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1.
Proc Natl Acad Sci U S A ; 121(16): e2314426121, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38574017

ABSTRACT

Epstein-Barr Virus (EBV) infects more than 90% of the adult population worldwide. EBV infection is associated with Burkitt lymphoma (BL) though alone is not sufficient to induce carcinogenesis implying the involvement of co-factors. BL is endemic in African regions faced with mycotoxins exposure. Exposure to mycotoxins and oncogenic viruses has been shown to increase cancer risks partly through the deregulation of the immune response. A recent transcriptome profiling of B cells exposed to aflatoxin B1 (AFB1) revealed an upregulation of the Chemokine ligand 22 (CCL22) expression although the underlying mechanisms were not investigated. Here, we tested whether mycotoxins and EBV exposure may together contribute to endemic BL (eBL) carcinogenesis via immunomodulatory mechanisms involving CCL22. Our results revealed that B cells exposure to AFB1 and EBV synergistically stimulated CCL22 secretion via the activation of Nuclear Factor-kappa B pathway. By expressing EBV latent genes in B cells, we revealed that elevated levels of CCL22 result not only from the expression of the latent membrane protein LMP1 as previously reported but also from the expression of other viral latent genes. Importantly, CCL22 overexpression resulting from AFB1-exposure in vitro increased EBV infection through the activation of phosphoinositide-3-kinase pathway. Moreover, inhibiting CCL22 in vitro and in humanized mice in vivo limited EBV infection and decreased viral genes expression, supporting the notion that CCL22 overexpression plays an important role in B cell infection. These findings unravel new mechanisms that may underpin eBL development and identify novel pathways that can be targeted in drug development.


Subject(s)
Burkitt Lymphoma , Epstein-Barr Virus Infections , Animals , Mice , Herpesvirus 4, Human/genetics , Epstein-Barr Virus Infections/complications , Aflatoxin B1/toxicity , Ligands , Burkitt Lymphoma/metabolism , Chemokines , Carcinogenesis
2.
Toxins (Basel) ; 16(3)2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38535826

ABSTRACT

Poultry may face simultaneous exposure to aflatoxin B1 (AFB1) and tiamulin (TIA), given mycotoxin contamination and antibiotic use. As both mycotoxins and antibiotics can affect cytochrome P450 enzymes (CYP450), our study aimed to explore their interaction. We developed UHPLC-MS/MS methods for the first-time determination of the interaction between TIA and AFB1 in vitro and in vivo in broiler chickens. The inhibition assay showed the half maximal inhibitory concentration (IC50) values of AFB1 and TIA in chicken liver microsomes are more than 7.6 µM, indicating an extremely weak inhibitory effect on hepatic enzymes. Nevertheless, the oral TIA pharmacokinetic results indicated that AFB1 significantly increased the area under the plasma concentration-time curve (AUClast) of TIA by 167% (p < 0.01). Additionally, the oral AFB1 pharmacokinetics revealed that TIA increased the AUClast and mean residence time (MRT) of AFB1 by 194% (p < 0.01) and 136%, respectively. These results suggested that the observed inhibition may be influenced by other factors, such as transport. Therefore, it is meaningful to further explore transport and other enzymes, involved in the interaction between AFB1 and TIA. Furthermore, additional clinical studies are necessary to thoroughly assess the safety of co-exposure with mycotoxins and antibiotics.


Subject(s)
Aflatoxin B1 , Chickens , Animals , Tandem Mass Spectrometry , Cytochrome P-450 Enzyme System , Anti-Bacterial Agents , Diterpenes
3.
Heliyon ; 10(1): e23025, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38205294

