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Huang T, Jones CG, Chung JH, Chen C. Microfibrous Extracellular Matrix Changes the Liver Hepatocyte Energy Metabolism via Integrins. ACS Biomater Sci Eng 2020; 6:5849-5856. [PMID: 33320566 DOI: 10.1021/acsbiomaterials.0c01311] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cell line-based liver models are critical tools for liver-related studies. However, the conventional monolayer culture of hepatocytes, the most widely used in vitro model, does not have the extracellular matrix (ECM), which contributes to the three-dimensional (3D) arrangement of the hepatocytes in the liver. As a result, the metabolic properties of the hepatocytes in the monolayer tissue culture may not accurately reflect those of the hepatocytes in the liver. Here, we developed a modular platform for 3D hepatocyte cultures on fibrous ECMs produced by electrospinning, a technique that can turn a polymer solution to the micro/nanofibers and has been widely used to produce scaffolds for 3D cell cultures. Metabolomics quantitation by liquid chromatography-mass spectrometry (LC-MS) indicated that Huh7 hepatocytes grown in microfibers electrospun from silk fibroin exhibited reduced glycolysis and tricarboxylic acid (TCA) cycle, as compared to the cells cultured as a monolayer. Further mechanistic studies suggested that integrins were correlated to the ECM's effects. This is the first time to report how an ECM scaffold could affect the fundamental metabolism of the hepatocytes via integrins.
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Affiliation(s)
- Tianjiao Huang
- Laboratory of Obesity and Aging Research, Cardiovascular Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Curtis G Jones
- The Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, Maryland 21250, United States
| | - Jay H Chung
- Laboratory of Obesity and Aging Research, Cardiovascular Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Chengpeng Chen
- The Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, Maryland 21250, United States
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2
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Bach PH, Vickers AE, Fisher R, Baumann A, Brittebo E, Carlile DJ, Koster HJ, Lake BG, Salmon F, Sawyer TW, Skibinski G. The Use of Tissue Slices for Pharmacotoxicology Studies. Altern Lab Anim 2020. [DOI: 10.1177/026119299602400605] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Peter H. Bach
- Interdisciplinary Research Centre for Cell Modulation Studies, Faculty of Science and Health, University of East London, Romford Road, London E15 4LZ, UK
| | | | - Robyn Fisher
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA
| | - Andreas Baumann
- Institut für Pharmakokinetik, Schering Aktiengesellschaft, 13342 Berlin, Germany
| | - Eva Brittebo
- Department of Pharmacology and Toxicology, SLU Biomedical Centre, 751 23 Uppsala, Sweden
| | - David J. Carlile
- Department of Pharmacy, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Henk J. Koster
- Solvay Duphar, C.J. van Houlenlaan 36, 1380 DA Weesp, The Netherlands
| | - Brian G. Lake
- BIBRA International, Woodmansterne Road, Carshalton, Surrey SM5 4DS, UK
| | - Florence Salmon
- Crop Protection Animal Metabolism and Residue Chemistry, BASF Aktiengesellschaft, 67114 Limburgerhof, Germany
| | - Thomas W. Sawyer
- Medical Countermeasures Section, Defence Research Establishment Suffield, Medicine Hat, Alberta T1A 8K6, Canada
| | - Greg Skibinski
- Department of Surgery, University of Edinburgh Medical School, Teviot Place, Edinburgh EH8 9AG, UK
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3
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Baumann A, Feser W, Cramer P, Kerdar RS, Blode H, Korber J, Kuhnz W. Use of precision cut human liver slices for studying the metabolism and genotoxic potential of xenobiotics by means of the (32)P-postlabelling technique: steps towards method validation using testosterone and 2-aminofluorene. Biomarkers 2013; 4:188-202. [PMID: 23885862 DOI: 10.1080/135475099230868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
In the present study, a new in vitro model combining the short-term incubation of precision-cut human liver slices with DNA-adduct analysis by the (32)P-postlabelling technique is proposed for investigation of the genotoxic potential of xenobiotics. For method validation, the metabolic turnover of testosterone (TES) and the DNA-adduct inducing potential of 2-aminofluorene (2-AF) were used. Precision-cut human liver slices were prepared from a total of 12 human liver samples which were freshly obtained as parts of resectates from liver surgery. The slices were incubated as submersion cultures with TES and 2-AF for up to 6 h in 12-well tissue culture plates at concentrations of 10-50 and 0.06-28 μM, respectively. Slices recovered from the slicing procedure in the 4 °C cold Krebs-Henseleit buffer as indicated by intracellular potassium concentrations which increased for 2 h and then remained stable until the end of the incubation. TES was extensively metabolized by human liver slices with a similar metabolite pattern as observed in vivo. Almost 90% of the metabolites were conjugates. Major phase-I metabolites were androstendione, 6β-OH-androstendione, 6β-OH-TES, and 15β-OHTES. After incubation with 2-AF, substance related DNA-adducts were detected which increased dose-dependently from 12 to 1146 adducts per 10(9) nucleotides. The adduct pattern consisted of one major adduct spot, A, representing 80-90% of the total adduct level and up to four minor adduct spots, B-E. In summary, the present data demonstrate that precision-cut liver slices are a valuable alternative in vitro system for DNA-adduct determination to screen chemicals for potential genotoxicity in humans.
