RESUMO
Rabbit bucks (bodyweight 5 kg) underwent dietary intoxication with fumonisin B series mycotoxins (FB1 + FB2 + FB3, 15 mg/kg diet) for 14 days to test the applicability of positron emission tomography-magnetic resonance (PET MR) hybrid imaging in characterizing experimentally induced mild hepatotoxicosis. 18F-fluorodeoxyglucose (18F-FDG) radiotracer-aided imaging was performed before and after FBs administration on identical animals, and at both time points, blood was sampled for haematology and clinical chemistry. Kinetic PET image analysis revealed time-activity curves with uptake maxima below 1 min in the liver, renal cortex, portal vein, lung and coarctatio aortae. In the frame of static PET image analysis, based on the standardized uptake value (SUV), the so-called metabolic liver volume (MLV, liver volume defined by over 0.9 × average liver SUV) and the total liver glycolysis (TLG, MLV multiplied by the SUVmean) were calculated. Mycotoxicosis increased total liver glycolysis (p < 0.04) after 14 days and liver tissue TLG inhomogeneity was minimal. Pearson correlation between TLG and alkaline phosphatase (ALP) was positive (0.515), while negative with LDH and AST (- 0.721 and - 0.491, respectively). Results indicate a slight hepatic mycotoxin effect and significantly increased glucose uptake intensity, which has been sensitively detected with molecular imaging (18F-FDG PET MRI) in the rabbit model.
Assuntos
Fluordesoxiglucose F18 , Fumonisinas , Fígado , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Animais , Coelhos , Fumonisinas/toxicidade , Fígado/metabolismo , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Glucose/metabolismo , MasculinoRESUMO
Mycotoxins are secondary products produced primarily by fungi and are pathogens of animals and cereals, not only affecting agriculture and the food industry but also causing great economic losses. The development of rapid and sensitive methods for the detection of mycotoxins in food is of great significance for livelihood issues. This study employed an amino-functionalized zirconium luminescent metal-organic framework (LOF) (i.e., UiO-66-NH2). Click chemistry was utilized to assemble UiO-66-NH2 in a controlled manner, generating LOF assemblies to serve as probes for fluorescence-linked immunoassays. The proposed fluoroimmunoassay method for Zearalenone (ZEN) and Fumonisin B1 (FB1) detection based on the UiO-66-NH2 assembled probe (CLICK-FLISA) afforded a linear response range of 1-20 µmol/L for ZEN, 20 µmol/L for FB1, and a very low detection limit (0.048-0.065 µmol/L for ZEN; 0.048-0.065 µmol/L for FB1). These satisfying results demonstrate promising applications for on-site quick testing in practical sample analysis. Moreover, the amino functionalization may also serve as a modification strategy to design luminescent sensors for other food contaminants.
Assuntos
Fumonisinas , Estruturas Metalorgânicas , Zea mays , Zearalenona , Fumonisinas/análise , Zearalenona/análise , Estruturas Metalorgânicas/química , Zea mays/química , Química Click , Fluorimunoensaio/métodos , Técnicas Biossensoriais , Contaminação de Alimentos/análise , Limite de Detecção , Micotoxinas/análiseRESUMO
Mycotoxins, especially aflatoxin B1 (AFB1) and fumonisin B1 (FMB1), are common contaminants in cereal-based foods. Instances of contamination are predicted to increase due to the current challenges induced by climate change. Despite the health benefits of whole grains, the presence of mycotoxins in bran remains a concern. Nonetheless, previous research indicates that wheat bran can adsorb mutagens. Therefore, this study investigated the capacity of maize, wheat, and oat brans to adsorb AFB1 and FMB1 under varying in vitro conditions, including pH, binding time, temperature, particle size, and the amount of bran utilized. Maize bran demonstrated a high AFB1 adsorption capacity (>78%) compared to wheat and oat brans. However, FMB1 was not adsorbed by the brans, possibly due to its hydrophilic nature. Lower temperature (≤25 °C) enhanced AFB1 adsorption efficacy in wheat and oat bran, while for maize bran, the highest adsorption occurred at 37 °C. A linear model following Henry's law best explained AFB1 adsorption by the brans. Further studies identified the pericarp layer of bran as the primary site of AFB1 adsorption, with the initial liquid volume being a critical factor. The study concludes that bran could potentially act as an effective bioadsorbent. Further research is essential to confirm the adsorption efficacy and the bioavailability of AFB1 through in vivo experiments.