ABSTRACT

Contamination with mycotoxins has been a worldwide food safety concern for several decades, and food processing has been suggested as a potential method to mitigate their presence. In this study, the influence of traditional dehulling (TD) on the mycotoxin reduction and metabolites profile of fermented white maize products obtained via natural and three controlled fermentation methods (involving Lactobacillus fermentum, Lactobacillus plantarum, and their mixed cultures) was examined. Gas chromatography coupled with high resolution time-of-flight mass spectrometry (GC-HRTOF-MS) and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) were employed. TD brought the levels of fumonisin B1 (FB1) and B2 (FB2) in the white maize below the regulatory limit set by the European Union (EU) for maize consumed by humans. While TD increased the concentration of several mycotoxins in the fermented maize products obtained from other studied fermentation methods, it primarily reduced aflatoxin B1 (AFB1), FB1, deoxynivalenol, and 15-acetyldeoxynivalenol in the L. plantarum-fermented products. By tempering the dehulled maize, a solid-state fermentation process began. This was used in TD to make it easier to remove the pericarp. GC-HR-TOF-MS metabolomics revealed that TD brought about the generation of 12 additional compounds in the dehulled maize though some metabolites in the whole maize were lost/biotransformed. The fermented dehulled maize products obtained from the four studied fermentation procedures contained fewer compounds than the fermented whole maize products. Overall, the analysis showed that all fermented maize (whole and dehulled) produced had varied nutritional metabolites and mycotoxin concentrations below the EU maximum level, except for fermented maize obtained from mixed strains (AFB1 + AFB2 > 4.0 g/kg).

4.
Food Chem Toxicol ; 182: 114183, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37951345

ABSTRACT

Mycotoxins are secondary metabolites produced by fungi such as Aspergillus, Alternaria, and Penicillium, affecting nearly 80% of global food crops. Tenuazonic acid (TeA) is the major mycotoxin produced by Alternaria alternata, a prevalent pathogen affecting plants, fruits, and vegetables. TeA is notably prevalent in European diets, however, TeA biomarkers of exposure and metabolites remain unknown. This research aims to bridge this knowledge-gap by gaining insights about human TeA exposure and metabolization. Nine subjects were divided into two groups. The first group received a single bolus of TeA at the Threshold of Toxicological Concern (TTC) to investigate the presence of TeA urinary biomarkers, while the second group served as a control. Sixty-nine urinary samples were prepared and analyzed using UPLC-Xevo TQ-XS for TeA quantification and UPLC-Orbitrap Exploris for polar metabolome acquisition. TeA was rapidly excreted during the first 13 h and the fraction extracted was 0.39 ± 0.22. The polar metabolome compounds effectively discriminating the two groups were filtered using Orthogonal Partial Least Squares-Discriminant Analysis and subsequently annotated (n = 122) at confidence level 4. Finally, the urinary metabolome was compared to in silico predicted TeA metabolites. Nine metabolites, including oxidized, N-alkylated, desaturated, glucuronidated, and sulfonated forms of TeA were detected.


Subject(s)
Mycotoxins , Tenuazonic Acid , Humans , Tenuazonic Acid/analysis , Tenuazonic Acid/metabolism , Mycotoxins/analysis , Fruit/chemistry , Metabolomics , Crops, Agricultural/metabolism , Alternaria/metabolism
5.
Environ Int ; 182: 108326, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38000237

ABSTRACT

Deoxynivalenol (DON) is a mycotoxin frequently observed in cereals and cereal-based foods, with reported toxicological effects including reduced body weight, immunotoxicity and reproductive defects. The European Food Safety Authority used traditional risk assessment approaches to derive a deterministic Tolerable Daily Intake (TDI) of 1 µg/kg-day, however data from human biomarkers studies indicate widespread and variable exposure worldwide, necessitating more sophisticated and advanced methods to quantify population risk. The World Health Organization/International Programme on Chemical Safety (WHO/IPCS) has previously used DON as a case example in replacing the TDI with a probabilistic toxicity value, using default uncertainty and variability distributions to derive the Human Dose corresponding to an effect size M in the Ith percentile of the population (HDMI) for M = 5 % decrease in body weight and I = 1 %. In this study, we extend this case study by incorporating (1) Bayesian modeling approaches, (2) using both in vivo data and in vitro population new approach methods to replace default distributions for interspecies toxicokinetic (TK) differences and intraspecies TK and toxicodynamic (TD) variability, and (3) integrating biomonitoring data and probabilistic dose-response functions to characterize population risk distributions. We first derive an HDMI of 5.5 [1.4-24] µg/kg-day, also using TK modeling to converted the HDMI to Biomonitoring Equivalents, BEMI for comparison with biomonitoring data, with a blood BEMI of 0.53 [0.17-1.6] µg/L and a urinary excretion BEMI of 3.9 [1.0-16] µg/kg-day. We then illustrate how this integrative approach can advance quantitative risk characterization using two human biomonitoring datasets, estimating both the fraction of population with an effect size M ≥ 5 % as well as the distribution of effect sizes. Overall, we demonstrate that integration of Bayesian modeling, human biomonitoring data, and in vitro population-based TD data within the WHO/IPCS probabilistic framework yields more accurate, precise, and comprehensive risk characterization.


