scholarly journals VEGF tips its hand in angiogenesis

2015 ◽  
Vol 209 (4) ◽  
pp. 474-474 ◽  
Author(s):  
Ben Short

In 2003, Gerhardt et al. described how vascular endothelial growth factor guides the growth of new blood vessels.

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Hanna Lawnicka ◽  
Dorota Ptasinska-Wnuk ◽  
Slawomir Mucha ◽  
Jolanta Kunert-Radek ◽  
Marek Pawlikowski ◽  
...  

The aim of our study was to examine the involvement of renin-angiotensin system (RAS) in estrogen-induced lactotropes proliferation and vascular endothelial growth factor (VEGF) expression in rat pituitary. The study was performed on Fisher 344 rats underwent 8-day treatment with diethylstilboestrol (DES). The proliferation index (PCNA) and VEGF expression in pituitary sections were estimated using immunohistochemical methods. Treatment with DES increased the number of PCNA-positive cells, VEGF-positive cells, and VEGF-positive blood vessels in pituitary. Stimulatory effect of estrogen on cell proliferation and VEGF expression in blood vessels was attenuated by losartan, PD123319, and captopril. VEGF immunoreactivity in pituitary cells of DES-treated rats was decreased by AT1 antagonist and not changed by AT2 blocker and ACE inhibitor. Our findings suggest the involvement of RAS in DES-induced cell proliferation and VEGF expression in pituitary. Both the AT1 and AT2 receptors appear to mediate the estrogen-dependent mitogenic and proangiogenic effects in rat pituitary.


2002 ◽  
Vol 196 (11) ◽  
pp. 1497-1506 ◽  
Author(s):  
Janice A. Nagy ◽  
Eliza Vasile ◽  
Dian Feng ◽  
Christian Sundberg ◽  
Lawrence F. Brown ◽  
...  

Vascular permeability factor/vascular endothelial growth factor (VPF/VEGF, VEGF-A) is a multifunctional cytokine with important roles in pathological angiogenesis. Using an adenoviral vector engineered to express murine VEGF-A164, we previously investigated the steps and mechanisms by which this cytokine induced the formation of new blood vessels in adult immunodeficient mice and demonstrated that the newly formed blood vessels closely resembled those found in VEGF-A–expressing tumors. We now report that, in addition to inducing angiogenesis, VEGF-A164 also induces a strong lymphangiogenic response. This finding was unanticipated because lymphangiogenesis has been thought to be mediated by other members of the VPF/VEGF family, namely, VEGF-C and VEGF-D. The new “giant” lymphatics generated by VEGF-A164 were structurally and functionally abnormal: greatly enlarged with incompetent valves, sluggish flow, and delayed lymph clearance. They closely resembled the large lymphatics found in lymphangiomas/lymphatic malformations, perhaps implicating VEGF-A in the pathogenesis of these lesions. Whereas the angiogenic response was maintained only as long as VEGF-A was expressed, giant lymphatics, once formed, became VEGF-A independent and persisted indefinitely, long after VEGF-A expression ceased. These findings raise the possibility that similar, abnormal lymphatics develop in other pathologies in which VEGF-A is overexpressed, e.g., malignant tumors and chronic inflammation.


2000 ◽  
Vol 191 (10) ◽  
pp. 1789-1798 ◽  
Author(s):  
Mirna Tenan ◽  
Giulia Fulci ◽  
Michele Albertoni ◽  
Annie-Claire Diserens ◽  
Marie-France Hamou ◽  
...  

Angiogenesis, the sprouting of new capillaries from preexisting blood vessels, results from a disruption of the balance between stimulatory and inhibitory factors. Here, we show that anoxia reduces expression of thrombospondin-1 (TSP-1), a natural inhibitor of angiogenesis, in glioblastoma cells. This suggests that reduced oxygen tension can promote angiogenesis not only by stimulating the production of inducers, such as vascular endothelial growth factor, but also by reducing the production of inhibitors. This downregulation may significantly contribute to glioblastoma development, since we show that an increase in TSP-1 expression is sufficient to strongly suppress glioblastoma cell tumorigenicity in vivo.


eLife ◽  
2013 ◽  
Vol 2 ◽  
Author(s):  
Dawn Sim ◽  
Marcus Fruttiger

Researchers have identified a soluble receptor that prevents blood vessels forming in the outer retina—a process that can lead to blindness—by sequestering vascular endothelial growth factor.


