Browse
Submit Data
Databases
API
Help

Dataset Information

16 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Platelet Factor 4 Binds to Vascular Proteoglycans and Controls Both Growth Factor Activities and Platelet Activation.

ABSTRACT: Platelet factor 4 (PF4) is produced by platelets with roles in both inflammation and wound healing. PF4 is stored in platelet ?-granules bound to the glycosaminoglycan (GAG) chains of serglycin. This study revealed that platelet serglycin is decorated with chondroitin/dermatan sulfate and that PF4 binds to these GAG chains. Additionally, PF4 had a higher affinity for endothelial-derived perlecan heparan sulfate chains than serglycin GAG chains. The binding of PF4 to perlecan was found to inhibit both FGF2 signaling and platelet activation. This study revealed additional insight into the ways in which PF4 interacts with components of the vasculature to modulate cellular events.

SUBMITTER: Lord MS

PROVIDER: S-EPMC5354495 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Platelet Factor 4 Binds to Vascular Proteoglycans and Controls Both Growth Factor Activities and Platelet Activation.

Lord Megan S MS Cheng Bill B Farrugia Brooke L BL McCarthy Simon S Whitelock John M JM

The Journal of biological chemistry 20170123 10

Platelet factor 4 (PF4) is produced by platelets with roles in both inflammation and wound healing. PF4 is stored in platelet α-granules bound to the glycosaminoglycan (GAG) chains of serglycin. This study revealed that platelet serglycin is decorated with chondroitin/dermatan sulfate and that PF4 binds to these GAG chains. Additionally, PF4 had a higher affinity for endothelial-derived perlecan heparan sulfate chains than serglycin GAG chains. The binding of PF4 to perlecan was found to inhibit ...[more]

PMID: 28115521

Similar Datasets

Vascular endothelial growth factor can signal through platelet-derived growth factor receptors.

Project description:Vascular endothelial growth factor (VEGF-A) is a crucial stimulator of vascular cell migration and proliferation. Using bone marrow-derived human adult mesenchymal stem cells (MSCs) that did not express VEGF receptors, we provide evidence that VEGF-A can stimulate platelet-derived growth factor receptors (PDGFRs), thereby regulating MSC migration and proliferation. VEGF-A binds to both PDGFRalpha and PDGFRbeta and induces tyrosine phosphorylation that, when inhibited, results in attenuation of VEGF-A-induced MSC migration and proliferation. This mechanism was also shown to mediate human dermal fibroblast (HDF) migration. VEGF-A/PDGFR signaling has the potential to regulate vascular cell recruitment and proliferation during tissue regeneration and disease.

| S-EPMC2064818 | biostudies-literature

Autocrine platelet-derived growth factor-vascular endothelial growth factor receptor-related (Pvr) pathway activity controls intestinal stem cell proliferation in the adult Drosophila midgut.

Project description:A dynamic pool of undifferentiated somatic stem cells proliferate and differentiate to replace dead or dying mature cell types and maintain the integrity and function of adult tissues. Intestinal stem cells (ISCs) in the Drosophila posterior midgut are a well established model to study the complex genetic circuitry that governs stem cell homeostasis. Exposure of the intestinal epithelium to environmental toxins results in the expression of cytokines and growth factors that drive the rapid proliferation and differentiation of ISCs. In the absence of stress signals, ISC homeostasis is maintained through intrinsic pathways. In this study, we uncovered the PDGF- and VEGF-receptor related (Pvr) pathway as an essential regulator of ISC homeostasis under unstressed conditions in the posterior midgut. We found that Pvr is coexpressed with its ligand Pvf2 in ISCs and that hyperactivation of the Pvr pathway distorts the ISC developmental program and drives intestinal dysplasia. In contrast, we show that mutant ISCs in the Pvf/Pvr pathway are defective in homeostatic proliferation and differentiation, resulting in a failure to generate mature cell types. Additionally, we determined that extrinsic stress signals generated by enteropathogenic infection are epistatic to the hypoplasia generated in Pvf/Pvr mutants, making the Pvr pathway unique among all previously studied intrinsic pathways. Our findings illuminate an evolutionarily conserved signal transduction pathway with essential roles in metazoan embryonic development and direct involvement in numerous disease states.

| S-EPMC3431626 | biostudies-literature

Vascular endothelial growth factor receptor 3 controls neural stem cell activation in mice and humans.

