Impact of Deoxynivalenol and Zearalenone as Single and Combined Treatment on DNA, Cell Cycle and Cell Proliferation in HepG2 Cells

Deoxynivalenol triggers mitotic catastrophe and apoptosis in C2C12 myoblasts

Deoxynivalenol (DON), commonly known as vomitoxin, is a mycotoxin produced by fungi and is frequently found as a contaminant in various cereal-based food worldwide. While the harmful effects of DON have been extensively studied in different tissues, its specific impact on the proliferation of skeletal muscle cells remains unclear. In this study, we utilized murine C2C12 myoblasts as a model to explore the influence of DON on their proliferation. Our observations indicated that DON exhibits dose-dependent toxicity, significantly inhibiting the proliferation of C2C12 cells. Through the application of RNA-seq analysis combined with gene set enrichment analysis, we identified a noteworthy downregulation of genes linked to the extracellular matrix (ECM) and condensed chromosome. Concurrently with the reduced expression of ECM genes, immunostaining analysis revealed notable changes in the distribution of fibronectin, a vital ECM component, condensing into clusters and punctate formations. Remarkably, the exposure to DON induced the formation of multipolar spindles, leading to the disruption of the normal cell cycle. This, in turn, activated the p53-p21 signaling pathway and ultimately resulted in apoptosis. These findings contribute significant insights into the mechanisms through which DON induces toxicity within skeletal muscle cells.

Low Doses of Deoxynivalenol and Zearalenone Alone or in Combination with a Mycotoxin Binder Affect ABCB1 mRNA and ABCC2 mRNA Expression in the Intestines of Pigs

Mycotoxin binders, in combination with enzymes degrading some mycotoxins, contribute to feed detoxification. Their use reduces economic losses and the negative impacts of mycotoxins on animal health and productivity in farm animals. The aim of this study was to evaluate the efficacy of a mycotoxin detoxifier on the expression of the ATP-binding cassette efflux transporters ABCB1 mRNA and ABCC2 mRNA, which transport xenobiotics and thus have a barrier function, in the tissues of pigs exposed to low doses of deoxynivalenol (DON, 1 mg/kg feed) and zearalenone (ZEN, 0.4 mg/kg feed) for 37 days. The levels of expression were determined by an RT-PCR, and the effect of the mycotoxin detoxifier (Mycofix Plus3.E) was evaluated by a comparison of results between healthy pigs (n = 6), animals treated with DON and ZEN (n = 6), and a group that received both mycotoxins and the detoxifier (n = 6). A significant downregulation of ABCB1 mRNA and ABCC2 mRNA was observed in the jejunum (p < 0.05). A tendencies toward the downregulation of ABCB1 mRNA and ABCC2 mRNA were found in the ileum and duodenum, respectively. The mycotoxin detoxifier restored the expression of ABCB1 mRNA to the level found in healthy animals but did not restore that of ABCC2 mRNA to the level of healthy animals in the jejunum.

Identification of the hub genes linked to zearalenone-induced hepatotoxicity in broiler chickens

Zearalenone (ZEN) is a mycotoxin found in food and feed that impairs the function of multiple organs, especially the liver. However, the specific mechanisms through which ZEN induces liver damage in broiler chickens are not well understood. Therefore, this study aimed to identify the key genes linked to the hepatotoxicity induced by ZEN exposure in broiler chickens. Gene expression data from ZEN-treated and control chicken embryo primary hepatocytes (CEPHs) were used to implement differential expression analysis. Totally, 436 differentially expressed genes (DEGs) were detected, in which 223 and 213 genes were up- and down-regulated in ZEN-treated CEPHs, respectively. Gene ontology analysis suggested that these DEGs were involved in various biological processes, including chromosome segregation, mitotic cytokinesis, mitotic cell cycle, cell division, and mitotic spindle organization. Pathway analysis showed that the DEGs were associated with p53, FoxO, ubiquitin-mediated proteolysis, cell cycle, and mismatch repair signaling pathways. Furthermore, the hub genes, including BRCA1, CDC45, CDCA3, CDKN3, CENPE, CENPF, CENPI, CENPM, CENPU, and CEP55, potentially contributed to ZEN-induced hepatotoxicity. In conclusion, our study provides the valuable insight into the mechanism underlying ZEN-induced hepatotoxicity in broiler chickens.

DON induced DNA damage triggers absence of p53-mediated G2 arrest and apoptosis in IPEC-1 cells

Deoxynivalenol (DON) stands among the prevalent mycotoxins, and usually contaminates cereal foods and animal feed, leading to human and animal clinical poisoning symptoms such as abdominal pain, diarrhea, and vomiting. To date, the mechanism of toxicity of DON in different mammalian cells is not fully elucidated. In this study, we explored the detrimental impacts of DON on porcine intestinal epithelial cells (IPEC-1), serving as a representative model for porcine intestinal epithelial cells. After treating cells with DON for 24 h, DON can significantly inhibit the activity of cells, induce the production of reactive oxygen species (ROS), significantly reduce the content of glutathione and the activity of catalase, and increase the activity of superoxide dismutase and malondialdehyde, leading to an imbalance in intracellular redox status. In addition, DON can induce DNA double-strand breaks, and decrease mitochondrial membrane potential. Furthermore, DON can promote the release of Cyt C through changes in mitochondrial permeability through inhibit the expression of B-cell lymphoma 2 (Bcl-2) proteins, leading to apoptosis through the mitochondrial pathway. On the other hand, we found that DON can cause IPEC-1 cells G2 phase cycle arrest. Different with our pervious study, DON induces cell cycle arrest in the G2 phase only by activating the ATM-Chk2-Cdc 25 C pathway, but cannot regulate the cell cycle arrest via the ATM-p53 pathway. These results indicate that DON can induce the same toxic phenotype in different cells, but its toxic mechanism is different. All these provide a rationale for revealing DON induced cytotoxicity and intestinal diseases.

Resveratrol protects against deoxynivalenol-induced ferroptosis in HepG2 cells

Deoxynivalenol (DON) is one of the most serious mycotoxins that contaminate food and feed, causing hepatocyte death. However, there is still a lack of understanding regarding the new cell death modalities that explain DON-induced hepatocyte toxicity. Ferroptosis is an iron-dependent type of cell death. The aim of this study was to explore the role of ferroptosis in DON-exposed HepG2 cytotoxicity and the antagonistic effect of resveratrol (Res) on its toxicity, and the underlying molecular mechanisms. HepG2 cells were treated with Res (8μM) or/and DON (0.4μM) for 12hours. We examined cell viability, cell proliferation, expression of ferroptosis-related genes, levels of lipid peroxidation and Fe(II). The results revealed that DON reduced the expression levels of GPX4, SLC7A11, GCLC, NQO1, and Nrf2 while promoting the expression of TFR1, GSH depletion, accumulation of MDA and total ROS. DON enhanced production of 4-HNE, lipid ROS and Fe(II) overload, resulting in ferroptosis. However, pretreatment with Res reversed these changes, attenuating DON-induced ferroptosis, improving cell viability and cell proliferation. Importantly, Res prevented Erastin and RSL3-induced ferroptosis, suggesting that Res exerted an anti-ferroptosis effect by activating SLC7A11-GSH-GPX4 signaling pathways. In summary, Res ameliorated DON-induced ferroptosis in HepG2 cells. This study provides a new perspective on the mechanism of DON-induced hepatotoxicity formation, and Res may be an effective drug to alleviate DON-induced hepatotoxicity.