1
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Zhao L, Li L, Liu Z, Wang X, Yang R, Luo Z, Fang X, Luan Y. Aptamer functionalized magnetic hydrophobic polymer with synergetic effect for enhanced adsorption of alternariol from wheat. Food Chem 2024; 435:137556. [PMID: 37774612 DOI: 10.1016/j.foodchem.2023.137556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 09/16/2023] [Accepted: 09/19/2023] [Indexed: 10/01/2023]
Abstract
A new adsorbent based on aptamer functionalized magnetic hydrophobic polymer (MHbPA) was developed for specific and efficient adsorption of alternariol (AOH). Through the synergistic effect of aptamer-AOH affinity and hydrophobic interaction of polymer, enhanced adsorption properties had been realized, in which AOH aptamer was the first selected through capture-SELEX with good specificity and affinity, and the targeting polymer was designed based on the hydrophobicity of AOH to increase the interaction. The proposed MHbPA demonstrated a high adsorption capacity of 187.6 ng/mg for AOH. The adsorption behavior was considered as Langmuir adsorption model and pseudo-secondary kinetic adsorption model. Notably, the adsorption of AOH in wheat powder samples could be accomplished within 10 mins with acceptable recoveries. The as designed adsorbent with synergistic effect provides new insights into the development of enhanced pretreatment materials for mycotoxin monitoring in complex food matrices with specific aptamer and targeting polymer.
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Affiliation(s)
- Liping Zhao
- Institute of Quality Standard and Testing Technology of BAAFS, Agricultural Product Quality and Safety Risk Assessment Laboratory of the Department of Agriculture, Beijing 100097, China
| | - Linsen Li
- Key Laboratory of Molecular Medicine and Biotherapy, School of Life Science, Beijing Institute of Technology, China
| | - Zheng Liu
- Beijing Institute of Food Inspection and Research (Beijing Municipal Center for Food Safety Monitoring and Risk Assessment), Beijing 100085, China
| | - Xinjie Wang
- Institute of Quality Standard and Testing Technology of BAAFS, Agricultural Product Quality and Safety Risk Assessment Laboratory of the Department of Agriculture, Beijing 100097, China
| | - Ruiqi Yang
- Institute of Quality Standard and Testing Technology of BAAFS, Agricultural Product Quality and Safety Risk Assessment Laboratory of the Department of Agriculture, Beijing 100097, China
| | - Zhaofeng Luo
- The Key Laboratory of Zhejiang Province for Aptamers and Theranostic;Aptamer Selection Center, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
| | - Xiaona Fang
- The Key Laboratory of Zhejiang Province for Aptamers and Theranostic;Aptamer Selection Center, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang 310022, China
| | - Yunxia Luan
- Institute of Quality Standard and Testing Technology of BAAFS, Agricultural Product Quality and Safety Risk Assessment Laboratory of the Department of Agriculture, Beijing 100097, China.
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Louro H, Vettorazzi A, López de Cerain A, Spyropoulou A, Solhaug A, Straumfors A, Behr AC, Mertens B, Žegura B, Fæste CK, Ndiaye D, Spilioti E, Varga E, Dubreil E, Borsos E, Crudo F, Eriksen GS, Snapkow I, Henri J, Sanders J, Machera K, Gaté L, Le Hegarat L, Novak M, Smith NM, Krapf S, Hager S, Fessard V, Kohl Y, Silva MJ, Dirven H, Dietrich J, Marko D. Hazard characterization of Alternaria toxins to identify data gaps and improve risk assessment for human health. Arch Toxicol 2024; 98:425-469. [PMID: 38147116 PMCID: PMC10794282 DOI: 10.1007/s00204-023-03636-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 11/09/2023] [Indexed: 12/27/2023]
Abstract
Fungi of the genus Alternaria are ubiquitous plant pathogens and saprophytes which are able to grow under varying temperature and moisture conditions as well as on a large range of substrates. A spectrum of structurally diverse secondary metabolites with toxic potential has been identified, but occurrence and relative proportion of the different metabolites in complex mixtures depend on strain, substrate, and growth conditions. This review compiles the available knowledge on hazard identification and characterization of Alternaria toxins. Alternariol (AOH), its monomethylether AME and the perylene quinones altertoxin I (ATX-I), ATX-II, ATX-III, alterperylenol (ALP), and stemphyltoxin III (STTX-III) showed in vitro genotoxic and mutagenic properties. Of all identified Alternaria toxins, the epoxide-bearing analogs ATX-II, ATX-III, and STTX-III show the highest cytotoxic, genotoxic, and mutagenic potential in vitro. Under hormone-sensitive conditions, AOH and AME act as moderate xenoestrogens, but in silico modeling predicts further Alternaria toxins as potential estrogenic factors. Recent studies indicate also an immunosuppressive role of AOH and ATX-II; however, no data are available for the majority of Alternaria toxins. Overall, hazard characterization of Alternaria toxins focused, so far, primarily on the commercially available dibenzo-α-pyrones AOH and AME and tenuazonic acid (TeA). Limited data sets are available for altersetin (ALS), altenuene (ALT), and tentoxin (TEN). The occurrence and toxicological relevance of perylene quinone-based Alternaria toxins still remain to be fully elucidated. We identified data gaps on hazard identification and characterization crucial to improve risk assessment of Alternaria mycotoxins for consumers and occupationally exposed workers.
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Affiliation(s)
- Henriqueta Louro
- Department of Human Genetics, National Institute of Health Dr. Ricardo Jorge (INSA) and Centre for Toxicogenomics and Human Health (ToxOmics), NOVA Medical School, Universidade Nova de Lisboa, Av. Padre Cruz, 1649-016, Lisbon, Portugal
| | - Ariane Vettorazzi
- MITOX Research Group, Department of Pharmaceutical Sciences, Faculty of Pharmacy and Nutrition, UNAV-University of Navarra, Pamplona, Spain
| | - Adela López de Cerain
- MITOX Research Group, Department of Pharmaceutical Sciences, Faculty of Pharmacy and Nutrition, UNAV-University of Navarra, Pamplona, Spain
| | - Anastasia Spyropoulou
- Laboratory of Toxicological Control of Pesticides, Scientific Directorate of Pesticides' Control and Phytopharmacy, Benaki Phytopathological Institute, 145 61, Attica, Greece
| | - Anita Solhaug
- Norwegian Veterinary Institute, PO Box 64, 1431, Ås, Norway
| | | | - Anne-Cathrin Behr
- Department Food Safety, BfR, German Federal Institute for Risk Assessment, Max-Dohrnstraße 8-10, 10589, Berlin, Germany
| | - Birgit Mertens
- Department of Chemical and Physical Health Risks, Sciensano, Brussels, Belgium
| | - Bojana Žegura
- Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna Pot 111, 1000, Ljubljana, Slovenia
| | | | - Dieynaba Ndiaye
- INRS, Institut National de Recherche et de Sécurité pour la Prévention des accidents du travail et des maladies professionnelles, Rue du Morvan, CS 60027, 54519, Vandœuvre Lès Nancy Cedex, France
| | - Eliana Spilioti
- Laboratory of Toxicological Control of Pesticides, Scientific Directorate of Pesticides' Control and Phytopharmacy, Benaki Phytopathological Institute, 145 61, Attica, Greece
| | - Elisabeth Varga
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
- Food Hygiene and Technology, University of Veterinary Medicine, Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Estelle Dubreil
- Toxicology of Contaminants Unit, Fougères Laboratory, French Agency for Food, Environmental and Occupational Health and Safety, 10 B rue Claude Bourgelat, 35306, Fougères, France
| | - Eszter Borsos
- Food Hygiene and Technology, University of Veterinary Medicine, Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Francesco Crudo
- Food Hygiene and Technology, University of Veterinary Medicine, Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | | | - Igor Snapkow
- Department of Chemical Toxicology, Norwegian Institute of Public Health, Lovisenberggate 8, 0456, Oslo, Norway
| | - Jérôme Henri
- Toxicology of Contaminants Unit, Fougères Laboratory, French Agency for Food, Environmental and Occupational Health and Safety, 10 B rue Claude Bourgelat, 35306, Fougères, France
| | - Julie Sanders
- Department of Chemical and Physical Health Risks, Sciensano, Brussels, Belgium
| | - Kyriaki Machera
- Laboratory of Toxicological Control of Pesticides, Scientific Directorate of Pesticides' Control and Phytopharmacy, Benaki Phytopathological Institute, 145 61, Attica, Greece
| | - Laurent Gaté
- INRS, Institut National de Recherche et de Sécurité pour la Prévention des accidents du travail et des maladies professionnelles, Rue du Morvan, CS 60027, 54519, Vandœuvre Lès Nancy Cedex, France
| | - Ludovic Le Hegarat
- Toxicology of Contaminants Unit, Fougères Laboratory, French Agency for Food, Environmental and Occupational Health and Safety, 10 B rue Claude Bourgelat, 35306, Fougères, France
| | - Matjaž Novak
- Department of Genetic Toxicology and Cancer Biology, National Institute of Biology, Večna Pot 111, 1000, Ljubljana, Slovenia
| | - Nicola M Smith
- Department of Chemical Toxicology, Norwegian Institute of Public Health, Lovisenberggate 8, 0456, Oslo, Norway
| | - Solveig Krapf
- Norwegian Veterinary Institute, PO Box 64, 1431, Ås, Norway
| | - Sonja Hager
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Valérie Fessard
- Toxicology of Contaminants Unit, Fougères Laboratory, French Agency for Food, Environmental and Occupational Health and Safety, 10 B rue Claude Bourgelat, 35306, Fougères, France
| | - Yvonne Kohl
- Fraunhofer Institute for Biomedical Engineering IBMT, Joseph-Von-Fraunhofer-Weg 1, 66280, Sulzbach, Germany
| | - Maria João Silva
- Department of Human Genetics, National Institute of Health Dr. Ricardo Jorge (INSA) and Centre for Toxicogenomics and Human Health (ToxOmics), NOVA Medical School, Universidade Nova de Lisboa, Av. Padre Cruz, 1649-016, Lisbon, Portugal
| | - Hubert Dirven
- Department of Chemical Toxicology, Norwegian Institute of Public Health, Lovisenberggate 8, 0456, Oslo, Norway
| | - Jessica Dietrich
- Department Safety in the Food Chain, BfR, German Federal Institute for Risk Assessment, Max-Dohrn-Straße 8-10, 10589, Berlin, Germany
| | - Doris Marko
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria.
