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1.
Mycotoxin Res ; 39(4): 367-377, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37423938

RESUMO

Cattle are deemed less susceptible to mycotoxins due to the limited internal exposure resulting from rumen microbiota activity. However, the significant amounts of Fusarium mycotoxins deoxynivalenol (DON) and zearalenone (ZEN) frequently detected in bovine follicular fluid samples suggest that they could affect ovarian function. Both mycotoxins trigger several patterns of cell death and activate the NLRP3 inflammasome in the intestine. In vitro studies have reported a number of adverse effects on bovine oocytes. However, the biological relevance of such findings with regard to realistic concentrations of DON and ZEN in bovine follicular fluid is still not clear. Hence, it is important to better characterize the effects of dietary exposure to DON and ZEN on the bovine ovary. Using bovine primary theca cells, this study investigated the effects of real-life patterns for bovine ovary exposure to DON and ZEN, but also DON metabolite DOM-1, on cell death and NLRP3 inflammasome activation. Exposure to DON starting from 0.1 µM significantly decreased theca cell viability. The kinetics of phosphatidylserine translocation and loss of membrane integrity showed that ZEN and DON, but not DOM-1, induce an apoptotic phenotype. qPCR analysis of the expression of NLRP3, PYCARD, IL-1ß, IL-18, and GSDMD in primary theca cells at concentrations of mycotoxin previously reported in cow follicular fluid clearly indicated that DON and DOM-1 individually and in mixture, but not ZEN, activate NLRP3 inflammasome. Altogether, these results suggest that real-life dietary exposure of cattle to DON may induce inflammatory disorders in the ovary.


Assuntos
Fusarium , Micotoxinas , Zearalenona , Feminino , Bovinos , Animais , Zearalenona/análise , Fusarium/metabolismo , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Células Tecais/química , Células Tecais/metabolismo , Micotoxinas/metabolismo , Apoptose
2.
Mol Nutr Food Res ; 65(23): e2100191, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34626057

RESUMO

INTRODUCTION: The food contamination by mycotoxins is of increasing public health concerns. Deoxynivalenol (DON), a mycotoxin contaminating cereals, has been associated with the exacerbation of inflammatory bowel diseases (IBD), thereby raising the question of its role in the development of IBD. Moreover, the effect of DON on the colon is poorly described. METHODS AND RESULTS: Wistar rats exposed (1-4 weeks) to low doses of DON (2 or 9 mg kg-1 feed) show microscopic alterations of colonic tissue (dilated lymphatic vessels, luminal debris, and cubic and flattened enterocytes). Ingestion of DON also alters colonic functions by increasing paracellular permeability while reducing the expression of the tight junction proteins and increased apoptosis in colonic tissue. Pro-apoptotic factors Bax/Bak, cytochrome C, and caspase 9 are upregulated, whereas expression of anti-apoptotic protein Bcl2 tends to decrease for the mitochondrial pathway. An increased expression of FasR and caspase-8 is observed for the extrinsic pathway. An increase in the pro-inflammatory markers TNFα, IL-17, and myeloperoxidase is also observed. CONCLUSION: These results indicate that the dietary exposure to low levels of DON in food targets the colon inducing a health-threatening breakdown of the colonic barrier, highlighting oral exposure to DON as a potential risk factor in triggering IBD.


Assuntos
Exposição Dietética , Mucosa Intestinal , Animais , Colo , Contaminação de Alimentos , Mucosa Intestinal/metabolismo , Ratos , Ratos Wistar , Receptores de Morte Celular , Tricotecenos
3.
Metabolites ; 11(6)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205708

RESUMO

The effects of low doses of toxicants are often subtle and information extracted from metabolomic data alone may not always be sufficient. As end products of enzymatic reactions, metabolites represent the final phenotypic expression of an organism and can also reflect gene expression changes caused by this exposure. Therefore, the integration of metabolomic and transcriptomic data could improve the extracted biological knowledge on these toxicants induced disruptions. In the present study, we applied statistical integration tools to metabolomic and transcriptomic data obtained from jejunal explants of pigs exposed to the food contaminant, deoxynivalenol (DON). Canonical correlation analysis (CCA) and self-organizing map (SOM) were compared for the identification of correlated transcriptomic and metabolomic features, and O2-PLS was used to model the relationship between exposure and selected features. The integration of both 'omics data increased the number of discriminant metabolites discovered (39) by about 10 times compared to the analysis of the metabolomic dataset alone (3). Besides the disturbance of energy metabolism previously reported, assessing correlations between both functional levels revealed several other types of damage linked to the intestinal exposure to DON, including the alteration of protein synthesis, oxidative stress, and inflammasome activation. This confirms the added value of integration to enrich the biological knowledge extracted from metabolomics.

