Alternariol mycotoxin affects gut integrity and permeability in porcine epithelial intestinal cell line IPEC-1

Alternariol (AOH) is a mycotoxin produced by fungi belonging to the genus Alternaria, detected in a large variety of commodities such as cereals, fruits, vegetables, beverages, nuts, and other food products. The present study investigates the effect of the mycotoxin alternariol on gut integrity and permeability using an intestinal porcine epithelial cell (IPEC-1) monolayer as a model for intestinal barrier and transport function. Exposure of IPEC-1 cells to higher concentrations of AOH (20 and 50 μg/mL) induced a dose-dependent decrease in cell proliferation, an increase in DNA fragmentation, and a significant increase in LDH activity in porcine intestinal epithelial IPEC-1 cells, indicating an important alteration in the capacity of intestinal epithelial renewal induced by AOH. Higher concentrations of AOH (5 and 10 μg/mL) decreased transepithelial electrical resistance and increased the passage of a fluorophore-conjugated macromolecule, indicating an alteration of the IPEC-1 monolayer integrity and permeability. These alterations are due to a decrease in tight junction proteins and mucins and are associated with an increase in nitric oxide synthesis and a decrease in the levels of pro-inflammatory cytokines IL-6 and IL-8. Taken together, these results showed an important alteration of the gut epithelium with important consequences for pig health. Our results should be confirmed by in vivo trials in swine in order to validate these in vitro findings.