Evaluation of Cross-Talk and Alleviate Potential of Cytotoxic Factors Induced by Deoxynivalenol in IPEC-J2 Cells Interference with Curcumin.

Deoxynivalenol (DON) is a mycotoxin produced by Fusarium graminearum, and curcumin (CUR) is a natural polyphenolic compound found in turmeric. However, the combined treatment of CUR and DON to explore the mitigating effect of CUR on DON and their combined mechanism of action is not clear. Therefore, in this study, we established four treatment groups (CON, CUR, DON and CUR + DON) to investigate their mechanism in the porcine intestinal epithelial cells (IPEC-J2). In addition, the cross-talk and alleviating potential of CUR interfering with DON-induced cytotoxic factors were evaluated by in vitro experiments; the results showed that CUR could effectively inhibit DON-exposed activated TNF-α/NF-κB pathway, attenuate DON-induced apoptosis, and alleviate DON-induced endoplasmic reticulum stress and oxidative stress through PERK/CHOP pathways, which were verified at both mRNA and protein levels. In conclusion, these promising findings may contribute to the future use of CUR as a novel feed additive to protect livestock from the harmful effects of DON.

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.

Deoxynivalenol Induces Drp-1-Mediated Mitochondrial Dysfunction via Elevating Oxidative Stress.

Mitochondrial dysfunction is often linked to neurotoxicity and neurological diseases and stems from oxidative stress, yet effective therapies are lacking. Deoxynivalenol (DON or vomitoxin) is one of the most common and hazardous type-B trichothecene mycotoxins, which contaminates crops used for food and animal feed. Despite the abundance of preliminary reports, comprehensive investigations are scarce to explore the relationship between these fungal metabolites and neurodegenerative disorders. The present study aimed to elucidate the precise role of DON in mitochondrial dynamics and cell death in neuronal cells. Excessive mitochondrial fission is associated with the pathology of several neurodegenerative diseases. Human SH-SY5Y cells were treated with different concentrations of DON (250-1000 ng/mL). Post 24 and 48 h DON treatment, the indexes were measured as follows: generation of reactive oxygen species (ROS), ATP levels, mitochondrial membrane potential, calcium levels, and cytotoxicity in SH-SY5Y cells. The results showed that cytotoxicity, intracellular calcium levels, and ROS in the DON-treated group increased, while the ATP levels and mitochondrial membrane potential decreased in a dose-dependent manner. With increasing DON concentrations, the expression levels of P-Drp-1, mitochondrial fission proteins Mff, and Fis-1 were elevated with reduced activities of MFN1, MFN2, and OPA1, further resulting in an increased expression of autophagic marker LC3 and beclin-1. The reciprocal relationship between mitochondrial damage and ROS generation is evident as ROS can instigate structural and functional deficiencies within the mitochondria. Consequently, the impaired mitochondria facilitate the release of ROS, thereby intensifying the cycle of damage and exacerbating the overall process. Using specific hydroxyl, superoxide inhibitors, and calcium chelators, our study confirmed that ROS and Ca2+-mediated signaling pathways played essential roles in DON-induced Drp1 phosphorylation. Therefore, ROS and mitochondrial fission inhibitors could provide critical research tools for drug development in mycotoxin-induced neurodegenerative diseases.

Are Infants and Children at Risk of Adverse Health Effects from Dietary Deoxynivalenol Exposure? An Integrative Review.