Subject(s)
Mycotoxins , Humans , Mycotoxins/toxicity , Biological Monitoring , Bayes Theorem , Risk Assessment/methods , Edible Grain , Body Weight
6.
Toxins (Basel) ; 15(9)2023 09 20.
Article in English | MEDLINE | ID: mdl-37756008

ABSTRACT

The aim of this systematic review is to provide an update on the occurrence and co-occurrence of selected non-regulated mycotoxins and provide an overview of current regulations. Fifteen non-regulated mycotoxins were found in 19 food categories worldwide. On top of that, 38 different combinations of non-regulated mycotoxins were found, with mixtures varying from binary combinations up to 12 mycotoxins. Taking into consideration the amount of evidence regarding the prevalence and co-occurrence of non-regulated mycotoxins, future steps should be taken considering continuous monitoring, scientific exchange, and generation of high-quality data. To enhance data quality, guidelines outlining the minimum quality criteria for both occurrence data and metadata are needed. By doing so, we can effectively address concerns related to the toxicity of non-regulated mycotoxins. Furthermore, obtaining more data concerning the co-occurrence of both regulated and non-regulated mycotoxins could aid in supporting multiple chemical risk assessment methodologies. Implementing these steps could bolster food safety measures, promote evidence-based regulations, and ultimately safeguard public health from the potential adverse effects of non-regulated mycotoxins.


Subject(s)
Data Accuracy , Mycotoxins , Fenbendazole , Food , Food Safety
7.
Nutrients ; 15(18)2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37764838

ABSTRACT

Fortified balanced energy-protein (BEP) supplementation is a promising intervention for improving maternal health, birth outcomes and infant growth in low- and middle-income countries. This nested biospecimen sub-study aimed to evaluate the physiological effect of multi-micronutrient-fortified BEP supplementation on pregnant and lactating women and their infants. Pregnant women (15-40 years) received either fortified BEP and iron-folic acid (IFA) (intervention) or IFA only (control) throughout pregnancy. The same women were concurrently randomized to receive either a fortified BEP supplement during the first 6 months postpartum in combination with IFA for the first 6 weeks (i.e., intervention) or the postnatal standard of care, which comprised IFA alone for 6 weeks postpartum (i.e., control). Biological specimens were collected at different timepoints. Multi-omics profiles will be characterized to assess the mediating effect of BEP supplementation on the different trial arms and its effect on maternal health, as well as birth and infant growth outcomes. The mediating effect of the exposome in the relationship between BEP supplementation and maternal health, birth outcomes and infant growth were characterized via biomonitoring markers of air pollution, mycotoxins and environmental contaminants. The results will provide holistic insight into the granular physiological effects of prenatal and postnatal BEP supplementation.


Subject(s)
Biological Monitoring , Infant Health , Pregnancy , Infant , Infant, Newborn , Humans , Female , Burkina Faso , Lactation , Multiomics , Folic Acid , Iron , Dietary Supplements , Randomized Controlled Trials as Topic
8.
Toxins (Basel) ; 15(4)2023 04 16.
Article in English | MEDLINE | ID: mdl-37104223

ABSTRACT

Mycotoxins can be transferred to breast milk during lactation. Hence, the presence of multiple mycotoxins (aflatoxins B1, B2, G1, G2, and M1, alpha and beta zearalanol, deoxynivalenol, fumonisins B1, B2, B3, and hydrolyzed B1, nivalenol, ochratoxin A, ochratoxin alpha, and zearalenone) in breast milk samples was assessed in our study. Furthermore, the relationship between total fumonisins and pre/post-harvest and the women's dietary practices was examined. Liquid chromatography coupled with tandem mass spectrometry was used to analyze the 16 mycotoxins. An adjusted censored regression model was fitted to identify predictors of mycotoxins, i.e., total fumonisins. We detected only fumonisin B2 (15% of the samples) and fumonisin B3 (9% of the samples) while fumonisin B1 and nivalenol were detected only in a single breast milk sample. No association between total fumonisins and pre/post-harvest and dietary practices was found (p < 0.05). The overall exposure to mycotoxins was low in the studied women, although fumonisins contamination was not negligible. Moreover, the recorded total fumonisins was not associated with any of the pre/post-harvest and dietary practices. Therefore, to better identify predictors of fumonisin contamination in breast milk, longitudinal studies with food samples in addition to breast milk samples and with larger sample sizes are needed for the future.


