Sodium Butyrate Protects the Intestinal Barrier by Modulating Intestinal Host Defense Peptide Expression and Gut Microbiota after a Challenge with Deoxynivalenol in Weaned Piglets

Intestinal microbiota-derived d-(+)-malic acid promotes pBD1 expression via p-p38/ATF1 signaling pathway to maintain porcine intestinal health

This study aims to identify nutrients that enhance the expression of host defense peptides (HDPs) and to evaluate their application effects and regulatory mechanisms, thereby advancing the exploring of nutritional regulation of HDPs. To achieve this, we constructed 16 stable fluorescent reporter porcine epithelial cell lines, driven by promoters targeting eight porcine intestinal HDPs genes, using IPEC-1 and IPEC-J2 cells. Through untargeted metabolomics sequencing and high-throughput screening, 15 metabolites were identified as potential enhancers of pBD1 expression, with d-(+)-malic acid (DMA) emerged as the most effective candidate. Transcriptomic and western blot analysis suggested that DMA enhances pBD1 expression primarily via the p-p38/ATF1 signaling pathways. Functional studies demonstrated that DMA significantly improved intestinal barrier integrity and alleviated intestinal damage. Overall, this work successfully established promoter-driven fluorescent reporter cell lines and identified microbiota-derived metabolites enhancing pBD1 expression, such as DMA, as promising alternatives to antibiotics for maintaining porcine intestinal health.

Protective effect of the branched short-chain fatty acid isobutyrate on intestinal damage in weaned piglets through intestinal microbiota remodeling

BACKGROUND

Postweaning intestinal damage in piglets is a challenging issue in the livestock industry. Short-chain fatty acids (SCFAs) are important metabolic products of the gut microbiota and are widely recognized for their role in maintaining normal colonic function and regulating the intestinal immune system. However, the effects of branched short-chain fatty acid (BSCFA) isobutyrate on intestinal health remain largely unknown. This study aims to explore the potential of isobutyrate for alleviating postweaning intestinal damage.

RESULTS

This study indicates that isobutyrate can alleviate diarrhea in weaned piglets, enhance their growth performance, and optimize the gut microbiota. This is mainly achieved through increasing the relative abundance of probiotic bacteria such as Lactobacillus, Megasphaera, and Prevotellaceae_UCG-003, while concurrently reducing the relative abundance of potentially harmful bacteria such as Clostridium_sensu_stricto-1 and Escherichia-Shigella. It promotes the production of SCFAs, including acetate, isobutyrate, and butyrate. Furthermore, it activates G-protein-coupled receptors (GPR43/109A), inhibits the TLR4/MyD88 signaling pathway, strengthens the intestinal barrier function, and regulates the expression of related cytokines.

CONCLUSION

In summary, exogenous isobutyrate can be considered a promising feed additive for improving the intestinal microbiota and regulating intestinal health in piglets. © 2024 Society of Chemical Industry.

Butyrate Supplementation Improves Intestinal Health and Growth Performance in Livestock: A Review

Butyrate supplementation has gained considerable attention for its potential benefits in livestock, particularly concerning intestinal health and growth performance. This review synthesizes recent research on the diverse roles of butyrate, across various livestock species. As a short-chain fatty acid, butyrate is known for enhancing intestinal development, improving immune function, and modulating microbial diversity. Studies indicate that butyrate supports gut barrier integrity, reduces inflammation, and optimizes feed efficiency, especially during the critical weaning and post-weaning periods in calves, piglets, and lambs. Supplementation with butyrate in livestock has been shown to increase average daily gain (ADG), improve gut microbiota balance, promote growth, enhance gut health, boost antioxidant capacity, and reduce diarrhea. Additionally, butyrate plays a role in the epigenetic regulation of gene expression through histone acetylation, influencing tissue development and immune modulation. Its anti-inflammatory and antioxidant effects have been demonstrated across various species, positioning butyrate as a potential therapeutic agent in animal nutrition. This review suggests that optimizing butyrate supplementation strategies to meet the specific needs of each species may yield additional benefits, establishing butyrate as an important dietary additive for enhancing growth performance and health in livestock.

Butyrate: A potential mediator of obesity and microbiome via different mechanisms of actions

Butyrate, a short-chain fatty acid, is a crucial product of gut microbial fermentation with significant implications for various metabolic and physiological processes. Dietary sources of butyrate are limited, primarily derived from the fermentation of dietary fibers by butyrate-producing gut bacteria. Butyrate exerts its effects primarily as a histone deacetylase (HDAC) inhibitor and through signaling pathways involving G protein-coupled receptors (GPCRs). Its diverse benefits include promoting gut health, enhancing energy metabolism, and potentially alleviating complications associated with obesity. However, the exact role of butyrate in obesity is still under investigation, with a limited number of human trials necessitating further research to determine its efficacy and safety profile. Moreover, butyrate impact on the gut-brain axis and its modulation of microbiome effect on behavior highlight its broader importance in regulating host physiology. A thorough understanding of the metabolic pathways and mechanisms of butyrate is essential for developing targeted interventions for metabolic disorders. Continued research is crucial to fully realize its therapeutic potential and optimize its clinical applications in human health. In summary, this review illuminates the multifaceted role of butyrate as a potential mediator of obesity and related metabolic changes.

Effect of iron-manganese oxide on the degradation of deoxynivalenol in feed and enhancement of growth performance and intestinal health in weaned piglets

Deoxynivalenol (DON), a prevalent and highly toxic mycotoxin in animal feed, poses significant risks to livestock health and productivity. This study evaluates the effectiveness of iron-manganese oxide (Fe/Mn oxides) in degrading DON. The DON degradation rate of Fe/Mn oxide reached 98.46 % in a controlled solution under specific conditions (0.2 % concentration, 37-85 °C, pH 6-7, 1-minute reaction time). When applied to actual feed, it reduced DON levels by approximately 49.3 % and remained stable in simulated gastrointestinal environments of weaned piglets. A 28-day trial involving 48 weaned piglets assessed the impacts of Fe/Mn oxides on health and growth. Results indicated that piglets consuming contaminated feed without the treatment exhibited reduced growth and compromised gut integrity, which were significantly mitigated by the addition of Fe/Mn oxides. Therefore, Fe/Mn oxides effectively reduce DON in feed and alleviate adverse health effects in piglets, making them a viable option to enhance safety and performance in mycotoxin-prone environments.

Chronic dietary deoxynivalenol exposure interferes the intestinal microbial community structure and antibiotic resistome in laying hens

Antibiotic resistance genes (ARGs) are critical emerging pollutants that have attracted considerable attention. Deoxynivalenol (DON) is one of the most prevalent mycotoxins in cereal crops worldwide, arising severe health hazards to both humans and animals. Even if numerous researches argue in favor of a notorious influence of DON on the gut, the effects of dietary DON exposure on the ARG profile in poultry intestine remain obscure. In this study, two separate feeding experiments using Jing Tint 6 laying hens exposed to 4.5 or 9.0 mg/kg DON were performed to explore the impact of dietary DON exposure on the microbial community structure and the profiles of ARGs in the intestine via 16S rDNA sequencing and metagenomics sequencing, respectively. In addition, growth performance and intestinal barrier function were also determined to assess the feasibility of using DON-contaminated feedstuffs inappropriate for pigs' consumption in laying hens. Chronic ingestion of DON at 9.0 mg/kg did not alter zootechnical parameters. However, histomorphological impairments were observed in liver and jejunum. Additionally, metagenomic sequencing revealed that dietary DON exposure at 9.0 mg/kg level dramatically changed the gut microbial structure and shifted the ARG profile. The abundance of tetracycline ARG subtype in the layer cecum was decreased, whereas the abundance of vancomycin ARG subtype was increased upon DON exposure. Co-occurrence network analysis identified that Prevotella was the major ARG host in the intestine of laying hens. In summary, our findings demonstrated that DON-contaminated feedstuffs inappropriate for pigs' consumption should be prudently used in hen production, and shed new light on the interactions between mycotoxins and ARGs in the poultry intestine.

