately linked to and dependent on the microenvironment of the brain parenchyma. We report the structure and function of the endothelial cells of brain capillaries by describing structures involved in the regulation of permeability, including transporter systems, caveolae, and tight junctions. There is increasing evidence that caveolae are not only vehicles for endo- and transcytosis, but also important regulators of tight-junction-based permeability. Tight junctions separate the luminal from the abluminal membrane domains of the endothelial cell ("fence function") and control the paracellular pathway ("gate function") thus representing the most significant structure of the BBB. In addition, the extracellular matrix between astrocytes/pericytes and endothelial cells contains numerous molecules with inherent signaling properties that have to be considered if we are to improve our knowledge of the complex and closely regulated BBB. PMID:18633647

  6. Invasion of Aortic and Heart Endothelial Cells by Porphyromonas gingivalis

    PubMed Central

    Deshpande, Rajashri G.; Khan, Mahfuz B.; Attardo Genco, Caroline

    1998-01-01

    Invasion of host cells is believed to be an important strategy utilized by a number of pathogens, which affords them protection from the host immune system. The connective tissues of the periodontium are extremely well vascularized, which allows invading microorganisms, such as the periodontal pathogen Porphyromonas gingivalis, to readily enter the bloodstream. However, the ability of P. gingivalis to actively invade endothelial cells has not been previously examined. In this study, we demonstrate that P. gingivalis can invade bovine and human endothelial cells as assessed by an antibiotic protection assay and by transmission and scanning electron microscopy. P. gingivalis A7436 was demonstrated to adhere to and to invade fetal bovine heart endothelial cells (FBHEC), bovine aortic endothelial cells (BAEC), and human umbilical vein endothelial cells (HUVEC). Invasion efficiencies of 0.1, 0.2, and 0.3% were obtained with BAEC, HUVEC, and FBHEC, respectively. Invasion of FBHEC and BAEC by P. gingivalis A7436 assessed by electron microscopy revealed the formation of microvillus-like extensions around adherent bacteria followed by the engulfment of the pathogen within vacuoles. Invasion of BAEC by P. gingivalis A7436 was inhibited by cytochalasin D, nocodazole, staurosporine, protease inhibitors, and sodium azide, indicating that cytoskeletal rearrangements, protein phosphorylation, energy metabolism, and P. gingivalis proteases are essential for invasion. In contrast, addition of rifampin, nalidixic acid, and chloramphenicol had little effect on invasion, indicating that bacterial RNA, DNA, and de novo protein synthesis are not required for P. gingivalis invasion of endothelial cells. Likewise de novo protein synthesis by endothelial cells was not required for invasion by P. gingivalis. P. gingivalis 381 was demonstrated to adhere to and to invade BAEC (0.11 and 0.1% efficiency, respectively). However, adherence and invasion of the corresponding fimA mutant DPG3, which

  7. Long-term evaluation of corneal endothelial cell transplantation.

    PubMed Central

    Mohay, J; Wood, T O; McLaughlin, B J

    1997-01-01

    PURPOSE: This report describes the clinical course, refractive changes, confocal microscopic and histological evaluation of corneal endothelial cell transplantation in rabbits with long-term follow-up. METHODS: Transplantation of corneal endothelial cells using a cell/carrier device was performed in 19 rabbits. Clinical evaluation between 1-25 months included slit-lamp examination, keratometry, retinoscopy and surface topography. Two grafts in rabbits with 12 and 24 month survivals were evaluated in vivo by 3D tandem scanning confocal microscopy. The same grafts were then processed for transmission electron microscopy. BrdU labeling of the grafted cells in one transplant was performed in order to distinguish between host and grafted endothelial cells. RESULTS: All grafts cleared and remained clear for an average of one year without signs of rejection or inflammation. Postoperative refraction data and topography of the transplants showed progressive development of myopia and steep corneas compared to the unoperated eyes in each case. Confocal microscopy in vivo demonstrated a regular hexagonal pattern of the transplanted endothelial cells and a thickened Descemet's membrane, which correlated with the light and electron microscopic findings. BrdU labeling of the grafted endothelial cells showed a homogenous labeling of cell nuclei 6 months after the transplantation. CONCLUSIONS: This study demonstrates that corneal endothelial cells grown on a biomaterial can be replaced and remain functional for a long period of time. Images FIGURE 1 FIGURE 2A FIGURE 2B FIGURE 2C FIGURE 3A FIGURE 3B FIGURE 4 FIGURE 5 FIGURE 6A FIGURE 6B FIGURE 7 FIGURE 8A FIGURE 8B FIGURE 8C FIGURE 8D FIGURE 8E FIGURE 8F FIGURE 9 PMID:9440167

  8. Preparation of chitosan films using different neutralizing solutions to improve endothelial cell compatibility.

    PubMed

    He, Qing; Ao, Qiang; Gong, Yandao; Zhang, Xiufang

    2011-12-01

    The development of chitosan-based constructs for application in large-size defects or highly vascularized tissues is still a challenging issue. The poor endothelial cell compatibility of chitosan hinders the colonization of vascular endothelial cells in the chitosan-based constructs, and retards the establishment of a functional microvascular network following implantation. The aim of the present study is to prepare chitosan films with different neutralization methods to improve their endothelial cell compatibility. Chitosan salt films were neutralized with either sodium hydroxide (NaOH) aqueous solution, NaOH ethanol solution, or ethanol solution without NaOH. The physicochemical properties and endothelial cell compatibility of the chitosan films were investigated. Results indicated that neutralization with different solutions affected the surface chemistry, swelling ratio, crystalline conformation, nanotopography, and mechanical properties of the chitosan films. The NaOH ethanol solution-neutralized chitosan film (Chi-NaOH/EtOH film) displayed a nanofiber-dominant surface, while the NaOH aqueous solution-neutralized film (Chi-NaOH/H(2)O film) and the ethanol solution-neutralized film (Chi-EtOH film) displayed nanoparticle-dominant surfaces. Moreover, the Chi-NaOH/EtOH films exhibited a higher stiffness as compared to the Chi-NaOH/H(2)O and Chi-EtOH films. Endothelial cell compatibility of the chitosan films was evaluated with a human microvascular endothelial cell line, HMEC-1. Compared with the Chi-NaOH/H(2)O and Chi-EtOH films, HMECs cultured on the Chi-NaOH/EtOH films fully spread and exhibited significantly higher levels of adhesion and proliferation, with retention of the endothelial phenotype and function. Our findings suggest that the surface nanotopography and mechanical properties contribute to determining the endothelial cell compatibility of chitosan films. The nature of the neutralizing solutions can affect the physicochemical properties and

  9. Molecular basis for globotriaosylceramide regulation and enzyme uptake in immortalized aortic endothelial cells from Fabry mice.

    PubMed

    Meng, Xing-Li; Day, Taniqua S; McNeill, Nathan; Ashcraft, Paula; Frischmuth, Thomas; Cheng, Seng H; Liu, Zhi-Ping; Shen, Jin-Song; Schiffmann, Raphael

    2016-05-01

    Fabry disease is caused by deficient activity of α-galactosidase A and subsequent intracellular accumulation of glycosphingolipids, mainly globotriaosylceramide (Gb3). Vascular endothelial cells may play important roles in disease pathogenesis, and are one of the main target cell types in therapeutic interventions. In this study, we generated immortalized aortic endothelial cell lines from a mouse model of Fabry disease. These cells retained endothelial cell-specific markers and functions. Gb3 expression level in one of these clones (referred to as FMEC2) was highly susceptible to culture media, and appeared to be regulated by glucosylceramide synthase. Results also showed that Gb3 could be upregulated by hydrocortisone. FMEC2 express the mannose 6-phosphate receptor and sortilin but not the mannose receptor. Uptake studies suggested that sortilin plays a role in the binding and internalization of mammalian cell-produced α-galactosidase A. Moss-aGal (a plant-made enzyme) was endocytosed by FMEC2 via a receptor other than the aforementioned receptors. In conclusion, this study suggests that glucosylceramide synthase and hydrocortisone may play important roles in modulating Gb3 levels in Fabry mouse aortic endothelial cells, and that endocytosis of recombinant α-galactosidase A involves a combination of multiple receptors depending on the properties of the enzyme. PMID:26960552

  10. Endothelial Outgrowth Cells: Function and Performance in Vascular Grafts

    PubMed Central

    Glynn, Jeremy J.

    2014-01-01

    The clinical need for vascular grafts continues to grow. Tissue engineering strategies have been employed to develop vascular grafts for patients lacking sufficient autologous vessels for grafting. Restoring a functional endothelium on the graft lumen has been shown to greatly improve the long-term patency of small-diameter grafts. However, obtaining an autologous source of endothelial cells for in vitro endothelialization is invasive and often not a viable option. Endothelial outgrowth cells (EOCs), derived from circulating progenitor cells in peripheral blood, provide an alternative cell source for engineering an autologous endothelium. This review aims at highlighting the role of EOCs in the regulation of processes that are central to vascular graft performance. To characterize EOC performance in vascular grafts, this review identifies the characteristics of EOCs, defines functional performance criteria for EOCs in vascular grafts, and summarizes the existing work in developing vascular grafts with EOCs. PMID:24004404

  11. Dynamic Endothelial Cell Rearrangements Drive Developmental Vessel Regression

    PubMed Central

    Franco, Claudio A.; Jones, Martin L.; Bernabeu, Miguel O.; Geudens, Ilse; Mathivet, Thomas; Rosa, Andre; Lopes, Felicia M.; Lima, Aida P.; Ragab, Anan; Collins, Russell T.; Phng, Li-Kun; Coveney, Peter V.; Gerhardt, Holger

    2015-01-01

    Patterning of functional blood vessel networks is achieved by pruning of superfluous connections. The cellular and molecular principles of vessel regression are poorly understood. Here we show that regression is mediated by dynamic and polarized migration of endothelial cells, representing anastomosis in reverse. Establishing and analyzing the first axial polarity map of all endothelial cells in a remodeling vascular network, we propose that balanced movement of cells maintains the primitive plexus under low shear conditions in a metastable dynamic state. We predict that flow-induced polarized migration of endothelial cells breaks symmetry and leads to stabilization of high flow/shear segments and regression of adjacent low flow/shear segments. PMID:25884288

  12. Human neural stem cell-induced endothelial morphogenesis requires autocrine/paracrine and juxtacrine signaling.

    PubMed

    Chou, Chung-Hsing; Modo, Michel

    2016-01-01

    Transplanted neural stem cells (NSC) interact with the host brain microenvironment. A neovascularization is commonly observed in the vicinity of the cell deposit, which is correlated with behavioral improvements. To elucidate the signaling mechanisms between human NSCs and endothelial cells (ECs), these were cocultured in an in vitro model in which NSC-induced endothelial morphogenesis produced a neurovascular environment. Soluble (autocrine/paracrine) and contact-mediated (juxtacrine) signaling molecules were evaluated for two conditionally immortalized fetal NSC lines derived from the cortical anlage (CTXOE03) and ganglionic eminence (STROC05), as well as an adult EC line (D3) derived from the cerebral microvasculature of a hippocampal biopsy. STROC05 were 4 times as efficient to induce endothelial morphogenesis compared to CTXOE03. The cascade of reciprocal interactions between NSCs and ECs in this process was determined by quantifying soluble factors, receptor mapping, and immunocytochemistry for extracellular matrix molecules. The mechanistic significance of these was further evaluated by pharmacological blockade. The sequential cell-specific regulation of autocrine/paracrine and juxtacrine signaling accounted for the differential efficiency of NSCs to induce endothelial morphogenesis. These in vitro studies shed new light on the reciprocal interactions between NSCs and ECs, which are pivotal for our mechanistic understanding of the efficacy of NSC transplantation. PMID:27374240

  13. Human neural stem cell-induced endothelial morphogenesis requires autocrine/paracrine and juxtacrine signaling

    PubMed Central

    Chou, Chung-Hsing; Modo, Michel

    2016-01-01

    Transplanted neural stem cells (NSC) interact with the host brain microenvironment. A neovascularization is commonly observed in the vicinity of the cell deposit, which is correlated with behavioral improvements. To elucidate the signaling mechanisms between human NSCs and endothelial cells (ECs), these were cocultured in an in vitro model in which NSC-induced endothelial morphogenesis produced a neurovascular environment. Soluble (autocrine/paracrine) and contact–mediated (juxtacrine) signaling molecules were evaluated for two conditionally immortalized fetal NSC lines derived from the cortical anlage (CTXOE03) and ganglionic eminence (STROC05), as well as an adult EC line (D3) derived from the cerebral microvasculature of a hippocampal biopsy. STROC05 were 4 times as efficient to induce endothelial morphogenesis compared to CTXOE03. The cascade of reciprocal interactions between NSCs and ECs in this process was determined by quantifying soluble factors, receptor mapping, and immunocytochemistry for extracellular matrix molecules. The mechanistic significance of these was further evaluated by pharmacological blockade. The sequential cell-specific regulation of autocrine/paracrine and juxtacrine signaling accounted for the differential efficiency of NSCs to induce endothelial morphogenesis. These in vitro studies shed new light on the reciprocal interactions between NSCs and ECs, which are pivotal for our mechanistic understanding of the efficacy of NSC transplantation. PMID:27374240

  14. Rapid flow-induced responses in endothelial cells

    NASA Technical Reports Server (NTRS)

    Stamatas, G. N.; McIntire, L. V.

    2001-01-01

    Endothelial cells alter their morphology, growth rate, and metabolism in response to fluid shear stress. To study rapid flow-induced responses in the 3D endothelial cell morphology and calcium distribution, coupled fluorescence microscopy with optical sectioning, digital imaging, and numerical deconvolution techniques have been utilized. Results demonstrate that within the first minutes of flow application nuclear calcium is increasing. In the same time frame whole cell height and nuclear height are reduced by about 1 microm. Whole cell height changes may facilitate reduction of shear stress gradients on the luminal surface, whereas nuclear structural changes may be important for modulating endothelial growth rate and metabolism. To study the role of the cytoskeleton in these responses, endothelial cells have been treated with specific disrupters (acrylamide, cytochalasin D, and colchicine) of each of the cytoskeleton elements (intermediate filaments, microfilaments, and microtubules, respectively). None of these compounds had any effect on the shear-induced calcium response. Cytochalasin D and acrylamide did not affect the shear-induced nuclear morphology changes. Colchicine, however, completely abrogated the response, indicating that microtubules may be implicated in force transmission from the plasma membrane to the nucleus. A pedagogical model based on tensegrity theory principles is presented that is consistent with the results on the 3D endothelial morphology.

  15. Fibroblast nemosis induces angiogenic responses of endothelial cells

    SciTech Connect

    Enzerink, Anna; Rantanen, Ville; Vaheri, Antti

    2010-03-10

    Increasing evidence points to a central link between inflammation and activation of the stroma, especially of fibroblasts therein. However, the mechanisms leading to such activation mostly remain undescribed. We have previously characterized a novel type of fibroblast activation (nemosis) where clustered fibroblasts upregulated the production of cyclooxygenase-2, secretion of prostaglandins, proteinases, chemotactic cytokines, and hepatocyte growth factor (HGF), and displayed activated nuclear factor-{kappa}B. Now we show that nemosis drives angiogenic responses of endothelial cells. In addition to HGF, nemotic fibroblasts secreted vascular endothelial growth factor (VEGF), and conditioned medium from spheroids promoted sprouting and networking of human umbilical venous endothelial cells (HUVEC). The response was partly inhibited by function-blocking antibodies against HGF and VEGF. Conditioned nemotic fibroblast medium promoted closure of HUVEC and human dermal microvascular endothelial cell monolayer wounds, by increasing the motility of the endothelial cells. Wound closure in HUVEC cells was partly inhibited by the antibodies against HGF. The stromal microenvironment regulates wound healing responses and often promotes tumorigenesis. Nemosis offers clues to the activation process of stromal fibroblasts and provides a model to study the part they play in angiogenesis-related conditions, as well as possibilities for therapeutical approaches desiring angiogenesis in tissue.

  16. Human cultured endothelial cells do secrete endothelin-1

    SciTech Connect

    Clozel, M.; Fischli, W. )

    1989-01-01

    Endothelin-1 (ET-1) has been identified in the conditioned medium of porcine endothelial cells. Human endothelin (ET-1) cloned from a placenta cDNA library is similar to porcine, but it is not known whether endothelin itself is secreted by human endothelial cells. To answer this question, a conditioned medium taken every 48 h from confluent cultures of umbilical vein endothelial cells was analyzed by HPLC and all fractions were tested for their ability to inhibit ({sup 125}I)ET-1 binding on human placenta membranes. Only one fraction did inhibit ({sup 125}I)ET-1 binding. When the conditioned medium was spiked with ET-1, the same single fraction inhibited ({sup 125}I)ET-1 binding showing that ET-1, itself, is present in the conditioned medium of human endothelial cells. ET-1 accumulates with time, reaching a plateau at 48 h. ET-1 secretion is not increased by a 24-h incubation of endothelial cells with phorbol myristate acetate, interleukin-1, tumor necrosis factor, thrombin or neuropeptide Y.

  17. Endothelial cells regulate neural crest and second heart field morphogenesis

    PubMed Central

    Milgrom-Hoffman, Michal; Michailovici, Inbal; Ferrara, Napoleone; Zelzer, Elazar; Tzahor, Eldad

    2014-01-01

    ABSTRACT Cardiac and craniofacial developmental programs are intricately linked during early embryogenesis, which is also reflected by a high frequency of birth defects affecting both regions. The molecular nature of the crosstalk between mesoderm and neural crest progenitors and the involvement of endothelial cells within the cardio–craniofacial field are largely unclear. Here we show in the mouse that genetic ablation of vascular endothelial growth factor receptor 2 (Flk1) in the mesoderm results in early embryonic lethality, severe deformation of the cardio–craniofacial field, lack of endothelial cells and a poorly formed vascular system. We provide evidence that endothelial cells are required for migration and survival of cranial neural crest cells and consequently for the deployment of second heart field progenitors into the cardiac outflow tract. Insights into the molecular mechanisms reveal marked reduction in Transforming growth factor beta 1 (Tgfb1) along with changes in the extracellular matrix (ECM) composition. Our collective findings in both mouse and avian models suggest that endothelial cells coordinate cardio–craniofacial morphogenesis, in part via a conserved signaling circuit regulating ECM remodeling by Tgfb1. PMID:24996922

  18. Effects of shear stress on endothelial progenitor cells.

    PubMed

    Obi, Syotaro; Yamamoto, Kimiko; Ando, Joji

    2014-10-01

    Endothelial progenitor cells (EPCs) are adult stem cells that play a central role in neovascularization. EPCs are mobilized from bone marrow into peripheral blood, attach to existing endothelial cells, and then transmigrate across the endothelium into tissues, where they proliferate, differentiate, and form new blood vessels. In the process, EPCs are exposed to shear stress, a biomechanical force generated by flowing blood and tissue fluid flow. When cultured EPCs are exposed to controlled levels of shear stress in a flow-loading device, their bioactivities in terms of proliferation, anti-apoptosis, migration, production of bioactive substances, anti-thrombosis, and tube formation increase markedly. Expression of endothelial marker genes and proteins by EPCs also increases in response to shear stress, and they differentiate into mature endothelial cells. Great advances have been made in elucidating the mechanisms by which mature endothelial cells sense and respond to shear stress, but not in EPCs. Further study of EPC responses to shear stress will be necessary to better understand the physiological and pathophysiological roles of EPCs and to apply EPCs to new therapies in the field of regenerative medicine. PMID:25992410

  19. Biophysical Assessment of Single Cell Cytotoxicity: Diesel Exhaust Particle-Treated Human Aortic Endothelial Cells

    PubMed Central

    Wu, Yangzhe; Yu, Tian; Gilbertson, Timothy A.; Zhou, Anhong; Xu, Hao; Nguyen, Kytai Truong

    2012-01-01

    Exposure to diesel exhaust particles (DEPs), a major source of traffic-related air pollution, has become a serious health concern due to its adverse influences on human health including cardiovascular and respiratory disorders. To elucidate the relationship between biophysical properties (cell topography, cytoskeleton organizations, and cell mechanics) and functions of endothelial cells exposed to DEPs, atomic force microscope (AFM) was applied to analyze the toxic effects of DEPs on a model cell line from human aortic endothelial cells (HAECs). Fluorescence microscopy and flow cytometry were also applied to further explore DEP-induced cytotoxicity in HAECs. Results revealed that DEPs could negatively impair cell viability and alter membrane nanostructures and cytoskeleton components in a dosage- and a time-dependent manner; and analyses suggested that DEPs-induced hyperpolarization in HAECs appeared in a time-dependent manner, implying DEP treatment would lead to vasodilation, which could be supported by down-regulation of cell biophysical properties (e.g., cell elasticity). These findings are consistent with the conclusion that DEP exposure triggers important biochemical and biophysical changes that would negatively impact the pathological development of cardiovascular diseases. For example, DEP intervention would be one cause of vasodilation, which will expand understanding of biophysical aspects associated with DEP cytotoxicity in HAECs. PMID:22662129

  20. TRPV4 channels mediate cyclic strain-induced endothelial cell reorientation through integrin to integrin signaling

    PubMed Central

    Thodeti, Charles K.; Matthews, Benjamin; Ravi, Arvind; Mammoto, Akiko; Ghosh, Kaustabh; Bracha, Abigail L.; Ingber, Donald E.

    2009-01-01

    Cyclic mechanical strain produced by pulsatile blood flow regulates the orientation of endothelial cells lining blood vessels, and influences critical processes such as angiogenesis. Mechanical stimulation of stretch-activated calcium channels is known to mediate this reorientation response, however, the molecular basis remains unknown. Here we show that cyclically stretching capillary endothelial cells adherent to flexible extracellular matrix substrates activates mechanosensitive TRPV4 ion channels that, in turn, stimulate phosphatidyl inositol-3-kinase-dependent activation and binding of additional ·1 integrin receptors, which promotes cytoskeletal remodeling and cell reorientation. Inhibition of integrin activation using blocking antibodies and knockdown of TRPV4 channels using specific siRNA suppress strain-induced capillary cell reorientation. Thus, mechanical forces that physically deform extracellular matrix may guide capillary cell reorientation through a strain-dependent ‘integrin to integrin’ signaling mechanism mediated by force-induced activation of mechanically-gated TRPV4 ion channels on the cell surface. PMID:19359599

  1. Arsenite promotes apoptosis and dysfunction in microvascular endothelial cells via an alteration of intracellular calcium homeostasis.

    PubMed

    Suriyo, Tawit; Watcharasit, Piyajit; Thiantanawat, Apinya; Satayavivad, Jutamaad

    2012-04-01

    Vascular endothelium has been considered as a target for arsenic-induced cardiovascular toxicity. The present study demonstrated that arsenite caused slow and sustained elevation of intracellular free calcium levels ([Ca2+]i) in HMEC-1, a human microvessel-derived endothelial cell line, in a concentration-dependent manner. Pretreatment with U-73122 (a specific PLC inhibitor) or 2-APB (a specific IP3 receptor antagonist) attenuated this effect, suggesting that PLC/IP3 signaling cascade is involved in arsenite-induced elevation of [Ca2+]i. Cytotoxic concentrations of arsenite (5 and 10 μM) significantly enhanced endothelial nitric oxide synthase (eNOS) phosphorylation, nitric oxide (NO) production and apoptosis after 24-h exposure. Additionally, 2-APB attenuated eNOS phosphorylation and apoptosis induced by arsenite, indicating that Ca2+ -mediated eNOS activation participates in arsenite-induced endothelial cell apoptosis. Moreover, we also found that non-apoptotic concentrations of arsenite (0.5 and 1 μM) dramatically mitigated thrombin-induced rapid transient rise of [Ca2+]i, eNOS phosphorylation and NO production, suggesting functional disruption of endothelial by arsenite, and these effects occurred without an alteration of PLC-β1 and thrombin receptor levels. Altogether, the results reveal that arsenite induces apoptotic cell death and endothelial dysfunction as indicated by the reduction of thrombin responses, particularly related to an alteration of intracellular Ca2+ homeostasis. PMID:22244921

  2. Endothelial Cells Stimulate Self-Renewal and Expand Neurogenesis of Neural Stem Cells

    NASA Astrophysics Data System (ADS)

    Shen, Qin; Goderie, Susan K.; Jin, Li; Karanth, Nithin; Sun, Yu; Abramova, Natalia; Vincent, Peter; Pumiglia, Kevin; Temple, Sally

    2004-05-01

    Neural stem cells are reported to lie in a vascular niche, but there is no direct evidence for a functional relationship between the stem cells and blood vessel component cells. We show that endothelial cells but not vascular smooth muscle cells release soluble factors that stimulate the self-renewal of neural stem cells, inhibit their differentiation, and enhance their neuron production. Both embryonic and adult neural stem cells respond, allowing extensive production of both projection neuron and interneuron types in vitro. Endothelial coculture stimulates neuroepithelial cell contact, activating Notch and Hes1 to promote self-renewal. These findings identify endothelial cells as a critical component of the neural stem cell niche.