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Marin DE, Taranu I. Using In Silico Approach for Metabolomic and Toxicity Prediction of Alternariol. Toxins (Basel) 2023; 15:421. [PMID: 37505690 PMCID: PMC10467053 DOI: 10.3390/toxins15070421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/26/2023] [Accepted: 06/27/2023] [Indexed: 07/29/2023] Open
Abstract
Alternariol is a metabolite produced by Alternaria fungus that can contaminate a variety of food and feed materials. The objective of the present paper was to provide a prediction of Phase I and II metabolites of alternariol and a detailed ADME/Tox profile for alternariol and its metabolites using an in silico working model based on the MetaTox, SwissADME, pKCMS, and PASS online computational programs. A number of 12 metabolites were identified as corresponding to the metabolomic profile of alternariol. ADME profile for AOH and predicted metabolites indicated a moderate or high intestinal absorption probability but a low probability to penetrate the blood-brain barrier. In addition to cytotoxic, mutagenic, carcinogenic, and endocrine disruptor effects, the computational model has predicted other toxicological endpoints for the analyzed compounds, such as vascular toxicity, haemato-toxicity, diarrhea, and nephrotoxicity. AOH and its metabolites have been predicted to act as a substrate for different isoforms of phase I and II drug-metabolizing enzymes and to interact with the response to oxidative stress. In conclusion, in silico methods can represent a viable alternative to in vitro and in vivo tests for the prediction of mycotoxins metabolism and toxicity.
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Affiliation(s)
| | - Ionelia Taranu
- National Research and Development Institute for Biology and Animal Nutrition, 077015 Balotesti, Romania;
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Aichinger G, Pahlke G, Puntscher H, Groestlinger J, Grabher S, Braun D, Tillmann K, Plasenzotti R, Del Favero G, Warth B, Höger H, Marko D. Markers for DNA damage are induced in the rat colon by the Alternaria toxin altertoxin-II, but not a complex extract of cultured Alternaria alternata. FRONTIERS IN TOXICOLOGY 2022; 4:977147. [PMID: 36353200 PMCID: PMC9638006 DOI: 10.3389/ftox.2022.977147] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 10/12/2022] [Indexed: 01/19/2024] Open
Abstract
Mycotoxins produced by Alternaria spp. act genotoxic in cell-based studies, but data on their toxicity in vivo is scarce and urgently required for risk assessment. Thus, male Sprague-Dawley rats received single doses of a complex Alternaria toxin extract (CE; 50 mg/kg bw), altertoxin II (ATX-II; 0.21 mg/kg bw) or vehicle by gavage, one of the most genotoxic metabolites in vitro and were sacrificed after 3 or 24 h, respectively. Using SDS-PAGE/Western Blot, a significant increase of histone 2a.X phosphorylation and depletion of the native protein was observed for rats that were exposed to ATX-II for 24 h. Applying RT-PCR array technology we identified genes of interest for qRT-PCR testing, which in turn confirmed an induction of Rnf8 transcription in the colon of rats treated with ATX-II for 3 h and CE for 24 h. A decrease of Cdkn1a transcription was observed in rats exposed to ATX-II for 24 h, possibly indicating tissue repair after chemical injury. In contrast to the observed response in the colon, no markers for genotoxicity were induced in the liver of treated animals. We hereby provide the first report of ATX-II as a genotoxicant in vivo. Deviating results for similar concentrations of ATX-II in a natural Alternaria toxin mixture argue for substantial mixture effects.
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Affiliation(s)
- Georg Aichinger
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
- Laboratory of Toxicology, Department of Health Science and Technology, ETH Zurich, Switzerland
| | - Gudrun Pahlke
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Hannes Puntscher
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Julia Groestlinger
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Stephanie Grabher
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Dominik Braun
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Katharina Tillmann
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Roberto Plasenzotti
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Giorgia Del Favero
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
- Core Facility Multimodal Imaging, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Benedikt Warth
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Harald Höger
- Center for Biomedical Research, Medical University of Vienna, Vienna, Austria
| | - Doris Marko
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Vienna, Austria
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5
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Aichinger G. Natural Dibenzo-α-Pyrones: Friends or Foes? Int J Mol Sci 2021; 22:ijms222313063. [PMID: 34884865 PMCID: PMC8657677 DOI: 10.3390/ijms222313063] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 12/17/2022] Open
Abstract
Natural dibenzo-α-pyrones (DAPs) can be viewed from two opposite angles. From one angle, the gastrointestinal metabolites urolithins are regarded as beneficial, while from the other, the emerging mycotoxin alternariol and related fungal metabolites are evaluated critically with regards to potential hazardous effects. Thus, the important question is: can the structural characteristics of DAP subgroups be held responsible for distinct bioactivity patterns? If not, certain toxicological and/or pharmacological aspects of natural DAPs might yet await elucidation. Thus, this review focuses on comparing published data on the two groups of natural DAPs regarding both adverse and beneficial effects on human health. Literature on genotoxic, estrogenic, endocrine-disruptive effects, as well as on the induction of the cellular anti-oxidative defense system, anti-inflammatory properties, the inhibition of kinases, the activation of mitophagy and the induction of autophagy, is gathered and critically reviewed. Indeed, comparing published data suggests similar bioactivity profiles of alternariol and urolithin A. Thus, the current stratification into hazardous Alternaria toxins and healthy urolithins seems debatable. An extrapolation of bioactivities to the other DAP sub-class could serve as a promising base for further research. Conclusively, urolithins should be further evaluated toward high-dose toxicity, while alternariol derivatives could be promising chemicals for the development of therapeutics.
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Affiliation(s)
- Georg Aichinger
- Laboratory of Toxicology, Department of Health Sciences and Technology, ETH Zurich, 8092 Zurich, Switzerland
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Wang S, Gao H, Wei Z, Zhou J, Ren S, He J, Luan Y, Lou X. Shortened and multivalent aptamers for ultrasensitive and rapid detection of alternariol in wheat using optical waveguide sensors. Biosens Bioelectron 2021; 196:113702. [PMID: 34655971 DOI: 10.1016/j.bios.2021.113702] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 10/05/2021] [Accepted: 10/09/2021] [Indexed: 12/11/2022]
Abstract
Alternariol (AOH) is one of the common mycotoxins existing in a variety of foods at low level. Aptamers hold great promise for the development of sensitive and rapid aptasensors, but suffer from the excessive length and the difficulty in identification of critical binding domains (CBDs). In this study, the 5 nt CBD of the original 59-nt AOH aptamer (AOH-59, KD = 423 nM) was identified to be a 'C' bulge in between two A-T base pairs. AOH-59 was successfully shortened to a 23 nt aptamer (AOH 6C, KD = 701 nM). A 30 nt bivalent aptamer B-2-3 (KD = 445 nM) and a 39 nt trivalent aptamer T-2-3 (KD = 274 nM) were obtained by simply incorporating one or two CBDs into AOH 6C. The AOH 6C-, B-2-3-, and T-2-3-based optical waveguide aptasensors possessed the unprecedented detection of limits (LODs, S/N = 3) of 42 ± 3, 6 ± 1 and 2 ± 1 fM, respectively. Using the AOH 6C-based sensor as an example, we further demonstrated the detection of AOH spiked in wheat powder with a LOD of 37 pg/g, 20-230-fold lower than those achieved by ELISAs. The sensor was capable for 35 times 2-min regeneration and the assay time including the extraction of AOH from wheat was only about 1 h. We not only devised the first aptasensors for AOH detection, but also provided a simple strategy to design multivalent aptamers for small molecule targets.
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Affiliation(s)
- Shuo Wang
- Department of Chemistry, Capital Normal University, Xisanhuan North Road. 105, Beijing 100048, China
| | - Hualong Gao
- Department of Chemistry, Capital Normal University, Xisanhuan North Road. 105, Beijing 100048, China
| | - Zhenzhe Wei
- Department of Chemistry, Capital Normal University, Xisanhuan North Road. 105, Beijing 100048, China
| | - Jianshuo Zhou
- Department of Chemistry, Capital Normal University, Xisanhuan North Road. 105, Beijing 100048, China
| | - Shang Ren
- Department of Chemistry, Capital Normal University, Xisanhuan North Road. 105, Beijing 100048, China
| | - Junlin He
- State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing, 100850, China.
| | - Yunxia Luan
- Beijing Research Center for Agricultural Standards and Testing, Agricultural Product Quality and Safety Risk Assessment Laboratory of the Department of Agriculture, Beijing Municipal Key Laboratory of Agriculture Environment Monitoring, Beijing Academy of Agriculture and Forestry Sciences, Middle Road of Shuguang Huayuan No.9, Beijing 100097, China.
| | - Xinhui Lou
- Department of Chemistry, Capital Normal University, Xisanhuan North Road. 105, Beijing 100048, China.
