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1.
Nat Commun ; 15(1): 4340, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773142

RESUMO

Macrophage-orchestrated inflammation contributes to multiple diseases including sepsis. However, the underlying mechanisms remain to be defined clearly. Here, we show that macrophage TP53-induced glycolysis and apoptosis regulator (TIGAR) is up-regulated in murine sepsis models. When myeloid Tigar is ablated, sepsis induced by either lipopolysaccharide treatment or cecal ligation puncture in male mice is attenuated via inflammation inhibition. Mechanistic characterizations indicate that TIGAR directly binds to transforming growth factor ß-activated kinase (TAK1) and promotes tumor necrosis factor receptor-associated factor 6-mediated ubiquitination and auto-phosphorylation of TAK1, in which residues 152-161 of TIGAR constitute crucial motif independent of its phosphatase activity. Interference with the binding of TIGAR to TAK1 by 5Z-7-oxozeaenol exhibits therapeutic effects in male murine model of sepsis. These findings demonstrate a non-canonical function of macrophage TIGAR in promoting inflammation, and confer a potential therapeutic target for sepsis by disruption of TIGAR-TAK1 interaction.


Assuntos
Proteínas Reguladoras de Apoptose , Modelos Animais de Doenças , Lipopolissacarídeos , MAP Quinase Quinase Quinases , Macrófagos , Sepse , Animais , Sepse/imunologia , Sepse/tratamento farmacológico , Sepse/metabolismo , MAP Quinase Quinase Quinases/metabolismo , MAP Quinase Quinase Quinases/genética , Masculino , Camundongos , Macrófagos/metabolismo , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/genética , Camundongos Endogâmicos C57BL , Fosforilação , Humanos , Ubiquitinação , Zearalenona/análogos & derivados , Zearalenona/farmacologia , Zearalenona/administração & dosagem , Fator 6 Associado a Receptor de TNF/metabolismo , Fator 6 Associado a Receptor de TNF/genética , Inflamação/metabolismo , Inflamação/patologia , Monoéster Fosfórico Hidrolases/metabolismo , Camundongos Knockout , Lactonas , Resorcinóis
2.
J Adv Res ; 40: 95-107, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36100336

RESUMO

INTRODUCTION: Basic fibroblast growth factor (bFGF) plays a critical role in odontoblast differentiation and dentin matrix deposition, thereby aiding pulpo-dentin repair and regeneration. OBJECTIVES: The purpose of this study was to clarify the effects of bFGF on plasminogen activation factors, TIMP-1), ALP; and SPARC (osteonectin) expression/production of stem cells from apical papilla (SCAP) in vitro; and the involvement of MEK/ERK, p38, Akt, and TAK1 signaling. METHODS: SCAP were exposed to bFGF with/without pretreatment and co-incubation with various signal transduction inhibitors (U0126, SB203580, LY294002, and 5Z-7-oxozeaenol). The expression of FGF receptors (FGFRs), PAI-1, uPA, p-ERK, p-TAK1, and p-p38 was analyzed via immunofluorescent staining. The gene expression and protein secretion of SCAP were determined via real-time PCR and ELISA. ALP activity was evaluated via ALP staining. RESULTS: SCAP expressed FGFR1, 2, 3, and 4. bFGF stimulated the PAI-1, uPA, uPAR, and TIMP-1 mRNA expression (p < 0.05). bFGF induced PAI-1, uPA, and soluble uPAR production (p < 0.05) but suppressed the ALP activity and SPARC production (p < 0.05) of SCAP. bFGF stimulated ERK, TAK1, and p38 phosphorylation of SCAP. U0126 (a MEK/ERK inhibitor) and 5Z-7-oxozeaenol (a TAK1 inhibitor) attenuated the bFGF-induced PAI-1, uPA, uPAR, and TIMP-1 expression and production of SCAP, but SB203580 (a p38 inhibitor) did not. LY294002, SB203580, and 5Z-7oxozeaenol could not reverse the inhibition of ALP activity caused by bFGF. Interestingly, U0126 and 5Z-7-oxozeaenol prevented the bFGF-induced decline of SPARC production (p < 0.05). CONCLUSION: bFGF may regulate fibrinolysis and matrix turnover via modulation of PAI-1, uPA, uPAR, and TIMP-1, but bFGF inhibited the differentiation (ALP, SPARC) of SCAP. These events are mainly regulated by MEK/ERK, p38, and TAK1. Combined use of bFGF and SCAP may facilitate pulpal/root repair and regeneration via regulation of the plasminogen activation system, migration, matrix turnover, and differentiation of SCAP.


