ADAMTS13 Promotes Angiogenesis and Modulates VEGF-Mediated Angiogenic Activities

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1145-1145
Author(s):  
Manfai Lee ◽  
Jonathan Baza ◽  
George M. Rodgers

Abstract Abstract 1145 Severe plasma ADAMTS13 deficiency results in the clinical disorder thrombotic thrombocytopenic purpura. However, other potential pathophysiological roles of ADAMTS13 in endothelial cell biology remain unexplored. To assess the possible role of ADAMTS13 in angiogenesis, cell proliferation and migration of human umbilical vein endothelial cells (HUVEC) were studied in vitro. ADAMTS13 was found to be a highly potent chemoattractant, and additionally was capable of neutralizing VEGF activity in two angiogenesis assays-cell proliferation and cell migration. In the Boyden chamber cell migration assay, treatment of endothelial cells with exogenous recombinant ADAMTS13 promoted cell migration in a dose-dependent manner, with 1 ng/mL increasing cell migration across a gelatinized polycarbonate membrane by 14-fold. In the same model, 5 ng/mL VEGF165 (molar ratio of ADAMTS13:VEGF165 = 1/19) only increased cell migration by 7 fold. A steady decrease in endothelial cell migration was observed when the concentration of ADAMTS13 exceeded 1 ng/mL (Figure 1). Coincubation of 30 ng/mL ADAMTS13 with 6.16 ng/mL VEGF165 (molar ratio of ADAMTS13/VEGF165 = 1.3/1) inhibited endothelial cell migration by 45% compared to VEGF alone (Figure 2). A second model using an in vitro scratch-wound assay confirmed the Boyden chamber data. Substitution of ADAMTS13 with ADAM17, an analog of ADAMTS13 without the thrombospondin domain reversed the inhibition of VEGF-mediated cell migration, suggesting that the thrombospondin domain of ADAMTS13 is responsible for the inhibitory interaction with VEGF165. This finding was in agreement with our previously published co-immunoprecipitation assay data (Blood 2010, 116, 4307). Similar patterns of inhibition were observed with VEGF121 and VEGF189, indicating that other isoforms of VEGF may interact with the TSP domain of ADAMTS13. Using a manual proliferation assay method, HUVEC treated with 30 ng/mL ADAMTS13 and 6.16 ng/mL VEGF165 proliferated 40% slower than the control treated with VEGF alone. Combined with our findings on the inhibition of endothelial cell-tube formation in a Matrigel assay with ADAMTS13 and VEGF165 previously reported, our cumulative data suggest that 1) ADAMTS13 promotes angiogenesis by increasing cell migration and 2) ADAMTS13 can modulate VEGF-mediated angiogenic activities. Disclosures: No relevant conflicts of interest to declare.

2000 ◽  
Vol 113 (1) ◽  
pp. 59-69 ◽  
Author(s):  
M.F. Carlevaro ◽  
S. Cermelli ◽  
R. Cancedda ◽  
F. Descalzi Cancedda

Vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) induces endothelial cell migration and proliferation in culture and is strongly angiogenic in vivo. VEGF synthesis has been shown to occur in both normal and transformed cells. The receptors for the factor have been shown to be localized mainly in endothelial cells, however, the presence of VEGF synthesis and the VEGF receptor in cells other than endothelial cells has been demonstrated. Neoangiogenesis in cartilage growth plate plays a fundamental role in endochondral ossification. We have shown that, in an avian in vitro system for chondrocyte differentiation, VEGF was produced and localized in cell clusters totally resembling in vivo cartilage. The factor was synthesized by hypertrophic chondrocytes and was released into their conditioned medium, which is highly chemotactic for endothelial cells. Antibodies against VEGF inhibited endothelial cell migration induced by chondrocyte conditioned media. Similarly, endothelial cell migration was inhibited also by antibodies directed against the VEGF receptor 2/Flk1 (VEGFR2). In avian and mammalian embryo long bones, immediately before vascular invasion, VEGF was distinctly localized in growth plate hypertrophic chondrocytes. In contrast, VEGF was not observed in quiescent and proliferating chondrocytes earlier in development. VEGF receptor 2 colocalized with the factor both in hypertrophic cartilage in vivo and hypertrophic cartilage engineered in vitro, suggesting an autocrine loop in chondrocytes at the time of their maturation to hypertrophic cells and of cartilage erosion. Regardless of cell exposure to exogenous VEGF, VEGFR-2 phosphorylation was recognized in cultured hypertrophic chondrocytes, supporting the idea of an autocrine functional activation of signal transduction in this non-endothelial cell type as a consequence of the endogenous VEGF production. In summary we propose that VEGF is actively responsible for hypertrophic cartilage neovascularization through a paracrine release by chondrocytes, with invading endothelial cells as a target. Furthermore, VEGF receptor localization and signal transduction in chondrocytes strongly support the hypothesis of a VEGF autocrine activity also in morphogenesis and differentiation of a mesoderm derived cell.


