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Schrenk D, Bignami M, Bodin L, Chipman JK, del Mazo J, Grasl‐Kraupp B, Hogstrand C, (Ron) Hoogenboom L, Leblanc J, Nebbia CS, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T, Wallace H, Benford D, Fürst P, Hart A, Rose M, Schroeder H, Vrijheid M, Ioannidou S, Nikolič M, Bordajandi LR, Vleminckx C. Update of the risk assessment of polybrominated diphenyl ethers (PBDEs) in food. EFSA J 2024; 22:e8497. [PMID: 38269035 PMCID: PMC10807361 DOI: 10.2903/j.efsa.2024.8497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024] Open
Abstract
The European Commission asked EFSA to update its 2011 risk assessment on polybrominated diphenyl ethers (PBDEs) in food, focusing on 10 congeners: BDE-28, -47, -49, -99, -100, -138, -153, -154, -183 and ‑209. The CONTAM Panel concluded that the neurodevelopmental effects on behaviour and reproductive/developmental effects are the critical effects in rodent studies. For four congeners (BDE-47, -99, -153, -209) the Panel derived Reference Points, i.e. benchmark doses and corresponding lower 95% confidence limits (BMDLs), for endpoint-specific benchmark responses. Since repeated exposure to PBDEs results in accumulation of these chemicals in the body, the Panel estimated the body burden at the BMDL in rodents, and the chronic intake that would lead to the same body burden in humans. For the remaining six congeners no studies were available to identify Reference Points. The Panel concluded that there is scientific basis for inclusion of all 10 congeners in a common assessment group and performed a combined risk assessment. The Panel concluded that the combined margin of exposure (MOET) approach was the most appropriate risk metric and applied a tiered approach to the risk characterisation. Over 84,000 analytical results for the 10 congeners in food were used to estimate the exposure across dietary surveys and age groups of the European population. The most important contributors to the chronic dietary Lower Bound exposure to PBDEs were meat and meat products and fish and seafood. Taking into account the uncertainties affecting the assessment, the Panel concluded that it is likely that current dietary exposure to PBDEs in the European population raises a health concern.
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Suciu I, Delp J, Gutbier S, Suess J, Henschke L, Celardo I, Mayer TU, Amelio I, Leist M. Definition of the Neurotoxicity-Associated Metabolic Signature Triggered by Berberine and Other Respiratory Chain Inhibitors. Antioxidants (Basel) 2023; 13:49. [PMID: 38247474 PMCID: PMC10812665 DOI: 10.3390/antiox13010049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 12/06/2023] [Accepted: 12/19/2023] [Indexed: 01/23/2024] Open
Abstract
To characterize the hits from a phenotypic neurotoxicity screen, we obtained transcriptomics data for valinomycin, diethylstilbestrol, colchicine, rotenone, 1-methyl-4-phenylpyridinium (MPP), carbaryl and berberine (Ber). For all compounds, the concentration triggering neurite degeneration correlated with the onset of gene expression changes. The mechanistically diverse toxicants caused similar patterns of gene regulation: the responses were dominated by cell de-differentiation and a triggering of canonical stress response pathways driven by ATF4 and NRF2. To obtain more detailed and specific information on the modes-of-action, the effects on energy metabolism (respiration and glycolysis) were measured. Ber, rotenone and MPP inhibited the mitochondrial respiratory chain and they shared complex I as the target. This group of toxicants was further evaluated by metabolomics under experimental conditions that did not deplete ATP. Ber (204 changed metabolites) showed similar effects as MPP and rotenone. The overall metabolic situation was characterized by oxidative stress, an over-abundance of NADH (>1000% increase) and a re-routing of metabolism in order to dispose of the nitrogen resulting from increased amino acid turnover. This unique overall pattern led to the accumulation of metabolites known as biomarkers of neurodegeneration (saccharopine, aminoadipate and branched-chain ketoacids). These findings suggest that neurotoxicity of mitochondrial inhibitors may result from an ensemble of metabolic changes rather than from a simple ATP depletion. The combi-omics approach used here provided richer and more specific MoA data than the more common transcriptomics analysis alone. As Ber, a human drug and food supplement, mimicked closely the mode-of-action of known neurotoxicants, its potential hazard requires further investigation.
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Affiliation(s)
- Ilinca Suciu
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, 78464 Konstanz, Germany
- Graduate School of Chemical Biology, University of Konstanz, 78464 Konstanz, Germany
| | - Johannes Delp
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, 78464 Konstanz, Germany
| | - Simon Gutbier
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, 78464 Konstanz, Germany
| | - Julian Suess
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, 78464 Konstanz, Germany
| | - Lars Henschke
- Graduate School of Chemical Biology, University of Konstanz, 78464 Konstanz, Germany
- Department of Molecular Genetics, University of Konstanz, 78464 Konstanz, Germany
| | - Ivana Celardo
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, 78464 Konstanz, Germany
| | - Thomas U. Mayer
- Department of Molecular Genetics, University of Konstanz, 78464 Konstanz, Germany
| | - Ivano Amelio
- Division for Systems Toxicology, Department of Biology, University of Konstanz, 78464 Konstanz, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, 78464 Konstanz, Germany
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3
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Jennings P, Carta G, Singh P, da Costa Pereira D, Feher A, Dinnyes A, Exner TE, Wilmes A. Capturing time-dependent activation of genes and stress-response pathways using transcriptomics in iPSC-derived renal proximal tubule cells. Cell Biol Toxicol 2023; 39:1773-1793. [PMID: 36586010 PMCID: PMC10425493 DOI: 10.1007/s10565-022-09783-5] [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: 07/11/2022] [Accepted: 12/06/2022] [Indexed: 01/01/2023]
Abstract
Transcriptomic analysis is a powerful method in the utilization of New Approach Methods (NAMs) for identifying mechanisms of toxicity and application to hazard characterization. With this regard, mapping toxicological events to time of exposure would be helpful to characterize early events. Here, we investigated time-dependent changes in gene expression levels in iPSC-derived renal proximal tubular-like cells (PTL) treated with five diverse compounds using TempO-Seq transcriptomics with the aims to evaluate the application of PTL for toxicity prediction and to report on temporal effects for the activation of cellular stress response pathways. PTL were treated with either 50 μM amiodarone, 10 μM sodium arsenate, 5 nM rotenone, or 300 nM tunicamycin over a temporal time course between 1 and 24 h. The TGFβ-type I receptor kinase inhibitor GW788388 (1 μM) was used as a negative control. Pathway analysis revealed the induction of key stress-response pathways, including Nrf2 oxidative stress response, unfolding protein response, and metal stress response. Early response genes per pathway were identified much earlier than 24 h and included HMOX1, ATF3, DDIT3, and several MT1 isotypes. GW788388 did not induce any genes within the stress response pathways above, but showed deregulation of genes involved in TGFβ inhibition, including downregulation of CYP24A1 and SERPINE1 and upregulation of WT1. This study highlights the application of iPSC-derived renal cells for prediction of cellular toxicity and sheds new light on the temporal and early effects of key genes that are involved in cellular stress response pathways.
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Affiliation(s)
- Paul Jennings
- Division of Molecular and Computational Toxicology, Chemistry and Pharmaceutical Sciences, AIMMS, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Giada Carta
- Division of Molecular and Computational Toxicology, Chemistry and Pharmaceutical Sciences, AIMMS, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Pranika Singh
- Edelweiss Connect GmbH, Technology Park Basel, Hochbergerstrasse 60C, 4057, Basel, Switzerland
- Division of Molecular and Systems Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstrasse 50, 4056, Basel, Switzerland
| | - Daniel da Costa Pereira
- Division of Molecular and Computational Toxicology, Chemistry and Pharmaceutical Sciences, AIMMS, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Anita Feher
- BioTalentum Ltd, Aulich Lajos Street 26, Gödöllő, 2100, Hungary
| | - Andras Dinnyes
- BioTalentum Ltd, Aulich Lajos Street 26, Gödöllő, 2100, Hungary
- HCEMM-USZ Stem Cell Research Group, Hungarian Centre of Excellence for Molecular Medicine, Szeged, 6723, Hungary
| | - Thomas E Exner
- Seven Past Nine d.o.o., Hribljane 10, 1380, Cerknica, Slovenia
| | - Anja Wilmes
- Division of Molecular and Computational Toxicology, Chemistry and Pharmaceutical Sciences, AIMMS, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
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BDE-47 Induces Immunotoxicity in RAW264.7 Macrophages through the Reactive Oxygen Species-Mediated Mitochondrial Apoptotic Pathway. Molecules 2023; 28:molecules28052036. [PMID: 36903282 PMCID: PMC10004313 DOI: 10.3390/molecules28052036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 02/17/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Polybrominated diphenyl ethers (PBDEs) are classic and emerging pollutants that are potentially harmful to the human immune system. Research on their immunotoxicity and mechanisms suggests that they play an important role in the resulting pernicious effects of PBDEs. 2,2',4,4'-Tetrabrominated biphenyl ether (BDE-47) is the most biotoxic PBDE congener, and, in this study, we evaluated its toxicity toward RAW264.7 cells of mouse macrophages. The results show that exposure to BDE-47 led to a significant decrease in cell viability and a prominent increase in apoptosis. A decrease in mitochondrial membrane potential (MMP) and an increase in cytochrome C release and caspase cascade activation thus demonstrate that cell apoptosis induced by BDE-47 occurs via the mitochondrial pathway. In addition, BDE-47 inhibits phagocytosis in RAW264.7 cells, changes the related immune factor index, and causes immune function damage. Furthermore, we discovered a significant increase in the level of cellular reactive oxygen species (ROS), and the regulation of genes linked to oxidative stress was also demonstrated using transcriptome sequencing. The degree of apoptosis and immune function impairment caused by BDE-47 could be reversed after treatment with the antioxidant NAC and, conversely, exacerbated by treatment with the ROS-inducer BSO. These findings indicate that oxidative damage caused by BDE-47 is a critical event that leads to mitochondrial apoptosis in RAW264.7 macrophages, ultimately resulting in the suppression of immune function.
