Aflatoxin B1 Induces Immunotoxicity through the DNA Methyltransferase-Mediated JAK2/STAT3 Pathway in 3D4/21 Cells

Simultaneously Selective Separation of Zearalenone and Four Aflatoxins From Rice Samples Using Co-Pseudo-Template Imprinted Polymers With MIL-101(Cr)-NH2 as Core

A novel approach for the simultaneous separation of zearalenone (ZEN) and four types of aflatoxins (AFB1, AFB2, AFG1 and AFG2) from rice samples was presented. This approach utilized modified MIL-101(Cr)-NH2 as core, with molecularly imprinted polymers (MIPs) serving as the shell. The MIL-101(Cr)-NH2 was prepared via ring-opening reaction, while the imprinted polymers were synthesized using warfarin and 4-methylumbelliferyl acetate as co-pseudo template, ethylene glycol dimethacrylate as the cross-linker and azobisisobutyronitrile as initiator. The resulting co-pseudo-template-MIPs (CPT-MIPs) were thoroughly characterized and evaluated. Adsorption studies demonstrate that the adsorption process of CPT-MIPs follows a chemical monolayer adsorption mechanism, with imprinted factors ranging from 1.24 to 1.52 and selective factors ranging from 1.29 to 1.52. Self-made columns were prepared, and the method for separation was developed and validated. The limit of detections ranged from 0.12 to 2.09 μg/kg, and the limit of qualifications ranged from 1.2 to 6.25 μg/kg. To assess the reliability of the method, ZEN and AFs were spiked at three different levels, and the recoveries ranged from 79.53 to 94.58%, with relative standard deviations of 2.90-5.78%.

Licochalcone A mitigates aflatoxin B1-induced immunotoxicity via ferroptosis in bursa of broilers and macrophages

Aflatoxin B1 (AFB1) is a mycotoxin which is responsible for severe damage to the immune system of humans and livestock. Licochalcone A (Lico A), a polyphenol derived from turmeric, has attracted great attention due to its wonderful antioxidant properties. Ferroptosis, an iron-dependent cell death related to oxidative stress, which plays a crucial role in the resistance of phytochemical to immune-associated injury. Nevertheless, effects of Lico A on the bursa of broilers exposed to AFB1 remain unclear. In this work, broilers were fed diets supplemented with 2 mg/kg of AFB1 and 50 mg/kg of Lico A. Meanwhile, various concentrations of Lico A and AFB1 (15 μM) were used to stimulate macrophages. These results revealed that AFB1 resulted in more severe bursa atrophy and relative weight reduction; the expression of pro-ferroptosis protein ACSL4 and the content of malondialdehyde (MDA) were significantly elevated, while the expression of anti-ferroptosis proteins GPX4, xCT, FSP1 and the content of Glutathione (GSH) was obviously reduced. However, Lico A treatment effectively reversed these effects in the bursa of broilers. Meanwhile, in bursa and macrophages, Lico A mitigated the expression of AFB1-induced apoptosis-associated protein (Caspase-3, Bax, Bcl-2) as well as antioxidant protein (Nrf2, GCLM, HO-1). Importantly, ferroptosis was also observed in macrophages induced by AFB1. Lico A efficaciously alleviated AFB1-induced mitochondrial membrane potential decrease and reactive oxygen species (ROS) production in macrophages; in contrast, Lico A evidently inhibited AFB1-triggered ROS generation and cytotoxicity, which was disabled by the addition of Erastin. Moreover, Liproxstatin-1 significantly inhibited ROS generation induced by AFB1. In summary, the present study elucidates that the main mechanism by which Lico A attenuates AFB1-induced immunotoxicity is through the suppression of ferroptosis, apoptosis, mitochondrial damage and oxidative stress, which is promising for the improvement of immunotoxic effects of AFB1.

The role of JAK2/STAT3 pathway in non-cytotoxic concentrations of DON-induced aggravation of inflammatory response in IL-10 deficient RAW264.7 cells

Deoxynivalenol (DON) as a mycotoxin was commonly found in food and cereals which can affect immune function and inflammatory response. The majority of foods contain DON at levels below the official limit. This study aimed to evaluate the effects of non-cytotoxic concentration of DON on inflammation and its mechanisms using the IL-10 gene-silenced RAW264.7 cell model. The results showed that a non-cytotoxic concentration of DON at 25 ng/ml aggravated IL-10 knockdown-induced inflammation, which was manifested by increasing IL-1β and TNF-α mRNA expression, migration and phagocytosis, decreasing IL-10 mRNA expression, and enhancing JAK2/STAT3 phosphorylation. Adding JAK2 inhibitor AG490 attenuated the aggravating effect of DON on IL-10 knockdown-induced inflammation. In conclusion, a non-cytotoxic concentration of DON enhances the inflammatory response through the JAK2/STAT3 signaling pathway when inflammation occurs in the body. These results indicated that non-cytotoxic concentrations of DON could aggravate inflammation when inflammation was induced by IL-10 knockdown, which increases vigilance against DON contamination at low concentration especially when an animal's body has inflammation.

