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1.
Ecotoxicol Environ Saf ; 279: 116503, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810288

RESUMO

Kashin-Beck disease (KBD) is an endemic, environmentally associated cartilage disease. Previous studies have shown that the environmental suspected pathogenic factors of KBD, T-2 toxin and low selenium, are involved in the regulation of inflammation, oxidative stress and autophagy in some tissues and organs. In cartilage diseases, the level of cellular autophagy determines the fate of the chondrocytes. However, whether autophagy is involved in KBD cartilage lesions, and the role of low selenium and T-2 toxins in KBD cartilage injury and autophagy are still unclear. This work took the classical AMPK/mTOR/ULK1 autophagy regulatory pathway as the entry point to clarify the relationship between the environmental suspected pathogenic factors and chondrocyte autophagy. Transmission electron microscopy was used to observe the autophagy of chondrocytes in KBD patients. qRT-PCR and western blot were used to analyze the expression of AMPK/mTOR/ULK1 pathway and autophagy markers. The rat model of KBD was established by low selenium and T-2 toxin, the autophagy in rat cartilage was detected after 4- and 12-week interventions. Chondrocyte autophagy was found in KBD, and the AMPK/mTOR/ULK1 pathway was down-regulated. In the rat model, the pathway showed an up-regulated trend when low selenium and T-2 toxin, were treated for a short time or low concentration, and autophagy level increased. However, when low selenium and T-2 toxin were treated for a long time or at high concentrations, the pathway showed a down-regulated trend, and the autophagy level was reduced and even defective. In conclusion, in the process of KBD cartilage lesion, chondrocyte autophagy level may increase in the early stage, and decrease in the late stage with the progression of lesion. Low selenium and T-2 toxins may affect autophagy by AMPK/mTOR/ULK1 pathway.


Assuntos
Proteínas Quinases Ativadas por AMP , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Autofagia , Condrócitos , Doença de Kashin-Bek , Selênio , Toxina T-2 , Serina-Treonina Quinases TOR , Toxina T-2/toxicidade , Toxina T-2/análogos & derivados , Autofagia/efeitos dos fármacos , Doença de Kashin-Bek/patologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Masculino , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Ratos , Feminino , Pessoa de Meia-Idade , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Adulto , Peptídeos e Proteínas de Sinalização Intracelular
2.
Arch Toxicol ; 94(11): 3645-3669, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32910237

RESUMO

T-2 toxin is the most toxic trichothecene mycotoxin, and it exerts potent toxic effects, including immunotoxicity, neurotoxicity, and reproductive toxicity. Recently, several novel metabolites, including 3',4'-dihydroxy-T-2 toxin and 4',4'-dihydroxy-T-2 toxin, have been uncovered. The enzymes CYP3A4 and carboxylesterase contribute to T-2 toxin metabolism, with 3'-hydroxy-T-2 toxin and HT-2 toxin as the corresponding primary products. Modified forms of T-2 toxin, including T-2-3-glucoside, exert their immunotoxic effects by signaling through JAK/STAT but not MAPK. T-2-3-glucoside results from hydrolyzation of the corresponding parent mycotoxin and other metabolites by the intestinal microbiota, which leads to enhanced toxicity. Increasing evidence has shown that autophagy, hypoxia-inducible factors, and exosomes are involved in T-2 toxin-induced immunotoxicity. Autophagy promotes the immunosuppression induced by T-2 toxin, and a complex crosstalk between apoptosis and autophagy exists. Very recently, "immune evasion" activity was reported to be associated with this toxin; this activity is initiated inside cells and allows pathogens to escape the host immune response. Moreover, T-2 toxin has the potential to trigger hypoxia in cells, which is related to activation of hypoxia-inducible factor and the release of exosomes, leading to immunotoxicity. Based on the data from a series of human exposure studies, free T-2 toxin, HT-2 toxin, and HT-2-4-glucuronide should be considered human T-2 toxin biomarkers in the urine. The present review focuses on novel findings related to the metabolism, immunotoxicity, and human exposure assessment of T-2 toxin and its modified forms. In particular, the immunotoxicity mechanisms of T-2 toxin and the toxicity mechanism of its modified form, as well as human T-2 toxin biomarkers, are discussed. This work will contribute to an improved understanding of the immunotoxicity mechanism of T-2 toxin and its modified forms.


