Extracts with anti-inflammatory activities from Acanthopanax trifoliatus (L.) Merr. by inhibiting LPS-induced expression of iNOS and COX-2

Abstract

Acanthopanax trifoliatus (L.) Merr. have been used as folk medicine to treat various diseases traditionally and the young leaves and shoots of A. trifoliatus are popularly consumed as vegetables and herbal tea in southern China. In the study, we firstly tested the cytotoxicity and NO production of 18 fractions that extracted from the leaves, stems and roots of A. trifoliatus to select the bioactive fraction. The increasing evidence suggested that the dichloromethane extract prepared from stems of A. trifoliatus (ATSDC) have anti-inflammatory activity. Therefore, the study followed to investigate the effects of ATSDC on the inflammatory response and the molecular mechanisms underpinning this effect in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The manuscript showed that ATSDC effectively inhibited NO production in LPS-stimulated cells and significantly reduced the production of pro-inflammatory cytokines IL-6, at a dose of 40 µg/mL, whereas TNF-α production tended to decrease under ATSDC treatment. We also confirmed a dose-dependent and significant inhibition of iNOS and COX-2 protein expression. In conclusion, ATSDC exerted strong inhibitory effect on the expression of iNOS and COX-2 protein in LPS-induced RAW 264.7 macrophages and could be potentially used in treatment of inflammatory-related diseases in the future.

Keywords:
Acanthopanax trifoliatus (L.) Merr.; dichloromethane extract; anti-inflammatory activities; iNOS and COX-2; RAW 264.7 macrophages