Transport of mycotoxins across human gastric NCI–N87 and intestinal Caco-2 cell models

Aflatoxin B1 (AFB1), deoxynivalenol (DON), fumonisin B1 (FB1), and ochratoxin A (OTA) are prevalent mycotoxins co-occurring in food, and their oral intake is conceivable to occur in the gastrointestinal epithelium. The intestinal absorption of some mycotoxins has been studied but only considering their isolated intake, while their gastric absorption in humans has not been explored. This study evaluated the bidirectional in vitro transport of four mycotoxins, isolated and in mixture, across gastric NCI-N87 and intestinal Caco-2 monolayers. AFB1 and DON were bidirectionally transported, more rapidly for AFB1; whereas OTA and FB1 were only transported in the absorptive direction, the first in both monolayers, and the second only in the gastric epithelium. The mixture of four mycotoxins exhibited some differences in cell uptake/excretion ratios. AFB1 presented the highest fraction absorbed (>96%) isolated and in mixture, followed by DON (72.8 and 82.9%); and OTA (11 and 66%) when transported isolated and in mixture, respectively. Different absorptive patterns on both epithelia were found when mycotoxins are transported isolated or in mixture. Further investigation on combined ingestion of toxins and their mixed transport should be considered for the proper evaluation of human absorption and toxicity of those mycotoxins considering their frequent co-occurrence and consequent co-exposure.