Inhibition of inducible nitric oxide production by Caryota urens and its active constituents umbelliferone and rutin.

Inducible Nitric Oxide Synthase (iNOS) is a key mediator in a variety of diseases, and thus it is interesting to discover new iNOS inhibitors. This study aimed to evaluate if the hydroalcoholic leaf extract of Caryota urens (CULHA) consisting of rutin and umbelliferone prevents inflammation in response to external stimuli. To demonstrate the therapeutic potential of CULHA against inflammatory diseases, nitric oxide production (NO) mediated by iNOS was evaluated. In lipopolysaccharide induced RAW 264.7 cells, CULHA, rutin and umbelliferone exhibited remarkable inhibition of NO at 61%, 30% and 41% respectively without affecting the cell viability at the highest concentration tested. In conclusion, results obtained in this work substantiate the traditional uses of this plant and brings a brief understanding of their anti inflammatory potential.