scholarly journals An unexpected tail of VEGF and PlGF in pre-eclampsia

2011 ◽  
Vol 39 (6) ◽  
pp. 1576-1582 ◽  
Author(s):  
David O. Bates
Keyword(s):  
Endothelial Cells ◽  
Growth Factor ◽  
Endothelial Activation ◽  
Placental Growth Factor ◽  
Vegf Receptor ◽  
Vascular Endothelial ◽  
Physiological Changes ◽  
Vegf Family Members ◽  
Endothelial Growth Factor ◽  
Vegf Isoforms

PET (pre-eclamptic toxaemia), characterized by pregnancy-related hypertension and proteinuria, due to widespread endothelial dysfunction, is a primary cause of maternal morbidity. Altered circulating factors, particularly the VEGF (vascular endothelial growth factor) family of proteins and their receptors, are thought to be key contributors to this disease. Plasma from patients with PET induces numerous cellular and physiological changes in endothelial cells, indicating the presence of a circulating imbalance of the normal plasma constituents. These have been narrowed down to macromolecules of the VEGF family of proteins and receptors. It has been shown that responses of endothelial cells in intact vessels to plasma from patients with pre-eclampsia is VEGF-dependent. It has recently been shown that this may be specific to the VEGF165b isoform, and blocked by addition of recombinant human PlGF (placental growth factor). Taken together with results that show that sVEGFR1 (soluble VEGF receptor 1) levels are insufficient to bind VEGF-A in human plasma from patients with pre-eclampsia, and that other circulating macromolecules bind, but do not inactivate, VEGF-A, this suggests that novel hypotheses involving altered bioavailability of VEGF isoforms resulting from reduced or bound PlGF, or increased sVEGFR1 increasing biological activity of circulating plasma, could be tested. This suggests that knowing how to alter the balance of VEGF family members could prevent endothelial activation, and potentially some symptoms, of pre-eclampsia.

Model of competitive binding of vascular endothelial growth factor and placental growth factor to VEGF receptors on endothelial cells

2004 ◽  
Vol 286 (1) ◽  
pp. H153-H164 ◽  
Author(s):  
Feilim Mac Gabhann ◽  
Aleksander S. Popel
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Endothelial Cells ◽  
Growth Factor ◽  
Synergistic Effects ◽  
Placental Growth Factor ◽  
Vegf Receptor ◽  
Vascular Endothelial ◽  
Relative Contribution ◽  
Endothelial Growth Factor

Placental growth factor (PlGF) competes with vascular endothelial growth factor (VEGF) for binding to VEGF receptor (VEGFR)-1 but does not bind VEGFR2. Experiments show that PlGF can augment the response to VEGF in pathological angiogenesis and in models of endothelial cell survival, migration, and proliferation. This synergy has been hypothesized to be due to a combination of the following: signaling by PlGF through VEGFR1 and displacement of VEGF from VEGFR1 to VEGFR2 by PlGF, causing increased signaling through VEGFR2. In this study, the relative contribution of PlGF-induced VEGF displacement to the synergy is quantified using a mathematical model of ligand-receptor binding to examine the effect on ligand-receptor complex formation of VEGF and PlGF acting together. Parameters specific to the VEGF-PlGF system are used based on existing data. The model is used to simulate in silico a specific in vitro experiment in which VEGF-PlGF synergy is observed. We show that, whereas a significant change in the formation of endothelial surface growth factor-VEGFR1 complexes is predicted in the presence of PlGF, the increase in the number of VEGFR2-containing signaling complexes is less significant; these results were shown to be robust to significant variation in the kinetic parameters of the model. Synergistic effects observed in that experiment thus appear unlikely to be due to VEGF displacement but to a shift from VEGF-VEGFR1 to PlGF-VEGFR1 complexes and an increase in total VEGFR1 complexes. These results suggest that VEGFR1 signaling can be functional in adult-derived endothelial cells.

scholarly journals Receptors of vascular endothelial growth factor/vascular permeability factor (VEGF/VPF) in fetal and adult human kidney: localization and [125I]VEGF binding sites.

1998 ◽  
Vol 9 (6) ◽  
pp. 1032-1044 ◽  
Author(s):  
M Simon ◽  
W Röckl ◽  
C Hornig ◽  
E F Gröne ◽  
H Theis ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Endothelial Cells ◽  
Growth Factor ◽  
Binding Sites ◽  
Vegf Receptor ◽  
Vascular Endothelial ◽  
Placenta Growth Factor ◽  
Receptor Proteins ◽  
Adult Kidney ◽  
Endothelial Growth Factor