Assuntos
Fosfatase Alcalina , Fator 2 de Crescimento de Fibroblastos , Fosfatase Alcalina/metabolismo , Fosfatase Alcalina/farmacologia , Butadienos , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/farmacologia , Lactonas , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/farmacologia , Nitrilas , Osteonectina/metabolismo , Osteonectina/farmacologia , Plasminogênio/metabolismo , Plasminogênio/farmacologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidor 1 de Ativador de Plasminogênio/farmacologia , Resorcinóis , Transdução de Sinais , Células-Tronco/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-1/farmacologia , Zearalenona/administração & dosagem
3.
Sci Rep ; 11(1): 7403, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795755

RESUMO

Colon cancer is one of the leading causes of cancer death worldwide. It is widely believed that environmental factors contribute to colon cancer development. Zearalenone (ZEA) is non-steroidal estrogenic mycotoxin that is widely found in the human diet and animal feeds. Most cancer studies of ZEA focused on estrogen sensitive cancers, while few focused on other types, such as colon cancer; despite the gastrointestinal tract being the first barrier exposed to food contaminants. This study investigated the stimulatory effects of ZEA on colon cancer cell lines and their underlying molecular mechanisms. ZEA promoted anchorage independent cell growth and cell cycle progression through promoting G1-to-S phase transition. Proliferative marker, cyclin D1 and Ki67 were found to be upregulated upon ZEA treatment. G protein-coupled estrogenic receptor 1 (GPER) protein expression was promoted upon ZEA treatment suggesting the involvement of GPER. The growth promoting effect mediated through GPER were suppressed by its antagonist G15. ZEA were found to promote the downstream parallel pathway, MAPK signaling pathway and Hippo pathway effector YAP1. Altogether, our observations suggest a novel mechanism by which ZEA could promote cancer growth and provide a new perspective on the carcinogenicity of ZEA.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Neoplasias do Colo/metabolismo , Estrogênios não Esteroides/administração & dosagem , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Zearalenona/administração & dosagem , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/genética , Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/genética , Fatores de Transcrição/metabolismo , Proteínas de Sinalização YAP
4.
Toxins (Basel) ; 12(3)2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111008

RESUMO

The objective of this study was to determine the effect of long-term (48 days), per os administration of specific zearalenone (ZEN) doses (20 and 40 µg ZEN/kg BW in experimental groups EI and EII, which were equivalent to 200% and 400% of the upper range limit of the no-observed-adverse-effect-level (NOAEL), respectively) on the bioavailability of ZEN and the rate of changes in estradiol and testosterone concentrations in the peripheral blood of pre-pubertal gilts. ZEN and α-ZEL levels were similar until day 28. After day 28, α-ZEL concentrations increased significantly in group EI, whereas a significant rise in ZEN levels was noted in group EII. The presence of estradiol in peripheral blood plasma was not observed until day 20 of the experiment. Spontaneous secretion of estradiol was minimal, and it was determined at very low levels of up to 10 pg/mL in EI and EII groups. Testosterone concentrations ranged from 4 to 9 ng/mL in all groups. A decrease in the concentrations of both analyzed hormones was reported in the last stage of the experiment. The results of the experiment indicate that: (i) The bioavailability of ZEN in peripheral blood has low diagnostic value, (ii) exposure to low doses of ZEN induces minor changes in the concentrations of the analyzed hormones, which could lead to situational supraphysiological hormone levels and changes in endogenous hormonal balance.


Assuntos
Estradiol/sangue , Testosterona/sangue , Zearalenona/administração & dosagem , Zearalenona/farmacocinética , Ração Animal , Animais , Disponibilidade Biológica , Feminino , Maturidade Sexual , Suínos
5.
Toxicology ; 429: 152337, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31760079

RESUMO

Zearalenone (ZEA) contamination of feed affects animal husbandry and the human health. Currently, the molecular mechanism underlying small intestine-related diseases caused by ZEA-induced oxidative stress is not well understood. In this study, we aimed to identify the mechanisms involved in ZEA (0.5-1.5 mg/kg)-induced oxidative stress in the ileum and mesenteric lymph nodes (MLNs) and the role of the Kelch-like erythroid cell-derived protein with CNC homology-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway in post-weaning gilts. Forty post-weaning gilts (Landrace × Yorkshire × Duroc) with an average body weight of 14.01 ± 0.86 kg were randomly allocated to four groups and fed a corn-soybean meal basal diet supplemented with < 0.1, 0.5, 1.0, or 1.5 mg/kg ZEA. The results showed that the activity of total superoxide dismutase and glutathione peroxidase decreased (p < 0.05) linearly and quadratically and that the content of malondialdehyde increased (p < 0.05) quadratically in the ileum and MLNs with increasing ZEA in the diet. Immunohistochemical analysis showed that the expression of Nrf2 and glutathione peroxidase 1 (Gpx1) immunoreactive proteins in the ileum and MLNs were significantly enhanced with increasing ZEA. The relative mRNA and protein expression of Nrf2, Gpx1, quinone oxidoreductase 1 (Nqo1), hemeoxygenase 1 (Ho1), modifier subunit of glutamate-cysteine ligase (Gclm), and catalytic subunit of glutamate-cysteine ligase (Gclc) increased (p < 0.05) linearly and quadratically, and the relative mRNA and protein expression of Keap1 decreased (p < 0.05) linearly and quadratically in the ileum with increasing ZEA concentrations in the diet. Further, the relative mRNA and protein expression of Nrf2 and Gpx1 increased (p < 0.05) linearly and quadratically, and the relative mRNA and protein expression of Nqo1, Ho1, and Gclm decreased (p < 0.05) quadratically in the MLNs as ZEA concentrations increased in the diet. Our results provide valuable genetic information on ZEA-induced oxidative stress in the ileum and MLNs of post-weaning gilts and have elucidated the key regulatory genes involved in the Keap1-Nrf2 signaling pathway. Results indicated that the Keap1-Nrf2 signaling pathway might be a key target to further prevent and treat ZEA-induced injury to the ileum in post-weaning gilts.