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5
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Blum J, Masjosthusmann S, Bartmann K, Bendt F, Dolde X, Dönmez A, Förster N, Holzer AK, Hübenthal U, Keßel HE, Kilic S, Klose J, Pahl M, Stürzl LC, Mangas I, Terron A, Crofton KM, Scholze M, Mosig A, Leist M, Fritsche E. Establishment of a human cell-based in vitro battery to assess developmental neurotoxicity hazard of chemicals. CHEMOSPHERE 2023; 311:137035. [PMID: 36328314 DOI: 10.1016/j.chemosphere.2022.137035] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 10/20/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Developmental neurotoxicity (DNT) is a major safety concern for all chemicals of the human exposome. However, DNT data from animal studies are available for only a small percentage of manufactured compounds. Test methods with a higher throughput than current regulatory guideline methods, and with improved human relevance are urgently needed. We therefore explored the feasibility of DNT hazard assessment based on new approach methods (NAMs). An in vitro battery (IVB) was assembled from ten individual NAMs that had been developed during the past years to probe effects of chemicals on various fundamental neurodevelopmental processes. All assays used human neural cells at different developmental stages. This allowed us to assess disturbances of: (i) proliferation of neural progenitor cells (NPC); (ii) migration of neural crest cells, radial glia cells, neurons and oligodendrocytes; (iii) differentiation of NPC into neurons and oligodendrocytes; and (iv) neurite outgrowth of peripheral and central neurons. In parallel, cytotoxicity measures were obtained. The feasibility of concentration-dependent screening and of a reliable biostatistical processing of the complex multi-dimensional data was explored with a set of 120 test compounds, containing subsets of pre-defined positive and negative DNT compounds. The battery provided alerts (hit or borderline) for 24 of 28 known toxicants (82% sensitivity), and for none of the 17 negative controls. Based on the results from this screen project, strategies were developed on how IVB data may be used in the context of risk assessment scenarios employing integrated approaches for testing and assessment (IATA).
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Affiliation(s)
- Jonathan Blum
- In Vitro Toxicology and Biomedicine, Dept Inaugurated By the Doerenkamp-Zbinden Foundation, University of Konstanz, 78457, Konstanz, Germany.
| | - Stefan Masjosthusmann
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Kristina Bartmann
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Farina Bendt
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Xenia Dolde
- In Vitro Toxicology and Biomedicine, Dept Inaugurated By the Doerenkamp-Zbinden Foundation, University of Konstanz, 78457, Konstanz, Germany
| | - Arif Dönmez
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Nils Förster
- Bioinformatics Group, Ruhr University Bochum, 44801, Bochum, Germany
| | - Anna-Katharina Holzer
- In Vitro Toxicology and Biomedicine, Dept Inaugurated By the Doerenkamp-Zbinden Foundation, University of Konstanz, 78457, Konstanz, Germany
| | - Ulrike Hübenthal
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Hagen Eike Keßel
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Sadiye Kilic
- In Vitro Toxicology and Biomedicine, Dept Inaugurated By the Doerenkamp-Zbinden Foundation, University of Konstanz, 78457, Konstanz, Germany
| | - Jördis Klose
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Melanie Pahl
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Lynn-Christin Stürzl
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany
| | - Iris Mangas
- European Food Safety Authority, PREV Unit, 43126, Parma, Italy
| | - Andrea Terron
- European Food Safety Authority, PREV Unit, 43126, Parma, Italy
| | | | - Martin Scholze
- Institute of Environment Health and Societies, Brunel University London, UK
| | - Axel Mosig
- Bioinformatics Group, Ruhr University Bochum, 44801, Bochum, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Dept Inaugurated By the Doerenkamp-Zbinden Foundation, University of Konstanz, 78457, Konstanz, Germany.
| | - Ellen Fritsche
- IUF - Leibniz Research Institute for Environmental Medicine, 40225, Düsseldorf, Germany; Medical Faculty, Heinrich-Heine-University, 40225, Düsseldorf, Germany.
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Seidel F, Cherianidou A, Kappenberg F, Marta M, Dreser N, Blum J, Waldmann T, Blüthgen N, Meisig J, Madjar K, Henry M, Rotshteyn T, Scholtz-Illigens A, Marchan R, Edlund K, Leist M, Rahnenführer J, Sachinidis A, Hengstler JG. High Accuracy Classification of Developmental Toxicants by In Vitro Tests of Human Neuroepithelial and Cardiomyoblast Differentiation. Cells 2022; 11:3404. [PMID: 36359802 PMCID: PMC9653768 DOI: 10.3390/cells11213404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/20/2022] [Accepted: 10/24/2022] [Indexed: 11/29/2022] Open
Abstract
Human-relevant tests to predict developmental toxicity are urgently needed. A currently intensively studied approach makes use of differentiating human stem cells to measure chemically-induced deviations of the normal developmental program, as in a recent study based on cardiac differentiation (UKK2). Here, we (i) tested the performance of an assay modeling neuroepithelial differentiation (UKN1), and (ii) explored the benefit of combining assays (UKN1 and UKK2) that model different germ layers. Substance-induced cytotoxicity and genome-wide expression profiles of 23 teratogens and 16 non-teratogens at human-relevant concentrations were generated and used for statistical classification, resulting in accuracies of the UKN1 assay of 87-90%. A comparison to the UKK2 assay (accuracies of 90-92%) showed, in general, a high congruence in compound classification that may be explained by the fact that there was a high overlap of signaling pathways. Finally, the combination of both assays improved the prediction compared to each test alone, and reached accuracies of 92-95%. Although some compounds were misclassified by the individual tests, we conclude that UKN1 and UKK2 can be used for a reliable detection of teratogens in vitro, and that a combined analysis of tests that differentiate hiPSCs into different germ layers and cell types can even further improve the prediction of developmental toxicants.
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Affiliation(s)
- Florian Seidel
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Ardeystrasse 67, 44139 Dortmund, Germany
| | - Anna Cherianidou
- Working Group Sachinidis, Center for Physiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
| | - Franziska Kappenberg
- Department of Statistics, TU Dortmund University, Vogelpothsweg 87, 44227 Dortmund, Germany
| | - Miriam Marta
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Ardeystrasse 67, 44139 Dortmund, Germany
| | - Nadine Dreser
- In Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, 78454 Konstanz, Germany
| | - Jonathan Blum
- In Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, 78454 Konstanz, Germany
| | - Tanja Waldmann
- Department of Advanced Cell Systems, trenzyme GmbH, Byk-Gulden-Str. 2, 78467 Konstanz, Germany
| | - Nils Blüthgen
- Institute of Pathology, Charité-Universitätsmedizin Berlin, Chariteplatz 1, 10117 Berlin, Germany
- IRI Life Sciences, Humboldt Universität zu Berlin, Philippstraße 13, Haus 18, 10115 Berlin, Germany
| | - Johannes Meisig
- Institute of Pathology, Charité-Universitätsmedizin Berlin, Chariteplatz 1, 10117 Berlin, Germany
- IRI Life Sciences, Humboldt Universität zu Berlin, Philippstraße 13, Haus 18, 10115 Berlin, Germany
| | - Katrin Madjar
- Department of Statistics, TU Dortmund University, Vogelpothsweg 87, 44227 Dortmund, Germany
| | - Margit Henry
- Working Group Sachinidis, Center for Physiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Tamara Rotshteyn
- Working Group Sachinidis, Center for Physiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Andreas Scholtz-Illigens
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Ardeystrasse 67, 44139 Dortmund, Germany
| | - Rosemarie Marchan
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Ardeystrasse 67, 44139 Dortmund, Germany
| | - Karolina Edlund
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Ardeystrasse 67, 44139 Dortmund, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, 78454 Konstanz, Germany
| | - Jörg Rahnenführer
- Department of Statistics, TU Dortmund University, Vogelpothsweg 87, 44227 Dortmund, Germany
| | - Agapios Sachinidis
- Working Group Sachinidis, Center for Physiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Robert-Koch-Str. 39, 50931 Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931 Cologne, Germany
| | - Jan Georg Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund, Ardeystrasse 67, 44139 Dortmund, Germany
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7
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Kowalski TW, Lord VO, Sgarioni E, Gomes JDA, Mariath LM, Recamonde-Mendoza M, Vianna FSL. Transcriptome meta-analysis of valproic acid exposure in human embryonic stem cells. Eur Neuropsychopharmacol 2022; 60:76-88. [PMID: 35635998 DOI: 10.1016/j.euroneuro.2022.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 04/02/2022] [Accepted: 04/11/2022] [Indexed: 11/04/2022]
Abstract
Valproic acid (VPA) is a widely used antiepileptic drug not recommended in pregnancy because it is teratogenic. Many assays have assessed the impact of the VPA exposure on the transcriptome of human embryonic stem-cells (hESC), but the molecular perturbations that VPA exerts in neurodevelopment are not completely understood. This study aimed to perform a transcriptome meta-analysis of VPA-exposed hESC to elucidate the main biological mechanisms altered by VPA effects on the gene expression. Publicly available microarray and RNA-seq transcriptomes were selected in the Gene Expression Omnibus (GEO) repository. Samples were processed according to the standard pipelines for each technology in the Galaxy server and R. Meta-analysis was performed using the Fisher-P method. Overrepresented genes were obtained by evaluating ontologies, pathways, and phenotypes' databases. The meta-analysis performed in seven datasets resulted in 61 perturbed genes, 54 upregulated. Ontology and pathway enrichments suggested neurodevelopment and neuroinflammatory effects; phenotype overrepresentation included epilepsy-related genes, such as SCN1A and GABRB2. The NDNF gene upregulation was also identified; this gene is involved in neuron migration and survival during development. Sub-network analysis proposed TGFβ and BMP pathways activation. These results suggest VPA exerts effects in epilepsy-related genes even in embryonic cells. Neurodevelopmental genes, such as NDNF were upregulated and VPA might also disturb several development pathways. These mechanisms might help to explain the spectrum of VPA-induced congenital anomalies and the molecular effects on neurodevelopment.