Deoxynivalenol (DON) is a foodborne mycotoxin produced by Fusarium molds that commonly infect cereal grains. It is a potent protein synthesis inhibitor that can significantly impact humans' gastrointestinal, immune, and nervous systems and can alter the microbiome landscape. Low-dose, chronic exposure to DON has been found to stimulate the immune system, inhibit protein synthesis, and cause appetite suppression, potentially leading to growth failure in children. At higher doses, DON has been shown to cause immune suppression, nausea, vomiting, abdominal pain, headache, diarrhea, gastroenteritis, the malabsorption of nutrients, intestinal hemorrhaging, dizziness, and fever. A provisional maximum tolerable daily intake (PMTDI) limit of 1 µg/kg/body weight has been established to protect humans, underscoring the potential health risks associated with DON intake. While the adverse effects of dietary DON exposure have been established, healthcare communities have not adequately investigated or addressed this threat to child health, possibly due to the assumption that current regulatory exposure limits protect the public appropriately. This integrative review investigated whether current dietary DON exposure rates in infants and children regularly exceed PMTDI limits, placing them at risk of negative health effects. On a global scale, the routine contamination of cereal grains, bakery products, pasta, and human milk with DON could lead to intake levels above PMTDI limits. Furthermore, evidence suggests that other food commodities, such as soy, coffee, tea, dried spices, nuts, certain seed oils, animal milk, and various water reservoirs, can be intermittently contaminated, further amplifying the scope of the issue. Better mitigation strategies and global measures are needed to safeguard vulnerable youth from this harmful toxicant.

Attempting to Create a Pathway to 15-Deacetylcalonectrin with Limited Accumulation in Cultures of Fusarium Tri3 Mutants: Insight into Trichothecene Biosynthesis Machinery.

The compound 15-deacetylcalonectrin (15-deCAL) is a common pathway intermediate in the biosynthesis of Fusarium trichothecenes. This tricyclic intermediate is metabolized to calonectrin (CAL) by trichothecene 15-O-acetyltransferase encoded by Tri3. Unlike other trichothecene pathway Tri gene mutants, the Δtri3 mutant produces lower amounts of the knocked-out enzyme's substrate 15-deCAL, and instead, accumulates higher quantities of earlier bicyclic intermediate and shunt metabolites. Furthermore, evolutionary studies suggest that Tri3 may play a role in shaping the chemotypes of trichothecene-producing Fusarium strains. To better understand the functional role of Tri3p in biosynthesis and evolution, we aimed to develop a method to produce 15-deCAL by using transgenic Fusarium graminearum strains derived from a trichothecene overproducer. Unfortunately, introducing mutant Tri3, encoding a catalytically impaired but structurally intact acetylase, did not improve the low 15-deCAL production level of the ΔFgtri3 deletion strain, and the bicyclic products continued to accumulate as the major metabolites of the active-site mutant. These findings are discussed in light of the enzyme responsible for 15-deCAL production in trichothecene biosynthesis machinery. To efficiently produce 15-deCAL, we tested an alternative strategy of using a CAL-overproducing transformant. By feeding a crude CAL extract to a Fusarium commune strain that was isolated in this study and capable of specifically deacetylating C-15 acetyl, 15-deCAL was efficiently recovered. The substrate produced in this manner can be used for kinetic investigations of this enzyme and its possible role in chemotype diversification.

Hesperidin Alleviates Hepatic Injury Caused by Deoxynivalenol Exposure through Activation of mTOR and AKT/GSK3ß/TFEB Pathways.

Deoxynivalenol (DON) is a common agricultural mycotoxin that is chemically stable and not easily removed from cereal foods. When organisms consume food made from contaminated crops, it can be hazardous to their health. Numerous studies in recent years have found that hesperidin (HDN) has hepatoprotective effects on a wide range of toxins. However, few scholars have explored the potential of HDN in attenuating DON-induced liver injury. In this study, we established a low-dose DON exposure model and intervened with three doses of HDN, acting on male C57 BL/6 mice and AML12 cells, which served as in vivo and in vitro models, respectively, to investigate the protective mechanism of HDN against DON exposure-induced liver injury. The results suggested that DON disrupted hepatic autophagic fluxes, thereby impairing liver structure and function, and HDN significantly attenuated these changes. Further studies revealed that HDN alleviated DON-induced excessive autophagy through the mTOR pathway and DON-induced lysosomal dysfunction through the AKT/GSK3ß/TFEB pathway. Overall, our study suggested that HDN could ameliorate DON-induced autophagy flux disorders via the mTOR pathway and the AKT/GSK3ß/TFEB pathway, thereby reducing liver injury.

Detoxification of DON-induced hepatotoxicity in mice by cold atmospheric plasma.

