Basic FGF activates phospholipase D in endothelial cells in the absence of inositol-lipid hydrolysis.
In the absence of inositol-lipid hydrolysis, mitogenic concentrations of basic fibroblast growth factor (bFGF) stimulated phosphatidylbutanol formation in the presence of butan-1-ol in [3H]myristate-labeled human umbilical vascular endothelial (HUVE) cells, indicating that the fibroblast growth factor receptor was able to couple to the activation of phospholipase D (PLD). The ability of bFGF and 12-O-tetradecanoylphorbol-13-acetate (TPA) to stimulate PLD activity was completely abolished in cells pretreated with 400 nM TPA for 48 h to downregulate protein kinase C (PKC). bFGF-stimulated PLD activity was inhibited by genistein (5 microM; P < 0.02) and the PKC inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H-7, 5 microM; P < 0.001) as well as by the removal of calcium from extracellular environment. bFGF induced DNA synthesis in a dose-dependent manner, and pretreatment of cells with H-7 inhibited the mitogenic activity of bFGF. These results indicate that activation of PKC is responsible for bFGF-induced PLD activation and the mitogenic activity of bFGF in HUVE cells. A coupled PLD/3-sn-phosphatidate phosphohydrolase pathway may play a role in the regulation of endothelial cell proliferation.
Ahmed
A
A
Department of Obstetrics and Gynecology, University of Cambridge, Rosie Maternity Hospital, United Kingdom.
Plevin
R
R
Shoaibi
M A
MA
Fountain
S A
SA
Ferriani
R A
RA
Smith
S K
SK
D002118:Calcium / Q000502:physiology; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D005110:Extracellular Space / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D019833:Genistein; D020404:Glycerophospholipids; D006801:Humans; D006868:Hydrolysis; D007294:Inositol / Q000378:metabolism; D007529:Isoflavones / Q000494:pharmacology; D050356:Lipid Metabolism; D010712:Phosphatidic Acids / Q000378:metabolism; D010739:Phospholipase D / Q000378:metabolism*; D011493:Protein Kinase C / Q000502:physiology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D020404:Glycerophospholipids; D007529:Isoflavones; D010712:Phosphatidic Acids; C068564:phosphatidylbutanol; D016222:Fibroblast Growth Factor 2; D007294:Inositol; D019833:Genistein; D011505:Protein-Tyrosine Kinases; D011493:Protein Kinase C; D010739:Phospholipase D; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium