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Next-generation sequencing approaches for the study of genome and epigenome toxicity induced by sulfur mustard. Arch Toxicol 2018; 92:3443-3457. [PMID: 30155719 DOI: 10.1007/s00204-018-2294-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 08/20/2018] [Indexed: 12/19/2022]
Abstract
Sulfur mustard (SM) is an extensive nucleophilic and alkylating agent that targets different tissues. The genotoxic property of SM is the most threatening effect, because it is associated with detrimental inflammations and susceptibility to several kinds of cancer. Moreover, SM causes a wide variety of adverse effects on DNA which result in accumulation of DNA adducts, multiple mutations, aneuploidies, and epigenetic aberrations in the genome. However, these adverse effects are still not known well, possibly because no valid biomarkers have been developed for detecting them. The advent of next-generation sequencing (NGS) has provided opportunities for the characterization of these alterations with a higher level of molecular detail and cost-effectivity. The present review introduces NGS approaches for the detection of SM-induced DNA adducts, mutations, chromosomal structural variation, and epigenetic aberrations, and also comparing and contrasting them with regard to which might be most advantageous.
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Panahi Y, Fattahi A, Nejabati HR, Abroon S, Latifi Z, Akbarzadeh A, Ghasemnejad T. DNA repair mechanisms in response to genotoxicity of warfare agent sulfur mustard. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2018; 58:230-236. [PMID: 29428683 DOI: 10.1016/j.etap.2018.01.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 01/27/2018] [Accepted: 01/30/2018] [Indexed: 06/08/2023]
Abstract
Sulfur mustard (SM) is an alkylating agent that causes severe damages to the skin, eyes, and the respiratory system. DNA alkylation is one of the most critical lesions that could lead to monoadducts and cross-links, as well as DNA strand breaks. In response to these adducts, cells initiate a series of reactions to recruit specific DNA repair pathways. The main DNA repair pathways in human cells, which could be involved in the DNA SM-induced DNA damages, are base excision repair (BER), nucleotide excision repair (NER), homologous recombination (HR) and non-homologous end joining (NHEJ). There is, thus, a need for a short review to clarify which damage caused by SM is repaired by which repair pathway. Increasing our knowledge about different DNA repair mechanisms following SM exposure would lay the first step for developing new therapeutic agents to treat people exposed to SM. In this review, we describe the major DNA repair pathways, according to the DNA adducts that can be caused by SM.
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Affiliation(s)
- Yunes Panahi
- Chemical Injuries Research Center System Biology and Poisoning Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Amir Fattahi
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hamid Reza Nejabati
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sina Abroon
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Zeinab Latifi
- Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Abolfazl Akbarzadeh
- Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Tohid Ghasemnejad
- Department of Medical Genetic, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
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Rose D, Schmidt A, Brandenburger M, Sturmheit T, Zille M, Boltze J. Sulfur mustard skin lesions: A systematic review on pathomechanisms, treatment options and future research directions. Toxicol Lett 2017; 293:82-90. [PMID: 29203275 DOI: 10.1016/j.toxlet.2017.11.039] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/27/2017] [Accepted: 11/28/2017] [Indexed: 12/13/2022]
Abstract
Sulfur mustard (SM) is a chemical warfare, which has been used for one hundred years. However, its exact pathomechanisms are still incompletely understood and there is no specific therapy available so far. In this systematic review, studies published between January 2000 and July 2017 involving pathomechanisms and experimental treatments of SM-induced skin lesions were analyzed to summarize current knowledge on SM pathology, to provide an overview on novel treatment options, and to identify promising targets for future research to more effectively counter SM effects. We suggest that future studies should focus on (I) systemic effects of SM intoxication due to its distribution throughout the body, (II) removal of SM depots that continuously release active compound contributing to chronic skin damage, and (III) therapeutic options that counteract the pleiotropic effects of SM.