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Affiliation(s)
- Thayne Woycinck Kowalski
- Post-Graduation Program in Genetics and Molecular Biology, Genetics Department, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil; Laboratory of Genomic Medicine, Center of Experimental Research, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; National Institute of Medical Population Genetics (INAGEMP), Porto Alegre, Brazil; Bioinformatics Core, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; Centro Universitário CESUCA, Cachoeirinha, Brazil.
| | - Vinícius Oliveira Lord
- Laboratory of Genomic Medicine, Center of Experimental Research, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; Centro Universitário CESUCA, Cachoeirinha, Brazil
| | - Eduarda Sgarioni
- Laboratory of Genomic Medicine, Center of Experimental Research, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil
| | - Julia do Amaral Gomes
- Post-Graduation Program in Genetics and Molecular Biology, Genetics Department, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil; Laboratory of Genomic Medicine, Center of Experimental Research, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; National Institute of Medical Population Genetics (INAGEMP), Porto Alegre, Brazil
| | - Luiza Monteavaro Mariath
- Post-Graduation Program in Genetics and Molecular Biology, Genetics Department, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Mariana Recamonde-Mendoza
- Bioinformatics Core, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; Institute of Informatics, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Fernanda Sales Luiz Vianna
- Post-Graduation Program in Genetics and Molecular Biology, Genetics Department, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil; Laboratory of Genomic Medicine, Center of Experimental Research, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil; National Institute of Medical Population Genetics (INAGEMP), Porto Alegre, Brazil.
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8
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Cherianidou A, Seidel F, Kappenberg F, Dreser N, Blum J, Waldmann T, Blüthgen N, Meisig J, Madjar K, Henry M, Rotshteyn T, Marchan R, Edlund K, Leist M, Rahnenführer J, Sachinidis A, Hengstler JG. Classification of Developmental Toxicants in a Human iPSC Transcriptomics-Based Test. Chem Res Toxicol 2022; 35:760-773. [PMID: 35416653 PMCID: PMC9377669 DOI: 10.1021/acs.chemrestox.1c00392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Despite the progress made in developmental toxicology, there is a great need for in vitro tests that identify developmental toxicants in relation to human oral doses and blood concentrations. In the present study, we established the hiPSC-based UKK2 in vitro test and analyzed genome-wide expression profiles of 23 known teratogens and 16 non-teratogens. Compounds were analyzed at the maximal plasma concentration (Cmax) and at 20-fold Cmax for a 24 h incubation period in three independent experiments. Based on the 1000 probe sets with the highest variance and including information on cytotoxicity, penalized logistic regression with leave-one-out cross-validation was used to classify the compounds as test-positive or test-negative, reaching an area under the curve (AUC), accuracy, sensitivity, and specificity of 0.96, 0.92, 0.96, and 0.88, respectively. Omitting the cytotoxicity information reduced the test performance to an AUC of 0.94, an accuracy of 0.79, and a sensitivity of 0.74. A second method, which used the number of significantly deregulated probe sets to classify the compounds, resulted in a specificity of 1; however, the AUC (0.90), accuracy (0.90), and sensitivity (0.83) were inferior compared to those of the logistic regression-based procedure. Finally, no increased performance was achieved when the high test concentrations (20-fold Cmax) were used, in comparison to testing within the realistic clinical range (1-fold Cmax). In conclusion, although further optimization is required, for example, by including additional readouts and cell systems that model different developmental processes, the UKK2-test in its present form can support the early discovery-phase detection of human developmental toxicants.
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Affiliation(s)
- Anna Cherianidou
- Faculty
of Medicine and University Hospital Cologne, Center for Physiology,
Working Group Sachinidis, University of
Cologne, Robert-Koch-Str.
39, 50931 Cologne, Germany
| | - Florian Seidel
- Leibniz
Research Centre for Working Environment and Human Factors at the Technical
University of Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Franziska Kappenberg
- Department
of Statistics, TU Dortmund University, Vogelpothsweg 87, 44227 Dortmund, Germany
| | - Nadine Dreser
- In
Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, P.O.
Box M657, 78457 Konstanz, Germany
| | - Jonathan Blum
- In
Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, P.O.
Box M657, 78457 Konstanz, Germany
| | - Tanja Waldmann
- Department
of Advanced Cell Systems, trenzyme GmbH, Byk-Gulden-Str. 2, 78467 Konstanz, Germany
| | - Nils Blüthgen
- Institute
of Pathology, Charité-Universitätsmedizin
Berlin, Chariteplatz
1, 10117 Berlin, Germany
- IRI
Life Sciences, Humboldt Universität zu Berlin, Philippstraße 13, Haus 18, 10115 Berlin, Germany
| | - Johannes Meisig
- Institute
of Pathology, Charité-Universitätsmedizin
Berlin, Chariteplatz
1, 10117 Berlin, Germany
- IRI
Life Sciences, Humboldt Universität zu Berlin, Philippstraße 13, Haus 18, 10115 Berlin, Germany
| | - Katrin Madjar
- Department
of Statistics, TU Dortmund University, Vogelpothsweg 87, 44227 Dortmund, Germany
| | - Margit Henry
- Faculty
of Medicine and University Hospital Cologne, Center for Physiology,
Working Group Sachinidis, University of
Cologne, Robert-Koch-Str.
39, 50931 Cologne, Germany
- Center
for Molecular Medicine Cologne (CMMC), University
of Cologne, 50931 Cologne, Germany
| | - Tamara Rotshteyn
- Faculty
of Medicine and University Hospital Cologne, Center for Physiology,
Working Group Sachinidis, University of
Cologne, Robert-Koch-Str.
39, 50931 Cologne, Germany
- Center
for Molecular Medicine Cologne (CMMC), University
of Cologne, 50931 Cologne, Germany
| | - Rosemarie Marchan
- Leibniz
Research Centre for Working Environment and Human Factors at the Technical
University of Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Karolina Edlund
- Leibniz
Research Centre for Working Environment and Human Factors at the Technical
University of Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
| | - Marcel Leist
- In
Vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Universitätsstr. 10, P.O.
Box M657, 78457 Konstanz, Germany
| | - Jörg Rahnenführer
- Department
of Statistics, TU Dortmund University, Vogelpothsweg 87, 44227 Dortmund, Germany
| | - Agapios Sachinidis
- Faculty
of Medicine and University Hospital Cologne, Center for Physiology,
Working Group Sachinidis, University of
Cologne, Robert-Koch-Str.
39, 50931 Cologne, Germany
- Center
for Molecular Medicine Cologne (CMMC), University
of Cologne, 50931 Cologne, Germany
| | - Jan G. Hengstler
- Leibniz
Research Centre for Working Environment and Human Factors at the Technical
University of Dortmund (IfADo), Ardeystrasse 67, 44139 Dortmund, Germany
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9
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Manuela J, David ZJ, Nicole S, Nicole C, Paul B, Erich K, Lisa SP, Claudia M, Marcel L, Stefan K. Optimization of the TeraTox assay for preclinical teratogenicity assessment. Toxicol Sci 2022; 188:17-33. [PMID: 35485993 PMCID: PMC9237991 DOI: 10.1093/toxsci/kfac046] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Current animal-free methods to assess teratogenicity of drugs under development still deliver high numbers of false negatives. To improve the sensitivity of human teratogenicity prediction, we characterized the TeraTox test, a newly developed multilineage differentiation assay using 3D human-induced pluripotent stem cells. TeraTox produces primary output concentration-dependent cytotoxicity and altered gene expression induced by each test compound. These data are fed into an interpretable machine-learning model to perform prediction, which relates to the concentration-dependent human teratogenicity potential of drug candidates. We applied TeraTox to profile 33 approved pharmaceuticals and 12 proprietary drug candidates with known in vivo data. Comparing TeraTox predictions with known human or animal toxicity, we report an accuracy of 69% (specificity: 53%, sensitivity: 79%). TeraTox performed better than 2 quantitative structure-activity relationship models and had a higher sensitivity than the murine embryonic stem cell test (accuracy: 58%, specificity: 76%, and sensitivity: 46%) run in the same laboratory. The overall prediction accuracy could be further improved by combining TeraTox and mouse embryonic stem cell test results. Furthermore, patterns of altered gene expression revealed by TeraTox may help grouping toxicologically similar compounds and possibly deducing common modes of action. The TeraTox assay and the dataset described here therefore represent a new tool and a valuable resource for drug teratogenicity assessment.
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Affiliation(s)
- Jaklin Manuela
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland.,Department for In Vitro Toxicology and Biomedicine Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Germany
| | - Zhang Jitao David
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
| | - Schäfer Nicole
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
| | - Clemann Nicole
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
| | - Barrow Paul
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
| | - Küng Erich
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
| | - Sach-Peltason Lisa
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
| | | | - Leist Marcel
- Department for In Vitro Toxicology and Biomedicine Inaugurated by the Doerenkamp-Zbinden Foundation, University of Konstanz, Germany
| | - Kustermann Stefan
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Switzerland
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10
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Shafique S. Stem cell-based region-specific brain organoids: Novel models to understand neurodevelopmental defects. Birth Defects Res 2022; 114:1003-1013. [PMID: 35332709 DOI: 10.1002/bdr2.2004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 03/07/2022] [Accepted: 03/11/2022] [Indexed: 11/08/2022]
Abstract
The study of human brain development and neurodevelopmental defects has remained challenging so far due to unique, specific, and complex underlying processes. Recent advances in the technologies and protocols of in vitro human brain organoid development have led to immense possibilities of understanding these processes. Human brain organoids are stem-cell derived three-dimensional in vitro tissues that resemble the developing fetal brain. Major advances in stem cell techniques pioneering the development of in vitro human brain development include reprogramming human somatic cells into induced pluripotent cells (iPSCs) followed by the targeted differentiation of iPSCs into the cells of three embryonic germ cell layers. The neural progenitor cells produced by the directed differentiation of iPSCs undergo some level of self-organization to generate in vitro human brain like tissue. A three-dimensional differentiation approach applied to create region-specific brain organoids has successfully led to develop highly specialized cortical, forebrain, pallium, and subpallium in vitro human brain organoid models. These stem cell-based brain organoids are novel models to study human brain development, neurodevelopmental defects, chemical toxicity testing, and drug repurposing screening. This review focuses on the fundamentals of brain organoid development and applications. The novel applications of using cortical organoids in understanding the mechanisms of Zika virus-induced microcephaly, congenital microcephaly, and lissencephaly are also discussed.