  3. Infection of hepatitis B virus in extrahepatic endothelial tissues mediated by endothelial progenitor cells

    PubMed Central

    Rong, Qifei; Huang, Jun; Su, Enben; Li, Jun; Li, Jianyong; Zhang, Lili; Cao, Kejiang

    2007-01-01

    Background Hepatitis B virus (HBV) replication has been reported to be involved in many extrahepatic viral disorders; however, the mechanism by which HBV is trans-infected into extrahepatic tissues such as HBV associated myocarditis remains largely unknown. Results In this study, we showed that human cord blood endothelial progenitor cells (EPCs), but not human umbilical vein endothelial cells (HUVECs) could be effectively infected by uptake of HBV in vitro. Exposure of EPCs with HBV resulted in HBV DNA and viral particles were detected in EPCs at day 3 after HBV challenge, which were peaked around day 7 and declined in 3 weeks. Consistently, HBV envelope surface and core antigens were first detected in EPCs at day 3 after virus challenge and were retained to be detectable for 3 weeks. In contrast, HBV covalently closed circular DNA was not detected in EPCs at any time after virus challenge. Intravenous transplantation of HBV-treated EPCs into myocardial infarction and acute renal ischemia mouse model resulted in incorporation of HBV into injured heart, lung, and renal capillary endothelial tissues. Conclusion These results strongly support that EPCs serve as virus carrier mediating HBV trans-infection into the injured endothelial tissues. The findings might provide a novel mechanism for HBV-associated myocarditis and other HBV-related extrahepatic diseases as well. PMID:17407553

  4. Targeting brain microvascular endothelial cells: a therapeutic approach to neuroprotection against stroke

    PubMed Central

    Yu, Qi-jin; Tao, Hong; Wang, Xin; Li, Ming-chang

    2015-01-01

    Brain microvascular endothelial cells form the interface between nervous tissue and circulating blood, and regulate central nervous system homeostasis. Brain microvascular endothelial cells differ from peripheral endothelial cells with regards expression of specific ion transporters and receptors, and contain fewer fenestrations and pinocytotic vesicles. Brain microvascular endothelial cells also synthesize several factors that influence blood vessel function. This review describes the morphological characteristics and functions of brain microvascular endothelial cells, and summarizes current knowledge regarding changes in brain microvascular endothelial cells during stroke progression and therapies. Future studies should focus on identifying mechanisms underlying such changes and developing possible neuroprotective therapeutic interventions. PMID:26807131

  5. Global cell-by-cell evaluation of endothelial viability after two methods of graft preparation in Descemet membrane endothelial keratoplasty

    PubMed Central

    Bhogal, Maninder; Balda, Maria S; Matter, Karl; Allan, Bruce D

    2016-01-01

    Purpose To describe a novel method of global cell viability assessment for Descemet membrane endothelial keratoplasty (DMEK) and the comparison of two contemporary methods of donor tissue preparation. Methods DMEK transplants were prepared using two different methods: liquid bubble separation and manual peeling (n=8 each group). Samples were incubated with Hoechst, calcein-AM and ethidium homodimer prior to mounting on a curved imaging chamber. Z-stacked fluorescence microscopy images were combined to produce an in-focus global image capable of resolving all cell nuclei. Image processing software was used to define a calcein-positive live cell area, count all cell nuclei within this area and subtract ethidium-positive dead cells to derive the total viable endothelial cell count. Corrected global cell density was calculated by dividing the number of viable cells by the graft area, which had been corrected for imaging a curved surface. Results Corrected global cell density was lower than the central endothelial cell density in both groups: 85.5% of the pre-preparation central endothelial cell density in the peel group and 75.8% in the bubble group. Corrected global cell density was significantly lower in the liquid bubble separation group than in the peel group (p=0.04). Conclusions Eye bank estimations of central endothelial cell density overestimate true cell density after graft preparation in DMEK. A peel method is less damaging and more consistent than a liquid bubble method. Cell loss correlated strongly with the degree of stromal hydration prior to bubble separation in the liquid bubble group. PMID:26740609

  6. Neuroprotective effects of systemic cerebral endothelial cell transplantation in a rat model of cerebral ischemia

    PubMed Central

    Moon, Jong-Hyun; Na, Joo-Young; Lee, Min-Cheol; Choi, Kang-Ho; Lee, Jeong-Kil; Min, Jung-Joon; Kim, Kyung-Tae; Park, Jong-Tae; Park, Man-Seok; Kim, Hyung-Seok

    2016-01-01

    Human cerebral microvascular endothelial cell line (hCMEC)/D3 cells, which are from a stable clonal cell line of human immortalized cerebral endothelial cells, were intra-arterially transplanted through the common carotid artery in a rat model of photochemical-induced cerebral ischemia. Their therapeutic effects on infarct size, blood-brain barrier (BBB) breakdown, and outcome were examined. The hCMEC/D3 cells were genetically modified with the firefly luciferase gene for in vivo imaging post-transplantation. Transplanted hCMEC/D3 cells were identified in the infarcted brain by bioluminescence imaging at 1 day after transplantation. Compared with the control group, the hCMEC/D3-transplanted group showed reduced infarct size on day 3, reduced Evans blue dye leakage on day 1 indicating decreased BBB breakdown, and early recovery from Rotarod test neurological deficits. The hCMEC/D3-transplanted group also showed decreased levels of matrix metalloproteinase (MMP)-9, which were inversely correlated with TIMP-1 levels on post-transplantation days 1 and 3. The expression of tumor necrosis factor-α and interleukin-1β were markedly diminished in the hCMEC/D3-transplanted group compared with controls. The systemically transplanted cells selectively migrated and integrated into the ischemically lesioned area, which accelerated neurological recovery. This new cerebral endothelial cell-based therapy may hold promise for clinical trials in patients with ischemic stroke. PMID:27347342

  7. Neuroprotective effects of systemic cerebral endothelial cell transplantation in a rat model of cerebral ischemia.

    PubMed

    Moon, Jong-Hyun; Na, Joo-Young; Lee, Min-Cheol; Choi, Kang-Ho; Lee, Jeong-Kil; Min, Jung-Joon; Kim, Kyung-Tae; Park, Jong-Tae; Park, Man-Seok; Kim, Hyung-Seok

    2016-01-01

    Human cerebral microvascular endothelial cell line (hCMEC)/D3 cells, which are from a stable clonal cell line of human immortalized cerebral endothelial cells, were intra-arterially transplanted through the common carotid artery in a rat model of photochemical-induced cerebral ischemia. Their therapeutic effects on infarct size, blood-brain barrier (BBB) breakdown, and outcome were examined. The hCMEC/D3 cells were genetically modified with the firefly luciferase gene for in vivo imaging post-transplantation. Transplanted hCMEC/D3 cells were identified in the infarcted brain by bioluminescence imaging at 1 day after transplantation. Compared with the control group, the hCMEC/D3-transplanted group showed reduced infarct size on day 3, reduced Evans blue dye leakage on day 1 indicating decreased BBB breakdown, and early recovery from Rotarod test neurological deficits. The hCMEC/D3-transplanted group also showed decreased levels of matrix metalloproteinase (MMP)-9, which were inversely correlated with TIMP-1 levels on post-transplantation days 1 and 3. The expression of tumor necrosis factor-α and interleukin-1β were markedly diminished in the hCMEC/D3-transplanted group compared with controls. The systemically transplanted cells selectively migrated and integrated into the ischemically lesioned area, which accelerated neurological recovery. This new cerebral endothelial cell-based therapy may hold promise for clinical trials in patients with ischemic stroke. PMID:27347342

  8. Directed endothelial cell morphogenesis in micropatterned gelatin methacrylate hydrogels.

    PubMed

    Nikkhah, Mehdi; Eshak, Nouran; Zorlutuna, Pinar; Annabi, Nasim; Castello, Marco; Kim, Keekyoung; Dolatshahi-Pirouz, Alireza; Edalat, Faramarz; Bae, Hojae; Yang, Yunzhi; Khademhosseini, Ali

    2012-12-01

    Engineering of organized vasculature is a crucial step in the development of functional and clinically relevant tissue constructs. A number of previous techniques have been proposed to spatially regulate the distribution of angiogenic biomolecules and vascular cells within biomaterial matrices to promote vascularization. Most of these approaches have been limited to two-dimensional (2D) micropatterned features or have resulted in formation of random vasculature within three-dimensional (3D) microenvironments. In this study, we investigate 3D endothelial cord formation within micropatterned gelatin methacrylate (GelMA) hydrogels with varying geometrical features (50-150 μm height). We demonstrated the significant dependence of endothelial cells proliferation, alignment and cord formation on geometrical dimensions of the patterned features. The cells were able to align and organize within the micropatterned constructs and assemble to form cord structures with organized actin fibers and circular/elliptical cross-sections. The inner layer of the cord structure was filled with gel showing that the micropatterned hydrogel constructs guided the assembly of endothelial cells into cord structures. Notably, the endothelial cords were retained within the hydrogel microconstructs for all geometries after two weeks of culture; however, only the 100 μm-high constructs provided the optimal microenvironment for the formation of circular and stable cord structures. Our findings suggest that endothelial cord formation is a preceding step to tubulogenesis and the proposed system can be used to develop organized vasculature for engineered tissue constructs. PMID:23018132

  9. Directed Endothelial Cell Morphogenesis in Micropatterned Gelatin Methacrylate Hydrogels

    PubMed Central

    Nikkhah, Mehdi; Eshak, Nouran; Zorlutuna, Pinar; Annabi, Nasim; Castello, Marco; Kim, Keekyoung; Dolatshahi-Pirouz, Alireza; Edalat, Faramarz; Bae, Hojae; Yang, Yunzhi; Khademhosseini, Ali

    2013-01-01

    Engineering of organized vasculature is a crucial step in the development of functional and clinically relevant tissue constructs. A number of previous techniques have been proposed to spatially regulate the distribution of angiogenic biomolecules and vascular cells within biomaterial matrices to promote vascularization. Most of these approaches have been limited to two-dimensional (2D) micropatterned features or have resulted in formation of random vasculature within three-dimensional (3D) microenvironments. In this study, we investigate 3D endothelial cord formation within micropatterned gelatin methacrylate (GelMA) hydrogels with varying geometrical features (50–150 µm height). We demonstrated the significance dependence of endothelial cells proliferation, alignment and cord formation on geometrical dimensions of the patterned features. The cells were able to align and organize within the micropatterned constructs and assemble to form cord structures with organized actin fibers and circular/elliptical cross-sections. The inner layer of the cord structure was filled with gel showing that the micropatterned hydrogel constructs guided the assembly of endothelial cells into cord structures. Notably, the endothelial cords were retained within the hydrogel microconstructs for all geometries after two weeks of culture; however, only the 100 µm-high constructs provided the optimal microenvironment for the formation of circular and stable cord structures. Our findings suggest that endothelial cord formation is a preceding step to tubulogenesis and the proposed system can be used to develop organized vasculature for engineered tissue constructs. PMID:23018132

  10. Irradiation enhances the support of haemopoietic cell transmigration, proliferation and differentiation by endothelial cells.

    PubMed

    Gaugler, M H; Squiban, C; Mouthon, M A; Gourmelon, P; van der Meeren, A

    2001-06-01

    Endothelial cells (ECs) are a critical component of the bone marrow stroma in the regulation of haemopoiesis. Recovery of bone marrow aplasia after radiation exposure depends, in part, on the repair of radiation-induced endothelial damage. Therefore, we assessed the ability of an irradiated human bone marrow EC line (TrHBMEC) to support transmigration, proliferation and differentiation of CD34+ bone marrow cells either irradiated or not in transendothelial migration or co-culture models. Radiation-induced EC damage was reflected by an increased release of soluble intercellular adhesion molecule (sICAM)-1 and platelet endothelial cell adhesion molecule (PECAM)-1. Irradiation of TrHBMECs with a 10 Gy dose strongly enhanced the transmigration of CD34+ cells, granulo-monocytic progenitors (CFU-GM) and erythroid progenitors (BFU-E). While ICAM-1 and PECAM-1 expression on irradiated TrHBMECs was increased, only antibodies against PECAM-1 inhibited the radiation-induced enhanced transmigration of haemopoietic cells. Irradiation of TrHBMECs (5-15 Gy) also increased proliferation and differentiation towards the granulo-monocytic lineage of co-cultured CD34+ cells, as well as colony formation by those cells and the production of interleukin 6 (IL-6), IL-8, granulocyte colony-stimulating factor (CSF) and granulocyte-macrophage CSF. Irradiated TrHBMECs were more capable of stimulating irradiated (1,2 Gy) CD34+ cells and haemopoietic progenitors than non-irradiated TrHBMECs. Together, these results suggest that, despite the radiation-induced damage, irradiated ECs may favour haemopoietic reconstitution after radiation exposure. PMID:11442488

  11. Isolation of endothelial cells from human placental microvessels: effect of different proteolytic enzymes on releasing endothelial cells from villous tissue.

    PubMed

    Ugele, B; Lange, F

    2001-01-01

    Approaches for the isolation of human placental microvascular endothelial cells (HPMEC) using proteolytic enzymes have been described recently. However, the isolation procedure and enzyme composition most suitable for optimal disaggregation of placental tissue and isolation of HPMEC has not yet been established. We tested different proteolytic enzymes and enzyme mixtures for their capabilities of releasing endothelial cells from human term placental villous tissue. Best results were obtained with a mixture of collagenase/dispase/deoxyribonuclease I (0.28%/0.25%/0.01%). By adding a discontinuous Percoll gradient centrifugation step to the enzymatic dispersion, about 1 x 10(6) cells/g tissue with more than 30% von Willebrand factor (vWf)-positive cells were obtained. However, the total cell number and number of vWf-positive cells were highly dependent on the lot of collagenase used. A perfusion step prior to mincing of villous tissue did not increase the amount of vWf-positive cells. We conclude that the methods described in this study are suitable to isolate high yields of HPMEC and that the composition of the collagenase preparation is crucial to the successful release of endothelial cells from placental tissue. To obtain pure HPMEC, further separation steps, e.g., cell sorting with antibodies against endothelial specific cell surface antigens are necessary. PMID:11573814

  12. Cerebral capillary endothelial cells are covered by the VEGF-expressing foot processes of astrocytes.

    PubMed

    Saito, Tomomi; Shibasaki, Koji; Kurachi, Masashi; Puentes, Sandra; Mikuni, Masahiko; Ishizaki, Yasuki

    2011-06-22

    Molecules that have crucial functions in both nervous and vascular systems have attracted keen attention recently, and the name "angioneurins" has been proposed. The most striking example of angioneurins is vascular endothelial growth factor A (VEGF), which was originally identified as a key regulator of angiogenesis and has only recently been found to have important functions in the nervous system. In this study, we compared VEGF expression in the vasculature in the brain with that in the aorta and the vasculature in the kidney in mice. In larger vessels containing smooth muscle cells, VEGF was expressed by smooth muscle cells covering the lining of endothelial cells, both in and outside the brain. In cerebral capillaries lacking smooth muscle cells, endothelial cells were closely covered by VEGF-expressing foot processes of astrocytes, whereas capillaries were surrounded by VEGF-expressing processes of podocytes in the renal glomeruli. We also found that cultured cerebral microvessel endothelial cells do not express VEGF, whereas cultured cortical astrocytes do express VEGF. PMID:21536099

  13. Risk factors, endothelial cell turnover and lipid transport in atherogenesis.

    PubMed

    Lin, S J

    1996-11-01

    Cardiovascular diseases remain to be the 4th rank of top ten causes of mortality in Taiwan in recent years. Atherosclerosis and coronary artery disease, which often culminating in the occurrence of myocardial infarction and congestive heart failure, are responsible for the majority of these death. One of the prominent features of atherosclerotic lesion is local accumulation of lipids, mainly in the forms of cholesteryl ester and free cholesterol, either within cells or extracellularly in matrix. Repeated endothelial injury and enhanced lipid infiltration are critical events in the development of atherosclerosis. Plasma lipoproteins may enter the arterial wall through endothelium, either transcellularly via vesicular transport or paracellularly via intercellular junction. Our previous studies have demonstrated that most of the arterial endothelial cells in mitosis are associated with the leakage of fluorescently labeled albumin and low density lipoproteins. Subsequently, such transendothelial leakage of macromolecules is also shown to be associated with endothelial cell death as assessed by immunocytochemical staining for IgG. These findings suggested that transiently leaky junctions occurring during endothelial cell turnover may provide potentially important pathways for increasing transport or leakage of macromolecules, including atherogenic LDL, across the vascular endothelium. Electron microscopic study using horseradish peroxidase as a tracer revealed markedly widening of intercellular junctions around endothelial cells in mitosis providing direct evidence in support of "cell turnover-leaky junction" theory for the localization of atherogenesis. Hypertension, smoking, diabetes, and hyperlipidemia are well-known major risk factors for atherosclerosis and coronary heart disease. In a series of investigations, we examined the hypothesis that hypertension smoking, diabetes, and hyperlipidemia increase the arterial endothelial cell turnover and hence

  14. Endothelial progenitor cells and burn injury - exploring the relationship.

    PubMed

    Banyard, Derek A; Adnani, Blake O; Melkumyan, Satenik; Araniego, Cheryl Ann; Widgerow, Alan D

    2016-01-01

    Burn wounds result in varying degrees of soft tissue damage that are typically graded clinically. Recently a key participant in neovascularization, the endothelial progenitor cell, has been the subject of intense cardiovascular research to explore whether it can serve as a biomarker for vascular injury. In this review, we examine the identity of the endothelial progenitor cell as well as the evidence that support its role as a key responder after burn insult. While there is conflicting evidence with regards to the delta of endothelial progenitor cell mobilization and burn severity, it is clear that they play an important role in wound healing. Systematic and controlled studies are needed to clarify this relationship, and whether this population can serve as a biomarker for burn severity. PMID:27574674

  15. Interaction between Endothelial Protein C Receptor and Intercellular Adhesion Molecule 1 to Mediate Binding of Plasmodium falciparum-Infected Erythrocytes to Endothelial Cells

    PubMed Central

    Avril, Marion; Bernabeu, Maria; Benjamin, Maxwell; Brazier, Andrew Jay

    2016-01-01

    ABSTRACT Intercellular adhesion molecule 1 (ICAM-1) and the endothelial protein C receptor (EPCR) are candidate receptors for the deadly complication cerebral malaria. However, it remains unclear if Plasmodium falciparum parasites with dual binding specificity are involved in cytoadhesion or different parasite subpopulations bind in brain microvessels. Here, we investigated this issue by studying different subtypes of ICAM-1-binding parasite lines. We show that two parasite lines expressing domain cassette 13 (DC13) of the P. falciparum erythrocyte membrane protein 1 (PfEMP1) family have dual binding specificity for EPCR and ICAM-1 and further mapped ICAM-1 binding to the first DBLβ domain following the PfEMP1 head structure in both proteins. As PfEMP1 head structures have diverged between group A (EPCR binders) and groups B and C (CD36 binders), we also investigated how ICAM-1-binding parasites with different coreceptor binding traits influence P. falciparum-infected erythrocyte binding to endothelial cells. Whereas levels of binding to tumor necrosis factor alpha (TNF-α)-stimulated endothelial cells from the lung and brain by all ICAM-1-binding parasite lines increased, group A (EPCR and ICAM-1) was less dependent than group B (CD36 and ICAM-1) on ICAM-1 upregulation. Furthermore, both group A DC13 parasite lines had higher binding levels to brain endothelial cells (a microvascular niche with limited CD36 expression). This study shows that ICAM-1 is a coreceptor for a subset of EPCR-binding parasites and provides the first evidence of how EPCR and ICAM-1 interact to mediate parasite binding to both resting and TNF-α-activated primary brain and lung endothelial cells. PMID:27406562

  16. Endothelial Cells Enhance Tumor Cell Invasion through a Crosstalk Mediated by CXC Chemokine Signaling1

    PubMed Central

    Warner, Kristy A; Miyazawa, Marta; Cordeiro, Mabel M R; Love, William J; Pinsky, Matthew S; Neiva, Kathleen G; Spalding, Aaron C; Nör, Jacques E

    2008-01-01

    Field cancerization involves the lateral spread of premalignant or malignant disease and contributes to the recurrence of head and neck tumors. The overall hypothesis underlying this work is that endothelial cells actively participate in tumor cell invasion by secreting chemokines and creating a chemotactic gradient for tumor cells. Here we demonstrate that conditioned medium from head and neck tumor cells enhance Bcl-2 expression in neovascular endothelial cells. Oral squamous cell carcinoma-3 (OSCC3) and Kaposi's sarcoma (SLK) show enhanced invasiveness when cocultured with pools of human dermal microvascular endothelial cells stably expressing Bcl-2 (HDMEC-Bcl-2), compared to cocultures with empty vector controls (HDMEC-LXSN). Xenografted OSCC3 tumors vascularized with HDMEC-Bcl-2 presented higher local invasion than OSCC3 tumors vascularized with control HDMEC-LXSN. CXCL1 and CXCL8 were upregulated in primary endothelial cells exposed to vascular endothelial growth factor (VEGF), as well as in HDMEC-Bcl-2. Notably, blockade of CXCR2 signaling, but not CXCR1, inhibited OSCC3 and SLK invasion toward endothelial cells. These data demonstrate that CXC chemokines secreted by endothelial cells induce tumor cell invasion and suggest that the process of lateral spread of tumor cells observed in field cancerization is guided by chemotactic signals that originated from endothelial cells. PMID:18283335

  17. Identification of the endothelial cell binding site for factor IX.

    PubMed Central

    Cheung, W F; van den Born, J; Kühn, K; Kjellén, L; Hudson, B G; Stafford, D W

    1996-01-01

    We previously demonstrated that the primary region of factor IX and IXa responsible for saturable specific binding to bovine aortic endothelial cells resides in residues 3-11 at the amino terminus of factor IX. We also demonstrated that mutations of lysine to alanine at residue 5, factor IX K5A, or valine to lysine at residue 10, factor IX V10K, resulted in a molecule unable to bind to endothelial cells. Moreover, a mutation with lysine to arginine at residue 5, factor IX K5R, resulted in a factor IX molecule with increased affinity for the endothelial cell binding site. In this paper we report that collagen IV is a strong candidate for the factor IX binding site on endothelial cells. Factor IX and factor IX K5R compete with 125I-labeled factor IX for binding to tetrameric collagen IV immobilized on microtiter plates, while factor X, factor VII, and factor IX K5A or V10K fail to compete. The Kd for wild-type factor IX binding to collagen IV in the presence of heparin was 6.8 +/- 2 nM, and the Kd for factor IX K5R was 1.1 +/- 0.2 nM, which agrees well with our previously published Kd values of 7.4 and 2.4 nM for binding of the same proteins to endothelial cells. Our working assumption is that we have identified the endothelial cell binding site and that it is collagen IV. Its physiological relevance remains to be determined. PMID:8855310

  18. Von Willebrand factor regulates complement on endothelial cells.

    PubMed

    Noone, Damien G; Riedl, Magdalena; Pluthero, Fred G; Bowman, Mackenzie L; Liszewski, M Kathryn; Lu, Lily; Quan, Yi; Balgobin, Steve; Schneppenheim, Reinhard; Schneppenheim, Sonja; Budde, Ulrich; James, Paula; Atkinson, John P; Palaniyar, Nades; Kahr, Walter H A; Licht, Christoph

    2016-07-01

    Atypical hemolytic uremic syndrome and thrombotic thrombocytopenic purpura have traditionally been considered separate entities. Defects in the regulation of the complement alternative pathway occur in atypical hemolytic uremic syndrome, and defects in the cleavage of von Willebrand factor (VWF)-multimers arise in thrombotic thrombocytopenic purpura. However, recent studies suggest that both entities are related as defects in the disease-causing pathways overlap or show functional interactions. Here we investigate the possible functional link of VWF-multimers and the complement system on endothelial cells. Blood outgrowth endothelial cells (BOECs) were obtained from 3 healthy individuals and 2 patients with Type 3 von Willebrand disease lacking VWF. Cells were exposed to a standardized complement challenge via the combination of classical and alternative pathway activation and 50% normal human serum resulting in complement fixation to the endothelial surface. Under these conditions we found the expected release of VWF-multimers causing platelet adhesion onto BOECs from healthy individuals. Importantly, in BOECs derived from patients with von Willebrand disease complement C3c deposition and cytotoxicity were more pronounced than on BOECs derived from normal individuals. This is of particular importance as primary glomerular endothelial cells display a heterogeneous expression pattern of VWF with overall reduced VWF abundance. Thus, our results support a mechanistic link between VWF-multimers and the complement system. However, our findings also identify VWF as a new complement regulator on vascular endothelial cells and suggest that VWF has a protective effect on endothelial cells and complement-mediated injury. PMID:27236750

  19. Treponema pallidum Invades Intercellular Junctions of Endothelial Cell Monolayers

    NASA Astrophysics Data System (ADS)

    Thomas, D. Denee; Navab, Mahamad; Haake, David A.; Fogelman, Alan M.; Miller, James N.; Lovett, Michael A.

    1988-05-01

    The pathogenesis of syphilis reflects invasive properties of Treponema pallidum, but the actual mode of tissue invasion is unknown. We have found two in vitro parallels of treponemal invasiveness. We tested whether motile T. pallidum could invade host cells by determining the fate of radiolabeled motile organisms added to a HeLa cell monolayer; 26% of treponemes associated with the monolayer in a trypsin-resistant niche, presumably between the monolayer and the surface to which it adhered, but did not attain intracellularity. Attachment of T. pallidum to cultured human and rabbit aortic and human umbilical vein endothelial cells was 2-fold greater than to HeLa cells. We added T. pallidum to aortic endothelial cells grown on membrane filters under conditions in which tight intercellular junctions had formed. T. pallidum was able to pass through the endothelial cell monolayers without altering tight junctions, as measured by electrical resistance. In contrast, heat-killed T. pallidum and the nonpathogen Treponema phagedenis biotype Reiter failed to penetrate the monolayer. Transmission electron micrographs of sections of the monolayer showed T. pallidum in intercellular junctions. Our in vitro observations suggest that these highly motile spirochetes may leave the circulation by invading the junctions between endothelial cells.

  20. New insights in endothelial and smooth muscle cell communication.

    PubMed

    Conejo, Víctor Arana; De Haro, Roberto; Sosa-Melgarejo, Jorge; Méndez, José D

    2007-01-01

    Based on immunohistochemical techniques against connexins and the intercellular flux of staining molecules, it has previously been shown that electrotonic communication occurs among endothelial and vascular smooth muscle cells, this due to the presence of myoendothelial gap junctions. The aim of this study was to evaluate the density of myoendothelial contacts in the left coronary and internal mammary arteries as well as in the left saphenous vein by means of electron microscopy, the distance between both cells participating in an myoendothelial contact with a semi-automatic image analysis system and the presence of homocellular and heterocellular gap junctions between endothelial and smooth muscle cells by using the immunohistochemical technique and confocal microscopy in thoracic aorta were also analyzed. The results are that all blood vessels studied present myoendothelial contacts, while density studies show that they are more abundant in the saphenous vein. The myoendothelial contact distance is constant and in no case the cytoplasmic processes reach the plasma membrane of the partner cell toward which they are advanced. Homocellular gap junctions were found between smooth muscle cells and between endothelial cells. Heterocellular gap junctions were absent, evidencing the possibility that signaling molecules between endothelial and smooth muscle cells may be transferred through plasma membranes as was once thought and not necessarily by electrotonic communication. PMID:17383847

  1. Molecular response of liver sinusoidal endothelial cells on hydrogels.

    PubMed

    Bartneck, Matthias; Topuz, Fuat; Tag, Carmen Gabriele; Sauer-Lehnen, Sibille; Warzecha, Klaudia Theresa; Trautwein, Christian; Weiskirchen, Ralf; Tacke, Frank

    2015-06-01

    There is a high demand for the isolation of primary endothelial cells for biomaterial endotheliazation studies, tissue engineering, and artificial organ development. Further, biomarkers for monitoring the response of endothelial cells in biomaterials science are required. We systematically compared two strategies for isolating liver sinusoidal endothelial cells (LSEC) from mouse liver. We demonstrate that fluorescence-activated cell sorting results in a considerably higher purity (~97%) compared to magnetic-assisted cell sorting (~80%), but is associated with a lower yield and recovery rate. Cell repellent polyethylene glycol (PEG) substrates affected the morphology of primary LSEC in culture and significantly downregulated the intracellular adhesion molecule (ICAM) and upregulated the vascular cell adhesion molecule (VCAM). This molecular response could partially be reverted by further modification with arginylglycylaspartic acid (RGD). Thus, usage of PEGylated materials may reduce, while applying RGD may support endotheliazation of materials, and we could relate LSEC attachment to their expression of ICAM and VCAM mRNA, suggesting their usage as biomarkers for endothelialization. PMID:25842109

  2. Neutrophil Elastase-Generated Fragment of Vascular Endothelial Growth Factor-A Stimulates Macrophage and Endothelial Progenitor Cell Migration

    PubMed Central

    Kurtagic, Elma; Rich, Celeste B.; Buczek-Thomas, Jo Ann; Nugent, Matthew A.

    2015-01-01

    Elastase released from neutrophils as part of the innate immune system has been implicated in chronic diseases such as emphysema and cardiovascular disease. We have previously shown that neutrophil elastase targets vascular endothelial growth factor-A (VEGF) for partial degradation to generate a fragment of VEGF (VEGFf) that has distinct activities. Namely, VEGFf binds to VEGF receptor 1 but not to VEGF receptor 2 and shows altered signaling compared to intact VEGF. In the present study we investigated the chemotactic function of VEGF and VEGFf released from cells by neutrophil elastase. We found that endothelial cells migrated in response to intact VEGF but not VEGFf whereas RAW 264.7 macrophages/monocytes and embryonic endothelial progenitor cells were stimulated to migrate by either VEGF or VEGFf. To investigate the role of elastase-mediated release of VEGF from cells/extracellular matrices, a co-culture system was established. High or low VEGF producing cells were co-cultured with macrophages, endothelial or endothelial progenitor cells and treated with neutrophil elastase. Elastase treatment stimulated macrophage and endothelial progenitor cell migration with the response being greater with the high VEGF expressing cells. However, elastase treatment led to decreased endothelial cell migration due to VEGF cleavage to VEGF fragment. These findings suggest that the tissue response to NE-mediated injury might involve the generation of diffusible VEGF fragments that stimulate inflammatory cell recruitment. PMID:26672607

  3. Lymphatic endothelial cells are a replicative niche for Mycobacterium tuberculosis

    PubMed Central

    Lerner, Thomas R.; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Russell, Matthew R.G.; Borel, Sophie; Diedrich, Collin R.; Rohde, Manfred; Wainwright, Helen; Collinson, Lucy M.; Wilkinson, Robert J.; Griffiths, Gareth; Gutierrez, Maximiliano G.