4.
Mutagenesis ; 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32809012

RESUMO

Humans are exposed to multiple exogenous substances, notably through food consumption. Many of these compounds are suspected to impact human health, and their combination could exacerbate their harmful effects. We previously observed in human cells that, among the six most prevalent food contaminant complex mixtures identified in the French diet, synergistic interactions between component appeared in two mixtures compared with the response with the chemicals alone. In the present study, we demonstrated in human cells that these properties are driven only by two heavy metals in each mixture: tellurium (Te) with cadmium (Cd) and Cd with inorganic arsenic (As), respectively. It appeared that the predicted effects for these binary mixtures using the mathematical model of Chou and Talalay confirmed synergism between these heavy metals. Based on different cell biology experiments (cytotoxicity, genotoxicity, mutagenesis and DNA repair inhibition experiments), a detailed mechanistic analysis of these two mixtures suggests that concomitant induction of oxidative DNA damage and decrease of their repair capacity contribute to the synergistic toxic effect of these chemical mixtures. Overall, these results may have broad implications for the fields of environmental toxicology and chemical mixture risk assessment.

5.
Food Chem Toxicol ; 138: 111222, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32145353

RESUMO

Low-level contamination of food and feed by deoxynivalenol (DON) is unavoidable. We investigated the effects of subclinical treatment with DON, and supplementation with probiotic yeast Saccharomyces cerevisiae boulardii I1079 as a preventive strategy in piglets. Thirty-six animals were randomly assigned to either a control diet, a diet contaminated with DON (3 mg/kg), a diet supplemented with yeast (4 × 109 CFU/kg), or a DON-contaminated diet supplemented with yeast, for four weeks. Plasma and tissue samples were collected for biochemical analysis,1H-NMR untargeted metabolomics, and histology. DON induced no significant modifications in biochemical parameters. However, lesion scores were higher and metabolomics highlighted alterations of amino acid and 2-oxocarboxylic acid metabolism. Administering yeast affected aminoacyl-tRNA synthesis and amino acid and glycerophospholipid metabolism. Yeast supplementation of piglets exposed to DON prevented histological alterations, and partial least square discriminant analysis emphasised similarity between the metabolic profiles of their plasma and that of the control group. The effect on liver metabolome remained marginal, indicating that the toxicity of the mycotoxin was not eliminated. These findings show that the 1H-NMR metabolomics profile is a reliable biomarker to assess subclinical exposure to DON, and that supplementation with S. cerevisiae boulardii increases the resilience of piglets to this mycotoxin.


Assuntos
Dieta , Suplementos Nutricionais/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Probióticos/análise , Espectroscopia de Prótons por Ressonância Magnética/métodos , Aminoácidos/metabolismo , Ração Animal/análise , Animais , Indóis/metabolismo , Intestinos , Jejuno/patologia , Rim/patologia , Metabolismo dos Lipídeos , Fígado/patologia , Masculino , Redes e Vias Metabólicas , Metaboloma , Metabolômica , Micotoxinas/toxicidade , Saccharomyces cerevisiae , Suínos
6.
Environ Int ; 137: 105568, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32106047

RESUMO

Aflatoxin B1 (AFB1) is the most potent carcinogen among mycotoxins. Its biosynthesis involves the formation of versicolorin A (VerA), whose chemical structure shares many features with AFB1. Our data revealed significant levels of VerA in foodstuff from Central Asia and Africa. Given this emerging food risk, it was of prime interest to compare the toxic effects of the two mycotoxins against cells originating from the intestinal tract. We used human colon cell lines (Caco-2, HCT116) to investigate the cytotoxic process induced by the two mycotoxins. Contrary to AFB1, a low dose of VerA (1 µM) disturbed the expression level of thousands of genes (18 002 genes). We show that the cytotoxic effects of low doses of VerA (1-20 µM) were stronger than the same low doses of AFB1 in both Caco-2 and HCT116 cell lines. In Caco-2 cells, VerA induced DNA strand breaks that led to apoptosis and reduced DNA replication of dividing cells, consequently inhibiting cell proliferation. Although VerA was able to induce the p53 signaling pathway in p53 wild-type HCT116 cells, its toxicity process did not mainly rely on p53 expression since similar cytotoxic effects were also observed in HCT116 cells that do not express p53. In conclusion, this study provides evidence of the risk of food contamination by VerA and shed light on its toxicological effect on human colon cells.


