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Jiang Z, Li J, Huang G, Yan L, Ma J. Common carp sperm chromatin as an economical and effective remover for benzo( a)pyrene from pollutants. Heliyon 2024; 10:e33137. [PMID: 39022033 PMCID: PMC11252741 DOI: 10.1016/j.heliyon.2024.e33137] [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] [Received: 01/10/2024] [Revised: 06/13/2024] [Accepted: 06/14/2024] [Indexed: 07/20/2024] Open
Abstract
Benzo (a) pyrene is a highly carcinogenic polycyclic aromatic compound, difficult to be degraded, widely present in the environment. However, there is currently no cost-effective and efficient method for removing benzo (a) pyrene. In this study, a feasible method was introduced to cheaply and efficiently adsorb benzo(a)pyrene using chromatin. Scanning electron microscopy analysis showed that the chromatin had a filamentary fiber structure. Fourier transform infrared (FTIR) spectroscopy showed that benzo(a)pyrene formed a bond with the chromatin. Effective binding was confirmed using fluorescence microscopy. Influence factors exploration experiments indicated that the amount of benzo(a)pyrene adsorbed by chromatin was 0.16 mg g-1. The adsorption process of BaP by chromatin is consistent with a pseudo-second-order kinetics model of adsorption. The adsorption isotherm model is consistent with the langmuir isotherm model.This study suggests that chromatin can be utilized as a ordinary and high efficiency adsorbent for removing benzo(a)pyrene and can be utilized in further studies.
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Affiliation(s)
- Zhikang Jiang
- School of Biological and Chemical Engineering, Guangxi University of Science and Technology, Wenchang Road 2, Liuzhou, 545006, Guangxi, China
| | - Junsheng Li
- School of Biological and Chemical Engineering, Guangxi University of Science and Technology, Wenchang Road 2, Liuzhou, 545006, Guangxi, China
| | - Guoxia Huang
- School of Biological and Chemical Engineering, Guangxi University of Science and Technology, Wenchang Road 2, Liuzhou, 545006, Guangxi, China
| | - Liujuan Yan
- School of Biological and Chemical Engineering, Guangxi University of Science and Technology, Wenchang Road 2, Liuzhou, 545006, Guangxi, China
| | - Ji Ma
- School of Biological and Chemical Engineering, Guangxi University of Science and Technology, Wenchang Road 2, Liuzhou, 545006, Guangxi, China
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2
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Nicol B, Vandenbossche-Goddard E, Thorpe C, Newman R, Patel H, Yates D. A workflow to practically apply true dose considerations to in vitro testing for next generation risk assessment. Toxicology 2024; 505:153826. [PMID: 38719068 DOI: 10.1016/j.tox.2024.153826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/22/2024] [Accepted: 05/01/2024] [Indexed: 05/14/2024]
Abstract
With the move away from safety testing assessment based on data generated in experimental animals the concept of Next Generation Risk Assessment (NGRA) has arisen which instead uses data from in silico and in vitro models. A key uncertainty in risk assessment is the actual dose of test chemical at the target site, and therefore surrogate dose metrics, such as nominal concentration in test media are used to describe in vitro effect (or no-effect) doses. The reliability and accuracy of the risk assessment therefore depends largely on our ability to understand and characterise the relationship between the dose metrics used and the actual biologically effective dose at the target site. The objective of this publication is to use 40 case study chemicals to illustrate how in vitro dose considerations can be applied to characterise the "true dose" and build confidence in the understanding of the biologically effective dose in in vitro test systems for the determination e.g. points of departure (PoDs) for NGRA. We propose a workflow that can be applied to assess whether the nominal test concentration can be considered a conservative dose metric for use in NGRA. The workflow examines the implications of volatility, stability, hydrophobicity, binding to plastic and serum, solubility, and the potential use of in silico models for some of these parameters. For the majority of the case study chemicals we found that the use of nominal concentrations in risk assessment would result in conservative decision making. However, for serval chemicals a potential for underestimation of the risk in humans in vivo based on in vitro nominal effect concentrations was identified, and approaches for refinement by characterisation of the actual effect concentration are proposed.