    2016-01-01

    In extrapulmonary tuberculosis, the most common site of infection is within the lymphatic system, and there is growing recognition that lymphatic endothelial cells (LECs) are involved in immune function. Here, we identified LECs, which line the lymphatic vessels, as a niche for Mycobacterium tuberculosis in the lymph nodes of patients with tuberculosis. In cultured primary human LECs (hLECs), we determined that M. tuberculosis replicates both in the cytosol and within autophagosomes, but the bacteria failed to replicate when the virulence locus RD1 was deleted. Activation by IFN-γ induced a cell-autonomous response in hLECs via autophagy and NO production that restricted M. tuberculosis growth. Thus, depending on the activation status of LECs, autophagy can both promote and restrict replication. Together, these findings reveal a previously unrecognized role for hLECs and autophagy in tuberculosis pathogenesis and suggest that hLECs are a potential niche for M. tuberculosis that allows establishment of persistent infection in lymph nodes. PMID:26901813

  4. Lymphatic endothelial cells are a replicative niche for Mycobacterium tuberculosis.

    PubMed

    Lerner, Thomas R; de Souza Carvalho-Wodarz, Cristiane; Repnik, Urska; Russell, Matthew R G; Borel, Sophie; Diedrich, Collin R; Rohde, Manfred; Wainwright, Helen; Collinson, Lucy M; Wilkinson, Robert J; Griffiths, Gareth; Gutierrez, Maximiliano G

    2016-03-01

    In extrapulmonary tuberculosis, the most common site of infection is within the lymphatic system, and there is growing recognition that lymphatic endothelial cells (LECs) are involved in immune function. Here, we identified LECs, which line the lymphatic vessels, as a niche for Mycobacterium tuberculosis in the lymph nodes of patients with tuberculosis. In cultured primary human LECs (hLECs), we determined that M. tuberculosis replicates both in the cytosol and within autophagosomes, but the bacteria failed to replicate when the virulence locus RD1 was deleted. Activation by IFN-γ induced a cell-autonomous response in hLECs via autophagy and NO production that restricted M. tuberculosis growth. Thus, depending on the activation status of LECs, autophagy can both promote and restrict replication. Together, these findings reveal a previously unrecognized role for hLECs and autophagy in tuberculosis pathogenesis and suggest that hLECs are a potential niche for M. tuberculosis that allows establishment of persistent infection in lymph nodes. PMID:26901813

  5. A mesoderm-derived precursor for mesenchymal stem and endothelial cells

    PubMed Central

    Vodyanik, Maxim A.; Yu, Junying; Zhang, Xin; Tian, Shulan; Stewart, Ron; Thomson, James A.; Slukvin, Igor I.

    2010-01-01

    Summary Among the three embryonic germ layers, the mesoderm is a major source of the mesenchymal precursors giving rise to skeletal and connective tissues. These precursors, however, have not been previously identified and characterized. Using human embryonic stem cells directed to mesendodermal differentiation, here we show that mesenchymal stem/stromal cells (MSCs) originate from a population of mesodermal cells identified by expression of the apelin receptor. In semisolid medium, these precursors form FGF2-dependent compact spheroid colonies containing mesenchymal cells with a transcriptional profile representative of mesoderm-derived embryonic mesenchyme. When transferred to the adherent cultures, individual colonies give rise to MSC lines with chondro-, osteo-, and adipogenenic differentiation potentials. Although the MSC lines lacked endothelial potential, endothelial cells could be derived from mesenchymal colonies, suggesting that, similar to hematopoietic cells, MSCs arise from precursors with angiogenic potential. Together, these studies identified a common precursor of mesenchymal and endothelial cells, mesenchymoangioblast, as the source of mesoderm-derived MSCs. PMID:21112566

  6. Human Endothelial Cells: Use of Heparin in Cloning and Long-Term Serial Cultivation

    NASA Astrophysics Data System (ADS)

    Thornton, Susan C.; Mueller, Stephen N.; Levine, Elliot M.

    1983-11-01

    Endothelial cells from human blood vessels were cultured in vitro, with doubling times of 17 to 21 hours for 42 to 79 population doublings. Cloned human endothelial cell strains were established for the first time and had similar proliferative capacities. This vigorous cell growth was achieved by addition of heparin to culture medium containing reduced concentrations of endothelial cell growth factor. The routine cloning and long-term culture of human endothelial cells will facilitate studying the human endothelium in vitro.

  7. [Isolation of endothelial cells from human umbilical cords and development of low-cost culture medium].

    PubMed

    Karasaki, Y

    1996-12-01

    To study the role of endothelial cells in important biological phenomena such as thrombosis and atherosclerosis, it is necessary to have a sufficient amount of endothelial cells. This report shows modified methods to isolate endothelial cells from the human umbilical vein and the components of potent and low-cost culture medium for the cells. PMID:8981651

  8. When the endothelium scores an own goal: endothelial cells actively augment metastatic extravasation through endothelial-mesenchymal transition.

    PubMed

    Gasparics, Ákos; Rosivall, László; Krizbai, István A; Sebe, Attila

    2016-05-01

    Endothelial-mesenchymal transition (EndMT) is an important mechanism during organ development and in certain pathological conditions. For example, EndMT contributes to myofibroblast formation during organ fibrosis, and it has been identified as an important source of cancer-associated fibroblasts, facilitating tumor progression. Recently, EndMT was proposed to modulate endothelial function during intravasation and extravasation of metastatic tumor cells. Evidence suggests that endothelial cells are not passive actors during transendothelial migration (TEM) of cancer cells, as there are profound changes in endothelial junctional protein expression, signaling, permeability, and contractility. This review describes these alterations in endothelial characteristics during TEM of metastatic tumor cells and discusses them in the context of EndMT. EndMT could play an important role during metastatic intravasation and extravasation, a novel hypothesis that may lead to new therapeutic approaches to tackle metastatic disease. PMID:26993222

  9. Spatiotemporal analysis of RhoA/B/C activation in primary human endothelial cells

    PubMed Central

    Reinhard, Nathalie R.; van Helden, Suzanne F.; Anthony, Eloise C.; Yin, Taofei; Wu, Yi I.; Goedhart, Joachim; Gadella, Theodorus W. J.; Hordijk, Peter L.

    2016-01-01

    Endothelial cells line the vasculature and are important for the regulation of blood pressure, vascular permeability, clotting and transendothelial migration of leukocytes and tumor cells. A group of proteins that that control the endothelial barrier function are the RhoGTPases. This study focuses on three homologous (>88%) RhoGTPases: RhoA, RhoB, RhoC of which RhoB and RhoC have been poorly characterized. Using a RhoGTPase mRNA expression analysis we identified RhoC as the highest expressed in primary human endothelial cells. Based on an existing RhoA FRET sensor we developed new RhoB/C FRET sensors to characterize their spatiotemporal activation properties. We found all these RhoGTPase sensors to respond to physiologically relevant agonists (e.g. Thrombin), reaching transient, localized FRET ratio changes up to 200%. These RhoA/B/C FRET sensors show localized GEF and GAP activity and reveal spatial activation differences between RhoA/C and RhoB. Finally, we used these sensors to monitor GEF-specific differential activation of RhoA/B/C. In summary, this study adds high-contrast RhoB/C FRET sensors to the currently available FRET sensor toolkit and uncover new insights in endothelial and RhoGTPase cell biology. This allows us to study activation and signaling by these closely related RhoGTPases with high spatiotemporal resolution in primary human cells. PMID:27147504

  10. Spatiotemporal analysis of RhoA/B/C activation in primary human endothelial cells.

    PubMed

    Reinhard, Nathalie R; van Helden, Suzanne F; Anthony, Eloise C; Yin, Taofei; Wu, Yi I; Goedhart, Joachim; Gadella, Theodorus W J; Hordijk, Peter L

    2016-01-01

    Endothelial cells line the vasculature and are important for the regulation of blood pressure, vascular permeability, clotting and transendothelial migration of leukocytes and tumor cells. A group of proteins that that control the endothelial barrier function are the RhoGTPases. This study focuses on three homologous (>88%) RhoGTPases: RhoA, RhoB, RhoC of which RhoB and RhoC have been poorly characterized. Using a RhoGTPase mRNA expression analysis we identified RhoC as the highest expressed in primary human endothelial cells. Based on an existing RhoA FRET sensor we developed new RhoB/C FRET sensors to characterize their spatiotemporal activation properties. We found all these RhoGTPase sensors to respond to physiologically relevant agonists (e.g. Thrombin), reaching transient, localized FRET ratio changes up to 200%. These RhoA/B/C FRET sensors show localized GEF and GAP activity and reveal spatial activation differences between RhoA/C and RhoB. Finally, we used these sensors to monitor GEF-specific differential activation of RhoA/B/C. In summary, this study adds high-contrast RhoB/C FRET sensors to the currently available FRET sensor toolkit and uncover new insights in endothelial and RhoGTPase cell biology. This allows us to study activation and signaling by these closely related RhoGTPases with high spatiotemporal resolution in primary human cells. PMID:27147504

  11. Insulin-like growth factor-I modulates monocyte adhesion to EAhy 926 endothelial cells

    PubMed Central

    MOTANI, ALYKHAN; FORSTER, LOUISE; TULL, SAMANTHA; ÄNGGÅRD, ERIK E.; FERNS, GORDON A.A.

    1996-01-01

    IGF-I is a ubiquitous growth factor, found in platelets and elaborated by many other cell types. It is thought to be involved in several pathophysiological processes including embryonic development, angiogenesis and wound healing. We report that the adherence of human peripheral blood monocytes to an endothelial cell line (EAhy 926) is inhibited in a dose and time-dependent manner by pre-incubating the endothelial cells with IGF-I (P < 0.001). Monocyte adhesion was inhibited 17.9 ± 1.9% by IGF-I at a dose of 1000 ng/ml (P < 0.01). In contrast, IGF-I had no significant effect on monocyte adherence to plastic. The inhibitory effects of IGF-I were reversed by co-incubating the endothelial cells with the nitric oxide synthase inhibitor, L-NAME. These data suggest that the effects of IGF-I are mediated by the release of nitric oxide from the endothelial cells. PMID:8664144

  12. Insulin-like growth factor-I modulates monocyte adhesion to EAhy 926 endothelial cells.

    PubMed

    Motani, A; Forster, L; Tull, S; Anggård, E E; Ferns, G A

    1996-02-01

    IGF-I is a ubiquitous growth factor, found in platelets and elaborated by many other cell types. It is thought to be involved in several pathophysiological processes including embryonic development, angiogenesis and wound healing. We report that the adherence of human peripheral blood monocytes to an endothelial cell line (EAhy 926) is inhibited in a dose and time-dependent manner by pre-incubating the endothelial cells with IGF-I (P < 0.001). Monocyte adhesion was inhibited 17.9 +/- 1.9% by IGF-I at a dose of 1000 ng/ml (P < 0.01). In contrast, IGF-I had no significant effect on monocyte adherence to plastic. The inhibitory effects of IGF-I were reversed by co-incubating the endothelial cells with the nitric oxide synthase inhibitor, L-NAME. These data suggest that the effects of IGF-I are mediated by the release of nitric oxide from the endothelial cells. PMID:8664144

  13. Effects of irradiated biodegradable polymer in endothelial cell monolayer formation

    NASA Astrophysics Data System (ADS)

    Arbeitman, Claudia R.; del Grosso, Mariela F.; Behar, Moni; García Bermúdez, Gerardo

    2013-11-01

    In this work we study cell adhesion, proliferation and cell morphology of endothelial cell cultured on poly-L-lactide acid (PLLA) modified by heavy ion irradiation. Thin films of PLLA samples were irradiated with sulfur (S) at energies of 75 MeV and gold (Au) at 18 MeV ion-beams. Ion beams were provided by the Tandar (Buenos Aires, Argentina) and Tandetron (Porto Alegre, Brazil) accelerators, respectively. The growth of a monolayer of bovine aortic endothelial cells (BAEC) onto unirradiated and irradiated surfaces has been studied by in vitro techniques in static culture. Cell viability and proliferation increased on modified substrates. But the results on unirradiated samples, indicate cell death (necrosis/apoptosis) with the consequent decrease in proliferation. We analyzed the correlation between irradiation parameters and cell metabolism and morphology.

  14. Caveolae, Caveolins, Cavins, and Endothelial Cell Function: New Insights

    PubMed Central

    Sowa, Grzegorz

    2012-01-01

    Caveolae are cholesterol and glycosphingolipid-rich flask-shaped invaginations of the plasma membrane which are particularly abundant in vascular endothelium and present in all other cell types of the cardiovascular system, including vascular smooth-muscle cells, macrophages, cardiac myocytes, and fibroblasts. Caveolins and the more recently discovered cavins are the major protein components of caveolae. When caveolae were discovered, their functional role was believed to be limited to transport across the endothelial cell barrier. Since then, however, a large body of evidence has accumulated, suggesting that these microdomains are very important in regulating many other important endothelial cell functions, mostly due to their ability to concentrate and compartmentalize various signaling molecules. Over the course of several years, multiple studies involving knockout mouse and small interfering RNA approaches have considerably enhanced our understanding of the role of caveolae and caveolin-1 in regulating many cardiovascular functions. New findings have been reported implicating other caveolar protein components in endothelial cell signaling and function, such as the understudied caveolin-2 and newly discovered cavin proteins. The aim of this review is to focus primarily on molecular and cellular aspects of the role of caveolae, caveolins, and cavins in endothelial cell signaling and function. In addition, where appropriate, the possible implications for the cardiovascular and pulmonary physiology and pathophysiology will be discussed. PMID:22232608

  15. Zinc and dexamethasone induce metallothionein accumulation by endothelial cells

    SciTech Connect

    Briske-Anderson, M.; Bobilya, D.J.; Reeves, P.G. )

    1991-03-11

    Several tissues increase their metallothionein (MT) concentration when exposed to elevated amounts of plasma Zn. Endothelial cells form the blood vessels that supply all tissues and constitute a barrier between cells of tissues and the blood. This study examined the ability of endothelial cells to synthesize MT and accumulate Zn in response to high amounts of Zn and dexamethasone. Bovine pulmonary endothelial cells were grown to confluence in Minimum Essential Medium with Earle's salts and 10% fetal calf serum. The monolayer was maintained for 2 d prior to use in medium containing EDTA-dialyzed serum. This low Zn medium was replaced with one containing 1, 6, 25, 50, 100, 150, or 200 {mu}M Zn and incubated for 24 hr before harvesting the cells. MT was quantified by the cadmium binding assay. Cellular Zn concentrations were analyzed by atomic absorption after a nitric acid digestion. The MT concentration was elevated in response to Zn concentrations of 100 {mu}M or more. Cellular Zn concentration was elevated when media Zn was 25 {mu}M or more. MT and cellular Zn concentrations were positively correlated. In another study, inclusion of 0.1 {mu}M dexamethasone in the media increased concentration at all Zn concentrations studied. However, the inclusion of 0.3 {mu}M cis-platinum had no effect. In conclusion, endothelial cells in culture respond to elevated amounts of Zn and dexamethasone in the media by accumulating Zn and MT.

  16. Serglycin in Quiescent and Proliferating Primary Endothelial Cells

    PubMed Central

    Reine, Trine M.; Vuong, Tram T.; Rutkovskiy, Arkady; Meen, Astri J.; Vaage, Jarle; Jenssen, Trond G.; Kolset, Svein O.

    2015-01-01

    Proteoglycans are fundamental components of the endothelial barrier, but the functions of the proteoglycan serglycin in endothelium are less described. Our aim was to describe the roles of serglycin in processes relevant for endothelial dysfunction. Primary human umbilical vein endothelial cells (HUVEC) were cultured in vitro and the expression of proteoglycans was investigated. Dense cell cultures representing the quiescent endothelium coating the vasculature was compared to sparse activated cell cultures, relevant for diabetes, cancer and cardiovascular disease. Secretion of 35S- proteoglycans increased in sparse cultures, and we showed that serglycin is a major component of the cell-density sensitive proteoglycan population. In contrast to the other proteoglycans, serglycin expression and secretion was higher in proliferating compared to quiescent HUVEC. RNAi silencing of serglycin inhibited proliferation and wound healing, and serglycin expression and secretion was augmented by hypoxia, mechanical strain and IL-1β induced inflammation. Notably, the secretion of the angiogenic chemokine CCL2 resulting from IL-1β activation, was increased in serglycin knockdown cells, while angiopoietin was not affected. Both serglycin and CCL2 were secreted predominantly to the apical side of polarized HUVEC, and serglycin and CCL2 co-localized both in perinuclear areas and in vesicles. These results suggest functions for serglycin in endothelial cells trough interactions with partner molecules, in biological processes with relevance for diabetic complications, cardiovascular disease and cancer development. PMID:26694746

  17. Tumor endothelial cells with distinct patterns of TGFβ-driven endothelial-to-mesenchymal transition

    PubMed Central

    Xiao, Lin; Kim, Dae Joong; Davis, Clayton L.; McCann, James V.; Dunleavey, James M.; Vanderlinden, Alissa; Xu, Nuo; Pattenden, Samantha G.; Frye, Stephen V.; Xu, Xia; Onaitis, Mark; Monaghan-Benson, Elizabeth; Burridge, Keith; Dudley, Andrew C.

    2015-01-01

    Endothelial-to-mesenchymal transition (EndMT) occurs during development and underlies the pathophysiology of multiple diseases. In tumors, unscheduled EndMT generates cancer-associated myofibroblasts that fuel inflammation and fibrosis, and may contribute to vascular dysfunction that promotes tumor progression. We report that freshly isolated subpopulations of tumor-specific endothelial cells (TEC) from a spontaneous mammary tumor model undergo distinct forms of EndMT in response to TGFβ stimulation. Whereas some TEC strikingly up-regulate alpha smooth muscle actin (SMA), a principal marker of EndMT and activated myofibroblasts, counterpart normal mammary gland endothelial cells (NEC) showed little change in SMA expression after TGFβ treatment. Compared with NEC, SMA+ TEC were 40 % less motile in wound healing assays and formed more stable vascular-like networks in vitro when challenged with TGFβ. Lineage tracing using ZsGreenCdh5-Cre reporter mice confirmed that only a fraction of vessels in breast tumors contain SMA+ TEC, suggesting that not all endothelial cells (EC) respond identically to TGFβ in vivo. Indeed, examination of 84 TGFβ-regulated target genes revealed entirely different genetic signatures in TGFβ-stimulated NEC and TEC cultures. Finally, we found that basic FGF (bFGF) exerts potent inhibitory effects on many TGFβ-regulated genes but operates in tandem with TGFβ to up-regulate others. EC challenged with TGFβ secrete bFGF which blocks SMA expression in secondary cultures suggesting a cell-autonomous or lateral-inhibitory mechanism for impeding mesenchymal differentiation. Together, our results suggest that TGFβ-driven EndMT produces a spectrum of EC phenotypes with different functions that could underlie the plasticity and heterogeneity of the tumor vasculature. PMID:25634211

  18. Effects of physical activity on endothelial progenitor cells (EPCs)

    PubMed Central

    De Biase, Chiara; De Rosa, Roberta; Luciano, Rossella; De Luca, Stefania; Capuano, Ernesto; Trimarco, Bruno; Galasso, Gennaro

    2014-01-01

    Physical activity has a therapeutic role in cardiovascular disease (CVD), through its beneficial effects on endothelial function and cardiovascular system. Circulating endothelial progenitor cells (EPCs) are bone marrow (BM) derived cells that represent a novel therapeutic target in CVD patients, because of their ability to home to sites of ischemic injury and repair the damaged vessels. Several studies show that physical activity results in a significant increase in circulating EPCs, and, in particular, there are some evidence of the beneficial exercise-induced effects on EPCs activity in CVD settings, including coronary artery disease (CAD), heart failure (HF), and peripheral artery disease (PAD). The aim of this paper is to review the current evidence about the beneficial effects of physical exercise on endothelial function and EPCs levels and activity in both healthy subjects and patients with CVD. PMID:24550833

  19. [Isolation, culture and identification of human umbilical vein endothelial cells].

    PubMed

    Chen, Xiaocui; Chen, Bangdang; Yang, Yining; Zhou, Yun; Liu, Fen; Gai, Mintao; Chen, Qingjie; Ma, Yitong

    2016-03-01

    Objective To establish a simple, reliable and efficient isolation and culture method of human umbilical vein endothelial cells (HUVECs) in vitro. Methods Type 2 collagenase was used to digest umbilical cord and separate HUVECs. The cells were cultured in the endothelial cell culture medium (ECM). The cell morphology was observed under an inverted phase-contrast microscope. Immunofluorescence technique was applied to detect the expression of von Willebrand factor (vWF). Cell purity was determined by detecting CD31 level on cell surface with flow cytometry. Tube formation assay was used to test the function of the endothelial cells after cryopreservation in vitro. Results HUVECs successfully isolated were proved with high purity and good activity. HUVECs of primary generation could merge into a single layer one week after isolation. The cells showed a typical cobblestone-like arrangement. Immunofluorescence technique validated that the cells could widely express vWF and the expression frequency of CD31 was 93.1%. The cells were still capable of forming the lumen structure after cryopreservation, indicating that the standardized cryopreservation method could well maintain the cell function. Conclusion This is a simple, reliable and efficient method of isolating and culturing HUVECs in vitro. PMID:26927551

  20. Modulation of Human Vascular Endothelial Cell Behaviors by Nanotopographic Cues

    PubMed Central

    Liliensiek, S.J.; Wood, J.A.; Yong, J.; Auerbach, R.; Nealey, P.F.; Murphy, C.J.

    2010-01-01

    Basement membranes possess a complex three dimensional topography in the nanoscale and submicron range which have been shown to profoundly modulate a large menu of fundamental cell behaviors. Using the topographic features found in native vascular endothelial basement membranes as a guide, polyurethane substrates were fabricated containing anisotropically ordered ridge and groove structures and isotropically ordered pores from 200 nm to 2000 nm in size. We investigated the impact of biomimetic length-scale topographic cues on orientation/elongation, proliferation and migration on four human vascular endothelial cell-types from large and small diameter vessels. We found that all cell-types exhibited orientation and alignment with the most pronounced response on anisotropically ordered ridges ≥ 800 nm. HUVEC cells were the only cell-type examined to demonstrate a decrease in proliferation in response to the smallest topographic features regardless of surface order. On anisotropically ordered surfaces all cell types migrated preferentially parallel to the long axis of the ridges, with the greatest increase in cell migration being observed on the 1200 nm pitch. In contrast, cells did not exhibit any preference in direction or increase in migration speed on isotropically ordered surfaces. Overall, our data demonstrate that surface topographic features impact vascular endothelial cell behavior and that the impact of features varies with the cell behavior being considered, topographic feature scale, surface order, and the anatomic origin of the cell being investigated. PMID:20400175

  1. Modulation of human vascular endothelial cell behaviors by nanotopographic cues.

    PubMed

    Liliensiek, Sara J; Wood, Joshua A; Yong, Jiang; Auerbach, Robert; Nealey, Paul F; Murphy, Christopher J

    2010-07-01

    Basement membranes possess a complex three-dimensional topography in the nanoscale and submicron range which have been shown to profoundly modulate a large menu of fundamental cell behaviors. Using the topographic features found in native vascular endothelial basement membranes as a guide, polyurethane substrates were fabricated containing anisotropically ordered ridge and groove structures and isotropically ordered pores from 200 nm to 2000 nm in size. We investigated the impact of biomimetic length-scale topographic cues on orientation/elongation, proliferation and migration on four human vascular endothelial cell-types from large and small diameter vessels. We found that all cell-types exhibited orientation and alignment with the most pronounced response on anisotropically ordered ridges > or =800 nm. HUVEC cells were the only cell-type examined to demonstrate a decrease in proliferation in response to the smallest topographic features regardless of surface order. On anisotropically ordered surfaces all cell-types migrated preferentially parallel to the long axis of the ridges, with the greatest increase in cell migration being observed on the 1200 nm pitch. In contrast, cells did not exhibit any preference in direction or increase in migration speed on isotropically ordered surfaces. Overall, our data demonstrate that surface topographic features impact vascular endothelial cell behavior and that the impact of features varies with the cell behavior being considered, topographic feature scale, surface order, and the anatomic origin of the cell being investigated. PMID:20400175

  2. HYPOCHLORITE-SERUM REACTION PRODUCTS INHIBIT PORCINE VASCULAR ENDOTHELIAL CELL GROWTH IN CULTURE

    EPA Science Inventory

    In vitro toxicity studies were initiated in order to determine if chlorination affects vascular endothelial cells. Twelfth to twentieth passage porcine aortic vascular endothelial cells (PAE) were grown to confluency and replated in the presence of complete media (Eagle's minimum...

  3. Improved endothelialization of titanium vascular implants by extracellular matrix secreted from endothelial cells.

    PubMed

    Tu, Qiufen; Zhao, Yuancong; Xue, Xiaoqing; Wang, Jin; Huang, Nan

    2010-12-01

    A variety of metals have been widely used in construction of cardiovascular implants (CVIs), such as artificial heart valves, ventricular pumps, and vascular stents. Although great effects have been put into rigorous anticoagulation, late thrombosis still occurred due to inferior blood and cell compatibility. Natural endothelium is popularly regarded as the only substance that has long-term anticoagulant ability. So, establishment of a compact endothelial cell (EC) monolayer on CVIs surface is a guarantee for their long-term potency. In the work described here, titanium (Ti) disks were coated with extracellular matrix (ECM) directly secreted by human umbilical vein endothelial cells (HUVECs), so as to help ECs proliferate and migrate and to improve their endothelialization in vivo. Deposition of ECM on Ti disks was detected by immunofluorescence microscopy, diffuse reflectance Fourier transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. The surface topography and wettability of the Ti disks significantly changed after ECM deposition. Most importantly, it was found that ECM deposition inhibited platelet adhesion, stimulated EC proliferation, increased EC migration speed in vitro, and eventually accelerated the re-cellularization speed of Ti disks in vivo. These important results render it reasonable and feasible to modify CVIs with ECM secreted from ECs for improving their long-term potency. PMID:20666613

  4. Regulation of human endothelial progenitor cell maturation by polyurethane nanocomposites.

    PubMed

    Hung, Huey-Shan; Yang, Yi-Chun; Lin, Yu-Chun; Lin, Shinn-Zong; Kao, Wei-Chien; Hsieh, Hsien-Hsu; Chu, Mei-Yun; Fu, Ru-Huei; Hsu, Shan-hui

    2014-08-01

    The mobilization and homing of endothelial progenitor cells (EPCs) are critical to the development of an antithrombotic cardiovascular prosthesis. Polyurethane (PU) with superior elasticity may provide a mechanical environment resembling that of the natural vascular tissues. The topographical cues of PU were maximized by making nanocomposites with a small amount of gold nanoparticles (AuNPs). The nanocomposites of PU-AuNPs ("PU-Au") with a favorable response of endothelial cells were previously established. In the current study, the effect of PU and PU-Au nanocomposites on the behavior of human peripheral blood EPCs was investigated in vitro and in vivo. It was found that PU-Au promoted EPCs to become differentiated endothelial cells in vitro, confirmed by the increased expressions of CD31 and VEGF-R2 surface markers. The increased maturation of EPCs was significantly more remarkable on PU-Au, probably through the stromal derived factor 1α (SDF-1α)/CXCR4 signaling pathway. In vivo experiments showed that EPCs seeded on PU-Au coated catheters effectively reduced thrombosis by differentiation into endothelial cells. Surface endothelialization with CD31 and CD34 expression as well as intimal formation with α-SMA expression was significantly accelerated in the group receiving EPC-seeded PU-Au catheters. Moreover, the analysis of collagen deposition revealed a reduction of fibrosis in the group receiving EPC-seeded PU-Au catheters as compared to the other groups. These results suggest that EPCs engineered with a proper elastic substrate may provide unique endothelialization and antithrombogenic properties that benefit vascular tissue regeneration. PMID:24836305

  5. Binding of ATGs to Endothelial Cells In Vivo.

    PubMed

    Beiras-Fernandez, Andres; Hernandez-Sierra, Astrid; Schulz, Uwe; Richter, Manfred; Thein, Eckart; Moritz, Anton; Werner, Isabella

    2016-01-01

    BACKGROUND Polyclonal anti-thymocyte globulins (ATGs) are immunosuppressive drugs widely used in induction of immunosuppression and treatment of acute rejection after solid organ transplantation. We have previously demonstrated that ATGs bind to endothelial cells in vitro, and are able to modulate ECs. The aim of this study was to investigate the binding of ATGs to endothelial cells under in vivo conditions. MATERIAL AND METHODS Muscle biopsies from extremities of cynomolgus monkeys were obtained after ischemia/reperfusion at 4°C. ATGs (Thymoglobulin, Sanofi-Aventis, France; 1 mg/kg) were added to the blood 30 min prior to the reperfusion. Biopsies (n=10) of patients undergoing heart transplantation and preoperatively treated with ATGs (Thymoglobulin, Sanofi-Aventis, France; 1.5 mg/kg) as induction therapy were also analyzed 6 hours and 7 days after induction. Binding of ATGs to ECs was analyzed with an anti-rabbit IgG antibody by means of immunohistochemistry. RESULTS Binding of ATGs to endothelial cells could be demonstrated in vivo in our animal experiments 4 hours after reperfusion, as well as in the clinical biopsies 6 hours after induction of immunosuppression in heart transplant patients, showing a preferred localization in post-capillary veins. No expression of ATGs on the endothelial surface could be observed after 7 days, suggesting that ATGs may be washed out from the endothelial surface in a time-dependent manner. CONCLUSIONS Our results show that ATGs are able to bind to endothelial cells in an experimental model and in clinical practice, supporting preconditioning strategies with ATGs in solid organ transplantation. PMID:27184761

  6. Glycated serum albumin stimulates expression of endothelial cell specific molecule-1 in human umbilical vein endothelial cells: Implication in diabetes mediated endothelial dysfunction.

