Prostaglandins prevent inducible nitric oxide synthase protein expression by inhibiting nuclear factor-kappaB activation in J774 macrophages

FEBS Lett. 1998 Nov 27;440(1-2):76-80. doi: 10.1016/s0014-5793(98)01407-0.

Abstract

We investigated the effect of PGE2 and iloprost (a prostacyclin analogue) on inducible nitric oxide synthase (iNOS) protein expression and nuclear factor-kappaB (NF-kappaB) activation in lipopolysaccharide (LPS)-stimulated J774 macrophages. Incubation of J774 cells with LPS (10 microg/ml) caused an increase of iNOS protein expression which was prevented in a concentration-dependent fashion by PGE2 (0.1, 1, 10 microM) and iloprost (0.01, 0.1, 1 microM). Electrophoretic mobility shift assay indicated that both prostanoids blocked the activation of NF-kappaB, a transcription factor necessary for NO synthase induction. PGE2 and iloprost also blocked disappearance of I kappaB-alpha from cytosolic fraction and nuclear translocation of NF-kappaB subunits p50 and p65. These results show for the first time that PGE2 and iloprost down-regulate iNOS protein expression by inhibiting NF-kappaB activation and suggest a negative feed-back mechanism that may be important for limiting excessive or prolonged NO production in pathological events.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • Cell Line
  • Cell Nucleus / metabolism
  • Cytosol / metabolism
  • DNA Probes
  • DNA-Binding Proteins / metabolism
  • Dinoprostone / pharmacology*
  • Dose-Response Relationship, Drug
  • Gene Expression Regulation, Enzymologic
  • I-kappa B Proteins*
  • Iloprost / pharmacology*
  • Lipopolysaccharides / pharmacology
  • Macrophages / drug effects*
  • Macrophages / metabolism
  • Mice
  • NF-KappaB Inhibitor alpha
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / metabolism*
  • NF-kappa B p50 Subunit
  • Nitric Oxide Synthase / biosynthesis*
  • Nitric Oxide Synthase Type II
  • Nitrites / metabolism
  • Transcription Factor RelA

Substances

  • DNA Probes
  • DNA-Binding Proteins
  • I-kappa B Proteins
  • Lipopolysaccharides
  • NF-kappa B
  • NF-kappa B p50 Subunit
  • Nfkbia protein, mouse
  • Nitrites
  • Transcription Factor RelA
  • NF-KappaB Inhibitor alpha
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Iloprost
  • Dinoprostone