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 E (2) (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 (IC (50): 0.175 microM) and PGE (2) (IC (50): 0.0195 microM) 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 kappaBalpha (IkappaBalpha) and degradation of IkappaBalpha associated with nuclear factor kappaB (NF-kappaB) activation. Furthermore, panduratin A inhibited LPS-induced NF-kappaB transcriptional activity in a dose-dependent manner. These results suggest that panduratin A could exert its inhibitory effects on the production of NO and PGE (2) through the suppression of NF-kappaB activation, indicating its potential for use as an anti-inflammatory agent.