Young Yum pill inhibits inflammatory mediators and nuclear factor-kappa B signaling in lipopolysaccharide-stimulated RAW 264.7 macrophages

OBJECTIVE: To investigate the effect of Young Yum pill (YYP) on inflammatory mediators in cultured RAW 264.7 cells and elucidate the nuclear factor- kappa 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 LPS-induced 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 LPS-stimulated RAW 264.7 macrophages, providing a pharmacological basis for the use of YYP in treating inflammatory disorders.