    PubMed

    Nirala, Bikesh K; Perumal, Vivekanandan; Gohil, Nivedita K

    2015-07-01

    Pro-inflammatory conditions induced by products of protein glycation in diabetes substantially enhance the risk of endothelial dysfunction and related vascular complications. Endothelial cell specific molecule-1 (ESM-1) or endocan has been demonstrated as a potential biomarker in cancer and sepsis. Its role in diabetes-induced pathologies remains unknown. The expression of ESM-1 gene is under cytokine regulation, indicating its role in endothelium-dependent pathological disorders. In this study, we investigated the effect of advanced glycated human serum albumin (AGE-HSA) on the production of ESM-1. We show that AGE-HSA exerts a modulating role on the expression of ESM-1 in human umbilical vein endothelial cells. It up-regulates expression of ESM-1 protein in a dose-dependent manner which correlates with its messenger RNA (mRNA) transcription. RAGE and galectin-3, both AGE receptors, show antagonistic action on its expression. While gene silencing of RAGE has down-regulatory effect, that of galectin-3 has up-regulatory effect on AGE-induced expression of ESM-1. Inhibition of MAPKKK and JNK pathways did not alter the expression. In contrast, phosphatidylinositol 3 kinase (PI3K) inhibition significantly up-regulated ESM-1 expression. In conclusion, these results suggest that AGE-induced activation of human umbilical vein endothelial cells promotes formation of endocan which is an endothelial dysfunction marker and may be related to vascular disease in diabetes. PMID:25963575

  7. Biomechanical changes in endothelial cells result from an inflammatory response

    NASA Astrophysics Data System (ADS)

    Vaitkus, Janina; Stroka, Kimberly; Aranda-Espinoza, Helim

    2012-02-01

    During periods of infection and disease, the immune system induces the release of TNF-α, an inflammatory cytokine, from a variety of cell types, such as macrophages. TNF-α, while circulating in the vasculature, binds to the apical surface of endothelial cells and causes a wide range of biological and mechanical changes to the endothelium. While the biological changes have been widely studied, the biomechanical aspects have been largely unexplored. Here, we investigated the biomechanical changes of the endothelium as a function of TNF-α treatment. First, we studied the traction forces applied by the endothelium, an effect that is much less studied than others. Through the use of traction force microscopy, we found that TNF-α causes an increase in traction forces applied by the endothelial cells as compared to non-treated cells. Then, we investigated cell morphology, cell mechanics, migration, and cytoskeletal dynamics. We found that in addition to increasing applied traction forces, TNF-α causes an increase in cell area and aspect ratio on average, as well as a shift in the organization of F-actin filaments within the cell. Combining these findings together, our results show that an inflammatory response heavily impacts the morphology, cell mechanics, migration, cytoskeletal dynamics, and applied traction forces of endothelial cells.

  8. Greater osteoblast and endothelial cell adhesion on nanostructured polyethylene and titanium

    PubMed Central

    Raimondo, Theresa; Puckett, Sabrina; Webster, Thomas J

    2010-01-01

    Mostly due to desirable mechanical properties (such as high durability and low wear), certain synthetic polymers (such as polyethylene) and metals (such as titanium) have found numerous applications in the medical device arena from orthopedics to the vasculature, yet frequently, they do not proactively encourage desirable cell responses. In an effort to improve the efficacy of such traditional materials for various implant applications, this study used electron beam evaporation to create nanostructured surface features that mimic those of natural tissue on polyethylene and titanium. For other materials, it has been shown that the creation of nanorough surfaces increases surface energy leading to greater select protein (such as vitronectin and fibronectin) interactions to increase specific cell adhesion. Here, osteoblast (bone forming cells) and endothelial cell (cells that line the vasculature) adhesion was determined on nanostructured compared to conventional, nano-smooth polyethylene and titanium. Results demonstrated that nanorough surfaces created by electron beam evaporation increased the adhesion of both cells markedly better than conventional smooth surfaces. In summary, this study provided evidence that electron beam evaporation can modify implant surfaces (specifically, polyethylene and titanium) to have nanostructured surface features to improve osteoblast and endothelial cell adhesion. Since the adhesion of anchorage dependent cells (such as osteoblasts and endothelial cells) is a prerequisite for their long-term functions, this study suggests that electron beam evaporation should be further studied for improving materials for various biomedical applications. PMID:20856840

  9. Preferential transfer of mitochondria from endothelial to cancer cells through tunneling nanotubes modulates chemoresistance.

    PubMed

    Pasquier, Jennifer; Guerrouahen, Bella S; Al Thawadi, Hamda; Ghiabi, Pegah; Maleki, Mahtab; Abu-Kaoud, Nadine; Jacob, Arthur; Mirshahi, Massoud; Galas, Ludovic; Rafii, Shahin; Le Foll, Frank; Rafii, Arash

    2013-01-01

    Our vision of cancer has changed during the past decades. Indeed tumors are now perceived as complex entities where tumoral and stromal components interact closely. Among the different elements of tumor stroma the cellular component play a primordial role. Bone Marrow derived mesenchymal cells (MSCs) are attracted to tumor sites and support tumor growth. Endothelial cells (ECs) play a major role in angiogenesis. While the literature documents many aspects of the cross talk between stromal and cancer cells, the role of direct hetero-cellular contact is not clearly established. Recently, Tunneling nanotubes (TnTs) have been shown to support cell-to-cell transfers of plasma membrane components, cytosolic molecules and organelles within cell lines. Herein, we have investigated the formation of heterocellular TnTs between stromal (MSCs and ECs) and cancer cells. We demonstrate that TnTs occur between different cancer cells, stromal cells and cancer-stromal cell lines. We showed that TnTs-like structure occurred in 3D anchorage independent spheroids and also in tumor explant cultures. In our culture condition, TnTs formation occurred after large membrane adhesion. We showed that intercellular transfers of cytoplasmic content occurred similarly between cancer cells and MSCs or ECs, but we highlighted that the exchange of mitochondria occurred preferentially between endothelial cells and cancer cells. We illustrated that the cancer cells acquiring mitochondria displayed chemoresistance. Our results illustrate the perfusion-independent role of the endothelium by showing a direct endothelial to cancer cell mitochondrial exchange associated to phenotypic modulation. This supports another role of the endothelium in the constitution of the metastatic niche. PMID:23574623

  10. Cell-Type-Specific Characteristics Modulate the Transduction Efficiency of Adeno-Associated Virus Type 2 and Restrain Infection of Endothelial Cells

    PubMed Central

    Pajusola, Katri; Gruchala, Marcin; Joch, Hana; Lüscher, Thomas F.; Ylä-Herttuala, Seppo; Büeler, Hansruedi

    2002-01-01

    Adeno-associated viruses (AAVs) are promising vectors for various gene therapy applications due to their long-lasting transgene expression and wide spectrum of target cells. Recently, however, it has become apparent that there are considerable differences in the efficiencies of transduction of different cell types by AAVs. Here, we analyzed the efficiencies of transduction and the transport mechanisms of AAV type 2 (AAV-2) in different cell types, emphasizing endothelial cells. Expression analyses in both cultured cells and the rabbit carotid artery assay showed a remarkably low level of endothelial cell transduction in comparison to the highly permissive cell types. The study of the endosomal pathways of AAV-2 with fluorescently labeled virus showed clear targeting of the Golgi area in permissive cell lines, but this phenomenon was absent in the endothelial cell line EAhy-926. On the other hand, the response to the block of endosomal acidification by bafilomycin A1 also showed differences among the permissive cell types. We also analyzed the effect of proteasome inhibitors on endothelial cells, but their impact on the primary cells and in vivo was not significant. On the contrary, analysis of the expression pattern of heparan sulfate proteoglycans (HSPGs), the primary receptors of AAV-2, revealed massive deposits of HSPG in the extracellular matrix of endothelial cells. The matrix-associated receptors may therefore compete for virus binding and reduce transduction in endothelial cells. Accordingly, in endothelial cells detached from their matrix, AAV-2 transduction was significantly increased. Altogether, these results point to a more complex cell-type-specific mode of transduction of AAV-2 than previously appreciated. PMID:12388714

  11. Cell-type-specific characteristics modulate the transduction efficiency of adeno-associated virus type 2 and restrain infection of endothelial cells.

    PubMed

    Pajusola, Katri; Gruchala, Marcin; Joch, Hana; Lüscher, Thomas F; Ylä-Herttuala, Seppo; Büeler, Hansruedi

    2002-11-01

    Adeno-associated viruses (AAVs) are promising vectors for various gene therapy applications due to their long-lasting transgene expression and wide spectrum of target cells. Recently, however, it has become apparent that there are considerable differences in the efficiencies of transduction of different cell types by AAVs. Here, we analyzed the efficiencies of transduction and the transport mechanisms of AAV type 2 (AAV-2) in different cell types, emphasizing endothelial cells. Expression analyses in both cultured cells and the rabbit carotid artery assay showed a remarkably low level of endothelial cell transduction in comparison to the highly permissive cell types. The study of the endosomal pathways of AAV-2 with fluorescently labeled virus showed clear targeting of the Golgi area in permissive cell lines, but this phenomenon was absent in the endothelial cell line EAhy-926. On the other hand, the response to the block of endosomal acidification by bafilomycin A1 also showed differences among the permissive cell types. We also analyzed the effect of proteasome inhibitors on endothelial cells, but their impact on the primary cells and in vivo was not significant. On the contrary, analysis of the expression pattern of heparan sulfate proteoglycans (HSPGs), the primary receptors of AAV-2, revealed massive deposits of HSPG in the extracellular matrix of endothelial cells. The matrix-associated receptors may therefore compete for virus binding and reduce transduction in endothelial cells. Accordingly, in endothelial cells detached from their matrix, AAV-2 transduction was significantly increased. Altogether, these results point to a more complex cell-type-specific mode of transduction of AAV-2 than previously appreciated. PMID:12388714

  12. Inflammation-induced endothelial cell-derived extracellular vesicles modulate the cellular status of pericytes.

    PubMed

    Yamamoto, Seiji; Niida, Shumpei; Azuma, Erika; Yanagibashi, Tsutomu; Muramatsu, Masashi; Huang, Ting Ting; Sagara, Hiroshi; Higaki, Sayuri; Ikutani, Masashi; Nagai, Yoshinori; Takatsu, Kiyoshi; Miyazaki, Kenji; Hamashima, Takeru; Mori, Hisashi; Matsuda, Naoyuki; Ishii, Yoko; Sasahara, Masakiyo

    2015-01-01

    Emerging lines of evidence have shown that extracellular vesicles (EVs) mediate cell-to-cell communication by exporting encapsulated materials, such as microRNAs (miRNAs), to target cells. Endothelial cell-derived EVs (E-EVs) are upregulated in circulating blood in different pathological conditions; however, the characteristics and the role of these E-EVs are not yet well understood. In vitro studies were conducted to determine the role of inflammation-induced E-EVs in the cell-to-cell communication between vascular endothelial cells and pericytes/vSMCs. Stimulation with inflammatory cytokines and endotoxin immediately induced release of shedding type E-EVs from the vascular endothelial cells, and flow cytometry showed that the induction was dose dependent. MiRNA array analyses revealed that group of miRNAs were specifically increased in the inflammation-induced E-EVs. E-EVs added to the culture media of cerebrovascular pericytes were incorporated into the cells. The E-EV-supplemented cells showed highly induced mRNA and protein expression of VEGF-B, which was assumed to be a downstream target of the miRNA that was increased within the E-EVs after inflammatory stimulation. The results suggest that E-EVs mediate inflammation-induced endothelial cell-pericyte/vSMC communication, and the miRNAs encapsulated within the E-EVs may play a role in regulating target cell function. E-EVs may be new therapeutic targets for the treatment of inflammatory diseases. PMID:25687367

  13. Corneal Endothelial Cell Density and Morphology in Healthy Turkish Eyes

    PubMed Central

    Arıcı, Ceyhun; Arslan, Osman Sevki; Dikkaya, Funda

    2014-01-01

    Purpose. To describe the normative values of corneal endothelial cell density, morphology, and central corneal thickness in healthy Turkish eyes. Methods. Specular microscopy was performed in 252 eyes of 126 healthy volunteers (M : F, 42 : 84). Parameters studied included mean endothelial cell density (MCD), mean cell area (MCA), coefficient of variation (CV) in cell size, percentage of hexagonal cells, and central corneal thickness (CCT). Results. The mean age of volunteers was 44.3 ± 13.5 (range, 20 to 70) years. There was a statistically significant decrease in MCD (P < 0.001; correlation, −0.388) and percentage of hexagonal cells, (P < 0.001; correlation, −0.199) with age. There was also a statistically significant increase in MCA (P < 0.001; correlation, 0.363) with increasing age. There was no statistically significant difference in MCD, MCA, CV in cell size, percentage of hexagonal cells, and CCT between genders and there was also no significant difference in these parameters between fellow eyes of subjects. Conclusions. Normotive data for the endothelium in the Turkish population are reported. Endothelial cell density in the Turkish eyes is less than that described in the Japanese, American, Chinese, and Filipino eyes and higher than that described in Indian, Thai, and Iranian eyes. PMID:24683494

  14. CARD14 Expression in Dermal Endothelial Cells in Psoriasis

    PubMed Central

    Harden, Jamie L.; Lewis, Steven M.; Pierson, Katherine C.; Suárez-Fariñas, Mayte; Lentini, Tim; Ortenzio, Francesca S.; Zaba, Lisa C.; Goldbach-Mansky, Raphaela; Bowcock, Anne M.; Lowes, Michelle A.

    2014-01-01

    Mutations in the caspase recruitment domain, family member 14 (CARD14) gene have recently been described in psoriasis patients, and explain the psoriasis susceptibility locus 2 (PSORS2). CARD14 is a scaffolding protein that regulates NF-κB activation, and psoriasis-associated CARD14 mutations lead to enhanced NF-κB signaling. CARD14 is expressed mainly in epidermal keratinocytes, but also in unidentified dermal cells. In this manuscript, the identity of the dermal cell types expressing CARD14, as well the potential functional consequence of overactive CARD14 in these dermal cell types, was determined. Using two-color immunofluorescence, dermal CARD14 did not co-localize with T-cells, dendritic cells, or macrophages. However, dermal CARD14 did highly co-localize with CD31+ endothelial cells (ECs). CARD14 was also expressed non-dermal endothelial cells, such as aortic endothelial cells, which may indicate a role of CARD14+ECs in the systemic inflammation and cardiovascular comorbidities associated with psoriasis. Additionally, phosphorylated NF-κB was found in psoriatic CARD14+ CD31+ ECs, demonstrating this pathway is active in dermal ECs in psoriasis. Transfection of dermal ECs with psoriasis-associated CARD14 mutations resulted in increased expression of several chemokines, including CXCL10, IL-8, and CCL2. These results provide preliminary evidence that CARD14 expression in ECs may contribute to psoriasis through increased expression of chemokines and facilitating recruitment of immune cells into skin. PMID:25369198

  15. CARD14 expression in dermal endothelial cells in psoriasis.

    PubMed

    Harden, Jamie L; Lewis, Steven M; Pierson, Katherine C; Suárez-Fariñas, Mayte; Lentini, Tim; Ortenzio, Francesca S; Zaba, Lisa C; Goldbach-Mansky, Raphaela; Bowcock, Anne M; Lowes, Michelle A

    2014-01-01

    Mutations in the caspase recruitment domain, family member 14 (CARD14) gene have recently been described in psoriasis patients, and explain the psoriasis susceptibility locus 2 (PSORS2). CARD14 is a scaffolding protein that regulates NF-κB activation, and psoriasis-associated CARD14 mutations lead to enhanced NF-κB signaling. CARD14 is expressed mainly in epidermal keratinocytes, but also in unidentified dermal cells. In this manuscript, the identity of the dermal cell types expressing CARD14, as well the potential functional consequence of overactive CARD14 in these dermal cell types, was determined. Using two-color immunofluorescence, dermal CARD14 did not co-localize with T-cells, dendritic cells, or macrophages. However, dermal CARD14 did highly co-localize with CD31(+) endothelial cells (ECs). CARD14 was also expressed non-dermal endothelial cells, such as aortic endothelial cells, which may indicate a role of CARD14(+)ECs in the systemic inflammation and cardiovascular comorbidities associated with psoriasis. Additionally, phosphorylated NF-κB was found in psoriatic CARD14(+) CD31(+) ECs, demonstrating this pathway is active in dermal ECs in psoriasis. Transfection of dermal ECs with psoriasis-associated CARD14 mutations resulted in increased expression of several chemokines, including CXCL10, IL-8, and CCL2. These results provide preliminary evidence that CARD14 expression in ECs may contribute to psoriasis through increased expression of chemokines and facilitating recruitment of immune cells into skin. PMID:25369198

  16. Capture of endothelial cells under flow using immobilized vascular endothelial growth factor.

    PubMed

    Smith, Randall J; Koobatian, Maxwell T; Shahini, Aref; Swartz, Daniel D; Andreadis, Stelios T

    2015-05-01

    We demonstrate the ability of immobilized vascular endothelial growth factor (VEGF) to capture endothelial cells (EC) with high specificity under fluid flow. To this end, we engineered a surface consisting of heparin bound to poly-l-lysine to permit immobilization of VEGF through the C-terminal heparin-binding domain. The immobilized growth factor retained its biological activity as shown by proliferation of EC and prolonged activation of KDR signaling. Using a microfluidic device we assessed the ability to capture EC under a range of shear stresses from low (0.5 dyne/cm(2)) to physiological (15 dyne/cm(2)). Capture was significant for all shear stresses tested. Immobilized VEGF was highly selective for EC as evidenced by significant capture of human umbilical vein and ovine pulmonary artery EC but no capture of human dermal fibroblasts, human hair follicle derived mesenchymal stem cells, or mouse fibroblasts. Further, VEGF could capture EC from mixtures with non-EC under low and high shear conditions as well as from complex fluids like whole human blood under high shear. Our findings may have far reaching implications, as they suggest that VEGF could be used to promote endothelialization of vascular grafts or neovascularization of implanted tissues by rare but continuously circulating EC. PMID:25771020

  17. Factors associated with graft survival and endothelial cell density after Descemet's stripping automated endothelial keratoplasty.

    PubMed

    Ishii, Nobuhito; Yamaguchi, Takefumi; Yazu, Hiroyuki; Satake, Yoshiyuki; Yoshida, Akitoshi; Shimazaki, Jun

    2016-01-01

    Postoperative endothelial cell loss leads to graft failure after corneal transplantation, and is one of the important issues for long-term prognosis. The objective of this study was to identify clinical factors affecting graft survival and postoperative endothelial cell density (ECD) after Descemet's stripping automated endothelial keratoplasty (DSAEK). A total of 198 consecutive Japanese patients (225 eyes) who underwent DSAEK were analysed using Cox proportional hazard regression and multiple linear regression models. The candidate factors included recipient age; gender; diagnosis; pre-existing iris damage state, scored based on its severity; the number of previous intraocular surgeries; graft ECD; graft diameter; simultaneous cataract surgery; surgeons experience; intraoperative iris damage; postoperative rebubbling; and graft rejection. Eyes with higher pre-existing iris damage score and more number of previous intraocular surgery had a significantly higher risk of graft failure (HR = 8.53; P < 0.0001, and HR = 2.66; P = 0.026, respectively). Higher pre-existing iris damage score, lower graft ECD, and smaller graft diameter were identified as significant predisposing factors for lower postoperative ECD. The results show that iris damage status before DSAEK may be clinically useful in predicting the postoperative course. Avoiding intraoperative iris damage, especially in eyes with low ECD can change the prognosis of future DSAEK. PMID:27121659

  18. METABOLIC CAPACITY REGULATES IRON HOMEOSTATIS IN ENDOTHELIAL CELLS

    EPA Science Inventory

    The sensitivity of endothelial cells to oxidative stress and the high concentrations of iron in mitochondria led us to test the hypotheses that (1) changes in respiratory capacity alter iron homeostasis, and (2) lack of aerobic metabolism decreases labile iron stores and attenuat...

  19. Endothelial cell expression of haemoglobin α regulates nitric oxide signalling.

    PubMed

    Straub, Adam C; Lohman, Alexander W; Billaud, Marie; Johnstone, Scott R; Dwyer, Scott T; Lee, Monica Y; Bortz, Pamela Schoppee; Best, Angela K; Columbus, Linda; Gaston, Benjamin; Isakson, Brant E

    2012-11-15

    Models of unregulated nitric oxide (NO) diffusion do not consistently account for the biochemistry of NO synthase (NOS)-dependent signalling in many cell systems. For example, endothelial NOS controls blood pressure, blood flow and oxygen delivery through its effect on vascular smooth muscle tone, but the regulation of these processes is not adequately explained by simple NO diffusion from endothelium to smooth muscle. Here we report a new model for the regulation of NO signalling by demonstrating that haemoglobin (Hb) α (encoded by the HBA1 and HBA2 genes in humans) is expressed in human and mouse arterial endothelial cells and enriched at the myoendothelial junction, where it regulates the effects of NO on vascular reactivity. Notably, this function is unique to Hb α and is abrogated by its genetic depletion. Mechanistically, endothelial Hb α haem iron in the Fe(3+) state permits NO signalling, and this signalling is shut off when Hb α is reduced to the Fe(2+) state by endothelial cytochrome b5 reductase 3 (CYB5R3, also known as diaphorase 1). Genetic and pharmacological inhibition of CYB5R3 increases NO bioactivity in small arteries. These data reveal a new mechanism by which the regulation of the intracellular Hb α oxidation state controls NOS signalling in non-erythroid cells. This model may be relevant to haem-containing globins in a broad range of NOS-containing somatic cells. PMID:23123858

  20. Virulent Treponema pallidum activates human vascular endothelial cells.

    PubMed

    Riley, B S; Oppenheimer-Marks, N; Hansen, E J; Radolf, J D; Norgard, M V

    1992-03-01

    Perivascular lymphocytic infiltration, fibrin deposition, and endothelial cell abnormalities consistent with cellular activation are prominent histopathologic features of syphilis, a sexually transmitted disease caused by the spirochetal bacterium Treponema pallidum. Because activated endothelial cells play important roles in lymphocyte homing and hemostasis, the ability of virulent T. pallidum to activate cultured human umbilical vein endothelial cells (HUVEC) was investigated. T. pallidum induced the expression of intercellular adhesion molecule-1 (ICAM-1) and procoagulant activity on the surface of HUVEC. Electron microscopy of T. pallidum-stimulated HUVEC revealed extensive networks of fibrin strands not observed in cultures without treponemes. ICAM-1 expression in HUVEC also was promoted by a 47-kDa integral membrane lipoprotein purified from T. pallidum, implicating a role for spirochete membrane lipoproteins in endothelial cell activation. The combined findings are consistent with the pathology of syphilis and provide the first evidence that a pathogenic spirochetal bacterium such as T. pallidum or its constituent integral membrane lipoprotein(s) can activate directly host vascular endothelium. PMID:1347056

  1. Are endothelial cell bioeffects from acoustic droplet vaporization proximity dependent?

    NASA Astrophysics Data System (ADS)

    Seda, Robinson; Li, David; Fowlkes, J. Brian; Bull, Joseph

    2013-11-01

    Acoustic droplet vaporization (ADV) produces gas microbubbles that provide a means of selective occlusion in gas embolotherapy. Vaporization and subsequent occlusion occur inside blood vessels supplying the targeted tissue, such as tumors. Theoretical and computational studies showed that ADV within a vessel can impart high fluid mechanical stresses on the vessel wall. Previous in vitro studies have demonstrated that vaporization at an endothelial layer may affect cell attachment and viability. The current study is aimed at investigating the role of vaporization distance away from the endothelial layer. HUVECs were cultured in OptiCell™ chambers until reaching confluence. Dodecafluoropentane microdroplets were added, attaining a 10:1 droplet to cell ratio. A single ultrasound pulse (7.5 MHz) consisting of 16 cycles (~ 2 μs) and a 5 MPa peak rarefactional pressure was used to produce ADV while varying the vaporization distance from the endothelial layer (0 μm, 500 μm, 1000 μm). Results indicated that cell attachment and viability was significantly different if the distance was 0 μm (at the endothelial layer). Other distances were not significantly different from the control. ADV will significantly affect the endothelium if droplets are in direct contact with the cells. Droplet concentration and flow conditions inside blood vessels may play an important role. This work was supported by NIH grant R01EB006476.

  2. Endothelial Cells Promote Pigmentation through Endothelin Receptor B Activation.

    PubMed

    Regazzetti, Claire; De Donatis, Gian Marco; Ghorbel, Houda Hammami; Cardot-Leccia, Nathalie; Ambrosetti, Damien; Bahadoran, Philippe; Chignon-Sicard, Bérengère; Lacour, Jean-Philippe; Ballotti, Robert; Mahns, Andre; Passeron, Thierry

    2015-12-01

    Findings of increased vascularization in melasma lesions and hyperpigmentation in acquired bilateral telangiectatic macules suggested a link between pigmentation and vascularization. Using high-magnification digital epiluminescence dermatoscopy, laser confocal microscopy, and histological examination, we showed that benign vascular lesions of the skin have restricted but significant hyperpigmentation compared with the surrounding skin. We then studied the role of microvascular endothelial cells in regulating skin pigmentation using an in vitro co-culture model using endothelial cells and melanocytes. These experiments showed that endothelin 1 released by microvascular endothelial cells induces increased melanogenesis signaling, characterized by microphthalmia-associated transcription factor phosphorylation, and increased tyrosinase and dopachrome tautomerase levels. Immunostaining for endothelin 1 in vascular lesions confirmed the increased expression on the basal layer of the epidermis above small vessels compared with perilesional skin. Endothelin acts through the activation of endothelin receptor B and the mitogen-activated protein kinase, extracellular signal-regulated kinase (ERK)1/2, and p38, to induce melanogenesis. Finally, culturing of reconstructed skin with microvascular endothelial cells led to increased skin pigmentation that could be prevented by inhibiting EDNRB. Taken together these results demonstrated the role of underlying microvascularization in skin pigmentation, a finding that could open new fields of research for regulating physiological pigmentation and for treating pigmentation disorders such as melasma. PMID:26308584

  3. Measles virus hemagglutinin mediates monocyte aggregation and increased adherence to measles-infected endothelial cells.