Project description:Neural stem cells (NSCs) continuously produce new neurons within the adult mammalian hippocampus. NSCs are typically quiescent but activated to self-renew or differentiate into neural progenitor cells. The molecular mechanisms of NSC activation remain poorly understood. Here, we show that adult hippocampal NSCs express vascular endothelial growth factor receptor (VEGFR) 3 and its ligand VEGF-C, which activates quiescent NSCs to enter the cell cycle and generate progenitor cells. Hippocampal NSC activation and neurogenesis are impaired by conditional deletion of Vegfr3 in NSCs. Functionally, this is associated with compromised NSC activation in response to VEGF-C and physical activity. In NSCs derived from human embryonic stem cells (hESCs), VEGF-C/VEGFR3 mediates intracellular activation of AKT and ERK pathways that control cell fate and proliferation. These findings identify VEGF-C/VEGFR3 signaling as a specific regulator of NSC activation and neurogenesis in mammals.

| S-EPMC4685253 | biostudies-literature

Vascular endothelial growth factor A competitively inhibits platelet-derived growth factor (PDGF)-dependent activation of PDGF receptor and subsequent signaling events and cellular responses.

Project description:Certain platelet-derived growth factor (PDGF) isoforms are associated with proliferative vitreoretinopathy (PVR), a sight-threatening complication that develops in a subset of patients recovering from retinal reattachment surgery. Although these PDGF isoforms are abundant in the vitreous of patients and experimental animals with PVR, they make only a minor contribution to activating PDGF receptor ? (PDGFR?) and driving experimental PVR. Rather, growth factors outside of the PDGF family are the primary (and indirect) agonists of PDGFR?. These observations beg the question of why vitreal PDGFs fail to activate PDGFR?. We report here that vitreous contains an inhibitor of PDGF-dependent activation of PDGFR? and that a major portion of this inhibitory activity is due to vascular endothelial cell growth factor A (VEGF-A). Furthermore, recombinant VEGF-A competitively blocks PDGF-dependent binding and activation of PDGFR, signaling events, and cellular responses. These findings unveil a previously unappreciated relationship between distant members of the PDGF/VEGF family that may contribute to pathogenesis of a blinding eye disease.

| S-EPMC3347401 | biostudies-literature

Vascular endothelial growth factor signals through platelet-derived growth factor receptor β in meningiomas in vitro.

Project description:BackgroundVascular endothelial growth factor (VEGF)-mediated angiogenesis mediates tumour growth and metastasis. Meningiomas are primarily benign, slow-growing, highly vascularised tumours. Aside from VEGF, there is little data on the function of major angiogenic proteins in meningiomas.MethodsThe VEGFA, platelet-derived growth factor B (PDGFB), and their respective receptors - VEGF receptor 2 (KDR) and PDGF receptor β (PDGFRβ) - were quantified using real-time PCR and a TaqMan Protein Assay in meningiomas in vivo and in vitro. The effect of VEGFA and PDGFB on cell proliferation and the tyrosine phosphorylation of PDGFRβ were examined.ResultsMost meningiomas displayed no KDR protein expression but elevated PDGFRβ levels. Exogenous VEGFA stimulation significantly increased cell proliferation. The PDGFRβ inhibition before stimulation with VEGFA abolished the proliferative stimuli. The VEGFA induced concentration-dependent PDGFRβ tyrosine phosphorylation comparable to PDGFB-induced PDGFRβ tyrosine phosphorylation. The PDGFRβ inhibitors gambogic acid, sunitinib, and tandutinib equally impaired the migration of meningioma cells. In addition, gambogic acid suppressed the VEGFA-induced PDGFRβ tyrosine phosphorylation.ConclusionCollectively, our data suggest that VEGFA primarily regulates VEGF-mediated migration through PDGFRβ in meningiomas. The inhibitory effect of gambogic acid and tandutinib against meningioma growth in vitro suggests that selective PDGFRβ inhibitors, in combination with VEGF inhibitors, should be evaluated further as potential therapies for recurrent and malignant meningiomas.

| S-EPMC3493872 | biostudies-literature

Vascular endothelial growth factor acts primarily via platelet-derived growth factor receptor α to promote proliferative vitreoretinopathy.

Project description:Proliferative vitreoretinopathy (PVR) is a nonneovascular blinding disease and the leading cause for failure in surgical repair of rhegmatogenous retinal detachments. Once formed, PVR is difficult to treat. Hence, there is an acute interest in developing approaches to prevent PVR. Of the many growth factors and cytokines that accumulate in vitreous as PVR develops, neutralizing vascular endothelial growth factor (VEGF) A has recently been found to prevent PVR in at least one animal model. The goal of this study was to test if Food and Drug Administration-approved agents could protect the eye from PVR in multiple animal models and to further investigate the underlying mechanisms. Neutralizing VEGF with aflibercept (VEGF Trap-Eye) safely and effectively protected rabbits from PVR in multiple models of disease. Furthermore, aflibercept reduced the bioactivity of both experimental and clinical PVR vitreous. Finally, although VEGF could promote some PVR-associated cellular responses via VEGF receptors expressed on the retinal pigment epithelial cells that drive this disease, VEGF's major contribution to vitreal bioactivity occurred via platelet-derived growth factor receptor α. Thus, VEGF promotes PVR by a noncanonical ability to engage platelet-derived growth factor receptor α. These findings indicate that VEGF contributes to nonangiogenic diseases and that anti-VEGF-based therapies may be effective on a wider spectrum of diseases than previously appreciated.

| S-EPMC4215028 | biostudies-literature

Mice Lacking Platelet-Derived Growth Factor D Display a Mild Vascular Phenotype.