2008 ◽  
Vol 99 (03) ◽  
pp. 576-585 ◽  
Author(s):  
Mathieu Provençal ◽  
Marisol Michaud ◽  
Édith Beaulieu ◽  
David Ratel ◽  
Georges-Étienne Rivard ◽  
...  

SummaryTissue factor pathway inhibitor (TFPI) is a plasma Kunitz-type serine protease inhibitor that is mainly known for its inhibition of tissue factor-mediated coagulation. In addition to its anticoagulant properties, emerging data show that TFPI may also regulate endothelial cell functions via a non-haemostatic pathway. In this work we demonstrate that at concentrations within the physiological range,TFPI inhibits both endothelial cell migration and their differentiation into capillary-like structures in vitro. These effects were specific to endothelial cells since no inhibitory effect was observed on the migration of tumor (glio- blastoma) cells. Inhibition of endothelial cell migration was correlated with a concomitant loss in cell adhesion,suggesting an alteration of focal adhesion complex integrity. Accordingly,we observed thatTFPI inhibited the phosphorylation of focal adhesion kinase and paxillin,two key proteins involved in the scaffolding of these complexes, and that this effect was specific to endothelial cells. These results suggest that TFPI influences the angiogenic process via a non-haemostatic pathway, by downregulating the migratory mechanisms of endothelial cells.


Blood ◽  
2010 ◽  
Vol 115 (20) ◽  
pp. 4130-4137 ◽  
Author(s):  
Jinmin Gao ◽  
Lei Sun ◽  
Lihong Huo ◽  
Min Liu ◽  
Dengwen Li ◽  
...  

Cylindromatosis (CYLD) is a deubiquitinase that was initially identified as a tumor suppressor and has recently been implicated in diverse normal physiologic processes. In this study, we have investigated the involvement of CYLD in angiogenesis, the formation of new blood vessels from preexisting ones. We find that knockdown of CYLD expression significantly impairs angiogenesis in vitro in both matrigel-based tube formation assay and collagen-based 3-dimensional capillary sprouting assay. Disruption of CYLD also remarkably inhibits angiogenic response in vivo, as evidenced by diminished blood vessel growth into the angioreactors implanted in mice. Mechanistic studies show that CYLD regulates angiogenesis by mediating the spreading and migration of vascular endothelial cells. Silencing of CYLD dramatically decreases microtubule dynamics in endothelial cells and inhibits endothelial cell migration by blocking the polarization process. Furthermore, we identify Rac1 activation as an important factor contributing to the action of CYLD in regulating endothelial cell migration and angiogenesis. Our findings thus uncover a previously unrecognized role for CYLD in the angiogenic process and provide a novel mechanism for Rac1 activation during endothelial cell migration and angiogenesis.


