Bacillus amyloliquefaciens B10 can alleviate liver apoptosis and oxidative stress induced by aflatoxin B1

Baicalin attenuates aflatoxin B1-induced hepatotoxicity via suppressing c-Jun-N-terminal kinase-mediated cell apoptosis

Aflatoxin B1 (AFB1) is classified as a Class I carcinogen and common pollutant in human and animal food products. Prolonged exposure to AFB1 can induce hepatocyte apoptosis and lead to hepatotoxicity. Therefore, preventing AFB1-induced hepatotoxicity remains a critical issue and is of great significance. Baicalin, a polyphenolic compound derived from Scutellaria baicalensis Georgi, has a variety of pharmacodynamic activities, such as antiapoptotic and anticancer activities. This study systematically investigated the alleviating effect of baicalin on AFB1-induced hepatotoxicity from the perspective of apoptosis and explored the possible molecular mechanism. In the normal human liver cell line L02, baicalin treatment significantly inhibited AFB1-induced c-Jun-N-terminal Kinase (JNK) activation and cell apoptosis. In addition, the in vitro mechanism study demonstrated that baicalin alleviates AFB1-induced hepatocyte apoptosis through suppressing the translocation of phosphorylated JNK to the nucleus and decreasing the phosphorylated c-Jun/c-Jun ratio and the Bax/Bcl2 ratio. Molecular docking and drug affinity responsive target stability assays demonstrated that baicalin has the potential to target JNK. This study provides a basis for the therapeutic effect of baicalin on hepatocyte apoptosis caused by AFB1, indicating that the development of baicalin and JNK pathway inhibitors has broad application prospects in the prevention of hepatotoxicity, especially hepatocyte apoptosis.

PFOS Exposure Promotes Hepatotoxicity in Quails by Exacerbating Oxidative Stress and Inflammation-Induced Apoptosis through Activating TLR4/MyD88/NF-κb Signaling

PFOS is a ubiquitous pollutant garnering considerable attention due to its deleterious effects on both human and animal health. Given the poultry industry's intimate link with human health, investigating PFOS's impact on quails is crucial. PFOS readily accumulates in the liver, causing hepatotoxicity, yet its molecular mechanisms remain elusive. In our study, we fed quail diets contaminated with varying PFOS concentrations (12.5, 25, and 50 mg/kg) and observed dose-dependent liver damage in quails. The results show that PFOS damages mitochondrial structure, increases ROS levels, and downregulates antioxidants to promote oxidative stress damage in hepatocytes. PFOS also upregulated pro-inflammatory molecules (TNF-α, IL-1β, and IL-6) while downregulating the anti-inflammatory factor IL-10, activating the TLR4//MyD88/NF-κB signaling pathway, thereby potentiating liver inflammation. Then, oxidative stress and inflammation by PFOS induce apoptosis in quail hepatocytes through the mitochondrial pathway, with severity closely related to hepatotoxicity. In conclusion, PFOS induces mitochondrial apoptosis by exacerbating oxidative stress and inflammation by activating the TLR4/MyD88/NF-κB signaling pathway, ultimately leading to hepatotoxicity in quails.

mtROS-mediated mitophagy is involved in aflatoxin-B1 induced liver injury in ducks

Aflatoxin B1 (AFB1) is highly toxic to the liver and can cause excessive production of mitochondrial reactive oxygen species (mtROS) in hepatocytes, leading to oxidative stress, inflammation, fibrosis, cirrhosis, and even liver cancer. The overproduction of mtROS can induce mitophagy, but whether mtROS and mitophagy are involved in the liver injury induced by AFB1 in ducks remains unclear. In this study, we first demonstrated that overproduction of mtROS and mitophagy occurred during liver injury induced by AFB1 exposure in ducks. Then, by inhibiting mtROS and mitophagy, we found that the damage caused by AFB1 in ducks was significantly alleviated, and the overproduction of mtROS induced by AFB1 exposure could mediate the occurrence of mitophagy. These results suggested that mtROS-mediated mitophagy is involved in AFB1-induced duck liver injury, and they may be the prevention and treatment targets of AFB1 hepatotoxicity.

Salvia miltiorrhiza polysaccharide mitigates AFB1-induced liver injury in rabbits

Aflatoxin B1 (AFB1) is one of the common dietary contaminants worldwide, which can harm the liver of humans and animals. Salvia miltiorrhiza polysaccharide (SMP) is a natural plant-derived polysaccharide with numerous pharmacological activities, including hepatoprotective properties. The purpose of this study is to explore the intervention effect of SMP on AFB1-induced liver injury and its underlying mechanisms in rabbits. The rabbits were administered AFB1 (25 μg/kg/feed) and or treatment with SMP (300, 600, 900 mg/kg/feed) for 42 days. The results showed that SMP effectively alleviated the negative impact of AFB1 on rabbits' productivity by increasing average daily weight gain (ADG) and feed conversion rate (FCR). SMP reduced aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) levels in serum, ameliorating AFB1-induced hepatic pathological changes. Additionally, SMP enhanced superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) activity, and inhibited reactive oxygen species (ROS), malondialdehyde (MDA), 4-Hydroxynonenal (4-HNE), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) expression, thus mitigating AFB1-induced oxidative stress and inflammatory responses. Moreover, SMP upregulated the expression of nuclear factor E2 related factor 2 (Nrf2), heme oxygenase 1 (HO-1), NADPH quinone oxidoreductase 1 (NQO1) and B-cell lymphoma 2 (Bcl2) while downregulating kelch like ECH associated protein 1 (Keap1), cytochrome c (cyt.c), caspase9, caspase3, and Bcl-2-associated X protein (Bax) expression, thereby inhibiting AFB1-induced hepatocyte apoptosis. Consequently, our findings conclude that SMP can mitigate AFB1-induced liver damage by activating the Nrf2/HO-1 pathway and inhibiting mitochondria-dependent apoptotic pathway in rabbits.

Lycopene as a Therapeutic Agent against Aflatoxin B1-Related Toxicity: Mechanistic Insights and Future Directions

Aflatoxin (AFT) contamination poses a significant global public health and safety concern, prompting widespread apprehension. Of the various AFTs, aflatoxin B1 (AFB1) stands out for its pronounced toxicity and its association with a spectrum of chronic ailments, including cardiovascular disease, neurodegenerative disorders, and cancer. Lycopene, a lipid-soluble natural carotenoid, has emerged as a potential mitigator of the deleterious effects induced by AFB1 exposure, spanning cardiac injury, hepatotoxicity, nephrotoxicity, intestinal damage, and reproductive impairment. This protective mechanism operates by reducing oxidative stress, inflammation, and lipid peroxidation, and activating the mitochondrial apoptotic pathway, facilitating the activation of mitochondrial biogenesis, the endogenous antioxidant system, and the nuclear factor erythroid 2-related factor 2 (Nrf2)/kelch-like ECH-associated protein 1 (KEAP1) and peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1) pathways, as well as regulating the activities of cytochrome P450 (CYP450) enzymes. This review provides an overview of the protective effects of lycopene against AFB1 exposure-induced toxicity and the underlying molecular mechanisms. Furthermore, it explores the safety profile and potential clinical applications of lycopene. The present review underscores lycopene's potential as a promising detoxification agent against AFB1 exposure, with the intent to stimulate further research and practical utilization in this domain.

Metagenomic analysis of the intestinal microbiome reveals the potential mechanism involved in Bacillus amyloliquefaciens in treating schistosomiasis japonica in mice

Schistosomiasis japonica is one of the neglected tropical diseases characterized by chronic hepatic, intestinal granulomatous inflammation and fibrosis, as well as dysbiosis of intestinal microbiome. Previously, the probiotic Bacillus amyloliquefaciens has been shown to alleviate the pathological injuries in mice infected with Schistosoma japonicum by improving the disturbance of the intestinal microbiota. However, the underlying mechanisms involved in this process remain unclear. In this study, metagenomics sequencing and functional analysis were employed to investigate the differential changes in taxonomic composition and functional genes of the intestinal microbiome in S. japonicum-infected mice treated with B. amyloliquefaciens. The results revealed that intervention with B. amyloliquefaciens altered the taxonomic composition of the intestinal microbiota at the species level in infected mice and significantly increased the abundance of beneficial bacteria. Moreover, the abundance of predicted genes in the intestinal microbiome was also significantly changed, and the abundance of xfp/xpk and genes translated to urease was significantly restored. Further analysis showed that Limosilactobacillus reuteri was positively correlated with several KEGG Orthology (KO) genes and metabolic reactions, which might play important roles in alleviating the pathological symptoms caused by S. japonicum infection, indicating that it has the potential to function as another effective therapeutic agent for schistosomiasis. These data suggested that treatment of murine schistosomiasis japonica by B. amyloliquefaciens might be induced by alterations in the taxonomic composition and functional gene of the intestinal microbiome in mice. We hope this study will provide adjuvant strategies and methods for the early prevention and treatment of schistosomiasis japonica.

