Inhibition of Mast Cell Degranulation by Phycoerythrin and Its Pigment Moiety Phycoerythrobilin, Prepared from Porphyra yezoensis

Abstract

Phycoerythrin from the red alga Porphyra yezoensis has been demonstrated to possess antioxidative activity and is expected to have anti-inflammatory activity. In this study, we examined the effects of phycoerythrin and its pigment moiety, phycoerythrobilin, on the degranulation of mast cells. Phycoerythrin (0.01 mg/mL) and phycoerythrobilin (1 μmol/L) significantly inhibited calcium ionophore (A23187) induced release of β-hexosaminidase from rat basophilic leukemia (RBL-2H3) cells (approximately 50% and 40%, respectively). Phycoerythrobilin significantly suppressed IgE-antigen-stimulated degranulation of RBL-2H3 cells, while phycoerythrin had no effect. A23187-induced degranulation of peritoneal exudate cells (PEC) prepared from rats treated orally with phycoerythrin (4 mg/kg) or phycoerythrobilin (1 μmol/kg) was significantly reduced compared to control PEC. These results suggest that phycoerythrin and phycoerythrobilin exhibit anti-inflammatory activities through the suppression of mast cells degranulation in vivo.