c-Jun NH2-terminal kinase inhibitor anthra(1,9-cd)pyrazol-6(2H)-one reduces inducible nitric-oxide synthase expression by destabilizing mRNA in activated macrophages.
In this study, we investigated the role of c-Jun NH2-terminal kinase (JNK), a member of the mitogen-activated protein kinase (MAPK) family, in lipopolysaccharide (LPS)-stimulated inducible nitric-oxide synthase (iNOS) expression and nitric oxide (NO) production in J774 murine macrophages. Anthra(1,9-cd)pyrazol-6(2H)-one (SP600125), a pharmacological inhibitor of JNK, inhibited phosphorylation of c-Jun with an IC50 of 5 to 10 microM. At the same concentrations, SP600125 inhibited LPS-induced iNOS protein expression and NO production. SP600125 had no effect on the activation of nuclear factor kappaB, which is an important transcription factor for iNOS expression. SP600125 had no significant effect on iNOS mRNA levels if measured 4 h after LPS. In contrast, SP600125 reduced iNOS mRNA levels >90% when measured 8 h after LPS. These data suggest that SP600125 reduced iNOS mRNA stability, and this was confirmed in the mRNA degradation assay using actinomycin D, in which SP600125 reduced the iNOS mRNA half-life from 5 to 2 h. These results show that the JNK pathway is involved in the up-regulation of LPS-induced iNOS expression and NO production by a mechanism related to the stabilization of iNOS mRNA.
Lahti
Aleksi
A
The Immunopharmacological Research Group, University of Tampere Medical School, Tampere, Finland.
Jalonen
Ulla
U
Kankaanranta
Hannu
H
Moilanen
Eeva
E
D000818:Animals; D000873:Anthracenes / Q000494:pharmacology*; D000954:Antigens, Surface; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects*; D006207:Half-Life; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D / Q000096:biosynthesis; D048031:JNK Mitogen-Activated Protein Kinases; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000235:genetics / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II; D010766:Phosphorylation; D020871:RNA Stability; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000096:biosynthesis
D000873:Anthracenes; D000954:Antigens, Surface; D051959:ELAV Proteins; D000067780:ELAV-Like Protein 1; C098770:ELAVL1 protein, human; D004791:Enzyme Inhibitors; C000630986:HNRNPD protein, human; D000081035:Heterogeneous Nuclear Ribonucleoprotein D0; D034502:Heterogeneous-Nuclear Ribonucleoprotein D; C000630987:Hnrpd protein, mouse; D008070:Lipopolysaccharides; D016328:NF-kappa B; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; C432165:pyrazolanthrone; D009569:Nitric Oxide; D003513:Cycloheximide; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases