Lymphocytic microparticles inhibit angiogenesis by stimulating oxidative stress and negatively regulating VEGF-induced pathways

2008 ◽  
Vol 294 (2) ◽  
pp. R467-R476 ◽  
Author(s):  
Chun Yang ◽  
Bupe R. Mwaikambo ◽  
Tang Zhu ◽  
Carmen Gagnon ◽  
Josiane Lafleur ◽  
...  

Recent studies have demonstrated that lymphocyte-derived microparticles (LMPs) impair endothelial cell function. However, no data currently exist regarding the contribution of LMPs in the regulation of angiogenesis. In the present study, we investigated the effects of LMPs on angiogenesis in vivo and in vitro and demonstrated that LMPs strongly suppressed aortic ring microvessel sprouting and in vivo corneal neovascularization. In vitro, LMPs considerably diminished human umbilical vein endothelial cell survival and proliferation in a concentration-dependent manner. Mechanistically, the antioxidants U-74389G and U-83836E were partially protective against the antiproliferative effects of LMPs, whereas the NADPH oxidase (NOX) inhibitors apocynin and diphenyleneiodonium significantly abrogated these effects. Moreover, LMPs increased not only the expression of the NOX subunits gp91phox, p22phox, and p47phox, but also the production of ROS and NOX-derived superoxide (O2−). Importantly, LMPs caused a pronounced augmentation in the protein expression of the CD36 antiangiogenic receptor while significantly downregulating the protein levels of VEGF receptor type 2 and its downstream signaling mediator, phosphorylated ERK1/2. In summary, LMPs potently suppress neovascularization in vivo and in vitro by augmenting ROS generation via NOX and interfering with the VEGF signaling pathway.

Blood ◽  
2006 ◽  
Vol 107 (3) ◽  
pp. 931-939 ◽  
Author(s):  
Cassin Kimmel Williams ◽  
Ji-Liang Li ◽  
Matilde Murga ◽  
Adrian L. Harris ◽  
Giovanna Tosato

AbstractDelta-like 4 (Dll4), a membrane-bound ligand for Notch1 and Notch4, is selectively expressed in the developing endothelium and in some tumor endothelium, and it is induced by vascular endothelial growth factor (VEGF)-A and hypoxia. Gene targeting studies have shown that Dll4 is required for normal embryonic vascular remodeling, but the mechanisms underlying Dll4 regulatory functions are currently not defined. In this study, we generated primary human endothelial cells that overexpress Dll4 protein to study Dll4 function and mechanism of action. Human umbilical vein endothelial cells retrovirally transduced with Dll4 displayed reduced proliferative and migratory responses selectively to VEGF-A. Expression of VEGF receptor-2, the principal signaling receptor for VEGF-A in endothelial cells, and coreceptor neuropilin-1 was significantly decreased in Dll4-transduced endothelial cells. Consistent with Dll4 signaling through Notch, expression of HEY2, one of the transcription factors that mediates Notch function, was significantly induced in Dll4-overexpressing endothelial cells. The γ-secretase inhibitor L-685458 significantly reconstituted endothelial cell proliferation inhibited by immobilized extracellular Dll4 and reconstituted VEGFR2 expression in Dll4-overerexpressing endothelial cells. These results identify the Notch ligand Dll4 as a selective inhibitor of VEGF-A biologic activities down-regulating 2 VEGF receptors expressed on endothelial cells and raise the possibility that Dll4 may be exploited therapeutically to modulate angiogenesis.


2009 ◽  
Vol 96 (3) ◽  
pp. 682a
Author(s):  
Aydin Tay ◽  
William G. Mayhan ◽  
Denise Arrick ◽  
Chun-Hong Shao ◽  
Hong Sun ◽  
...  

2014 ◽  
Vol 9 (4) ◽  
pp. 1934578X1400900 ◽  
Author(s):  
Seon-Il Park ◽  
Toshiro Ohta ◽  
Shigenori Kumazawa ◽  
Mira Jun ◽  
Mok-Ryeon Ahn

Propolis, a sticky material that honeybees collect from living plants, has been used for its pharmaceutical properties since ancient times. In this study, we examined the effects of ethanol extracts of Korean propolis (EEKP) from various geographic regions on the inhibition of angiogenesis, both in vitro and in vivo. The effects of EEKP were tested on in vitro models of angiogenesis, that is, tube formation and proliferation of human umbilical vein endothelial cells (HUVECs). All EEKP samples exhibited significant inhibitory effects on tube formation of HUVECs in a concentration-dependent manner (6.25-25 μg/mL). In addition, two EEKP samples, prepared from Uijeongbu and Pyoseon propolis, significantly suppressed the proliferation of HUVECs in a concentration-dependent manner (3.13-25 μg/mL). Furthermore, in an in vivo angiogenesis assay using the chick embryo chorioallantoic membrane (CAM) system, we found that the two EEKP samples significantly reduced the number of newly formed vessels. These results indicate that Korean propolis may have potential applications in the prevention and treatment of angiogenesis-related diseases such as cancer.


2012 ◽  
Vol 235-236 ◽  
pp. 316-325 ◽  
Author(s):  
Le Su ◽  
Lei Han ◽  
Fei Ge ◽  
Shang Li Zhang ◽  
Yun Zhang ◽  
...  

Blood ◽  
2009 ◽  
Vol 114 (5) ◽  
pp. 1123-1130 ◽  
Author(s):  
Guo Wei ◽  
Ruchika Srinivasan ◽  
Carmen Z. Cantemir-Stone ◽  
Sudarshana M. Sharma ◽  
Ramasamy Santhanam ◽  
...  