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Affiliation(s)
- A Baumann
- Research Laboratories, Schering AG, 13342 Berlin, Germany
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4
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Soldatow VY, Lecluyse EL, Griffith LG, Rusyn I. In vitro models for liver toxicity testing. Toxicol Res (Camb) 2012; 2:23-39. [PMID: 23495363 DOI: 10.1039/c2tx20051a] [Citation(s) in RCA: 320] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Over the years, various liver-derived in vitro model systems have been developed to enable investigation of the potential adverse effects of chemicals and drugs. Liver tissue slices, isolated microsomes, perfused liver, immortalized cell lines, and primary hepatocytes have been used extensively. Immortalized cell lines and primary isolated liver cells are currently most widely used in vitro models for liver toxicity testing. Limited throughput, loss of viability, and decreases in liver-specific functionality and gene expression are common shortcomings of these models. Recent developments in the field of in vitro hepatotoxicity include three-dimensional tissue constructs and bioartificial livers, co-cultures of various cell types with hepatocytes, and differentiation of stem cells into hepatic lineage-like cells. In an attempt to provide a more physiological environment for cultured liver cells, some of the novel cell culture systems incorporate fluid flow, micro-circulation, and other forms of organotypic microenvironments. Co-cultures aim to preserve liver-specific morphology and functionality beyond those provided by cultures of pure parenchymal cells. Stem cells, both embryonic- and adult tissue-derived, may provide a limitless supply of hepatocytes from multiple individuals to improve reproducibility and enable testing of the individual-specific toxicity. This review describes various traditional and novel in vitro liver models and provides a perspective on the challenges and opportunities afforded by each individual test system.
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Affiliation(s)
- Valerie Y Soldatow
- Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC 27599, USA
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5
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Lake BG, Price RJ. Evaluation of the metabolism and hepatotoxicity of xenobiotics utilizing precision-cut slices. Xenobiotica 2012; 43:41-53. [DOI: 10.3109/00498254.2012.734643] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Olinga P, Meijer DK, Slooff MJ, Groothuis GM. Liver slices in in vitro pharmacotoxicology with special reference to the use of human liver tissue. Toxicol In Vitro 2012; 12:77-100. [PMID: 20654390 DOI: 10.1016/s0887-2333(97)00097-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/25/1997] [Indexed: 11/18/2022]
Abstract
In the early years of research in in vitro pharmacotoxicology liver slices have been used. After a decline in the application of slices in favour of the use of isolated hepatocytes and the isolated perfused liver preparation, the development of the Krumdieck slicer in the 1980s led to a ;comeback' of the technique. This review will focus on the use of human liver, with special reference to the comparison of slices with isolated hepatocytes in in vitro pharmacotoxicology. In addition, an overview on the predictive value of these in vitro systems for drug disposition and toxicity in vivo will be given. Preservation techniques for liver slices and hepatocytes will also be discussed. These techniques ensure an efficient utilization of the scarce human material. For long-term storage of liver slices and hepatocytes, cryopreservation seems most promising. However, cryopreservation is still in its infancy, and reports mainly deal with drug metabolism studies after cryopreservation. Drug toxicity, metabolism and transport data determined in slices and isolated hepatocytes, from both human and animal liver showed good correlation with the corresponding parameters measured in vivo. Therefore, the results obtained in such studies may give rise to more in-depth research on the mechanisms of pharmactoxicology in the human liver.