Optimizing the degradation of aflatoxin B1 in corn by Trametes versicolor and improving the nutritional composition of corn

BACKGROUND

Corn, being an important grain, is prone to contamination by aflatoxin B1 (AFB1 ), and AFB1 -contaminated corn severely endangers the health of humans and livestock. Trametes versicolor, a fungus that can grow in corn, possesses the ability to directly degrade AFB1 through its laccase. This study aimed to optimize the fermentation conditions for T. versicolor to degrade AFB1 in corn and investigate the effect of T. versicolor fermentation on the nutritional composition of corn. AFB1 -contaminated corn was used as the culture substrate for T. versicolor. A combination of single-factor experiments and response surface methodology was employed to identify the optimal conditions of AFB1 degradation.

RESULTS

The optimal conditions of AFB1 degradation were as follows: 9 days of fermentation, a fermentation temperature of 26.7 °C, a moisture content of 70.5% and an inoculation amount of 4.9 mL (containing 51.99 mg of T. versicolor mycelia). With the optimal conditions, the degradation rate of AFB1 in corn could reach 93.01%, and the dry basis content of protein and dietary fiber in the fermented corn was significantly increased. More importantly, the lysine content in the fermented corn was also significantly increased.

CONCLUSION

This is the first report that direct fermentation of AFB1 -contaminated corn by T. versicolor not only efficiently degrades AFB1 but also improves the nutritional composition of corn. These findings suggest that the fermentation of corn by T. versicolor is a promising, environmentally friendly and efficient approach to degrade AFB1 and improve the nutritional value of corn. © 2023 Society of Chemical Industry.

Immunotoxicity and the mechanisms of aflatoxin B1-induced growth retardation in shrimp and alleviating effects of bile acids

Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins prevalent in the environment and food chain, posing severe health risks to humans and animals. Bile acids are natural detergents synthesized from cholesterol and play a key role in the excretion of toxins in vertebrates. Here, pacific white shrimp (Litopenaeus vannamei) served as an animal model to examine the toxicity mechanisms of AFB1 and assess the potential alleviating effects of bile acids against AFB1. Our results revealed that AFB1 exposure significantly inhibited the growth performance and immune response of shrimp, accompanied by AFB1 accumulation and histological damage. Mechanistically, AFB1-induced DNA damage activated DNA repair mechanisms and induced the arrest of cell cycle via the ATR-cyclin B/cdc2 pathway. Additionally, AFB1 directly suppressed the immune response and growth performance of shrimp by inhibiting Toll and IMD pathways and the secretion of digestive enzymes. Notably, dietary bile acids significantly reduced AFB1 accumulation and alleviated AFB1-induced growth retardation and immunotoxicity in shrimp, and CCKAR, ATR, and Relish may be key mediators of the alleviating effects of bile acids. Our study provided new insights into the toxicity mechanisms of AFB1 in invertebrates and highlighted the potential of bile acids to alleviate AFB1 toxicity.

Effect of Penthorum Chinense Pursh Compound on AFB1-Induced Immune Imbalance via JAK/STAT Signaling Pathway in Spleen of Broiler Chicken

Aflatoxin B1(AFB1) is the main secondary metabolite produced by Aspergillus flavus, which is highly toxic, carcinogenic, mutagenic and teratogenic. It can induce immune imbalance in animals or humans. Penthorum chinense Pursh (PCP) is a traditional herbal plant that has been used as a hepatoprotective drug with a long history in China. Based on the theory of traditional Chinese Medicine, we prepared Penthorum chinense Pursh Compound (PCPC) by combining four herbal medicines: 5 g Penthorum chinense Pursh, 5 g Radix bupleuri, 1 g Artemisia capillaris Thunb and 1 g Radix glycyrrhizae. The role of the Penthorum chinense Pursh Compound (PCPC) in preventing AFB1-induced immune imbalance in broiler chickens was studied. A total of 180 broiler chickens were equally distributed in six groups: controls, AFB1, YCHD and high-, medium- and low-dose PCPC treatment groups. After 28 days, broilers were anesthetized, and serum spleen and thymus samples were collected for analysis. Results show that AFB1 significantly increased and decreased the relative organ weight of the spleen and thymus, respectively. Pathological section of hematoxylin/eosin (H&E) stained spleen sections showed that AFB1 resulted in splenic tissue damage. Both the serum levels of Immunoglobulin A (IgA) and Immunoglobulin G (IgG) were suppressed in the AFB1 group. IL-6 was elevated in the AFB1 group. The balance between pro-inflammatory cytokines (IFN-γ and IL-2) and anti-inflammatory cytokine (IL-4) was disturbed by AFB1. The apoptosis-related protein and JAK/STAT pathway-related gene expression indicated that AFB1-induced apoptosis via JAK/STAT pathway. PCPC has proven its immunoprotective effects by preventing AFB1-induced immune imbalance. PCPC can be applied as a novel immune-modulating medicine in broiler chickens. It can be applied as a novel immune modulator in veterinary clinical practice.

