Contribution of covalent protein modification to the antiinflammatory effects of cyclopentenone prostaglandins.
Cyclopentenone prostaglandins, which are produced during inflammatory processes, may exert a negative feedback on inflammation. These reactive compounds may form covalent adducts with thiol groups in glutathione or in proteins. The transcription factor NF-kappaB is key for the expression of numerous proinflammatory genes. We have observed that treatment of mesangial cells with 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)) inhibits the cytokine-elicited DNA binding activity of NF-kappaB, both in intact cells and in isolated nuclear extracts, thus suggesting a direct effect on DNA binding. By using a biotinylated 15d-PGJ(2) derivative, we have observed that 15d-PGJ(2) forms an adduct with the p50 subunit of NF-kappaB, as shown by Western blot and detection with horseradish peroxidase-conjugated streptavidin. In contrast, a p50 construct that bears a mutation in the cysteine residue involved in DNA binding (Cys62Ser) and is not susceptible to inhibition by 15d-PGJ(2) does not incorporate biotinylated 15d-PGJ(2). The labeling of several polypeptides after incubation of cells with biotinylated 15d-PGJ(2) suggests that there may be multiple targets for modification by 15d-PGJ(2). We propose that the covalent modification of NF-kappaB (and potentially other proteins) by 15d-PGJ(2) may contribute to the antiinflammatory effects of this prostaglandin.
Pérez-Sala
Dolores
D
Departamento de Estructura y Función de Proteínas e Instituto Reina Sofía de Investigaciones Nefrológicas, Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Velázquez, 144, 28006 Madrid, Spain.
Cernuda-Morollón
Eva
E
Pineda-Molina
Estela
E
Cañada
F Javier
FJ
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D019921:Biotinylation; D002478:Cells, Cultured; D003517:Cyclopentanes / Q000494:pharmacology*; D011464:Epoprostenol / Q000494:pharmacology; D005920:Glomerular Mesangium / Q000187:drug effects / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism; D011453:Prostaglandins / Q000494:pharmacology*; D011506:Proteins / Q000378:metabolism*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D003517:Cyclopentanes; D016328:NF-kappa B; D011453:Prostaglandins; D011506:Proteins; D011464:Epoprostenol; C013905:cyclopentenone