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Hudson KM, Klimczak LJ, Sterling JF, Burkholder AB, Kazanov M, Saini N, Mieczkowski PA, Gordenin DA. Glycidamide-induced hypermutation in yeast single-stranded DNA reveals a ubiquitous clock-like mutational motif in humans. Nucleic Acids Res 2023; 51:9075-9100. [PMID: 37471042 PMCID: PMC10516655 DOI: 10.1093/nar/gkad611] [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: 03/19/2023] [Revised: 06/28/2023] [Accepted: 07/10/2023] [Indexed: 07/21/2023] Open
Abstract
Mutagens often prefer specific nucleotides or oligonucleotide motifs that can be revealed by studying the hypermutation spectra in single-stranded (ss) DNA. We utilized a yeast model to explore mutagenesis by glycidamide, a simple epoxide formed endogenously in humans from the environmental toxicant acrylamide. Glycidamide caused ssDNA hypermutation in yeast predominantly in cytosines and adenines. The most frequent mutations in adenines occurred in the nAt→nGt trinucleotide motif. Base substitutions A→G in this motif relied on Rev1 translesion polymerase activity. Inactivating Rev1 did not alter the nAt trinucleotide preference, suggesting it may be an intrinsic specificity of the chemical reaction between glycidamide and adenine in the ssDNA. We found this mutational motif enriched in published sequencing data from glycidamide-treated mouse cells and ubiquitous in human cancers. In cancers, this motif was positively correlated with the single base substitution (SBS) smoking-associated SBS4 signature, with the clock-like signatures SBS1, SBS5, and was strongly correlated with smoking history and with age of tumor donors. Clock-like feature of the motif was also revealed in cells of human skin and brain. Given its pervasiveness, we propose that this mutational motif reflects mutagenic lesions to adenines in ssDNA from a potentially broad range of endogenous and exogenous agents.
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Affiliation(s)
- Kathleen M Hudson
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, US National Institutes of Health, Durham, NC 27709, USA
| | - Leszek J Klimczak
- Integrative Bioinformatics Support Group, National Institute of Environmental Health Sciences, US National Institutes of Health, Durham, NC 27709, USA
| | - Joan F Sterling
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, US National Institutes of Health, Durham, NC 27709, USA
| | - Adam B Burkholder
- Office of Environmental Science Cyberinfrastructure, National Institute of Environmental Health Sciences, US National Institutes of Health, Durham, NC 27709, USA
| | - Marat D Kazanov
- Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul, 34956, Turkey
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Natalie Saini
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, SC, 29425, USA
| | - Piotr A Mieczkowski
- Department of Genetics, School of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Dmitry A Gordenin
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, US National Institutes of Health, Durham, NC 27709, USA
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2
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Motwani HV, Eriksson L, Göpfert L, Larsen K. Reaction kinetic studies for comparison of mutagenic potency between butadiene monoxide and glycidamide. Chem Biol Interact 2018; 288:57-64. [PMID: 29653098 DOI: 10.1016/j.cbi.2018.03.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 03/13/2018] [Accepted: 03/27/2018] [Indexed: 12/13/2022]
Abstract
DNA adducts can be formed from covalent binding of electrophilic reactive compounds to the nucleophilic N- and O-atoms of the biomolecule. The O-sites on DNA, with nucleophilic strength (n) of ca. 2, is recognized as a critical site for mutagenicity. Characterization of the reactivity of electrophilic compounds at the O-sites can be used to predict their mutagenic potency in relative terms. In the present study, reaction kinetic experiments were performed for butadiene monoxide (BM) in accordance with the Swain-Scott relation using model nucleophiles representing N- and O-sites on DNA, and earlier for glycidamide (GA) using a similar approach. The epoxide from the kinetic experiments was trapped by cob(I)alamin, resulting in formation of an alkylcobalamin which was analyzed by liquid chromatography tandem mass spectrometry. The Swain-Scott relationship was used to determine selectivity constant (s) of BM and GA as 0.86 and 1.0, respectively. The rate constant for the reaction at n of 2 was extrapolated to 0.023 and 0.038 M-1 h-1 for BM and GA, respectively, implying a higher mutagenic potency per dose unit of GA compared to BM. The reaction kinetic parameters associated with mutagenic potency were also estimated by a density functional theory approach, which were in accordance to the experimental determined values. These types of reaction kinetic measures could be useful in development of a chemical reactivity based prediction tool that could aid in reduction of animal experiments in cancer risk assessment procedures for relative mutagenicity.
