Suppression of insulin-like growth factor acid-labile subunit expression--a novel mechanism for deoxynivalenol-induced growth retardation

Protective effects of bone marrow mesenchymal stem cell-derived exosomes loaded cerium dioxide nanoparticle against deoxynivalenol-induced liver damage

BACKGROUND

Deoxynivalenol (DON), a mycotoxin produced by Fusarium species, posed significant threats to food safety and human health due to its widespread prevalence and detrimental effects. Upon exposure, the liver, which played a crucial role in detoxifying DON, experienced depleted antioxidant levels and heightened inflammatory responses. Bone marrow mesenchymal stem cell (BMSC)-derived exosomes (BMSC-exos) exhibited therapeutic potential by promoting cellular repair and delivering bioactive substances, such as cerium dioxide nanoparticles (CeO₂ NPs), which are recognized for their ability to mitigate oxidative stress and inflammation.

RESULTS

We successfully loaded BMSC-exos with CeO2 NPs (BMSC-exos @ CeO2) using extrusion techniques, verified through electron microscopy and elemental mapping. The resulting BMSC-exos @ CeO2 displayed low cytotoxicity, boosted antioxidant activity, and reduced inflammation in Hepa 1-6 cells with DON condition. In vivo study, BMSC-exos @ CeO2 maintained stability for 72 h, it also can prevent antioxidant depletion and inhibit liver inflammation under the DON condition. After BMSC-exos @ CeO2 treatment, multi-omics analyses further highlighted significant changes in metabolic and protein signaling pathways, notably in linoleic and arachidonic acid metabolism. Key pathways about AMPK and JAK1/STAT3 were involved in mitigating liver damage with or without DON.

CONCLUSION

Our findings revealed BMSC-exos @ CeO2 as a promising therapeutic strategy against DON's toxicity, offering valuable insights into their potential for liver protection.

CYP2E1 mediated deoxynivalenol-induced hepatocyte toxicity by regulating ferroptosis

Deoxynivalenol (DON), one of the most common mycotoxins in food and feed, can cause acute and chronic liver injury, posing a serious health risk to humans and animals. One of the important manifestations of DON-induced hepatotoxicity is ferroptosis. It has been reported that CYP2E1 can mediated ferroptosis, but the role of DON-induced CYP2E1 in DON-induced ferroptosis in hepatocytes is unknown. In the present study, we observed that DON significantly increased the expression of CYP2E1 and decreased the expression of the ferroptosis inhibitory proteins GPX4 and SLC7A11, as well as GCLC and NQO1. This resulted in an increase in the levels of cell lipid ROS and FeII, 4-HNE, which ultimately led to cell ferroptosis. Notably, knockdown of CYP2E1 resulted in an increase in DON-induced low levels of GPX4 and SLC7A11, a decrease in DON-induced high levels of lipid ROS, FeII and cell secreted 4-HNE, thus ameliorating cell ferroptosis. Moreover, the ferroptosis inhibitor ferrostatin-1 was observed to antagonise the cell growth inhibitory toxicity induced by DON exposure. This was achieved by blocking the increase in lipid ROS and FeII overload, which in turn reduced the extent of ferroptosis and increased IGF-1 protein expression. In conclusion, the present study demonstrated that CYP2E1 played a regulatory role in DON-induced ferroptosis in hepatocytes. Targeting ferroptosis may prove an effective strategy for alleviating DON-induced cell growth retardation toxicity. These findings provided a potential target and strategies to mitigate DON hepatotoxicity in the future.

Transcriptome analysis of adipose tissue and muscle of Laiwu and Duroc pigs

Fat content is an important trait in pig production. Adipose tissue and muscle are important sites for fat deposition and affect production efficiency and quality. To regulate the fat content in these tissues, we need to understand the mechanisms behind fat deposition. Laiwu pigs, a Chinese indigenous breed, have significantly higher fat content in both adipose tissue and muscle than commercial breeds such as Duroc. In this study, we analyzed the transcriptomes in adipose tissue and muscle of 21-d-old Laiwu and Duroc piglets. Results showed that there were 828 and 671 differentially expressed genes (DEG) in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT), respectively. Functional enrichment analysis showed that these DEG were enriched in metabolic pathways, especially carbohydrate and lipid metabolism. Additionally, in the longissimus muscle (LM) and psoas muscle (PM), 312 and 335 DEG were identified, demonstrating enrichment in the cell cycle and metabolic pathways. The protein-protein interaction (PPI) networks of these DEG were analyzed and potential hub genes were identified, such as FBP1 and SCD in adipose tissues and RRM2 and GADL1 in muscles. Meanwhile, results showed that there were common DEG between adipose tissue and muscle, such as LDHB, THRSP, and DGAT2. These findings showed that there are significant differences in the transcriptomes of the adipose tissue and muscle between Laiwu and Duroc piglets (P < 0.05), especially in metabolic patterns. This insight serves to advance our comprehensive understanding of metabolic regulation in these tissues and provide targets for fat content regulation.

A comprehensive review of mycotoxins: Toxicology, detection, and effective mitigation approaches

Mycotoxins, harmful compounds produced by fungal pathogens, pose a severe threat to food safety and consumer health. Some commonly produced mycotoxins such as aflatoxins, ochratoxin A, fumonisins, trichothecenes, zearalenone, and patulin have serious health implications in humans and animals. Mycotoxin contamination is particularly concerning in regions heavily reliant on staple foods like grains, cereals, and nuts. Preventing mycotoxin contamination is crucial for a sustainable food supply. Chromatographic methods like thin layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), and liquid chromatography coupled with a mass spectrometer (LC/MS), are commonly used to detect mycotoxins; however, there is a need for on-site, rapid, and cost-effective detection methods. Currently, enzyme-linked immunosorbent assays (ELISA), lateral flow assays (LFAs), and biosensors are becoming popular analytical tools for rapid detection. Meanwhile, preventing mycotoxin contamination is crucial for food safety and a sustainable food supply. Physical, chemical, and biological approaches have been used to inhibit fungal growth and mycotoxin production. However, new strains resistant to conventional methods have led to the exploration of novel strategies like cold atmospheric plasma (CAP) technology, polyphenols and flavonoids, magnetic materials and nanoparticles, and natural essential oils (NEOs). This paper reviews recent scientific research on mycotoxin toxicity, explores advancements in detecting mycotoxins in various foods, and evaluates the effectiveness of innovative mitigation strategies for controlling and detoxifying mycotoxins.

Innovative approaches for mycotoxin detection in various food categories

Mycotoxins (MTs), produced by filamentous fungi, represent a severe hazard to the health of humans and food safety, affecting the quality of various agricultural products. They can contaminate a wide range of foods, during any processing phase before or after harvest. Animals and humans who consume MTs-contaminated food or feed may experience acute or chronic poisoning, which may result in serious pathological consequences. Accordingly, developing rapid, easy, and accurate methods of MTs detection in food becomes highly urgent and critical as a quality control and to guarantee food safety and lower health hazards. In this review, we highlighted and discussed innovative approaches like biosensors, fluorescent polarization, capillary electrophoresis, infrared spectroscopy, and electronic noses for MT identification pointing out current challenges and future directions. The limitations, current challenges, and future directions of conventional detection methods versus innovative methods have also been highlighted and discussed.

Adverse associations between maternal deoxynivalenol exposure and birth outcomes: a prospective cohort study in China

BACKGROUND

Deoxynivalenol (DON), one of the most prevalent mycotoxins, has been found to cause fetal growth retardation in animals. However, limited evidence exists regarding its effects on pregnant women.

METHODS

Maternal urinary concentration of total DON (tDON) and free DON (fDON) in the second trimester was measured using liquid chromatography with tandem mass spectrometry. Provisional daily intake (PDI) of DON was calculated based on tDON concentration. Linear and logistic regression models were used to evaluate the association between DON exposure levels and birth weight, birth length, and the risk of small for gestational age (SGA).

RESULTS

Among 1538 subjects, the median concentrations of tDON and fDON were 12.1 ng/mL and 5.1 ng/mL, respectively. The PDI values revealed that the median DON intake was 0.7 µg/kg bw, and 35.9% of the total population exceeded the provisional maximum tolerable daily intake (PMTDI) of 1 µg/kg bw. Compared with the lowest tertile, birth weight decreased by 81.11 g (95% CI: -127.00, -35.23) for tDON (P-trend < 0.001) and 63.02 g (95% CI: -108.72, -17.32) for fDON (P-trend = 0.004) in the highest tertile. Each unit increase in Ln-tDON and Ln-fDON was also inversely associated with birth weight. Furthermore, compared to those who did not exceed PMTDI, pregnant women whose PDI exceeded PMTDI had lower birth weight (β = -79.79 g; 95% CI: -119.09, -40.49) and birth length (β = -0.21 cm; 95% CI: -0.34, -0.07), and a higher risk of SGA (OR = 1.48; 95% CI: 1.02, 2.15) in their offspring. Similar associations with birth weight, birth length, and SGA were found when comparing the highest tertile of PDI to the lowest tertile (all P-trend < 0.05).

