Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs

Fumonisin B1 (FB1) is a mycotoxin which alters intestinal epithelial cell physiology and barrier properties, and accumulates in the colon. Data on effects of FB1 on stress proteins in the gastrointestinal tract (GIT) are lacking. Therefore, we hypothesized that repeated consumption of FB1 alters GIT tissue levels of stress proteins. This was tested using 36 weaned pigs fed a FB1 solution (n = 18) or the vehicle (control; n = 18) for 9 days. The pigs were then slaughtered, the organs were weighed and GIT tissues were collected for assessing GIT integrity, and for analysing stress proteins by Western blotting and densitometry (n = 7 in each group). FB1 had little effects on growth rate but the liver was heavier (P < 0.01) in FB1-fed pigs. αB crystallin and COX-1 concentrations were eight-fold and 12-fold higher in the colon of FB1-fed pigs than in the controls (P < 0.0001). Concentrations of COX-1 and nNOS in the stomach, HSP 70 in the jejunum and HO-2 in the colon were also higher in FB1-fed pigs (P < 0.05 to P < 0.001). In conclusion, the FB1 extract drastically enhanced colonic levels of αB crystallin and COX-1, with milder increases in other stress proteins along the GIT of pigs. The data suggest that the colon is an important target for FB1-induced stress responses.