IMPORTANCE

Targeted interventions of probiotics on gut microbiome were used to explore the mechanism of alleviating schistosomiasis japonica. Through metagenomic analysis, there were significant changes in the composition of gut microbiota in mice infected with Schistosoma japonicum and significant increase in the abundance of beneficial bacteria after the intervention of Bacillus amyloliquefaciens. At the same time, the abundance of functional genes was found to change significantly. The abundance of genes related to urease metabolism and xfp/xpk related to D-erythrose 4-phosphate production was significantly restored, highlighting the importance of Limosilactobacillus reuteri in the recovery and abundance of predicted genes of the gut microbiome. These results indicated potential regulatory mechanism between the gene function of gut microbiome and host immune response. Our research lays the foundation for elucidating the regulatory mechanism of probiotic intervention in alleviating schistosomiasis japonica, and provides potential adjuvant treatment strategies for early prevention and treatment of schistosomiasis japonica.

Bacillus amyloliquefaciens SC06 alleviated intestinal damage induced by inflammatory via modulating intestinal microbiota and intestinal stem cell proliferation and differentiation

The aim of our research was to investigate the effects of Bacillus amyloliquefaciens SC06 on growth performance, immune status, intestinal stem cells (ISC) proliferation and differentiation, and gut microbiota in weaned piglets. Twelve piglets (male, 21 days old, 6.11 ± 0.12 kg) were randomly allocated to CON and SC06 (1 × 108 cfu/kg to diet) groups. This experiment lasted three weeks. Our results showed that SC06 increased (P < 0.05) growth performance and reduced the diarrhea rate in weaned piglets. In addition, SC06 increased intestinal morphology and interleukin (IL)-10 levels, and decreased (P < 0.01) necrosis factor (TNF-α) levels in jejunum and serum. Moreover, weaning piglets fed SC06 had a better balance of colonic microbiota, with an increase in the abundance of Lactobacillus. Furthermore, SC06 enhanced ISCs proliferation and induced its differentiation to goblet cells via activating wnt/β-catenin pathway in weaned piglets and intestinal organoid. Taken together, SC06 supplementation improved the growth performance and decreased inflammatory response of piglets by modulating intestinal microbiota, thereby accelerating ISC proliferation and differentiation and promoting epithelial barrier healing.

Therapeutic detoxification of quercetin for aflatoxin B1-related toxicity: Roles of oxidative stress, inflammation, and metabolic enzymes

Aflatoxins (AFTs), a type of mycotoxin mainly produced by Aspergillus parasiticus and Aspergillus flavus, could be detected in food, feed, Chinese herbal medicine, grain crops and poses a great threat to public health security. Among them, aflatoxin B1 (AFB1) is the most toxic one. Exposure to AFB1 poses various health risks to both humans and animals, including the development of chronic inflammatory diseases, cardiovascular diseases, neurodegenerative diseases, and cancer. The molecular mechanisms underlying these risks are intricate and dependent on specific contexts. This review primarily focuses on summarizing the protective effects of quercetin, a natural phenolic compound, in mitigating the toxic effects induced by AFB1 in both in vitro experiments and animal models. Additionally, the review explores the molecular mechanisms that underlie these protective effects. Quercetin has been demonstrated to not only have the direct inhibitory action on the production of AFTs from Aspergillus, both also possess potent ameliorative effects against AFB1-induced cytotoxicity, hepatotoxicity, and neurotoxicity. These effects are attributed to the inhibition of oxidative stress, mitochondrial dysfunction, mitochondrial apoptotic pathway, and inflammatory response. It could also directly target several metabolic enzymes (i.e., CYP3As and GSTA1) to reduce the production of toxic metabolites of AFB1 within cells, then reduce AFB1-induced cytotoxicity. In conclusion, this review highlights quercetin is a promising detoxification agent for AFB1. By advancing our understanding of the protective mechanisms offered by quercetin, we aim to contribute to the development of effective detoxification agents against AFB1, ultimately promoting better health outcomes.

Therapeutic Effect of Natural Products and Dietary Supplements on Aflatoxin-Induced Nephropathy

Aflatoxins are harmful natural contaminants found in foods and are known to be hepatotoxic. However, recent studies have linked chronic consumption of aflatoxins to nephrotoxicity in both animals and humans. Here, we conducted a systematic review of active compounds, crude extracts, herbal formulations, and probiotics against aflatoxin-induced renal dysfunction, highlighting their mechanisms of action in both in vitro and in vivo studies. The natural products and dietary supplements discussed in this study alleviated aflatoxin-induced renal oxidative stress, inflammation, tissue damage, and markers of renal function, mostly in animal models. Therefore, the information provided in this review may improve the management of kidney disease associated with aflatoxin exposure and potentially aid in animal feed supplementation. However, future research is warranted to translate the outcomes of this study into clinical use in kidney patients.

The Ameliorative Role of Lico A on Aflatoxin B1-Triggered Hepatotoxicity Partially by Activating Nrf2 Signal Pathway

Aflatoxin B1 (AFB1) is one of the most harmful and toxic mycotoxins in foods and feeds, posing a serious health risk to both humans and animals, especially its hepatotoxicity. Nuclear factor-erythroid 2-related factor 2 (Nrf2), an important nuclear transcription factor, is generally recognized as a potential target for phytochemicals to ameliorate liver injury. The current study sought to elucidate the molecular processes by which licochalcone A (Lico A), a compound derived from Xinjiang licorice Glycyrrhiza inflate, protects against AFB1 toxicity. In vivo, male wild-type (WT) and Nrf2 knockout (Nrf2-/-) C57BL/6 mice were orally administered AFB1 at 1.5 mg/kg body weight (BW) with or without Lico A at 5 mg/kg. In vitro, AML12 cells were utilized to evaluate the protective effect and mechanism of Lico A against the AFB1-induced hepatotoxicity. Our findings demonstrated that AFB1 caused severe hepatotoxicity, while Lico A treatment successfully relieved the toxicity. Meanwhile, Lico A effectively improved liver injury, inflammatory mediators, oxidative insults, apoptosis, liver fibrosis, and pyroptosis, which contributed to the inhibition of toll receptor 4 (TLR4)-NF-κB/MAPK and NOD-like receptors protein 3 (NLRP3)/caspase-1/GSDMD signaling pathway activation. Furthermore, Lico A was able to enhance the Nrf2 antioxidant signaling pathway. Intriguingly, Lico A still had a protective effect on AFB1-caused liver injury in mice via the inhibition of inflammation and pyroptosis, while apoptosis and liver fibrosis were blocked in the absence of Nrf2. To sum up, the present study first elucidated that Lico A ameliorated AFB1-induced hepatotoxic effects and its main mechanism involved the inhibitory effects on oxidative stress, apoptosis, liver fibrosis, inflammation, and pyroptosis, which might be partially dependent on the regulation of Nrf2. The work may enrich the role and mechanism of Lico A's resistance to liver injury caused by various factors, and its application is promising.

