Caffeic Acid Inhibits Degranulation, Cytokine Secretions, and IP3 Receptor 2 Gene Expression in Compound...

Caffeic acid (CA), 3-O-caffeoylquinic acid (3-CQA), and 5-O-caffeoylquinic acid (5-CQA) were subjected to treating stimulated mouse P815 mast cells to unravel their antiallergic potential. β-Hexosaminidase release, appearance, morphology change, cytokine secretions, and degranulation-related pathway gene expressions, including Mas-related G protein-coupled receptor, member B2 (MRGP receptor B2), and inositol 1,4,5-triphosphate receptor 2 (IP3 receptor 2), in the stimulated mast cells were measured. An ELISA was used to determine the secreted cytokines. The relative gene expression folds were analyzed with reverse transcription real-time quantitative polymerase chain reaction. Correlations between gene expressions and different parameters were analyzed using the Pearson product-moment correlation coefficient (r). The results showed that CA had a superior effect than 3-CQA and 5-CQA on reducing β-hexosaminidase release, IL-4, and IL-6 cytokine secretions by the compound 48/80 (C48/80)- and 5-hydroxymethyl-2-furaldehyde (5-HMF)-stimulated mast cells. CA increased intact mast cell numbers but reduced granule releases, evidencing that CA may soothe activated mast cells. CA reduced IP3 receptor 2 gene expression. There were positive correlations between IP3 receptor 2 gene expression and IL-4 and IL-6 cytokine secretions. Our results conclude that CA might inhibit degranulation, IL-4 and IL-6 cytokine secretions, and IP3 receptor 2 gene expression in C48/80-stimulated mouse P815 mast cells.