Effects of maternal T-2 toxin exposure on the hepatic glycolipid metabolism in young mice

A preliminary study of T-2 toxin that cause liver injury in rats via the NF-kB and NLRP3-mediated pyroptosis pathway

T-2 toxin is recognized as the most potent and prevalent secondary metabolite among monotrichous mycotoxins produced by Fusarium species. Multiple studies have substantiated the hepatotoxic effects of T-2 toxin. This study aimed to investigate whether NF-κB and NLRP3-mediated pyroptosis is involved in the underlying mechanism of T-2 toxin hepatotoxicity. We designed three groups of rat models, blank control; solvent control and T-2 toxin (0.2 mg/kg body weight/day), which were euthanized at week 8 after gavage staining of the toxin. Through HE staining and biochemical indicators associated with liver injury, we observed that T-2 toxin induced liver damage in rats. By Western blot analysis and qRT-PCR, we found that the expression levels of pyroptosis-related genes and proteins were significantly higher in the T-2 toxin group. In addition, we also found a significant increase in the expression of p-NF-κB protein, an upstream regulator of NLRP3. In conclusion, NF-κB and NLRP3-mediated pyroptosis may be involved in the mechanism of hepatotoxic action of T-2 toxin, which provides a new perspective.

SIRT5 safeguards against T-2 toxin induced liver injury by repressing iron accumulation, oxidative stress, and the activation of NLRP3 inflammasome

T-2 toxin, a highly toxic trichothecene mycotoxin widely found in food and feed, poses a significant threat to human health as well as livestock and poultry industry. Liver, being a crucial metabolic organ, is particularly susceptible to T-2 toxin induced damage characterized by inflammation and oxidative stress. Despite the role of Sirtuin 5 (SIRT5) in mitigating liver injury has been confirmed, its specific impact on T-2 toxin induced liver injury remains to be elucidated. The objective of this study was to investigate the protective role of SIRT5 against T-2 toxin induced liver injury in mice. Following the oral administration of 1 mg/kg.bw of T-2 toxin for 21 consecutive days to SIRT5 knockout (SIRT5-/-) and wild-type (WT) male mice, liver assessments were conducted. Our findings demonstrated that aggravated hepatic pathological injury was observed in SIRT5-/- mice, accompanied by elevated malondialdehyde (MDA) and Fe levels, as well as enhanced expression of glutathione peroxidase 4 (GPX4), NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, Gasdermin-D (GSDMD), tumour necrosis factor-alpha (TNF-α), and interleukin-1beta (IL-1β). These results indicated that SIRT5 alleviated hepatic structural damage and dysfunction, while inhibiting oxidative stress, iron accumulation, and NLRP3 inflammasome activation. Analysis revealed a positive correlation among NLRP3 inflammasome activation, iron accumulation, and oxidative stress. Overall, our study demonstrated that SIRT5 mitigated liver injury induced by T-2 toxin through inhibiting iron accumulation, oxidative stress, and NLRP3 inflammasome activation, providing novel insights into the management and prevention of T-2 toxin poisoning.

The role of gut microbiota in anorexia induced by T-2 toxin

T-2 toxin is one of trichothecene mycotoxins, which can impair appetite and decrease food intake. However, the specific mechanisms for T-2 toxin-induced anorexia are not fully clarified. Multiple research results had shown that gut microbiota have a significant effect on appetite regulation. Hence, this study purposed to explore the potential interactions of the gut microbiota and appetite regulate factors in anorexia induced by T-2 toxin. The study divided the mice into control group (CG, 0 mg/kg BW T-2 toxin) and T-2 toxin-treated group (TG, 1 mg/kg BW T-2 toxin), which oral gavage for 4 weeks, to construct a subacute T-2 toxin poisoning mouse model. This data proved that T-2 toxin was able to induce an anorexia in mice by increased the contents of gastrointestinal hormones (CCK, GIP, GLP-1 and PYY), neurotransmitters (5-HT and SP), as well as pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) in serum of mice. T-2 toxin disturbed the composition of gut microbiota, especially, Faecalibaculum and Allobaculum, which was positively correlated with CCK, GLP-1, 5-HT, IL-1β, IL-6 and TNF-α, which played a certain role in regulating host appetite. In conclusion, gut microbiota changes (especially an increase in the abundance of Faecalibaculum and Allobaculum) promote the upregulation of gastrointestinal hormones, neurotransmitters, and pro-inflammatory cytokines, which may be a potential mechanism of T-2 toxin-induced anorexia.