Mitigating the adverse effects of Aflatoxin B1 in LMH, IPEC-J2 and 3D4/21 cells by a novel integrated agent

This study was to evaluate the efficacy of TOXO-XL (XL), an integrated mycotoxin-mitigating agent, on aflatoxin B₁ (AFB₁)-induced damage in Leghorn male hepatoma (LMH), porcine jejunum epithelial cell line (IPEC-J2) and porcine alveolar macrophages (3D4/21) cells, and to explore its potential mechanisms. The results showed that 30% inhibition concentration (IC₃₀) of AFB₁ in LMH, IPEC-J2 and 3D4/21 cells was 0.5, 15.0, and 2.5 mg/L, respectively. Notably, cell viability, ROS, apoptosis and DNA lesion induced by AFB₁ (IC₃₀) could be ameliorated by the supplementation with XL at the dosage of 0.025, 0.025 and 0.005%, respectively. Additionally, the migration and phagocytosis abilities impaired by AFB₁ were also restored by XL in 3D4/21. Further experiments revealed that XL supplementation markedly attenuated AFB₁-induced inflammatory response by decreasing IL-1β, IL-6 and IL-10 in LMH, IL-6 in IPEC-J2 and IL-1β in 3D4/21 cells. Meanwhile, XL supplementation reversed the alterations of BAX, BCL-2 and caspase-3 induced by AFB₁ in the three cells, suggesting that AFB₁-induced apoptosis may be suppressed via the mitochondria-dependent pathway. Furthermore, XL may have a protective effect on the intestinal barrier through the restoration of occludin protein. Conclusively, these findings indicated that XL could alleviate AFB₁-induced cytotoxicity in the three cells, potentially through the regulation of cytokines, ROS, apoptotic and DNA damage signaling.

Mycotoxins Have a Potential of Inducing Cell Senescence: A New Understanding of Mycotoxin Immunotoxicity

Mycotoxins result in immune dysfunction and cause immune diseases in animals and humans. However, the mechanisms of immunotoxicity involved in mycotoxins have not been fully explored, and emerging evidence suggests that these toxins may promote their immunotoxicity via cellular senescence. Mycotoxins induce cell senescence after DNA damage, and activate signaling via the NF-κB and JNK pathways to promote the secretion of senescence-associated secretory phenotype (SASP) cytokines including IL-6, IL-8, and TNF-α. DNA damage can also over-activate or cleave poly (ADP-ribose) polymerase-1 (PARP-1), increase the expression of cell cycle inhibitory proteins p21, and p53, and induce cell cycle arrest and then senescence. These senescent cells further down-regulate proliferation-related genes and overexpress inflammatory factors resulting in chronic inflammation and eventual immune exhaustion. Here we review the underlying mechanisms by which mycotoxins trigger cell senescence and the potential roles of SASP and PARP in these pathways. This work will help to further understand the mechanisms of immunotoxicity involved in mycotoxins.

Role of epigenetics in mycotoxin toxicity: a review

Mycotoxins can induce cell cycle disorders, cell proliferation, oxidative stress, and apoptosis through pathways such as those associated with MAPK, JAK2/STAT3, and Bcl-w/caspase-3, and cause reproductive toxicity, immunotoxicity, and genotoxicity. Previous studies have explored the toxicity mechanism of mycotoxins from the levels of DNA, RNA, and proteins, and proved that mycotoxins have epigenetic toxicity. To explore the toxic effects and mechanisms of these changes in mycotoxins, this paper summarizes the changes in DNA methylation, non-coding RNA, RNA and histone modification induced by several common mycotoxins (zearalenone, aflatoxin B1, ochratoxin A, deoxynivalenol, T-2 toxin, etc.) based on epigenetic studies. In addition, the roles of mycotoxin-induced epigenetic toxicity in germ cell maturation, embryonic development, and carcinogenesis are highlighted. In summary, this review provides theoretical support for a better understanding of the regulatory mechanism of mycotoxin epigenotoxicity and the diagnosis and treatment of diseases.

Evaluation of Effectiveness of a Novel Multicomponent Mycotoxins Detoxification Agent in the Presence of AFB1 and T-2 Toxin on Broiler Chicks

This experimental study was conducted to determine the ability of a novel mycotoxins detoxification agent (MR) at a concentration of 0.2% to reduce the toxicity of aflatoxin B1 (AFB1) or T-2 toxin, alone or in combination, and to examine its effect on performance, pathohistological changes (PH) and the residue of these toxins in the tissues of broiler chicks. A total of 96 broiler chicks were divided into eight equal groups: group C, which served as control (without any additives); group MR, which received the novel detoxification agent (supplemented with 0.2%); group E-I (0.1 mg AFB1/kg of diet); group E-II (0.1 mg AFB1/kg of diet + MR 0.2%); group E-III (0.5 mg T-2 toxin/kg of diet); group E-IV (0.5 mg T-2 toxin/kg of diet + 0.2% MR); group E-V (combination of 0.1 mg AFB1/kg, 0.5 mg T-2 toxin/kg of diet); and group E-VI (combination of 0.1 mg AFB1/kg, 0.5 mg T-2 toxin + 0.2% MR). Results indicate that feeds containing AFB1 and T-2 toxin, alone or in combination, adversely affected the health and performance of poultry. However, the addition of MR to diets containing AFB1 and T-2 toxin singly and in combination exerted a positive effect on body weight, feed intake, weight gain, feed efficiency and microscopic lesions in visceral organs. Residual concentration of AFB1 in liver samples was significantly (p < 0.05) decreased when chicks were fed diets supplemented with 0.2% of MR.

