Butyrate Enhances Disease Resistance of Piglets

Dietary substances can manipulate the expression of endogenous host defense peptides (HDPs), which may provide a promising strategy for disease control and prevention, especially for antibiotic-resistant infections. The authors (Haitao Xiong et al., 2015) hypothesized that butyrate can induce HDP expression, which likely contributes to the elimination of Escherichia coli O157:H7 in the intestine and reduces the severity of inflammation caused by E. coli challenge. Piglets treated with or without butyrate (2 g/kg of diet) 2 d before E. coli challenge was employed to investigate the relationship among porcine HDP expression, status of inflammation and E. coli load in feces. The effects of butyrate on HDP gene expression, antibacterial activity of 3D4/2 macrophages and IPEC-1 cells, and phagocytic capacity of 3D4/2 and polymorphonuclear (PMN) leukocytes in vitro were also examined. Results showed that butyrate treatment (1) alleviated clinical symptoms of E. coli -induced hemolytic uremic syndrome and severity of intestine inflammation, (2) significantly reduced E. coli load in feces 24 h after the last inoculation (P< 0.01), (3) significantly up-regulated multiple HDPs in vitro and in vivo, and (4) enhanced the antibacterial activity of macrophage 3D4/2 and IPEC-1 and the phagocytic capacity of 3D4/2 and PMN cells in vitro. Our findings indicate that butyrate enhances disease resistance, promotes clearance of E. coli, and alleviates clinical symptoms of hemolytic uremic syndrome and inflammation partially by affecting endogenous HDP expression