1980 ◽  
Vol 152 (4) ◽  
pp. 931-944 ◽  
Author(s):  
R G Azizkhan ◽  
J C Azizkhan ◽  
B R Zetter ◽  
J Folkman

Migration of capillary endothelial cells is an important component of angiogenesis in vivo. Increased numbers of mast cells have been associated with several types of angiogenesis. We have used a quantitative assay in vitro to demonstrate that mast cells release a factor that significantly increases bovine capillary endothelial cell migration. The factor is present in medium conditioned by mast cells as well as lysates of mast cells. The stimulatory effect of mast cells on migration is specific for capillary endothelial cells. Furthermore, mast cells have no mitogenic activity for capillary endothelial cells. Of all the secretory products of mast cells tested, only heparin stimulated capillary endothelial cell migration in vitro. Heparin preparations from a variety of sources stimulated capillary endothelial cell migration to the same degree but did not stimulate migration of several other cell types. The migration activity of heparin and mast cell conditioned medium was blocked by specific antagonists of heparin (protamine and heparinase), but not by chondroitinase ABC. The migration activity of mast cell conditioned medium was resistant to heat (100 degrees C) and incubation with proteolytic enzymes. These results suggest that the role of mast cells in angiogenesis may be to enhance migration of the endothelial cells of growing capillaries.


Cells ◽  
2019 ◽  
Vol 8 (4) ◽  
pp. 349
Author(s):  
Devandir A. de Souza Junior ◽  
Carolina Santana ◽  
Gabriel V. Vieira ◽  
Constance Oliver ◽  
Maria Celia Jamur

Previous studies from our laboratory have shown that during angiogenesis in vitro, rmMCP-7 (recombinant mouse mast cell protease-7) stimulates endothelial cell spreading and induces their penetration into the matrix. The ability of rmMCP-7 to induce angiogenesis in vivo was assessed in the present study using a directed in vivo angiogenesis assay (DIVAA™). Vessel invasion of the angioreactor was observed in the presence of rmMCP-7 but was not seen in the control. Since integrins are involved in endothelial cell migration, the relationship between rmMCP-7 and integrins during angiogenesis was investigated. Incubation with rmMCP-7 resulted in a reduction in the levels of integrin subunits αv and β1 on SVEC4-10 endothelial cells during angiogenesis in vitro. Furthermore, the degradation of integrin subunits occurs both through the direct action of rmMCP-7 and indirectly via the ubiquitin/proteasome system. Even in the presence of a proteasome inhibitor, incubation of endothelial cells with rmMCP-7 induced cell migration and tube formation as well as the beginning of loop formation. These data indicate that the direct degradation of the integrin subunits by rmMCP-7 is sufficient to initiate angiogenesis. The results demonstrate, for the first time, that mMCP-7 acts in angiogenesis through integrin degradation.


2011 ◽  
Vol 301 (5) ◽  
pp. C1086-C1092 ◽  
Author(s):  
A. M. Porter ◽  
C. M. Klinge ◽  
A. S. Gobin

Angiogenesis is an important biological response known to be involved in many physiological and pathophysiological situations. Cellular responses involved in the formation of new blood vessels, such as increases in endothelial cell proliferation, cell migration, and the survival of apoptosis-inducing events, have been associated with vascular endothelial growth factor isoform 165 (VEGF165). Current research in the areas of bioengineering and biomedical science has focused on developing polyethylene glycol (PEG)-based systems capable of initiating and sustaining angiogenesis in vitro. However, a thorough understanding of how endothelial cells respond at the molecular level to VEGF165 incorporated into these systems has not yet been established in the literature. The goal of the current study was to compare the upregulation of key intracellular proteins involved in angiogenesis in human umbilical vein endothelial cells (HUVEC) and human microvascular endothelial cells (HMEC) seeded on PEG hydrogels containing grafted VEGF165 and adhesion peptides Arg-Gly-Asp-Ser (RGDS). Our data suggest that the covalent incorporation of VEGF165 into PEG hydrogels encourages the upregulation of signaling proteins responsible for increases in endothelial cell proliferation, cell migration, and the survival after apoptosis-inducing events.