CONCLUSIONS

Maternal DON exposure is related to decreased birth weight. Our findings implicate that DON exposure during pregnancy may cause fetal growth faltering, and measures should be taken to reduce DON exposure in pregnant women.

Deoxynivalenol: Emerging Toxic Mechanisms and Control Strategies, Current and Future Perspectives

Deoxynivalenol (DON) is the most frequently present mycotoxin contaminant in food and feed, causing a variety of toxic effects in humans and animals. Currently, a series of mechanisms involved in DON toxicity have been identified. In addition to the activation of oxidative stress and the MAPK signaling pathway, DON can activate hypoxia-inducible factor-1α, which further regulates reactive oxygen species production and cancer cell apoptosis. Noncoding RNA and signaling pathways including Wnt/β-catenin, FOXO, and TLR4/NF-κB also participate in DON toxicity. The intestinal microbiota and the brain-gut axis play a crucial role in DON-induced growth inhibition. In view of the synergistic toxic effect of DON and other mycotoxins, strategies to detect DON and control it biologically and the development of enzymes for the biodegradation of various mycotoxins and their introduction in the market are the current and future research hotspots.

Mycotoxins were not associated with environmental enteropathy in a cohort of Tanzanian children

Enteropathy is a pathophysiological condition characterized by decreased intestinal barrier function and absorption. Past studies have hypothesized that mycotoxins might impair children's growth by causing intestinal enteropathy, including interactions between mycotoxins and pathogens. We investigated the association of two mycotoxins, aflatoxin B1 (AFB1 ) and fumonisin B1 (FB1 ), independently and in conjunction with microbial pathogens, with fecal biomarkers of environmental enteropathy in children. As part of a larger MAL-ED study, 196 children were recruited in Haydom, Tanzania, and followed for the first 36 months of life. The gut inflammation biomarkers myeloperoxidase (MPO), neopterin (NEO), and alpha-1-antitrypsin (A1AT) were analyzed in stool samples at 24 months; with mean concentrations 5332.5 ng/L MPO, 807.2 nmol/L NEO, and 0.18 mg/g A1AT. Forty-eight children were measured for AFB1 -lys, with a mean of 5.30 (95% CI: 3.93-6.66) pg/mg albumin; and 87 were measured for FB1 , with a mean of 1.25 (95% CI: 0.72-1.76) ng/ml urine. Although the pathogens adenovirus and Campylobacter were associated with A1AT (p = 0.049) and NEO (p = 0.004), respectively, no association was observed between aflatoxin (MPO, p = 0.30; NEO, p = 0.08; A1AT, p = 0.24) or fumonisin (MPO, p = 0.38; NEO, p = 0.65; A1AT, p = 0.20) exposure and any gut inflammation biomarkers; nor were interactive effects found between mycotoxins and pathogens in contributing to intestinal enteropathy in this cohort. Although further studies are needed to confirm these results, it is possible that mycotoxins contribute to child growth impairment via mechanisms other than disrupting children's intestinal function.

Novel potential biomarkers for severe alcoholic liver disease

Background

Alcoholic liver disease (ALD) is a leading cause of advanced liver disease; however, minor clinical symptoms in the early stage frequently result in delayed diagnosis and therapy. Invasive liver biopsy, the gold standard for diagnosing ALD, is unsuitable for repetitive analysis. This study aims to identify potential serum biomarkers that could contribute to non-invasive disease screening and monitoring.

Methods

Label-free LC-MS/MS quantitative proteomics analysis was performed to identify differentially expressed proteins in the discovery cohort, followed by bioinformatics analysis based on the KEGG, GO, and String databases. Prioritized proteins were validated subsequently by quantitative assays. The area under the receiver operating characteristic curve (AUROC) was used to assess the diagnosis performance of potential biomarkers.

Results

A total of 161 differentially expressed proteins were identified in the discovery cohort, of which 123 were up-regulated and 38 were down-regulated. B2M, IGFALS, and IGFBP3 were evaluated, and all demonstrated excellent diagnosis performance with AUROCs of over 0.9 when distinguishing patients with severe ALD from healthy controls. The AUROC values of B2M, IGFBP3, and IGFALS were 0.7131, 0.8877, and 0.9896 for differentiating severe ALD from non-severe ALD to indicate disease severity. B2M could distinguish patients with non-severe ALD and HC participants with an AUROC value of 0.8985. The efficiency of multiple combinations of these biomarkers was superior to that of the existing liver fibrosis evaluation indices used to monitor disease progression, with AUROC values of over 0.9. IGFALS showed a positive correlation with ALT/AST (r=0.4648, P=0.0009) and may be developed as a therapeutic target.

Conclusion

This proteomic study identified three novel candidate proteins as promising circulating biomarkers for clinical diagnosis and disease progression and also provided the proteomic atlas for ALD pathophysiological mechanisms.

Effects of Chronic Exposure to Diets Containing Moldy Corn or Moldy Wheat Bran on Growth Performance, Ovarian Follicular Pool, and Oxidative Status of Gilts

Background: We investigated the effect of replacing normal corn (NC) or normal wheat bran (NW) with moldy corn (MC) or moldy wheat bran (MW) on growth, ovarian follicular reserves, and oxidative status. Methods: Sixty-three Landrace × Yorkshire gilts were assigned to seven diets formulated by using MC to replace 0% (control), 25% (25% MC), 50% (50% MC), 75% (75% MC), and 100% NC (100% MC), MW to replace 100% NW (100% MW), and MC and MW to replace 100% NC and 100% NW (100% MC + MW), from postnatal day 110 to day 19 of the second estrous cycle. Results: Feeding the gilts with MC or MW induced a lower average daily gain at days 29−56 of the experiment. Age at puberty remained unchanged, but MC inclusion resulted in a linear decrease in antral follicles with diameter >3.0 mm, and control gilts had a 12.7 more large antral follicles than gilts in the 100% MC + MW treatment. MC inclusion linearly decreased the numbers of primordial follicles, growing follicles, and corpora lutea, associated with a lower anti-Müllerian hormone level in serum and 17β-estradiol level in follicular fluid. MC inclusion decreased the serum concentrations of insulin-like growth factor 1 and its mRNA levels in the liver, combined with higher malondialdehyde concentration and lower total superoxide dismutase activities in serum and liver. Conclusion: Chronic exposure to MC-containing diets caused the loss of follicles, even if levels of deoxynivalenol, zearalenone, and aflatoxin B1 were below the levels allowed by China and Europe standards.

Cytochrome P450 enzymes mediated by DNA methylation is involved in deoxynivalenol-induced hepatoxicity in piglets

Deoxynivalenol (DON) is an inevitable contaminant in animal feed and can lead to liver damage, then decreasing appetite and causing growth retardation in piglets. Although many molecular mechanisms are related to hepatoxicity caused by DON, few studies have been done on cytochrome P450 (CYP450) enzymes and DNA methylation. To explore the role of CYP450 enzymes and DNA methylation in DON-induced liver injury, male piglets were fed a control diet, or diet containing 1.0 or 3.0 mg/kg DON for 4 weeks. DON significantly raised the activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutamyl transpeptidase (GGT) (P < 0.01), leading to liver injury. In vivo study found that DON exposure increased the expression of CYP450 enzymes (such as CYP1A1, CYP2E1, CYP3A29) (P < 0.05), and disturbed the expression of nicotinamide N-methyltransferase (NNMT), galanin-like peptide (GALP) and insulin-like growth factor 1 (IGF-1) (P < 0.05), in which DNA methylation affected the expression of these genes. In vitro study (human normal hepatocytes L02) further proved that DON elevated the expression of CYP1A1, CYP2E1 and CYP3A4 (P < 0.05), and inhibited cell growth in a dose-dependent manner, resulting in cell necrosis. More importantly, knockdown of CYP1A1 or CYP2E1 could alleviate DON-induced growth inhibition by promoting IGF-1 expression. Taken together, increased CYP450 enzymes expression was one of the mechanisms of hepatoxicity and growth inhibition induced by DON, suggesting that the decrease of CYP450 enzymes can antagonize the hepatoxicity in animals, which provides some value for animal feed safety.