Assuntos
Aflatoxina B1 , Avena , Fibras na Dieta , Contaminação de Alimentos , Fumonisinas , Triticum , Zea mays , Zea mays/química , Fumonisinas/química , Triticum/química , Adsorção , Aflatoxina B1/química , Avena/química , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Temperatura , Concentração de Íons de HidrogênioRESUMO
This study aimed to determine whether oral fumonisin exposure contributes to the development of psoriasis. Oral administration of fumonisin B1 (FB1, 0.1 mg/kg) or fumonisin B2 (FB2, 0.1 mg/kg) was conducted for 10 days, in addition to the induction of psoriatic symptoms through topical application of 5% imiquimod cream from day 6 to day 10 (5 days) in female BALB/c mice. The results demonstrated that oral administration of FB2 significantly exacerbated psoriatic symptoms, including skin thickness, itching behavior, transepidermal water loss, immune cell infiltration in the dermis, and proinflammatory cytokine production. However, no changes were observed following exposure to FB1. Our results confirm that oral exposure to FB2 adversely affects the pathogenesis of psoriasis by increasing skin thickness and impairing barrier function.
Assuntos
Fumonisinas , Imiquimode , Camundongos Endogâmicos BALB C , Psoríase , Animais , Psoríase/induzido quimicamente , Psoríase/patologia , Psoríase/metabolismo , Imiquimode/efeitos adversos , Fumonisinas/toxicidade , Camundongos , Feminino , Administração Oral , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Citocinas/metabolismo , Modelos Animais de DoençasRESUMO
Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins widely found as cereal contaminants, and their co-consumption is associated with liver cancer. Both are immunotoxic, but their interactions have been little studied. This work was aimed to evaluate in mouse spleen mononuclear cells (SMC) the effects of the exposure to AFB1 (5-50 µM), FB1 (25-250 µM), and AFB1-FB1 mixtures (MIX) on the in vitro differentiation of regulatory T cells (Treg and Tr1-like) and Th17 cells, as well as elucidate the contribution of aryl hydrocarbon receptor (Ahr) in such effects. AFB1 and mainly MIX induced cytotoxicity in activated CD4 cells via Ahr signaling. AFB1 (5 µM) increased the Treg cell differentiation, but its combination with FB1 (25 µM) also reduced Th17 cell expansion by Ahr-dependent mechanisms. Therefore, this mixture could enhance the Treg/Th17 cell ratio and favor immunosuppression and escape from tumor immunosurveillance to a greater extent than individual mycotoxins. Whereas, AFB1-FB1 mixtures at medium-high doses inhibited the Tr1-like cell expansion induced by the individual mycotoxins and affected Treg and Th17 cell differentiation in Ahr-independent and dependent manners, respectively, which could alter anti-inflammatory and Th17 immune responses. Moreover, individual FB1 altered regulatory T and Th17 cell development independently of Ahr. In conclusion, AFB1 and FB1 interact by modifying Ahr signaling, which is involved in the immunotoxicity as well as in the alteration of the differentiation of Treg, Tr1-like, and Th17 cells induced by AFB1-FB1 mixtures. Therefore, Ahr is implicated in the regulation of the anti- and pro-inflammatory responses caused by the combination of AFB1 and FB1.
