Suppression of retinal neovascularization in vivo by inhibition of vascular endothelial growth factor (VEGF) using soluble VEGF-receptor chimeric proteins.

Abstract Dipeptidyl peptidase-4 (DPP-4) inhibitors are used for the treatment of type 2 diabetes mellitus (DM). Recent studies have shown that beyond their effect in lowing glucose, DPP-4 inhibitors mitigate DM-related microvascular complications, such as diabetic retinopathy. However, the mechanism by which pathological retinal neovascularization, a major clinical manifestation of diabetic retinopathy, is inhibited is unclear. This study sought to examine the effects of evogliptin, a potent DPP-4 inhibitor, on pathological retinal neovascularization in mice and elucidate the mechanism by which evogliptin inhibits angiogenesis mediated by vascular endothelial growth factor (VEGF), a key factor in the vascular pathogenesis of proliferative diabetic retinopathy (PDR). In a murine model of PDR, an intravitreal injection of evogliptin significantly suppressed aberrant retinal neovascularization. In human endothelial cells, evogliptin reduced VEGF-induced angiogenesis. Western blot analysis showed that evogliptin inhibited the phosphorylation of signaling molecules associated with VEGF-induced cell adhesion and migration. Moreover, evogliptin substantially inhibited the VEGF-induced activation of adenosine 5′-diphosphate ribosylation factor 6 (Arf6), a small guanosine 5′-triphosphatase (GTPase) that regulates VEGF receptor 2 signal transduction. Direct activation of Arf6 using a chemical inhibitor of Arf-directed GTPase-activating protein completely abrogated the inhibitory effect of evogliptin on VEGF-induced activation of the angiogenic signaling pathway, which suggests that evogliptin suppresses VEGF-induced angiogenesis by blocking Arf6 activation. Our results provide insights into the molecular mechanism of the direct inhibitory effect of the DPP-4 inhibitor evogliptin on pathological retinal neovascularization. In addition to its glucose-lowering effect, the antiangiogenic effect of evogliptin could also render it beneficial for individuals with PDR.

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A vascular endothelial growth factor 121 (VEGF121)-based dual PET/optical probe for in vivo imaging of VEGF receptor expression

Biomaterials ◽

10.1016/j.biomaterials.2013.05.051 ◽

2013 ◽

Vol 34 (28) ◽

pp. 6839-6845 ◽

Cited By ~ 11

Author(s):

Choong Mo Kang ◽

Hyun-Jung Koo ◽

Kyo Chul Lee ◽

Yearn Seong Choe ◽

Joon Young Choi ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

In Vivo Imaging ◽

Optical Probe ◽

Receptor Expression ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Endothelial Growth Factor

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Distinct vascular endothelial growth factor signals for lymphatic vessel enlargement and sprouting

Journal of Experimental Medicine ◽

10.1084/jem.20062642 ◽

2007 ◽

Vol 204 (6) ◽

pp. 1431-1440 ◽

Cited By ~ 114

Author(s):

Maria Wirzenius ◽

Tuomas Tammela ◽

Marko Uutela ◽

Yulong He ◽

Teresa Odorisio ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Lymphatic Vessel ◽

Lymphatic Vessels ◽

Mouse Skin ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Factor C ◽

Endothelial Growth Factor

Lymphatic vessel growth, or lymphangiogenesis, is regulated by vascular endothelial growth factor-C (VEGF-C) and -D via VEGF receptor 3 (VEGFR-3). Recent studies suggest that VEGF, which does not bind to VEGFR-3, can also induce lymphangiogenesis through unknown mechanisms. To dissect the receptor pathway that triggers VEGFR-3–independent lymphangiogenesis, we used both transgenic and adenoviral overexpression of placenta growth factor (PlGF) and VEGF-E, which are specific activators of VEGFR-1 and -2, respectively. Unlike PlGF, VEGF-E induced circumferential lymphatic vessel hyperplasia, but essentially no new vessel sprouting, when transduced into mouse skin via adenoviral vectors. This effect was not inhibited by blocking VEGF-C and -D. Postnatal lymphatic hyperplasia, without increased density of lymphatic vessels, was also detected in transgenic mice expressing VEGF-E in the skin, but not in mice expressing PlGF. Surprisingly, VEGF-E induced lymphatic hyperplasia postnatally, and it did not rescue the loss of lymphatic vessels in transgenic embryos where VEGF-C and VEGF-D were blocked. Our data suggests that VEGFR-2 signals promote lymphatic vessel enlargement, but unlike in the blood vessels, are not involved in vessel sprouting to generate new lymphatic vessels in vivo.