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Affiliation(s)
- P Olinga
- Division of Hepatobiliary Surgery and Liver Transplantation, Department of Surgery, University Hospital, Hanzeplein 1, 9713 EZ Groningen, The Netherlands
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7
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Ohyama K, Maki S, Sato K, Kato Y. In vitrometabolism of [14C]methoxychlor in rat, mouse, Japanese quail and rainbow trout in precision-cut liver slices. Xenobiotica 2008; 34:741-54. [PMID: 15690762 DOI: 10.1080/00498250400003455] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
1. The in vitro metabolism of [14C]methoxychlor (MXC) has been studied using precision-cut liver slices from the Sprague-Dawley male rat, CD-1 male mouse, WE strain male Japanese quail and juvenile rainbow trout (Oncorhynchus mykiss). The results demonstrated integrated phase I and II metabolism of MXC and species differences in the metabolic profiles were observed. 2. In rat liver slice preparations, MXC was rapidly metabolized to bis-OH-MXC by sequential O-demethylation followed by subsequent O-glucuronidation forming bis-OH-MXC glucuronide. No mono-OH-MXC glucuronide was detected. The doubly conjugated metabolite, bis-OH-MXC 4-O-sulphate 4'-O-glucuronide, was also detected as a rat-specific metabolite. 3. Formation of mono-OH-MXC and its glucuronide was the main metabolic pathway in the mouse and Japanese quail. In contrast to the rat, only minor amounts of bis-OH-MXC glucuronide were detected. A reductively dehalogenated metabolite, dechlorinated mono-OH-MXC glucuronide, was observed only in mouse preparations. 4. In rainbow trout, comparative amounts of both mono- and bis-OH-MXC glucuronide were formed as the major metabolites. Unconjugated forms of these metabolites were detected only as minor products. 5. The different metabolic profiles of MXC observed in the four animal species are possibly due to substrate specificity of contributing CYP450 monooxgenase enzyme(s) in different animal species.
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Affiliation(s)
- K Ohyama
- Institute of Environmental Toxicology, Uchi-moriya 4321, Mitsukaido, Ibaraki 303-0043, Japan.
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8
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Plazar J, Hreljac I, Pirih P, Filipic M, Groothuis GMM. Detection of xenobiotic-induced DNA damage by the comet assay applied to human and rat precision-cut liver slices. Toxicol In Vitro 2007; 21:1134-42. [PMID: 17459656 DOI: 10.1016/j.tiv.2007.02.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2006] [Revised: 02/21/2007] [Accepted: 02/27/2007] [Indexed: 11/18/2022]
Abstract
The comet assay is a simple and sensitive method for measuring DNA damage at the level of individual cells and is extensively used in genotoxicity studies. It is commonly applied to cultured cells. The aim of this study was to apply the comet assay for use in fresh liver tissue, where metabolic activity, all cell types and tissue architecture are preserved. The response of liver slices to genotoxic agents was tested with the reactive oxygen species generating tert-butyl hydroperoxide (tBOOH, 0.1-2 mM), [corrected] and the pro-carcinogens 2-amino-3-methylimidazo[4,5-f]quinoline (IQ, 0.5-2 mM) and benzo(a)pyrene (BaP, 10-100 microM). Dose-dependent DNA damage was observed and compared to HepG2 cells. At non-cytotoxic concentrations of carcinogens, human liver slices were more sensitive to tBOOH than rat liver slices, while no significant difference was found for BaP and IQ. Human liver slices were more sensitive to IQ than HepG2 cells, equally sensitive to BaP and less to tBOOH. Control slices showed low levels of DNA damage, which did not increase during 24 h preservation (0 degrees C) or 48 h culturing (37 degrees C). In conclusion, the comet assay that we applied for measuring DNA damage in precision-cut liver slices is an useful tool to study genotoxic effects induced by various potential genotoxicants, allowing for detection of species differences in susceptibility to carcinogens.
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Affiliation(s)
- Janja Plazar
- Department of Pharmacokinetics and Drug Delivery, University Centre for Pharmacy, University of Groningen, A. Deusinglaan 1, 9713 AV Groningen, The Netherlands.