Deoxynivalenol (DON) is one of the most common mycotoxins distributed in food and feed, which causes severe liver injury in humans and animals. Cold atmospheric plasma (CAP) has received much attention in mycotoxin degradation due to the advantages of easy operation, high efficiency, and low temperature. So far, the majority of studies have focused on the degradation efficiency and mechanism of CAP on DON, while there is still little information available on the hepatotoxicity of DON after CAP treatment. Herein, this study aimed to investigate the effect of CAP on DON-induced hepatotoxicity both in vitro and in vivo and its underlying mechanisms. The results showed that 120-s CAP treatment achieved 97 % degradation of DON. The vitro hepatotoxicity of DON in L02 cells was significantly reduced with CAP treatment time. Meanwhile, CAP markedly alleviated DON-induced liver injury in mice including the balloon-like degeneration of liver tissues and elevation of AST and ALP level. The underlying mechanism for CAP detoxification of DON-induced hepatotoxicity was further elucidated. The results showed that DON caused severe oxidative stress in cells by suppressing the antioxidant signaling pathway of Nrf2/HO-1/NQO-1, consequently leading to mitochondrial dysfunction and cell apoptosis, accompanied by cellular senescence and inflammation. CAP blocked DON inhibition on the Nrf2/HO-1/NQO-1 signaling pathway through the efficient degradation of DON, accordingly alleviating the oxidative stress and liver injury induced by DON. Therefore, CAP is an effective method to eliminate DON hepatotoxicity, which can be applied in the detoxification of mycotoxin-contaminated food and feed to ensure human and animal health.

The trichothecene mycotoxin deoxynivalenol facilitates cell-to-cell invasion during wheat-tissue colonization by Fusarium graminearum.

Fusarium head blight disease on small-grain cereals is primarily caused by the ascomycete fungal pathogen Fusarium graminearum. Infection of floral spike tissues is characterized by the biosynthesis and secretion of potent trichothecene mycotoxins, of which deoxynivalenol (DON) is widely reported due to its negative impacts on grain quality and consumer safety. The TRI5 gene encodes an essential enzyme in the DON biosynthesis pathway and the single gene deletion mutant, ΔTri5, is widely reported to restrict disease progression to the inoculated spikelet. In this study, we present novel bioimaging evidence revealing that DON facilitates the traversal of the cell wall through plasmodesmata, a process essential for successful colonization of host tissue. Chemical complementation of ΔTri5 did not restore macro- or microscopic phenotypes, indicating that DON secretion is tightly regulated both spatially and temporally. A comparative qualitative and quantitative morphological cellular analysis revealed infections had no impact on plant cell wall thickness. Immunolabelling of callose at plasmodesmata during infection indicates that DON can increase deposits when applied exogenously but is reduced when F. graminearum hyphae are present. This study highlights the complexity of the interconnected roles of mycotoxin production, cell wall architecture and plasmodesmata in this highly specialized interaction.

A novel yeast-based biosensor for the quick determination of Deoxynivalenol.

Mycotoxins are commonly found in food materials and severely threaten human health. Antibodies play a key role as a part of immunological techniques in detecting mycotoxins. Therefore, highly specific antibodies and detection techniques against mycotoxins need to be developed for advancements in medical research. In this study, we presented a novel strategy for quickly screening highly specific antigen-binding fragment (Fab) antibodies based on yeast surface display (YSD) and detecting small-molecule compounds based on a YSD biosensor. We constructed a yeast surface display Deoxynivalenol (DON)-Fab library with 105 cfu/mL with a galactose-inducible bidirectional promoter. By conducting efficient magnetic-activated cell sorting and fluorescence-activated cell sorting (MACS/FACS), four kinds of DON-selective yeasts were screened. As Fab@YSD C4# showed high sensitivity, we used it to build a one-pot Fab@YSD chemiluminescence biosensor with DON-BSA@Biotin and Streptavidin-alkaline phosphatase (SA-ALP). This method showed a low operational threshold (LOD = 0.166 pg/mL) and a high population range (linear range = 0.001-132.111 ng/mL) within 40 min, which facilitated the detection of DON with high specificity and better recovery in real samples (wheat, corn, flour, and cornmeal). Our results suggested that the Fab@YSD chemiluminescence biosensor is an inexpensive, reproducible, user-friendly, and sensitive method for detecting DON and may be used to quickly detect other small-molecule contaminants in food items.