2017 ◽  
Vol 41 (4) ◽  
pp. 1346-1359 ◽  
Author(s):  
Li Ju ◽  
Zhiwen Zhou ◽  
Bo Jiang ◽  
Yue Lou ◽  
Xirong Guo

Background/Aims: Pro-angiogenic factors VEGF and IL-8 play a major role in modulating the migratory potential of endothelial cells. The goal of this study was to investigate the effect of autocrine VEGF and IL-8 in the form of self-conditioned medium (CM) on human umbilical vein endothelial cells (HUVECs). Methods: Enzyme-linked immunosorbent assay (ELISA) examined the automatic secretion of VEGF and IL-8 protein by HUVECs. Western blot, small interfering RNA (siRNA), pulldown and Transwell assays were used to explore the role and the mechanism of autocrine VEGF and IL-8 in migration of HUVECs. Results: Neutralizing VEGF and IL-8 in CM significantly abrogated CM-induced migration of HUVECs. Autocrine VEGF and IL-8 increased Src phosphorylation, Rac1 activity and PAK1 phosphorylation in a time dependent manner. Additionally, blocking Rac1 activity with Rac1 siRNA largely abolished autocrine VEGF and IL-8-induced cell migration. Vav2 siRNA suppressed autocrine VEGF and IL-8-induced Rac1 activation and cell migration. Furthermore, blocking Src signaling with PP2, a specific inhibitor for Src, markedly prevented autocrine VEGF and IL-8-induced Vav2 and Rac1 activation as well as consequently cell migration. PAK1 siRNA also significantly abolished autocrine VEGF and IL-8-induced cell migration. Conclusions: We demonstrated for the first time that autocrine VEGF and IL-8 promoted endothelial cell migration via the Src/Vav2/Rac1/PAK1 signaling pathway. This finding reveals the molecular mechanism in the increase of endothelial cell migration induced by autocrine growth factors and cytokines, which is expected to provide a novel therapeutic target in vascular diseases.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Jun-ichi Suehiro ◽  
Mai Miura ◽  
Tatsuhiko Kodama ◽  
Takashi Minami

Endothelium is a dynamic cell layer constantly responding to changes in the various extracellular mediators. Responses are usually beneficial to host, but oversustained or dysregulated responses can result in vascular dysfunction, leading to the initiation of atherosclerosis, tumor growth, and inflammation. Such endothelial cell activation and dysfunction are mediated in large part by alterations in gene expression. Here we show, using comprehensive transcriptome analyses, that VEGF, thrombin and TNF-α each induces a dramatic and rapid up-regulation of early growth response (Egr)-3 in human umbilical vein endothelial cells (HUVEC). The effect of VEGF on Egr-3 was similar in human coronary artery, pulmonary artery, and dermal microvascular endothelial cells. In chemical inhibitor studies, VEGF-mediated induction of Egr-3 (mRNA peak 300-fold at 45 min) depended on MEK1/2, JNK, PI3K, PKA, and Ca-calcineurin. Egr-3 promoter luciferase and electrophoretic mobility shift analysis revealed that the 5′-flanking region at −57 to −130 was necessary and sufficient for transducing of VEGF-mediated Egr-3 upregulation and that region could bind NFATc1, c2, and SRF. Co-transfection assays with Egr-3 reporter and either NFATc or SRF expression plasmids resulted in 4 and 2 -fold Egr-3 promoter activation, respectively. In DNA microarray studies, HUVEC treated with VEGF for 1 and 4 hours in the presence of two independent siRNAs against Egr-3, 25 and 70 VEGF-inducible genes were strikingly downregulated, respectively. The pro-angiogenesis factors Ets-1, CXCL1, and tissue factor were among those genes downregu-lated. SiRNA knockdown of Egr-3 markedly impaired VEGF-mediated cell migration and tube formation, as determined by in vitro wound healing, boyden chamber, and collagen gel assays. Moreover in aortic ring assays, VEGF-stimulated neo-angiogenesis from the extracted mice aorta was completely abolished by administration of adenoviral-transferred miRNA against Egr-3. Collectively, these findings suggest that NFATc and SRF cooperatively upregulate Egr-3. Egr-3 might have an important function as a signal transducer in VEGF-mediated angiogenesis in activated endothelium.