Assuntos
Exposição Ambiental/análise , Toxina T-2/metabolismo , Toxina T-2/toxicidade , Animais , Apoptose , Autofagia , Biomarcadores , Hipóxia Celular , Humanos , Transdução de Sinais , Toxina T-2/análogos & derivados
3.
Int J Food Sci Nutr ; 71(5): 540-548, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31791183

RESUMO

Fusarium mycotoxins are common contaminants in cereals and often co-occur with plant-derived mycotoxin sugar conjugates. Several of these modified mycotoxins are not degraded in the small intestine and hence carried through to the large intestine where microbial transformation may occur. This study aims to assess the gastrointestinal stability of the trichothecenes HT-2 toxin (HT-2), HT-2-ß-glucoside (HT-2-Glc), diacetoxyscirpenol (DAS), DAS-α-glucoside (DAS-Glc) and fumonisin B1 (FB1), N-(1-deoxy-d-fructos-1-yl) fumonisin-B1 (NDF-FB1). All tested modified mycotoxins were stable under upper gastrointestinal (GI) conditions. In faecal batch culture experiments, HT-2-Glc was hydrolysed efficiently and no further microbial biotransformation of HT-2 was observed. DAS-Glc hydrolysis was slow and DAS was de-acetylated to 15-monoacetoxyscripenol. NDF-FB1 was hydrolysed at the slowest rate and FB1 accumulation varied between donor samples. Our results demonstrate that all tested modified mycotoxins are stable in the upper GI tract and efficiently hydrolysed by human gut microbiota, thus potentially contributing to colonic toxicity. Hence the microbial biotransformation of any novel modified mycotoxins needs to be carefully evaluated.


Assuntos
Grão Comestível/química , Fumonisinas/metabolismo , Fusarium , Microbioma Gastrointestinal , Glucosídeos/metabolismo , Intestino Grosso , Tricotecenos/metabolismo , Adulto , Biotransformação , Feminino , Contaminação de Alimentos , Trânsito Gastrointestinal , Humanos , Hidrólise , Intestino Grosso/metabolismo , Intestino Grosso/microbiologia , Intestino Delgado/metabolismo , Masculino , Micotoxinas Mascaradas/metabolismo , Pessoa de Meia-Idade , Micotoxinas/metabolismo , Poaceae , Toxina T-2/análogos & derivados , Toxina T-2/metabolismo , Trato Gastrointestinal Superior/metabolismo
4.
Anal Bioanal Chem ; 410(8): 2253-2262, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29411083

RESUMO

Mycotoxins produced by different species of fungi may coexist in cereals and feedstuffs, and could be highly toxic for humans and animals. For quantification of multiple mycotoxins in cereals, we developed a paper-based mycotoxin immune-affinity array. First, paper-based microzone arrays were fabricated by photolithography. Then, monoclonal mycotoxin antibodies were added in a copolymerization reaction with a cross-linker to form an immune-affinity monolith on the paper-based microzone array. With use of a competitive immune-response format, paper-based mycotoxin immune-affinity arrays were successfully applied to detect mycotoxins in samples. The detection limits for deoxynivalenol, zearalenone, T-2 toxin, and HT-2 toxin were 62.7, 10.8, 0.36, and 0.23 µg·kg-1, respectively, which meet relevant requirements for these compounds in food. The recovery rates were 81-86% for deoxynivalenol, 89-117% for zearalenone, 79-86% for T-2 toxin, and 78-83% for HT-2 toxin, and showed the paper-based immune-affinity arrays had good reproducibility. In summary, the paper-based mycotoxin immune-affinity array provides a sensitive, rapid, accurate, stable, and convenient platform for detection of multiple mycotoxins in agro-foods. Graphical abstract Paper-based immune-affinity monolithic array. DON deoxynivalenol, HT-2 HT-2 toxin, T-2 T-2 toxin, PEGDA polyethylene glycol diacrylate, ZEN zearalenone.


Assuntos
Anticorpos Imobilizados/química , Grão Comestível/química , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Imunoensaio/métodos , Micotoxinas/análise , Papel , Animais , Desenho de Equipamento , Análise de Alimentos/instrumentação , Humanos , Imunoensaio/instrumentação , Limite de Detecção , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Polimerização , Reprodutibilidade dos Testes , Toxina T-2/análogos & derivados , Toxina T-2/análise , Tricotecenos/análise , Zearalenona/análise
5.
J Dairy Sci ; 101(1): 113-117, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29055539

RESUMO

We surveyed the presence of 22 mycotoxins in 191 Spanish cow milk samples. Mycotoxins could be carried over from diet into animal milk and have toxic effects on human and animal health. The interaction of different mycotoxins may be additive or synergetic. Therefore, surveillance of mycotoxin co-occurrence in milk is recommended. Aflatoxins M1, B1, B2, G1, and G2, ochratoxins A and B, nivalenol, deoxynivalenol, deepoxy-deoxynivalenol, 3- and 15-acetyldeoxynivalenol, diacetoxyscirpenol, neosolaniol, fusarenon X, T-2 and HT-2 toxins, fumonisins B1, B2, and B3, sterigmatocystin, and zearalenone were analyzed. Samples were treated by liquid-liquid extraction with acidified acetonitrile, followed by an acetonitrile-water phase separation using sodium acetate. The analysis was carried out by HPLC coupled to a triple quadrupole mass spectrometer. None of the analyzed mycotoxins had a concentration level higher than their detection limit (0.05-10.1 µg/L). The aflatoxin M1 in the samples never exceeded the level established by the European Union.