Mycotoxins in food and feed: toxicity, preventive challenges, and advanced detection techniques for associated diseases

Mycotoxins are produced primarily as secondary fungal metabolites. Mycotoxins are toxic in nature and naturally produced by various species of fungi, which usually contaminate food and feed ingredients. The growth of these harmful fungi depends on several environmental factors, such as pH, humidity, and temperature; therefore, the mycotoxin distribution also varies among global geographical areas. Various rules and regulations regarding mycotoxins are imposed by the government bodies of each country, which are responsible for addressing global food and health security concerns. Despite this legislation, the incidence of mycotoxin contamination is continuously increasing. In this review, we discuss the geographical regulatory guidelines and recommendations that are implemented around the world to control mycotoxin contamination of food and feed products. Researchers and inventors from various parts of the world have reported several innovations for controlling mycotoxin-associated health consequences. Unfortunately, most of these techniques are restricted to laboratory scales and cannot reach users. Consequently, to date, no single device has been commercialized that can detect all mycotoxins that are naturally available in the environment. Therefore, in this study, we describe severe health hazards that are associated with mycotoxin exposure, their molecular signaling pathways and processes of toxicity, and their genotoxic and cytotoxic effects toward humans and animals. We also discuss recent developments in the construction of a sensitive and specific device that effectively implements mycotoxin identification and detection methods. In addition, our study comprehensively examines the recent advancements in the field for mitigating the health consequences and links them with the molecular and signaling pathways that are activated upon mycotoxin exposure.

Toxic mechanisms of the trichothecenes T-2 toxin and deoxynivalenol on protein synthesis

The toxic mechanisms of trichothecenes, including T-2 toxin and deoxynivalenol (DON), are closely related with their effects on protein synthesis. Increasing lines of evidence show that T-2 toxin can reduce the levels of tight junction proteins, and nuclear factor erythroid 2-related factor 2 (Nrf2) by disrupting cellular barriers and the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) and Nrf2/heme oxygenase (HO)-1 pathways. Moreover, it can inhibit aggrecan synthesis, thus causing Kashin-Beck disease. Regarding type B trichothecene, DON inhibits activation marker and β-catenin synthesis by acting on immune cells and the wingless/integrated (Wnt) pathway; it also inhibits cell proliferation and immune surveillance. In addition, DON has been shown to destroy tight junctions, glucose transport, and tumor endothelial marker 8, thus disturbing intestinal function and changing cell migration. This review summarizes the inhibitory effects of the trichothecenes T-2 toxin and DON on different protein synthesis, while discussing their underlying mechanisms. Focus is given to the effects of these toxins on tight junctions, aggrecan, activation markers, and hormones including testosterone under the influence of steroidogenic enzymes. This review can extend the current understanding of the effects of trichothecenes on protein synthesis and help to further understand their toxic mechanisms.

Mycotoxins’ Toxicological Mechanisms Involving Humans, Livestock and Their Associated Health Concerns: A Review

Mycotoxins are well established toxic metabolic entities produced when fungi invade agricultural/farm produce, and this happens especially when the conditions are favourable. Exposure to mycotoxins can directly take place via the consumption of infected foods and feeds; humans can also be indirectly exposed from consuming animals fed with infected feeds. Among the hundreds of mycotoxins known to humans, around a handful have drawn the most concern because of their occurrence in food and severe effects on human health. The increasing public health importance of mycotoxins across human and livestock environments mandates the continued review of the relevant literature, especially with regard to understanding their toxicological mechanisms. In particular, our analysis of recently conducted reviews showed that the toxicological mechanisms of mycotoxins deserve additional attention to help provide enhanced understanding regarding this subject matter. For this reason, this current work reviewed the mycotoxins’ toxicological mechanisms involving humans, livestock, and their associated health concerns. In particular, we have deepened our understanding about how the mycotoxins’ toxicological mechanisms impact on the human cellular genome. Along with the significance of mycotoxin toxicities and their toxicological mechanisms, there are associated health concerns arising from exposures to these toxins, including DNA damage, kidney damage, DNA/RNA mutations, growth impairment in children, gene modifications, and immune impairment. More needs to be done to enhance the understanding regards the mechanisms underscoring the environmental implications of mycotoxins, which can be actualized via risk assessment studies into the conditions/factors facilitating mycotoxins’ toxicities.

An Automatic Immunoaffinity Pretreatment of Deoxynivalenol Coupled with UPLC-UV Analysis

An immunoaffinity magnetic beads (IMBs) based automatic pretreatment method was developed for the quantitative analysis of deoxynivalenol (DON) by ultra-performance liquid chromatography and ultraviolet detector (UPLC-UV). First, N-hydroxysuccinimide-terminated magnetic beads (NHS-MBs) with good magnetic responsivity and dispersibility were synthesized and characterized by optical microscopy, scanning electron microscopy (SEM), and laser diffraction-based particle size analyzer. Then, the amino groups of anti-DON monoclonal antibody (mAb) and the NHS groups of NHS-MBs were linked by covalent bonds to prepare IMB, without any activation reagent. The essential factors affecting the binding and elution of DON were meticulously tuned. Under optimal conditions, DON could be extracted from a real sample and eluted from IMB by water, enabling environmentally friendly and green analysis. Hence, there was no need for dilution or evaporation prior to UPLC-UV analysis. DON in 20 samples could be purified and concentrated within 30 min by the mycotoxin automated purification instrument (MAPI), allowing for automated, green, high-throughput and simple clean-up. Recoveries at four distinct spiking levels in corn and wheat ranged from 92.0% to 109.5% with good relative standard deviations (RSD, 2.1-7.0%). Comparing the test results of IAC and IMB in commercial samples demonstrated the reliability and superiority of IMB for quantitatively analyzing massive samples.

Recent Progress in Rapid Determination of Mycotoxins Based on Emerging Biorecognition Molecules: A Review

Mycotoxins are secondary metabolites produced by fungal species, which pose significant risk to humans and livestock. The mycotoxins which are produced from Aspergillus, Penicillium, and Fusarium are considered most important and therefore regulated in food- and feedstuffs. Analyses are predominantly performed by official laboratory methods in centralized labs by expert technicians. There is an urgent demand for new low-cost, easy-to-use, and portable analytical devices for rapid on-site determination. Most significant advances were realized in the field bioanalytical techniques based on molecular recognition. This review aims to discuss recent progress in the generation of native biomolecules and new bioinspired materials towards mycotoxins for the development of reliable bioreceptor-based analytical methods. After brief presentation of basic knowledge regarding characteristics of most important mycotoxins, the generation, benefits, and limitations of present and emerging biorecognition molecules, such as polyclonal (pAb), monoclonal (mAb), recombinant antibodies (rAb), aptamers, short peptides, and molecularly imprinted polymers (MIPs), are discussed. Hereinafter, the use of binders in different areas of application, including sample preparation, microplate- and tube-based assays, lateral flow devices, and biosensors, is highlighted. Special focus, on a global scale, is placed on commercial availability of single receptor molecules, test-kits, and biosensor platforms using multiplexed bead-based suspension assays and planar biochip arrays. Future outlook is given with special emphasis on new challenges, such as increasing use of rAb based on synthetic and naïve antibody libraries to renounce animal immunization, multiple-analyte test-kits and high-throughput multiplexing, and determination of masked mycotoxins, including stereoisomeric degradation products.

Mycotoxin deoxynivalenol affects myoblast differentiation via downregulating cytoskeleton and ECM-integrin-FAK-RAC-PAK signaling pathway

As a common mycotoxin, deoxynivalenol (DON) contaminates cereal grains and feed in field or during processing and storage. DON elicits a spectrum of adverse effects in animals including anorexia and growth retardation. Especially, the presence of DON has also been detected in muscle, suggesting that DON may has the potential to affect the development of muscle. However, the relevant research is very rare and the molecular mechanism remains unclear. Myoblasts differentiation into multinucleated myotubes is one of the crucial steps of skeletal muscle development. In the present study, we investigated the effects of DON on differentiation of myoblasts using murine C2C12 cells model. The results indicated that DON dose-dependent inhibited the formation of myotubes in C2C12 cells. After performing omics techniques, a total of 149 differentially expressed genes were identified. The expression of cytoskeleton proteins and extracellular matrix (ECM) proteins were downregulated by DON. Furthermore, DON significantly downregulated the expression of integrin αv and integrin β5, leading to inhibition of the ECM-integrin receptor interaction. The focal adhesion kinase (FAK) and phosphorylated forms, ras-related C3 botulinum toxin substrate (RAC) and p21-activated kinases 1 (PAK1) were also downregulated by DON. Taken together, our findings suggest that DON has the potent to affect the differentiation of myoblasts via downregulating of cytoskeleton and ECM-integrin-FAK-RAC-PAK signaling pathway.