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Affiliation(s)
- Beate Nicol
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedford, Bedfordshire MK44 1LQ, UK
| | - Evita Vandenbossche-Goddard
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedford, Bedfordshire MK44 1LQ, UK.
| | - Charlotte Thorpe
- Unilever Safety and Environmental Assurance Centre, Colworth Science Park, Sharnbrook, Bedford, Bedfordshire MK44 1LQ, UK
| | | | - Hiral Patel
- Charles River Laboratories, Cambridgeshire CB10 1XL, UK
| | - Dawn Yates
- Charles River Laboratories, Cambridgeshire CB10 1XL, UK
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3
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Miller-Holt J, Behrsing H, Crooks I, Curren R, Demir K, Gafner J, Gillman G, Hollings M, Leverette R, Oldham M, Simms L, Stankowski LF, Thorne D, Wieczorek R, Moore MM. Key challenges for in vitro testing of tobacco products for regulatory applications: Recommendations for dosimetry. Drug Test Anal 2023; 15:1175-1188. [PMID: 35830202 PMCID: PMC9897201 DOI: 10.1002/dta.3344] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/02/2022] [Accepted: 07/05/2022] [Indexed: 02/05/2023]
Abstract
The Institute for In Vitro Sciences (IIVS) is sponsoring a series of workshops to develop recommendations for optimal scientific and technical approaches for conducting in vitro assays to assess potential toxicity within and across tobacco and various next-generation products (NGPs) including heated tobacco products (HTPs) and electronic nicotine delivery systems (ENDSs). This publication was developed by a working group of the workshop members in conjunction with the sixth workshop in that series entitled "Dosimetry for conducting in vitro evaluations" and focuses on aerosol dosimetry for aerosol exposure to combustible cigarettes, HTP, and ENDS aerosolized tobacco products and summarizes the key challenges as well as documenting areas for future research.
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Affiliation(s)
| | - Holger Behrsing
- Institute for In Vitro Sciences, Gaithersburg, Maryland, USA
| | - Ian Crooks
- Consumer Product Safety, British American Tobacco, Southampton, UK
| | - Rodger Curren
- Institute for In Vitro Sciences, Gaithersburg, Maryland, USA
| | - Kubilay Demir
- Regulatory Science, JUUL Labs Inc., 1000 F Street NW, Washington D.C. 20004, USA
| | - Jeremie Gafner
- Scientific & Regulatory Affairs, JT International SA, Geneva, Switzerland
| | - Gene Gillman
- Regulatory Science, JUUL Labs Inc., 1000 F Street NW, Washington D.C. 20004, USA
| | - Michael Hollings
- Genetic Toxicology, Labcorp Early Development Laboratories Ltd., Harrogate, UK
| | - Robert Leverette
- Scientific & Regulatory Affairs, RAI Services Company, Winston-Salem, North Carolina, USA
| | - Michael Oldham
- Regulatory Science, JUUL Labs Inc., 1000 F Street NW, Washington D.C. 20004, USA
| | - Liam Simms
- Group Science and Regulatory Affairs, Imperial Brands, Bristol, UK
| | - Leon F. Stankowski
- Genetic and In Vitro Toxicology, Charles River Laboratories–Skokie, Skokie, Illinois, USA
| | - David Thorne
- Consumer Product Safety, British American Tobacco, Southampton, UK
| | - Roman Wieczorek
- Group Science and Regulatory Affairs, Reemtsma Cigarettenfabriken GmbH, an Imperial Brands PLC Company, Hamburg, Germany
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4
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Cordova AC, Ford LC, Valdiviezo A, Roman-Hubers AT, McDonald TJ, Chiu WA, Rusyn I. Dosing Methods to Enable Cell-Based In Vitro Testing of Complex Substances: A Case Study with a PAH Mixture. TOXICS 2022; 11:19. [PMID: 36668745 PMCID: PMC9866728 DOI: 10.3390/toxics11010019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 12/21/2022] [Accepted: 12/24/2022] [Indexed: 06/17/2023]
Abstract
Cell-based testing of multi-constituent substances and mixtures for their potential adverse health effects is difficult due to their complex composition and physical-chemical characteristics. Various extraction methods are typically used to enable studies in vitro; however, a limited number of solvents are biocompatible with in vitro studies and the extracts may not fully represent the original test article's composition. While the methods for dosing with "difficult-to-test" substances in aquatic toxicity studies are well defined and widely used, they are largely unsuited for small-volume (100 microliters or less) in vitro studies with mammalian cells. Therefore, we aimed to evaluate suitability of various scaled-down dosing methods for high-throughput in vitro testing by using a mixture of polycyclic aromatic hydrocarbons (PAH). Specifically, we compared passive dosing via silicone micro-O-rings, cell culture media-accommodated fraction, and traditional solvent (dimethyl sulfoxide) extraction procedures. Gas chromatography-tandem mass spectrometry (GC-MS/MS) was used to evaluate kinetics of PAH absorption to micro-O-rings, as well as recovery of PAH and the extent of protein binding in cell culture media with and without cells for each dosing method. Bioavailability of the mixture from different dosing methods was also evaluated by characterizing in vitro cytotoxicity of the PAH mixture using EA.hy926 and HepG2 human cell lines. Of the tested dosing methods, media accommodated fraction (MAF) was determined to be the most appropriate method for cell-based studies of PAH-containing complex substances and mixtures. This conclusion is based on the observation that the highest fraction of the starting materials can be delivered using media accommodated fraction approach into cell culture media and thus enable concentration-response in vitro testing.
