A chronic oral exposure of pigs with deoxynivalenol partially prevents the acute effects of lipopolysaccharides on hepatic histopathology and blood clinical chemistry

Dynamic Mechanical Load as a Trigger for Growth and Proliferation in Porcine Epithelial Cells

The impact of gravity is a basic force determining our existence on Earth. Changes in orientation with respect to the gravity vector trigger alternating mechanical forces on organisms, organs, and cells. In the intestines of mammals, epithelial cells are continuously exposed to changed orientations to gravity. In this study, we employed dynamic cultivation systems to mimic the load changes and the resulting mechanical forces. The morphological and functional response of non-cancer-derived porcine epithelial cell lines IPEC-1 and IPEC-J2 was analyzed. We found that dynamic growth conditions affect morphology in the enterocyte model IPEC-1 but not in IPEC-J2. Changes in IPEC-1 were accompanied by modifications of the distribution and structure of the F-actin cytoskeleton rather than the amount. The structure of the apical brush border and the tight junction system seemed to be largely unaffected; however, a robust decrease in transepithelial resistance was found in IPEC-1 and partially in IPEC-J2. We further detected an increase in Ki67, pointing towards accelerated proliferation. In line with this finding, we detected a doubling of cellular mitochondrial respiration, which was not linked to a general increase in the respiratory chain capacity. Dynamic cultivation of confluent epithelial cell layers did not evoke signs of senescence. In summary, we identified the mechanical load cycle as a relevant parameter for the modulation of the morphological structure and physiological behaviour of intestinal epithelial cells.

Necroptosis contributes to deoxynivalenol-induced liver injury and inflammation in weaned piglets

BACKGROUND

The aim of this study was to investigate the role of necroptosis in deoxynivalenol (DON)-induced liver injury and inflammation in weaned piglets.

METHODS

In Exp. 1, 12 weaned piglets were divided into 2 groups including pigs fed basal diet and pigs fed diet contaminated with 4 mg/kg DON for 21 d. In Exp. 2, 12 weaned piglets were divided into 2 groups including control piglets and piglets given a gavage of 2 mg/kg body weight (BW) DON. In Exp. 3, 24 weaned piglets were used in a 2 × 2 factorial design and the main factors including necrostatin-1 (Nec-1) (DMSO or 0.5 mg/kg BW Nec-1) and DON challenge (saline or 2 mg/kg BW DON gavage). On 21 d in Exp. 1, or at 6 h post DON gavage in Exp. 2 and 3, pigs were killed for blood samples and liver tissues. Liver histology, blood biochemical indicators, and liver inflammation and necroptosis signals were tested.

RESULTS

Dietary or oral gavage with DON caused liver morphological damage in piglets. Dietary DON led to hepatocyte damage indicated by increased aspartate transaminase (AST) activity and AST/alanine aminotransferase (ALT) ratio, and DON gavage also caused hepatocyte damage and cholestasis indicated by increased AST and alkaline phosphatase (AKP) activities. Dietary DON caused liver necroptosis indicated by increased protein abundance of total receptor interacting protein kinase 3 (t-RIP3) and total mixed lineage kinase domain-like protein (t-MLKL). Moreover, DON gavage increased mRNA expression of interleukin (IL)-6 and IL-1β in liver. DON gavage also induced liver necroptosis demonstrated by increased protein abundance of t-RIP3, phosphorylated-RIP3 (p-RIP3), t-MLKL and p-MLKL. However, pretreatment with Nec-1, a specific inhibitor of necroptosis, inhibited liver necroptosis indicated by decreased protein expression of t-RIP3, p-RIP3, t-MLKL and p-MLKL. Nec-1 pretreatment reduced liver morphological damage after DON gavage. Pretreatment with Nec-1 also attenuated liver damage induced by DON indicated by decreased activities of AST and AKP. Furthermore, Nec-1 pretreatment inhibited liver mRNA expression of IL-6 and IL-1β after DON challenge.

CONCLUSIONS

Our data demonstrate for the first time that necroptosis contributes to DON-induced liver injury and inflammation in piglets.