Branched Short-Chain Fatty Acid-Rich Fermented Protein Food Improves the Growth and Intestinal Health by Regulating Gut Microbiota and Metabolites in Young Pigs

The diet in early life is essential for the growth and intestinal health later in life. However, beneficial effects of a diet enriched in branched short-chain fatty acids (BSCFAs) for infants are ambiguous. This study aimed to develop a novel fermented protein food, enriched with BSCFAs and assess the effects of dry and wet ferment products on young pig development, nutrient absorption, intestinal barrier function, and gut microbiota and metabolites. A total of 18 young pigs were randomly assigned to three groups. The dry corn gluten-wheat bran mixture (DFCGW) and wet corn gluten-wheat bran mixture (WFCGW) were utilized as replacements for 10% soybean meal in the basal diet. Our results exhibited that the WFCGW diet significantly increased the growth performance of young pigs, enhanced the expression of tight junction proteins, and regulated associated cytokines expression in the colonic mucosa. Simultaneously, the WFCGW diet led to elevated levels of colonic isobutyric and isovaleric acid, as well as the activation of GPR41 and GPR109A. Furthermore, more potential probiotics including Lactobacillus, Megasphaera, and Lachnospiraceae_ND3007_group were enriched in the WFCGW group and positively associated with the beneficial metabolites such as 5-hydroxyindole-3-acetic acid. Differential metabolite KEGG pathway analysis suggested that WFCGW might exert gut health benefits by modulating tryptophan metabolism. In addition, the WFCGW diet significantly increased ghrelin concentrations in serum and hypothalamus and promoted the appetite of young pigs by activating hypothalamic NPY/AGRP neurons. This study extends the knowledge of BSCFAs and provides a reference for the fermented food application in the infant diet.

Nutritional Modulation of Host Defense Peptide Synthesis: A Novel Host-Directed Antimicrobial Therapeutic Strategy?

The escalating threat of antimicrobial resistance underscores the imperative for innovative therapeutic strategies. Host defense peptides (HDPs), integral components of innate immunity, exhibit profound antimicrobial and immunomodulatory properties. Various dietary compounds, such as short-chain fatty acids, vitamins, minerals, sugars, amino acids, phytochemicals, bile acids, probiotics, and prebiotics have been identified to enhance the synthesis of endogenous HDPs without provoking inflammatory response or compromising barrier integrity. Additionally, different classes of these compounds synergize in augmenting HDP synthesis and disease resistance. Moreover, dietary supplementation of several HDP-inducing compounds or their combinations have demonstrated robust protection in rodents, rabbits, pigs, cattle, and chickens from experimental infections. However, the efficacy of these compounds in inducing HDP synthesis varies considerably among distinct compounds. Additionally, the regulation of HDP genes occurs in a gene-specific, cell type-specific, and species-specific manner. In this comprehensive review, we systematically summarized the modulation of HDP synthesis and the mechanism of action attributed to each major class of dietary compounds, including their synergistic combinations, across a spectrum of animal species including humans. We argue that the ability to enhance innate immunity and barrier function without triggering inflammation or microbial resistance positions the nutritional modulation of endogenous HDP synthesis as a promising host-directed approach for mitigating infectious diseases and antimicrobial resistance. These HDP-inducing compounds, particularly in combinations, harbor substantial clinical potential for further exploration in antimicrobial therapies for both human and other animals.

Necroptosis contributes to the intestinal toxicity of deoxynivalenol and is mediated by methyltransferase SETDB1

Deoxynivalenol (DON) is a secondary metabolite produced by fungi, which causes serious health issues worldwide due to its widespread presence in human and animal diets. Necroptosis is a newly proposed cell death mode and has been proposed as a potential mechanism of intestinal disease. This study aimed to investigate the role of necroptosis in intestinal damage caused by DON exposure. Piglets were fed diets with or without 4 mg/kg DON for 3 weeks or given a gavage of 2 mg/kg BW DON or sterile saline to investigate the effects of chronic or acute DON exposure on the gut, respectively. IPEC-1 cells were challenged with different concentrations of DON to investigate the effect of DON exposure on the intestinal epithelial cells (IECs) in vitro. Subsequently, the inhibitors of necroptosis were used to treat cells or piglets prior to DON challenge. Chronic and acute DON exposure both caused morphological damage, reduction of disaccharidase activity, decrease of tight junction protein expression, inflammation of the small intestine, and necroptosis of intestinal epithelial cells in piglets. Necroptosis was also detected when IPEC-1 cell damage was induced by DON in vitro. The suppression of necroptosis in IPEC-1 cells by inhibitors (necrostatin-1 (Nec-1), GSK'872, or GW806742X) alleviated cell death, the decrease of tight junction protein expression, oxidative stress, and the inflammatory response induced by DON. Furthermore, pre-treatment with Nec-1 in piglets was also observed to protect the intestine against DON-induced enterotoxicity. Additionally, the expression of histone methyltransferase SETDB1 was abnormally downregulated upon chronic and acute DON exposure in piglets, and necroptosis was activated in IPEC-1 cells due to knockout of SETDB1. Collectively, these results demonstrate that necroptosis of IECs is a mechanism of DON-induced enterotoxicity and SETDB1 mediates necroptosis upon DON exposure in IECs, suggesting the potential for targeted inhibition of necroptosis to alleviate mycotoxin-induced enterotoxicity and intestinal disease.

Supplementation of coated sodium butyrate relieved weaning stress and reshaped microbial flora in weaned lambs

Weaning is an important period in the growth and development of lambs. Thus, effectively reducing the occurrence of weaning stress is critical for maintaining lamb production. Coated sodium butyrate has been shown to reduce inflammation, promote intestinal health, and maintain homeostasis. However, the application and potential mechanism of coated sodium butyrate in alleviating weaning stress in lambs are still unclear. To evaluate the effects of coated sodium butyrate on the growth performance, antioxidant capacity, and gut microbiota of weaned lambs, 10 weaned lambs of 21-day-old were randomly divided into two groups: the CON group (basal diet) and the NaB group (basal diet +3 g/kg of coated sodium butyrate). The trial lasted 21 days. The experimental results showed that compared to the CON group, coated sodium butyrate supplementation in the diet significantly increased the average daily weight gain and daily feed intake of lambs (p < 0.05). In addition, compared to the CON group, the addition of coated sodium butyrate also significantly decreased the serum MDA level of lambs (p < 0.05). Notably, the addition of coated sodium butyrate did not have a significant effect on the cecal microbiota, while increasing the diversity of colonic microbiota and promoting the abundance of Lachnospiraceae, Verrucomicrobiota, Akkermansia, Roseburia, and Sinobacteraceae, which are associated with the nutrient absorption of lambs (p < 0.05). These results indicate that dietary supplementation with coated sodium butyrate could promote the growth and antioxidant capacity of weaned lambs and alleviate weaning stress.

Agaro-oligosaccharides mitigate deoxynivalenol-induced intestinal inflammation by regulating gut microbiota and enhancing intestinal barrier function in mice

Agarose-derived agaro-oligosaccharides (AgaroS) have been extensively studied in terms of structures and bioactivities; they reportedly possess antioxidant and anti-inflammatory activities that maintain intestinal homeostasis and host health. However, the protective effects of AgaroS on deoxynivalenol (DON)-induced intestinal dysfunction remain unclear. We investigated the effects of AgaroS on DON-induced intestinal dysfunction in mice and explored the underlying protective mechanisms. In total, 32 mice were randomly allocated to four treatments (n = 8 each) for 28 days. From day 1 to day 21, the control (CON) and DON groups received oral phosphate-buffered saline (200 μL per day); the AgaroS and AgaroS + DON groups received 200 mg AgaroS per kg body weight once daily by orogastric gavage. Experimental intestinal injury was induced by adding DON (4.8 mg per kg body weight) via gavage from day 21 to day 28. Phosphate-buffered saline was administered once daily by gavage in the CON and AgaroS groups. Herein, AgaroS supplementation led to a higher final body weight and smaller body weight loss and a lower concentration of plasma inflammatory cytokines, compared with the DON group. The DON group showed a significantly reduced ileal villus height and villus height/crypt depth, compared with the CON and AgaroS + DON groups. However, AgaroS supplementation improved DON-induced intestinal injury in mice. Compared with the DON group, ileal and colonic protein expression levels of claudin, occludin, Ki67, and mucin2 were significantly higher in the AgaroS supplementation group. Colonic levels of the anti-inflammatory cytokine IL-1β tended to be higher in the DON group than in the AgaroS + DON group. AgaroS altered the gut microbiota composition, accompanied by increased production of short-chain fatty acids in mice. In conclusion, our findings highlight a promising anti-mycotoxin approach whereby AgaroS alleviate DON-induced intestinal inflammation by modulating intestinal barrier functional integrity and gut microbiota in mice.

Gut microbiota-derived short-chain fatty acids and depression: deep insight into biological mechanisms and potential applications

The gut microbiota is a complex and dynamic ecosystem known as the 'second brain'. Composing the microbiota-gut-brain axis, the gut microbiota and its metabolites regulate the central nervous system through neural, endocrine and immune pathways to ensure the normal functioning of the organism, tuning individuals' health and disease status. Short-chain fatty acids (SCFAs), the main bioactive metabolites of the gut microbiota, are involved in several neuropsychiatric disorders, including depression. SCFAs have essential effects on each component of the microbiota-gut-brain axis in depression. In the present review, the roles of major SCFAs (acetate, propionate and butyrate) in the pathophysiology of depression are summarised with respect to chronic cerebral hypoperfusion, neuroinflammation, host epigenome and neuroendocrine alterations. Concluding remarks on the biological mechanisms related to gut microbiota will hopefully address the clinical value of microbiota-related treatments for depression.

