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

Abstract EN

Rhus verniciflua is widely known for its antioxidant, antibacterial, anticancer, and antiaging efficacy and α-glucosidase inhibition.

This study was designed whether Rhus verniciflua extracts inhibit the IgE-antigen-mediated allergic reaction in RBL-2H3 mast cells, and it further investigated the FcεRI- and arachidonate-signaling by which Rhus verniciflua extracts exert its antiallergic effects.

IgE-antigen-sensitized RBL-2H3 mast cells were investigated for the cytotoxicity of Rhus verniciflua extracts and β-hexosaminidase release, and inflammatory mediators (e.g., TNF-α, IL-4, IL-6, histamine, and PGD2) were then assessed.

Additionally, we examined expressions of genes involved in arachidonate- and FcεRI-signaling pathway in RBL-2H3.

Rhus verniciflua extracts inhibited β-hexosaminidase release and production of the inflammatory mediators in RBL-2H3.

Rhus verniciflua extracts reduced amounts of histamine and expressions of FcεRI signaling-related genes such as Lyn and Syk and phosphorylation of extracellular signal-regulated kinase in mast cells.

Finally, in late allergic responses, Rhus verniciflua extracts reduced PGD2 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 Rhus verniciflua extracts in FcɛRI-mediated allergic reaction.