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Aichinger G, Del Favero G, Warth B, Marko D. Alternaria toxins-Still emerging? Compr Rev Food Sci Food Saf 2021; 20:4390-4406. [PMID: 34323368 DOI: 10.1111/1541-4337.12803] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 06/18/2021] [Accepted: 06/19/2021] [Indexed: 12/13/2022]
Abstract
Alternaria molds are known to cause the contamination of food with their secondary metabolites, a chemically very heterogeneous group of compounds. Yet, after decades of research on the occurrence and the toxicity of Alternaria toxins in academia, no regulation has been implemented yet, thus leaving these potential food contaminants in the status of so-called "emerging mycotoxins". However, research on this topic has been far from static, leading to the European Food Safety Authority repeatedly calling for more data on the occurrence and toxicity of genotoxic metabolites such as alternariol (AOH) and its monomethyl ether (AME). To give an overview on recent developments in the field, this comprehensive review summarizes published data and addresses current challenges arising from the chemical complexity of Alternaria's metabolome, mixture effects and the emergence of novel biological targets like cell membranes or the interaction with different receptors. Besides toxicodynamics, we review recent research on toxicokinetics, including the first in vivo studies which incorporated the rarely investigated-but highly genotoxic-perylene quinones. Furthermore, a particular focus lies on the advances of liquid chromatography/tandem mass spectrometry (LC-MS/MS)-based analytical tools for determining a broader spectrum of Alternaria toxins including modified/masked forms and assessing exposure via human biomonitoring (HBM).
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Affiliation(s)
- Georg Aichinger
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Wien, Austria
| | - Giorgia Del Favero
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Wien, Austria
| | - Benedikt Warth
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Wien, Austria
| | - Doris Marko
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Wien, Austria
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Chen A, Mao X, Sun Q, Wei Z, Li J, You Y, Zhao J, Jiang G, Wu Y, Wang L, Li Y. Alternaria Mycotoxins: An Overview of Toxicity, Metabolism, and Analysis in Food. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:7817-7830. [PMID: 34250809 DOI: 10.1021/acs.jafc.1c03007] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The genus Alternaria is widely distributed in the environment. Numerous species of the genus Alternaria can produce a variety of toxic secondary metabolites, called Alternaria mycotoxins. In this review, natural occurrence, toxicity, metabolism, and analytical methods are introduced. The contamination of these toxins in foodstuffs is ubiquitous, and most of these metabolites present genotoxic and cytotoxic effects. Moreover, Alternaria toxins are mainly hydroxylated to catechol metabolites and combined with sulfate and glucuronic acid in in vitro arrays. A more detailed summary of the metabolism of Alternaria toxins is presented in this work. To effectively detect and determine the mycotoxins in food, analytical methods with high sensitivity and good accuracy are also reviewed. This review will guide the formulation of maximum residue limit standards in the future, covering both toxicity and metabolic mechanism of Alternaria toxins.
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Affiliation(s)
- Anqi Chen
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
| | - Xin Mao
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
| | - Qinghui Sun
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
| | - Zixuan Wei
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
| | - Juan Li
- Department of Chemical and Biochemical Engineering, University of Western Ontario, London, Ontario N6A 5B9, Canada
| | - Yanli You
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
| | - Jiqiang Zhao
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China
| | - Yongning Wu
- NHC Key Laboratory of Food Safety Risk Assessment, Chinese Academy of Medical Science Research Unit (2019RU014), China National Center for Food Safety Risk Assessment, Beijing 100017, People's Republic of China
| | - Liping Wang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, People's Republic of China
| | - Yanshen Li
- College of Life Science, Yantai University, Yantai, Shandong 264005, People's Republic of China
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9
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Crudo F, Barilli A, Mena P, Rotoli BM, Rio DD, Dall'Asta C, Dellafiora L. An in vitro study on the transport and phase II metabolism of the mycotoxin alternariol in combination with the structurally related gut microbial metabolite urolithin C. Toxicol Lett 2021; 340:15-22. [PMID: 33421552 DOI: 10.1016/j.toxlet.2021.01.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/29/2020] [Accepted: 01/03/2021] [Indexed: 01/20/2023]
Abstract
Alternariol is a mycotoxin produced by Alternaria spp. relevant to the food safety area due to its abundance in certain foods. The shortage of data on its toxicology, also as a part of chemical mixtures, prevents setting regulation to limit its abundance in food. To extend knowledge on the possible mechanisms underpinning alternariol toxicology in chemical mixtures, this work assessed the effects of urolithin C, a structurally related gut ellagitannin-derived metabolite, on its absorption and phase II metabolism in a monolayer of Caco-2 cells. A computational study was also used to provide a mechanistic explanation for the results obtained. Urolithin C influenced transport and phase II metabolism of alternariol with a late reduction of transport to the basolateral compartment. Moreover, it caused an early effect in terms of accumulation of alternariol glucuronides in the basolateral compartment, followed by a late reduction of glucuronides in both compartments. Concerning alternariol sulfates, the data collected pointed to a possible competition of urolithin C for the sulfotransferases resulting in a reduced production of alternariol sulfates. Our results provide a compelling line-of-evidence pointing to the need to systematically tackle the evaluation of mycotoxin toxicity in the context of chemical mixture.
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Affiliation(s)
- Francesco Crudo
- Department of Food and Drug, University of Parma, Area Parco Delle Scienze 27/A, 43124 Parma, Italy
| | - Amelia Barilli
- Department of Medicine and Surgery (DiMeC), University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - Pedro Mena
- Human Nutrition Unit, Department of Food and Drug, University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - Bianca Maria Rotoli
- Department of Medicine and Surgery (DiMeC), University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - Daniele Del Rio
- Human Nutrition Unit, Department of Veterinary Science, University of Parma, Via Volturno 39, 43125, Parma, Italy
| | - Chiara Dall'Asta
- Department of Food and Drug, University of Parma, Area Parco Delle Scienze 27/A, 43124 Parma, Italy
| | - Luca Dellafiora
- Department of Food and Drug, University of Parma, Area Parco Delle Scienze 27/A, 43124 Parma, Italy.
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Tran VN, Viktorová J, Ruml T. Mycotoxins: Biotransformation and Bioavailability Assessment Using Caco-2 Cell Monolayer. Toxins (Basel) 2020; 12:E628. [PMID: 33008111 PMCID: PMC7601793 DOI: 10.3390/toxins12100628] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/24/2020] [Accepted: 09/18/2020] [Indexed: 12/17/2022] Open
Abstract
The determination of mycotoxins content in food is not sufficient for the prediction of their potential in vivo cytotoxicity because it does not reflect their bioavailability and mutual interactions within complex matrices, which may significantly alter the toxic effects. Moreover, many mycotoxins undergo biotransformation and metabolization during the intestinal absorption process. Biotransformation is predominantly the conversion of mycotoxins meditated by cytochrome P450 and other enzymes. This should transform the toxins to nontoxic metabolites but it may possibly result in unexpectedly high toxicity. Therefore, the verification of biotransformation and bioavailability provides valuable information to correctly interpret occurrence data and biomonitoring results. Among all of the methods available, the in vitro models using monolayer formed by epithelial cells from the human colon (Caco-2 cell) have been extensively used for evaluating the permeability, bioavailability, intestinal transport, and metabolism of toxic and biologically active compounds. Here, the strengths and limitations of both in vivo and in vitro techniques used to determine bioavailability are reviewed, along with current detailed data about biotransformation of mycotoxins. Furthermore, the molecular mechanism of mycotoxin effects is also discussed regarding the disorder of intestinal barrier integrity induced by mycotoxins.
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Affiliation(s)
| | | | - Tomáš Ruml
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 166 28 Prague 6, Czech Republic; (V.N.T.); (J.V.)
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Alternaria alternata Toxins Synergistically Activate the Aryl Hydrocarbon Receptor Pathway In Vitro. Biomolecules 2020; 10:biom10071018. [PMID: 32659980 PMCID: PMC7407958 DOI: 10.3390/biom10071018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 06/28/2020] [Accepted: 06/30/2020] [Indexed: 02/06/2023] Open
Abstract
Alternaria molds simultaneously produce a large variety of mycotoxins, of which several were previously reported to induce enzymes of phase I metabolism through aryl hydrocarbon receptor activation. Thus, we investigated the potential of naturally occurring Alternaria toxin mixtures to induce Cytochrome P450 (CYP) 1A1/1A2/1B1 activity. Two variants of an extract from cultured Alternaria alternata, as well as the toxins alternariol (AOH), alternariol monomethyl ether (AME), altertoxin I (ATX-I), and altertoxin II (ATX-II), were tested singularly and in binary mixtures applying the 7-ethoxy-resorufin-O-deethylase (EROD) assay in MCF-7 breast cancer cells. Sub-cytotoxic concentrations of the two toxin mixtures, as well as ATX-I, ATX-II and AOH, exhibited dose-dependent enhancements of CYP 1 activity. ATX-I and ATX-II interacted synergistically in this respect, demonstrating the two perylene quinones as major contributors to the extract’s potential. Binary mixtures between AOH and the two altertoxins respectively exhibited concentration-dependent antagonistic as well as synergistic combinatory effects. Notably, AME showed no efficacy towards EROD enzyme activity or impact on other toxins’ efficacy. Hence, this study provides insights into synergistic and other combinatory effects of Alternaria toxins in natural co-occurrence scenarios in the context of AhR signalling pathway activation in breast cancer cells.
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Scheibenzuber S, Hoffmann T, Effenberger I, Schwab W, Asam S, Rychlik M. Enzymatic Synthesis of Modified Alternaria Mycotoxins Using a Whole-Cell Biotransformation System. Toxins (Basel) 2020; 12:toxins12040264. [PMID: 32326012 PMCID: PMC7232528 DOI: 10.3390/toxins12040264] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 02/06/2023] Open
Abstract
Reference standards for Alternaria mycotoxins are rarely available, especially the modified mycotoxins alternariol-3-glucoside (AOH-3-G), alternariol-9-glucoside (AOH-9-G), and alternariol monomethylether-3-glucoside (AME-3-G). To obtain these three glucosides as analytical standards for method development and method validation, alternariol and alternariol monomethylether were enzymatically glycosylated in a whole-cell biotransformation system using a glycosyltransferase from strawberry (Fragaria x ananassa), namely UGT71A44, expressed in Escherichia coli (E. coli). The formed glucosides were isolated, purified, and structurally characterized. The exact amount of the isolated compounds was determined using high-performance liquid chromatography with UV-detection (HPLC-UV) and quantitative nuclear resonance spectroscopy (qNMR). This method has proved to be highly effective with biotransformation rates of 58% for AOH-3-G, 5% for AOH-9-G, and 24% for AME-3-G.