Multi-omics reveals the protective effects of curcumin against AFB1-induced oxidative stress and inflammatory damage in duckling intestines

Aflatoxin B1 (AFB1) is the most prevalent and toxic class of aflatoxins, which is considered a significant risk factor for food safety. Curcumin, a phytoconstituent with anti-inflammatory and antioxidant properties, has potential therapeutic value for intestinal inflammatory diseases. In this study, the duckling model susceptible to AFB1 was selected for toxicity testing, aiming to explore the effect of curcumin on AFB1 enterotoxicity and its possible mechanism of action. The results showed that curcumin promoted the growth and development of ducklings and mitigated the changes in morphology and permeability serological index (DAO and D-LA) after AFB1 exposure. Curcumin also mitigated AFB1-induced oxidative stress by activating the Nrf2 pathway, and ameliorated intestinal inflammation by inhibiting the NF-κB/IκB signaling pathway and boosting intestinal autophagy. In terms of gut flora and their metabolites, we found that curcumin supplementation significantly increased the intestinal flora's abundance index and diversity index compared to the AFB1 group, mitigating the decline in the abundance of Actinobacteria and the rise in that of harmful bacteria Clostridia. Furthermore, untargeted metabolomic analysis revealed that the protective effect of curcumin on the intestine was mainly through the regulation of AFB1-induced disorders of lipid metabolism, involving linoleic acid metabolism, α-linolenic acid metabolism, and glycerolipid metabolism. Overall, the enteroprotective effects of curcumin may be of significant value in the future for treating chronic AFB1 poisoning and also provide new therapeutic ideas for other mycotoxicosis.

Butyrate reduces epithelial barrier dysfunction induced by the foodborne mycotoxin deoxynivalenol in cell monolayers derived from pig jejunum organoids

The foodborne mycotoxin deoxynivalenol (DON) produced by Fusarium species threats animal and human health through disruption of the intestinal barrier. Targeting the gut microbiota and its products appears as a promising strategy to mitigate DON intestinal toxicity. In this study, we investigated whether the bacterial metabolite butyrate could alleviate epithelial barrier disruption induced by DON. We used a model of cell monolayers derived from porcine jejunum organoids allowing to reproduce the cellular complexity of the intestinal epithelium. Our results show that DON dose-dependently disrupted the epithelial barrier integrity, reduced epithelial differentiation, and altered innate immune defenses. Butyrate attenuated the DON-induced increase in paracellular permeability. Butyrate also prevented epithelial barrier dysfunction triggered by anisomycin, a ribosome inhibitor like DON. Moreover, butyrate partially counteracted the effects of DON on tight junctions (TJP1, OCLN), innate epithelial defenses (PTGS2, CD14, TLR4, TLR5), and absorptive cell functions (CA2, VIL1, NHE3, CFTR). In contrast, butyrate did not prevent the toxic effects of DON on mitochondrial metabolism, proliferation and goblet cell functions. Taken together, our results demonstrate that the bacterial metabolite butyrate is able to reduce DON-induced epithelial barrier disruption.

Caffeic acid improves intestinal barrier functions by regulating colonic bacteria and tight junction protein expression and alleviating inflammation in weaning piglets

The experiment investigated the effect of caffeic acid on bacteria, short-chain fatty acids (SCFA), and the expression of tight junction protein and inflammation related genes in the colon of weaning piglets. Thirty-six weaning piglets were allocated to three treatment groups, which were fed with a basal diet, a basal diet supplemented with 250 mg/kg or 500 mg/kg caffeic acid for 28 days. The results showed that caffeic acid treatment increased the contents of acetate acid, propionate acid and total SCFA. Moreover, real-time quantitative PCR showed that the number of Bifidobacterium (p < 0.05) and Lactobacillus (p < 0.05) were increased and the number of Escherichia coli (p < 0.05) was decreased by caffeic acid in colonic mucosa. Real-time quantitative PCR also showed that the mRNA levels of zonula occludens-1 (p < 0.01), claudin-1 (p < 0.01), occludin (p < 0.01), mucin 1 (MUC1) (p < 0.01), MUC2 (p < 0.01), interleukin 4 (IL-4) (p < 0.01) and IL-10 (p < 0.05) were increased, while the mRNA expression levels of histone deacetylases (p < 0.01), IL-1 (p < 0.01), IL-6 (p < 0.01) and tumor necrosis factor-α (TNF-α) (p < 0.01) were decreased, by caffeic acid in colonic mucosa. These results suggested that caffeic acid could improve intestinal barrier function in weaned pigs, which might be mediated by regulating colonic bacteria and tight junction protein expression and alleviating inflammation.

Effect of deoxynivalenol on inflammatory injury on the glandular stomach in chick embryos

Deoxynivalenol (DON) has a strong toxic effect on the gastrointestinal mucosa of poultry. In this study, we evaluated chicken embryo development and glandular stomach damage to clarify the immunotoxic effects of DON injected through the allantoic cavity of chicken embryos. The glandular stomach index, routine blood indices, plasma inflammatory factors, pathological changes in the glandular stomach, and transcriptome results were analyzed in the hatching chicks. The results showed that DON was supertoxic to chicken embryos, causing edema, shedding, and bleeding of the mucosa of the glandular stomach, which triggered inflammatory reactions. As the toxin concentration increased, the immune system was successively activated and inhibited, and regulation was carried out by the differential regulation of the mitogen-activated protein kinase (MAPK) signal pathway. These results suggested that the immunotoxic effect of DON on the glandular stomach of chicken embryos was closely related to the regulation of the MAPK signaling pathway.

Sodium butyrate alleviates deoxynivalenol-induced porcine intestinal barrier disruption by promoting mitochondrial homeostasis via PCK2 signaling

Deoxynivalenol (DON) is one of the most plentiful trichothecenes occurring in food and feed, which brings severe health hazards to both animals and humans. This study aims to investigate whether sodium butyrate (NaB) can protect the porcine intestinal barrier from DON exposure through promoting mitochondrial homeostasis. In a 4-week feeding experiment, 28 male piglets were allocated according to a 2 by 2 factorial arrangement of treatments with the main factors including supplementation of DON (< 0.8 vs. 4.0 mg/kg) and NaB (0.0 vs. 2 g/kg) in a corn/soybean-based diet. Dietary NaB supplementation mitigated the damaged mitochondrial morphology within the jejunal mucosa and the disrupted gut epithelial tight junctions irritated by DON. In IPEC-J2 cells, we found efficient recovery of the intestinal epithelial barrier occurred following NaB administration. This intestinal barrier reparation was facilitated by NaB-induced PCK2-mediated glyceroneogenesis and restoration of mitochondrial structure and function. In conclusion, we elucidated a mechanism of PCK2-mediated improvement of mitochondrial function by NaB to repair porcine intestinal barrier disruption during chronic DON exposure. Our findings highlight the promise of NaB for use in protecting against DON-induced gut epithelial tight junction disruption in piglets.

Maternal Supplementation of Vitamin E or Its Combination with Hydroxytyrosol Increases the Gut Health and Short Chain Fatty Acids of Piglets at Weaning

An adequate intestinal environment before weaning may contribute to diarrhea predisposition and piglet development. This study evaluates how the dietary supplementation of vitamin E (VE) (100 mg/kg), hydroxytyrosol (HXT) (1.5 mg/kg) or the combined administration (VE + HXT) given to Iberian sows from gestation affects the piglet's faecal characteristics, short chain fatty acids (SCFAs), fatty acid profile or intestinal morphology as indicators of gut health; and quantify the contribution of the oxidative status and colostrum/milk composition to the piglet's SCFAs content and intestinal health. Dietary VE increased isobutyric acid (iC4), butyric acid (C4), isovaleric acid (iC5), and ∑SCFAs, whereas HXT increased iC4 and tended to decrease ∑SCFAs of faeces. Piglets from HXT-supplemented sows also tended to have higher faecal C20:4n-6/C20:2 ratio C22:6 proportion and showed lower occludin gene expression in the duodenum. The combination of both antioxidants had a positive effect on iC4 and iC5 levels. Correlation analyses and regression equations indicate that faecal SCFAs were related to oxidative status (mainly plasma VE) and colostrum and milk composition (mainly C20:2, C20:3, C20:4 n-6). This study would confirm the superiority of VE over HXT supplementation to improve intestinal homeostasis, gut health, and, consequently piglet growth.