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Affiliation(s)
- Dorothee Rose
- Department of Translational Medicine and Cell Technology, Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Mönkhofer Weg 239a, 23562, Lübeck, Germany; Institute of Medical and Marine Biotechnology, University of Lübeck, Ratzeburger Allee 160, 23652, Lübeck, Germany
| | - Annette Schmidt
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstraße 11, 80937, Munich, Germany; Universität der Bundeswehr, Fakultät für Humanwissenschaften, Department für Sportwissenschaft, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany.
| | - Matthias Brandenburger
- Department of Translational Medicine and Cell Technology, Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Mönkhofer Weg 239a, 23562, Lübeck, Germany; Institute of Medical and Marine Biotechnology, University of Lübeck, Ratzeburger Allee 160, 23652, Lübeck, Germany
| | - Tabea Sturmheit
- Department of Translational Medicine and Cell Technology, Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Mönkhofer Weg 239a, 23562, Lübeck, Germany; Institute of Medical and Marine Biotechnology, University of Lübeck, Ratzeburger Allee 160, 23652, Lübeck, Germany
| | - Marietta Zille
- Department of Translational Medicine and Cell Technology, Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Mönkhofer Weg 239a, 23562, Lübeck, Germany; Institute of Medical and Marine Biotechnology, University of Lübeck, Ratzeburger Allee 160, 23652, Lübeck, Germany; Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Ratzeburger Allee 160, 23562, Lübeck, Germany
| | - Johannes Boltze
- Department of Translational Medicine and Cell Technology, Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Mönkhofer Weg 239a, 23562, Lübeck, Germany; Institute of Medical and Marine Biotechnology, University of Lübeck, Ratzeburger Allee 160, 23652, Lübeck, Germany
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Pohanka M, Martinkova P, Brtnicky M, Kynicky J. Changes in the oxidative stress/anti-oxidant system after exposure to sulfur mustard and antioxidant strategies in the therapy, a review. Toxicol Mech Methods 2017; 27:408-416. [DOI: 10.1080/15376516.2017.1320695] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Miroslav Pohanka
- Faculty of Military Health Sciences, University of Defense, Hradec Kralove, Czech Republic
- Department of Geology and Pedology, Mendel University in Brno, Brno, Czech Republic
| | - Pavla Martinkova
- Faculty of Military Health Sciences, University of Defense, Hradec Kralove, Czech Republic
- Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic
| | - Martin Brtnicky
- Department of Geology and Pedology, Mendel University in Brno, Brno, Czech Republic
- Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic
| | - Jindrich Kynicky
- Department of Geology and Pedology, Mendel University in Brno, Brno, Czech Republic
- Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic
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5
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Impact of topical application of sulfur mustard on mice skin and distant organs DNA repair enzyme signature. Toxicol Lett 2016; 241:71-81. [DOI: 10.1016/j.toxlet.2015.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/02/2015] [Accepted: 11/02/2015] [Indexed: 11/23/2022]
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Mangerich A, Debiak M, Birtel M, Ponath V, Balszuweit F, Lex K, Martello R, Burckhardt-Boer W, Strobelt R, Siegert M, Thiermann H, Steinritz D, Schmidt A, Bürkle A. Sulfur and nitrogen mustards induce characteristic poly(ADP-ribosyl)ation responses in HaCaT keratinocytes with distinctive cellular consequences. Toxicol Lett 2015; 244:56-71. [PMID: 26383629 DOI: 10.1016/j.toxlet.2015.09.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 11/18/2022]
Abstract