2004 ◽  
Vol 36 (12) ◽  
pp. 845-850 ◽  
Author(s):  
Wei-Hong Hou ◽  
Tian-Yun Wagn ◽  
Bao-Mei Yuan ◽  
Yu-Rong Chai ◽  
Yan-Long Jia ◽  
...  

Abstract Human canstatin, a 24 kD fragment of the α2 chain of type IV collagen, has been proved to be one of the most effective inhibitors of angiogenesis and tumor growth. To investigate in vivo antiangiogenesis activity and in vitro effects on endothelial cell proliferation of recombinant mouse canstatin, the cDNA of mouse canstatin was introduced into an expression vector pQE40 to construct a prokaryotic expression vector pQE-mCan. The recombinant mouse canstatin efficiently expressed in E. coli M15 after IPTG induction was monitored by SDS-PAGE and by Western blotting with an anti-hexahistidine tag antibody. The expressed mouse canstatin, mainly as inclusion bodies, accounted for approximately 35% of the total bacterial proteins. The inclusion bodies were washed, lysed and purified by the nickel affinity chromatography to a purity of approximately 93%. The refolded mouse canstatin was tested on the chicken embryo chorioallantoic membranes (CAM), and a large number of newly formed blood vessels were significantly regressed. In addition, recombinant mouse canstatin potently inhibited endothelial cell proliferation with no inhibition on non-endothelial cells. Taken together, these findings demonstrate that the recombinant mouse canstatin effectively inhibited angiogenesis of the chicken embryo in a dose-dependent manner and specially suppressed in vitro the proliferation of human umbilical vein endothelial cells.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 846-846
Author(s):  
Gerald W. Prager ◽  
Johannes M. Breuss4 ◽  
Patrick Brunner4 ◽  
Bernd R. Binder4

Abstract VEGF activates endothelial cells to migrate and invade surrounding tissues, an initial event in the angiogenic process. For invasion, the coordinated localized formation of a proteolytic repertoir is necessary. Focusing the urokinase receptor towards the leading edge of migrating cells provides such armor and inhibition of uPA binding to its receptor inhibits invasion of endothelial cells. In addition integrins continuously have to form focal contacts at the leading edge. Thus the spatial proximity between the localized proteases and the matrix seems to be essential for matrix degradation. In order to allow cell locomotion integrins have to release their ligands when they reach the trailing end and are subsequently endocytosed and redistributed to newly formed focal adhesions in a repetitive process. We here describe a new role of uPAR in regulating integrin redistribution. We have previously reported that stimulation of human endothelial cells by VEGF (50ng/ml) via its receptor flk-1 induces pro-uPA activation, when bound to uPAR. Subsequently a uPA/PAI-1/uPAR-complex is formed, which thereafter is endocytosed via a LDL-R family member. We now show that by this process beta-1 integrins are co-internalized in clathrin coated vesicles via a uPAR dependent mechanism. Subsequently, endocytosed uPAR recycles to focal adhesions where it co-localizes with integrin alpha-v/beta-3. Disrupting this chain of events, either by (1) RAP - a specific inhibitor of the LDL-R family - or by (2) uPAR depletion (using uPAR−/− cells or cleaving the GPI-anchor of uPAR by PI-PLC), beta-1 integrins are no longer internalized after VEGF stimulation. Under the same circumstances the migratory response of endothelial cells toward VEGF is impaired in vitro as shown by video-based migration assays and in vivo as demonstrated by matrigel angiogenesis assays. Next, we generated synthetic peptides interfering with uPAR/integrin interaction, which inhibit not only VEGF-induced integrin redistribution, but also diminish VEGF-induced endothelial cell migration, significantly. These data suggest that in VEGF-induced cell migration uPAR plays a central role not only in focusing proteolytic activity, but also in initial integrin redistribution. Interference with this process could be a therapeutic target for diseases depending on VEGF-induced angiogenesis.


Sign in / Sign up

Export Citation Format

Share Document