Velvet Family Protein FpVelB Affects Virulence in Association with Secondary Metabolism in Fusarium pseudograminearum.

Fusarium pseudograminearum causes destructive crown disease in wheat. The velvet protein family is a crucial regulator in development, virulence, and secondary metabolism of fungi. We conducted a functional analysis of FpVelB using a gene replacement strategy. The deletion of FpVelB decreased radial growth and enhanced conidial production compared to that of wild type. Furthermore, FpVelB modulates the fungal responses to abiotic stress through diverse mechanisms. Significantly, virulence decreased after the deletion of FpVelB in both the stem base and head of wheat. Genome-wide gene expression profiling revealed that the regulation of genes by FpVelB is associated with several processes related to the aforementioned phenotype, including "immune", "membrane", and "antioxidant activity", particularly with regard to secondary metabolites. Most importantly, we demonstrated that FpVelB regulates pathogen virulence by influencing deoxynivalenol production and modulating the expression of the PKS11 gene. In conclusion, FpVelB is crucial for plant growth, asexual development, and abiotic stress response and is essential for full virulence via secondary metabolism in F. pseudograminearum.

Deoxynivalenol induces m6A-mediated upregulation of p21 and growth arrest of mouse hippocampal neuron cells in vitro.

Hippocampal neurons maintain the ability of proliferation throughout life to support neurogenesis. Deoxynivalenol (DON) is a mycotoxin that exhibits brain toxicity, yet whether and how DON affects hippocampal neurogenesis remains unknown. Here, we use mouse hippocampal neuron cells (HT-22) as a model to illustrate the effects of DON on neuron proliferation and to explore underlying mechanisms. DON exposure significantly inhibits the proliferation of HT-22 cells, which is associated with an up-regulation of cell cycle inhibitor p21 at both mRNA and protein levels. Global and site-specific m6A methylation levels on the 3'UTR of p21 mRNA are significantly increased in response to DON treatment, whereas inhibition of m6A hypermethylation significantly alleviates DON-induced cell cycle arrest. Further mechanistic studies indicate that the m6A readers YTHDF1 and IGF2BP1 are responsible for m6A-mediated increase in p21 mRNA stability. Meanwhile, 3'UTR of E3 ubiquitin ligase TRIM21 mRNA is also m6A hypermethylated, and another m6A reader YTHDF2 binds to the m6A sites, leading to decreased TRIM21 mRNA stability. Consequently, TRIM21 suppression impairs ubiquitin-mediated p21 protein degradation. Taken together, m6A-mediated upregulation of p21, at both post-transcriptional and post-translational levels, contributes to DON-induced inhibition of hippocampal neuron proliferation. These results may provide new insights for epigenetic therapy of neurodegenerative diseases.

Necroptosis contributes to the intestinal toxicity of deoxynivalenol and is mediated by methyltransferase SETDB1.