Assuntos
Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Zearalenona/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Íleo/metabolismo , Linfonodos/metabolismo , Mesentério/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Suínos , Desmame , Zearalenona/administração & dosagem
6.
Vet Clin Pathol ; 48(2): 328-334, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31102279

RESUMO

BACKGROUND: Zearalenone (ZEN) is a mycoestrogen with a ubiquitous presence in animal feeds, which also has hematotoxic, hepatotoxic, nephrotoxic, and immunotoxic properties. However, there is a paucity of literature that discusses the effects of ZEN on rabbits. OBJECTIVES: The aim of this study was to evaluate the effect of a prolonged, low-level (50 µg ZEN/kg body weight) exposure on the clinicopathologic and redox status analytes of rabbit bucks. METHODS: Ten adult bucks were included in the study. Each underwent a 7-week control period, followed by a 7-week exposure period. Water or ZEN solutions were daily administered orally (0.5 mL) during the control and exposure periods, respectively. Blood samples were collected weekly for Complete Blood Counts, serum biochemical analyte and reactive oxygen metabolite (ROM) measurements. Data were analyzed using a mixed model, and the level of significance was set at a P of <0.05. RESULTS: During the ZEN exposure period, significant increases were noted in the red blood cell distribution width (RDW) and mean platelet volumes (MPVs), as well as in the white blood cell, monocyte, and eosinophil counts. Significant increases were observed in aspartate aminotransferase and total bilirubin, whereas urea, creatinine, glucose, total calcium, sodium, and potassium concentrations were significantly decreased. The ROM concentrations did not differ significantly between the control and ZEN exposure periods. CONCLUSIONS: Under the present experimental conditions, ZEN affected some of the clinicopathologic analytes of adult rabbit bucks; these changes were mostly indicative of mild hepatocellular damage and dysfunction, inflammatory and/or allergic responses, and renal tubular damage. A ZEN dose of 50 µg/kg body weight did not seem to affect the blood redox status of bucks, as evaluated by the ROM concentrations.


Assuntos
Coelhos/sangue , Zearalenona/administração & dosagem , Administração Oral , Ração Animal/análise , Animais , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Peso Corporal , Masculino , Oxirredução/efeitos dos fármacos
7.
Toxicon ; 154: 7-14, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30055260

RESUMO

Globally, food and animal feed contamination with mycotoxins is one of the most important challenges affecting human health. Zearalenone is a non-steroidal mycotoxin with estrogen-like activity that has been reported to induce reproductive dysfunctions including polycystic ovary in women. The aim of this study was to assess the possible impact of prolonged low dose zearalenone (0.1 mg/kg b.w.) exposure to increase the risk of developing polycystic ovary in rats. We found that zearalenone increases the plasma insulin, glucose, testosterone, progesterone and luteinizing hormone levels, while the plasma estradiol level was reduced. Zearalenone also incited tumor necrosis factor-α and the secreted frizzled-related protein-4 expressions. Histological examination showed atresia of follicles in the treated group. It is concluded that zearalenone intoxication intensely manipulates the plasma hormonal factors and the level of gene expressions related to the polycystic ovary in rats, thus increases the risk of its progression.


Assuntos
Síndrome do Ovário Policístico/induzido quimicamente , Zearalenona/toxicidade , Animais , Glicemia/metabolismo , Estradiol/sangue , Estrogênios/sangue , Feminino , Insulina/sangue , Hormônio Luteinizante/sangue , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/patologia , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/patologia , Progesterona/sangue , Proteínas Proto-Oncogênicas/metabolismo , Distribuição Aleatória , Ratos , Testosterona/sangue , Testes de Toxicidade Crônica , Fator de Necrose Tumoral alfa/sangue , Zearalenona/administração & dosagem
8.
Pol J Vet Sci ; 20(3): 513-520, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-29166278

RESUMO

Human and animal diets may contain several non-steroidal oestrogenic compounds which originate either from plants (phytoestrogens) or from fungi that infect plants (mycoestrogens such as zearalenone (ZEN)). Phytoestrogens may compete with ZEN in binding to the oestrogen receptor ß and thereby may counteract the oestrogenic activity of ZEN. Using a modified version of the E-screen assay, plant-derived oestrogenic substances were tested for their proliferative or anti-proliferative effect on oestrogen-dependent MCF-7 cells. The samples were additionally tested for their ability to influence the oestrogenic activity of ZEN (1 µM). Among the individual substances tested, 8-prenylnaringenin had the strongest effect, as cell proliferation was increased by 78% at the lowest concentration (0.23 µM), and by 167% at the highest concentration (29.4 µM). Coumestrol (5.83 µM) increased cell proliferation by 39%, and genistein (370 µM) by 61%, respectively. Xanthohumol and enterolactone did not stimulate cell proliferation significantly. In the co-incubation experiments with ZEN, none of the single substances was able to decrease the oestrogenic activity of ZEN. Only for 8-prenylnaringenin (14.7 and 29.4 µM) was a trend towards an increase in the ZEN-induced cell proliferation up to 72% observed. In conclusion, with the exception of 8-prenylnaringenin, no substantial interaction between phytoestrogens and the mycotoxin ZEN could be detected using a bioassays with MCF-7 cells.


