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Sample records for affect endothelial cell

  1. 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.

  2. 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

  3. 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

  4. Bioglass promotes wound healing by affecting gap junction connexin 43 mediated endothelial cell behavior.

    PubMed

    Li, Haiyan; He, Jin; Yu, Hongfei; Green, Colin R; Chang, Jiang

    2016-04-01

    It is well known that gap junctions play an important role in wound healing, and bioactive glass (BG) has been shown to help healing when applied as a wound dressing. However, the effects of BG on gap junctional communication between cells involved in wound healing is not well understood. We hypothesized that BG may be able to affect gap junction mediated cell behavior to enhance wound healing. Therefore, we set out to investigate the effects of BG on gap junction related behavior of endothelial cells in order to elucidate the mechanisms through which BG is operating. In in vitro studies, BG ion extracts prevented death of human umbilical vein endothelial cells (HUVEC) following hypoxia in a dose dependent manner, possibly through connexin hemichannel modulation. In addition, BG showed stimulatory effects on gap junction communication between HUVECs and upregulated connexin43 (Cx43) expression. Furthermore, BG prompted expression of vascular endothelial growth factor and basic fibroblast growth factor as well as their receptors, and vascular endothelial cadherin in HUVECs, all of which are beneficial for vascularization. In vivo wound healing results showed that the wound closure of full-thickness excisional wounds of rats was accelerated by BG with reduced inflammation during initial stages of healing and stimulated angiogenesis during the proliferation stage. Therefore, BG can stimulate wound healing through affecting gap junctions and gap junction related endothelial cell behaviors, including prevention of endothelial cell death following hypoxia, stimulation of gap junction communication and upregulation of critical vascular growth factors, which contributes to the enhancement of angiogenesis in the wound bed and finally to accelerate wound healing. Although many studies have reported that BG stimulates angiogenesis and wound healing, this work reveals the relationship between BG and gap junction connexin 43 mediated endothelial cell behavior and elucidates

  5. 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.

  6. Hyaluronic acid hydrogel stiffness and oxygen tension affect cancer cell fate and endothelial sprouting

    PubMed Central

    Shen, Yu-I; Abaci, Hasan E.; Krupsi, Yoni; Weng, Lien-Chun; Burdick, Jason A.; Gerecht, Sharon

    2014-01-01

    Three-dimensional (3D) tissue culture models may recapitulate aspects of the tumorigenic microenvironment in vivo, enabling the study of cancer progression in vitro. Both hypoxia and matrix stiffness are known to regulate tumor growth. Using a modular culture system employing an acrylated hyaluronic acid (AHA) hydrogel, three hydrogel matrices with distinctive degrees of viscoelasticity — soft (78±16 Pa), medium (309± 57 Pa), and stiff (596± 73 Pa) — were generated using the same concentration of adhesion ligands. Oxygen levels within the hydrogel in atmospheric (21 %), hypoxic (5 %), and severely hypoxic (1 %) conditions were assessed with a mathematical model. HT1080 fibrosarcoma cells, encapsulated within the AHA hydrogels in high densities, generated nonuniform oxygen distributions, while lower cell densities resulted in more uniform oxygen distributions in the atmospheric and hypoxic environments. When we examined how varying viscoelasticity in atmospheric and hypoxic environments affects cell cycles and the expression of BNIP3 and BNIP3L (autophagy and apoptosis genes), and GLUT-1 (a glucose transport gene), we observed that HT1080 cells in 3D hydrogel adapted better to hypoxic conditions than those in a Petri dish, with no obvious correlation to matrix viscoelasticity, by recovering rapidly from possible autophagy/apoptotic events and alternating metabolism mechanisms. Further, we examined how HT1080 cells cultured in varying viscoelasticity and oxygen tension conditions affected endothelial sprouting and invasion. We observed that increased matrix stiffness reduced endothelial sprouting and invasion in atmospheric conditions; however, we observed increased endothelial sprouting and invasion under hypoxia at all levels of matrix stiffness with the upregulation of vascular endothelial growth factor (VEGF) and angiopoeitin-1 (ANG-1). Overall, HT1080 cells encapsulated in the AHA hydrogels under hypoxic stress recovered better from apoptosis and

  7. Cyclic Stretch Affects Pulmonary Endothelial Cell Control of Pulmonary Smooth Muscle Cell Growth

    PubMed Central

    Ochoa, Cristhiaan D.; Baker, Haven; Hasak, Stephen; Matyal, Robina; Salam, Aleya; Hales, Charles A.; Hancock, William; Quinn, Deborah A.

    2008-01-01

    Endothelial cells are subjected to mechanical forces in the form of cyclic stretch resulting from blood pulsatility. Pulmonary artery endothelial cells (PAECs) produce factors that stimulate and inhibit pulmonary artery smooth muscle cell (PASMC) growth. We hypothesized that PAECs exposed to cyclic stretch secrete proteins that inhibit PASMC growth. Media from PAECs exposed to cyclic stretch significantly inhibited PASMC growth in a time-dependent manner. Lyophilized material isolated from stretched PAEC-conditioned media significantly inhibited PASMC growth in a dose-dependent manner. This inhibition was reversed by trypsin inactivation, which is consistent with the relevant factor being a protein(s). To identify proteins that inhibited cell growth in conditioned media from stretched PAECs, we used proteomic techniques and found that thrombospondin (TSP)-1, a natural antiangiogenic factor, was up-regulated by stretch. In vitro, exogenous TSP-1 inhibited PASMC growth. TSP-1–blocking antibodies reversed conditioned media–induced inhibition of PASMC growth. Cyclic stretched PAECs secrete protein(s) that inhibit PASMC proliferation. TSP-1 may be, at least in part, responsible for this inhibition. The complete identification and understanding of the secreted proteome of stretched PAECs may lead to new insights into the pathophysiology of pulmonary vascular remodeling. PMID:18314539

  8. Polyphenolic composition of grape stem extracts affects antioxidant activity in endothelial and muscle cells.

    PubMed

    Goutzourelas, Nikolaos; Stagos, Dimitrios; Spanidis, Ypatios; Liosi, Maria; Apostolou, Anna; Priftis, Alexandros; Haroutounian, Serko; Spandidos, Demetrios A; Tsatsakis, Aristidis M; Kouretas, Demetrios

    2015-10-01

    The aim of the present study was the assessment of the antioxidant effects of polyphenolic extracts derived from the stems of three Greek grape varieties (Moshomayro, Mavrotragano and Mandilaria) in endothelial (EA.hy926) and muscle (C2C12) cells. We also investigated the effects of the polyphenolic composition on the antioxidant effects of the grape stem extracts. For this purpose, the endothelial and muscle cells were treated with low non-cytotoxic concentrations of the extracts for 24 h in order to assess the effects of the extracts on cellular redox status using oxidative stress biomarkers. The oxidative stress markers were thiobarbituric acid reactive substances (TBARS), protein carbonyl (CARB) levels, reactive oxygen species (ROS) levels and glutathione (GSH) levels. The results revealed that treatment of the EA.hy926 cells with Mandilaria extract significantly decreased the TBARS levels by 14.8% and the CARB levels by 25.9 %, while it increased the GSH levels by 15.8% compared to the controls. Moreover, treatment of the EA.hy926 cells with Mavrotragano extract significantly increased the GSH levels by 20.2%, while it significantly decreased the TBARS and CARB levels by 12.5% and 16.6%, respectively. Treatment of the C2C12 cells with Mandilaria extract significantly decreased the TBARS levels by 47.3 %, the CARB levels by 39.0 % and the ROS levels by 21.8%, while it increased the GSH levels by 22.6% compared to the controls. Moreover, treatment of the C2C12 cells with Mavrotragano significantly decreased the TBARS, CARB and ROS levels by 36.2%, 35.9% and 16.5%, respectively. In conclusion, to the best of our knowledgel, our results demonstrate for the first time that treatment with grape stem extracts at low concentrations improves the redox status of endothelial and muscle cells. Thus, grape stem extracts may be used for developing antioxidant food supplements or biofunctional foods. However, it was also found that the polyphenolic composition of grape stem

  9. Polyphenolic composition of grape stem extracts affects antioxidant activity in endothelial and muscle cells

    PubMed Central

    GOUTZOURELAS, NIKOLAOS; STAGOS, DIMITRIOS; SPANIDIS, YPATIOS; LIOSI, MARIA; APOSTOLOU, ANNA; PRIFTIS, ALEXANDROS; HAROUTOUNIAN, SERKO; SPANDIDOS, DEMETRIOS A.; TSATSAKIS, ARISTIDIS M.; KOURETAS, DEMETRIOS

    2015-01-01

    The aim of the present study was the assessment of the antioxidant effects of polyphenolic extracts derived from the stems of three Greek grape varieties (Moshomayro, Mavrotragano and Mandilaria) in endothelial (EA.hy926) and muscle (C2C12) cells. We also investigated the effects of the polyphenolic composition on the antioxidant effects of the grape stem extracts. For this purpose, the endothelial and muscle cells were treated with low non-cytotoxic concentrations of the extracts for 24 h in order to assess the effects of the extracts on cellular redox status using oxidative stress biomarkers. The oxidative stress markers were thiobarbituric acid reactive substances (TBARS), protein carbonyl (CARB) levels, reactive oxygen species (ROS) levels and glutathione (GSH) levels. The results revealed that treatment of the EA.hy926 cells with Mandilaria extract significantly decreased the TBARS levels by 14.8% and the CARB levels by 25.9 %, while it increased the GSH levels by 15.8% compared to the controls. Moreover, treatment of the EA.hy926 cells with Mavrotragano extract significantly increased the GSH levels by 20.2%, while it significantly decreased the TBARS and CARB levels by 12.5% and 16.6%, respectively. Treatment of the C2C12 cells with Mandilaria extract significantly decreased the TBARS levels by 47.3 %, the CARB levels by 39.0 % and the ROS levels by 21.8%, while it increased the GSH levels by 22.6% compared to the controls. Moreover, treatment of the C2C12 cells with Mavrotragano significantly decreased the TBARS, CARB and ROS levels by 36.2%, 35.9% and 16.5%, respectively. In conclusion, to the best of our knowledgel, our results demonstrate for the first time that treatment with grape stem extracts at low concentrations improves the redox status of endothelial and muscle cells. Thus, grape stem extracts may be used for developing antioxidant food supplements or biofunctional foods. However, it was also found that the polyphenolic composition of grape stem

  10. Change in properties of the glycocalyx affects the shear rate and stress distribution on endothelial cells.

    PubMed

    Wang, Wen

    2007-06-01

    The endothelial glycocalyx mediates interactions between the blood flow and the endothelium. This study aims to evaluate, quantitatively, effects of structural change of the glycocalyx on stress distribution and shear rate on endothelial cells. In the study, the endothelial glycocalyx is modeled as a surface layer of fiber matrix and when exposed to laminar shear flow, the matrix deforms. Fluid velocity and stress distribution inside the matrix and on cell membranes are studied based on a binary mixture theory. Parameters, such as the height and porosity of the matrix and the drag coefficient between fluid and matrix fibrils, are based on available data and estimation from experiments. Simple theoretical solutions are achieved for fluid velocity and stress distribution in the surface matrix. Degradation of the matrix, e.g., by enzyme digestion, is represented by reductions in the volume fraction of fibrils, height, and drag coefficient. From a force balance, total stress on endothelial surface remains constant regardless of structural alteration of the glycocalyx. However, the stress that is transmitted to endothelial cells by direct "pulling" of fiber branches of the glycocalyx is reduced significantly. Fluid shear rate at the cell membrane, on the other hand, increases. The study gives quantitative insight into the effect of the structural change of the glycocalyx on the shear rate and pulling stress on the endothelium. Results can be used to interpret experiments on effects of the glycocalyx in shear induced endothelial responses. PMID:17536899

  11. The Presence of VEGF Receptors on the Luminal Surface of Endothelial Cells Affects VEGF Distribution and VEGF Signaling

    PubMed Central

    Stefanini, Marianne O.; Wu, Florence T. H.; Mac Gabhann, Feilim; Popel, Aleksander S.

    2009-01-01

    Vascular endothelial growth factor (VEGF) is a potent cytokine that binds to specific receptors on the endothelial cells lining blood vessels. The signaling cascade triggered eventually leads to the formation of new capillaries, a process called angiogenesis. Distributions of VEGF receptors and VEGF ligands are therefore crucial determinants of angiogenic events and, to our knowledge, no quantification of abluminal vs. luminal receptors has been performed. We formulate a molecular-based compartment model to investigate the VEGF distribution in blood and tissue in humans and show that such quantification would lead to new insights on angiogenesis and VEGF-dependent diseases. Our multiscale model includes two major isoforms of VEGF (VEGF121 and VEGF165), as well as their receptors (VEGFR1 and VEGFR2) and the non-signaling co-receptor neuropilin-1 (NRP1). VEGF can be transported between tissue and blood via transendothelial permeability and the lymphatics. VEGF receptors are located on both the luminal and abluminal sides of the endothelial cells. In this study, we analyze the effects of the VEGF receptor localization on the endothelial cells as well as of the lymphatic transport. We show that the VEGF distribution is affected by the luminal receptor density. We predict that the receptor signaling occurs mostly on the abluminal endothelial surface, assuming that VEGF is secreted by parenchymal cells. However, for a low abluminal but high luminal receptor density, VEGF binds predominantly to VEGFR1 on the abluminal surface and VEGFR2 on the luminal surface. Such findings would be pertinent to pathological conditions and therapies related to VEGF receptor imbalance and overexpression on the endothelial cells and will hopefully encourage experimental receptor quantification for both luminal and abluminal surfaces on endothelial cells. PMID:20041209

  12. Extracellular S100A4 affects endothelial cell integrity and stimulates transmigration of A375 melanoma cells.

    PubMed

    Herwig, Nadine; Belter, Birgit; Pietzsch, Jens

    2016-09-01

    High extracellular S100A4 level proves a specific characteristic of some cancer cases, including malignant melanoma. Concerning the latter, extracellular S100A4 in an autocrine manner was shown to promote prometastatic activation of A375 cells by interaction with the receptor for advanced glycation endproducts (RAGE). We hypothesized that interaction of extracellular S100A4 with RAGE in a paracrine manner will affect endothelial cell (EC) integrity thus further promoting melanoma metastasis. We investigated the influence of recombinant and cell (A375)-derived S100A4 on junction protein expression and EC (hCMEC/D3) integrity by measuring transendothelial electrical resistance (TEER). Decrease of TEER and diminished expression of both occludin and VE-cadherin revealed the loss of EC integrity. Transmigration of transgenic A375 cells (A375-hS100A4/A375-hRAGE) through the EC monolayer was significantly higher compared to wild-type A375 cells, and was substantially decreased by sRAGE. A pilot study in mice, intracardially injected with A375-hS100A4 or A375-hRAGE cells, showed lower survival rates and a higher incidence of metastases compared to wild-type A375 cells. Tumor development was mostly located in the brain, bones, and ovaries. These findings provide further evidence on extracellular S100A4 as paracrine mediator of prometastatic endothelial dysfunction involving its interaction with RAGE. PMID:27387233

  13. Atherosclerosis differentially affects calcium signalling in endothelial cells from aortic arch and thoracic aorta in Apolipoprotein E knockout mice

    PubMed Central

    Prendergast, Clodagh; Quayle, John; Burdyga, Theodor; Wray, Susan

    2014-01-01

    Abstract Apolipoprotein‐E knockout (ApoE−/−) mice develop hypercholesterolemia and are a useful model of atherosclerosis. Hypercholesterolemia alters intracellular Ca2+ signalling in vascular endothelial cells but our understanding of these changes, especially in the early stages of the disease process, is limited. We therefore determined whether carbachol‐mediated endothelial Ca2+ signals differ in plaque‐prone aortic arch compared to plaque‐resistant thoracic aorta, of wild‐type and ApoE−/− mice, and how this is affected by age and the presence of hypercholesterolemia. The extent of plaque development was determined using en‐face staining with Sudan IV. Tissues were obtained from wild‐type and ApoE−/− mice at 10 weeks (pre‐plaques) and 24 weeks (established plaques). We found that even before development of plaques, significantly increased Ca2+ responses were observed in arch endothelial cells. Even with aging and plaque formation, ApoE−/− thoracic responses were little changed, however a significantly enhanced Ca2+ response was observed in arch, both adjacent to and away from lesions. In wild‐type mice of any age, 1–2% of cells had oscillatory Ca2+ responses. In young ApoE−/− and plaque‐free regions of older ApoE−/−, this is unchanged. However a significant increase in oscillations (~13–15%) occurred in thoracic and arch cells adjacent to lesions in older mice. Our data suggest that Ca2+ signals in endothelial cells show specific changes both before and with plaque formation, that these changes are greatest in plaque‐prone aortic arch cells, and that these changes will contribute to the reported deterioration of endothelium in atherosclerosis. PMID:25344475

  14. Thyroid hormone affects both endothelial and vascular smooth muscle cells in rat arteries.

    PubMed

    Cai, Yin; Manio, Michael M; Leung, George P H; Xu, Aimin; Tang, Eva H C; Vanhoutte, Paul M

    2015-01-15

    Hypothyroidism impairs endothelium-dependent dilatations, while hyperthyroidism augments the production of endothelial nitric oxide. Thus, experiments were designed to determine if thyroid hormone causes endothelium-dependent responses, or alleviates diabetic endothelial dysfunction. Isometric tension was measured in rings with or without endothelium of arteries from normal and diabetic Sprague-Dawley rats. Release of 6-keto prostaglandin F1α and thromboxane B2 were measured by enzyme linked immunosorbent assay and protein levels [endothelial nitric oxide synthase (eNOS), cyclooxygenases (COX)] by immunoblotting. Triiodothyronine (T3) caused concentration-dependent (3×10(-6)-3×10(-5)M) relaxations in mesenteric (pEC50, 4.96±0.19) and femoral (pEC50, 4.57±0.35) arteries without endothelium. In femoral arteries of rats with diabetes, 5-methylamino-2-[[(2S,3R,5R,8S,9S)-3,5,9-trimethyl-2-(1-oxo-(1H-pyrrol-2- -yl)propan-2-yl)-1,7-dioxaspiro-(5,5)undecan-8-yl]methyl]benzooxazole-4-carboxylic acid (A23187, 3×10(-7) to 10(-6)M) caused partly endothelium-dependent contractions. After chronic T3-treatment with (10μg/kg/day; four weeks), the contractions to A23187 of preparations with and without endothelium were comparable, the thromboxane B2-release was reduced (by 38.1±9.2%). The pEC50 of 9, 11-dideoxy-11α, 9α-epoxymethanoprostaglandin F2α (U46619, TP-receptor agonist) was increased in T3-treated diabetic rats compared with controls (8.53±0.06 vs 7.94±0.09). The protein expression of eNOS increased (by 228%) but that of COX-1 decreased (by 35%) after chronic T3 treatment. In human umbilical vein endothelial cells incubated for one week with T3 (10(-10)-10(-7)M) in the presence but not in the absence of interleukin-1β (1ng/ml), the expression of eNOS was increased compared to control. In conclusion, thyroid hormone acutely relaxes mesenteric and femoral vascular smooth muscle, but given chronically reduces the release of endothelium-derived vasoconstrictor

  15. 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

  16. Hyperglycemia Does Not Affect Iron Mediated Toxicity of Cultured Endothelial and Renal Tubular Epithelial Cells: Influence of L-Carnosine

    PubMed Central

    Zhang, Shiqi; Ntasis, Emmanouil; Kabtni, Sarah; van den Born, Jaap; Navis, Gerjan; Bakker, Stephan J. L.; Krämer, Bernhard K.; Yard, Benito A.; Hauske, Sibylle J.

    2016-01-01

    Iron has been suggested to affect the clinical course of type 2 diabetes (T2DM) as accompanying increased intracellular iron accumulation may provide an alternative source for reactive oxygen species (ROS). Although carnosine has proven its therapeutic efficacy in rodent models of T2DM, little is known about its efficacy to protect cells from iron toxicity. We sought to assess if high glucose (HG) exposure makes cultured human umbilical vein endothelial cells (HUVECs) and renal proximal tubular epithelial cells (PTECs) more susceptible to metal induced toxicity and if this is ameliorated by L-carnosine. HUVECs and PTECs, cultured under normal glucose (5 mM, NG) or HG (30 mM), were challenged for 24 h with FeCl3. Cell viability was not impaired under HG conditions nor did HG increase susceptibility to FeCl3. HG did not change the expression of divalent metal transporter 1 (DMT1), ferroportin (IREG), and transferrin receptor protein 1 (TFRC). Irrespective of glucose concentrations L-carnosine prevented toxicity in a dose-dependent manner, only if it was present during the FeCl3 challenge. Hence our study indicates that iron induced cytotoxicity is not enhanced under HG conditions. L-Carnosine displayed a strong protective effect, most likely by chelation of iron mediated toxicity. PMID:26788523

  17. Hyperglycemia Does Not Affect Iron Mediated Toxicity of Cultured Endothelial and Renal Tubular Epithelial Cells: Influence of L-Carnosine.

    PubMed

    Zhang, Shiqi; Ntasis, Emmanouil; Kabtni, Sarah; van den Born, Jaap; Navis, Gerjan; Bakker, Stephan J L; Krämer, Bernhard K; Yard, Benito A; Hauske, Sibylle J

    2016-01-01

    Iron has been suggested to affect the clinical course of type 2 diabetes (T2DM) as accompanying increased intracellular iron accumulation may provide an alternative source for reactive oxygen species (ROS). Although carnosine has proven its therapeutic efficacy in rodent models of T2DM, little is known about its efficacy to protect cells from iron toxicity. We sought to assess if high glucose (HG) exposure makes cultured human umbilical vein endothelial cells (HUVECs) and renal proximal tubular epithelial cells (PTECs) more susceptible to metal induced toxicity and if this is ameliorated by L-carnosine. HUVECs and PTECs, cultured under normal glucose (5 mM, NG) or HG (30 mM), were challenged for 24 h with FeCl3. Cell viability was not impaired under HG conditions nor did HG increase susceptibility to FeCl3. HG did not change the expression of divalent metal transporter 1 (DMT1), ferroportin (IREG), and transferrin receptor protein 1 (TFRC). Irrespective of glucose concentrations L-carnosine prevented toxicity in a dose-dependent manner, only if it was present during the FeCl3 challenge. Hence our study indicates that iron induced cytotoxicity is not enhanced under HG conditions. L-Carnosine displayed a strong protective effect, most likely by chelation of iron mediated toxicity. PMID:26788523

  18. Serum From Advanced Heart Failure Patients Promotes Angiogenic Sprouting and Affects the Notch Pathway in Human Endothelial Cells.

    PubMed

    Pannella, Micaela; Caliceti, Cristiana; Fortini, Francesca; Aquila, Giorgio; Vieceli Dalla Sega, Francesco; Pannuti, Antonio; Fortini, Cinzia; Morelli, Marco Bruno; Fucili, Alessandro; Francolini, Gloria; Voltan, Rebecca; Secchiero, Paola; Dinelli, Giovanni; Leoncini, Emanuela; Ferracin, Manuela; Hrelia, Silvana; Miele, Lucio; Rizzo, Paola

    2016-12-01

    It is unknown whether components present in heart failure (HF) patients' serum provide an angiogenic stimulus. We sought to determine whether serum from HF patients affects angiogenesis and its major modulator, the Notch pathway, in human umbilical vein endothelial cells (HUVECs). In cells treated with serum from healthy subjects or from patients at different HF stage we determined: (1) Sprouting angiogenesis, by measuring cells network (closed tubes) in collagen gel. (2) Protein levels of Notch receptors 1, 2, 4, and ligands Jagged1, Delta-like4. We found a higher number of closed tubes in HUVECs treated with advanced HF patients serum in comparison with cells treated with serum from mild HF patients or controls. Furthermore, as indicated by the reduction of the active form of Notch4 (N4IC) and of Jagged1, advanced HF patients serum inhibited Notch signalling in HUVECs in comparison with mild HF patients' serum and controls. The circulating levels of NT-proBNP (N-terminal of the pro-hormone brain natriuretic peptide), a marker for the detection and evalutation of HF, were positively correlated with the number of closed tubes (r = 0.485) and negatively with Notch4IC and Jagged1 levels in sera-treated cells (r = -0.526 and r = -0.604, respectively). In conclusion, we found that sera from advanced HF patients promote sprouting angiogenesis and dysregulate Notch signaling in HUVECs. Our study provides in vitro evidence of an angiogenic stimulus arising during HF progression and suggests a role for the Notch pathway in it. J. Cell. Physiol. 231: 2700-2710, 2016. © 2016 Wiley Periodicals, Inc. PMID:26987674

  19. How mental stress affects endothelial function.

    PubMed

    Toda, Noboru; Nakanishi-Toda, Megumi

    2011-12-01

    Mental stress is an important factor contributing to recognized mechanisms underlying cardiovascular events. Among these, stress-related endothelial dysfunction is an early risk factor that predicts future development of severe cardiovascular disorders. Acute mental stress by a variety of tests impairs endothelial function in humans, although the opposite results have been reported by some investigators. Chronic stress always deteriorates endothelial function in humans and experimental animals. Stress hormones, such as glucocorticoids and pro-inflammatory cytokines, and endothelin-1 liberated in response to mental stress participate in endothelial dysfunction possibly via downregulation of endothelial nitric oxide synthase (eNOS) expression, eNOS inactivation, decreased nitric oxide (NO) actions, and increased NO degradation, together with vasoconstriction counteracting against NO-induced vasodilatation. Catecholamines do not directly affect endothelial function but impair its function when blood pressure elevation by the amines is sustained. Endogenous opioids favorably affect endothelial function, which counteract deteriorating effects of other stress hormones and mediators. Inhibition of cortisol and endothelin-1 production, prevention of pro-inflammatory mediator accumulation, hypnotics, mirthful laughter, humor orientation, and lifestyle modification would contribute to the prevention and treatment for stress-related endothelial dysfunction and future serious cardiovascular disease. PMID:21947555

  20. p-Cresol Affects Reactive Oxygen Species Generation, Cell Cycle Arrest, Cytotoxicity and Inflammation/Atherosclerosis-Related Modulators Production in Endothelial Cells and Mononuclear Cells

    PubMed Central

    Chan, Chiu-Po; Yeung, Sin-Yuet; Hsien, Hsiang-Chi; Lin, Bor-Ru; Yeh, Chien-Yang; Tseng, Wan-Yu; Tseng, Shui-Kuan; Jeng, Jiiang-Huei

    2014-01-01

    Aims Cresols are present in antiseptics, coal tar, some resins, pesticides, and industrial solvents. Cresol intoxication leads to hepatic injury due to coagulopathy as well as disturbance of hepatic circulation in fatal cases. Patients with uremia suffer from cardiovascular complications, such as atherosclerosis, thrombosis, hemolysis, and bleeding, which may be partly due to p-cresol toxicity and its effects on vascular endothelial and mononuclear cells. Given the role of reactive oxygen species (ROS) and inflammation in vascular thrombosis, the objective of this study was to evaluate the effect of p-cresol on endothelial and mononuclear cells. Methods EA.hy926 (EAHY) endothelial cells and U937 cells were exposed to different concentrations of p-cresol. Cytotoxicity was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5 -diphenyltetrazolium bromide (MTT) assay and trypan blue dye exclusion technique, respectively. Cell cycle distribution was analyzed by propidium iodide flow cytometry. Endothelial cell migration was studied by wound closure assay. ROS level was measured by 2′,7′-dichlorofluorescein diacetate (DCF) fluorescence flow cytometry. Prostaglandin F2α (PGF2α), plasminogen activator inhibitor-1 (PAI-1), soluble urokinase plasminogen activator receptor (suPAR), and uPA production were determined by Enzyme-linked immunosorbant assay (ELISA). Results Exposure to 100–500 µM p-cresol decreased EAHY cell number by 30–61%. P-cresol also decreased the viability of U937 mononuclear cells. The inhibition of EAHY and U937 cell growth by p-cresol was related to induction of S-phase cell cycle arrest. Closure of endothelial wounds was inhibited by p-cresol (>100 µM). P-cresol (>50 µM) also stimulated ROS production in U937 cells and EAHY cells but to a lesser extent. Moreover, p-cresol markedly stimulated PAI-1 and suPAR, but not PGF2α, and uPA production in EAHY cells. Conclusions p-Cresol may contribute to atherosclerosis and thrombosis in patients with

  1. The challenging environment on board the International Space Station affects endothelial cell function by triggering oxidative stress through thioredoxin interacting protein overexpression: the ESA-SPHINX experiment.

    PubMed

    Versari, Silvia; Longinotti, Giulia; Barenghi, Livia; Maier, Jeanette Anne Marie; Bradamante, Silvia

    2013-11-01

    Exposure to microgravity generates alterations that are similar to those involved in age-related diseases, such as cardiovascular deconditioning, bone loss, muscle atrophy, and immune response impairment. Endothelial dysfunction is the common denominator. To shed light on the underlying mechanism, we participated in the Progress 40P mission with Spaceflight of Human Umbilical Vein Endothelial Cells (HUVECs): an Integrated Experiment (SPHINX), which consisted of 12 in-flight and 12 ground-based control modules and lasted 10 d. Postflight microarray analysis revealed 1023 significantly modulated genes, the majority of which are involved in cell adhesion, oxidative phosphorylation, stress responses, cell cycle, and apoptosis. Thioredoxin-interacting protein was the most up-regulated (33-fold), heat-shock proteins 70 and 90 the most down-regulated (5.6-fold). Ion channels (TPCN1, KCNG2, KCNJ14, KCNG1, KCNT1, TRPM1, CLCN4, CLCA2), mitochondrial oxidative phosphorylation, and focal adhesion were widely affected. Cytokine detection in the culture media indicated significant increased secretion of interleukin-1α and interleukin-1β. Nitric oxide was found not modulated. Our data suggest that in cultured HUVECs, microgravity affects the same molecular machinery responsible for sensing alterations of flow and generates a prooxidative environment that activates inflammatory responses, alters endothelial behavior, and promotes senescence. PMID:23913861

  2. Chinese herbal medicinal ingredients affect secretion of NO, IL-10, ICAM-1 and IL-2 by endothelial cells.

    PubMed

    Hu, Yiyi; He, Kongwang; Zhu, Haodan

    2015-06-01

    The aim of this study was to investigate the anti-endotoxin effects of sinomenine, fangchinoline, stachydrine, chuanxionggzine, oxymartrine and evodiamine alkaloids commonly found in Chinese herbal medicines. Porcine endothelial cells were challenged with 1 μg LPS/ml for 3 h and then treated with one of the six alkaloids at three concentrations (1, 5 or 10 μg/ml) for a further 21 h. The supernatants of the cultures were then collected and analyzed for levels of nitric oxide (NO), interleukin (IL)-10, intercellular cell adhesion molecule-1 (ICAM-1) and IL-2 using ELISA kits. The results revealed that sinomenine, stachydrine and chuanxionggzine inhibited production of NO; stachydrine and evodiamine inhibited secretion of IL-10; sinomenine and chuanxionggzine down-regulated ICAM-1 expression; oxymartrine and evodiamine decreased production of IL-2 by the LPS-stimulated endothelial cells. Overall, the data from these studies suggested to us that these six alkaloids might effectively reduce inflammatory responses in situ via changes in the formation of these key regulatory molecules/proteins. PMID:25986990

  3. Lactate adversely affects the in vitro formation of endothelial cell tubular structures through the action of TGF-{beta}1

    SciTech Connect

    Schmid, Stephan A. . E-mail: leoni.kunz-schughart@oncoray.de; Gaumann, Andreas; Wondrak, Marit; Eckermann, Christoph; Schulte, Stephanie; Mueller-Klieser, Wolfgang; Wheatley, Denys N.; Kunz-Schughart, Leoni A.