Vitamin 25(OH)D3, E, and C Supplementation Impact the Inflammatory and Antioxidant Responses in Piglets Fed a Deoxynivalenol-Contaminated Diet and Challenged with Lipopolysaccharides

Using alternative ingredients or low-quality grain grades to reduce feeding costs for pig diets can introduce mycotoxins such as deoxynivalenol (DON) into feed, which is known to induce anorexia, inflammation, and oxidative stress. Adding vitamin 25(OH)D3 or vitamins E and C to the feed could increase piglets' immune system to alleviate the effects of DON. This study used 54 pigs (7.8 ± 0.14 kg) in 27 pens (2 pigs/pen) with a vitamin 25(OH)D3 or vitamin E-C supplementation, or their combination, in DON-contaminated (5.1 mg/kg) feed ingredients over 21 days followed by a lipopolysaccharide (LPS) challenge (20 µg/kg BW) 3 h prior to euthanasia for 1 piglet per pen. DON contamination induced anorexia, which reduced piglet growth. DON also induced immunomodulation, oxidative stress, and downregulated vitamin D status. The vitamin E and C supplementation and the combination of vitamins E, C, and 25(OH)D3 provided protection against DON contamination by not only decreasing blood and liver oxidative stress markers, but also by increasing antioxidant enzymes and tocopherol levels in blood, indicating improved antioxidant defense mechanisms. The combination of vitamins also restored the vitamin D status. After LPS challenge, DON contamination decreased intestinal and liver antioxidant statuses and increased inflammation markers. The addition of vitamins E and C to DON-contaminated feed reduced markers of inflammation and improved the antioxidant status after the LPS immune stimulation. The combination of all these vitamins also reduced the oxidative stress markers and the inflammation in the intestine and mesenteric lymph nodes, suggesting an anti-inflammatory effect.

Vitamin D Supplementation Impacts Calcium and Phosphorus Metabolism in Piglets Fed a Diet Contaminated with Deoxynivalenol and Challenged with Lipopolysaccharides

Using alternative feed ingredients in pig diets can lead to deoxynivalenol (DON) contamination. DON has been shown to induce anorexia, inflammation, and-more recently-alterations in the vitamin D, calcium, and phosphorus metabolisms. Adding vitamin D supplementation in the form of vitamin D₃ and 25-OH-D₃ to the feed could modify the effects of DON in piglets. In this study, vitamin D₃ or 25-OH-D₃ supplementation was used in a control or DON-contaminated treatment. A repetitive exposure over 21 days to DON in the piglets led to disruptions in the vitamin D, calcium, and phosphorus metabolisms, resulting in a decreased growth performance, increased bone mineralization, and the downregulation of genes related to calcium and to phosphorus intestinal and renal absorption. The DON challenge also decreased blood concentrations of 25-OH-D₃, 1,25-(OH)₂-D₃, and phosphate. The DON contamination likely decreased the piglets' vitamin D status indirectly by modifying the calcium metabolism response. Vitamin D supplementations did not restore vitamin D status or bone mineralization. After a lipopolysaccharide-induced inflammatory stimulation, feeding a 25-OH-D₃ supplementation increased 25-OH-D₃ concentration and 1,25-(OH)₂-D₃ regulations during the DON challenge. DON contamination likely induced a Ca afflux by altering the intestinal barrier, which resulted in hypercalcemia and hypovitaminosis D. The vitamin D supplementation could increase the calcitriol production to face the combined LPS and DON challenge.

