The p38 MAPK inhibitor JLU1124 inhibits the inflammatory response induced by lipopolysaccharide through the MAPK-NF-κB pathway in RAW264.7 macrophages

Int Immunopharmacol. 2013 Nov;17(3):785-92. doi: 10.1016/j.intimp.2013.09.001. Epub 2013 Sep 23.

Abstract

Our previous results showed that JLU1124 is a potent p38 mitogen-activated protein kinase (MAPK) inhibitor. Compared to the classic p38 MAPK inhibitor SB203580, JLU1124 inhibits p38 phosphorylation at low concentrations without cytotoxicity on cells. p38 MAPK is a known target for inflammation treatment. Thus, we became interested in whether JLU1124 has anti-inflammatory effects. We used LPS stimulated RAW264.7 macrophages as a model of inflammation to evaluate the anti-inflammatory effects of JLU1124. Our results showed that p38 phosphorylation, the production of nitric oxide (NO), interleukin (IL)-6 and tumor necrosis factor (TNF)-α, the mRNA and protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were enhanced by lipopolysaccharide (LPS). At concentrations of less than 10 μmol/L, JLU1124 inhibits p38 phosphorylation in a dose-dependent manner and significantly suppresses LPS-induced production of NO, IL-6 and TNF-α, and decreases the expressions of iNOS and COX-2 in RAW264.7 macrophages which indicate that JLU1124 has anti-inflammatory effects. However, JLU1124 has no significant effect on the phosphorylation of extracellular signal-regulated kinase1/2 and c-Jun NH2-terminal kinase which was involved in inflammation. Furthermore, our results showed that JLU1124 inhibits NF-κB inhibitor (IκB)α phosphorylation, nuclear translocation and transcriptional activity of NF-κB induced by LPS which may be through suppression of Akt phosphorylation. In conclusion, our study indicates that JLU1124 efficiently inhibits p38 phosphorylation and has anti-inflammatory effects in LPS-treated RAW264.7 macrophages. The anti-inflammatory mechanism of JLU1124 is mainly through decreasing Akt phosphorylation and inhibiting IκBα phosphorylation, thus suppressing NF-κB activation and nuclear translocation.

Keywords: Anti-inflammatory; JLU1124; Lipopolysaccharide; NF-κB; p38 MAPK.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Line
  • Cyclooxygenase 2 / genetics
  • Cyclooxygenase 2 / metabolism
  • Imidazoles / pharmacology
  • Inflammation / metabolism*
  • Interleukin-6 / metabolism
  • Lipopolysaccharides
  • Macrophages / drug effects*
  • Macrophages / metabolism
  • Mice
  • Mitogen-Activated Protein Kinases / antagonists & inhibitors*
  • Mitogen-Activated Protein Kinases / metabolism
  • NF-kappa B / metabolism
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase Type II / genetics
  • Nitric Oxide Synthase Type II / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Pyridines / pharmacology
  • Signal Transduction
  • Sulfones / pharmacology*
  • Thiazepines / pharmacology*
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Anti-Inflammatory Agents
  • Imidazoles
  • Interleukin-6
  • JLU1124
  • Lipopolysaccharides
  • NF-kappa B
  • Pyridines
  • Sulfones
  • Thiazepines
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide
  • Nitric Oxide Synthase Type II
  • Nos2 protein, mouse
  • Ptgs2 protein, mouse
  • Cyclooxygenase 2
  • Proto-Oncogene Proteins c-akt
  • Mitogen-Activated Protein Kinases
  • SB 203580