Assuntos
Estrogênios/farmacocinética , Fitoestrógenos/farmacocinética , Zearalenona/farmacocinética , Bioensaio , Proliferação de Células , Interações Medicamentosas , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Estrogênios não Esteroides/administração & dosagem , Estrogênios não Esteroides/farmacocinética , Humanos , Células MCF-7 , Fitoestrógenos/administração & dosagem , Zearalenona/administração & dosagem
9.
J Immunotoxicol ; 14(1): 125-136, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28641471

RESUMO

Zearalenone (ZEA) is a non-steroidal estrogenic mycotoxin produced by Fusarium species. The toxicity of ZEA has been evaluated for reproductive and developmental effects; however, there is little evidence about its acute toxicity or general immunotoxicity. In the present study, immune regulatory functions were investigated in mice that had been exposed to ZEA (5 or 20 mg/kg BW) daily for 14 days. Results showed that sub-populations of CD4+, CD8+ and CD11c+ cells in the spleen and CD4+, CD8+ and F4/80+ cells in the mesenteric lymph nodes (MLN) of ZEA (20 mg/kg)-exposed hosts were decreased compared to those in the control mice. However, CD19+ and CD11c+ cells were increased in the MLN of the ZEA mice and CD4+CD25+Foxp3+ cells were decreased in the spleen and MLN. There were differential changes in the immune cell populations of the small intestine of the ZEA mice as well, depending on small intestine location. In ex vivo experiments, ZEA treatments resulted in increased proliferative capacities of mitogen-induced splenocytes and MLN cells; such changes were paralleled by significant increases in interferon (IFN)-γ production. With regard to serum isotypes, IgM levels were decreased and IgE levels were increased in the 20 mg/kg ZEA-treated mice. Mucosal IgA levels were decreased in the duodenum and vagina of these hosts. Serum analyzes also revealed that tumor necrosis factor (TNF)-α levels were decreased and interleukin (IL)-6 levels increased as a result of ZEA exposures. ZEA treatment also led to increased apoptosis in the spleen and Peyer's patches; these changes were associated with changes in the ratios of Bax:Bcl-2. Following priming with different TLR ligands, ZEA exposure led to differentially modulated TLR signaling and variable production of pro- and anti-inflammatory cytokines in RAW 264.7 macrophage cells. Taken together, these results indicated that ZEA could alter the normal expression/function of different immune system components and this would likely lead to immunomodulation in situ.


Assuntos
Estrogênios não Esteroides/administração & dosagem , Linfonodos/efeitos dos fármacos , Linfócitos/fisiologia , Macrófagos/fisiologia , Micotoxinas/administração & dosagem , Baço/efeitos dos fármacos , Zearalenona/administração & dosagem , Animais , Apoptose , Proliferação de Células , Citocinas/metabolismo , Estrogênios não Esteroides/efeitos adversos , Feminino , Imunoglobulina E/sangue , Imunoglobulina M/sangue , Imunomodulação , Linfonodos/imunologia , Linfócitos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Micotoxinas/efeitos adversos , Células RAW 264.7 , Baço/imunologia , Zearalenona/efeitos adversos
10.
Food Chem Toxicol ; 106(Pt A): 193-201, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28552786

RESUMO

Zearalenone (ZEN) is a well-studied mycotoxin whose potent estrogenic properties have been used by international regulatory bodies to set health-based guidance values for ZEN exposure in grain-based foods from changes in hormonally responsive tissues of juvenile female pigs. The role of metabolism in determining estrogenic responses in vivo is a major uncertainty in inter-species extrapolation to humans and in assessing the potential for added susceptibility in sensitive subpopulations. This study evaluated the metabolism of ZEN and pharmacokinetics in ∼2 month-old female pigs using oral and intravenous dosing. The absolute bioavailability (AUCoral/AUCIV) of receptor-active ZEN aglycone was 1.8 ± 0.80%, consistent with extensive pre-systemic Phase II conjugation. Reductive metabolism to α-zearalenol (α-ZEL) was extensive, with smaller amounts of ß-ZEL. When combined with its higher binding affinity, relative to ZEN and ß-ZEL, α-ZEL was the predominant contributor to total estrogen receptor ligand activity (∼90%) after oral dosing with ZEN. The apparent similarities of reductive and Phase II conjugation metabolism of ZEN between pigs and humans support the use of juvenile female pigs as a sensitive model for risk assessments of estrogenic effects from dietary ZEN.


