Effusanin C inhibits inflammatory responses via blocking NF-κB and MAPK signaling in monocytes

Effusanin C, a constituent of Isodon japonicus, has been used in oriental countries as a traditional folk medicine to treat inflammatory diseases, but its mechanism of action remains unknown. Here, we investigate the inhibitory activity of effusanin C in inflammatory monocytes. Effusanin C markedly inhibited the production of inflammatory mediators including nitric oxide, IL-1β, and TNF-α in macrophages and dendritic cells. Furthermore, molecular studies showed that effusanin C inhibited phosphorylation of p38, JNK, and ERK, degradation of IκBβ, and nuclear translocation of NF-κB p50/p65 in these cells. Taken together, these data show that effusanin C inhibits inflammatory responses by blocking NF-κB and MAPK signalings in monocytes.