Subject(s)
Mycotoxins , Female , Humans , Mycotoxins/analysis , Lactation , Ethiopia , Milk, Human/chemistry , Food Contamination/analysis
9.
Pharmaceutics ; 15(3)2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36986755

ABSTRACT

Mycotoxins such as aflatoxin B1 (AFB1) are secondary fungal metabolites present in food commodities and part of one's daily exposure, especially in certain regions, e.g., sub-Saharan Africa. AFB1 is mostly metabolised by cytochrome P450 (CYP) enzymes, namely, CYP1A2 and CYP3A4. As a consequence of chronic exposure, it is interesting to check for interactions with drugs taken concomitantly. A physiologically based pharmacokinetic (PBPK) model was developed based on the literature and in-house-generated in vitro data to characterise the pharmacokinetics (PK) of AFB1. The substrate file was used in different populations (Chinese, North European Caucasian and Black South African), provided by SimCYP® software (v21), to evaluate the impact of populations on AFB1 PK. The model's performance was verified against published human in vivo PK parameters, with AUC ratios and Cmax ratios being within the 0.5-2.0-fold range. Effects on AFB1 PK were observed with commonly prescribed drugs in South Africa, leading to clearance ratios of 0.54 to 4.13. The simulations revealed that CYP3A4/CYP1A2 inducer/inhibitor drugs might have an impact on AFB1 metabolism, altering exposure to carcinogenic metabolites. AFB1 did not have effects on the PK of drugs at representative exposure concentrations. Therefore, chronic AFB1 exposure is unlikely to impact the PK of drugs taken concomitantly.

10.
Food Chem ; 404(Pt B): 134694, 2023 Mar 15.
Article in English | MEDLINE | ID: mdl-36323034

ABSTRACT

Microbial confrontation is ubiquitously present in nature, such as mycoparasitism, competition and antibiosis between biocontrol agents and microbial pathogens. However, the internal metabolic responses of fungal pathogens under microbial interaction scenario have been scarcely investigated. In this study, we set up an integrated mycotoxin analysis and non-targeted metabolomics workflow to decipher metabolic changes of Alternaria pathogens when confronted with selected Trichoderma strains, as well as mycotoxin metabolization in the Trichoderma spp. Results demonstrated that Trichoderma spp. significantly influenced mycotoxin production and whole metabolome of Alternaria pathogens when in cocultivation, and one Trichoderma strain could metabolize alternariol into its hydroxylated form. These differential metabolites revealed fungal physiological alternations in various confrontation conditions. In all, a MS-based strategy was proposed to investigate microbial metabolic profiles under fungal/fungal and fungal/mycotoxin cocultivation, and this generic methodology would be significant for understanding the occurrence and change of food contaminants in microbial interactions.


Subject(s)
Mycotoxins , Trichoderma , Alternaria/metabolism , Plant Diseases/microbiology , Trichoderma/genetics , Trichoderma/metabolism , Antibiosis , Mycotoxins/metabolism
11.
Int J Mol Sci ; 23(24)2022 Dec 08.
Article in English | MEDLINE | ID: mdl-36555197

ABSTRACT

Volatile organic compounds (VOCs) are secondary metabolites of varied chemical nature that are emitted by living beings and participate in their interactions. In addition, some VOCs called bioactive VOCs cause changes in the metabolism of other living species that share the same environment. In recent years, knowledge on VOCs emitted by Aspergillus flavus, the main species producing aflatoxin B1 (AFB1), a highly harmful mycotoxin, has increased. This review presents an overview of all VOCs identified as a result of A. flavus toxigenic (AFB1-producing) and non-toxigenic (non AFB1-producing) strains growth on different substrates, and the factors influencing their emissions. We also included all bioactive VOCs, mixes of VOCs or volatolomes of microbial species that impact A. flavus growth and/or related AFB1 production. The modes of action of VOCs impacting the fungus development are presented. Finally, the potential applications of VOCs as biocontrol agents in the context of mycotoxin control are discussed.