Quercetin attenuates deoxynivalenol-induced intestinal barrier dysfunction by activation of Nrf2 signaling pathway in IPEC-J2 cells and weaned piglets

The presence of deoxynivalenol (DON), one of the most frequently occurring mycotoxin, in food and feed has been considered a risk factor to both human and animal health. Molecular mechanisms that regulate DON effects in tissues are still poorly understood. However, recent evidence suggests that nuclear factor erythroid 2-like 2 (Nrf2) may be a major target during mycotoxin-induced intestinal barrier dysfunction. Although quercetin, a plant-derived flavonoid, is known to induce the activation of Nrf2 signaling pathway, its potential to mitigate effects of DON and the implication of Nrf2 in its physiological effects is poorly understood. Therefore, this study was conducted to investigate the protective effects of quercetin in alleviating the DON-induced barrier loss and intestinal injuries in IPEC-J2 cells and weaned piglets and determine the potential role of Nrf2. Quercetin treatment dose-dependently increased mRNA expression of Nrf2 target gene, NQO-1, and concomitantly increased the expression of claudin-4 at both mRNA and protein levels. Quercetin supplementation also reversed the reduction of claudin-4 caused by DON exposure in vivo and in vitro. The decreased membrane presence of claudin-4 and ZO-1 induced by DON was also blocked by quercetin. Furthermore, quercetin attenuated the endocytosis and degradation of claudin-4 caused by DON exposure. The effects of quercetin also included the restoration of transepithelial electrical resistance (TEER) and reduction of FITC-dextran permeability that have been perturbed by DON. However, the protective effects of quercetin against DON exposure were abolished by a specific Nrf2 inhibitor (brusatol), confirming the importance of Nrf2 in the regulation of TJP expression and barrier function by quercetin. In vivo study in weaned pigs showed that DON exposure impaired villus-crypt morphology as indicated by diffuse apical villus necrosis, villus atrophy and fusion. Notably, intestinal injuries caused by DON administration were partly mitigated by quercetin supplementation. Collectively, this study shows that quercetin could be used to prevent the DON-induced gut barrier dysfunction in humans and animals and the protective effects of quercetin against DON-induced intestinal barrier disruption is partly through Nrf2-dependent signaling pathway.

Sodium Butyrate Ameliorates Deoxynivalenol-Induced Oxidative Stress and Inflammation in the Porcine Liver via NR4A2-Mediated Histone Acetylation

Mycotoxin-induced liver injury is often accompanied by oxidative stress (OS) and inflammation. This research aimed to explore the potential mechanism of sodium butyrate (NaBu) in modulating hepatic anti-oxidation and anti-inflammation pathways in deoxynivalenol (DON)-exposed piglets. The results show that DON induced liver injury, increased mononuclear cell infiltration, and decreased serum total protein and albumin concentrations. Transcriptomic analysis revealed that reactive oxygen species (ROS) and TNF-α pathways were highly activated upon DON exposure. This is associated with disturbed antioxidant enzymes and increased inflammatory cytokines secretion. Importantly, NaBu effectively reversed the alterations caused by DON. Mechanistically, the ChIP-seq result revealed that NaBu strongly depressed DON-increased enrichment of histone mark H3K27ac at the genes involved in ROS and TNF-α-mediated pathways. Notably, we demonstrated that nuclear receptor NR4A2 was activated by DON and remarkably recovered with the treatment of NaBu. In addition, the enhanced NR4A2 transcriptional binding enrichments at the promoter regions of OS and inflammatory genes were hindered by NaBu in DON-exposed livers. Consistently, elevated H3K9ac and H3K27ac occupancies were also observed at the NR4A2 binding regions. Taken together, our results indicated that a natural antimycotic additive, NaBu, could mitigate hepatic OS and inflammatory responses, possibly via NR4A2-mediated histone acetylation.

Microbiota-derived short-chain fatty acids and modulation of host-derived peptides formation: Focused on host defense peptides

The byproducts of bacterial fermentation known as short-chain fatty acids (SCFAs) are chemically comprised of a carboxylic acid component and a short hydrocarbon chain. Recent investigations have demonstrated that SCFAs can affect intestinal immunity by inducing endogenous host defense peptides (HDPs) and their beneficial effects on barrier integrity, gut health, energy supply, and inflammation. HDPs, which include defensins, cathelicidins, and C-type lectins, perform a significant function in innate immunity in gastrointestinal mucosal membranes. SCFAs have been demonstrated to stimulate HDP synthesis by intestinal epithelial cells via interactions with G protein-coupled receptor 43 (GPR43), activation of the Jun N-terminal kinase (JNK) and Mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathways, and the cell growth pathways. Furthermore, SCFA butyrate has been demonstrated to enhance the number of HDPs released from macrophages. SCFAs promote monocyte-to-macrophage development and stimulate HDP synthesis in macrophages by inhibiting histone deacetylase (HDAC). Understanding the etiology of many common disorders might be facilitated by studies into the function of microbial metabolites, such as SCFAs, in the molecular regulatory processes of immune responses (e.g., HDP production). This review will focus on the current knowledge of the role and mechanism of microbiota-derived SCFAs in influencing the synthesis of host-derived peptides, particularly HDPs.

Combination of glycyrrhizic acid and compound probiotics alleviates deoxynivalenol-induced damage to weaned piglets

Deoxynivalenol (DON) can affect health and growth performance of pigs, resulting in significant economic losses in swine production. The aim of this study was to investigate the effect of glycyrrhizic acid combined with compound probiotics, i.e. Enterococcus faecalis plus Saccharomyces cerevisiae (GAP) on improving growth performance, intestinal health and its fecal microbiota composition change of piglets challenged with DON. A total of 160 42-day-old weaned piglets (Landrace × Large White) were used and the experimental period was 28 d. The results showed that supplementing GAP in the diet significantly improved the growth performance of piglets challenged with DON and alleviate DON-induced intestinal damage by reducing ALT, AST and LDH concentrations in serum, increasing the morphological parameters of jejunum, and decreasing DON residues in serum, liver and feces. Moreover, GAP could significantly decrease the expressions of inflammation and apoptosis genes and proteins (IL-8, IL-10, TNF-α, COX-2, Bax, Bcl-2 and Caspase 3), and increase the expressions of tight-junction proteins and nutrient transport factor genes and proteins (ZO-1, Occludin, Claudin-1, ASCT2 and PePT1). In addition, it was also found that GAP supplementation could significantly increase the diversity of gut microbiota, maintain microbial flora balance and promote piglet growth by significantly increasing the abundance of beneficial bacterium such as Lactobacillus and reducing the abundance of harmful bacterium such as Clostridium_sensu_stricto_1. In conclusion, GAP addition to piglet diets contaminated with DON could significantly promote the health and growth performance of piglets though alleviating DON-induced hazards. This study provided a theoretical basis for the application of GAP to alleviate DON toxicity for animals.

Deoxynivalenol induces intestinal injury: insights from oxidative stress and intestinal stem cells

Mycotoxins are fungal secondary metabolites that frequently occur in human and animal diets. Deoxynivalenol (DON) is one of the most widely occurring mycotoxins globally and poses significant harm to the animal husbandry industry and human health. People are increasingly aware of the adverse effects of DON on vulnerable structures and functions in the intestine, especially in the field of intestinal stem cells (ISCs). In this review, we present insights into DON that induces oxidative stress and affects the expansion of ISCs. Related studies of strategies for reducing its harm are summarized. We also discussed promising approaches such as regulation of microbiota, molecular docking, and modulation of the redox status via reducing the expression of Keap1 protein and single-cell sequencing, which may be critical for further revealing the mechanism of DON that induces oxidative stress and affects the expansion of ISCs.

Clostridium butyricum Prevents Dysbiosis and the Rise in Blood Pressure in Spontaneously Hypertensive Rats

Hypertension is accompanied by dysbiosis and a decrease in the relative abundance of short-chain fatty acid (SCFA)-producing bacteria. However, there is no report to examine the role of C. butyricum in blood pressure regulation. We hypothesized that a decrease in the relative abundance of SCFA-producing bacteria in the gut was the cause of spontaneously hypertensive rats (SHR)-induced hypertension. C. butyricum and captopril were used to treat adult SHR for six weeks. C. butyricum modulated SHR-induced dysbiosis and significantly reduced systolic blood pressure (SBP) in SHR (p < 0.01). A 16S rRNA analysis determined changes in the relative abundance of the mainly SCFA-producing bacteria Akkermansia muciniphila, Lactobacillus amylovorus, and Agthobacter rectalis, which increased significantly. Total SCFAs, and particularly butyrate concentrations, in the SHR cecum and plasma were reduced (p < 0.05), while C. butyricum prevented this effect. Likewise, we supplemented SHR with butyrate for six weeks. We analyzed the flora composition, cecum SCFA concentration, and inflammatory response. The results showed that butyrate prevented SHR-induced hypertension and inflammation, and the decline of cecum SCFA concentrations (p < 0.05). This research revealed that increasing cecum butyrate concentrations by probiotics, or direct butyrate supplementation, prevented the adverse effects of SHR on intestinal flora, vascular, and blood pressure.

