Anti-allergic property of 4,8-sphingadienine stereoisomers in vivo and in vitro model.

4,8-Sphingadienines (SD), metabolites of glucosylceramides (GlcCer), are sometimes determined as key mediators of the biological activity of dietary GlcCer, and cis / trans geometries of 4,8-SD have been reported to affect its activity. Since regulating excessive activation of mast cells seems an important way to ameliorate allergic diseases, this study was focused on cis/trans stereoisomeric-dependent inhibitory effects of 4,8-SD on mast cell activation. Degranulation of RBL-2H3 was inhibited by treatment of 4- cis -8- trans - and 4- cis -8- cis -SD, and their intradermal administrations ameliorated ear edema in passive cutaneous anaphylaxis reaction, but 4- trans -8- trans - and 4- trans -8- cis -SD did not. Although the activation of mast cells depends on the bound IgE contents, those stereoisomers did not affect IgE contents on RBL-2H3 cells after the sensitization of anti-TNP IgE. These results indicated that 4- cis -8- trans - and 4- cis -8- cis -SD directly inhibit the activation of mast cells. In conclusion, it was assumed that 4,8-SD stereoisomers with cis double bond at C4-position shows anti-allergic activity by inhibiting downstream pathway after activation by the binding of IgE to mast cells. [Display omitted] • This study was focused on cis/trans stereoisomeric-dependent inhibitory effects of 4,8-sphingadiene, a component of glucosylceramide, on mast cell activation. • Degranulation of RBL-2H3 and passive cutaneous anaphylaxis reaction were inhibited by treatment of 4- cis -8- trans - and 4- cis -8- cis -sphingadiene. • 4,8-sphingadiene stereoisomers with trans double bond at C4-position did show no activities in both assays. • 4- cis -8- trans - and 4- cis -8- cis -sphingadiene did not affect IgE contents on RBL-2H3 cells after the sensitization of anti-TNP IgE. • It was assumed that 4,8-SD stereoisomers with cis double bond at C4-position are important to show anti-allergic activity. [ABSTRACT FROM AUTHOR]