    PubMed

    Soilu-Hänninen, M; Hänninen, A; Ilonen, J; Salmi, A; Salonen, R

    1996-09-01

    The effect of measles virus (MV) infection on monocyte adhesion was studied using human peripheral blood monocytes and monocytic and endothelial cell lines. The infection of monocytic U-937 cells led to the formation of large cellular aggregates. Aggregation was independent of intercellular adhesion molecule-1 (ICAM-1)/lymphocyte function-associated antigen-1 (LFA-1), but could be inhibited by monoclonal antibodies (mAb) against the MV hemagglutinin glycoprotein (MV-H). mAb against the MV receptor, CD46, also blocked aggregation. No significant changes in the cell surface expression of adhesion molecules CD11a, CD11b, CD11c, CD18, CD54, CD44, CD49d (alpha 4-integrin) and CD62L (L-selectin) were observed on MV-infected monocytes. Infection of a human endothelial cell line, EAhy 926 (HEC), with MV led to a two-fold increase in 1CAM-1 expression and a two-fold increase in monocyte adherence to the HEC (from 22 +/- 1.6% to 42 +/- 4.8%). However, ICAM-1 mAb reduced monocyte adhesion to the control and MV-infected HEC to a similar degree, whereas anti-MV-H antibodies abolished the difference between binding to infected and control HEC. We conclude that MV hemagglutinin mediated both the homo typic aggregation in infected monocyte cultures and increased monocyte adherence to the infected endothelial cells. PMID:8884738

  4. Resistin increases monolayer permeability of human coronary artery endothelial cells.

    PubMed

    Jamaluddin, Md Saha; Yan, Shaoyu; Lü, Jianming; Liang, Zhengdong; Yao, Qizhi; Chen, Changyi

    2013-01-01

    Resistin has been linked to obesity, insulin resistance, atherosclerosis, and the development of cardiovascular disease. Nevertheless, the effects and the molecular mechanisms of resistin on endothelial permeability, a key event in the development of atherosclerosis, inflammation, and vascular disease, are largely unknown. In order to determine the effect of resistin on endothelial permeability, human coronary artery endothelial cells (HCAECs) were treated with clinically relevant concentrations of resistin and the endothelial permeability was measured using the Transwell system with a Texas-Red-labeled dextran tracer. The permeability of HCAEC monolayers treated with resistin (80 ng/mL) was 51% higher than the permeability of control monolayers (P<0.05). The mRNA levels of tight junction proteins zonula occludens-1 (ZO-1) and occludin in resistin-treated cells were 37% and 42% lower, respectively, than the corresponding levels in untreated cells. The protein levels of these molecules in resistin-treated cells were significantly reduced by 35% and 37%, respectively (P<0.05), as shown by flow cytometry and Western blot analysis. Superoxide dismutase (SOD) mimetic MnTBAP effectively blocked the resistin-mediated reduction of ZO-1 and occludin levels in HCAECs. In addition, superoxide anion production was increased from 21% (untreated cells) to 55% (cells treated with 40 ng/mL resistin), and 64% (resistin, 80 mg/mL) (P<0.05). The natural antioxidant Ginkgolide A effectively inhibited resistin-induced increase in permeability and the increase in superoxide anion production in HCAECs. Furthermore, resistin treatment significantly activated p38 MAPK, but not ERK1/2. Pretreatment of HCAECs with a p38 inhibitor effectively blocked resistin-induced permeability. These results provide new evidence that resistin may contribute to the vascular lesion formation via increasing endothelial permeability through the mechanism of oxidative stress and the activation of p38 MAPK. PMID

  5. Resistin Increases Monolayer Permeability of Human Coronary Artery Endothelial Cells

    PubMed Central

    Jamaluddin, Md Saha; Yan, Shaoyu; Lü, Jianming; Liang, Zhengdong; Yao, Qizhi; Chen, Changyi

    2013-01-01

    Resistin has been linked to obesity, insulin resistance, atherosclerosis, and the development of cardiovascular disease. Nevertheless, the effects and the molecular mechanisms of resistin on endothelial permeability, a key event in the development of atherosclerosis, inflammation, and vascular disease, are largely unknown. In order to determine the effect of resistin on endothelial permeability, human coronary artery endothelial cells (HCAECs) were treated with clinically relevant concentrations of resistin and the endothelial permeability was measured using the Transwell system with a Texas-Red-labeled dextran tracer. The permeability of HCAEC monolayers treated with resistin (80 ng/mL) was 51% higher than the permeability of control monolayers (P<0.05). The mRNA levels of tight junction proteins zonula occludens-1 (ZO-1) and occludin in resistin-treated cells were 37% and 42% lower, respectively, than the corresponding levels in untreated cells. The protein levels of these molecules in resistin-treated cells were significantly reduced by 35% and 37%, respectively (P<0.05), as shown by flow cytometry and Western blot analysis. Superoxide dismutase (SOD) mimetic MnTBAP effectively blocked the resistin-mediated reduction of ZO-1 and occludin levels in HCAECs. In addition, superoxide anion production was increased from 21% (untreated cells) to 55% (cells treated with 40 ng/mL resistin), and 64% (resistin, 80 mg/mL) (P<0.05). The natural antioxidant Ginkgolide A effectively inhibited resistin-induced increase in permeability and the increase in superoxide anion production in HCAECs. Furthermore, resistin treatment significantly activated p38 MAPK, but not ERK1/2. Pretreatment of HCAECs with a p38 inhibitor effectively blocked resistin-induced permeability. These results provide new evidence that resistin may contribute to the vascular lesion formation via increasing endothelial permeability through the mechanism of oxidative stress and the activation of p38 MAPK. PMID

  6. Dietary macronutrients and the aging liver sinusoidal endothelial cell.

    PubMed

    Cogger, Victoria Carroll; Mohamad, Mashani; Solon-Biet, Samantha Marie; Senior, Alistair M; Warren, Alessandra; O'Reilly, Jennifer Nicole; Tung, Bui Thanh; Svistounov, Dmitri; McMahon, Aisling Clare; Fraser, Robin; Raubenheimer, David; Holmes, Andrew J; Simpson, Stephen James; Le Couteur, David George

    2016-05-01

    Fenestrations are pores within the liver sinusoidal endothelial cells (LSECs) that line the sinusoids of the highly vascularized liver. Fenestrations facilitate the transfer of substrates between blood and hepatocytes. With pseudocapillarization of the hepatic sinusoid in old age, there is a loss of fenestrations. LSECs are uniquely exposed to gut-derived dietary and microbial substrates delivered by the portal circulation to the liver. Here we studied the effect of 25 diets varying in content of macronutrients and energy on LSEC fenestrations using the Geometric Framework method in a large cohort of mice aged 15 mo. Macronutrient distribution rather than total food or energy intake was associated with changes in fenestrations. Porosity and frequency were inversely associated with dietary fat intake, while fenestration diameter was inversely associated with protein or carbohydrate intake. Fenestrations were also linked to diet-induced changes in gut microbiome, with increased fenestrations associated with higher abundance of Firmicutes and reduced abundance of Bacteroidetes Diet-induced changes in levels of several fatty acids (C16:0, C19:0, and C20:4) were also significantly inversely associated with fenestrations, suggesting a link between dietary fat and modulation of lipid rafts in the LSECs. Diet influences fenestrations and these data reflect both the key role of the LSECs in clearing gut-derived molecules from the vascular circulation and the impact these molecules have on LSEC morphology. PMID:26921440

  7. Soluble CD40 ligand induces endothelial dysfunction in human and porcine coronary artery endothelial cells.

    PubMed

    Chen, Changyi; Chai, Hong; Wang, Xinwen; Jiang, Jun; Jamaluddin, Md Saha; Liao, Dan; Zhang, Yuqing; Wang, Hao; Bharadwaj, Uddalak; Zhang, Sheng; Li, Min; Lin, Peter; Yao, Qizhi

    2008-10-15

    The purpose of this study was to determine the effects and mechanisms of sCD40L on endothelial dysfunction in both human coronary artery endothelial cells (HCAECs) and porcine coronary artery rings. HCAECs treated with sCD40L showed significant reductions of endothelial nitric oxide synthase (eNOS) mRNA and protein levels, eNOS mRNA stability, eNOS enzyme activity, and cellular NO levels, whereas superoxide anion (O(2)(-)) production was significantly increased. sCD40L enhanced eNOS mRNA 3'UTR binding to cytoplasmic molecules and induced a unique expression pattern of 95 microRNAs. sCD40L significantly decreased mitochondrial membrane potential, and catalase and SOD activities, whereas it increased NADPH oxidase (NOX) activity. sCD40L increased phosphorylation of MAPKs p38 and ERK1/2 as well as IkappaBalpha and enhanced NF-kappaB nuclear translocation. In porcine coronary arteries, sCD40L significantly decreased endothelium-dependent vasorelaxation and eNOS mRNA levels, whereas it increased O(2)(-) levels. Antioxidant seleno-l-methionine; chemical inhibitors of p38, ERK1/2, and mitochondrial complex II; as well as dominant negative mutant forms of IkappaBalpha and NOX4 effectively blocked sCD40L-induced eNOS down-regulation in HCAECs. Thus, sCD40L reduces eNOS levels, whereas it increases oxidative stress through the unique molecular mechanisms involving eNOS mRNA stability, 3'UTR-binding molecules, microRNAs, mitochondrial function, ROS-related enzymes, p38, ERK1/2, and NF-kappaB signal pathways in endothelial cells. PMID:18658029

  8. TRPV1 mediates cellular uptake of anandamide and thus promotes endothelial cell proliferation and network-formation

    PubMed Central

    Hofmann, Nicole A.; Barth, Sonja; Waldeck-Weiermair, Markus; Klec, Christiane; Strunk, Dirk; Malli, Roland; Graier, Wolfgang F.

    2014-01-01

    ABSTRACT Anandamide (N-arachidonyl ethanolamide, AEA) is an endogenous cannabinoid that is involved in various pathological conditions, including cardiovascular diseases and tumor-angiogenesis. Herein, we tested the involvement of classical cannabinoid receptors (CBRs) and the Ca2+-channel transient receptor potential vanilloid 1 (TRPV1) on cellular AEA uptake and its effect on endothelial cell proliferation and network-formation. Uptake of the fluorescence-labeled anandamide (SKM4-45-1) was monitored in human endothelial colony-forming cells (ECFCs) and a human endothelial-vein cell line (EA.hy926). Involvement of the receptors during AEA translocation was determined by selective pharmacological inhibition (AM251, SR144528, CID16020046, SB366791) and molecular interference by TRPV1-selective siRNA-mediated knock-down and TRPV1 overexpression. We show that exclusively TRPV1 contributes essentially to AEA transport into endothelial cells in a Ca2+-independent manner. This TRPV1 function is a prerequisite for AEA-induced endothelial cell proliferation and network-formation. Our findings point to a so far unknown moonlighting function of TRPV1 as Ca2+-independent contributor/regulator of AEA uptake. We propose TRPV1 as representing a promising target for development of pharmacological therapies against AEA-triggered endothelial cell functions, including their stimulatory effect on tumor-angiogenesis. PMID:25395667

  9. Apoptosis and calcification of vascular endothelial cell under hyperhomocysteinemia.

    PubMed

    Fang, Kuaifa; Chen, Zhujun; Liu, Meng; Peng, Jian; Wu, Pingsheng

    2015-01-01

    In recent years, it is found that increase in Hcy level in blood can directly or indirectly cause vascular endothelial cell injury and induce vascular calcification. However, the mechanism of vascular endothelial cell injury and vascular calcification has not been studied thoroughly. This paper carried out experiment for research aiming at discussing the effect and action mechanism of Hhcy on endothelial cells and vascular calcification. Firstly, human umbilical vein endothelial cells (HUVECs) were cultured and then intervened by Hcy of different concentrations (0, 0.01, 0.1, 1.0, 3.0, 5.0 mmol/L) and at different action time (3, 6, 12, 24 h). Then apoptosis rate and reactive oxygen were detected by flow cytometry. At the same time, the model for the culture of rat vascular calcification was set up and induced into Hhcy so as to detect the total plasma Hcy level and judge vascular calcification degree. The results showed that with the increase in Hcy concentration and extension of action period, the apoptosis rate and generation of reactive oxygen of HUVECs all significantly increased, and the differences were all statistically significant (P < 0.01). In animal calcification model, mass of black particle deposition was seen after Von Kossa staining of rat vessels in calcification group. Compared with the control group, the vascular calcium content, alkaline phosphatase activity and osteocalcin content in calcification group all increased (P < 0.01). The content of plasma lipid conjugated olefine from highest to lowest wasas follows: calcification plus homoetheionin, homoetheionin, and calcification group. There was no significant difference between the calcification group and control group. All these findings suggested that Hcy could induce the apoptosis of endothelial cells and its effect degree depended on its concentration and action period; Hhcy could promote the calcification of blood vessels, and its mechanism might relate with the strengthening of

  10. Methanolic Extract Isolated from Root of Lycoris aurea Inhibits Cancer Cell Growth and Endothelial Cell Tube Formation In Vitro

    PubMed Central

    Kang, Moo Rim; Lee, Chang Woo; Yun, Jieun; Oh, Soo Jin; Park, Song-Kyu; Lee, Kiho; Kim, Hwan Mook; Han, Sang-Bae; Kim, Hyoung-Chin

    2012-01-01

    In this study, we investigated the effect of methanolic extract isolated from the root of Lycoris aurea (LA) on the growth of cancer cells and the tube formation activity of endothelial cells. Various cancer cells were treated with LA at doses of 0.3, 1, 3, 10 or 30 μg/ml and LA significantly suppressed the growth of several cancer cell lines, including ACHN, HCT-15, K-562, MCF-7, PC-3 and SK-OV-3, in a dose-dependent manner. We also found that LA induced cell cycle arrest at G2/M phase in ACHN renal cell adenocarcinoma cells. Further study demonstrated that LA concentration-dependently inhibited the tube formation, which is a widely used in vitro model of reorganization stage of angiogenesis, in human umbilical vein endothelial cells. Collectively, these results show that LA inhibits the growth of cancer cells and tube formation of endothelial cells and the growth-inhibitory effect of LA might be mediated, at least in part, by blocking cell cycle progression. PMID:24278587

  11. Gossypol effects on endothelial cells and tumor blood flow

    SciTech Connect

    Benz, C.C.; Iyer, S.B.; Asgari, H.S.; Matlin, S.A.; Aronson, F.R. ); Barchowsky, A. )

    1991-01-01

    Isomers (-,+) of the antitumor agent gossypol (G) were studied for their ability to reduce tumor ATP and blood flow in rats bearing subcutaneously implanted pancreatic tumors. A 50% reduction in tumor ATP/Pi within 1h of a single injection of -G was associated with a 60% decline in tumor blood flow. To determine if these changes in tumor physiology could be due to a direct drug effect on tumor endothelium, G isomers were compared for their ability to alter protein ({sup 125}1-BSA) permeability and metabolic ({sup 32}P) labelling of cultured endothelial cells. Treatments for 1h produced no endothelial cell leakage, but 24h exposures to either -G or +G produced complete permeability of the monolayers to {sup 125}1-BSA. In contrast, 0.5-1.0h exposures to -G or +G produced 2 to 3-fold increases in phosphorylated 27kDa heat-shock protein, hsp-27. Hsp-27 phosphoprotein isoforms were differentially labelled following -G and +G exposures with the phosphorylation profile of -G appearing most similar to that of oxyradical producing agents known to induce hsp-27 and injure endothelial cells. The authors postulate that the tumor ischemic effects of -G are mediated by endothelial response to oxyradical production in a mechanism similar to that of tissue ischemia-reperfusion injury.

  12. Effect of Excessive Potassium Iodide on Rat Aorta Endothelial Cells.

    PubMed

    Zhang, Man; Zou, Xiaoyan; Lin, Xinying; Bian, Jianchao; Meng, Huicui; Liu, Dan

    2015-08-01

    The aim of the current study was to investigate the effect of excess iodine on rat aorta endothelial cells and the potential underlying mechanisms. Rat aorta endothelial cells were cultured with iodide ion (3506, 4076, 4647, 5218, 5789, 6360, 6931, and 7512 mg/L) for 48 h. Morphological changes of cells were observed with microscope after Wright-Giemsa staining and acridine orange staining. Cell proliferation was determined with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and cell apoptosis was assessed with flow cytometry. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), endothelial nitric oxide synthase (eNOS), induced nitric oxide synthase (iNOS), and concentrations of malondialdehyde (MDA), glutathione (GSH), and protein carbonyl in culture medium were determined with colorimetric method. The expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was detected by enzyme linked immunosorbent assay. The results showed that excess iodine induced abnormal morphologic changes of cells, inhibited cell proliferation, and increased apoptosis rate. Iodine also reduced the activity of SOD, GSH-Px, and concentrations of GSH and increased the concentrations of MDA and protein carbonyl in a dose-dependent manner. Moreover, excess iodine decreased the activity of eNOS and increased the activity of iNOS and the expression of ICAM-1 and VCAM-1 in culture medium. Our results suggested that excess iodine exposure increased oxidative stress, caused damage of vascular endothelial cells, and altered the expression of adhesion factors and the activity of NOS. These changes may explain the mechanisms underlying excess iodine-induced vascular injury. PMID:25690517

  13. Arteries are formed by vein-derived endothelial tip cells

    PubMed Central

    Xu, Cong; Hasan, Sana S.; Schmidt, Inga; Rocha, Susana F.; Pitulescu, Mara E.; Bussmann, Jeroen; Meyen, Dana; Raz, Erez; Adams, Ralf H.; Siekmann, Arndt F.

    2014-01-01

    Tissue vascularization entails the formation of a blood vessel plexus, which remodels into arteries and veins. Here we show, by using time-lapse imaging of zebrafish fin regeneration and genetic lineage tracing of endothelial cells in the mouse retina, that vein-derived endothelial tip cells contribute to emerging arteries. Our movies uncover that arterial-fated tip cells change migration direction and migrate backwards within the expanding vascular plexus. This behaviour critically depends on chemokine receptor cxcr4a function. We show that the relevant Cxcr4a ligand Cxcl12a selectively accumulates in newly forming bone tissue even when ubiquitously overexpressed, pointing towards a tissue-intrinsic mode of chemokine gradient formation. Furthermore, we find that cxcr4a mutant cells can contribute to developing arteries when in association with wild-type cells, suggesting collective migration of endothelial cells. Together, our findings reveal specific cell migratory behaviours in the developing blood vessel plexus and uncover a conserved mode of artery formation. PMID:25502622

  14. Senescence affects endothelial cells susceptibility to dengue virus infection.

    PubMed

    AbuBakar, Sazaly; Shu, Meng-Hooi; Johari, Jefree; Wong, Pooi-Fong

    2014-01-01

    Alteration in the endothelium leading to increased vascular permeability contributes to plasma leakage seen in dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). An earlier study showed that senescent endothelial cells (ECs) altered the ECs permeability. Here we investigated the susceptibility of senescing human umbilical vein endothelial cells (HUVECs) to dengue virus infection and determined if dengue virus infection induces HUVECs senescence. Our results suggest that DENV type-2 (DENV-2) foci forming unit (FFU) and extracellular virus RNA copy number were reduced by at least 35% and 85% in infection of the intermediate young and early senescent HUVECs, respectively, in comparison to infection of young HUVECs. No to low infectivity was recovered from infection of late senescent HUVECs. DENV infection also increases the percentage of HUVECs expressing senescence-associated (SA)-β-gal, cells arrested at the G2/M phase or 4N DNA content stage and cells with enlarged morphology, indicative of senescing cells. Alteration of HUVECs morphology was recorded using impedance-based real-time cell analysis system following DENV-2 infection. These results suggest that senescing HUVECs do not support DENV infection and DENV infection induces HUVECs senescence. The finding highlights the possible role of induction of senescence in DENV infection of the endothelial cells. PMID:24782642

  15. Characterization of the response of human bone marrow endothelial cells to in vitro irradiation.

    PubMed

    Gaugler, M H; Squiban, C; Claraz, M; Schweitzer, K; Weksler, B; Gourmelon, P; Van der Meeren, A

    1998-12-01

    Endothelial cell dysfunction is a classic consequence of radiation damage. Bone marrow endothelial cells (BMEC) are a critical component of the stroma in the regulation of haemopoiesis. In animal models, radiation-induced injury of BMEC has been described and a role for BMEC in haemopoietic regeneration after irradiation has been suggested. However, functions of BMEC involved in the haemopoietic regeneration have not been assessed. Therefore we studied the functional response of human BMEC to irradiation using the transformed human BMEC line (TrHBMEC) irradiated with 2. 5 or 10Gy. Our results showed a time- and a dose-dependent increase in damage to irradiated TrHBMEC measured by a decreased number of adherent cells which correlated with increased apoptosis and augmented release of soluble ICAM-1 and von Willebrand factor. 2 Gy irradiated TrHBMEC expressed more ICAM-1 on their surface than non-irradiated cells, whereas no change in VCAM-1, E-selectin and PECAM-1 expression was observed. An increased production of G-CSF, GM-CSF, IL-8, IL-6, IL-1alpha, IL-11, MIP-1alpha and SCF and no production of LIF, TNF-alpha, TPO and IL-3 by 2 Gy irradiated TrHBMEC was observed. The haemopoietic supportive function of TrHBMEC was not altered after a 2 Gy exposure. These results suggest that although radiation induces endothelial cell damage, irradiated cells still support the proliferation and the differentiation of CD34+ haemopoietic cells. PMID:9886309

  16. Effect of photobiomodulation on endothelial cell exposed to Bothrops jararaca venom.

    PubMed

    Franco, Ana Tereza Barufi; Silva, Luciana Miato Gonçalves; Costa, Marcília Silva; Zamuner, Silvia Fernanda; Vieira, Rodolfo Paula; de Fatima Pereira Teixeira, Catarina; Zamuner, Stella Regina

    2016-07-01

    Bleeding is a common feature in envenoming caused by Bothrops snake venom due to extensive damage to capillaries and venules, producing alterations in capillary endothelial cell morphology. It has been demonstrated, in vivo, that photobiomodulation (PBM) decreases hemorrhage after venom inoculation; however, the mechanism is unknown. Thus, the objective was to investigate the effects of PBM on a murine endothelial cell line (tEnd) exposed to Bothrops jararaca venom (BjV). Cells were exposed to BjV and irradiated once with either 660- or 780-nm wavelength laser light at energy densities of 4 and 5 J/cm(2), respectively, and irradiation time of 10 s. Cell integrity was analyzed by crystal violet and cell viability/mitochondrial metabolism by MTT assay. The release of lactic dehydrogenase (LDH) was quantified as a measure of cell damage. In addition, cytokine IL1-β levels were measured in the supernatant. PBM at 660 and 780 nm wavelength was able to increase cellular viability and decrease the release of LDH and the loss of cellular integrity. In addition, the concentration of pro-inflammatory cytokine IL1-β was reduced after PBM by both wavelengths. The data reported herein indicates that irradiation with red or near-infrared laser resulted in protection on endothelial cells after exposure to Bothrops venom and could be, at least in part, a reasonable explanation by the beneficial effects of PBM inhibiting the local effects induced by Bothrops venoms, in vivo. PMID:27147074

  17. Generation of functional endothelial-like cells from adult mouse germline-derived pluripotent stem cells.

    PubMed

    Kim, Julee; Eligehausen, Sarah; Stehling, Martin; Nikol, Sigrid; Ko, Kinarm; Waltenberger, Johannes; Klocke, Rainer

    2014-01-10

    Functional endothelial cells and their progenitors are required for vascular development, adequate vascular function, vascular repair and for cell-based therapies of ischemic diseases. Currently, cell therapy is limited by the low abundance of patient-derived cells and by the functional impairment of autologous endothelial progenitor cells (EPCs). In the present study, murine germline-derived pluripotent stem (gPS) cells were evaluated as a potential source for functional endothelial-like cells. Cells displaying an endothelial cell-like morphology were obtained from gPS cell-derived embryoid bodies using a combination of fluorescence-activated cell sorting (FACS)-based selection of CD31-positive cells and their subsequent cultivation on OP9 stromal cells in the presence of VEGF-A. Real-time reverse transcriptase polymerase chain reaction, FACS analysis and immunofluorescence staining showed that the gPS cell-derived endothelial-like cells (gPS-ECs) expressed endothelial cell-specific markers including von Willebrand Factor, Tie2, VEGFR2/Flk1, intercellular adhesion molecule 2 and vascular endothelial-cadherin. The high expression of ephrin B2, as compared to Eph B4 and VEGFR3, suggests an arterial rather than a venous or lymphatic differentiation. Their capability to take up Dil-conjugated acetylated low-density lipoprotein and to form capillary-like networks on matrigel confirmed their functionality. We conclude that gPS cells could be a novel source of endothelial cells potentially suitable for regenerative cell-based therapies for ischemic diseases. PMID:24333870

  18. Effect of Flow on Gene Regulation in Smooth Muscle Cells and Macromolecular Transport Across Endothelial Cell Monolayers

    NASA Technical Reports Server (NTRS)

    McIntire, Larry V.; Wagner, John E.; Papadaki, Maria; Whitson, Peggy A.; Eskin, Suzanne G.

    1996-01-01

    Endothelial cells line all of the vessels of the circulatory system, providing a non-thrombogenic conduit for blood flow; they regulate many complex functions in the vasculature, such as coagulation, fibrinolysis, platelet aggregation, vessel tone and growth, and leukocyte traffic; and they form the principal barrier to transport of substances between the blood and the surrounding tissue space. The permeability of endothelial cell changes with environmental stimuli; shear stress, in particular, applied either in vivo, or in vitro, induces changes in protein expression and secretion of vasoactive factors by endothelial cells. The ability to study the effects of shear on the macromolecular permeability of the cerebral vasculature is particularly important, since in no other place is the barrier function of the endothelium more important than in the brain. The endothelial cells of this organ have developed special barrier properties that keep the cerebral system from experiencing any drastic change in composition; together with glial cells, they form the blood brain barrier (BBB). We have studied the effect of flow on bovine BBB using flow chambers and tissue culture systems.

  19. Tight junction protein expression and barrier properties of immortalized mouse brain microvessel endothelial cells.

    PubMed

    Brown, Rachel C; Morris, Andrew P; O'Neil, Roger G

    2007-01-26

    Understanding the molecular and biochemical mechanisms regulating the blood-brain barrier is aided by in vitro model systems. Many studies have used primary cultures of brain microvessel endothelial cells for this purpose. However, primary cultures limit the generation of material for molecular and biochemical assays since cells grow slowly, are prone to contamination by other neurovascular unit cells, and lose blood-brain barrier characteristics when passaged. To address these issues, immortalized cell lines have been generated. In these studies, we assessed the suitability of the immortalized mouse brain endothelial cell line, bEnd3, as a blood-brain barrier model. RT-PCR and immunofluorescence indicated expression of multiple tight junction proteins. bEnd3 cells formed barriers to radiolabeled sucrose, and responded like primary cultures to disrupting stimuli. Exposing cells to serum-free media on their basolateral side significantly decreased paracellular permeability; astrocyte-conditioned media did not enhance barrier properties. The serum-free media-induced decrease in permeability was correlated with an increase in claudin-5 and zonula occludens-1 immunofluorescence at cell-cell contracts. We conclude that bEnd3 cells are an attractive candidate as a model of the blood-brain barrier due to their rapid growth, maintenance of blood-brain barrier characteristics over repeated passages, formation of functional barriers and amenability to numerous molecular interventions. PMID:17169347

  20. Effects of nano-scaled particles on endothelial cell function in vitro: studies on viability, proliferation and inflammation.

    PubMed

    Peters, Kirsten; Unger, Ronald E; Kirkpatrick, C James; Gatti, Antonietta M; Monari, Emanuela

    2004-04-01

    Recent studies give support for a connection between the presence of inorganic particles (of microm and nm size) in different organs and tissues and the development of inflammatory foci, called granulomas. As the potential source of particles (e.g. porcelain dental bridges) and the location of particle detection were topographically far apart, a distribution via the blood stream appears highly probable. Thus, endothelial cells, which line the inner surface of blood vessels, would come into direct contact with these particles, making particle-endothelial interactions potentially pathogenically relevant. The objective of this study was to evaluate the effects that five different nano-scaled particles (PVC, TiO2, SiO2, Co, Ni) have on endothelial cell function and viability. Therefore, human endothelial cells were exposed to different amounts of the above-mentioned particles. Although most particle types are shown to be internalised (except Ni-particles), only Co-particles possessed cytotoxic effects. Furthermore, an impairment of the proliferative activity and a pro-inflammatory stimulation of endothelial cells were induced by exposure to Co- and, to a lesser extent, by SiO2-particles. If a pro-inflammatory stimulation of endothelial cells occurs in vivo, a chronic inflammation could be a possible consequence. PMID:15332593

  1. Nylon-3 Polymers that Enable Selective Culture of Endothelial Cells

    PubMed Central

    Liu, Runhui; Chen, Xinyu; Gellman, Samuel H.; Masters, Kristyn S.

