Role of interferon regulatory factor-1 and mitogen-activated protein kinase pathways in the induction of nitric oxide synthase-2 in retinal pigmented epithelial cells.
J Biol Chem
; 274(8): 4794-800, 1999 Feb 19.
Article
em En
| MEDLINE
| ID: mdl-9988718
ABSTRACT
Bovine retinal pigmented epithelial cells express an inducible nitric oxide synthase (NOS-2) after activation with interferon-gamma (IFN-gamma) and lipopolysaccharide (LPS). Experiments were performed to investigate the involvement of interferon regulatory factor-1 (IRF-1) on NOS-2 induction and its regulation by NOS-2 inhibitors such as pyrrolidine dithiocarbamate (PDTC), an antioxidant, or protein kinase inhibitors. Analysis by transitory transfections showed that LPS, alone or with IFN-gamma, stimulated activity of the murine NOS-2 promoter fragment linked upstream of luciferase and its suppression by PDTC and by the different protein kinase inhibitors, genistein (tyrosine kinase inhibitor), PD98059 (mitogen-actived protein (MAP) kinase kinase inhibitor), and SB 203580 (p38 MAP inhibitor). Using specific antibodies, we have confirmed that extracellular signal-regulated kinases and p38 MAP kinase were activated by LPS and IFN-gamma in retinal pigmented epithelial cells. Analysis by reverse transcriptase-polymerase chain reaction, Western blot, and electrophoretic mobility shift assay demonstrated that IFN-gamma alone or combined with LPS induced an accumulation of IRF-1 mRNA and protein and IRF-1 DNA binding. Transfections assays with the IRF-1 promoter showed an induction of this promoter with IFN-gamma, potentiated by LPS. The decrease of LPS/IFN-gamma-induced IRF-1 promoter activity, IRF-1 synthesis, and IRF-1 activation, by PDTC, genistein, PD98059, and SB 203580, could explained in part the inhibition of the NOS-2 induction by these compounds. Our results demonstrate that IRF-1 is necessary for NOS-2 induction by LPS and IFN-gamma and that its synthesis requires the involvement of a redox-sensitive step, the activation of tyrosine kinases, and extracellular signal-regulated kinases 1/2 and p38 MAP kinases.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosfoproteínas
/
Epitélio Pigmentado Ocular
/
Proteínas Quinases Dependentes de Cálcio-Calmodulina
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Óxido Nítrico Sintase
/
Proteínas de Ligação a DNA
Limite:
Animals
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
1999
Tipo de documento:
Article
País de afiliação:
França