OBJECTIVE: To investigate the effect of Young Yum pill(YYP) on inflammatory mediators in cultured RAW 264.7 cells and elucidate the nuclear factorkappa B(NF-κB)-related mechanism behind the action.METHODS: YYP was extracted with 95% ethanol Lipopolysaccharide(LPS)-stimulated RAW 264.7 macrophages were used to evaluate the effect of YYP on inflammatory mediators.Production of nitric oxide(NO) and prostaglandin E2(PGE2) were measured by Griess test and enzyme-linked immunosorbent assay, respectively.The levels of genes and proteins involved in the generation of inflammatory mediators were examined using real-time polymerase chain reaction and Western blotting, respectively.RESULTS: YYP dose-dependently suppressed LPSinduced production of NO, PGE2 and tumor necrosis factor-α(TNF-α), and elevation of mRNA and protein levels of inducible NO synthase and cyclooxygenase-2 in RAW 264.7 macrophages.These observations were associated with decreased NF-κB p65 phosphorylation and nuclear localization, enhanced Akt(protein kinase B) phosphorylation, as well as reduced inhibitor of κB(IκB) α degradation and IκB kinase α/β phosphorylation.CONCLUSION: The present study demonstrated an inhibitory effect of YYP on the NF-κB-regulated inflammatory mediators NO, PGE2 and TNF-α in LPSstimulated RAW 264.7 macrophages, providing a pharmacological basis for the use of YYP in treating inflammatory disorders.