Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Vascular endothelial growth factor-A signaling in bone marrow-derived endothelial progenitor cells exposed to hypoxic stress. Physiol Genomics 2013 Nov 01;45(21):1021-34 PMID: 24022223 PMCID: PMC3841787

Abstract

Bone marrow-derived endothelial progenitor cells (BM-EPCs) are stimulated by vascular endothelial growth factor-A (VEGF-A) and other potent proangiogenic factors. During angiogenesis, an increase in VEGF-A expression stimulates BM-EPCs to enhance endothelial tube formation and contribute to an increase in microvessel density. Hypoxia is known to produce an enhanced angiogenic response and heightened levels of VEGF-A have been seen in oxygen deprived epithelial and endothelial cells, yet the pathways for VEGF-A signaling in BM-EPCs have not been described. This study explores the influence of hypoxia on VEGF-A signaling in rat BM-EPCs utilizing a novel proteomic strategy to directly identify interacting downstream components of the combined VEGF receptor(s) signaling pathways, gene expression analysis, and functional phenotyping. VEGF-A signaling network analysis following liquid chromatographic separation and tandem mass spectrometry revealed proteins related to inositol/calcium signaling, nitric oxide signaling, cell survival, cell migration, and inflammatory responses. Alterations in BM-EPC expression of common angiogenic genes and tube formation in response to VEGF-A during hypoxia were measured and combined with the proteomic analysis to enhance and support the signaling pathways detected. BM-EPC tube formation assays in response to VEGF-A exhibited little tube formation; however, a cell projection/migratory phenotype supported the signaling data. Additionally, a novel assay measuring BM-EPC incorporation into preformed endothelial cell tubes indicated a significant increase of incorporated BM-EPCs after pretreatment with VEGF-A during hypoxia. This study verifies known VEGF-A pathway components and reveals several unidentified mechanisms of VEGF-A signaling in BM-EPCs during hypoxia that may be important for migration to sites of vascular regeneration.

Author List

Hoffmann BR, Wagner JR, Prisco AR, Janiak A, Greene AS

Authors

Andrew S. Greene PhD Interim Vice Chair, Chief, Professor in the Biomedical Engineering department at Medical College of Wisconsin
Brian R. Hoffmann PhD Assistant Professor in the Biomedical Engineering department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Bone Marrow Cells
Cell Hypoxia
Cell Movement
Cell Survival
Cells, Cultured
Chromatography, High Pressure Liquid
Endothelial Cells
Gene Expression Regulation
Mass Spectrometry
Models, Genetic
Neovascularization, Physiologic
Peptide Fragments
Proteomics
Rats
Rats, Sprague-Dawley
Reverse Transcriptase Polymerase Chain Reaction
Signal Transduction
Stem Cells
Vascular Endothelial Growth Factor A
Vascular Endothelial Growth Factor Receptor-2



View this publication's entry at the Pubmed website PMID: 24022223
jenkins-FCD Prod-158 788e756cee95f97989f23472575fc754037544be