Assuntos
Aflatoxina B1 , Diferenciação Celular , Fumonisinas , Receptores de Hidrocarboneto Arílico , Linfócitos T Reguladores , Células Th17 , Receptores de Hidrocarboneto Arílico/metabolismo , Aflatoxina B1/toxicidade , Animais , Células Th17/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Fumonisinas/toxicidade , Camundongos , Diferenciação Celular/efeitos dos fármacosRESUMO
The electrochemical detection of biosensors is largely governed by the changes in physical properties of redox probes, which are susceptible to electrode substrate effects, inhibiting sensor sensitivity. In this work, a light-driven electrochemical biosensor based on a hybrid nanoantenna was developed for the sensitive detection of fumonisin B1 (FB1). The hybrid nanoantenna sensing interface was constructed by coupling CdSe quantum dots (QDs)-DNA nanowire and graphdiyne oxide composites loaded with methylene blue and gold nanorods (GDYO-MB-Au NRs) using a tetrahedral DNA nanostructure, which acted as a light-driven unit and an amplification unit, respectively. The hybrid nanoantenna with light-driven properties facilitated the alteration in the chemical properties of MB at the sensing interface; that is, MB was degraded under light illumination. The stripping of the CdSe QDs-DNA nanowire triggered by the binding of FB1 could degrade the light-driven capability, thereby improving the electrochemical signal through depressing MB degradation. Taking advantage of the photodegradation of MB by the hybrid nanoantenna, the developed biosensor reduced the background signal and increased the detection sensitivity. The developed biosensor exhibited a linear detection range from 0.5 fg mL-1 to 10 pg mL-1 and a detection limit down to 0.45 fg mL-1. This strategy shows great promise for the fabrication of highly sensitive electrochemical biosensors.
Assuntos
Técnicas Biossensoriais , DNA , Técnicas Eletroquímicas , Fumonisinas , Pontos Quânticos , Fumonisinas/análise , DNA/química , Pontos Quânticos/química , Luz , Compostos de Cádmio/química , Ouro/química , Compostos de Selênio/química , Nanotubos/química , Limite de Detecção , Nanofios/químicaRESUMO
Fusarium verticillioides produces fumonisins, which are mycotoxins inhibiting sphingolipid biosynthesis in humans, animals, and other eukaryotes. Fumonisins are presumed virulence factors of plant pathogens, but may also play a role in interactions between competing fungi. We observed higher resistance to added fumonisin B1 (FB1) in fumonisin-producing Fusarium verticillioides than in nonproducing F. graminearum, and likewise between isolates of Aspergillus and Alternaria differing in production of sphinganine-analog toxins. It has been reported that in F. verticillioides, ceramide synthase encoded in the fumonisin biosynthetic gene cluster is responsible for self-resistance. We reinvestigated the role of FUM17 and FUM18 by generating a double mutant strain in a fum1 background. Nearly unchanged resistance to added FB1 was observed compared to the parental fum1 strain. A recently developed fumonisin-sensitive baker's yeast strain allowed for the testing of candidate ceramide synthases by heterologous expression. The overexpression of the yeast LAC1 gene, but not LAG1, increased fumonisin resistance. High-level resistance was conferred by FUM18, but not by FUM17. Likewise, strong resistance to FB1 was caused by overexpression of the presumed F. verticillioides "housekeeping" ceramide synthases CER1, CER2, and CER3, located outside the fumonisin cluster, indicating that F. verticillioides possesses a redundant set of insensitive targets as a self-resistance mechanism.
