Specific inhibitors of p38 and extracellular signal-regulated kinase mitogen-activated protein kinase pathways block inducible nitric oxide synthase and tumor necrosis factor accumulation in murine macrophages stimulated with lipopolysaccharide and interferon-gamma

J Infect Dis. 1999 Apr;179(4):939-44. doi: 10.1086/314659.

Abstract

Whether p38 and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase cascades are required for inducible nitric oxide synthase (iNOS) and tumor necrosis factor (TNF) accumulation in RAW 264.7 murine macrophages exposed to lipopolysaccharide (LPS) plus recombinant interferon-gamma (rIFN-gamma) was investigated. By use of Western blotting for iNOS detection and ELISA for quantitation of TNF secretion, three selective inhibitors of these pathways were tested (the p38 inhibitors SB202190 and SB203580 and the MEK 1,2/ERK inhibitor PD98059). Dose-related inhibition of iNOS production was demonstrated when inhibitors were added 1 h before, simultaneously with, or 1 h after LPS plus rIFN-gamma stimulation. In contrast, inhibition of TNF secretion was observed only when cells were preincubated with these agents. Thus, both the p38 and ERK pathways are involved in the up-regulation of iNOS and TNF production by murine macrophages, and specific inhibitors of these pathways block macrophage iNOS production even when added 1 h after activation of these cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium-Calmodulin-Dependent Protein Kinases / antagonists & inhibitors
  • Calcium-Calmodulin-Dependent Protein Kinases / physiology*
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Flavonoids / pharmacology
  • Humans
  • Imidazoles / pharmacology
  • Interferon-gamma / pharmacology*
  • Lipopolysaccharides / pharmacology*
  • Macrophages
  • Mitogen-Activated Protein Kinases*
  • Nitric Oxide / biosynthesis
  • Nitric Oxide Synthase / antagonists & inhibitors
  • Nitric Oxide Synthase / biosynthesis*
  • Nitric Oxide Synthase Type II
  • Pyridines / pharmacology
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors
  • Tumor Necrosis Factor-alpha / biosynthesis*
  • p38 Mitogen-Activated Protein Kinases

Substances

  • Flavonoids
  • Imidazoles
  • Lipopolysaccharides
  • Pyridines
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide
  • Interferon-gamma
  • NOS2 protein, human
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type II
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Mitogen-Activated Protein Kinases
  • p38 Mitogen-Activated Protein Kinases
  • SB 203580
  • 4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole
  • 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one