Pterostilbene Ameliorates Fumonisin B1-Induced Cytotoxic Effect by Interfering in the Activation of JAK/STAT Pathway

Fumonisin B1 (FB1) is a mycotoxin that poses a great threat to agricultural production and the health of humans and animals. Pterostilbene (PTE) is a natural plant polyphenolic compound with good anti-inflammatory, antioxidant and cell regeneration effects, yet its effectiveness in treating FB1-induced cytotoxicity remains to be explored. In this study, we used porcine alveolar macrophages (3D4/21) as a model to characterize the cytotoxicity induced by FB1, and to investigate the potential alleviating effect of PTE on FB1-induced cytotoxicity. We demonstrate that FB1 induces cytotoxicity, apoptosis, pro-inflammatory cytokine production and mitochondrial damage, which can be largely recovered by PTE treatment, suggesting the promising application of PTE to treat FB1-induced damage. Mechanistically, FB1 activates the JAK/STAT signaling pathway, while PTE attenuates FB1-induced cytotoxicity through the inhibition of key JAK/STAT genes such as JAK2 and STAT3. Overall, our study characterized the molecular mechanism for FB1-induced cytotoxicity and found PTE to be a promising component which can alleviate FB1-induced cytotoxicity by interfering in the activation of JAK/STAT pathway.

Lactobacillus rhamnosus CY12 Enhances Intestinal Barrier Function by Regulating Tight Junction Protein Expression, Oxidative Stress, and Inflammation Response in Lipopolysaccharide-Induced Caco-2 Cells

The intestinal barrier is vital for preventing inflammatory bowel disease (IBD). The objectives of this study were to assess whether the Lactobacillus rhamnosus CY12 could alleviate oxidative stress, inflammation, and the disruption of tight junction (TJ) barrier functions induced by lipopolysaccharide (LPS), and therefore to explore the potential underlying molecular mechanisms. Our results showed that LPS-induced Cancer coli-2 (Caco-2) cells significantly increased the levels of reactive oxygen species (ROS), lactate dehydrogenase, inflammatory cytokines interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor-α (IL-1β, IL-6, IL-8, and TNF-α), and the cell apoptosis rate while decreasing the levels of TJ proteins occludin, zonula occludens-1 (ZO-1), and claudin and antioxidant enzymes, such as catalase, superoxide dismutase, and glutathione peroxidase(CAT, SOD, and GSH-Px) (p < 0.05). However, Lactobacillus rhamnosus CY12 could relieve cytotoxicity, apoptosis, oxidative stress, and pro-inflammatory cytokine expressions, and also inhibit the Toll-like receptor 4/nuclear factor kappa-B(TLR4/NF-κB) signaling pathway. Furthermore, the gene expression of antioxidant enzymes, as well as the mRNA and protein expressions of TJ proteins, was improved. Particularly, the concentration of 108 cfu/mL significantly prevented the inflammatory injury induced by LPS in Caco-2 cells (p < 0.05). These findings support a potential application of Lactobacillus rhamnosus CY12 as a probiotic to prevent LPS-induced intestinal injury and treat intestinal barrier dysfunction.

Research progress in toxicological effects and mechanism of aflatoxin B1 toxin

Fungal contamination of animal feed can severely affect the health of farm animals, and result in considerable economic losses. Certain filamentous fungi or molds produce toxic secondary metabolites known as mycotoxins, of which aflatoxins (AFTs) are considered the most critical dietary risk factor for both humans and animals. AFTs are ubiquitous in the environment, soil, and food crops, and aflatoxin B₁(AFB₁) has been identified by the World Health Organization (WHO) as one of the most potent natural group 1A carcinogen. We reviewed the literature on the toxic effects of AFB₁ in humans and animals along with its toxicokinetic properties. The damage induced by AFB₁ in cells and tissues is mainly achieved through cell cycle arrest and inhibition of cell proliferation, and the induction of apoptosis, oxidative stress, endoplasmic reticulum (ER) stress and autophagy. In addition, numerous coding genes and non-coding RNAs have been identified that regulate AFB₁ toxicity. This review is a summary of the current research on the complexity of AFB₁ toxicity, and provides insights into the molecular mechanisms as well as the phenotypic characteristics.

Apigeninidin-enriched Sorghum bicolor (L. Moench) extracts alleviate Aflatoxin B1-induced dysregulation of male rat hypothalamic-reproductive axis

We examined the protective effect of the apigeninidin (API)-enriched fraction from Sorghum bicolor sheaths extracts (SBE-05, SBE-06, and SBE-07) against aflatoxin B₁ (AFB₁)-induced dysregulation of male rat's reproductive system that may trigger infertility. Male rats (160 ± 12 g) were treated with AFB₁ (50 µg/kg) along with 5 or 10 mg/kg of SBE-05, SBE-06, and SBE-07 for 28 days. Subsequently, we assessed the reproductive hormone-prolactin, FSH, LH, testosterone levels, and testicular function enzymes. Moreover, we examined rats' testes, epididymis, and hypothalamus for oxidative and inflammatory stress biomarkers, caspase-9 activity and tissues pathology. We observed that comparative to AFB₁ alone treated rats, API co-treatment significantly (p < 0.05) abated the AFB₁-mediated decrease in prolactin and antioxidant defenses and lessened lipid peroxidation (LPO) and reactive oxygen and nitrogen species levels in the examined organs-testes, epididymis, and hypothalamus. API abated AFB₁-induced hormone decreases-testosterone, FSH, and LH; and caused improvement in sperm quantity and quality. API lessened AFB₁-mediated increase in pro-inflammatory cytokine, increased interleukin-10 level, an anti-inflammatory cytokine and reduced caspase-9 activities. In addition, API reduced alterations in the examined tissue histology. Our findings suggest that S. bicolor API-enrich extracts have active antioxidative, antiapoptotic, and anti-inflammatory activities, which can protect against AFB₁-induced dysfunction of the hypothalamic-pituitary-gonadal axis.

