Eupatilin inhibits lipopolysaccharide-induced expression of inflammatory mediators in macrophages

Eupatilin (5,7-dihydroxy-3,4,6-trimethoxyflavone) is a pharmacologically active ingredients in Stillen TM, a drug for the gastric mucosal ulcers. Eupatilin has been known to possess anti-peptic, anti-cancer, and anti-allergy activity. In this report, we defined the effect of eupatilin on the endotoxin-induced inflammation in lipopolysaccharide (LPS)-stimulated macrophages. Mouse J774A.1 cell line and mouse peritoneal macrophages were used. Gene expression and production of inflammatory mediators were determined by real-time PCR and Western blot. Eupatilin dose-dependently suppressed LPS-induced expression of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO). Eupatilin decreased LPS-induced expression of inflammatory mediators and pro-inflammatory cytokines such as cyclooxygenase-2, monocyte chemoattractant protein-1, tumor necrosis factor-α, interleukin (IL)-1β and IL-6. In addition, this suppression of inflammatory mediators was nuclear factor (NF)-κB dependent. Our findings imply that eupatilin suppresses inflammatory responses by the inhibition of NF-κB signaling pathway, and downstream inflammatory mediators in endotoxin-stimulated macrophages.