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Affiliation(s)
- Sophie Scheibenzuber
- Chair of Analytical Food Chemistry, Technical University of Munich, Maximus-von-Imhof Forum 2, 85354 Freising, Germany; (S.S.); (S.A.)
| | - Thomas Hoffmann
- Biotechnology of Natural Products, Technical University of Munich, Liesel-Beckmann-Straße 1, 85354 Freising, Germany; (T.H.); (W.S.)
| | | | - Wilfried Schwab
- Biotechnology of Natural Products, Technical University of Munich, Liesel-Beckmann-Straße 1, 85354 Freising, Germany; (T.H.); (W.S.)
| | - Stefan Asam
- Chair of Analytical Food Chemistry, Technical University of Munich, Maximus-von-Imhof Forum 2, 85354 Freising, Germany; (S.S.); (S.A.)
| | - Michael Rychlik
- Chair of Analytical Food Chemistry, Technical University of Munich, Maximus-von-Imhof Forum 2, 85354 Freising, Germany; (S.S.); (S.A.)
- Correspondence:
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13
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Tran VN, Viktorova J, Augustynkova K, Jelenova N, Dobiasova S, Rehorova K, Fenclova M, Stranska-Zachariasova M, Vitek L, Hajslova J, Ruml T. In Silico and In Vitro Studies of Mycotoxins and Their Cocktails; Their Toxicity and Its Mitigation by Silibinin Pre-Treatment. Toxins (Basel) 2020; 12:E148. [PMID: 32121188 PMCID: PMC7150870 DOI: 10.3390/toxins12030148] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 02/21/2020] [Accepted: 02/25/2020] [Indexed: 12/31/2022] Open
Abstract
Mycotoxins found in randomly selected commercial milk thistle dietary supplement were evaluated for their toxicity in silico and in vitro. Using in silico methods, the basic physicochemical, pharmacological, and toxicological properties of the mycotoxins were predicted using ACD/Percepta. The in vitro cytotoxicity of individual mycotoxins was determined in mouse macrophage (RAW 264.7), human hepatoblastoma (HepG2), and human embryonic kidney (HEK 293T) cells. In addition, we studied the bioavailability potential of mycotoxins and silibinin utilizing an in vitro transwell system with differentiated human colon adenocarcinoma cells (Caco-2) simulating mycotoxin transfer through the intestinal epithelial barrier. The IC50 values for individual mycotoxins in studied cells were in the biologically relevant ranges as follows: 3.57-13.37 nM (T-2 toxin), 5.07-47.44 nM (HT-2 toxin), 3.66-17.74 nM (diacetoxyscirpenol). Furthermore, no acute toxicity was obtained for deoxynivalenol, beauvericin, zearalenone, enniatinENN-A, enniatin-A1, enniatin-B, enniatin-B1, alternariol, alternariol-9-methyl ether, tentoxin, and mycophenolic acid up to the 50 nM concentration. The acute toxicity of these mycotoxins in binary combinations exhibited antagonistic effects in the combinations of T-2 with DON, ENN-A1, or ENN-B, while the rest showed synergistic or additive effects. Silibinin had a significant protective effect against both the cytotoxicity of three mycotoxins (T-2 toxin, HT-2 toxin, DAS) and genotoxicity of AME, AOH, DON, and ENNs on HEK 293T. The bioavailability results confirmed that AME, DAS, ENN-B, TEN, T-2, and silibinin are transported through the epithelial cell layer and further metabolized. The bioavailability of silibinin is very similar to mycotoxins poor penetration.
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Affiliation(s)
- Van Nguyen Tran
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
| | - Jitka Viktorova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
| | - Katerina Augustynkova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
| | - Nikola Jelenova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
| | - Simona Dobiasova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
| | - Katerina Rehorova
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
| | - Marie Fenclova
- Department of Food Analysis and Nutrition, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (M.F.); (M.S.-Z.); (J.H.)
| | - Milena Stranska-Zachariasova
- Department of Food Analysis and Nutrition, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (M.F.); (M.S.-Z.); (J.H.)
| | - Libor Vitek
- First Faculty of Medicine, Charles University, Katerinska 32, 12108 Prague 2, Czech Republic;
- Faculty General Hospital, U Nemocnice 2, 12808 Praha 2, Czech Republic
| | - Jana Hajslova
- Department of Food Analysis and Nutrition, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (M.F.); (M.S.-Z.); (J.H.)
| | - Tomas Ruml
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Technicka 3, 16628 Prague 6, Czech Republic; (V.N.T.); (J.V.); (K.A.); (N.J.); (S.D.); (K.R.)
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14
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Bioavailability, metabolism, and excretion of a complex Alternaria culture extract versus altertoxin II: a comparative study in rats. Arch Toxicol 2019; 93:3153-3167. [DOI: 10.1007/s00204-019-02575-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 09/17/2019] [Indexed: 12/22/2022]
Abstract
Abstract
Despite the frequent infection of agricultural crops by Alternaria spp., their toxic secondary metabolites and potential food contaminants lack comprehensive metabolic characterization. In this study, we investigated their bioavailability, metabolism, and excretion in vivo. A complex Alternaria culture extract (50 mg/kg body weight) containing 11 known toxins and the isolated lead toxin altertoxin II (0.7 mg/kg body weight) were administered per gavage to groups of 14 Sprague Dawley rats each. After 3 h and 24 h, plasma, urine and feces were collected to determine toxin recoveries. For reliable quantitation, an LC–MS/MS method for the simultaneous detection of 20 Alternaria toxins and metabolites was developed and optimized for either biological matrix. The obtained results demonstrated efficient excretion of alternariol (AOH) and its monomethyl ether (AME) via feces (> 89%) and urine (> 2.6%) after 24 h, while the majority of tenuazonic acid was recovered in urine (20 and 87% after 3 and 24 h, respectively). Moreover, modified forms of AOH and AME were identified in urine and fecal samples confirming both, mammalian phase-I (4-hydroxy-AOH) and phase-II (sulfates) biotransformation in vivo. Despite the comparably high doses, perylene quinones were recovered only at very low levels (altertoxin I, alterperylenol, < 0.06% in urine and plasma, < 5% in feces) or not at all (highly genotoxic, epoxide-holding altertoxin II, stemphyltoxin III). Interestingly, altertoxin I was detected in all matrices of rats receiving altertoxin II and suggests enzymatic de-epoxidation in vivo. In conclusion, the present study contributes valuable information to advance our understanding of the emerging Alternaria mycotoxins and their relevance on food safety.
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15
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First insights into Alternaria multi-toxin in vivo metabolism. Toxicol Lett 2019; 301:168-178. [DOI: 10.1016/j.toxlet.2018.10.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 09/14/2018] [Accepted: 10/08/2018] [Indexed: 11/19/2022]
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16
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Hessel-Pras S, Kieshauer J, Roenn G, Luckert C, Braeuning A, Lampen A. In vitro characterization of hepatic toxicity of Alternaria toxins. Mycotoxin Res 2018; 35:157-168. [PMID: 30552586 DOI: 10.1007/s12550-018-0339-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 11/15/2018] [Accepted: 12/04/2018] [Indexed: 10/27/2022]
Abstract
Alternaria mycotoxins are secondary fungal metabolites which can contaminate food and feed. They are produced by Alternaria species with alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA), and tentoxin (TEN) as the main representatives for Alternaria mycotoxins in food. Once passing the intestinal barrier, Alternaria toxins can reach the liver to exert yet uncharacterized molecular effects. Therefore, hepatic in vitro systems were used to examine selected Alternaria mycotoxins for their induction of metabolism-dependent cytotoxicity, phosphorylation of the histone H2AX as a surrogate marker for DNA double-strand breaks, and relevant marker genes for hepatotoxicity. Analysis of cell viability as well as the induction of H2AX phosphorylation in the hepatocarcinoma cell line HepG2 revealed a detoxification of 100 μmol/l AME and AOH by pre-treatment with S9 liver homogenate as shown by a decrease in cytotoxicity and H2AX histone phosphorylation to levels observed in control cells. Concentrations up to 100 μmol/l TeA and TEN did not induce H2AX phosphorylation whether metabolized or not. In the metabolically competent human hepatoma cell line HepaRG, no cytotoxicity of Alternaria toxins occurred even at high concentrations up to 100 μmol/l, which indicates a low cytotoxic potential. Induction of gene expression associated with liver toxicity was analyzed by quantitative real-time PCR using a specific hepatotoxicity PCR array in HepaRG cells: here, an evidence was found that 50 μmol/l of AOH, AME, TeA, and TEN might be associated with hepatotoxic effects, necrosis, and the development of diseases like cholestasis and phospholipidosis.