Assuntos
Fumonisinas , Fusarium , Oxirredutases , Fumonisinas/metabolismo , Fusarium/genética , Fusarium/metabolismo , Fusarium/enzimologia , Oxirredutases/metabolismo , Oxirredutases/genética , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Aspergillus/genética , Aspergillus/metabolismo , Aspergillus/enzimologia , Alternaria/genética , Alternaria/enzimologiaRESUMO
Validamycin A (VMA) is an antifungal antibiotic derived from Streptomyces hygroscopicus commonly used in plant disease management. Surprisingly, VMA was discovered to impede the production of fumonisin B1 (FB1) in agricultural settings. However, the specific target of VMA in Fusarium verticillioides remained unclear. To unravel the molecular mechanism of VMA, ultrastructural observations unveiled damage to mitochondrial membranes. Trehalase (FvNth) was pinpointed as the target of VMA by utilizing a 3D-printed surface plasmon resonance sensor. Molecular docking identified Trp285, Arg447, Asp452, and Phe665 as the binding sites between VMA and FvNth. A ΔFvnth mutant lacking amino acids 250-670 was engineered through homologous recombination. Transcriptome analysis indicated that samples treated with VMA and ΔFvnth displayed similar expression patterns, particularly in the suppression of the FUM gene cluster. VMA treatment resulted in reduced trehalase and ATPase activity as well as diminished production of glucose, pyruvic acid, and acetyl-CoA. Conversely, these effects were absent in samples treated with ΔFvnth. This research proposes that VMA hinders acetyl-CoA synthesis by trehalase, thereby suppressing the FB1 biosynthesis. These findings present a novel target for the development of mycotoxin control agents.
Assuntos
Fumonisinas , Proteínas Fúngicas , Fusarium , Trealase , Fusarium/metabolismo , Fusarium/efeitos dos fármacos , Fusarium/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Fumonisinas/metabolismo , Trealase/genética , Trealase/metabolismo , Trealase/química , Trealase/antagonistas & inibidores , Simulação de Acoplamento Molecular , Inositol/análogos & derivados , Inositol/farmacologia , Inositol/química , Doenças das Plantas/microbiologia , Antifúngicos/farmacologia , Antifúngicos/química , Streptomyces/metabolismo , Streptomyces/genética , Streptomyces/químicaRESUMO
Fumonisin B1 (FB1) is a mycotoxin, a water-soluble metabolite produced by Fusarium cepacia, which mainly contaminates grain and its products and is acutely toxic and potentially carcinogenic to certain domestic animals. In this work, plasma nanocomposites of Fe3O4@Cu@Cu2O with magnetic and optoelectronic properties were synthesized as a sensing platform. On one hand, the surface plasmon resonance (SPR) of metallic Cu accelerates the electron transfer rate. On the other hand, plasma-induced resonance energy transfer of metals and semiconductors can improve the utilization efficiency of light energy. A split photoelectrochemical (PEC) sensor based on Fe3O4@Cu@Cu2O was proposed for the detection of FB1. The sensor has a wide linear range of 1.0-10 000 pg mL-1 and a low detection limit of 0.28 pg mL-1 (LOD, S/N = 3), which can realize the specific detection of FB1 in real samples.
Assuntos
Cobre , Técnicas Eletroquímicas , Fumonisinas , Limite de Detecção , Fumonisinas/química , Fumonisinas/análise , Cobre/química , Técnicas Eletroquímicas/métodos , Nanocompostos/química , Ressonância de Plasmônio de Superfície/métodos , Processos FotoquímicosRESUMO
Among cereal contaminants, mycotoxins are of concern due to their importance in terms of food and feed safety. The difficulty in establishing a diagnosis for mycotoxicosis relies on the fact that the effects are most often subclinical for chronic exposure and the most common scenario is multi-contamination by various toxins. Mycotoxin co-occurrence is a major food safety concern as additive or even synergic toxic impacts may occur, but also regarding current regulations as they mainly concern individual mycotoxin levels in specific foods and feed in the food chain. However, due to the large number of possible mycotoxin combinations, there is still limited knowledge on co-exposure toxicity data, which depends on several parameters. In this context, this systematic review aims to provide an overview of the toxic effects of two regulated mycotoxins, namely ochratoxin A and fumonisin B1. This review focused on the 2012-2022 period and analysed the occurrence in Europe of the selected mycotoxins in different food matrices (cereals and cereal-derived products), and their toxic impact, alone or in combination, on in vitro intestinal and hepatic human cells. To better understand and evaluate the associated risks, further research is needed using new approach methodologies (NAM), such as in vitro 3D models. KEY CONTRIBUTION: Cereals and their derived products are the most important food source for humans and feed for animals worldwide. This manuscript is a state of the art review of the literature over the last ten years on ochratoxin A and fumonisin B1 mycotoxins in these products in Europe as well as their toxicological effects, alone and in combination, on human cells. Future perspectives and some challenges regarding the assessment of toxicological effects of mycotoxins are also discussed.
