In Vitro Anti-Inflammatory Activity of Panduratin A Isolated from Kaempferia pandurata in RAW264.7 Cells

An active compound identified as panduratin A was isolated from a methanol extract of Kaempferia pandurata (Zingiberaceae). We examined the effect of panduratin A on nitric oxide (NO) and prostaglandin E₂ (PGE ₂) production induced by lipopolysaccharide (LPS) in RAW264.7 cells. Modulations of iNOS and COX-2 enzyme expression were evaluated by Western blotting, Panduratin A strongly inhibited both NO (IC₅₀:0.175 μM) and PGE₂ (IC₅₀:0.0195 μM) production and suppressed both iNOS and COX-2 enzyme expression without any appreciable cytotoxic effect on RAW264.7 cells in a dose-dependent manner. Panduratin A also suppressed the phosphorylation of inhibitor κBa (IκBα) and degradation of IκBα associated with nuclear factor κB (NF-κB) activation. Furthermore, panduratin A inhibited LPS-induced NF-κB transcriptional activity in a dose-dependent manner. These results suggest that panduratin A could exert its inhibitory effects on the production of NO and PGE₂ through the suppression of NF-κB activation, indicating its potential for use as an anti-inflammatory agent.