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Affiliation(s)
- Hitesh V Motwani
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691 Stockholm, Sweden.
| | - Lars Eriksson
- Department of Materials and Environmental Chemistry, Stockholm University, SE-10691 Stockholm, Sweden
| | - Lisa Göpfert
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691 Stockholm, Sweden
| | - Kristian Larsen
- Department of Materials and Environmental Chemistry, Stockholm University, SE-10691 Stockholm, Sweden
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3
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Parallelogram based approach for in vivo dose estimation of genotoxic metabolites in humans with relevance to reduction of animal experiments. Sci Rep 2017; 7:17560. [PMID: 29242644 PMCID: PMC5730592 DOI: 10.1038/s41598-017-17692-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/29/2017] [Indexed: 12/14/2022] Open
Abstract
When employing metabolism studies of genotoxic compounds/metabolites and cancer tests for risk estimation, low exposure doses in humans are roughly extrapolated from high exposure doses in animals. An improvement is to measure the in vivo dose, i.e. area under concentration-time curve (AUC), of the causative genotoxic agent. In the present work, we propose and evaluate a parallelogram based approach for estimation of the AUC of genotoxic metabolites that incorporates in vitro metabolic data and existing knowledge from published in vivo data on hemoglobin (Hb) adduct levels, using glycidamide (GA) as a case study compound that is the genotoxic metabolite of acrylamide (AA). The estimated value of AUC of GA per AUC of AA from the parallelogram approach vs. that from Hb adduct levels measured in vivo were in good agreement; 0.087 vs. 0.23 in human and 1.4 vs. 0.53 in rat, respectively. The described parallelogram approach is simple, and can be useful to provide an approximate estimation of the AUC of metabolites in humans at low exposure levels for which sensitive methods for analyzing the metabolites are not available, as well as aid in reduction of animal experiments for metabolism studies that are to be used for cancer risk assessment.
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4
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Carlsson H, Aasa J, Kotova N, Vare D, Sousa PFM, Rydberg P, Abramsson-Zetterberg L, Törnqvist M. Adductomic Screening of Hemoglobin Adducts and Monitoring of Micronuclei in School-Age Children. Chem Res Toxicol 2017; 30:1157-1167. [DOI: 10.1021/acs.chemrestox.6b00463] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Henrik Carlsson
- Department
of Environmental Science and Analytical Chemistry, Stockholm University, SE-106
91 Stockholm, Sweden
| | - Jenny Aasa
- Department
of Environmental Science and Analytical Chemistry, Stockholm University, SE-106
91 Stockholm, Sweden
| | | | - Daniel Vare
- Swedish National Food Agency, SE-751
26 Uppsala, Sweden
| | - Pedro F. M. Sousa
- Department
of Environmental Science and Analytical Chemistry, Stockholm University, SE-106
91 Stockholm, Sweden
| | - Per Rydberg
- Department
of Oncology-Pathology, Karolinska Institute, SE-171 77 Stockholm, Sweden
| | | | - Margareta Törnqvist
- Department
of Environmental Science and Analytical Chemistry, Stockholm University, SE-106
91 Stockholm, Sweden
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5
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Aasa J, Vare D, Motwani HV, Jenssen D, Törnqvist M. Quantification of the mutagenic potency and repair of glycidol-induced DNA lesions. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2016; 805:38-45. [PMID: 27402481 DOI: 10.1016/j.mrgentox.2016.05.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/20/2016] [Accepted: 05/26/2016] [Indexed: 11/25/2022]
Abstract
Glycidol (Gly) is an electrophilic low-molecular weight epoxide that is classified by IARC as probably carcinogenic to humans. Humans might be exposed to Gly from food, e.g. refined vegetable oils, where Gly has been found as a food process contaminant. It is therefore important to investigate and quantify the genotoxicity of Gly as a primary step towards cancer risk assessment of the human exposure. Here, quantification of the mutagenic potency expressed per dose (AUC: area under the concentration-time curve) of Gly has been performed in Chinese hamster ovary (CHO) cells, using the HPRT assay. The dose of Gly was estimated in the cell exposure medium by trapping Gly with a strong nucleophile, cob(I)alamin, to form stable cobalamin adducts for analysis by LC-MS/MS. Gly was stable in the exposure medium during the time for cell treatment, and thus the dose in vitro is the initial concentration×cell treatment time. Gly induced mutations in the hprt-gene at a rate of 0.08±0.01 mutations/10(5) cells/mMh. Through comparison with the effect of ionizing radiation in the same system a relative mutagenic potency of 9.5rad-eq./mMh was obtained, which could be used for comparison of genotoxicity of chemicals and between test systems and also in procedures for quantitative cancer risk assessment. Gly was shown to induce strand breaks, that were repaired by base excision repair. Furthermore, Gly-induced lesions, present during replication, were found to delay the replication fork elongation. From experiments with repair deficient cells, homologous recombination repair and the ERCC1-XPF complex were indicated to be recruited to support in the repair of the damage related to the stalled replication elongation. The type of DNA damage responsible for the mutagenic effect of Gly could not be concluded from the present study.
