Inhibitory effect of mast cell-mediated immediate-type allergic reactions in rats by Spirulina

We investigated the effect of spirulina on mast cell-mediated immediate-type allergic reactions. Spirulina dose-dependently inhibited the systemic allergic reaction induced by compound 48/80 in rats. Spirulina inhibited compound 48/80-induced allergic reaction 100% with doses of 100-1000 mu g/g body weight, i.p. Spirulina (10-1000 mu g/g body weight,i.p.) also significantly inhibited local allergic reaction activated by anti-dinitrophenyl (DNP) IgE. When rats were pretreated with spirulina at a concentration ranging from 0.01 to 1000 mu g/g body weight, i.p., the serum histamine levels were reduced in a dose-dependent manner. Spirulina (0.001 to 10 mu g/mL) dose dependently inhibited histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP in RPMC, when spirulina (10 mu g/mL) was added, transiently and significantly increased about 70-fold at 10 sec compared with that of control cells. Moreover, spirulina (10 mu g/mL) had a significant inhibitory effect on anti-DNP IgE induced tumor necrosis factor-alpha production. These results indicate that spirulina inhibits mast cell-mediated immediate-type allergic reactions in vivo and in vitro. (C) 1998 Elsevier Science Inc.