Assuntos
Grão Comestível , Contaminação de Alimentos , Fumonisinas , Ocratoxinas , Ocratoxinas/toxicidade , Ocratoxinas/análise , Fumonisinas/toxicidade , Fumonisinas/análise , Grão Comestível/química , Humanos , Contaminação de Alimentos/análise , Europa (Continente) , AnimaisRESUMO
Monitoring modifications in membrane lipids in association with external stimuli/agents, including fumonisins (FUMs), is a widely employed approach to assess cellular metabolic response/status. FUMs are prevalent fusariotoxins worldwide that have diverse structures with varying toxicity across species; nevertheless, they can induce metabolic disturbances and disease, including cancer. The capacity of FUMs to disrupt membrane lipids, demonstrated across numerous species and organs/tissues, is ascribed to a multitude of factors/events, which range from direct to indirect effects. Certain events are well established, whereas the potential consequences of others remain speculative. The most notable effect is their resemblance to sphingoid bases, which impacts the synthesis of ceramides leading to numerous changes in lipids' composition that are not limited to sphingolipids' composition of the membranes. The next plausible scenario involves the induction of oxidative stress, which is considered an indirect/secondary effect of FUMs. Additional modes of action include modifications of enzyme activities and nuclear signals related to lipid metabolism, although these are likely not yet fully comprehended. This review provides in-depth insight into the current state of these events and their potential mechanistic actions in modifying membrane lipids, with a focus on long-chain fatty acids. This paper also presents a detailed description of the reported modifications to membrane lipids by FUMs.
Assuntos
Fumonisinas , Lipídeos de Membrana , Fumonisinas/toxicidade , Lipídeos de Membrana/metabolismo , Animais , Humanos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Esfingolipídeos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacosRESUMO
Fusarium verticillioides has a substantial impact on maize production, commonly leading to maize ear rot and the production of fumonisin, a mycotoxin that poses health risks to both humans and animals. Currently, there is a lack of molecular targets for preventing the disease and controlling the toxin. The biological functions of oxysterol-binding proteins (OSBP) in filamentous fungi remain unclear. In this research, 7 oxysterol-binding protein-related proteins were identified in F. verticillioides, and these proteins were obtained through prokaryotic expression and purification. FvOshC was identified as the specific protein that binds to ergosterol through fluorescence titration. Gene knockout complementation techniques confirmed that FvOSHC plays a positive role, establishing it as a novel global regulatory protein involved in the pathogenicity and FB1 biosynthesis in F. verticillioides. Additionally, the interaction between FvOshC and FvSec14 was identified using yeast two-hybrid techniques. Moreover, computer-aided drug design technology was utilized to identify the receptor molecule Xanthatin based on FvOshC. The inhibitory effect of Xanthatin on the growth of F. verticillioides and the synthesis of FB1 was significantly demonstrated. These findings provide valuable insights that can aid in the management of mycotoxin pollution.
Assuntos
Fumonisinas , Proteínas Fúngicas , Fusarium , Doenças das Plantas , Zea mays , Fumonisinas/metabolismo , Fusarium/metabolismo , Fusarium/genética , Zea mays/microbiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Doenças das Plantas/microbiologia , Regulação Fúngica da Expressão GênicaRESUMO
The high osmolarity glycerol 1 mitogen-activated protein kinase (Hog1-MAPK) cascade genes are important for diverse biological processes. The activated Hog1 upon multiple environmental stress stimuli enters into the nucleus where it directly phosphorylates transcription factors to regulate various physiological processes in phytopathogenic fungi. However, their roles have not been well-characterized in Fusarium verticillioides. In this study, FvHog1 is identified and functionally analyzed. The findings reveal that the phosphorylation level and nuclear localization of FvHog1 are increased in Fumonisin B1 (FB1)-inducing condition to regulate the expression of FB1 biosynthesis FUM genes. More importantly, the deletion mutants of Hog1-MAPK pathway show increased sensitivity to Ca2+ stress and elevated intracellular Ca2+ content. The phosphorylation level and nuclear localization of FvHog1 are increased with Ca2+ treatment. Furthermore, our results show that FvHog1 can directly phosphorylate Ca2+-responsive zinc finger transcription factor 1 (FvCrz1) to regulate Ca2+ homeostasis. In conclusion, our findings indicate that FvHog1 is required for FB1 biosynthesis, pathogenicity and Ca2+ homeostasis in F. verticillioides. It provides a theoretical basis for effective prevention and control maize ear and stalk rot disease.
