Protective effect of selenomethionine on intestinal injury induced by T- 2 toxin

Effective protective agents against the organ toxicity of T-2 toxin and corresponding detoxification mechanisms: A narrative review

T-2 toxin is one of the most widespread and toxic fungal toxins in food and feed. It can cause gastrointestinal toxicity, hepatotoxicity, immunotoxicity, reproductive toxicity, neurotoxicity, and nephrotoxicity in humans and animals. T-2 toxin is physicochemically stable and does not readily degrade during food and feed processing. Therefore, suppressing T-2 toxin-induced organ toxicity through antidotes is an urgent issue. Protective agents against the organ toxicity of T-2 toxin have been recorded widely in the literature, but these protective agents and their molecular mechanisms of detoxification have not been comprehensively summarized. In this review, we provide an overview of the various protective agents to T-2 toxin and the molecular mechanisms underlying the detoxification effects. Targeting appropriate targets to antagonize T-2 toxin toxicity is also an important option. This review will provide essential guidance and strategies for the better application and development of T-2 toxin antidotes specific for organ toxicity in the future.

Overview of T-2 Toxin Enterotoxicity: From Toxic Mechanisms and Detoxification to Future Perspectives

Fusarium species produce a secondary metabolite known as T-2 toxin, which is the primary and most harmful toxin found in type A trichothecenes. T-2 toxin is widely found in food and grain-based animal feed and endangers the health of both humans and animals. T-2 toxin exposure in humans and animals occurs primarily through food administration; therefore, the first organ that T-2 toxin targets is the gut. In this overview, the research progress, toxicity mechanism, and detoxification of the toxin T-2 were reviewed, and future research directions were proposed. T-2 toxin damages the intestinal mucosa and destroys intestinal structure and intestinal barrier function; furthermore, T-2 toxin disrupts the intestinal microbiota, causes intestinal flora disorders, affects normal intestinal metabolic function, and kills intestinal epidermal cells by inducing oxidative stress, inflammatory responses, and apoptosis. The primary harmful mechanism of T-2 toxin in the intestine is oxidative stress. Currently, selenium and plant extracts are mainly used to exert antioxidant effects to alleviate the enterotoxicity of T-2 toxin. In future studies, the use of genomic techniques to find upstream signaling molecules associated with T-2 enterotoxin toxicity will provide new ideas for the prevention of this toxicity. The purpose of this paper is to review the progress of research on the intestinal toxicity of T-2 toxin and propose new research directions for the prevention and treatment of T-2 toxin toxicity.

Insights into the intestinal toxicity of foodborne mycotoxins through gut microbiota: A comprehensive review

Mycotoxins, which are fungal metabolites, pose a significant global food safety concern by extensively contaminating food and feed, thereby seriously threatening public health and economic development. Many foodborne mycotoxins exhibit potent intestinal toxicity. However, the mechanisms underlying mycotoxin-induced intestinal toxicity are diverse and complex, and effective prevention or treatment methods for this condition have not yet been established in clinical and animal husbandry practices. In recent years, there has been increasing attention to the role of gut microbiota in the occurrence and development of intestinal diseases. Hence, this review aims to provide a comprehensive summary of the intestinal toxicity mechanisms of six common foodborne mycotoxins. It also explores novel toxicity mechanisms through the "key gut microbiota-key metabolites-key targets" axis, utilizing multiomics and precision toxicology studies with a specific focus on gut microbiota. Additionally, we examine the potential beneficial effects of probiotic supplementation on mycotoxin-induced toxicity based on initial gut microbiota-mediated mycotoxicity. This review offers a systematic description of how mycotoxins impact gut microbiota, metabolites, and genes or proteins, providing valuable insights for subsequent toxicity studies of mycotoxins. Furthermore, it lays a theoretical foundation for preventing and treating intestinal toxicity caused by mycotoxins and advancing food safety practices.

Effects of nano-selenium on cecum microbial community and metabolomics in chickens challenged with Ochratoxin A

Introduction

Ochratoxin A (OTA) is a widely distributed mycotoxin. Nano-selenium (Nano-Se) is an emerging form of selenium known for its superior bioavailability, remarkable catalytic efficiency, and robust adsorbing capacity. Despite these characteristics, its impact on the microbial community and metabolomics in the cecum of chickens exposed to OTA has been infrequently investigated. This research examined the microbiota and metabolomic alterations linked to OTA in chickens, with or without Nano-Se present.

