In the previous study, the mixture of the rhizome of Anemarrhena asphodeloides (AA, family Liliaceae) and the rhizome of Coptidis chinensis (CC, family Ranunculaceae) (AC-mix) improved TNBS- or
oxazolone-induced
colitis in mice. Therefore, to investigate its anticolitic mechanism, we measured its effect in acute and chronic DSS-induced colitic mice and investigated its anti-inflammatory mechanism in peritoneal macrophages. AC-mix potently suppressed DSS-induced
body weight loss, colon shortening,
myeloperoxidase activity, and TNF-α, IL-1β, and
IL-6 expressions in acute or chronic DSS-stimulated colitic mice. Among AC-mix ingredients, AA, CC, and their main constituents
mangiferin and
berberine potently inhibited the expression of proinflammatory
cytokines TNF-α and IL-1β, as well as the activation of NF-κB in LPS-stimulated peritoneal macrophages. AA and
mangiferin potently inhibited IRAK phosphorylation, but CC and
berberine potently inhibited the binding of LPS to TLR4 on macrophages, as well as the phosphorylation of IRAK1. AC-mix potently inhibited IRAK phosphorylation and LPS binding to TLR4 on macrophages. Based on these findings, AC-mix may ameliorate
colitis by the synergistic inhibition of IRAK phosphorylation and LPS binding to TLR4 on macrophages.