TY - JOUR
T1 - Nitric oxide production stimulated by the basic fibroblast growth factor requires the synthesis of ceramide
AU - Arena, Sara
AU - Pattarozzi, Alessandra
AU - Thellung, Stefano
AU - Villa, Valentina
AU - Corsaro, Alessandro
AU - Massa, Alessandro
AU - Diana, Fabrizio
AU - Spoto, Giuseppe
AU - Forcella, Sabrina
AU - Damonte, Gianluca
AU - Filocamo, Mirella
AU - Benatti, Umberto
AU - Schettini, Gennaro
AU - Florio, Tullio
PY - 2002
Y1 - 2002
N2 - Nitric oxide (NO) is an intracellular and intercellular mediator involved in the modulation of many physiologic and pathologic processes including the regulation of neoangiogenesis. We analyzed the effects of basic fibroblast growth factor (bFGF) on NO production in CHO-K1 cells and the intracellular mechanisms involved. bFGF induces NO production through activation of the endothelial NO synthase (eNOS), causing a subsequent increase in cGMP levels. In most systems, eNOS activation is a Ca2+-calmodulin-dependent process. In CHO-K1 cells, NO production by bFGF is Ca2+ and MAP kinase independent, because it was not reverted by pretreatment with intracellular Ca2+ chelators or MEK inhibitors. Translocation of the eNOS from the plasma membrane, where it is bound to caveolin 1, to the cytosol is the crucial step in the synthesis of NO. We demonstrate that the cytosolic translocation of eNOS is caused by increased synthesis of ceramide dependent by the bFGF activation of sphingomyelinase. Indeed, in the presence of the sphingomyelinase inhibitors D609 or desipramine, bFGF-dependent NO production is abrogated. To support this evidence we evaluated ceramide concentration using HPLC-electrospray ionization-mass spectrometry in controls and in bFGF-treated cells: after bFGF stimulation, a substantial increase in ceramide levels was observed. These data were further confirmed by the lack of NO production in response to fibroblast growth factor in fibroblasts derived from Niemann Pick patients who genetically lack the enzyme sphingomyelinase. In conclusion, ceramide in CHO-K1 cells is responsible for a novel Ca2+/calmodulin-independent mechanism for eNOS activation after fibroblast growth factor stimulation.
AB - Nitric oxide (NO) is an intracellular and intercellular mediator involved in the modulation of many physiologic and pathologic processes including the regulation of neoangiogenesis. We analyzed the effects of basic fibroblast growth factor (bFGF) on NO production in CHO-K1 cells and the intracellular mechanisms involved. bFGF induces NO production through activation of the endothelial NO synthase (eNOS), causing a subsequent increase in cGMP levels. In most systems, eNOS activation is a Ca2+-calmodulin-dependent process. In CHO-K1 cells, NO production by bFGF is Ca2+ and MAP kinase independent, because it was not reverted by pretreatment with intracellular Ca2+ chelators or MEK inhibitors. Translocation of the eNOS from the plasma membrane, where it is bound to caveolin 1, to the cytosol is the crucial step in the synthesis of NO. We demonstrate that the cytosolic translocation of eNOS is caused by increased synthesis of ceramide dependent by the bFGF activation of sphingomyelinase. Indeed, in the presence of the sphingomyelinase inhibitors D609 or desipramine, bFGF-dependent NO production is abrogated. To support this evidence we evaluated ceramide concentration using HPLC-electrospray ionization-mass spectrometry in controls and in bFGF-treated cells: after bFGF stimulation, a substantial increase in ceramide levels was observed. These data were further confirmed by the lack of NO production in response to fibroblast growth factor in fibroblasts derived from Niemann Pick patients who genetically lack the enzyme sphingomyelinase. In conclusion, ceramide in CHO-K1 cells is responsible for a novel Ca2+/calmodulin-independent mechanism for eNOS activation after fibroblast growth factor stimulation.
KW - bFGF
KW - Ceramide
KW - Nitric oxide
UR - http://www.scopus.com/inward/record.url?scp=0036961878&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0036961878&partnerID=8YFLogxK
M3 - Article
C2 - 12485842
AN - SCOPUS:0036961878
VL - 973
SP - 94
EP - 104
JO - Annals of the New York Academy of Sciences
JF - Annals of the New York Academy of Sciences
SN - 0077-8923
ER -