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Affiliation(s)
- Jenny Aasa
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691 Stockholm, Sweden
| | - Daniel Vare
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - Hitesh V Motwani
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691 Stockholm, Sweden
| | - Dag Jenssen
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, SE-10691 Stockholm, Sweden
| | - Margareta Törnqvist
- Department of Environmental Science and Analytical Chemistry, Stockholm University, SE-10691 Stockholm, Sweden.
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6
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Honda H, Törnqvist M, Nishiyama N, Kasamatsu T. Characterization of glycidol-hemoglobin adducts as biomarkers of exposure and in vivo dose. Toxicol Appl Pharmacol 2014; 275:213-20. [DOI: 10.1016/j.taap.2014.01.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Revised: 01/14/2014] [Accepted: 01/15/2014] [Indexed: 11/28/2022]
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7
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González-Pérez M, Gómez-Bombarelli R, Arenas-Valgañón J, Pérez-Prior MT, García-Santos MP, Calle E, Casado J. Connecting the Chemical and Biological Reactivity of Epoxides. Chem Res Toxicol 2012; 25:2755-62. [DOI: 10.1021/tx300389z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marina González-Pérez
- Departamento
de Química
física, Facultad de Ciencias Químicas, Universidad de Salamanca, Plaza de los Caídos
1-5, E-37008, Salamanca, Spain
| | - Rafael Gómez-Bombarelli
- Department of Physics, School
of Engineering and Physical Sciences, Heriot-Watt University David Brewster Building G.45, Edinburgh EH14 4AS, U. K
| | - Jorge Arenas-Valgañón
- Departamento
de Química
física, Facultad de Ciencias Químicas, Universidad de Salamanca, Plaza de los Caídos
1-5, E-37008, Salamanca, Spain
| | - M. Teresa Pérez-Prior
- Departamento de Ciencia e Ingeniería
de Materiales, Universidad Carlos III de Madrid, E-28911, Leganés, Madrid, Spain
| | - M. Pilar García-Santos
- Departamento
de Química
física, Facultad de Ciencias Químicas, Universidad de Salamanca, Plaza de los Caídos
1-5, E-37008, Salamanca, Spain
| | - Emilio Calle
- Departamento
de Química
física, Facultad de Ciencias Químicas, Universidad de Salamanca, Plaza de los Caídos
1-5, E-37008, Salamanca, Spain
| | - Julio Casado
- Departamento
de Química
física, Facultad de Ciencias Químicas, Universidad de Salamanca, Plaza de los Caídos
1-5, E-37008, Salamanca, Spain
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8
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Ao L, Cao J. Genotoxicity of Acrylamide and Glycidamide: A Review of the Studies by HPRT Gene and TK Gene Mutation Assays. Genes Environ 2012. [DOI: 10.3123/jemsge.34.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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9
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Motwani HV, Törnqvist M. Quantitative analysis by liquid chromatography–tandem mass spectrometry of glycidamide using the cob(I)alamin trapping method: Validation and application to in vitro metabolism of acrylamide. J Chromatogr A 2011; 1218:4389-94. [DOI: 10.1016/j.chroma.2011.05.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 02/22/2011] [Accepted: 05/09/2011] [Indexed: 11/29/2022]
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10
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Törnqvist M, Paulsson B, Vikström AC, Granath F. Approach for cancer risk estimation of acrylamide in food on the basis of animal cancer tests and in vivo dosimetry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2008; 56:6004-6012. [PMID: 18624431 DOI: 10.1021/jf800490s] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The question about the contribution from acrylamide (AA) in food to the cancer risk in the general population has not yet had a satisfactory answer. One point of discussion is whether AA constitutes a cancer risk through its genotoxic metabolite, glycidamide (GA), or whether other mechanism(s) could be operating. Using a relative cancer risk model, an improvement of the cancer risk estimate for dietary AA can be obtained by estimation of the genotoxic contribution to the risk. One cornerstone in this model is the in vivo dose of the causative genotoxic agent. This paper presents an evaluation, according to this model, of published AA cancer tests on the basis of in vivo doses of GA in rats exposed in the cancer tests. The present status regarding data with importance for an improved estimation of the contribution from GA to the cancer risk of AA, such as in vivo doses measured in humans, is discussed.