Assuntos
Contaminação de Alimentos/análise , Leite/química , Micotoxinas/análise , Aflatoxina B1/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Feminino , Fumonisinas/análise , Limite de Detecção , Ocratoxinas/análise , Espanha , Toxina T-2/análogos & derivados , Toxina T-2/análise , Espectrometria de Massas em Tandem , Tricotecenos/análise , Zearalenona/análise
6.
Ecotoxicol Environ Saf ; 161: 451-458, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29909314

RESUMO

Trichothecene mycotoxins commonly contaminate cereal grains and are often linked to human and animal food poisoning. The rapid onset of anorexia is a common hallmark of trichothecenes-induced toxicity. Although the neurotransmitters 5-hydroxytryptamine (5-HT) and substance P (SP) are known to regulate appetite, it remains unknown whether these two neurotransmitters are involved in type A trichothecenes-induced anorectic response. The goal of this study is to relate plasma 5-HT and SP to anorectic responses induced by type A trichothecenes T-2 toxin (T-2), HT-2 toxin (HT-2), diacetoxyscirpenol (DAS) and neosolaniol (NEO). These four toxins evoked robust anorectic response and secretion of plasma 5-HT and SP at 1 mg/kg bw. Following oral exposure, plasma 5-HT and SP were elevated and all peaked at 2 h for T-2, HT-2, DAS and NEO. Following intraperitoneal (IP) administration, plasma 5-HT and SP were peaked at 6 h, 6 h, 2 h, 2 h and 2 h, 6 h, 2 h, 2 h for T-2, HT-2, DAS and NEO, respectively. Elevations of plasma 5-HT and SP markedly corresponded to anorexia induction by T-2, HT-2, DAS and NEO. Altogether, the results presented herein indicated that 5-HT and SP play contributory roles in anorectic responses induced by T-2, HT-2, DAS and NEO.


Assuntos
Anorexia/induzido quimicamente , Serotonina/sangue , Substância P/sangue , Tricotecenos/toxicidade , Animais , Anorexia/sangue , Depressores do Apetite , Grão Comestível , Feminino , Camundongos , Neurotransmissores , Toxina T-2/análogos & derivados , Toxina T-2/toxicidade
7.
Toxicol Appl Pharmacol ; 335: 49-55, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28964791

RESUMO

The food-borne trichothecene mycotoxins have been documented to cause human and animal food poisoning. Anorexia is a hallmark of the trichothecene mycotoxins-induced adverse effects. Type B trichothecenes have been previously demonstrated to elicit robust anorectic responses, and this response has been directly linked to secretion of the gut satiety hormones cholecystokinin (CCK) and glucagon-like peptide-17-36 amide (GLP-1). However, less is known about the anorectic effects and underlying mechanisms of the type A trichothecenes, including T-2 toxin (T-2), HT-2 toxin (HT-2), diacetoxyscirpenol (DAS), neosolaniol (NEO). The purpose of this study was to relate type A trichothecenes T-2, HT-2, DAS and NEO-induced anorectic response to changes plasma concentrations of CCK and GLP-1. Following both oral gavage and intraperitoneal (IP) administration of 1mg/kg bw T-2, HT-2, DAS and NEO evoked robust anorectic response and secretion of CCK and GLP-1. Elevations of plasma CCK markedly corresponded to anorexia induction by T-2, HT-2, DAS and NEO. Following oral exposure, plasma CCK was peaked at 6h, 6h, 2h, 2h and lasted up to 24h, 24h, > 6h, > 6h for T-2, HT-2, DAS and NEO, respectively. IP exposed to four toxins all induced elevation of CCK with peak point and duration at 6h and >24h, respectively. In contrast to CCK, GLP-1 was moderately elevated by these toxins. Following both oral and IP exposure, T-2 and HT-2 evoked plasma GLP-1 elevation with peak point and duration at 2h and 6h, respectively. Plasma GLP-1 was peaked at 2h and still increased at 6h for IP and oral administration with DAS and NEO, respectively. In conclusion, CCK plays a contributory role in anorexia induction but GLP-1 might play a lesser role in this response.


