Toxicity of the emerging mycotoxins beauvericin and enniatins: A mini-review.

Beauvericin and enniatins, emerging mycotoxins produced mainly by Fusarium species, are natural contaminants of cereals and cereal products. These mycotoxins are cyclic hexadepsipeptides with ionophore properties and their toxicity mechanism is related to their ability to transport cations across the cell membrane. Beauvericin and enniatins are cytotoxic, as they decrease cell viability, promote cell cycle arrest, and increase apoptosis and the generation of reactive oxygen species in several cell lines. They also cause changes at the transcriptomic level and have immunomodulatory effects in vitro and in vivo. Toxicokinetic results are scarce, and, despite its proven toxic effects in vitro, no regulation or risk assessment has yet been performed due to a lack of in vivo data. This mini-review aims to report the information available in the literature on studies of in vitro and in vivo toxic effects with beauvericin and enniatins, which are mycotoxins of increasing interest to animal and human health.

Emerging mycotoxins induce hepatotoxicity in pigs' precision-cut liver slices and HepG2 cells.

Emerging mycotoxins are currently gaining more attention due to their high frequency of contamination in foods and grains. However, most data available in the literature are in vitro, with few in vivo results that prevent establishing their regulation. Beauvericin (BEA), enniatins (ENNs), emodin (EMO), apicidin (API) and aurofusarin (AFN) are emerging mycotoxins frequently found contaminating food and there is growing interest in studying their impact on the liver, a key organ in the metabolization of these components. We used an ex vivo model of precision-cut liver slices (PCLS) to verify morphological and transcriptional changes after acute exposure (4 h) to these mycotoxins. The human liver cell line HepG2 was used for comparison purposes. Most of the emerging mycotoxins were cytotoxic to the cells, except for AFN. In cells, BEA and ENNs were able to increase the expression of genes related to transcription factors, inflammation, and hepatic metabolism. In the explants, only ENN B1 led to significant changes in the morphology and expression of a few genes. Overall, our results demonstrate that BEA, ENNs, and API have the potential to be hepatotoxic.

Deoxynivalenol induces apoptosis and inflammation in the liver: Analysis using precision-cut liver slices.

Deoxynivalenol (DON) is one of the most common mycotoxins in cereals and their by-products. Its adverse effects on animal and human health have been extensively studied in the intestine, but little attention has been paid to another target organ for mycotoxins, the liver that is potentially exposed after intestinal absorption and enterohepatic circulation. To assess DON's toxicity in an ex vivo model structurally and physiologically closer to the whole liver, we developed a pig precision-cut liver slices (PCLS) model. PCLS contain all cell types and maintain intercellular and cell-matrix interactions, among other architectural features of the liver. The human HepG2 cell line was used for comparison. We observed that after a short exposure, DON reduced the cell viability of HepG2 cells and induced the expression of genes involved in apoptosis, inflammation and oxidative stress. When PCLS were exposed to DON, damage to the tissues was observed, with no changes in markers of liver function or injury. Exposure to the toxin also triggered liver inflammation and apoptosis, effects already observed in pigs fed DON-contaminated diets. Overall, these data demonstrate that DON had toxic effects on a liver cell line and on whole liver tissue, consistent with the effect observed during in vivo exposure. They also indicate that pig PCLS is a relevant and sensitive model to investigate the liver toxicity of food contaminants.