Host Defense Peptides in Nutrition and Diseases: A Contributor of Immunology Modulation

Host defense peptides (HDPs) are primary components of the innate immune system with diverse biological functions, such as antibacterial ability and immunomodulatory function. HDPs are produced and released by immune and epithelial cells against microbial invasion, which are widely distributed in humans, animals, plants, and microbes. Notably, there are great differences in endogenous HDP distribution and expression in humans and animals. Moreover, HDP expression could be regulated by exogenous substances, such as nutrients, and different physiological statuses in health and disease. In this review, we systematically assessed the regulation of expression and mechanism of endogenous HDPs from nutrition and disease perspectives, providing a basis to identify the specificity and regularity of HDP expression. Furthermore, the regulation mechanism of HDP expression was summarized systematically, and the differences in the regulation between nutrients and diseases were explored. From this review, we provide novel ideas targeted the immune regulation of HDPs for protecting host health in nutrition and practical and effective new ideas using the immune regulation theory for further research on protecting host health from pathogenic infection and excessive immunity diseases under the global challenge of the antibiotic-abuse-induced series of problems, including food security and microbial resistance.

Sodium butyrate alleviates deoxynivalenol-induced hepatic cholesterol metabolic dysfunction via RORγ-mediated histone acetylation modification in weaning piglets

BACKGROUND

Cholesterol is an essential component of lipid rafts in cell plasma membrane, which exerts a hepatoprotective role against mycotoxin exposure in pigs, and cholesterol metabolism is vulnerable to epigenetic histone acetylation. Therefore, our present study aimed to investigate whether a histone deacetylase inhibitor (sodium butyrate [NaBu]) could protect the porcine liver from deoxynivalenol (DON) exposure by modulating cholesterol metabolism. Herein, we randomly divided 28 pigs into four groups, which were fed an uncontaminated basal diet, contaminated diet (4 mg DON/kg), uncontaminated diet supplemented with 0.2% NaBu or 4 mg/kg DON contaminated diet (4 mg DON/kg) supplemented with 0.2% NaBu for 28 d.

RESULTS

We found that the serum alanine transaminase (ALT), aspartate transaminase (AST), and alkaline phosphatase (ALP) were all increased in pigs exposed to DON, indicative of significant liver injury. Furthermore, the cholesterol content in the serum of DON-exposed pigs was significantly reduced, compared to the healthy Vehicle group. Transcriptome analysis of porcine liver tissues revealed that the cholesterol homeostasis pathway was highly enriched due to DON exposure. In which we validated by qRT-PCR and western blotting that the cholesterol program was markedly activated. Importantly, NaBu effectively restored parameters associated with liver injury, along with the cholesterol content and the expression of key genes involved in the cholesterol biosynthesis pathway. Mechanistically, we performed a ChIP-seq analysis of H3K27ac and showed that NaBu strongly diminished DON-increased H3K27ac genome-wide enrichment. We further validated that the elevated H3K27ac and H3K9ac occupancies on cholesterol biosynthesis genes were both decreased by NaBu, as determined by ChIP-qPCR analysis. Notably, nuclear receptor RORγ, a novel regulator of cholesterol biosynthesis, was found in the hyperacetylated regions. Again, a remarkable increase of RORγ at both mRNA and protein levels in DON-exposed porcine livers was drastically reduced by NaBu. Consistent with RORγ expression, NaBu also hindered RORγ transcriptional binding enrichments on these activated cholesterol biosynthesis genes like HMGCR, SQLE, and DHCR24. Furthermore, we conducted an in vitro luciferase reporter assay to verify that porcine RORγ directly bonds to the promoters of the above target genes.

CONCLUSIONS

Collectively, our results demonstrate the utility of the natural product NaBu as a potential anti-mycotoxin nutritional strategy for regulating cholesterol metabolism via RORγ-mediated histone acetylation modification.

Crosstalk between Mycotoxins and Intestinal Microbiota and the Alleviation Approach via Microorganisms

Mycotoxins are secondary metabolites produced by fungus. Due to their widespread distribution, difficulty in removal, and complicated subsequent harmful by-products, mycotoxins pose a threat to the health of humans and animals worldwide. Increasing studies in recent years have highlighted the impact of mycotoxins on the gut microbiota. Numerous researchers have sought to illustrate novel toxicological mechanisms of mycotoxins by examining alterations in the gut microbiota caused by mycotoxins. However, few efficient techniques have been found to ameliorate the toxicity of mycotoxins via microbial pathways in terms of animal husbandry, human health management, and the prognosis of mycotoxin poisoning. This review seeks to examine the crosstalk between five typical mycotoxins and gut microbes, summarize the functions of mycotoxins-induced alterations in gut microbes in toxicological processes and investigate the application prospects of microbes in mycotoxins prevention and therapy from a variety of perspectives. The work is intended to provide support for future research on the interaction between mycotoxins and gut microbes, and to advance the technology for preventing and controlling mycotoxins.

Lactobacillus plantarum and Deoxynivalenol Detoxification: A Concise Review

ABSTRACT

Mycotoxins are toxic secondary fungal metabolites that contaminate feeds, and their levels remain stable during feed processing. The economic impact of mycotoxins on animal production happens mainly due to losses related to direct effects on animal health and trade losses related to grain rejection. Deoxynivalenol (DON) is a trichothecene mycotoxin that has contaminated approximately 60% of the grains worldwide. Ingestion of DON induces many toxic effects on human and animal health. Detoxification strategies to decrease DON levels in food and feeds include physical and chemical methods; however, they are not very effective when incorporated into the industrial production process. A valuable alternative to achieve this aim is the use of lactic acid bacteria. These bacteria can control fungal growth and thus overcome DON production or can detoxify the mycotoxin through adsorption and biotransformation. Some Lactobacillus spp. strains, such as Lactobacillus plantarum, have demonstrated preventive effects against DON toxicity in poultry and swine. This beneficial effect is associated with a binding capacity of lactic acid bacteria cell wall peptidoglycan with mycotoxins. Moreover, several antifungal compounds have been isolated from L. plantarum supernatants, including lactic, acetic, caproic, phenyl lactic, 3-hydroxylated fatty, and cyclic dipeptide acids. Biotransformation of DON by L. plantarum into other products is also hypothesized, but the mechanism remains unknown. In this concise review, we highlight the use of L. plantarum as an alternative approach to reduce DON levels and toxicity. Although the action mechanism of L. plantarum is still not fully understood, these bacteria are a safe, efficient, and low-cost strategy to reduce economic losses from mycotoxin contamination cases.

HIGHLIGHTS

Plant-Derived Polyphenols as Nrf2 Activators to Counteract Oxidative Stress and Intestinal Toxicity Induced by Deoxynivalenol in Swine: An Emerging Research Direction

The contamination of deoxynivalenol (DON) in feed is a global problem, which seriously threatens the productivity efficiency and welfare of farm animals and the food security of humans. Pig is the most sensitive species to DON, and is readily exposed to DON through its grain-enriched diet. The intestine serves as the first biological barrier to ingested mycotoxin, and is, therefore, the first target of DON. In the past decade, a growing amount of attention has been paid to plant-derived polyphenols as functional compounds against DON-induced oxidative stress and intestinal toxicity in pigs. In this review, we systematically updated the latest research progress in plant polyphenols detoxifying DON-induced intestinal toxicity in swine. We also discussed the potential underlying mechanism of action of polyphenols as Nrf2 activators in protecting against DON-induced enterotoxicity of swine. The output of this update points out an emerging research direction, as polyphenols have great potential to be developed as feed additives for swine to counteract DON-induced oxidative stress and intestinal toxicity.

Lactoferrin Attenuates Intestinal Barrier Dysfunction and Inflammation by Modulating the MAPK Pathway and Gut Microbes in Mice

BACKGROUND

Deoxynivalenol (DON) is a major mycotoxin present in staple foods (particularly in cereal products) that induces intestinal inflammation and disrupts intestinal integrity. Lactoferrin (LF) is a multifunctional protein that contributes to maintaining intestinal homeostasis and improving host health. However, the protective effects of LF on DON-induced intestinal dysfunction remain unclear.

OBJECTIVES

This study aimed to investigate the effects of LF on DON-induced intestinal dysfunction in mice, and its underlying protective mechanism.

METHODS

Male BALB/c mice (5 wk old) with similar body weights were divided into 4 groups (n = 6/group) and treated as follows for 5 wk: Veh [peroral vehicle daily, commercial (C) diet]; LF (peroral 10 mg LF/d, C diet); DON (Veh, C diet containing 12 mg DON/kg); and LF + DON (peroral 10 mg LF/d, DON diet). Intestinal morphology, tight junction proteins, cytokines, and microbial community were determined. Data were analyzed by 2-factor ANOVA or Kruskal-Wallis test.