Natural mycotoxin contamination in dog food: A review on toxicity and detoxification methods

Nowadays, the companion animals (dogs or other pets) are considered as members of the family and have established strong emotional relationships with their owners. Dogs are long lived compared to food animals, so safety, adequacy, and efficacy of dog food is of great importance for their health. Cereals, cereal by-products as well as feedstuffs of plant origin are commonly employed food resources in dry food, yet are potential ingredients for mycotoxins contamination, so dogs are theoretically more vulnerable to exposure when consumed daily. Aflatoxins (AF), deoxynivalenol (DON), fumonisins (FUM), ochratoxin A (OTA), and zearalenone (ZEA) are the most frequent mycotoxins that might present in dog food and cause toxicity on the growth and metabolism of dogs. An understanding of toxicological effects and detoxification methods (physical, chemical, or biological approaches) of mycotoxins will help to improve commercial ped food quality, reduce harm and minimize exposure to dogs. Herein, we outline a description of mycotoxins detected in dog food, toxicity and clinical findings in dogs, as well as methods applied in mycotoxins detoxification. This review aims to provide a reference for future studies involved in the evaluation of the risk, preventative strategies, and clear criteria of mycotoxins for minimizing exposure, reducing harm, and preventing mycotoxicosis in dog.

Cytochrome P450 enzymes mediated by DNA methylation is involved in deoxynivalenol-induced hepatoxicity in piglets

Deoxynivalenol (DON) is an inevitable contaminant in animal feed and can lead to liver damage, then decreasing appetite and causing growth retardation in piglets. Although many molecular mechanisms are related to hepatoxicity caused by DON, few studies have been done on cytochrome P450 (CYP450) enzymes and DNA methylation. To explore the role of CYP450 enzymes and DNA methylation in DON-induced liver injury, male piglets were fed a control diet, or diet containing 1.0 or 3.0 mg/kg DON for 4 weeks. DON significantly raised the activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutamyl transpeptidase (GGT) (P < 0.01), leading to liver injury. In vivo study found that DON exposure increased the expression of CYP450 enzymes (such as CYP1A1, CYP2E1, CYP3A29) (P < 0.05), and disturbed the expression of nicotinamide N-methyltransferase (NNMT), galanin-like peptide (GALP) and insulin-like growth factor 1 (IGF-1) (P < 0.05), in which DNA methylation affected the expression of these genes. In vitro study (human normal hepatocytes L02) further proved that DON elevated the expression of CYP1A1, CYP2E1 and CYP3A4 (P < 0.05), and inhibited cell growth in a dose-dependent manner, resulting in cell necrosis. More importantly, knockdown of CYP1A1 or CYP2E1 could alleviate DON-induced growth inhibition by promoting IGF-1 expression. Taken together, increased CYP450 enzymes expression was one of the mechanisms of hepatoxicity and growth inhibition induced by DON, suggesting that the decrease of CYP450 enzymes can antagonize the hepatoxicity in animals, which provides some value for animal feed safety.

Molecular RNA Correlates of the SOFA Score in Patients with Sepsis

The most common scoring system for critically ill patients is the Sequential Organ Failure Assessment (SOFA) score. Little is known about specific molecular signaling networks underlying the SOFA criteria. We characterized these networks and identified specific key regulatory molecules. We prospectively studied seven patients with sepsis and six controls with high-throughput RNA sequencing (RNAseq). Quantitative reverse transcription PCR (RT-qPCR) confirmation was performed in a second independent cohort. Differentially and significantly expressed miRNAs and their target mRNA transcripts were filtered for admission SOFA criteria and marker RNAs for the respective criteria identified. We bioinformatically constructed molecular signaling networks specifically reflecting these criteria followed by RT-qPCR confirmation of RNAs with important regulatory functions in the networks in the second cohort. RNAseq identified 82 miRNAs (45% upregulated) and 3254 mRNAs (50% upregulated) differentially expressed between sepsis patients and controls. Bioinformatic analysis characterized 6 miRNAs and 76 mRNA target transcripts specific for the SOFA criteria. RT-qPCR validated miRNA and mRNAs included IGFBP2 (respiratory system); MMP9 and PDE4B (nervous system); PPARG (cardiovascular system); AKR1B1, ANXA1, and LNC2/NGAL (acute kidney injury); GFER/ALR (liver); and miR-30c-3p (coagulopathy). There are specific canonical networks underlying the SOFA score. Key regulatory miRNA and mRNA transcripts support its biologic validity.