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11
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Clement FC, Dip R, Naegeli H. Expression profile of human cells in culture exposed to glycidamide, a reactive metabolite of the heat-induced food carcinogen acrylamide. Toxicology 2007; 240:111-24. [PMID: 17822822 DOI: 10.1016/j.tox.2007.07.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Revised: 07/27/2007] [Accepted: 07/30/2007] [Indexed: 10/23/2022]
Abstract
Recent findings of acrylamide in many common foods have sparked renewed interest in assessing human health hazards and the long-term risk associated with exposure to vinyl compounds. Acrylamide is tumorigenic at high doses in rodents and has been classified as a probable human carcinogen. However, cancer risk projections in the population remain problematic because the molecular pathogenesis of acrylamide at the low level of dietary uptake is not understood. In particular, the question of whether specific transcriptional responses may amplify or mitigate the known genotoxicity of acrylamide has never been examined. Here, we used high-density DNA microarrays and PCR validations to assess genome-wide messenger profiles induced by glycidamide, the more reactive metabolite of acrylamide. The expression changes resulting from glycidamide treatment of human epithelial cells are characterized by the induction of detoxification enzymes, several members of the glutathione system and antioxidant factors. Low-dose experiments indicate that the up-regulation of epoxide hydrolase 1 represents the most sensitive transcriptional biomarker of glycidamide exposure. At higher concentrations, glycidamide induces typical markers of tumor progression such as steroid hormone activators, positive regulators of nuclear factor-kappaB, growth stimulators and apoptosis inhibitors. Concomitantly, growth suppressors and cell adhesion molecules are down-regulated. The main implication of these findings for risk assessment is that low concentrations of glycidamide elicit cytoprotective reactions whereas transcriptional signatures associated with tumor progression may be expected only at doses that exceed the range of ordinary dietary exposures.
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Affiliation(s)
- Flurina C Clement
- Institute of Pharmacology and Toxicology, University of Zürich-Vetsuisse, Winterthurerstrasse 260, CH-8057 Zürich, Switzerland
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12
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Haglund J, Silvari V, Esmans E, Törnqvist M. Cobalamin as an analytical tool for analysis of oxirane metabolites of 1,3-butadiene: Development and validation of the method. J Chromatogr A 2006; 1119:246-50. [PMID: 16386262 DOI: 10.1016/j.chroma.2005.11.069] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Revised: 11/14/2005] [Accepted: 11/21/2005] [Indexed: 11/30/2022]
Abstract
The reduced form of vitamin B12 [cob(I)alamin] is known to be a supernucleophile, with the ability to react 10(5) times faster than standard nucleophiles. Procedures have been developed where cob(I)alamin is used as an analytical tool for the trapping of electrophilically reactive compounds. In the present work, a sensitive and accurate method for determination of reactive metabolites produced in vitro has been developed and validated. Diepoxybutane (DEB), a metabolite of 1,3-butadiene, was used as a model compound. The intermediate precursor 1,2-epoxybutene (EB) was incubated in a mouse liver S9 metabolic system and the formation of DEB was studied. Samples were taken at different times from the incubation mixture and added to the cob(I)alamin. The alkyl-cobalamins (alkyl-Cbl) formed were directly analysed by a miniaturized LC-MS/MS method and column switching. The assay was linear over the concentration range of 1.5-500 microM with acceptable precision and accuracy.
