Constituents from Ageratina pichinchensis and Their Inhibitory Effect on Nitric Oxide Production

Abstract

In this study, we report on the isolation, purification, and anti-inflammatory evaluation of compounds from the plant species Ageratina pichinchensis. Using open-column chromatography, 11 known compounds were purified, which chemical structures were elucidated by nuclear magnetic resonance techniques (1D and 2D). All compounds were evaluated in an in vitro model of RAW 264.7 mouse macrophage cells, measuring the nitric oxide inhibition to determine the anti-inflammatory effect. The compound betuletol 3-O-β-glucoside (11) inhibited nitric oxide with a half-maximal inhibitory concentration (IC50) of 75.08 ± 3.07% at 75 µM; additionally, it inhibited the secretion of interleukin 6 (IL-6) and activation of the nuclear factor (NF-kβ). These results suggest that the anti-inflammatory effect attributed to A. pichinchensis species is promoted by compound 11, which could be considered a potential anti-inflammatory agent by suppressing the expression of NF-kβ target genes, such as those involved in the proinflammatory pathway and inducible nitric oxide synthase (iNOS).