Deoxynivalenol (DON) is a secondary metabolite produced by fungi, which causes serious health issues worldwide due to its widespread presence in human and animal diets. Necroptosis is a newly proposed cell death mode and has been proposed as a potential mechanism of intestinal disease. This study aimed to investigate the role of necroptosis in intestinal damage caused by DON exposure. Piglets were fed diets with or without 4 mg/kg DON for 3 weeks or given a gavage of 2 mg/kg BW DON or sterile saline to investigate the effects of chronic or acute DON exposure on the gut, respectively. IPEC-1 cells were challenged with different concentrations of DON to investigate the effect of DON exposure on the intestinal epithelial cells (IECs) in vitro. Subsequently, the inhibitors of necroptosis were used to treat cells or piglets prior to DON challenge. Chronic and acute DON exposure both caused morphological damage, reduction of disaccharidase activity, decrease of tight junction protein expression, inflammation of the small intestine, and necroptosis of intestinal epithelial cells in piglets. Necroptosis was also detected when IPEC-1 cell damage was induced by DON in vitro. The suppression of necroptosis in IPEC-1 cells by inhibitors (necrostatin-1 (Nec-1), GSK'872, or GW806742X) alleviated cell death, the decrease of tight junction protein expression, oxidative stress, and the inflammatory response induced by DON. Furthermore, pre-treatment with Nec-1 in piglets was also observed to protect the intestine against DON-induced enterotoxicity. Additionally, the expression of histone methyltransferase SETDB1 was abnormally downregulated upon chronic and acute DON exposure in piglets, and necroptosis was activated in IPEC-1 cells due to knockout of SETDB1. Collectively, these results demonstrate that necroptosis of IECs is a mechanism of DON-induced enterotoxicity and SETDB1 mediates necroptosis upon DON exposure in IECs, suggesting the potential for targeted inhibition of necroptosis to alleviate mycotoxin-induced enterotoxicity and intestinal disease.

Effects of hesperidin on mitochondrial function, mitochondria-associated endoplasmic reticulum membranes and IP3R-MCU calcium axis in the intestine of piglets exposed to deoxynivalenol.

Deoxynivalenol (DON) pollution is prevalent in crops, and can induce oxidative stress and intestinal injury. Hesperidin is one of the major flavonoids in citrus fruits that has various biological activities such as antioxidant and anti-inflammatory activities. However, whether hesperidin could alleviate DON-induced intestinal injury and the mechanism remain unclear. Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) have attracted attention for their crucial signaling points to regulate ER-mitochondria calcium transfer. This study aims to evaluate the effects of hesperidin on the intestinal barrier, mitochondrial function, MAMs, and inositol 1,4,5-triphosphate receptor (IP3R)-mitochondrial calcium uniporter (MCU) calcium axis in the intestine of piglets exposed to DON. Twenty-four piglets were randomly divided into four groups in a 2 × 2 factorial arrangement for a 21-d experiment: Control: basal diet; hesperidin group: basal diet + 300 mg kg-1 hesperidin; DON: basal diet + 1.5 mg kg-1 DON; DON + hesperidin group: basal diet + 1.5 mg kg-1 DON + 300 mg kg-1 hesperidin. The data showed that when compared with the DON group, hesperidin improved growth performance and the intestinal barrier, alleviated intestinal oxidative stress and ER stress, and decreased the serum alanine aminotransferase (ALT) level (P < 0.05). Hesperidin also alleviated mitochondrial dysfunction and ferroptosis in the intestine of piglets exposed to DON (P < 0.05). Importantly, hesperidin prevented excessive MAM formation by downregulating the protein levels of Mitofusin 2 (Mfn2) and glucose-regulated protein 75 (GRP75), decreasing the ratio of the mitochondria with MAMs/total mitochondria and the ratio of MAM length/mitochondrial perimeter and lengthening the mitochondria-ER distance in MAMs (P < 0.05). Furthermore, hesperidin regulated the IP3R-glucose-regulated protein 75 (GRP75)-voltage-dependent anion channel 1 (VDAC1)-MCU calcium axis by decreasing the protein levels of GRP75 and MCU and the calcium level of the mitochondria compared with the DON group (P < 0.05). An in vitro experiment was conducted to further explore whether IP3R-mediated ER-mitochondria calcium transfer was involved in the protective effects of hesperidin on the intestinal epithelium barrier and mitochondria. Data showed that hesperidin may exert protective effects on the intestinal epithelium barrier and mitochondria via inhibiting ER-mitochondrial calcium transfer mediated by IP3Rs. These data suggested that hesperidin could alleviate MAM-mediated mitochondrial calcium overload, thereby improving mitochondrial function and alleviating oxidative stress and intestinal injury in DON-challenged piglets.

Smartphone-enabled colorimetric immunoassay for deoxynivalenol based on Mn2+-mediated aggregation of AuNPs.