    2007-07-15

    When lactate accumulation in a tumor microenvironment reaches an average concentration of 10-20 mM, it tends to reflect a high degree of malignancy. However, the hypothesis that tumor-derived lactate has a number of partially adverse biological effects on malignant and tumor-associated host cells requires further evidence. The present study attempted to evaluate the impact of lactate on the process of angiogenesis, in particular on the formation of tubular structures. The endothelial cell (EC) network in desmoplastic breast tumors is primarily located in areas of reactive fibroblastic stroma. We employed a fibroblast-endothelial cell co-culture model as in vitro angiogenesis system normally producing florid in vitro tubule formation to analyze this situation. In contrast to previous studies, we found that lactate significantly reduces EC network formation in a dose-dependent manner as quantified by semi-automated morphometric analyses following immunohistochemical staining. The decrease in CD31-positive tubular structures and the number of intersections was independent of VEGF supplementation and became more pronounced in the presence of protons. The number of cells, primarily of the fibroblast population, was reduced but cell loss could not be attributed to a decrease in proliferative activity or pronounced apoptotic cell death. Treatment with 10 mM lactate was accompanied by enhanced mRNA expression and release of TGF-{beta}1, which also shows anti-angiogenic activity in the model. Both TGF-{beta}1 and lactate induced myofibroblastic differentiation adjacent to the EC tubular structures. The lactate response on the EC network was diminished by TGF-{beta}1 neutralization, indicating a causal relationship between lactate and TGF-{beta}1 in the finely tuned processes of vessel formation and maturation which may also occur in vivo within tumor tissue.

  4. Systemic sclerosis sera affect fibrillin-1 deposition by dermal blood microvascular endothelial cells: therapeutic implications of cyclophosphamide

    PubMed Central

    2013-01-01

    Introduction Systemic sclerosis (SSc) is a connective tissue disorder characterized by endothelial cell injury, autoimmunity and fibrosis. The following three fibrillin-1 alterations have been reported in SSc. (1) Fibrillin-1 microfibrils are disorganized in SSc dermis. (2) Fibrillin-1 microfibrils produced by SSc fibroblasts are unstable. (3) Mutations in the FBN1 gene and anti-fibrillin-1 autoantibodies have been reported in SSc. Fibrillin-1 microfibrils, which are abundantly produced by blood and lymphatic microvascular endothelial cells (B-MVECs and Ly-MVECs, respectively), sequester in the extracellular matrix the latent form of the potent profibrotic cytokine transforming growth factor β (TGF-β). In the present study, we evaluated the effects of SSc sera on the deposition of fibrillin-1 and microfibril-associated glycoprotein 1 (MAGP-1) and the expression of focal adhesion molecules by dermal B-MVECs and Ly-MVECs. Methods Dermal B-MVECs and Ly-MVECs were challenged with sera from SSc patients who were treatment-naïve or under cyclophosphamide (CYC) treatment and with sera from healthy controls. Fibrillin-1/MAGP-1 synthesis and deposition and the expression of αvβ3 integrin/phosphorylated focal adhesion kinase and vinculin/actin were evaluated by immunofluorescence and quantified by morphometric analysis. Results Fibrillin-1 and MAGP-1 colocalized in all experimental conditions, forming a honeycomb pattern in B-MVECs and a dense mesh of short segments in Ly-MVECs. In B-MVECs, fibrillin-1/MAGP-1 production and αvβ3 integrin expression significantly decreased upon challenge with sera from naïve SSc patients compared with healthy controls. Upon challenge of B-MVECs with sera from CYC-treated SSc patients, fibrillin-1/MAGP-1 and αvβ3 integrin levels were comparable to those of cells treated with healthy sera. Ly-MVECs challenged with SSc sera did not differ from those treated with healthy control sera in the expression of any of the molecules assayed

  5. 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

  6. 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

  7. Exposure to GSM RF Fields Does Not Affect Calcium Homeostasis in Human Endothelial Cells, Rat Pheocromocytoma Cells or Rat Hippocampal Neurons

    PubMed Central

    O'Connor, Rodney P.; Madison, Steve D.; Leveque, Philippe; Roderick, H. Llewelyn; Bootman, Martin D.

    2010-01-01

    In the course of modern daily life, individuals are exposed to numerous sources of electromagnetic radiation that are not present in the natural environment. The strength of the electromagnetic fields from sources such as hairdryers, computer display units and other electrical devices is modest. However, in many home and office environments, individuals can experience perpetual exposure to an “electromagnetic smog”, with occasional peaks of relatively high electromagnetic field intensity. This has led to concerns that such radiation can affect health. In particular, emissions from mobile phones or mobile phone masts have been invoked as a potential source of pathological electromagnetic radiation. Previous reports have suggested that cellular calcium (Ca2+) homeostasis is affected by the types of radiofrequency fields emitted by mobile phones. In the present study, we used a high-throughput imaging platform to monitor putative changes in cellular Ca2+ during exposure of cells to 900 MHz GSM fields of differing power (specific absorption rate 0.012–2 W/Kg), thus mimicking the type of radiation emitted by current mobile phone handsets. Data from cells experiencing the 900 Mhz GSM fields were compared with data obtained from paired experiments using continuous wave fields or no field. We employed three cell types (human endothelial cells, PC-12 neuroblastoma and primary hippocampal neurons) that have previously been suggested to be sensitive to radiofrequency fields. Experiments were designed to examine putative effects of radiofrequency fields on resting Ca2+, in addition to Ca2+ signals evoked by an InsP3-generating agonist. Furthermore, we examined putative effects of radiofrequency field exposure on Ca2+ store emptying and store-operated Ca2+ entry following application of the Ca2+ATPase inhibitor thapsigargin. Multiple parameters (e.g., peak amplitude, integrated Ca2+ signal, recovery rates) were analysed to explore potential impact of radiofrequency field

  8. Exposure to GSM RF fields does not affect calcium homeostasis in human endothelial cells, rat pheocromocytoma cells or rat hippocampal neurons.

    PubMed

    O'Connor, Rodney P; Madison, Steve D; Leveque, Philippe; Roderick, H Llewelyn; Bootman, Martin D

    2010-01-01

    In the course of modern daily life, individuals are exposed to numerous sources of electromagnetic radiation that are not present in the natural environment. The strength of the electromagnetic fields from sources such as hairdryers, computer display units and other electrical devices is modest. However, in many home and office environments, individuals can experience perpetual exposure to an "electromagnetic smog", with occasional peaks of relatively high electromagnetic field intensity. This has led to concerns that such radiation can affect health. In particular, emissions from mobile phones or mobile phone masts have been invoked as a potential source of pathological electromagnetic radiation. Previous reports have suggested that cellular calcium (Ca2+) homeostasis is affected by the types of radiofrequency fields emitted by mobile phones. In the present study, we used a high-throughput imaging platform to monitor putative changes in cellular Ca2+ during exposure of cells to 900 MHz GSM fields of differing power (specific absorption rate 0.012-2 W/Kg), thus mimicking the type of radiation emitted by current mobile phone handsets. Data from cells experiencing the 900 Mhz GSM fields were compared with data obtained from paired experiments using continuous wave fields or no field. We employed three cell types (human endothelial cells, PC-12 neuroblastoma and primary hippocampal neurons) that have previously been suggested to be sensitive to radiofrequency fields. Experiments were designed to examine putative effects of radiofrequency fields on resting Ca2+, in addition to Ca2+ signals evoked by an InsP(3)-generating agonist. Furthermore, we examined putative effects of radiofrequency field exposure on Ca2+ store emptying and store-operated Ca2+ entry following application of the Ca2+ATPase inhibitor thapsigargin. Multiple parameters (e.g., peak amplitude, integrated Ca2+ signal, recovery rates) were analysed to explore potential impact of radiofrequency field

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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...

  14. 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

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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

  20. [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

  1. 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

  2. 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

  3. 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...

  4. Coxsackie- and adenovirus receptor (CAR) is expressed in lymphatic vessels in human skin and affects lymphatic endothelial cell function in vitro

    SciTech Connect

    Vigl, Benjamin; Zgraggen, Claudia; Rehman, Nadia; Banziger-Tobler, Nadia E.; Detmar, Michael; Halin, Cornelia

    2009-01-15

    Lymphatic vessels play an important role in tissue fluid homeostasis, intestinal fat absorption and immunosurveillance. Furthermore, they are involved in pathologic conditions, such as tumor cell metastasis and chronic inflammation. In comparison to blood vessels, the molecular phenotype of lymphatic vessels is less well characterized. Performing comparative gene expression analysis we have recently found that coxsackie- and adenovirus receptor (CAR) is significantly more highly expressed in cultured human, skin-derived lymphatic endothelial cells (LECs), as compared to blood vascular endothelial cells. Here, we have confirmed these results at the protein level, using Western blot and FACS analysis. Immunofluorescence performed on human skin confirmed that CAR is expressed at detectable levels in lymphatic vessels, but not in blood vessels. To address the functional significance of CAR expression, we modulated CAR expression levels in cultured LECs in vitro by siRNA- and vector-based transfection approaches. Functional assays performed with the transfected cells revealed that CAR is involved in distinct cellular processes in LECs, such as cell adhesion, migration, tube formation and the control of vascular permeability. In contrast, no effect of CAR on LEC proliferation was observed. Overall, our data suggest that CAR stabilizes LEC-LEC interactions in the skin and may contribute to lymphatic vessel integrity.

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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

  10. Effects of Parietaria judaica pollen extract on human microvascular endothelial cells.

    PubMed

    Taverna, Simona; Flugy, Anna; Colomba, Paolo; Barranca, Marilisa; De Leo, Giacomo; Alessandro, Riccardo

    2008-08-01

    Pollinosis from Parietaria judaica is one of the main causes of allergy in the Mediterranean area. The present study is designed to assess if P. judaica pollens contain bioactive compounds able to elicit a functional response in endothelial cells. We have demonstrated that addition of pollen extract to human lung microvascular endothelial cells (HMVEC-L) induces a modification of cell morphology, actin cytoskeletal rearrangements and an increase in endothelial cell permeability. We further showed that the treatment of endothelial cells with pollen extract causes an increase of E-selectin and VCAM-1 protein levels as well as an increase of IL-8 production. The stimulation of cell-cell adhesion molecules was paralleled by a dose-dependent increase of adhesion of polymorphonuclear cells (PMNs) to HMVEC-L monolayer. Our results suggest for the first time that pollen affect directly endothelial cells (EC) modulating critical functions related to the inflammatory response. PMID:18515075

  11. 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

  12. 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

  13. 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...

  14. [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

  15. 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

  16. 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

  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. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. Insulin Resistance May Contribute to Upregulation of Adhesion Molecules on Endothelial Cells in Psoriatic Plaques.

    PubMed

    Schlüter, Kathrin; Diehl, Sandra; Lang, Victoria; Kaufmann, Roland; Boehncke, Wolf-Henning; Bürger, Claudia

    2016-02-01

    Psoriasis primarily affects the skin, but also has a systemic dimension and is associated with severe comorbidities. Since endothelial cells play an important role in psoriasis as well as in the development of cardiovascular comorbidities, we investigated whether a common mechanism, namely cytokine-induced insulin resistance, underlies both pathologies. Activation of the insulin pathway was studied in psoriatic skin and dermal endothelial cells. Expression of adhesion molecules was assessed by flow cytometry, as well as their biological function in flow chamber experiments. The phosphorylation status of Akt, a central kinase in the insulin pathway, suggests that endothelial cells within psoriatic plaques are rendered insulin resistant by pro-inflammatory cytokines. Insulin counteracts the expression of adhesion molecules, but has limited effects on interactions between T cells and endothelial cells. Pro-inflammatory cytokines induce insulin resistance in endothelial cells, which may contribute to the development of the inflammatory infiltrate in psoriasis. PMID:26315601

  10. Conserved arginine residues in the carboxyl terminus of the equine arteritis virus E protein may play a role in heparin binding but may not affect viral infectivity in equine endothelial cells.

    PubMed

    Lu, Zhengchun; Sarkar, Sanjay; Zhang, Jianqiang; Balasuriya, Udeni B R

    2016-04-01

    Equine arteritis virus (EAV), the causative agent of equine viral arteritis, has relatively broad cell tropism in vitro. In horses, EAV primarily replicates in macrophages and endothelial cells of small blood vessels. Until now, neither the cellular receptor(s) nor the mechanism(s) of virus attachment and entry have been determined for this virus. In this study, we investigated the effect of heparin on EAV infection in equine endothelial cells (EECs). Heparin, but not other glycosaminoglycans, could reduce EAV infection up to 93 %. Sequence analysis of the EAV E minor envelope protein revealed a conserved amino acid sequence (52 RSLVARCSRGARYR 65) at the carboxy terminus of the E protein, which was predicted to be the heparin-binding domain. The basic arginine (R) amino acid residues were subsequently mutated to glycine by site-directed mutagenesis of ORF2a in an E protein expression vector and an infectious cDNA clone of EAV. Two single mutations in E (R52G and R57G) did not affect the heparin-binding capability, whereas the E double mutation (R52,60G) completely eliminated the interaction between the E protein and heparin. Although the mutant R52,60G EAV did not bind heparin, the mutations did not completely abolish infectivity, indicating that heparin is not the only critical factor for EAV infection. This also suggested that other viral envelope protein(s) might be involved in attachment through heparin or other cell-surface molecules, and this warrants further investigation. PMID:26739582

  11. 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

  12. 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

  13. Density enhanced phosphatase-1 down-regulates urokinase receptor surface expression in confluent endothelial cells

    PubMed Central

    Brunner, Patrick M.; Heier, Patricia C.; Mihaly-Bison, Judit; Priglinger, Ute; Binder, Bernd R.

    2011-01-01

    VEGF165, the major angiogenic growth factor, is known to activate various steps in proangiogenic endothelial cell behavior, such as endothelial cell migration and invasion, or endothelial cell survival. Thereby, the urokinase-type plasminogen activator (uPA) system has been shown to play an essential role not only by its proteolytic capacities, but also by induction of intracellular signal transduction. Therefore, expression of its cell surface receptor uPAR is thought to be an essential regulatory mechanism in angiogenesis. We found that uPAR expression on the surface of confluent endothelial cells was down-regulated compared with subconfluent proliferating endothelial cells. Regulation of uPAR expression was most probably affected by extracellular signal-regulated kinase 1/2 (ERK1/2) activation, a downstream signaling event of the VEGF/VEGF-receptor system. Consistently, the receptor-like protein tyrosine phosphatase DEP-1 (density enhanced phosphatase-1/CD148), which is abundantly expressed in confluent endothelial cells, inhibited the VEGF-dependent activation of ERK1/2, leading to down-regulation of uPAR expression. Overexpression of active ERK1 rescued the DEP-1 effect on uPAR. That DEP-1 plays a biologic role in angiogenic endothelial cell behavior was demonstrated in endothelial cell migration, proliferation, and capillary-like tube formation assays in vitro. PMID:21304107

  14. 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

  15. Role of endothelial cells in bovine mammary gland health and disease.

    PubMed

    Ryman, Valerie E; Packiriswamy, Nandakumar; Sordillo, Lorraine M

    2015-12-01

    The bovine mammary gland is a dynamic and complex organ composed of various cell types that work together for the purpose of milk synthesis and secretion. A layer of endothelial cells establishes the blood-milk barrier, which exists to facilitate the exchange of solutes and macromolecules necessary for optimal milk production. During bacterial challenge, however, endothelial cells divert some of their lactation function to protect the underlying tissue from damage by initiating inflammation. At the onset of inflammation, endothelial cells tightly regulate the movement of plasma components and leukocytes into affected tissue. Unfortunately, endothelial dysfunction as a result of exacerbated or sustained inflammation can negatively affect both barrier integrity and the health of surrounding extravascular tissue. The objective of this review is to highlight the role of endothelial cells in supporting milk production and regulating optimal inflammatory responses. The consequences of endothelial dysfunction and sustained inflammation on milk synthesis and secretion are discussed. Given the important role of endothelial cells in orchestrating the inflammatory response, a better understanding of endothelial function during mastitis may support development of targeted therapies to protect bovine mammary tissue and mammary endothelium. PMID:26303748

  16. 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.

  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. 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.

  20. Tumor endothelial marker 5 expression in endothelial cells during capillary morphogenesis is induced by the small GTPase Rac and mediates contact inhibition of cell proliferation

    SciTech Connect

    Vallon, Mario; Rohde, Franziska; Janssen, Klaus-Peter; Essler, Markus

    2010-02-01

    Tumor endothelial marker (TEM) 5 is an adhesion G-protein-coupled receptor upregulated in endothelial cells during tumor and physiologic angiogenesis. So far, the mechanisms leading to upregulation of TEM5 and its function during angiogenesis have not been identified. Here, we report that TEM5 expression in endothelial cells is induced during capillary-like network formation on Matrigel, during capillary morphogenesis in a three-dimensional collagen I matrix, and upon confluence on a two-dimensional matrix. TEM5 expression was not induced by a variety of soluble angiogenic factors, including VEGF and bFGF, in subconfluent endothelial cells. TEM5 upregulation was blocked by toxin B from Clostridium difficile, an inhibitor of the small GTPases Rho, Rac, and Cdc42. The Rho inhibitor C3 transferase from Clostridium botulinum did not affect TEM5 expression, whereas the Rac inhibitor NSC23766 suppressed TEM5 upregulation. An excess of the soluble TEM5 extracellular domain or an inhibitory monoclonal TEM5 antibody blocked contact inhibition of endothelial cell proliferation resulting in multilayered islands within the endothelial monolayer and increased vessel density during capillary formation. Based on our results we conclude that TEM5 expression during capillary morphogenesis is induced by the small GTPase Rac and mediates contact inhibition of proliferation in endothelial cells.

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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.

  7. Participation of glomerular endothelial cells in the capillary repair of glomerulonephritis.

    PubMed Central

    Iruela-Arispe, L.; Gordon, K.; Hugo, C.; Duijvestijn, A. M.; Claffey, K. P.; Reilly, M.; Couser, W. G.; Alpers, C. E.; Johnson, R. J.

    1995-01-01

    In many glomerular diseases severe injury to the mesangium may occur, leading to matrix dissolution and damage to the glomerular capillaries. Although the destruction of glomerular architecture may lead to permanent injury, in some cases spontaneous recovery occurs. The mechanisms that mediate this recovery are unknown. In this study we provide evidence for glomerular capillary repair (angiogenesis) in the adult injured glomerulus. Injection of anti-Thy 1 antibody into rats results in severe mesangiolysis with capillary ballooning, microaneurysm formation, and loss of endothelial cells in addition to mesangial cells. Although mesangial proliferation is a major response to injury, proliferation of endothelial cells also can be documented from days 2 to 14 in association with repair of the capillaries. The endothelial cell proliferation peaks on days 2 and 7, when it is seven- to ninefold greater than normal. Many of the endothelial cells display morphological features of angiogenesis. The initial wave of endothelial cell proliferation can be reduced by 40% with neutralizing anti-basic fibroblast growth factor antibodies (P < 0.001). The later glomerular endothelial cell proliferation is associated with upregulated expression of vascular permeability factor/endothelial cell growth factor (VPF/VEGF) and an increase of flk, a VPF/VEGF receptor. Although PDGF is expressed in this model, anti-PDGF antibody treatment did not affect the endothelial cell proliferative response. In summary, glomerular endothelial cells have an active role in the glomerular response to injury. Glomeruli are capable of healing microaneurysms, and the mechanism involves basic fibroblast growth factor- and VPF/VEGF-mediated endothelial proliferative responses. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 PMID:7495296

  8. RhoA GTPase regulates radiation-induced alterations in endothelial cell adhesion and migration

    SciTech Connect

    Rousseau, Matthieu; Gaugler, Marie-Helene; Rodallec, Audrey; Bonnaud, Stephanie; Paris, Francois; Corre, Isabelle

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer We explore the role of RhoA in endothelial cell response to ionizing radiation. Black-Right-Pointing-Pointer RhoA is rapidly activated by single high-dose of radiation. Black-Right-Pointing-Pointer Radiation leads to RhoA/ROCK-dependent actin cytoskeleton remodeling. Black-Right-Pointing-Pointer Radiation-induced apoptosis does not require the RhoA/ROCK pathway. Black-Right-Pointing-Pointer Radiation-induced alteration of endothelial adhesion and migration requires RhoA/ROCK. -- Abstract: Endothelial cells of the microvasculature are major target of ionizing radiation, responsible of the radiation-induced vascular early dysfunctions. Molecular signaling pathways involved in endothelial responses to ionizing radiation, despite being increasingly investigated, still need precise characterization. Small GTPase RhoA and its effector ROCK are crucial signaling molecules involved in many endothelial cellular functions. Recent studies identified implication of RhoA/ROCK in radiation-induced increase in endothelial permeability but other endothelial functions altered by radiation might also require RhoA proteins. Human microvascular endothelial cells HMEC-1, either treated with Y-27632 (inhibitor of ROCK) or invalidated for RhoA by RNA interference were exposed to 15 Gy. We showed a rapid radiation-induced activation of RhoA, leading to a deep reorganisation of actin cytoskeleton with rapid formation of stress fibers. Endothelial early apoptosis induced by ionizing radiation was not affected by Y-27632 pre-treatment or RhoA depletion. Endothelial adhesion to fibronectin and formation of focal adhesions increased in response to radiation in a RhoA/ROCK-dependent manner. Consistent with its pro-adhesive role, ionizing radiation also decreased endothelial cells migration and RhoA was required for this inhibition. These results highlight the role of RhoA GTPase in ionizing radiation-induced deregulation of essential endothelial

  9. 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

  10. 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

  11. 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

  12. Three electrophysiological phenotypes of cultured human umbilical vein endothelial cells.

    PubMed

    Yu, K; Ruan, D Y; Ge, S Y

    2002-09-01

    The conventional whole cell patch-clamp technique was used to measure the resting membrane conductance and membrane currents of nonstimulated cultured human umbilical vein endothelial cells (HUVECs) in different ionic conditions. Three electrophysiological phenotypes of cultured HUVECs (n = 122) were determined: first, 20% of cells as type I mainly displaying the inwardly rectifying potassium current (IKi); second, 38% of cells as type II in which IKi was super-posed on a TEA-sensitive, delayed rectifying current; third, 27% of cells as type III predominantly displaying the outwardly rectifying current which was sensitive to TEA and slightly inhibited by a chloride channel blocker niflumic acid (N.A.). In cells of type I, the mean zero-current potential (V0) was dependent on extracellular K+ ([K+]o) but not on Cl-, indicating major permeability to K+. Whereas V0 of type II was also affected by extracellular Cl- ([Cl-]o), indicating the contribution of an outward Cl- current in setting V0. The cells of type III were not sensitive to decrease of [Cl-]o and the outward current was activated in a relative stable voltage range. This varying phenotypic expression and multipotential behavior of HUVECs suggests that the electrical features of HUVEC may be primarily determined by embryonic origin and local effect of the microenvironment. This research provided the detailed electrophysiological knowledge of the endothelial cells. PMID:12537354

  13. 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

  14. 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

  15. Glioblastoma microvesicles promote endothelial cell proliferation through Akt/beta-catenin pathway.

    PubMed

    Liu, Shihai; Sun, Junfeng; Lan, Qing

    2014-01-01

    Glioblastoma tumor cells release microvesicles, which contain mRNA, miRNA and angiogenic proteins. These tumor-derived microvesicles transfer genetic information and proteins to normal cells. Previous reports demonstrated that the increased microvesicles in cerebrospinal fluid (CSF) of patients with glioblastoma up-regulate procoagulant activity. The concentration of microvesicles was closely related to thromboembolism incidence and clinical therapeutic effects of glioblastoma patients. However, it is still not clear how CSF microvesicles and what factors affect glioblastoma development. In this study, we collected the plasma and CSF from glioblastoma patients and healthy volunteers. Microvesicles acquired from serum or CSF were added to cultured endothelial cells. And the effects of these microvesicles on endothelial cells were examined. Our results showed that microvesicles from CSF of patients, but not from circulating blood, promoted endothelial cells migration and proliferation in vitro. In addition, the degree of endothelial cell proliferation triggered by microvesicles from CSF was reduced when treated with siRNA targeting Akt/beta-catenin, suggesting that the Akt/beta-catenin pathway is involved in the microvesicle-initiated endothelial cell proliferation. In conclusion, glioblastoma mainly affects microvesicles within CSF without showing significant impact on microvesicles in circulating blood. Microvesicles from the CSF of glioblastoma patients may initiate endothelial cell growth and thus promote cell invasion. This effect may be directly exerted by activated Akt/beta-catenin pathway. PMID:25197356

  16. 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

  17. 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

  18. 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

  19. Matrin 3 as a key regulator of endothelial cell survival

    SciTech Connect

    Przygodzka, Patrycja; Boncela, Joanna; Cierniewski, Czeslaw S.

    2011-04-01

    Matrin 3 is an integral component of nuclear matrix architecture that has been implicated in interacting with other nuclear proteins and thus modulating the activity of proximal promoters. In this study, we evaluated the contribution of this protein to proliferation of endothelial cells. To selectively modulate matrin 3 expression, we used siRNA oligonucleotides and transfection of cells with a pEGFP-N1-Mtr3. Our data indicate that downregulation of matrin 3 is responsible for reduced proliferation and leads to necrosis of endothelial cells. This conclusion is supported by observations that reducing matrin 3 expression results in (a) producing signs of necrosis detected by PI staining, LDH release, and scatter parameters in flow cytometry, (b) affecting cell cycle progression. It does not cause (c) membrane asymmetry of cells as indicated by lack of Annexin V binding as well as (d) activation of caspase 3 and cleavage of PARP. We conclude that matrin 3 plays a significant role in controlling cell growth and proliferation, probably via formation of complexes with nuclear proteins that modulate pro- and antiapoptotic signaling pathways. Thus, degradation of matrin 3 may be a switching event that induces a shift from apoptotic to necrotic death of cells.

  20. 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.

  1. 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

  2. Cell biology of diabetic nephropathy: Roles of endothelial cells, tubulointerstitial cells and podocytes

    PubMed Central

    Maezawa, Yoshiro; Takemoto, Minoru; Yokote, Koutaro

    2015-01-01

    Diabetic nephropathy is the major cause of end-stage renal failure throughout the world in both developed and developing countries. Diabetes affects all cell types of the kidney, including endothelial cells, tubulointerstitial cells, podocytes and mesangial cells. During the past decade, the importance of podocyte injury in the formation and progression of diabetic nephropathy has been established and emphasized. However, recent findings provide additional perspectives on pathogenesis of diabetic nephropathy. Glomerular endothelial damage is already present in the normoalbuminuric stage of the disease when podocyte injury starts. Genetic targeting of mice that cause endothelial injury leads to accelerated diabetic nephropathy. Tubulointerstitial damage, previously considered to be a secondary effect of glomerular protein leakage, was shown to have a primary significance in the progression of diabetic nephropathy. Emerging evidence suggests that the glomerular filtration barrier and tubulointerstitial compartment is a composite, dynamic entity where any injury of one cell type spreads to other cell types, and leads to the dysfunction of the whole apparatus. Accumulation of novel knowledge would provide a better understanding of the pathogenesis of diabetic nephropathy, and might lead to a development of a new therapeutic strategy for the disease. PMID:25621126

  3. The coffee diterpene kahweol inhibits tumor necrosis factor-{alpha}-induced expression of cell adhesion molecules in human endothelial cells

    SciTech Connect

    Kim, Hyung Gyun; Kim, Ji Young; Hwang, Yong Pil; Lee, Kyung Jin; Lee, Kwang Youl; Kim, Dong Hee; Kim, Dong Hyun; Jeong, Hye Gwang . E-mail: hgjeong@chosun.ac.kr

    2006-12-15

    Endothelial cells produce adhesion molecules after being stimulated with various inflammatory cytokines. These adhesion molecules play an important role in the development of atherogenesis. Recent studies have highlighted the chemoprotective and anti-inflammatory effects of kahweol, a coffee-specific diterpene. This study examined the effects of kahweol on the cytokine-induced monocyte/human endothelial cell interaction, which is a crucial early event in atherogenesis. Kahweol inhibited the adhesion of TNF{alpha}-induced monocytes to endothelial cells and suppressed the TNF{alpha}-induced protein and mRNA expression of the cell adhesion molecules, VCAM-1 and ICAM-1. Furthermore, kahweol inhibited the TNF{alpha}-induced JAK2-PI3K/Akt-NF-{kappa}B activation pathway in these cells. Overall, kahweol has anti-inflammatory and anti-atherosclerotic activities, which occurs partly by down-regulating the pathway that affects the expression and interaction of the cell adhesion molecules on endothelial cells.

  4. Effects of surface viscoelasticity on cellular responses of endothelial cells

    PubMed Central

    Hosseini, Motahare-Sadat; Katbab, Ali Asghar

    2014-01-01

    Background: One area of nanoscience deals with nanoscopic interactions between nanostructured materials and biological systems. To elucidate the effects of the substrate surface morphology and viscoelasticity on cell proliferation, fractal analysis was performed on endothelial cells cultured on nanocomposite samples based on silicone rubber (SR) and various concentrations of organomodified nanoclay (OC). Methods: The nanoclay/SR ratio was tailored to enhance cell behavior via changes in sample substrate surface roughness and viscoelasticity. Results: Surface roughness of the cured SR filled with negatively-charged nanosilicate layers had a greater effect than elasticity on cell growth. The surface roughness of SR nanocomposite samples increased with increasing the OC content, leading to enhanced cell growth and extracellular matrix (ECM) remodeling. This was consistent with the decrease in SR segmental motions and damping factor as the primary viscoelastic parameters by the nanosilicate layers with increasing clay concentrations. Conclusions: The inclusion of clay nanolayers affected the growth and behavior of endothelial cells on microtextured SR. PMID:26989733

  5. 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

  6. 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

  7. Differential regulation of angiopoietin 1 and angiopoietin 2 during dengue virus infection of human umbilical vein endothelial cells: implications for endothelial hyperpermeability.