The Influence of Fusarium Mycotoxins on the Liver of Gilts and Their Suckling Piglets

Simple Summary

Mycotoxins are toxic secondary metabolites of fungi that frequently contaminate animal feed and human food in different combinations; therefore, it is of great importance to determine the effects of mycotoxin co-contamination. Pigs are one of the most sensitive animal species to Fusarium mycotoxins, and the liver is an important site of mycotoxin metabolism. The objective of the present research was to determine histopathological changes, apoptosis, and proliferation in the liver of gilts fed with Fusarium mycotoxin-contaminated feed for a prolonged time at the end of their pregnancy and until weaning of their piglets. Additionally, the same parameters were evaluated in the liver of their piglets to determine whether Fusarium mycotoxins would affect the offspring. The results revealed increased hepatocellular necrosis and apoptosis as well as sinusoidal leukocytosis with inflammatory infiltrates of hepatic lobules in experimental gilts, but no significant changes were observed in the piglet livers, implying that the utilized concentrations and duration of exposure did not cause detrimental effects on them. Interestingly, the amount of interlobular connective tissue in the liver of experimental gilts was significantly decreased. The obtained results emphasized the need to evaluate Fusarium mycotoxin concentrations in feed because even at low concentrations, they can cause adverse effects, but there is less concern for severe detrimental effects on the offspring.

Abstract

Mycotoxins are common fungal secondary metabolites in both animal feed and human food, representing widespread toxic contaminants that cause various adverse effects. Co-contamination with different mycotoxins is frequent; therefore, this study focused on feed contaminated with Fusarium mycotoxins, namely, deoxynivalenol (5.08 mg/kg), zearalenone (0.09 mg/kg), and fusaric acid (21.6 mg/kg). Their effects on the liver of gilts and their piglets were chosen as the research subject as pigs are one of the most sensitive animal species that are also physiologically very similar to humans. The gilts were fed the experimental diet for 54 ± 1 day, starting late in their pregnancy and continuing until roughly a week after weaning of their piglets. Livers of gilts and their piglets were assessed for different histopathological changes, apoptosis, and proliferation activity of hepatocytes. On histopathology, gilts fed the experimental diet had a statistically significant increase in hepatocellular necrosis and apoptosis (p = 0.0318) as well as sinusoidal leukocytosis with inflammatory infiltrates of hepatic lobules (p = 0.0004). The amount of interlobular connective tissue in the liver of experimental gilts was also significantly decreased (p = 0.0232), implying a disruption in the formation of fibrous connective tissue. Apoptosis of hepatocytes and of cells in hepatic sinusoids, further assessed by the terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, showed a statistically significant increase (p = 0.0224 and p = 0.0007, respectively). No differences were observed in piglet livers. These results indicated that Fusarium mycotoxins elicited increased apoptosis, necrosis, and inflammation in the liver of gilts, but caused no effects on the liver of piglets at these concentrations.

Does chronic dietary exposure to the mycotoxin deoxynivalenol affect the porcine hepatic transcriptome when an acute-phase response is initiated through first or second-pass LPS challenge of the liver?

The sensitivity of pigs to deoxynivalenol (DON) might be increased by systemic inflammation (SI), which also has consequences for hepatic integrity. Liver lesions and a dys-regulated gene network might hamper hepatic handling and elimination of DON whereby the way of initiation of hepatic inflammation might play an additional role. First and second-pass exposure of the liver with LPS for triggering a SI was achieved by LPS infusion via pre- or post-hepatic venous route, respectively. Each infusion group was pre-conditioned either with a control diet (0.12 mg DON/kg diet) or with a DON-contaminated diet (4.59 mg DON/kg diet) for 4 wk. Liver transcriptome was evaluated at 195 min after starting infusions. DON exposure alone failed to modulate the mRNA expression significantly. However, pre- and post-hepatic LPS challenges prompted transcriptional responses in immune and metabolic levels. The mRNAs for B-cell lymphoma 2-like protein 11 as a key factor in apoptosis and IFN-γ released by T cells were clearly up-regulated in DON-fed group infused with LPS post-hepatically. On the other hand, mRNAs for nucleotide binding oligomerization domain containing 2, IFN-α and eukaryotic translation initiation factor 2α kinase 3 as ribosomal stress sensors were exclusively up-regulated in control pigs with pre-hepatic LPS infusion. These diverse effects were traced back to differences in TLR4 signalling.