Deoxynivalenol (DON) is a common mycotoxin in food that mainly pollutes grain crops and feeds, such as barley, wheat and corn. DON has caused widespread concern in the field of food and feed safety. In this study, a colorimetric immunoassay was proposed based on the aggregation of gold nanoparticles (AuNPs) due to the decomposition of Mn2+ from gold-coated manganese dioxide (AuNP@MnO2) nanosheets. In this study, 2-(dihydrogen phosphate)-l-ascorbic acid (AAP) was hydrolyzed by alkaline phosphatase (ALP) and converted to ascorbic acid (AA). Then, AuNP@MnO2 was reduced to Mn2+ and AuNPs aggregation occurred. Using the unique optical characteristics of AuNPs and AuNP@MnO2, visible color changes realized simple detection of DON with high sensitivity and portability. With increasing DON content, the color changed more obviously. To quantitatively detect DON, pictures can be taken and the blue value can be read by a smartphone. The detection limit (Ic10) of this method was 0.098 ng mL-1, which was 326 times higher than that of traditional competitive ELISA, and the detection range was 0.177-6.073 ng mL-1. This method exhibited high specificity with no cross-reaction in other structural analogs. The average recovery rate of DON in corn flour samples was 89.1 %-110.2 %, demonstrating the high accuracy and stability of this assay in actual sample detection. Therefore, the colorimetric immunoassay can be used for DON-related food safety monitoring.

Maternal exposure to DON during lactation induces testicular toxicity in pubertal and adult offspring mice.

Deoxynivalenol (DON), a type B trichothecene mycotoxin, commonly occurs in cereal grains, and poses significant health risks to humans and animals. Numerous studies reveal its obvious toxic effects on male reproductive performance as well as its ability to transfer from the lactating mother to the suckling offspring through colostrum and milk. The objective of this study was to evaluate the toxic effect of lactational DON exposure on testicular morphology, hormonal levels, inflammation, apoptosis and proliferation of germ cells, tight junction, and sperm quality in male offspring. Sixty-six male offspring mice from lactating dams exposed to DON were euthanized at PND 21 and PND 70 to investigate the reproductive toxicity. Our results indicated that maternal DON exposure had a significant impact on the weight and volume of the testes, caused testicular histopathology, and reduced testosterone levels by downregulating expressions of StAR, CYP11A1, and CYP17A1 in male offspring. We also found that maternal DON exposure led to testicular inflammation in male offspring, which was attributed to increased levels of inflammatory markers, including IL-1ß, IL-6, TNF-α, and IFN-γ. Maternal DON exposure resulted in impaired tight junctions of Sertoli cells in male offspring, as evidenced by decreased expressions of ZO-1, Occludin, and Claudin-3. In addition, maternal DON exposure caused a reduction in the number of Sertoli cells and germ cells, ultimately leading to decreased sperm count and quality in adult male offspring. Collectively, these findings provide compelling evidence that maternal exposure to DON during lactation causes testicular toxicity in both pubertal and adult male offspring.

No-observed adverse effect levels of deoxynivalenol and aflatoxin B1 in combination induced immune inhibition and apoptosis in vivo and in vitro.

Mycotoxins are toxic metabolites produced by fungal species, commonly exist in animal feeds, and pose a serious risk to human as well as animal health. But limited studies have focused on combined effects of no-observed adverse effect levels. In vivo study, 6 weeks old twenty-four mice were individually exposed to Deoxynivalenol (DON) at 0.1 mg/kg BW, Aflatoxin B1 (AFB1) at 0.01 mg/kg BW, and mixture of DON and AFB1 (0.1 mg/kg BW and 0.01 mg/kg BW, respectively) for 28 days. Then, DON at 0.5 µg/mL, AFB1 at 0.04 µg/mL, and mixtures of DON and AFB1 (0.5 µg/mL, 0.04 µg/mL, respectively) were applied to porcine alveolar macrophages (PAMs) in vitro study. Our in vivo results revealed that the combined no-observed adverse effect levels of DON and AFB1 administration decreased IgA and IgG levels in the serum, the splenic TNF-α, IFN-γ, IL-2 and IL-6 mRNA expression and T-lymphocyte subset levels (CD4+ and CD8+) in the spleen. Additionally, the combined administration increased caspase-3, caspase-9, Bax, Cyt-c, and decreased Bcl-2 protein expression. Taken together, the combined no-observed adverse effect levels of DON and AFB1 could induce immunosuppression, which may be related to apoptosis. This study provides new insights into the combined immune toxicity (DON and AFB1).