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Affiliation(s)
- Stefanie Hessel-Pras
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany.
| | - Janine Kieshauer
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Giana Roenn
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Claudia Luckert
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Albert Braeuning
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
| | - Alfonso Lampen
- Department of Food Safety, German Federal Institute for Risk Assessment, Max-Dohrn-Str. 8-10, 10589, Berlin, Germany
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17
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Zwickel T, Kahl SM, Rychlik M, Müller MEH. Chemotaxonomy of Mycotoxigenic Small-Spored Alternaria Fungi - Do Multitoxin Mixtures Act as an Indicator for Species Differentiation? Front Microbiol 2018; 9:1368. [PMID: 30018598 PMCID: PMC6037717 DOI: 10.3389/fmicb.2018.01368] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 06/06/2018] [Indexed: 11/13/2022] Open
Abstract
Necrotrophic as well as saprophytic small-spored Alternaria (A.) species are annually responsible for major losses of agricultural products, such as cereal crops, associated with the contamination of food and feedstuff with potential health-endangering Alternaria toxins. Knowledge of the metabolic capabilities of different species-groups to form mycotoxins is of importance for a reliable risk assessment. 93 Alternaria strains belonging to the four species groups Alternaria tenuissima, A. arborescens, A. alternata, and A. infectoria were isolated from winter wheat kernels harvested from fields in Germany and Russia and incubated under equal conditions. Chemical analysis by means of an HPLC-MS/MS multi-Alternaria-toxin-method showed that 95% of all strains were able to form at least one of the targeted 17 non-host specific Alternaria toxins. Simultaneous production of up to 15 (modified) Alternaria toxins by members of the A. tenuissima, A. arborescens, A. alternata species-groups and up to seven toxins by A. infectoria strains was demonstrated. Overall tenuazonic acid was the most extensively formed mycotoxin followed by alternariol and alternariol mono methylether, whereas altertoxin I was the most frequently detected toxin. Sulfoconjugated modifications of alternariol, alternariol mono methylether, altenuisol and altenuene were frequently determined. Unknown perylene quinone derivatives were additionally detected. Strains of the species-group A. infectoria could be segregated from strains of the other three species-groups due to significantly lower toxin levels and the specific production of infectopyrone. Apart from infectopyrone, alterperylenol was also frequently produced by 95% of the A. infectoria strains. Neither by the concentration nor by the composition of the targeted Alternaria toxins a differentiation between the species-groups A. alternata, A. tenuissima and A. arborescens was possible.
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Affiliation(s)
- Theresa Zwickel
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
- Chair of Analytical Food Chemistry, Technical University of Munich, Munich, Germany
| | - Sandra M. Kahl
- Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany
- Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Michael Rychlik
- Chair of Analytical Food Chemistry, Technical University of Munich, Munich, Germany
| | - Marina E. H. Müller
- Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany
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18
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Righetti L, Bergmann A, Galaverna G, Rolfsson O, Paglia G, Dall'Asta C. Ion mobility-derived collision cross section database: Application to mycotoxin analysis. Anal Chim Acta 2018. [PMID: 29523251 DOI: 10.1016/j.aca.2018.01.047] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The recent hyphenation of ion mobility spectrometry (IMS) with high resolution mass spectrometry (HRMS) has risen as a powerful technique for both targeted and non-targeted screening, reducing background noise and allowing separation of isomeric and isobaric compounds. Nevertheless, such an approach remains largely unexplored in food safety applications, such as mycotoxin analysis. To implement ion mobility in routinely MS-based mycotoxin workflows, searchable databases with collusion cross section (CCS) values and accurate mass-values are required. This paper provides for the first time a traveling-wave IMS (TWIMS)-derived CCS database for mycotoxins, including more than 100 CCS values. The measurements showed high reproducibility (RSD < 2%) across different instrumental conditions as well as several complex cereal matrices, showing a mean inter-matrix precision of RSD <0.9%. As a proof of concept, the database was applied to the analysis of several spiked as well as naturally incurred cereal-based samples. In addition, the effect of adducts on the drift time was studied in a series of mycotoxins in order to understand potential deviations from expected drift time behaviors. Overall, our study confirmed that CCS values represent a physicochemical property that can be used alongside the traditional molecular identifiers of precursor ion accurate mass, fragment ions, isotopic pattern, and retention time.
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Affiliation(s)
- Laura Righetti
- Department of Food Science, University of Parma, Viale delle Scienze 17/A, I-43124 Parma, Italy
| | - Andreas Bergmann
- Center for Systems Biology, Medical Department, University of Iceland, Sturlugata 8, 101 Reykjavik, Iceland
| | - Gianni Galaverna
- Department of Food Science, University of Parma, Viale delle Scienze 17/A, I-43124 Parma, Italy
| | - Ottar Rolfsson
- Center for Systems Biology, Medical Department, University of Iceland, Sturlugata 8, 101 Reykjavik, Iceland
| | - Giuseppe Paglia
- Center of Biomedicine, European Academy of Bolzano/Bozen, Via Galvani 31, Bolzano 39100, Italy
| | - Chiara Dall'Asta
- Department of Food Science, University of Parma, Viale delle Scienze 17/A, I-43124 Parma, Italy.
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Righetti L, Fenclova M, Dellafiora L, Hajslova J, Stranska-Zachariasova M, Dall'Asta C. High resolution-ion mobility mass spectrometry as an additional powerful tool for structural characterization of mycotoxin metabolites. Food Chem 2017; 245:768-774. [PMID: 29287439 DOI: 10.1016/j.foodchem.2017.11.113] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 11/24/2017] [Accepted: 11/29/2017] [Indexed: 11/27/2022]
Abstract
This work was designed as a proof of concept, to demonstrate the successful use of the comparison between theoretical and experimental collision cross section (CCS) values to support the identification of isomeric forms. To this purpose, thirteen mycotoxins were considered and analyzed using drift time ion mobility mass spectrometry. A good linear correlation (r2 = 0.962) between theoretical and experimental CCS was found. The average ΔCCS was 3.2%, fully consistent with the acceptability threshold value commonly set at 5%. The agreement between theoretical and experimental CCS obtained for mycotoxin glucuronides suggested the potential of the CCS matching in supporting the annotation procedure.
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Affiliation(s)
- Laura Righetti
- Department of Food Analysis and Nutrition, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic; Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Marie Fenclova
- Department of Food Analysis and Nutrition, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic
| | - Luca Dellafiora
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
| | - Jana Hajslova
- Department of Food Analysis and Nutrition, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic
| | - Milena Stranska-Zachariasova
- Department of Food Analysis and Nutrition, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic.
| | - Chiara Dall'Asta
- Department of Food and Drug, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy
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20
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Stypuła-Trębas S, Minta M, Radko L, Jedziniak P, Posyniak A. Nonsteroidal mycotoxin alternariol is a full androgen agonist in the yeast reporter androgen bioassay. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2017; 55:208-211. [PMID: 28910742 DOI: 10.1016/j.etap.2017.08.036] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 08/22/2017] [Accepted: 08/24/2017] [Indexed: 06/07/2023]
Abstract
Alternariol (AOH) is a toxic metabolite of phytopathogenic fungi of the Alternaria spp. and important contaminant of agricultural commodities. According to the recent studies, AOH has a potential to modulate the endocrine system of humans and animals. In the view of these reports, our study addressed the effects of AOH on human estrogen receptor (hERα) and androgen receptor (hAR) signaling with the use of the yeast estrogen and androgen reporter bioassays. Our results show that, apart from a weak estrogenic response, AOH induces full androgenic response of the bioassay with the EC50 of 269.4μM. The androgenic potency of AOH relative to testosterone (T) is 0.046%. Moreover, in the presence of T, AOH at 5μM acts as a weak antiandrogen, whereas at higher concentrations AOH sum up with the androgenic activity of T in a dose-dependent manner, suggesting additive effect. To our knowledge it is the first report of the androgenic potency of natural, nonsteroidal substance and may have the impact on the direction of the further studies. Further research is warranted to clarify the role of AOH in disruption of AR signaling in humans and animals.
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Affiliation(s)
- Sylwia Stypuła-Trębas
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100 Pulawy, Poland.
| | - Maria Minta
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100 Pulawy, Poland
| | - Lidia Radko
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100 Pulawy, Poland
| | - Piotr Jedziniak
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100 Pulawy, Poland
| | - Andrzej Posyniak
- Department of Pharmacology and Toxicology, National Veterinary Research Institute, Al. Partyzantow 57, 24-100 Pulawy, Poland
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21
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Gruber-Dorninger C, Novak B, Nagl V, Berthiller F. Emerging Mycotoxins: Beyond Traditionally Determined Food Contaminants. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:7052-7070. [PMID: 27599910 DOI: 10.1021/acs.jafc.6b03413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Modern analytical techniques can determine a multitude of fungal metabolites contaminating food and feed. In addition to known mycotoxins, for which maximum levels in food are enforced, also currently unregulated, so-called "emerging mycotoxins" were shown to occur frequently in agricultural products. The aim of this review is to critically discuss the relevance of selected emerging mycotoxins to food and feed safety. Acute and chronic toxicity as well as occurrence data are presented for enniatins, beauvericin, moniliformin, fusaproliferin, fusaric acid, culmorin, butenolide, sterigmatocystin, emodin, mycophenolic acid, alternariol, alternariol monomethyl ether, and tenuazonic acid. By far not all of the detected compounds are toxicologically relevant at their naturally occurring levels and are therefore of little or no health concern to consumers. Still, gaps in knowledge have been identified for several compounds. These gaps should be closed by the scientific community in the coming years to allow a proper risk assessment.