The effect of curcumin on some cytokines, antioxidants and liver function tests in rats induced by Aflatoxin B1

Aflatoxins are common food contaminants threating human and animal health. Aflatoxin B1 (AFB1) toxication can lead to important health issues. Recent studies have revealed the therapeutic effect of curcumin (Cur) and have drawn attention in the pharmaceutical industry. The therapeutic efficacy of Cur on AFB1-induced oxidative stress, pro-inflammatory response, and hepatorenal damage has not been adequately studied. This study was conducted to evaluate the protective efficacy of Cur on several lipid peroxidation and antioxidant defense system enzymes, some pro-inflammatory cytokines, and liver function tests in rats suffering from chronic aflatoxicosis induced by AFB1 administered for sixty days. Rats were divided into five groups; Control (K), Dimethyl sulfoxide (D), Curcumin (Cur; 300 mg/kg/day, orally), AFB1 (AF; 250 μg/kg/day, oral) and AFB1+ Curcumin (AF + Cur). Oxidative stress caused by AFB1 caused an increase in Malondialdehyde (MDA), a lipid peroxidation product, and a decrease in glutathione (GSH) and superoxide dismutase (SOD) activities. In addition, AFB1 led to increased levels of pro-inflammatory cytokines such as tumor necrosis factor-a (TNF-a), interleukin-1b (IL-1b), and interleukin-6 (IL-6). Liver function tests after chronic exposure to AFB1 showed that this toxic substance causes liver damage. Concomitant Cur administration normalized AFB1-induced oxidative damage, inflammatory response, and liver functions. This therapeutic effect of Cur on AFB1 was thought to be related to its antioxidant and anti-inflammatory activities. Our results suggest that CUR supplementation in food as it shows beneficial effects particularly on liver impairment exerted by AFB1.

An update on immunotoxicity and mechanisms of action of six environmental mycotoxins

Paradoxically, aflatoxin B1 (AFB1), ochratoxin A (OTA), deoxynivalenol (DON), T-2 toxin (T-2), fumonisin B1 (FB1), and zearalenone (ZEA) have both immunosuppressive and immunostimulatory effects. The immunotoxicity of six mycotoxins exhibits immune suppression or stimulation, which depends on multiple factors. Low doses of mycotoxins can induce an inflammatory response, but elevated levels of ones can induce immunosuppression; long-term instead of short-term mycotoxin exposure is immunosuppressive. These six mycotoxins play anti-inflammatory roles when the immunologic stimulants are present but pro-inflammatory roles when the immunologic stimulants are absent. Pigs are most sensitive animals to mycotoxins, followed by humans and poultry, rodent, and marine organism, and ruminants are the least susceptible. Female animals are more susceptible to mycotoxins than male ones. The immunosuppresion mechanism of mycotoxins are mainly in, oxidative stress, apoptosis and autophagy of immune cells, as well as inhibits the immunity-related signal pathways; and AFB1, OTA, DON, and T-2 induce immunostimulation via directly activating the TLRs/NF-κB pathway and other crossing pathways including cyclooxygenase-2 (COX-2) and mitogen-activated protein kinase (MAPK). This review strongly dispels the viewpoint that "immunotoxicity is equivalent to immunosuppression", clearly demonstrates the mechanistic pathway and how it contributes to immunosuppression or immunostimulation, thereby providing reliable references for future studies.

Immunotoxicity induced by Ivermectin is associated with NF-κB signaling pathway on macrophages

Ivermectin (IVM) has been widely used as a highly effective and broad-spectrum biopesticide in animal husbandry and agriculture. Considering the frequent environmental and occupational exposure, the various toxic effects caused by IVM should be paid more attention. The immune system is a common target of toxins due to its complexity and sensitivity. The toxicity effect of the immune system may lead to increased susceptibility to infections, with potentially fatal consequences. The immunotoxicity of IVM has received little attention, which poses a challenge to the systematic assessment of safety risks. The purpose of this study was to assess the immunotoxicity of the IVM using in vitro cellular assays. We proved that IVM could inhibit the cell viability, induce DNA damage and enhance apoptosis. In addition to the induction of cytotoxicity, IVM has also been shown to reduce the phagocytic capacity and significantly increase the mRNA expression levels of proinflammatory cytokines IL-6, IL-1 β and TNF-α. Intracellular biochemical assay indicated that activation of the NF-κB signaling pathway, overproduction of reactive oxygen species (ROS), release of cytochrome C, DNA double strand damage. These results indicate that IVM can induce immunotoxicity through induction of immune dysfunction and cytotoxicity. In conclusion, this study supports that IVM can be immunotoxic to macrophages in different ways, and draw attention to the potential immunotoxicity of IVM.