Effects of Deoxynivalenol and Zearalenone on the Histology and Ultrastructure of Pig Liver

The purpose of this study was to determine the effects of single and combined administrations of deoxynivalenol (DON) and zearalenone (ZEN) on the histology and ultrastructure of pig liver. The study was performed on immature gilts, which were divided into four equal groups. Animals in the experimental groups received DON at a dose of 12 μg/kg body weight (BW) per day, ZEN at 40 μg/kg BW per day, or a mixture of DON (12 μg/kg BW per day) and ZEN (40 μg/kg BW). The control group received vehicle. The animals were killed after 1, 3, and 6 weeks of experiment. Treatment with mycotoxins resulted in several changes in liver histology and ultrastructure, including: (1) an increase in the thickness of the perilobular connective tissue and its penetration to the lobules in gilts receiving DON and DON + ZEN; (2) an increase in the total microscopic liver score (histology activity index (HAI)) in pigs receiving DON and DON + ZEN; (3) dilatation of hepatic sinusoids in pigs receiving ZEN, DON and DON + ZEN; (4) temporary changes in glycogen content in all experimental groups; (5) an increase in iron accumulation in the hepatocytes of gilts treated with ZEN and DON + ZEN; (6) changes in endoplasmic reticulum organization in the hepatocytes of pigs receiving toxins; (7) changes in morphology of Browicz-Kupffer cells after treatment with ZEN, DON, and DON + ZEN. The results show that low doses of mycotoxins used in the present study, even when applied for a short period, affected liver morphology.

Effects of a Fusarium Toxin-Contaminated Maize Treated with Sodium Sulfite on Male Piglets in the Presence of an LPS-Induced Acute Inflammation

We investigated the effects of feeding sodium sulfite (SoS) treated uncontaminated and Fusarium contaminated maize in a porcine lipopolysaccharide (LPS) challenge model. Eighty piglets (7.59 ± 0.92 kg body weight [BW]) were equally assigned to one of four experimental diets containing 10% maize, either uncontaminated and untreated (CON-, 0.09 mg deoxynivalenol [DON]/kg diet) or uncontaminated and SoS-treated (CON+, wet-preserved with 5 g SoS/kg maize; 0.05 mg DON/kg diet), or prepared with 10% of a Fusarium contaminated maize containing mainly deoxynivalenol (DON), either contaminated and untreated (FUS-, 5.36 mg DON/kg diet), or contaminated and SoS-treated (FUS+, wet-preserved with 5 g SoS/kg maize; 0.83 mg DON/kg diet). At day 42 of experiment, ten pigs of each group were injected intraperitoneally with either 7.5 µg LPS/kg BW or placebo (0.9% NaCl). At 120 min after injection, blood samples were collected to analyse TNF-α, hematological profile, clinical biochemistry as well as the redox status. A significant increase in body temperature and cytokine TNF-α concentration was observed in the LPS-injected piglets. Results for hematology, clinical chemistry and redox status indicate no effects of SoS treatment, with exception of neutrophil counts being significantly more pronounced after feeding the SoS treated FUS maize. In conclusion, SoS treatment of maize did not modulate the LPS-induced acute inflammation.

Time course study of the response to LPS targeting the pig immune gene networks

Background

Stress is a generic term used to describe non-specific responses of the body to all kinds of challenges. A very large variability in the response can be observed across individuals, depending on numerous conditioning factors like genetics, early influences and life history. As a result, there is a wide range of individual vulnerability and resilience to stress, also called robustness. The importance of robustness-related traits in breeding strategies is increasing progressively towards the production of animals with a high level of production under a wide range of climatic conditions and management systems, together with a lower environmental impact and a high level of animal welfare. The present study aims at describing blood transcriptomic, hormonal, and metabolic responses of pigs to a systemic challenge using lipopolysaccharide (LPS). The objective is to analyze the individual variation of the biological responses in relation to the activity of the HPA axis measured by the levels of plasma cortisol after LPS and ACTH in 120 juvenile Large White (LW) pigs. The kinetics of the response was measured with biological variables and whole blood gene expression at 4 time points. A multilevel statistical analysis was used to take into account the longitudinal aspect of the data.