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The soluble guanylyl cyclase inhibitor NS-2028 reduces vascular endothelial growth factor-induced angiogenesis and permeability

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00222.2009 ◽

2010 ◽

Vol 298 (3) ◽

pp. R824-R832 ◽

Cited By ~ 23

Author(s):

Lucia Morbidelli ◽

Anastasia Pyriochou ◽

Sandra Filippi ◽

Ioannis Vasileiadis ◽

Charis Roussos ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Guanylyl Cyclase ◽

Soluble Guanylyl Cyclase ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Downstream Effector ◽

Endothelial Growth Factor

Nitric oxide (NO) is known to promote vascular endothelial growth factor (VEGF)-stimulated permeability and angiogenesis. However, effector molecules that operate downstream of NO in this pathway remain poorly characterized. Herein, we determined the effect of soluble guanylyl cyclase (sGC) inhibition on VEGF responses in vitro and in vivo. Treatment of endothelial cells (EC) with VEGF stimulated eNOS phosphorylation and cGMP accumulation; pretreatment with the sGC inhibitor 4 H-8-bromo-1,2,4-oxadiazolo(3,4-d)benz(b)(1,4)oxazin-1-one (NS-2028) blunted cGMP levels without affecting VEGF-receptor phosphorylation. Incubation of cells with NS-2028 blocked the mitogenic effects of VEGF. In addition, cells in which sGC was inhibited exhibited no migration and sprouting in response to VEGF. To study the mechanisms through which NS-2028 inhibits EC migration, we determined the effects of alterations in cGMP levels on p38 MAPK. Initially, we observed that inhibition of sGC attenuated VEGF-stimulated activation of p38. In contrast, the addition of 8-Br-cGMP to EC stimulated p38 phosphorylation. The addition of cGMP elevating agents (BAY 41-2272, DETA NO and YC-1) enhanced EC migration. To test whether sGC also mediated the angiogenic effects of VEGF in vivo, we used the rabbit cornea assay. Animals receiving NS-2028 orally displayed a reduced angiogenic response to VEGF. As increased vascular permeability occurs prior to new blood vessel formation, we determined the effect of NS-2028 in vascular leakage. Using a modified Miles assay, we observed that NS-2028 attenuated VEGF-induced permeability. Overall, we provide evidence that sGC mediates the angiogenic and permeability-promoting activities of VEGF, indicating the significance of sGC as a downstream effector of VEGF-triggered responses.

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Effects of auriculasin on vascular endothelial growth factor (VEGF)-induced angiogenesis via regulation of VEGF receptor 2 signaling pathways in vitro and in vivo

Food and Chemical Toxicology ◽

10.1016/j.fct.2018.09.025 ◽

2018 ◽

Vol 121 ◽

pp. 612-621 ◽

Cited By ~ 9

Author(s):

Hyun-Dong Cho ◽

Kwang-Deog Moon ◽

Ki-Hun Park ◽

Yong-Suk Lee ◽

Kwon-Il Seo

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Signaling Pathways ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Endothelial Growth Factor

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The anti‐angiogenic vascular endothelial growth factor isoform, VEGF165b transiently increases microvascular hydraulic conductivity independently of VEGF receptor 2 signalling in vivo

The FASEB Journal ◽

10.1096/fasebj.20.4.a705-d ◽

2006 ◽

Vol 20 (4) ◽

Author(s):

Catherine Ann Glass ◽

Steven Harper ◽

David Owen Bates

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Hydraulic Conductivity ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Endothelial Growth Factor

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Extracellular RNA mediates endothelial-cell permeability via vascular endothelial growth factor

Blood ◽

10.1182/blood-2006-08-040691 ◽

2007 ◽

Vol 110 (7) ◽

pp. 2457-2465 ◽

Cited By ~ 67

Author(s):

Silvia Fischer ◽

Tibo Gerriets ◽

Carina Wessels ◽

Maureen Walberer ◽

Sawa Kostin ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

Endothelial Cells ◽

Growth Factor ◽

Brain Edema ◽

Cell Permeability ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Extracellular Rna ◽

Endothelial Growth Factor

Cell injury leads to exposure of intracellular material and is associated with increased permeability of vessels in the vicinity of the damage. Here, we demonstrate that natural extracellular RNA as well as artificial RNA (poly-I:C), or single-stranded RNA but not DNA, significantly increased the permeability across brain microvascular endothelial cells in vitro and in vivo. RNA-induced hyperpermeability of tight monolayers of endothelial cells correlated with disintegration of tight junctions and was mediated through vascular endothelial growth factor (VEGF), reminiscent of heparin's activities. Antisense oligonucleotides against VEGF-receptor 2 (VEGF-R2) prevented the permeability-inducing activity of extracellular RNA and heparin completely. Hence, these polyanionic substances can lead to mobilization/stabilization of VEGF with the subsequent activation of VEGF-R2. In accordance with these functional data, strong binding of VEGF as well as other growth factors to RNA was demonstrable. In in vivo rat models of FeCl3-induced sinus sagittal is superior thrombosis and stroke/brain edema, pretreatment of animals with RNase (but not DNase) resulted in a significant reduction of vessel occlusion, infarct volume, and prevention of brain edema formation. Together, these results identify extracellular RNA as a novel natural permeability factor, upstream of VEGF, whereas counteracting RNase treatment may serve as new vessel-protective modality.

