Quercus mongolica (QM), which belongs to fagaceae, is one of the oak native to Korea. We evaluated the antiinflammatory effect of branches extracted with 70% ethanol of QM (QM-B) and elucidated the potential signaling pathway in LPS-induced RAW264.7 cells. The QM-B showed anti-inflammatory activity through inhibition of NO production. The QM-B dose-dependently suppressed NO production by inhibiting iNOS, COX-2 and IL-6 expression in LPS-induced RAW264.7 cells. The QM-B inhibited the degradation and phosphorylation of IκB-α and NF-κB activation. The QM-B suppressed the phosphorylation of p38 and ERK1/2. Also, the QM-B increased HO-1 expression. These results suggested that QM-B may utilize anti-inflammatory activity by suppressing NF-κB and MAPK signaling pathway and inducing HO-1 expression indicated that the QM-B can be used as a natural anti-inflammatory drugs.

Abstract
Introduction
Materials and methods
    Materials
    Sample preparation
    Cell culture and treatment
    Cell viability assay
    Measurement of NO production
    Western blot analysis
    Reverse transcriptase-polymerase chain reaction (RT-PCR)
    Statistical analysis
Results and Discussion
    The effect of QM-B on NO production and iNOS, COX-2 and IL-6 expression in LPS-induced RAW264.7 cells
    The effect of QM-B on NF-κB signaling activation in LPS-induced RAW264.7 cells
    The effect of QM-B on MAPK signaling activation in LPS-induced RAW264.7 cells
    The effect of QM-B on HO-1 activation in RAW264.7 cells
References

• Hyun Ji Eo(Forest Medicinal Resources Research Center, National Institute of Forest Science)
• Youngki Park(Forest Medicinal Resources Research Center, National Institute of Forest Science)
• Jin Taek Kang(Division of Forest Industry Research, National Institute of Forest Science)
• Gwang Hun Park(Forest Medicinal Resources Research Center, National Institute of Forest Science) Corresponding author