T-2 toxin metabolism and its hepatotoxicity: New insights on the molecular mechanism and detoxification

T-2 toxin, a type A trichothecene, is a secondary metabolite produced by Fusarium poae, Fusarium sporotrichioides, and Fusarium tricinctum. As the most toxic trichothecenes, T-2 toxin causes severe damage to multiple organs, especially to liver. However, the contamination of T-2 toxin covers a wide range of plants, including nuts, grains, fruits and herbs globally. And due to chemical stability of T-2 toxin, it is difficult to be completely removed from the food and feeds, which poses a great threat to human and animal health. Liver is the major detoxifying organ which also makes it the main target of T-2 toxin. After being absorbed by intestine, the first pass effect will reduce the level of T-2 toxin in blood indicating that liver is the main metabolic site of T-2 toxin in vivo. In this review, updated researches on the hepatotoxicity of T-2 toxin were summarized. The metabolic characteristic of T-2 toxin in vivo was introduced. The main hepatotoxic mechanisms of T-2 toxin are oxidative stress, mitochondrial damage, deoxyribonucleic acid (DNA) methylation, autophagy and apoptosis. Recent research of the main hepatotoxic mechanisms of T-2 toxin and the interactions between these mechanisms were summarized. The remission of the hepatotoxicity induced by T-2 toxin was also studied in this review followed by new findings on the detoxification of hepatotoxicity induced by T-2 toxin. The review aimed to offer a comprehensive view and proposes new perspectives in the field of hepatotoxicity induced by T-2 toxin.

Dietary T-2 toxin induces transcriptomic changes in hepatopancreas of Chinese mitten crab (Eriocheir sinensis) via nutrition metabolism and apoptosis-related pathways

Long-term feed route exposure to T-2 toxin was proved to elicit growth retarding effects and induction of oxidative stress and apoptosis in Chinese mitten crab (Eriocheir sinensis). However, no study with a holistic perspective has been conducted to date to further describe the in-depth toxicological mechanism of T-2 toxin in E.sinensis. In this study, an RNA-Sequencing (RNA-seq) was used in this study to investigate the effects of feed supplementation with 0 mg/kg and 4 mg/kg T-2 toxin on the hepatopancreas transcriptome of E.sinensis and establish a hepatopancreas transcriptome library of T-2 toxin chronically exposed crabs after five weeks, where 14 differentially expressed genes (DEGs) were screened out across antioxidant, apoptosis, autophagy, glucolipid metabolism and protein synthesis. The actual expression of all the DEGs (Caspase, ATG4, PERK, ACSL, CAT, BIRC2, HADHA, HADHB, ACOX, PFK, eEFe1, eIF4ɑ, RPL13Ae) was also analyzed by real-time quantitative PCR (RT-qPCR). It was demonstrated that long-term intake of large amounts of T-2 toxin could impair antioxidant enzyme activity, promote apoptosis and protective autophagy, disrupt lipid metabolism and inhibit protein synthesis in the hepatopancreas of E.sinensis. In conclusion, this study explored the toxicity mechanism of T-2 toxin on the hepatopancreas of E.sinensis at the mRNA level, which lays the foundation for further investigation of the molecular toxicity mechanism of T-2 toxin in aquatic crustaceans.

Effects of T-2 toxin on growth performance, feather quality, tibia development and blood parameters in Yangzhou goslings

T-2 toxin is a dangerous natural pollutant and widely exists in animal feed, often causing toxic damage to poultry, such as slow growth and development, immunosuppression, and death. Although geese are considered the most sensitive poultry to T-2 toxin, the exact damage caused by T-2 toxin to geese is elusive. In the present study, a total of forty two 1-day-old healthy Yangzhou male goslings were randomly allotted seven diets contaminated with 0, 0.2, 0.4, 0.6, 0.8, 1.0, or 2.0 mg/kg T-2 toxin for 21 d, and the effects of T-2 toxin exposure on growth performance, feather quality, tibia development, and blood parameters were investigated. The results showed that T-2 toxin exposure significantly inhibited feed intake, body weight gain, shank length growth, and organ development (e.g., ileum, cecum, liver, spleen, bursa, and tibia) in a dose-dependent manner. In addition, the more serious feathering abnormalities and feather damage were observed in goslings exposed to a high dose of T-2 toxin (0.8, 1.0, and 2.0 mg/kg), which were mainly sparsely covered with short, dry, rough, curly, and gloss-free feathers on the back. We also found that hypertrophic chondrocytes of the tibial growth plate exhibited abnormal morphology and nuclear consolidation or loss, accompanied by necrosis and excessive apoptosis under 2.0 mg/kg T-2 toxin exposure. Moreover, 2.0 mg/kg T-2 toxin exposure triggered erythropenia, thrombocytosis, alanine aminotransferase, and aspartate aminotransferase activity, as well as high blood urea nitrogen, uric acid, and lactic dehydrogenase levels. Collectively, these data indicate that T-2 toxin had an adverse effect on the growth performance, feather quality, and tibia development, and caused liver and kidney damage and abnormal blood parameters in Yangzhou goslings, providing crucial information toward the prevention and control of T-2 toxin contamination in poultry feed.