Assuntos
Anorexia/prevenção & controle , Regulação do Apetite , Comportamento Animal , Colecistocinina/sangue , Comportamento Alimentar , Peptídeo 1 Semelhante ao Glucagon/sangue , Fragmentos de Peptídeos/sangue , Resposta de Saciedade , Toxina T-2/análogos & derivados , Tricotecenos , Animais , Anorexia/sangue , Anorexia/induzido quimicamente , Anorexia/psicologia , Modelos Animais de Doenças , Feminino , Camundongos , Transdução de Sinais , Fatores de Tempo , Regulação para Cima
8.
Anal Bioanal Chem ; 409(21): 5143-5155, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28646297

RESUMO

A fast, easy, and cheap method for the simultaneous determination and quantification of aflatoxins (B1, B2, G1, G2), T-2 and HT-2 toxins, and fumonisins (B1, B2) in cereal-derived products was developed. This method involved a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction coupled with liquid chromatography-tandem mass spectrometry. The method validation was performed by analyzing samples spiked at four levels, and the recoveries ranged from 83.6 to 102.9%, whereas the maximum values of repeatability and within-laboratory reproducibility were 14.3 and 15.7% following the performance criteria set by the European legislation. The method was then applied for the analysis of 21 cereal-derived products purchased on the Italian market, which were correctly packaged and labeled as intended for human consumption. The co-occurrence of more than one mycotoxin in the analyzed samples could represent a risk for consumers, and the described method could be a valid alternative for their simultaneous detection in the framework of official control. Graphical Abstract ᅟ.


Assuntos
Cromatografia Líquida/métodos , Grão Comestível/química , Fumonisinas/análise , Micotoxinas/análise , Toxina T-2/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Padrões de Referência , Reprodutibilidade dos Testes , Toxina T-2/análise
9.
Biomed Environ Sci ; 30(11): 851-854, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29216964

RESUMO

Twelve healthy rats were divided into the T-2 toxin group receiving gavage of 1 mg/kg T-2 toxin and the control group receiving gavage of normal saline. Total relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system (thighbone, knee joints, and costal cartilage) were significantly higher than those in the heart, liver, and kidneys (P < 0.05). The relative concentrations of T-2 toxin and HT-2 toxin in the skeletal system (thighbone and costal cartilage) were also significantly higher than those in the heart, liver, and kidneys. The rats administered T-2 toxin showed rapid metabolism compared with that in rats administered HT-2 toxin, and the metabolic conversion rates in the different tissues were 68.20%-90.70%.


Assuntos
Osso e Ossos/metabolismo , Toxina T-2/análogos & derivados , Toxina T-2/farmacocinética , Toxina T-2/toxicidade , Animais , Osso e Ossos/química , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Testes de Toxicidade Aguda
10.
J Sci Food Agric ; 97(3): 818-822, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27185279

RESUMO

BACKGROUND: T-2 toxin is a widely distributed mycotoxin in cereals. HT-2 toxin is the major metabolite, which is also a contaminant in cereals. T-2 toxin and HT-2 toxin have been identified as having carcinogenic, hepatotoxic, teratogenic and immunotoxic properties. To reduce the risk of contamination, a rapid, highly sensitive and inexpensive assay for the detection is required. RESULTS: In this study a high-sensitivity chemiluminescent enzyme-linked immunoassay (CL-ELISA) of T-2 toxin and HT-2 toxin was developed. With the help of the chemiluminescent substrate, this protocol showed a highly sensitive character with an IC50 as low as 33.28 ng mL-1 and 27.27 ng mL-1 for T-2 and HT-2, respectively. In addition, this method had no cross-reaction with other structurally related mycotoxins. CONCLUSION: These results indicated that the developed CL-ELISA could be applied for the detection of T-2 toxin and HT-2 toxin in actual samples without complicated steps. © 2016 Society of Chemical Industry.


Assuntos
Carcinógenos Ambientais/análise , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Oryza/química , Sementes/química , Toxina T-2/análogos & derivados , Toxina T-2/análise , Anticorpos Monoclonais/metabolismo , Carcinógenos Ambientais/metabolismo , China , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Limite de Detecção , Medições Luminescentes , Metanol/química , Reprodutibilidade dos Testes , Solubilidade , Solventes/química , Toxina T-2/metabolismo
11.
Anal Chem ; 88(4): 2446-52, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26785138