Methods

A cohort of 80 healthy chickens at the age of 1 day was randomly distributed into four groups of equal numbers, namely the Se cohort (1 mg/kg Nano-Se), the OTA cohort (50 μg/kg OTA), the OTA-Se cohort (50 μg/kg OTA + 1 mg/kg Nano-Se), and the control group. Each chicken group's caecal microbiome and metabolome were characterized using 16S rRNA sequencing and Liquid chromatography coupled with mass spectrometry (LC-MS) analyses.

Results and discussion

Our results showed that the on day 21, the final body weight was significantly reduced in response to OTA treatments (p < 0.05), the average daily gain in the OTA group was found to be inferior to the other groups (p < 0.01). In addition, Nano-Se supplementation could reduce the jejunum and liver pathological injuries caused by OTA exposure. The 16S rRNA sequencing suggest that Nano-Se supplementation in OTA-exposed chickens mitigated gut microbiota imbalances by promoting beneficial microbiota and suppressing detrimental bacteria. Moreover, untargeted metabolomics revealed a significant difference in caecal metabolites by Nano-Se pretreatment. Collectively, the dataset outcomes highlighted that Nano-Se augmentation regulates intestinal microbiota and associated metabolite profiles, thus influencing critical metabolic pathways, and points to a possible food-additive product.

Selenomethionine attenuates ochratoxin A-induced small intestinal injury in rabbits by activating the Nrf2 pathway and inhibiting NF-κB activation

The aim of this study was to investigate whether selenomethionine (SeMet) could attenuate intestinal injury in rabbits induced by ochratoxin A (OTA). Sixty 35-day-old IRA rabbits with similar weights were randomly assigned to the control group, OTA group (0.2 mg OTA/kg b.w), OTA+ 0.2 mg/kg Se (0.2 mg OTA/kg b.w + 0.2 mg SeMet/kg feed), OTA+ 0.4 mg/kg Se (0.2 mg OTA/kg b.w + 0.4 mg SeMet/kg feed) and OTA+ 0.6 mg/kg Se (0.2 mg OTA/kg b.w + 0.6 mg SeMet/kg feed). The rabbits were examined after oral administration of different doses of SeMet for 21 days and were intragastrically administered OTA for 7 consecutive days. The results showed that pretreatment with different doses of SeMet protected against the changes in serum biochemical indicators and the decline in production performance caused by OTA exposure. In addition, the activities of SOD, GSH-PX and T-AOC were significantly increased, and the levels of MDA and ROS were decreased after SeMet pretreatment; thus, oxidative damage in rabbit jejunum tissue due to OTA exposure was inhibited. SeMet stimulates Nrf2 and inhibits the NF-κB signalling pathway; the anti-inflammatory response and antioxidative stress in rabbits were improved, and the intestinal barrier damage caused by OTA exposure was improved. In summary, SeMet alleviates OTA-induced intestinal toxicity in rabbits by activating the Nrf2 pathway and inhibiting NF-κB activation. Moreover, 0.4 mg/kg SeMet induced the most significant improvement.

Differential Role of Active Compounds in Mitophagy and Related Neurodegenerative Diseases

Neurodegenerative diseases, such as Alzheimer’s disease or Parkinson’s disease, significantly reduce the quality of life of patients and eventually result in complete maladjustment. Disruption of the synapses leads to a deterioration in the communication of nerve cells and decreased plasticity, which is associated with a loss of cognitive functions and neurodegeneration. Maintaining proper synaptic activity depends on the qualitative composition of mitochondria, because synaptic processes require sufficient energy supply and fine calcium regulation. The maintenance of the qualitative composition of mitochondria occurs due to mitophagy. The regulation of mitophagy is usually based on several internal mechanisms, as well as on signals and substances coming from outside the cell. These substances may directly or indirectly enhance or weaken mitophagy. In this review, we have considered the role of some compounds in process of mitophagy and neurodegeneration. Some of them have a beneficial effect on the functions of mitochondria and enhance mitophagy, showing promise as novel drugs for the treatment of neurodegenerative pathologies, while others contribute to a decrease in mitophagy.