RESULTS

The DON group exhibited lower final body weight (-12%), jejunal villus height (VH; -41%), and jejunal occludin expression (-36%), and higher plasma IL-1β concentration (+85%) and jejunal Il1b mRNA expression (+98%) compared with the Veh group (P < 0.05). In contrast, final body weight (+19%), jejunal VH (+49%), jejunal occludin (+53%), and intelectin 1 protein expression (+159%) were greater in LF + DON compared with DON (P < 0.05). Additionally, jejunal Il1b mRNA expression (-31%) and phosphorylation of p38 and extracellular signal regulated kinase 1/2 (-40% and - 38%) were lower in LF + DON compared with DON (P < 0.05). Furthermore, the relative abundance of Clostridium XIVa (+181%) and colonic butyrate concentration (+53%) were greater in LF + DON compared with DON (P < 0.05).

CONCLUSIONS

Our study highlights a promising antimycotoxin approach using LF to alleviate DON-induced intestinal dysfunction by modulating the mitogen-activated protein kinase pathway and gut microbial community in mice.

Maize stalk rot caused by Fusarium graminearum alters soil microbial composition and is directly inhibited by Bacillus siamensis isolated from rhizosphere soil

Maize stalk rot caused by Fusarium graminearum can reduce the yield of maize and efficiency of mechanized harvesting. Besides, deoxynivalenol and zearalenone toxins produced by F. graminearum can also affect domestic animals and human health. As chemical fungicides are expensive and exert negative effects on the environment, the use of biological control agents has become attractive in recent years. In the present study, we collected rhizosphere soil with severe stalk rot disease (ZDD), the rhizosphere soil with disease-free near by the ZDD (ZDH), and measured rhizosphere microbial diversity and microbial taxonomic composition by amplicon sequencing targeting either bacteria or fungi. The results showed that Fusarium stalk rot caused by the Fusarium species among which F. graminearum is frequent and can reduce the abundance and alpha diversity of rhizosphere microbial community, and shift the beta diversity of microorganisms. Furthermore, a bacterial strain, Bacillus siamensis GL-02, isolated from ZDD, was found to significantly affect growth of F. graminearum. In vitro and in vivo assays demonstrated that B. siamensis GL-02 had good capability to inhibit F. graminearum. These results revealed that B. siamensis GL-02 could be a potential biocontrol agent for the control of maize stalk rot.

Lactobacillus rhamnosus GG ameliorates DON-induced intestinal damage depending on the enrichment of beneficial bacteria in weaned piglets

BACKGROUND

Deoxynivalenol (DON) is one of the most common environmental pollutants that induces intestinal inflammation and microbiota dysbiosis. Lactobacillus rhamnosus GG (LGG) is a probiotic that not only has anti-inflammatory effects, but also shows protective effect on the intestinal barrier. However, it is still unknown whether LGG exerts beneficial effects against DON-induced intestinal damage in piglets. In this work, a total of 36 weaned piglets were randomized to one of four treatment groups for 21 d. The treatment groups were CON (basal diet); LGG (basal diet supplemented with 1.77 × 10¹¹ CFU/kg LGG); DON (DON-contaminated diet) and LGG + DON (DON-contaminated diet supplemented with 1.77 × 10¹¹ CFU/kg LGG).

RESULT

Supplementation of LGG can enhance growth performance of piglets exposed to DON by improving intestinal barrier function. LGG has a mitigating effect on intestinal inflammation induced by DON exposure, largely through repression of the TLR4/NF-κB signaling pathway. Furthermore, supplementation of LGG increased the relative abundances of beneficial bacteria (e.g., Collinsella, Lactobacillus, Ruminococcus_torques_group and Anaerofustis), and decreased the relative abundances of harmful bacteria (e.g., Parabacteroides and Ruminiclostridium_6), and also promoted the production of SCFAs.

CONCLUSIONS

LGG ameliorates DON-induced intestinal damage, which may provide theoretical support for the application of LGG to alleviate the adverse effects induced by DON exposure.

Protective effects of biological feed additives on gut microbiota and the health of pigs exposed to deoxynivalenol: a review

Deoxynivalenol (DON) is the most common mycotoxin contaminant of cereal-based food and animal feed. The toxicity of DON is very low compared to that of other toxins; however, the most prominent signs of DON exposure include inappetence and body weight loss, which causes considerable economic losses in the livestock industry. This review summarizes critical studies on biological DON mycotoxin mitigation strategies and the respective in vitro and in vivo intestinal effects. Focus areas include growth performance, gut health in terms of intestinal histomorphology, epithelial barrier functions, the intestinal immune system and microflora, and short-chain fatty acid production in the intestines. In addition, DON detoxification and modulation of these parameters, through biological supplements, are discussed. Biological detoxification of DON using microorganisms can attenuate DON toxicity by modulating gut microbiota and improving gut health with or without influencing the growth performance of pigs. However, the use of microorganisms as feed additives to livestock for mycotoxins detoxification needs more research before commercial use.

Deoxynivalenol triggers porcine intestinal tight junction disorder through hijacking SLC5A1 and PGC1α-mediated mitochondrial function

Deoxynivalenol (DON) is a mycotoxin frequently occurring in human and animal food worldwide, which raises increasing public health concerns. Growing evidence suggests that mitochondria is a pivotal molecular target for DON. However, the contribution of mitochondrial dysfunction to the pathogenesis of DON-induced gut epithelial barrier disruption remains poorly understood. In an animal experiment, piglets exposed to 2.89 mg DON/kg feed for 4 weeks showed altered metabolomic profiling in the serum and compromised transcriptome in the jejunum. DON exposure also impaired mitochondrial structure in the jejunal mucosa, corresponding with dysfunction of the tight junctions. In IPEC-J2 cells, metabolomic and transcriptomic analyses revealed that DON exposure perturbed biological processes occurring in the mitochondria and disordered the expression of genes involved in mitochondrial energy metabolism. Fuel utilization from glucose was affected by DON exposure, as were mitochondrial morphological dynamics leading to increased fragmentation. A marked loss of Na⁺/glucose cotransporter (SLC5A1) and peroxisome proliferator activated receptor-γ co-activator 1α (PGC1α) was observed in DON-treated cells. Taken together, our data highlight the critical role of impaired mitochondrial energy metabolism and mitochondrial biogenesis in abnormal intestinal tight junction upon DON exposure, and provide a potential mitochondrial target for intestinal mucosal restoration following DON exposure.

Crystal structure and biochemical analysis of the specialized deoxynivalenol-detoxifying glyoxalase SPG from Gossypium hirsutum

Deoxynivalenol (DON) and its acetylated derivatives such as 3-acetyldeoxynivalenol (3A-DON) and 15-acetyldeoxynivalenol (15A-DON) are notorious mycotoxins in Fusarium contaminated cereals, which pose a great threat to human and livestock health. The specialized glyoxalase I from Gossypium hirsutum (SPG) can lower the toxicity of 3A-DON by conducting isomerization to transfer C8 carbonyl to C7 and double bond from C9-C10 to C8-C9. Here we report that the substrate-flexible SPG can also recognize 15A-DON and DON, probably following the same isomerization mechanism as that for 3A-DON. The crystallographic, mutagenesis, and biochemical analyses revealed that SPG provides a hydrophobic pocket to accommodate the substrate and residue E167 might serve as the catalytic base. A variant SPGY62A that was constructed based on structure-based protein engineering exhibited elevated catalytic activity towards DON, 3A-DON, and 15A-DON by >70%. Furthermore, variant SPGY62A was successfully expressed in Pichia pastoris, whose catalytic activity was also compared to that produced in Escherichia coli. These results provide a blueprint for further protein engineering of SPG and reveal the potential applications of the enzyme in detoxifying DON, 3A-DON and 15A-DON.

Phenethyl isothiocyanate as an anti-nutritional factor attenuates deoxynivalenol-induced IPEC-J2 cell injury through inhibiting ROS-mediated autophagy

Deoxynivalenol (DON) is considered to be the most harmful mycotoxin that affects the intestinal health of animals and humans. Phenethyl isothiocyanate (PEITC) in feedstuff is an anti-nutritional factor and impairs nutrient digestion and absorption in the animal intestinal. In the current study, we aimed to explore the effects of PEITC on DON-induced apoptosis, intestinal tight junction disorder, and its potential molecular mechanism in the porcine jejunum epithelial cell line (IPEC-J2). Our results indicated that PEITC treatment markedly alleviated DON-induced cytotoxicity, decreasing the apoptotic cell percentage and pro-apoptotic mRNA/protein levels, and increasing zonula occludens-1 (ZO-1), occludin and claudin-1 mRNA/protein expression. Meanwhile, PEITC treatment ameliorated DON-induced an increase of the inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) mRNA levels and intracellular reactive oxygen species (ROS) level, and a decrease of glutathione peroxidase 1 (GPx1), superoxide dismutase 2 (SOD2), catalase (CAT) and heme oxygenase 1 (HO-1) mRNA levels. Additionally, PEITC treatment significantly down-regulated autophagy-related protein 5 (ATG5), beclin-1 and microtubule-associated protein 1 light chain 3B (LC3-Ⅱ) mRNA/protein levels, decreased the number of green fluorescent protein-microtubule-associated protein 1 light-chain 3 (GFP-LC3) puncta and phosphatidylinositol 3 kinase (PI3K) protein expression, and up-regulated phospho-protein kinase B (p-Akt) and phospho-mammalian target of rapamycin (p-mTOR) protein expression against DON. However, the activation of autophagy by rapamycin, an autophagy agonist, abolished the protective effects of PEITC against DON-induced cytotoxicity, apoptosis and intestinal tight junction disorder. Collectively, PEITC could confer protection against DON-induced porcine intestinal epithelial cell injury by suppressing ROS-mediated autophagy.

