CEP-11004, an inhibitor of the SAPK/JNK pathway, reduces TNF-α release from lipopolysaccharide-treated cells and mice

Abstract

CEP-11004, a mixed lineage kinase (MLK) inhibitor, was examined for its effects on tumor necrosis factor-alpha (TNF-α) production in human THP-1 monocytes, mouse BV-2 microglia, and C57Bl/6 mice. CEP-11004 inhibited TNF-α secretion up to 90% in THP-1 cells incubated with 3 μg/ml lipopolysaccharide, with an IC50 of 137±14 nM. CEP-11004 also inhibited TNF-α production in lipopolysaccharide-stimulated microglial cells, but did not inhibit the initial increase in TNF-α mRNA expression as measured by real-time polymerase chain reaction (PCR). The mitogen-activated protein kinases (MAPKs) phospho-c-jun N-terminal kinase (JNK), phospho-p38, and phospho-MAPK kinase 4 (MKK4) levels were increased in THP-1 cells following lipopolysaccharide treatment, and were reduced by CEP-11004 treatment. For in vivo studies, CEP-11004 was injected 2 h prior to lipopolysaccharide (20 mg/kg) administration. CEP-11004 significantly inhibited TNF-α production at doses of 1–10 mg/kg as measured by enzyme-linked immunosorbent assay (ELISA). These results suggest that MLK blockade may be useful in inhibiting pro-inflammatory cytokine production in a wide range of diseases.