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The systemic effects of the Fusarium toxin deoxynivalenol (DON) and of bacterial lipopolysaccharides (LPS) were studied in male castrated pigs (40.4 ± 3.7 kg) infused intravenously with either DON or LPS alone (100 μg DON/kg/h, 7.5 μg/LPS/kg/h), or together (100 μg DON plus 7.5 μg/LPS/kg/h). The Control group received a saline infusion (n=6/treatment, 24h observation period). An additional DON infusion did not exacerbate the clinical signs observed in LPS-infused pigs. For example, rectal temperature climaxed after 4h (40.4 ± 0.2°C) and 5h (40.1 ± 0.3°C), in the LPS and LPS+DON group, respectively. Saline and DON alone did not induce an acute phase reaction as indicated by unaltered plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) while LPS caused a significant rise of both cytokines. TNF-alpha plasma peak concentrations were significantly higher in the LPS compared to the DON+LPS group (94.3 ± 17.2 ng/mL vs. 79.2 ± 15.7 ng/mL) while IL-6 climaxed earlier in the latter group (3h p.i. vs. 2h p.i.). From the tested clinical-chemical plasma characteristics the total bilirubin concentration and the ASAT activity were strongly elevated by the LPS infusion and additionally increased and decreased by DON, respectively. In conclusion, the LPS-induced effects were only marginally modified by DON., (Copyright © 2013. Published by Elsevier Ireland Ltd.)

Lipopolysaccharides (LPS), a cell wall component of gram-negative bacteria, and deoxynivalenol (DON), a prevalent Fusarium-derived contaminant of cereal grains, are each reported to have detrimental effects on the liver. A potentiating toxic effect of the combined exposure was reported previously in a mouse model and hepatocytes in vitro, but not in swine as the most DON-susceptible species. Thus, pigs were fed either a control diet (CON) or a Fusarium contaminated diet (DON, 3.1mg DON/kg diet) for 37 days. At day 37 control pigs were infused for 1h either with physiological saline (CON&#95;CON), 100μg/kg BW DON (CON&#95;DON), 7.5μg/kg BW LPS (CON&#95;LPS), or both toxins (CON&#95;DON/LPS) and Fusarium-pigs with saline (DON&#95;CON) or 7.5μg/kg BW LPS (DON&#95;LPS). Blood samples were taken before and after infusion (-30, +30, +60, +120, and +180min) for clinical blood chemistry. Pigs were sacrificed at +195min and liver histopathology was performed. LPS resulted in higher relative liver weight (p<0.05), portal, periportal and acinar inflammation (p<0.05), haemorrhage (p<0.01) and pathological bilirubin levels (CON&#95;CON 1.0μmol/L vs. CON&#95;LPS 5.4μmol/L, CON&#95;DON/LPS 8.3μmol/L; p<0.001). DON feeding alleviated effects of LPS infusion on histopathology and blood chemistry to control levels, whereas DON infusion alone had no impact., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Rare earth elements (REE) are possible performance enhancers in animal production, but little is known about their effects on ruminants. Therefore a feeding trial was conducted with 40 fattening bulls who received 0, 100, 200 or 300mg REE-citrate/kg dry matter (DM), containing 34.30% La, 58.09% Ce and 7.61% other REE. DM intake was measured daily and live weight weekly. Ex vivo ConcanavalinA (ConA)-stimulated cell proliferation of peripheral blood mononuclear cells (PBMC) was tested by MTT and alamar blue (AB) assay. Serum was analysed for clinical chemical parameters, ion (Mg, Ca and P) and REE concentrations. The effects of LaCl(3), CeCl(3), NdCl(3) and YCl(3) on ConA-stimulated proliferation of PBMC were tested in vitro, using MTT and AB assay. REE-citrate supplementation did affect DM intake, but not live weight gain, clinical chemical parameters, and ion concentrations significantly. In REE-300 group ex vivo proliferation of PBMC was significantly increased. In vitro ConA-stimulated proliferation decreased with rising REE-chloride concentrations. At least at the highest tested concentration (approximately 290μM) the inhibition reached significance. Proliferation of non-stimulated PBMC was not affected dose-dependently. REE affect the proliferation of PBMC, thus an effect on the bovine immune system is possible. However, the great differences in effective doses in vitro and ex vivo (serum REE concentrations) might explain the different results from the experiments., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

The Fusarium derived mycotoxin deoxynivalenol (DON) is frequently found in cereals used for human and animal nutrition. We studied effects of DON in non-transformed, non-carcinoma, polarized epithelial cells of porcine small intestinal origin (IPEC-1 and IPEC-J2) in a low (200 ng/mL) and a high (2000 ng/mL) concentration. Application of high DON concentrations showed significant toxic effects as indicated by a reduction in cell number, in cellular reduction capacity measured by MTT assay, reduced uptake of neutral red (NR) and a decrease in cell proliferation. High dose toxicity was accompanied by disintegration of tight junction protein ZO-1 and increase of cell cycle phase G2/M. Activation of caspase 3 was found as an early event in the high DON concentration with an initial maximum after 6-8 h. In contrast, application of 200 ng/mL DON exhibited a response pattern distinct from the high dose DON toxicity. The cell cycle, ZO-1 expression and distribution as well as caspase 3 activation were not changed. BrdU incorporation was significantly increased after 72 h incubation with 200 ng/mL DON and NR uptake was only transiently reduced after 24 h. Low dose effects of DON on intestinal epithelial cells were triggered by mechanisms different from those responsible for the high dose toxicity., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