Assuntos
Zearalenona/farmacocinética , Administração Intravenosa , Administração Oral , Animais , Feminino , Inativação Metabólica , Suínos , Zearalenona/administração & dosagem , Zearalenona/metabolismo
11.
Pharm Biol ; 55(1): 1289-1294, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28274189

RESUMO

CONTEXT: Lasiodiplodan, an exocellular (1→6)-ß-d-glucan of molecular weight >1.4 × 106 Da produced by MMPI strain of Lasiodiplodia theobromae (Pat.) Griffon & Maubl. (Brotyosphaeriaceae) is known to exhibit anti-proliferative activity on breast cancer cells (MCF-7), anticoagulant activity when sulfonylated, and reduction in transaminase activity when administered in rats. OBJECTIVE: The effect of intracerebroventricular (I.C.V) injection of lasiodiplodan on neurotoxicity and behavioural changes induced by d-penicillamine was investigated. MATERIALS AND METHODS: Twenty-four male Wistar rats were initially separated in groups of six and treated with 0.15 µmol/µL of NaCl (Groups Ct and d-Pen) and 0.01 µg/µL of lasiodiplodan (Groups Las and Las + d-Pen). After 15 min, they received 6 µmol/µL of NaCl (Groups Ct and Las) and 2 µmol/µL of d-penicillamine (Groups d-Pen and Las + d-Pen). The animal behavior was observed in an open-field test for 60 min. Twenty-four h later, the animals were sacrificed and histopathological analysis and Thiobarbituric acid reactive substances (TBARS) production measurements were performed. RESULTS: Lasiodiplodan prevented neurotoxicity induced by d-penicillamine significantly reducing the production of TBARS (308%; p < 0.05), and behavioural signs; convulsive and pre-convulsive. No histopathological alterations in the cerebral cortex were observed. DISCUSSION AND CONCLUSION: The reduction of TBARS production and convulsive episodes suggests that the protector effect provided by lasiodiplodan passes thought an antioxidant path, possibly interfering in a cascade of neurochemical events, triggering cell death and convulsive episodes. These results demonstrated that lasiodiplodan can be effective in treating neurotoxicity, and reducing damage triggered by convulsions in neuropathies related to GABAergic system.


Assuntos
Comportamento Animal/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Penicilamina/toxicidade , Zearalenona/análogos & derivados , Animais , Comportamento Animal/fisiologia , Córtex Cerebral/metabolismo , Injeções Intraventriculares , Peroxidação de Lipídeos/fisiologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Zearalenona/administração & dosagem
12.
Food Chem Toxicol ; 103: 18-27, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28223122

RESUMO

To understand the combinatorial toxicity of mycotoxins, we measured the effects of individual, binary and tertiary combinations of Aflatoxin B1 (AFB1), Deoxynivalenol (DON) and Zearalenone (ZEN) on the cell viability and cellular perturbations of HepG2 and RAW 264.7 cells. The nature of mycotoxins interactions was assessed using mathematical modeling (Chou-Talalay). Mechanisms of cytotoxicity were studied using high content screening (HCS) that probed cytotoxicity responses, such as changes in intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), intracellular calcium ([Ca2+]i) flux, and cell membrane damage. Our results showed that individual cytotoxicity of mycotoxins in a decreasing order was DON>AFB1>ZEN. Varying combinations of mycotoxins at differing concentrations showed different types of interactions. Most of the mixtures showed increasing toxic effects-synergism and/or addition while antagonistic effects were observed with combination of AFB1+ZEN. Generally, combination of mycotoxins showed significantly increased intracellular ROS production and [Ca2+]i flux, and decreased MMP in both cell lines, showing that the synergistic and additive effects of mycotoxin combination originate from perturbations of multiple cellular functions. Additionally, this study demonstrated the applicability of HCS for gaining mechanistic understanding on the toxicity of individual as well as combinatorial mycotoxins, and also provided scientific bases for formulating regulatory policies.


Assuntos
Aflatoxina B1/toxicidade , Testes de Toxicidade/métodos , Tricotecenos/toxicidade , Zearalenona/toxicidade , Aflatoxina B1/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Células Hep G2/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Camundongos , Micotoxinas/administração & dosagem , Micotoxinas/toxicidade , Células RAW 264.7/efeitos dos fármacos , Tricotecenos/administração & dosagem , Zearalenona/administração & dosagem
13.
Toxins (Basel) ; 9(1)2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-28067781

