Anti-inflammatory effect of Opuntia robusta extract against LPS-stimulated RAW 264.7 macrophage cells

Opuntia robusta is known to have beneficial effects on human health, such as antioxidant, anti-diabetic effect, and improvement of constipation, etc.This study investigated the antiinflammatory activity of O. robusta stem extract (ORE) and its active component, 3-O-methylquercetin (3-MeQ), in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages.It was confirmed that ORE inhibited nitric oxide (NO) production and pro-inflammatory cytokine release (IL-1β) induced by LPS.According to the results of the Western blotting analysis, the protein expression levels of inflammatory mediators and cytokines (p-NF-κB, iNOS, COX-2, IL-6, IL-1β, and TNF-α) were decreased by treatment with ORE.The 3-MeQ also suppressed the LPS-stimulated pro-inflammatory mediators and cytokines production (IL-1β and IL-6), but did not alter NO production and iNOS protein expression.From these results, ORE and its active compound, 3-MeQ, have anti-inflammatory activity against LPS, suggesting the possibility of being a functional food ingredient.