Probiotic Potential of Bacillus amyloliquefaciens Isolated from Tibetan Yaks

The Tibetan livestock sector is now ailing from many infectious ailments brought on by harmful microorganisms. Therefore, this research aimed to assess the probiotic potential and safety of Bacillus amyloliquefaciens isolated from yaks in the Tibet area to provide upper-edge strain resources for probiotics development. The four strains isolated from the intestine of yaks had been identified as Bacillus amyloliquefaciens after the 16S rRNA sequence. The ethanol, bile salt, and acid tolerance revealed that the isolates had significant tolerance levels. The antibiotics susceptibility assay showed that the strains were sensitive to commonly used antibiotics, while the antibacterial assay prevented the isolates from outperforming five harmful bacteria in terms of antibacterial potency. Moreover, it was evident that strain BA5 had the strongest activity to scavenge hydroxyl radical and reduce power. According to the animal experiment, no apparent pathological change was observed in intestinal tissue sections. Furthermore, the strain had a positive effect on promoting the development of jejunal villi referred to its safety. Therefore, more research is required into the bacteriostatic and antioxidant capabilities of isolates in animal production.

Hesperetin protects hippocampal neurons from the neurotoxicity of Aflatoxin B1 in mice

Aflatoxin B1 (AFB1) is a major food and feed pollutant that endangers public health. Previous studies have shown that exposure to AFB1 causes neurotoxicity in the body. However, the mechanism of neurotoxicity caused by AFB1 is not well understood, and finding a workable and practical method to safeguard animals from AFB1 toxicity is essential. This study confirmed that AFB1 caused endoplasmic reticulum stress (ER stress) and apoptosis in hippocampal neurons using C57BL/6 J mice and HT22 cells as models. In vitro experiments showed that the aryl hydrocarbon receptor (AHR) plays a significant role in the cytotoxicity of AFB1. Finally, we assessed how hesperetin protecting against the neurotoxicity caused by AFB1. Our findings demonstrated that AFB1 increased the levels of BAX and Cleaved-Caspase3 proteins, while decreasing the levels of BCL2 protein in the CA1 and CA3 regions of the hippocampus. The AFB1 increased the expression of AHR and activated nuclear translocation. It also elevated the expression levels of Chop, GRP78, p-IRE1/ Xbp1s, and p-PERK/p-EIF2a. Importantly, we also discovered for the first time that blocking AHR in HT22 cells dramatically reduced the level of ER stress and apoptosis caused by AFB1. In vivo and in vitro studies, supplementation of hesperetin effectively reversed AFB1-induced cytotoxicity. We have demonstrated that hesperetin effectively restored the imbalance in the GSH/GST system in HT22 cells treated with AFB1. Furthermore, we observed that elevated GSH levels facilitated the formation of AFB1-GSH complexes, which enhanced the excretion of AFB1. Therefore, hesperetin improves ER stress-induced apoptosis by reducing AFB1 activation of AHR.

Bacillus amyloliquefaciens B10 Alleviates the Immunosuppressive Effects of Deoxynivalenol and Porcine Circovirus Type 2 Infection

As one of the most common mycotoxins, deoxynivalenol (DON) can contaminate a wide range of crops and foods. Porcine circovirus 2 (PCV2) is a kind of immunosuppressive virus, which can cause porcine circovirus associated disease (PCVD) in pig farms infected with PCV2. Pigs are extremely sensitive to DON, and PCV2-infected pig farms are often contaminated with DON. Our previous studies indicated that Bacillus amyloliquefaciens B10 (B10) has the potential to alleviate the toxicity of mycotoxins. The research was aimed at investigating the effects of Bacillus amyloliquefaciens B10 on the immunosuppressive effects caused by both DON and PCV2 infection. The results indicated that the expression of the PCV2 capsid protein CAP was significantly decreased after pretreatment with Bacillus amyloliquefaciens B10. Then, the effects of the Bacillus amyloliquefaciens B10 pretreatment on the type I interferon, antiviral protein and the antiviral signal pathway cGAS-STING was further investigated. The findings displayed that the expression of the type I interferon and antiviral protein were increased, while the IL-10 were decreased after pretreatment with Bacillus amyloliquefaciens B10. The inhibition of DON on the cGAS-STING signal pathway was relieved. Furthermore, it was found that this intervention effect was produced by inhibiting autophagy. In summary, Bacillus amyloliquefaciens B10 can mitigate the immunosuppressive effects of PCV2 and DON by inhibiting the production of autophagy.

Unveiling the hub genes associated with aflatoxin B1-induced hepatotoxicity in chicken

Aflatoxin B1 (AFB1), a ubiquitous and toxic mycotoxin in human food and animal feedstuff, can impair the function and health of some organs, especially the liver. However, the knowledge about the potential mechanisms of AFB1-induced hepatotoxicity in chickens is limited. Therefore, we analyzed the gene expression data of chicken embryo primary hepatocytes (CEPHs) treated with and without AFB1 at the dose of 0.1 μg/mL which were cultured at 37 °C in Medium 199 (Life Technologies, Shanghai, China) with 5.0% CO2 for 48 h. Totally 1,711 differentially expressed genes (DEGs) were identified, in which 1,170 and 541 genes were up- and down-regulated in AFB1-administrated CEPHs compared to the control, respectively. Biological process analysis suggested that these DEGs might take part in angiogenesis, cell adhesion, immune response, cell differentiation, inflammatory response, cell migration regulation, and blood coagulation. Signaling pathways analysis revealed that these DEGs were mainly linked to metabolic pathways, MAPK, TLR2, and actin cytoskeleton regulation pathways. Moreover, the hub genes, including GYS2, NR1H4, ALDH8A1, and ANGPTL3, might participate in AFB1-induced hepatotoxicity. Taken together, our study offers a new insight into the mechanisms of the AFB1-induced hepatotoxicity.

Aflatoxin B1 triggers apoptosis in rabbit hepatocytes via mediating oxidative stress and switching on the mitochondrial apoptosis pathway

Aflatoxin B1 (AFB1) is considered the most toxic carcinogenic compound, and exposure to AFB1 is highly associated with hepatocellular carcinoma. The aim of this study was to investigate the effects of different doses of AFB1 on growth performance and the liver of rabbits, as well as explore its underlying mechanisms. A total of eighty 30-day-old meat rabbits were randomly divided into four treatments. The control group was fed a pollution-free diet, while the AFL, AFM, and AFH groups were fed contaminated diets containing 13 μg/kg, 19 μg/kg, and 25 μg/kg of AFB1, respectively. The results showed that AFB1 had detrimental effects on the production performance of rabbits, resulting in decreased weight gain. Additionally, AFB1 exposure was associated with increased activity of Aspartate aminotransferase (AST) and Alanine aminotransferase (ALT), as well as decreased levels of total protein (TP) and albumin (ALB) in the serum. AFB1 induced the production of reactive oxygen species (ROS) and malondialdehyde (MDA) while inhibiting the activity of glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) activity in liver tissues. AFB1 decreased the mRNA transcription and protein expression of nuclear factor-erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and NAD(P)H dehydrogenase quinone-1 (NQO-1). AFB1 not only decreased the contents of cytochrome P4501A2 (CYP1A2), cytochrome P4502A6 (CYP2A6) and cytochrome P4503A4 (CYP3A4) but also increased the content of AFB1-DNA adducts in the liver. Furthermore, AFB1 enhanced the expression of cytochrome c (cyt-c), caspase-9, caspase-3, and Bcl-2-associated X protein (Bax), while inhibiting the expression of B-cell lymphoma 2 (Bcl-2). Therefore, we demonstrated that AFB1 triggered apoptosis in rabbit hepatocytes via mediating oxidative stress and switching on the mitochondrial apoptosis pathway, and decreased rabbit performance.

Hepatoprotective effects of chlorogenic acid on mice exposed to aflatoxin B1: Modulation of oxidative stress and inflammation

Aflatoxin B1 (AFB1) is widely distributed in crops and feeds, and ingestion of AFB1-contaminated crops is harmful to human/animal health. This study was designed to investigate hepatoprotective effects of chlorogenic acid (CGA), due to its excellent antioxidant and anti-inflammatory activities, on mice exposed to AFB1. Male Kunming mice were orally fed with CGA prior to daily AFB1 exposure for 18 consecutive days. The results showed that CGA treatment reduced the serum activity of aspartate aminotransferase, hepatic malondialdehyde content and pro-inflammatory cytokines synthesis, prevented histopathological changes of the liver, increased hepatic glutathione level, catalase activity and IL10 mRNA expression in mice subjected to AFB1. Taken together, CGA exerted the protective effect on AFB1-induced hepatic damage by modulating redox status and inflammation, suggesting that CGA may be a candidate compound for the treatment of aflatoxicosis.