Protective Effect of SeMet on Liver Injury Induced by Ochratoxin A in Rabbits

Ochratoxin A (OTA) is second only to aflatoxin in toxicity among mycotoxins. Recent studies have shown that selenomethionine (SeMet) has a protective effect on mycotoxin-induced toxicity. The purpose of this study was to investigate the protective effect and mechanism of SeMet on OTA-induced liver injury in rabbits. Sixty 35-day-old rabbits with similar body weight were randomly divided into five groups: control group, OTA group (0.2 mg/kg OTA), OTA + 0.2 mg/kg SeMet group, OTA + 0.4 mg/kg SeMet group and OTA + 0.6 mg/kg SeMet group. Rabbits were fed different doses of the SeMet diet for 21 d, and OTA was administered for one week from day 15 (the control group was provided the same dose of NaHCO3 solution). The results showed that 0.4 mg/kg SeMet could significantly improve the liver injury induced by OTA poisoning. SeMet supplementation can improve the changes in physiological blood indexes caused by OTA poisoning in rabbits and alleviate pathological damage to the rabbit liver. SeMet also increased the activities of SOD, GSH-Px and T-AOC and significantly decreased the contents of ROS, MDA, IL-1β, IL-6 and TNF-α, effectively alleviating the oxidative stress and inflammatory response caused by OTA poisoning. In addition, OTA poisoning inhibits Nrf2 and HO-1 levels, ultimately leading to peroxide reaction, while SeMet activates the Nrf2 signaling pathway and enhances the expression of the HO-1 downstream Nrf2 gene. These results suggest that Se protects the liver from OTA-induced hepatotoxicity by regulating Nrf2/HO-1 expression.

Protective and detoxifying effects conferred by selenium against mycotoxins and livestock viruses: A review

Animal feed can easily be infected with molds during production and storage processes, and this can lead to the production of secondary metabolites, such as mycotoxins, which eventually threaten human and animal health. Furthermore, livestock production is also not free from viral infections. Under these conditions, the essential trace element, selenium (Se), can confer various biological benefits to humans and animals, especially due to its anticancer, antiviral, and antioxidant properties, as well as its ability to regulate immune responses. This article reviews the latest literature on the antagonistic effects of Se on mycotoxin toxicity and viral infections in animals. We outlined the systemic toxicity of mycotoxins and the primary mechanisms of mycotoxin-induced toxicity in this analysis. In addition, we pay close attention to how mycotoxins and viral infections in livestock interact. The use of Se supplementation against mycotoxin-induced toxicity and cattle viral infection was the topic of our final discussion. The coronavirus disease 2019 (COVID-19) pandemic, which is currently causing a health catastrophe, has altered our perspective on health concerns to one that is more holistic and increasingly embraces the One Health Concept, which acknowledges the interdependence of humans, animals, and the environment. In light of this, we have made an effort to present a thorough and wide-ranging background on the protective functions of selenium in successfully reducing mycotoxin toxicity and livestock viral infection. It concluded that mycotoxins could be systemically harmful and pose a severe risk to human and animal health. On the contrary, animal mycotoxins and viral illnesses have a close connection. Last but not least, these findings show that the interaction between Se status and host response to mycotoxins and cattle virus infection is crucial.

SeMet attenuates AFB1-induced intestinal injury in rabbits by activating the Nrf2 pathway

The aim of this study was to investigate the role of selenomethionine (SeMet) in alleviating AFB1 induced intestinal injury by inhibiting intestinal oxidative stress. Forty 35-day-old rabbits were divided randomly into 4 groups (control group, AFB1 group, 0.2 mg/kg Se + AFB1 group, 0.4 mg/kg Se + AFB1 group). From the first day of the experiment, the two treatment groups were fed 0.2 mg/kg SeMet or 0.4 mg/kg SeMet daily for 21 days. On the 17th day, all rabbits in the model group and the two treatment groups were given intragastric AFB1 daily for 5 days. The ADG, ADFI and FCR of the rabbits were examined. Rabbit jejunum tissue was collected for hematoxylin- eosin staining (HE), PCNA detection, immunofluorescence and WB. Intestinal tissue IL-1β, IL-6 and TNF-α were examined by enzyme-linked immunosorbent assay (ELISA). The results showed that the production performance was decreased, the levels of ROS and MDA were increased in intestinal tissues, the activity of antioxidant enzymes was decreased and the expression levels of Nrf2 and HO-1 were decreased in AFB1-exposed rabbits. In addition, AFB1 induces an inflammatory response in the jejunum and promotes the expression of TNF-α, IL-6 and IL-1β. SeMet pretreatment significantly improved the performance of the rabbits, alleviated intestinal oxidative stress and the inflammatory response. Therefore, we confirmed that SeMet protects against AFB1 induced oxidative damage and improves productivity in rabbits by activating the Nrf2/HO-1 signaling pathway.