    PubMed

    Ong, Siew Pei; Ng, Mah Lee; Chu, Justin Jang Hann

    2013-12-01

    Infection with dengue virus (DV) can result in dengue hemorrhagic fever and dengue shock syndrome, where patients suffer from bleeding and plasma leakage involving endothelial cells. Angiopoietins (Ang) 1 and 2 are important angiogenic factors that affect endothelial barrier integrity. In this study, DV was observed to induce endothelial leakage at multiplicity of infection of 10 in primary human umbilical vein endothelial cells (HUVEC) with interendothelial gap formation. Immunostaining of vascular endothelial cadherin (VE-cadherin) and zona occludin 1 (ZO-1) showed the absence of these endothelial junctional proteins at the cell-cell contact zones between adjacent cells. In addition, Ang1 that is required for protecting against endothelial hyperpermeability was found to be down-regulated during DV infection. Treatment with increasing concentrations of recombinant Ang1 was shown to prevent DV-induced endothelial hyperpermeability in a dose-dependent manner by preventing the down-regulation of VE-cadherin and ZO-1 at cell membrane. In contrast, the expression of Ang2, the natural antagonist of Ang1, was observed to be up-regulated during DV infection. Recombinant Ang2 added to HUVEC at non-toxic concentrations showed decreased in transendothelial electrical resistance reading and the down-regulation of VE-cadherin and ZO-1. These findings suggest that DV reduces the expression of Ang1 and enhances the expression of Ang2 in endothelial cells and that this imbalance of Ang 1 and Ang 2 may play a contributing role to the increased permeability of human primary endothelial cells during DV infection. PMID:23989887

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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

  17. Signal transduction in endothelial cells by the angiogenesis inhibitor histidine-rich glycoprotein targets focal adhesions

    SciTech Connect

    Lee, Chunsik; Dixelius, Johan; Thulin, Asa; Kawamura, Harukiyo; Claesson-Welsh, Lena; Olsson, Anna-Karin . E-mail: Anna-Karin.Olsson@genpat.uu.se

    2006-08-01

    Histidine-rich glycoprotein (HRGP) is an abundant heparin-binding plasma protein. We have shown that a fragment released from the central histidine/proline-rich (His/Pro-rich) domain of HRGP blocks endothelial cell migration in vitro and vascularization and growth of murine fibrosarcoma in vivo. The minimal active HRGP domain exerting the anti-angiogenic effect was recently narrowed down to a 35 amino acid peptide, HRGP330, derived from the His/Pro-rich domain of HRGP. By use of a signal transduction antibody array representing 400 different signal transduction molecules, we now show that HRGP and the synthetic peptide HRGP330 specifically induce tyrosine phosphorylation of focal adhesion kinase and its downstream substrate paxillin in endothelial cells. HRGP/HRGP330 treatment of endothelial cells induced disruption of actin stress fibers, a process reversed by treatment of cells with the FAK inhibitor geldanamycin. In addition, VEGF-mediated endothelial cell tubular morphogenesis in a three-dimensional collagen matrix was inhibited by HRGP and HRGP330. In contrast, VEGF-induced proliferation was not affected by HRGP or HRGP330, demonstrating the central role of cell migration during tube formation. In conclusion, our data show that HRGP targets focal adhesions in endothelial cells, thereby disrupting the cytoskeletal organization and the ability of endothelial cells to assemble into vessel structures.

  18. [Dynamics of the cell cycle in human endothelial cell culture infected with influenza virus].

    PubMed

    Prochukhanova, A R; Lyublinskaya, O G; Azarenok, A A; Nazarova, A V; Zenin, V V; Zhilinskaya, I N

    2015-01-01

    Cell cycle in a culture of endothelial cells EAhy 926 infected with influenza virus was investigated. Cytometric analysis of culture, synchronized using contact inhibition, has shown that the exposure to the influenza virus in cells EAhy 926 lengthened S-phase of the cell cycle. This result has been tested and proven on culture EAhy 926 treated with nocodazole. Compared with lung carcinoma cells A549, in which influenza virus provokes the arrest of G0/G1 phase of the cycle, elongation of S-phase of cycle at a similar infection of endothelial culture EAhy 926 indicates that the influenza virus differently affects the dynamics of the cell cycle according to the origin of the infected culture. PMID:26021172

  19. 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

  20. Effect of selected flavones on cancer and endothelial cells.

    PubMed

    Pilátová, Martina; Stupáková, Viktória; Varinská, Lenka; Sarisský, Marek; Mirossay, Ladislav; Mirossay, Andrej; Gál, Peter; Kraus, Vladimír; Dianisková, Katarína; Mojzis, Ján

    2010-06-01

    In our study we used quercetin (3,3 ,4 ,5,7-pentahydroxyflavone) as the reference standard to compare antiproliferative and antiangiogenic effects of chrysin (5,7-dihydroxyflavone) and 3-hydroxyflavone. Our data indicates that chrysin and 3-hydroxyflavone showed significantly higher cytotoxic effect than reference standard quercetin. These tested agents significantly decreased cell survival with the efficacy of 65-85% at the concentration 100 micromol/l for HUVEC, lung carcinoma and leukemic cells being the most sensitive. Cell cycle analysis indicates that quercetin and 3-hydroxyflavone might affect the cell cycle of Jurkat cells by a similar or the same mechanism of action which lead to G2/M arrest as well as to an increase in sub-G0/G1 fraction. Treatment of Jurkat cells with chrysin resulted only increase in the fraction of cells with sub-G0/G1 DNA content, which is considered to be a marker of apoptotic cell death. Apoptosis was confirmed by DNA fragmentation and by staining with annexin V. All three tested flavones inhibited endothelial cell migration after 24 h of incubation at a concentration 100 micromol/l. At a lower concentration (10 micromol/l) only quercetin significantly inhibited migration of endothelial cells. Furthermore, in our experiments decreased secretion of matrix metalloproteinases (MMP-2 and MMP-9) was observed after a 72 h treatment with quercetin. No decrease in secretion of MMP-2 and MMP-9 was seen after chrysin and 3-hydroxyflavone treatment. On the other hand, our results showed that none of three flavonoids blocked microcapillary tube formation. Further studies are necessary to investigate the mechanism of action and to find out the relationship between the structure, character and position of substituents of natural substances and their biological activities. PMID:20577025

  1. 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.

  2. 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

  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. Ozone inhibits endothelial cell cyclooxygenase activity through formation of hydrogen peroxide

    SciTech Connect

    Madden, M.C.; Eling, T.E.; Friedman, M.

    1987-09-01

    We have previously demonstrated that a 2H exposure of cultured pulmonary endothelial cells to ozone (0.0-1.0 ppm) in-vitro resulted in a concentration-dependent reduction of endothelial prostacyclin production (90% decrease at the 1.0 ppm level). Ozone-exposed endothelial cells, incubated with 20 uM arachidonate, also demonstrated a significant inhibition of prostacyclin synthesis. To further examine the mechanisms of the inhibition of prostacyclin synthesis, bovine pulmonary endothelial cells were exposed to 1.0 ppm ozone for 2H. A significant decrease in prostacyclin synthesis was found within 5 min of exposure (77 +/- 36% of air-exposed control values, p less than 0.05). Endothelial prostacyclin synthesis returned to baseline levels by 12H after ozone exposure, a time point which was similar to the recovery time of unexposed endothelium treated with 0.5 uM acetylsalicylic acid. Incubation of endothelial cells, previously exposed to 1.0 ppm ozone for 2 hours, with 4 uM PGH2 resulted in restoration of essentially normal prostacyclin synthesis. When endothelial cells were co-incubated with catalase (5 U/ml) during ozone exposure, no inhibition of prostacyclin synthesis was observed. Co-incubation with either heat-inactivated catalase or superoxide dismutase (10 U/ml) did not affect the ozone-induced inhibition of prostacyclin synthesis. These data suggest that H/sub 2/O/sub 2/ is a major toxic species produced in endothelial cells during ozone exposure and responsible for the inhibition of endothelial cyclooxygenase activity.

  5. 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

  6. 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...

  7. 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

  8. Endometrial endothelial cell proliferation in long-term users of subdermal levonorgestrel.

    PubMed

    Goodger, A M; Rogers, P A; Affandi, B

    1994-09-01

    The aim of the present study was to quantify endothelial cell proliferation (a component of angiogenesis) using immunohistochemistry, in the endometrium of users of subdermal levonorgestrel (Norplant). It was postulated that the increased endometrial microvascular density seen in Norplant users, compared to normally cycling women, was associated with an increased rate of endothelial cell proliferation. The results, however, showed that the endometrial endothelial cell proliferative index of Norplant users (0.39 +/- 0.16%; mean +/- SEM) was significantly reduced compared to that seen in normally cycling women (8.99 +/- 1.64). At the same time, total numbers of endometrial endothelial cells per mm2 in Norplant users (317.40 +/- 13.88) were significantly higher than in normally cycling women (223.35 +/- 10.31). It is possible that in the endometrium with levonorgestrel use, there is either a reduced rate of regression of the blood vessels relative to the rest of the tissue, or there is a reduced rate of endothelial cell death or turnover. Peripheral oestrogen and progesterone concentrations, bleeding pattern over the previous 90 days, and the histological appearance of the endometrium did not appear to be associated with the endothelial cell proliferative index. The results suggest that subdermal levonorgestrel use affects the mechanisms that dictate the normal relationship between endometrial blood vessel growth and regression, and the surrounding non-vascular tissue. PMID:7530724

  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. Effects of Gravitational Mechanical Unloading in Endothelial Cells: Association between Caveolins, Inflammation and Adhesion Molecules

    PubMed Central

    Grenon, S. Marlene; Jeanne, Marion; Aguado-Zuniga, Jesus; Conte, Michael S.; Hughes-Fulford, Millie

    2013-01-01

    Mechanical forces including gravity affect endothelial cell (ECs) function, and have been implicated in vascular disease as well as physiologic changes associated with low gravity environments. The goal of this study was to investigate the impact of gravitational mechanical unloading on ECs phenotype as determined by patterns of gene expression. Human umbilical vascular endothelial cells were exposed to 1-gravity environment or mechanical unloading (MU) for 24 hours, with or without periods of mechanical loading (ML). MU led to a significant decrease in gene expression of several adhesion molecules and pro-inflammatory cytokines. On the contrary, eNOS, Caveolin-1 and -2 expression were significantly increased with MU. There was a decrease in the length and width of the cells with MU. Addition of ML during the MU period was sufficient to reverse the changes triggered by MU. Our results suggest that gravitational loading could dramatically affect vascular endothelial cell function. PMID:23511048

  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. 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

  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. 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

  17. 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.

  18. Interactions between endothelial cells and T cells modulate responses to mixed neutron/gamma radiation.

    PubMed

    Cary, Lynnette H; Noutai, Daniel; Salber, Rudolph E; Williams, Margaret S; Ngudiankama, Barbara F; Whitnall, Mark H

    2014-06-01

    caspase 3. Irradiation of Jurkat cells caused a G2/M arrest and increased adherence to HUVEC. When co-cultured with HUVEC, irradiated Jurkat cells exhibited G0/G1 arrest and increased apoptosis. The data indicate that gene expression and cell function of endothelial cells and hematopoietic cells are influenced by radiation and by interactions between the two cell types. These phenomena may affect the success of therapies for ARS and cancer. PMID:24828109

  19. Oxidized LDL signals through Rho-GTPase to induce endothelial cell stiffening and promote capillary formation.

    PubMed

    Oh, Myung-Jin; Zhang, Chongxu; LeMaster, Elizabeth; Adamos, Crystal; Berdyshev, Evgeny; Bogachkov, Yedida; Kohler, Erin E; Baruah, Jugajyoti; Fang, Yun; Schraufnagel, Dean E; Wary, Kishore K; Levitan, Irena

    2016-05-01

    Endothelial biomechanics is emerging as a key factor in endothelial function. Here, we address the mechanisms of endothelial stiffening induced by oxidized LDL (oxLDL) and investigate the role of oxLDL in lumen formation. We show that oxLDL-induced endothelial stiffening is mediated by CD36-dependent activation of RhoA and its downstream target, Rho kinase (ROCK), via inhibition of myosin light-chain phosphatase (MLCP) and myosin light-chain (MLC)2 phosphorylation. The LC-MS/MS analysis identifies 7-ketocholesterol (7KC) as the major oxysterol in oxLDL. Similarly to oxLDL, 7KC induces RhoA activation, MLCP inhibition, and MLC2 phosphorylation resulting in endothelial stiffening. OxLDL also facilitates formation of endothelial branching networks in 3D collagen gels in vitro and induces increased formation of functional blood vessels in a Matrigel plug assay in vivo. Both effects are RhoA and ROCK dependent. An increase in lumen formation was also observed in response to pre-exposing the cells to 7KC, an oxysterol that induces endothelial stiffening, but not to 5α,6α epoxide that does not affect endothelial stiffness. Importantly, loading cells with cholesterol prevented oxLDL-induced RhoA activation and the downstream signaling cascade, and reversed oxLDL-induced lumen formation. In summary, we show that oxLDL-induced endothelial stiffening is mediated by the CD36/RhoA/ROCK/MLCP/MLC2 pathway and is associated with increased endothelial angiogenic activity. PMID:26989083

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. Substituted oxines inhibit endothelial cell proliferation and angiogenesis†

    PubMed Central

    Bhat, Shridhar; Shim, Joong Sup; Zhang, Feiran; Chong, Curtis Robert; Liu, Jun O.

    2013-01-01

    Two substituted oxines, nitroxoline (5) and 5-chloroquinolin-8-yl phenylcarbamate (22), were identified as hits in a high-throughput screen aimed at finding new anti-angiogenic agents. In a previous study, we have elucidated the molecular mechanism of antiproliferative activity of nitroxoline in endothelial cells, which comprises of a dual inhibition of type 2 human methionine aminopeptidase (MetAP2) and sirtuin 1 (SIRT1). Structure–activity relationship study (SAR) of nitroxoline offered many surprises where minor modifications yielded oxine derivatives with increased potency against human umbilical vein endothelial cells (HUVEC), but with entirely different as yet unknown mechanisms. For example, 5-nitrosoquinolin-8-ol (33) inhibited HUVEC growth with sub-micromolar IC50, but did not affect MetAP2 or MetAP1, and it only showed weak inhibition against SIRT1. Other sub-micromolar inhibitors were derivatives of 5-aminoquinolin-8-ol (34) and 8-sulfonamidoquinoline (32). A sulfamate derivative of nitroxoline (48) was found to be more potent than nitroxoline with the retention of activities against MetAP2 and SIRT1. The bioactivity of the second hit, micromolar HUVEC and MetAP2 inhibitor carbamate 22 was improved further with an SAR study culminating in carbamate 24 which is a nanomolar inhibitor of HUVEC and MetAP2. PMID:22391578

  6. 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

  7. 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

  8. Advanced glycation end‑products affect the cytoskeletal structure of rat glomerular endothelial cells via the Ras‑related C3 botulinum toxin substrate 1 signaling pathway.

    PubMed

    Lan, Lei; Han, Yongsheng; Ren, Wei; Jiang, Jielong; Wang, Peng; Hu, Zhao

    2015-06-01

    The present study aimed to determine the molecular mechanisms leading to the production of advanced glycation end‑products (AGEs) and their effect on the morphology and function of rat glomerular capillary endothelial cells (GECs). Primary rat GECs were treated with AGE‑modified human serum albumin (AGE‑HSA) and divided into groups according to AGE concentration and treatment time. The structure and distribution of cytoskeletal protein F‑actin and the cortical actin binding protein, cortactin, were analyzed using immunofluorescence and confocal microscopy. As the Ras‑related C3 botulinum toxin substrate 1 (Rac1) signaling pathway was previously identified to be involved in mediating the contraction of endothelial actin‑myosin activity, Rac1 was examined subsequent to treatment of the cells with the Rac1 agonist 2'‑O‑methyladenosine‑3',5'‑cyclic monophosphate (O‑Me‑cAMP) for 1 h using a pull‑down assay. Cell permeability was determined by the leakage rate of a fluorescein isothiocyanate fluorescent marker protein. AGE‑HSA treatment resulted in alterations in the structure and distribution of F‑actin and cortactin in a dose‑ and time‑dependent manner, while no effect was observed with HSA alone. The effect of AGE on the cytoskeleton was inhibited by the addition of O‑Me‑cAMP. AGE‑HSA significantly reduced the level of Rac1 activity (P<0.05); however, no effect was observed on total protein levels. Furthermore, AGE‑HSA treatment led to a significant increase in the permeability of endothelial cells (P<0.01), which was inhibited by O‑Me‑cAMP (P<0.01). The Rac1 signaling pathway is thus suggested to serve an important function in mediating AGE‑induced alterations in GEC morphology and function. PMID:25672514

  9. 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

  10. 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

  11. 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

  12. How to utilize Ca2+ signals to rejuvenate the repairative phenotype of senescent endothelial progenitor cells in elderly patients affected by cardiovascular diseases: a useful therapeutic support of surgical approach?

    PubMed Central

    2013-01-01

    Endothelial dysfunction or loss is the early event that leads to a host of severe cardiovascular diseases, such as atherosclerosis, hypertension, brain stroke, myocardial infarction, and peripheral artery disease. Ageing is regarded among the most detrimental risk factor for vascular endothelium and predisposes the subject to atheroscleorosis and inflammatory states even in absence of traditional comorbid conditions. Standard treatment to restore blood perfusion through stenotic arteries are surgical or endovascular revascularization. Unfortunately, ageing patients are not the most amenable candidates for such interventions, due to high operative risk or unfavourable vascular involvement. It has recently been suggested that the transplantation of autologous bone marrow-derived endothelial progenitor cells (EPCs) might constitute an alternative and viable therapeutic option for these individuals. Albeit pre-clinical studies demonstrated the feasibility of EPC-based therapy to recapitulate the diseased vasculature of young and healthy animals, clinical studies provided less impressive results in old ischemic human patients. One hurdle associated to this kind of approach is the senescence of autologous EPCs, which are less abundant in peripheral blood and display a reduced pro-angiogenic activity. Conversely, umbilical cord blood (UCB)-derived EPCs are more suitable for cellular therapeutics due to their higher frequency and sensitivity to growth factors, such as vascular endothelial growth factor (VEGF). An increase in intracellular Ca2+ concentration is central to EPC activation by VEGF. We have recently demonstrated that the Ca2+ signalling machinery driving the oscillatory Ca2+ response to this important growth factor is different in UCB-derived EPCs as compared to their peripheral counterparts. In particular, we focussed on the so-called endothelial colony forming cells (ECFCs), which are the only EPC population belonging to the endothelial lineage and able to

  13. 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

  14. Inactivation of the Human Cytomegalovirus US20 Gene Hampers Productive Viral Replication in Endothelial Cells

    PubMed Central

    Cavaletto, Noemi; Luganini, Anna

    2015-01-01

    ABSTRACT The human cytomegalovirus (HCMV) US12 gene family includes a group of 10 contiguous genes (US12 to US21) encoding predicted seven-transmembrane-domain (7TMD) proteins that are nonessential for replication within cultured fibroblasts. Nevertheless, inactivation of some US12 family members affects virus replication in other cell types; e.g., deletion of US16 or US18 abrogates virus growth in endothelial and epithelial cells or in human gingival tissue, respectively, suggesting a role for some US12 proteins in HCMV cell tropism. Here, we provide evidence that another member, US20, impacts the ability of a clinical strain of HCMV to replicate in endothelial cells. Through the use of recombinant HCMV encoding tagged versions of the US20 protein, we investigated the expression pattern, localization, and topology of the US20-encoded protein (pUS20). We show that pUS20 is expressed as a partially glycosylated 7TMD protein which accumulates late in infection in endoplasmic reticulum-derived peripheral structures localized outside the cytoplasmic virus assembly compartment (cVAC). US20-deficient mutants generated in the TR clinical strain of HCMV exhibited major growth defects in different types of endothelial cells, whereas they replicated normally in fibroblasts and epithelial cells. While the attachment and entry phases in endothelial cells were not significantly affected by the absence of US20 protein, US20-null viruses failed to replicate viral DNA and express representative E and L mRNAs and proteins. Taken together, these results indicate that US20 sustains the HCMV replication cycle at a stage subsequent to entry but prior to E gene expression and viral DNA synthesis in endothelial cells. IMPORTANCE Human cytomegalovirus (HCMV) is a major pathogen in newborns and immunocompromised individuals. A hallmark of HCMV pathogenesis is its ability to productively replicate in an exceptionally broad range of target cells, including endothelial cells, which represent

  15. Hepatocyte growth factor protects human endothelial cells against advanced glycation end products-induced apoposis

    SciTech Connect

    Zhou Yijun . E-mail: zhou-yijun@hotmail.com; Wang Jiahe; Zhang Jin

    2006-06-02

    Advanced glycation end products (AGEs) form by a non-enzymatic reaction between reducing sugars and biological proteins, which play an important role in the pathogenesis of atherosclerosis. In this study, we assessed AGEs effects on human umbilical vein endothelial cells (HUVECs) growth, proliferation and apoptosis. Additionally, we investigated whether hepatocyte growth factor (HGF), an anti-apoptotic factor for endothelial cells, prevents AGEs-induced apoptosis of HUVECs. HUVECs were treated with AGEs in the presence or absence of HGF. Treatment of HUVECs with AGEs changed cell morphology, decreased cell viability, and induced DNA fragmentation, leading to apoptosis. Apoptosis was induced by AGEs in a dose- and time-dependent fashion. AGEs markedly elevated Bax and decreased NF-{kappa}B, but not Bcl-2 expression. Additionally, AGEs significantly inhibited cell growth through a pro-apoptotic action involving caspase-3 and -9 activations in HUVECs. Most importantly, pretreatment with HGF protected against AGEs-induced cytotoxicity in the endothelial cells. HGF significantly promoted the expression of Bcl-2 and NF-{kappa}B, while decreasing the activities of caspase-3 and -9 without affecting Bax level. Our data suggest that AGEs induce apoptosis in endothelial cells. HGF effectively attenuate AGEs-induced endothelial cell apoptosis. These findings provide new perspectives in the role of HGF in cardiovascular disease.

  16. Application of multiple levels of fluid shear stress to endothelial cells plated on polyacrylamide gels†

    PubMed Central

    Galie, P. A.; van Oosten, A.; Chen, C. S.

    2015-01-01

    Measurements of endothelial cell response to fluid shear stress have previously been performed on unphysiologically rigid substrates. We describe the design and implementation of a microfluidic device that applies discrete levels of shear stress to cells plated on hydrogel-based substrates of physiologicallyrelevant stiffness. The setup allows for measurements of cell morphology and inflammatory response to the combined stimuli, and identifies mechanisms by which vascular stiffening leads to pathological responses to blood flow. We found that the magnitude of shear stress required to affect endothelial cell morphology and inflammatory response depended on substrate stiffness. Endothelial cells on 100 Pa substrates demonstrate a greater increase in cell area and cortical stiffness and decrease in NF-κB nuclear translocation in response to TNF-α treatment compared to controls than cells plated on 10 kPa substrates. The response of endothelial cells on soft substrates to shear stress depends on the presence of hyaluronan (HA). These results emphasize the importance of substrate stiffness on endothelial function, and elucidate a means by which vascular stiffening in aging and disease can impact the endothelium. PMID:25573790

  17. 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

  18. SIRT1 reduces endothelial activation without affecting vascular function in ApoE-/- mice

    PubMed Central

    Stein, Sokrates; Schäfer, Nicola; Breitenstein, Alexander; Besler, Christian; Winnik, Stephan; Lohmann, Christine; Heinrich, Kathrin; Brokopp, Chad E.; Handschin, Christoph; Landmesser, Ulf; Tanner, Felix C.; Lüscher, Thomas F.; Matter, Christian M.

    2010-01-01

    Excessive production of reactive oxygen species (ROS) contributes to progression of atherosclerosis, at least in part by causing endothelial dysfunction and inflammatory activation. The class III histone deacetylase SIRT1 has been implicated in extension of lifespan. In the vasculature,SIRT1 gain-of-function using SIRT1 overexpression or activation has been shown to improve endothelial function in mice and rats via stimulation of endothelial nitric oxide (NO) synthase (eNOS). However, the effects of SIRT1 loss-of-function on the endothelium in atherosclerosis remain to be characterized. Thus, we have investigated the endothelial effects of decreased endogenous SIRT1 in hypercholesterolemic ApoE-/- mice. We observed no difference in endothelial relaxation and eNOS (Ser1177) phosphorylation between 20-week old male atherosclerotic ApoE-/- SIRT1+/- and ApoE-/- SIRT1+/+ mice. However, SIRT1 prevented endothelial superoxide production, inhibited NF-κB signaling, and diminished expression of adhesion molecules. Treatment of young hypercholesterolemic ApoE-/- SIRT1+/- mice with lipopolysaccharide to boost NF-κB signaling led to a more pronounced endothelial expression of ICAM-1 and VCAM-1 as compared to ApoE-/- SIRT1+/+ mice. In conclusion, endogenous SIRT1 diminishes endothelial activation in ApoE-/- mice, but does not affect endothelium-dependent vasodilatation. PMID:20606253

  19. 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

  20. 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

  1. 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

  2. Response of endothelial cells to decellularized extracellular matrix deposited by bone marrow mesenchymal stem cells

    PubMed Central

    Xu, Yue; Yan, Mengdie; Gong, Yihong; Chen, Lei; Zhao, Feng; Zhang, Zhaoqiang

    2014-01-01

    Objective: Evaluate the behavior and function of human umbilical vein endothelial cells (HUVECs) on decellularized extracellular matrix (ECM) deposited by bone marrow mesenchymal stem cells (BMSCs). Methods: Prepared through chemical approach, decellularized ECM was characterized by use of immunofluorescence staining. The morphology, attachment, proliferation and migration of HUVECs cultured on six-well tissue culture plastic (TCP) and decellularized ECM were investigated. Results: Decellularized ECM was successfully prepared without three-dimensional architecture disruption. This biological scaffold is similar to nature vascular ECM, preserved various matrix proteins such as type I collagen, type III collagen and fibronection. HUVECs on decellularized ECM showed well attachment and regular arrangement. Decellularized ECM could also significantly enhance the migration and proliferation potential of HUVECs in contrast to TCP. Conclusion: Deposited by BMSCs, ECM can affect the behavior of endothelial cell and could be used as a promising material in tissue engineering. PMID:25663998

  3. 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.

  4. Oxidative stress modulates nucleobase transport in microvascular endothelial cells.

    PubMed

    Bone, Derek B J; Antic, Milica; Vilas, Gonzalo; Hammond, James R

    2014-09-01

    Purine nucleosides and nucleobases play key roles in the physiological response to vascular ischemia/reperfusion events. The intra- and extracellular concentrations of these compounds are controlled, in part, by equilibrative nucleoside transporter subtype 1 (ENT1; SLC29A1) and by equilibrative nucleobase transporter subtype 1 (ENBT1). These transporters are expressed at the membranes of numerous cell types including microvascular endothelial cells. We studied the impact of reactive oxygen species on the function of ENT1 and ENBT1 in primary (CMVEC) and immortalized (HMEC-1) human microvascular endothelial cells. Both cell types displayed similar transporter expression profiles, with the majority (>90%) of 2-chloro[(3)H]adenosine (nucleoside) uptake mediated by ENT1 and [(3)H]hypoxanthine (nucleobase) uptake mediated by ENBT1. An in vitro mineral oil-overlay model of ischemia/reperfusion had no effect on ENT1 function, but significantly reduced ENBT1 Vmax in both cell types. This decrease in transport function was mimicked by the intracellular superoxide generator menadione and could be reversed by the superoxide dismutase mimetic MnTMPyP. In contrast, neither the extracellular peroxide donor TBHP nor the extracellular peroxynitrite donor 3-morpholinosydnonimine (SIN-1) affected ENBT1-mediated [(3)H]hypoxanthine uptake. SIN-1 did, however, enhance ENT1-mediated 2-chloro[(3)H]adenosine uptake. Our data establish HMEC-1 as an appropriate model for study of purine transport in CMVEC. Additionally, these data suggest that the generation of intracellular superoxide in ischemia/reperfusion leads to the down-regulation of ENBT1 function. Modification of purine transport by oxidant stress may contribute to ischemia/reperfusion induced vascular damage and should be considered in the development of therapeutic strategies. PMID:24976360

  5. 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

  6. 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

  7. The effect of bisphosphonates on the endothelial differentiation of mesenchymal stem cells.

    PubMed

    Sharma, Dileep; Hamlet, Stephen Mark; Petcu, Eugen Bogdan; Ivanovski, Saso

    2016-01-01

    The contribution of the local stem cell niche to providing an adequate vascular framework during healing cannot be overemphasized. Bisphosphonates (BPs) are known to have a direct effect on the local vasculature, but their effect on progenitor cell differentiation is unknown. This in vitro study evaluated the effect(s) of various BPs on the differentiation of human placental mesenchymal stem cells (pMSCs) along the endothelial lineage and their subsequent functional and morphogenic capabilities. pMSC multipotency was confirmed by successful differentiation into cells of both the osteogenic and endothelial lineages, as demonstrated by positive Alizarin Red S staining and Ac-LDL uptake. pMSC differentiation in the presence of non-cytotoxic BP concentrations showed that nitrogen containing BPs had a significant inhibitory effect on cell migration and endothelial marker gene expression, as well as compromised endothelial differentiation as demonstrated using von Willebrand factor immunofluorescence staining and tube formation assay. This in vitro study demonstrated that at non-cytotoxic levels, nitrogen-containing BPs inhibit differentiation of pMSCs into cells of an endothelial lineage and affect the downstream functional capability of these cells supporting a multi-modal effect of BPs on angiogenesis as pathogenic mechanism contributing to bone healing disorders such as bisphosphonate related osteonecrosis of the jaws (BRONJ). PMID:26857282

  8. The effect of bisphosphonates on the endothelial differentiation of mesenchymal stem cells

    PubMed Central

    Sharma, Dileep; Hamlet, Stephen Mark; Petcu, Eugen Bogdan; Ivanovski, Saso

    2016-01-01

    The contribution of the local stem cell niche to providing an adequate vascular framework during healing cannot be overemphasized. Bisphosphonates (BPs) are known to have a direct effect on the local vasculature, but their effect on progenitor cell differentiation is unknown. This in vitro study evaluated the effect(s) of various BPs on the differentiation of human placental mesenchymal stem cells (pMSCs) along the endothelial lineage and their subsequent functional and morphogenic capabilities. pMSC multipotency was confirmed by successful differentiation into cells of both the osteogenic and endothelial lineages, as demonstrated by positive Alizarin Red S staining and Ac-LDL uptake. pMSC differentiation in the presence of non-cytotoxic BP concentrations showed that nitrogen containing BPs had a significant inhibitory effect on cell migration and endothelial marker gene expression, as well as compromised endothelial differentiation as demonstrated using von Willebrand factor immunofluorescence staining and tube formation assay. This in vitro study demonstrated that at non-cytotoxic levels, nitrogen-containing BPs inhibit differentiation of pMSCs into cells of an endothelial lineage and affect the downstream functional capability of these cells supporting a multi-modal effect of BPs on angiogenesis as pathogenic mechanism contributing to bone healing disorders such as bisphosphonate related osteonecrosis of the jaws (BRONJ). PMID:26857282

  9. 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.