In vitro and in vivo evaluation of AFB1 and OTA-toxicity through immunofluorescence and flow cytometry techniques: A systematic review

Due to the globalization, mycotoxins have been considered a major risk to human health being the main contaminants of foodstuffs. Among them, AFB1 and OTA are the most toxic and studied. Therefore, the goal of this review is to deepen the knowledge about the toxicological effects that AFB1 and OTA can induce on human health by using flow cytometry and immunofluorescence techniques in vitro and in vivo models. The examination of the selected reports shows that the majority of them are focused on immunotoxicity while the rest are concerned about nephrotoxicity, hepatotoxicity, gastrointestinal toxicity, neurotoxicity, embryotoxicity, reproductive system, breast, esophageal and lung toxicity. In relation to immunofluorescence analysis, biological processes related to AFB1- and OTA-toxicity were evaluated such as inflammation, neuronal differentiation, DNA damage, oxidative stress and cell death. In flow cytometry analysis, a wide range of assays have been performed across the reviewed studies being apoptosis assay, cell cycle analysis and intracellular ROS measurement the most employed. Although, the toxic effects of AFB1 and OTA have been reported, further research is needed to clarify AFB1 and OTA-mechanism of action on human health.

Aflatoxin B1: metabolism, toxicology, and its involvement in oxidative stress and cancer development

Aflatoxins are a class of carcinogenic mycotoxins produced by Aspergillus fungi, which are widely distributed in nature. Aflatoxin B1 (AFB1) is the most toxic of these compounds and its metabolites have a variety of biological activities, including acute toxicity, teratogenicity, mutagenicity and carcinogenicity, which has been well-characterized to lead to the development of hepatocellular carcinoma (HCC) in humans and animals. This review focuses on the metabolism of AFB1, including epoxidation and DNA adduction, as it concerns the initiation of cancer and the underlying mechanisms. In addition to DNA adduction, inflammation and oxidative stress caused by AFB1 can also participate in the occurrence of cancer. Therefore, the main carcinogenic mechanism of AFB1 related ROS is summarized. This review also describes recent reports of AFB1 exposures in occupational settings. It is hoped that people will pay more attention to occupational health, in order to reduce the incidence of cancer caused by occupational exposure.

Aflatoxin Exposure during Early Life Is Associated with Differential DNA Methylation in Two-Year-Old Gambian Children

Background: DNA methylation is an epigenetic control mechanism that may be altered by environmental exposures. We have previously reported that in utero exposure to the mycotoxin and liver carcinogen aflatoxin B1 from the maternal diet, as measured using biomarkers in the mothers' blood, was associated with differential DNA methylation in white blood cells of 6-month-old infants from The Gambia. Methods: Here we examined aflatoxin B1-associated differential DNA methylation in white blood cells of 24-month-old children from the same population (n = 244), in relation to the child's dietary exposure assessed using aflatoxin albumin biomarkers in blood samples collected at 6, 12 and 18 months of age. HM450 BeadChip arrays were used to assess DNA methylation, with data compared to aflatoxin albumin adduct levels using two approaches; a continuous model comparing aflatoxin adducts measured in samples collected at 18 months to DNA methylation at 24 months, and a categorical time-dose model that took into account aflatoxin adduct levels at 6, 12 and 18 months, for comparison to DNA methylation at 24 months. Results: Geometric mean (95% confidence intervals) for aflatoxin albumin levels were 3.78 (3.29, 4.34) at 6 months, 25.1 (21.67, 29.13) at 12 months and 49.48 (43.34, 56.49) at 18 months of age. A number of differentially methylated CpG positions and regions were associated with aflatoxin exposure, some of which affected gene expression. Pathway analysis highlighted effects on genes involved with with inflammatory, signalling and growth pathways. Conclusions: This study provides further evidence that exposure to aflatoxin in early childhood may impact on DNA methylation.

Effects of Selenium-enriched probiotics on ochratoxin A-induced kidney injury and DNMTs expressions in piglets

Effects of Selenium-enriched probiotics (SP) on ochratoxin A-induced kidney injury, growth performance, antioxidant injury, selenoprotein and DNA methylation transferases (DNMTs) expression of piglets were investigated in the article. A total of 48 piglets were randomly divided into 4 groups and fed with basal diet (Con, 0.15 mg Se/kg and OTA at 0.00 mg/kg), basal diets added with OTA (OTA, 0.40 mg OTA/kg), SP and OTA (SP1, 0.15 mg Se/kg and 0.40 mg OTA/kg), SP and OTA (SP2, 0.30 mg Se/kg and 0.40 mg OTA/kg) respectively for 42 days. From each group, six piglets were randomly selected for blood collection on Days 0 and 42 and three piglets were selected for tissue collection on Day 42.The results showed that OTA at 0.40 mg /kg significantly decreased growth performance of pigs, induced the histopathological lesions of kidney and increased urea and creatine levels of serum, decreased GPx and SOD activities, and increased MDA levels. OTA decreased GPx1, GPx4 and SelS expressions, and increased TR1, DNMT 1, DNMT3a and SOCS3 expressions. Both SP1 and SP2 improved OTA-induced poor growth performance, kidney injury, poor antioxidant statues, GPx1, SelS, TR1, SOCS3, DNMT1 and DNMT3a expressions in kidney of pigs. The effects of SP2 on the above parameters changes were better than that of SP1. SP increased GPx and SOD activities and decreased MDA levels changes induced by OTA treatment. These results suggest that SP may serve as a better feed additive for piglets under mycotoxin contamination environments.