    2014-01-01

    Substrates that selectively encourage the growth of specific cell types are valuable for the engineering of complex tissues. Some cell-selective peptides have been identified from extracellular matrix proteins; these peptides have proven useful for biomaterials-based approaches to tissue repair or regeneration. However, there are very few examples of synthetic materials that display selectivity in supporting cell growth. We describe nylon-3 polymers that support in vitro culture of endothelial cells, but do not support the culture of smooth muscle cells or fibroblasts. These materials may be promising for vascular biomaterials applications. PMID:24156536

  2. Radioligand binding to muscarinic receptors of bovine aortic endothelial cells.

    PubMed

    Brunner, F; Kukovetz, W R

    1991-02-01

    1. Muscarinic receptors on endothelial cells of bovine thoracic aorta were characterized by binding assays in which (-)-[3H]-N-methyl quinuclidinyl benzilate ([3H]-NMeQNB) was used as radioligand. 2. Binding of [3H]-NMeQNB to crude membranes of freshly isolated endothelial cells was atropine-displaceable and of high affinity (KD = 0.48 nM) to a single class of sites (maximum binding capacity: 14 +/- 3 fmol mg-1 protein). Stereospecificity of the binding sites was demonstrated in experiments in which [3H]-NMeQNB binding was inhibited by dexetimide in the nanomolar range (KI = 0.63 nM) and by levetimide, its stereoisomer in the micromolar range (KI = 3.2 microM) (selectivity factor: approximately 5000). 3. Drug competition curves indicated a single class of binding sites for antagonists and the following apparent affinities (KI, nM): methyl atropine: 1.1: 4-diphenylacetoxy N-methyl piperidine methyl bromide (4-DAMP): 3.4; pirenzepine: 16; 11-[2-diethylamino-methyl)-1-piperidinyl- acetyl]-5,11-dihydro-6H-pyrido(2,3-b)1,4-benzodiazepine-6-one (AF-DX 116); 2.500. Competition of acetylcholine with [3H]-NMeQNB was best described by two affinity sites (or states) (KH = 0.82 microM, KL = 1.6 microM). In the presence of guanylimido diphosphate [Gpp(NH)p] (100 microM), acetylcholine affinity (IC50) was slightly, but significantly reduced (factor approximately 4). 4. Binding of [3H]-NMeQNB to freshly harvested intact cells was also atropine-displaceable, stereospecific (selectivity factor: approximately 3500) and of high affinity (KD = 0.35 nM). The maximum binding capacity (9 +/- 2 fmol mg-1 total cell protein) was comparable to that of membranes and corresponded to approximately 900 binding sites per endothelial cell. Binding to enzymatically harvested and cultured endothelial cells, or membranes derived therefrom, showed no atropine-displaceable binding. 5. The results suggest that (1) bovine aortic endothelial cells contain muscarinic binding sites with all necessary

  3. Characterization of atrial natriuretic peptide degradation by cell-surface peptidase activity on endothelial cells

    NASA Technical Reports Server (NTRS)

    Frost, S. J.; Whitson, P. A.

    1993-01-01

    Atrial natriuretic peptide (ANP) is a fluid-regulating peptide hormone that promotes vasorelaxation, natriuresis, and diuresis. The mechanisms for the release of ANP and for its clearance from the circulation play important roles in modulating its biological effects. Recently, we have reported that the cell surface of an endothelial cell line, CPA47, could degrade 125I-ANP in the presence of EDTA. In this study, we have characterized this degradation of 125I-ANP. The kinetics of ANP degradation by the surface of CPA47 cells were first order, with a Km of 320 +/- 60 nM and Vmax of 35 +/- 14 pmol of ANP degraded/10 min/10(5) cells at pH 7.4. ANP is degraded by the surface of CPA47 cells over a broad pH range from 7.0-8.5. Potato carboxypeptidase inhibitor and bestatin inhibited 125I-ANP degradation, suggesting that this degradative activity on the surface of CPA47 cells has exopeptidase characteristics. The selectivity of CPA47 cell-surface degradation of ANP was demonstrated when 125I-ANP degradation was inhibited in the presence of neuropeptide Y and angiotensin I and II but not bradykinin, bombesin, endothelin-1, or substance P. The C-terminal amino acids phe26 and tyr28 were deduced to be important for ANP interaction with the cell-surface peptidase(s) based on comparison of the IC50 of various ANP analogues and other natriuretic peptides for the inhibition of ANP degradation. These data suggest that a newly characterized divalent cation-independent exopeptidase(s) that selectively recognizes ANP and some other vasoactive peptides exists on the surface of endothelial cells.

  4. Improved Endothelial Function of Endothelial Cell Monolayer on the Soft Polyelectrolyte Multilayer Film with Matrix-Bound Vascular Endothelial Growth Factor.

    PubMed

    Chang, Hao; Hu, Mi; Zhang, He; Ren, Ke-Feng; Li, Bo-Chao; Li, Huan; Wang, Li-Mei; Lei, Wen-Xi; Ji, Jian

    2016-06-15

    Endothelialization on the vascular implants is of great importance for prevention of undesired postimplantation symptoms. However, endothelial dysfunction of regenerated endothelial cell (EC) monolayer has been frequently observed, leading to severe complications, such as neointimal hyperplasia, late thrombosis, and neoatherosclerosis. It has significantly impeded long-term success of the therapy. So far, very little attention has been paid on endothelial function of EC monolayer. Bioinspired by the microenvironment of the endothelium in a blood vessel, this study described a soft polyelectrolyte multilayer film (PEM) through layer-by-layer assembly of poly(l-lysine) (PLL) and hyaluronan (HA). The (PLL/HA) PEM was chemically cross-linked and further incorporated with vascular endothelial growth factor. It demonstrated that this approach could promote EC adhesion and proliferation, further inducing formation of EC monolayer. Further, improved endothelial function of the EC monolayer was achieved as shown with the tighter integrity, higher production of nitric oxide, and expression level of endothelial function related genes, compared to EC monolayers on traditional substrates with high stiffness (e.g., glass, tissue culture polystyrene, and stainless steel). Our findings highlighted the influence of substrate stiffness on endothelial function of EC monolayer, giving a new strategy in the surface design of vascular implants. PMID:27223460

  5. The Dynamics and Mechanics of Endothelial Cell Spreading

    PubMed Central

    Reinhart-King, Cynthia A.; Dembo, Micah; Hammer, Daniel A.

    2005-01-01

    Cell adhesion to extracellular matrix is mediated by receptor-ligand interactions. When a cell first contacts a surface, it spreads, exerting traction forces against the surface and forming new bonds as its contact area expands. Here, we examined the changes in shape, actin polymerization, focal adhesion formation, and traction stress generation that accompany spreading of endothelial cells over a period of several hours. Bovine aortic endothelial cells were plated on polyacrylamide gels derivatized with a peptide containing the integrin binding sequence RGD, and changes in shape and traction force generation were measured. Notably, both the rate and extent of spreading increase with the density of substrate ligand. There are two prominent modes of spreading: at higher surface ligand densities cells tend to spread isotropically, whereas at lower densities of ligand the cells tend to spread anisotropically, by extending pseudopodia randomly distributed along the cell membrane. The extension of pseudopodia is followed by periods of growth in the cell body to interconnect these extensions. These cycles occur at very regular intervals and, furthermore, the extent of pseudopodial extension can be diminished by increasing the ligand density. Measurement of the traction forces exerted by the cell reveals that a cell is capable of exerting significant forces before either notable focal adhesion or stress fiber formation. Moreover, the total magnitude of force exerted by the cell is linearly related to the area of the cell during spreading. This study is the first to monitor the dynamic changes in the cell shape, spreading rate, and forces exerted during the early stages (first several hours) of endothelial cell adhesion. PMID:15849250

  6. Image analysis of human corneal endothelial cells based on fractal theory

    NASA Astrophysics Data System (ADS)

    Zhang, Zhi; Luo, Qingming; Zeng, Shaoqun; Zhang, Xinyu; Huang, Dexiu; Chen, Weiguo

    1999-09-01

    A fast method is developed to quantitatively characterize the shape of human corneal endothelial cells with fractal theory and applied to analyze microscopic photographs of human corneal endothelial cells. The results show that human corneal endothelial cells possess the third characterization parameter-- fractal dimension, besides another two characterization parameter (its size and shape). Compared with tradition method, this method has many advantages, such as automatism, speediness, parallel processing and can be used to analyze large numbers of endothelial cells, the obtained values are statistically significant, it offers a new approach for clinic diagnosis of endothelial cells.

  7. Endomucin prevents leukocyte–endothelial cell adhesion and has a critical role under resting and inflammatory conditions

    PubMed Central

    Zahr, Alisar; Alcaide, Pilar; Yang, Jinling; Jones, Alexander; Gregory, Meredith; dela Paz, Nathaniel G.; Patel-Hett, Sunita; Nevers, Tania; Koirala, Adarsha; Luscinskas, Francis W.; Saint-Geniez, Magali; Ksander, Bruce; D'Amore, Patricia A.; Argüeso, Pablo

    2016-01-01

    Endomucin is a membrane-bound glycoprotein expressed luminally by endothelial cells that line postcapillary venules, a primary site of leukocyte recruitment during inflammation. Here we show that endomucin abrogation on quiescent endothelial cells enables neutrophils to adhere firmly, via LFA-1-mediated binding to ICAM-1 constitutively expressed by endothelial cells. Moreover, TNF-α stimulation downregulates cell surface expression of endomucin concurrent with increased expression of adhesion molecules. Adenovirus-mediated expression of endomucin under inflammatory conditions prevents neutrophil adhesion in vitro and reduces the infiltration of CD45+ and NIMP-R14+ cells in vivo. These results indicate that endomucin prevents leukocyte contact with adhesion molecules in non-inflamed tissues and that downregulation of endomucin is critical to facilitate adhesion of leukocytes into inflamed tissues. PMID:26831939

  8. Endomucin prevents leukocyte-endothelial cell adhesion and has a critical role under resting and inflammatory conditions.

    PubMed

    Zahr, Alisar; Alcaide, Pilar; Yang, Jinling; Jones, Alexander; Gregory, Meredith; dela Paz, Nathaniel G; Patel-Hett, Sunita; Nevers, Tania; Koirala, Adarsha; Luscinskas, Francis W; Saint-Geniez, Magali; Ksander, Bruce; D'Amore, Patricia A; Argüeso, Pablo

    2016-01-01

    Endomucin is a membrane-bound glycoprotein expressed luminally by endothelial cells that line postcapillary venules, a primary site of leukocyte recruitment during inflammation. Here we show that endomucin abrogation on quiescent endothelial cells enables neutrophils to adhere firmly, via LFA-1-mediated binding to ICAM-1 constitutively expressed by endothelial cells. Moreover, TNF-α stimulation downregulates cell surface expression of endomucin concurrent with increased expression of adhesion molecules. Adenovirus-mediated expression of endomucin under inflammatory conditions prevents neutrophil adhesion in vitro and reduces the infiltration of CD45(+) and NIMP-R14(+) cells in vivo. These results indicate that endomucin prevents leukocyte contact with adhesion molecules in non-inflamed tissues and that downregulation of endomucin is critical to facilitate adhesion of leukocytes into inflamed tissues. PMID:26831939

  9. PKC/MAPK signaling suppression by retinal pericyte conditioned medium prevents retinal endothelial cell proliferation.

    PubMed

    Kondo, Tetsu; Hosoya, Ken-Ichi; Hori, Satoko; Tomi, Masatoshi; Ohtsuki, Sumio; Terasaki, Tetsuya

    2005-05-01

    Little is known about the regulation mechanism of endothelial cell proliferation by retinal pericytes. The purpose of this study was to elucidate the suppression mechanism of retinal capillary endothelial cell growth by soluble factors derived from retinal pericytes. Conditioned medium of retinal pericytes (rPCT1-CM) suppressed ischemia-induced retinal neovascularization. The growth and DNA synthesis of TR-iBRB2 cells, a conditionally immortalized rat retinal capillary endothelial cell line, were suppressed in a concentration-dependent manner by concentrated rPCT1-CM. The number of human cultured endothelial cells was also reduced by rPCT1-CM. These results provide the first evidence that CM from the cultivation of pericytes alone can inhibit retinal neovascularization in vivo and in vitro. Although the growth reduction of TR-iBRB2 cells was only partly reversed by treatment of rPCT1-CM with antibodies to transforming growth factor-beta1, it was completely lost by heat-treatment of rPCT1-CM, suggesting that anti-angiogenic factors are soluble proteins. The levels of expression of G1/S-phase-related proteins, such as cyclin D1, cyclin-dependent kinase (cdk)4, cdk6, and proliferating cell nuclear antigen, were reduced and a cdk inhibitor, p21(Cip1), was induced in rPCT1-CM-treated TR-iBRB2 cells. Moreover, phosphorylated p44/42 mitogen-activated protein kinase (p44/42 MAPK) in TR-iBRB2 cells was reduced by rPCT1-CM treatment and phosphorylated protein kinase C (PKC)alpha/betaII, which is upstream of p44/42 MAPK, was also suppressed. In conclusion, CM from retinal pericytes suppresses PKC-p44/42 MAPK signaling, inhibits endothelial cell growth, and prevents retinal neovascularization. Anti-angiogenic factors derived from retinal pericytes are likely to play a critical role in the regulation of retinal endothelial cell growth. PMID:15499572

  10. XIAP reverses various functional activities of FRNK in endothelial cells

    SciTech Connect

    Ahn, Sunyoung; Kim, Hyun Jeong; Chi, Sung-Gil; Park, Heonyong

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer FRNK domain is recruited into focal adhesion (FA), controlling endothelial cell adhesion. Black-Right-Pointing-Pointer XIAP binds the FRNK domain of FAK. Black-Right-Pointing-Pointer XIAP inhibits recruitment of FRNK into Fas and FRNK-promoted cell adhesion. Black-Right-Pointing-Pointer XIAP plays a key role in vascular functions of FRNK or FRNK domain-mediated vascular functions of FAK. -- Abstract: In endothelial cells, focal adhesion kinase (FAK) regulates cell proliferation, migration, adhesion, and shear-stimulated activation of MAPK. We recently found that FAK is recruited into focal adhesion (FA) sites through interactions with XIAP (X-chromosome linked inhibitor of apoptosis protein) and activated by Src kinase in response to shear stress. In this study, we examined which domain(s) of FAK is(are) important for various vascular functions such as FA recruiting, XIAP-binding and shear stress-stimulated ERK activation. Through a series of experiments, we determined that the FRNK domain is recruited into FA sites and promotes endothelial cell adhesion. Interestingly, XIAP knockdown was shown to reduce FA recruitment of FRNK and the cell adhesive effect of FRNK. In addition, we found that XIAP interacts with FRNK, suggesting cross-talk between XIAP and FRNK. We also demonstrated that FRNK inhibits endothelial cell migration and shear-stimulated ERK activation. These inhibitory effects of FRNK were reversed by XIAP knockdown. Taken together, we can conclude that XIAP plays a key role in vascular functions of FRNK or FRNK domain-mediated vascular functions of FAK.

  11. Identification of endothelial antigens relevant to transplant coronary artery disease from a human endothelial cell cDNA expression library.

    PubMed

    Ationu, A

    1998-06-01

    Accelerated transplant coronary artery disease (TxCAD) results in increased expression of antiendothelial antibodies whose target antigens remain largely unidentified. One of these endothelial antigens has been identified as vimentin, a cytoskeletal protein present in cells of the blood vessel walls. In the present study, SDS-PAGE and Western blot analysis of human endothelial cell (EAHy 926) lysates probed with sera from a TxCAD patient were used to confirm immunoreactivity of antiendothelial antibodies towards several endothelial proteins. To further elucidate the identity of these putative antigens, a human endothelial cell (EAHy 926) cDNA expression library was immunoscreened with serum obtained from a TxCAD patient. Two positive cDNA clones were identified by partial nucleotide sequence analysis and GenBank/EMBL database searches for homology as the 85 kDa human CD36 antigen (a cell surface glycoprotein expressed in various cells including epithelial and endothelial cells) and a 50 kDa keratin-like protein (a member of the intermediate filament protein expressed in epithelial cells). These results are the first to demonstrate that human CD36 antigen and a keratin-like protein may be additional target proteins for the anti-endothelial antibodies associated with TxCAD. PMID:9852639

  12. Nitrative Stress Participates in Endothelial Progenitor Cell Injury in Hyperhomocysteinemia

    PubMed Central

    Dong, Yu; Sun, Qi; Liu, Teng; Wang, Huanyuan; Jiao, Kun; Xu, Jiahui; Liu, Xin; Liu, Huirong; Wang, Wen

    2016-01-01

    In order to investigate the role of nitrative stress in vascular endothelial injury in hyperhomocysteinemia (HHcy), thirty healthy adult female Wistar rats were randomly divided into three groups: control, hyperhomocysteinemia model, and hyperhomocysteinemia with FeTMPyP (peroxynitrite scavenger) treatment. The endothelium-dependent dilatation of thoracic aorta in vitro was determined by response to acetylcholine (ACh). The histological changes in endothelium were assessed by HE staining and scanning electron microscopy (SEM). The expression of 3-nitrotyrosine (NT) in thoracic aorta was demonstrated by immunohistochemistry and immunofluorescence, and the number of circulating endothelial progenitor cells (EPCs) was quantified by flow cytometry. Hyperhomocysteinemia caused significant endothelial injury and dysfunction including vasodilative and histologic changes, associated with higher expression of NT in thoracic aorta. FeTMPyP treatment reversed these injuries significantly. Further, the effect of nitrative stress on cultured EPCs in vitro was investigated by administering peroxynitrite donor (3-morpholino-sydnonimine, SIN-1) and peroxynitrite scavenger (FeTMPyP). The roles of nitrative stress on cell viability, necrosis and apoptosis were evaluated with 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium (MTT) assay, lactate dehydrogenase (LDH) release assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, respectively. Also, the phospho-eNOS expression and tube formation in Matrigel of cultured EPCs was detected. Our data showed that the survival of EPCs was much lower in SIN-1 group than in vehicle group, both the apoptosis and necrosis of EPCs were much more severe, and the p-eNOS expression and tube formation in Matrigel were obviously declined. Subsequent pretreatment with FeTMPyP reversed these changes. Further, pretreatment with FeTMPyP reversed homocysteine-induced EPC injury. In conclusion, this study indicates that

  13. Nitrative Stress Participates in Endothelial Progenitor Cell Injury in Hyperhomocysteinemia.

    PubMed

    Dong, Yu; Sun, Qi; Liu, Teng; Wang, Huanyuan; Jiao, Kun; Xu, Jiahui; Liu, Xin; Liu, Huirong; Wang, Wen

    2016-01-01

    In order to investigate the role of nitrative stress in vascular endothelial injury in hyperhomocysteinemia (HHcy), thirty healthy adult female Wistar rats were randomly divided into three groups: control, hyperhomocysteinemia model, and hyperhomocysteinemia with FeTMPyP (peroxynitrite scavenger) treatment. The endothelium-dependent dilatation of thoracic aorta in vitro was determined by response to acetylcholine (ACh). The histological changes in endothelium were assessed by HE staining and scanning electron microscopy (SEM). The expression of 3-nitrotyrosine (NT) in thoracic aorta was demonstrated by immunohistochemistry and immunofluorescence, and the number of circulating endothelial progenitor cells (EPCs) was quantified by flow cytometry. Hyperhomocysteinemia caused significant endothelial injury and dysfunction including vasodilative and histologic changes, associated with higher expression of NT in thoracic aorta. FeTMPyP treatment reversed these injuries significantly. Further, the effect of nitrative stress on cultured EPCs in vitro was investigated by administering peroxynitrite donor (3-morpholino-sydnonimine, SIN-1) and peroxynitrite scavenger (FeTMPyP). The roles of nitrative stress on cell viability, necrosis and apoptosis were evaluated with 3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium (MTT) assay, lactate dehydrogenase (LDH) release assay and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, respectively. Also, the phospho-eNOS expression and tube formation in Matrigel of cultured EPCs was detected. Our data showed that the survival of EPCs was much lower in SIN-1 group than in vehicle group, both the apoptosis and necrosis of EPCs were much more severe, and the p-eNOS expression and tube formation in Matrigel were obviously declined. Subsequent pretreatment with FeTMPyP reversed these changes. Further, pretreatment with FeTMPyP reversed homocysteine-induced EPC injury. In conclusion, this study indicates that

  14. Coordinated Molecular Cross-Talk between Staphylococcus aureus, Endothelial Cells and Platelets in Bloodstream Infection.

    PubMed

    Garciarena, Carolina D; McHale, Tony M; Watkin, Rebecca L; Kerrigan, Steven W

    2015-01-01

    Staphylococcus aureus is an opportunistic pathogen often carried asymptomatically on the human body. Upon entry to the otherwise sterile environment of the cardiovascular system, S. aureus can lead to serious complications resulting in organ failure and death. The success of S. aureus as a pathogen in the bloodstream is due to its ability to express a wide array of cell wall proteins on its surface that recognise host receptors, extracellular matrix proteins and plasma proteins. Endothelial cells and platelets are important cells in the cardiovascular system and are a major target of bloodstream infection. Endothelial cells form the inner lining of a blood vessel and provide an antithrombotic barrier between the vessel wall and blood. Platelets on the other hand travel throughout the cardiovascular system and respond by aggregating around the site of injury and initiating clot formation. Activation of either of these cells leads to functional dysregulation in the cardiovascular system. In this review, we will illustrate how S. aureus establish intimate interactions with both endothelial cells and platelets leading to cardiovascular dysregulation. PMID:26690226

  15. Coordinated Molecular Cross-Talk between Staphylococcus aureus, Endothelial Cells and Platelets in Bloodstream Infection

    PubMed Central

    Garciarena, Carolina D.; McHale, Tony M.; Watkin, Rebecca L.; Kerrigan, Steven W.

    2015-01-01

    Staphylococcus aureus is an opportunistic pathogen often carried asymptomatically on the human body. Upon entry to the otherwise sterile environment of the cardiovascular system, S. aureus can lead to serious complications resulting in organ failure and death. The success of S. aureus as a pathogen in the bloodstream is due to its ability to express a wide array of cell wall proteins on its surface that recognise host receptors, extracellular matrix proteins and plasma proteins. Endothelial cells and platelets are important cells in the cardiovascular system and are a major target of bloodstream infection. Endothelial cells form the inner lining of a blood vessel and provide an antithrombotic barrier between the vessel wall and blood. Platelets on the other hand travel throughout the cardiovascular system and respond by aggregating around the site of injury and initiating clot formation. Activation of either of these cells leads to functional dysregulation in the cardiovascular system. In this review, we will illustrate how S. aureus establish intimate interactions with both endothelial cells and platelets leading to cardiovascular dysregulation. PMID:26690226

  16. Perfusion and Characterization of an Endothelial Cell-Seeded Modular Tissue Engineered Construct Formed in a Microfluidic Remodeling Chamber

    PubMed Central

    Khan, Omar F.

    2010-01-01

    Tissue engineered constructs containing tortuous endothelial cell-lined perfusion channels were formed by randomly assembling endothelial cell-seeded submillimeter-sized collagen cylinders (modules) into a microfluidic perfusion chamber. The interconnected void space produced by random module packing created flow channels that were lined with endothelial cells. The effect of perfusion (0.5 mL min−1, Re* = 14.36 and shear stress = 0.64 dyn cm−2) through the tortuous channels on construct remodeling and endothelium quiescence was studied. Over time, modules fused at their points of contact and as they contracted, decreased the internal void space, which reduced the overall perfusion through the construct. As compared to static controls, perfusion caused a transient increase in activation (ICAM-1 and VCAM-1 expression) after 1 hour followed by a decrease after 24 hours. Proliferation (by BrdU) was reduced significantly, while KLF2, which is upregulated with atheroprotective laminar shear stress, was upregulated significantly after 24 hours. VE-cadherin became discontinuous and was significantly downregulated after 24 hours, which was likely caused by the dismantling of the endothelial cell adherens junctions during remodeling. Collectively, these outcomes suggest that flow through the construct did not drive the endothelial cells towards an inflamed, “atherosclerotic like” disturbed flow pathology. PMID:20678792

  17. Time analysis of corneal endothelial cell density after cataract extraction.

    PubMed

    Galin, M A; Lin, L L; Fetherolf, E; Obstbaum, S A; Sugar, A

    1979-07-01

    Serial endothelial photographs were taken preoperatively and postoperatively in 200 eyes; 111 eyes contained a Rayner iris clip lens, 54 eyes contained a Fyodorov Sputnik lens, and 35 eyes had no lens. Central endothelial cell density was changed in all instances, with counts in implanted eyes declining 25 to 30%, and in nonimplanted eyes 10 to 15%. In both instances, the decline essentially ceased at about three months. The cause of the greater decline in implanted eyes appeared to be mechanical and subsequent cell loss after the 90-day period was virtually equal for the two groups. Methods that may be used to alter the difference in cell density occurring with implantation are best analyzed by using the 90-day period data for comparison. PMID:464015

  18. Suprabasin as a novel tumor endothelial cell marker.

    PubMed

    Alam, Mohammad T; Nagao-Kitamoto, Hiroko; Ohga, Noritaka; Akiyama, Kosuke; Maishi, Nako; Kawamoto, Taisuke; Shinohara, Nobuo; Taketomi, Akinobu; Shindoh, Masanobu; Hida, Yasuhiro; Hida, Kyoko

    2014-12-01

    Recent studies have reported that stromal cells contribute to tumor progression. We previously demonstrated that tumor endothelial cells (TEC) characteristics were different from those of normal endothelial cells (NEC). Furthermore, we performed gene profile analysis in TEC and NEC, revealing that suprabasin (SBSN) was upregulated in TEC compared with NEC. However, its role in TEC is still unknown. Here we showed that SBSN expression was higher in isolated human and mouse TEC than in NEC. SBSN knockdown inhibited the migration and tube formation ability of TEC. We also showed that the AKT pathway was a downstream factor of SBSN. These findings suggest that SBSN is involved in the angiogenic potential of TEC and may be a novel TEC marker. PMID:25283635

  19. Nitrones reverse hyperglycemia-induced endothelial dysfunction in bovine aortic endothelial cells.

    PubMed

    Headley, Colwyn A; DiSilvestro, David; Bryant, Kelsey E; Hemann, Craig; Chen, Chun-An; Das, Amlan; Ziouzenkova, Ouliana; Durand, Grégory; Villamena, Frederick A

    2016-03-15

    Hyperglycemia has been implicated in the development of endothelial dysfunction through heightened ROS production. Since nitrones reverse endothelial nitric oxide synthase (eNOS) dysfunction, increase antioxidant enzyme activity, and suppress pro-apoptotic signaling pathway and mitochondrial dysfunction from ROS-induced toxicity, the objective of this study was to determine whether nitrone spin traps DMPO, PBN and PBN-LA were effective at duplicating these effects and improving glucose uptake in an in vitro model of hyperglycemia-induced dysfunction using bovine aortic endothelial cells (BAEC). BAEC were cultured in DMEM medium with low (5.5mM glucose, LG) or high glucose (50mM, HG) for 14 days to model in vivo hyperglycemia as experienced in humans with metabolic disease. Improvements in cell viability, intracellular oxidative stress, NO and tetrahydrobiopterin (BH4)​ levels, mitochondrial membrane potential, glucose transport, and activity of antioxidant enzymes were measured from single treatment of BAEC with nitrones for 24h after hyperglycemia. Chronic hyperglycemia significantly increased intracellular ROS by 50%, decreased cell viability by 25%, reduced NO bioavailability by 50%, and decreased (BH4) levels by 15% thereby decreasing NO production. Intracellular glucose transport and superoxide dismutase (SOD) activity were also decreased by 50% and 25% respectively. Nitrone (PBN and DMPO, 50 μM) treatment of BAEC grown in hyperglycemic conditions resulted in the normalization of outcome measures except for SOD and catalase activities. Our findings demonstrate that the nitrones reverse the deleterious effects of hyperglycemia in BAEC. We believe that in vivo testing of these nitrone compounds in models of cardiometabolic disease is warranted. PMID:26774452

  20. Mesenchymal Stromal Cells Protect Endothelial Cells from Cytotoxic T Lymphocyte-Induced Lysis.

    PubMed

    Cahill, E F; Sax, T; Hartmann, I; Haffner, S; Holler, E; Holler, B; Huss, R; Günther, C; Parolini, O; Kolch, W; Eissner, G

    2016-09-01

    The integrity of the vasculature plays an important role in the success of allogeneic organ and haematopoietic stem cell transplantation. Endothelial cells (EC) have previously been shown to be the target of activated cytotoxic T lymphocytes (CTL) resulting in extensive cell lysis. Mesenchymal stromal cells (MSC) are multipotent cells which can be isolated from multiple sites, each demonstrating immunomodulatory capabilities. They are explored herein for their potential to protect EC from CTL-targeted lysis. CD8(+) T cells isolated from human PBMC were stimulated with mitotically inactive cells of a human microvascular endothelial cell line (CDC/EU.HMEC-1, further referred to as HMEC) for 7 days. Target HMEC were cultured in the presence or absence of MSC for 24 h before exposure to activated allogeneic CTL for 4 h. EC were then analysed for cytotoxic lysis by flow cytometry. Culture of HMEC with MSC in the efferent immune phase (24 h before the assay) led to a decrease in HMEC lysis. This lysis was determined to be MHC Class I restricted linked and further analysis suggested that MSC contact is important in abrogation of lysis, as protection is reduced where MSC are separated in transwell experiments. The efficacy of multiple sources of MSC was also confirmed, and the collaborative effect of MSC and the endothelium protective drug defibrotide were determined, with defibrotide enhancing the protection provided by MSC. These results support the use of MSC as an adjuvant cellular therapeutic in transplant medicine, alone or in conjunction with EC protective agents such as defibrotide. PMID:27384426

  1. Bisphenol A Disrupts Transcription and Decreases Viability in Aging Vascular Endothelial Cells

    PubMed Central

    Ribeiro-Varandas, Edna; Pereira, H. Sofia; Monteiro, Sara; Neves, Elsa; Brito, Luísa; Boavida Ferreira, Ricardo; Viegas, Wanda; Delgado, Margarida

    2014-01-01

    Bisphenol A (BPA) is a widely utilized endocrine disruptor capable of mimicking endogenous hormones, employed in the manufacture of numerous consumer products, thereby interfering with physiological cellular functions. Recent research has shown that BPA alters epigenetic cellular mechanisms in mammals and may be correlated to enhanced cellular senescence. Here, the effects of BPA at 10 ng/mL and 1 µg/mL, concentrations found in human samples, were analyzed on HT29 human colon adenocarcinona cell line and Human Umbilical Vein Endothelial Cells (HUVEC). Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) transcriptional analysis of the Long Interspersed Element-1 (LINE-1) retroelement showed that BPA induces global transcription deregulation in both cell lines, although with more pronounced effects in HUVEC cells. Whereas there was an increase in global transcription in HT29 exclusively after 24 h of exposure, this chemical had prolonged effects on HUVEC. Immunoblotting revealed that this was not accompanied by alterations in the overall content of H3K9me2 and H3K4me3 epigenetic marks. Importantly, cell viability assays and transcriptional analysis indicated that prolonged BPA exposure affects aging processes in senescent HUVEC. To our knowledge this is the first report that BPA interferes with senescence in primary vascular endothelial cells, therefore, suggesting its association to the etiology of age-related human pathologies, such as atherosclerosis. PMID:25207595

  2. [Expression and function of receptors for advanced glycation end products in bovine corneal endothelial cells].