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.

In Vivo Toxicity Assessment of the Probiotic Bacillus amyloliquefaciens HTI-19 Isolated from Stingless Bee (Heterotrigona itama) Honey

This study evaluated the acute and sub-acute toxicity of B. amyloliquefaciens HTI-19 (isolated from stingless bee honey) in female Sprague Dawley rats. In an acute toxicity study, the rats received a low dosage (1 × 10⁹ CFU·mL^-1), medium dosage (3 × 10⁹ CFU·mL^-1), or high dosage (1 × 10¹⁰ CFU·mL^-1) of B. amyloliquefaciens HTI-19 daily orally by syringe-feeding for 14 days. For the subacute toxicity study, rats received a low dosage (1 × 10⁹ CFU·mL^-1) or a high dosage (1 × 10¹⁰ CFU·mL^-1) for 28 days. The probiotic feeding in acute and sub-acute toxicity studies showed no mortality or significant abnormalities in rats throughout the experimental period. In week 2 of the acute study, the body weight of the rats showed a significant increase (p < 0.05) compared to the control. By gross and microscopic examination of organs, no evidently significant changes were observed in the morphology of organs. Serum biochemical tests and blood hematology tests also revealed no treatment-related changes. Overall, these data indicated that oral administration of B. amyloliquefaciens HTI-19 up to 1 × 10⁹ CFU·mL^-1 for 28 days can be considered safe.

Pharmacokinetics and 28-day repeated-dose toxicity of enniatin B after oral administration in mice

Enniatins are emerging mycotoxins that contaminate foods. The present study investigated the oral pharmacokinetics and 28-day repeated-dose oral toxicity of enniatin B (ENNB) in CD1 (ICR) mice. In the pharmacokinetic study, male mice received a single oral or intravenous dose of ENNB [30 mg/kg body weight (BW) and 1 mg/kg BW, respectively]. After oral dosing, ENNB exhibited 139.9% bioavailability, a 5.1-hr elimination half-life, 5.26% fecal excretion from 4 to 24 h post-dose, and upregulation of Cyp7a1, Cyp2a12, Cyp2b10, and Cyp26a1 in the liver 2 h post-dosing. In the 28-day toxicity study, ENNB was administered to male and female mice by oral gavage at 0, 7.5, 15, and 30 mg/kg BW/day. Females (7.5 and 30 mg/kg) showed dose-unrelated decreased food consumption without accompanying changes in clinical parameters. Males (30 mg/kg) showed low red blood cell counts and high blood urea nitrogen levels and absolute kidney weights; however, other related parameters including the histopathology of systemic organs/tissues were unchanged. These results suggest that ENNB may not induce toxicity after 28 days of oral administration in mice, despite high absorption. The no-observed-adverse-effect level of ENNB after 28 days of repeated oral doses was 30 mg/kg BW/day for both sexes of mice.

Inhibition of aflatoxins on UDP-glucuronosyltransferases (UGTs)

Aflatoxins have been recognized as the most harmful mycotoxins leading to various toxic effects. The present study aims to determine the inhibition behavior of aflatoxins on the activity of the important phase II metabolizing enzymes, UDP-glucuronosyltransferases (UGTs), based on in vitro incubation system of recombinant human UGTs-catalyzed glucuronidation of 4-methylumbelliferone (4-MU). 100 μM AFB1 and AFG1 exhibited extensive inhibition towards UGT isoforms especially UGT1A7 and UGT1A8, with the inhibition ratios to be 71.38%, 72.95% and 72.79% for AFB1 to UGT1A7, AFB1 to UGT1A8 and AFG1 to UGT1A8, respectively. Molecular docking results showed that hydrogen bonds and hydrophobic contacts of the particular structure consisting of double furan ring with double bond contributed to the interaction of aflatoxins and UGTs. Kinetics analysis, including inhibition types and kinetics parameters (K_i), and in vitro-in vivo extrapolation (IVIVE) indicated that there might be a medium possibility of inhibition on UGTs by aflatoxins in vivo. In conclusion, the present study indicated that aflatoxins could possibly disturb endogenous metabolism by inhibiting the activity of UGTs so as to exhibit toxic effects.

Boron exhibits hepatoprotective effect together with antioxidant, anti-inflammatory, and anti-apoptotic pathways in rats exposed to aflatoxin B1

BACKGROUND

Aflatoxins are one of the important environmental factors that pose a risk to living organisms. On the other hand, it has been indicated in research that boron intake has beneficial effects on organisms. In this study, the effect of boron was disclosed in rats exposed to aflatoxin B1 (AFB1), which poses a toxicological risk.

METHODS

A total of 36 male Sprague Dawley rats were separated into 6 groups and 0.125 mg/kg bw AFB1 and 5, 10, or 20 mg/kg bw doses of boron were given orally for 21 days. End of the experiment, biochemical, molecular, and histopathological analyses were performed.

RESULTS

AFB1 treatment increased liver enzyme activities (AST, ALT, and ALP) and malondialdehyde level; on the other hand, it caused a decrease in glutathione level, superoxide dismutase and catalase activities. In addition, the mRNA expression levels of apoptotic (Bax, Caspase-3, Caspase-8, Caspase-9, and p53) and pro-inflammatory (TNF-α and NFκB) genes increased and the mRNA expression of the anti-apoptotic gene (Bcl-2) decreased in liver tissue. Also, AFB1 treatment increased DNA damage and caused histopathological alterations in the liver tissue. Additionally, boron applications at doses of 5, 10, and 20 mg/kg bw given with AFB1 reversed these negative changes.

CONCLUSIONS

As a result, boron exhibited hepatoprotective effect together with antioxidant, anti-inflammatory, and anti-apoptotic effects against AFB1-induced liver damage.

The molecular mechanisms of alpha-lipoic acid on ameliorating aflatoxin B1-induced liver toxicity and physiological dysfunction in northern snakehead (Channa argus)

This research aimed to evaluate the protective mechanism of alpha-lipoic acid (α-LA) on the food-borne aflatoxin B₁ (AFB₁) exposure-induced liver toxicity and physiological dysfunction in the northern snakehead (Channa argus). 480 fish (9.24±0.01 g) were randomly assigned to four treatment groups and fed with four experimental diets for 56 d including the control group (CON), AFB₁ group (200 ppb AFB₁), 600 α-LA group (600 ppm α-LA+200 ppb AFB₁), and 900 α-LA group (900 ppm α-LA+200 ppb AFB₁). The results revealed that 600 and 900 ppm α-LA attenuated AFB₁-induced growth inhibition and immunosuppression in northern snakehead. 600 ppm α-LA significantly decreased the serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase levels, and AFB₁ bioaccumulation, and attenuated the changes of hepatic histopathological and ultrastructure induced by AFB₁. Moreover, 600 and 900 ppm α-LA significantly up-regulated phase I metabolism genes (cytochrome P450-1a, 1b, and 3a) mRNA expression, inhibited the levels of malondialdehyde, 8‑hydroxy-2 deoxyguanosine and reactive oxygen species in the liver. Notably, 600 ppm α-LA significantly up-regulated the expression levels of nuclear factor E2 related factor 2 and its related downstream antioxidant molecules (heme oxygenase 1 and NAD(P)H: quinone oxidoreductase 1, etc.), increased the phase II detoxification enzyme-related molecules (glutathione-S-transferase and glutathione), antioxidant parameters (catalase and superoxide dismutase, etc.), and the expressions of Nrf2 and Ho-1 protein in the presence of AFB₁ exposure. Furthermore, 600 and 900 ppm α-LA significantly reduced the characteristic indices of AFB₁-induced endoplasmic reticulum stress (glucose-regulated protein 78 and inositol requiring enzyme 1, etc.), apoptosis (caspase-3 and cytochrome c, etc.) and inflammation (nuclear factor kappa B and tumor necrosis factor α, etc.), while increased the B-cell lymphoma-2 and inhibitor of κBα in the liver after being exposed to AFB₁. To summarize, the above results indicate that dietary α-LA could modulate the Nrf2 signaling pathway to ameliorate AFB₁-induced growth inhibition, liver toxicity, and physiological dysfunction in northern snakehead. Although the concentration of α-LA increased to 900 ppm from 600 ppm, the protective effects of the 900 ppm α-LA do not show an advantage over the 600 ppm α-LA, and even show inferiority in some respects. So that the recommended concentration of α-LA is 600 ppm. The present study provides the theoretical foundation for developing α-LA as the prevention and treatment of AFB₁-induced liver toxicity in aquatic animals.