Baicalin-Zinc Complex Alleviates Inflammatory Responses and Hormone Profiles by Microbiome in Deoxynivalenol Induced Piglets

This study aimed to investigate the beneficial effect of baicalin–zinc complex (BZN) on intestinal microorganisms in deoxynivalenol (DON)-challenged piglets and the association between intestinal microorganisms and host immunity and hormone secretion. Forty weaned piglets were randomly divided into four treatments with 10 piglets in each treatment: (1) control (Con) group (pigs fed basal diet); (2) DON group (pigs fed 4 mg DON/kg basal diet); (3) BZN group (pigs fed 0.5% BZN basal diet); and (4) DBZN group (pigs fed 4 mg DON/kg and 0.5% BZN basal diet). The experiment lasted for 14 days. The BZN supplementation in DON-contaminated diets changed the intestinal microbiota composition and increased intestinal microbial richness and diversity of piglets. The BZN supplementation in DON-contaminated diets also alleviated the inflammatory responses of piglets and modulated the secretion of hormones related to the growth axis. Moreover, microbiota composition was associated with inflammatory and hormone secretion. In conclusion, BZN alleviated inflammatory response and hormone secretion in piglets, which is associated with the intestinal microbiome.

Oral deoxynivalenol toxicity in Harlan Sprague Dawley (Hsd:Sprague Dawley® SD®) rat dams and their offspring

There is widespread human exposure to deoxynivalenol (DON), a fungal mycotoxin found globally in many grain-based foods and animal feed. Acute exposures to high levels of DON are associated with gastrointestinal effects and emesis in humans and some animals, but the effects of low-dose exposures throughout the lifetime, a more likely exposure scenario in humans, are understudied. Therefore, this study was designed to identify doses of DON that could be used to evaluate long-term toxicity following perinatal exposure. Time-mated Harlan Sprague Dawley (Hsd:Sprague Dawley® SD®) rats were administered 0, 0.03, 0.1, 0.3, 1, or 3 mg/kg/day of DON once daily via gavage starting on gestational day 6 through postnatal day (PND) 27. F1 animals were administered the same dose as their respective dams via gavage starting on PND 12 until PND 27. Animals were euthanized on PND 28. DON had no effect on maternal body weight or feed consumption at any dose. Findings were limited to the 3 mg/kg/day group: F0 females had smaller live litter sizes than controls and F1 pups had lower body weight (4-13%) compared to controls. By PND 28, F1 body weight, after adjustments for litter effects, was 10-13% lower than controls. Blood samples obtained on PND 28 showed no increases in frequencies of micronucleated immature erythrocytes in either F0 or F1 animals. In summary, doses of DON up to 3 mg/kg/day did not affect maternal survival or body weight. Doses of 3 mg/kg/day resulted in slight toxicity manifested as decreased body weight in the offspring. The no-observed effect level was 1 mg/kg/day.

Baicalin-Copper Complex Modulates Gut Microbiota, Inflammatory Responses, and Hormone Secretion in DON-Challenged Piglets

Simple Summary

Deoxynivalenol (DON) is the most common mycotoxin contaminant in the agriculture industry worldwide. Copper is very efficacious in promoting growth performance and improving feed remuneration, and baicalin may alleviate oxidative stress and inflammatory responses in humans and animals. We speculated that the combined effect of baicalin and copper would have some effect in DON-challenged piglets. The present study examined the effects of a baicalin-copper complex on inflammatory responses, hormone secretion, and gut microbiota in DON challenged piglets. These findings provide new application prospects in piglets involving the combination of baicalin and copper.

Abstract

The present experiment assessed the inflammatory responses, hormone secretion, and gut microbiota of weanling piglets administered baicalin-copper complex (BCU) or deoxynivalenol (DON) supplementation diets. Twenty-eight piglets were randomly assigned to four groups: control diet (Con group), a 4 mg DON/kg diet (DON group), a 5 g BCU/kg diet (BCU group), a 5 g BCU + 4 mg DON/kg diet (DBCU group). After 14 days, the results showed that dietary BCU supplementation remarkably increased the relative abundance of Clostrium bornimense and decreased the relative abundance of Lactobacillus in the DBCU group (p < 0.05). BCU decreased the serum concentration of IgG, IL-2, IFN-γ, and IgA in DON treated piglets (p < 0.05), and promoted the serum concentration of IL-1β, IgG, IL-2, IFN-γ, IgA, IL-6, IgM, and TNFα in normal piglets (p < 0.05). BCU increased the concentrations of serum IGF1, insulin, NPY, GLP-1, and GH, and decreased the concentrations of serum somatostatin in no DON treated piglets (p < 0.05). Dietary BCU supplementation significantly promoted the secretion of somatostatin, and inhibited the secretion of leptin in piglets challenged with DON (p < 0.05). BCU regulated the expression of food intake-related genes in the hypothalamus and pituitary of piglets. Collectively, dietary BCU supplementation alleviated inflammatory responses and regulated the secretion of appetite-regulating hormones and growth-axis hormones in DON challenged piglets, which was closely linked to changes of intestinal microbes.

Deoxynivalenol: toxicological profiles and perspective views for future research

Deoxynivalenol (DON) is a secondary metabolite mainly produced by the fungi Fusarium in agricultural crops, widely existing in feeds and cereal-based foodstuffs. Because of the high occurrence and potentials to induce a variety of toxic effects on animals and humans, DON has been a very harmful exogenous dietary toxicant threating public health. The focus of this review is to summarise the DON-induced broad spectrum of adverse health effects, to probe the current state of knowledge of combined toxicity of DON with other mycotoxins and its derivatives, and to put forward prospective ideas that multi-generational toxicity of DON and its overall impacts on intestinal-immuno-neuroendocrine system could receive more attention in future investigations. The general aim is to provide a scientific basis for the necessity to re-consider risk-assessment and regulations.

T1000: a reduced gene set prioritized for toxicogenomic studies

There is growing interest within regulatory agencies and toxicological research communities to develop, test, and apply new approaches, such as toxicogenomics, to more efficiently evaluate chemical hazards. Given the complexity of analyzing thousands of genes simultaneously, there is a need to identify reduced gene sets. Though several gene sets have been defined for toxicological applications, few of these were purposefully derived using toxicogenomics data. Here, we developed and applied a systematic approach to identify 1,000 genes (called Toxicogenomics-1000 or T1000) highly responsive to chemical exposures. First, a co-expression network of 11,210 genes was built by leveraging microarray data from the Open TG-GATEs program. This network was then re-weighted based on prior knowledge of their biological (KEGG, MSigDB) and toxicological (CTD) relevance. Finally, weighted correlation network analysis was applied to identify 258 gene clusters. T1000 was defined by selecting genes from each cluster that were most associated with outcome measures. For model evaluation, we compared the performance of T1000 to that of other gene sets (L1000, S1500, Genes selected by Limma, and random set) using two external datasets based on the rat model. Additionally, a smaller (T384) and a larger version (T1500) of T1000 were used for dose-response modeling to test the effect of gene set size. Our findings demonstrated that the T1000 gene set is predictive of apical outcomes across a range of conditions (e.g., in vitro and in vivo, dose-response, multiple species, tissues, and chemicals), and generally performs as well, or better than other gene sets available.

Potential Link between Gut Microbiota and Deoxynivalenol-Induced Feed Refusal in Weaned Piglets

This study investigated the potential link between gut microbiota and deoxynivalenol (DON)-induced feed refusal. A total of 24 barrows were randomly divided into one of three diets containing 0.61 (control diet), 1.28, or 2.89 mg DON/kg feed for 28 days. Dietary exposure to DON at 2.89 mg/kg significantly decreased the relative abundances of unclassified_f_Lachnospiraceae, Phascolarctobacterium and Ruminococcaceae_UCG-014, whereas it increased Prevotella_9 and norank_f_Prevotellaceae in the cecal digesta. Moreover, the decreased relative abundance of unclassified_f_Lachnospiraceae induced by DON exposure was positively correlated with average daily feed intake. Exposure to DON increased the serum concentrations of glucagon-like peptide-1 and peptide YY but reduced the levels of serum growth hormone and insulin-like growth factor 1. In summary, these findings suggest that chronic dietary exposure to DON induces disturbances of intestinal microbiota. Disturbed appetite-regulating hormones and somatotropic-axis-hormone secretion induced by negative microbial changes could be the potential mechanisms for DON-induced anorexia.