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Affiliation(s)
- J Haglund
- Department of Environmental Chemistry, Stockholm University, Sweden.
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13
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Vesper HW, Ospina M, Meyers T, Ingham L, Smith A, Gray JG, Myers GL. Automated method for measuring globin adducts of acrylamide and glycidamide at optimized Edman reaction conditions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2006; 20:959-64. [PMID: 16479554 DOI: 10.1002/rcm.2396] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The general population is exposed to acrylamide, a potential human carcinogen, through food and cigarette smoke. The assessment of human exposure to acrylamide is important in the evaluation of health risks associated with this chemical. Hemoglobin adducts of acrylamide (AA-Hb) and its primary metabolite glycidamide (GA-Hb) are established biomarkers of acrylamide exposure and methods to measure these biomarkers using modified Edman reaction are described. Only limited information about the optimal Edman reaction conditions such as pH or temperature is available for these adducts and the existing methods do not allow automation needed in biomonitoring studies. In this study, the yield of Edman products of AA-Hb and GA-Hb between pH 3-10 and at 35-55 degrees C at different time intervals, and the applicability of liquid-liquid extraction on diatomaceous earth for analyte extraction, were assessed and results were used in a new optimized method. The applicability of our optimized method was assessed by comparing results obtained with a convenience sample from 96 individuals with a conventional method. Maximum yield of Edman products was obtained between pH 6-7, heating the reaction solution at 55 degrees C for 2 h resulted in the same yields as with conventional conditions, and use of diatomaceous earth was found suitable for automated analyte extraction. Using these conditions, no difference was observed between our optimized and a conventional method. The median globin adduct values in the convenience sample are 129 pmol/g globin (range: 27-453 pmol/g globin) and 97 pmol/g globin (range: 27-240 pmol/g globin) for AA-Hb and GA-Hb, respectively. The GA-Hb/AA-Hb ratio decreases significantly with increasing AA-Hb values indicating that measurement of AA-Hb as well as GA-Hb are needed to appropriately assess human exposure to acrylamide.
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Affiliation(s)
- Hubert W Vesper
- Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy, NE (MS F-25), USA.
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14
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Paulsson B, Rannug A, Henderson AP, Golding BT, Törnqvist M, Warholm M. In vitro studies of the influence of glutathione transferases and epoxide hydrolase on the detoxification of acrylamide and glycidamide in blood. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2005; 580:53-9. [PMID: 15668107 DOI: 10.1016/j.mrgentox.2004.11.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2004] [Revised: 11/09/2004] [Accepted: 11/10/2004] [Indexed: 11/20/2022]
Abstract
Enzymes involved in the metabolism of xenobiotic substances are often polymorphic in humans. Such genetic polymorphisms may result in inter-individual differences in detoxification of certain chemicals, and as a consequence, possibly affect health-risk assessments. This present work concerns studies of the influence of polymorphic enzymes in the detoxification of acrylamide and its metabolite glycidamide. Enzymes that enhance conjugation with glutathione (GSH), the glutathione transferases (GSTs), may influence the detoxification of both acrylamide and glycidamide, whereas the enzyme epoxide hydrolase (EH) should only catalyse the hydrolysis of glycidamide. In this study, the doses of acrylamide or glycidamide measured as specific adducts to hemoglobin (Hb) were analysed in blood samples after in vitro incubation with these compounds. Blood samples from individuals with different genotypes for GSTT1 and GSTM1 were studied. No significant differences in adduct levels depending on genotype were noted. In a parallel experiment, incubation with ethylene oxide was used as positive control. In this experiment individuals carrying GSTT1 showed lower adduct level increments from ethylene oxide than individuals lacking GSTT1. Furthermore, addition of ethacrynic acid or laurylamine, compounds which inhibit GST and EH, respectively, did not affect the adduct levels. These results suggest that neither GSTs nor EH have any significant effect on the blood dose, measured as Hb-adducts over time, after exposure to acrylamide or glycidamide.
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Affiliation(s)
- Birgit Paulsson
- Department of Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden
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