Project description:Platelet-derived growth factor D (PDGF-D) is the most recently discovered member of the PDGF family. PDGF-D signals through PDGF receptor ?, but its biological role remains largely unknown. In contrast to other members of the PDGF family of growth factors, which have been extensively investigated using different knockout approaches in mice, PDGF-D has until now not been characterized by gene inactivation in mice. Here, we present the phenotype of a constitutive Pdgfd knockout mouse model (Pdgfd-/-), carrying a LacZ reporter used to visualize Pdgfd promoter activity. Inactivation of the Pdgfd gene resulted in a mild phenotype in C57BL/6 mice, and the offspring was viable, fertile and generally in good health. We show that Pdgfd reporter gene activity was consistently localized to vascular structures in both postnatal and adult tissues. The expression was predominantly arterial, often localizing to vascular bifurcations. Endothelial cells appeared to be the dominating source for Pdgfd, but reporter gene activity was occasionally also found in subpopulations of mural cells. Tissue-specific analyses of vascular structures revealed that NG2-expressing pericytes of the cardiac vasculature were disorganized in Pdgfd-/- mice. Furthermore, Pdgfd-/- mice also had a slightly elevated blood pressure. In summary, the vascular expression pattern together with morphological changes in NG2-expressing cells, and the increase in blood pressure, support a function for PDGF-D in regulating systemic arterial blood pressure, and suggests a role in maintaining vascular homeostasis.

| S-EPMC4816573 | biostudies-literature

The vascular niche controls Drosophila hematopoiesis via fibroblast growth factor signaling.

Project description:In adult mammals, hematopoiesis, the production of blood cells from hematopoietic stem and progenitor cells (HSPCs), is tightly regulated by extrinsic signals from the microenvironment called 'niche'. Bone marrow HSPCs are heterogeneous and controlled by both endosteal and vascular niches. The Drosophila hematopoietic lymph gland is located along the cardiac tube which corresponds to the vascular system. In the lymph gland, the niche called Posterior Signaling Center controls only a subset of the heterogeneous hematopoietic progenitor population indicating that additional signals are necessary. Here we report that the vascular system acts as a second niche to control lymph gland homeostasis. The FGF ligand Branchless produced by vascular cells activates the FGF pathway in hematopoietic progenitors. By regulating intracellular calcium levels, FGF signaling maintains progenitor pools and prevents blood cell differentiation. This study reveals that two niches contribute to the control ofDrosophila blood cell homeostasis through their differential regulation of progenitors.

| S-EPMC7781598 | biostudies-literature

Nuclear receptor COUP-TFII controls pancreatic islet tumor angiogenesis by regulating vascular endothelial growth factor/vascular endothelial growth factor receptor-2 signaling.

Project description:The significance of angiogenesis in cancer biology and therapy is well established. In this study, we used the prototypical RIP-Tag model of multistage pancreatic islet tumorigenesis to show that the nuclear receptor COUP-TFII is essential to regulate the balance between pro- and anti-angiogenic molecules that influence the angiogenic switch in cancer. Conditional ablation of COUP-TFII in the tumor microenvironment severely compromised neoangiogenesis and lymphangiogenesis during pancreatic tumor progression and metastasis. We found that COUP-TFII plays a cell-autonomous role in endothelial cells to control blood vessel sprouting by regulating cell proliferation and migration. Mechanistic investigations revealed that COUP-TFII suppressed vascular endothelial growth factor (VEGF)/VEGF receptor-2 (VEGFR-2) signaling by transcriptionally repressing the expression of VEGFR-1, thereby curtailing a central angiogenic driver of vascular growth. Taken together, our results implicate COUP-TFII as a critical factor in tumor angiogenesis through regulation of VEGF/VEGFR-2 signaling, suggesting COUP-TFII as a candidate target for antiangiogenic therapy.

| S-EPMC2970665 | biostudies-literature

Vascular Endothelial Cell Growth Factor A Acts via Platelet-Derived Growth Factor Receptor ? To Promote Viability of Cells Enduring Hypoxia.

Project description:Vascular endothelial cell growth factor A (VEGF) is a biologically and therapeutically important growth factor because it promotes angiogenesis in response to hypoxia, which underlies a wide variety of both physiological and pathological settings. We report here that both VEGF receptor 2 (VEGFR2)-positive and -negative cells depended on VEGF to endure hypoxia. VEGF enhanced the viability of platelet-derived growth factor receptor ? (PDGFR?)-positive and VEGFR2-negative cells by enabling indirect activation of PDGFR?, thereby reducing the level of p53. We conclude that the breadth of VEGF's influence extends beyond VEGFR-positive cells and propose a plausible mechanistic explanation of this phenomenon.

| S-EPMC5007796 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data