Allicin Improves Intestinal Epithelial Barrier Function and Prevents LPS-Induced Barrier Damages of Intestinal Epithelial Cell Monolayers

Gut barrier disruption is the initial pathogenesis of various diseases. We previously reported that dietary allicin improves tight junction proteins in the endoplasmic reticulum stressed jejunum. However, whether the allicin benefits the gut barrier within mycotoxin or endotoxin exposure is unknown. In the present study, IPEC-J2 cell monolayers within or without deoxynivalenol (DON) or lipopolysaccharide (LPS) challenges were employed to investigate the effects of allicin on intestinal barrier function and explore the potential mechanisms. Results clarified that allicin at 2 μg/mL increased the viability, whereas the allicin higher than 10 μg/mL lowered the viability of IPEC-J2 cells via inhibiting cell proliferation. Besides, allicin increased trans-epithelial electric resistance (TEER), decreased paracellular permeability, and enhanced ZO-1 integrity of the IPEC-J2 cell monolayers. Finally, allicin supplementation prevented the LPS-induced barrier damages via activating Nrf2/HO-1 pathway-dependent antioxidant system. In conclusion, the present study strongly confirmed allicin as an effective nutrient to improve intestinal barrier function and prevent bacterial endotoxin-induced barrier damages.

Ellagic acid ameliorates paraquat-induced liver injury associated with improved gut microbial profile

Paraquat, a widely used herbicide, causes environmental pollution, and liver injury in humans and animals. As a natural compound in fruits, ellagic acid (EA) shows anti-inflammatory and antioxidant effects. This study examines the beneficial effects of dietary EA against the paraquat-induced hepatic injury and further explores the underlying molecular mechanisms using a piglet model. Post-weaning piglets are fed basal diet supplemented with 50 mg/kg, 100 mg/kg, or 200 mg/kg EA for 3 weeks. At week 2, hepatic injury is induced by 4 mg/kg paraquat followed by 7 days recovery. EA supplementation significantly mitigates paraquat-induced hepatic fibrosis, steatosis, and high apoptotic rate. In agreement, EA supplementation reduces serum pro-inflammatory levels, ameliorates inflammatory cells infiltration into hepatic tissue, which are associated with suppressed NF-κB signaling during paraquat exposure. In addition, EA supplementation significantly improves activities of antioxidative enzymes which were correlated with activated Nrf2/Keap 1 signaling during paraquat exposure. Furthermore, EA supplementation restores cecal microbial community during paraquat exposure. The protective effect of EA is strongly linked with increased relative abundance of Lactobacillus reuteri and Lactobacillus amylovorus. Taken together, EA supplementation effectively reduced the occurrence of hepatic oxidative damage and inflammation induced by paraquat through modulating cecal microbial communities, which provides a novel nutritional therapeutic strategy for hepatic injury.

Biological Function of Short-Chain Fatty Acids and Its Regulation on Intestinal Health of Poultry

Short-chain fatty acids (SCFAs) are metabolites generated by bacterial fermentation of dietary fiber (DF) in the hindgut. SCFAs are mainly composed of acetate, propionate and butyrate. Many studies have shown that SCFAs play a significant role in the regulation of intestinal health in poultry. SCFAs are primarily absorbed from the intestine and used by enterocytes as a key substrate for energy production. SCFAs can also inhibit the invasion and colonization of pathogens by lowering the intestinal pH. Additionally, butyrate inhibits the expression of nitric oxide synthase (NOS), which encodes inducible nitric oxide synthase (iNOS) in intestinal cells via the PPAR-γ pathway. This pathway causes significant reduction of iNOS and nitrate, and inhibits the proliferation of Enterobacteriaceae to maintain overall intestinal homeostasis. SCFAs can enhance the immune response by stimulating cytokine production (e.g. TNF-α, IL-2, IL-6, and IL-10) in the immune cells of the host. Similarly, it has been established that SCFAs promote the differentiation of T cells into T regulatory cells (Tregs) and expansion by binding to receptors, such as Toll-like receptors (TLR) and G protein-coupled receptors (GPRs), on immune cells. SCFAs have been shown to repair intestinal mucosa and alleviate intestinal inflammation by activating GPRs, inhibiting histone deacetylases (HDACs), and downregulating the expression of pro-inflammatory factor genes. Butyrate improves tight-junction-dependent intestinal barrier function by promoting tight junction (TJ) assembly. In recent years, the demand for banning antibiotics has increased in poultry production. Therefore, it is extremely important to maintain the intestinal health and sustainable production of poultry. Taking nutrition strategies is important to regulate SCFA production by supplementing dietary fiber and prebiotics, SCFA-producing bacteria (SPB), and additives in poultry diet. However, excessive SCFAs will lead to the enteritis in poultry production. There may be an optimal level and proportion of SCFAs in poultry intestine, which benefits to gut health of poultry. This review summarizes the biological functions of SCFAs and their role in gut health, as well as nutritional strategies to regulate SCFA production in the poultry gut.

The toxicity mechanisms of DON to humans and animals and potential biological treatment strategies

Deoxynivalenol, also known as vomitotoxin, is produced by Fusarium, belonging to the group B of the trichothecene family. DON is widely polluted, mainly polluting cereal crops such as wheat, barley, oats, corn and related cereal products, which are closely related to lives of people and animals. At present, there have been articles summarizing DON induced toxicity, biological detoxification and the protective effect of natural products, but there is no systematic summary of this information. In addition to ribosome and endoplasmic reticulum, recent investigations support that mitochondrion is also organelles that DON can damage. DON can't directly act on mitochondria, but can indirectly cause mitochondrial damage and changes through other means. DON can indirectly inhibit mitochondrial biogenesis and mitochondrial electron transport chain activity, ATP production, and mitochondrial transcription and translation. This review will provide the latest progress on mitochondria as the research object, and systematically summarizes all the toxic mechanisms of DON. Here, we discuss DON induced mitochondrial-mediated apoptosis and various mitochondrial toxicity. For the toxicity of DON, many methods have been derived to prevent or reduce the toxicity. Biological detoxification and the antioxidant effect of natural products are potentially effective treatments for DON toxicity.

Phytic acid modulates the morphology, immunological response of cytokines and β-defensins in porcine intestine exposed to deoxynivalenol and fumonisin B1

Occurrence of mycotoxins in agricultural products represents a risk for human and animal health. Therefore, there is a requirement of strategies to mitigate their harmful impacts. This study investigated the effects of phytic acid (IP6) on the immunological response of pro-(interleukin (IL)-1β, IL-6, IL-8, IL-10, interferon (IFN)-γ, tumour necrosis factor (TNF)-α) and anti-inflammatory (IL-10) cytokines and β-defensins 1 (pBD-1) and 2 (pBD-2) in porcine jejunal explants exposed to deoxynivalenol (DON) and fumonisin B1 (FB1). The explants were exposed to the following treatments: control, DON (10 μM), DON plus IP6 2.5 mM or 5 mM, FB1 (70 μM), FB1 IP6 plus 2.5 or 5 mM. The expression levels of the cytokines were measured by RT-qPCR. The exposure to FB1 and DON induced intestinal lesions. The presence of 2.5 and 5 mM IP6 inhibited the morphological changes induced by the mycotoxins. The explants exposed to DON showed an increase in the expression of IL-1β and IL-8 and a decrease in the levels of IL-6, IFN-γ, IL-10 and pBD-2. IP6 (5 mM) decreased the expression of IL-8 and increased the expression in pBD-1 and 2 compared to DON alone. FB1 induced a significant decrease in the levels of most of the pro-inflammatory cytokines, IL-10 and pBD-1, and an increase in IL-1β expression. The addition of IP6 5 mM induced significant increase in TNF-α expression compared to FB1. Taken together, the results suggest IP6 modulates immunological changes induced by DON and FB1 on intestinal mucosa resulting in beneficial effects that contribute to intestinal homeostasis and health.