Subject(s)
Aspergillus flavus , Volatile Organic Compounds , Aspergillus flavus/metabolism , Aflatoxin B1 , Volatile Organic Compounds/pharmacology , Volatile Organic Compounds/metabolism
12.
Toxins (Basel) ; 14(12)2022 12 14.
Article in English | MEDLINE | ID: mdl-36548770

ABSTRACT

Mycotoxin contamination is a global food safety issue leading to major public health concerns. Repeated exposure to multiple mycotoxins not only has repercussions on human health but could theoretically also lead to interactions with other xenobiotic substances-such as drugs-in the body by altering their pharmacokinetics and/or pharmacodynamics. The combined effects of chronic drug use and mycotoxin exposure need to be well understood in order to draw valid conclusions and, in due course, to develop guidelines. The aim of this review is to focus on food contaminants, more precisely on mycotoxins, and drugs. First, a description of relevant mycotoxins and their effects on human health and metabolism is presented. The potential for interactions of mycotoxins with drugs using in vitro and in vivo animal experiments is summarized. Predictive software tools for unraveling mycotoxin-drug interactions are proposed and future perspectives on this emerging topic are highlighted with a view to evaluate associated risks and to focus on precision medicine. In vitro and in vivo animal studies have shown that mycotoxins affect CYP450 enzyme activity. An impact from drugs on mycotoxins mediated via CYP450-enzymes is plausible; however, an impact of mycotoxins on drugs is less likely considering the much smaller dose exposure to mycotoxins. Drugs that are CYP450 perpetrators and/or substrates potentially influence the metabolism of mycotoxins, metabolized via these CYP450 enzymes. To date, very little research has been conducted on this matter. The only statistically sound reports describe mycotoxins as victims and drugs as perpetrators in interactions; however, more analysis on mycotoxin-drug interactions needs to be performed.


Subject(s)
Mycotoxins , Animals , Humans , Mycotoxins/toxicity , Mycotoxins/analysis , Food Contamination/analysis , Food Safety , Public Health , Drug Contamination
13.
Cell Rep ; 41(2): 111454, 2022 10 11.
Article in English | MEDLINE | ID: mdl-36223738

ABSTRACT

Estrogen receptor ß (ERß) and NOD-like receptor family pyrin domain containing 6 (NLRP6) are highly expressed in intestinal tissues. Loss of ERß and NLRP6 exacerbate colitis in mouse models; however, the underlying mechanisms are incompletely understood. Here, we report that ERß directly activates the NLRP6 gene expression via binding to estrogen responsive element of Nlrp6 gene promoter. ERß also physically interacts with the NLRP6 nucleotide-binding domain and promotes NLRP6 inflammasome assembly. The ERß-NLRP6 axis then interacts with multiple autophagy-related proteins, including ULK1, BECN1, ATG16L1, LC3B, and p62, and affects the autophagosome biogenesis and autophagic flux. Finally, NLRP6-mediated autophagy suppresses the inflammatory response by promoting the K48-linked polyubiquitination of ASC, Casp-1 p20, IL-1ß, TNF-α, and prohibitin-2. Thus, ERß-NLRP6 direct an anti-inflammatory response by promoting autophagy. Our work uncovers an ERß-NLRP6-autophagy pathway as a regulatory mechanism that maintains intestinal epithelial cell homeostasis and facilitates tissue repair in colitis.


Subject(s)
Colitis , Estrogen Receptor beta , Receptors, Cell Surface , Animals , Anti-Inflammatory Agents , Autophagy/genetics , Colitis/genetics , Estrogen Receptor beta/genetics , Estrogens , Inflammasomes/metabolism , Mice , NLR Proteins , Nucleotides , Receptors, Cell Surface/genetics , Tumor Necrosis Factor-alpha
14.
Nutrients ; 14(17)2022 Aug 30.
Article in English | MEDLINE | ID: mdl-36079840