    PubMed

    Kaji, Yuichi

    2005-11-01

    Corneal endothelial cell loss is a change that occurs with age, but its mechanism is still unclear. We postulated that interaction between advanced glycation end product(AGE) and its receptors is implicated in the corneal endothelial cell loss with age. We investigated the expression of AGE receptors: receptors for AGE(RAGE) and galectin-3 in bovine corneal endothelial cells by reverse transcription-polymerase chain reaction(RT-PCR) and immunohistochemistry. In addition, we investigated the effect of AGE on the cultured corneal endothelial cells. Expression of RAGE and galectin-3 was detected in bovine corneal endothelial cells. Galectin-3 was important in the internalization of AGE. In contrast, RAGE was important in the generation of reactive oxygen species and induction of apoptosis. Based on these data, the interaction of AGE in aqueous humor and AGE receptors expressed on the corneal endothelial cells was speculated to have a role in the corneal endothelial cell loss with age. PMID:16363662

  3. Brain microvascular endothelial cell transplantation ameliorates ischemic white matter damage.

    PubMed

    Puentes, Sandra; Kurachi, Masashi; Shibasaki, Koji; Naruse, Masae; Yoshimoto, Yuhei; Mikuni, Masahiko; Imai, Hideaki; Ishizaki, Yasuki

    2012-08-21

    Ischemic insults affecting the internal capsule result in sensory-motor disabilities which adversely affect the patient's life. Cerebral endothelial cells have been reported to exert a protective effect against brain damage, so the transplantation of healthy endothelial cells might have a beneficial effect on the outcome of ischemic brain damage. In this study, endothelin-1 (ET-1) was injected into the rat internal capsule to induce lacunar infarction. Seven days after ET-1 injection, microvascular endothelial cells (MVECs) were transplanted into the internal capsule. Meningeal cells or 0.2% bovine serum albumin-Hank's balanced salt solution were injected as controls. Two weeks later, the footprint test and histochemical analysis were performed. We found that MVEC transplantation improved the behavioral outcome based on recovery of hind-limb rotation angle (P<0.01) and induced remyelination (P<0.01) compared with the control groups. Also the inflammatory response was repressed by MVEC transplantation, judging from fewer ED-1-positive activated microglial cells in the MVEC-transplanted group than in the other groups. Elucidation of the mechanisms by which MVECs ameliorate ischemic damage of the white matter may provide important information for the development of effective therapies for white matter ischemia. PMID:22771710

  4. Circulating Progenitor and Mature Endothelial Cells in Deep Vein Thrombosis

    PubMed Central

    Alessio, Aline M; Beltrame, Miriam P; Nascimento, Mariane C Flores; Vicente, Cristina P; de Godoy, Juliana AP; Silva, Junia CR Santos; Bittar, Luis Fernando; Lorand-Metze, Irene; de Paula, Erich V; Annichino-Bizzacchi, Joyce M

    2013-01-01

    Introduction: Mature circulating endothelial cells (CEC) and circulating endothelial progenitor cells (EPC) have been described in several conditions associated with endothelial injury. Their role in deep vein thrombosis (DVT) has not been previously evaluated. Patients and Methods: In this pilot study we evaluated the time course of CEC and EPC release after vena cava experimental DVT in mice, using the FeCl3 model. We also evaluated their presence in patients with DVT at different phases of the disease (acute and chronic phase). CEC and EPC were evaluated by Flow Cytometry. Results: In mice, both CEC and EPC were increased 24 hours after DVT induction, peaking 48 hours thereafter. After 72 hours, CEC counts decreased sharply, whereas EPC counts decreased less substantially. In DVT patients we observed a significant increase in CEC counts immediately after DVT compared to healthy individuals. Patients with chronic disease also presented a significant elevation of these cell count. In a subgroup of patients for whom serial samples were available, CEC counts decreased significantly after 9-15 months of the acute event. Conclusions: Our results suggest the participation of these cells in the reparative processes that follows DVT, both at immediate and late time-points. The different kinetics of CEC and EPC release in experimental DVT suggests a heterogeneous role for these cells in the reparative events after DVT. PMID:24155660

  5. Endothelial cells derived from embryonic stem cells respond to cues from topographical surface patterns

    PubMed Central

    2013-01-01

    The generation of micro- and nano-topography similar to those found in the extra cellular matrix of three-dimensional tissues is one technique used to recapitulate the cell-tissue physiology found in the native tissues. Despite the fact that ample studies have been conducted on the physiological significance of endothelial cells alignment parallel to shear stress, as this is the normal physiologic arrangement for healthy arterial EC, very few studies have examined the use of topographical signals to initiate endothelial cell alignment. Here, we have examined the ability for our mouse embryonic stem cell-derived endothelial cells (ESC-EC) to align on various microchip topographical systems. Briefly, we generated metal molds with ‘wrinkled’ topography using 1) 15 nm and 2) 30 nm of gold coating on the pre-strained polystryene (PS) sheets. After thermal-induced shrinkage of the PS sheets, polydimethylsiloxane (PDMS) microchips were then generated from the wrinkled molds. Using similar Shrink™-based technology, 3) larger selectively crazed acetone-etched lines in the PS sheets, and 4) fully crazed acetone-treated PS sheets of stochastic topographical morphology were also generated. The 15 nm and 30 nm gold coating generated ‘wrinkles’ of uniaxial anisotropic channels at nano-scaled widths while the crazing generated micron-sized channels. The ESC-EC were able to respond and align on the 320 nm, 510 nm, and the acetone-etched 10.5 μm channels, but not on the fully ‘crazed’ topographies. Moreover, the ESC-EC aligned most robustly on the wrinkles, and preferentially to ridge edges on the 10.5 μm-sized channels. The ability to robustly align EC on topographical surfaces enables a variety of controlled physiological studies of EC-EC and EC-ECM contact guidance, as well as having potential applications for the rapid endothelialization of stents and vascular grafts. PMID:23819656

  6. Endothelial cells derived from embryonic stem cells respond to cues from topographical surface patterns.

    PubMed

    Hatano, Rachel; Mercurio, Kevin; Luna, Jesus Isaac; Glaser, Drew E; Leppert, Valerie J; McCloskey, Kara E

    2013-01-01

    The generation of micro- and nano-topography similar to those found in the extra cellular matrix of three-dimensional tissues is one technique used to recapitulate the cell-tissue physiology found in the native tissues. Despite the fact that ample studies have been conducted on the physiological significance of endothelial cells alignment parallel to shear stress, as this is the normal physiologic arrangement for healthy arterial EC, very few studies have examined the use of topographical signals to initiate endothelial cell alignment. Here, we have examined the ability for our mouse embryonic stem cell-derived endothelial cells (ESC-EC) to align on various microchip topographical systems. Briefly, we generated metal molds with 'wrinkled' topography using 1) 15 nm and 2) 30 nm of gold coating on the pre-strained polystryene (PS) sheets. After thermal-induced shrinkage of the PS sheets, polydimethylsiloxane (PDMS) microchips were then generated from the wrinkled molds. Using similar Shrink™-based technology, 3) larger selectively crazed acetone-etched lines in the PS sheets, and 4) fully crazed acetone-treated PS sheets of stochastic topographical morphology were also generated. The 15 nm and 30 nm gold coating generated 'wrinkles' of uniaxial anisotropic channels at nano-scaled widths while the crazing generated micron-sized channels. The ESC-EC were able to respond and align on the 320 nm, 510 nm, and the acetone-etched 10.5 μm channels, but not on the fully 'crazed' topographies. Moreover, the ESC-EC aligned most robustly on the wrinkles, and preferentially to ridge edges on the 10.5 μm-sized channels. The ability to robustly align EC on topographical surfaces enables a variety of controlled physiological studies of EC-EC and EC-ECM contact guidance, as well as having potential applications for the rapid endothelialization of stents and vascular grafts. PMID:23819656

  7. Assaying endothelial-mural cell interactions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent studies in genetically malleable embryonic model systems have enabled the identification of factors required for blood vessel formation. However, it is not possible in most in vivo systems to dissect carefully the exact cellular behaviours, as well as cell-cell and cell-matrix interactions t...

  8. Hypoxia-Induced Alternative Splicing in Endothelial Cells

    PubMed Central

    Weigand, Julia E.; Boeckel, Jes-Niels; Gellert, Pascal; Dimmeler, Stefanie

    2012-01-01

    Background Adaptation to low oxygen by changing gene expression is vitally important for cell survival and tissue development. The sprouting of new blood vessels, initiated from endothelial cells, restores the oxygen supply of ischemic tissues. In contrast to the transcriptional response induced by hypoxia, which is mainly mediated by members of the HIF family, there are only few studies investigating alternative splicing events. Therefore, we performed an exon array for the genome-wide analysis of hypoxia-related changes of alternative splicing in endothelial cells. Methodology/Principal findings Human umbilical vein endothelial cells (HUVECs) were incubated under hypoxic conditions (1% O2) for 48 h. Genome-wide transcript and exon expression levels were assessed using the Affymetrix GeneChip Human Exon 1.0 ST Array. We found altered expression of 294 genes after hypoxia treatment. Upregulated genes are highly enriched in glucose metabolism and angiogenesis related processes, whereas downregulated genes are mainly connected to cell cycle and DNA repair. Thus, gene expression patterns recapitulate known adaptations to low oxygen supply. Alternative splicing events, until now not related to hypoxia, are shown for nine genes: six which are implicated in angiogenesis-mediated cytoskeleton remodeling (cask, itsn1, larp6, sptan1, tpm1 and robo1); one, which is involved in the synthesis of membrane-anchors (pign) and two universal regulators of gene expression (cugbp1 and max). Conclusions/Significance For the first time, this study investigates changes in splicing in the physiological response to hypoxia on a genome-wide scale. Nine alternative splicing events, until now not related to hypoxia, are reported, considerably expanding the information on splicing changes due to low oxygen supply. Therefore, this study provides further knowledge on hypoxia induced gene expression changes and presents new starting points to study the hypoxia adaptation of endothelial cells

  9. Fluid shear, intercellular stress, and endothelial cell alignment

    PubMed Central

    Steward, Robert; Tambe, Dhananjay; Hardin, C. Corey; Krishnan, Ramaswamy

    2015-01-01

    Endothelial cell alignment along the direction of laminar fluid flow is widely understood to be a defining morphological feature of vascular homeostasis. While the role of associated signaling and structural events have been well studied, associated intercellular stresses under laminar fluid shear have remained ill-defined and the role of these stresses in the alignment process has remained obscure. To fill this gap, we report here the tractions as well as the complete in-plane intercellular stress fields measured within the human umbilical vein endothelial cell (HUVEC) monolayer subjected to a steady laminar fluid shear of 1 Pa. Tractions, intercellular stresses, as well as their time course, heterogeneity, and anisotropy, were measured using monolayer traction microscopy and monolayer stress microscopy. Prior to application of laminar fluid flow, intercellular stresses were largely tensile but fluctuated dramatically in space and in time (317 ± 122 Pa). Within 12 h of the onset of laminar fluid flow, the intercellular stresses decreased substantially but continued to fluctuate dramatically (142 ± 84 Pa). Moreover, tractions and intercellular stresses aligned strongly and promptly (within 1 h) along the direction of fluid flow, whereas the endothelial cell body aligned less strongly and substantially more slowly (12 h). Taken together, these results reveal that steady laminar fluid flow induces prompt reduction in magnitude and alignment of tractions and intercellular stress tensor components followed by the retarded elongation and alignment of the endothelial cell body. Appreciably smaller intercellular stresses supported by cell-cell junctions logically favor smaller incidence of gap formation and thus improved barrier integrity. PMID:25652451

  10. A microarray analysis of two distinct lymphatic endothelial cell populations

    PubMed Central

    Schweighofer, Bernhard; Rohringer, Sabrina; Pröll, Johannes; Holnthoner, Wolfgang

    2015-01-01

    We have recently identified lymphatic endothelial cells (LECs) to form two morphologically different populations, exhibiting significantly different surface protein expression levels of podoplanin, a major surface marker for this cell type. In vitro shockwave treatment (IVSWT) of LECs resulted in enrichment of the podoplaninhigh cell population and was accompanied by markedly increased cell proliferation, as well as 2D and 3D migration. Gene expression profiles of these distinct populations were established using Affymetrix microarray analyses. Here we provide additional details about our dataset (NCBI GEO accession number GSE62510) and describe how we analyzed the data to identify differently expressed genes in these two LEC populations. PMID:26484194

  11. Acetylbritannilactone Modulates Vascular Endothelial Growth Factor Signaling and Regulates Angiogenesis in Endothelial Cells

    PubMed Central

    Zhao, Jingshan; Niu, Honglin; Li, Aiying; Nie, Lei

    2016-01-01

    The present study was conducted to determine the effects of 1-O-acetylbritannilactone (ABL), a compound extracted from Inula britannica L., on vascular endothelial growth factor (VEGF) signaling and angiogenesis in endothelial cells (ECs). We showed that ABL promotes VEGF-induced cell proliferation, growth, migration, and tube formation in cultured human ECs. Furthermore, the modulatory effect of ABL on VEGF-induced Akt, MAPK p42/44, and p38 phosphorylation, as well as on upstream VEGFR-2 phosphorylation, were associated with VEGF-dependent Matrigel angiogenesis in vivo. In addition, animals treated with ABL (26 mg/kg/day) recovered blood flow significantly earlier than control animals, suggesting that ABL affects ischemia-mediated angiogenesis and arteriogenesis in vivo. Finally, we demonstrated that ABL strongly reduced the levels of VEGFR-2 on the cell surface, enhanced VEGFR-2 endocytosis, which consistent with inhibited VE-cadherin, a negative regulator of VEGF signaling associated with VEGFR-2 complex formation, but did not alter VE-cadherin or VEGFR-2 expression in ECs. Our results suggest that ABL may serve as a novel therapeutic intervention for various cardiovascular diseases, including chronic ischemia, by regulating VEGF signaling and modulating angiogenesis. PMID:26863518

  12. Adhesion assays of endothelial cells on nanopatterned surfaces within a microfluidic channel.

    PubMed

    Hwang, Se Yon; Kwon, Keon Woo; Jang, Kyung-Jin; Park, Min Cheol; Lee, Jeong Sang; Suh, Kahp Y

    2010-04-01

    We present a simple analytical method to measure adhesion of human umbilical vein endothelial cells (HUVECs) and calf pulmonary artery endothelial cells (CPAEs) using nanopatterned, biodegradable poly(lactic-co-glycolic acid) (PLGA) surfaces for potential applications to artificial tissue-engineered blood vessel. Various nanostructured PLGA surfaces (350 nm wide ridges/350 nm grooves, 350 nm ridges/700 nm grooves, 350 nm ridges/1750 nm grooves, 700 nm ridges/350 nm grooves, 1050 nm ridges/350 nm grooves, 1750 nm ridges/350 nm grooves) and flat (unpatterned) surfaces were fabricated on the bottom of polydimethylsiloxane (PDMS) microfluidic channel of 2 mm width and 60 microm height by using thermal imprinting and irreversible channel bonding. To measure adhesion strength of HUVECs and CPAEs, the cells were exposed to a range of shear stress (12, 40, and 80 dyn/cm(2)) within the channels for 20 min after a preculture for 3 days and the remaining cells were counted under each condition. The highest adhesion strength was found on the surface of 700 nm wide ridges, 350 nm wide grooves for both cell types. The enhanced adhesion on nanopatterned surfaces can be attributed to two aspects: (i) contact guidance along the line direction and (ii) clustered focal adhesions. In particular, the contact guidance induced cell alignment along the line directions, which in turn lowers wall shear stress applied to the cell surface, as supported by a simple hydrodynamic model based on cell morphology. PMID:20218573

  13. Endothelin B receptors on human endothelial and smooth-muscle cells show equivalent binding pharmacology.

    PubMed

    Flynn, M A; Haleen, S J; Welch, K M; Cheng, X M; Reynolds, E E

    1998-07-01

    We have described the pharmacologic profiles of endothelin B receptors in human endothelial cells and vascular and nonvascular smooth-muscle cells. First, by amplifying endothelin B receptor numbers through the use of phosphoramidon and intact cell-binding techniques, we demonstrated the presence of these receptors in human umbilical vein endothelial cells (100% endothelin B receptors), human aortic smooth-muscle cells (22% endothelin B, 78% endothelin A receptors), and human bronchial smooth-muscle cells (55% endothelin B, 45% endothelin A receptors) by using [125I]-endothelin-1 radioligand binding. The typical binding profiles of the endothelin B receptors were established through competition binding curve analysis with endothelin-1, endothelin-3, sarafotoxin 6c, and the endothelin A receptor-selective antagonist BQ-123. In the presence of BQ-123, a diverse group of antagonists, including PD 142893, BQ-788, SB 209670, and Ro 47-0203, were used to probe for binding differences indicative of multiple endothelin B-receptor subtypes. The results indicate a rank order of potency for the antagonists of BQ-788 > SB 209670 > PD 142893 > Ro 47-0203 for each cell line, and that between any of these human cell lines, measurements of [125I]-endothelin-1-binding antagonism for each of the four test compounds differed by less than twofold. Although this study cannot discount the possibility of more than one endothelin B-receptor subtype in humans, it does indicate that these tissues express receptors that show equivalent binding pharmacology. PMID:9676729

  14. Haemodynamic and extracellular matrix cues regulate the mechanical phenotype and stiffness of aortic endothelial cells

    PubMed Central

    Collins, Caitlin; Osborne, Lukas D.; Guilluy, Christophe; Chen, Zhongming; O’Brien, E Tim; Reader, John S.; Burridge, Keith; Superfine, Richard; Tzima, Ellie

    2014-01-01

    Endothelial cell (ECs) lining blood vessels express many mechanosensors, including platelet endothelial cell adhesion molecule-1 (PECAM-1), that convert mechanical force to biochemical signals. While it is accepted that mechanical stresses and the mechanical properties of ECs regulate vessel health, the relationship between force and biological response remains elusive. Here we show that ECs integrate mechanical forces and extracellular matrix (ECM) cues to modulate their own mechanical properties. We demonstrate that the ECM influences EC response to tension on PECAM-1. ECs adherent on collagen display divergent stiffening and focal adhesion growth compared to ECs on fibronectin. This is due to PKA-dependent serine phosphorylation and inactivation of RhoA. PKA signaling regulates focal adhesion dynamics and EC compliance in response to shear stress in vitro and in vivo. Our study identifies a ECM-specific, mechanosensitive signaling pathway that regulates EC compliance and may serve as an atheroprotective mechanism maintains blood vessel integrity in vivo. PMID:24917553

  15. Relationship between Microtubule Network Structure and Intracellular Transport in Cultured Endothelial Cells Affected by Shear Stress

    NASA Astrophysics Data System (ADS)

    Kudo, Susumu; Ikezawa, Kenji; Ikeda, Mariko; Tanishita, Kazuo

    Endothelial cells (ECs) that line the inner surface of blood vessels are barriers to the transport of various substances into or from vessel walls, and are continuously exposed to shear stress induced by blood flow in vivo. Shear stress affects the cytoskeleton (e.g., microtubules, microfilaments, intermediate filaments), and affects the transport of macromolecules. Here, the relationship between the microtubule network structure and this transport process for albumin uptake within cultured aortic endothelial cells affected by shear stress was studied. Based on fluorescent images of albumin uptake obtained by using confocal laser scanning microscopy (CLSM), both the microtubule network and albumin uptake in ECs were disrupted by colchicine and were affected by shear stress loading.

  16. Mechanical Cell-Matrix Feedback Explains Pairwise and Collective Endothelial Cell Behavior In Vitro

    PubMed Central

    LaValley, Danielle J.; Reinhart-King, Cynthia A.; Merks, Roeland M. H.

    2014-01-01

    In vitro cultures of endothelial cells are a widely used model system of the collective behavior of endothelial cells during vasculogenesis and angiogenesis. When seeded in an extracellular matrix, endothelial cells can form blood vessel-like structures, including vascular networks and sprouts. Endothelial morphogenesis depends on a large number of chemical and mechanical factors, including the compliancy of the extracellular matrix, the available growth factors, the adhesion of cells to the extracellular matrix, cell-cell signaling, etc. Although various computational models have been proposed to explain the role of each of these biochemical and biomechanical effects, the understanding of the mechanisms underlying in vitro angiogenesis is still incomplete. Most explanations focus on predicting the whole vascular network or sprout from the underlying cell behavior, and do not check if the same model also correctly captures the intermediate scale: the pairwise cell-cell interactions or single cell responses to ECM mechanics. Here we show, using a hybrid cellular Potts and finite element computational model, that a single set of biologically plausible rules describing (a) the contractile forces that endothelial cells exert on the ECM, (b) the resulting strains in the extracellular matrix, and (c) the cellular response to the strains, suffices for reproducing the behavior of individual endothelial cells and the interactions of endothelial cell pairs in compliant matrices. With the same set of rules, the model also reproduces network formation from scattered cells, and sprouting from endothelial spheroids. Combining the present mechanical model with aspects of previously proposed mechanical and chemical models may lead to a more complete understanding of in vitro angiogenesis. PMID:25121971

  17. Endothelial Activation by Platelets from Sickle Cell Anemia Patients

    PubMed Central

    Proença-Ferreira, Renata; Brugnerotto, Ana Flávia; Garrido, Vanessa Tonin; Dominical, Venina Marcela; Vital, Daiana Morelli; Ribeiro, Marilene de Fátima Reis; dos Santos, Melissa Ercolin; Traina, Fabíola; Olalla-Saad, Sara T.; Costa, Fernando Ferreira; Conran, Nicola

    2014-01-01

    Sickle cell anemia (SCA) is associated with a hypercoagulable state. Increased platelet activation is reported in SCA and SCA platelets may present augmented adhesion to the vascular endothelium, potentially contributing to the vaso-occlusive process. We sought to observe the effects of platelets (PLTs) from healthy control (CON) individuals and SCA individuals on endothelial activation, in vitro. Human umbilical vein endothelial cells (HUVEC) were cultured, in the presence, or not, of washed PLTs from CON or steady-state SCA individuals. Supernatants were reserved for cytokine quantification, and endothelial adhesion molecules (EAM) were analyzed by flow cytometry; gene expressions of ICAM1 and genes of the NF-κB pathway were analyzed by qPCR. SCA PLTs were found to be more inflammatory, displaying increased adhesive properties, an increased production of IL-1β and a tendency towards elevated expressions of P-selectin and activated αIIbβ3. Following culture in the presence of SCA PLTs, HUVEC presented significant augmentations in the expressions of the EAM, ICAM-1 and E-selectin, as well as increased IL-8 production and increased ICAM1 and NFKB1 (encodes p50 subunit of NF-κB) gene expressions. Interestingly, transwell inserts abolished the effects of SCA PLTs on EAM expression. Furthermore, an inhibitor of the NF-κB pathway, BAY 11-7082, also prevented the induction of EAM expression on the HUVEC surface by SCA PLTs. In conclusion, we find further evidence to indicate that platelets circulate in an activated state in sickle cell disease and are capable of stimulating endothelial cell activation. This effect appears to be mediated by direct contact, or even adhesion, between the platelets and endothelial cells and via NFκB-dependent signaling. As such, activated platelets in SCD may contribute to endothelial activation and, therefore, to the vaso-occlusive process. Results provide further evidence to support the use of anti-platelet approaches in association

  18. Endothelial activation by platelets from sickle cell anemia patients.

    PubMed

    Proença-Ferreira, Renata; Brugnerotto, Ana Flávia; Garrido, Vanessa Tonin; Dominical, Venina Marcela; Vital, Daiana Morelli; Ribeiro, Marilene de Fátima Reis; dos Santos, Melissa Ercolin; Traina, Fabíola; Olalla-Saad, Sara T; Costa, Fernando Ferreira; Conran, Nicola

    2014-01-01

    Sickle cell anemia (SCA) is associated with a hypercoagulable state. Increased platelet activation is reported in SCA and SCA platelets may present augmented adhesion to the vascular endothelium, potentially contributing to the vaso-occlusive process. We sought to observe the effects of platelets (PLTs) from healthy control (CON) individuals and SCA individuals on endothelial activation, in vitro. Human umbilical vein endothelial cells (HUVEC) were cultured, in the presence, or not, of washed PLTs from CON or steady-state SCA individuals. Supernatants were reserved for cytokine quantification, and endothelial adhesion molecules (EAM) were analyzed by flow cytometry; gene expressions of ICAM1 and genes of the NF-κB pathway were analyzed by qPCR. SCA PLTs were found to be more inflammatory, displaying increased adhesive properties, an increased production of IL-1β and a tendency towards elevated expressions of P-selectin and activated αIIbβ3. Following culture in the presence of SCA PLTs, HUVEC presented significant augmentations in the expressions of the EAM, ICAM-1 and E-selectin, as well as increased IL-8 production and increased ICAM1 and NFKB1 (encodes p50 subunit of NF-κB) gene expressions. Interestingly, transwell inserts abolished the effects of SCA PLTs on EAM expression. Furthermore, an inhibitor of the NF-κB pathway, BAY 11-7082, also prevented the induction of EAM expression on the HUVEC surface by SCA PLTs. In conclusion, we find further evidence to indicate that platelets circulate in an activated state in sickle cell disease and are capable of stimulating endothelial cell activation. This effect appears to be mediated by direct contact, or even adhesion, between the platelets and endothelial cells and via NFκB-dependent signaling. As such, activated platelets in SCD may contribute to endothelial activation and, therefore, to the vaso-occlusive process. Results provide further evidence to support the use of anti-platelet approaches in association

  19. Enhancement of tumor necrosis factor-induced endothelial cell injury by cycloheximide

    SciTech Connect

    Nolop, K.B.; Ryan, U.S. )

    1990-08-01

    Tumor necrosis factor (TNF), a potent polypeptide mediator released by activated monocytes and macrophages, has a number of proinflammatory effects on endothelial cells. TNF is cytotoxic to tumor cells in vivo and in vitro, but TNF-induced toxicity to endothelial cells is less well established. We now report that cycloheximide (CHX), an inhibitor of protein synthesis, renders endothelial cells highly susceptible to TNF-induced lysis. TNF alone did not change the overall rate of protein synthesis by endothelial cells, whereas the addition of CHX completely abolished protein synthesis. Endothelial cells incubated in TNF alone in high concentrations (up to 1,000 U/ml) showed minimal rounding up and release of 51Cr. Likewise, CHX alone (5 micrograms/ml) had no significant effect on endothelial cell morphology and release of 51Cr. However, incubation of endothelial cells in both CHX and TNF caused injury in a dose-dependent manner. Morphological evidence of cell retraction, rounding, and detachment began within 2 h, but specific 51Cr release did not begin to rise until after 4 h. These changes were not observed when endothelial cells were incubated with TNF/CHX at 4 degrees C. The combination of TNF/CHX was lethal to all endothelial cells tested (bovine pulmonary artery, human umbilical vein, and human aorta), with human aortic cells showing the most pronounced changes. We conclude that healthy endothelial cells are resistant to TNF-induced lysis, but inhibition of their ability to make protein renders them highly susceptible.