Assuntos
Antraquinonas , Intestinos/química , Micotoxinas , Aflatoxina B1 , Antraquinonas/farmacocinética , Antraquinonas/toxicidade , Células CACO-2 , Carcinógenos , Humanos , Micotoxinas/farmacocinética , Micotoxinas/toxicidade
7.
Toxins (Basel) ; 11(3)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871167

RESUMO

The gastrointestinal tract is the first physiological barrier against food contaminants, as well as the first target for these toxicants [...].


Assuntos
Intestinos/efeitos dos fármacos , Micotoxinas/toxicidade , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Mucosa Intestinal/metabolismo , Muco/metabolismo
8.
Toxicon ; 160: 29-37, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30776380

RESUMO

Food and feed commodities are often contaminated by more than one mycotoxin. Among the several combinations that frequently occur, fusariotoxins are often mentioned. The multi-mycotoxins contamination is a serious threat for health. In the present study we investigated the toxic interactions between deoxynivalenol (DON), nivalenol (NIV), and fusarenon-X (FX) in Jurkat T cells by using the MTT assay. The tested mycotoxins alone or in combination had a dose dependent effect on proliferating lymphocytes. According to IC50, it could be classified in decreasing order of toxicity: FX > NIV > DON > DON + FX > NIV + FX > DON + NIV > DON + NIV + FX. The type of mycotoxin interactions was assessed by calculating the combination index (CI) and the dose reduction index (DRI). Our data indicate that an antagonistic effect was strongly observed in binary combination between DON and NIV at higher concentrations and ternary mixtures. Meanwhile, the DON and FX mixtures generated moderate antagonism, while NIV and FX provoked different interactions. The effects of tested mycotoxins on apoptosis were also determined using a FACScan flow cytometer. At IC75, the percentages of apoptotic cells in all treatment groups were significantly different when compared to control group but no significant differences among treatment groups was observed. Taken together, our data suggest that immunotoxicity among multi-mycotoxins contamination cannot be predicted based on individual effects but depends on the mixtures, ratio and/or concentrations in the product, as well as type of target cells.


Assuntos
Tricotecenos/toxicidade , Apoptose/efeitos dos fármacos , Bioensaio/métodos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Citometria de Fluxo , Humanos , Concentração Inibidora 50 , Células Jurkat
9.
Toxins (Basel) ; 10(5)2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29762474

RESUMO

Type B trichothecene mycotoxin deoxynivalenol (DON) is one of the most frequently occurring food contaminants. By inducing trans-activation of a number of pro-inflammatory cytokines and increasing the stability of their mRNA, trichothecene can impair intestinal health. Several yeast products, especially Saccharomyces cerevisiae, have the potential for improving the enteric health of piglets, but little is known about the mechanisms by which the administration of yeast counteracts the DON-induced intestinal alterations. Using a pig jejunum explant model, a whole-transcriptome analysis was performed to decipher the early response of the small intestine to the deleterious effects of DON after administration of S. cerevisiae boulardii strain CNCM I-1079. Compared to the control condition, no differentially expressed gene (DE) was observed after treatment by yeast only. By contrast, 3619 probes-corresponding to 2771 genes-were differentially expressed following exposure to DON, and 32 signaling pathways were identified from the IPA software functional analysis of the set of DE genes. When the intestinal explants were treated with S. cerevisiae boulardii prior to DON exposure, the number of DE genes decreased by half (1718 probes corresponding to 1384 genes). Prototypical inflammation signaling pathways triggered by DON, including NF-κB and p38 MAPK, were reversed, although the yeast demonstrated limited efficacy toward some other pathways. S. cerevisiae boulardii also restored the lipid metabolism signaling pathway, and reversed the down-regulation of the antioxidant action of vitamin C signaling pathway. The latter effect could reduce the burden of DON-induced oxidative stress. Altogether, the results show that S. cerevisiae boulardii reduces the DON-induced alteration of intestinal transcriptome, and point to new mechanisms for the healing of tissue injury by yeast.