ABSTRACT

BACKGROUND: Mycotoxins have been suggested to contribute to a spectrum of adverse health effects in humans, including at low concentrations. The recognition of these food contaminants being carcinogenic, as co-occurring rather than as singularly present, has emerged from recent research. The aim of this study was to assess the potential associations of single and multiple mycotoxin exposures with renal cell carcinoma risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. METHODS: Food questionnaire data from the EPIC cohort were matched to mycotoxin food occurrence data compiled by the European Food Safety Authority (EFSA) from European Member States to assess long-term dietary mycotoxin exposures, and to associate these with the risk of renal cell carcinoma (RCC, n = 911 cases) in 450,112 EPIC participants. Potential confounding factors were taken into account. Analyses were conducted using Cox's proportional hazards regression models to compute hazard ratios (HRs) and 95% confidence intervals (95% CIs) with mycotoxin exposures expressed as µg/kg body weight/day. RESULTS: Demographic characteristics differed between the RCC cases and non-cases for body mass index, age, alcohol intake at recruitment, and other dietary factors. In addition, the mycotoxin exposure distributions showed that a large proportion of the EPIC population was exposed to some of the main mycotoxins present in European foods such as deoxynivalenol (DON) and derivatives, fumonisins, Fusarium toxins, Alternaria toxins, and total mycotoxins. Nevertheless, no statistically significant associations were observed between the studied mycotoxins and mycotoxin groups, and the risk of RCC development. CONCLUSIONS: These results show an absence of statistically significant associations between long-term dietary mycotoxin exposures and RCC risk. However, these results need to be validated in other cohorts and preferably using repeated dietary exposure measurements. In addition, more occurrence data of, e.g., citrinin and fumonisins in different food commodities and countries in the EFSA database are a prerequisite to establish a greater degree of certainty.


Subject(s)
Carcinoma, Renal Cell , Fumonisins , Kidney Neoplasms , Mycotoxins , Carcinoma, Renal Cell/chemically induced , Carcinoma, Renal Cell/epidemiology , Food Contamination/analysis , Fumonisins/analysis , Humans , Kidney Neoplasms/chemically induced , Kidney Neoplasms/epidemiology , Mycotoxins/adverse effects , Mycotoxins/analysis , Prospective Studies
15.
Front Microbiol ; 13: 988083, 2022.
Article in English | MEDLINE | ID: mdl-36110298

ABSTRACT

Mycotoxins, fungal secondary metabolites, are ubiquitously present in food commodities. Acute exposure to high levels or chronic exposure to low levels has an impact on the human body. The phase I metabolism in the human liver, performed by cytochrome P450 (CYP450) enzymes, is accountable for more than 80% of the overall metabolism of exogenous and endogenous compounds. Mycotoxins are (partially) metabolized by CYP450 enzymes. In this study, in vitro research was performed on CYP450 probes and aflatoxin B1 (AFB1), a carcinogenic mycotoxin, to obtain pharmacokinetic data on AFB1, required for further experimental work. The CYP450 probes of choice were a CYP3A4 substrate, midazolam (MDZ) and a CYP1A2 substrate, phenacetin (PH) since these are the main metabolizing phase I enzymes of AFB1. Linearity experiments were performed on the three substrates indicating that linear conditions were achieved at a microsomal protein concentration and incubation time of 0.25 mg/ml and 5 min, 0.50 mg/ml and 20 min and 0.25 mg/ml and 5 min for MDZ, PH and AFB1, respectively. The Km was determined in human liver microsomes and was estimated at 2.15 µM for MDZ, 40.0 µM for PH and 40.9 µM for AFB1. The associated V max values were 956 pmol/(mg.min) (MDZ), 856 pmol/(mg.min) (PH) and 11,536 pmol/(mg.min) (AFB1). Recombinant CYP systems were used to determine CYP450-specific Michaelis-Menten values for AFB1, leading to a CYP3A4 Km of 49.6 µM and an intersystem extrapolation factor (ISEF) corrected V max of 43.6 pmol/min/pmol P450 and a CYP1A2 Km of 58.2 µM and an ISEF corrected V max of 283 pmol/min/pmol P450. An activity adjustment factor (AAF) was calculated to account for differences between microsome batches and was used as a correction factor in the determination of the human in vivo hepatic clearance for MDZ, PH and AFB1. The hepatic blood clearance corrected for the AAF CLH,B,MDZ,AAF, CLH,B,PH,AAF CLH,B,AFB1,AAF(CYP3A4) and CLH,B,AFB1,AAF(CYP1A2) were determined in HLM at 44.1 L/h, 21.7 L/h, 40.0 L/h and 38.5 L/h. Finally, inhibition assays in HLM showed that 45% of the AFB1 metabolism was performed by CYP3A4/3A5 enzymes and 49% by CYP1A2 enzymes.