  10. 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

  11. 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

  12. 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

  13. 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

  14. Endothelial Progenitor Cells in Diabetic Microvascular Complications: Friends or Foes?

    PubMed Central

    Yu, Cai-Guo; Zhang, Ning; Yuan, Sha-Sha; Ma, Yan; Yang, Long-Yan; Feng, Ying-Mei; Zhao, Dong

    2016-01-01

    Despite being featured as metabolic disorder, diabetic patients are largely affected by hyperglycemia-induced vascular abnormality. Accumulated evidence has confirmed the beneficial effect of endothelial progenitor cells (EPCs) in coronary heart disease. However, antivascular endothelial growth factor (anti-VEGF) treatment is the main therapy for diabetic retinopathy and nephropathy, indicating the uncertain role of EPCs in the pathogenesis of diabetic microvascular disease. In this review, we first illustrate how hyperglycemia induces metabolic and epigenetic changes in EPCs, which exerts deleterious impact on their number and function. We then discuss how abnormal angiogenesis develops in eyes and kidneys under diabetes condition, focusing on “VEGF uncoupling with nitric oxide” and “competitive angiopoietin 1/angiopoietin 2” mechanisms that are shared in both organs. Next, we dissect the nature of EPCs in diabetic microvascular complications. After we overview the current EPCs-related strategies, we point out new EPCs-associated options for future exploration. Ultimately, we hope that this review would uncover the mysterious nature of EPCs in diabetic microvascular disease for therapeutics. PMID:27313624

  15. Endothelial Progenitor Cells in Diabetic Microvascular Complications: Friends or Foes?

    PubMed

    Yu, Cai-Guo; Zhang, Ning; Yuan, Sha-Sha; Ma, Yan; Yang, Long-Yan; Feng, Ying-Mei; Zhao, Dong

    2016-01-01

    Despite being featured as metabolic disorder, diabetic patients are largely affected by hyperglycemia-induced vascular abnormality. Accumulated evidence has confirmed the beneficial effect of endothelial progenitor cells (EPCs) in coronary heart disease. However, antivascular endothelial growth factor (anti-VEGF) treatment is the main therapy for diabetic retinopathy and nephropathy, indicating the uncertain role of EPCs in the pathogenesis of diabetic microvascular disease. In this review, we first illustrate how hyperglycemia induces metabolic and epigenetic changes in EPCs, which exerts deleterious impact on their number and function. We then discuss how abnormal angiogenesis develops in eyes and kidneys under diabetes condition, focusing on "VEGF uncoupling with nitric oxide" and "competitive angiopoietin 1/angiopoietin 2" mechanisms that are shared in both organs. Next, we dissect the nature of EPCs in diabetic microvascular complications. After we overview the current EPCs-related strategies, we point out new EPCs-associated options for future exploration. Ultimately, we hope that this review would uncover the mysterious nature of EPCs in diabetic microvascular disease for therapeutics. PMID:27313624

  16. Effects of simulated microgravity on cell cycle in human endothelial cells

    NASA Astrophysics Data System (ADS)

    Sokolovskaya, Alisa A.; Ignashkova, Tatiana I.; Bochenkova, Anna V.; Moskovtsev, Aleksey A.; Baranov, Victor M.; Kubatiev, Aslan A.

    2014-06-01

    The aim of the current study is to investigate effects of simulated microgravity on the cell cycle of endothelial cells. We analyze changes in the cell cycle after exposure of endothelial-like EA.hy 926 cells to simulated microgravity using a Desktop random positioning machine (RPM). Cell cycle profiles determined by flow cytometry show, that the percentage of the cells in the G0/G1 phase after 24 and 96 h of RPM-simulated microgravity is significantly increased as compared to the control group. However, no significant difference is observed after 120 h of RPM-simulated microgravity. In regard to S phase, the percentage of cells is significantly decreased after 24 and 96 h of RPM, respectively; whereas 120 h later, the number of S-phase cells is comparable to the control group. Thus, we show that simulated microgravity inhibits cell cycle progression of human EA.hy 926 cells from the G0/G1 phase to the S phase. We observe an effect of a hibernation-like state, when the growth of the cells in the RPM group slows down, but does not stop. Our results further show that simulated microgravity can affect adhesion of endothelial cells, and alpha-tubulin expression, as most cells begin to detach from the surface of OptiCell unit after 24 h, form aggregates after 48 h, and exhibit accumulation of alpha-tubulin around the nucleus after 48 h of exposure to simulated microgravity conditions. Our results demonstrate a chance in the cell cycle in a low gravitational field.

  17. The Acute Exposure Effects of Inhaled Nickel Nanoparticles on Murine Endothelial Progenitor Cells

    PubMed Central

    Liberda, Eric N; Cuevas, Azita K; Qu, Qingshan; Chen, Lung Chi

    2014-01-01

    Introduction The discovery of endothelial progenitor cells (EPCs) may help to explain observed cardiovascular effects associated with inhaled nickel nanoparticle exposures such as increases in vascular inflammation, generate reactive oxygen species, alter vasomotor tone, and potentiated atherosclerosis in murine species. Methods Following an acute whole body inhalation exposure to 500μg/m3 of nickel nanoparticles for 5 hrs, bone marrow EPCs from C57BL/6 mice were isolated. EPCs were harvested for their RNA or used in a variety of assays including chemotaxis, tube formation, and proliferation. Gene expression was assessed for important receptors involved in EPC mobilization and homing using RT-PCR methods. EPCs, circulating endothelial progenitor cells (CEPCs), circulating endothelial cells (CECs), and endothelial microparticles (EMPs) were quantified on a BD FACSCalibur to examine endothelial damage and repair associated with the exposure. Results and Conclusions Acute exposure to inhaled nickel nanoparticles significantly increased both bone marrow EPCs as well as their levels in circulation (CEPCs). CECs were significantly elevated indicating that endothelial damage occurred due to the exposure. There was no significant difference in EMPs between the two groups. Tube formation and chemotaxis, but not proliferation, of bone marrow EPCs was impaired in the nickel nanoparticle exposed group. These results coincided with a decrease in the mRNA of receptors involved in EPC mobilization and homing. This data provides new insight into how an acute nickel nanoparticle exposure to half of the current Occupational Safety & Health Administration permissible exposure limit may adversely affect EPCs. PMID:25144474

  18. Methamphetamine is not Toxic but Disrupts the Cell Cycle of Blood-Brain Barrier Endothelial Cells.

    PubMed

    Fisher, D; Gamieldien, K; Mafunda, P S

    2015-07-01

    The cytotoxic effects of methamphetamine (MA) are well established to be caused via induced oxidative stress which in turn compromises the core function of the blood-brain barrier (BBB) by reducing its ability to regulate the homeostatic environment of the brain. While most studies were conducted over a period of 24-48 h, this study investigated the mechanisms by which chronic exposure of MA adversely affect the endothelial cells of BBB over an extended period of 96 h. MA induced significant depression of cell numbers at 96 h. This result was supported by flow cytometric data on the cell cycle which showed that brain endothelial cells (bEnd5) at 96 h were significantly suppressed in the S-phase of the cell cycle. In contrast, at 24-72 h control cell numbers for G1, S and G2-M phases were similar to MA-exposed cells. MA (0-1,000 µM) did not, however, statistically affect the viability and cytotoxicity of the bEnd5 cells, and the profile of ATP production and DNA synthesis (BrdU) across 96 h did not provide a rationale for the suppression of cell division. Our study reports for the first time that chronic exposure to MA results in long-term disruption of the cell cycle phases which eventuates in the attenuation of brain capillary endothelial cell growth after 96 h, compounding and contributing to the already well-known adverse short-term permeability effects of MA exposure on the BBB. PMID:25666340

  19. 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

  20. 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

  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. 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

  3. 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

  4. 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

  5. Human umbilical cord blood mononuclear cells activate the survival protein Akt in cardiac myocytes and endothelial cells that limits apoptosis and necrosis during hypoxia.

    PubMed

    Henning, Robert J; Dennis, Steve; Sawmiller, Darrell; Hunter, Lorynn; Sanberg, Paul; Miller, Leslie

    2012-06-01

    We have previously reported that human umbilical cord blood mononuclear cells (HUCBC), which contain hematopoietic, mesenchymal, and endothelial stem cells, can significantly reduce acute myocardial infarction size. To determine the mechanism whereby HUCBC increase myocyte and vascular endothelial cell survival, we treated cardiac myocytes and coronary artery endothelial cells in separate experiments with HUCBC plus culture media or culture media alone and subjected the cells to 24 h of hypoxia or normoxia. We then determined in myocytes and endothelial cells activation of the cell survival protein Akt by Western blots. We also determined in these cells apoptosis by annexin V staining and necrosis by propidium iodide staining. Thereafter, we inhibited with API, a specific and sensitive Akt inhibitor, Akt activation in myocytes and endothelial cells cultured with HUCBC during hypoxia and determined cell apoptosis and necrosis. In cells cultured without HUCBC, hypoxia only slightly activated Akt. Moreover, hypoxia increased myocyte apoptosis by ≥ 226% and necrosis by 58% in comparison with myocytes in normoxia. Hypoxic treatment of endothelial cells without HUCBC increased apoptosis by 94% and necrosis by 59%. In contrast, hypoxia did not significantly affect HUCBC. Moreover, in myocyte + HUCBC cultures in hypoxia, HUCBC induced a ≥ 135% increase in myocyte phospho-Akt. Akt activation decreased myocyte apoptosis by 76% and necrosis by 35%. In endothelial cells, HUCBC increased phospho-Akt by 116%. HUCBC also decreased endothelial cell apoptosis by 58% and necrosis by 42%. Inhibition of Akt with API in myocytes and endothelial cells cultured with HUCBC during hypoxia nearly totally prevented the HUCBC-induced decrease in apoptosis and necrosis. We conclude that HUCBC can significantly decrease hypoxia-induced myocyte and endothelial cell apoptosis and necrosis by activating Akt in these cells and in this manner HUCBC can limit myocardial ischemia and injury. PMID

  6. Estrogen Stimulates Homing of Endothelial Progenitor Cells to Endometriotic Lesions.

    PubMed

    Rudzitis-Auth, Jeannette; Nenicu, Anca; Nickels, Ruth M; Menger, Michael D; Laschke, Matthias W

    2016-08-01

    The incorporation of endothelial progenitor cells (EPCs) into microvessels contributes to the vascularization of endometriotic lesions. Herein, we analyzed whether this vasculogenic process is regulated by estrogen. Estrogen- and vehicle-treated human EPCs were analyzed for migration and tube formation. Endometriotic lesions were induced in irradiated FVB/N mice, which were reconstituted with bone marrow from FVB/N-TgN (Tie2/green fluorescent protein) 287 Sato mice. The animals were treated with 100 μg/kg β-estradiol 17-valerate or vehicle (control) over 7 and 28 days. Lesion growth, cyst formation, homing of green fluorescent protein(+)/Tie2(+) EPCs, vascularization, cell proliferation, and apoptosis were analyzed by high-resolution ultrasonography, caliper measurements, histology, and immunohistochemistry. Numbers of blood circulating EPCs were assessed by flow cytometry. In vitro, estrogen-treated EPCs exhibited a higher migratory and tube-forming capacity when compared with controls. In vivo, numbers of circulating EPCs were not affected by estrogen. However, estrogen significantly increased the number of EPCs incorporated into the lesions' microvasculature, resulting in an improved early vascularization. Estrogen further stimulated the growth of lesions, which exhibited massively dilated glands with a flattened layer of stroma. This was mainly because of an increased glandular secretory activity, whereas cell proliferation and apoptosis were not markedly affected. These findings indicate that vasculogenesis in endometriotic lesions is dependent on estrogen, which adds a novel hormonally regulated mechanism to the complex pathophysiology of endometriosis. PMID:27315780

  7. 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

  8. 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

  9. 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

  10. 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

  11. Sub-micron lateral topography affects endothelial migration by modulation of focal adhesion dynamics.

    PubMed

    Antonini, S; Meucci, S; Jacchetti, E; Klingauf, M; Beltram, F; Poulikakos, D; Cecchini, M; Ferrari, A

    2015-06-01

    Through the interaction with topographical features, endothelial cells tune their ability to populate target substrates, both in vivo and in vitro. Basal textures interfere with the establishment and maturation of focal adhesions (FAs) thus inducing specific cell-polarization patterns and regulating a plethora of cell activities that govern the overall endothelial function. In this study, we analyze the effect of topographical features on FAs in primary human endothelial cells. Reported data demonstrate a functional link between FA dynamics and cell polarization and spreading on structured substrates presenting variable lateral feature size. Our results reveal that gratings with 2 µm lateral periodicity maximize contact guidance. The effect is linked to the dynamical state of FAs. We argue that these results are readily applicable to the rational design of active surfaces at the interface with the blood stream. PMID:26106866

  12. 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

  13. 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

  14. 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

  15. Factors associated with graft survival and endothelial cell density after Descemet’s stripping automated endothelial keratoplasty

    PubMed Central

    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

  16. Electroporation of Brain Endothelial Cells on Chip toward Permeabilizing the Blood-Brain Barrier.

    PubMed

    Bonakdar, Mohammad; Wasson, Elisa M; Lee, Yong W; Davalos, Rafael V

    2016-01-19

    The blood-brain barrier, mainly composed of brain microvascular endothelial cells, poses an obstacle to drug delivery to the brain. Controlled permeabilization of the constituent brain endothelial cells can result in overcoming this barrier and increasing transcellular transport across it. Electroporation is a biophysical phenomenon that has shown potential in permeabilizing and overcoming this barrier. In this study we developed a microengineered in vitro model to characterize the permeabilization of adhered brain endothelial cells to large molecules in response to applied pulsed electric fields. We found the distribution of affected cells by reversible and irreversible electroporation, and quantified the uptaken amount of naturally impermeable molecules into the cells as a result of applied pulse magnitude and number of pulses. We achieved 81 ± 1.7% (N = 6) electroporated cells with 17 ± 8% (N = 5) cell death using an electric-field magnitude of ∼580 V/cm and 10 pulses. Our results provide the proper range for applied electric-field intensity and number of pulses for safe permeabilization without significantly compromising cell viability. Our results demonstrate that it is possible to permeabilize the endothelial cells of the BBB in a controlled manner, therefore lending to the feasibility of using pulsed electric fields to increase drug transport across the BBB through the transcellular pathway. PMID:26789772

  17. Microrheology and ROCK Signaling of Human Endothelial Cells Embedded in a 3D Matrix

    PubMed Central

    Panorchan, Porntula; Lee, Jerry S. H.; Kole, Thomas P.; Tseng, Yiider; Wirtz, Denis

    2006-01-01

    Cell function is profoundly affected by the geometry of the extracellular environment confining the cell. Whether and how cells plated on a two-dimensional matrix or embedded in a three-dimensional (3D) matrix mechanically sense the dimensionality of their environment is mostly unknown, partly because individual cells in an extended matrix are inaccessible to conventional cell-mechanics probes. Here we develop a functional assay based on multiple particle tracking microrheology coupled with ballistic injection of nanoparticles to measure the local intracellular micromechanical properties of individual cells embedded inside a matrix. With our novel assay, we probe the mechanical properties of the cytoplasm of individual human umbilical vein endothelial cells (HUVECs) embedded in a 3D peptide hydrogel in the presence or absence of vascular endothelial growth factor (VEGF). We found that VEGF treatment, which enhances endothelial migration, increases the compliance and reduces the elasticity of the cytoplasm of HUVECs in a matrix. This VEGF-induced softening response of the cytoplasm is abrogated by specific Rho-kinase (ROCK) inhibition. These results establish combined particle-tracking microrheology and ballistic injection as the first method able to probe the micromechanical properties and mechanical response to agonists and/or drug treatments of individual cells inside a matrix. These results suggest that ROCK plays an essential role in the regulation of the intracellular mechanical response to VEGF of endothelial cells in a 3D matrix. PMID:16891369

  18. Innovative Flow Cytometry Allows Accurate Identification of Rare Circulating Cells Involved in Endothelial Dysfunction

    PubMed Central

    Boraldi, Federica; Bartolomeo, Angelica; De Biasi, Sara; Orlando, Stefania; Costa, Sonia; Cossarizza, Andrea; Quaglino, Daniela

    2016-01-01

    Introduction Although rare, circulating endothelial and progenitor cells could be considered as markers of endothelial damage and repair potential, possibly predicting the severity of cardiovascular manifestations. A number of studies highlighted the role of these cells in age-related diseases, including those characterized by ectopic calcification. Nevertheless, their use in clinical practice is still controversial, mainly due to difficulties in finding reproducible and accurate methods for their determination. Methods Circulating mature cells (CMC, CD45-, CD34+, CD133-) and circulating progenitor cells (CPC, CD45dim, CD34bright, CD133+) were investigated by polychromatic high-speed flow cytometry to detect the expression of endothelial (CD309+) or osteogenic (BAP+) differentiation markers in healthy subjects and in patients affected by peripheral vascular manifestations associated with ectopic calcification. Results This study shows that: 1) polychromatic flow cytometry represents a valuable tool to accurately identify rare cells; 2) the balance of CD309+ on CMC/CD309+ on CPC is altered in patients affected by peripheral vascular manifestations, suggesting the occurrence of vascular damage and low repair potential; 3) the increase of circulating cells exhibiting a shift towards an osteoblast-like phenotype (BAP+) is observed in the presence of ectopic calcification. Conclusion Differences between healthy subjects and patients with ectopic calcification indicate that this approach may be useful to better evaluate endothelial dysfunction in a clinical context. PMID:27560136

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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

  8. Carbon monoxide and biliverdin prevent endothelial cell sloughing in rats with type I diabetes.

    PubMed

    Rodella, Luigi; Lamon, Brian D; Rezzani, Rita; Sangras, Bhavani; Goodman, Alvin I; Falck, John R; Abraham, Nader G

    2006-06-15

    Hyperglycemia has been linked to increased oxidative stress, a resultant endothelial cell dysfunction, and, ultimately, apoptosis. Heme oxygenases (HO-1/HO-2) and the products of their activity, biliverdin/bilirubin and carbon monoxide (CO), play a physiological role in the vascular system. The effects of heme-mediated HO-1 induction, CO, and biliverdin on urinary 8-epi-isoprostane PGF(2alpha) and endothelial cell sloughing were examined in an animal model of streptozotocin (STZ)-induced diabetes. Hyperglycemia itself did not affect HO-1 and HO-2 protein levels, but caused a net decrease in HO activity. Weekly heme administration induced HO-1 protein, as demonstrated by immunohistochemistry and Western blot analyses. Administration of biliverdin or the CO donor, CORM-3, decreased urinary 8-epi-isoprostane PGF(2alpha), P < 0.5 compared to diabetes. Hyperglycemia increased endothelial cell sloughing; 8.2 +/- 0.8 cells/ml blood in control rats vs. 48 +/- 4.8 cells/ml blood in diabetic rats (P < 0.05). Heme administration significantly increased endothelial cell sloughing in diabetic rats (98 +/- 8.1 cells/ml blood, P < 0.0007) whereas biliverdin modestly decreased endothelial cell sloughing (26 +/- 3.5 cells/ml blood, P < 0.003). Administration of CORM-3 to diabetic rats resulted in a significant decrease in endothelial cell sloughing to 21.3 +/- 2.3 (P < 0.001). Administration of SnMP to CORM-3 diabetic rats only partially reversed the protective effects of CORM-3 on endothelial cell sloughing from 21.3 +/- 2.3 to 29 +/- 2.1 cells/ml, thus confirming a direct protective of CO, in addition to the ability of CORM-3 to induce HO-1 protein. These results demonstrate that exogenously administered CO or bilirubin can prevent endothelial cell sloughing in diabetic rats, likely via a decrease in oxidative stress, and thus represents a novel approach to prophylactic vascular protection in diabetes. PMID:16785033

  9. Inhibition of Monocyte Adhesion to Brain-Derived Endothelial Cells by Dual Functional RNA Chimeras

    PubMed Central

    Hu, Jing; Xiao, Feng; Hao, Xin; Bai, Shuhua; Hao, Jiukuan

    2014-01-01

    Because adhesion of leukocytes to endothelial cells is the first step of vascular-neuronal inflammation, inhibition of adhesion and recruitment of leukocytes to vascular endothelial cells will have a beneficial effect on neuroinflammatory diseases. In this study, we used the pRNA of bacteriophage phi29 DNA packaging motor to construct a novel RNA nanoparticle for specific targeting to transferrin receptor (TfR) on the murine brain-derived endothelial cells (bEND5) to deliver ICAM-1 siRNA. This RNA nanoparticle (FRS-NPs) contained a FB4 aptamer targeting to TfR and a siRNA moiety for silencing the intercellular adhesion molecule-1 (ICAM-1). Our data indicated that this RNA nanoparticle was delivered into murine brain-derived endothelial cells. Furthermore, the siRNA was released from the FRS-NPs in the cells and knocked down ICAM-1 expression in the TNF-α–stimulated cells and in the cells under oxygen-glucose deprivation/reoxygenation (OGD/R) condition. The functional end points of the study indicated that FRS-NPs significantly inhibited monocyte adhesion to the bEND5 cells induced by TNF-α and OGD/R. In conclusion, our approach using RNA nanotechnology for siRNA delivery could be potentially applied for inhibition of inflammation in ischemic stroke and other neuroinflammatory diseases, or diseases affecting endothelium of vasculature. PMID:25368913

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. Downregulation of Fes inhibits VEGF-A-induced chemotaxis and capillary-like morphogenesis by cultured endothelial cells

    PubMed Central

    Kanda, Shigeru; Kanetake, Hiroshi; Miyata, Yasuyoshi

    2007-01-01

    Abstract The aim of this study was to determine whether the downregulation of endogenous Fes by siRNA in cultured endothelial cells affects vascular endothelial growth factor-A (VEGF-A)-induced chemotaxis and capillary-like morphogenesis, which are considered as angiogenic cellular responses in vitro. VEGF-A-treatment induced autophosphorylation of Fes in cultured endothelial cells.LY294002, a phosphoinositide 3-kinase inhibitor, significantly inhibited VEGF-A-induced chemotaxis and capillary-like morphogenesis.Downregulation of Fes attenuated these VEGF-A-induced cellular responses but LY294002 did not produce further inhibition of these responses. Downregulation of Fes neither affected VEGF-A-induced autophosphorylation of VEGF receptor 2 nor mitogen-activated protein kinase activation, but markedly decreased Akt activation.Taken together, our novel results indicate the involvement of Fes in VEGF-A-induced cellular responses by cultured endothelial cells. PMID:17521372

  19. 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

  20. 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

  1. 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.

  2. 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

  3. Estrogen-induced DNA synthesis in vascular endothelial cells is mediated by ROS signaling

    PubMed Central

    Felty, Quentin

    2006-01-01

    Background Since estrogen is known to increase vascular endothelial cell growth, elevated estrogen exposure from hormone replacement therapy or oral contraceptives has the potential to contribute in the development of abnormal proliferative vascular lesions and subsequent thickening of the vasculature. How estrogen may support or promote vascular lesions is not clear. We have examined in this study whether estrogen exposure to vascular endothelial cells increase the formation of reactive oxygen species (ROS), and estrogen-induced ROS is involved in the growth of endothelial cells. Methods The effect of estrogen on the production of intracellular oxidants and the role of estrogen-induced ROS on cell growth was studied in human umbilical vein endothelial cells. ROS were measured by monitoring the oxidation of 2'7'-dichlorofluorescin by spectrofluorometry. Endothelial cell growth was measured by a colorimetric immunoassay based on BrdU incorporation into DNA. Results Physiological concentrations of estrogen (367 fmol and 3.67 pmol) triggered a rapid 2-fold increase in intracellular oxidants in endothelial cells. E2-induced ROS formation was inhibited to basal levels by cotreatment with the mitochondrial inhibitor rotenone (2 μM) and xanthine oxidase inhibitor allopurinol (50 μM). Inhibitors of NAD(P)H oxidase, apocynin and DPI, did not block E2-induced ROS formation. Furthermore, the NOS inhibitor, L-NAME, did not prevent the increase in E2-induced ROS. These findings indicate both mitochondria and xanthine oxidase are the source of ROS in estrogen treated vascular endothelial cells. E2 treated cells showed a 2-fold induction of BrdU incorporation at 18 h which was not observed in cells exposed to vehicle alone. Cotreatment with ebselen (20 μM) and NAC (1 mM) inhibited E2-induced BrdU incorporation without affecting the basal levels of DNA synthesis. The observed inhibitory effect of NAC and ebselen on E2-induced DNA synthesis was also shown to be dose dependent

  4. 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

  5. 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

  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. Adhesion and migration of polymorphonuclear leukocytes across human brain microvessel endothelial cells are differentially regulated by endothelial cell adhesion molecules and modulate monolayer permeability.

    PubMed

    Wong, Donald; Prameya, Rukmini; Dorovini-Zis, Katerina

    2007-03-01

    The mechanisms by which polymorphonuclear leukocytes (PMN) cross the human blood-brain barrier have not been fully elucidated. Using a well characterized in vitro model of the human BBB, we examined the role of endothelial cell adhesion molecules on the adhesion and transendothelial migration of PMN across primary cultures of human brain microvessel endothelial cells (HBMEC). A small number of PMN (0.06%) adhered to unstimulated HBMEC, and the basal adhesion was not affected by anti-adhesion molecule antibodies. Treatment of HBMEC with tumor necrosis factor (TNF)-alpha resulted in increased PMN adhesion that was significantly inhibited by blocking antibodies to E-selectin and ICAM-1, but not VCAM-1 or PECAM-1. A very small number of adherent PMN migrated across unstimulated HBMEC monolayers. Migration increased 2 to 20 fold following stimulation of HBMEC with TNF-alpha. Monoclonal antibody blocking studies showed that PMN used ICAM-1, but not VCAM-1, E-selectin or PECAM-1 to move across activated monolayers. Anti-adhesion molecule antibodies did not diminish the basal PMN migration. Ultrastructurally, PMN often aggregated on top and between adjacent endothelial cells and adhered by first extending pseudopodia along the apical endothelial surface. They then flattened and inserted themselves between endothelial cells in order to migrate across the monolayers. At the end of the migration period, the cultures resumed their continuity with no evidence of disruption. Transendothelial migration of PMN decreased the transendothelial electrical resistance and increased the permeability to horseradish peroxidase, which penetrated alongside the migrating leukocytes. A blocking antibody to ICAM-1 that greatly decreased migration, had no effect on the permeability changes. These studies provide insights into the mechanisms that regulate the entry of PMN into the brain and the increased permeability of the BBB in CNS inflammation. PMID:17291598

  10. Two-chain high molecular weight kininogen induces endothelial cell apoptosis and inhibits angiogenesis: partial activity within domain 5.

    PubMed

    Zhang, J C; Claffey, K; Sakthivel, R; Darzynkiewicz, Z; Shaw, D E; Leal, J; Wang, Y C; Lu, F M; McCrae, K R

    2000-12-01

    We previously reported that the binding of two-chain high molecular weight kininogen (HKa) to endothelial cells may occur through interactions with endothelial urokinase receptors. Since the binding of urokinase to urokinase receptors activates signaling responses and may stimulate mitogenesis, we assessed the effect of HKa binding on endothelial cell proliferation. Unexpectedly, HKa inhibited proliferation in response to several growth factors, with 50% inhibition caused by approximately 10 nM HKa. This activity was Zn(2+) dependent and not shared by either single-chain high molecular weight kininogen (HK) or low molecular weight kininogen. HKa selectively inhibited the proliferation of human umbilical vein and dermal microvascular endothelial cells, but did not affect that of umbilical vein or human aortic smooth muscle cells, trophoblasts, fibroblasts, or carcinoma cells. Inhibition of endothelial proliferation by HKa was associated with endothelial cell apoptosis and unaffected by antibodies that block the binding of HK or HKa to any of their known endothelial receptors. Recombinant HK domain 5 displayed activity similar to that of HKa. In vivo, HKa inhibited neovascularization of subcutaneously implanted Matrigel plugs, as well as rat corneal angiogenesis. These results demonstrate that HKa is a novel inhibitor of angiogenesis, whose activity is dependent on the unique conformation of the two-chain molecule. PMID:11099478

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. TGF-{beta}2 inhibits AKT activation and FGF-2-induced corneal endothelial cell proliferation

    SciTech Connect

    Lu Jiawei; Lu Zhenyu; Reinach, Peter

    2006-11-01

    The corneal endothelial cells form a boundary layer between anterior chamber and cornea. This single cell layer is important to maintain cornea transparency by eliciting net fluid transport into the anterior chamber. Injuries of the corneal endothelial layer in humans lead to corneal swelling and translucence. This hindrance is thought to be due to limited proliferative capacity of the endothelial layer. Fibroblast growth factor 2 (FGF-2) and transforming growth factor-beta 2 (TGF-{beta}2) are both found in aqueous humor, and these two cytokines promote and inhibit cell growth, respectively. The intracellular signaling mechanisms by which TGF-{beta}2 suppresses the mitogenic response to FGF-2, however, remain unclear. We have addressed this question by investigating potential crosstalk between FGF-2-induced and TGF-{beta}2-regulated intracellular signaling events in cultured bovine corneal endothelial (BCE) cells. We found that TGF-{beta}2 and FGF-2 oppositely affect BCE cell proliferation and TGF-{beta}2 can override the stimulating effects of FGF-2 by increasing COX-2 expression in these cells. Consistent with these findings, overexpression of COX-2 significantly reduced FGF-2-induced cell proliferation whereas a COX-2 specific inhibitor NS398 reversed the effect of TGF-{beta}2 on FGF-2-induced cell proliferation. The COX-2 product prostaglandin E2 (PGE-2) blocks FGF-2-induced cell proliferation. Whereas FGF-2 stimulates cell proliferation by activating the AKT pathway, TGF-{beta}2 and PGE-2 both inhibit this pathway. In accordance with the effect of PGE-2, cAMP also inhibits FGF-2-induced AKT activation. These findings suggest that the mitogenic response to FGF-2 in vivo in the corneal endothelial layer may be inhibited by TGF-{beta}2-induced suppression of the PI3-kinase/AKT signaling pathway.

  16. Ghrelin stimulates angiogenesis in human microvascular endothelial cells: Implications beyond GH release

    SciTech Connect

    Li Aihua; Cheng Guangli; Zhu Genghui; Tarnawski, Andrzej S. . E-mail: atarnawski@yahoo.com

    2007-02-09

    Ghrelin, a peptide hormone isolated from the stomach, releases growth hormone and stimulates appetite. Ghrelin is also expressed in pancreas, kidneys, cardiovascular system and in endothelial cells. The precise role of ghrelin in endothelial cell functions remains unknown. We examined the expression of ghrelin and its receptor (GHSR1) mRNAs and proteins in human microvascular endothelial cells (HMVEC) and determined whether ghrelin affects in these cells proliferation, migration and in vitro angiogenesis; and whether MAPK/ERK2 signaling is important for the latter action. We found that ghrelin and GHSR1 are constitutively expressed in HMVEC. Treatment of HMVEC with exogenous ghrelin significantly increased in these cells proliferation, migration, in vitro angiogenesis and ERK2 phosphorylation. MEK/ERK2 inhibitor, PD 98059 abolished ghrelin-induced in vitro angiogenesis. This is First demonstration that ghrelin and its receptor are expressed in human microvascular endothelial cells and that ghrelin stimulates HMVEC proliferation, migration, and angiogenesis through activation of ERK2 signaling.

  17. 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

  18. 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.

  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. 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

  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. Ionizing radiation decreases capillary-like structure formation by endothelial cells in vitro.