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Affiliation(s)
- Sidra Shafique
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
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11
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Giambò F, Leone GM, Gattuso G, Rizzo R, Cosentino A, Cinà D, Teodoro M, Costa C, Tsatsakis A, Fenga C, Falzone L. Genetic and Epigenetic Alterations Induced by Pesticide Exposure: Integrated Analysis of Gene Expression, microRNA Expression, and DNA Methylation Datasets. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18168697. [PMID: 34444445 PMCID: PMC8394939 DOI: 10.3390/ijerph18168697] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/12/2021] [Accepted: 08/16/2021] [Indexed: 02/07/2023]
Abstract
Environmental or occupational exposure to pesticides is considered one of the main risk factors for the development of various diseases. Behind the development of pesticide-associated pathologies, there are both genetic and epigenetic alterations, where these latter are mainly represented by the alteration in the expression levels of microRNAs and by the change in the methylation status of the DNA. At present, no studies have comprehensively evaluated the genetic and epigenetic alterations induced by pesticides; therefore, the aim of the present study was to identify modifications in gene miRNA expression and DNA methylation useful for the prediction of pesticide exposure. For this purpose, an integrated analysis of gene expression, microRNA expression, and DNA methylation datasets obtained from the GEO DataSets database was performed to identify putative genes, microRNAs, and DNA methylation hotspots associated with pesticide exposure and responsible for the development of different diseases. In addition, DIANA-miRPath, STRING, and GO Panther prediction tools were used to establish the functional role of the putative biomarkers identified. The results obtained demonstrated that pesticides can modulate the expression levels of different genes and induce different epigenetic alterations in the expression levels of miRNAs and in the modulation of DNA methylation status.
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Affiliation(s)
- Federica Giambò
- CEMAD Digestive Disease Center, Fondazione Policlinico Universitario “A. Gemelli” IRCCS, Università Cattolica del Sacro Cuore, 00168 Roma, Italy;
| | - Gian Marco Leone
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (G.M.L.); (G.G.); (R.R.); (A.C.)
| | - Giuseppe Gattuso
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (G.M.L.); (G.G.); (R.R.); (A.C.)
| | - Roberta Rizzo
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (G.M.L.); (G.G.); (R.R.); (A.C.)
| | - Alessia Cosentino
- Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy; (G.M.L.); (G.G.); (R.R.); (A.C.)
| | - Diana Cinà
- Health Management of the “Cannizzaro” Emergency Hospital of Catania, 95126 Catania, Italy;
- Clinical Pathology and Clinical Molecular Biology Unit, “Garibaldi Centro” Hospital, ARNAS Garibaldi, 95123 Catania, Italy
| | - Michele Teodoro
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Occupational Medicine Section, University of Messina, 98125 Messina, Italy; (M.T.); (C.F.)
| | - Chiara Costa
- Clinical and Experimental Medicine Department, University of Messina, 98125 Messina, Italy;
| | - Aristides Tsatsakis
- Department of Forensic Sciences and Toxicology, Faculty of Medicine, University of Crete, 71003 Heraklion, Greece;
| | - Concettina Fenga
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Occupational Medicine Section, University of Messina, 98125 Messina, Italy; (M.T.); (C.F.)
| | - Luca Falzone
- Epidemiology and Biostatistics Unit, National Cancer Institute-IRCCS ‘Fondazione G. Pascale’, 80131 Naples, Italy
- Correspondence: ; Tel.: +39-095-478-1278
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12
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Bhol CS, Patil S, Sahu BB, Patra SK, Bhutia SK. The clinical significance and correlative signaling pathways of paired box gene 9 in development and carcinogenesis. Biochim Biophys Acta Rev Cancer 2021; 1876:188561. [PMID: 33965511 DOI: 10.1016/j.bbcan.2021.188561] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/29/2021] [Accepted: 04/29/2021] [Indexed: 12/17/2022]
Abstract
Paired box 9 (PAX9) gene belongs to the PAX family, which encodes a family of metazoan transcription factors documented by a conserved DNA binding paired domain 128-amino-acids, critically essential for physiology and development. It is primarily expressed in embryonic tissues, such as the pharyngeal pouch endoderm, somites, neural crest-derived mesenchyme, and distal limb buds. PAX9 plays a vital role in craniofacial development by maintaining the odontogenic potential, mutations, and polymorphisms associated with the risk of tooth agenesis, hypodontia, and crown size in dentition. The loss-of-function of PAX9 in the murine model resulted in a short life span due to the arrest of cleft palate formation and skeletal abnormalities. According to recent studies, the PAX9 gene has a significant role in maintaining squamous cell differentiation, odontoblast differentiation of pluripotent stem cells, deregulation of which is associated with tumor initiation, and malignant transformation. Moreover, PAX9 contributes to promoter hypermethylation and alcohol- induced oro-esophageal squamous cell carcinoma mediated by downregulation of differentiation and apoptosis. Likewise, PAX9 activation is also reported to be associated with drug sensitivity. In summary, this current review aims to understand PAX9 function in the regulation of development, differentiation, and carcinogenesis, along with the underlying signaling pathways for possible cancer therapeutics.
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Affiliation(s)
- Chandra Sekhar Bhol
- Cancer and Cell Death Laboratory, Department of Life Science, National Institute of Technology Rourkela, Rourkela, 769008, Odisha, India
| | - Shankargouda Patil
- Department of Maxillofacial Surgery and Diagnostic Sciences, Division of Oral Pathology, College of Dentistry, Jazan University, Jazan, Saudi Arabia
| | - Binod Bihari Sahu
- Plant Immunity Laboratory, Department of Life Science, National Institute of Technology Rourkela, Rourkela, 769008, Odisha, India
| | - Samir Kumar Patra
- Epigenetics and Cancer Research Laboratory, Department of Life Science, National Institute of Technology Rourkela, Rourkela, 769008, Odisha, India
| | - Sujit Kumar Bhutia
- Cancer and Cell Death Laboratory, Department of Life Science, National Institute of Technology Rourkela, Rourkela, 769008, Odisha, India.
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13
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Seidel F. Reproductive toxicity of benzophenone-3. Arch Toxicol 2020; 94:3593-3594. [PMID: 32918560 DOI: 10.1007/s00204-020-02865-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 08/10/2020] [Indexed: 11/29/2022]
Affiliation(s)
- Florian Seidel
- Leibniz Research Centre for Working Environment and Human Factors, Ardeystr 67, 44139, Dortmund, Germany.
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14
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Aluminium affects neurospheres at human in vivo relevant concentrations. Arch Toxicol 2020; 94:3601-3602. [PMID: 32840640 DOI: 10.1007/s00204-020-02889-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 10/23/2022]
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15
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The EU-ToxRisk method documentation, data processing and chemical testing pipeline for the regulatory use of new approach methods. Arch Toxicol 2020; 94:2435-2461. [PMID: 32632539 PMCID: PMC7367925 DOI: 10.1007/s00204-020-02802-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 06/03/2020] [Indexed: 12/17/2022]
Abstract
Hazard assessment, based on new approach methods (NAM), requires the use of batteries of assays, where individual tests may be contributed by different laboratories. A unified strategy for such collaborative testing is presented. It details all procedures required to allow test information to be usable for integrated hazard assessment, strategic project decisions and/or for regulatory purposes. The EU-ToxRisk project developed a strategy to provide regulatorily valid data, and exemplified this using a panel of > 20 assays (with > 50 individual endpoints), each exposed to 19 well-known test compounds (e.g. rotenone, colchicine, mercury, paracetamol, rifampicine, paraquat, taxol). Examples of strategy implementation are provided for all aspects required to ensure data validity: (i) documentation of test methods in a publicly accessible database; (ii) deposition of standard operating procedures (SOP) at the European Union DB-ALM repository; (iii) test readiness scoring accoding to defined criteria; (iv) disclosure of the pipeline for data processing; (v) link of uncertainty measures and metadata to the data; (vi) definition of test chemicals, their handling and their behavior in test media; (vii) specification of the test purpose and overall evaluation plans. Moreover, data generation was exemplified by providing results from 25 reporter assays. A complete evaluation of the entire test battery will be described elsewhere. A major learning from the retrospective analysis of this large testing project was the need for thorough definitions of the above strategy aspects, ideally in form of a study pre-registration, to allow adequate interpretation of the data and to ensure overall scientific/toxicological validity.