Deoxynivalenol decreased intestinal immune function related to NF-κB and TOR signalling in juvenile grass carp (Ctenopharyngodon idella)

Deoxynivalenol (DON) is one of the most common mycotoxins in animal feed worldwide and causes significant threats to the animal production. The intestine is an important mucosal immune organ in teleost, and it is also the first target for feed-borne toxicants in animal. However, studies concerning the effect of DON on fish intestine are scarce. This study explored the effects of DON on intestinal immune function in juvenile grass carp (Ctenopharyngodon idella). A total of 1440 juvenile grass carp (12.17 ± 0.01 g) were fed six diets containing graded levels of DON (27, 318, 636, 922, 1243 and 1515 μg/kg diet) for 60 days. After the growth trial, fish were challenged with Aeromonas hydrophila. The results were analysed by the Duncan's multiple-range test (P < 0.05), indicating that compared with the control group (27 μg/kg diet), dietary DON levels up to 318 μg/kg diet: (1) decreased lysozyme (LZ) and acid phosphatase (ACP) activities, as well as complement 3 (C3), C4 and immunoglobulin M (IgM) content in the proximal intestine (PI), middle intestine (MI) and distal intestine (DI) of juvenile grass carp (P < 0.05); (2) down-regulated the mRNA levels of anti-microbial substance: liver expressed antimicrobial peptide (LEAP) -2A, LEAP-2B, hepcidin, β-defensin-1 and mucin2 in the PI, MI and DI of juvenile grass carp (P < 0.05); (3) up-regulated the mRNA levels of pro-inflammatory cytokines [interleukin 1β (IL-1β), tumour necrosis factor α (TNF-α), interferon γ2 (INF-γ2), IL-6 (only in PI), IL-8, IL-12p35, IL-12p40, IL-15 and IL-17D] in the PI, MI and DI of juvenile grass carp (P < 0.05), which might be partly related to nuclear factor kappa B (NF-κB) signalling [IκB kinase β (IKKβ) and IKKγ/inhibitor of κBα (IκBα)/NF-κB (p65 and c-Rel)]; and (4) down-regulated the mRNA levels of anti-inflammatory cytokines [IL-10, IL-11, IL-4/13A (not IL-4/13B), transforming growth factor β1 (TGF-β1) (not TGF-β2)] in the PI, MI and DI of juvenile grass carp (P < 0.05), which might be partly related to target of rapamycin (TOR) signalling [TOR/ribosomal protein S6 kinases 1 (S6K1) and eIF4E-binding proteins (4E-BP)]. All data indicated that DON could impair the intestinal immune function, and its potential regulation mechanisms were partly associated with NF-κB and TOR signalling pathways. Finally, based on the enteritis morbidity, and the LZ and ACP activities as well as IgM content in the PI, the reasonable dose of DON for grass carp were estimated to be 251.66, 305.83, 252.34 and 309.94 μg/kg diet, respectively.

Pyrrolidine Dithiocarbamate (PDTC) Inhibits DON-Induced Mitochondrial Dysfunction and Apoptosis via the NF-κB/iNOS Pathway

Oxidative stress is closely linked to the toxic responses of various cell types in normal and pathophysiological conditions. Deoxynivalenol (DON), an inducer of stress responses in the ribosome and the endoplasmic reticulum (ER), causes mitochondrial dysfunction and mitochondria-dependent apoptosis through oxidative stress in humans and animals. The NF-κB pathway, which is closely linked to oxidative stress, is hypothesized to be a critical signaling pathway for DON-induced toxicity and is a potential target for intervention. The present study was conducted to explore the protective effects of pyrrolidine dithiocarbamate (PDTC) from the toxic effects of DON in rat anterior pituitary GH3 cells. Our results showed that DON activated the NF-κB transcription factors and induced cellular oxidative stress, mitochondrial dysfunction, and apoptosis. Morphological studies using transmission electron microscopy (TEM) and cell apoptosis analyses suggested that PDTC prevented DON-induced mitochondrial dysfunction and apoptosis, probably by preventing the DON-induced translocation of NF-κB p65 into the nucleus, and by inhibiting DON-induced iNOS expression. This led to the blocking of the NF-κB pathway and inhibition of iNOS activity.

Review article: Role of satiety hormones in anorexia induction by Trichothecene mycotoxins

The trichothecenes, produced by Fusarium, contaminate animal feed and human food in all stages of production and lead to a large spectrum of adverse effects for animal and human health. An hallmark of trichothecenes toxicity is the onset of emesis followed by anorexia and food intake reduction in different animal species (mink, mice and pig). The modulation of emesis and anorexia can result from a direct action of trichothecenes in the brain or from an indirect action in the gastrointestinal tract. The direct action of trichothecenes involved specific brain areas such as nucleate tractus solitarius in the brainstem and the arcuate nuclei in the hypothalamus. Activation of these areas in the brain leads to the activation of specific neuronal populations containing anorexigenic factors (POMC and CART). The indirect action of trichothecenes in the gastrointestinal tract involved, by enteroendocrine cells, the secretion of several gut hormones such as cholecystokinin (CCK) and peptide YY (PYY) but also glucagon-like peptide 1 (GLP-1), gastric inhibitory peptide (GIP) and 5-hydroxytryptamine (5-HT), which transmitted signals to the brain via the gut-brain axis. This review summarizes current knowledge on the effects of trichothecenes, especially deoxynivalenol, on emesis and anorexia and discusses the mechanisms underlying trichothecenes-induced food reduction.

Deoxynivalenol decreased the growth performance and impaired intestinal physical barrier in juvenile grass carp (Ctenopharyngodon idella)

Deoxynivalenol (DON) is one of the most common mycotoxin contaminants of animal feed worldwide and brings significant threats to the animal production. However, studies concerning the effect of DON on fish intestine are scarce. This study explored the effects of DON on intestinal physical barrier in juvenile grass carp (Ctenopharyngodon idella). A total of 1440 juvenile grass carp (12.17 ± 0.01 g) were fed six diets containing graded levels of DON (27, 318, 636, 922, 1243 and 1515 μg/kg diet) for 60 days. This study for the first time documented that DON caused body malformation in fish, and histopathological lesions, oxidative damage, declining antioxidant capacity, cell apoptosis and destruction of tight junctions in the intestine of fish. The results indicated that compared with control group (27 μg/kg diet), DON: (1) increased the reactive oxygen species (ROS), malondialdehyde (MDA) and protein carbonyl (PC) content, and up-regulated the mRNA levels of Kelch-like-ECH-associated protein 1 (Keap1: Keap1a but not Keap1b), whereas decreased glutathione (GSH) content and antioxidant enzymes activities, and down-regulated the mRNA levels of antioxidant enzymes (except GSTR in MI) and NF-E2-related factor 2 (Nrf2), as well as the protein levels of Nrf2 in fish intestine. (2) up-regulated cysteinyl aspartic acid-protease (caspase) -3, -7, -8, -9, apoptotic protease activating factor-1 (Apaf-1), Bcl2-associated X protein (Bax), Fas ligand (FasL) and c-Jun N-terminal protein kinase (JNK) mRNA levels, whereas down-regulated B-cell lymphoma-2 (bcl-2) and myeloid cell leukemia-1 (Mcl-1) mRNA levels in fish intestine. (3) down-regulated the mRNA levels of ZO-1, ZO-2b, occludin, claudin-c, -f, -7a, -7b, -11 (except claudin-b and claudin-3c), whereas up-regulated the mRNA levels of claudin-12, -15a (not -15b) and myosin light chain kinase (MLCK) in fish intestine. All above data indicated that DON caused the oxidative damage, apoptosis and the destruction of tight junctions via Nrf2, JNK and MLCK signaling in the intestine of fish, respectively. Finally, based on PWG, FE, PC and MDA, the safe dose of DON for grass carp were all estimated to be 318 μg/kg diet.

Short-term ingestion of deoxynivalenol in naturally contaminated feed alters piglet performance and gut hormone secretion

The mycotoxin deoxynivalenol (DON) generally exists in cereals and affects human and animal health. The aim of this study is to analyze the impacts of DON in naturally contaminated feed on piglet growth performance and intestinal hormone secretion in the short term. We randomly divided 5-week-old piglets into four groups: Control, DON 1,000, DON 2,000 and DON 3,000 groups. Piglets received a feed naturally contaminated with DON (approximately 400, 1,000, 2,000 or 3,000 μg/kg) for 21 days. Body weight showed no significant difference following exposure to DON. The balance of anti-oxidation and oxidation was disrupted by DON after 21 days. The concentration of tumor necrosis factor-alpha (TNF-α) and cyclooxgenase-2 (COX-2) significantly increased (p < .001) in all DON-treated groups. Gut anorexigenic hormone secretion of peptide YY (PYY) and cholecystokinin (CCK) had a time- and dose-dependent relationship with DON exposure; however, there was no effect on orexigenic hormone ghrelin secretion. Changes of histomorphology in the jejunum were observed in DON-treated groups, including villi flattening and fusion, and apical necrosis of villi. These results indicated that DON could suppress piglet growth performance and alter gut hormone secretion in the short term.