Ginsenoside Rb1 prevents deoxynivalenol-induced immune injury via alleviating oxidative stress and apoptosis in mice

Deoxynivalenol (DON) is considered to be a grave threat to humans and animals. Ginsenoside Rb1 (Rb1) has been reported for its antioxidant potential and medicinal properties. However, the shielding effects of Rb1 and the precise molecular mechanisms against DON-induced immunotoxicity in mice have not been reported yet. In the present research, 4-weeks old healthy C57BL/6 mice were randomly assigned into four experimental groups (n = 12), viz., CON, DON 3 mg/kg BW, Rb1 50 mg/kg BW and DON 3 mg/kg + Rb1 50 mg/kg BW (DON + Rb1). Feed intake and body weight gain were monitored during the entire experiment (15 d). Our results demonstrated that Rb1 markedly increased the ADG (30%) and ADFI (25.10%) of mice compared with DON group. Furthermore, Rb1 alleviated the DON-induced immune injury by relieving the splenic histopathological alteration, enhancing the T-lymphocytes subsets (CD4⁺, CD8⁺), the levels of cytokines (IL-2, IL-6, IFN-γ, and TNF-α), as well as production of immunoglobulins (IgA, IgM, and IgG). Moreover, Rb1 ameliorated DON-inflicted oxidative stress by reducing the ROS, MDA and H₂O₂ contents and boosting the antioxidant defense system (T-AOC, T-SOD, CAT, and GSH-Px). Additionally, Rb1 significantly reversed the DON-induced excessive splenic apoptosis via modulating the mitochondria-mediated apoptosis pathway in mice, depicting the decreased percentage of splenocyte apoptotic cells by 26.65%, down-regulated the mRNA abundance of Bax, caspase-3, caspase-9, and protein expression of Bax, cleaved caspase-3, and Cyt-c. Simultaneously, Rb1 markedly rescued both Bcl-2 mRNA and protein expression levels. Taken together, Rb1 mitigates DON-induced immune injury by suppressing the oxidative damage and regulating the mitochondria-mediated apoptosis pathway in mice. Conclusively, our current research provides an insight into the preventive mechanism of Rb1 against DON-induced immune injury in mice and thus, presents a scientific baseline for the therapeutic application of Rb1.

Deoxynivalenol exposure induces liver damage in mice: Inflammation and immune responses, oxidative stress, and protective effects of Lactobacillus rhamnosus GG

Deoxynivalenol (DON), one of the most common environmental pollutants, substantially affects human and animal health. Much attention has been paid to the ability of probiotics to modulate inflammation and immune responses. In this work, the toxic effects of DON on the liver and the protective effects of Lactobacillus rhamnosus GG (LGG) were investigated. We treated mice with oral gavage of DON (2.4 mg/kg bw/day), LGG (1 × 10⁹ CFU/mouse/day) or both for 28 days. The results showed that DON triggered liver inflammation, reflected by pathological changes and liver function damage but LGG oral administration significantly attenuated these changes. Notably, DON treatment activated the TLR4/NF-κB signaling pathway which contribute to produce inflammatory cytokines, but oral administration of LGG inhibited all the effects of DON. DON treatment can also induce oxidative stress and activate Keap1-Nrf2 signaling pathway, leading to the activation of Nrf2 and the downstream genes, while LGG treatment can improve the antioxidant capacity of liver and protected mice from DON injury. In conclusion, LGG was able to negate the detrimental effects of DON on the liver and may contribute as a potential dietary intervention strategy to reduce mycotoxicity.

Deoxynivalenol photocatalytic detoxification products alleviate intestinal barrier damage and gut flora disorder in BLAB/c mice

Deoxynivalenol (DON), a trichothecene mycotoxin, is one of the most globally prevalent mycotoxins mainly produced by Fusarium species. DON exposure can cause spectrum of symptoms such as nausea, vomiting, gastroenteritis, growth retardation, immunosuppression, and intestinal flora disorders in humans and animals. Therefore, the implication of DON degradation technology is of great significance for food safety. Recently, photocatalytic degradation technology has been applied for DON control. However, the toxicity of the intermediates identified in the degradation process was often ignored. In this work, based on previous successful degradation of DON and evaluation of the in vitro toxicity of DON photocatalytic detoxification products (DPDPs), we further studied the in vivo toxicity of DPDPs and mainly explored their effects on intestinal barrier function and intestinal flora in mice. The results demonstrated that the DPDPs treated with photocatalyst for 120 min effectively increased the expression of intestinal tight junction proteins and improved the disorder of gut flora. Meanwhile, compared with DON-exposed mice, the DPDPs reduced the level of inflammation and oxidative stress of intestinal tissue, and improved growth performance, enterohepatic circulation, energy metabolism, and autonomic activity. All the results indicated that the toxicity of the DPDPs irradiated for 120 min was much lower than that of DON or even nontoxic. Therefore, we hope that this photocatalytic degradation technology can be used as a promising tool for the detoxification of mycotoxins.

Luteolin Alleviates AflatoxinB1-Induced Apoptosis and Oxidative Stress in the Liver of Mice through Activation of Nrf2 Signaling Pathway

Aflatoxin B1 (AFB1), a threatening mycotoxin, usually provokes oxidative stress and causes hepatotoxicity in animals and humans. Luteolin (LUTN), well-known as an active phytochemical agent, acts as a strong antioxidant. This research was designed to investigate whether LUTN exerts protective effects against AFB1-induced hepatotoxicity and explore the possible molecular mechanism in mice. A total of forty-eight mice were randomly allocated following four treatment groups (n = 12): Group 1, physiological saline (CON). Group 2, treated with 0.75 mg/kg BW aflatoxin B1 (AFB1). Group 3, treated with 50 mg/kg BW luteolin (LUTN), and Group 4, treated with 0.75 mg/kg BW aflatoxin B1 + 50 mg/kg BW luteolin (AFB1 + LUTN). Our findings revealed that LUTN treatment significantly alleviated growth retardation and rescued liver injury by relieving the pathological and serum biochemical alterations (ALT, AST, ALP, and GGT) under AFB1 exposure. LUTN ameliorated AFB1-induced oxidative stress by scavenging ROS and MDA accumulation and boosting the capacity of the antioxidant enzyme (CAT, T-SOD, GSH-Px and T-AOC). Moreover, LUTN treatment considerably attenuates the AFB1-induced apoptosis in mouse liver, as demonstrated by declined apoptotic cells percentage, decreased Bax, Cyt-c, caspase-3 and caspase-9 transcription and protein with increased Bcl-2 expression. Notably, administration of LUTN up-regulated the Nrf2 and its associated downstream molecules (HO-1, NQO1, GCLC, SOD1) at mRNA and protein levels under AFB1 exposure. Our results indicated that LUTN effectively alleviated AFB1-induced liver injury, and the underlying mechanisms were associated with the activation of the Nrf2 signaling pathway. Taken together, LUTN may serve as a potential mitigator against AFB1-induced liver injury and could be helpful for the development of novel treatment to combat liver diseases in humans and/or animals.

Hepatotoxicity of food-borne mycotoxins: molecular mechanism, anti-hepatotoxic medicines and target prediction

Mycotoxins are metabolites produced by fungi. The widespread contamination of food and feed by mycotoxins is a global food safety problem and a serious threat to people's health. Most food-borne mycotoxins have strong hepatotoxicity. However, no effective methods have been found to prevent or treat Mycotoxin- Induced Liver Injury (MILI) in clinical and animal husbandry. In this paper, the molecular mechanisms and potential anti-MILI medicines of six food-borne MILI are reviewed, and their targets are predicted by network toxicology, which provides a theoretical basis for further study of the toxicity mechanism of MILI and the development of effective strategies to manage MILI-related health problems in the future and accelerate the development of food safety.

Mechanism of deoxynivalenol mediated gastrointestinal toxicity: Insights from mitochondrial dysfunction

Deoxynivalenol (DON) is a mycotoxin predominantly produced by Fusarium genus, and widely contaminates cereals and associated products all over the world. The intestinal toxicity of DON is well established. However, intestinal homeostasis involves mitochondria, which has rarely been considered in the context of DON exposure. We summarize the recent knowledge on mitochondria as a key player in maintaining intestinal homeostasis based on their functions in cellular energy metabolism, redox homeostasis, apoptosis, intestinal immune responses, and orchestrated bidirectional cross-talk with gut microbe. In addition, we discuss the pivotal roles of mitochondrial dysfunction in the intestinal toxicity of DON and highlight promising mitochondrial-targeted therapeutics for DON-induced intestinal injury. Recent studies support that the intestinal toxicity of DON is attributed to mitochondrial dysfunction as a critical factor. Mitochondrial dysfunction characterized by failure in respiratory capacities and ROS overproduction has been demonstrated in intestinal cells exposed to DON. Perturbation of mitochondrial respiration leading to ROS accumulation is implicated in the early initiation of apoptosis. DON-induced intestinal inflammatory response is tightly linked to the mitochondrial ROS, whereas immunosuppression is intimately associated with mitophagy inhibition. DON perturbs the orchestrated bidirectional cross-talk between gut microbe and host mitochondria, which may be involved in DON-induced intestinal toxicity.