Abstract The ras/Raf/Mek/Erk pathway plays a central role in coordinating endothelial cell activities during angiogenesis. Transcription factors Ets1 and Ets2 are targets of ras/Erk signaling pathways that have been implicated in endothelial cell function in vitro, but their precise role in vascular formation and function in vivo remains ill-defined. In this work, mutation of both Ets1 and Ets2 resulted in embryonic lethality at midgestation, with striking defects in vascular branching having been observed. The action of these factors was endothelial cell autonomous as demonstrated using Cre/loxP technology. Analysis of Ets1/Ets2 target genes in isolated embryonic endothelial cells demonstrated down-regulation of Mmp9, Bcl-XL, and cIAP2 in double mutants versus controls, and chromatin immunoprecipitation revealed that both Ets1 and Ets2 were loaded at target promoters. Consistent with these observations, endothelial cell apoptosis was significantly increased both in vivo and in vitro when both Ets1 and Ets2 were mutated. These results establish essential and overlapping functions for Ets1 and Ets2 in coordinating endothelial cell functions with survival during embryonic angiogenesis.


2013 ◽  
Author(s):  
Gareth C. Davies ◽  
James A. Harper ◽  
Richard C. Sainson ◽  
Lee Brown ◽  
Grace Opoku-Ansah ◽  
...  

2005 ◽  
Vol 11 (2) ◽  
pp. 45 ◽  
Author(s):  
L. Cannella ◽  
R. Laylor ◽  
F. Marelli-Berg ◽  
F. Dazzi

Blood ◽  
2003 ◽  
Vol 101 (8) ◽  
pp. 3014-3020 ◽  
Author(s):  
Jian-Miao Liu ◽  
Françoise Lawrence ◽  
Milica Kovacevic ◽  
Jérôme Bignon ◽  
Evangelia Papadimitriou ◽  
...  

Abstract The tetrapeptide acetyl-Ser-Asp-Lys-Pro (AcSDKP), purified from bone marrow and constitutively synthesized in vivo, belongs to the family of negative regulators of hematopoiesis. It protects the stem cell compartment from the toxicity of anticancer drugs and irradiation and consequently contributes to a reduction in marrow failure. This current work provides experimental evidence for another novel biologic function of AcSDKP. We report that AcSDKP is a mediator of angiogenesis, as measured by its ability to modulate endothelial cell function in vitro and angiogenesis in vivo. AcSDKP at nanomolar concentrations stimulates in vitro endothelial cell migration and differentiation into capillary-like structures on Matrigel as well as enhances the secretion of an active form of matrix metalloproteinase-1 (MMP-1). In vivo, AcSDKP promotes a significant angiogenic response in the chicken embryo chorioallantoic membrane (CAM) and in the abdominal muscle of the rat. Moreover, it induces the formation of blood vessels in Matrigel plugs implanted subcutaneously in the rat. This is the first report demonstrating the ability of AcSDKP to interact directly with endothelial cells and to elicit an angiogenic response in vitro and in vivo.


2016 ◽  
Vol 11 (4) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Hong-Sook Bae ◽  
Hyun Ju Kim ◽  
Da Hye Jeong ◽  
Takahiro Hosoya ◽  
Shigenori Kumazawa ◽  
...  

Crowberry, Empetrum nigrum var. japonicum, is widely used in folk medicine and grows naturally in Korea. Although some constituents and biological activity of Korean crowberry have been examined, there is little detailed information available. In this study, we investigated the effects of ethanol extracts of crowberry (EECB) on the inhibition of angiogenesis, both in vitro and in vivo. The effects of EECB were tested on in vitro models of angiogenesis, that is, tube formation and proliferation of human umbilical vein endothelial cells (HUVECs). EECB exhibited significant inhibitory effects on tube formation of HUVECs in a concentration-dependent manner. In addition, crowberry significantly suppressed the proliferation of HUVECs in a concentration-dependent manner. Furthermore, strong antiangiogenic activity of EECB samples was observed in the in vivo assay using chick embryo chorioallantoic membrane (CAM). These results indicate that crowberry may have potential applications in the prevention and treatment of angiogenesis-dependent human diseases.


Blood ◽  
1997 ◽  
Vol 90 (9) ◽  
pp. 3595-3602 ◽  
Author(s):  
Jiafan Qi ◽  
Sandra Goralnick ◽  
Donald L. Kreutzer

Abstract Recent studies in our laboratory, as well as others, have suggested that fibrin can regulate cell function in vitro and likely control inflammation in vivo by acting as a potent cell activator. This has led us to hypothesize that during tissue and vascular injury, fibrin can enhance leukocyte recruitment by inducing vascular endothelial cell expression of leukocyte chemotactic factors. To begin to test this hypothesis, we developed an in vitro model of in situ fibrin polymerization on human umbilical vein endothelial cell culture (HUVEC) and determined the ability of fibrin to induce HUVEC expression of the potent leukocyte chemotactic factor interleukin-8 (IL-8). Our initial studies showed that fibrin induced IL-8 expression in a time- and dose-dependent fashion. Fibrin-induced IL-8 expression in HUVEC could be seen as early as 2 hours post-fibrin stimulation. Additionally, fibrin concentrations as low as 30 μg/mL stimulated a detectable level of IL-8 antigen expression from HUVEC. We also showed that this fibrin induced IL-8 had the identical molecular weight and similar antigenic identity as recombinant and monocyte derived IL-8. Northern blot analysis showed that the IL-8 antigen increase seen in fibrin treated HUVEC was due to fibrin induced elevation of steady state mRNA expression in HUVEC. These data clearly support our hypothesis that fibrin is a potent vascular endothelial cell (VEC) activator that can directly contribute to leukocyte recruitment and activation by inducing leukocyte chemotactic factor expression from VEC.


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