Mustard agents are potent DNA alkylating agents with mutagenic, cytotoxic and vesicant properties. They include bi-functional agents, such as sulfur mustard (SM) or nitrogen mustard (mustine, HN2), as well as mono-functional agents, such as "half mustard" (CEES). Whereas SM has been used as a chemical warfare agent, several nitrogen mustard derivatives, such as chlorambucil and cyclophosphamide, are being used as established chemotherapeutics. Upon induction of specific forms of genotoxic stimuli, several poly(ADP-ribose) polymerases (PARPs) synthesize the nucleic acid-like biopolymer poly(ADP-ribose) (PAR) by using NAD(+) as a substrate. Previously, it was shown that SM triggers cellular poly(ADP-ribosyl) ation (PARylation), but so far this phenomenon is poorly characterized. In view of the protective effects of PARP inhibitors, the latter have been proposed as a treatment option of SM-exposed victims. In an accompanying article (Debiak et al., 2016), we have provided an optimized protocol for the analysis of the CEES-induced PARylation response in HaCaT keratinocytes, which forms an experimental basis to further analyze mustard-induced PARylation and its functional consequences, in general. Thus, in the present study, we performed a comprehensive characterization of the PARylation response in HaCaT cells after treatment with four different mustard agents, i.e., SM, CEES, HN2, and chlorambucil, on a qualitative, quantitative and functional level. In particular, we recorded substance-specific as well as dose- and time-dependent PARylation responses using independent bioanalytical methods based on single-cell immuno-fluorescence microscopy and quantitative isotope dilution mass spectrometry. Furthermore, we analyzed if and how PARylation contributes to mustard-induced toxicity by treating HaCaT cells with CEES, SM, and HN2 in combination with the clinically relevant PARP inhibitor ABT888. As evaluated by a novel immunofluorescence-based protocol for the detection of N7-ETE-guanine DNA adducts, the excision rate of CEES-induced DNA adducts was not affected by PARP inhibition. Furthermore, while CEES induced moderate changes in cellular NAD(+) levels, annexin V/PI flow cytometry analysis revealed that these changes did not affect CEES-induced short-term cytotoxicity 24h after treatment. In contrast, PARP inhibition impaired cell proliferation and clonogenic survival, and potentiated micronuclei formation of HaCaT cells upon CEES treatment. Similarly, PARP inhibition affected clonogenic survival of cells treated with bi-functional mustards such as SM and HN2. In conclusion, we demonstrate that PARylation plays a functional role in mustard-induced cellular stress response with substance-specific differences. Since PARP inhibitors exhibit therapeutic potential to treat SM-related pathologies and to sensitize cancer cells for mustard-based chemotherapy, potential long-term effects of PARP inhibition on genomic stability and carcinogenesis should be carefully considered when pursuing such a strategy.
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Affiliation(s)
- Aswin Mangerich
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Malgorzata Debiak
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Matthias Birtel
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Viviane Ponath
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Frank Balszuweit
- Bundeswehr Institute of Pharmacology and Toxicology, 80937 Munich, Germany
| | - Kirsten Lex
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Rita Martello
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Waltraud Burckhardt-Boer
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany
| | - Romano Strobelt
- Bundeswehr Institute of Pharmacology and Toxicology, 80937 Munich, Germany
| | - Markus Siegert
- Bundeswehr Institute of Pharmacology and Toxicology, 80937 Munich, Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, 80937 Munich, Germany
| | - Dirk Steinritz
- Bundeswehr Institute of Pharmacology and Toxicology, 80937 Munich, Germany; Walther-Straub-Institute of Pharmacology and Toxicology, 80336 Munich, Germany
| | - Annette Schmidt
- Bundeswehr Institute of Pharmacology and Toxicology, 80937 Munich, Germany
| | - Alexander Bürkle
- University of Konstanz, Molecular Toxicology Group, Department of Biology, 78457 Konstanz, Germany.