Results

Cortisol level reaches its peak 4 h after LPS injection. The characteristic changes of white blood cell count to LPS were observed, with a decrease of total count, maximal at t=+4 h, and the mirror changes in the respective proportions of lymphocytes and granulocytes. The lymphocytes / granulocytes ratio was maximal at t=+1 h. An integrative statistical approach was used and provided a set of candidate genes for kinetic studies and ongoing complementary studies focused on the LPS-stimulated inflammatory response.

Conclusions

The present study demonstrates the specific biomarkers indicative of an inflammation in swine. Furthermore, these stress responses persist for prolonged periods of time and at significant expression levels, making them good candidate markers for evaluating the efficacy of anti-inflammatory drugs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-4363-5) contains supplementary material, which is available to authorized users.

Risks to human and animal health related to the presence of deoxynivalenol and its acetylated and modified forms in food and feed

Deoxynivalenol (DON) is a mycotoxin primarily produced by Fusarium fungi, occurring predominantly in cereal grains. Following the request of the European Commission, the CONTAM Panel assessed the risk to animal and human health related to DON, 3-acetyl-DON (3-Ac-DON), 15-acetyl-DON (15-Ac-DON) and DON-3-glucoside in food and feed. A total of 27,537, 13,892, 7,270 and 2,266 analytical data for DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside, respectively, in food, feed and unprocessed grains collected from 2007 to 2014 were used. For human exposure, grains and grain-based products were main sources, whereas in farm and companion animals, cereal grains, cereal by-products and forage maize contributed most. DON is rapidly absorbed, distributed, and excreted. Since 3-Ac-DON and 15-Ac-DON are largely deacetylated and DON-3-glucoside cleaved in the intestines the same toxic effects as DON can be expected. The TDI of 1 μg/kg bw per day, that was established for DON based on reduced body weight gain in mice, was therefore used as a group-TDI for the sum of DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside. In order to assess acute human health risk, epidemiological data from mycotoxicoses were assessed and a group-ARfD of 8 μg/kg bw per eating occasion was calculated. Estimates of acute dietary exposures were below this dose and did not raise a health concern in humans. The estimated mean chronic dietary exposure was above the group-TDI in infants, toddlers and other children, and at high exposure also in adolescents and adults, indicating a potential health concern. Based on estimated mean dietary concentrations in ruminants, poultry, rabbits, dogs and cats, most farmed fish species and horses, adverse effects are not expected. At the high dietary concentrations, there is a potential risk for chronic adverse effects in pigs and fish and for acute adverse effects in cats and farmed mink.

Chronic DON exposure and acute LPS challenge: effects on porcine liver morphology and function

The aim of the present study was to examine the role of chronic deoxynivalenol (DON) exposition on the liver morphology and function in combination with pre- and post-hepatic lipopolysaccharide (LPS) stress in young pigs fed for 4 weeks with a DON-contaminated diet (4.59 mg/kg feed). At the end of the experiment, LPS (7.5 μg/kg BW) was administered for 1 h pre-hepatically (Vena portae hepatis) or post-hepatically (Vena jugularis). Liver morphology was macroscopically checked and showed haemorrhage in all LPS groups, significantly higher relative liver weights, accompanied by marked oedema in the gallbladder wall. Histological changes were judged by a modified histology activity index (HAI). Liver HAI score was significantly increased in all LPS groups compared to placebo, primarily due to neutrophil infiltration and haemorrhage. DON feed alone was without effect on the liver HAI. Liver function was characterized by (i) hepatic biochemical markers, (ii) mitochondrial respiration and (iii) Ca²⁺ accumulation capacity of isolated mitochondria. Clinical chemical parameters characterizing liver function were initially (<3 h) slightly influenced by LPS. After 3 h, bilirubin and alkaline phosphatase were increased significantly, in DON-fed, jugular-infused LPS group. Respiration and Ca²⁺ accumulation capacity of isolated liver mitochondria was not impaired by chronic DON exposure, acute LPS challenge or combined treatments. DON-contaminated feed did not change macroscopy and histology of the liver, but modified the function under LPS stress. The different function was not linked to modifications of liver mitochondria.

