Protective Effects of Acorn (Quercus acutissima CARR.) against IgE-mediated Allergic and Ovalbumin (OVA)-Induced Asthmatic Responses via Inhibition of Oxidative Stress

ABSTRACT − This work was performed to investigate the protective effect of ethanol extract (AEx) from acorn (Quercusacutissima CARR.) against allergic mediated responses in asthma model cells and mice. The AEx inhibited antigen-stim-ulated cytokine production such as interleukin (IL)-4, IL-13 and tumor necrosis factor-α (TNF-α) and AEx also inhibitedintracellular reactive oxygen species (ROS) generation against IgE-mediated allergic response in rat basophilic leukaemiaRBL-2H3 cells. The ovalbumin (OVA)-sensitized mice were orally administered with AEx (100 or 300 mg/kg) and authentictannic acid (75 mg/kg) every day for 15 days. Increased TNF-α production by OVA-sensitization/challenge was significantlyreduced by administration of AEx. The serum triglyceride levels of asthma mice were significantly reduced after feedingfor 15 days with tannic acid or AEx. The mice fed with tannic acid or AEx also exhibited a significant reduction in bodyweights compared to those of asthma control group. The AEx increased the heme oxygenase (HO)-1 mRNA expression inthe asthma model mice and showed DPPH radical scavenging activity. These results indicate that AEx protects against IgE-mediated allergic and OVA-induced asthmatic responses via direct and indirect antioxidant activities. Reduced triglycerideand body weights may provide additional protective benefits of AEx on allergic asthma.Key words