Echinacea purpurea extract inhibits LPS-induced inflammatory response by interfering with TLR4-mediated NF-κB and MAPKs signaling pathways

Abstract

Echinacea purpurea (Asteraceae family) is widely used in the European countries and the United States due to its proven immune enhancement and anti-inflammatory effects. Echinacea purpurea has been reported prevent and treat upper respiratory tract infections and common cold, but the underlying molecular mechanisms are not well understood. In the present study, we examined the anti-inflammatory effects and molecular mechanisms of Echinacea purpurea (EP) extract using lipopolysaccharide (LPS)-stimulated signal pathways in RAW264.7 cells. Our results suggest that EP extract exerts anti-inflammatory effects by down-regulating the expression of LPS-induced toll-like receptor 4 (TLR4), subsequently inhibiting the activation of nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling pathways and suppression of the release of pro-inflammatory cytokines. These results suggest that EP extract is a potential therapeutic agent for inflammatory diseases.