    PubMed

    Ahmad, Mansur; Khurana, Neerja R; Jaberi, Joby E

    2007-01-01

    For successful tissue engineering in surgical radiotherapy patients, irradiated endothelial cells (EC) must form new blood vessels to nourish and build connections with the engineered segment. Therefore, it is critical to understand neovasculogenesis by irradiated EC. The objective of this study was to determine the effects of ionizing radiation on endothelial cell proliferation and capillary-like structures (CLS) formation. Human Umbilical Vein Endothelial Cells (HUVEC) were irradiated with single or fractionated doses of radiation. Proliferation was determined by counting cells. CLS morphology was analyzed from photomicrographs. A single dose of 8 Gy radiation was highly lethal to HUVEC compared to lower dosage. A single dose had more of an inhibitory effect on cell proliferation compared to the same dose delivered in a fractionated manner. CLS formation began after cells reached confluency. To form a CLS, a single cell expanded, and a number of cells rearranged around its periphery in an oval fashion (mimicking a vessel wall). The central cell later disintegrated leaving a void, mimicking the lumen. Irradiated EC can form CLS, although they are fewer and smaller compared to those by sham cells. By disrupting the peripheral cells, >or=4 Gy doses significantly reduced the number of CLS. The disruptive affect was seen more with large CLS compared to small CLS. At different doses, the shapes of CLS were not significantly different. PMID:17028041

  8. 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.

  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. The Transcription Factor MEF2C Negatively Controls Angiogenic Sprouting of Endothelial Cells Depending on Oxygen

    PubMed Central

    Sturtzel, Caterina; Testori, Julia; Schweighofer, Bernhard; Bilban, Martin; Hofer, Erhard

    2014-01-01

    The MADS box transcription factor MEF2C has been detected by us to be upregulated by the angiogenic factors VEGF-A and bFGF in endothelial cells. We have here investigated its potential role for angiogenesis. MEF2C was surprisingly found to strongly inhibit angiogenic sprouting, whereas a dominant negative mutant rather induced sprouting. The factor mainly affected migratory processes of endothelial cells, but not proliferation. In gene profiling experiments we delineated the alpha-2-macroglobulin gene to be highly upregulated by MEF2C. Further data confirmed that MEF2C in endothelial cells indeed induces alpha-2-macroglobulin mRNA as well as the secretion of alpha-2-macroglobulin and that conditioned supernatants of cells overexpressing MEF2C inhibit sprouting. Alpha-2-macroglobulin mediates, at least to a large extent, the inhibitory effects of MEF2C as is shown by knockdown of alpha-2-macroglobulin mRNA by lentiviral shRNA expression which reduces the inhibitory effect. However, under hypoxic conditions the VEGF-A/bFGF-mediated upregulation of MEF2C is reduced and the production of alpha-2-macroglobulin largely abolished. Taken together, this suggests that the MEF2C/alpha-2-macroglobulin axis functions in endothelial cells as a negative feed-back mechanism that adapts sprouting activity to the oxygen concentration thus diminishing inappropriate and excess angiogenesis. PMID:24988463

  11. 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

  12. 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

  13. 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

  14. Changes of myoid and endothelial cells in the peritubular wall during contraction of the seminiferous tubule.

    PubMed

    Losinno, Antonella D; Sorrivas, Viviana; Ezquer, Marcelo; Ezquer, Fernando; López, Luis A; Morales, Alfonsina

    2016-08-01

    The wall of the seminiferous tubule in rodents consists of an inner layer of myoid cells covered by an outer layer of endothelial cells. Myoid cells are a type of smooth muscle cell containing α-actin filaments arranged in two independent layers that contract when stimulated by endothelin-1. The irregular surface relief of the tubular wall is often considered a hallmark of contraction induced by a variety of stimuli. We examine morphological changes of the rat seminiferous tubule wall during contraction by a combination of light, confocal, transmission and scanning electron microscopy. During ET-1-induced contraction, myoid cells changed from a flat to a conical shape, but their actin filaments remained in independent layers. As a consequence of myoid cell contraction, the basement membrane became wavy, orientation of collagen fibers in the extracellular matrix was altered and the endothelial cell layer became folded. To observe the basement of the myoid cell cone, the endothelial cell monolayer was removed by collagenase digestion prior to SEM study. In contracted tubules, it is possible to distinguish cell relief: myoid cells have large folds on the external surface oriented parallel to the tubular axis, whereas endothelial cells have numerous cytoplasmic projections facing the interstitium. The myoid cell cytoskeleton is unusual in that the actin filaments are arranged in two orthogonal layers, which adopt differing shapes during contraction with myoid cells becoming cone-shaped. This arrangement impacts on other components of the seminiferous tubule wall and affects the propulsion of the tubular contents to the rete testis. PMID:26987820

  15. 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

  16. 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...

  17. 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

  18. 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

  19. 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

  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. 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

  2. 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

  3. Targeting of nitric oxide synthase to endothelial cell caveolae via palmitoylation: implications for nitric oxide signaling.

    PubMed Central

    García-Cardeña, G; Oh, P; Liu, J; Schnitzer, J E; Sessa, W C

    1996-01-01

    The membrane association of endothelial nitric oxide synthase (eNOS) plays an important role in the biosynthesis of nitric oxide (NO) in vascular endothelium. Previously, we have shown that in cultured endothelial cells and in intact blood vessels, eNOS is found primarily in the perinuclear region of the cells and in discrete regions of the plasma membrane, suggesting trafficking of the protein from the Golgi to specialized plasma membrane structures. Here, we show that eNOS is found in Triton X-100-insoluble membranes prepared from cultured bovine aortic endothelial cells and colocalizes with caveolin, a coat protein of caveolae, in cultured bovine lung microvascular endothelial cells as determined by confocal microscopy. To examine if eNOS is indeed in caveolae, we purified luminal endothelial cell plasma membranes and their caveolae directly from intact, perfused rat lungs. eNOS is found in the luminal plasma membranes and is markedly enriched in the purified caveolae. Because palmitoylation of eNOS does not significantly influence its membrane association, we next examined whether this modification can affect eNOS targeting to caveolae. Wild-type eNOS, but not the palmitoylation mutant form of the enzyme, colocalizes with caveolin on the cell surface in transfected NIH 3T3 cells, demonstrating that palmitoylation of eNOS is necessary for its targeting into caveolae. These data suggest that the subcellular targeting of eNOS to caveolae can restrict NO signaling to specific targets within a limited microenvironment at the cell surface and may influence signal transduction through caveolae. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8692835

  4. 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

  5. Role of androgen and vitamin D receptors in endothelial cells from benign and malignant human prostate

    PubMed Central

    Chung, Ivy; Montecinos, Viviana P.; Buttyan, Ralph; Johnson, Candace S.; Smith, Gary J.

    2013-01-01

    Forty years ago, Judah Folkman (Folkman. N Engl J Med 285: 1182–1186, 1971) proposed that tumor growth might be controlled by limiting formation of new blood vessels (angiogenesis) needed to supply a growing tumor with oxygen and nutrients. To this end, numerous “antiangiogenic” agents have been developed and tested for therapeutic efficacy in cancer patients, including prostate cancer (CaP) patients, with limited success. Despite the lack of clinical efficacy of lead anti-angiogenic therapeutics in CaP patients, recent published evidence continues to support the idea that prostate tumor vasculature provides a reasonable target for development of new therapeutics. Particularly relevant to antiangiogenic therapies targeted to the prostate is the observation that specific hormones can affect the survival and vascular function of prostate endothelial cells within normal and malignant prostate tissues. Here, we review the evidence demonstrating that both androgen(s) and vitamin D significantly impact the growth and survival of endothelial cells residing within prostate cancer and that systemic changes in circulating androgen or vitamin D drastically affect blood flow and vascularity of prostate tissue. Furthermore, recent evidence will be discussed about the expression of the receptors for both androgen and vitamin D in prostate endothelial cells that argues for direct effects of these hormone-activated receptors on the biology of endothelial cells. Based on this literature, we propose that prostate tumor vasculature represents an unexplored target for modulation of tumor growth. A better understanding of androgen and vitamin D effects on prostate endothelial cells will support development of more effective angiogenesis-targeting therapeutics for CaP patients. PMID:23548616

  6. 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

  7. Endothelial progenitor cells and asymmetric dimethylarginine after renal transplantation.

    PubMed

    Teplan, Vladimír; Mahrová, Andrea; Králová-Lesná, Ivana; Racek, Jaroslav; Valkovský, Ivo; Štollová, Milena

    2015-03-01

    Levels of the endogenous nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA) are elevated and endothelial progenitor cells (EPCs) decreased in patients undergoing renal transplantation (Tx) and may contribute to cardiovascular complications. In this study, we tested the hypothesis that elevated ADMA and decreased EPC can be positively influenced with regular physical exercise early after Tx. Blood samples for analysis of ADMA and EPC were obtained from randomly selected 64 patients after Tx who agreed to participate in a supervised aerobic exercise program for 6 months (group I). Samples were collected before the training began, 1 month after surgery (with stabilized renal function), and at 6 months after initiation. Sixty-two age, sex, human leukocyte antigens (HLA) typing, duration of previous dialysis, history of cardiovascular disease, and immunosupression regimen-matched transplant patients who did not exercise regularly were examined as controls (group II). There were no differences in ADMA levels and EPC count between both groups before the training program began. After 6 months of exercise, ADMA concentration in the group I decreased (3.50 ± 0.45 vs. 2.11 ± 0.35 μmol/L; P < .01) and was also lower comparing with group II (2.11 ± 0.23 vs. 3.25 ± 0.35 μmol/L; P < .01). In the same period, EPC cells increased from 2.085 ± 650 cells/mL versus 3.991 ± 560 cells/mL, P < .01 in group I; but in group II, changes were nonsignificant (P = .11). Blood lipids, HbA1c, insulin, and systolic blood pressure were also affected by the training program. Elevated ADMA level and decreased EPC count were significantly influenced by early regular exercise in patients after Tx. PMID:25576240

  8. 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.

  9. 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

  10. C-reactive protein promotes atherosclerosis by increasing LDL transcytosis across endothelial cells

    PubMed Central

    Bian, Fang; Yang, Xiaoyan; Zhou, Fan; Wu, Pin-Hui; Xing, Shasha; Xu, Gao; Li, Wenjing; Chi, Jiangyang; Ouyang, Changhan; Zhang, Yonghui; Xiong, Bin; Li, Yongsheng; Zheng, Tao; Wu, Dan; Chen, Xiaoqian; Jin, Si

    2014-01-01

    Background and Purpose The retention of plasma low-density lipoprotein (LDL) particles in subendothelial space following transcytosis across the endothelium is the initial step of atherosclerosis. Whether or not C-reactive protein (CRP) can directly affect the transcytosis of LDL is not clear. Here we have examined the effect of CRP on transcytosis of LDL across endothelial cells and have explored the underlying mechanisms. Experimental Approach Effects of CRP on transcytosis of FITC-labelled LDL were examined with human umbilical vein endothelial cells and venous rings in vitro and, in vivo, ApoE-/- mice. Laser scanning confocal microscopy, immunohistochemistry and Oil Red O staining were used to assay LDL. Key Results CRP increased transcytosis of LDL. An NADPH oxidase inhibitor, diphenylene iodonium, and the reducing agent, dithiothreitol partly or completely blocked CRP-stimulated increase of LDL transcytosis. The PKC inhibitor, bisindolylmaleimide I and the Src kinase inhibitor, PP2, blocked the trafficking of the molecules responsible for transcytosis. Confocal imaging analysis revealed that CRP stimulated LDL uptake by endothelial cells and vessel walls. In ApoE-/- mice, CRP significantly promoted early changes of atherosclerosis, which were blocked by inhibitors of transcytosis. Conclusions and Implications CRP promoted atherosclerosis by directly increasing the transcytosis of LDL across endothelial cells and increasing LDL retention in vascular walls. These actions of CRP were associated with generation of reactive oxygen species, activation of PKC and Src, and translocation of caveolar or soluble forms of the N-ethylmaleimide-sensitive factor attachment protein. PMID:24517733

  11. Klotho Prevents NFκB Translocation and Protects Endothelial Cell From Senescence Induced by Uremia.

    PubMed

    Buendía, Paula; Carracedo, Julia; Soriano, Sagrario; Madueño, Juan Antonio; Ortiz, Alberto; Martín-Malo, Alejandro; Aljama, Pedro; Ramírez, Rafael

    2015-10-01

    In patients with renal disease, uremia raises oxidative stress and senescence in endothelial cells, which can lead to endothelial dysfunction and cardiovascular disease. Klotho protein is a β-glucuronidase capable of hydrolyzing steroid β-glucuronides. This protein is recognized as an antiaging gene, that modulate both stress-induced senescence and functional response. The aim of the study was to investigate how senescence and oxidative stress induced by uremia in endothelial cells affects Klotho expression and whether intra or extracellular Klotho has effects on the response of these cells. Senescence and oxidative stress was obtained by exposure to uremic serum. Telomere length, the enzyme β-galactosidase, and oxidative stress were studied by flow cytometry. Nuclear factor kappa B activity was determined by electrophoretic mobility shift assay. The expression of Klotho decreased with the uremia and preceded the manifestations of cell aging. Levels of intracellular Klotho decreases associated to endothelial senescence, and exogenous Klotho prevents cellular senescence by inhibiting the increase in oxidative stress induced by uremia and diminished the nuclear factor kappa B-DNA binding ability. PMID:25246106

  12. Primary Phenomenon in the Network Formation of Endothelial Cells: Effect of Charge

    PubMed Central

    Arai, Shunto

    2015-01-01

    Blood vessels are essential organs that are involved in the supply of nutrients and oxygen and play an important role in regulating the body’s internal environment, including pH, body temperature, and water homeostasis. Many studies have examined the formation of networks of endothelial cells. The results of these studies have revealed that vascular endothelial growth factor (VEGF) affects the interactions of these cells and modulates the network structure. Though almost all previous simulation studies have assumed that the chemoattractant VEGF is present before network formation, vascular endothelial cells secrete VEGF only after the cells bind to the substrate. This suggests VEGF is not essential for vasculogenesis especially at the early stage. Using a simple experiment, we find chain-like structures which last quite longer than it is expected, unless the energetically stable cluster should be compact. Using a purely physical model and simulation, we find that the hydrodynamic interaction retard the compaction of clusters and that the chains are stabilized through the effects of charge. The charge at the surface of the cells affect the interparticle potential, and the resulting repulsive forces prevent the chains from folding. The ions surrounding the cells may also be involved in this process. PMID:26690133

  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. 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

  15. [Regulation of endothelial cells functions by ultrasonic supernatant of Streptococcus pyogenes].

    PubMed

    Starikova, É A; Lebedeva, A M; Burova, L A; Freĭdlin, I S

    2012-01-01

    Angiogenesis and vascular remodeling are vital components of inflammation. As an inflammation evolves, vessels expand to supply nutrients and inflammatory mediators, sustaining the accumulation of activated immune cells in the affected tissues. This study demonstrates that ultrasonic supernatant of Streptoccocus pyogenes has anti-angiogenic properties: inhibit EA.hy 926 human endothelial cells metabolism, adhesion, migration, proliferation. At the same time Streptococcal components inhibit signaling pathways that involve FAK and ERK1/2. These effects are not associated with necrosis or apoptosis in cell culture. Taking together, our results suggest that impairing angiogenic function of endothelial cells might contribute to the reduced tissue perfusion, hypoxia, and subsequent regional tissue necrosis caused by Streptococci group A. PMID:22567900

  16. 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

  17. 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

  18. Adhesion Molecule Expression in Human Endothelial Cells under Simulated Microgravity

    NASA Astrophysics Data System (ADS)

    Rudimov, E. G.; Andreeva, E. R.; Buravkova, L. B.

    2013-02-01

    High gravisensitivity of endothelium is now well recognized. Therefore, the microgravity can be one of the main factors affecting the endothelium in space flight. In this work we studied the effects of gravity vector randomization (3D-clinorotation in RPM) on the viability of endothelial cells from human umbilical vein (HUVEC) and the expression of adhesion molecules on its surface. After RPM exposure, HUVEC conditioning medium was collected for cytokines evaluation, a part of vials was used for immunocytochemistry and other one - for cytofluorimetric analysis of ICAM-I, VCAM-I, PECAM-I, E-selectin, Endoglin, VE-cadherin expression. The viability of HUVEC and constitutive expression of EC marker molecules PECAM-I and Endoglin were similar in all experimental groups both after 6 and 24 hrs of exposure. There were no differences in ICAM-I and E-selectin expression on HUVEC in 3 groups after 6 hrs of exposure. 24 hrs incubation has provoked decrease in ICAM-I and E-selectin expression. Thus, gravity vector randomization can lead to the disruption of ECs monolayer.

  19. Hyperoxia, Endothelial Progenitor Cell Mobilization, and Diabetic Wound Healing

    PubMed Central

    Liu, Zhao-Jun

    2008-01-01

    Abstract Diabetic foot disease is a major health problem, which affects 15% of the 200 million patients with diabetes worldwide. Diminished peripheral blood flow and decreased local neovascularization are critical factors that contribute to the delayed or nonhealing wounds in these patients. The correction of impaired local angiogenesis may be a key component in developing therapeutic protocols for treating chronic wounds of the lower extremity and diabetic foot ulcers. Endothelial progenitor cells (EPCs) are the key cellular effectors of postnatal neovascularization and play a central role in wound healing, but their circulating and wound-level numbers are decreased in diabetes, implicating an abnormality in EPC mobilization and homing mechanisms. The deficiency in EPC mobilization is presumably due to impairment of eNOS-NO cascade in bone marrow (BM). Hyperoxia, induced by a clinically relevant hyperbaric oxygen therapy (HBO) protocol, can significantly enhance the mobilization of EPCs from the BM into peripheral blood. However, increased circulating EPCs failed to reach to wound tissues. This is partly a result of downregulated production of SDF-1α in local wound lesions with diabetes. Administration of exogenous SDF-1α into wounds reversed the EPC homing impairment and, with hyperoxia, synergistically enhanced EPC mobilization, homing, neovascularization, and wound healing. Antioxid. Redox Signal. 10, 1869–1882. PMID:18627349

  20. Biomaterials trigger endothelial cell activation when co-incubated with human whole blood.

    PubMed

    Herklotz, Manuela; Hanke, Jasmin; Hänsel, Stefanie; Drichel, Juliane; Marx, Monique; Maitz, Manfred F; Werner, Carsten

    2016-10-01

    Endothelial cell activation resulting from biomaterial contact or biomaterial-induced blood activation may in turn also affect hemostasis and inflammatory processes in the blood. Current in vitro hemocompatibility assays typically ignore these modulating effects of the endothelium. This study describes a co-incubation system of human whole blood, biomaterial and endothelial cells (ECs) that was developed to overcome this limitation. First, human endothelial cells were characterized in terms of their expression of coagulation- and inflammation-relevant markers in response to various activators. Subsequently, their capacity to regulate hemostasis as well as complement and granulocyte activation was monitored in a hemocompatibility assay. After blood contact, quiescent ECs exhibited anticoagulant and anti-inflammatory properties. When they were co-incubated with surfaces exhibiting pro-coagulant or pro-inflammatory characteristics, the ECs down-regulated coagulation but not complement or leukocyte activation. Analysis of intracellular levels of the endothelial activation markers E-selectin and tissue factor showed that co-incubation with model surfaces and blood significantly increased the activation state of ECs. Finally, the coagulation- and inflammation-modulating properties of the ECs were tested after blood/biomaterial exposure. Pre-activation of ECs by biomaterials in the blood induced a pro-coagulant and pro-inflammatory state of the ECs, wherein the pro-coagulant response was higher for biomaterial/blood pre-activated ECs than for TNF-α-pre-activated cells. This work provides evidence that biomaterials, even without directly contacting the endothelium, affect the endothelial activation state with and have consequences for plasmatic and cellular reactions in the blood. PMID:27472163

  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. 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

  4. 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

  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. 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

  8. 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

  9. 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

  10. Low density lipoprotein uptake by an endothelial-smooth muscle cell bilayer

    SciTech Connect

    Alexander, J.J.; Miguel, R.; Graham, D. )

    1991-03-01

    To study the interaction of endothelial and smooth muscle cells, and the means by which such interaction may affect lipid permeability of the arterial wall, cell bilayers were established by use of a transwell culture system. After confluent growth of both cell types had been achieved, iodine 125 bound to low-density lipoprotein (10 ng protein/ml) was added to the media of the upper well. After a 3-hour incubation period, the iodine 125-bound low-density lipoprotein content of the upper and lower media demonstrated an impedance to lipoprotein movement across the endothelial cell monolayer as compared to the bare porous polycarbonate filter of the transwell (p less than 10(-6)). The presence of smooth muscle cells in the bottom well significantly enhanced the permeability of the endothelial cell layer (p less than 10(-60)). This effect remained unchanged over a 9-day time course. Membrane binding and cellular uptake of low-density lipoprotein by endothelial cells was not altered by smooth muscle cells, indicating that this change in permeability could not be easily attributed to changes in receptor-mediated transport or transcytosis. Membrane binding (p less than 0.02) and cellular uptake (p less than 10(-6)) of low-density lipoprotein by smooth muscle cells in the bilayer, when adjusted for counts available in the smooth muscle cell media, were both reduced in the early incubation period as compared to isolated smooth muscle cells. The disproportionate reduction in uptake as compared to binding would suggest that this was not entirely a receptor-dependent process.

  11. 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.

  12. 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

  13. Repressed Ca(2+) clearance in parthenolide-treated murine brain bEND.3 endothelial cells.

    PubMed

    Tsai, Tien-Yao; Lou, Shyh-Liang; Cheng, Ka-Shun; Wong, Kar-Lok; Wang, Mei-Ling; Su, Tzu-Hui; Chan, Paul; Leung, Yuk-Man

    2015-12-15

    Parthenolide is a sesquiterpene lactone compound isolated from the leaves and flowerheads of the plant feverfew (Tanacetum parthenium). The anticancer effects of parthenolide have been well studied and this lactone compound is currently under clinical trials. Parthenolide is also a protective agent in cardiac reperfusion injury via its inhibition of nuclear factor-κB (NF-κB). Not much is known if this compound affects signal transduction in non-tumor cells. We investigated whether parthenolide affected Ca(2+) signaling in endothelial cells, key components in regulating the vascular tone. In this work using mouse cortical microvascular bEND.3 endothelial cells, we found that a 15-h treatment with parthenolide resulted in amplified ATP-triggered Ca(2+) signal; the latter had a very slow decay rate suggesting suppression of Ca(2+) clearance. Evidence suggests parthenolide suppressed Ca(2+) clearance by inhibiting the plasmalemmal Ca(2+) pump; such suppression did not result from decreased expression of the plasmalemmal Ca(2+) pump protein. Rather, such suppression was possibly a consequence of endoplasmic reticulum (ER) stress, since salubrinal (an ER stress protector) was able to alleviate parthenolide-induced Ca(2+) clearance suppression. Given the current deployment of parthenolide as an anti-cancer drug in clinical trials and the potential usage of this lactone as a cardioprotectant, it is important to examine in details the perturbing effects of parthenolide on Ca(2+) homeostasis in endothelial cells and neighboring vascular smooth muscle cells, activities of which exert profound effects on hemodynamics. PMID:26607466

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. Inhibition of endothelial cell functions by novel potential cancer chemopreventive agents.

    PubMed

    Bertl, Elisabeth; Becker, Hans; Eicher, Theophil; Herhaus, Christian; Kapadia, Govind; Bartsch, Helmut; Gerhäuser, Clarissa

    2004-12-01

    Endothelial cells (EC) play a major role in tumor-induced neovascularization and bridge the gap between a microtumor and growth factors such as nutrients and oxygen supply required for expansion. Immortalized human microvascular endothelial cells (HMEC-1) were utilized to assess anti-endothelial effects of 10 novel potential cancer chemopreventive compounds from various sources that we have investigated previously in a human in vitro anti-angiogenic assay. These include the monoacylphloroglucinol isoaspidinol B, 1,2,5,7-tetrahydroxy-anthraquinone, peracetylated carnosic acid (PCA), isoxanthohumol, 2,2',4'-trimethoxychalcone, 3'-bromo-2,4-dimethoxychalcone as well as four synthetic derivatives of lunularic acid, a bibenzyl found in mosses [Int. J. Cancer Prev. 1 (2004) 47]. EC proliferation was inhibited with half-maximal inhibitory concentrations from 0.3 to 49.6muM, whereas EC migration was affected by most compounds at sub-micromolar concentrations. PCA and the bibenzyl derivative EC 1004 potently prevented differentiation of HMEC-1 into tubule-like structures. Overall, our data indicate that inhibition of endothelial cell function contributes to various extents to the chemopreventive or anti-angiogenic potential of these lead compounds. PMID:15522231

  1. [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

  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. 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

  4. 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

  5. Thrombospondin 2 Inhibits Microvascular Endothelial Cell Proliferation by a Caspase-independent Mechanism

    PubMed Central

    Armstrong, Lucas C.; Björkblom, Benny; Hankenson, Kurt D.; Siadak, Anthony W.; Stiles, Charlotte E.; Bornstein, Paul

    2002-01-01

    The matricellular protein thrombospondin 2 (TSP2) regulates a variety of cell–matrix interactions. A prominent feature of TSP2-null mice is increased microvascular density, particularly in connective tissues synthesized after injury. We investigated the cellular basis for the regulation of angiogenesis by TSP2 in cultures of murine and human fibroblasts and endothelial cells. Fibroblasts isolated from murine and human dermis synthesize TSP2 mRNA and secrete significant amounts of immunoreactive TSP2, whereas endothelial cells from mouse lung and human dermis did not synthesize TSP2 mRNA or protein. Recombinant mouse TSP2 inhibited growth of human microvascular endothelial cells (HMVECs) mediated by basic fibroblast growth factor, insulin-like growth factor-1, epidermal growth factor, and vascular endothelial growth factor (VEGF). HMVECs exposed to TSP2 in the presence of these growth factors had a decreased proportion of cells in S and G2/M phases. HMVECs cultured with a combination of basic fibroblast growth factor, insulin-like growth factor-1, and epidermal growth factor displayed an increased proportion of nonviable cells in the presence of TSP2, but the addition of VEGF blocked this TSP2-mediated impairment of cell viability. TSP2-mediated inhibition of DNA synthesis by HMVECs in the presence of VEGF was not affected by the broad-spectrum caspase inhibitor zVAD-fmk. Similar findings were obtained with TSP1. Taken together, these observations indicate that either TSP2 or TSP1 can inhibit HMVEC proliferation by inhibition of cell cycle progression and induction of cell death, but the mechanisms responsible for TSP2-mediated inhibition of cell cycle progression are independent from those leading to cell death. PMID:12058057

  6. 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...

  7. 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

  8. 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

  9. 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

  10. Dihydroartemisinin induces endothelial cell anoikis through the activation of the JNK signaling pathway

    PubMed Central

    Zhang, Jiao; Guo, Ling; Zhou, Xia; Dong, Fengyun; Li, Liqun; Cheng, Zuowang; Xu, Yinghua; Liang, Jiyong; Xie, Qi; Liu, Ju

    2016-01-01

    Angiogenesis is required for the growth and metastasis of solid tumors. The anti-malarial agent dihydroartemisinin (DHA) demonstrates potent anti-angiogenic activity, but the underlying molecular mechanisms are not yet fully understood. During the process of angiogenesis, endothelial cells migrating from existing capillaries may undergo programmed cell death after detaching from the extracellular matrix, a process that is defined as anchorage-dependent apoptosis or anoikis. In the present study, DHA-induced cell death was compared in human umbilical vein endothelial cells (HUVECs) cultured in suspension and attached to culture plates. In suspended HUVECs, the cell viability was decreased and apoptosis was increased with the treatment of 50 µM DHA for 5 h, while the same treatment did not affect the attached HUVECs. In addition, 50 µM DHA increased the phosphorylation of c-Jun N-terminal kinase (JNK) in suspended HUVECs, but not in attached HUVECs, for up to 5 h of treatment. The JNK inhibitor, SP600125, reversed DHA-induced cell death in suspended HUVECs, suggesting that the JNK pathway may mediate DHA-induced endothelial cell anoikis. The data from the present study indicates a novel mechanism for understanding the anti-angiogenic effects of DHA, which may be used as a component for chemotherapy. PMID:27602117

  11. Annexin A8 controls leukocyte recruitment to activated endothelial cells via cell surface delivery of CD63

    NASA Astrophysics Data System (ADS)

    Poeter, Michaela; Brandherm, Ines; Rossaint, Jan; Rosso, Gonzalo; Shahin, Victor; Skryabin, Boris V.; Zarbock, Alexander; Gerke, Volker; Rescher, Ursula

    2014-04-01

    To enable leukocyte adhesion to activated endothelium, the leukocyte receptor P-selectin is released from Weibel-Palade bodies (WPB) to the endothelial cell surface where it is stabilized by CD63. Here we report that loss of annexin A8 (anxA8) in human umbilical vein endothelial cells (HUVEC) strongly decreases cell surface presentation of CD63 and P-selectin, with a concomitant reduction in leukocyte rolling and adhesion. We confirm the compromised leukocyte adhesiveness in inflammatory-activated endothelial venules of anxA8-deficient mice. We find that WPB of anxA8-deficient HUVEC contain less CD63, and that this is caused by improper transport of CD63 from late multivesicular endosomes to WPB, with CD63 being retained in intraluminal vesicles. Consequently, reduced CD63 cell surface levels are seen following WPB exocytosis, resulting in enhanced P-selectin re-internalization. Our data support a model in which anxA8 affects leukocyte recruitment to activated endothelial cells by supplying WPB with sufficient amounts of the P-selectin regulator CD63.

  12. 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

  13. Role of endothelial cells in antihyperalgesia induced by a triptan and β-blocker.

    PubMed

    Joseph, E K; Levine, J D

    2013-03-01

    While blood vessels have long been implicated in diverse pain syndromes (e.g., migraine headache, angina pectoris, vasculitis, and Raynaud's syndrome), underlying mechanisms remain to be elucidated. Recent evidence supports a contribution of the vascular endothelium in endothelin-1-induced hyperalgesia, and its enhancement by repeated mechanical stimulation; a phenomenon referred to as stimulus-induced enhancement of (endothelin) hyperalgesia (SIEH). SIEH is thought to be mediated by release of ATP from endothelial cells, to act on P2X3 receptors on nociceptors. In the present study we evaluated the ability of another vasoactive hyperalgesic agent, epinephrine, to induce endothelial cell-dependent hyperalgesia and SIEH. We found that epinephrine also produces hyperalgesia and SIEH. Both P2X3 receptor antagonists, A317491 and octoxynol-9, which attenuate endothelial cell function, eliminated SIEH without affecting epinephrine hyperalgesia. We further evaluated the hypothesis that members of two important classes of drugs used to treat migraine headache, whose receptors are present in endothelial cells - the triptans and β blockers - have a vascular component to their anti-hyperalgesic action. For this, we tested the effect of ICI-118,551, a β₂-adrenergic receptor antagonist and sumatriptan, an agonist at 5-HT1B and 5-HT₁D receptors, on nociceptive effects of endothelin and epinephrine. ICI-118,551 inhibited endothelin SIEH, and attenuated epinephrine hyperalgesia and SIEH. Sumatriptan inhibited epinephrine SIEH and inhibited endothelin hyperalgesia and SIEH, while having no effect on epinephrine hyperalgesia or the hyperalgesia induced by a prototypical direct-acting inflammatory mediator, prostaglandin E₂. These results support the suggestion that triptans and β-blockers interact with the endothelial cell component of the blood vessel to produce anti-hyperalgesia. PMID:23262231

  14. Role of Endothelial Cells in Antihyperalgesia Induced by a Triptan and β-blocker

    PubMed Central

    Joseph, Elizabeth K.; Levine, Jon D.

