Cytochrome P450 2C9-induced endothelial cell proliferation involves induction of mitogen-activated protein (MAP) kinase phosphatase-1, inhibition of the c-Jun N-terminal kinase, and up-regulation of cyclin D1.
Cytochrome P450 (CYP)-derived epoxyeicosatrienoic acids (EETs) are important modulators of endothelial cell homeostasis. We investigated the signaling pathway linking the activation of CYP 2C9 to enhanced endothelial cell proliferation. Overexpression of CYP 2C9 in cultured human endothelial cells markedly increased proliferation. This effect was paralleled by an up-regulation of the G(1) phase regulatory protein, cyclin D1. The specific CYP 2C9 inhibitor, sulfaphenazole, prevented both the enhanced cell proliferation and up-regulation of cyclin D1. CYP 2C9 overexpression also decreased the activity of the c-Jun N-terminal kinase (JNK). Coexpression of wild type JNK with CYP 2C9 attenuated the CYP 2C9-induced increase in cyclin D1 expression and abolished the CYP 2C9-induced proliferation response. In contrast, cotransfecting dominant negative JNK with CYP 2C9 restored the CYP 2C9-mediated up-regulation of cyclin D1 and proliferation. The inactivation of JNK is linked to its dephosphorylation by dual specificity mitogen-activated protein (MAP) kinase phosphatases (MKPs). Overexpression of CYP 2C9 significantly increased the expression of MKP-1, as did incubation with 11,12-EET. These data demonstrate that the mitogenic effect of CYP 2C9 is due to the generation of EETs, which promote the MKP-1-mediated dephosphorylation and inactivation of JNK, effects ultimately culminating in the expression of cyclin D1 and endothelial cell proliferation.
Potente
Michael
M
Institut für Kardiovaskuläre Physiologie, Klinikum der Johann Wolfgang Goethe-Universität, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany.
Michaelis
U Ruth
UR
Fisslthaler
Beate
B
Busse
Rudi
R
Fleming
Ingrid
I
D015126:8,11,14-Eicosatrienoic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D001189:Aryl Hydrocarbon Hydroxylases; D018797:Cell Cycle Proteins; D002455:Cell Division / Q000502:physiology*; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free; D019938:Cyclin D1 / Q000235:genetics*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D054638:Dual Specificity Phosphatase 1; D004730:Endothelium, Vascular / Q000166:cytology* / Q000201:enzymology; D004790:Enzyme Induction; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D017874:Immediate-Early Proteins / Q000235:genetics*; D048031:JNK Mitogen-Activated Protein Kinases; D007700:Kinetics; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*; D039181:Steroid 16-alpha-Hydroxylase; D013250:Steroid Hydroxylases / Q000378:metabolism*; D013426:Sulfaphenazole / Q000494:pharmacology; D013997:Time Factors; D014162:Transfection; D014471:Umbilical Veins; D048051:p38 Mitogen-Activated Protein Kinases
D018797:Cell Cycle Proteins; D016895:Culture Media, Serum-Free; D017874:Immediate-Early Proteins; D013426:Sulfaphenazole; D019938:Cyclin D1; C046783:11,12-epoxy-5,8,14-eicosatrienoic acid; D003577:Cytochrome P-450 Enzyme System; D006861:Hydrogen Peroxide; D013250:Steroid Hydroxylases; D001189:Aryl Hydrocarbon Hydroxylases; D039181:Steroid 16-alpha-Hydroxylase; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; C517019:DUSP1 protein, human; D054638:Dual Specificity Phosphatase 1; D017027:Protein Tyrosine Phosphatases; D015126:8,11,14-Eicosatrienoic Acid