Immunotoxicity of Three Environmental Mycotoxins and Their Risks of Increasing Pathogen Infections

Aflatoxin B1 (AFB1), ochratoxin A (OTA), and deoxynivalenol (DON) are the three mycotoxins that have received the most scholarly attention and have been tested most routinely in clinics. These mycotoxins not only suppress immune responses but also induce inflammation and even increase susceptibility to pathogens. Here, we comprehensively reviewed the determining factors for the bidirectional immunotoxicity of the three mycotoxins, their effects on pathogens, and their action mechanisms. The determining factors include mycotoxin exposure doses and times, as well as species, sex, and some immunologic stimulants. Moreover, mycotoxin exposure can affect the infection severity of some pathogens, including bacteria, viruses, and parasites. Their specific action mechanisms include three aspects: (1) mycotoxin exposure directly promotes the proliferation of pathogenic microorganisms; (2) mycotoxins produce toxicity, destroy the integrity of the mucosal barrier, and promote inflammatory response, thereby improving the susceptibility of the host; (3) mycotoxins reduce the activity of some specific immune cells and induce immune suppression, resulting in reduced host resistance. The present review will provide a scientific basis for the control of these three mycotoxins and also provide a reference for research on the causes of increased subclinical infections.

Curcumin attenuates AFB1-induced duck liver injury by inhibiting oxidative stress and lysosomal damage

Aflatoxin B1 (AFB1), as the most toxic secondary metabolite produced by Aspergillus flavus, is a serious threat to human and animal health. Curcumin, a polyphenol from the plant turmeric, has demonstrated unique anti-damage properties in several studies. But, its ability to alleviate AFB1-induced liver damage in ducks and the underlying mechanisms are not completely elucidated. In this study, we investigated the intervention of curcumin on AFB1-induced hepatotoxicity in ducks. Research data showed that the combination of curcumin and AFB1 alleviated oxidative stress, reduced malondialdehyde (MDA) accumulation and relieved hepatotoxicity after 28 days of treatment, compared with AFB1. Also, curcumin upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant enzymes (SOD, HO-1), which enhanced the antioxidant capacity of the liver. In addition, curcumin inhibited AFB1-induced lysosomal damage in the liver, with the character of reduced lysosomal membrane permeabilization, restored autophagic flux, and promoted lysosomal biogenesis, thereby enhancing the self-protective capacity of the liver. In conclusion, our results suggest that curcumin alleviates AFB1-induced duck hepatotoxicity by inhibiting oxidative stress and lysosomal damage.

Oral administration of Bacillus cereus GW-01 alleviates the accumulation and detrimental effects of β-cypermethrin in mice

Pyrethroid insecticides negatively affect feed conversion, reproductive fitness, and food safety in exposed animals. Although probiotics have previously been widely studied for their effect on gut health, comparatively little is known regarding the efficacy of probiotic administration in specifically reducing pesticide toxicity in mice. We demonstrated that oral administration of a β-cypermethrin (β-CY)-degrading bacterial strain (Bacillus cereus GW-01) to β-CY-exposed mice reduced β-CY levels in the liver, kidney, brain, blood, lipid, and feces (18%-53%). Additionally, co-administration of strain GW-01 to β-CY-exposed mice reduced weight loss (22%-31%) and improved liver function (15%-19%) in mice. Additionally, mice receiving GW-01 had near-control levels of numerous β-CY-affected gut microbial taxa, including Muribaculaceae, Alloprevotella, Bacteroides, Dubosiella, and Alistipes. The survival and β-CY biosorption of GW-01 in simulated gastrointestinal fluid conditions were significantly higher than E. coli. These results suggested that GW-01 can reduce β-CY accumulation and alleviate the damage in mice. This study is the first to demonstrate that a probiotic strain can reduce the toxicity of β-CY in mice.

Epigallocatechin Gallate and Glutathione Attenuate Aflatoxin B1-Induced Acute Liver Injury in Ducklings via Mitochondria-Mediated Apoptosis and the Nrf2 Signalling Pathway

Aflatoxin B1 (AFB1) exists widely in feed and food with severe hazards, posing a serious threat to human and animal health. Epigallocatechin gallate (EGCG) and glutathione (GSH) have been reported as having anti-oxidative and other functions. The present study aimed to investigate the detoxification effect of EGCG and GSH alone or in combination on AFB1 exposure in ducklings. Fifty one-day-old male ducklings were randomly assigned into five experimental groups (n = 10): 1. Control (CTR); 2. 0.3 mg/kg BW AFB1 (AFB1); 3. 0.3 mg/kg BW AFB1 + 100 mg/kg BW EGCG (AFB1 + EGCG); 4. 0.3 mg/kg BW AFB1 + 30 mg/kg BW GSH (AFB1 + GSH); 5. 0.3 mg/kg BW AFB1 + 100 mg/kg BW EGCG + 30 mg/kg BW GSH (AFB1 + EGCG + GSH). The experiment lasted for seven days. Compared with the CTR group, AFB1 reduced growth performance, total serum protein and albumin content, increased serum enzyme activity (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase), and caused pathological damage to the ducklings' livers. AFB1 exposure increased malondialdehyde content and decreased superoxide dismutase, total antioxidant capacity, catalase, glutathione peroxidase activities, and glutathione content in the liver. EGCG and GSH alone or in combination mitigated these adverse effects. Meanwhile, EGCG and GSH attenuate apoptosis of hepatocytes, and regulated AFB1-induced changes in the abundance of genes contained in the Keap1/Nrf2 signalling and apoptotic pathways. Collectively, these results suggest that EGCG and GSH alleviate the hepatocyte injury induced by AFB1 by inhibiting oxidative stress and attenuating excessive mitochondria-mediated apoptosis.

Aflatoxin B1 Exposure in Sheep: Insights into Hepatotoxicity Based on Oxidative Stress, Inflammatory Injury, Apoptosis, and Gut Microbiota Analysis

The widespread fungal toxin Aflatoxin B₁ (AFB₁) is an inevitable pollutant affecting the health of humans, poultry, and livestock. Although studies indicate that AFB₁ is hepatotoxic, there are few studies on AFB₁-induced hepatotoxicity in sheep. Thus, this study examined how AFB₁ affected sheep liver function 24 h after the animals received 1 mg/kg bw of AFB₁ orally (dissolved in 20 mL, 4% v/v ethanol). The acute AFB₁ poisoning caused histopathological injuries to the liver and increased total bilirubin (TBIL) and alkaline phosphatase (AKP) levels. AFB₁ also markedly elevated the levels of the pro-inflammatory cytokines TNF-α and IL-6 while considerably reducing the expression of antioxidation-related genes (SOD-1 and SOD-2) and the anti-inflammatory gene IL-10 in the liver. Additionally, it caused apoptosis by dramatically altering the expression of genes associated with apoptosis including Bax, Caspase-3, and Bcl-2/Bax. Notably, AFB₁ exposure altered the gut microbiota composition, mainly manifested by BF311 spp. and Alistipes spp. abundance, which are associated with liver injury. In conclusion, AFB₁ can cause liver injury and liver dysfunction in sheep via oxidative stress, inflammation, apoptosis, and gut-microbiota disturbance.