Alterations in the jejunal microbiota and fecal metabolite profiles of rabbits infected with Eimeria intestinalis

Background

Rabbit coccidiosis is a major disease caused by various Eimeria species and causes enormous economic losses to the rabbit industry. Coccidia infection has a wide impact on the gut microbiota and intestinal biochemical equilibrium. In the present study, we established a model of Eimeria intestinalis infection in rabbits to evaluate the jejunal microbiota and fecal metabolite profiles.

Methods

Rabbits in the infected group were orally inoculated with 3 × 10³E. intestinalis oocysts. On the eighth day of infection, jejunal contents and feces were collected for 16S rRNA gene sequencing and liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis, respectively. Jejunum tissues were harvested for hematoxylin and eosin (H&E), periodic acid-Schiff (PAS), and immunohistochemistry (IHC) staining.

Results

Histopathological analysis showed that the whole jejunum was parasitized by E. intestinalis in a range of life cycle stages, and PAS staining showed that E. intestinalis infection caused extensive loss of goblet cells. IHC staining revealed that TNF-α expression was higher in the E. intestinalis infection group. Moreover, both the jejunal microbiota and metabolites significantly altered after E. intestinalis infection. At the genus level, the abundances of Escherichia and Enterococcus significantly increased in the infected group compared with the control group, while those of Oscillospira, Ruminococcus, Bacteroides, Akkermansia, Coprococcus, and Sarcina significantly decreased. In addition, 20 metabolites and two metabolic pathways were altered after E. intestinalis infection, and the major disrupted metabolic pathway was lipid metabolism.

Conclusions

Eimeria intestinalis infection induced intestinal inflammation and destroyed the intestinal homeostasis at the parasitized sites, leading to significant changes in the gut microbiota and subsequent corresponding changes in metabolites.

Graphical Abstract

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.

The Protective Effects of Lactoferrin on Aflatoxin M1-Induced Compromised Intestinal Integrity

Aflatoxin M1 (AFM1), the only toxin with maximum residue levels in milk, has adverse effects on the intestinal barrier, resulting in intestinal inflammatory disease. Lactoferrin (LF), one of the important bioactive proteins in milk, performs multiple biological functions, but knowledge of the protective effects of LF on the compromised intestinal barrier induced by AFM1 has not been investigated. In the present study, results using Balb/C mice and differentiated Caco-2 cells showed that LF intervention decreased AFM1-induced increased intestinal permeability, improved the protein expression of claudin-3, occludin and ZO-1, and repaired the injured intestinal barrier. The transcriptome and proteome were used to clarify the underlying mechanisms. It was found that LF reduced the intestinal barrier dysfunction caused by AFM1 and was associated with intestinal cell survival related pathways, such as cell cycle, apoptosis and MAPK signaling pathway and intestinal integrity related pathways including endocytosis, tight junction, adherens junction and gap junction. The cross-omics analysis suggested that insulin receptor (INSR), cytoplasmic FMR1 interacting protein 2 (CYFIP2), dedicator of cytokinesis 1 (DOCK1) and ribonucleotide reductase regulatory subunit M2 (RRM2) were the potential key regulators as LF repaired the compromised intestinal barrier. These findings indicated that LF may be an alternative treatment for the compromised intestinal barrier induced by AFM1.

Selenomethionine protects oxidative-stress-damaged bone-marrow-derived mesenchymal stem cells via an antioxidant effect and the PTEN/PI3K/AKT pathway