The effects of deoxynivalenol (DON) on the mRNA expression of cytokines and inflammation-related genes, as well as the cytokine secretion of porcine hepatocytes and Kupffer cell enriched hepatocyte cultures (co-cultures), were investigated in the absence or presence of LPS. DON and LPS acted in a synergistic manner with regard to a significantly increased mRNA expression of TNF-alpha in hepatocytes exposed to 500 nM or 2000 nM DON, or non-significant increase in co-cultures after 3h of exposure. TNF-alpha supernatant concentrations were increased due to LPS but did not reflect the synergistic effects with DON as observed at mRNA level. IL-6 mRNA in hepatocyte cultures at 6h paralleled the TNF-alpha supernatant pattern at this time point. In co-cultures and hepatocytes, a DON dose dependent induction of IL-6 mRNA was detected in cells not exposed to LPS. Supernatant concentrations of LPS-induced IL-6 were significantly decreased by 2000 nM DON in both types of cell cultures. Also the mRNA expression of the anti-inflammatory IL-10 was increased by DON to various degrees depending on DON-dose, stimulation with LPS and time point of measurement. After 6h, expression of iNOS was only induced by 2000 nM DON, but not in LPS treated cells. Even if mRNA induction was not paralleled by related supernatant concentrations of TNF-alpha, IL-6 and IL-10 under the conditions of the present investigations, it was clearly demonstrated that DON has the potential to provoke and modulate immunological reactions of porcine liver cells.

The cytotoxicity of deoxynivalenol (DON), effects on protein synthesis and albumin secretion was investigated in porcine hepatocytes and Kupffer cell-enriched hepatocyte cultures (co-cultures) in the presence and absence of lipopolysaccharides (LPS). Up to 16microM DON did not reduce the metabolic activity of hepatocytes. Lysosomal activity reacted more sensitively as neutral red uptake was decreased starting at 2 or 4microM DON irrespective of LPS exposure. The synthesis of secreted proteins was reduced to 31% and 42%, and of cellular proteins to 47% and 39%, in the absence and presence of LPS, respectively, when hepatocytes were exposed to 2microM DON. Reduced albumin secretion in response to DON was already observed after 3h in hepatocytes as well as co-cultures while LPS-mediated decrease was not evident until 24h, when interactions between DON and LPS resulted from a diminishing difference between LPS stimulated and non-stimulated cultures with increasing concentrations of DON. All observed effects may be biased by the cells' ability to conjugate DON to glucuronic acid as 54% and 64% of DON administered at 5nM were recovered as conjugates after 48h. Glucuronidation rate, as well as total DON recovery, decreased with increasing concentrations of DON, giving rise to assumptions on the formation of undetected metabolites.

The cytotoxicity of deoxynivalenol (DON) as well as the induction of cytokines and related genes was investigated in porcine pulmonary alveolar macrophages (PAM) in absence or presence of lipopolysaccharides (LPS). IC(20) values were 1.1, 0.4 and 1.0microM DON in the MTT, neutral red and alamar blue assay, respectively, and did not differ significantly in the presence of LPS. The mRNA expression of tumour necrosis factor (TNF)-alpha peaked at 3h, whereas LPS and DON showed synergistic effects resulting in an approximately 20-fold increase at 500nM DON as compared to untreated controls. The supernatant concentrations of TNF-alpha showed similar synergistic effects. The expression of interleukin (IL)-1beta was significantly induced by DON (except for 12h) and LPS. An induction of the mRNA expression of IL-6 by DON was evident only at 3h, whereas the supernatant concentrations of LPS stimulated PAM incubated with 500nM DON were significantly decreased at most time points. Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression did not seem to contribute to the effects of DON in porcine macrophages. The results of the present investigation suggest a contribution of cytokines, especially TNF-alpha and IL-1beta, induced by DON in porcine macrophages to the effects observed in vivo.

Experiments were carried out with 16 castrated male pigs (41.5 +/- 2.0 kg) to examine the toxicokinetics of deoxynivalenol (DON) from naturally contaminated wheat (16.6 mg DON/kg) after chronic exposure or one single oral dose (acute). The systemic absorption (bioavailability) of DON was estimated based on the area under the curves (AUC) after oral (chronic or acute) and intravenous application of pure DON (53 microg/kg live weight). Additionally, a balance study was conducted to quantitatively trace the DON metabolism. After intravenous (IV) DON application (n = 5), serum DON concentrations decreased biphasically with terminal elimination half-lives (t(1/2)beta) of between 4.2 and 33.6h. DON was rapidly absorbed following oral exposure and reached maximal plasma concentrations (C(max)) of 21.79 and 15.21 ng DON/ml serum after (t(max)) 88.4 and 99.1 min in the chronic (n = 5) and acute (n = 6) fed group, respectively. Thereafter serum DON levels declined slowly with an elimination half-life (t(1/2)beta) of 6.28 and 5.32 h for both oral groups. The mean bioavailability (F) of DON was 89% for the chronic group and 54% for the acute oral group. DON was highly distributed in all groups, with an apparent volume of distribution (V(d)) higher than the total body water. Glucuronide conjugation of deoxynivalenol was found in serum samples after oral exposure, but not after intravenous application. Dietary DON caused a significant increase in DON concentrations of urine and faeces, whereby the metabolite de-epoxy-DON was found only in the trials with a pre-period of longer than 4 weeks. The total recovery was 66.6 +/- 39.0% and 54.0 +/- 9.7% for the control and the chronic DON groups, respectively, with urine being the main excretory route. In conclusion, orally administered DON was quickly absorbed to an extent of over 50%, highly distributed and only poorly metabolized. Twenty-four hours following oral dosing, DON could not be detected in the serum, except in one chronically fed pig at the level of the detection limit.