Current sights for mechanisms of deoxynivalenol-induced hepatotoxicity and prospective views for future scientific research: A mini review

Deoxynivalenol (DON) belongs to the group B trichothecenes, which are the most common mycotoxins in cereal commodities. It is very stable within the temperature range 170-350 °C, showing no reduction in its concentration after 30 min at 170 °C. This chemical property is a very dangerous factor for human and animal health. Liver is also responsible for the detoxification and formation of DON-glucuronide in both human and animals. Some studies already demonstrated that DON could induce liver damage remarkably through DON altering expressions of p53, caspase-3, caspase-7, caspase-8 and Bax in different cell lines. At the same time, other publications illustrated some opposite results. At present, a full and systematic discussion of the hepatic toxicity of DON is still lacking. Therefore, the aim of the present review is to summarize and update the prominent evidence, regarding DON effects on liver tissues and cell lines. Moreover, based on the current studies we outline some of the identified molecule targets or pathways involved in DON-induced hepatotoxicity, and put forward our opinions and suggest an hypothesis for future research. Copyright © 2016 John Wiley & Sons, Ltd.

Does Dietary Deoxynivalenol Modulate the Acute Phase Reaction in Endotoxaemic Pigs?--Lessons from Clinical Signs, White Blood Cell Counts, and TNF-Alpha

We studied the interaction between deoxynivalenol (DON)-feeding and a subsequent pre- and post-hepatic immune stimulus with the hypothesis that the liver differently mediates the acute phase reaction (APR) in pigs. Barrows (n = 44) were divided into a DON-(4.59 mg DON/kg feed) and a control-diet group, surgically equipped with permanent catheters pre- (V. portae hepatis) and post-hepatic (V. jugularis interna) and infused either with 0.9% NaCl or LPS (7.5 µg/kg BW). Thus, combination of diet (CON vs. DON) and infusion (CON vs. LPS, jugular vs. portal) created six groups: CON_CON_jug.-CON_por., CON_CON_jug.-LPS_por., CON_LPS_jug.-CON_por., DON_CON_jug.-CON_por., DON_CON_jug.-LPS_por., DON_LPS_jug.-CON_por.. Blood samples were taken at −30, 15, 30, 45, 60, 75, 90, 120, 150, 180 min relative to infusion and analyzed for leukocytes and TNF-alpha. Concurrently, clinical signs were scored and body temperature measured during the same period. LPS as such induced a dramatic rise in TNF-alpha (p < 0.001), hyperthermia (p < 0.01), and severe leukopenia (p < 0.001). In CON-fed pigs, an earlier return to physiological base levels was observed for the clinical complex, starting at 120 min post infusionem (p < 0.05) and persisting until 180 min. DON_LPS_jug.-CON_por. resulted in a lower temperature rise (p = 0.08) compared to CON_LPS_jug.-CON_por.. In conclusion, APR resulting from a post-hepatic immune stimulus was altered by chronic DON-feeding.

Metabolic and hematological consequences of dietary deoxynivalenol interacting with systemic Escherichia coli lipopolysaccharide

