Inhibition of Nitric Oxide Production in LPS-Stimulated Raw 264.7 Cells by Dolichandrone Atrovirens Bark

Abstract

In traditional systems of medicine, the bark of Dolichandroneatrovirens has been used to treat various disorders. The main aim of this study was to determine the anti-inflammatory effect of D. atrovirens bark through the inhibition of nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 cells.For this purpose, preliminary phytochemical composition and in vitro antioxidant activities of various solvent extracts of D. atrovirens bark were evaluated to select the most effective extract.The methanol extract of D.atrovirens registered the highest amount of total phenolics (476.2 mg GAE/g) and flavonoid (129.0 mg RE/g)contents witha strong antioxidant activity as measured in DPPH (IC50 of 19.52 μg/mL) and ABTS (IC50of 10.82 μg/mL) scavenging activities.Hence, the methanol extract was selected for cell line study. Further, the methanol extract of D. atrovirens effectively inhibited the production of NO in RAW 264.7 cells induced by LPS (13.1 μM at the concentration of 80 μg/mL). It could be concluded that the presence of higher level of total phenolic components in the methanol extract of D. atrovirens bark might be responsible for reducing the NO level in cells.