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16
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Cerrizuela S, Vega-Lopez GA, Aybar MJ. The role of teratogens in neural crest development. Birth Defects Res 2020; 112:584-632. [PMID: 31926062 DOI: 10.1002/bdr2.1644] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 12/11/2019] [Accepted: 12/22/2019] [Indexed: 12/13/2022]
Abstract
The neural crest (NC), discovered by Wilhelm His 150 years ago, gives rise to a multipotent migratory embryonic cell population that generates a remarkably diverse and important array of cell types during the development of the vertebrate embryo. These cells originate in the neural plate border (NPB), which is the ectoderm between the neural plate and the epidermis. They give rise to the neurons and glia of the peripheral nervous system, melanocytes, chondrocytes, smooth muscle cells, odontoblasts and neuroendocrine cells, among others. Neurocristopathies are a class of congenital diseases resulting from the abnormal induction, specification, migration, differentiation or death of NC cells (NCCs) during embryonic development and have an important medical and societal impact. In general, congenital defects affect an appreciable percentage of newborns worldwide. Some of these defects are caused by teratogens, which are agents that negatively impact the formation of tissues and organs during development. In this review, we will discuss the teratogens linked to the development of many birth defects, with a strong focus on those that specifically affect the development of the NC, thereby producing neurocristopathies. Although increasing attention is being paid to the effect of teratogens on embryonic development in general, there is a strong need to critically evaluate the specific role of these agents in NC development. Therefore, increased understanding of the role of these factors in NC development will contribute to the planning of strategies aimed at the prevention and treatment of human neurocristopathies, whose etiology was previously not considered.
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Affiliation(s)
- Santiago Cerrizuela
- Área Biología Experimental, Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT), Tucumán, Argentina.,Instituto de Biología "Dr. Francisco D. Barbieri", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Tucumán, Argentina
| | - Guillermo A Vega-Lopez
- Área Biología Experimental, Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT), Tucumán, Argentina.,Instituto de Biología "Dr. Francisco D. Barbieri", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Tucumán, Argentina
| | - Manuel J Aybar
- Área Biología Experimental, Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT), Tucumán, Argentina.,Instituto de Biología "Dr. Francisco D. Barbieri", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Tucumán, Argentina
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17
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Development of a neural rosette formation assay (RoFA) to identify neurodevelopmental toxicants and to characterize their transcriptome disturbances. Arch Toxicol 2019; 94:151-171. [PMID: 31712839 DOI: 10.1007/s00204-019-02612-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 11/05/2019] [Indexed: 12/18/2022]
Abstract
The first in vitro tests for developmental toxicity made use of rodent cells. Newer teratology tests, e.g. developed during the ESNATS project, use human cells and measure mechanistic endpoints (such as transcriptome changes). However, the toxicological implications of mechanistic parameters are hard to judge, without functional/morphological endpoints. To address this issue, we developed a new version of the human stem cell-based test STOP-tox(UKN). For this purpose, the capacity of the cells to self-organize to neural rosettes was assessed as functional endpoint: pluripotent stem cells were allowed to differentiate into neuroepithelial cells for 6 days in the presence or absence of toxicants. Then, both transcriptome changes were measured (standard STOP-tox(UKN)) and cells were allowed to form rosettes. After optimization of staining methods, an imaging algorithm for rosette quantification was implemented and used for an automated rosette formation assay (RoFA). Neural tube toxicants (like valproic acid), which are known to disturb human development at stages when rosette-forming cells are present, were used as positive controls. Established toxicants led to distinctly different tissue organization and differentiation stages. RoFA outcome and transcript changes largely correlated concerning (1) the concentration-dependence, (2) the time dependence, and (3) the set of positive hits identified amongst 24 potential toxicants. Using such comparative data, a prediction model for the RoFA was developed. The comparative analysis was also used to identify gene dysregulations that are particularly predictive for disturbed rosette formation. This 'RoFA predictor gene set' may be used for a simplified and less costly setup of the STOP-tox(UKN) assay.
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18
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Fritsche E, Barenys M, Klose J, Masjosthusmann S, Nimtz L, Schmuck M, Wuttke S, Tigges J. Current Availability of Stem Cell-Based In Vitro Methods for Developmental Neurotoxicity (DNT) Testing. Toxicol Sci 2019; 165:21-30. [PMID: 29982830 DOI: 10.1093/toxsci/kfy178] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
There is evidence that chemical exposure during development can cause irreversible impairments of the human developing nervous system. Therefore, testing compounds for their developmentally neurotoxic potential has high priority for different stakeholders: academia, industry, and regulatory bodies. Due to the resource-intensity of current developmental neurotoxicity (DNT) in vivo guidelines, alternative methods that are scientifically valid and have a high predictivity for humans are especially desired by regulators. Here, we review availability of stem-/progenitor cell-based in vitro methods for DNT evaluation that is based on the concept of neurodevelopmental process assessment. These test methods are assembled into a DNT in vitro testing battery. Gaps in this testing battery addressing research needs are also pointed out.
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Affiliation(s)
| | - Marta Barenys
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
| | - Jördis Klose
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
| | - Stefan Masjosthusmann
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
| | - Laura Nimtz
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
| | - Martin Schmuck
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
| | - Saskia Wuttke
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
| | - Julia Tigges
- IUF - Leibniz Research Institute for Environmental Medicine 40225, Düsseldorf, Germany
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19
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Li J, Settivari R, LeBaron MJ, Marty MS. An industry perspective: A streamlined screening strategy using alternative models for chemical assessment of developmental neurotoxicity. Neurotoxicology 2019; 73:17-30. [DOI: 10.1016/j.neuro.2019.02.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 02/14/2019] [Accepted: 02/14/2019] [Indexed: 12/22/2022]
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20
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Mukhopadhyay P, Seelan RS, Greene RM, Pisano MM. Impact of prenatal arsenate exposure on gene expression in a pure population of migratory cranial neural crest cells. Reprod Toxicol 2019; 86:76-85. [PMID: 30953684 DOI: 10.1016/j.reprotox.2019.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 03/29/2019] [Accepted: 04/02/2019] [Indexed: 11/27/2022]
Abstract
Prenatal exposure to arsenic, a naturally occurring toxic element, causes neural tube defects (NTDs) and, in animal models, orofacial anomalies. Since aberrant development or migration of cranial neural crest cells (CNCCs) can also cause similar anomalies within developing embryos, we examined the effects of in utero exposure to sodium arsenate on gene expression patterns in pure populations of CNCCs, isolated by fluorescence activated cell sorting (FACS), from Cre/LoxP reporter mice. Changes in gene expression were analyzed using Affymetrix GeneChip® microarrays and expression of selected genes was verified by TaqMan quantitative real-time PCR. We report, for the first time, arsenate-induced alterations in the expression of a number of novel candidate genes and canonical cascades that may contribute to the pathogenesis of orofacial defects. Ingenuity Pathway and NIH-DAVID analyses revealed cellular response pathways, biological themes, and potential upstream regulators, that may underlie altered fetal programming of arsenate exposed CNCCs.
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Affiliation(s)
- Partha Mukhopadhyay
- Department of Oral Immunology and Infectious Diseases, Division of Craniofacial Development and Anomalies, ULSD, University of Louisville, Louisville, KY 40202, United States
| | - Ratnam S Seelan
- Department of Oral Immunology and Infectious Diseases, Division of Craniofacial Development and Anomalies, ULSD, University of Louisville, Louisville, KY 40202, United States
| | - Robert M Greene
- Department of Oral Immunology and Infectious Diseases, Division of Craniofacial Development and Anomalies, ULSD, University of Louisville, Louisville, KY 40202, United States.
| | - M Michele Pisano
- Department of Oral Immunology and Infectious Diseases, Division of Craniofacial Development and Anomalies, ULSD, University of Louisville, Louisville, KY 40202, United States
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21
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Bolt HM. Highlight report: Cell type selection for toxicity testing. EXCLI JOURNAL 2019; 17:1180-1181. [PMID: 30713478 PMCID: PMC6341425 DOI: 10.17179/excli2018-2017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 11/13/2022]
Affiliation(s)
- H M Bolt
- IfADo - Leibniz Research Centre for Working Environment and Human Factors, Dortmund, GERMANY
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22
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Seidel F. Highlight report: Stem cell-based developmental toxicity tests. Arch Toxicol 2018; 92:3609-3610. [PMID: 30478605 DOI: 10.1007/s00204-018-2357-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 11/19/2018] [Indexed: 10/27/2022]
Affiliation(s)
- Florian Seidel
- IfADo, Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund, Ardeystr. 67, 44139, Dortmund, Germany.
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23
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Highlight report: the need of 'fit-for-purpose' controls for cell lines used in toxicity assays. Arch Toxicol 2018; 92:3605-3606. [PMID: 30430188 DOI: 10.1007/s00204-018-2348-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 11/08/2018] [Indexed: 10/27/2022]
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24
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Giordano M, Tripathi KP, Guarracino MR. Ensemble of rankers for efficient gene signature extraction in smoke exposure classification. BMC Bioinformatics 2018. [PMID: 29536823 PMCID: PMC5850943 DOI: 10.1186/s12859-018-2035-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background System toxicology aims at understanding the mechanisms used by biological systems to respond to toxicants. Such understanding can be leveraged to assess the risk of chemicals, drugs, and consumer products in living organisms. In system toxicology, machine learning techniques and methodologies are applied to develop prediction models for classification of toxicant exposure of biological systems. Gene expression data (RNA/DNA microarray) are often used to develop such prediction models. Results The outcome of the present work is an experimental methodology to develop prediction models, based on robust gene signatures, for the classification of cigarette smoke exposure and cessation in humans. It is a result of the participation in the recent sbv IMPROVER SysTox Computational Challenge. By merging different gene selection techniques, we obtain robust gene signatures and we investigate prediction capabilities of different off-the-shelf machine learning techniques, such as artificial neural networks, linear models and support vector machines. We also predict six novel genes in our signature, and firmly believe these genes have to be further investigated as biomarkers for tobacco smoking exposure. Conclusions The proposed methodology provides gene signatures with top-ranked performances in the prediction of the investigated classification methods, as well as new discoveries in genetic signatures for bio-markers of the smoke exposure of humans. Electronic supplementary material The online version of this article (10.1186/s12859-018-2035-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Maurizio Giordano
- High Performance Computing and Networking Institute (ICAR), National Council of Research (CNR), Naples, Italy.