Previous studies have shown that chronic oral deoxynivalenol (DON) exposure modulated Escherichia coli lipopolysaccharide (LPS)-induced systemic inflammation, whereby the liver was suspected to play an important role. Thus, a total of 41 barrows was fed one of two maize-based diets, either a DON-diet (4.59 mg DON/kg feed, n = 19) or a control diet (CON, n = 22). Pigs were equipped with indwelling catheters for pre- or post-hepatic (portal vs. jugular catheter) infusion of either control (0.9% NaCl) or LPS (7.5 µg/kg BW) for 1h and frequent blood sampling. This design yielded six groups: CON_CONjugular‑CONportal, CON_CONjugular‑LPSportal, CON_LPSjugular‑CONportal, DON_CONjugular‑CONportal, DON_CONjugular‑LPSportal and DON_LPSjugular‑CONportal. Blood samples were analyzed for blood gases, electrolytes, glucose, pH, lactate and red hemogram. The red hemogram and electrolytes were not affected by DON and LPS. DON-feeding solely decreased portal glucose uptake (p < 0.05). LPS-decreased partial oxygen pressure (pO₂) overall (p < 0.05), but reduced pCO₂ only in arterial blood, and DON had no effect on either. Irrespective of catheter localization, LPS decreased pH and base-excess (p < 0.01), but increased lactate and anion-gap (p < 0.01), indicating an emerging lactic acidosis. Lactic acidosis was more pronounced in the group DON_LPSjugular-CONportal than in CON-fed counterparts (p < 0.05). DON-feeding aggravated the porcine acid-base balance in response to a subsequent immunostimulus dependent on its exposure site (pre- or post-hepatic).

Effects of oregano on performance and immunmodulating factors in weaned piglets

Many health effects can be attributed to the Mediterranean herb oregano (Origanum vulgare L.) and several studies demonstrated the improving effect on performance, changes in blood count, antibacterial, antifungal and immunmodulating abilities. The majority of these investigations were carried out with processed essential oil, while whole plant material was only used in a few studies. Thus, the aim of the present experiment was to test the effect of increasing proportions of dried oregano in piglet feed on health and performance, with a special focus on immune modulation. A total of 80 male castrated weaned piglets (body weight [BW] 7.9 kg ± 1.0 kg) were used in a feeding experiment lasting 5 weeks. They were assigned to 4 experimental groups: a control diet, and three diets with an oregano supplementation at 2 g, 4 g and 8 g per kg feed, respectively, corresponding to 23.5 mg, 46.9 mg and 93.9 mg carvacrol/kg DM. After 3 weeks, half of each group was challenged with 5 µg lipopolysaccharides (LPS) per kg BW. Blood samples were collected 2 h after LPS stimulation and analysed for T-cell phenotypes, granulocyte activity, clinical-chemistry as well as white and red blood count. The results indicate no effects of oregano on performance. In contrast, oregano altered the lymphocyte proportion and the ratio of CD4(+) and CD8(+) T-cells as well as the triglyceride concentration in the serum of non-stimulated and in LPS-stimulated piglets. In conclusion, whole plant supplementation of oregano to piglet feed altered immune-related parameters, but did not modulate the acute inflammatory response induced by LPS stimulation.

Interactions of deoxynivalenol and lipopolysaccharides on tissue protein synthesis in pigs

Possible interactions between the Fusarium toxin deoxynivalenol and lipopolysaccharides on in vivo protein synthesis were investigated in selected porcine tissues. A total of 36 male castrated pigs (initial weight of 26 kg) were used. 24 pigs were fed a control diet and 12 a Fusarium-contaminated diet (chronic oral deoxynivalenol, 3.1 mg/kg diet) for 37 days. Tissue protein synthesis was measured in pigs fed control diet after intravenous infusion of deoxynivalenol (100 µg/kg live weight/h), lipopolysaccharides (7.5 µg/kg live weight/h) or a combination of both compounds on the day of the measurements, while six pigs from the chronic oral deoxynivalenol group were intravenously treated with lipopolysaccharides (7.5 µg/kg live weight/h). Deoxynivalenol challenge alone failed to alter protein synthesis parameters. Fractional protein synthesis rates were exclusively reduced in liver, spleen and small intestine of lipopolysaccharides-treated pigs. Intravenous deoxynivalenol co-exposure enhanced the impacts of lipopolysaccharides on protein synthesis parameters in the spleen and the small intestine to some extent, while a chronic oral pre-exposure with deoxynivalenol relieved its effects in the spleen. Whether these interactions occur in other tissues and under other study conditions, especially toxin doses and route of entry into the body, needs to be examined further.