Dietary aflatoxin B1 caused the growth inhibition, and activated oxidative stress and endoplasmic reticulum stress pathway, inducing apoptosis and inflammation in the liver of northern snakehead (Channa argus)

The purpose of this study was to investigate the effects of dietary aflatoxin B₁ (AFB₁) on growth performance and AFB₁ biotransformation, and hepatic oxidative stress, endoplasmic reticulum (ER) stress, apoptosis, and inflammation in northern snakehead (Channa argus). A total of 600 northern snakeheads (7.52 ± 0.02 g) were divided into five groups (three replicates/group) and fed the diets with AFB₁ at concentrations of 0, 50, 100, 200, and 400 ppb for 8 weeks. The results demonstrated that dietary AFB₁ (≥ 200 ppb) reduced FBW, WG, and SGR. 100, 200, and 400 ppb AFB₁ treatment groups significantly decreased the PER, CRP, C3, C4, IgM, and LYS levels in northern snakehead, while FCR was significant increased. Moreover, dietary AFB₁ (100, 200, and 400 ppb) increased cyp1a, cyp1b (except 400 ppb), and cyp3a mRNA expression levels, while reducing the GST enzymatic activity and mRNA expression levels in northern snakehead. Furthermore, AFB₁ (≥ 100 ppb) increased ROS, MDA, and 8-OHdG levels, and grp78, ire1, perk, jnk, chop, and traf2 mRNA expression levels, and decreased SOD, CAT, GSH-Px, and GSH (except 100 ppb) levels and the gene expression levels of cat, gsh-px (except 100 ppb), and Cu/Zn sod. In addition, AFB₁ (100, 200, and 400 ppb) up-regulated the cyt-c, bax, cas-3, and cas-9 mRNA levels in the liver, while down-regulating the bcl-2 expression levels. Meanwhile, the expression levels of nf-κb, tnf-α (except 100 ppb), il-1β, and il-8 in the liver were up-regulated in AFB₁ treatment groups (≥ 100 ppb), while the iκbα mRNA levels were down-regulated. In summary, dietary AFB₁ reduced growth performance and humoral immunity in northern snakehead. Meanwhile, the cyclic occurrence of oxidative stress and ER stress, and induced apoptosis and inflammation, is one of the main reasons for AFB₁-induced liver injury in the northern snakehead, which will provide valuable information and a fresh perspective for further research into AFB₁-induced liver injury in fish.

Aflatoxin B1 Toxicity and Protective Effects of Curcumin: Molecular Mechanisms and Clinical Implications

One of the most significant classes of mycotoxins, aflatoxins (AFTs), can cause a variety of detrimental outcomes, including cancer, hepatitis, aberrant mutations, and reproductive issues. Among the 21 identified AFTs, aflatoxin B1 (AFB1) is the most harmful to humans and animals. The mechanisms of AFB1-induced toxicity are connected to the generation of excess reactive oxygen species (ROS), upregulation of CYP450 activities, oxidative stress, lipid peroxidation, apoptosis, mitochondrial dysfunction, autophagy, necrosis, and inflammatory response. Several signaling pathways, including p53, PI3K/Akt/mTOR, Nrf2/ARE, NF-κB, NLRP3, MAPKs, and Wnt/β-catenin have been shown to contribute to AFB1-mediated toxic effects in mammalian cells. Curcumin, a natural product with multiple therapeutic activities (e.g., anti-inflammatory, antioxidant, anticancer, and immunoregulation activities), could revise AFB1-induced harmful effects by targeting these pathways. Therefore, the potential therapeutic use of curcumin against AFB1-related side effects and the underlying molecular mechanisms are summarized. This review, in our opinion, advances significant knowledge, sparks larger discussions, and drives additional improvements in the hazardous examination of AFTs and detoxifying the application of curcumin.

Thymol Alleviates LPS-Induced Liver Inflammation and Apoptosis by Inhibiting NLRP3 Inflammasome Activation and the AMPK-mTOR-Autophagy Pathway

Thymol is a natural antibacterial agent found in the essential oil extracted from thyme, which has been proven to be beneficial in food and medicine. Meanwhile, the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome and autophagy have been reported to play key roles in the progression of liver injury. However, the effects of thymol on the NLRP3 inflammasome and autophagy in protecting the liver remain unclear. The present study used a mouse model with liver injury induced by lipopolysaccharides (LPS) to investigate the regulatory mechanisms of thymol. We found that thymol alleviated LPS-induced liver structural damage, as judged by reduced inflammatory cell infiltration and improved structure. In addition, elevated levels of the liver damage indicators (alanine transaminase (ALT), aspartate transaminase (AST), and total bilirubin (TBIL)) dropped after thymol administration. The mRNA and protein expression of inflammatory cytokines (tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-22), apoptosis-related genes (caspase3 and caspase9), and the activity of apoptosis-related genes (caspase3 and caspase9) were increased in LPS-treated livers, whereas the changes were alleviated after thymol administration. Thymol inhibited LPS-induced increment in lactate dehydrogenase (LDH) activity in primary hepatocytes of the mouse. In addition, thymol protected mice from liver injury by inhibiting NLRP3 inflammasome activation induced by LPS. Mechanistically, the present study indicates that thymol has liver protective activity resulting from the modulation of the AMP-activated protein kinase—mammalian target of rapamycin (AMPK–mTOR) to regulate the autophagy pathway, hence curbing inflammation.

Biocontrol Ability of the Bacillus amyloliquefaciens Group, B. amyloliquefaciens, B. velezensis, B. nakamurai, and B. siamensis, for the Management of Fungal Postharvest Diseases: A Review

The Bacillus amyloliquefaciens group, composed of B. amyloliquefaciens, B. velezensis, B. nakamurai, and B. siamensis, has recently emerged as an interesting source of biocontrol agents for the management of pathogenic fungi. In this review, all the reports regarding the ability of these species to control postharvest fungal diseases have been covered for the first time. B. amyloliquefaciens species showed various antifungal mechanisms, including production of antifungal lipopeptides and volatile organic compounds, competition for nutrients, and induction of disease resistance. Most reports discussed their use for the control of fruit diseases. Several strains were studied in combination with additives, improving their inhibitory efficacies. In addition, a few strains have been commercialized. Overall, studies showed that B. amyloliquefaciens species are a suitable environmentally friendly alternative for the control of postharvest diseases. However, there are still crucial knowledge gaps to improve their efficacy and host range.

Alleviation of Oral Exposure to Aflatoxin B1-Induced Renal Dysfunction, Oxidative Stress, and Cell Apoptosis in Mice Kidney by Curcumin

Aflatoxin B1 is a contaminant widely found in food and livestock feed, posing a major threat to human and animal health. Recently, much attention from the pharmaceutical and food industries has been focused on curcumin due to its strong antioxidant capacity. However, the therapeutic impacts and potential mechanisms of curcumin on kidney damage caused by AFB1 are still incomplete. In this study, AFB1 triggered renal injury in mice, as reflected by pathological changes and renal dysfunction. AFB1 induced renal oxidative stress and interfered with the Keap1–Nrf2 pathway and its downstream genes (CAT, SOD1, NQO1, GSS, GCLC, and GCLM), as manifested by elevated oxidative stress metabolites and reduced antioxidant enzymes activities. Additionally, AFB1 was found to increase apoptotic cells percentage in the kidney via the TUNEL assay, along with increased expression of Cyt-c, Bax, cleaved-Caspase-3, Caspase-9, and decreased expression of Bcl-2 at the transcriptional and protein levels; in contrast, for mice given curcumin, there was a significant reversal in kidney coefficient, biochemical parameters, pathological changes, and the expression of genes and proteins involved in oxidative stress and apoptosis. These results indicate that curcumin could antagonize oxidative stress and apoptosis to attenuate AFB1-induced kidney damage.

Citrinin-Induced Hepatotoxicity in Mice Is Regulated by the Ca2+/Endoplasmic Reticulum Stress Signaling Pathway

Citrinin (CTN) is a mycotoxin found in crops and agricultural products and poses a serious threat to human and animal health. The aim of this study is to investigate the hepatotoxicity of CTN in mice and analyze its mechanisms from Ca2+-dependent endoplasmic reticulum (ER) stress perspective. We showed that CTN induced histopathological damage, caused ultrastructural changes in liver cells, and induced abnormal values of biochemical laboratory tests of some liver functions in mice. Treatment with CTN could induce nitric oxide (NO), malondialdehyde (MDA), and reactive oxygen species (ROS) accumulation in mice, accompanied with losses of activities of superoxide dismutase (SOD) and catalase (CAT), levels of glutathione (GSH), and capacities of total antioxidant (T-AOC), resulting in oxidative stress in mice. Furthermore, CTN treatment significantly increased Ca2+ accumulation, upregulated protein expressions of ER stress-mediated apoptosis signal protein (glucose regulated protein 78 (GRP78/BIP), C/EBP-homologous protein (CHOP), Caspase-12, and Caspase-3), and induced hepatocyte apoptosis. These adverse effects were counteracted by 4-phenylbutyric acid (4-PBA), an ER stress inhibitor. In summary, our results showed a possible underlying molecular mechanism for CTN that induced hepatocyte apoptosis in mice by the regulation of the Ca2+/ER stress signaling pathway.