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The splice variants of vascular endothelial growth factor (VEGF) and their receptors

Journal of Cell Science ◽

10.1242/jcs.114.5.853 ◽

2001 ◽

Vol 114 (5) ◽

pp. 853-865 ◽

Cited By ~ 16

Author(s):

C.J. Robinson ◽

S.E. Stringer

Keyword(s):

Vascular Endothelial Growth Factor ◽

Growth Factor ◽

Single Gene ◽

Heparan Sulphate ◽

Expression Patterns ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Alternative Mrna Splicing ◽

Endothelial Growth Factor

Vascular endothelial growth factor (VEGF) is a secreted mitogen highly specific for cultured endothelial cells. In vivo VEGF induces microvascular permeability and plays a central role in both angiogenesis and vasculogenesis. VEGF is a promising target for therapeutic intervention in certain pathological conditions that are angiogenesis dependent, most notably the neovascularisation of growing tumours. Through alternative mRNA splicing, a single gene gives rise to several distinct isoforms of VEGF, which differ in their expression patterns as well as their biochemical and biological properties. Two VEGF receptor tyrosine kinases (VEGFRs) have been identified, VEGFR-1 (Flt-1) and VEGFR-2 (KDR/Flk-1). VEGFR-2 seems to mediate almost all observed endothelial cell responses to VEGF, whereas roles for VEGFR-1 are more elusive. VEGFR-1 might act predominantly as a ligand-binding molecule, sequestering VEGF from VEGFR-2 signalling. Several isoform-specific VEGF receptors exist that modulate VEGF activity. Neuropilin-1 acts as a co-receptor for VEGF(165), enhancing its binding to VEGFR-2 and its bioactivity. Heparan sulphate proteoglycans (HSPGs), as well as binding certain VEGF isoforms, interact with both VEGFR-1 and VEGFR-2. HSPGs have a wide variety of functions, such as the ability to partially restore lost function to damaged VEGF(165) and thereby prolonging its biological activity.

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Effect of vascular endothelial growth factor and its receptor KDR on the transendothelial migration and local trafficking of human T cells in vitro and in vivo

Blood ◽

10.1182/blood-2009-11-252460 ◽

2010 ◽

Vol 116 (11) ◽

pp. 1980-1989 ◽

Cited By ~ 19

Author(s):

Monika Edelbauer ◽

Dipak Datta ◽

Ingrid H. C. Vos ◽

Aninda Basu ◽

Maria P. Stack ◽

...

Keyword(s):

Vascular Endothelial Growth Factor ◽

T Cells ◽

Growth Factor ◽

Cd8 T Cells ◽

Vegf Receptor ◽

Vascular Endothelial ◽

Anti Vegf ◽

Endothelial Growth Factor

Abstract In these studies, we find that the vascular endothelial growth factor (VEGF) receptor KDR is expressed on subsets of mitogen-activated CD4+ and CD8+ T cells in vitro. We also found that KDR colocalizes with CD3 on mitogen-activated T cells in vitro and on infiltrates within rejecting human allografts in vivo. To evaluate whether VEGF and KDR mediate lymphocyte migration across endothelial cells (ECs), we used an in vitro live-time transmigration model and observed that both anti-VEGF and anti-KDR antibodies inhibit the transmigration of both CD4+ and CD8+ T cells across tumor necrosis factorα (TNFα)–activated, but not unactivated ECs. In addition, we found that interactions among CD4+ or CD8+ T cells and TNFα–activated ECs result in the induction of KDR on each T cell subset, and that KDR-expressing lymphocytes preferentially transmigrate across TNFα–activated ECs. Finally, using a humanized severe combined immunodeficient mouse model of lymphocyte trafficking, we found that KDR-expressing lymphocytes migrate into human skin in vivo, and that migration is reduced in mice treated with a blocking anti-VEGF antibody. These observations demonstrate that induced expression of KDR on subsets of T cells, and locally expressed VEGF, facilitate EC-dependent lymphocyte chemotaxis, and thus, the localization of T cells at sites of inflammation.

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