Dental implant surgery is currently a routine therapy for the repair of missing dentition or dentition defects. Both clinical and basic research have elucidated that oxidative stress caused by the accumulation of reactive oxygen species (ROS) for various reasons impairs the process of osteointegration after dental implantation. Therefore, the osteogenic micro-environment must be ameliorated to decrease the damage caused by oxidative stress. Selenomethionine (SEMET) has been reported to play an important role in alleviating oxidative stress and accelerating cell viability and growth. However, it remains unclear whether it exerts protective effects on bone-marrow-derived mesenchymal stem cells (BMSCs) under oxidative stress. In this study, we explored the influence of selenomethionine on the viability and osteogenic differentiation of BMSCs under oxidative stress and the underlying mechanisms. Results showed that 1 μM selenomethionine was the optimum concentration for BMSCs under H₂O₂ stimulation. H₂O₂-induced oxidative stress suppressed the viability and osteogenic differentiation of BMSCs, manifested by the increases in ROS production and cell apoptosis rates, and by the decrease of osteogenic differentiation-related markers. Notably, the aforementioned oxidative damage and osteogenic dysfunction induced by H₂O₂ were rescued by selenomethionine. Furthermore, we found that the PTEN expression level was suppressed and its downstream PI3K/AKT pathway was activated by selenomethionine. However, when PTEN was stimulated, the PI3K/AKT pathway was down-regulated, and the protective effects of selenomethionine on BMSC osteogenic differentiation diminished, while the inhibition of PTEN up-regulated the protective effects of selenomethionine. Together, these results revealed that selenomethionine could attenuate H₂O₂-induced BMSC dysfunction through an antioxidant effect, modulated via the PTEN/PI3K/AKT pathway, suggesting that selenomethionine is a promising antioxidant candidate for reducing oxidative stress during the process of dental implant osteointegration.

Betulinic acid attenuates T-2 toxin-induced cytotoxicity in porcine kidney cells by blocking oxidative stress and endoplasmic reticulum stress

T-2 toxin is highly cytotoxic to animals, which causes damage to animal health and great economic losses to agriculture and livestock production. Betulinic acid (BA), a naturally occurring pentacyclic lupane-type triterpenoid, has various biological and medicinal activities in vivo and in vitro. The objective of the present study was to investigate the toxic effects of T-2 toxin and the reversal effect of BA on porcine kidney (PK-15) cells. We evaluated T-2 toxin-induced apoptotic responses via oxidative stress and endoplasmic reticulum stress pathways by assessing the repair effect of BA in PK-15 cells. The results proved that T-2 toxin (1 μM, treated for 24 h) is highly toxic to PK-15 cells. After pre-treatment with BA (0.25, 0.5, and 1 μM) for 24 h, the cell viabilities were significantly increased, and the lactate dehydrogenase (LDH) in the culture media was dramatically decreased compared to that in the T-2 toxin treatment group. BA also enhanced the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and catalase (CAT) and reduced the production of reactive oxygen species (ROS) and malondialdehyde (MDA) in cells. BA also dose-dependently increased the expression of glucose regulated protein (GRP78), reduced expression of activating transcription factor 4 (ATF4), C/EBP homologous protein (CHOP), the phosphorylation of protein kinase R-like endoplasmic reticulum kinase (PERK), eukaryotic initiation factor 2α (eIF2α), and intracellular Ca²⁺ concentration in a dose-dependent manner. In addition, BA significantly decreased the expression of cleaved-caspase-3 and caspase-12, consequently reducing T-2 toxin-induced PK-15 cell apoptosis in a dose-dependent manner. Collectively, we suggest that BA has a protective effect on T-2 toxin-induced cytotoxicity by ameliorating oxidative stress and endoplasmic reticulum stress in PK-15 cells.

Selenomethionine-Modified Polyethylenimine-Based Nanoparticles Loaded with miR-132-3p Inhibitor-Biofunctionalized Titanium Implants for Improved Osteointegration