RESUMO

Zearalenone (ZEN) is an oestrogenic mycotoxin commonly found in food and feed products and can affect reproduction and development in both humans and animals. This study aimed to determine the toxic effects of ZEN on maternal SD rats and the F1 female offspring. Sixty-four pregnant rats were divided into 4 groups and exposed to feed contaminated with ZEN (0, 5, 10, and 20 mg/kg feed) on gestational days (GDs) 0-21. Compared with the controls, the groups exposed to 10 and 20 mg/kg ZEN showed significantly decreased feed intake and body weight of pregnant rats and/or female offspring. Meanwhile, 20 mg/kg ZEN significantly decreased the birth weight and viability of F1 newborn rats. Moreover, 10 and 20 mg/kg ZEN diets increased follicle-stimulating hormone concentrations but decreased oestradiol in both maternal and F1 adult rats. In the F1 generation, ZEN caused no pathological changes in ovaries and uterus in weaned rats, but significant follicular atresia and a thinning uterine layer were found in F1 female adult rats in the 20 mg/kg ZEN group. These impairments concurred with the inhibited mRNA and protein levels of oestrogen receptor-alpha (Esr1) and 3ß-hydroxysteroid dehydrogenase (HSD) in the adult uterus and/or ovaries. Furthermore, 10 and/or 20 mg/kg ZEN exposure significantly reduced Esr1, gonadotropin-releasing hormone receptor (GnRHr), and ATP binding cassette transporters b1 and c1 (ABCb1 and ABCc1) in the placenta and foetal and weaned F1 brains, and also produced a dose-dependent increase in 3ß-HSD in the placenta. Additionally, 20 mg/kg ZEN significantly upregulated ABCc5 expression in the placenta and ovaries of weaned rats. These results suggested that prenatal ZEN exposure in rats affected maternal and foetal development and may lead to long-term reproductive impairment in F1 adult females.


Assuntos
Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Reprodução/efeitos dos fármacos , Zearalenona/toxicidade , Fatores Etários , Ração Animal , Animais , Peso ao Nascer/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Microbiologia de Alimentos , Regulação da Expressão Gênica no Desenvolvimento , Idade Gestacional , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Medição de Risco , Útero/efeitos dos fármacos , Útero/metabolismo , Útero/patologia , Zearalenona/administração & dosagem
14.
Arch Toxicol ; 91(3): 1447-1460, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27401186

RESUMO

Mycotoxins are toxic secondary metabolites formed by various fungal species that are found as natural contaminants in food. This very heterogeneous group of compounds triggers multiple toxic mechanisms, including endocrine disruptive potential. Current risk assessment of mycotoxins, as for most chemical substances, is based on the effects of single compounds. However, concern on a potential enhancement of risks by interactions of single substances in naturally occurring mixtures has greatly increased recently. In this study, the combinatory effects of three mycoestrogens were investigated in detail. This includes the endocrine disruptors zearalenone (ZEN) and α-zearalenol (α-ZEL) produced by Fusarium fungi and alternariol (AOH), a cytotoxic and estrogenic mycotoxin formed by Alternaria species. For evaluation of effects, estrogen-dependent activation of alkaline phosphatase (AlP) and cell proliferation were tested in the adenocarcinoma cell line Ishikawa. The estrogenic potential varied among the single substances. Half maximum effect concentrations (EC50) for AlP activation were evaluated for α-ZEL, ZEN and AOH as 37 pM, 562 pM and 995 nM, respectively. All three mycotoxins were found to act as partial agonists. The majority of binary combinations, even at very low concentrations in the case of α-ZEL, showed strong synergism in the AlP assay. These potentiating phenomena of mycotoxin mixtures highlight the urgent need to incorporate combinatory effects into future risk assessment, especially when endocrine disruptors are involved. To the best of our knowledge, this study presents the first investigation on synergistic effects of mycoestrogens.


Assuntos
Estrogênios/toxicidade , Lactonas/toxicidade , Zearalenona/toxicidade , Zeranol/análogos & derivados , Fosfatase Alcalina/metabolismo , Alternaria/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Fusarium/química , Humanos , Lactonas/administração & dosagem , Micotoxinas/toxicidade , Testes de Toxicidade/métodos , Zearalenona/administração & dosagem , Zeranol/administração & dosagem , Zeranol/toxicidade
15.
Toxicon ; 120: 175-84, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27530666

RESUMO

The actual health risk from exposure to combined mycotoxins is unknown, and few studies have focused on changes to cellular biological systems (e.g., metabolomics) caused by combined mycotoxic effects. To evaluate the combined mycotoxic effects of deoxynivalenol (DON) and zearalenone (ZEN) on the level of cellular biological systems, gas chromatographic, time-of-flight mass spectroscopy (GC-TOF/MS) of the complete murine macrophage ANA-1 cell metabolome was implemented in this study. Using optimized chromatography and mass spectrometry parameters, the metabolites detected by GC-TOF/MS were identified and processed using multivariate statistical analysis, including principal component analysis (PCA) and orthogonal projection on latent-structures discriminant analysis (OPLS-DA). The metabolite sets were screened for further pathway analysis under rules of t-test (P) value < 0.05, VIP value > 1, and similarity value > 500. The mainly interfered metabolism pathways were categorized into two dominant types: amino acid metabolism and glycometabolism. Four metabolites, palmitic acid, 1-monopalmitin, ribose-5-phosphate and 2-deoxy-D-galactose, occur only under combined "DON + ZEN" treatment, indicating abnormal metabolism in ANA-1 cells. The metabolic state of ANA-1 cells under induction by combined "DON + ZEN" illustrates that DON may inhibit the estrogenic effects of ZEN. Thus, the combined effect of "DON + ZEN" may exacerbate toxicity in the pentose phosphate pathway, while palmitic acid metabolism is likely a new pathway effected by the combination, "DON + ZEN."


