Fumonisin B1 exposure and its selective effect on porcine jejunal segment: Sphingolipids, glycolipids and trans-epithelial passage disturbance

Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium verticillioides, the cause of Fusarium kernel rot in maize. FB1 is toxic in domestic and laboratory animals, including pigs. This study investigated the effects of a seven-days-exposure of 1.5 mg/kg b.w. FB1 on the porcine intestinal epithelium. Statistically significant increases in the ratio of sphinganine to sphingosine, as well as alterations of the glycolipid distribution were observed in the jejunum. Using a porcine intestinal epithelial cell line (IPEC-1) derived from jejunum and ileum, we tested the effect of FB1in vitro in a time- and dose-dependent fashion. A significant increase in sphinganine concentration was observed after 2 days of FB1 exposure at concentrations >100 μM, or from 6 days of FB1 exposure at concentration >20 μM. We were also able to show that FB1 exposure at 200 μM during 16 days increased the intestinal trans-epithelial flux of FB1. These data indicate that, in pigs, this mycotoxin acts selectively on jejunum cells as follows: (i) FB1 affects sphingolipid metabolism, as demonstrated by an increase of the amount of free sphingoid bases in a time- and dose-dependent manner, (ii) a depletion of the glycolipids in plasma membranes is observed, and (iii) an increase occurs in the trans-epithelial flux.