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9
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Opinion of the Scientific Panel on food additives, flavourings, processing aids and materials in contact with food (AFC) related to Coumarin. EFSA J 2004. [DOI: 10.2903/j.efsa.2004.104] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
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10
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Lake BG, Edwards AJ, Price RJ, Phillips BJ, Renwick AB, Beamand JA, Adams TB. Lack of effect of furfural on unscheduled DNA synthesis in the in vivo rat and mouse hepatocyte DNA repair assays and in precision-cut human liver slices. Food Chem Toxicol 2001; 39:999-1011. [PMID: 11524138 DOI: 10.1016/s0278-6915(01)00050-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The ability of furfural to induce unscheduled DNA synthesis (UDS) in hepatocytes of male and female B6C3F(1) mice and male F344 rats after in vivo administration and in vitro in precision-cut human liver slices has been studied. Preliminary toxicity studies established the maximum tolerated dose (MTD) of furfural to be 320 and 50 mg/kg in the mouse and rat, respectively. Furfural was dosed by gavage at levels of 0 (control), 50, 175 and 320 mg/kg to male and female mice and 0, 5, 16.7 and 50 mg/kg to male rats. Hepatocytes were isolated by liver perfusion either 2-4 h or 12-16 h after treatment, cultured in medium containing [3H]thymidine for 4 h and assessed for UDS by grain counting of autoradiographs. Furfural treatment did not produce any statistically significant increase or any dose-related effects on UDS in mouse and rat hepatocytes either 2-4 h or 12-16 h after dosing. In contrast, UDS was markedly induced in mice and rats 2-4 h after treatment with 20 mg/kg dimethylnitrosamine and 12-16 h after treatment of mice and rats with 200 mg/kg o-aminoazotoluene and 50 mg/kg 2-acetylaminofluorene (2-AAF), respectively. Precision-cut human liver slices from four donors were cultured for 24 h in medium containing [3H]thymidine and 0-10 mM furfural. Small increases in the net grain count (i.e. nuclear grain count less mean cytoplasmic grain count) observed with 2-10 mM furfural were not due to any increase in the nuclear grain count. Rather, it was the result of concentration-dependent decreases in the mean cytoplasmic grain counts and to a lesser extent in nuclear grain counts, due to furfural-induced cytotoxicity. In contrast, marked increases in UDS (both net grain and nuclear grain counts) were observed in human liver slices treated with 0.02 and 0.05 mM 2-AAF, 0.002 and 0.02 mM aflatoxin B(1) and 0.005 and 0.05 mM 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine. This study demonstrates that furfural does not induce UDS in the hepatocytes of male and female B6C3F(1) mice and male F344 rats after oral treatment at doses up to the MTDs. Moreover, human liver slice studies suggest that furfural is also not a genotoxic agent in human liver.
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Affiliation(s)
- B G Lake
- TNO BIBRA International Ltd, Woodmansterne Road, Carshalton, Surrey SM5 4DS, UK.
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11
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Lerche-Langrand C, Toutain HJ. Precision-cut liver slices: characteristics and use for in vitro pharmaco-toxicology. Toxicology 2000; 153:221-53. [PMID: 11090959 DOI: 10.1016/s0300-483x(00)00316-4] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- C Lerche-Langrand
- Drug Safety Evaluation, Aventis Pharma SA, 13 quai Jules Guesde, 94403, Vitry-sur-Seine, France.
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12
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Abstract
The metabolism, toxicity and results of tests for carcinogenicity have been reviewed with respect to the safety for humans of coumarin present in foodstuffs and from fragrance use in cosmetic products. Coumarin is a natural product which exhibits marked species differences in both metabolism and toxicity. The majority of tests for mutagenic and genotoxic potential suggest that coumarin is not a genotoxic agent. The target organs for toxicity and carcinogenicity in the rat and mouse are primarily the liver and lung. Moreover, the dose-response relationships for coumarin-induced toxicity and carcinogenicity are non-linear, with tumour formation only being observed at high doses which are associated with hepatic and pulmonary toxicity. Other species, including the Syrian hamster, are seemingly resistant to coumarin-induced toxicity. There are marked differences in coumarin metabolism between susceptible rodent species and other species including humans. It appears that the 7-hydroxylation pathway of coumarin metabolism, the major pathway in most human subjects but only a minor pathway in the rat and mouse, is a detoxification pathway. In contrast, the major route of coumarin metabolism in the rat and mouse is by a 3,4-epoxidation pathway resulting in the formation of toxic metabolites. The maximum daily human exposure to coumarin from dietary sources for a 60-kg consumer has been estimated to be 0.02 mg/kg/day. From fragrance use in cosmetic products, coumarin exposure has been estimated to be 0.04 mg/kg/day. The total daily human exposure from dietary sources together with fragrance use in cosmetic products is thus 0.06 mg/kg/day. No adverse effects of coumarin have been reported in susceptible species in response to doses which are more than 100 times the maximum human daily intake. The mechanism of coumarin-induced tumour formation in rodents is associated with metabolism-mediated, toxicity and it is concluded that exposure to coumarin from food and/or cosmetic products poses no health risk to humans.