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Affiliation(s)
- Alexandra C. Cordova
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Lucie C. Ford
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Alan Valdiviezo
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Alina T. Roman-Hubers
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Thomas J. McDonald
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Departments of Environmental and Occupational Health, Texas A&M University, College Station, TX 77843, USA
| | - Weihsueh A. Chiu
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - Ivan Rusyn
- Interdisciplinary Faculty of Toxicology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
- Department of Veterinary Physiology and Pharmacology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
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5
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Chapman F, Sticken ET, Wieczorek R, Pour SJ, Dethloff O, Budde J, Rudd K, Mason E, Czekala L, Yu F, Simms L, Nahde T, O'Connell G, Stevenson M. Multiple endpoint in vitro toxicity assessment of a prototype heated tobacco product indicates substantially reduced effects compared to those of combustible cigarette. Toxicol In Vitro 2022; 86:105510. [DOI: 10.1016/j.tiv.2022.105510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/22/2022] [Accepted: 10/31/2022] [Indexed: 11/13/2022]
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6
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Bao Z, Wang J, He M, Zhang P, Shan L, Yao Y, Wang Q, Zheng L, Ge H, Zhou J. Benzo[a]pyrene inhibits myoblast differentiation through downregulating the Hsp70-K2-p38MAPK complex. Toxicol In Vitro 2022; 82:105356. [PMID: 35427736 DOI: 10.1016/j.tiv.2022.105356] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 03/11/2022] [Accepted: 04/07/2022] [Indexed: 10/18/2022]
Abstract
Cigarette smoking causes skeletal muscle dysfunction and worse prognosis for patients with diverse systemic diseases. Benzo[a]pyrene (BaP), one major constituent that is inhaled during smoking, is particularly known for its ability to impair neurodevelopment, impede reproductivity, or reduce birth weight. Here, we found that BaP exposure led to the inhibition of C2C12 myoblasts differentiation in a dose-dependent manner and reduced the expression of both early and late myogenic differentiation markers. BaP exposure significantly decreased the expression of p38 mitogen-activated protein kinase (p38MAPK), but not AKT, which are both critical during myogenic differentiation. Mechanistically, BaP deregulated the expression levels of MAPK-activated protein kinase 2 (MK2) and heat shock protein 70 (Hsp70), both of which stabilize p38MAPK. Interestingly, treatment of proteasome inhibitor MG132 was able to reverse BaP-induced degradation of Hsp70/ MK2 and p38MAPK in myoblasts, implying BaP-mediated p38MAPK degradation is proteasome-dependent. Overexpression of p38MAPK also rescued the defective differentiation phenotype of C2C12 induced by BaP. Taken together, we suggest that BaP exposure induces MK2/Hsp70/p38MAPK complex degradation in C2C12 myoblasts and impairs myogenic differentiation by proteasomal-dependent mechanisms. As application of the proteasome inhibitor MG132 or overexpression of p38MAPK could reverse impaired differentiation of myoblasts induced by BaP, this may suggest potential related strategies for preventing tobacco-related skeletal muscle diseases or for respiratory rehabilitation.