RESUMO

Here we demonstrate a novel homogeneous one-step immunoassay, utilizing a pair of recombinant antibody antigen-binding fragments (Fab), that is specific for HT-2 toxin and has a positive readout. Advantages over the conventional competitive immunoassay formats such as enzyme-linked immunosorbent assay (ELISA) are the specificity, speed, and simplicity of the assay. Recombinant antibody HT2-10 Fab recognizing both HT-2 and T-2 toxins was developed from a phage display antibody library containing 6 × 10(7) different antibody clones. Specificity of the immunoassay was introduced by an anti-immune complex (IC) antibody binding the primary antibody-HT-2 toxin complex. When the noncompetitive immune complex assay was compared to the traditional competitive assay, an over 10-fold improvement in sensitivity was observed. Although the HT2-10 antibody has 100% cross-reactivity for HT-2 and T-2 toxins, the immune complex assay is highly specific for HT-2 alone. The assay performance with real samples was evaluated using naturally contaminated wheat reference material. The half-maximal effective concentration (EC50) value of the time-resolved fluorescence resonance energy transfer (TR-FRET) assay was 9.6 ng/mL, and the limit of detection (LOD) was 0.38 ng/mL (19 µg/kg). The labeled antibodies can be predried to the assay vials, e.g., microtiter plate wells, and readout is ready in 10 min after the sample application.


Assuntos
Imunoensaio , Toxina T-2/análogos & derivados , Anticorpos Monoclonais/imunologia , Transferência Ressonante de Energia de Fluorescência , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Conformação Molecular , Toxina T-2/análise , Toxina T-2/imunologia
12.
Anal Bioanal Chem ; 408(24): 6823-31, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27475443

RESUMO

Magnetic solid-phase extraction (m-SPE) is a promising sample preparation approach due to its convenience, speed, and simplicity. For the first time, a rapid and reliable m-SPE approach using magnetic multi-walled carbon nanotubes (m-MWCNTs) as the adsorbent was proposed for purification of type A trichothecenes including T-2 toxins (T2), HT-2 toxins (HT-2), diacetoxyscirpenol (DAS), and neosolaniol (NEO) in coix seed. The m-MWCNTs were synthesized by assembling the magnetic nanoparticles (Fe3O4) with MWCNTs by sonication through an aggregation wrap mechanism, and characterized by transmission electron microscope. Several key parameters affecting the performance of the procedure were extensively investigated including extraction solutions, desorption solvents, and m-MWCNT amounts. Under the optimal sample preparation conditions followed by analysis with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), high sensitivity (limit of quantification in the range of 0.3-1.5 µg kg(-1)), good linearity (R (2) > 0.99), satisfactory recovery (73.6-90.6 %), and acceptable precision (≤2.5 %) were obtained. The analytical performance of the developed method has also been successfully evaluated in real coix seed samples. Graphical Abstract Flow chart of determination of type A trichothecenes in coix seed by magnetic solid-phase extraction coupled with ultra-high performance liquid chromatography-tandem mass spectrometry.


Assuntos
Coix/química , Nanotubos de Carbono/química , Sementes/química , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Tricotecenos/análise , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Magnetismo/métodos , Nanotubos de Carbono/ultraestrutura , Toxina T-2/análogos & derivados , Toxina T-2/análise
13.
Arch Toxicol ; 90(4): 997-1007, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25855062

RESUMO

Trichothecene mycotoxins are a family of potent translational inhibitors that are associated with foodborne outbreaks of human and animal gastroenteritis in which vomiting is a clinical hallmark. Deoxynivalenol (DON, vomitoxin) and other Type B trichothecenes have been previously demonstrated to cause emesis in the mink (Neovison vison), and this response has been directly linked to secretion of both the satiety hormone peptide YY3-36 (PYY3-36) and neurotransmitter 5-hydroxytryptamine (5-HT). Here, we characterized the emetic responses in the mink to T-2 toxin (T-2) and HT-2 toxin (HT-2), two highly toxic Type A trichothecenes that contaminate cereals, and further compared these effects to those of emetine, a natural alkaloid that is used medicinally and also well known to block translation and cause vomiting. Following intraperitoneal (IP) and oral exposure, all three agents caused vomiting with evident dose-dependent increases in both duration and number of emetic events as well as decreases in latency to emesis. T-2 and HT-2 doses causing emesis in 50 % of treated animals (ED50s) were 0.05 and 0.02 mg/kg BW following IP and oral administration, respectively, whereas the ED50s for emetine were 2.0 and 1.0 mg/kg BW for IP and oral exposure, respectively. Importantly, oral administration of all three toxins elicited marked elevations in plasma concentrations of PYY3-36 and 5-HT that corresponded to emesis. Taken together, the results suggest that T-2 and HT-2 were much more potent than emetine and that emesis induction by all three translational inhibitors co-occurred with increases in circulating levels of PYY3-36 and 5-HT.


