Involvement of p38 MAPK and ATF-2 signaling pathway in anti-inflammatory effect of a novel compound bis[(5-methyl)2-furyl](4-nitrophenyl)methane on lipopolysaccharide-stimulated macrophages

Abstract

Activated macrophages produce various pro-inflammatory mediators such as inducible nitric oxide synthase (iNOS)-derived nitric oxide (NO) and cyclooxygenase (COX)-2-derived prostaglandin E₂ (PGE₂) during inflammatory response. However, overproduction of NO and PGE₂ appears to be involved in pathogenesis of various inflammatory diseases. Therefore, inhibition of NO and PGE₂ production might be useful for the treatment of inflammatory-related diseases. In this study, the bis[(5-methyl)2-furyl](4-nitrophenyl)methane or BFNM was evaluated for the anti-inflammatory activity and mechanism of action in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage. BFNM inhibited NO and PGE₂ production in a concentration-dependent manner and down-regulated the expression of iNOS and COX-2 at mRNA and protein levels. BFNM suppressed nuclear translocation of NF-κB p65 subunit only very slightly, and failed to decrease NF-κB DNA binding activity. In contrast, the compound significantly reduced phosphorylation of p38 MAPK and ATF-2, a component of AP-1 known to be involved in the transcriptional regulation of iNOS and COX-2, in a dose-dependent manner in LPS-induced cells. Collectively, these results suggest that BFNM has an anti-inflammatory effect in RAW 264.7 macrophages, at least in part, by suppression of NO and PGE₂ production. The inhibitory effect of BFNM is mediated mainly via the p38 MAPK/ATF-2 signaling pathway. Thus, BFNM would be a lead compound for the development of novel anti-inflammatory agents.

Keywords: Anti-inflammatory; Bis[(5-methyl)2-furyl](4-nitrophenyl)methane; Macrophage; Nitric oxide; Prostaglandin E(2).