Predicted Aflatoxin B1 Increase in Europe Due to Climate Change: Actions and Reactions at Global Level

Climate change (CC) is predicted to increase the risk of aflatoxin (AF) contamination in maize, as highlighted by a project supported by EFSA in 2009. We performed a comprehensive literature search using the Scopus search engine to extract peer-reviewed studies citing this study. A total of 224 papers were identified after step I filtering (187 + 37), while step II filtering identified 25 of these papers for quantitative analysis. The unselected papers (199) were categorized as "actions" because they provided a sounding board for the expected impact of CC on AFB1 contamination, without adding new data on the topic. The remaining papers were considered as "reactions" of the scientific community because they went a step further in their data and ideas. Interesting statements taken from the "reactions" could be summarized with the following keywords: Chain and multi-actor approach, intersectoral and multidisciplinary, resilience, human and animal health, and global vision. In addition, fields meriting increased research efforts were summarized as the improvement of predictive modeling; extension to different crops and geographic areas; and the impact of CC on fungi and mycotoxin co-occurrence, both in crops and their value chains, up to consumers.

Cuscuta chinensis flavonoids down-regulate the DNA methylation of the H19/Igf2 imprinted control region and estrogen receptor alpha promoter of the testis in bisphenol A exposed mouse offspring

Exposure to the emerging contaminant bisphenol A (BPA) is ubiquitous and associated with reproductive disorders. The BPA effect as an endocrine disruptor is widely known but other mechanisms underlying developmental disease, such as epigenetic modifications, still remain unclear. The objective of this study was to investigate whether Cuscuta chinensis flavonoids (CCFs) can be used as a dietary supplement to reverse BPA-induced epigenetic disorders, by analyzing the molecular processes related to BPA impairment of testicular development. BPA and different concentrations of CCFs were administered to the dams at gestation day (GD) 0.5-17.5. The testis and serum of male mice were collected at postnatal day (PND) 21 and PND 56 for the detection of related indicators. Our results showed that compared with the BPA group, CCFs could significantly increase the serum contents of testosterone (T), estradiol (E2) in males at PND 21 and PND 56, as well as the contents and transcription levels of DNA methyltransferase 3A (Dnmt3A), Dnmt3B in males at PND 21 and that of estrogen receptor alpha (ERα) at PND 56. The expressions of Dnmt1 and ERα at PND 21 and ERβ at both PND 21 and PND 56 in males were significantly decreased with the administration of different concentrations of CCFs (P < 0.01 or P < 0.05). CCFs also significantly inhibited the BPA-induced hypermethylated status of the ERα promoter and H19/Igf2 imprinting control region (ICR) in the testis at PND 56. These results indicated that CCFs could decrease the methylation levels of ERα and H19/Igf2 genes by inhibiting the expression of DNA methyltransferases (DNMTs), thereby decreasing the levels of reproductive hormones and receptors in adult males, and ultimately alleviating the negative effect of BPA on testicular development in male mice.

Combined inhibition of JAK1/2 and DNMT1 by newly identified small-molecule compounds synergistically suppresses the survival and proliferation of cervical cancer cells

Despite substantial advances in treating cervical cancer (CC) with surgery, radiation and chemotherapy, patients with advanced CC still have poor prognosis and significantly variable clinical outcomes due to tumor recurrence and metastasis. Therefore, to develop more efficacious and specific treatments for CC remains an unmet clinical need. In this study, by virtual screening the SPECS database, we identified multiple novel JAK inhibitor candidates and validated their antitumor drug efficacies that were particularly high against CC cell lines. AH057, the best JAK inhibitor identified, effectively blocked the JAK/STAT pathways by directly inhibiting JAK1/2 kinase activities, and led to compromised cell proliferation and invasion, increased apoptosis, arrested cell cycles, and impaired tumor progression in vitro and in vivo. Next, by screening the Selleck chemical library, we identified SGI-1027, a DNMT1 inhibitor, as the compound that displayed the highest synergy with AH057. By acting on a same set of downstream effector molecules that are dually controlled by JAK1/2 and DNMT1, the combination of AH057 with SGI-1027 potently and synergistically impaired CC cell propagation via dramatically increasing apoptotic cell death and cell-cycle arrest. These findings establish a preclinical proof of concept for combating CC by dual targeting of JAK1/2 and DNMT1, and provide support for launching a clinical trial to evaluate the efficacy and safety of this drug combination in patients with CC and other malignant tumors.

Bioactive compounds from Aspergillus niger extract enhance the antioxidant activity and prevent the genotoxicity in aflatoxin B1-treated rats

