Mechanical endothelial damage results in basic fibroblast growth factor-mediated activation of extracellular signal-regulated kinases.
BACKGROUND
Endothelial damage, such as that associated with balloon angioplasty or preparation of veins for bypass grafts, results in intimal hyperplasia. Growth factors and cytokines that modulate endothelial cell functions through various intracellular signaling pathways mediate rapid endothelial repair, which may prevent or reduce restenosis. Here we investigated the effect of mechanical injury of endothelial cells on the mitogen-activated kinase signaling pathways, extracellular-signal-regulated kinases (ERKs), C-Jun N-terminal kinase (JNK/SAPK), and p38.


METHODS
Confluent human umbilical vein endothelial cells or bovine aortic endothelial cells were wounded with a razor blade; mitogen-activated kinase activation was monitored by immunoblotting with antibodies to active ERK, JNK/SAPK, or p38.


RESULTS
Wounding of human umbilical vein endothelial cell or bovine aortic endothelial cell monolayers resulted in rapid (5-minute) activation of ERK-1 and -2, which was abolished by monoclonal antibody to basic fibroblast growth factor (FGF-2). This antibody or an inhibitor of ERK activation, PD98059, also blocked endothelial cell migration after the wounding. Thus FGF-2-induced ERK activation mediates the endothelial response to wounding.


CONCLUSIONS
ERK-1 and -2 are activated by FGF-2 released from endothelial cells in response to injury. Therapeutic strategies aimed at reducing FGF-2-induced intimal hyperplasia should preserve ERK activation in endothelial cells while abolishing it in smooth muscle cells.
Pintucci
G
G
Department of Surgery, New York University School of Medicine, New York, USA.
Steinberg
B M
BM
Seghezzi
G
G
Yun
J
J
Apazidis
A
A
Baumann
F G
FG
Grossi
E A
EA
Colvin
S B
SB
Mignatti
P
P
Galloway
A C
AC
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000502:physiology*; D002417:Cattle; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000502:physiology*; D004789:Enzyme Activation; D016222:Fibroblast Growth Factor 2 / Q000502:physiology*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D019950:Mitogen-Activated Protein Kinase 1 / Q000502:physiology*; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D011494:Protein Kinases / Q000502:physiology; D048051:p38 Mitogen-Activated Protein Kinases
D016222:Fibroblast Growth Factor 2; D011494:Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D020929:Mitogen-Activated Protein Kinase Kinases