Alleviation of mycotoxin biodegradation agent on zearalenone and deoxynivalenol toxicosis in immature gilts

Background

The current study was carried out to evaluate the effects of mycotoxin biodegradation agent (MBA, composed of Bacillus subtilis ANSB01G and Devosia sp. ANSB714) on relieving zearalenone (ZEA) and deoxynivalenol (DON) toxicosis in immature gilts.

Methods

A total of forty pre-pubertal female gilts (61.42 ± 1.18 kg) were randomly allocated to four diet treatments: CO (positive control); MO (negative control, ZEA 596.86 μg/kg feed and DON 796 μg/kg feed); COA (CO + 2 g MBA/kg feed); MOA (MO + 2 g MBA/kg feed). Each treatment contained 10 replicates with 1 gilt per replicate. Gilts were housed in an environmentally controlled room with the partially slatted floor.

Results

During the entire experimental period of 28 d, average daily gain (ADG) and average daily feed intake (ADFI) of gilts in MO group was significantly reduced compared with those in CO group. The vulva size of gilts was significantly higher in MO group than CO group. In addition, significant increases in the plasma levels of IgA, IgG, IL-8, IL-10 and PRL were determined in MO group compared with that in CO group. ZEA and DON in the diet up-regulated apoptotic caspase-3 in ovaries and uteri, along with down-regulated the anti-apoptotic protein Bcl-2 in ovaries. The supplementation of MBA into diets co-contaminated with ZEA and DON significantly increased ADG, decreased the vulva sizes, reduced the levels of IgG, IL-8 and PRL in plasma, and regulated apoptosis in ovaries and uteri of gilts.

Conclusions

The present results indicated that feeding diet contaminated with ZEA and DON simultaneously (596.86 μg/kg + 796 μg/kg) had detrimental effects on growth performance, plasma immune function and reproductive status of gilts. And MBA could reduce the negative impacts of these two toxins, believed as a promising feed additive for mitigating toxicosis of ZEA and DON at low levels in gilts.

Challenge with fumonisins B1 and B2 changes IGF-1 and GHR mRNA expression in liver of Nile tilapia fingerlings

Although fumonisins are identified as responsible for alterations in weight gain, little information is available on their effects on expression of growth-related genes, especially for Nile tilapia (Oreochromis niloticus) fingerlings. In this study, Nile tilapia fingerlings were treated with increasing levels of fumonisin B1 (FB1) and fumonisin B2 (FB2) (diets of 0, 20, 40, and 60 mg/kg) to evaluate their effects on weight gain (WG), feed intake (FI), feed efficiency (FE), growth hormone receptor (GHR) and insulin growth factor 1 (IGF-1) mRNA expression in liver of this fish. All variables were evaluated at 15 and 30 days of treatment. Diet containing 0 mg fumonisin/kg was used as control treatment. Treatment with 20, 40, and 60 mg fumonisin/kg of diet significantly reduced WG (P<0.0001) and FE (P<0.0001), while GHR and IGF-1 mRNA expression was reduced both at 15 and 30 days of treatment. Feed intake was not affected by diets in any of the evaluated periods. These results indicate that fumonisins (FB1 + FB2) affect the growth of Nile tilapia fingerlings through mechanisms that involve reduction of GHR and IGF-1 expression.

Nitric oxide mediates apoptosis and mitochondrial dysfunction and plays a role in growth hormone deficiency by nivalenol in GH3 cells

Nivalenol (NIV), a type B trichothecenes commonly found in cereal crops, can cause growth impairment in animals. However, limited information about its mechanisms is available. Trichothecenes have been characterized as an inhibitor of protein synthesis and induce apoptosis in cells. Oxidative stress is considered an underlying mechanism. However, whether NIV can induce oxidative stress and apoptosis in rat pituitary cells line GH3 is unclear. The present study showed that NIV significantly reduced the viability of cells and caused oxidative stress in GH3 cells. Further experiments showed that nitric oxide (NO), but not ROS, mediated NIV-induced oxidative stress. Additionally, NIV induced caspase-dependent apoptosis, decrease in mitochondrial membrane potential and mitochondrial ultrastructural changes. However, NIV-induced caspase activation, mitochondrial damage and apoptosis were partially alleviated by Z-VAD-FMK or NO scavenger hemoglobin. Finally, NIV changed the expression of growth-associated genes and pro-inflammatory cytokines. NIV also reduced the GH secretion in GH3 cells, which was reversed by hemoglobin. Taken together, these results suggested that NIV induced apoptosis in caspase-dependent mitochondrial pathway in GH3 cells, which might be an underlying mechanism of NIV-induced GH deficiency. Importantly, NO played a critical role in the induction of oxidative stress, apoptosis and GH deficiency in NIV-treated GH3 cells.

Risks to human and animal health related to the presence of deoxynivalenol and its acetylated and modified forms in food and feed

Deoxynivalenol (DON) is a mycotoxin primarily produced by Fusarium fungi, occurring predominantly in cereal grains. Following the request of the European Commission, the CONTAM Panel assessed the risk to animal and human health related to DON, 3-acetyl-DON (3-Ac-DON), 15-acetyl-DON (15-Ac-DON) and DON-3-glucoside in food and feed. A total of 27,537, 13,892, 7,270 and 2,266 analytical data for DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside, respectively, in food, feed and unprocessed grains collected from 2007 to 2014 were used. For human exposure, grains and grain-based products were main sources, whereas in farm and companion animals, cereal grains, cereal by-products and forage maize contributed most. DON is rapidly absorbed, distributed, and excreted. Since 3-Ac-DON and 15-Ac-DON are largely deacetylated and DON-3-glucoside cleaved in the intestines the same toxic effects as DON can be expected. The TDI of 1 μg/kg bw per day, that was established for DON based on reduced body weight gain in mice, was therefore used as a group-TDI for the sum of DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside. In order to assess acute human health risk, epidemiological data from mycotoxicoses were assessed and a group-ARfD of 8 μg/kg bw per eating occasion was calculated. Estimates of acute dietary exposures were below this dose and did not raise a health concern in humans. The estimated mean chronic dietary exposure was above the group-TDI in infants, toddlers and other children, and at high exposure also in adolescents and adults, indicating a potential health concern. Based on estimated mean dietary concentrations in ruminants, poultry, rabbits, dogs and cats, most farmed fish species and horses, adverse effects are not expected. At the high dietary concentrations, there is a potential risk for chronic adverse effects in pigs and fish and for acute adverse effects in cats and farmed mink.

Comparison of Data from a Single-Analyte and a Multianalyte Method for Determination of Urinary Total Deoxynivalenol in Human Samples

Deoxynivalenol (DON) exposure is estimated by the combined measures of urinary DON and DON-glucuronides. In this study, data from single-mycotoxin (SM) and a multimycotoxin (MM) methods were compared for 256 Swedish adult urine samples. Both methods included β-glucuronidase predigestion, immunoaffinity enrichment, and LC-MS/MS. However, the specific reagents, apparatus, and conditions were not identical in part because the MM method measures additional mycotoxins. DON was detected in 88 and 63% of samples using the SM and MM methods, respectively, with the following mean and median concentrations: SM, mean = 5.0 ng/mL, SD = 7.4, range of positives = 0.5-60.2 ng/mL, median = 2.5 ng/mL, IQR = 1.0-5.5 ng/mL; MM, mean = 4.4 ng/mL, SD = 12.9, range of positives = 0.5-135.2 ng/mL, median = 0.8 ng/mL, IQR = 0.3-3.5. Linear regression showed a significant, albeit modest, correlation between the two measures (p = 0.0001, r = 0.591). The differences observed may reflect subtle handling differences in DON extraction and quantitation between the methods.

Mycotoxins: cytotoxicity and biotransformation in animal cells

Mycotoxins are secondary metabolites produced by many microfungi. Hitherto, over 300 mycotoxins with diverse structures have been identified. They contaminate most cereals and feedstuffs, which threaten human and animal health by exerting acute, sub-acute and chronic toxicological effects, with some considered as carcinogens. Many mycotoxins at low concentrations are able to induce the expression of cytochrome P450 and other enzymes implicated in the biotransformation and metabolization of mycotoxins in vivo and in vitro. Mycotoxins and their metabolites elicit different cellular disorders and adverse effects such as oxidative stress, inhibition of translation, DNA damage and apoptosis in host cells, thus causing various kinds of cytotoxicities. In this review, we summarize the biotransformation of mycotoxins in animal cells by CYP450 isoforms and other enzymes, their altered expression under mycotoxin exposure, and recent progress in mycotoxin cytotoxicity in different cell lines. Furthermore, we try to generalize the molecular mechanisms of mycotoxin effects in human and animal cells.

