Anti-inflammatory effects of luteolin and luteoloside from Taraxacum coreanum in RAW264.7 macrophage cells

The effects of luteolin (LT) and luteoloside (LS) from Taraxacum coreanum, using lipopolysaccharide (LPS)/interferon-gamma (IFN-γ)-induced RAW264.7 macrophage cells, on anti-inflammation were investigated. Our study was focused on the ethyl acetate fraction from T. coreanum (ETC) and its active compounds and their protective role against inflammation. The ETC and its active compounds, LT and LS, showed dose-dependent inhibitory activity against the production of nitric oxide (NO) and reactive oxygen species (ROS) in LPS/IFN-γ-stimulated RAW264.7 cells. In addition, ETC and its active compounds inactivated nuclear factor-kappa B and down-regulated inflammatory mediators. The results also showed that treatment with ETC, LT, and LS decrease pro-inflammatory cytokines, tumor necrosis factor-alpha, and interleukin-6. In conclusion, our studies indicated that ETC has anti-inflammatory activity owing to inhibition of NO/ROS generation and down-regulation of inflammatory mediators and cytokines. Moreover, LT and LS are bioactive compounds of ETC with protective effects against inflammation.