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Affiliation(s)
- B G Lake
- BIBRA International, Carshalton, Surrey, UK
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Lake BG, Beamand JA, Tredger JM, Barton PT, Renwick AB, Price RJ. Inhibition of xenobiotic-induced genotoxicity in cultured precision-cut human and rat liver slices. Mutat Res 1999; 440:91-100. [PMID: 10095132 DOI: 10.1016/s1383-5718(99)00010-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this study precision-cut liver slices have been used to evaluate the effects of the flavone tangeretin, the flavonoid glycoside naringin and the flavanone naringenin (the aglycone derived from naringin) on xenobiotic-induced genotoxicity. Liver slices were cultured for 24 h in medium containing [3H]thymidine and the test compounds and then processed for autoradiographic determination of unscheduled DNA synthesis (UDS). The cooked food mutagen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) markedly induced UDS in cultured human liver slices and both 2-acetylaminofluorene (2-AAF) and aflatoxin B1 (AFB1) induced UDS in cultured rat liver slices. Tangeretin (20 and 50 microM) was found to be a potent inhibitor of 5 and 50 microM PhIP-induced UDS in human liver slices, whereas 20 and 50 microM naringenin was ineffective and naringin only inhibited genotoxicity at a concentration of 1000 microM. In rat liver slices 50 microM tangeretin inhibited 10 and 50 microM 2-AAF-induced UDS, whereas 50 microM naringenin and 100 and 1000 microM naringin were ineffective. None of the three flavonoids examined inhibited 5 microM AFB1-induced UDS in rat liver slices. The inhibition of PhIP- and 2-AAF-induced UDS by tangeretin is probably attributable to the inhibition of the human and rat cytochrome P-450 isoforms which are responsible for the bioactivation of these two genotoxins. Although flavonoids can modulate xenobiotic-induced genotoxicity in human and rat liver slices, any protective effect is dependent on the particular combination of genotoxin and flavonoid examined. These results demonstrate that cultured precision-cut liver slices may be utilised as an in vitro model system to examine the modulation of xenobiotic-induced genotoxicity by flavonoids and other dietary components.
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Affiliation(s)
- B G Lake
- BIBRA International, Woodmansterne Road, Carshalton, Surrey, SM5 4DS, UK
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Beamand JA, Barton PT, Price RJ, Lake BG. Lack of effect of coumarin on unscheduled DNA synthesis in precision-cut human liver slices. Food Chem Toxicol 1998; 36:647-53. [PMID: 9734715 DOI: 10.1016/s0278-6915(98)00025-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
In this study the effect of coumarin on unscheduled DNA synthesis (UDS) in precision-cut human liver slices has been examined. Liver slices from tissue samples from four donors were cultured for 24 hr in medium containing [3H]thymidine and 0-5.0 mM coumarin using a dynamic organ culture system and processed for autoradiographic evaluation of UDS. As positive controls liver slices were also cultured with three known genotoxic agents, namely 0.02 and 0.05 mM 2-acetylaminofluorene (2-AAF), 0.002 and 0.02 mM aflatoxin B1 (AFB1) and 0.005 and 0.05 mM 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP). UDS was quantified as the net grain count in centrilobular hepatocytes and as the percentage of centrilobular hepatocyte nuclei with more than five net grains. Compared with control liver slice cultures, treatment with 0.05-5.0 mM coumarin had no effect on UDS. In contrast, treatment with 0.02 and 0.05 mM 2-AAF, 0.002 and 0.02 mM AFB1 and 0.005 and 0.05 mM PhIP produced significant increases in the net grain counts of centrilobular hepatocytes. The greatest induction of UDS was observed in liver slices treated with 0.05 mM PhIP. Treatment with 2-AAF, AFB1 and PhIP also produced significant increases in the number of centrilobular hepatocyte nuclei with more than five net grains. At the concentrations examined neither coumarin. 2-AAF, AFB1 nor PhIP had any significant effect on replicative DNA synthesis in 24 hr cultured human liver slices. These results demonstrate that coumarin does not induce UDS in cultured human liver slices. However, all three positive control compounds produced marked significant increases in UDS, thus confirming the functional viability of the human liver slice preparations used in this study. The results of this study suggest that coumarin is not a genotoxic agent in human liver.