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Affiliation(s)
| | - Barbara Novak
- BIOMIN Research Center , Technopark 1, 3430 Tulln, Austria
| | - Veronika Nagl
- BIOMIN Research Center , Technopark 1, 3430 Tulln, Austria
| | - Franz Berthiller
- Christian Doppler Laboratory for Mycotoxin Metabolism and Center for Analytical Chemistry, Department of Agrobiotechnology (IFA-Tulln), University of Natural Resources and Life Sciences, Vienna (BOKU) , Konrad-Lorenz-Strasse 20, 3430 Tulln, Austria
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23
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Tiessen C, Ellmer D, Mikula H, Pahlke G, Warth B, Gehrke H, Zimmermann K, Heiss E, Fröhlich J, Marko D. Impact of phase I metabolism on uptake, oxidative stress and genotoxicity of the emerging mycotoxin alternariol and its monomethyl ether in esophageal cells. Arch Toxicol 2016; 91:1213-1226. [PMID: 27422292 PMCID: PMC5316404 DOI: 10.1007/s00204-016-1801-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Accepted: 07/07/2016] [Indexed: 12/14/2022]
Abstract
Studies on the genotoxicity of Alternaria mycotoxins focus primarily on the native compounds. Alternariol (AOH) and its methyl ether (AME) have been reported to represent substrates for cytochrome P450 enzymes, generating hydroxylated metabolites. The impact of these phase I metabolites on genotoxicity remains unknown. In the present study, the synthesis and the toxicological effects of the metabolites 4-hydroxy alternariol (4-OH-AOH) and 4-hydroxy alternariol monomethyl ether (4-OH-AME) are presented and compared to the effects of the parent molecules. Although the two phase I metabolites contain a catecholic structure, which is expected to be involved in redox cycling, only 4-OH-AOH increased reactive oxygen species (ROS) in human esophageal cells (KYSE510), 4 times more pronounced than AOH. No ROS induction was observed for 4-OH-AME, although the parent compound showed some minor impact. Under cell-free conditions, both metabolites inhibited topoisomerase II activity comparable to their parent compounds. In KYSE510 cells, both metabolites were found to enhance the level of transient DNA–topoisomerase complexes in the ICE assay. Although the level of ROS was significantly increased by 4-OH-AOH, neither DNA strand breaks nor enhanced levels of formamidopyrimidine-DNA-glycosylase (FPG)-sensitive sites were observed. In contrast, AOH induced significant DNA damage in KYSE510 cells. Less pronounced or even absent effects of hydroxylated metabolites compared to the parent compounds might at least partly be explained by their poor cellular uptake. Glucuronidation as well as sulfation appear to have only a minor influence. Instead, methylation of 4-OH-AOH seems to be the preferred way of metabolism in KYSE510 cells, whereby the toxicological relevance of the methylation product remains to be clarified.
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Affiliation(s)
- Christine Tiessen
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria
| | - Doris Ellmer
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, 1060, Vienna, Austria
| | - Hannes Mikula
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, 1060, Vienna, Austria
| | - Gudrun Pahlke
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria
| | - Benedikt Warth
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria
| | - Helge Gehrke
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria
| | - Kristin Zimmermann
- Department of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria
| | - Elke Heiss
- Department of Pharmacognosy, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria
| | - Johannes Fröhlich
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163, 1060, Vienna, Austria
| | - Doris Marko
- Department of Food Chemistry and Toxicology, Faculty of Chemistry, University of Vienna, Waehringer Str. 38, 1090, Vienna, Austria.
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24
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Lemke A, Burkhardt B, Bunzel D, Pfeiffer E, Metzler M, Huch M, Kulling SE, Franz C. Alternaria toxins of the alternariol type are not metabolised by human faecal microbiota. WORLD MYCOTOXIN J 2016. [DOI: 10.3920/wmj2014.1875] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The metabolism of the Alternaria toxins alternariol (AOH), alternariol-9-O-methyl ether (AME) and altenuene (ALT) by the microbiota present in faeces from three human volunteers was studied. Faecal cultures were prepared as a 5% faeces suspension in brain-heart infusion broth and incubated with 50 μM of the toxins under anaerobic conditions for 72 h at 37 °C. The metabolism of AOH was also studied in pure bacterial cultures with either Escherichia coli DH5α or Lactobacillus plantarum BFE 5092 for 72 h at 37 °C. The three parent toxins were stable in uninoculated, heat-treated medium over a 72 h incubation period with a recovery of more than 90%. As a control for the activity of the faecal microbiota, the isoflavone daidzein was incubated with the faecal cultures and was transformed to its expected metabolites. In contrast, no metabolites of AOH, AME and ALT could be detected in the faecal cultures from the same volunteers, indicating that the gut microbiota was not capable of metabolising these substances. The Alternaria toxins could be shown to be at least partially bound to bacterial cells in a non-covalent manner, which may serve as a mechanism for their removal from the gut.
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Affiliation(s)
- A. Lemke
- Max Rubner-Institut, Department of Safety and Quality of Fruit and Vegetables, Haid-und-Neu-Straβe 9, 76131 Karlsruhe, Germany
| | - B. Burkhardt
- Karlsruhe Institute of Technology (KIT), Institute for Applied Biosciences, Department of Food Science and Food Toxicology, Adenauerring 20, 76131 Karlsruhe, Germany
| | - D. Bunzel
- Max Rubner-Institut, Department of Safety and Quality of Fruit and Vegetables, Haid-und-Neu-Straβe 9, 76131 Karlsruhe, Germany
| | - E. Pfeiffer
- Karlsruhe Institute of Technology (KIT), Institute for Applied Biosciences, Department of Food Science and Food Toxicology, Adenauerring 20, 76131 Karlsruhe, Germany
| | - M. Metzler
- Karlsruhe Institute of Technology (KIT), Institute for Applied Biosciences, Department of Food Science and Food Toxicology, Adenauerring 20, 76131 Karlsruhe, Germany
| | - M. Huch
- Max Rubner-Institut, Department of Safety and Quality of Fruit and Vegetables, Haid-und-Neu-Straβe 9, 76131 Karlsruhe, Germany
| | - S. E. Kulling
- Max Rubner-Institut, Department of Safety and Quality of Fruit and Vegetables, Haid-und-Neu-Straβe 9, 76131 Karlsruhe, Germany
| | - C.M.A.P. Franz
- Max Rubner-Institut, Department of Safety and Quality of Fruit and Vegetables, Haid-und-Neu-Straβe 9, 76131 Karlsruhe, Germany
- Max Rubner-Institut, Department of Microbiology and Biotechnology, Hermann-Weigmann-Straβe 1, 24103 Kiel, Germany
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25
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Dellafiora L, Dall’Asta C, Cruciani G, Galaverna G, Cozzini P. Molecular modelling approach to evaluate poisoning of topoisomerase I by alternariol derivatives. Food Chem 2015; 189:93-101. [DOI: 10.1016/j.foodchem.2015.02.083] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Revised: 02/16/2015] [Accepted: 02/17/2015] [Indexed: 11/30/2022]
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26
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Pahlke G, Tiessen C, Domnanich K, Kahle N, Groh IAM, Schreck I, Weiss C, Marko D. Impact of Alternaria toxins on CYP1A1 expression in different human tumor cells and relevance for genotoxicity. Toxicol Lett 2015; 240:93-104. [PMID: 26474839 DOI: 10.1016/j.toxlet.2015.10.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 10/05/2015] [Accepted: 10/08/2015] [Indexed: 10/22/2022]
Abstract
The Alternaria toxins alternariol (AOH) and alternariol monomethyl ether (AME) have been reported previously to act as activators of the aryl hydrocarbon receptor (AhR) in murine hepatoma cells, thus enhancing the expression of cytochrome P450 (CYP) 1A monooxygenases. Concomitantly, both benzopyrones represent substrates of CYP1A, giving rise to catecholic metabolites. The impact of AOH and AME on CYP1A expression in human cells of different tissue origin colon (HT29), esophagus (KYSE510), liver (HepG2) and their effects on cell viability, generation of reactive oxygen species (ROS) and DNA integrity were investigated. ROS production was induced by both mycotoxins in all cell lines with AOH exhibiting the highest potency in esophageal cells concomitant with the most prominent CYP1A induction level. Of note, altertoxin-II (ATX-II), the more potent DNA-damaging mutagen formed by Alternaria alternata, induces CYP1A even at significant lower concentrations. AhR-siRNA knockdown in human esophageal cells supported the hypothesis of AhR-mediated CYP1A1 induction by AOH. However, DNA damage was minor at CYP1A1-inducing AOH concentrations. AhR-depletion did not affect the DNA-damaging properties of AOH indicating no substantial impact of AhR in this regard. However, in combination with xenobiotics prone to metabolic activation by CYP1A the induction of CYP1A by Alternaria toxins deserves further attention.
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Affiliation(s)
- G Pahlke
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, A-1090 Vienna, Austria.
| | - C Tiessen
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, A-1090 Vienna, Austria
| | - K Domnanich
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, A-1090 Vienna, Austria
| | - N Kahle
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, A-1090 Vienna, Austria
| | - I A M Groh
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, A-1090 Vienna, Austria
| | - I Schreck
- Institute of Toxicology and Genetics (ITG), Karlsruhe Institute of Technology (KIT), Germany
| | - C Weiss
- Institute of Toxicology and Genetics (ITG), Karlsruhe Institute of Technology (KIT), Germany
| | - D Marko
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, A-1090 Vienna, Austria
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27
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Hildebrand AA, Kohn BN, Pfeiffer E, Wefers D, Metzler M, Bunzel M. Conjugation of the mycotoxins alternariol and alternariol monomethyl ether in tobacco suspension cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:4728-36. [PMID: 25912034 DOI: 10.1021/acs.jafc.5b00806] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The mycotoxins alternariol (AOH) and alternariol-9-O-methyl ether (AME) carry three and two phenolic hydroxyl groups, respectively, which makes them candidates for the formation of conjugated metabolites in plants. Such conjugates may escape routine methods of analysis and have therefore been termed masked or, more recently, modified mycotoxins. We report now that AOH and AME are extensively conjugated in suspension cultures of tobacco BY-2 cells. Five conjugates of AOH were identified by MS and NMR spectroscopy as β-D-glucopyranosides (attached in AOH 3- or 9-position) as well as their 6'-malonyl derivatives, and as a gentiobiose conjugate. For AME, conjugation resulted in the d-glucopyranoside (mostly attached in the AME 3-position) and its 6'- and 4'-malonyl derivatives. Pronounced differences were noted for the quantitative pattern of AOH and AME conjugates as well as for their phytotoxicity. Our in vitro study demonstrates for the first time that masked mycotoxins of AOH and AME can be formed in plant cells.