The Potential Role of Mycotoxins as a Contributor to Stunting in the SHINE Trial

Children in developing countries experience multiple exposures that are harmful to their growth and development. An emerging concern is frequent exposure to mycotoxins that contaminate a wide range of staple foods, including maize and groundnuts. Three mycotoxins are suspected to contribute to poor child health and development: aflatoxin, fumonisin, and deoxynivalenol. We summarize the evidence that mycotoxin exposure is associated with stunting, and propose that the causal pathway may be through environmental enteric dysfunction (EED) and disturbance of the insulin-like growth factor 1 (IGF-1) axis. The objectives of this substudy are to assess the relationship between agricultural and harvest practices and mycotoxin exposure; to evaluate associations between mycotoxin exposure and child stunting; and to investigate EED as a potential pathway linking mycotoxin exposure to child stunting, to inform potential areas for intervention.

Integrated Transcriptional and Proteomic Analysis of Growth Hormone Suppression Mediated by Trichothecene T-2 Toxin in Rat GH3 Cells

Chronic exposure to trichothecenes is known to disturb insulin-like growth factor 1 and signaling of insulin and leptin hormones and causes considerable growth retardation in animals. However, limited information was available on mechanisms underlying trichothecene-induced growth retardation. In this study, we employed an integrated transcriptomics, proteomics, and RNA interference (RNAi) approach to study the molecular mechanisms underlying trichothecene cytotoxicity in rat pituitary adenoma GH3 cells. Our results showed that trichothecenes suppressed the synthesis of growth hormone 1 (Gh1) and inhibited the eukaryotic transcription and translation initiation by suppressing aminoacyl-tRNA synthetases transcription, inducing eukaryotic translation initiation factor 2-alpha kinase 2 (EIF2AK2) and reducing eukaryotic translation initiation factor 5 a. The sulfhydryl oxidases , protein disulfide isomerase,and heat shock protein 90 (were greatly reduced, which resulted in adverse regulation of protein processing and folding. Differential genes and proteins associated with a decline in energy metabolism and cell cycle arrest were also found in our study. However, use of RNAi to interfere with hemopoietic cell kinase (Hck) and EIF2AK2 transcriptions or use of chemical inhibitors of MAPK, p38, Ras, and JNK partially reversed the reduction of Gh1 levels induced by trichothecenes. It indicated that the activation of MAPKs, Hck, and EIF2AK2 were important for trichothecene-induced growth hormone suppression. Considering the potential hazards of exposure to trichothecenes, our findings could help to improve our understanding regarding human and animal health implications.

Murine Anorectic Response to Deoxynivalenol (Vomitoxin) Is Sex-Dependent

Deoxynivalenol (DON, vomitoxin), a common trichothecene mycotoxin found in cereal foods, dysregulates immune function and maintenance of energy balance. The purpose of this study was to determine if sex differences are similarly evident in DON's anorectic responses in mice. A bioassay for feed refusal, previously developed by our lab, was used to compare acute i.p. exposures of 1 and 5 mg/kg bw DON in C57BL6 mice. Greater anorectic responses were seen in male than female mice. Male mice had higher organ and plasma concentrations of DON upon acute exposure than their female counterparts. A significant increase in IL-6 plasma levels was also observed in males while cholecystokinin response was higher in females. When effects of sex on food intake and body weight changes were compared after subchronic dietary exposure to 1, 2.5, and 10 ppm DON, males were found again to be more sensitive. Demonstration of male predilection to DON-induced changes in food intake and weight gain might an important consideration in future risk assessment of DON and other trichothecenes.

Growth performance, serum biochemical profile, jejunal morphology, and the expression of nutrients transporter genes in deoxynivalenol (DON)- challenged growing pigs

BACKGROUND

Fusarium infection with concurrent production of deoxynivalenol (DON) causes an increasing safety concern with feed worldwide. This study was conducted to determine the effects of varying levels of DON in diets on growth performance, serum biochemical profile, jejunal morphology, and the differential expression of nutrients transporter genes in growing pigs.

RESULTS

A total of twenty-four 60-day-old healthy growing pigs (initial body weight = 16.3 ± 1.5 kg SE) were individually housed and randomly assigned to receive one of four diets containing 0, 3, 6 or 12 mg DON/kg feed for 21 days. Differences were observed between control and the 12 mg/kg DON treatment group with regards to average daily gain (ADG), although the value for average daily feed intake (ADFI) in the 3 mg/kg DON treatment group was slightly higher than that in control (P<0.01). The relative liver weight in the 12 mg/kg DON treatment group was significantly greater than that in the control (P<0.01), but there were no significant differences in other organs. With regard to serum biochemistry, the values of blood urea nitrogen (BUN), alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate amino transferase (AST) in the 3 treatment groups were higher than those in the control, and the serum concentrations of L-valine, glycine, L-serine, and L-glutamine were significantly reduced in the 3 treatment groups, especially in the 12 mg/kg DON group (P<0.01). Serum total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px) were markedly decreased after exposure to DON contaminated feeds (P<0.01). The villi height was markedly decreased and the lymphocyte cell numbers markedly increased in the 3 DON contaminated feeds (P<0.01). The mRNA expression levels of excitatory amino acid transporter-3 (EAAC-3), sodium-glucose transporter-1 (SGLT-1), dipeptide transporter-1 (PepT-1), cationic amino acid transporter-1 (CAT-1) and y(+)L-type amino acid transporter-1 (LAT-1) in control were slightly or markedly higher than those in the 3 DON treatment groups.

CONCLUSIONS

These results showed that feeds containing DON cause a wide range of effects in a dose-dependent manner. Such effects includes weight loss, live injury and oxidation stress, and malabsorption of nutrients as a result of selective regulation of nutrient transporter genes such as EAAC-3, SGLT-1, PepT-1, CAT-1 and LAT-1.

Deoxynivalenol Impairs Weight Gain and Affects Markers of Gut Health after Low-Dose, Short-Term Exposure of Growing Pigs

Deoxynivalenol (DON) is one of the major mycotoxins produced by Fusarium fungi, and exposure to this mycotoxin requires an assessment of the potential adverse effects, even at low toxin levels. The aim of this study was to investigate the effects of a short-term, low-dose DON exposure on various gut health parameters in pigs. Piglets received a commercial feed or the same feed contaminated with DON (0.9 mg/kg feed) for 10 days, and two hours after a DON bolus (0.28 mg/kg BW), weight gain was determined and samples of different segments of the intestine were collected. Even the selected low dose of DON in the diet negatively affected weight gain and induced histomorphological alterations in the duodenum and jejunum. The mRNA expression of different tight junction (TJ) proteins, especially occludin, of inflammatory markers, like interleukin-1 beta and interleukin-10 and the oxidative stress marker heme-oxigenase1, were affected along the intestine by low levels of DON in the diet. Taken together, our results indicate that even after low-level exposure to DON, which has been generally considered as acceptable in animal feeds, clinically-relevant changes are measurable in markers of gut health and integrity.

Dysregulation of energy balance by trichothecene mycotoxins: Mechanisms and prospects

Trichothecenes are toxic metabolites produced by fungi that constitute a worldwide hazard for agricultural production and both animal and human health. More than 40 countries have introduced regulations or guidelines for food and feed contamination levels of the most prevalent trichothecene, deoxynivalenol (DON), on the basis of its ability to cause growth suppression. With the development of analytical tools, evaluation of food contamination and exposure revealed that a significant proportion of the human population is chronically exposed to DON doses exceeding the provisional maximum tolerable daily dose. Accordingly, a better understanding of trichothecene impact on health is needed. Upon exposure to low or moderate doses, DON and other trichothecenes induce anorexia, vomiting and reduced weight gain. Several recent studies have addressed the mechanisms by which trichothecenes induce these symptoms and revealed a multifaceted action targeting gut, liver and brain and causing dysregulation in neuroendocrine signaling, immune responses, growth hormone axis, and central neurocircuitries involved in energy homeostasis. Newly identified trichothecene toxicosis biomarkers are just beginning to be exploited and already open up new questions on the potential harmful effects of chronic exposure to DON at apparently asymptomatic very low levels. This review summarizes our current understanding of the effects of DON and other trichothecenes on food intake and weight growth.

Aflatoxin exposure is inversely associated with IGF1 and IGFBP3 levels in vitro and in Kenyan schoolchildren

SCOPE

This study explores the relationship between aflatoxin and the insulin-like growth factor (IGF) axis and its potential effect on child growth.