Assuntos
Emetina/farmacologia , Fragmentos de Peptídeos/sangue , Peptídeo YY/sangue , Serotonina/sangue , Toxina T-2/análogos & derivados , Toxina T-2/toxicidade , Vômito/induzido quimicamente , Administração Oral , Animais , Relação Dose-Resposta a Droga , Eméticos/administração & dosagem , Eméticos/farmacologia , Eméticos/toxicidade , Emetina/administração & dosagem , Emetina/toxicidade , Feminino , Vison , Toxina T-2/administração & dosagem
14.
Arch Toxicol ; 90(6): 1495-505, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26138683

RESUMO

T-2 toxin is one of the type A trichothecene mycotoxins that is considered to be the most toxic of the trichothecenes. T-2 toxin has been shown to exert various toxic effects in farm animals and humans, as it induces lesions in the brain and in lymphoid, hematopoietic, and gastrointestinal tissues. HT-2 toxin is the major metabolite of T-2 toxin. There is little information regarding the effects of HT-2 toxin on the female reproductive system, particularly oocyte maturation. Thus, in this study, we investigated the toxic effects of HT-2 on mouse oocyte maturation and its possible mechanisms of action. HT-2 toxin exposure disrupted oocyte maturation, reduced actin expression in both the oocyte cortex and cytoplasm, and disrupted meiotic spindle morphology by reducing p-MAPK protein level. HT-2 toxin exposure also induced oxidative stress and resulted in oocyte apoptosis, as shown by ROS accumulation, increased SOD mRNA level, and the expression of the early apoptosis marker Annexin V and increased caspase-3 and bax mRNA levels. Additionally, HT-2 toxin exposure increased LC3 and ATG12 protein levels and lc3 and atg14 mRNA levels, which indicated that HT-2 toxin induced autophagy in mouse oocytes. We also examined for possible epigenetic modifications. Fluorescence intensity analysis showed that 5mC level increased after HT-2 toxin exposure, whereas H3K9me2 and H3K27me3 levels decreased after HT-2 toxin exposure, which indicated that DNA and histone methylations were altered. Thus, our results indicated that HT-2 toxin exposure reduced mouse oocyte maturation capability by affecting cytoskeletal dynamics, apoptosis/autophagy, oxidative stress, and epigenetic modifications.


Assuntos
Oócitos/efeitos dos fármacos , Fuso Acromático/efeitos dos fármacos , Toxina T-2/análogos & derivados , Actinas/genética , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Técnicas In Vitro , Camundongos Endogâmicos ICR , Microscopia Confocal , Microscopia de Fluorescência , Oócitos/metabolismo , Oócitos/patologia , Estresse Oxidativo/efeitos dos fármacos , Fuso Acromático/metabolismo , Fuso Acromático/patologia , Toxina T-2/toxicidade
15.
Molecules ; 21(4): 449, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27049379

RESUMO

The effect of natural phenolic acids was tested on the growth and production of T-2 and HT-2 toxins by Fusarium langsethiae and F. sporotrichioides, on Mycotoxin Synthetic medium. Plates treated with 0.5 mM of each phenolic acid (caffeic, chlorogenic, ferulic and p-coumaric) and controls without phenolic acid were incubated for 14 days at 25 °C. Fungal biomass of F. langsethiae and F. sporotrichioides was not reduced by the phenolic acids. However, biosynthesis of T-2 toxin by F. langsethiae was significantly reduced by chlorogenic (23.1%) and ferulic (26.5%) acids. Production of T-2 by F. sporotrichioides also decreased with ferulic acid by 23% (p < 0.05). In contrast, p-coumaric acid significantly stimulated the production of T-2 and HT-2 toxins for both strains. A kinetic study of F. langsethiae with 1 mM ferulic acid showed a significant decrease in fungal biomass, whereas T-2 production increased after 10 days of incubation. The study of gene expression in ferulic supplemented cultures of F. langsethiae revealed a significant inhibition for Tri5, Tri6 and Tri12 genes, while for Tri16 the decrease in gene expression was not statistically significant. Overall, results indicated that phenolic acids had a variable effect on fungal growth and mycotoxin production, depending on the strain and the concentration and type of phenolic acid assayed.


Assuntos
Ácidos Cafeicos/farmacologia , Ácido Clorogênico/farmacologia , Ácidos Cumáricos/farmacologia , Hidroxibenzoatos/farmacologia , Ácidos Cafeicos/química , Ácido Clorogênico/química , Ácidos Cumáricos/química , Proteínas Fúngicas/biossíntese , Fusarium/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hidroxibenzoatos/química , Propionatos , Toxina T-2/análogos & derivados , Toxina T-2/antagonistas & inibidores , Toxina T-2/biossíntese
16.
Appl Environ Microbiol ; 81(15): 4885-93, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25979885