FpPEX5 and FpPEX7 are involved in the growth, reproduction, DON toxin production, and pathogenicity in Fusarium pseudograminearum.

Fusarium crown rot, caused by Fusarium pseudograminearum, is a devastating disease affecting the yield and quality of cereal crops. Peroxisomes are single-membrane organelles that play a critical role in various biological processes in eukaryotic cells. To functionally characterise peroxisome biosynthetic receptor proteins FpPEX5 and FpPEX7 in F. pseudograminearum, we constructed deletion mutants, ΔFpPEX5 and ΔFpPEX7, and complementary strains, ΔFpPEX5-C and ΔFpPEX7-C, and analysed the functions of FpPEX5 and FpPEX7 proteins using various phenotypic observations. The deletion of FpPEX5 and FpPEX7 resulted in a significant deficiency in mycelial growth and conidiation and blocked the peroxisomal targeting signal 1 and peroxisomal targeting signal 2 pathways, which are involved in peroxisomal matrix protein transport, increasing the accumulation of lipid droplets and reactive oxygen species. The deletion of FpPEX5 and FpPEX7 may reduce the formation of toxigenic bodies and decrease the pathogenicity of F. pseudograminearum. These results indicate that FpPEX5 and FpPEX7 play vital roles in the growth, asexual reproduction, virulence, and fatty acid utilisation of F. pseudograminearum. This study provides a theoretical basis for controlling stem rot in wheat.

The ING protein Fng2 associated with RPD3 HDAC complex for the regulation of fungal development and pathogenesis in wheat head blight fungus.

ING proteins display a high level of evolutionary conservation across various species, and play a crucial role in modulating histone acetylation levels, thus regulating various important biological processes in yeast and humans. Filamentous fungi possess distinct biological characteristics that differentiate them from yeasts and humans, and the specific roles of ING proteins in filamentous fungi remain largely unexplored. In this study, an ING protein, Fng2, orthologous to the yeast Pho23, has been identified in the wheat head blight fungus Fusarium graminearum. The deletion of the FNG2 gene resulted in defects in vegetative growth, conidiation, sexual reproduction, plant infection, and deoxynivalenol (DON) biosynthesis. Acting as a global regulator, Fng2 exerts negative control over histone H4 acetylation and governs the expression of over 4000 genes. Moreover, almost half of the differentially expressed genes in the fng3 mutant were found to be co-regulated by Fng2, emphasizing the functional association between these two ING proteins. Notably, the fng2 fng3 double mutant exhibits significantly increased H4 acetylation and severe defects in both fungal development and pathogenesis. Furthermore, Fng2 localizes within the nucleus and associates with the FgRpd3 histone deacetylase (HDAC) to modulate gene expression. Overall, Fng2's interaction with FgRpd3, along with its functional association with Fng3, underscores its crucial involvement in governing gene expression, thereby significantly influencing fungal growth, asexual and sexual development, pathogenicity, and secondary metabolism.

Pyrroloquinoline quinone production defines the ability of Devosia species to degrade deoxynivalenol.