Assuntos
Jejuno/efeitos dos fármacos , Saccharomyces cerevisiae , Transcriptoma/efeitos dos fármacos , Tricotecenos/toxicidade , Animais , Antioxidantes , Ácido Ascórbico , Jejuno/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Transdução de Sinais/efeitos dos fármacos , Suínos , Proteínas Quinases p38 Ativadas por Mitógeno/genética
10.
Sci Total Environ ; 622-623: 841-848, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29223910

RESUMO

Cadmium (Cd), a common and widespread toxic heavy metal, and mycotoxins such as deoxynivalenol (DON) are frequent contaminants of the food supply. Most of the data on their toxicity concern their effects when present alone. However, consumers can be exposed to a cocktail of DON and Cd. To improve the understanding of their combined toxicity, the effects of DON and Cd alone or in combination were investigated in different human cell lines from the kidney (HEK-293), intestine (Caco-2), blood (HL-60) and liver (HepG2). Cytotoxicity was assessed through ATP measurement and types of interactions determined by the Isobologram-Combination index method. HEK-293 cells were exposed to increasing doses of DON, Cd and their combination at different ratios (DON/Cd of 2/1; 1/1; 1/2 and 1/8). Regardless of the ratio, the type of interaction observed in HEK-293 cells ranged from moderate antagonism to nearly additive with increasing cytotoxicity. In Caco-2 cells, the interactions ranged from nearly additive to antagonism whatever the ratio. At ratio 1/1, in HL-60 and HepG2 cells, interactions ranged from synergy to antagonism depending on the cytotoxicity level. Using human cells lines, this study indicates that the consequences of combined exposure to environmental and food contaminants are specific to the target organ. Further studies are needed to confirm these data in vivo.


Assuntos
Cádmio/toxicidade , Contaminação de Alimentos , Tricotecenos/toxicidade , Células CACO-2 , Sobrevivência Celular , Células HEK293 , Células HL-60 , Células Hep G2 , Humanos , Micotoxinas , Testes de Toxicidade
11.
Sci Rep ; 7(1): 7530, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28790326

RESUMO

The few data available on fusarenon-X (FX) do not support the derivation of health-based guidance values, although preliminary results suggest higher toxicity than other regulated trichothecenes. Using histo-morphological analysis and whole transcriptome profiling, this study was designed to obtain a global view of the intestinal alterations induced by FX. Deoxynivalenol (DON) served as a benchmark. FX induced more severe histological alterations than DON. Inflammation was the hallmark of the molecular toxicity of both mycotoxins. The benchmark doses for the up-regulation of key inflammatory genes by FX were 4- to 45-fold higher than the previously reported values for DON. The transcriptome analysis revealed that both mycotoxins down-regulated the peroxisome proliferator-activated receptor (PPAR) and liver X receptor - retinoid X receptor (LXR-RXR) signaling pathways that control lipid metabolism. Interestingly, several pathways, including VDR/RXR activation, ephrin receptor signaling, and GNRH signaling, were specific to FX and thus discriminated the transcriptomic fingerprints of the two mycotoxins. These results demonstrate that FX induces more potent intestinal inflammation than DON. Moreover, although the mechanisms of toxicity of both mycotoxins are similar in many ways, this study emphasize specific pathways targeted by each mycotoxin, highlighting the need for specific mechanism-based risk assessments of Fusarium mycotoxins.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Micotoxinas/toxicidade , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Tricotecenos/toxicidade , Animais , Castração , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fusarium/química , Fusarium/patogenicidade , Perfilação da Expressão Gênica , Jejuno/citologia , Jejuno/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Receptores X do Fígado/genética , Receptores X do Fígado/metabolismo , Masculino , Análise em Microsséries , Micotoxinas/isolamento & purificação , Receptores Ativados por Proliferador de Peroxissomo/genética , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Receptores X de Retinoides/genética , Receptores X de Retinoides/metabolismo , Transdução de Sinais/genética , Suínos , Técnicas de Cultura de Tecidos , Tricotecenos/isolamento & purificação
12.
Crit Rev Food Sci Nutr ; 57(16): 3489-3507, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26918653