    2012-01-01

    While blood vessels have long been implicated in diverse pain syndromes (e.g., migraine headache, angina pectoris, vasculitis, and Raynaud’s syndrome), underlying mechanisms remain to be elucidated. Recent evidence supports a contribution of the vascular endothelium in endothelin-1 induced hyperalgesia, and its enhancement by repeated mechanical stimulation; a phenomenon referred to as stimulus-induced enhancement of (endothelin) hyperalgesia (SIEH). SIEH is thought to be mediated by release of ATP from endothelial cells, to act on P2X3 receptors on nociceptors. In the present study we evaluated the ability of another vasoactive hyperalgesic agent, epinephrine, to induce endothelial cell dependent hyperalgesia and SIEH. We found that epinephrine also produces hyperalgesia and SIEH. Both a P2X3 receptor antagonist, A317491 and octoxynol-9, which attenuate endothelial cell function, eliminated SIEH without affecting epinephrine hyperalgesia. We further evaluated the hypothesis that members of two important classes of drugs used to treat migraine headache, whose receptors are present in endothelial cells - the triptans and beta blockers - have a vascular component to their anti-hyperalgesic action. For this, we tested the effect of ICI-118,551, a β2-adrenergic receptor antagonist and sumatriptan, an agonist at 5-HT1B and 5-HT1D receptors, on nociceptive effects of endothelin and epinephrine. ICI-118,551 inhibited endothelin SIEH, and attenuated epinephrine hyperalgesia and SIEH. Sumatriptan inhibited epinephrine SIEH and inhibited endothelin hyperalgesia and SIEH, while having no effect on epinephrine hyperalgesia or the hyperalgesia induced by a prototypical direct-acting inflammatory mediator, prostaglandin E2. These results support the suggestion that triptans and beta-blockers interact with the endothelial cell component of the blood vessel to produce anti-hyperalgesia. PMID:23262231

  15. Transplantation of vascular endothelial growth factor 165-transfected endothelial progenitor cells for the treatment of limb ischemia

    PubMed Central

    WANG, SHENG; CHEN, ZHONG; TANG, XIAOBIN; LIU, HUI; YANG, LIAO; WANG, YANYANG

    2015-01-01

    The present study aimed to investigate the effects of neovascularization in rabbits with limb ischemia transplanted with vascular endothelial growth factor (VEGF)165-transfected endothelial progenitor cells (EPC). Bone marrow mononuclear cells were isolated by gradient centrifugation, cultured in M199 culture medium and induced into EPCs using VEGF, basic fibroblast growth factor, and insulin-like growth factor-1, and subsequently identified. The EPCs were transfected with Adv-green fluorescent protein-VEGF165 and the proliferation potential of the cells was determined using an MTT assay. The protein expression levels of VEGF were measured by detecting its concentration levels in the supernatant using an ABC-ELISA assay. A rabbit hind limb ischemic model was established and randomly divided into three groups: (A) Control group, (B) EPC-transplanted group, and (C) Ad-VEGF165/EPCs-transplanted group. The effects of transplantation and the levels of recanalization were detected. Incorporation of the transplanted cells into the ischemic region was confirmed by 5-bromodeoxyuridine staining, and the levels of recanalization were measured by computer tomography ateriography and immunohistochemical staining. Bone marrow-derived EPCs were induced, cultivated, and successfully identified. The results of the present study determined the optimum transfection ratio that promoted the growth of EPCs. The EPCs were successfully transfected with VEGF165, and EPC proliferation was not affected by the transfection. The supernatant protein concentration levels of VEGF were markedly higher in the VEGF165-transfected group, as compared with those of the control group. Introduction of the transplanted cells into the ischemic region of group C occurred more efficiently, as compared with groups A and B. The recanalization capillary density in group C was significantly higher, as compared with groups A and B. VEGF gene transfection was able to improve the quality of EPCs, and the response

  16. 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

  17. 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

  18. 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

  19. 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

  20. Paradoxical effects of ethoxidine, a topoisomerase I inhibitor, in the cellular processes leading to angiogenesis on endothelial cells.

    PubMed

    Clere, Nicolas; Faure, Sébastien; Helesbeux, Jean-Jacques; Duval, Olivier; Andriantsitohaina, Ramaroson

    2011-03-01

    Angiogenesis, a critical step in tumorigenesis, is defined by different processes leading to neovascularization. Topoisomerase I (Top I) is the target for some of the most successful anticancer drugs that decrease tumor cell proliferation. Ethoxidine, a benzo[c]phenanthridines derivative, camptothecin analogue, has been identified as a potent inhibitor of Top I in various cancer cell lines. This study was aimed to investigate the impact of ethoxidine on angiogenesis and cellular processes including migration, proliferation and adhesion since these processes play an important role in tumor progression. Ethoxidine was incubated for 24 h at low (10⁻⁹ M) and high (10⁻⁵ M) concentrations on two types of human endothelial cells: EaHy.926 and human umbilical endothelial cells. Vascular endothelial growth factor (VEGF, 20 ng/ml) was used as a positive control. Ethoxidine at low concentration increased cell proliferation and migration that was associated with enhanced metalloproteinase 2 expression and activity, whereas high concentration of ethoxidine inhibited all of these effects. The two concentrations of ethoxidine did not affect endothelial cell adhesion. Low concentration of ethoxidine increased VEGF expression and endothelial nitric oxide (NO) synthase expression, NO and superoxide anion productions, whereas high concentration of ethoxidine did not induce any effect. Taken together, the present results highlight paradoxical effects of ethoxidine on angiogenesis depending on the concentration used. This study underscores that in addition to its anti-proliferative properties, ethoxidine may affect the generation of vascular network in tumorigenesis. PMID:21135154

  1. 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.

  2. 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)

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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...

  10. Histones Induce the Procoagulant Phenotype of Endothelial Cells through Tissue Factor Up-Regulation and Thrombomodulin Down-Regulation

    PubMed Central

    Kim, Ji Eun; Yoo, Hyun Ju; Gu, Ja Yoon; Kim, Hyun Kyung

    2016-01-01

    The high circulating levels of histones found in various thrombotic diseases may compromise the anticoagulant barrier of endothelial cells. We determined how histones affect endothelial procoagulant tissue factor (TF) and anticoagulant thrombomodulin (TM). Surface antigens, soluble forms, and mRNA levels of TF and TM were measured by flow cytometry, ELISA, and real-time RT-PCR, respectively. TF and TM activity were measured using procoagulant activity, thrombin generation, or chromogenic assays. Involvement of the toll-like receptor (TLR) was assessed using the neutralizing antibodies. Histones dose-dependently induced surface antigens, activity and mRNA levels of endothelial TF. Histone-treated endothelial cells significantly shortened the lag time and enhanced the endogenous thrombin potential of normal plasma, which was normalized by a TF neutralizing antibody. Histones induced phosphatidylserine and protein-disulfide isomerase expression in endothelial cells. Histones also reduced the surface antigen, activity, and mRNA levels of endothelial TM. Polysialic acid and heparin reversed the histone-induced TF up-regulation and TM down-regulation. Activated protein C did not affect the TF up-regulation, but interrupted TM down-regulation. TLR2, and TLR4 inhibitors partially blocked the TF up-regulation. Histones induced the endothelial procoagulant phenotype through TF up-regulation and TM down-regulation. The effects of histones were partly mediated by TLR2, TLR4. Strategies to inhibit the harmful effects of histones in endothelial cells may be required in order to prevent a thrombotic environment. PMID:27258428

  11. “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

  12. "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

  13. 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

  14. 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

  15. Ionizing Radiation Shifts the PAI-1/ID-1 Balance and Activates Notch Signaling in Endothelial Cells

    SciTech Connect

    Scharpfenecker, Marion; Kruse, Jacqueline; Sprong, Debbie; Russell, Nicola S.; Dijke, Peter ten; Stewart, Fiona A.

    2009-02-01

    Purpose: Transforming growth factor-{beta} (TGF-{beta}) and Notch signaling pathways are important regulators of vascular homeostasis and vessel remodeling; mutations in these pathways can lead to vascular disorders. Similar vascular phenotypes develop in the normal tissues of cancer patients as a long-term effect of radiotherapy. Irradiation most severely affects the capillaries, which become leaky and dilated and might eventually rupture. To investigate the mechanism of such capillary damage, we studied the effect of TGF-{beta} and Notch signaling in microvascular endothelial cells. Methods and Materials: Human microvascular endothelial cells were irradiated with 5 or 10 Gy and activation of TGF-{beta} and Notch signaling pathways was assessed by biochemical methods and a cell migration assay. Results: Ionizing radiation induced Smad2 phosphorylation and nuclear translocation and increased mRNA and protein expression of the activin-like kinase 5 (ALK5) target gene plasminogen activator inhibitor-1 (PAI-1). At the same time, we observed diminished Smad1/5/8 activation and downregulation of the ALK1 downstream target, inhibitor of DNA binding-1 (ID-1). We also measured an upregulation of the Notch ligand Jagged-1 and the target gene Hey1. Decreased inhibitor of DNA binding-1 levels coincided with a reduced ability of the cells to migrate. Conclusion: Ionizing radiation shifts the balance from ALK1 to ALK5 signaling and activates the Notch pathway in endothelial cells. This combination of anti-angiogenic signals contributes to reduced cell migration after irradiation.

  16. Fibroblast growth factor rescues brain endothelial cells lacking presenilin 1 from apoptotic cell death following serum starvation

    PubMed Central

    Gama Sosa, Miguel A.; De Gasperi, Rita; Hof, Patrick R.; Elder, Gregory A.

    2016-01-01

    Presenilin 1 (Psen1) is important for vascular brain development and is known to influence cellular stress responses. To understand the role of Psen1 in endothelial stress responses, we investigated the effects of serum withdrawal on wild type (wt) and Psen1−/− embryonic brain endothelial cells. Serum starvation induced apoptosis in Psen1−/− cells but did not affect wt cells. PI3K/AKT signaling was reduced in serum-starved Psen1−/− cells, and this was associated with elevated levels of phospho-p38 consistent with decreased pro-survival AKT signaling in the absence of Psen1. Fibroblast growth factor (FGF1 and FGF2), but not vascular endothelial growth factor (VEGF) rescued Psen1−/− cells from serum starvation induced apoptosis. Inhibition of FGF signaling induced apoptosis in wt cells under serum withdrawal, while blocking γ-secretase activity had no effect. In the absence of serum, FGF2 immunoreactivity was distributed diffusely in cytoplasmic and nuclear vesicles of wt and Psen1−/− cells, as levels of FGF2 in nuclear and cytosolic fractions were not significantly different. Thus, sensitivity of Psen1−/− cells to serum starvation is not due to lack of FGF synthesis but likely to effects of Psen1 on FGF release onto the cell surface and impaired activation of the PI3K/AKT survival pathway. PMID:27443835

  17. Fibroblast growth factor rescues brain endothelial cells lacking presenilin 1 from apoptotic cell death following serum starvation.

    PubMed

    Gama Sosa, Miguel A; De Gasperi, Rita; Hof, Patrick R; Elder, Gregory A

    2016-01-01

    Presenilin 1 (Psen1) is important for vascular brain development and is known to influence cellular stress responses. To understand the role of Psen1 in endothelial stress responses, we investigated the effects of serum withdrawal on wild type (wt) and Psen1-/- embryonic brain endothelial cells. Serum starvation induced apoptosis in Psen1-/- cells but did not affect wt cells. PI3K/AKT signaling was reduced in serum-starved Psen1-/- cells, and this was associated with elevated levels of phospho-p38 consistent with decreased pro-survival AKT signaling in the absence of Psen1. Fibroblast growth factor (FGF1 and FGF2), but not vascular endothelial growth factor (VEGF) rescued Psen1-/- cells from serum starvation induced apoptosis. Inhibition of FGF signaling induced apoptosis in wt cells under serum withdrawal, while blocking γ-secretase activity had no effect. In the absence of serum, FGF2 immunoreactivity was distributed diffusely in cytoplasmic and nuclear vesicles of wt and Psen1-/- cells, as levels of FGF2 in nuclear and cytosolic fractions were not significantly different. Thus, sensitivity of Psen1-/- cells to serum starvation is not due to lack of FGF synthesis but likely to effects of Psen1 on FGF release onto the cell surface and impaired activation of the PI3K/AKT survival pathway. PMID:27443835

  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, 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

    2015-08-01

    The use of human pluripotent stem cells for in vitro disease modelling 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-A or PDGF-BB resulted in the differentiation of either endothelial or vascular smooth muscle cells, respectively. Both protocols produced mature cells with efficiencies exceeding 80% within six days. On 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

  1. Titanium dioxide nanoparticles increase inflammatory responses in vascular endothelial cells

    PubMed Central

    Han, Sung Gu; Newsome, Bradley; Hennig, Bernhard

    2013-01-01

    Atherosclerosis is a chronic inflammatory disease that remains the leading cause of death in the United States. Numerous risk factors for endothelial cell inflammation and the development of atherosclerosis have been identified, including inhalation of ultrafine particles. Recently, engineered nanoparticles (NPs) such as titanium (TiO2) NPs have attracted much attention due to their wide range of applications. However, there are also great concerns surrounding potential adverse health effects in vascular systems. Although TiO2 NPs are known to induce oxidative stress and inflammation, the associated signaling pathways have not been well studied. The focus of this work, therefore, deals with examination of the cellular signaling pathways responsible for TiO2 NP-induced endothelial oxidative stress and inflammation. In this study, primary vascular endothelial cells were treated with TiO2 NPs for 2–16 h at concentrations of 0–50 µg/mL. TiO2 NP exposure increased cellular oxidative stress and DNA binding of NF-κB. Further, phosphorylation of Akt, ERK, JNK and p38 was increased in cells exposed to TiO2 NPs. TiO2 NPs also significantly increased induction of mRNA and protein levels of vascular cell adhesion molecule-1 (VCAM-1) and mRNA levels of monocyte chemoattractant protein-1 (MCP-1). Pretreatment with inhibitors for NF-κB (pyrrolidine dithiocarbamate), oxidative stress (epigallocatechin gallate and apocynin), Akt (LY294002), ERK (PD98059), JNK (SP600125) and p38 (SB203580) significantly attenuated TiO2 NP-induced MCP-1 and VCAM-1 gene expression, as well as activation of NF-κB. These data indicate that TiO2 NPs can induce endothelial inflammatory responses via redox-sensitive cellular signaling pathways. PMID:23380242

  2. Endothelial cell proliferation associated with lesions of murine systemic candidiasis.

    PubMed Central

    Ashman, R B; Papadimitriou, J M

    1994-01-01

    Neovascularization is associated with tumor growth and some inflammatory diseases but has not been reported to be induced by infectious agents. In a mouse model of systemic Candida albicans infection, extensive endothelial cell proliferation was seen in the periphery of brain abscesses and in the areas of fungal pyelonephritis in the kidney. This finding is important for an understanding of the pathogenesis of fungal infections and may contribute to an analysis of the mechanisms of angiogenesis. Images PMID:7523305

  3. Human Umbilical Vein Endothelial Cell Interaction with Fluorine-Incorporated Amorphous Carbon Films

    NASA Astrophysics Data System (ADS)

    Yoshimoto, Yukihiro; Hasebe, Terumitsu; Nagashima, So; Kamijo, Aki; Nakatani, Tatsuyuki; Yamagami, Takuji; Kitamura, Noriko; Kitagawa, Tomoya; Hotta, Atsushi; Takahashi, Koki; Suzuki, Tetsuya

    2012-09-01

    A major clinical concern in coronary intervention for cardiovascular disease is late stent thrombosis after the implantation of drug eluting stents (DES). DES widely used in clinical settings currently utilize polymer coatings, which can induce persistent arterial wall inflammation and delayed vascular healing, resulting in impaired endothelialization. We examined the viability of human umbilical vein endothelial cells (HUVECs) for fluorine-incorporated amorphous carbon (a-C:H:F) coatings, which are known to be anti-thrombogenic. a-C:H:F and a-C:H were synthesized on the tissue culture dishes using radio frequency plasma enhanced chemical vapor deposition by varying the ratio of hexafluoroethane and acetylene. HUVECs were seeded on coated dishes for 6 days. The results indicate that the a-C:H:F surface does not disturb HUVEC proliferation in 6 days of culture and is promising for stent materials that allows the preservation of endothelialization, even if the fluorine concentration of a-C:H surface affects the early adhesion of endothelial cells.

  4. 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.

  5. 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

  6. Protein Kinases Possibly Mediate Hypergravity-Induced Changes in F-Actin Expression by Endothelial Cells

    NASA Technical Reports Server (NTRS)

    Love, Felisha D.; Melhado, Caroline D.; Bosah, Francis N.; Harris-Hooker, Sandra A.; Sanford, Gary L.

    1998-01-01

    Basic cellular functions such as electrolyte concentration, cell growth rate, glucose utilization, bone formation, response to growth stimulation, and exocytosis are modified in microgravity. These studies indicate that microgravity affects a number of physiological systems and included in this are cell signaling mechanisms. Rijken and coworkers performed growth factor studies that showed PKC signaling and actin microfilament organization appears to be sensitive to microgravity, suggesting that the inhibition of signal transduction by microgravity may be related to alterations in actin microfilament organization. However, similar studies have not been done for vascular cells. Vascular endothelial cells play critical roles in providing nutrients to organ and tissues and in wound repair. The major deterrent to ground-based microgravity studies is that it is impossible to achieved true microgravity for longer than a few minutes on earth. Hence, it has not been possible to conduct prolonged microgravity studies except for two models that simulate certain aspects of microgravity. However, hypergravity is quite easily achieved. Several researchers have shown that hypergravity will increase the proliferation of several different cell lines while decreasing cell motility and slowing liver regeneration following partial hepatectomy, These studies indicate the hypergravity also alters the behavior of most cells. Several investigators have shown that hypergravity affects the activation of several protein kinases (PKs) in cells. In this study, we investigated whether hypergravity alters the expression of f-actin by bovine aortic endothelial cells (BAECs) and the role of PK's (calmodulin 11 dependent, PKA and PKC) as mediators of these effects.

  7. Early responses of vascular endothelial cells to topographic cues

    PubMed Central

    Dreier, Britta; Gasiorowski, Joshua Z.; Morgan, Joshua T.; Nealey, Paul F.; Russell, Paul

    2013-01-01

    Vascular endothelial cells in vivo are exposed to multiple biophysical cues provided by the basement membrane, a specialized extracellular matrix through which vascular endothelial cells are attached to the underlying stroma. The importance of biophysical cues has been widely reported, but the signaling pathways that mediate cellular recognition and response to these cues remain poorly understood. Anisotropic topographically patterned substrates with nano- through microscale feature dimensions were fabricated to investigate cellular responses to topographic cues. The present study focuses on early events following exposure of human umbilical vein endothelial cells (HUVECs) to these patterned substrates. In serum-free medium and on substrates without protein coating, HUVECs oriented parallel to the long axis of underlying ridges in as little as 30 min. Immunocytochemistry showed clear differences in the localization of the focal adhesion proteins Src, p130Cas, and focal adhesion kinase (FAK) in HUVECs cultured on topographically patterned surfaces and on planar surfaces, suggesting involvement of these proteins in mediating the response to topographic features. Knockdown experiments demonstrated that FAK was not necessary for HUVEC alignment in response to topographic cues, although FAK knockdown did modulate HUVEC migration. These data identify key events early in the cellular response to biophysical stimuli. PMID:23703527

  8. 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

  9. Shear-Induced Nitric Oxide Production by Endothelial Cells.

    PubMed

    Sriram, Krishna; Laughlin, Justin G; Rangamani, Padmini; Tartakovsky, Daniel M

    2016-07-12

    We present a biochemical model of the wall shear stress-induced activation of endothelial nitric oxide synthase (eNOS) in an endothelial cell. The model includes three key mechanotransducers: mechanosensing ion channels, integrins, and G protein-coupled receptors. The reaction cascade consists of two interconnected parts. The first is rapid activation of calcium, which results in formation of calcium-calmodulin complexes, followed by recruitment of eNOS from caveolae. The second is phosphorylation of eNOS by protein kinases PKC and AKT. The model also includes a negative feedback loop due to inhibition of calcium influx into the cell by cyclic guanosine monophosphate (cGMP). In this feedback, increased nitric oxide (NO) levels cause an increase in cGMP levels, so that cGMP inhibition of calcium influx can limit NO production. The model was used to predict the dynamics of NO production by an endothelial cell subjected to a step increase of wall shear stress from zero to a finite physiologically relevant value. Among several experimentally observed features, the model predicts a highly nonlinear, biphasic transient behavior of eNOS activation and NO production: a rapid initial activation due to the very rapid influx of calcium into the cytosol (occurring within 1-5 min) is followed by a sustained period of activation due to protein kinases. PMID:27410748

  10. Interaction of recombinant octameric hemoglobin with endothelial cells.

    PubMed

    Gaucher, Caroline; Domingues-Hamdi, Élisa; Prin-Mathieu, Christine; Menu, Patrick; Baudin-Creuza, Véronique

    2015-02-01

    Hemoglobin-based oxygen carriers (HBOCs) may generate oxidative stress, vasoconstriction and inflammation. To reduce these undesirable vasoactive properties, we increased hemoglobin (Hb) molecular size by genetic engineering with octameric Hb, recombinant (r) HbβG83C. We investigate the potential side effects of rHbβG83C on endothelial cells. The rHbβG83C has no impact on cell viability, and induces a huge repression of endothelial nitric oxide synthase gene transcription, a marker of vasomotion. No induction of Intermolecular-Adhesion Molecule 1 and E-selectin (inflammatory markers) transcription was seen. In the presence of rHbβG83C, the transcription of heme oxygenase-1 (oxidative stress marker) is weakly increased compared to the two other HBOCs (references) or Voluven (control). This genetically engineered octameric Hb, based on a human Hb βG83C mutant, leads to little impact at the level of endothelial cell inflammatory response and thus appears as an interesting molecule for HBOC development. PMID:25543885

  11. The Interaction between Fluid Wall Shear Stress and Solid Circumferential Strain Affects Endothelial Gene Expression

    PubMed Central

    Amaya, Ronny; Pierides, Alexis; Tarbell, John M.

    2015-01-01

    Endothelial cells lining the walls of blood vessels are exposed simultaneously to wall shear stress (WSS) and circumferential stress (CS) that can be characterized by the temporal phase angle between WSS and CS (stress phase angle – SPA). Regions of the circulation with highly asynchronous hemodynamics (SPA close to -180°) such as coronary arteries are associated with the development of pathological conditions such as atherosclerosis and intimal hyperplasia whereas more synchronous regions (SPA closer to 0°) are spared of disease. The present study evaluates endothelial cell gene expression of 42 atherosclerosis-related genes under asynchronous hemodynamics (SPA=-180 °) and synchronous hemodynamics (SPA=0 °). This study used a novel bioreactor to investigate the cellular response of bovine aortic endothelial cells (BAECS) exposed to a combination of pulsatile WSS and CS at SPA=0 or SPA=-180. Using a PCR array of 42 genes, we determined that BAECS exposed to non-reversing sinusoidal WSS (10±10 dyne/cm2) and CS (4 ± 4 %) over a 7 hour testing period displayed 17 genes that were up regulated by SPA = -180 °, most of them pro-atherogenic, including NFκB and other NFκB target genes. The up regulation of NFκB p50/p105 and p65 by SPA =-180° was confirmed by Western blots and immunofluorescence staining demonstrating the nuclear translocation of NFκB p50/p105 and p65. These data suggest that asynchronous hemodynamics (SPA=-180 °) can elicit proatherogenic responses in endothelial cells compared to synchronous hemodynamics without shear stress reversal, indicating that SPA may be an important parameter characterizing arterial susceptibility to disease. PMID:26147292

  12. The role of BMPs in endothelial cell function and dysfunction.

    PubMed

    Dyer, Laura A; Pi, Xinchun; Patterson, Cam

    2014-09-01

    The bone morphogenetic protein (BMP) family of proteins has a multitude of roles throughout the body. In embryonic development, BMPs promote endothelial specification and subsequent venous differentiation. The BMP pathway also plays important roles in the adult vascular endothelium, promoting angiogenesis and mediating shear and oxidative stress. The canonical BMP pathway functions through the Smad transcription factors; however, other intracellular signaling cascades can be activated, and receptor complexes beyond the traditional type I and type II receptors add additional layers of regulation. Dysregulated BMP signaling has been linked to vascular diseases including pulmonary hypertension and atherosclerosis. This review addresses recent advances in the roles of BMP signaling in the endothelium and how BMPs affect endothelial dysfunction and human disease. PMID:24908616

  13. Individual Rac GTPases Mediate Aspects of Prostate Cancer Cell and Bone Marrow Endothelial Cell Interactions

    PubMed Central

    Chatterjee, Moumita; Sequeira, Linda; Jenkins-Kabaila, Mashariki; Dubyk, Cara W.; Pathak, Surabhi; van Golen, Kenneth L.

    2011-01-01

    The Rho GTPases organize the actin cytoskeleton and are involved in cancer metastasis. Previously, we demonstrated that RhoC GTPase was required for PC-3 prostate cancer cell invasion. Targeted down-regulation of RhoC led to sustained activation of Rac1 GTPase and morphological, molecular and phenotypic changes reminiscent of epithelial to mesenchymal transition. We also reported that Rac1 is required for PC-3 cell diapedesis across a bone marrow endothelial cell layer. In the current study, we queried whether Rac3 and RhoG GTPases also have a role in prostate tumor cell diapedesis. Using specific siRNAs we demonstrate roles for each protein in PC-3 and C4-2 cell adhesion and diapedesis. We have shown that the chemokine CCL2 induces tumor cell diapedesis via Rac1 activation. Here we find that RhoG partially contributes to CCL2-induced tumor cell diapedesis. We also find that Rac1 GTPase mediates tight binding of prostate cancer cells to bone marrow endothelial cells and promotes retraction of endothelial cells required for tumor cell diapedesis. Finally, Rac1 leads to β1 integrin activation, suggesting a mechanism that Rac1 can mediate tight binding with endothelial cells. Together, our data suggest that Rac1 GTPase is key mediator of prostate cancer cell-bone marrow endothelial cell interactions. PMID:21776386

  14. In vitro differentiation of porcine aortic vascular precursor cells to endothelial and vascular smooth muscle cells.

    PubMed

    Zaniboni, Andrea; Bernardini, Chiara; Bertocchi, Martina; Zannoni, Augusta; Bianchi, Francesca; Avallone, Giancarlo; Mangano, Chiara; Sarli, Giuseppe; Calzà, Laura; Bacci, Maria Laura; Forni, Monica

    2015-09-01

    Recent findings suggest that progenitor and multipotent mesenchymal stromal cells (MSCs) are associated with vascular niches. Cells displaying mesenchymal properties and differentiating to whole components of a functional blood vessel, including endothelial and smooth muscle cells, can be defined as vascular stem cells (VSCs). Recently, we isolated a population of porcine aortic vascular precursor cells (pAVPCs), which have MSC- and pericyte-like properties. The aim of the present work was to investigate whether pAVPCs possess VSC-like properties and assess their differentiation potential toward endothelial and smooth muscle lineages. pAVPCs, maintained in a specific pericyte growth medium, were cultured in high-glucose DMEM + 10% FBS (long-term medium, LTM) or in human endothelial serum-free medium + 5% FBS and 50 ng/ml of hVEGF (endothelial differentiation medium, EDM). After 21 days of culture in LTM, pAVPCs showed an elongated fibroblast-like morphology, and they seem to organize in cord-like structures. qPCR analysis of smooth muscle markers [α-smooth muscle actin (α-SMA), calponin, and smooth muscle myosin (SMM) heavy chain] showed a significant increment of the transcripts, and immunofluorescence analysis confirmed the presence of α-SMA and SMM proteins. After 21 days of culture in EDM, pAVPCs displayed an endothelial cell-like morphology and revealed the upregulation of the expression of endothelial markers (CD31, vascular endothelial-cadherin, von Willebrand factor, and endothelial nitric oxide synthase) showing the CD31-typical pattern. In conclusion, pAVPCs could be defined as a VSC-like population considering that, if they are maintained in a specific pericyte medium, they express MSC markers, and they have, in addition to the classical mesenchymal trilineage differentiation potential, the capacity to differentiate in vitro toward the smooth muscle and the endothelial cell phenotypes. PMID:26135800

  15. In Vitro Expansion of Corneal Endothelial Cells on Biomimetic Substrates

    PubMed Central

    Palchesko, Rachelle N.; Lathrop, Kira L.; Funderburgh, James L.; Feinberg, Adam W.

    2015-01-01

    Corneal endothelial (CE) cells do not divide in vivo, leading to edema, corneal clouding and vision loss when the density drops below a critical level. The endothelium can be replaced by transplanting allogeneic tissue; however, access to donated tissue is limited worldwide resulting in critical need for new sources of corneal grafts. In vitro expansion of CE cells is a potential solution, but is challenging due to limited proliferation and loss of phenotype in vitro via endothelial to mesenchymal transformation (EMT) and senescence. We hypothesized that a bioengineered substrate recapitulating chemo-mechanical properties of Descemet's membrane would improve the in vitro expansion of CE cells while maintaining phenotype. Results show that bovine CE cells cultured on a polydimethylsiloxane surface with elastic modulus of 50 kPa and collagen IV coating achieved >3000-fold expansion. Cells grew in higher-density monolayers with polygonal morphology and ZO-1 localization at cell-cell junctions in contrast to control cells on polystyrene that lost these phenotypic markers coupled with increased α-smooth muscle actin expression and fibronectin fibril assembly. In total, these results demonstrate that a biomimetic substrate presenting native basement membrane ECM proteins and mechanical environment may be a key element in bioengineering functional CE layers for potential therapeutic applications. PMID:25609008

  16. Efficient Generation of Human Embryonic Stem Cell-Derived Corneal Endothelial Cells by Directed Differentiation

    PubMed Central

    McCabe, Kathryn L.; Kunzevitzky, Noelia J.; Chiswell, Brian P.; Xia, Xin; Goldberg, Jeffrey L.; Lanza, Robert

    2015-01-01

    Aim To generate human embryonic stem cell derived corneal endothelial cells (hESC-CECs) for transplantation in patients with corneal endothelial dystrophies. Materials and Methods Feeder-free hESC-CECs were generated by a directed differentiation protocol. hESC-CECs were characterized by morphology, expression of corneal endothelial markers, and microarray analysis of gene expression. Results hESC-CECs were nearly identical morphologically to primary human corneal endothelial cells, expressed Zona Occludens 1 (ZO-1) and Na+/K+ATPaseα1 (ATPA1) on the apical surface in monolayer culture, and produced the key proteins of Descemet’s membrane, Collagen VIIIα1 and VIIIα2 (COL8A1 and 8A2). Quantitative PCR analysis revealed expression of all corneal endothelial pump transcripts. hESC-CECs were 96% similar to primary human adult CECs by microarray analysis. Conclusion hESC-CECs are morphologically similar, express corneal endothelial cell markers and express a nearly identical complement of genes compared to human adult corneal endothelial cells. hESC-CECs may be a suitable alternative to donor-derived corneal endothelium. PMID:26689688

  17. WR-1065 and radioprotection of vascular endothelial cells. I. Cell proliferation, DNA synthesis and damage

    SciTech Connect

    Rubin, D.B.; Drab, E.A.; Kang, H.J.; Baumann, F.E.; Blazek, E.R.