METHODS AND RESULTS

One hundred and ninety-nine Kenyan schoolchildren were studied for aflatoxin-albumin adduct (AF-alb), IGF1 and IGF-binding protein-3 (IGFBP3) levels using ELISA. AF-alb was inversely associated with IGF1 and IGFBP3 (p < 0.05). Both IGF1 and IGFBP3 were significantly associated with child height and weight (p < 0.01). Children in the highest tertile of AF-alb exposure (>198.5 pg/mg) were shorter than children in the lowest tertile (<74.5 pg/mg), after adjusting for confounders (p = 0.043). Path analysis suggested that IGF1 levels explained ∼16% of the impact of aflatoxin exposure on child height (p = 0.052). To further investigate this putative mechanistic pathway, HHL-16 liver cells (where HHL-16 is human hepatocyte line 16 cells) were treated with aflatoxin B1 (0.5, 5 and 20 μg/mL for 24-48 h). IGF1 and IGFBP3 gene expression measured by quantitative PCR and protein in culture media showed a significant down-regulation of IGF genes and reduced IGF protein levels.

CONCLUSION

Aflatoxin treatment resulted in a significant decrease in IGF gene and protein expression in vitro. IGF protein levels were also lower in children with the highest levels of AFB-alb adducts. The data suggest that aflatoxin-induced changes in IGF protein levels could contribute to growth impairment where aflatoxin exposure is high.

Mycotoxin exposure and infant and young child growth in Africa: what do we know?

INTRODUCTION

Infant and young child (IYC) growth impairment remains a public health problem in Africa partly because infants are exposed to staple foods (contaminated with mycotoxins) at an early age. Understanding the role of mycotoxins in IYC growth is vital, and this paper systematically reviews the available knowledge.

METHODS

Studies were searched and included if they provided information on African IYC mycotoxin exposure rates and/or growth. Studies were excluded if subjects were older than 15 years, if they were animal studies or focusing on other mycotoxins. Relevant search words were included in search strings. Eight reviews were identified and reference lists scrutinised for additional studies.

RESULTS

Ten studies were included; 8 focused on aflatoxin (AF), 2 on fumonisin (FB) and none on deoxynivalenol (DON) and zearalenone (ZEA). AF exposure prevalence reached 100% with levels at 40.4 pg/mg. AF was present in umbilical cords indicating that AF crosses the placenta. Maternal exposure levels were correlated with breast milk levels. The highest levels of serum AF (mean 32.8 pg/mg) were measured in Benin and Togo with 5.4% reaching levels higher than 200 pg/mg. At the end of weaning, children had similar prevalence and exposure levels as adults. RESULTS also indicated that infants with higher levels of maternal exposure had significantly lower height-for-age z-scores (HAZ scores), although there was no significant association between cord AF and infant HAZ scores or AF in cord blood and HAZ scores. Significantly higher mean maternal AF levels related to lower weight-for-age z-scores (WAZ scores) were reported, and infants with higher levels of maternal exposure had significantly lower WAZ scores that decreased over age. Cord AF levels had no effect on infant WAZ scores. One study investigated the association between FB and IYC growth and found that those with FB intakes greater than the provisional maximum tolerable daily intake were significantly shorter (1.3 cm) and lighter (328 g). No studies investigated the role of DON and ZEA.

CONCLUSION

A limited number of epidemiological studies have been conducted, and available research indicates extreme exposures to AF. There are strong associations between AF exposure and stunting and wasting. However, more epidemiological research is urgently needed to understand the role of FB, DON and ZEA in IYC growth.

Development and evaluation of a sensitive mycotoxin risk assessment model (MYCORAM)

The differential risk of exposure to fumonisin (FB), deoxynivalenol (DON), and zearalenone (ZEA) mycotoxins to the South African population, residing in the nine Provinces was assessed during a cross-sectional grain consumer survey. The relative per capita maize intake (g/day) was stratified by gender, ethnicity, and Province and the probable daily intake (PDI) for each mycotoxin (ng/kg body weight/day) calculated utilizing SPECIAL and SUPER dry milled maize fractions representing different exposure scenarios. Men consumed on an average more maize (173 g/day) than women (142 g/day) whereas the black African ethnic group had the highest intake (279 g/day) followed by the Colored group (169 g/day) with the Asian/Indian and White groups consuming lower quantities of 101 and 80 g/day, respectively. The estimated mean PDIs for the various subgroups and Provinces, utilizing the different dry milled maize fractions, were below the provisional maximum tolerable daily intake (PMTDI) for each mycotoxin. A distinct and more sensitive mycotoxin risk assessment model (MYCORAM) for exposure, stratified by Province and ethnicity were developed utilizing specific maize intake increments (g/kg body weight/day) that provides information on the percentage of the population exposed above the PMTDI for each mycotoxin. Evaluation of the MYCORAM utilizing commercial and EXPERIMENTALLY DERIVED: SPECIAL milling fractions, containing predefined mycotoxins levels, predicts the percentage of maize consumers exposed above the respective PMTDI. Safety modeling using the MYCORAM could also predict a maximum tolerated level adequate to safeguard all South African maize consumers including the most vulnerable groups.

Influence of temperature and pH on the degradation of deoxynivalenol (DON) in aqueous medium: comparative cytotoxicity of DON and degraded product

Deoxynivalenol (DON), a toxic fungal metabolite, is stable under different processing conditions; however, its stability in aqueous medium at different temperatures and low pH (1-2) (present in the gastrointestinal tract) has not been investigated. In the present study, DON standard was used to study the influence of temperature and pH on DON stability in aqueous medium, the characterisation of the degraded product, and the comparative toxicity profile of the degraded and the parent compound. The results suggest that standard DON was unstable at 125-250°C showing 16-100% degradation whereas DON at pH 1-3 had 30-66% degradation, with a concomitant increase in the formation of a degraded product. Further ESI-MS characterisation of the dominant precursor ion of the HPLC eluate of the DON-degraded product was found to be m/z 279, resembling the known metabolite DOM-1. The degraded product of DON was reconfirmed as DOM-1 by comparison with standard DOM-1 and both gave a similar λmax at 208 nm. Comparative studies of both standard DOM-1 and the degraded product of DON showed no cytotoxicity up to 6400 ng ml(-1) while significant cytotoxicity was observed for DON (400 ng ml(-1)). The results suggest that a highly acidic environment (pH 1-2) could be responsible for the de-epoxydation of DON leading to the formation of DOM-1.

Deoxynivalenol-induced weight loss in the diet-induced obese mouse is reversible and PKR-independent

The trichothecene deoxynivalenol (DON), a potent ribotoxic mycotoxin produced by the cereal blight fungus Fusarium graminearum, commonly contaminates grain-based foods. Oral exposure to DON causes decreased food intake, reduced weight gain and body weight loss in experimental animals - effects that have been linked to dysregulation of hormones responsible for mediating satiety at the central nervous system level. When diet-induced obese (DIO) mice are fed DON, they consume less food, eventually achieving body weights of control diet-fed mice. Here, we extended these findings by characterizing: (1) reversibility of DON-induced body weight loss and anorexia in DIO mice and (2) the role of double-stranded RNA-activated protein kinase (PKR) which has been previously linked to initiation of the ribotoxic stress response. The results demonstrated that DON-induced weight loss was reversible in DIO mice and this effect corresponded to initiation of a robust hyperphagic response. When DIO mice deficient in PKR were exposed to DON, they exhibited weight suppression similar to DIO wild-type fed the toxin, suggesting the toxin's weight effects were not dependent on PKR. Taken together, DON's effects on food consumption and body weight are not permanent and, furthermore, PKR is not an essential signaling molecule for DON's anorectic and weight effects.

From the gut to the brain: journey and pathophysiological effects of the food-associated trichothecene mycotoxin deoxynivalenol

Mycotoxins are fungal secondary metabolites contaminating food and causing toxicity to animals and humans. Among the various mycotoxins found in crops used for food and feed production, the trichothecene toxin deoxynivalenol (DON or vomitoxin) is one of the most prevalent and hazardous. In addition to native toxins, food also contains a large amount of plant and fungal derivatives of DON, including acetyl-DON (3 and 15ADON), glucoside-DON (D3G), and potentially animal derivatives such as glucuronide metabolites (D3 and D15GA) present in animal tissues (e.g., blood, muscle and liver tissue). The present review summarizes previous and very recent experimental data collected in vivo and in vitro regarding the transport, detoxification/metabolism and physiological impact of DON and its derivatives on intestinal, immune, endocrine and neurologic functions during their journey from the gut to the brain.