Assuntos
Cálcio , Fumonisinas , Proteínas Fúngicas , Fusarium , Homeostase , Proteínas Quinases Ativadas por Mitógeno , Fusarium/metabolismo , Fusarium/genética , Cálcio/metabolismo , Fumonisinas/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Fosforilação , Regulação Fúngica da Expressão GênicaRESUMO
Early transition metal carbides (MXene) hybridized by precious metals open a door for innovative electrochemical biosensing device design. Herein, we present a facile one-pot synthesis of gold nanoparticles (AuNPs)-doped two-dimensional (2D) titanium carbide MXene nanoflakes (Ti3C2Tx/Au). Ti3C2Tx MXene exhibits high electrical conductivity and yields synergistic signal amplification in conjunction with AuNPs leading to excellent electrochemical performance. Thus Ti3C2Tx/Au hybrid nanostructure can be used as an electrode platform for the electrochemical analysis of various targets. We used screen-printed electrodes modified with the Ti3C2Tx/Au electrode and functionalized with different biorecognition elements to detect and quantify an antibiotic, ampicillin (AMP), and a mycotoxin, fumonisin B1 (FB1). The ultralow limits of detection of 2.284 pM and 1.617 pg.mL-1, which we achieved respectively for AMP and FB1 are far lower than their corresponding maximum residue limits of 2.8 nM in milk and 2 to 4 mg kg-1 in corn products for human consumption set by the United States Food and Drug Administration. Additionally, the linear range of detection and quantification of AMP and FB1 were, respectively, 10 pM to 500 nM and 10 pg mL-1 to 1 µg mL-1. The unique structure and excellent electrochemical performance of Ti3C2Tx/Au nanocomposite suggest that it is highly suitable for anchoring biorecognition entities such as antibodies and oligonucleotides for monitoring various deleterious contaminants in agri-food products.
Assuntos
Ampicilina , Técnicas Eletroquímicas , Fumonisinas , Ouro , Limite de Detecção , Nanopartículas Metálicas , Titânio , Fumonisinas/análise , Ouro/química , Ampicilina/análise , Ampicilina/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Titânio/química , Técnicas Biossensoriais/métodos , Leite/química , Antibacterianos/análise , Eletrodos , Contaminação de Alimentos/análise , AnimaisRESUMO
Maize (Zea mays L.) is of socioeconomic importance as an essential food for human and animal nutrition. However, cereals are susceptible to attack by mycotoxin-producing fungi, which can damage health. The methods most commonly used to detect and quantify mycotoxins are expensive and time-consuming. Therefore, alternative non-destructive methods are required urgently. The present study aimed to use near-infrared spectroscopy with hyperspectral imaging (NIR-HSI) and multivariate image analysis to develop a rapid and accurate method for quantifying fumonisins in whole grains of six naturally contaminated maize cultivars. Fifty-eight samples, each containing 40 grains, were subjected to NIR-HSI. These were subsequently divided into calibration (38 samples) and prediction sets (20 samples) based on the multispectral data obtained. The averaged spectra were subjected to various pre-processing techniques (standard normal variate (SNV), first derivative, or second derivative). The most effective pre-treatment performed on the spectra was SNV. Partial least squares (PLS) models were developed to quantify the fumonisin content. The final model presented a correlation coefficient (R2) of 0.98 and root mean square error of calibration (RMSEC) of 508 µg.kg-1 for the calibration set, an R2 of 0.95 and root mean square error of prediction (RMSEP) of 508 µg.kg-1 for the test validation set and a ratio of performance to deviation of 4.7. It was concluded that NIR-HSI with partial least square regression is a rapid, effective, and non-destructive method to determine the fumonisin content in whole maize grains.