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Inturi S, Tewari-Singh N, Agarwal C, White CW, Agarwal R. Activation of DNA damage repair pathways in response to nitrogen mustard-induced DNA damage and toxicity in skin keratinocytes. Mutat Res 2014; 763-764:53-63. [PMID: 24732344 DOI: 10.1016/j.mrfmmm.2014.04.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 03/18/2014] [Accepted: 04/03/2014] [Indexed: 01/24/2023]
Abstract
Nitrogen mustard (NM), a structural analog of chemical warfare agent sulfur mustard (SM), forms adducts and crosslinks with DNA, RNA and proteins. Here we studied the mechanism of NM-induced skin toxicity in response to double strand breaks (DSBs) resulting in cell cycle arrest to facilitate DNA repair, as a model for developing countermeasures against vesicant-induced skin injuries. NM exposure of mouse epidermal JB6 cells decreased cell growth and caused S-phase arrest. Consistent with these biological outcomes, NM exposure also increased comet tail extent moment and the levels of DNA DSB repair molecules phospho H2A.X Ser139 and p53 Ser15 indicating NM-induced DNA DSBs. Since DNA DSB repair occurs via non homologous end joining pathway (NHEJ) or homologous recombination repair (HRR) pathways, next we studied these two pathways and noted their activation as defined by an increase in phospho- and total DNA-PK levels, and the formation of Rad51 foci, respectively. To further analyze the role of these pathways in the cellular response to NM-induced cytotoxicity, NHEJ and HRR were inhibited by DNA-PK inhibitor NU7026 and Rad51 inhibitor BO2, respectively. Inhibition of NHEJ did not sensitize cells to NM-induced decrease in cell growth and cell cycle arrest. However, inhibition of the HRR pathway caused a significant increase in cell death, and prolonged G2M arrest following NM exposure. Together, our findings, indicating that HRR is the key pathway involved in the repair of NM-induced DNA DSBs, could be useful in developing new therapeutic strategies against vesicant-induced skin injury.
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Affiliation(s)
- Swetha Inturi
- Department of Pharmaceutical Sciences, University of Colorado Anchutz Medical Campus, Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - Neera Tewari-Singh
- Department of Pharmaceutical Sciences, University of Colorado Anchutz Medical Campus, Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - Chapla Agarwal
- Department of Pharmaceutical Sciences, University of Colorado Anchutz Medical Campus, Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045, USA
| | - Carl W White
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Rajesh Agarwal
- Department of Pharmaceutical Sciences, University of Colorado Anchutz Medical Campus, Skaggs School of Pharmacy and Pharmaceutical Sciences, Aurora, CO 80045, USA.
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Jowsey PA, Williams FM, Blain PG. DNA damage responses in cells exposed to sulphur mustard. Toxicol Lett 2012; 209:1-10. [DOI: 10.1016/j.toxlet.2011.11.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 10/26/2011] [Accepted: 11/09/2011] [Indexed: 12/25/2022]
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Liu S, Wu M, Zhang Z. Involvement of DNA polymerase beta in repairing oxidative damages induced by antitumor drug adriamycin. Toxicol Appl Pharmacol 2010; 246:163-70. [DOI: 10.1016/j.taap.2010.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/13/2010] [Accepted: 05/17/2010] [Indexed: 11/26/2022]
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10
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Jowsey PA, Williams FM, Blain PG. The role of homologous recombination in the cellular response to sulphur mustard. Toxicol Lett 2010; 197:12-8. [DOI: 10.1016/j.toxlet.2010.04.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 04/21/2010] [Accepted: 04/23/2010] [Indexed: 01/19/2023]
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Shakarjian MP, Heck DE, Gray JP, Sinko PJ, Gordon MK, Casillas RP, Heindel ND, Gerecke DR, Laskin DL, Laskin JD. Mechanisms mediating the vesicant actions of sulfur mustard after cutaneous exposure. Toxicol Sci 2009; 114:5-19. [PMID: 19833738 DOI: 10.1093/toxsci/kfp253] [Citation(s) in RCA: 157] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Sulfur mustard (SM), a chemical weapon first employed during World War I, targets the skin, eyes, and lung. It remains a significant military and civilian threat. The characteristic response of human skin to SM involves erythema of delayed onset, followed by edema with inflammatory cell infiltration, the appearance of large blisters in the affected area, and a prolonged healing period. Several in vivo and in vitro models have been established to understand the pathology and investigate the mechanism of action of this vesicating agent in the skin. SM is a bifunctional alkylating agent which reacts with many targets including lipids, proteins, and DNA, forming both intra- and intermolecular cross-links. Despite the relatively nonselective chemical reactivity of this agent, basal keratinocytes are more sensitive, and blistering involves detachment of these cells from their basement membrane adherence zones. The sequence and manner in which these cells die and detach is still unresolved. Much has been discovered over the past two decades with respect to the mechanisms of SM-induced cytotoxicity and the intracellular and extracellular targets of this vesicant. In this review, the effects of SM exposure on the skin are described, as well as potential mechanisms mediating its actions. Successful therapy for SM poisoning will depend on following new mechanistic leads to develop drugs that target one or more of its sites of action.