16.
Am J Clin Nutr ; 116(6): 1634-1641, 2022 12 19.
Article in English | MEDLINE | ID: mdl-36178051

ABSTRACT

BACKGROUND: Aflatoxins are toxic secondary metabolites produced by Aspergillus fungi, which are ubiquitously present in the food supplies of low- and middle-income countries. Studies of maternal aflatoxin exposure and fetal outcomes are mainly focused on size at birth and the effect on intrauterine fetal growth has not been assessed. OBJECTIVES: In the present study, we examined the association between chronic aflatoxin exposure during pregnancy and fetal growth trajectories in a rural setting in Ethiopia. METHODS: In a prospective cohort study, we enrolled 492 pregnant females, with a singleton pregnancy and before 28 wk of gestation. Serum aflatoxin B1-lysine concentration was measured using LC-tandem MS. Three rounds of ultrasound measurements were conducted to estimate fetal weight at mean ± SD gestational age weeks of 19.1 ± 3.71, 28.5 ± 3.51, and 34.5 ± 2.44. Estimated fetal weight was expressed in centiles using the International Fetal and Newborn Growth Consortium for the 21st Century (INTERGROWTH-21st) reference. We fitted a multivariable linear mixed-effects model to estimate the rate of fetal growth between aflatoxin-exposed (i.e., aflatoxin B1-lysine concentration above or equal to the limit of detection) and unexposed mothers in the study. RESULTS: Mothers had a mean ± SD age of 26.0 ± 4.58 y. The median (25th, 75th percentile) serum aflatoxin B1-lysine concentration was 12.6 (0.93, 96.9) pg/mg albumin, and aflatoxin exposure was observed in 86.6% of maternal blood samples. Eighty-five percent of the females enrolled provided at least 2 ultrasound measurements for analysis. On average, the aflatoxin-exposed group had a significantly lower change over time in fetal weight-for-gestational-age centile than the unexposed group (ß = -0.92; 95% CI: -1.77, -0.06 centiles/week; P = 0.037). CONCLUSIONS: Chronic maternal aflatoxin exposure is associated with lower fetal growth over time. Our findings emphasize the importance of nutrition-sensitive strategies to mitigate dietary aflatoxin exposure and adopting food safety measures in low-income settings, in particular during the fetal period of development.


Subject(s)
Aflatoxins , Pregnancy , Infant, Newborn , Female , Humans , Fetal Weight , Prospective Studies , Aflatoxin B1/toxicity , Mental Health , Lysine , Ethiopia , Fetal Development
17.
Article in English | MEDLINE | ID: mdl-35805375

ABSTRACT

Early-life exposure occurs during gestation through transfer to the fetus and later, during lactation. Recent monitoring data revealed that the Portuguese population is exposed to mycotoxins, including young children. This study aimed to develop a pilot study to assess the early-life exposure to mycotoxins through a mother-child cohort, and to identify the associated challenges. Participants were recruited during pregnancy (1st trimester) and followed-up in three moments of observation: 2nd trimester of pregnancy (mother), and 1st and 6th month of the child's life (mother and child), with the collection of biological samples and sociodemographic and food consumption data. The earlyMYCO pilot study enrolled 19 mother-child pairs. The analysis of biological samples from participants revealed the presence of 4 out of 15 and 5 out of 18 mycotoxins' biomarkers of exposure in urine and breast milk samples, respectively. The main aspects identified as contributors for the successful development of the cohort were the multidisciplinary and dedicated team members in healthcare units, reduced burden of participation, and the availability of healthcare units for the implementation of the fieldwork. Challenges faced, lessons learned, and suggestions were discussed as a contribution for the development of further studies in this area.


