Vascular endothelial growth factor-induced secretion of fibronectin is ERK dependent.
In severe asthma, cytokines and growth factors contribute to the proliferation of smooth muscle cells and blood vessels, and to the increased extracellular matrix deposition that constitutes the process of airway remodeling. Vascular endothelial growth factor (VEGF), which regulates vascular permeability and angiogenesis, also modulates the function of nonendothelial cell types. In this study, we demonstrate that VEGF induces fibronectin secretion by human airway smooth muscle (ASM) cells. In addition, stimulation of ASM with VEGF activates ERK, but not p38MAPK, and fibronectin secretion is ERK dependent. Both ERK activation and fibronectin secretion appear to be mediated through the VEGF receptor flt-1, as evidenced by the effects of the flt-1-specific ligand placenta growth factor. Finally, we demonstrate that ASM cells constitutively secrete VEGF, which is increased in response to PDGF, transforming growth factor-beta, IL-1beta, and PGE(2). We conclude that ASM-derived VEGF, through modulation of the extracellular matrix, may play an important role in airway remodeling seen in asthma.
Kazi
Altaf S
AS
Pulmonary, Allergy, and Critical Care Division, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
Lotfi
Shidan
S
Goncharova
Elena A
EA
Tliba
Omar
O
Amrani
Yassine
Y
Krymskaya
Vera P
VP
Lazaar
Aili L
AL
D001249:Asthma / Q000378:metabolism / Q000503:physiopathology; D019898:Autocrine Communication / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D002478:Cells, Cultured; D004789:Enzyme Activation / Q000502:physiology; D016326:Extracellular Matrix Proteins / Q000235:genetics; D005353:Fibronectins / Q000378:metabolism*; D006801:Humans; D020935:MAP Kinase Signaling System / Q000502:physiology; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009130:Muscle, Smooth / Q000166:cytology / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism / Q000502:physiology; D040262:Receptors, Vascular Endothelial Growth Factor / Q000235:genetics; D014132:Trachea / Q000166:cytology / Q000378:metabolism*; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics*; D040281:Vascular Endothelial Growth Factor Receptor-1
D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D042461:Vascular Endothelial Growth Factor A; C501162:FLT1 protein, human; D040262:Receptors, Vascular Endothelial Growth Factor; D040281:Vascular Endothelial Growth Factor Receptor-1; D020928:Mitogen-Activated Protein Kinases