Tartary buckwheat on nitric oxide-induced inflammation in RAW264.7 macrophage cells.

We investigated the effects of tartary buckwheat (TB, Fagopyrum tataricum) on the production of pro-inflammatory mediators in lipopolysaccharide (LPS)- and interferon (IFN)-γ-stimulated RAW264.7 cells. We evaluated the anti-inflammatory effects of TB against the LPS- and IFN-γ-stimulated inflammatory response in RAW264.7 macrophage cells. We fractionated TB to obtain 4 fractions including the n-hexane, methylene chloride, ethyl acetate (EtOAc), and n-butanol fractions. In addition, rutin was isolated and identified from the EtOAc fraction. The 4 fractions and rutin effectively inhibited the production of reactive oxygen species, nitric oxide (NO), and interleukin-6. In addition, the mRNA expression levels of pro-inflammatory factors including nuclear factor kappa B, cyclooxygenase-2, and inducible NO synthase were down-regulated in LPS- and IFN-γ-stimulated RAW264.7 cells following treatment with the 4 fractions and rutin. The present study suggests that TB could induce anti-inflammation by regulating the expression of inflammatory mediators.