RESUMO

Glycosylation plays a central role in plant defense against xenobiotics, including mycotoxins. Glucoconjugates of Fusarium toxins, such as deoxynivalenol-3-O-ß-d-glucoside (DON-3G), often cooccur with their parental toxins in cereal-based food and feed. To date, only limited information exists on the occurrence of glucosylated mycotoxins and their toxicological relevance. Due to a lack of analytical standards and the requirement of high-end analytical instrumentation for their direct determination, hydrolytic cleavage of ß-glucosides followed by analysis of the released parental toxins has been proposed as an indirect determination approach. This study compares the abilities of several fungal and recombinant bacterial ß-glucosidases to hydrolyze the model analyte DON-3G. Furthermore, substrate specificities of two fungal and two bacterial (Lactobacillus brevis and Bifidobacterium adolescentis) glycoside hydrolase family 3 ß-glucosidases were evaluated on a broader range of substrates. The purified recombinant enzyme from B. adolescentis (BaBgl) displayed high flexibility in substrate specificity and exerted the highest hydrolytic activity toward 3-O-ß-d-glucosides of the trichothecenes deoxynivalenol (DON), nivalenol, and HT-2 toxin. A Km of 5.4 mM and a Vmax of 16 µmol min(-1) mg(-1) were determined with DON-3G. Due to low product inhibition (DON and glucose) and sufficient activity in several extracts of cereal matrices, this enzyme has the potential to be used for indirect analyses of trichothecene-ß-glucosides in cereal samples.


Assuntos
Bifidobacterium/enzimologia , Celulases/metabolismo , Fusarium/metabolismo , Glucosídeos/metabolismo , Toxina T-2/análogos & derivados , Tricotecenos/metabolismo , Celulases/química , Celulases/isolamento & purificação , Grão Comestível/química , Hidrólise , Cinética , Levilactobacillus brevis/enzimologia , Micotoxinas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Toxina T-2/metabolismo
17.
Anal Bioanal Chem ; 407(26): 8019-33, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26335000

RESUMO

An extensive study of the metabolism of the type A trichothecene mycotoxins HT-2 toxin and T-2 toxin in barley using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) is reported. A recently developed untargeted approach based on stable isotopic labelling, LC-Orbitrap-MS analysis with fast polarity switching and data processing by MetExtract software was combined with targeted LC-Q-TOF-MS(/MS) analysis for metabolite structure elucidation and quantification. In total, 9 HT-2 toxin and 13 T-2 toxin metabolites plus tentative isomers were detected, which were successfully annotated by calculation of elemental formulas and further LC-HRMS/MS measurements as well as partly identified with authentic standards. As a result, glucosylated forms of the toxins, malonylglucosides, and acetyl and feruloyl conjugates were elucidated. Additionally, time courses of metabolite formation and mass balances were established. For absolute quantification of those compounds for which standards were available, the method was validated by determining apparent recovery, signal suppression, or enhancement and extraction recovery. Most importantly, T-2 toxin was rapidly metabolised to HT-2 toxin and for both parent toxins HT-2 toxin-3-O-ß-glucoside was identified (confirmed by authentic standard) as the main metabolite, which reached its maximum already 1 day after toxin treatment. Graphical Abstract Isotope-assisted untargeted screening of HT-2 toxin and T-2 toxin metabolites in barley.


Assuntos
Fusarium/metabolismo , Hordeum/metabolismo , Hordeum/microbiologia , Toxina T-2/análogos & derivados , Toxina T-2/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos
18.
Anal Bioanal Chem ; 407(11): 2997-3007, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25399074

RESUMO

Trichothecene mycotoxins, with T-2 and HT-2 toxins being the main representatives of the type A subgroup, are naturally and worldwide occurring contaminants frequently found in grain-based food and feed. Due to the high consumption of these products and the potential health risk associated herewith, concerns about the safety and quality of food and feed have increased over the last decades at both governmental and consumer levels. Since it is not possible to avoid their occurrence, tremendous efforts have been performed to identify and monitor mycotoxins in food and feed to make their consumption safe. However, suitable certified reference materials (CRMs) intended for quality assurance and quality control purposes are still lacking for many mycotoxin-matrix combinations. Therefore, in the framework of a European Reference Material (ERM®) project, the first CRM for T-2 and HT-2 toxin in ground oat flakes (ERM®-BC720) was developed according to the requirements of ISO Guide 35. The whole process of ERM®-BC720 development, including sample preparation, homogeneity and stability studies and value assignment, is presented. The assignment of the certified mass fractions was based upon an in-house study using high-performance liquid chromatography isotope-dilution tandem mass spectrometry. Simultaneously, an interlaboratory comparison study involving 24 expert laboratories was conducted in order to support the in-house certification study. The certified values and their corresponding expanded uncertainties (k = 2) for both T-2 and HT-2 toxin in ERM®-BC720, traceable to the international system of units, are (82 ± 4) µg kg(-1) and (81 ± 4) µg kg(-1), respectively.