  20. Volume changes of human endothelial cells induced by photodynamic treatment

    NASA Astrophysics Data System (ADS)

    Leunig, Andreas; Staub, Frank; Plesnila, Nick; Peters, Jurgen; Feyh, Jens; Gutmann, Ralph; Goetz, Alwin E.

    1996-01-01

    Photodynamic therapy (PDT) has shown promising results in treatment of malignant tumors. However, the mechanisms leading to tumor destruction during PDT are still not completely understood. In addition to effects on the microcirculation, damage to cellular structures has been observed following exposure of cells to PDT. A phenomenon preceding these events might possibly be cell swelling. We therefore studied the influence of treatment with Photofrin (PF) and laser light on volume changes and cell viability of endothelial cells. Endothelial cells were obtained from human umbilical cord veins (HUVEC) by an adaption of the method of Maruyama (1963). After subcultivation the cells were harvested and transferred as a cell suspension into a specially designed incubation chamber. Cells received either PF in concentrations of 1.5 or 3.0 (mu) g/ml and laser illumination (630 nm; 40 mW/cm2, 4 Joule), PF alone, or laser treatment only. Following start of PF incubation and after phototreatment cell samples were taken for volume measurements using flow cytometry and for studies of cellular morphology using scanning electron microscopy. Simultaneously, cell viability was monitored by the trypan blue exclusion test and colorimetric MTT assay. (abstract truncated)

  1. Syndecan-2 downregulation impairs angiogenesis in human microvascular endothelial cells

    SciTech Connect

    Noguer, Oriol Villena, Joan; Lorita, Jordi; Vilaro, Senen; Reina, Manuel

    2009-03-10

    The formation of new blood vessels, or angiogenesis, is a necessary process during development but also for tumour growth and other pathologies. It is promoted by different growth factors that stimulate endothelial cells to proliferate, migrate, and generate new tubular structures. Syndecans, transmembrane heparan sulphate proteoglycans, bind such growth factors through their glycosaminoglycan chains and could transduce the signal to the cytoskeleton, thus regulating cell behaviour. We demonstrated that syndecan-2, the major syndecan expressed by human microvascular endothelial cells, is regulated by growth factors and extracellular matrix proteins, in both bidimensional and tridimensional culture conditions. The role of syndecan-2 in 'in vitro' tumour angiogenesis was also examined by inhibiting its core protein expression with antisense phosphorothioate oligonucleotides. Downregulation of syndecan-2 reduces spreading and adhesion of endothelial cells, enhances their migration, but also impairs the formation of capillary-like structures. These results suggest that syndecan-2 has an important function in some of the necessary steps that make up the angiogenic process. We therefore propose a pivotal role of this heparan sulphate proteoglycan in the formation of new blood vessels.

  2. Solid tumor therapy by selectively targeting stromal endothelial cells.

    PubMed

    Liu, Shihui; Liu, Jie; Ma, Qian; Cao, Liu; Fattah, Rasem J; Yu, Zuxi; Bugge, Thomas H; Finkel, Toren; Leppla, Stephen H

    2016-07-12

    Engineered tumor-targeted anthrax lethal toxin proteins have been shown to strongly suppress growth of solid tumors in mice. These toxins work through the native toxin receptors tumor endothelium marker-8 and capillary morphogenesis protein-2 (CMG2), which, in other contexts, have been described as markers of tumor endothelium. We found that neither receptor is required for tumor growth. We further demonstrate that tumor cells, which are resistant to the toxin when grown in vitro, become highly sensitive when implanted in mice. Using a range of tissue-specific loss-of-function and gain-of-function genetic models, we determined that this in vivo toxin sensitivity requires CMG2 expression on host-derived tumor endothelial cells. Notably, engineered toxins were shown to suppress the proliferation of isolated tumor endothelial cells. Finally, we demonstrate that administering an immunosuppressive regimen allows animals to receive multiple toxin dosages and thereby produces a strong and durable antitumor effect. The ability to give repeated doses of toxins, coupled with the specific targeting of tumor endothelial cells, suggests that our strategy should be efficacious for a wide range of solid tumors. PMID:27357689

  3. Microwell arrays for uniform-sized embryoid body-mediated endothelial cell differentiation.

    PubMed

    Kim, Ji-eun; Lee, Jong Min; Chung, Bong Geun

    2014-08-01

    Embryonic stem (ES) cell is of great interest cell source in regenerating tissue constructs. We hypothesized that the interaction of cell-extracellular matrices (ECMs) would enable the control of ES cell differentiation pathway. We fabricated the hydrogel microwell array system to regulate uniform-sized embryoid bodies (EBs) and replate into various ECM components (e.g., gelatin, collagen I, fibronectin, laminin, and Matrigel). We demonstrated that collagen I and laminin largely induced ES cell-derived endothelial cell differentiation compared to gelatin. We also characterized ECMs-dependent endothelial cell differentiation by evaluating the endothelial gene expression, showing that Flk1 endothelial gene was highly expressed on collagen I. We also demonstrated the effect of the integrin on uniform-sized EBs-derived endothelial cell differentiation, showing that integrin α1 was largely expressed on laminin. Therefore, the cell-ECM interaction could be potentially powerful for controlling the uniform-sized EBs-derived endothelial cell differentiation. PMID:24652615

  4. Corneal endothelial cells possess an elaborate multipolar shape to maximize the basolateral to apical membrane area

    PubMed Central

    Harrison, Theresa A.; He, Zhiguo; Boggs, Kristin; Thuret, Gilles; Liu, Hong-Xiang

    2016-01-01

    Purpose The corneal endothelium is widely believed to consist of geometrically regular cells interconnected by junctional complexes. However, while en face visualization of the endothelial apical surface reveals characteristic polygonal borders, the overall form of the component cells has rarely been observed. Methods To visualize the shape of individual endothelial cells within the native monolayer, two independent Cre/LoxP-based cell labeling approaches were used. In the first, a P0-Cre mouse driver strain was bred to an R26-tdTomato reporter line to map neural crest–derived endothelial cells with cytosolic red fluorescent protein. In the second, HPRT-Cre induction of small numbers of green and red fluorescent protein–filled cells within a background of unlabeled cells was achieved using a dual-color reporter system, mosaic analysis with double markers (MADM). Selective imaging of the endothelial lateral membranes at different apicobasal levels was accomplished after staining with antibodies to ZO-1 and the neural cell adhesion molecule (NCAM). Results When viewed in their entirety in whole-mount preparations, fluorescent protein–filled cells appear star-shaped, extending multiple dendritic processes that radiate outward in the plane of the monolayer. Examination of rare cases where cells expressing different fluorescent proteins lie directly adjacent to one another reveals that these long processes undergo extensive interdigitation. The resulting overlap allows individual cells to extend over a greater area than if the cell boundaries were mutually exclusive. Anti-NCAM staining of these interlocking peripheral cell extensions reveals an elaborate system of lateral membrane folds that, when viewed in optical sections, increase in complexity from the apical to the basal pole. This not only produces a substantial increase in the basolateral, relative to the apical, membrane but also greatly extends the paracellular pathway as a highly convoluted space

  5. Primary tumor- and metastasis-derived colon cancer cells differently modulate connexin expression and function in human capillary endothelial cells.

    PubMed

    Thuringer, Dominique; Berthenet, Kevin; Cronier, Laurent; Solary, Eric; Garrido, Carmen

    2015-10-01

    A gradual loss of functional gap junction between tumor cells has been reported with colorectal cancer (CRC) progression. Here, we explored if colon cancer cells could also affect gap junctions in blood capillary cells. Human microvascular endothelial cells (HMEC) were cultured with two CRC cell lines established from a unique patient. SW480 cells, derived from the primary tumor, migrate much faster across HMEC monolayer than SW620 cells derived from a metastatic site. The motile SW480 cells highly express and release HSP27 that increases gap junction formation with HMEC. Soluble HSP27 phosphorylates the connexin Cx43 on serine residues and induces its interaction with the oncoprotein 14-3-3, which promotes Cx43 delivery at the plasma membrane. The factors secreted by less motile SW620 cells do not affect Cx43 expression but up-regulate the expression of the connexin Cx32 through an activation of the chemokine receptor CXCR2. In turn, SW620 secreted factors induce tubulogenesis and ATP release. Altogether, cell lines derived from CRC primary tumor and metastasis differentially adapt endothelial cell functions by modulating connexin expression through released mediators. PMID:26320187

  6. Endothelial lipase is localized to follicular epithelial cells in the thyroid gland and is moderately expressed in adipocytes.

    PubMed

    Connelly, Margery A; D'Andrea, Michael R; Qi, Jenson; Dzordzorme, Keli C; Damiano, Bruce P

    2012-09-01

    Endothelial lipase (EL), a member of the triglyceride lipase gene family, has been shown to be a key player in HDL metabolism. Northern blots revealed that EL was highly expressed in endothelium, thyroid, lung, placenta, liver, and testis. In liver and adrenal gland, EL protein was localized with vascular endothelial cells but not parenchymal cells. EL was shown to be upregulated in tissues such as atherosclerotic plaque where it was located in macrophages, endothelial cells, and medial smooth muscle cells. The purpose of this study was to investigate the cellular localization of EL in thyroid and other tissues where EL is known to be expressed. Besides its presence in vascular endothelial and smooth muscle cells, EL protein was detected in the epithelial cells that line the follicles within the thyroid gland. EL-specific immunostaining was also found near the cell surface as well as in the cytoplasm of adipocytes. Using immunoblots, EL expression was confirmed in cultured human omental and subcutaneous adipocytes. EL expression, however, was not found in preadipocytes. These findings suggest that EL plays a role in thyroid and adipocyte biology in addition to its well-known role in endothelial function and HDL metabolism. PMID:22740344

  7. Rat brain endothelial cells are a target of manganese toxicity

    PubMed Central

    Marreilha dos Santos, Ana Paula; Milatovic, Dejan; Au, Catherine; Yin, Zhaobao; Batoreu, Maria Camila C.; Aschner, Michael

    2010-01-01

    Manganese (Mn) is an essential trace metal, however exposure to high Mn levels can result in neurodegenerative changes resembling Parkinson´s disease (PD). Information on Mn´s effects on endothelial cells of the blood-brain barrier (BBB) is lacking. Accordingly, we tested the hypothesis that BBB endothelial cells are a primary target for Mn-induced neurotoxicity. The studies were conducted in an in vitro BBB model of immortalized rat brain endothelial (RBE4) cells. ROS production was determined by F2-Isoprostane (F2-IsoPs) measurement. The relationship between Mn toxicity and redox status was investigated upon intracellular glutathione (GSH) depletion with diethylmaleate (DEM) or L-buthionine sulfoximine (BSO). Mn exposure (200 or 800 µM MnCl2 or MnSO4) for 4 or 24h led to significant decrease in cell viability vs. controls. DEM or BSO pre-treatment led to further enhancement in cytotoxicity vs. exposure to Mn alone, with more pronounced cell death after 24h DEM pre-treatment. F2-IsoPs levels in cells exposed to MnCl2 (200 or 800 µM), were significantly increased after 4h and remained elevated 24h after exposure compared with controls. Consistent with the effects on cell viability and F2-IsoPs, treatment with MnCl2 (200 or 800 µM) was also associated with a significant decrease in membrane potential. This effect was more pronounced in cells exposed to DEM plus MnCl2 vs. cells exposed to Mn alone. We conclude that Mn induces direct injury to mitochondria in RBE4 cells. The ensuing impairment in energy metabolism and redox status may modify the restrictive properties of the BBB compromising its function. PMID:20170646

  8. Stem cell-derived vascular endothelial cells and their potential application in regenerative medicine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although a 'vascular stem cell' population has not been identified or generated, vascular endothelial and mural cells (smooth muscle cells and pericytes) can be derived from currently known pluripotent stem cell sources, including human embryonic stem cells and induced pluripotent stem cells. We rev...

  9. Gene silencing of endothelial von Willebrand Factor attenuates angiotensin II-induced endothelin-1 expression in porcine aortic endothelial cells.

    PubMed

    Dushpanova, Anar; Agostini, Silvia; Ciofini, Enrica; Cabiati, Manuela; Casieri, Valentina; Matteucci, Marco; Del Ry, Silvia; Clerico, Aldo; Berti, Sergio; Lionetti, Vincenzo

    2016-01-01

    Expression of endothelin (ET)-1 is increased in endothelial cells exposed to angiotensin II (Ang II), leading to endothelial dysfunction and cardiovascular disorders. Since von Willebrand Factor (vWF) blockade improves endothelial function in coronary patients, we hypothesized that targeting endothelial vWF with short interference RNA (siRNA) prevents Ang II-induced ET-1 upregulation. Nearly 65 ± 2% silencing of vWF in porcine aortic endothelial cells (PAOECs) was achieved with vWF-specific siRNA without affecting cell viability and growth. While showing ET-1 similar to wild type cells at rest, vWF-silenced cells did not present ET-1 upregulation during exposure to Ang II (100 nM/24 h), preserving levels of endothelial nitric oxide synthase activity similar to wild type. vWF silencing prevented AngII-induced increase in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activity and superoxide anion (O2-) levels, known triggers of ET-1 expression. Moreover, no increase in O2- or ET-1 levels was found in silenced cells treated with AngII or NOX-agonist phorbol ester (PMA 5 nM/48 h). Finally, vWF was required for overexpression of NOX4 and NOX2 in response to AngII and PMA. In conclusion, endothelial vWF knockdown prevented Ang II-induced ET-1 upregulation through attenuation of NOX-mediated O2- production. Our findings reveal a new role of vWF in preventing of Ang II-induced endothelial dysfunction. PMID:27443965

  10. Gene silencing of endothelial von Willebrand Factor attenuates angiotensin II-induced endothelin-1 expression in porcine aortic endothelial cells

    PubMed Central

    Dushpanova, Anar; Agostini, Silvia; Ciofini, Enrica; Cabiati, Manuela; Casieri, Valentina; Matteucci, Marco; Del Ry, Silvia; Clerico, Aldo; Berti, Sergio; Lionetti, Vincenzo

    2016-01-01

    Expression of endothelin (ET)-1 is increased in endothelial cells exposed to angiotensin II (Ang II), leading to endothelial dysfunction and cardiovascular disorders. Since von Willebrand Factor (vWF) blockade improves endothelial function in coronary patients, we hypothesized that targeting endothelial vWF with short interference RNA (siRNA) prevents Ang II-induced ET-1 upregulation. Nearly 65 ± 2% silencing of vWF in porcine aortic endothelial cells (PAOECs) was achieved with vWF-specific siRNA without affecting cell viability and growth. While showing ET-1 similar to wild type cells at rest, vWF-silenced cells did not present ET-1 upregulation during exposure to Ang II (100 nM/24 h), preserving levels of endothelial nitric oxide synthase activity similar to wild type. vWF silencing prevented AngII-induced increase in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activity and superoxide anion (O2−) levels, known triggers of ET-1 expression. Moreover, no increase in O2− or ET-1 levels was found in silenced cells treated with AngII or NOX-agonist phorbol ester (PMA 5 nM/48 h). Finally, vWF was required for overexpression of NOX4 and NOX2 in response to AngII and PMA. In conclusion, endothelial vWF knockdown prevented Ang II-induced ET-1 upregulation through attenuation of NOX-mediated O2− production. Our findings reveal a new role of vWF in preventing of Ang II-induced endothelial dysfunction. PMID:27443965

  11. Efficient nanoparticle mediated sustained RNA interference in human primary endothelial cells

    NASA Astrophysics Data System (ADS)

    Mukerjee, Anindita; Shankardas, Jwalitha; Ranjan, Amalendu P.; Vishwanatha, Jamboor K.

    2011-11-01

    Endothelium forms an important target for drug and/or gene therapy since endothelial cells play critical roles in angiogenesis and vascular functions and are associated with various pathophysiological conditions. RNA mediated gene silencing presents a new therapeutic approach to overcome many such diseases, but the major challenge of such an approach is to ensure minimal toxicity and effective transfection efficiency of short hairpin RNA (shRNA) to primary endothelial cells. In the present study, we formulated shAnnexin A2 loaded poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles which produced intracellular small interfering RNA (siRNA) against Annexin A2 and brought about the downregulation of Annexin A2. The per cent encapsulation of the plasmid within the nanoparticle was found to be 57.65%. We compared our nanoparticle based transfections with Lipofectamine mediated transfection, and our studies show that nanoparticle based transfection efficiency is very high (~97%) and is more sustained compared to conventional Lipofectamine mediated transfections in primary retinal microvascular endothelial cells and human cancer cell lines. Our findings also show that the shAnnexin A2 loaded PLGA nanoparticles had minimal toxicity with almost 95% of cells being viable 24 h post-transfection while Lipofectamine based transfections resulted in only 30% viable cells. Therefore, PLGA nanoparticle based transfection may be used for efficient siRNA transfection to human primary endothelial and cancer cells. This may serve as a potential adjuvant treatment option for diseases such as diabetic retinopathy, retinopathy of prematurity and age related macular degeneration besides various cancers.

  12. “Decoding” Angiogenesis: New Facets Controlling Endothelial Cell Behavior

    PubMed Central

    Sewduth, Raj; Santoro, Massimo M.

    2016-01-01

    Angiogenesis, the formation of new blood vessels, is a unique and crucial biological process occurring during both development and adulthood. A better understanding of the mechanisms that regulates such process is mandatory to intervene in pathophysiological conditions. Here we highlight some recent argument on new players that are critical in endothelial cells, by summarizing novel discoveries that regulate notorious vascular pathways such as Vascular Endothelial Growth Factor (VEGF), Notch and Planar Cell Polarity (PCP), and by discussing more recent findings that put metabolism, redox signaling and hemodynamic forces as novel unforeseen facets in angiogenesis. These new aspects, that critically regulate angiogenesis and vascular homeostasis in health and diseased, represent unforeseen new ground to develop anti-angiogenic therapies. PMID:27493632

  13. "Decoding" Angiogenesis: New Facets Controlling Endothelial Cell Behavior.

    PubMed

    Sewduth, Raj; Santoro, Massimo M

    2016-01-01

    Angiogenesis, the formation of new blood vessels, is a unique and crucial biological process occurring during both development and adulthood. A better understanding of the mechanisms that regulates such process is mandatory to intervene in pathophysiological conditions. Here we highlight some recent argument on new players that are critical in endothelial cells, by summarizing novel discoveries that regulate notorious vascular pathways such as Vascular Endothelial Growth Factor (VEGF), Notch and Planar Cell Polarity (PCP), and by discussing more recent findings that put metabolism, redox signaling and hemodynamic forces as novel unforeseen facets in angiogenesis. These new aspects, that critically regulate angiogenesis and vascular homeostasis in health and diseased, represent unforeseen new ground to develop anti-angiogenic therapies. PMID:27493632

  14. Inhibition of endothelial cell apoptosis by netrin-1 during angiogenesis.

    PubMed

    Castets, Marie; Coissieux, Marie-May; Delloye-Bourgeois, Céline; Bernard, Laure; Delcros, Jean-Guy; Bernet, Agnès; Laudet, Vincent; Mehlen, Patrick

    2009-04-01

    Netrin-1 was recently proposed to play an important role in embryonic and pathological angiogenesis. However, data reported led to the apparently contradictory conclusions that netrin-1 is either a pro- or an antiangiogenic factor. Here, we reconcile these opposing observations by demonstrating that netrin-1 acts as a survival factor for endothelial cells, blocking the proapoptotic effect of the dependence receptor UNC5B and its downstream death signaling effector, the serine/threonine kinase DAPK. The netrin-1 effect on blood vessel development is mimicked by caspase inhibitors in ex vivo assays, and the inhibition of caspase activity, the silencing of the UNC5B receptor, and the silencing of DAPK are each sufficient to rescue the vascular sprouting defects induced by netrin-1 silencing in zebrafish. Thus, the proapoptotic effect of unbound UNC5B and the survival effect of netrin-1 on endothelial cells finely tune the angiogenic process. PMID:19386270

  15. Endothelial progenitor cells accelerate the resolution of deep vein thrombosis.

    PubMed

    Li, Wen-Dong; Li, Xiao-Qiang

    2016-08-01

    Deep vein thrombosis (DVT) causes high morbidity and mortality. Successful resolution of DVT-related thrombi is the key point in the treatment of DVT. Recently, endothelial progenitor cells (EPCs) which are multipotent progenitor cells mainly residing in human bone marrow have emerged as a promising therapeutic choice for DVT-related thrombus resolution. In this review, we discussed the mobilization and homing property of EPCs into the sites of thrombosis, mechanisms of EPCs in DVT-related thrombus resolution from the aspects of promoting endothelial regeneration, revascularization, vasoactive and angiogenic factor secretion, proteinase generation, thrombus propagation and recurrence prevention, and vein wall remodeling. In addition, we also provide suggestions on EPCs as a therapeutic choice for thrombus resolution. PMID:26187355

  16. Vascular Endothelial Growth Factor A Regulates the Secretion of Different Angiogenic Factors in Lung Cancer Cells.

    PubMed

    Frezzetti, Daniela; Gallo, Marianna; Roma, Cristin; D'Alessio, Amelia; Maiello, Monica R; Bevilacqua, Simona; Normanno, Nicola; De Luca, Antonella

    2016-07-01

    Vascular endothelial growth factor A (VEGFA) is one of the main mediators of angiogenesis in non-small cell lung cancer (NSCLC). Recently, it has been described an autocrine feed-forward loop in NSCLC cells in which tumor-derived VEGFA promoted the secretion of VEGFA itself, amplifying the proangiogenic signal. In order to investigate the role of VEGFA in lung cancer progression, we assessed the effects of recombinant VEGFA on proliferation, migration, and secretion of other angiogenic factors in A549, H1975, and HCC827 NSCLC cell lines. We found that VEGFA did not affect NSCLC cell proliferation and migration. On the other hand, we demonstrated that VEGFA not only produced a strong and persistent increase of VEGFA itself but also significantly induced the secretion of a variety of angiogenic factors, including follistatin (FST), hepatocyte growth factor (HGF), angiopoietin-2 (ANGPT2), granulocyte-colony stimulating factor (G-CSF), interleukin (IL)-8, leptin (LEP), platelet/endothelial cell adhesion molecule 1 (PECAM-1), and platelet-derived growth factor bb (PDGF-BB). PI3K/AKT, RAS/ERK, and STAT3 signalling pathways were found to mediate the effects of VEGFA in NSCLC cell lines. We also observed that VEGFA regulation mainly occurred at post-transcriptional level and that NSCLC cells expressed different isoforms of VEGFA. Collectively, our data suggested that VEGFA contributes to lung cancer progression by inducing a network of angiogenic factors, which might offer potential for therapeutic intervention. PMID:26542886

  17. NOVEL CHARACTERIZATION OF bEnd.3 CELLS THAT EXPRESS LYMPHATIC VESSEL ENDOTHELIAL HYALURONAN RECEPTOR-1

    PubMed Central

    Yuen, D.; Leu, R.; Tse, J.; Wang, S.; Chen, L.L.; Chen, L.

    2015-01-01

    Murine bEnd.3 endothelioma cell line has been widely used in vascular research and here we report the novel finding that bEnd.3 cells express lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) and vascular endothelial growth factor receptor-3 (VEGFR-3). Moreover, these cells express progenitor cell markers of Sca-1 and CD133. Upon stimulation with tumor necrosis factor-alpha (TNF-α), the bEnd.3 cells demonstrate enhanced formation of capillary-type tubes, which express LYVE-1. As the bEnd.3 cell line is derived from murine endothelioma, we further examined human tissues of endothelioma and identified lymphatic vessels in the tumor samples which express both LYVE-1 and podoplanin. Moreover, a significantly higher number of lymphatic vessels were detected in the endothelioma samples compared with normal control. Taken together, this study not only redefines bEnd.3 cells for vascular research, but also indicates a broader category of human diseases that are associated with lymphatics, such as endothelioma. PMID:25282873

  18. Effect of Polyelectrolyte Film Stiffness on Endothelial Cells During Endothelial-to-Mesenchymal Transition.

    PubMed

    Zhang, He; Chang, Hao; Wang, Li-mei; Ren, Ke-feng; Martins, M Cristina L; Barbosa, Mário A; Ji, Jian

    2015-11-01

    Endothelial-to-mesenchymal transition (EndMT), during which endothelial cells (ECs) transdifferentiate into mesenchymal phenotype, plays a key role in the development of vascular implant complications such as endothelium dysfunction and in-stent restenosis. Substrate stiffness has been confirmed as a key factor to influence EC behaviors; however, so far, the relationship between substrate stiffness and EndMT has been rarely studied. Here, ECs were cultured on the (poly(L-lysine)/hyaluronate acid) (PLL/HA) multilayer films with controlled stiffness for 2 weeks, and their EndMT behaviors were studied. We demonstrated that ECs lost their markers (vWf and CD31) in a stiffness-dependent manner even without supplement of growth factors, and the softer film favored the maintaining of EC phenotype. Further, induced by transforming growth factor β1 (TGF-β1), ECs underwent EndMT, as characterized by losing their typical cobblestone morphology and markers and gaining smooth muscle cell markers (α-smooth muscle actin and calponin). Interestingly, stronger EndMT was observed when ECs were cultured on the stiffer film. Collectively, our findings suggest that substrate stiffness has significant effects on EndMT, and a softer substrate is beneficial to ECs by keeping their phenotype and inhibiting EndMT, which presents a new strategy for surface design of vascular implant materials. PMID:26477358

  19. Generation of vascular endothelial and smooth muscle cells from human pluripotent stem cells

    PubMed Central

    Patsch, Christoph; Challet-Meylan, Ludivine; Thoma, Eva C.; Urich, Eduard; Heckel, Tobias; O’Sullivan, John F; Grainger, Stephanie J; Kapp, Friedrich G.; Sun, Lin; Christensen, Klaus; Xia, Yulei; Florido, Mary H. C.; He, Wei; Pan, Wei; Prummer, Michael; Warren, Curtis R.; Jakob-Roetne, Roland; Certa, Ulrich; Jagasia, Ravi; Freskgård, Per-Ola; Adatto, Isaac; Kling, Dorothee; Huang, Paul; Zon, Leonard I; Chaikof, Elliot L.; Gerszten, Robert E.; Graf, Martin; Iacone, Roberto; Cowan, Chad A.

    2015-01-01

    The use of human pluripotent stem cells for in vitro disease modeling and clinical applications requires protocols that convert these cells into relevant adult cell types. Here, we report the rapid and efficient differentiation of human pluripotent stem cells into vascular endothelial and smooth muscle cells. We found that GSK3 inhibition and BMP4 treatment rapidly committed pluripotent cells to a mesodermal fate and subsequent exposure to VEGF or PDGF-BB resulted in the differentiation of either endothelial or vascular smooth muscle cells, respectively. Both protocols produced mature cells with efficiencies over 80% within six days. Upon purification to 99% via surface markers, endothelial cells maintained their identity, as assessed by marker gene expression, and showed relevant in vitro and in vivo functionality. Global transcriptional and metabolomic analyses confirmed that the cells closely resembled their in vivo counterparts. Our results suggest that these cells could be used to faithfully model human disease. PMID:26214132

  20. Generation of vascular endothelial and smooth muscle cells from human pluripotent stem cells.

    PubMed

    Patsch, Christoph; Challet-Meylan, Ludivine; Thoma, Eva C; Urich, Eduard; Heckel, Tobias; O'Sullivan, John F; Grainger, Stephanie J; Kapp, Friedrich G; Sun, Lin; Christensen, Klaus; Xia, Yulei; Florido, Mary H C; He, Wei; Pan, Wei; Prummer, Michael; Warren, C