Effect of Extract on IgE-Antigen-Mediated Allergic Reaction in Rat Basophilic Leukemic RBL-2H3 Mast Cells and Passive Cutaneous Anaphylaxis in Mice.

is widely known for its antioxidant, antibacterial, anticancer, and antiaging efficacy and -glucosidase inhibition. This study was designed whether extracts inhibit the IgE-antigen-mediated allergic reaction in RBL-2H3 mast cells, and it further investigated the FcRI- and arachidonate-signaling by which extracts exert its antiallergic effects. IgE-antigen-sensitized RBL-2H3 mast cells were investigated for the cytotoxicity of extracts and -hexosaminidase release, and inflammatory mediators (e.g., TNF-, IL-4, IL-6, histamine, and PGD) were then assessed. Additionally, we examined expressions of genes involved in arachidonate- and FcRI-signaling pathway in RBL-2H3. extracts inhibited -hexosaminidase release and production of the inflammatory mediators in RBL-2H3. extracts reduced amounts of histamine and expressions of FcRI signaling-related genes such as Lyn and Syk and phosphorylation of extracellular signal-regulated kinase in mast cells. Finally, in late allergic responses, extracts reduced PGD release and COX-2 and cPLA2 phosphorylation expressions from IgE-antigen-mediated mast cells. Lastly, 250-500 mg/kg RVE significantly attenuated the Ag/IgE-induced passive cutaneous anaphylaxis (PCA) reaction in mice. These findings provide novel information on the molecular mechanisms underlying the antiallergy properties of extracts in FcRI-mediated allergic reaction.