Assuntos
Avena/química , Cromatografia Líquida de Alta Pressão/normas , Análise de Alimentos/normas , Toxina T-2/análogos & derivados , Toxina T-2/análise , Espectrometria de Massas em Tandem/normas , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Grão Comestível/química , Análise de Alimentos/métodos , Controle de Qualidade , Padrões de Referência , Toxina T-2/normas , Espectrometria de Massas em Tandem/métodos
19.
J Environ Sci Health B ; 50(2): 128-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25587782

RESUMO

Assessment of A-trichothecene mycotoxins (T-2 and HT-2 toxins) effect combined with growth factor IGF-I, and the metabolic hormones leptin and ghrelin on progesterone secretion by rabbit ovarian fragments was studied. Rabbit ovarian fragments were incubated without (control group) or with T-2/HT-2 toxin, or their combinations with insulin-like growth factor I (IGF-I), leptin or ghrelin at various concentrations for 24 h. Secretion of progesterone was determined by ELISA. First, T-2 toxin and HT-2 toxins at all doses used (0.01, 0.1, 1, 10, and 100 ng mL(-1)) were not shown to be potential regulators of progesterone secretion in rabbit ovarian fragments. Second, T-2 toxin but not HT-2 toxin combined with IGF-I was shown to be potential regulator of progesterone secretion in rabbit ovarian fragments. T-2 toxin at all doses used (0.01; 0.1; 1; 10; and 100 ng mL(-1)) combined with IGF-I (at dose 100 ng mL(-1)) significantly (P < 0.05) decreased progesterone secretion by rabbit ovarian fragments. Third, T-2 toxin and HT-2 toxin at all doses used in the study (0.01, 0.1, 1, 10, and 100 ng mL(-1)) combined with leptin (at dose 1000 ng mL(-1)) were not shown to be potential regulators of progesterone secretion in rabbit ovarian fragments. Furthermore, T-2 toxin and HT-2 toxin at all doses used in the study (0.01, 0.1, 1, 10, and 100 ng mL(-1)) combined with ghrelin (500 ng mL(-1)) were not shown to be potential regulators of progesterone secretion in rabbit ovarian fragments. Results in this study showed that trichothecene as T-2 toxin combined with IGF-I but not HT-2 toxin was able to decrease progesterone secretion in rabbit ovarian fragments in vitro. Experimental results of T-2 and HT-2 toxins combined with leptin and ghrelin did not confirm ability to modulate progesterone secretion by ovarian fragments in rabbits.


Assuntos
Grelina/farmacologia , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/farmacologia , Leptina/farmacologia , Ovário/efeitos dos fármacos , Progesterona/metabolismo , Toxina T-2/análogos & derivados , Toxina T-2/toxicidade , Animais , Combinação de Medicamentos , Ensaio de Imunoadsorção Enzimática , Feminino , Micotoxinas/toxicidade , Ovário/metabolismo , Coelhos
20.
Artigo em Inglês | MEDLINE | ID: mdl-24345238

RESUMO

The aim of this study was to examine the effect of A-trichothecenes T-2 and HT-2 toxins combined with insulin-like growth factor I (IGF-I) on the release of steroid hormone progesterone (P4) by porcine ovarian granulosa cells (GCs). The cells were incubated without (control) or with treatments of A-trichothecenes T-2 (100 and 1000 ng/mL)/ HT-2 (100 and 1000 ng/mL) combined with IGF-I (1, 10 and 100 ng/mL) for 24 h. Progesterone secretion was determined by RIA. The release of P4 by GCs after addition of T-2 toxin (at 100 ng/mL) combined with IGF-I (at 10 but not at 1 and 100 ng/mL) and HT-2 toxin (at 100 ng/mL) combined with IGF-I (at all doses) was significantly (P < 0.05) inhibited. On the other hand the release of P4 after addition of T-2/ HT-2 toxin (at 1000 ng/mL) combined with IGF-I (at all doses) was significantly (P < 0.05) stimulated. Alone IGF-I addition (at 10, 100 but not at 1 ng/mL) significantly (P < 0.05) stimulated P4 release by GCs. The results of our in vitro study indicate the T-2 and HT-2 toxins combined with IGF-I could modify progesterone secretion by porcine ovarian granulosa cells and potentially regulate process of steroidogenesis in the ovaries. Currently, occurrence of mycotoxins in food and feed is a worldwide problem and therefore study of these toxins as well as their interaction with different substances such as growth factors could be beneficial for better understanding of mechanism of their toxic effects in organism.


Assuntos
Células da Granulosa/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/farmacologia , Progesterona/metabolismo , Toxina T-2/análogos & derivados , Toxina T-2/toxicidade , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Células da Granulosa/metabolismo , Suínos
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