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Affiliation(s)
- Andreas A Hildebrand
- Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
| | - Beate N Kohn
- Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
| | - Erika Pfeiffer
- Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
| | - Daniel Wefers
- Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
| | - Manfred Metzler
- Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
| | - Mirko Bunzel
- Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Karlsruhe Institute of Technology (KIT), Adenauerring 20a, 76131 Karlsruhe, Germany
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28
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Fleck SC, Pfeiffer E, Podlech J, Metzler M. Epoxide reduction to an alcohol: a novel metabolic pathway for perylene quinone-type alternaria mycotoxins in mammalian cells. Chem Res Toxicol 2014; 27:247-53. [PMID: 24428710 DOI: 10.1021/tx400366w] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The group of perylene quinone-type Alternaria toxins contains several congeners with epoxide groups, for example, altertoxin II (ATX II) and stemphyltoxin III (STTX III). Recent studies in our laboratory have disclosed that the epoxide moieties of ATX II and STTX III are reduced to alcohols in human colon Caco-2 cells, thereby resulting in the formation of altertoxin I (ATX I) and alteichin, respectively. In the present study, this pathway was demonstrated for ATX II in three other mammalian cell lines. Furthermore, the chemical reaction of this toxin with monothiols like glutathione could be shown, and the structures of the reaction products were tentatively elucidated by UV and mass spectrometry. Chemical reaction of ATX II with dithiols capable of forming five- and six-membered rings gave rise to ATX I, thus providing a clue for the molecular mechanism of the epoxide reduction pathway of ATX II. Both epoxide reduction and glutathione conjugation appear to attenuate, but not completely abolish, the genotoxicity of ATX II.
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Affiliation(s)
- Stefanie C Fleck
- Institute of Applied Biosciences, Unit of Food Toxicology, Karlsruhe Institute of Technology (KIT) , Karlsruhe D-76131, Germany
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29
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30
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Demuner AJ, Barbosa LCA, Miranda ACM, Geraldo GC, da Silva CM, Giberti S, Bertazzini M, Forlani G. The fungal phytotoxin alternariol 9-methyl ether and some of its synthetic analogues inhibit the photosynthetic electron transport chain. JOURNAL OF NATURAL PRODUCTS 2013; 76:2234-2245. [PMID: 24245962 DOI: 10.1021/np4005882] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Alternariol and monomethylalternariol are natural phytotoxins produced by some fungal strains, such as Nimbya and Alternaria. These substances confer virulence to phytopathogens, yet no information is available concerning their mode of action. Here we show that in the micromolar range alternariol 9-methyl ether is able to inhibit the electron transport chain (IC50 = 29.1 ± 6.5 μM) in isolated spinach chloroplasts. Since its effectiveness is limited by poor solubility in water, several alternariol analogues were synthesized using different aromatic aldehydes. The synthesized 6H-benzo[c]cromen-6-ones, 5H-chromene[4,3-b]pyridin-5-one, and 5H-chromene[4,3-c]pyridin-5-one also showed inhibitory properties, and three 6H-benzo[c]cromen-6-ones were more effective (IC50 = 12.8-22.8 μM) than the lead compound. Their addition to the culture medium of a cyanobacterial model strain was found to inhibit algal growth, with a relative effectiveness that was consistent with their activity in vitro. In contrast, the growth of a nonphotosynthetic plant cell culture was poorly affected. These compounds may represent a novel lead for the development of new active principles targeting photosynthesis.
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Affiliation(s)
- Antonio Jacinto Demuner
- Department of Chemistry, Federal University of Viçosa , Av. P.H. Rolfs, Viçosa, Minas Geraís, 36570-000, Brazil
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31
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Tiessen C, Gehrke H, Kropat C, Schwarz C, Bächler S, Fehr M, Pahlke G, Marko D. Role of topoisomerase inhibition and DNA repair mechanisms in the genotoxicity of alternariol and altertoxin-II. WORLD MYCOTOXIN J 2013. [DOI: 10.3920/wmj2013.1592] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Alternariol (AOH) and altertoxin-II (ALTX-II) have been demonstrated to possess genotoxic properties. However, the underlying mechanisms of action have not been fully elucidated yet. AOH has recently been shown to act as a topoisomerase I and II poison, contributing to its genotoxic properties. The topoisomerase-specific repair factor tyrosyl-DNA-phosphodiesterase-1 (TDP1) is involved in the respective repair processes of damaged DNA induced by topoisomerase II poison. In the present study, we investigated the role of DNA repair pathways for the extent of DNA damage by AOH and addressed the question whether interference with topoisomerase II might play a role in the genotoxicity of ALTX-II. Under cell-free conditions, AOH and ALTX-II suppressed the activity of topoisomerase II at a comparable concentration range. In HT29 cells, AOH enhanced the level of covalent DNA-topoisomerase II complexes, thus acting as a topoisomerase poison in DNA damaging concentrations. In contrast, ALTX-II in genotoxic concentrations did not show any effect on the stability of these complexes, indicating that interference with topoisomerases does not play a relevant role in genotoxicity. The differences in genotoxic mechanisms seem to be reflected in the activation of p53. AOH was found to increase p53 phosphorylation in HT29 cells in DNA damaging concentrations. In contrast, incubation with ALTX-II did not affect p53 phosphorylation despite substantial increase in tail intensity in the comet assay, suggesting that the DNA lesions formed by ALTX-II are not detected by the DNA-repair machinery of HT29 cells. These results are supported by differences in persistence of DNA damage, still maintained after 24 h for ALTX-II but nearly vanished already after 3 h for AOH. Furthermore, microarray and qPCR analysis did not indicate any substantial impact of AOH on the transcription of key elements of DNA repair pathways. However, siRNA-approaches indicate that, in addition to TDP1, the expression of other elements of the DNA repair machinery exemplified by the 70 kDa Ku autoantigen and the proliferating cell nuclear antigen are relevant for AOH-mediated DNA damage.
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Affiliation(s)
- C. Tiessen
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - H. Gehrke
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - C. Kropat
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - C. Schwarz
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - S. Bächler
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - M. Fehr
- Institute of Applied Biosciences, Section of Food Toxicology, Karlsruher Institut für Technologie, Adenauerring 20, 76131 Karlsruhe, Germany
| | - G. Pahlke
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
| | - D. Marko
- Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38, 1090 Vienna, Austria
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32
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Frizzell C, Ndossi D, Kalayou S, Eriksen GS, Verhaegen S, Sørlie M, Elliott CT, Ropstad E, Connolly L. An in vitro investigation of endocrine disrupting effects of the mycotoxin alternariol. Toxicol Appl Pharmacol 2013; 271:64-71. [PMID: 23665424 DOI: 10.1016/j.taap.2013.05.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 04/26/2013] [Accepted: 05/02/2013] [Indexed: 11/18/2022]
Abstract
Alternariol (AOH) is a mycotoxin commonly produced by Alternaria alternata on a wide range of foods. Few studies to date have been performed to evaluate the effects of AOH on endocrine activity. The present study makes use of in vitro mammalian cellular based assays and gene expression to investigate the ability of AOH to act as an endocrine disruptor by various modes of action. Reporter gene assays (RGAs), incorporating natural steroid hormone receptors for oestrogens, androgens, progestagens and glucocorticoids were used to identify endocrine disruption at the level of nuclear receptor transcriptional activity, and the H295R steroidogenesis assay was used to assess endocrine disruption at the level of gene expression and steroid hormone production. AOH exhibited a weak oestrogenic response when tested in the oestrogen responsive RGA and binding of progesterone to the progestagen receptor was shown to be synergistically increased in the presence of AOH. H295R cells when exposed to 0.1-1000ng/ml AOH, did not cause a significant change in testosterone and cortisol hormones but exposure to 1000ng/ml (3.87μM) AOH resulted in a significant increase in estradiol and progesterone production. In the gene expression study following exposure to 1000ng/ml (3.87μM) AOH, only one gene NR0B1 was down-regulated, whereas expression of mRNA for CYP1A1, MC2R, HSD3B2, CYP17, CYP21, CYP11B2 and CYP19 was up-regulated. Expression of the other genes investigated did not change significantly. In conclusion AOH is a weak oestrogenic mycotoxin that also has the ability to interfere with the steroidogenesis pathway.
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MESH Headings
- Androgens/metabolism
- Cell Line, Tumor
- Dose-Response Relationship, Drug
- Down-Regulation/drug effects
- Endocrine Disruptors/administration & dosage
- Endocrine Disruptors/toxicity
- Estrogens/metabolism
- Genes, Reporter
- Glucocorticoids/metabolism
- Humans
- Lactones/administration & dosage
- Lactones/toxicity
- Progestins/metabolism
- RNA, Messenger/metabolism
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Receptors, Estrogen/genetics
- Receptors, Estrogen/metabolism
- Receptors, Glucocorticoid/genetics
- Receptors, Glucocorticoid/metabolism
- Receptors, Progesterone/genetics
- Receptors, Progesterone/metabolism
- Up-Regulation/drug effects
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Affiliation(s)
- Caroline Frizzell
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Northern Ireland, UK
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33
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Mikula H, Weber J, Lexmüller S, Bichl G, Schwartz H, Varga E, Berthiller F, Hametner C, Krska R, Fröhlich J. Simultaneous preparation of α/β-zearalenol glucosides and glucuronides. Carbohydr Res 2013; 373:59-63. [DOI: 10.1016/j.carres.2013.03.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 02/28/2013] [Accepted: 03/06/2013] [Indexed: 11/16/2022]
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34
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Tiessen C, Fehr M, Schwarz C, Baechler S, Domnanich K, Böttler U, Pahlke G, Marko D. Modulation of the cellular redox status by the Alternaria toxins alternariol and alternariol monomethyl ether. Toxicol Lett 2012; 216:23-30. [PMID: 23154127 DOI: 10.1016/j.toxlet.2012.11.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/02/2012] [Accepted: 11/03/2012] [Indexed: 12/30/2022]
Abstract
The mycotoxin alternariol (AOH) has been reported to possess genotoxic properties, inducing enhanced levels of DNA damage after only 1 h of incubation. In the present study we addressed the question whether the induction of oxidative stress might contribute to the genotoxic effects of AOH or its naturally occurring monomethylether (AME). In the dichlorofluorescein (DCF) assay, treatment of HT29 cells for 1 h enhanced the formation of dichlorofluorescein, indicative for ROS formation. The total glutathione (tGSH) was transiently decreased. In accordance with the results of the DCF assay, AOH and AME enhanced the proportion of the transcription factor Nrf2 in the nucleus. Concomitantly, the Nrf2/ARE-dependent genes γ-glutamylcysteine ligase (γ-GCL) and glutathione-S-transferase (GSTA1/2) showed enhanced transcript levels. After 24 h of incubation this effect was also reflected on the protein level by an increase of GST activity. However, in spite of the positive DCF assay and the activation of the redox-sensitive Nrf2/ARE-pathway, the level of oxidative DNA damage, measured in the comet assay by the addition of formamidopyrimidine-DNA-glycosylase (fpg) remained unaffected. Of note, after 3 h of incubation no significant DNA damaging potential of AOH and AME was detectable, indicating either inactivation of the compounds or enhanced DNA repair. In summary, the mycotoxins AOH and AME were found to modulate the redox balance of HT29 cells but without apparent negative effect on DNA integrity.