Aflatoxin B1 causes oxidative stress and apoptosis in sheep testes associated with disrupting rumen microbiota

Aflatoxin B1 (AFB1) is an unavoidable environmental pollutant commonly found in feed and foodstuffs. It is the most toxic one of all the aflatoxins, which can cause severe impairment to testicular development and function. Yet, the underlying mechanisms of reproductive toxicity in rams sheep remain inconclusive. The study was designed to explore the effects of AFB1 on sheep testes through rumen-microbiota, oxidative stress and apoptosis. Six-month-old male Dorper rams (n = 6) were orally administrated with 1.0 mg/kg AFB1 (dissolved in 20 mL 4% ethanol) 24 h before the experiment. At the same time, rams in the control group (n = 6) were intragastrically administrated with 20 mL 4% ethanol. It was observed that acute AFB1 poisoning had significant (p < 0.05) toxin residue in the testis and could cause testicular histopathological damage. AFB1 stimulated the secretion of plasma testosterone level through regulating testosterone synthesis-related genes (StAR, 3β-HSD, CYP11A1, and CYP17A1), which are accompanied by the increase of oxidative stress and testicular apoptosis that had a close relationship with the regulation of testosterone secretion. Interestingly, we observed rumen dysbacteriosis and decreased the abundances of Prevotella, Succiniclasticum, CF231, Ruminococcus, and Pseudobutyrivibrio in AFB1-exposed sheep, which were negatively correlated to the testosterone synthesis-related gene levels. Taken together, our findings indicated that AFB1 induced testicular damage and testicular dysfunction, which is related to testicular oxidative stress and apoptosis involved in rumen dysbacteriosis in sheep.

Metabolomic Analysis Reveals the Mechanisms of Hepatotoxicity Induced by Aflatoxin M1 and Ochratoxin A

Aflatoxin M1 (AFM1) is the only toxin with the maximum residue limit in milk, and ochratoxin A (OTA) represents a common toxin in cereals foods. It is common to find the co-occurrence of these two toxins in the environment. However, the interactive effect of these toxins on hepatoxicity and underlying mechanisms is still unclear. The liver and serum metabolomics in mice exposed to individual AFM1 at 3.5 mg/kg b.w., OTA at 3.5 mg/kg b.w., and their combination for 35 days were conducted based on the UPLC-MS method in the present study. Subsequent metabolome on human hepatocellular liver carcinoma (Hep G2) cells was conducted to narrow down the key metabolites. The phenotypic results on liver weight and serum indicators, such as total bilirubin and glutamyltransferase, showed that the combined toxins had more serious adverse effects than an individual one, indicating that the combined AFM1 and OTA displayed synergistic effects on liver damage. Through the metabolic analysis in liver and serum, we found that (i) a synergistic effect was exerted in the combined toxins, because the number of differentially expressed metabolites on combination treatment was higher than the individual toxins, (ii) OTA played a dominant role in the hepatoxicity induced by the combination of AFM1, and OTA and (iii) lysophosphatidylcholines (LysoPCs), more especially, LysoPC (16:1), were identified as the metabolites most affected by AFM1 and OTA. These findings provided a new insight for identifying the potential biomarkers for the hepatoxicity of AFM1 and OTA.

Application of triple co-cultured cell spheroid model for exploring hepatotoxicity and metabolic pathway of AFB1

The toxicity evaluation suffers from the absence of suitable models capable of replicating in the co-cultured cell microenvironment and the function of specific tissues in vitro. Motivated by this urgent need, this study aimed to describe a novel three-dimensional (3D) liver spheroid model. The model consisted of a triple co-culture of HepG2, EA.hy 926, and LX-2. Subsequently, it was used for the toxicity evaluation of aflatoxin B1 (AFB1), and its advantages over the two-dimensional (2D) model and the mono-type cell spheroid model were assessed. This study examined the effects of AFB1 on cell viability, proliferation, mitochondria, oxidative stress, and cell membranes. The results revealed that AFB1 greatly affected 2D cell membranes and oxidative stress levels (0.01 μg/mL; 24 h), and could also significantly affect 2D cell viability, proliferation, and mitochondria levels (1 μg/mL; 24 h). On the contrary, 3D cells were less susceptible to AFB1. Combined with the analysis of gene expression, both metabolic activation (cytochrome P450; CYP450) and detoxification efficiency (drug-metabolizing enzymes) were found to be higher in 3D cells than in 2D cells. Moreover, 3D cells in triple co-culture outperformed mono-type cell spheroids. Therefore, the advanced 3D co-cultured spheroid model constructed in this study allowed us to more realistically simulate the microenvironment in vitro, and was a valuable and precise model to study mycotoxins.

Probiotic Bacillus Alleviates Oxidative Stress-Induced Liver Injury by Modulating Gut-Liver Axis in a Rat Model

Emerging evidence suggests a key role of gut microbiota in maintaining liver functions through modulating the gut–liver axis. In this study, we investigated whether microbiota alteration mediated by probiotic Bacillus was involved in alleviating oxidative stress- induced liver injury. Sprague–Dawley rats were orally administered Bacillus SC06 or SC08 for a 24-day period and thereafter intraperitoneally injected diquat (DQ) to induce oxidative stress. Results showed that Bacillus, particularly SC06 significantly inhibited hepatic injuries, as evidenced by the alleviated damaged liver structure, the decreased levels of ALT, AST, ALP and LDH, and the suppressed mitochondrial dysfunction. SC06 pretreatment markedly enhanced the liver antioxidant capacity by decreasing MDA and p47, and increasing T-AOC, SOD and HO-1.16S rRNA sequencing analysis revealed that DQ significantly changed the diversities and composition of gut microbiota, whereas Bacillus pretreatments could attenuate gut dysbiosis. Pearson’s correlation analysis showed that AST and MDA exerted a positive correlation with the opportunistic pathogenic genera and species (Escherichia and Shigella), and negatively correlated with the potential probiotics (Lactobacillus), while SOD exerted a reverse trend. The microbial metagenomic analysis demonstrated that Bacillus, particularly SC06 markedly suppress the metabolic pathways such as carbohydrate metabolism, lipid metabolism, amino acid metabolism and metabolism of cofactors and vitamins. Furthermore, SC06 decreased the gene abundance of the pathways mediating bacterial replication, secretion and pathogenicity. Taken together, Bacillus SC06 alleviates oxidative stress-induced liver injuries via optimizing the composition, metabolic pathways and pathogenic replication and secretion of gut microbiota. These findings elucidate the mechanisms of probiotics in alleviating oxidative stress and provide a promising strategy for preventing liver diseases by targeting gut microbiota.

Total flavonoids of Rhizoma Drynariae protect hepatocytes against aflatoxin B1-induced oxidative stress and apoptosis in broiler chickens

Aflatoxin B1 (AFB1) is a common mycotoxin in food and in the environment that lead to multi-organ injury in humans and animals. The objective of this study was to evaluate the detoxification properties of dietary total flavonoids of Rhizoma drynariae (TFRD), a Chinese herbal, on aflatoxin B1 (AFB1)-induced hepatic oxidative damage and apoptosis of liver of broiler chickens. A total of 160 healthy specific pathogen free (SPF) 21-day-old broilers were randomly allocated to 4 groups, including the CON group (basal diet), TFRD group (basal diet with 125 mg/kg TFRD), AFB1 group (100 μg/kg body weight), and AFB1 (100 μg/kg body weight) + TFRD (basal diet with 125 mg/kg TFRD) group. The exposure of AFB1 continued for seven days. The results showed that TFRD treatment alleviated the abnormal changes of growth performance and liver morphology, reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Moreover, TFRD promoted the antioxidant capacity of serum, increased the activities of total superoxide dismutase (T-SOD), oxidized glutathione (GSSG) and glutathione (GSH) (p < 0.05), while decreased MDA contents (p > 0.05). Meanwhile, supplementation of TFRD significantly increased the expression of antioxidant-related genes (SOD, CAT, GST, and GPX1) in liver (p < 0.05). Furthermore, we found that AFB1 was involved in the regulation of PI3K/AKT signaling pathway, leading to hepatocyte apoptosis. At the same time, TFRD treatment inhibited AFB1-induced apoptosis and significantly changed mRNA expression of apoptosis-related genes, including PI3K, AKT, Bax, and Bcl-2 (p < 0.05). The results indicated that TFRD could alleviate AFB1-induced liver injury in broiler chickens.