This study aimed to identify the bioactive compounds of the ethyl acetate extract of Aspergillus niger SH2-EGY using GC-MS and to evaluate their protective role against aflatoxin B1 (AFB1)-induced oxidative stress, genotoxicity and cytotoxicity in rats. Six groups of male Sprague-Dawley rats were treated orally for 4 weeks included the control group, AFB1-treated group (80 μg/kg b.w); fungal extract (FE)-treated groups at low (140) or high dose (280) mg/kg b.w and the groups treated with AFB1 plus FE at the two tested doses. The GC-MS analysis identified 26 compounds. The major compounds found were 1,2,3,4,6-Penta-trimethylsilyl Glucopyranose, Fmoc-L-3-(2-Naphthyl)-alanine, D-(-)-Fructopyranose, pentakis (trimethylsilyl) ether, bis (2-ethylhexyl) phthalate, trimethylsilyl ether-glucitol, and octadecanamide, N-(2- methylpropyl)-N-nitroso. The in vivo results showed that AFB1 significantly increased serum ALT, AST, creatinine, uric acid, urea, cholesterol, triglycerides, LDL, carcinoembryonic antigen, alpha-fetoprotein, interleukin-6, Malondialdehyde, nitric oxide, Bax, caspase-3 and P53 mRNA expression, chromosomal aberrations and DNA fragmentation. It decreased serum TP, albumin, HDL, Bcl-2 mRNA expression, hepatic and renal TAC, SOD and GPx content and induced histological changes in the liver and kidney. FE prevented these disturbances in a dosage-dependent manner. It could be concluded that A. niger SH2-EGY extract is safe a promising agent for pharmaceutical and food industries.

Secondary metabolites from Bacillus sp. MERNA97 extract attenuates the oxidative stress, genotoxicity and cytotoxicity of aflatoxin B1 in rats

This study aimed to determine the bioactive compounds of Bacillus sp. MERNA97 extract and to evaluate their efficacy against the oxidative damage, genotoxicity, chromosomal aberration and DNA fragmentation in rats treated with AFB1. Sixty male Sprague-Dawley rats were divided into 6 groups and treated for 6 weeks and included the control group, AFB1-treated group (80 μg/kg b. w), the groups treated with Bacillus extract (BE) at low (2 mg/kg b.w) or high (4 mg/kg b.w) dose and the groups treated with AFB1 plus BE at the two doses. Blood and tissues samples were collected for different assays. The GC-MS results revealed the isolation of 44 compounds belong to different classes. The in vivo results showed that AFB1 disturbs all the biochemical parameters, oxidative stress markers, cytokines gene expression chromosomal aberration and DNA fragmentation along with the histological changes in the liver tissue. BE at the two tested doses induced a significant improvement in all parameters tested and the histological picture in a dose dependent manner. It could be concluded that the extract of Bacillus sp. MERNA97 isolated from the marine environment in the Red Sea is a promise as a source of novel compounds with therapeutically benefits.

GPx1-mediated DNMT1 expression is involved in the blocking effects of selenium on OTA-induced cytotoxicity and DNA damage

Ochratoxin A (OTA) is a potent nephrotoxin. Selenium (Se) is an essential micronutrient for humans and animals, and plays a key role in antioxidant defense. To date, little is known about the effect of Se on OTA-induced DNA damage. In this study, the protective effects of Se (from selenomethionine) against OTA-induced cytotoxicity and DNA damage were investigated by using PK15 cells as a model. The results showed that OTA at 4.0 μg/mL induced cytotoxicity and DNA damage. Se at 0.5, 1, 2 and 4 μM significantly blocked OTA-induced cytotoxicity and DNA damage. Furthermore, Se blocked the increases of DNMT1, DNMT3a and HDAC1 mRNA and protein expression, reversed the decreases of glutathione peroxidase 1 (GPx1) mRNA and protein expression, and promoted the increases of SOCS3 mRNA and protein expression induced by OTA. Overexpression of GPx1 by pcDNA3.1-GPx1 inhibited the OTA-induced DNMT1 expression, promoted OTA-induced SOCS3 expression, and prevented the OTA-induced cytotoxicity and DNA damage. In contrast, knock-down of GPx1 by using a GPx1-specific siRNA had the opposite effects. The results suggest that GPx1-mediated DNMT1 expression is involved in the blocking effects of selenium on OTA-induced cytotoxicity and DNA damage.

Long-Time Instead of Short-Time Exposure in Vitro and Administration in Vivo of Ochratoxin A Is Consistent in Immunosuppression

Ochratoxin A (OTA) is a mycotoxin produced by Aspergillus and Penicillium, contaminating in a wide variety of foods and feeds. Mycotoxins, including OTA, could cause immunosuppression in almost all previous studies in vivo. However, the vast majority of results in vitro showed that mycotoxins caused immunostimulation. Why the results of studies in vitro are contrary to studies in vivo is unknown. Our study aims to explore the underlying reason and mechanism of the paradoxical effect. In this study, porcine alveolar macrophage cell line 3D4/21 was chosen as an in vitro model and treated with 1.0 μg/mL OTA for different times. Some indexes, such as expression of inflammatory cytokines, migration, phagocytosis, macrophage polarization, autophagy-related proteins, and Akt1 phosphorylation, were detected. The results showed that pro-inflammatory cytokine expression, migration, and phagocytosis were increased, with macrophage polarization to the M1 phenotype at 24 h of OTA exposure. Surprisedly, anti-inflammatory cytokine expression was increased, cell phagocytosis and migration were decreased, and macrophage polarization was switched from M1 to M2 at 72 h of OTA exposure. Furthermore, we found that long-time exposure of OTA also suppressed autophagy, and the autophagy activator blocked the OTA-induced immunosuppression. Phosphorylation of Akt1 plays a positive role in autophagy inhibition. In conclusion, long-time instead of short-time exposure of OTA in vitro induced immunosuppression. The immunosuppression mechanism of OTA in vitro involved inhibition of autophagy through upregulating p-Akt1. Our results provide new insight into research on the mechanism of mycotoxin-induced immunosuppression in vitro.