RESUMO

Mycotoxins are secondary fungal metabolites produced mainly by Aspergillus, Penicillium, and Fusarium. As evidenced by large-scale surveys, humans and animals are simultaneously exposed to several mycotoxins. Simultaneous exposure could result in synergistic, additive or antagonistic effects. However, most toxicity studies addressed the effects of mycotoxins separately. We present the experimental designs and we discuss the conclusions drawn from in vitro experiments exploring toxicological interactions of mycotoxins. We report more than 80 publications related to mycotoxin interactions. The studies explored combinations involving the regulated groups of mycotoxins, especially aflatoxins, ochratoxins, fumonisins, zearalenone and trichothecenes, but also the "emerging" mycotoxins beauvericin and enniatins. Over 50 publications are based on the arithmetic model of additivity. Few studies used the factorial designs or the theoretical biology-based models of additivity. The latter approaches are gaining increased attention. These analyses allow determination of the type of interaction and, optionally, its magnitude. The type of interaction reported for mycotoxin combinations depended on several factors, in particular cell models and the tested dose ranges. However, synergy among Fusarium toxins was highlighted in several studies. This review indicates that well-addressed in vitro studies remain valuable tools for the screening of interactive potential in mycotoxin mixtures.


Assuntos
Contaminação de Alimentos/análise , Micotoxinas/análise , Animais , Fumonisinas , Humanos , Micotoxinas/toxicidade , Ocratoxinas , Tricotecenos
13.
Arch Toxicol ; 91(7): 2677-2687, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27915442

RESUMO

The global incidence of Fusarium head blight and attendant cereal grains multi-contamination by the trichothecene mycotoxins deoxynivalenol (DON) and nivalenol (NIV) are increasing as a possible result of climate change and inadequate agricultural practices. At the molecular level, these mycotoxins bind to the ribosome, activate the mitogen-activated protein kinase and induce a local and systemic inflammation. DON is of public health concern owing to the narrow margin between exposure and tolerable daily intake. The intestinal inflammatory response to DON, NIV and their mixture was analyzed to determine thresholds for their intestinal pro-inflammatory effects and characterize the type and magnitude of their interaction. Fully differentiated three-dimensional porcine jejunal explants were exposed to increasing doses of DON and NIV alone or in combination; the expression levels of IL-1α, IL-1ß, IL-8, IL-17A and IL-22 were measured by RT-PCR. Doses as low as 0.16 µM DON or 0.73 µM NIV significantly increase the intestinal expression levels of the tested inflammation-related genes. These doses are lower than those previously reported for other intestinal toxicity endpoints. The combined pro-inflammatory activity of DON and NIV was synergistic for all the tested genes with combination index value range of 0.23-0.8. Our results indicate that (1) inflammation is a very sensitive endpoint for the intestinal toxicity of the trichothecenes and (2) co-exposure to DON and NIV has a greater inflammatory effect than induced by mycotoxins alone. This synergy should be taken into account considering the frequent co-occurrence of DON and NIV in the diet.


Assuntos
Contaminação de Alimentos , Jejuno/efeitos dos fármacos , Tricotecenos/toxicidade , Animais , Citocinas/genética , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Enterite/induzido quimicamente , Enterite/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Doenças do Jejuno/induzido quimicamente , Doenças do Jejuno/patologia , Jejuno/patologia , Micotoxinas/administração & dosagem , Micotoxinas/toxicidade , Técnicas de Cultura de Órgãos/métodos , Suínos , Testes de Toxicidade/métodos , Tricotecenos/administração & dosagem
14.
Arch Toxicol ; 91(6): 2455-2467, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27913847

RESUMO

Patulin is the main mycotoxin contaminating apples. During the brewing of alcoholic beverages, this mycotoxin is degraded to ascladiol, which is also the last precursor of patulin. The present study aims (1) to characterize the last step of the patulin biosynthetic pathway and (2) to describe the toxicity of ascladiol. A patE deletion mutant was generated in Penicillium expansum. In contrast to the wild strain, this mutant does not produce patulin but accumulates high levels of E-ascladiol with few traces of Z-ascladiol. This confirms that patE encodes the patulin synthase involved in the conversion of E-ascladiol to patulin. After purification, cytotoxicities of patulin and E- and Z-ascladiol were investigated on human cell lines from liver, kidney, intestine, and immune system. Patulin was cytotoxic for these four cell lines in a dose-dependent manner. By contrast, both E- and Z-ascladiol were devoid of cytotoxicity. Microarray analyses on human intestinal cells treated with patulin and E-ascladiol showed that the latter, unlike patulin, did not alter the whole human transcription. These results demonstrate that E- and Z-ascladiol are not toxic and therefore patulin detoxification strategies leading to the accumulation of ascladiol are good approaches to limit the patulin risk.