Subject(s)
Mycotoxins , Child, Preschool , Cohort Studies , Female , Humans , Mother-Child Relations , Mothers , Mycotoxins/analysis , Pilot Projects , Pregnancy
18.
Toxins (Basel) ; 14(6)2022 05 31.
Article in English | MEDLINE | ID: mdl-35737042

ABSTRACT

The sampling protocols for the official control of the levels of mycotoxins in foodstuffs are very costly and time-consuming. More efforts are needed to implement alternative sampling plans able to support official control, or to adapt the current ones. The aim of the research carried out within the European Horizon 2020 MycoKey project was to evaluate the applicability at industrial scale of the dust sampling approach to detect multiple mycotoxins in grains. To this end, two trials were performed on an EU industrial site: (i) control of the unloading of wheat from train wagons; (ii) control of the unloading of wheat from trucks. In line with previous studies, the MycoKey results indicated that dust sampling and mycotoxin analysis represent a fitness for purpose approach for non-destructive and rapid identification of wheat commodities compliant to the maximum permitted levels. Based on reviewed and newly generated results, this article discusses potential applications and limits of the dust sampling methodology, identifying future research needs.


Subject(s)
Mycotoxins , Dust/analysis , Edible Grain/chemistry , Food Contamination/analysis , Mycotoxins/analysis , Triticum
19.
Toxins (Basel) ; 14(3)2022 03 17.
Article in English | MEDLINE | ID: mdl-35324719

ABSTRACT

This work introduces an alternative workflow for the discovery of novel bacterial biocontrol agents in wheat against Fusarium head blight (FHB). Unlike the mass testing of isolate collections, we started from a diverse inoculum by extracting microbiomes from ears of field-grown plants at grain filling stage. Four distinct microbial communities were generated which were exposed to 3 14-day culture-independent experimental enrichments on detached wheat spikes infected with F. graminearum PH1. We found that one bacterial community reduced infection symptoms after 3 cycles, which was chosen to subsequently isolate bacteria through limiting dilution. All 94 isolates were tested in an in vitro and in planta assay, and a selection of 14 isolates was further tested on detached ears. The results seem to indicate that our enrichment approach resulted in bacteria with different modes-of-action in regard to FHB control. Erwinia persicina isolate C3 showed a significant reduction in disease severity (Fv/Fm), and Erwinia persicina C3 and Pseudomonas sp. B3 showed a significant reduction in fungal biomass (cGFP). However, the mycotoxin analysis of both these treatments showed no reduction in DON levels. Nevertheless, Pantoea ananatis H3 and H11 and Erwinia persicina H2 were able to reduce DON concentrations by more than 50%, although these effects were not statistically significant. Lastly, Erwinia persicina H2 also showed a significantly greater glucosylation of DON to the less phytotoxic DON-3G. The bacterial genera isolated through the enrichment cycles have been reported to dominate microbial communities that develop in open habitats, showing strong indications that the isolated bacteria can reduce the infection pressure of F. graminearum on the spike phyllosphere.


Subject(s)
Erwinia , Fusarium , Trichothecenes , Plant Diseases/microbiology , Plant Diseases/prevention & control , Triticum/microbiology
20.
Food Addit Contam Part B Surveill ; 15(2): 106-122, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35227167

ABSTRACT

Mycotoxins, being a threat to animal and human health, contribute significantly towards economic losses in the poultry sector. A liquid chromatography-mass spectrometry-based study was conducted on poultry feed samples collected from Punjab, Pakistan to evaluate the prevalence, contamination levels, and co-occurrence of multi-mycotoxins across different processed forms of the feed, types of utilities and sampling regions. All samples were found to be contaminated with aflatoxin B1 (AFB1) and fumonisin B1 (FB1). The European Commission (EC) maximum level for AFB1 in complete feedingstuffs in poultry and guidance values for FB1 and zearalenone (ZEN) were exceeded in 73%, 2%, and 14% of the contaminated samples, respectively. The corresponding median values were 39.9 µg/kg, 205 µg/kg, and 34.5 µg/kg. In addition to exceeding contamination levels, a varying co-occurrence of three to fourteen mycotoxins was observed in each of the feed samples that calls for mitigation measures to safeguard the feed and its ingredients.


Subject(s)
Mycotoxins , Aflatoxin B1 , Animal Feed/analysis , Animals , Chromatography, Liquid , Food Contamination/analysis , Mycotoxins/analysis , Pakistan , Poultry , Tandem Mass Spectrometry
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