Deoxynivalenol (DON) is a prevalent mycotoxin that primarily contaminates cereal crops and animal feed, posing a significant risk to human and animal health. In recent years, an increasing number of Devosia strains have been identified as DON degradation bacteria, and significant efforts have been made to explore their potential applications in the food and animal feed industries. However, the characteristics and mechanisms of DON degradation in Devosia strains are still unclear. In this study, we identified a novel DON degrading bacterium, Devosia sp. D-G15 (D-G15), from soil samples. The major degradation products of DON in D-G15 were 3-keto-DON, 3-epi-DON and an unidentified product, compound C. The cell viability assay showed that the DON degradation product of D-G15 revealed significantly reduced toxicity to HEK293T cells compared to DON. Three enzymes for DON degradation were further identified, with G15-DDH converting DON to 3-keto-DON and G15-AKR1/G15-AKR6 reducing 3-keto-DON to 3-epi-DON. Interestingly, genome comparison of Devosia strains showed that the pyrroloquinoline quinone (PQQ) synthesis gene cluster is a unique feature of DON degradation strains. Subsequently, adding PQQ to the cultural media of Devosia strains without PQQ synthesis genes endowed them with DON degradation activity. Furthermore, a novel DON-degrading enzyme G13-DDH (<30% homology with known DON dehydrogenase) was identified from a Devosia strain that lacks PQQ synthesis ability. In summary, a novel DON degrading Devosia strain and its key enzymes were identified, and PQQ production was found as a distinct feature among Devosia strains with DON degradation activity, which is important for developing Devosia strain-based technology in DON detoxification.

An Algoclay-Based Decontaminant Decreases Exposure to Aflatoxin B1, Ochratoxin A, and Deoxynivalenol in a Toxicokinetic Model, as well as Supports Intestinal Morphology, and Decreases Liver Oxidative Stress in Broiler Chickens Fed a Diet Naturally Contaminated with Deoxynivalenol.

The aims of this study were (i) to determine the effect of an algoclay-based decontaminant on the oral availability of three mycotoxins (deoxynivalenol; DON, ochratoxin A; OTA, and aflatoxin B1; AFB1) using an oral bolus model and (ii) to determine the effect of this decontaminant on the performance, intestinal morphology, liver oxidative stress, and metabolism, in broiler chickens fed a diet naturally contaminated with DON. In experiment 1, sixteen 27-day-old male chickens (approximately 1.6 kg body weight; BW) were fasted for 12 h and then given a bolus containing either the mycotoxins (0.5 mg DON/kg BW, 0.25 mg OTA/kg BW, and 2.0 mg AFB1/kg BW) alone (n = 8) or combined with the decontaminant (2.5 g decontaminant/kg feed; circa 240 mg/kg BW) (n = 8). Blood samples were taken between 0 h (before bolus administration) and 24 h post-administration for DON-3-sulphate, OTA, and AFB1 quantification in plasma. The algoclay decontaminant decreased the relative oral bioavailability of DON (39.9%), OTA (44.3%), and AFB1 (64.1%). In experiment 2, one-day-old male Ross broilers (n = 600) were divided into three treatments with ten replicates. Each replicate was a pen with 20 birds. The broiler chickens were fed a control diet with negligible levels of DON (0.19-0.25 mg/kg) or diets naturally contaminated with moderate levels of DON (2.60-2.91 mg/kg), either supplemented or not with an algoclay-based decontaminant (2 g/kg diet). Jejunum villus damage was observed on day 28, followed by villus shortening on d37 in broiler chickens fed the DON-contaminated diet. This negative effect was not observed when the DON-contaminated diet was supplemented with the algoclay-based decontaminant. On d37, the mRNA expression of glutathione synthetase was significantly increased in the liver of broiler chickens fed the DON-contaminated diet. However, its expression was similar to the control when the birds were fed the DON-contaminated diet supplemented with the algoclay-based decontaminant. In conclusion, the algoclay-based decontaminant reduced the systemic exposure of broiler chickens to DON, OTA, and AFB1 in a single oral bolus model. This can be attributed to the binding of the mycotoxins in the gastrointestinal tract. Moreover, dietary contamination with DON at levels between 2.69 and 2.91 mg/kg did not impair production performance but had a negative impact on broiler chicken intestinal morphology and the liver redox system. When the algoclay-based decontaminant was added to the diet, the harm caused by DON was no longer observed. This correlates with the results obtained in the toxicokinetic assay and can be attributed to a decreased absorption of DON.