In-vitro and in-vivo anti-allergic actions of Arecae semen.

The effects of various extracts from oriental medicinal herbs on mast cell-mediated allergic reactions have been investigated. Among the extracts, Arecae semen was the most potent inhibitor of antigen-induced degranulation in RBL-2H3 mast cells. A. semen inhibited DNP-BSA- and compound 48/80-induced degranulation in RBL-2H3 mast cells with IC(50) values of approximately 53 and 52 microg mL(-1), respectively, and inhibited compound 48/80-induced systemic anaphylaxis by 46% at 300 mg kg(-1) in mice. A. semen also inhibited the expression of TNF-alpha and the activation of mitogen activated protein kinase, ERK1/2, which is critical for the production of inflammatory cytokines in mast cells, as indicated by the suppression of the activating phosphorylation of ERK1/2. These results suggest that A. semen may be useful for the treatment of various immediate and delayed allergic diseases.