| | - Kumar Parijat Tripathi
- High Performance Computing and Networking Institute (ICAR), National Council of Research (CNR), Naples, Italy
| | - Mario Rosario Guarracino
- High Performance Computing and Networking Institute (ICAR), National Council of Research (CNR), Naples, Italy
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25
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Bal-Price A, Hogberg HT, Crofton KM, Daneshian M, FitzGerald RE, Fritsche E, Heinonen T, Hougaard Bennekou S, Klima S, Piersma AH, Sachana M, Shafer TJ, Terron A, Monnet-Tschudi F, Viviani B, Waldmann T, Westerink RHS, Wilks MF, Witters H, Zurich MG, Leist M. Recommendation on test readiness criteria for new approach methods in toxicology: Exemplified for developmental neurotoxicity. ALTEX-ALTERNATIVES TO ANIMAL EXPERIMENTATION 2018; 35:306-352. [PMID: 29485663 DOI: 10.14573/altex.1712081] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 01/29/2018] [Indexed: 01/06/2023]
Abstract
Multiple non-animal-based test methods have never been formally validated. In order to use such new approach methods (NAMs) in a regulatory context, criteria to define their readiness are necessary. The field of developmental neurotoxicity (DNT) testing is used to exemplify the application of readiness criteria. The costs and number of untested chemicals are overwhelming for in vivo DNT testing. Thus, there is a need for inexpensive, high-throughput NAMs, to obtain initial information on potential hazards, and to allow prioritization for further testing. A background on the regulatory and scientific status of DNT testing is provided showing different types of test readiness levels, depending on the intended use of data from NAMs. Readiness criteria, compiled during a stakeholder workshop, uniting scientists from academia, industry and regulatory authorities are presented. An important step beyond the listing of criteria, was the suggestion for a preliminary scoring scheme. On this basis a (semi)-quantitative analysis process was assembled on test readiness of 17 NAMs with respect to various uses (e.g. prioritization/screening, risk assessment). The scoring results suggest that several assays are currently at high readiness levels. Therefore, suggestions are made on how DNT NAMs may be assembled into an integrated approach to testing and assessment (IATA). In parallel, the testing state in these assays was compiled for more than 1000 compounds. Finally, a vision is presented on how further NAM development may be guided by knowledge of signaling pathways necessary for brain development, DNT pathophysiology, and relevant adverse outcome pathways (AOP).
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Affiliation(s)
- Anna Bal-Price
- European Commission, Joint Research Centre (EC JRC), Ispra (VA), Italy
| | - Helena T Hogberg
- Center for Alternatives to Animal Testing (CAAT), Johns Hopkins University, Baltimore, MD, USA
| | - Kevin M Crofton
- National Centre for Computational Toxicology, US EPA, RTP, Washington, NC, USA
| | - Mardas Daneshian
- Center for Alternatives to Animal Testing, CAAT-Europe, University of Konstanz, Konstanz, Germany
| | - Rex E FitzGerald
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland
| | - Ellen Fritsche
- IUF - Leibniz Research Institute for Environmental Medicine & Heinrich-Heine-University, Düsseldorf, Germany
| | - Tuula Heinonen
- Finnish Centre for Alternative Methods (FICAM), University of Tampere, Tampere, Finland
| | | | - Stefanie Klima
- In vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Aldert H Piersma
- RIVM, National Institute for Public Health and the Environment, Bilthoven, and Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Magdalini Sachana
- Organisation for Economic Co-operation and Development (OECD), Paris, France
| | - Timothy J Shafer
- National Centre for Computational Toxicology, US EPA, RTP, Washington, NC, USA
| | | | - Florianne Monnet-Tschudi
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland.,Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Barbara Viviani
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Italy
| | - Tanja Waldmann
- In vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Konstanz, Germany
| | - Remco H S Westerink
- Neurotoxicology Research Group, Institute for Risk Assessment Sciences (IRAS), Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Martin F Wilks
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland
| | - Hilda Witters
- VITO, Flemish Institute for Technological Research, Unit Environmental Risk and Health, Mol, Belgium
| | - Marie-Gabrielle Zurich
- Swiss Centre for Human Applied Toxicology, SCAHT, University of Basle, Switzerland.,Department of Physiology, University of Lausanne, Lausanne, Switzerland
| | - Marcel Leist
- Center for Alternatives to Animal Testing, CAAT-Europe, University of Konstanz, Konstanz, Germany.,In vitro Toxicology and Biomedicine, Department of Biology, University of Konstanz, Konstanz, Germany
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26
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Leist M. New animal-free concepts and test methods for developmental toxicity and peripheral neurotoxicity. Altern Lab Anim 2017; 45:253-260. [PMID: 29112453 DOI: 10.1177/026119291704500505] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The complex toxicological fields of repeat dose organ toxicity (RDT) and developmental and reproductive toxicity (DART) still require new concepts and approaches to achieve a fully animal-free safety assessment of chemicals. One novel approach is the generation of relevant human cell types from pluripotent stem cells, and the use of such cells for the establishment of phenotypic test methods. Due to their broad endpoints, such tests capture multiple types of toxicants, i.e. they are a readout for the activation of many adverse outcome pathways (AOPs). The 2016 Lush Science Prize was awarded for the development of one such assay, the PeriTox test, which uses human peripheral neurons generated from stem cells. The assay endpoints measure various cell functions, and these give information on the potential neurotoxicity and developmental neurotoxicity hazard of test compounds. The PeriTox test method has a high predictivity and sensitivity for peripheral neurotoxicants, and thus addresses the inherent challenges in pesticide testing and drug development. Data from the test can be obtained quickly and at a relatively high-throughput, and thus, the assay has the potential to replace animal-based safety assessment during early product development or for screening potential environmental toxicants.
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Affiliation(s)
- Marcel Leist
- In Vitro Toxicology and Biomedicine Laboratory, Department of Biology, University of Konstanz, Konstanz, Germany; CAAT-Europe, University of Konstanz, Konstanz, Germany; Konstanz Research School Chemical Biology, Konstanz, Germany; Co-operative Research Training Group on In Vitro Testing of Active Ingredients, Konstanz-Sigmaringen, Germany
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27
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Dhanani KCH, Samson WJ, Edkins AL. Fibronectin is a stress responsive gene regulated by HSF1 in response to geldanamycin. Sci Rep 2017; 7:17617. [PMID: 29247221 PMCID: PMC5732156 DOI: 10.1038/s41598-017-18061-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 12/02/2017] [Indexed: 01/16/2023] Open
Abstract
Fibronectin is an extracellular matrix glycoprotein with key roles in cell adhesion and migration. Hsp90 binds directly to fibronectin and Hsp90 depletion regulates fibronectin matrix stability. Where inhibition of Hsp90 with a C-terminal inhibitor, novobiocin, reduced the fibronectin matrix, treatment with an N-terminal inhibitor, geldanamycin, increased fibronectin levels. Geldanamycin treatment induced a stress response and a strong dose and time dependent increase in fibronectin mRNA via activation of the fibronectin promoter. Three putative heat shock elements (HSEs) were identified in the fibronectin promoter. Loss of two of these HSEs reduced both basal and geldanamycin-induced promoter activity, as did inhibition of the stress-responsive transcription factor HSF1. Binding of HSF1 to one of the putative HSE was confirmed by ChIP under basal conditions, and occupancy shown to increase with geldanamycin treatment. These data support the hypothesis that fibronectin is stress-responsive and a functional HSF1 target gene. COLA42 and LAMB3 mRNA levels were also increased with geldanamycin indicating that regulation of extracellular matrix (ECM) genes by HSF1 may be a wider phenomenon. Taken together, these data have implications for our understanding of ECM dynamics in stress-related diseases in which HSF1 is activated, and where the clinical application of N-terminal Hsp90 inhibitors is intended.
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Affiliation(s)
- Karim Colin Hassan Dhanani
- Biomedical Biotechnology Research Unit (BioBRU), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa
| | - William John Samson
- Biomedical Biotechnology Research Unit (BioBRU), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa
| | - Adrienne Lesley Edkins
- Biomedical Biotechnology Research Unit (BioBRU), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa.
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28
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Bolt HM. Stem cells in toxicological research. Arch Toxicol 2017; 91:4029-4030. [PMID: 29143079 DOI: 10.1007/s00204-017-2120-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 11/13/2017] [Indexed: 11/25/2022]
Affiliation(s)
- Hermann M Bolt
- IfADo-Leibniz Research Centre for Working Environment and Human Factors at TU Dortmund, Ardeystr. 67, 44139, Dortmund, Germany.
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29
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Kugler J, Huhse B, Tralau T, Luch A. Embryonic stem cells and the next generation of developmental toxicity testing. Expert Opin Drug Metab Toxicol 2017; 13:833-841. [PMID: 28675072 DOI: 10.1080/17425255.2017.1351548] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION The advent of stem cell technology has seen the establishment of embryonic stem cells (ESCs) as molecular model systems and screening tools. Although ESCs are nowadays widely used in research, regulatory implementation for developmental toxicity testing is pending. Areas Covered: This review evaluates the performance of current ESC, including human (h)ESC testing systems, trying to elucidate their potential for developmental toxicity testing. It shall discuss defining parameters and mechanisms, their relevance and contemplate what can realistically be expected. Crucially this includes the question of how to ascertain the quality of currently employed cell lines and tests based thereon. Finally, the use of hESCs will raise ethical concerns which should be addressed early on. Expert Opinion: While the suitability of (h)ESCs as tools for research and development goes undisputed, any routine use for developmental toxicity testing currently still seems premature. The reasons for this comprise inherent biological deficiencies as well as cell line quality and system validation. Overcoming these issues will require collaboration of scientists, test developers and regulators. Also, validation needs to be made worthwhile for academia. Finally we have to continuously rethink existing strategies, making room for improved testing and innovative approaches.