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Feser W, Kerdar R, Baumann A, Körber J, Blode H, Kuhnz W. DNA Adduct Formation of Selected Sex Steroids in Human Liver Slices In Vitro. Toxicol In Vitro 1998; 12:353-64. [DOI: 10.1016/s0887-2333(98)80005-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/1997] [Indexed: 11/28/2022]
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16
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Beamand JA, Barton PT, Tredger JM, Price RJ, Lake BG. Effect of some cooked food mutagens on unscheduled DNA synthesis in cultured precision-cut rat, mouse and human liver slices. Food Chem Toxicol 1998; 36:455-66. [PMID: 9674953 DOI: 10.1016/s0278-6915(98)00006-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Precision-cut liver slices were prepared from male Fischer 344 rats, female CDF1 mice and humans (both male and female subjects). Liver slices were cultured for 24 hr in medium containing [3H]thymidine and either PhIP, IQ, MeIQ, MeIQx, Glu-P-1 or Trp-P-1, and then processed for auto-radiographic evaluation of unscheduled DNA synthesis (UDS). All six cooked food mutagens examined produced concentration-dependent increases in UDS in human liver slices. PhIP was the most potent compound examined, followed by MeIQx, IQ and then MeIQ, Glu-P-1 and Trp-P-1. Significant increases in UDS were observed with PhIP, IQ and MeIQx at concentrations as low as 5 microM in the culture medium. The same rank order of potency was not apparent in either rat or mouse liver slices. In rat liver slices only MeIQ significantly induced UDS, although positive results were obtained with two other genotoxins, namely 2-acetylaminofluorene and aflatoxin B1. Apart from MeIQx, all the cooked food mutagens produced significant increases in UDS in mouse liver slices. This study demonstrates the usefulness of precision-cut liver slices to evaluate species differences in xenobiotic-induced genotoxicity. Both marked compound and species differences in induction of UDS were observed. The data provide further evidence that dietary cooked food mutagens are potential human carcinogens.
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Beamand JA, Price RJ, Phillips JC, Butler WH, Jones GD, Osimitz TG, Gabriel KL, Preiss FJ, Lake BG. Lack of effect of piperonyl butoxide on unscheduled DNA synthesis in precision-cut human liver slices. Mutat Res 1996; 371:273-82. [PMID: 9008729 DOI: 10.1016/s0165-1218(96)90116-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this study the effect of piperonyl butoxide (PBO) on unscheduled DNA synthesis in precision-cut human liver slices has been examined. Liver slices prepared from tissue samples from five human donors were cultured in medium containing [3H]thymidine and 0-2.5 mM PBO using a dynamic organ culture system. After 24 h the liver slices were processed for autoradiographic examination of UDS. As positive controls, liver slices were also cultured with three known genotoxic agents, namely 2-acetylaminofluorene (2-AAF), aflatoxin B1 (AFB1) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). UDS was quantified as the net grain count in centrilobular hepatocytes and as the percentage of centrilobular hepatocyte nuclei with > 5 and > 10 net grains. Compared to control liver slice cultures PBO had no effect on UDS. In contrast, treatment with 0.02 and 0.05 mM 2-AAF, 0.002 and 0.02 mM AFB1 and 0.005 and 0.05 mM PhIP produced significant increases in net grain counts of centrilobular hepatocytes. The greatest induction of UDS was observed in liver slices treated with 0.05 mM PhIP. Treatment with 2-AAF, AFB1 and PhIP also produced increases in the number of centrilobular hepatocyte nuclei with > 5 and > 10 net grains. At the concentrations examined neither PBO, 2-AAF nor PhIP had any significant effect on replicative DNA synthesis in 24 h cultured human liver slices. In cultured liver slices treated with 0.02, but not 0.002, mM AFB1 a significant reduction in the rate of replicative DNA synthesis was observed. These results demonstrate that PBO does not induce UDS in cultured human liver slices. However, all three positive control compounds produced marked significant increases in UDS, thus confirming the functional viability of the human liver slice preparations used in this study. In conclusion, these results provide further evidence that PBO is a non-genotoxic agent which does not damage DNA in human liver.
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