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Affiliation(s)
- Michael P Shakarjian
- Department of Environmental Health Science, School of Health Sciences and Practice, Institute of Public Health, New York Medical College, Valhalla, New York 10595, USA
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Kehe K, Thiermann H, Balszuweit F, Eyer F, Steinritz D, Zilker T. Acute effects of sulfur mustard injury—Munich experiences. Toxicology 2009; 263:3-8. [DOI: 10.1016/j.tox.2009.04.060] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Revised: 04/20/2009] [Accepted: 04/21/2009] [Indexed: 10/20/2022]
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Jowsey PA, Williams FM, Blain PG. DNA damage, signalling and repair after exposure of cells to the sulphur mustard analogue 2-chloroethyl ethyl sulphide. Toxicology 2009; 257:105-12. [DOI: 10.1016/j.tox.2008.12.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 11/28/2008] [Accepted: 12/01/2008] [Indexed: 11/28/2022]
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Kisby GE, Olivas A, Park T, Churchwell M, Doerge D, Samson LD, Gerson SL, Turker MS. DNA repair modulates the vulnerability of the developing brain to alkylating agents. DNA Repair (Amst) 2009; 8:400-12. [PMID: 19162564 DOI: 10.1016/j.dnarep.2008.12.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2008] [Revised: 12/01/2008] [Accepted: 12/02/2008] [Indexed: 11/28/2022]
Abstract
Neurons of the developing brain are especially vulnerable to environmental agents that damage DNA (i.e., genotoxicants), but the mechanism is poorly understood. The focus of the present study is to demonstrate that DNA damage plays a key role in disrupting neurodevelopment. To examine this hypothesis, we compared the cytotoxic and DNA damaging properties of the methylating agents methylazoxymethanol (MAM) and dimethyl sulfate (DMS) and the mono- and bifunctional alkylating agents chloroethylamine (CEA) and nitrogen mustard (HN2), in granule cell neurons derived from the cerebellum of neonatal wild type mice and three transgenic DNA repair strains. Wild type cerebellar neurons were significantly more sensitive to the alkylating agents DMS and HN2 than neuronal cultures treated with MAM or the half-mustard CEA. Parallel studies with neuronal cultures from mice deficient in alkylguanine DNA glycosylase (Aag(-/-)) or O(6)-methylguanine methyltransferase (Mgmt(-/-)), revealed significant differences in the sensitivity of neurons to all four genotoxicants. Mgmt(-/-) neurons were more sensitive to MAM and HN2 than the other genotoxicants and wild type neurons treated with either alkylating agent. In contrast, Aag(-/-) neurons were for the most part significantly less sensitive than wild type or Mgmt(-/-) neurons to MAM and HN2. Aag(-/-) neurons were also significantly less sensitive than wild type neurons treated with either DMS or CEA. Granule cell development and motor function were also more severely disturbed by MAM and HN2 in Mgmt(-/-) mice than in comparably treated wild type mice. In contrast, cerebellar development and motor function were well preserved in MAM-treated Aag(-/-) or MGMT-overexpressing (Mgmt(Tg+)) mice, even as compared with wild type mice suggesting that AAG protein increases MAM toxicity, whereas MGMT protein decreases toxicity. Surprisingly, neuronal development and motor function were severely disturbed in Mgmt(Tg+) mice treated with HN2. Collectively, these in vitro and in vivo studies demonstrate that the type of DNA lesion and the efficiency of DNA repair are two important factors that determine the vulnerability of the developing brain to long-term injury by a genotoxicant.
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Affiliation(s)
- G E Kisby
- Center for Research on Occupational and Environmental Toxicology, Oregon Health & Science University, Portland, OR 97239, United States.
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