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Affiliation(s)
- Josephine Kugler
- a Department of Chemical & Product Safety , German Federal Institute for Risk Assessment (BfR) , Berlin , Germany
| | - Bettina Huhse
- a Department of Chemical & Product Safety , German Federal Institute for Risk Assessment (BfR) , Berlin , Germany
| | - Tewes Tralau
- a Department of Chemical & Product Safety , German Federal Institute for Risk Assessment (BfR) , Berlin , Germany
| | - Andreas Luch
- a Department of Chemical & Product Safety , German Federal Institute for Risk Assessment (BfR) , Berlin , Germany
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30
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Bond GG, Dietrich DR. Human cost burden of exposure to endocrine disrupting chemicals. A critical review. Arch Toxicol 2017; 91:2745-2762. [PMID: 28528477 DOI: 10.1007/s00204-017-1985-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/08/2017] [Indexed: 01/01/2023]
Abstract
Recently published papers have alleged that exposures to endocrine disrupting chemicals (EDCs) are causing substantial disease burdens in the EU and US and are consequently costing society hundreds of billions of dollars annually. To date, these cost estimates have not undergone adequate scientific scrutiny, but nevertheless are being used aggressively in advocacy campaigns in an attempt to fundamentally change how chemicals are tested, evaluated and regulated. Consequently, we critically evaluated the underlying methodology and assumptions employed by the chief architects of the disease burden cost estimates. Since the vast majority of their assigned disease burden costs are driven by the assumption that "loss of IQ" and "increased prevalence of intellectual disability" are caused by exposures to organophosphate pesticides (OPPs) and brominated flame retardants (PBDEs), we have taken special care in describing and evaluating the underlying toxicology and epidemiology evidence that was relied upon. Unfortunately, our review uncovered substantial flaws in the approach taken and the conclusions that were drawn. Indeed, the authors of these papers assumed causal relationships between putative exposures to EDCs and selected diseases, i.e., "loss of IQ" and "increased prevalence of intellectual disability", despite not having established them via a thorough evaluation of the strengths and weaknesses of the underlying animal toxicology and human epidemiology evidence. Consequently, the assigned disease burden costs are highly speculative and should not be considered in the weight of evidence approach underlying any serious policy discussions serving to protect the public and regulate chemicals considered as EDCs.
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Affiliation(s)
| | - Daniel R Dietrich
- Human and Environmental Toxicology, University of Konstanz, Constance, Germany
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31
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Combination of multiple neural crest migration assays to identify environmental toxicants from a proof-of-concept chemical library. Arch Toxicol 2017; 91:3613-3632. [PMID: 28477266 DOI: 10.1007/s00204-017-1977-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Accepted: 04/26/2017] [Indexed: 12/18/2022]
Abstract
Many in vitro tests have been developed to screen for potential neurotoxicity. However, only few cell function-based tests have been used for comparative screening, and thus experience is scarce on how to confirm and evaluate screening hits. We addressed these questions for the neural crest cell migration test (cMINC). After an initial screen, a hit follow-up strategy was devised. A library of 75 compounds plus internal controls (NTP80-list), assembled by the National Toxicology Program of the USA (NTP) was used. It contained some known classes of (developmental) neurotoxic compounds. The primary screen yielded 23 confirmed hits, which comprised ten flame retardants, seven pesticides and six drug-like compounds. Comparison of concentration-response curves for migration and viability showed that all hits were specific. The extent to which migration was inhibited was 25-90%, and two organochlorine pesticides (DDT, heptachlor) were most efficient. In the second part of this study, (1) the cMINC assay was repeated under conditions that prevent proliferation; (2) a transwell migration assay was used as a different type of migration assay; (3) cells were traced to assess cell speed. Some toxicants had largely varying effects between assays, but each hit was confirmed in at least one additional test. This comparative study allows an estimate on how confidently the primary hits from a cell function-based screen can be considered as toxicants disturbing a key neurodevelopmental process. Testing of the NTP80-list in more assays will be highly interesting to assemble a test battery and to build prediction models for developmental toxicity.
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32
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Impairment of human neural crest cell migration by prolonged exposure to interferon-beta. Arch Toxicol 2017; 91:3385-3402. [PMID: 28365849 PMCID: PMC5608792 DOI: 10.1007/s00204-017-1966-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 03/21/2017] [Indexed: 12/31/2022]
Abstract
Human cell-based toxicological assays have been used successfully to detect known toxicants, and to distinguish them from negative controls. However, there is at present little experience on how to deal with hits from screens of compounds with yet unknown hazard. As a case study to this issue, we characterized human interferon-beta (IFNβ) as potential developmental toxicant affecting neural crest cells (NCC). The protein was identified as a hit during a screen of clinically used drugs in the ‘migration inhibition of neural crest’ (MINC) assay. Concentration–response studies in the MINC combined with immunocytochemistry and mRNA quantification of cellular markers showed that IFNβ inhibited NCC migration at concentrations as low as 20 pM. The effective concentrations found here correspond to levels found in human plasma, and they were neither cytostatic nor cytotoxic nor did they did they affect the differentiation state and overall phenotype of NCC. Data from two other migration assays confirmed that picomolar concentration of IFNβ reduced the motility of NCC, while other interferons were less potent. The activation of JAK kinase by IFNβ, as suggested by bioinformatics analysis of the transcriptome changes, was confirmed by biochemical methods. The degree and duration of pathway activation correlated with the extent of migration inhibition, and pharmacological block of this signaling pathway before, or up to 6 h after exposure to the cytokine prevented the effects of IFNβ on migration. Thus, the reduction of vital functions of human NCC is a hitherto unknown potential hazard of endogenous or pharmacologically applied interferons.
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33
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Waldmann T, Grinberg M, König A, Rempel E, Schildknecht S, Henry M, Holzer AK, Dreser N, Shinde V, Sachinidis A, Rahnenführer J, Hengstler JG, Leist M. Stem Cell Transcriptome Responses and Corresponding Biomarkers That Indicate the Transition from Adaptive Responses to Cytotoxicity. Chem Res Toxicol 2016; 30:905-922. [PMID: 28001369 DOI: 10.1021/acs.chemrestox.6b00259] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Analysis of transcriptome changes has become an established method to characterize the reaction of cells to toxicants. Such experiments are mostly performed at compound concentrations close to the cytotoxicity threshold. At present, little information is available on concentration-dependent features of transcriptome changes, in particular, at the transition from noncytotoxic concentrations to conditions that are associated with cell death. Thus, it is unclear in how far cell death confounds the results of transcriptome studies. To explore this gap of knowledge, we treated pluripotent stem cells differentiating to human neuroepithelial cells (UKN1 assay) for short periods (48 h) with increasing concentrations of valproic acid (VPA) and methyl mercury (MeHg), two compounds with vastly different modes of action. We developed various visualization tools to describe cellular responses, and the overall response was classified as "tolerance" (minor transcriptome changes), "functional adaptation" (moderate/strong transcriptome responses, but no cytotoxicity), and "degeneration". The latter two conditions were compared, using various statistical approaches. We identified (i) genes regulated at cytotoxic, but not at noncytotoxic, concentrations and (ii) KEGG pathways, gene ontology term groups, and superordinate biological processes that were only regulated at cytotoxic concentrations. The consensus markers and processes found after 48 h treatment were then overlaid with those found after prolonged (6 days) treatment. The study highlights the importance of careful concentration selection and of controlling viability for transcriptome studies. Moreover, it allowed identification of 39 candidate "biomarkers of cytotoxicity". These could serve to provide alerts that data sets of interest may have been affected by cell death in the model system studied.
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Affiliation(s)
- Tanja Waldmann
- In Vitro Toxicology and Biomedicine, Department inaugurated by the Doerenkamp-Zbinden Chair Foundation, University of Konstanz , 78457 Konstanz, Germany
| | - Marianna Grinberg
- Department of Statistics, Technical University of Dortmund , D-44221 Dortmund, Germany
| | - André König
- Department of Statistics, Technical University of Dortmund , D-44221 Dortmund, Germany
| | - Eugen Rempel
- Department of Statistics, Technical University of Dortmund , D-44221 Dortmund, Germany
| | - Stefan Schildknecht
- In Vitro Toxicology and Biomedicine, Department inaugurated by the Doerenkamp-Zbinden Chair Foundation, University of Konstanz , 78457 Konstanz, Germany
| | - Margit Henry
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne (UKK) , D-50931 Cologne, Germany
| | - Anna-Katharina Holzer
- In Vitro Toxicology and Biomedicine, Department inaugurated by the Doerenkamp-Zbinden Chair Foundation, University of Konstanz , 78457 Konstanz, Germany
| | - Nadine Dreser
- In Vitro Toxicology and Biomedicine, Department inaugurated by the Doerenkamp-Zbinden Chair Foundation, University of Konstanz , 78457 Konstanz, Germany
| | - Vaibhav Shinde
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne (UKK) , D-50931 Cologne, Germany
| | - Agapios Sachinidis
- Center of Physiology and Pathophysiology, Institute of Neurophysiology, University of Cologne (UKK) , D-50931 Cologne, Germany
| | - Jörg Rahnenführer
- Department of Statistics, Technical University of Dortmund , D-44221 Dortmund, Germany
| | - Jan G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), Technical University of Dortmund , D-44139 Dortmund, Germany
| | - Marcel Leist
- In Vitro Toxicology and Biomedicine, Department inaugurated by the Doerenkamp-Zbinden Chair Foundation, University of Konstanz , 78457 Konstanz, Germany
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Yao X, Yin N, Faiola F. Stem cell toxicology: a powerful tool to assess pollution effects on human health. Natl Sci Rev 2016. [DOI: 10.1093/nsr/nww089] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AbstractEnvironmental pollution is a global problem; the lack of comprehensive toxicological assessments may lead to increased health risks. To fully understand the health effects of pollution, it is paramount to implement fast, efficient and specific toxicity screening that relies on human models rather than on time-consuming, expensive and often inaccurate tests involving live animals. Human stem cell toxicology represents a valid alternative to traditional toxicity assays because it takes advantage of the ability of stem cells to differentiate into multiple cell types and tissues of the human body. Thus, this branch of toxicology provides a possibility to assess cellular, embryonic, developmental, reproductive and functional toxicity in vitro within a single system highly relevant to human physiology. In this review, we describe the development, performance and future perspectives of stem cell toxicology, with an emphasis on how it can meet the increasing challenges posed by environmental pollution in the modern world.
