Microbial Metabolite Butyrate Suppresses Murine Mast Cell Activation

Background: Mast cell is known for its roles in mediating food allergy and regulating gut inflammation. Butyrate, a major short chain fatty acid produced by gut microbiota, exerts beneficial effects on intestinal homeostasis. However, its role in modulating mast cell function remain undefined. Methods: Murine mastocytoma P815 cells (P815) or murine bone marrow derived mast cells (BMMC) were treated with sodium butyrate (NaB). The proliferation, cell cycle, apoptosis, degranulation and cytokine secretion were assessed. Results: In P815 cells, NaB inhibited cell proliferation, increased acetylation of both histone 3 and α-tubulin. The growth inhibition effect of NaB is probably through reducing c-kit expression and inducing cell cycle arrest and apoptosis, which is indicated by enhanced annexin V/PI staining, caspase-3 and PARP cleavage. In BMMC, NaB treatment dramatically suppressed FceRI dependent TNFα and IL-6 release without affecting degranulation. Furthermore, NaB enhanced histone 3 acetylation but di...