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Affiliation(s)
- Zhang Bao
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Jianfeng Wang
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Mingjie He
- Department of Biochemistry and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Laboratory for Tissue Engineering and Regenerative Medicine, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Pei Zhang
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Lu Shan
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Yinan Yao
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Qing Wang
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Liling Zheng
- Department of Biochemistry and Department of General Intensive Care Unit of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Laboratory for Tissue Engineering and Regenerative Medicine, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Huiqing Ge
- Department of Respiratory Care, Regional Medical Center for the National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, China.
| | - Jianying Zhou
- Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China.
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7
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Chapman KE, Wilde EC, Chapman FM, Verma JR, Shah UK, Stannard LM, Seager AL, Tonkin JA, Brown MR, Doherty AT, Johnson GE, Doak SH, Jenkins GJS. Multiple-endpoint in vitro carcinogenicity test in human cell line TK6 distinguishes carcinogens from non-carcinogens and highlights mechanisms of action. Arch Toxicol 2021; 95:321-336. [PMID: 32910239 PMCID: PMC7811515 DOI: 10.1007/s00204-020-02902-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 09/02/2020] [Indexed: 12/12/2022]
Abstract
Current in vitro genotoxicity tests can produce misleading positive results, indicating an inability to effectively predict a compound's subsequent carcinogenic potential in vivo. Such oversensitivity can incur unnecessary in vivo tests to further investigate positive in vitro results, supporting the need to improve in vitro tests to better inform risk assessment. It is increasingly acknowledged that more informative in vitro tests using multiple endpoints may support the correct identification of carcinogenic potential. The present study, therefore, employed a holistic, multiple-endpoint approach using low doses of selected carcinogens and non-carcinogens (0.001-770 µM) to assess whether these chemicals caused perturbations in molecular and cellular endpoints relating to the Hallmarks of Cancer. Endpoints included micronucleus induction, alterations in gene expression, cell cycle dynamics, cell morphology and bioenergetics in the human lymphoblastoid cell line TK6. Carcinogens ochratoxin A and oestradiol produced greater Integrated Signature of Carcinogenicity scores for the combined endpoints than the "misleading" in vitro positive compounds, quercetin, 2,4-dichlorophenol and quinacrine dihydrochloride and toxic non-carcinogens, caffeine, cycloheximide and phenformin HCl. This study provides compelling evidence that carcinogens can successfully be distinguished from non-carcinogens using a holistic in vitro test system. Avoidance of misleading in vitro outcomes could lead to the reduction and replacement of animals in carcinogenicity testing.
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Affiliation(s)
- Katherine E Chapman
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK.
| | - Eleanor C Wilde
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Fiona M Chapman
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Jatin R Verma
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Ume-Kulsoom Shah
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Leanne M Stannard
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Anna L Seager
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - James A Tonkin
- College of Engineering, Swansea University, Bay Campus, Swansea, SA1 8EN, UK
| | - M Rowan Brown
- College of Engineering, Swansea University, Bay Campus, Swansea, SA1 8EN, UK
| | - Ann T Doherty
- Discovery Safety, AstraZeneca, DSM, Darwin Building, Cambridge Science Park, Milton Road, Cambridge, CB4 0WG, UK
| | - George E Johnson
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Shareen H Doak
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
| | - Gareth J S Jenkins
- In Vitro Toxicology Group, Institute of Life Science 1, Swansea University Medical School, Swansea University, Singleton Campus, Swansea, SA2 8PP, UK
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8
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Shah UK, Verma JR, Chapman KE, Wilde EC, Tonkin JA, Brown MR, Johnson GE, Doak SH, Jenkins GJ. Detection of urethane-induced genotoxicity in vitro using metabolically competent human 2D and 3D spheroid culture models. Mutagenesis 2020; 35:445-452. [PMID: 33219664 DOI: 10.1093/mutage/geaa029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 10/22/2020] [Indexed: 11/14/2022] Open
Abstract
In vitro genotoxicity studies are a quick and high throughput approach to assess the genotoxic potential of chemicals; however, the reliability of these tests and their relevance to in vivo effects depends on the choice of representative cell line and optimisation of assay conditions. For chemicals like urethane that require specific metabolic activation to cause genotoxicity, it is important that in vitro tests are conducted using cell lines exhibiting the activity and induction of CYP450 enzymes, including CYP2E1 enzyme that is important in the metabolism of urethane, at a concentration representing actual or perceived chemical exposure. We compared 2D MCL-5 cells and HepG2 cells with 3D HepG2 hanging drop spheroids to determine the genotoxicity of urethane using the micronucleus assay. Our 2D studies with MCL-5 did not show any statistically significant genotoxicity [99% relative population doubling (RPD)] compared to controls for concentrations and time point tested in vitro. HepG2 cells grown as 2D indicated that exposure to urethane of up to 30 mM for 23 h did not cause any genotoxic effect (102% RPD) but, at higher concentrations, genotoxicity was produced with only 89-85% RPD. Furthermore, an exposure of 20-50 mM for 23 h using 3D hanging drop spheroid assays revealed a higher MN frequency, thus exhibiting in vitro genotoxicity of urethane in metabolically active cell models. In comparison with previous studies, this study indicated that urethane genotoxicity is dose, sensitivity of cell model (2D vs. 3D) and exposure dependent.