    1996-02-01

    Normal tissue toxicity limits radiation therapy and could depend on the extent of damage to the vascular endothelium. Aminothiols such as WR-1065 [N-(2-mercaptoethyl)-1,3-diaminopropane] provide radioprotection for normal tissues, but little is known about how the aminothiols specifically affect the endothelium. Bovine aortic endothelial cells in culture were exposed to WR-1065 for 2 h before irradiation ({sup 137}Cs {gamma} rays, 1 Gy/min). Alone, WR-1065 demonstrated an antiproliferative effect that was related to dose (0.5-4 mM) and was evident by lowered counts of adherent cells 48 h after exposure. WR-1065 was clearly radioprotective when assessed by colony formation and incorporation of [{sup 3}H]thymidine. However, when the number of adherent cells was evaluated, radioprotection appeared to be slight and evident only in logarithmically growing cells. WR-1065 at 2 mM suppressed single-strand DNA breaks after 3 Gy by 22% and double-strand breaks after 9 Gy by 47%. Also in the irradiated cells, WR-1065 more than doubled the rate of progression of cells from G{sub 1} to S phase. WR-1065 pretreatment elevated cellular glutathione (GSH) content more than twofold. Although pretreatment with buthionine sulfoximine inhibited the elevation of GSH, the radioprotective impact of WR-1065 on total DNA strand breaks and colony formation was unaffected. These results suggest that WR-1065 may enable tissue recovery from irradiation by promoting the replication of endothelial cells, possibly by mechanisms independent of GSH. 46 refs., 6 figs., 2 tabs.

  18. Clinical significance of circulating blood and endothelial cell microparticles in sickle-cell disease.

    PubMed

    Kasar, Mutlu; Boğa, Can; Yeral, Mahmut; Asma, Suheyl; Kozanoglu, Ilknur; Ozdogu, Hakan

    2014-01-01

    Increased thrombocyte activation leads to a higher likelihood of coagulation in sickle-cell disease. On the other hand, chronic inflammation and endothelial cell activation promote vaso-occlusion. The effect of circulating microparticles derived from erythrocytes, monocytes, thrombocytes, and endothelial cells on the vaso-occlusive process is unclear. This study aims to analyze the relationship between sickle-cell disease and miscellaneous organ complications by defining the circulating microparticles during the steady-state and painful crisis periods in 45 patients with sickle-cell disease. Microparticle analysis was conducted using an eight-parameter flow cytometric method, using CD61 PERCP, CD142PE, CD106 FITC, CD14 APC-H7, CD235a FITC, and Annexin-V APC monoclonal antibodies. Microparticle levels of sickle-cell patients were found to be significantly higher during both painful crisis and steady-state situations compared with the control group (for all, p < 0.001). Among these microparticles, levels of erythrocyte microparticles (eMPs) were significantly higher during crisis than in the steady-state period (eMP steady state vs. painful crisis: 7.59 ± 12.24 vs. 7.59 ± 12.24, respectively; p < 0.01). Microparticles, including eMPs, were not affected by hydroxyurea treatment. Their level did not reflect the high frequency of crisis (>3 times/year). Thrombocyte microparticle levels were found to be higher in patients with nephropathia than in those without (48.05 ± 40.23 vs. 7.67 ± 6.75, respectively; p < 0.049). Circulating microparticles seem to be involved in the pathogenesis of sickle-cell disease. eMPs may help with the management of crisis. Thrombocyte microparticles might predict renal damage induced by vaso-occlusion. PMID:24254379

  19. 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

  20. Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention.

    PubMed

    Uthamaraj, Susheil; Tefft, Brandon J; Hlinomaz, Ota; Sandhu, Gurpreet S; Dragomir-Daescu, Dan

    2015-01-01

    Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. The feasibility of using magnetic forces to capture and retain endothelial outgrowth cells (EOC) labeled with super paramagnetic iron oxide nanoparticles (SPION) has been shown previously. But this technique requires the development of a mechanically functional stent from a magnetic and biocompatible material followed by in-vitro and in-vivo testing to prove rapid endothelialization. We developed a weakly ferromagnetic stent from 2205 duplex stainless steel using computer aided design (CAD) and its design was further refined using finite element analysis (FEA). The final design of the stent exhibited a principal strain below the fracture limit of the material during mechanical crimping and expansion. One hundred stents were manufactured and a subset of them was used for mechanical testing, retained magnetic field measurements, in-vitro cell capture studies, and in-vivo implantation studies. Ten stents were tested for deployment to verify if they sustained crimping and expansion cycle without failure. Another 10 stents were magnetized using a strong neodymium magnet and their retained magnetic field was measured. The stents showed that the retained magnetism was sufficient to capture SPION-labeled EOC in our in-vitro studies. SPION-labeled EOC capture and retention was verified in large animal models by implanting 1 magnetized stent and 1 non-magnetized control stent in each of 4 pigs. The stented arteries were explanted after 7 days and analyzed histologically. The weakly magnetic stents developed in this study were capable of attracting and retaining SPION-labeled endothelial cells which can promote rapid healing. PMID:26436434

  1. Directed Endothelial Progenitor Differentiation from Human Pluripotent Stem Cells Via Wnt Activation Under Defined Conditions.

    PubMed

    Bao, Xiaoping; Lian, Xiaojun; Palecek, Sean P

    2016-01-01

    Efficient derivation of endothelial cells and their progenitors from human pluripotent stem cells (hPSCs) can facilitate studies of human vascular development, disease modeling, drug discovery, and cell-based therapy. Here we provide a detailed protocol for directing hPSCs to functional endothelial cells and their progenitors in a completely defined, growth factor- and serum-free system by temporal modulation of Wnt/β-catenin signaling via small molecules. We demonstrate a 10-day, two-stage process that recapitulates endothelial cell development, in which hPSCs first differentiate to endothelial progenitors that then generate functional endothelial cells and smooth muscle cells. Methods to characterize endothelial cell identity and function are also described. PMID:27590162

  2. Overexpression of Ref-1 Inhibits Lead-induced Endothelial Cell Death via the Upregulation of Catalase

    PubMed Central

    Lee, Kwon Ho; Lee, Sang Ki; Kim, Hyo Shin; Cho, Eun Jung; Joo, Hee Kyoung; Lee, Eun Ji; Lee, Ji Young; Park, Myoung Soo; Chang, Seok Jong; Cho, Chung-Hyun; Park, Jin Bong

    2009-01-01

    The role of apurinic/apyrimidinic endonuclease1/redox factor-1 (Ref-1) on the lead (Pb)-induced cellular response was investigated in the cultured endothelial cells. Pb caused progressive cellular death in endothelial cells, which occurred in a concentration- and time-dependent manner. However, Ref-1 overexpression with AdRef-1 significantly inhibited Pb-induced cell death in the endothelial cells. Also the overexpression of Ref-1 significantly suppressed Pb-induced superoxide and hydrogen peroxide elevation in the endothelial cells. Pb exposure induced the downregulation of catalase, it was inhibited by the Ref-1 overexpression in the endothelial cells. Taken together, our data suggests that the overexpression of Ref-1 inhibited Pb-induced cell death via the upregulation of catalase in the cultured endothelial cells. PMID:20054488

  3. Expression and endocytosis of VEGF and its receptors in human colonic vascular endothelial cells.

    PubMed

    Wang, Dongfang; Lehman, Richard E; Donner, David B; Matli, Mary R; Warren, Robert S; Welton, Mark L

    2002-06-01

    Normal human colonic microvascular endothelial cells (HUCMEC) have been isolated from surgical specimens by their adherence to Ulex europaeus agglutinin bound to magnetic dynabeads that bind alpha-L-fucosyl residues on the endothelial cell membrane. Immunocytochemistry demonstrated the presence of a range of endothelial-specific markers on HUCMEC, including the von Willebrand factor, Ulex europaeus agglutinin, and platelet endothelial cell adhesion molecule-1. The growing cells form monolayers with the characteristic cobblestone morphology of endothelial cells and eventually form tube-like structures. HUCMEC produce vascular endothelial growth factor (VEGF) and express the receptors, kinase insert domain-containing receptor (KDR) and fms-like tyrosine kinase, through which VEGF mediates its actions in the endothelium. VEGF induces the tyrosine phosphorylation of KDR and a proliferative response from HUCMEC comparable to that elicited from human umbilical vein endothelial cells (HUVEC). On binding to HUCMEC or HUVEC, (125)I-labeled VEGF internalizes or dissociates to the medium. Once internalized, (125)I-labeled VEGF is degraded and no evidence of ligand recycling was observed. However, significantly less VEGF is internalized, and more is released to the medium from HUCMEC than HUVEC. Angiogenesis results from the proliferation and migration of microvascular, not large-vessel, endothelial cells. The demonstration that microvascular endothelial cells degrade less and release more VEGF to the medium than large-vessel endothelial cells identifies a mechanism permissive of the role of microvascular cells in angiogenesis. PMID:12016135

  4. Extracellular protein disulfide isomerase regulates coagulation on endothelial cells through modulation of phosphatidylserine exposure

    PubMed Central

    Popescu, Narcis I.; Lupu, Cristina

    2010-01-01

    Tissue factor (TF) is the cellular receptor for plasma protease factor VIIa (FVIIa), and the TF-FVIIa complex initiates coagulation in both hemostasis and thrombosis. Cell surface-exposed TF is mainly cryptic and requires activation to fully exhibit the procoagulant potential. Recently, the protein disulfide isomerase (PDI) has been hypothesized to regulate TF decryption through the redox switch of an exposed disulfide in TF extracellular domain. In this study, we analyzed PDI contribution to coagulation using an in vitro endothelial cell model. In this model, extracellular PDI is detected by imaging and flow cytometry. Inhibition of cell surface PDI induces a marked increase in TF procoagulant function, whereas exogenous addition of PDI inhibits TF decryption. The coagulant effects of PDI inhibition were sensitive to annexin V treatment, suggesting exposure of phosphatidylserine (PS), which was confirmed by prothrombinase assays and direct labeling. In contrast, exogenous PDI addition enhanced PS internalization. Analysis of fluorescent PS revealed that PDI affects both the apparent flippase and floppase activities on endothelial cells. In conclusion, we identified a new mechanism for PDI contribution to coagulation on endothelial cells, namely, the regulation of PS exposure, where PDI acts as a negative regulator of coagulation. PMID:20448108

  5. Effects of verteporfin-mediated photodynamic therapy on endothelial cells

    NASA Astrophysics Data System (ADS)

    Kraus, Daniel; Chen, Bin

    2015-03-01

    Photodynamic therapy (PDT) is a treatment modality in which cytotoxic reactive oxygen species are generated from oxygen and other biological molecules when a photosensitizer is activated by light. PDT has been approved for the treatment of cancers and age-related macular degeneration (AMD) due to its effectiveness in cell killing and manageable normal tissue complications. In this study, we characterized the effects of verteporfin-PDT on SVEC mouse endothelial cells and determined its underlying cell death mechanisms. We found that verteporfin was primarily localized in mitochondria and endoplasmic reticulum (ER) in SVEC cells. Light treatment of photosensitized SVEC cells induced a rapid onset of cell apoptosis. In addition to significant structural damages to mitochondria and ER, verteporfin-PDT caused substantial degradation of ER signaling molecules, suggesting ER stress. These results demonstrate that verteporfin-PDT triggered SVEC cell apoptosis by both mitochondrial and ER stress pathways. Results from this study may lead to novel therapeutic approaches to enhance PDT outcome.

  6. Label-free quantitative cell division monitoring of endothelial cells by digital holographic microscopy

    NASA Astrophysics Data System (ADS)

    Kemper, Björn; Bauwens, Andreas; Vollmer, Angelika; Ketelhut, Steffi; Langehanenberg, Patrik; Müthing, Johannes; Karch, Helge; von Bally, Gert

    2010-05-01

    Digital holographic microscopy (DHM) enables quantitative multifocus phase contrast imaging for nondestructive technical inspection and live cell analysis. Time-lapse investigations on human brain microvascular endothelial cells demonstrate the use of DHM for label-free dynamic quantitative monitoring of cell division of mother cells into daughter cells. Cytokinetic DHM analysis provides future applications in toxicology and cancer research.

  7. Endothelialization of Magnetic Graft Materials using SPION-labeled Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Newman, Brant R.; Dragomir-Daescu, Dan; Harbuzariu, Adriana; McIntosh, Malcolm; Harburn, J. Jonathan; Parakka, Anthony; Kalra, Manju; Holmes, David; Simari, Robert D.; Sandhu, Gurpreet S.

    2010-12-01

    Seeding vascular grafts with autologous endothelial cells (EC) has been shown to improve in vivo patency, but high cost and development time have prevented widespread clinical use. A technique for loading EC with superparamagnetic iron-oxide nanospheres (SPIONs) was recently described. SPION-loaded EC experience magnetic attractive forces in the presence of sufficient magnetic field gradients. Using a multi-factorial design of experiments approach, the quantity and spatial distribution of magnetizable metal particles within a poly (ether urethane) matrix were systematically varied to produce unique material specimens. Specimens were seeded with SPION-loaded ECs, and cell coverage was quantified at various post-seeding time intervals using micrographic image analysis. The effects of changing design parameters on cell capture and sustained cell viability on magnetic substrates were statistically examined. Magnetized ferrites and samarium cobalt demonstrated cell capture, though cytotoxicity prevented sustained cell growth. Cobalt chromium substrates showed effective cell capture and growth to near complete confluence for up to one month.

  8. Nitric Oxide Inhibits Hetero-adhesion of Cancer Cells to Endothelial Cells: Restraining Circulating Tumor Cells from Initiating Metastatic Cascade

    NASA Astrophysics Data System (ADS)

    Lu, Yusheng; Yu, Ting; Liang, Haiyan; Wang, Jichuang; Xie, Jingjing; Shao, Jingwei; Gao, Yu; Yu, Suhong; Chen, Shuming; Wang, Lie; Jia, Lee

    2014-03-01

    Adhesion of circulating tumor cells (CTCs) to vascular endothelial bed becomes a crucial starting point in metastatic cascade. We hypothesized that nitric oxide (NO) may prevent cancer metastasis from happening by its direct vasodilation and inhibition of cell adhesion molecules (CAMs). Here we show that S-nitrosocaptopril (CAP-NO, a typical NO donor) produced direct vasorelaxation that can be antagonized by typical NO scavenger hemoglobin and guanylate cyclase inhibitor. Cytokines significantly stimulated production of typical CAMs by the highly-purified human umbilical vein endothelial cells (HUVECs). CAP-NO inhibited expression of the stimulated CAMs (particularly VCAM-1) and the resultant hetero-adhesion of human colorectal cancer cells HT-29 to the HUVECs in a concentration-dependent manner. The same concentration of CAP-NO, however, did not significantly affect cell viability, cell cycle and mitochondrial membrane potential of HT-29, thus excluding the possibility that inhibition of the hetero-adhesion was caused by cytotoxicity by CAP-NO on HT-29. Hemoglobin reversed the inhibition of CAP-NO on both the hetero-adhesion between HT-29 and HUVECs and VCAM-1 expression. These data demonstrate that CAP-NO, by directly releasing NO, produces vasorelaxation and interferes with hetero-adhesion of cancer cells to vascular endothelium via down-regulating expression of CAMs. The study highlights the importance of NO in cancer metastatic prevention.

  9. A Comparison of Endothelial Cell Loss in Combined Cataract and MIGS (Hydrus) Procedure to Phacoemulsification Alone: 6-Month Results

    PubMed Central

    Fea, Antonio M.; Consolandi, Giulia; Pignata, Giulia; Cannizzo, Paola Maria Loredana; Lavia, Carlo; Billia, Filippo; Rolle, Teresa; Grignolo, Federico M.

    2015-01-01

    Purpose. To compare the corneal endothelial cell loss after phacoemulsification, alone or combined with microinvasive glaucoma surgery (MIGS), in nonglaucomatous versus primary open angle glaucoma (POAG) eyes affected by age-related cataract. Methods. 62 eyes of 62 patients were divided into group 1 (n = 25, affected by age-related cataract) and group 2 (n = 37, affected by age-related cataract and POAG). All patients underwent cataract surgery. Group 2 was divided into subgroups A (n = 19, cataract surgery alone) and B (n = 18, cataract surgery and MIGS). Prior to and 6 months after surgery the patients' endothelium was studied. Main outcomes were CD (cell density), SD (standard deviation), CV (coefficient of variation), and 6A (hexagonality coefficient) variations after surgeries. Results. There were no significant differences among the groups concerning preoperative endothelial parameters. The differences in CD before and after surgery were significant in all groups: 9.1% in group 1, 17.24% in group 2A, and 11.71% in group 2B. All endothelial parameters did not significantly change after surgery. Conclusions. Phacoemulsification determined a loss of endothelial cells in all groups. After surgery the change in endothelial parameters after MIGS was comparable to the ones of patients who underwent cataract surgery alone. PMID:26664740

  10. 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.

  11. Morphological restriction of human coronary artery endothelial cells substantially impacts global gene expression patterns

    PubMed Central

    Stiles, Jessica M; Pham, Robert; Rowntree, Rebecca K; Amaya, Clarissa; Battiste, James; Boucheron, Laura E; Mitchell, Dianne C; Bryan, Brad A

    2013-01-01

    Alterations in cell shape have been shown to modulate chromatin condensation and cell lineage specification; however, the mechanisms controlling these processes are largely unknown. Because endothelial cells experience cyclic mechanical changes from blood flow during normal physiological processes and disrupted mechanical changes as a result of abnormal blood flow, cell shape deformation and loss of polarization during coronary artery disease, we aimed to determine how morphological restriction affects global gene expression patterns. Human coronary artery endothelial cells (HCAECs) were cultured on spatially defined adhesive micropatterns, forcing them to conform to unique cellular morphologies differing in cellular polarization and angularity. We utilized pattern recognition algorithms and statistical analysis to validate the cytoskeletal pattern reproducibility and uniqueness of each micropattern, and performed microarray analysis on normal-shaped and micropatterned HCAECs to determine how constrained cellular morphology affects gene expression patterns. Analysis of the data revealed that forcing HCAECs to conform to geometrically-defined shapes significantly affects their global transcription patterns compared to nonrestricted shapes. Interestingly, gene expression patterns were altered in response to morphological restriction in general, although they were consistent regardless of the particular shape the cells conformed to. These data suggest that the ability of HCAECs to spread, although not necessarily their particular morphology, dictates their genomics patterns. PMID:23802622

  12. Atrial natriuretic peptide prevents cancer metastasis through vascular endothelial cells

    PubMed Central

    Nojiri, Takashi; Hosoda, Hiroshi; Tokudome, Takeshi; Miura, Koichi; Ishikane, Shin; Otani, Kentaro; Kishimoto, Ichiro; Shintani, Yasushi; Inoue, Masayoshi; Kimura, Toru; Sawabata, Noriyoshi; Minami, Masato; Nakagiri, Tomoyuki; Funaki, Soichiro; Takeuchi, Yukiyasu; Maeda, Hajime; Kidoya, Hiroyasu; Kiyonari, Hiroshi; Shioi, Go; Arai, Yuji; Hasegawa, Takeshi; Takakura, Nobuyuki; Hori, Megumi; Ohno, Yuko; Miyazato, Mikiya; Mochizuki, Naoki; Okumura, Meinoshin; Kangawa, Kenji

    2015-01-01

    Most patients suffering from cancer die of metastatic disease. Surgical removal of solid tumors is performed as an initial attempt to cure patients; however, surgery is often accompanied with trauma, which can promote early recurrence by provoking detachment of tumor cells into the blood stream or inducing systemic inflammation or both. We have previously reported that administration of atrial natriuretic peptide (ANP) during the perioperative period reduces inflammatory response and has a prophylactic effect on postoperative cardiopulmonary complications in lung cancer surgery. Here we demonstrate that cancer recurrence after curative surgery was significantly lower in ANP-treated patients than in control patients (surgery alone). ANP is known to bind specifically to NPR1 [also called guanylyl cyclase-A (GC-A) receptor]. In mouse models, we found that metastasis of GC-A–nonexpressing tumor cells (i.e., B16 mouse melanoma cells) to the lung was increased in vascular endothelium-specific GC-A knockout mice and decreased in vascular endothelium-specific GC-A transgenic mice compared with control mice. We examined the effect of ANP on tumor metastasis in mice treated with lipopolysaccharide, which mimics systemic inflammation induced by surgical stress. ANP inhibited the adhesion of cancer cells to pulmonary arterial and micro-vascular endothelial cells by suppressing the E-selectin expression that is promoted by inflammation. These results suggest that ANP prevents cancer metastasis by inhibiting the adhesion of tumor cells to inflamed endothelial cells. PMID:25775533

  13. Endothelial Cell Whole Genome Expression Analysis in a Mouse Model of Early-Onset Fuchs' Endothelial Corneal Dystrophy

    PubMed Central

    Matthaei, Mario; Hu, Jianfei; Meng, Huan; Lackner, Eva-Maria; Eberhart, Charles G.; Qian, Jiang; Hao, Haiping; Jun, Albert S.

    2013-01-01

    Purpose. To investigate the endothelial gene expression profile in a Col8a2 Q455K mutant knock-in mouse model of early-onset Fuchs' endothelial corneal dystrophy (FECD) and identify potential targets that can be correlated to human late-onset FECD. Methods. Diseased or normal endothelial phenotypes were verified in 12-month-old homozygous Col8a2Q455K/Q455K mutant and wild-type mice by clinical confocal microscopy. An endothelial whole genome expression profile was generated by microarray-based analysis. Result validation was performed by real-time PCR. Endothelial COX2 and JUN expression was further studied in human late-onset FECD compared to normal samples. Results. Microarray analysis demonstrated endothelial expression of 24,538 genes (162 up-regulated and 172 down-regulated targets) and identified affected gene ontology terms including Response to Stress, Protein Metabolic Process, Protein Folding, Regulation of Apoptosis, and Transporter Activity. Real-time PCR assessment confirmed increased Cox2 (P = 0.001) and Jun mRNA (P = 0.03) levels in Col8a2Q455K/Q455K mutant compared to wild-type mice. In human FECD samples, real-time PCR demonstrated a statistically significant increase in COX2 mRNA (P < 0.0001) and JUN mRNA (P = 0.002) and tissue microarray analysis showed increased endothelial COX2 (P = 0.02) and JUN protein (P = 0.04). Conclusions. The present study provides the first endothelial whole genome expression analysis in an animal model of FECD and represents a useful resource for future studies of the disease. In particular endothelial COX2 up-regulation warrants further investigation of its role in FECD. PMID:23449721

  14. 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.

  15. Antioxidant Effects of Sheep Whey Protein on Endothelial Cells

    PubMed Central

    Kerasioti, Efthalia; Stagos, Dimitrios; Georgatzi, Vasiliki; Bregou, Erinda; Priftis, Alexandros; Kafantaris, Ioannis; Kouretas, Dimitrios

    2016-01-01

    Excessive production of reactive oxygen species (ROS) may cause endothelial dysfunction and consequently vascular disease. In the present study, the possible protective effects of sheep whey protein (SWP) from tert-butyl hydroperoxide- (tBHP-) induced oxidative stress in endothelial cells (EA.hy926) were assessed using oxidative stress biomarkers. These oxidative stress biomarkers were glutathione (GSH) and ROS levels determined by flow cytometry. Moreover, thiobarbituric acid-reactive substances (TBARS), protein carbonyls (CARB), and oxidized glutathione (GSSG) were determined spectrophotometrically. The results showed that SWP at 0.78, 1.56, 3.12, and 6.24 mg of protein mL−1 increased GSH up to 141%, while it decreased GSSG to 46.7%, ROS to 58.5%, TBARS to 52.5%, and CARB to 49.0%. In conclusion, the present study demonstrated for the first time that SWP protected endothelial cells from oxidative stress. Thus, SWP may be used for developing food supplements or biofunctional foods to attenuate vascular disturbances associated with oxidative stress. PMID:27127549

  16. Antioxidant Effects of Sheep Whey Protein on Endothelial Cells.

    PubMed

    Kerasioti, Efthalia; Stagos, Dimitrios; Georgatzi, Vasiliki; Bregou, Erinda; Priftis, Alexandros; Kafantaris, Ioannis; Kouretas, Dimitrios

    2016-01-01

    Excessive production of reactive oxygen species (ROS) may cause endothelial dysfunction and consequently vascular disease. In the present study, the possible protective effects of sheep whey protein (SWP) from tert-butyl hydroperoxide- (tBHP-) induced oxidative stress in endothelial cells (EA.hy926) were assessed using oxidative stress biomarkers. These oxidative stress biomarkers were glutathione (GSH) and ROS levels determined by flow cytometry. Moreover, thiobarbituric acid-reactive substances (TBARS), protein carbonyls (CARB), and oxidized glutathione (GSSG) were determined spectrophotometrically. The results showed that SWP at 0.78, 1.56, 3.12, and 6.24 mg of protein mL(-1) increased GSH up to 141%, while it decreased GSSG to 46.7%, ROS to 58.5%, TBARS to 52.5%, and CARB to 49.0%. In conclusion, the present study demonstrated for the first time that SWP protected endothelial cells from oxidative stress. Thus, SWP may be used for developing food supplements or biofunctional foods to attenuate vascular disturbances associated with oxidative stress. PMID:27127549

  17. Endothelial cells in the context of brain arteriovenous malformations.

    PubMed

    Sammons, Vanessa; Davidson, Andrew; Tu, Jian; Stoodley, Marcus A

    2011-02-01

    A subset of brain arteriovenous malformations (AVM) cannot be treated using today's treatment paradigms. Novel therapies may be developed, however, as the underlying pathophysiology of these lesions becomes better understood. Endothelial cells (EC) are the subject of new biological therapies, such as radiosensitisation and vascular targeting. This work reviews the current research surrounding EC in the context of brain AVM, including both in vitro and AVM specimen analysis, with a particular focus on the effect of radiation on EC. EC are heterogeneous with no recognised common phenotype, which leads to difficulties in applying the results of the common studies using human umbilical vein endothelial cells to AVM research. Human brain EC are observed to have a high rate of proliferation and also have a reduced apoptotic response to inflammatory mediators such as transforming growth factor-beta. The angiogenic factors vascular endothelial growth factor and endothelin-1 (ET-1) are not normally produced by quiescent brain vasculature, but are produced by AVM EC. Radiation causes EC to separate and become disrupted. Leucocyte and platelet adherence is increased for several days post-irradiation due to increased E-selectin and P-selectin and intercellular adhesion molecule-1 expression. ET-1 is highly expressed in irradiated AVM EC. Radiosurgery produces local radiation-induced changes in EC, which may allow these changes to be harnessed in conjunction with other techniques such as vascular targeting. PMID:21167719

  18. Enhanced adhesion of early endothelial progenitor cells to radiation-induced senescence-like vascular endothelial cells in vitro.

    PubMed

    Sermsathanasawadi, Nuttawut; Ishii, Hideto; Igarashi, Kaori; Miura, Masahiko; Yoshida, Masayuki; Inoue, Yoshinori; Iwai, Takehisa

    2009-09-01

    The effects of ionizing radiation (IR) on tumor neovascularization are still unclear. We previously reported that vascular endothelial cells (ECs) expressing the IR-induced senescence-like (IRSL) phenotype exhibit a significant decrease in angiogenic activity in vitro. In this study, we examined the effects of the IRSL phenotype on adhesion to early endothelial progenitor cells (early EPCs). Adhesion of human peripheral blood-derived early EPCs to human umbilical vein endothelial cells (HUVECs) expressing the IRSL phenotype was evaluated by an adhesion assay under static conditions. It was revealed that the IRSL HUVECs supported significantly more adhesion of early EPCs than normal HUVECs. Expressions of ICAM-1, VCAM-1 and E-selectin were up-regulated in IRSL HUVECs. Pre-treatment of IRSL HUVECs with adhesion-blocking monoclonal antibodies against E-selectin and VCAM-1 significantly reduced early EPC adhesion to IRSL HUVECs, suggesting a potential role for the E-selectin and VCAM-1 in the adhesion between IRSL ECs and early EPCs. Therefore, the IRSL phenotype expressed in ECs may enhance neovascularization via increased homing of early EPCs. Our findings are first to implicate the complex effects of this phenotype on tumor neovascularization following irradiation. PMID:19628926

  19. 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

  20. Suppression of Gαs Synthesis by Simvastatin Treatment of Vascular Endothelial Cells*

    PubMed Central

    Kou, Ruqin; Shiroto, Takashi; Sartoretto, Juliano L.; Michel, Thomas

    2012-01-01

    These studies explore the effects of statins on cyclic AMP-modulated signaling pathways in vascular endothelial cells. We previously observed (Kou, R., Sartoretto, J., and Michel, T. (2009) J. Biol. Chem. 284, 14734–14743) that simvastatin treatment of endothelial cells leads to a marked decrease in PKA-modulated phosphorylation of the protein VASP. Here we show that long-term treatment of mice with simvastatin attenuates the vasorelaxation response to the β-adrenergic agonist isoproterenol, without affecting endothelin-induced vasoconstriction or carbachol-induced vasorelaxation. We found that statin treatment of endothelial cells dose-dependently inhibits PKA activation as assessed by analyses of serine 157 VASP phosphorylation as well as Epac-mediated Rap1 activation. These effects of simvastatin are completely reversed by mevalonate and by geranylgeranyl pyrophosphate, implicating geranylgeranylation as a critical determinant of the stain response. We used biochemical approaches as well as fluorescence resonance energy transfer (FRET) methods with a cAMP biosensor to show that simvastatin treatment of endothelial cells markedly inhibits cAMP accumulation in response to epinephrine. Importantly, simvastatin treatment significantly decreases Gαs abundance, without affecting other Gα subunits. Simvastatin treatment does not influence Gαs protein stability, and paradoxically increases the abundance of Gαs mRNA. Finally, we found that simvastatin treatment inhibits Gαs translation mediated by Akt/mTOR/eIF4/4EBP. Taken together, these findings establish a novel mechanism by which simvastatin modulates β-adrenergic signaling in vascular wall, and may have implications for cardiovascular therapeutics. PMID:22144680

  1. In-vivo cell tracking to quantify endothelial cell migration during zebrafish angiogenesis

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    The mechanism of endothelial cell migration as individual cells or collectively while remaining an integral component of a functional blood vessel has not been well characterized. In this study, our overarching goal is to define an image processing workflow to facilitate quantification of how endothelial cells within the first aortic arch and are proximal to the zebrafish heart behave in response to the onset of flow (i.e. onset of heart beating). Endothelial cell imaging was conducted at this developmental time-point i.e. ~24-28 hours post fertilization (hpf) when flow first begins, using 3D+time two-photon confocal microscopy of a live, wild-type, transgenic, zebrafish expressing green fluorescent protein (GFP) in endothelial cell nuclei. An image processing pipeline comprised of image signal enhancement, median filtering for speckle noise reduction, automated identification of the nuclei positions, extraction of the relative movement of nuclei between consecutive time instances, and finally tracking of nuclei, was designed for achieving the tracking of endothelial cell nuclei and the identification of their movement towards or away from the heart. Pilot results lead to a hypothesis that upon the onset of heart beat and blood flow, endothelial cells migrate collectively towards the heart (by 21.51+/-10.35 μm) in opposition to blood flow (i.e. subtending 142.170+/-21.170 with the flow direction).