Titanium and its alloys have been widely used as bone implants, but for reduced treatment span, improvements are urgently needed to achieve faster and better osteointegration. In this study, we found that miR-132-3p inhibited bone-marrow-derived stem cell (BMSC) osteogenic differentiation via targeting BMP2, and that inhibiting miR-132-3p could significantly improve the osteogenic capability of BMSCs. Moreover, we fabricated a biocompatible selenomethionine (SEMET)-modified polyethylene glycol (PEG)/polyethylenimine (PEI) nanoparticle (SeNP) cross-linked with 0.2% gelatin solutions and delivered miR-132-3p inhibitor to biofunctionalize alkali heat-treated titanium implants, resulting in the development of a novel coating for reverse transfection. The biological performances of PEG/PEI/miR-132-3p inhibitor and SeNP/miR-132-3p inhibitor-biofunctionalized titanium were compared. The biological effects, including cell viability, cytotoxicity, adhesion, cellular uptake, and osteogenic capacity of SeNP/miR-132-3p inhibitor-biofunctionalized titanium implants, were then assessed. Results showed that SeNPs presented appropriate morphology, diameter, and positive zeta potential for efficient gene delivery. The transfection efficiency of the SeNP/miR-132-3p inhibitor was comparable to that of the PEG/PEI/miR-132-3p inhibitor, but the former induced less reactive oxygen species (ROS) production and lower apoptosis rates. Confocal laser scanning microscopy (CLSM) demonstrated that SeNP/miR-132-3p inhibitor nanoparticles released from the titanium surfaces and were taken up by adherent BMSCs. In addition, the release profile showed that transfection could obtain a long-lasting silencing effect for more than 2 weeks. The cell viability, cytotoxicity, and cell spreading of SeNP/miRNA-132-3p inhibitor-biofunctionalized titanium were comparable with those of untreated titanium and the SeNP/miRNA-132-3p inhibitor negative control (NC)-biofunctionalized titanium but resulted in higher ALP activity and osteogenic gene expression levels. In vivo animal studies further certified that SeNP/miRNA-132-3p inhibitor nanoparticles from titanium surfaces promoted osteointegration, which was revealed by microcomputed tomography (micro-CT) and histological observations. Taken together, these findings suggested that selenomethionine-modified PEI-based nanoparticles could achieve better biocompatibility. Moreover, titanium implants biofunctionalized by SeNP/miRNA-132-3p inhibitor nanoparticles might have significant clinical potential for more effective osteointegration.

The Reduction of the Combined Effects of Aflatoxin and Ochratoxin A in Piglet Livers and Kidneys by Dietary Antioxidants

The purpose of this study was to investigate the combined effects of aflatoxin B1 and ochratoxin A on protein expression and catalytic activities of CYP1A2, CYP2E1, CYP3A29 and GSTA1 and the preventive effect of dietary byproduct antioxidants administration against these mycotoxin damage. Three experimental groups (E1, E2, E3) and one control group (C) of piglets after weaning (TOPIGS-40 hybrid) were fed with experimental diets for 30 days. A basal diet containing normal compound feed for starter piglets was used as a control treatment and free of mycotoxin. The experimental groups were fed as follows: E1—basal diet plus a mixture (1:1) of two byproducts (grapeseed and sea buckthorn meal), E2—the basal diet experimentally contaminated with mycotoxins (479 ppb OTA and 62ppb AFB1) and E3—basal diet containing 5% of the mixture (1:1) of grapeseed and sea buckthorn meal and contaminated with the mix of OTA and AFB1. After 4 weeks, the animals were slaughtered, and tissue samples were taken from liver and kidney in order to perform microsomal fraction isolation, followed by protein expression and enzymatic analyses. The protein expressions of CYP2E1 and CYP3A29 were up-regulated in an insignificant manner in liver, whereas in kidney, those of CYP1A2, CYP2E1 and CYP3A29 were down-regulated. The enzymatic activities of CYP1A2, CYP2E1 and CYP3A29 decreased in liver, in a significant manner, whereas in kidney, these increased significantly. The co-presence of the two mycotoxins and the mixture of grape seed and sea buckthorn meal generated a tendency to return to the control values, which suggest that grapeseed and sea buckthorn meal waste represent a promising source in counteracting the harmful effect of ochratoxin A and aflatoxin B.

Neuroimmune disruptions from naturally occurring levels of mycotoxins

Substantial pieces of evidence support the potential of exogenous toxins in disrupting neuroimmune homeostasis. It appears that mycotoxins are one of the noticeable sources of naturally occurring substances dysregulating the immune system, which involves the physiology of many organs, such as the central nervous system (CNS). The induction of inflammatory responses in microglial cells and astrocytes, the CNS resident cells with immunological characteristics, could interrupt the hemostasis upon even with low-level exposure to mycotoxins. The inevitable widespread occurrence of a low level of mycotoxins in foods and feed is likely increasing worldwide, predisposing individuals to potential neuroimmunological dysregulations. This paper reviews the current understanding of mycotoxins' neuro-immunotoxic features under low-dose exposure and the possible ways for detoxification and clearance as a perspective.

Protective effect of selenomethionine on T-2 toxin-induced liver injury in New Zealand rabbits

Background

T-2 toxin is a mycotoxin produced by Fusarium species that is highly toxic to animals. Recent studies have indicated that Selenomethionine (SeMet) have protective effect against mycotoxins-induced toxicity. The aim of the present study was to investigate the protective effect of SeMet on T-2-toxin-induced liver injury in rabbit and explore its molecular mechanism. Fifty rabbits (30 d, 0.5 ± 0.1 kg) were randomly divided into 5 groups: control group, T-2 toxin group, low, medium and high dose SeMet treatment group. The SeMet-treated group was orally pretreated with SeMet (containing selenium 0.2 mg/kg, 0.4 mg/kg and 0.6 mg/kg) for 21 days. On the 17th day, T-2 toxin group and SeMet-treated group were orally administered with T-2 toxin (0.4 mg/kg body weight) for 5 consecutive days.