2-Amino-3-Methylimidazo[4,5-f]quinoline Triggering Liver Damage by Inhibiting Autophagy and Inducing Endoplasmic Reticulum Stress in Zebrafish (Danio rerio)

It is important to note that 2-Amino-3-methylimidazole[4,5-f]quinoline (IQ) is one of the most common heterocyclic amines (HCAs), which is a class of mutagenic/carcinogenic harmful compounds mainly found in high-protein thermal processed foods and contaminated environments. However, the pre-carcinogenic toxicity of IQ to the liver and its mechanism are poorly understood, further research is needed. In light of this, we exposed zebrafish to IQ (0, 8, 80, and 800 ng/mL) for 35 days, followed by comprehensive experimental studies. Histopathological and ultrastructural analysis showed that hepatocytes were damaged. TUNEL results showed that IQ induced apoptosis of liver cells, the expression of apoptosis factor gene was significantly increased, and the expression of Bcl-2 protein was significantly decreased. In addition, upregulated expression of the 78-kDa glucose-regulated protein (GRP78) and C/EBP homologous protein (CHOP) and endoplasmic reticulum stress (ERS)-related factors transcription levels were elevated obviously, suggesting that IQ induced ERS. Decreased protein expression of autophagy-related 5 (Atg5)-Atg12, Beclin1, and LC3-II, increased protein expression of p62, and autophagy-related factors transcription levels were significantly decreased, suggesting that IQ inhibited autophagy. Overall, our research showed that the potential harm of IQ to the liver before the occurrence of liver cancer was related to ERS and its mediated autophagy and apoptosis pathways.

Effect of Eriodictyol on Retinoblastoma via the PI3K/Akt Pathway

Retinoblastoma (RB) is one of the most common intraocular malignancies in children, which causes vision loss and even threatens life. Eriodictyol is a natural flavonoid with strong anticancer activity. Some studies have shown that eriodictyol exerts anticancer effects in glioma, colon cancer, and lung cancer; however, no studies have reported the anticancer effects of eriodictyol on RB. Therefore, the aim of this study was to investigate the anticancer activity of eriodictyol against the RB Y79 cell line and its potential mechanism of action. Interestingly, we found that eriodictyol inhibited the proliferation, migration, and invasion of Y79 cells in a dose-dependent manner and decreased the expression of MMP-2 and MMP-9 proteins in the cells. In addition, eriodictyol-induced apoptosis in Y79 cells was assessed by flow cytometry and immunoblotting. Here, our study revealed that eriodictyol dose dependently inhibited the activation of the PI3K/Akt signaling pathway. Notably, the effect of eriodictyol on RB apoptosis was reversed by a PI3K agonist 740 Y-P. In conclusion, our study shows that eriodictyol effectively inhibits proliferation, migration, and invasion and induces apoptosis in RB cell lines, which may be the result of blocking the PI3K/Akt signaling pathway. Thus, eriodictyol may provide a new theoretical basis for exploring targeted antitumor natural therapies.

Aflatoxin B1 interferes with embryonic liver development: Involvement of p53 signaling and apoptosis in zebrafish

Aflatoxin B₁ (AFB₁), a naturally occurring mycotoxin, is present in human placenta and cord blood. AFB₁ at concentrations found in contaminated food commodities (0.25 and 0.5 μM) did not alter the spontaneous movement, heart rate, hatchability, or morphology of embryonic zebrafish. However, around 86 % of 0.25 μM AFB₁-treated embryos had livers of reduced size, and AFB₁ disrupted the hepatocyte structures, according to histological analysis. Additionally, AFB₁ treatment that begins at any stage before 72 h post-fertilization (hpf) effectively reduced the size of embryonic livers. In hepatic areas, AFB₁ suppressed the expression of Hhex and Prox1, which are two critical transcriptional factors for initiating hepatoblast specification. KEGG analysis based on transcriptome profiling indicated that p53 signaling and apoptosis are the only observed pathways in AFB₁-treated embryos. AFB₁ at 0.5 μM significantly activated the expression of tp53, mdm2, puma, noxa, pidd1, and gadd45aa genes that are related to the p53 pathway and also that of baxa, casp 8 and casp 3a in the apoptotic process. TUNEL staining demonstrated that AFB₁ triggered the apoptosis of embryonic hepatocytes in a dose-dependent manner. These results indicate that the deficiency of both hhex and prox1 as well as hepatocyte apoptosis via the p53-Puma/Noxa-Bax axis may contribute to the embryonic liver shrinkage that is caused by AFB_1.

Selenium mitigated aflatoxin B1-induced cardiotoxicity with potential regulation of 4 selenoproteins and ferroptosis signaling in chicks

The aim of the present study was to explore the underlying mechanism of selenium (Se)-mediated detoxification of aflatoxin B₁ (AFB₁)-induced cardiotoxicity in chicks. A Se-deficient, corn-soybean meal-basal diet (36 μg Se/kg, BD) and three test diets (BD+1.0 mg AFB₁/kg, 0.3 mg Se/kg, or 1.0 mg AFB₁/kg+0.3 mg Se/kg) were used in a 3-wk 2 × 2 factorial design trial (n = 30 chicks/group). Dietary AFB₁ led to induced (P < 0.05) serum creatine kinase and creatine kinase MB isoenzyme activities and heart histopathologic lesions. However, Se deficiency aggravated most of these alterations induced by AFB₁. Moreover, mRNA levels of two ferroptosis activators (solute carrier family 11 Member 2 and transferrin) were upregulated (P < 0.05) in the AFB₁-treated groups. Additionally, Se deficiency reduced (P < 0.05) glutathione peroxidase (GPX) 3 and thioredoxin reductase 3 mRNA and GPX activity but increased (P < 0.05) selenoprotein M and selenophosphate synthetase 2 mRNA in the heart in AFB₁-administered groups. The in vitro study showed that Se alleviated (P < 0.05) AFB₁-reduced cell viability and induced (P < 0.05) ROS and ferroptosis in H9C2 cardiac cells. It also downregulated (P < 0.05) two ferroptosis activators (long-chain acyl-CoA synthetase 4 and solute carrier family 11 Member 2) in the AFB₁-treated groups in the H9C2 cells. In conclusion, this study illustrated that Se alleviates AFB₁-induced cardiotoxicity and cardiomyocyte damage potentially related to the regulation of redox status, 4 selenoproteins, and ferroptosis-related signaling.

Aflatoxins: History, Significant Milestones, Recent Data on Their Toxicity and Ways to Mitigation

In the early 1960s the discovery of aflatoxins began when a total of 100,000 turkey poults died by hitherto unknown turkey "X" disease in England. The disease was associated with Brazilian groundnut meal affected by Aspergillus flavus. The toxin was named Aspergillus flavus toxin-aflatoxin. From the point of view of agriculture, aflatoxins show the utmost importance. Until now, a total of 20 aflatoxins have been described, with B1, B2, G1, and G2 aflatoxins being the most significant. Contamination by aflatoxins is a global health problem. Aflatoxins pose acutely toxic, teratogenic, immunosuppressive, carcinogenic, and teratogenic effects. Besides food insecurity and human health, aflatoxins affect humanity at different levels, such as social, economical, and political. Great emphasis is placed on aflatoxin mitigation using biocontrol methods. Thus, this review is focused on aflatoxins in terms of historical development, the principal milestones of aflatoxin research, and recent data on their toxicity and different ways of mitigation.