Assuntos
Furanos/toxicidade , Patulina/biossíntese , Patulina/toxicidade , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Furanos/metabolismo , Deleção de Genes , Genes Fúngicos , Células HEK293 , Células HL-60 , Células Hep G2 , Humanos , Isomerismo , Especificidade de Órgãos , Penicillium/genética , Penicillium/metabolismo
15.
Arch Toxicol ; 90(12): 2931-2957, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27663890

RESUMO

Mycotoxins are the most frequently occurring natural contaminants in human and animal diet. Among them, deoxynivalenol (DON), produced by Fusarium, is one of the most prevalent and thus represents an important health risk. Recent detection methods revealed new mycotoxins and new molecules derivated from the "native" mycotoxins. The main derivates of DON are the acetylated forms produced by the fungi (3- and 15-acetyl-DON), the biologically "modified" forms produced by the plant (deoxynivalenol-3-ß-D-glucopyranoside), or after bacteria transformation (de-epoxy DON, 3-epi-DON and 3-keto-DON) as well as the chemically "modified" forms (norDON A-C and DON-sulfonates). High proportions of acetylated and modified forms of DON co-occur with DON, increasing the exposure and the health risk. DON and its acetylated and modified forms are rapidly absorbed following ingestion. At the molecular level, DON binds to the ribosome, induces a ribotoxic stress leading to the activation of MAP kinases, cellular cell-cycle arrest and apoptosis. The toxic effects of DON include emesis and anorexia, alteration of intestinal and immune functions, reduced absorption of the nutrients as well as increased susceptibility to infection and chronic diseases. In contrast to DON, very little information exists concerning the acetylated and modified forms; some can be converted back to DON, their ability to bind to the ribosome and to induce cellular effects varies according to the toxin. Except for the acetylated forms, their toxicity and impact on human and animal health are poorly documented.


Assuntos
Carcinógenos Ambientais/toxicidade , Tricotecenos/toxicidade , Acetilação , Ração Animal/efeitos adversos , Ração Animal/análise , Ração Animal/microbiologia , Animais , Disponibilidade Biológica , Biotransformação , Carcinógenos Ambientais/química , Carcinógenos Ambientais/metabolismo , Contaminação de Alimentos/prevenção & controle , Fusarium/metabolismo , Glucosídeos/química , Glucosídeos/metabolismo , Glucosídeos/toxicidade , Humanos , Absorção Intestinal , Conformação Molecular , Eliminação Renal , Distribuição Tecidual , Toxicocinética , Tricotecenos/química , Tricotecenos/metabolismo
16.
Porcine Health Manag ; 2: 21, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28405447

RESUMO

Mycotoxins are secondary metabolites of fungi that grow on a variety of substrates. Due to their high consumption of cereals and their sensitivity, pigs are highly impacted by the presence of mycotoxins. At the European level, regulations and recommendations exist for several mycotoxins in pig feed. Among these toxins, fumonisin B1 (FB1), and deoxynivalenol (DON) have a great impact on the intestine and the immune system. Indeed, the intestine is the first barrier to food contaminants and can be exposed to high concentrations of mycotoxins upon ingestion of contaminated feed. FB1 and DON alter the intestinal barrier, impair the immune response, reduce feed intake and weight gain. Their presence in feed increases the translocation of bacteria; mycotoxins can also impair the immune response and enhance the susceptibility to infectious diseases. In conclusion, because of their effect on the intestine, FB1 and DON are a major threat to pig health, welfare and performance.

17.
Anim Nutr ; 2(2): 63-68, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29767037

RESUMO

Mycotoxins are fungal secondary metabolites detected in many agricultural commodities, especially cereals. Due to their high consumption of cereals, pigs are exposed to these toxins. In the European Union, regulations and/or recommendations exist in pig feed for aflatoxins, ochratoxin A, fumonisins, zearalenone, and trichothecenes, deoxynivalenol and T-2 toxin. These mycotoxins have different toxic effects, but they all target the immune system. They have immunostimulatory or immunosuppressive effects depending on the toxin, the concentration and the parameter investigated. The immune system is primarily responsible for defense against invading organisms. The consequences of the ingestion of mycotoxin-contaminated feed are an increased susceptibility to infectious diseases, a reactivation of chronic infection and a decreased vaccine efficacy. In this review we summarized the data available on the effect of mycotoxins on the immune system and the consequences for pig health.