Results

The results showed that low-dose SeMet significantly improved T-2 toxin-induced liver injury. We found that low-dose SeMet can reduce the level of oxidative stress and the number of hepatocyte apoptosis. Moreover, the levels of Bax, caspase-3 and caspase-9 were significantly reduced and the levels of Bcl-2 were increased.

Conclusions

Therefore, we confirmed that low-dose SeMet may protect rabbit hepatocytes from T-2 toxin by inhibiting the mitochondrial-caspase apoptosis pathway.

Selenium in cereals: Insight into species of the element from total amount

Selenium (Se) is a trace mineral micronutrient essential for human health. The diet is the main source of Se intake. Se-deficiency is associated with many diseases, and up to 1 billion people suffer from Se-deficiency worldwide. Cereals are considered a good choice for Se intake due to their daily consumption as staple foods. Much attention has been paid to the contents of Se in cereals and other foods. Se-enriched cereals are produced by biofortification. Notably, the gap between the nutritional and toxic levels of Se is fairly narrow. The chemical structures of Se compounds, rather than their total contents, contribute to the bioavailability, bioactivity, and toxicity of Se. Organic Se species show better bioavailability, higher nutritional value, and less toxicity than inorganic species. In this paper, we reviewed the total content of Se in cereals, Se speciation methods, and the biological effects of Se species on human health. Selenomethionine (SeMet) is generally the most prevalent and important Se species in cereal grains. In conclusion, Se species should be considered in addition to the total Se content when evaluating the nutritional and toxic values of foods such as cereals.

Betulinic Acid Ameliorates the T-2 Toxin-Triggered Intestinal Impairment in Mice by Inhibiting Inflammation and Mucosal Barrier Dysfunction through the NF-κB Signaling Pathway

T-2 toxin, a trichothecene mycotoxin produced by Fusarium, is widely distributed in crops and animal feed and frequently induces intestinal damage. Betulinic acid (BA), a plant-derived pentacyclic lupane-type triterpene, possesses potential immunomodulatory, antioxidant and anti-inflammatory biological properties. The current study aimed to explore the protective effect and molecular mechanisms of BA on intestinal mucosal impairment provoked by acute exposure to T-2 toxin. Mice were intragastrically administered BA (0.25, 0.5, or 1 mg/kg) daily for 2 weeks and then injected intraperitoneally with T-2 toxin (4 mg/kg) once to induce an intestinal impairment. BA pretreatment inhibited the loss of antioxidant capacity in the intestine of T-2 toxin-treated mice by elevating the levels of CAT, GSH-PX and GSH and reducing the accumulation of MDA. In addition, BA pretreatment alleviated the T-2 toxin-triggered intestinal immune barrier dysregulation by increasing the SIgA level in the intestine at dosages of 0.5 and 1 mg/kg, increasing IgG and IgM levels in serum at dosages of 0.5 and 1 mg/kg and restoring the intestinal C3 and C4 levels at a dosage of 1 mg/kg. BA administration at a dosage of 1 mg/kg also improved the intestinal chemical barrier by decreasing the serum level of DAO. Moreover, BA pretreatment improved the intestinal physical barrier via boosting the expression of ZO-1 and Occludin mRNAs and restoring the morphology of intestinal villi that was altered by T-2 toxin. Furthermore, treatment with 1 mg/kg BA downregulated the expression of p-NF-κB and p-IκB-α proteins in the intestine, while all doses of BA suppressed the pro-inflammatory cytokines expression of IL-1β, IL-6 and TNF-α mRNAs and increased the anti-inflammatory cytokine expression of IL-10 mRNA in the intestine of T-2 toxin-exposed mice. BA was proposed to exert a protective effect on intestinal mucosal disruption in T-2 toxin-stimulated mice by enhancing the intestinal antioxidant capacity, inhibiting the secretion of inflammatory cytokines and repairing intestinal mucosal barrier functions, which may be associated with BA-mediated inhibition of the NF-κB signaling pathway activation.