  2. 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

  3. WR-1065 and radioprotection of vascular endothelial cells. II. Morphology

    SciTech Connect

    Mooteri, S.N.; Podolski, J.L.; Drab, E.A.; Saclarides, T.J.

    1996-02-01

    Although the aminothiol WR-1065 protects normal tissues, its direct effect on the damage and restoration of the vascular endothelium is not clear. In endothelial cells, WR-1065 attenuates both the DNA damage and the G{sub 1}-phase arrest induced by radiation. After the destruction of nearby endothelial cells, the survivors rearrange their cytoskeleton, migrate and replicate. To determine the effect of radiation on morphology and migration, portions of bovine aortic endothelial cell cultures were denuded with a pipette tip and irradiated ({sup 137}Cs {gamma} rays). The following observations were noted after 5 Gy: within 10 min, there was increased formation of protein-mixed disulfides including actin-mixed disulfide; after 30 min, {alpha}{sub 5}{Beta}{sub 1}, the integrin receptor for fibronectin, was up-regulated on the apical membrane surface. Within 5 h, actin-containing stress fibers reorganized, although there was no change in the total filamentous (F-)actin content within the cells. Compared to controls after 24 h, the irradiated cells had migrated 15% farther (P < 0.01), and at the leading edge covered twice the surface area (P < 0.0001). The addition of 2 mM WR-1065 for 2 h before 5 Gy inhibited the increased expression of {alpha}{sub 5}{Beta}{sub 1}, promoted retention of stress fibers and prevented the enhanced cell migration and spreading. These results indicate that WR-1065 prevents radiation-induced morphological responses. This effect appears to be mediated by an impact on both adhesion molecule expression and cytoskeletal reorganization. 61 refs., 6 figs.

  4. Glycoproteomic Analysis of the Secretome of Human Endothelial Cells*

    PubMed Central

    Yin, Xiaoke; Bern, Marshall; Xing, Qiuru; Ho, Jenny; Viner, Rosa; Mayr, Manuel

    2013-01-01

    Previous proteomics studies have partially unraveled the complexity of endothelial protein secretion but have not investigated glycosylation, a key modification of secreted and membrane proteins for cell communication. In this study, human umbilical vein endothelial cells were kept in serum-free medium before activation by phorbol-12-myristate-13 acetate, a commonly used secretagogue that induces exocytosis of endothelial vesicles. In addition to 123 secreted proteins, the secretome was particularly rich in membrane proteins. Glycopeptides were enriched by zwitterionic hydrophilic interaction liquid chromatography resins and were either treated with PNGase F and H218O or directly analyzed using a recently developed workflow combining higher-energy C-trap dissociation (HCD) with electron-transfer dissociation (ETD) for a hybrid linear ion trap–orbitrap mass spectrometer. After deglycosylation with PNGase F in the presence of H218O, 123 unique peptides displayed 18O-deamidation of asparagine, corresponding to 86 proteins with a total of 121 glycosylation sites. Direct glycopeptide analysis via HCD-ETD identified 131 glycopeptides from 59 proteins and 118 glycosylation sites, of which 41 were known, 51 were predicted, and 26 were novel. Two methods were compared: alternating HCD-ETD and HCD-product-dependent ETD. The former detected predominantly high-intensity, multiply charged glycopeptides, whereas the latter preferentially selected precursors with complex/hybrid glycans for fragmentation. Validation was performed by means of glycoprotein enrichment and analysis of the input, the flow-through, and the bound fraction. This study represents the most comprehensive characterization of endothelial protein secretion to date and demonstrates the potential of new HCD-ETD workflows for determining the glycosylation status of complex biological samples. PMID:23345538

  5. Elevated Sodium and Dehydration Stimulate Inflammatory Signaling in Endothelial Cells and Promote Atherosclerosis

    PubMed Central

    Dmitrieva, Natalia I.; Burg, Maurice B.

    2015-01-01

    Cardiovascular diseases (CVDs) are a leading health problem worldwide. Epidemiologic studies link high salt intake and conditions predisposing to dehydration such as low water intake, diabetes and old age to increased risk of CVD. Previously, we demonstrated that elevation of extracellular sodium, which is a common consequence of these conditions, stimulates production by endothelial cells of clotting initiator, von Willebrand Factor, increases its level in blood and promotes thrombogenesis. In present study, by PCR array, using human umbilical vein endothelial cells (HUVECs), we analyzed the effect of high NaCl on 84 genes related to endothelial cell biology. The analysis showed that the affected genes regulate many aspects of endothelial cell biology including cell adhesion, proliferation, leukocyte and lymphocyte activation, coagulation, angiogenesis and inflammatory response. The genes whose expression increased the most were adhesion molecules VCAM1 and E-selectin and the chemoattractant MCP-1. These are key participants in the leukocyte adhesion and transmigration that play a major role in the inflammation and pathophysiology of CVD, including atherosclerosis. Indeed, high NaCl increased adhesion of mononuclear cells and their transmigration through HUVECs monolayers. In mice, mild water restriction that elevates serum sodium by 5 mmol/l, increased VCAM1, E-selectin and MCP-1 expression in mouse tissues, accelerated atherosclerotic plaque formation in aortic root and caused thickening or walls of coronary arteries. Multivariable linear regression analysis of clinical data from the Atherosclerosis Risk in Communities Study (n=12779) demonstrated that serum sodium is a significant predictor of 10 Years Risk of coronary heart disease. These findings indicate that elevation of extracellular sodium within the physiological range is accompanied by vascular changes that facilitate development of CVD. The findings bring attention to serum sodium as a risk factor for

  6. 3D map of the human corneal endothelial cell.

    PubMed

    He, Zhiguo; Forest, Fabien; Gain, Philippe; Rageade, Damien; Bernard, Aurélien; Acquart, Sophie; Peoc'h, Michel; Defoe, Dennis M; Thuret, Gilles

    2016-01-01

    Corneal endothelial cells (CECs) are terminally differentiated cells, specialized in regulating corneal hydration and transparency. They are highly polarized flat cells that separate the cornea from the aqueous humor. Their apical surface, in contact with aqueous humor is hexagonal, whereas their basal surface is irregular. We characterized the structure of human CECs in 3D using confocal microscopy of immunostained whole corneas in which cells and their interrelationships remain intact. Hexagonality of the apical surface was maintained by the interaction between tight junctions and a submembraneous network of actomyosin, braced like a drum. Lateral membranes, which support enzymatic pumps, presented complex expansions resembling interdigitated foot processes at the basal surface. Using computer-aided design and drafting software, we obtained a first simplified 3D model of CECs. By comparing their expression with those in epithelial, stromal and trabecular corneal cells, we selected 9 structural or functional proteins for which 3D patterns were specific to CECs. This first 3D map aids our understanding of the morphologic and functional specificity of CECs and could be used as a reference for characterizing future cell therapy products destined to treat endothelial dysfunctions. PMID:27381832

  7. 3D map of the human corneal endothelial cell

    PubMed Central

    He, Zhiguo; Forest, Fabien; Gain, Philippe; Rageade, Damien; Bernard, Aurélien; Acquart, Sophie; Peoc’h, Michel; Defoe, Dennis M.; Thuret, Gilles

    2016-01-01

    Corneal endothelial cells (CECs) are terminally differentiated cells, specialized in regulating corneal hydration and transparency. They are highly polarized flat cells that separate the cornea from the aqueous humor. Their apical surface, in contact with aqueous humor is hexagonal, whereas their basal surface is irregular. We characterized the structure of human CECs in 3D using confocal microscopy of immunostained whole corneas in which cells and their interrelationships remain intact. Hexagonality of the apical surface was maintained by the interaction between tight junctions and a submembraneous network of actomyosin, braced like a drum. Lateral membranes, which support enzymatic pumps, presented complex expansions resembling interdigitated foot processes at the basal surface. Using computer-aided design and drafting software, we obtained a first simplified 3D model of CECs. By comparing their expression with those in epithelial, stromal and trabecular corneal cells, we selected 9 structural or functional proteins for which 3D patterns were specific to CECs. This first 3D map aids our understanding of the morphologic and functional specificity of CECs and could be used as a reference for characterizing future cell therapy products destined to treat endothelial dysfunctions. PMID:27381832

  8. 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

  9. R-Ras inhibits VEGF-induced p38MAPK activation and HSP27 phosphorylation in endothelial cells

    PubMed Central

    Sawada, Junko; Li, Fangfei; Komatsu, Masanobu

    2016-01-01

    R-Ras is a Ras family small GTPase highly expressed in mature functional blood vessels in normal tissues. It inhibits pathological angiogenesis and promotes vessel maturation and stabilization. Previous studies suggest that R-Ras affects cellular signaling in endothelial cells, pericytes, and smooth muscle cells to regulate vessel formation and remodeling in adult tissues. R-Ras suppresses VEGF-induced endothelial permeability and vessel sprouting while promoting normalization of pathologically developing vessels in mice. R-Ras attenuates VEGF receptor-2 (VEGFR2) activation by inhibiting internalization of the receptor upon VEGF ligand binding, leading to significant reduction of VEGFR2 autophosphorylation. Here, we show that R-Ras strongly suppresses VEGF-dependent activation of stress-activated protein kinase-2/p38 mitogen-activated protein kinase (SAPK2/p38MAPK) and phosphorylation of downstream heat shock protein 27 (HSP27), a regulator of actin cytoskeleton organization, in endothelial cells. The suppression of p38MAPK activation and HSP27 phosphorylation by R-Ras concurred with altered actin cytoskeleton architecture, reduced membrane protrusion, and inhibition of endothelial cell migration toward VEGF. Silencing of endogenous R-Ras by RNAi increased membrane protrusion and cell migration stimulated by VEGF, and these effects were offset by p38MAPK inhibitor SB203580. These results suggest that R-Ras regulates angiogenic activities of endothelial cells in part via inhibition of the p38MAPK-HSP27 axis of VEGF signaling. PMID:27029009

  10. Quantitative & qualitative analysis of endothelial cells of donor cornea before & after penetrating keratoplasty in different pathological conditions

    PubMed Central

    Gupta, Aruna K.R.; Gupta, Roopam K.R.

    2016-01-01

    Background & objectives: Endothelial cells of the donor cornea are known to be affected quantitatively and qualitatively in different pathological conditions after penetrating keratoplasty (PK) and this has direct effect on the clarity of vision obtained after PK. This study was undertaken to analyze the qualitative and quantitative changes in donor endothelial cells before and after PK in different pathological conditions. Methods: A prospective investigational analysis of 100 consecutive donor corneas used for penetrating keratoplasty between June 2006 and June 2008, was conducted. The patients were evaluated on the first day, at the end of first week, first month, third and six months and one year. Results: A decrease was observed in endothelial cell count in all pathological conditions. After one year of follow up the loss was 33.1 per cent in corneal opacity, 45.9 per cent in acute infective keratitis (AIK), 58.5 per cent in regrafts, 28.5 per cent in pseudophakic bullous keratopathy (PBK), 37 per cent in descemetocele, 27 per cent in keratoconus and 35.5 per cent in aphakic bullous keratopathy (ABK) cases. Interpretation & conclusions: The endothelial cell loss was highest in regraft cases which was significant (P<0.05), while the least endothelial cell loss was seen in keratoconus cases. The cell loss was associated with increase in coefficient of variation (CV), i.e. polymegathism and pleomorphism. Inspite of this polymegathism and pleomorphism, the clarity of the graft was maintained. PMID:27121519

  11. 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

  12. 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

  13. R-Ras Inhibits VEGF-Induced p38MAPK Activation and HSP27 Phosphorylation in Endothelial Cells.

    PubMed

    Sawada, Junko; Li, Fangfei; Komatsu, Masanobu

    2015-01-01

    R-Ras is a Ras family small GTPase that is highly expressed in mature functional blood vessels in normal tissues. It inhibits pathological angiogenesis and promotes vessel maturation and stabilization. Previous studies suggest that R-Ras affects cellular signaling in endothelial cells, pericytes and smooth-muscle cells to regulate vessel formation and remodeling in adult tissues. R-Ras suppresses VEGF-induced endothelial permeability and vessel sprouting while promoting normalization of pathologically developing vessels in mice. It attenuates VEGF receptor-2 (VEGFR2) activation by inhibiting internalization of the receptor upon VEGF ligand binding, leading to significant reduction of VEGFR2 autophosphorylation. Here, we show that R-Ras strongly suppresses the VEGF-dependent activation of stress-activated protein kinase-2/p38 mitogen-activated protein kinase (SAPK2/p38MAPK) and the phosphorylation of downstream heat-shock protein 27 (HSP27), a regulator of actin cytoskeleton organization, in endothelial cells. The suppression of p38MAPK activation and HSP27 phosphorylation by R-Ras concurred with altered actin cytoskeleton architecture, reduced membrane protrusion and inhibition of endothelial cell migration toward VEGF. Silencing of endogenous R-Ras by RNA interference increased membrane protrusion and cell migration stimulated by VEGF, and these effects were offset by p38MAPK inhibitor SB203580. These results suggest that R-Ras regulates angiogenic activities of endothelial cells in part via inhibition of the p38MAPK-HSP27 axis of VEGF signaling. PMID:27029009

  14. Disruption of cytoskeletal structures mediates shear stress-induced endothelin-1 gene expression in cultured porcine aortic endothelial cells.

    PubMed Central

    Morita, T; Kurihara, H; Maemura, K; Yoshizumi, M; Yazaki, Y

    1993-01-01

    Hemodynamic shear stress alters the architecture and functions of vascular endothelial cells. We have previously shown that the synthesis of endothelin-1 (ET-1) in endothelial cells is increased by exposure to shear stress. Here we examined whether shear stress-induced alterations in cytoskeletal structures are responsible for increases in ET-1 synthesis in cultured porcine aortic endothelial cells. Exposure of endothelial cells to 5 dyn/cm2 of low shear stress rapidly increased monomeric G-actin contents within 5 min without changing total actin contents. The ratio of G- to total actin, 54 +/- 0.8% in quiescent endothelial cells, increased to 87 +/- 4.2% at 6 h and then decreased. Following the disruption of filamentous (F)-actin into G-actin, ET-1 mRNA levels in endothelial cells also increased within 30 min and reached a peak at 6 h. The F-actin stabilizer, phalloidin, abolished shear stress-induced increases in ET-1 mRNA; however, it failed to inhibit increases in ET-1 mRNA secondary to other stimulants. This indicates that shear stress-induced increases in ET-1 mRNA levels may be mediated by the disruption of actin fibers. Furthermore, increases in ET-1 gene expression can be induced by actin-disrupting agents, cytochalasin B and D. Another cytoskeleton-disrupting agent, colchicine, which inhibits dimerization of tubulin, did not affect the basal level of ET-1 mRNA. However, colchicine completely inhibited shear stress- and cytochalasin B-induced increases in ET-1 mRNA levels. These results suggest that shear stress-induced ET-1 gene expression in endothelial cells is mediated by the disruption of actin cytoskeleton and this induction is dependent on the integrity of microtubules. Images PMID:8408624

  15. Exocytosis of endothelial cells is regulated by N-ethylmaleimide-sensitive factor.

    PubMed

    Yamakuchi, Munekazu; Ferlito, Marcella; Morrell, Craig N; Matsushita, Kenji; Fletcher, Craig A; Cao, Wangsen; Lowenstein, Charles J

    2008-01-01

    Endothelial exocytosis of granules is a rapid response to vascular injury. However, the molecular machinery that regulates exocytosis in endothelial cells is not well understood. Recently developed techniques have defined the endothelial proteins that control vesicle and granule trafficking in endothelial cells. These techniques have revealed that syntaxin 4, synaptobrevin 3, and N-ethylmaleimide-sensitive factor (NSF) play a critical role in endothelial granule exocytosis. Additional studies have shown that nitric oxide regulates exocytosis by chemically modifying NSF. Further characterization of the factors that regulate exocytosis will lead to novel treatments for vascular diseases such as myocardial infarction and stroke. PMID:18369947

  16. Cell-Based Screening Identifies Paroxetine as an Inhibitor of Diabetic Endothelial Dysfunction

    PubMed Central

    Gerö, Domokos; Szoleczky, Petra; Suzuki, Kunihiro; Módis, Katalin; Oláh, Gabor; Coletta, Ciro; Szabo, Csaba

    2013-01-01

    We have conducted a phenotypic screening in endothelial cells exposed to elevated extracellular glucose (an in vitro model of hyperglycemia) to identify compounds that prevent hyperglycemia-induced reactive oxygen species (ROS) formation without adversely affecting cell viability. From a focused library of >6,000 clinically used drug-like and pharmacologically active compounds, several classes of active compounds emerged, with a confirmed hit rate of <0.5%. Follow-up studies focused on paroxetine, a clinically used antidepressant compound that has not been previously implicated in the context of hyperglycemia or diabetes. Paroxetine reduced hyperglycemia-induced mitochondrial ROS formation, mitochondrial protein oxidation, and mitochondrial and nuclear DNA damage, without interfering with mitochondrial electron transport or cellular bioenergetics. The ability of paroxetine to improve hyperglycemic endothelial cell injury was unique among serotonin reuptake blockers and can be attributed to its antioxidant effect, which primarily resides within its sesamol moiety. Paroxetine maintained the ability of vascular rings to respond to the endothelium-dependent relaxant acetylcholine, both during in vitro hyperglycemia and ex vivo, in a rat model of streptozotocin-induced diabetes. Thus, the current work identifies a novel pharmacological action of paroxetine as a protector of endothelial cells against hyperglycemic injury and raises the potential of repurposing of this drug for the experimental therapy of diabetic cardiovascular complications. PMID:23223176

  17. Endothelial cells are progenitors of cardiac pericytes and vascular smooth muscle cells.

    PubMed

    Chen, Qi; Zhang, Hui; Liu, Yang; Adams, Susanne; Eilken, Hanna; Stehling, Martin; Corada, Monica; Dejana, Elisabetta; Zhou, Bin; Adams, Ralf H

    2016-01-01

    Mural cells of the vessel wall, namely pericytes and vascular smooth muscle cells, are essential for vascular integrity. The developmental sources of these cells and molecular mechanisms controlling their progenitors in the heart are only partially understood. Here we show that endocardial endothelial cells are progenitors of pericytes and vascular smooth muscle cells in the murine embryonic heart. Endocardial cells undergo endothelial-mesenchymal transition and convert into primitive mesenchymal progenitors expressing the platelet-derived growth factor receptors, PDGFRα and PDGFRβ. These progenitors migrate into the myocardium, differentiate and assemble the wall of coronary vessels, which requires canonical Wnt signalling involving Frizzled4, β-catenin and endothelial cell-derived Wnt ligands. Our findings identify a novel and unexpected population of progenitors for coronary mural cells with potential relevance for heart function and disease conditions. PMID:27516371

  18. Collaborative Enhancement of Endothelial Targeting of Nanocarriers by Modulating Platelet-Endothelial Cell Adhesion Molecule-1/CD31 Epitope Engagement.

    PubMed

    Chacko, Ann-Marie; Han, Jingyan; Greineder, Colin F; Zern, Blaine J; Mikitsh, John L; Nayak, Madhura; Menon, Divya; Johnston, Ian H; Poncz, Mortimer; Eckmann, David M; Davies, Peter F; Muzykantov, Vladimir R

    2015-07-28

    Nanocarriers (NCs) coated with antibodies (Abs) to extracellular epitopes of the transmembrane glycoprotein PECAM (platelet endothelial cell adhesion molecule-1/CD31) enable targeted drug delivery to vascular endothelial cells. Recent studies revealed that paired Abs directed to adjacent, yet distinct epitopes of PECAM stimulate each other's binding to endothelial cells in vitro and in vivo ("collaborative enhancement"). This phenomenon improves targeting of therapeutic fusion proteins, yet its potential role in targeting multivalent NCs has not been addressed. Herein, we studied the effects of Ab-mediated collaborative enhancement on multivalent NC spheres coated with PECAM Abs (Ab/NC, ∼180 nm diameter). We found that PECAM Abs do mutually enhance endothelial cell binding of Ab/NC coated by paired, but not "self" Ab. In vitro, collaborative enhancement of endothelial binding of Ab/NC by paired Abs is modulated by Ab/NC avidity, epitope selection, and flow. Cell fixation, but not blocking of endocytosis, obliterated collaborative enhancement of Ab/NC binding, indicating that the effect is mediated by molecular reorganization of PECAM molecules in the endothelial plasmalemma. The collaborative enhancement of Ab/NC binding was affirmed in vivo. Intravascular injection of paired Abs enhanced targeting of Ab/NC to pulmonary vasculature in mice by an order of magnitude. This stimulatory effect greatly exceeded enhancement of Ab targeting by paired Abs, indicating that '"collaborative enhancement"' effect is even more pronounced for relatively large multivalent carriers versus free Abs, likely due to more profound consequences of positive alteration of epitope accessibility. This phenomenon provides a potential paradigm for optimizing the endothelial-targeted nanocarrier delivery of therapeutic agents. PMID:26153796

  19. Virulent Treponema pallidum promotes adhesion of leukocytes to human vascular endothelial cells.

    PubMed Central

    Riley, B S; Oppenheimer-Marks, N; Radolf, J D; Norgard, M V

    1994-01-01

    Perivasculitis and endothelial cell abnormalities are characteristic histopathologic features of syphilis, a sexually transmitted disease caused by Treponema pallidum. To extend earlier studies demonstrating that T. pallidum activates endothelial cells, we now show that virulent T. pallidum, but not heat-killed T. pallidum or nonpathogenic Treponema phagedenis, promotes increased adherence of lymphocytes and monocytes to human umbilical vein endothelial cells. Lymphocytes and monocytes are the two cell types prominent in the histopathology of syphilis. Recognition that T. pallidum can stimulate endothelial cells to bind leukocytes provides important insights into the early mechanisms of syphilis immunopathogenesis. Images PMID:7927729

  20. Mechanotransductional Basis of Endothelial Cell Response to Intravascular Bubbles

    PubMed Central

    Klinger, Alexandra L.; Pichette, Benjamin; Sobolewski, Peter; Eckmann, David M.

    2011-01-01

    Vascular air embolism resulting from too rapid decompression is a well-known risk in deep-sea diving, aviation and space travel. It is also a common complication during surgery or other medical procedures when air or other endogenously administered gas is entrained in the circulation. Preventive and post-event treatment options are extremely limited for this dangerous condition, and none of them address the poorly understood pathophysiology of endothelial response to intravascular bubble presence. Using a novel apparatus allowing precise manipulation of microbubbles in real time fluorescence microscopy studies, we directly measure human umbilical vein endothelial cell responses to bubble contact. Strong intracellular calcium transients requiring extracellular calcium are observed upon cell-bubble interaction. The transient is eliminated both by the presence of the stretch activated channel inhibitor, gadolinium, and the transient receptor potential vanilliod family inhibitor, ruthenium red. No bubble induced calcium upsurge occurs if the cells are pretreated with an inhibitor of actin polymerization, cytochalasin-D. This study explores the biomechanical mechanisms at play in bubble interfacial interactions with endothelial surface layer (ESL) macromolecules, reassessing cell response after selective digestion of glycocalyx glycosoaminoglycans, hyaluran (HA) and heparin sulfate (HS). HA digestion causes reduction of cell-bubble adherence and a more rapid induction of calcium influx after contact. HS depletion significantly decreases calcium transient amplitudes, as does pharmacologically induced sydencan ectodomain shedding. The surfactant perfluorocarbon oxycyte abolishes any bubble induced calcium transient, presumably through direct competition with ESL macromolecules for interfacial occupancy, thus attenuating the interactions that trigger potentially deleterious biochemical pathways. PMID:21931900

  1. Signal transduction pathways in mast cell granule-mediated endothelial cell activation.

    PubMed Central

    Chi, Luqi; Stehno-Bittel, Lisa; Smirnova, Irina; Stechschulte, Daniel J; Dileepan, Kottarappat N

    2003-01-01

    BACKGROUND: We have previously shown that incubation of human endothelial cells with mast cell granules results in potentiation of lipopolysaccharide-induced production of interleukin-6 and interleukin-8. AIMS: The objective of the present study was to identify candidate molecules and signal transduction pathways involved in the synergy between mast cell granules and lipopolysaccharide on endothelial cell activation. METHODS: Human umbilical vein endothelial cells were incubated with rat mast cell granules in the presence and absence of lipopolysaccharide, and IL-6 production was quantified. The status of c-Jun amino-terminal kinase and extracellular signal-regulated kinase 1/2 activation, nuclear factor-kappaB translocation and intracellular calcium levels were determined to identify the mechanism of synergy between mast cell granules and lipopolysaccaride. RESULTS: Mast cell granules induced low levels of interleukin-6 production by endothelial cells, and this effect was markedly enhanced by lipopolysaccharide. The results revealed that both serine proteases and histamine present in mast cell granules were involved in this activation process. Mast cell granules increased intracellular calcium, and activated c-Jun amino-terminal kinase and extracellular signal-regulated kinase 1/2. The combination of lipopolysaccharide and mast cell granules prolonged c-Jun amino-terminal kinase activity beyond the duration of induction by either stimulant alone and was entirely due to active proteases. However, both proteases and histamine contributed to calcium mobilization and extracellular signal-regulated kinase 1/2 activation. The nuclear translocation of nuclear factor-kappaB proteins was of greater magnitude in endothelial cells treated with the combination of mast cell granules and lipopolysaccharide. CONCLUSIONS:Mast cell granule serine proteases and histamine can amplify lipopolysaccharide-induced endothelial cell activation, which involves calcium mobilization, mitogen

  2. Alloproliferation of purified CD4+ T cells to adult human heart endothelial cells, and study of second-signal requirements.

    PubMed Central

    McDouall, R M; Page, C S; Hafizi, S; Yacoub, M H; Rose, M L

    1996-01-01

    Human endothelial cells have been shown to be capable of causing direct allostimulation of T cells. However, the majority of immunological studies of human endothelial cells have been performed on cells of fetal origin. Here we use endothelial cells isolated from the adult human heart, both large vessel (coronary artery, pulmonary artery and aorta) and also microvascular. We have examined the ability of all these endothelial cells to cause direct allostimulation of T cells, and show that purified CD4+ T cells can proliferate in response to adult human heart endothelial cells, the response being dependent on pretreatment of the endothelial cells with interferon-gamma (IFN-gamma) and inhibited by anti-HLA-DR monoclonal antibody. The proliferative responses of CD8+ T cells to adult but not fetal endothelial cells was inconsistent and weak. Proliferative responses were not blocked by CTLA4-Ig, which inhibits T-cell responses to "classical' antigen-presenting cells (APC), but > 50% inhibition was achieved with monoclonal antibody to lymphocyte function-associated antigen-3 (LFA-3). These results show that adult human cardiovascular endothelial cells are capable of causing allostimulation of resting CD4+ T cells, using a different second signal to classical APC. In view of these findings endothelial cells should be considered as APC following solid organ transplantation. PMID:8943718

  3. Intersectin Regulates Fission and Internalization of Caveolae in Endothelial Cells

    PubMed Central

    Predescu, Sanda A.; Predescu, Dan N.; Timblin, Barbara K.; Stan, Radu V.; Malik, Asrar B.

    2003-01-01

    Intersectin, a multiple Eps15 homology and Src homology 3 (SH3) domain–containing protein, is a component of the endocytic machinery in neurons and nonneuronal cells. However, its role in endocytosis via caveolae in endothelial cells (ECs) is unclear. We demonstrate herein by coimmunoprecipitation, velocity sedimentation on glycerol gradients, and cross-linking that intersectin is present in ECs in a membrane-associated protein complex containing dynamin and SNAP-23. Electron microscopy (EM) immunogold labeling studies indicated that intersectin associated preferentially with the caveolar necks, and it remained associated with caveolae after their fission from the plasmalemma. A cell-free system depleted of intersectin failed to support caveolae fission from the plasma membrane. A biotin assay used to quantify caveolae internalization and extensive EM morphological analysis of ECs overexpressing wt-intersectin indicated a wide range of morphological changes (i.e., large caveolae clusters marginated at cell periphery and pleiomorphic caveolar necks) as well as impaired caveolae internalization. Biochemical evaluation of caveolae-mediated uptake by ELISA showed a 68.4% inhibition by reference to control. We also showed that intersectin interaction with dynamin was important in regulating the fission and internalization of caveolae. Taken together, the results indicate the crucial role of intersectin in the mechanism of caveolae fission in endothelial cells. PMID:12960435

  4. Recombinant Treponema pallidum Protein Tp0965 Activates Endothelial Cells and Increases the Permeability of Endothelial Cell Monolayer

    PubMed Central

    Zhang, Rui-Li; Zhang, Jing-Ping; Wang, Qian-Qiu

    2014-01-01

    The recombinant Treponema pallidum protein Tp0965 (rTp0965), one of the many proteins derived from the genome of T. pallidum subsp. pallidum, shows strong immunogenicity and immunoreactivity. In this study, we investigated the effects of rTp0965 on the endothelial barrier. Treatment of human umbilical vein endothelial cells (HUVECs) with rTp0965 resulted in increased levels of ICAM-1, E-selectin, and MCP-1 mRNA and protein expression. These increases contributed to the adhesion and chemataxis of monocytes (THP-1 cells) to HUVECs preincubated with rTp0965. In addition, rTp0965 induced reorganization of F-actin and decreased expression of claudin-1 in HUVECs. Interestingly, inhibition of the RhoA/ROCK signal pathway protected against rTp0965-induced higher endothelial permeability as well as transendothelial migration of monocytes. These data indicate that Tp0965 protein may play an important role in the immunopathogenesis of syphilis. PMID:25514584

  5. Recombinant Treponema pallidum protein Tp0965 activates endothelial cells and increases the permeability of endothelial cell monolayer.

    PubMed

    Zhang, Rui-Li; Zhang, Jing-Ping; Wang, Qian-Qiu

    2014-01-01

    The recombinant Treponema pallidum protein Tp0965 (rTp0965), one of the many proteins derived from the genome of T. pallidum subsp. pallidum, shows strong immunogenicity and immunoreactivity. In this study, we investigated the effects of rTp0965 on the endothel