18.
Toxins (Basel) ; 7(6): 1945-61, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26035490

RESUMO

The mycotoxins deoxynivalenol (DON) and nivalenol (NIV), worldwide cereal contaminants, raise concerns for animal and human gut health, following contaminated food or feed ingestion. The impact of DON and NIV on intestinal mucosa was investigated after acute exposure, in vitro and in vivo. The histological changes induced by DON and NIV were analyzed after four-hour exposure on pig jejunum explants and loops, two alternative models. On explants, dose-dependent increases in the histological changes were induced by DON and NIV, with a two-fold increase in lesion severity at 10 µM NIV. On loops, NIV had a greater impact on the mucosa than DON. The overall proliferative cells showed 30% and 13% decrease after NIV and DON exposure, respectively, and NIV increased the proliferative index of crypt enterocytes. NIV also increased apoptosis at the top of villi and reduced by almost half the proliferative/apoptotic cell ratio. Lamina propria cells (mainly immune cells) were more sensitive than enterocytes (epithelial cells) to apoptosis induced by NIV. Our results demonstrate a greater impact of NIV than DON on the intestinal mucosa, both in vitro and in vivo, and highlight the need of a specific hazard characterization for NIV risk assessment.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Tricotecenos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Enterócitos/efeitos dos fármacos , Enterócitos/patologia , Feminino , Técnicas In Vitro , Mucosa Intestinal/patologia , Jejuno/patologia , Reprodutibilidade dos Testes , Suínos
19.
Arch Toxicol ; 89(8): 1337-46, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25033990

RESUMO

In case of mycotoxin contaminations, food and feedstuff are usually contaminated by more than one toxin. However toxicological data concerning the effects of mycotoxin combinations are sparse. The intestinal epithelium is the first barrier against food contaminants and this constantly renewing organ is particularly sensitive to mycotoxins. The aim of this study was to investigate the effects of deoxynivalenol (DON) and four other type B trichothecenes (TCTB), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), nivalenol (NIV) and fusarenon-X (FX) alone or in combination on intestinal epithelial cells. Proliferating, non-transformed IPEC-1 cells were exposed to increasing doses of TCTB, alone or in binary mixtures and mycotoxin-induced cytotoxicity was measured with MTT test. The toxicological interactions were assessed using the isobologram-Combination index method. The five tested mycotoxins and their mixtures had a dose-dependent effect on the proliferating enterocytes. DON-NIV, DON-15-ADON and 15-ADON-3-ADON combinations were synergistic, with magnitude of synergy for 10 % cytotoxicity ranging from 2 to 7. The association between DON and 3-ADON also demonstrated a synergy but only at high doses, at lower doses antagonism was noted. Additivity was observed between NIV and FX, and antagonism between DON and FX. These results indicate that the simultaneous presence of mycotoxins in food commodities and diet may be more toxic than predicted from the mycotoxins alone. This synergy should be taken into account considering the frequent co-occurrence of TCTB in the diet.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Tricotecenos/toxicidade , Animais , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Mucosa Intestinal/embriologia , Mucosa Intestinal/patologia , Suínos/embriologia , Tricotecenos/administração & dosagem , Tricotecenos/química
20.
Toxicol Appl Pharmacol ; 272(1): 191-8, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23735874

RESUMO

Deoxynivalenol (DON) is the most prevalent trichothecene mycotoxin in crops in Europe and North America. DON is often present with other type B trichothecenes such as 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), nivalenol (NIV) and fusarenon-X (FX). Although the cytotoxicity of individual mycotoxins has been widely studied, data on the toxicity of mycotoxin mixtures are limited. The aim of this study was to assess interactions caused by co-exposure to Type B trichothecenes on intestinal epithelial cells. Proliferating Caco-2 cells were exposed to increasing doses of Type B trichothecenes, alone or in binary or ternary mixtures. The MTT test and neutral red uptake, respectively linked to mitochondrial and lysosomal functions, were used to measure intestinal epithelial cytotoxicity. The five tested mycotoxins had a dose-dependent effect on proliferating enterocytes and could be classified in increasing order of toxicity: 3-ADON<15-ADON≈DON

Assuntos
Células Epiteliais/efeitos dos fármacos , Mucosa Intestinal/citologia , Mucosa Intestinal/efeitos dos fármacos , Micotoxinas/toxicidade , Tricotecenos/toxicidade , Algoritmos , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Corantes , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Sais de Tetrazólio , Tiazóis
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