Assuntos
Fumonisinas , Imageamento Hiperespectral , Espectroscopia de Luz Próxima ao Infravermelho , Zea mays , Zea mays/química , Fumonisinas/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Imageamento Hiperespectral/métodos , Reprodutibilidade dos Testes , Quimiometria/métodosRESUMO
Fumonisin B1 (FB1), a water-soluble mycotoxin released by Fusarium moniliforme Sheld, is widely present in corn and its derivative products, and seriously endangers human life and health. Recent studies have reported that FB1 can lead to pyroptosis, however, the mechanisms by which FB1-induced pyroptosis remain indistinct. In the present study, we aim to investigate the mechanisms of pyroptosis in intestinal porcine epithelial cells (IPEC-J2) and the relationship between FB1-induced endoplasmic reticulum stress (ERS) and pyroptosis. Our experimental results showed that the pyroptosis protein indicators in IPEC-J2 were significantly increased after exposure to FB1. The ERS markers, including glucose-regulated Protein 78 (GRP78), PKR-like ER kinase protein (PERK), and preprotein translocation factor (Sec62) were also significantly increased. Using small interfering RNA silencing of PERK or Sec62, the results demonstrated that upregulation of Sec62 activates the PERK pathway, and activation of the PERK signaling pathway is upstream of FB1-induced pyroptosis. After using the ERS inhibitor 4-PBA reduced the FB1-triggered intestinal injury by the Sec62-PERK pathway. In conclusion, we found that FB1 induced pyroptosis by upregulating Sec62 to activate the PERK pathway, and mild ERS alleviates FB1-triggered damage. It all boils down to one fact, the study provides a new perspective for further, and improving the toxicological mechanism of FB1.
Assuntos
Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Piroptose , Transdução de Sinais , eIF-2 Quinase , Piroptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Animais , eIF-2 Quinase/metabolismo , eIF-2 Quinase/genética , Suínos , Transdução de Sinais/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático/metabolismo , Linhagem Celular , Intestinos/efeitos dos fármacos , Intestinos/patologia , Células Epiteliais/metabolismo , Células Epiteliais/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , FumonisinasRESUMO
Mycotoxin contamination of agricultural commodities is a global public health problem that has remained elusive to various mitigation approaches, particularly in developing countries. Climate change and its impact exacerbates South Africa's vulnerability to mycotoxin contamination, and significantly threatens its's food systems, public health, and agro-economic development. Herein we analyse sixteen years (2005/2006-2020/2021) of annual national meteorological data on South Africa which reveals both systematic and erratic variability in critical climatic factors known to influence mycotoxin contamination in crops. Within the same study period, data on fumonisin (FB) monitoring show clear climate-dependent trends. The strongest positive warming trend is observed between 2018/2019 and 2019/2020 (0.51 °C/year), and a strong positive correlation is likewise established between FB contamination and temperature (r ranging from 0.6 to 0.9). Four machine learning models, viz support vector machines, eXtreme gradient boosting, random forest, and orthogonal partial least squares, are generalized on the historical data with suitable performance (RMSE as low as 0.00). All the adopted models are able to predict future FB contamination patterns with reasonable precision (R2 ranging from 0.34 to 1.00). The most important model feature for predicting average FB contamination (YA) is the historical pattern of average FB contamination in maize within the region (ΣFBs_avg). The two most significant features in modelling maximum FB contamination (YM) are minimum temperature from the CMIP6 data (Pro_tempMIN) and observed precipitation from the CRU data (O_prep). Our study provides strong evidence of the impact of climate change on FB in South Africa and reiterates the significance of machine learning modelling in predicting mycotoxin contamination in light of changing climatic conditions, which could facilitate early warnings and the adoption of relevant mitigation measures that could help in mycotoxin risk management and control.
