Anti‐inflammatory activities of Lessertia frutescens (Sutherlandia) extract in murine macrophages

Abstract

IntroductionLessertia frutescens (Sutherlandia) is a medicinal plant native to southern Africa and is traditionally used in various inflammatory situations. We sought to characterize the bioactivity of an ethanolic extract from Sutherlandia (SE) using a murine macrophage cell line (RAW 264.7) and primary murine macrophages.Experimental DesignCells were exposed to various concentrations of SE for 30 min, then stimulated with IFNγ along with various toll‐like receptor (TLR) ligands for 20 hours. The production of nitric oxide (NO), several pro‐inflammatory cytokines/chemokines, as well as the expression of iNOS protein was evaluated 20 hr later.ResultsSE treatment significantly and dose‐dependently reduced NO production induced by the TLR5 ligand, flagellin, TLR4 ligand, LPS, and TLR2/6 ligand, Pam2CSK. Similar effects were observed for RAW 264.7 cells and primary murine macrophages. The impact of SE on iNOS protein expression was consistent with the observed reductions in NO production. SE treatment also diminished the production of various pro‐inflammatory cytokines and chemokines upon stimulation of macrophages with IFN‐γ and TLR ligands.ConclusionsSutherlandia ethanolic extract has potent anti‐inflammatory activities in murine macrophages. Funding from the Office of Dietary Supplement, NIH: P50 AT006273‐01.Grant Funding Source: ODS, NIH