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Affiliation(s)
- Ume-Kulsoom Shah
- In Vitro Toxicology Group, Institute of Life Science 1, Singleton Campus, Swansea University Medical School, Swansea University, Swansea, UK
| | - Jatin R Verma
- Associate Scientist, Genetic & Molecular Toxicology, Covance Laboratories Limited, Otley Road, Harrogate, North Yorkshire, UK
| | - Katherine E Chapman
- In Vitro Toxicology Group, Institute of Life Science 1, Singleton Campus, Swansea University Medical School, Swansea University, Swansea, UK
| | - Eleanor C Wilde
- In Vitro Toxicology Group, Institute of Life Science 1, Singleton Campus, Swansea University Medical School, Swansea University, Swansea, UK
| | - James A Tonkin
- College of Engineering, Bay Campus, Swansea University, Swansea, UK
| | - Martyn R Brown
- College of Engineering, Bay Campus, Swansea University, Swansea, UK
| | - George E Johnson
- In Vitro Toxicology Group, Institute of Life Science 1, Singleton Campus, Swansea University Medical School, Swansea University, Swansea, UK
| | - Shareen H Doak
- In Vitro Toxicology Group, Institute of Life Science 1, Singleton Campus, Swansea University Medical School, Swansea University, Swansea, UK
| | - Gareth J Jenkins
- In Vitro Toxicology Group, Institute of Life Science 1, Singleton Campus, Swansea University Medical School, Swansea University, Swansea, UK
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9
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Xiong Y, Li J, Huang G, Yan L, Ma J. Interacting mechanism of benzo(a)pyrene with free DNA in vitro. Int J Biol Macromol 2020; 167:854-861. [PMID: 33181208 DOI: 10.1016/j.ijbiomac.2020.11.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/28/2020] [Accepted: 11/06/2020] [Indexed: 12/25/2022]
Abstract
Polycyclic aromatic hydrocarbons are environmental pollutants with strong carcinogenicity, indirect teratogenicity, and mutagenicity. This study explored the interaction mechanism of benzo(a)pyrene with free DNA in vitro by using various analytical methods. UV-vis spectra showed that benzo(a)pyrene and DNA formed a new benzo(a)pyrene-DNA complex. The thermal melting temperature of DNA increased by 12.7 °C, showing that the intercalation of benzo(a)pyrene into DNA could promote the stability of the DNA double helix structure. The intercalation of benzo(a)pyrene with DNA in vitro was further confirmed by fluorescence microscopy with magnetic beads. Fluorescence spectra showed that the interaction between DNA and benzo(a)pyrene decreased the fluorescence intensity of benzo(a)pyrene, and the maximum quenching rate was 27.89%. The quenching mode of benzo(a)pyrene was static quenching. Thermodynamic data showed that the main driving forces were van der Waals forces and hydrogen bonds, and the reaction was spontaneous. The results of this study provided a novel insight for the establishment of polycyclic aromatic hydrocarbon capture and elimination through polycyclic aromatic hydrocarbon-DNA intercalation.
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Affiliation(s)
- Yining Xiong
- Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China
| | - Junsheng Li
- Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China.
| | - Guoxia Huang
- Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China
| | - Liujuan Yan
- Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China
| | - Ji Ma
- Guangxi Key Laboratory of Green Processing of Sugar Resources, Guangxi University of Science and Technology, Donghuan Road 268, Liuzhou 545006, Guangxi, PR China
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