Vascular endothelial growth factor (VEGF) has an important function in renal vascular ontogenesis and is constitutively expressed in podocytes of the adult kidney. The ability of VEGF to be chemotactic for monocytes and to increase the activity of collagenase and plasminogen activator may have implications for renal development and renal disease. In humans, the cellular actions of VEGF depend on binding to two specific receptors: Flt-1 and KDR. The aims of this study were: (1) to localize VEGF receptor proteins in human renal ontogenesis; (2) to quantify VEGF binding in human fetal and adult kidney; and (3) to dissect the binding into its two known components: the KDR and Flt-1 receptors. The latter aim was achieved by competitive binding of VEGF and placenta growth factor-2, which only binds to Flt-1. Quantification of 125I-VEGF binding sites was performed by autoradiography and computerized densitometry. By double-label immunohistochemistry, VEGF receptor proteins were localized solely to endothelial cells of preglomerular vessels, glomeruli, and postglomerular vessels. In developing glomeruli, VEGF receptor protein appeared as soon as endothelial cells were positive for von Willebrand factor. Specific 125I-VEGF binding could be localized to renal arteries and veins, glomeruli, and the tubulointerstitial capillary network in different developmental stages. Affinity (Kd) of adult (aK) and fetal (fK) kidneys was: Kd: glomeruli 38.6 +/- 11.2 (aK, n = 5), 36.3 +/- 7.1 (fK, n = 5); cortical tubulointerstitium 19.4 +/- 2.6 (aK, n = 5), 11.6 +/- 7.0 (fK, n = 5) pmol. Placenta growth factor-2 displaced VEGF binding in all renal structures by approximately 60%. VEGF receptor proteins thus were found only in renal endothelial cells. A coexpression of both VEGF binding sites could be shown, with Flt-1 demonstrating the most abundant VEGF receptor binding sites in the kidney. These studies support the hypothesis of a function for VEGF in adult kidney that is independent of angiogenesis.

Neuropilin-1 regulates attachment in human endothelial cells independently of vascular endothelial growth factor receptor-2

Blood ◽  
2005 ◽  
Vol 105 (5) ◽  
pp. 1992-1999 ◽  
Author(s):  
Matilde Murga ◽  
Oscar Fernandez-Capetillo ◽  
Giovanna Tosato
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Endothelial Cells ◽  
Endothelial Cell ◽  
Growth Factor ◽  
Critical Role ◽  
Vegf Receptor ◽  
Vascular Endothelial ◽  
Human Endothelial Cells ◽  
Neuropilin 1 ◽  
Endothelial Growth Factor

AbstractNeuropilin-1 (NRP-1) is a type 1 membrane protein that binds the axon guidance factors belonging to the class-3 semaforin family. In endothelial cells, NRP-1 serves as a co-receptor for vascular endothelial growth factor (VEGF) and regulates VEGF receptor 2 (VEGFR-2)–dependent angiogenesis. Although gene-targeting studies documenting embryonic lethality in NRP-1 null mice have demonstrated a critical role for NRP-1 in vascular development, the activities of NRP-1 in mature endothelial cells have been incompletely defined. Using RNA interference-mediated silencing of NRP-1 or VEGFR-2 in primary human endothelial cells, we confirm that NRP-1 modulates VEGFR-2 signaling-dependent mitogenic functions of VEGF. Importantly, we now show that NRP-1 regulates endothelial cell adhesion to extracellular matrix proteins independently of VEGFR-2. Based on its dual role as an enhancer of VEGF activity and a mediator of endothelial cell adhesiveness described here, NRP-1 emerges as a promising molecular target for the development of antiangiogenic drugs.

scholarly journals Vascular Pool of Releasable Soluble VEGF Receptor-1 (sFLT1) in Women With Previous Preeclampsia and Uncomplicated Pregnancy

2014 ◽  
Vol 99 (3) ◽  
pp. 978-987 ◽  
Author(s):  
Tracey L. Weissgerber ◽  
Augustine Rajakumar ◽  
Ashley C. Myerski ◽  
Lia R. Edmunds ◽  
Robert W. Powers ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Growth Factor ◽  
Whole Blood ◽  
Placental Growth Factor ◽  
Potential Contribution ◽  
Vegf Receptor ◽  
Vascular Endothelial ◽  
Uncomplicated Pregnancy ◽  
Heparin Plasma ◽  
Endothelial Growth Factor

Context: Research examining the source of excess soluble fms-like tyrosine kinase 1 (sFLT1) in preeclampsia has focused on the placenta. The potential contribution of the releasable store of sFLT1 in the systemic vasculature is unknown. Objective: We asked whether the nonplacental releasable store of sFLT1 is larger in women with previous preeclampsia than in women with a previous uncomplicated pregnancy. Design: We administered heparin to nulligravid women and to women with previous preeclampsia or a previous uncomplicated pregnancy. We compared post-heparin sFLT1 concentrations with those observed in uncomplicated pregnancy and preeclampsia. Setting: The study was performed at Magee-Womens Hospital. Patients: Participants included nulligravidas (n = 8), women 6–24 months postpartum (previous uncomplicated pregnancy, n = 16; previous preeclampsia, n = 15), and pregnant women (uncomplicated pregnancy, n = 30; preeclampsia, n = 25). Intervention: Nonpregnant women received an unfractionated heparin bolus. Main Outcome Measures: Pre- and post-heparin plasma sFLT1, placental growth factor, and vascular endothelial growth factor were measured. Results: In nonpregnant women, heparin increased plasma sFLT1 by 250-fold (P < .01), increased placental growth factor by 7-fold (P < .01), and decreased free vascular endothelial growth factor (P < .01). These changes did not differ between nulligravidas, women with previous preeclampsia, and women with a previous uncomplicated pregnancy. Post-heparin sFLT1 in nonpregnant women was higher than sFLT1 in uncomplicated pregnancy, but lower than sFLT1 in preeclampsia. Baseline and post-heparin sFLT1 were positively correlated (r2 = 0.19; P < .01). Heparin increased the concentration of the 100-kDa sFLT1 isoform. Adding heparin to whole blood or plasma did not increase sFLT1. Conclusions: Nonpregnant women have a significant vascular store of releasable sFLT1. The size of this store does not differ between women with previous preeclampsia vs women with previous uncomplicated pregnancy.

Sign in / Sign up

Export Citation Format

Share Document