Fatty acid profile and safety aspects of the edible oil prepared by artisans' at small-scale agricultural companies

The aim of this study was to analyze the fatty acid (FA) profiles and mycotoxin and polycyclic aromatic hydrocarbon (PAH) concentrations in sea buckthorn (SB1, SB2), flaxseed (FL3, FL4, FL5), hempseed (HE6, HE7, HE8), camelina (CA9, CA10), and mustard (MU11) edible oils, prepared by artisans' by artisanal at small-scale agricultural companies in Lithuania. The dominant FAs were palmitic and oleic acids in SB; palmitic, stearic, oleic, linoleic, and α-linolenic acids in FL; palmitic, stearic, oleic, linoleic, and α-linolenic acids in HE; palmitic, oleic, linoleic, α-linolenic, eicosenoic, and erucic acids in CA; and oleic, linoleic, α-linolenic, eicosenoic, and erucic acids in MU. In SB2 oil samples, T-2 toxin and zearalenone concentrations higher than 1.0 µg/kg were found (1.7 and 3.0 µg/kg, respectively). In sample FL4, an ochratoxin A concentration higher than 1.0 µg/kg was established (1.2 µg/kg); also, in HE8 samples, 2.0 µg/kg of zearalenone was found. None of the tested edible oils exceeded the limits for PAH concentration. Finally, because of the special place of edible oils in the human diet, not only should their contamination with mycotoxins and PAHs be controlled but also their FA profile, as an important safety characteristic, must be taken into consideration to ensure higher safety standards.

Combined effects of arsenic and palmitic acid on oxidative stress and lipid metabolism disorder in human hepatoma HepG2 cells

The toxicity of arsenic (As) can be influenced by many nutrients in food. However, the combined effects and underlying mechanisms of As and palmitic acid (PA) are still unclear. Here, cell viability, oxidative stress, lipids accumulation, gene expression profiles, and metabolome profiles of human hepatoma HepG2 cells exposed to As, PA, and As + PA were analyzed and compared. Results showed that co-exposure of 100 μM PA and 2 μM As induced lower cell viability, higher intracellular reactive oxygen species level, more lipid droplet accumulation, and more intracellular triglyceride contents than As alone or PA alone exposure. High-throughput quantitative PCR and ¹H NMR-based metabolomics analysis showed that co-exposure of As and PA caused all toxic effects on gene expression and metabolome profiles induced by As alone or PA alone exposure, and showed higher toxicities. Gene expression profiles in the As + PA group had higher similarity with those in the As group than the PA group. However, PA played a more important role in metabolism disorder than As in their interactive effects. Oxidative stress and lipid metabolism disorder were found to be the main toxic effects in the As + PA group. Several differentially expressed genes (such as OXR1, OXSR1, INSR, and PPARA) and changed metabolites (such as pyruvate, acetate, and L-phenylalanine) were involved in the combined toxicity of As and PA. This study provides basic information on the interactive effects of As and PA, which is useful for the health risk assessment of As and FFA.

Betulinic Acid Alleviates Spleen Oxidative Damage Induced by Acute Intraperitoneal Exposure to T-2 Toxin by Activating Nrf2 and Inhibiting MAPK Signaling Pathways

T-2 toxin, which is mainly produced by specific strains of Fusarium in nature, can induce immunotoxicity and oxidative stress, resulting in immune organ dysfunction and apoptosis. Betulinic acid (BA), a pentacyclic triterpenoids from nature plants, has been demonstrated to possess immunomodulating and antioxidative bioactivities. The purpose of the study was to explore the effect of BA on T-2 toxin-challenged spleen oxidative damage and further elucidate the underlying mechanism. We found that BA not only ameliorated the contents of serum total cholesterol (TC) and triglyceride (TG) but also restored the number of lymphocytes in T-2 toxin-induced mice. BA dose-dependently reduced the accumulation of reactive oxygen species (ROS), enhanced superoxide dismutase (SOD) activity, and decreased malondialdehyde (MDA) content, as well as increased the total antioxidant capacity (T-AOC) in the spleen of T-2-toxin-exposed mice. Moreover, BA reduced inflammatory cell infiltration in the spleen, improved the morphology of mitochondria and enriched the number of organelles in splenocytes, and dramatically attenuated T-2 toxin-triggered splenocyte apoptosis. Furthermore, administration of BA alleviated the protein phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinases (ERK); decreased the protein expression of kelch-like erythroid cell-derived protein with CNC homology [ECH]-associated protein1 (Keap1); and increased the protein expression of nuclear factor erythroid 2 [NF-E2]-related factor (Nrf2) and heme oxygenase-1 (HO-1) in the spleen. These findings demonstrate that BA defends against spleen oxidative damage associated with T-2 toxin injection by decreasing ROS accumulation and activating the Nrf2 signaling pathway, as well as inhibiting the mitogen-activated protein kinase (MAPK) signaling pathway.