2007 ◽  
Vol 19 (2) ◽  
pp. 341 ◽  
Author(s):  
Celal Kaloglu ◽  
H. Eray Bulut

Granulated metrial gland (GMG) cells are pregnancy-specific cells that may have many functions in successful placentation and pregnancy. In the present study, changes in the rat GMG cell structure, distribution and vascular endothelial growth factor (VEGF) expression during early pregnancy were evaluated by light microscopy. Implantation sites taken from females with spontaneous abortion were also investigated. On Day 7 of pregnancy, GMG cells were distributed through the implantation and interimplantation sites. They formed metrial glands in the mesometrial triangle on Day 9, and were observed in the decidua basalis on Day 14 of pregnancy. Avidin–biotin complex immunohistochemistry revealed that GMG cells showed moderate staining for VEGF at the beginning of pregnancy and intense staining on Days 9 and 10 of pregnancy. They were localised mostly near the newly formed blood vessels. The implantation sites from spontaneously aborting females showed numerous leucocytes in the lumen of mesometrial blood vessels. In spontaneously aborting females, GMG cells showed a distinct morphology, increased in number and volume, their granules were denser and degranulation was observed. These results suggest that rat GMG cells might be a guide for placental angiogenesis and they might share a role with leucocytes in pathological conditions.


2004 ◽  
Vol 106 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Marta ESCRIBANO ◽  
Laura MOLERO ◽  
Antonio LÓPEZ-FARRÉ ◽  
Cynthia ABARRATEGUI ◽  
Carolina CARRASCO ◽  
...  

Formation of blood vessels is a fundamental element in the control of tumour growth in which vascular endothelial growth factor (VEGF) and nitric oxide (NO) have been demonstrated to be involved. Our aim was to analyse whether changes in the expression of endothelial NO synthase (eNOS) and VEGF in colonic tissue could be detected early and even before the identification of colon tumour-associated morphological modifications in azoxymethane-treated rats. We studied further whether aspirin treatment changed these parameters. An increased expression of both eNOS and VEGF in colonic tissue from azoxymethane-treated rats compared with that from control rats was found. Aspirin treatment (10 mg/kg of body weight per day) reduced eNOS expression, but failed to modify the expression of VEGF in the colonic tissue of azoxymethane-treated rats. No evidence of aberrant crypt formation or changes in the number of blood vessels were observed in the colon of any of the animals studied. Expression of the VEGF receptor Flk-1, but not Flt-1, was increased in colonic tissue of azoxymethane-treated rats compared with control rats. The expression of Flk-1 was mainly localized in the epithelial cells, particularly in the lower part of the crypt. Aspirin treatment reduced Flk-1 expression in both control and azoxymethane-treated rats. Caspase-3 activity, which has been considered as an apoptotic index, was almost undetectable in azoxymethane-treated rats. Aspirin treatment stimulated caspase-3 activity. Overexpression of eNOS, VEGF and its receptor Flk-1 occurred early after azoxymethane administration in rat colonic tissue, even before morphological changes associated with tumour generation were observed, and aspirin prevented the overexpression of both eNOS and VEGF receptor Flk-1.


2007 ◽  
Vol 27 (12) ◽  
pp. 4541-4550 ◽  
Author(s):  
Koji Taniguchi ◽  
Ri-ichiro Kohno ◽  
Toranoshin Ayada ◽  
Reiko Kato ◽  
Kenji Ichiyama ◽  
...  

ABSTRACT Spred/Sprouty family proteins negatively regulate growth factor-induced ERK activation. Although the individual physiological roles of Spred-1 and Spred-2 have been investigated using gene-disrupted mice, the overlapping functions of Spred-1 and Spred-2 have not been clarified. Here, we demonstrate that the deletion of both Spred-1 and Spred-2 resulted in embryonic lethality at embryonic days 12.5 to 15.5 with marked subcutaneous hemorrhage, edema, and dilated lymphatic vessels filled with erythrocytes. This phenotype resembled that of Syk −/− and SLP-76 −/− mice with defects in the separation of lymphatic vessels from blood vessels. The number of LYVE-1-positive lymphatic vessels and lymphatic endothelial cells increased markedly in Spred-1/2-deficient embryos compared with WT embryos, while the number of blood vessels was not different. Ex vivo colony assay revealed that Spred-1/2 suppressed lymphatic endothelial cell proliferation and/or differentiation. In cultured cells, the overexpression of Spred-1 or Spred-2 strongly suppressed vascular endothelial growth factor-C (VEGF-C)/VEGF receptor (VEGFR)-3-mediated ERK activation, while Spred-1/2-deficient cells were extremely sensitive to VEGFR-3 signaling. These data suggest that Spreds play an important role in lymphatic vessel development by negatively regulating VEGF-C/VEGFR-3 signaling.


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