Assuntos
Mudança Climática , Fumonisinas , Zea mays , África do Sul , Fumonisinas/análise , Zea mays/microbiologia , Clima , Contaminação de Alimentos/análise , Aprendizado de Máquina , Produtos AgrícolasRESUMO
The neurotoxicity of fumonisin B1 (FB1), a commonly detected mycotoxin in crops and the environment, has attracted considerable attention in recent years. However, no effective method for eliminating FB1 completely exists due to the thermal stability and water solubility of this mycotoxin. Magnolol (MAG) is a neolignane with antioxidative and neuroprotective effects. It has been applied in neurotoxicity treatment. However, the application of MAG to attenuate FB1-induced toxicity has not been reported. This study explored the protective mechanism of MAG against FB1-induced damage in C6 cells through antioxidant and lipid metabolism modulation. Results showed that exposure to 15 µM FB1 caused oxidative stress by changing the levels of malondialdehyde, reactive oxygen species, total superoxide dismutase, catalase, and total glutathione. These changes were reversed by MAG addition, especially at the concentration of 80 µM. The protective effects of MAG were further confirmed by the reduction in the phosphorylation levels of proteins in the MAPK signaling pathway. Lipidomics analysis identified 263 lipids, which belong to 24 lipid classes. Among all of the identified lipids, triglycerides (TGs), diglycerides (DGs), phosphatidylcholines (PCs), wax monoesters (WEs), Cers, and phosphatidylethanolamines (PEs) were major categories. Moreover, nine categories of lipids showed the opposite change trend in the FB1 exposure and MAG 80 groups. A further investigation of the 34 co-occurring differential lipids with remarkable changes (P value < 0.05 and VIP value > 1) in the control, FB1 exposure, and MAG 80 groups was performed. Therein, nine lipids (PCs, LPCs, and SM) were screened out as potential biomarkers to reveal the cytoprotective effects of MAG. This work is the first to investigate the rescue mechanism of MAG in FB1-induced cytotoxicity. The obtained results may expand the application of MAG to alleviate the toxicity of mycotoxins.
Assuntos
Compostos de Bifenilo , Fumonisinas , Lignanas , Metabolismo dos Lipídeos , Estresse Oxidativo , Fumonisinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lignanas/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular , Ratos , Fármacos Neuroprotetores/farmacologia , Malondialdeído/metabolismo , Superóxido Dismutase/metabolismo , Lipidômica , Glutationa/metabolismoRESUMO
Fumonisin B1 (FB1), one of the most widely distributed mycotoxins found in grains and feeds as contaminants, affects many organs including the kidney once ingested. However, the nephrotoxicity of FB1 remains to be further uncovered. The connection between necroptosis and nephrotoxicity of FB1 has been investigated in this study. The results showed that mice exposed to high doses of FB1 (2.25 mg/kg b.w.) developed kidney damage, with significant increases in proinflammatory cytokines (Il-6, Il-1ß), kidney injury-related markers (Ngal, Ntn-1), and gene expressions linked to necroptosis (Ripk1, Ripk3, Mlkl). The concentration-dependent damage effects of FB1 on PK-15 cells contain cytotoxicity, cellular inflammatory response, and necroptosis. These FB1-induced effects can be neutralized by pretreatment with the necroptosis inhibitor Nec-1. Additionally, FB1 caused mitochondrial damage and mitophagy in vivo and in vitro, whereas Mdivi-1, a mitophagy inhibitor, prevented these effects on PK-15 cells as well as, more crucially, necroptosis. In conclusion, the RIPK1/RIPK3/MLKL signal route of necroptosis, which may be controlled by mitophagy, mediated nephrotoxicity of FB1. Our findings clarify the underlying molecular pathways of FB1-induced nephrotoxicity.