Hydrolyzed fumonisin B1 induces less inflammatory responses than fumonisin B1 in the co-culture model of porcine intestinal epithelial and immune cells

Abstract

Fumonisin B1 (FB1), mainly produced by Fusarium verticillioides and Fusarium proliferatum, can be converted to the less toxic metabolite hydrolyzed FB1 (HFB1) by enzymatic degradation. The application of an FB1degrading enzyme as a feed additive is a strategy to reduce fumonisin exposure of animals. However, the difference between the effect of FB1 and HFB1 on porcine intestinal immunity is poorly documented. We investigated the toxic effects of FB1 and HFB1 exposure on porcine gut barrier function and intestinal immunity by using a co-culture model of intestinal porcine epithelial cells (IPEC-J2) and porcine peripheral blood mononuclear cells (PBMCs). First, we confirmed that Fusarium mycotoxin (deoxynivalenol; DON), in the presence of an endotoxin (lipopolysaccharide: LPS), disrupted gut permeability of IPEC-J2 and induced inflammatory response in the co-culture system. FB1 induced additional damage to gut barrier function and promoted pro-inflammatory responses in the presence of LPS and DON compared to only LPS/DON treatment. In the co-culture system, FB1/LPS/DON induced increased cell death of PBMCs and pro-inflammatory cytokines than LPS/DON treatment. In contrast, the application of HFB1 resulted in reduced levels of chemokines and pro-inflammatory cytokines together with marginal immune cell death compared to FB1/LPS/DON in the IPEC-J2/PBMC co-culture system. These findings suggest that FB1 aggravates LPS/DON-induced intestinal inflammation, and HFB1 showed less toxicity to immune response. Therefore, enzymatic degradation of FB1 to HFB1 could be an effective strategy to reduce intestinal inflammation in pigs.