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Affiliation(s)
- Christine Tiessen
- University of Vienna, Department of Food Chemistry and Toxicology, Waehringer Str. 38, A-1090 Vienna, Austria
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35
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Burkhardt B, Jung SA, Pfeiffer E, Weiss C, Metzler M. Mouse hepatoma cell lines differing in aryl hydrocarbon receptor-mediated signaling have different activities for glucuronidation. Arch Toxicol 2011; 86:643-9. [DOI: 10.1007/s00204-011-0789-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Accepted: 11/21/2011] [Indexed: 01/19/2023]
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36
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Scientific Opinion on the risks for animal and public health related to the presence ofAlternariatoxins in feed and food. EFSA J 2011. [DOI: 10.2903/j.efsa.2011.2407] [Citation(s) in RCA: 301] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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37
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Schebb NH, Franze B, Maul R, Ranganathan A, Hammock BD. In vitro glucuronidation of the antibacterial triclocarban and its oxidative metabolites. Drug Metab Dispos 2011; 40:25-31. [PMID: 21953915 DOI: 10.1124/dmd.111.042283] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Triclocarban (3,4,4'-trichlorocarbanilide; TCC) is widely used as an antibacterial in bar soaps. During use of these soaps, a significant portion of TCC is absorbed by humans. For the elimination from the body, glucuronidation plays a key role in both biliary and renal clearance. To investigate this metabolic pathway, we performed microsomal incubations of TCC and its hydroxylated metabolites 2'-OH-TCC, 3'-OH-TCC, and 6-OH-TCC. Using a new liquid chromatography-UV-mass spectrometry method, we could show a rapid glucuronidation for all OH-TCCs by the uridine-5'-diphosphate-glucuronosyltransferases (UGT) present in liver microsomes of humans (HLM), cynomolgus monkeys (CLM), rats (RLM), and mice (MLM). Among the tested human UGT isoforms, UGT1A7, UGT1A8, and UGT1A9 showed the highest activity for the conjugation of hydroxylated TCC metabolites followed by UGT1A1, UGT1A3, and UGT1A10. Due to this broad pattern of active UGTs, OH-TCCs can be efficiently glucuronidated in various tissues, as shown for microsomes from human kidney (HKM) and intestine (HIM). The major renal metabolites in humans, TCC-N-glucuronide and TCC-N'-glucuronide, were formed at very low conversion rates (<1%) by microsomal incubations. Low amounts of N-glucuronides were generated by HLM, HIM, and HKM, as well as by MLM and CLM, but not by RLM, according to the observed species specificity of this metabolic pathway. Among the human UGT isoforms, only UGT1A9 had activity for the N-glucuronidation of TCC. These results present an anomaly where in vivo the predominant urinary metabolites of TCC are N and N'-glucuronides, but these compounds are slowly produced in vitro.
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Affiliation(s)
- N H Schebb
- University of Veterinary Medicine Hannover, Institute for Food Toxicology and Chemical Analysis, Hannover, Germany
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Ackermann Y, Curtui V, Dietrich R, Gross M, Latif H, Märtlbauer E, Usleber E. Widespread occurrence of low levels of alternariol in apple and tomato products, as determined by comparative immunochemical assessment using monoclonal and polyclonal antibodies. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:6360-6368. [PMID: 21534631 DOI: 10.1021/jf201516f] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This study investigated the production of polyclonal (pAB) antibodies and the first time production of monoclonal (mAB) antibodies against the mycotoxin alternariol, and their implementation in enzyme immunoassay (EIA) for the rapid determination of alternariol in foods. Both EIAs were highly sensitive, with detection limits (IC₂₀) of 35 ± 6.9 pg/mL (mAb EIA) and 59 ± 16 pg/mL (pAb EIA). Food products (n = 109; apple and tomato products, white wine) from German retail shops were analyzed. At a detection limit of 1-2 μg/kg, alternariol at 1-13 μg/kg was found with high frequency in apple (67%) and tomato (93%) products. Tomatoes with visible signs of Alternaria infection, stored at room temperature for up to 4 weeks, contained alternariol at levels up to 50 mg/kg, as determined by EIA and HPLC-FLD. It is concluded that the alternariol immunoassays present a versatile screening tool which could facilitate food control for Alternaria toxins.
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Affiliation(s)
- Yvonne Ackermann
- Chair of Dairy Science, Institute of Veterinary Food Science, Veterinary Faculty, Justus Liebig-University, Ludwigstrasse 21, 35390 Giessen, Germany.
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Burkhardt B, Wittenauer J, Pfeiffer E, Schauer UMD, Metzler M. Oxidative metabolism of the mycotoxins alternariol and alternariol-9-methyl ether in precision-cut rat liver slices in vitro. Mol Nutr Food Res 2011; 55:1079-86. [DOI: 10.1002/mnfr.201000487] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 01/10/2011] [Accepted: 01/11/2011] [Indexed: 12/25/2022]
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Pfeiffer E, Hildebrand A, Mikula H, Metzler M. Glucuronidation of zearalenone, zeranol and four metabolites in vitro: Formation of glucuronides by various microsomes and human UDP-glucuronosyltransferase isoforms. Mol Nutr Food Res 2010; 54:1468-76. [DOI: 10.1002/mnfr.200900524] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Shephard G, Berthiller F, Dorner J, Krska R, Lombaert G, Malone B, Maragos C, Sabino M, Solfrizzo M, Trucksess M, van Egmond H, Whitaker T. Developments in mycotoxin analysis: an update for 2008-2009. WORLD MYCOTOXIN J 2010. [DOI: 10.3920/wmj2009.1172] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This review highlights developments in mycotoxin analysis and sampling over a period between mid-2008 and mid-2009. It covers the major mycotoxins: aflatoxins, alternaria toxins, cyclopiazonic acid, fumonisins, ochratoxin, patulin, trichothecenes and zearalenone. Developments in mycotoxin analysis continue, with emphasis on novel immunological methods and further description of LC-MS and LC-MS/MS, particularly as multimycotoxin applications for different ranges of mycotoxins. Although falling outside the main emphasis of the review, some aspects of natural occurrence have been mentioned, especially if linked to novel method developments.
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Affiliation(s)
- G. Shephard
- PROMEC Unit, Medical Research Council, P.O. Box 19070, Tygerberg 7505, South Africa
| | - F. Berthiller
- Department for Agrobiotechnology (IFA-Tulln), Christian Doppler Laboratory for Mycotoxin Research, University of Natural Resources and Applied Life Sciences Vienna, Center for Analytical Chemistry, Konrad Lorenz Str. 20, 3430 Tulln, Austria
| | - J. Dorner
- USDA, ARS, National Peanut Research Laboratory, P.O. Box 509, 1011 Forrester Dr SE, Dawson, GA 31742, USA
| | - R. Krska
- Department for Agrobiotechnology (IFA-Tulln), Christian Doppler Laboratory for Mycotoxin Research, University of Natural Resources and Applied Life Sciences Vienna, Center for Analytical Chemistry, Konrad Lorenz Str. 20, 3430 Tulln, Austria
| | - G. Lombaert
- Health Canada, 510 Lagimodiere Blvd., Winnipeg, MB, R2J 3Y1, Canada
| | - B. Malone
- Trilogy Analytical Laboratory, 111 West Fourth Street, Washington, MO 63090, USA
| | - C. Maragos
- USDA, ARS National Center for Agricultural Utilization Research, 1815 N. University St, Peoria, IL 61604, USA
| | - M. Sabino
- Instituto Adolfo Lutz, Av Dr Arnaldo 355, 01246-902, São Paulo/SP, Brazil
| | - M. Solfrizzo
- Institute of Sciences of Food Production, National Research Council, Via Amendola 122/o, Bari 700126, Italy
| | - M. Trucksess
- US Food and Drug Administration, 5100 Paint Branch Parkway, College Park, MD 20740, USA
| | - H. van Egmond
- RIKILT, Cluster Natural Toxins & Pesticides, P.O. Box 230, 6700 AE Wageningen, the Netherlands
| | - T. Whitaker
- Biological and Agricultural Engineering Department, P.O. Box 7625, N.C. State University, Raleigh, NC 27695-7625 USA
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Burkhardt B, Pfeiffer E, Metzler M. Absorption and metabolism of the mycotoxins alternariol and alternariol-9-methyl ether in Caco-2 cells in vitro. Mycotoxin Res 2009; 25:149-57. [DOI: 10.1007/s12550-009-0022-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 08/17/2009] [Accepted: 08/19/2009] [Indexed: 11/25/2022]
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