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Macrófagos/efeitos dos fármacos , Metabolômica , Tricotecenos/toxicidade , Zearalenona/toxicidade , Animais , Linhagem Celular , Camundongos , Tricotecenos/administração & dosagem , Zearalenona/administração & dosagem
16.
Neuroscience ; 325: 111-23, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27012613

RESUMO

Recently, more and more studies support that inflammation is involved in the pathogenesis of epilepsy. Although TGFß signaling is involved in epileptogenesis, whether TGFß-associated neuroinflammation is sufficient to regulate epilepsy remains unknown to date. Furthermore, tumor necrosis factor-α receptor-associated factor-6 (TRAF6), transforming growth factor beta-activated kinase 1 (TAK1), which are the key elements of TGFß-associated inflammation, is still unclear in epilepsy. Therefore, the present study aimed to explore the role of TRAF6 and TAK1 in pilocarpine-induced epileptic rat model. Firstly, the gene levels and protein expression of TRAF6 and TAK1 were detected in different time points after pilocarpine-induced status epilepticus (SE). 5z-7-oxozeaenol treatment (TAK1 antagonist) was then performed; the changes in TRAF6, TAK1, phosphorylated-TAK1 (P-TAK1), interleukin-1ß (IL-1ß) levels, neuronal survival and apoptosis, and seizure activity were detected. Our results showed that expressions of TRAF6 were increased after SE, reached the peak in 7day, maintained at the high level to 30days, and the TAK1, P-TAK1 levels were increased after SE following time. After 5z-7-oxozeaenol treatment in epileptic rats, TRAF6-TAK1-P-TAK1 signaling protein expressions were reduced, inflammatory cytokine IL-1ß expression was decreased, neuron survival index was improved, the neuron apoptosis index was decreased and seizure durations were alleviated. In conclusion, the expression of TRAF6 and TAK1 are related to the progression of epilepsy. TAK1 might be a potential intervention target for the treatment of epilepsy via neuroprotection.


Assuntos
Córtex Cerebral/metabolismo , Encefalite/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Neurônios/metabolismo , Neuroproteção , Estado Epiléptico/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Modelos Animais de Doenças , Hipocampo/metabolismo , Interleucina-1beta/metabolismo , MAP Quinase Quinase Quinases/antagonistas & inibidores , Masculino , Neurônios/efeitos dos fármacos , Pilocarpina , Ratos , Ratos Sprague-Dawley , Estado Epiléptico/complicações , Zearalenona/administração & dosagem , Zearalenona/análogos & derivados
17.
Tumour Biol ; 37(1): 531-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26227222

RESUMO

Treatment failure in cancer chemotherapy is largely due to the toxic effects of chemotherapeutic agents on normal cells/tissues. The proteasome inhibitor bortezomib has been successfully applied to treat multiple myeloma (MM), but there are some common adverse reactions in the clinic including peripheral neuropathy (PN). The TAK1 selective inhibitor 5Z-7-oxozeaenol has been widely studied in cancer therapy. Here, we investigated the potential synergy of bortezomib and 5Z-7-oxozeaenol in Burkitt's lymphoma (BL) cell lines. Cell viability assay showed that co-treatment of bortezomib at 8 nM, representing a one-eighth concentration for growth arrest, and 5Z-7-oxozeaenol at 2 µM, a dose that exhibited insignificant cytotoxic effects, synergistically induced apoptosis in the cell line Daudi. In parallel with the increasing dose of the bortezomib, and 5Z-7-oxozeaenol at 0.5 µM, lower colony formation efficiencies were seen in the cell line Daudi. Western blotting analysis verified that TAK1 inhibition by 5Z-7-oxozeaenol completely blocked JNK, p38, Erk, IKK, and IκB phosphorylation, which was almost instantly activated by TAK1 both directly or indirectly. Both agents synergistically prevented nuclear translocation of NF-κB, a characteristic of NF-κB inactivation. Moreover, a synergistic effect of bortezomib and 5Z-7-oxozeaenol on Western blotting analysis and flow cytometry was disclosed. Collectively, our results indicated that the proteasome inhibitor bortezomib and the TAK1 inhibitor 5Z-7-oxozeaenol displayed synergy on inhibiting BL cell apoptosis by inhibiting NF-κB activity.