Confrontation assays and mycotoxin treatment reveal antagonistic activities of Trichoderma and the fate of Fusarium mycotoxins in microbial interaction

Mycotoxins are toxic fungal metabolites, contaminating cereal grains in field or during processing and storage periods. These environmental contaminants pose great threats to humans and animals' health due to their toxic effects. Type A trichothecenes, fumonisins and fusaric acid (FA) are commonly detected mycotoxins produced by various Fusarium species. Trichoderma spp. are promising antagonists in agriculture for their activities against plant pathogens, and also regarded as potential candidates for bioremediation of environmental contaminants. Managing toxigenic fungi by antagonistic Trichoderma is regarded as a sustainable and eco-friendly strategy for mycotoxin control. However, the metabolic activities of Trichoderma on natural occurring mycotoxins were less investigated. Our current work comprehensively explored the activities of Trichoderma against type A trichothecenes, fumonisins and FA producing Fusarium species via co-culture competition and indirect volatile assays. Furthermore, we investigated metabolism of type A trichothecenes and FA in Trichoderma isolates. Results indicated that Trichoderma were capable of bio-transforming T-2 toxin, HT-2 toxin, diacetoxyscirpenol and neosolaniol into their glycosylated forms and one Trichoderma strain could bio transform FA into low toxic fusarinol. These findings proved that Trichoderma isolates could manage toxigenic Fusarium via direct competition and volatile-mediated indirect inhibition. In addition, these antagonists possess defensive systems against mycotoxins for self-protection, which enriches our understanding on the interaction mechanism of Trichoderma spp. on toxigenic fungus.

Molecular Aspects of Mycotoxins-A Serious Problem for Human Health

Mycotoxins are toxic fungal secondary metabolities formed by a variety of fungi (moulds) species. Hundreds of potentially toxic mycotoxins have been already identified and are considered a serious problem in agriculture, animal husbandry, and public health. A large number of food-related products and beverages are yearly contaminated by mycotoxins, resulting in economic welfare losses. Mycotoxin indoor environment contamination is a global problem especially in less technologically developed countries. There is an ongoing effort in prevention of mould growth in the field and decontamination of contaminated food and feed in order to protect human and animal health. It should be emphasized that the mycotoxins production by fungi (moulds) species is unavoidable and that they are more toxic than pesticides. Human and animals are exposed to mycotoxin via food, inhalation, or contact which can result in many building-related illnesses including kidney and neurological diseases and cancer. In this review, we described in detail the molecular aspects of main representatives of mycotoxins, which are serious problems for global health, such as aflatoxins, ochratoxin A, T-2 toxin, deoxynivalenol, patulin, and zearalenone.

Mycotoxins: Biotransformation and Bioavailability Assessment Using Caco-2 Cell Monolayer

The determination of mycotoxins content in food is not sufficient for the prediction of their potential in vivo cytotoxicity because it does not reflect their bioavailability and mutual interactions within complex matrices, which may significantly alter the toxic effects. Moreover, many mycotoxins undergo biotransformation and metabolization during the intestinal absorption process. Biotransformation is predominantly the conversion of mycotoxins meditated by cytochrome P450 and other enzymes. This should transform the toxins to nontoxic metabolites but it may possibly result in unexpectedly high toxicity. Therefore, the verification of biotransformation and bioavailability provides valuable information to correctly interpret occurrence data and biomonitoring results. Among all of the methods available, the in vitro models using monolayer formed by epithelial cells from the human colon (Caco-2 cell) have been extensively used for evaluating the permeability, bioavailability, intestinal transport, and metabolism of toxic and biologically active compounds. Here, the strengths and limitations of both in vivo and in vitro techniques used to determine bioavailability are reviewed, along with current detailed data about biotransformation of mycotoxins. Furthermore, the molecular mechanism of mycotoxin effects is also discussed regarding the disorder of intestinal barrier integrity induced by mycotoxins.