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Affiliation(s)
- Xinglei Yao
- Stake Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Nuoya Yin
- Stake Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Francesco Faiola
- Stake Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
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35
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Schmidt BZ, Lehmann M, Gutbier S, Nembo E, Noel S, Smirnova L, Forsby A, Hescheler J, Avci HX, Hartung T, Leist M, Kobolák J, Dinnyés A. In vitro acute and developmental neurotoxicity screening: an overview of cellular platforms and high-throughput technical possibilities. Arch Toxicol 2016; 91:1-33. [PMID: 27492622 DOI: 10.1007/s00204-016-1805-9] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 07/07/2016] [Indexed: 01/03/2023]
Abstract
Neurotoxicity and developmental neurotoxicity are important issues of chemical hazard assessment. Since the interpretation of animal data and their extrapolation to man is challenging, and the amount of substances with information gaps exceeds present animal testing capacities, there is a big demand for in vitro tests to provide initial information and to prioritize for further evaluation. During the last decade, many in vitro tests emerged. These are based on animal cells, human tumour cell lines, primary cells, immortalized cell lines, embryonic stem cells, or induced pluripotent stem cells. They differ in their read-outs and range from simple viability assays to complex functional endpoints such as neural crest cell migration. Monitoring of toxicological effects on differentiation often requires multiomics approaches, while the acute disturbance of neuronal functions may be analysed by assessing electrophysiological features. Extrapolation from in vitro data to humans requires a deep understanding of the test system biology, of the endpoints used, and of the applicability domains of the tests. Moreover, it is important that these be combined in the right way to assess toxicity. Therefore, knowledge on the advantages and disadvantages of all cellular platforms, endpoints, and analytical methods is essential when establishing in vitro test systems for different aspects of neurotoxicity. The elements of a test, and their evaluation, are discussed here in the context of comprehensive prediction of potential hazardous effects of a compound. We summarize the main cellular characteristics underlying neurotoxicity, present an overview of cellular platforms and read-out combinations assessing distinct parts of acute and developmental neurotoxicology, and highlight especially the use of stem cell-based test systems to close gaps in the available battery of tests.
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Affiliation(s)
- Béla Z Schmidt
- BioTalentum Ltd., Gödöllő, Hungary.,Stem Cell Biology and Embryology Unit, Department of Development and Regeneration, Stem Cell Institute Leuven, KU Leuven, Leuven, Belgium
| | - Martin Lehmann
- BioTalentum Ltd., Gödöllő, Hungary.,Institute of Neurophysiology and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Simon Gutbier
- Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Constance, Germany
| | - Erastus Nembo
- BioTalentum Ltd., Gödöllő, Hungary.,Institute of Neurophysiology and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Sabrina Noel
- Louvain Centre for Toxicology and Applied Pharmacology, Université Catholique de Louvain, Brussels, Belgium
| | - Lena Smirnova
- Center for Alternatives to Animal Testing, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Anna Forsby
- Swedish Toxicology Research Center (Swetox), Södertälje, Sweden.,Department of Neurochemistry, Stockholm University, Stockholm, Sweden
| | - Jürgen Hescheler
- Institute of Neurophysiology and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
| | - Hasan X Avci
- BioTalentum Ltd., Gödöllő, Hungary.,Department of Medical Chemistry, University of Szeged, Szeged, Hungary
| | - Thomas Hartung
- Center for Alternatives to Animal Testing, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Marcel Leist
- Doerenkamp-Zbinden Chair for In Vitro Toxicology and Biomedicine, University of Konstanz, Constance, Germany
| | | | - András Dinnyés
- BioTalentum Ltd., Gödöllő, Hungary. .,Molecular Animal Biotechnology Laboratory, Szent István University, Gödöllő, 2100, Hungary.
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36
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Aschner M, Ceccatelli S, Daneshian M, Fritsche E, Hasiwa N, Hartung T, Hogberg HT, Leist M, Li A, Mundi WR, Padilla S, Piersma AH, Bal-Price A, Seiler A, Westerink RH, Zimmer B, Lein PJ. Reference compounds for alternative test methods to indicate developmental neurotoxicity (DNT) potential of chemicals: example lists and criteria for their selection and use. ALTEX-ALTERNATIVES TO ANIMAL EXPERIMENTATION 2016; 34:49-74. [PMID: 27452664 PMCID: PMC5250586 DOI: 10.14573/altex.1604201] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 07/09/2016] [Indexed: 11/23/2022]
Abstract
There is a paucity of information concerning the developmental neurotoxicity (DNT) hazard posed by industrial and environmental chemicals. New testing approaches will most likely be based on batteries of alternative and complementary (non-animal) tests. As DNT is assumed to result from the modulation of fundamental neurodevelopmental processes (such as neuronal differentiation, precursor cell migration or neuronal network formation) by chemicals, the first generation of alternative DNT tests target these processes. The advantage of such types of assays is that they capture toxicants with multiple targets and modes-of-action. Moreover, the processes modelled by the assays can be linked to toxicity endophenotypes, i.e. alterations in neural connectivity that form the basis for neurofunctional deficits in man. The authors of this review convened in a workshop to define criteria for the selection of positive/negative controls, to prepare recommendations on their use, and to initiate the setup of a directory of reference chemicals. For initial technical optimization of tests, a set of >50 endpoint-specific control compounds was identified. For further test development, an additional “test” set of 33 chemicals considered to act directly as bona fide DNT toxicants is proposed, and each chemical is annotated to the extent it fulfills these criteria. A tabular compilation of the original literature used to select the test set chemicals provides information on statistical procedures, and toxic/non-toxic doses (both for pups and dams). Suggestions are provided on how to use the >100 compounds (including negative controls) compiled here to address specificity, adversity and use of alternative test systems.
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Affiliation(s)
| | | | - Mardas Daneshian
- Center for Alternatives to Animal Testing-Europe (CAAT-Europe), University of Konstanz, Germany
| | - Ellen Fritsche
- Leibniz Research Institute for Environmental Medicine (IUF), Düsseldorf, Germany
| | - Nina Hasiwa
- Center for Alternatives to Animal Testing-Europe (CAAT-Europe), University of Konstanz, Germany
| | - Thomas Hartung
- Center for Alternatives to Animal Testing-Europe (CAAT-Europe), University of Konstanz, Germany.,Center for Alternatives to Animal Testing (CAAT), The Johns Hopkins University, Baltimore, MD, USA
| | - Helena T Hogberg
- Center for Alternatives to Animal Testing (CAAT), The Johns Hopkins University, Baltimore, MD, USA
| | - Marcel Leist
- Center for Alternatives to Animal Testing-Europe (CAAT-Europe), University of Konstanz, Germany.,In vitro Toxicology and Biomedicine, Dept inaugurated by the Doerenkamp-Zbinden Foundation at the University of Konstanz, Konstanz, Germany.,Konstanz Research School Chemical Biology (KoRS-CB), Konstanz University
| | - Abby Li
- Exponent Inc.,San Francisco, USA
| | - William R Mundi
- United States Environmental Protection Agency (USEPA), NHEERL, Research Triangle Park, NC, USA
| | - Stephanie Padilla
- United States Environmental Protection Agency (USEPA), NHEERL, Research Triangle Park, NC, USA
| | - Aldert H Piersma
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.,Institute for Risk Assessment Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Anna Bal-Price
- European Commission Joint Research Centre, Institute for Health and Consumer Protection, Ispra, Italy
| | - Andrea Seiler
- Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Remco H Westerink
- Neurotoxicology Research Group, Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, The Netherlands
| | | | - Pamela J Lein
- Center for Research on Occupational and Environmental Toxicology, Oregon Health & Science University, Portland, USA.,Department of Molecular Biosciences, University of California, Davis, USA
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Daneshian M, Kamp H, Hengstler J, Leist M, van de Water B. Highlight report: Launch of a large integrated European in vitro toxicology project: EU-ToxRisk. Arch Toxicol 2016; 90:1021-4. [PMID: 27017488 PMCID: PMC4830874 DOI: 10.1007/s00204-016-1698-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 03/21/2016] [Indexed: 11/24/2022]
Abstract
The integrated European project, EU-ToxRisk, proudly sees itself as “flagship” exploring new alternative-to-animal approaches to chemical safety evaluation. It promotes mechanism-based toxicity testing and risk assessment according to the principles laid down for toxicology for the twenty-first century. The project was officially launched in January 2016 with a kickoff meeting in Egmond aan Zee, the Netherlands. Over 100 scientists representing academia and industry as well as regulatory authorities attended the inaugural meeting. The project will integrate advances in in vitro and in silico toxicology, read-across methods, and adverse outcome pathways. EU-ToxRisk will continue to make use of the case study strategy deployed in SEURAT-1, a FP7 initiative ended in December 2015. Even though the development of new non-animal methods is one target of EU-ToxRisk, the project puts special emphasis on their acceptance and implementation in regulatory contexts. This €30 million Horizon 2020 project involves 38 European partners and one from the USA. EU-ToxRisk aims at the “development of a new way of risk assessment.”
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Affiliation(s)
- Mardas Daneshian
- Center for Alternatives to Animal Testing - Europe, University of Konstanz, Konstanz, Germany
| | | | - Jan Hengstler
- Leibniz Research Centre for Working Environment and Human Factors, TU Dortmund, Dortmund, Germany
| | - Marcel Leist
- Center for Alternatives to Animal Testing - Europe, University of Konstanz, Konstanz, Germany. .,Department of In Vitro Toxicology and Biomedicine, University of Konstanz, Konstanz, Germany.
| | - Bob van de Water
- Division of Toxicology, Leiden Academic Center for Drug Research, Leiden University, Leiden, The Netherlands
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