Assuntos
Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Apoptose , Bortezomib/administração & dosagem , Linfoma de Burkitt/tratamento farmacológico , MAP Quinase Quinase Quinases/metabolismo , Zearalenona/análogos & derivados , Transporte Ativo do Núcleo Celular , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Citoplasma/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Inibidores Enzimáticos/química , Humanos , NF-kappa B/metabolismo , Inibidores de Proteassoma/administração & dosagem , Ratos , Zearalenona/administração & dosagem
18.
Molecules ; 20(11): 20669-87, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26610443

RESUMO

The growing interest in toxic substances combined with advancements in biological sciences has shed a new light on the problem of mycotoxins contaminating feeds and foods. An interdisciplinary approach was developed by identifying dose-response relationships in key research concepts, including the low dose theory of estrogen-like compounds, hormesis, NOAEL dose, compensatory response and/or food tolerance, and effects of exposure to undesirable substances. The above considerations increased the researchers' interest in risk evaluation, namely: (i) clinical symptoms associated with long-term, daily exposure to low doses of a toxic compound; and (ii) dysfunctions at cellular or tissue level that do not produce clinical symptoms. Research advancements facilitate the extrapolation of results and promote the use of novel tools for evaluating the risk of exposure, for example exposure to zearalenone in pre-pubertal female dogs. The arguments presented in this paper suggest that low doses of zearalenone in commercial feeds stimulate metabolic processes and increase weight gains. Those processes are accompanied by lower proliferation rates in the ovaries, neoangiogenesis and vasodilation in the ovaries and the uterus, changes in the steroid hormone profile, and changes in the activity of hydroxysteroid dehydrogenases. All of the above changes result from exogenous hyperestrogenizm.


Assuntos
Estrogênios não Esteroides/administração & dosagem , Ovário/efeitos dos fármacos , Útero/efeitos dos fármacos , Zearalenona/administração & dosagem , Ração Animal , Animais , Cães , Feminino , Redes e Vias Metabólicas/efeitos dos fármacos , Ovário/citologia , Ovário/fisiologia , Receptores de Estrogênio/metabolismo , Maturidade Sexual , Útero/citologia , Útero/fisiologia
19.
Biosens Bioelectron ; 70: 447-54, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25863342

RESUMO

In this study, a novel and simple cell-based electrochemical biosensor was developed to assess the individual and combined toxicity of deoxynivalenol (DON) and zearalenone (ZEN) on BEL-7402 cells. The sensor was fabricated by modification with AuNPs, p-aminothiophenol, and folic acid in succession. The BEL-7402 cells which had a good activity were adhered on the electrode through the high affinity between the folate receptor and folic acid selectivity. We used the collagen to maintain the cell adhesion and viability. Electrochemical impedance spectroscopy (EIS) was developed to evaluate the individual and combined toxicity of DON and ZEN. Our results indicate that DON and ZEN caused a marked decrease in the cell viability in a dose-dependent manner. The value of electrochemical impedance spectroscopy decreased with the concentration of DON and ZEN in range of 0.1-20, 0.1-50 µg/ml with the detection limit as 0.03, 0.05 µg/ml, respectively, the IC50 for DON and ZEN as obtained by the proposed electrochemical method were 7.1 µg/ml and 24.6 µg/ml, respectively, and the combination of two mycotoxins appears to generate an additive response. The electrochemical cytotoxicity evaluation result was confirmed by biological assays. Compared to conventional methods, this electrochemical test is inexpensive, highly sensitive, and fast to respond, with long-term monitoring and real-time measurements. The proposed method provides a new avenue for evaluating the toxicity of mycotoxins.


Assuntos
Bioensaio/instrumentação , Sobrevivência Celular/efeitos dos fármacos , Espectroscopia Dielétrica/instrumentação , Testes de Toxicidade/instrumentação , Tricotecenos/toxicidade , Zearalenona/toxicidade , Linhagem Celular Tumoral , Combinação de Medicamentos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Dose Letal Mediana , Micotoxinas/administração & dosagem , Micotoxinas/uso terapêutico , Neoplasias Experimentais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tricotecenos/administração & dosagem , Zearalenona/administração & dosagem
20.
Chem Biol Interact ; 230: 50-7, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25682699

RESUMO

Male mice received lycopene for 10 days before a single oral administration of zearalenone (ZEA). After 48 h testes and blood were collected. Mice treated with lycopene/ZEA exhibited amelioration of the hematological changes. Lycopene prevented the reduction in the number and motility of spermatozoa and testosterone levels, indicating a protective effect in the testicular damage induced by ZEA. Lycopene was also effective in protecting against the decrease in glutathione-S-transferase, glutathione peroxidase, glutathione reductase and δ-aminolevulinic acid dehydratase activities caused by ZEA in the testes. Exposure of animals to ZEA induced modification of antioxidant and inflammatory status with increase of reduced glutathione (GSH) levels and increase of the oxidized glutathione, interleukins 1ß, 2, 6, 10, tumor necrosis factor-α and bilirubin levels. Lycopene prevented ZEA-induced changes in GSH levels and inhibited the processes of inflammation, reducing the damage induced by ZEA. Altogether, our results indicate that lycopene was able to prevent ZEA-induced damage in the mice.


Assuntos
Carotenoides/farmacologia , Inflamação/tratamento farmacológico , Substâncias Protetoras/farmacologia , Testículo/efeitos dos fármacos , Zearalenona/toxicidade , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/metabolismo , Bilirrubina/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Inflamação/metabolismo , Interleucinas/metabolismo , Licopeno , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Sintase do Porfobilinogênio/metabolismo , Testículo/patologia , Testosterona/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Zearalenona/administração & dosagem
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