1
|
Babosan A, Skurnik D, Muggeo A, Pier G, Baharoglu Z, Jové T, Ploy MC, Griveau S, Bedioui F, Vergnolle S, Moussalih S, de Champs C, Mazel D, Guillard T. A qnr-plasmid allows aminoglycosides to induce SOS in Escherichia coli. eLife 2022; 11:69511. [PMID: 35037621 PMCID: PMC8789287 DOI: 10.7554/elife.69511] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 01/12/2022] [Indexed: 11/16/2022] Open
Abstract
The plasmid-mediated quinolone resistance (PMQR) genes have been shown to promote high-level bacterial resistance to fluoroquinolone antibiotics, potentially leading to clinical treatment failures. In Escherichia coli, sub-minimum inhibitory concentrations (sub-MICs) of the widely used fluoroquinolones are known to induce the SOS response. Interestingly, the expression of several PMQR qnr genes is controlled by the SOS master regulator, LexA. During the characterization of a small qnrD-plasmid carried in E. coli, we observed that the aminoglycosides become able to induce the SOS response in this species, thus leading to the elevated transcription of qnrD. Our findings show that the induction of the SOS response is due to nitric oxide (NO) accumulation in the presence of sub-MIC of aminoglycosides. We demonstrated that the NO accumulation is driven by two plasmid genes, ORF3 and ORF4, whose products act at two levels. ORF3 encodes a putative flavin adenine dinucleotide (FAD)-binding oxidoreductase which helps NO synthesis, while ORF4 codes for a putative fumarate and nitrate reductase (FNR)-type transcription factor, related to an O2-responsive regulator of hmp expression, able to repress the Hmp-mediated NO detoxification pathway of E. coli. Thus, this discovery, that other major classes of antibiotics may induce the SOS response could have worthwhile implications for antibiotic stewardship efforts in preventing the emergence of resistance.
Collapse
Affiliation(s)
- Anamaria Babosan
- Inserm UMR-S 1250 P3Cell, SFR CAP-Santé, Université de Reims-Champagne-Ardenne, Reims, France
| | - David Skurnik
- Institut Necker-Enfants Malades, Inserm U1151-Equipe 11, Université Paris Descartes, Paris, France
| | - Anaëlle Muggeo
- Inserm UMR-S 1250 P3Cell, SFR CAP-Santé, Université de Reims-Champagne-Ardenne, Reims, France
| | - Gerald Pier
- Department of Medicine, Brigham and Women's Hospital, Boston, United States
| | - Zeynep Baharoglu
- Unité Plasticité du Génome Bactérien, CNRS UMR3525, Institut Pasteur, Paris, France
| | - Thomas Jové
- CHU Limoges, RESINFIT, UMR 1092, Université de Limoges, Inserm, Limoges, France
| | - Marie-Cécile Ploy
- CHU Limoges, RESINFIT, UMR 1092, Université de Limoges, Inserm, Limoges, France
| | - Sophie Griveau
- Institute of Chemistry for Life and Health Sciences, PSL Research University, CNRS, Paris, France
| | - Fethi Bedioui
- Institute of Chemistry for Life and Health Sciences, PSL Research University, CNRS, Paris, France
| | | | - Sophie Moussalih
- Inserm UMR-S 1250 P3Cell, SFR CAP-Santé, Université de Reims-Champagne-Ardenne, Reims, France
| | - Christophe de Champs
- Inserm UMR-S 1250 P3Cell, SFR CAP-Santé, Université de Reims-Champagne-Ardenne, Reims, France
| | - Didier Mazel
- Unité Plasticité du Génome Bactérien, CNRS UMR3525, Institut Pasteur, Paris, France
| | - Thomas Guillard
- Inserm UMR-S 1250 P3Cell, SFR CAP-Santé, Université de Reims-Champagne-Ardenne, Reims, France
| |
Collapse
|
2
|
Oxidative-Antioxidant Imbalance and Impaired Glucose Metabolism in Schizophrenia. Biomolecules 2020; 10:biom10030384. [PMID: 32121669 PMCID: PMC7175146 DOI: 10.3390/biom10030384] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/24/2020] [Accepted: 02/26/2020] [Indexed: 02/07/2023] Open
Abstract
Schizophrenia is a neurodevelopmental disorder featuring chronic, complex neuropsychiatric features. The etiology and pathogenesis of schizophrenia are not fully understood. Oxidative-antioxidant imbalance is a potential determinant of schizophrenia. Oxidative, nitrosative, or sulfuric damage to enzymes of glycolysis and tricarboxylic acid cycle, as well as calcium transport and ATP biosynthesis might cause impaired bioenergetics function in the brain. This could explain the initial symptoms, such as the first psychotic episode and mild cognitive impairment. Another concept of the etiopathogenesis of schizophrenia is associated with impaired glucose metabolism and insulin resistance with the activation of the mTOR mitochondrial pathway, which may contribute to impaired neuronal development. Consequently, cognitive processes requiring ATP are compromised and dysfunctions in synaptic transmission lead to neuronal death, preceding changes in key brain areas. This review summarizes the role and mutual interactions of oxidative damage and impaired glucose metabolism as key factors affecting metabolic complications in schizophrenia. These observations may be a premise for novel potential therapeutic targets that will delay not only the onset of first symptoms but also the progression of schizophrenia and its complications.
Collapse
|
3
|
Ferguson LR. Chronic inflammation and mutagenesis. Mutat Res 2010; 690:3-11. [PMID: 20223251 DOI: 10.1016/j.mrfmmm.2010.03.007] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 02/20/2010] [Accepted: 03/02/2010] [Indexed: 02/08/2023]
Abstract
Inflammation is a necessary part of the immune response. However, when inflammation persists, the resultant state of chronic inflammation may have a number of secondary consequences associated with increased risk of chronic disease. Among these is an increased rate of mutation. There is evidence to suggest that the accumulation of reactive oxygen and nitrogen species may be a causal factor in chronic inflammation. These reactive species are also produced through the oxidative burst associated with the inflammatory process, and may interact with various cellular components including proteins, lipids and, most important for mutagenesis, nucleic acids. DNA strand breaks are commonly produced, leading to chromosomal mutation. Oxidized bases, abasic sites, DNA-DNA intrastrand adducts, and DNA-protein cross-links also occur. Not only do the nucleic acid products act directly as pro-mutagenic lesions, lipid peroxidation products may also lead to secondary DNA damage, including pro-mutagenic exocyclic DNA adducts. While frameshift and chromosomal mutations have been associated with chronic inflammation, much of the evidence reveals base pair substitution mutations associated with polymerase stalling near the lesions, and base pair mis-incorporation. There are also indirect effects of ROS/RNS through inhibition of DNA repair enzymes and/or effects on metabolic activation of known carcinogens. Certain disease states, including the Inflammatory bowel diseases, Crohn's disease and ulcerative colitis are associated with enhanced levels of chronic inflammation, and show evidence of enhanced levels of genetic damage in the colonic mucosa. Mutations may provide at least part of the cause of enhanced susceptibility to chronic diseases associated with chronic inflammation.
Collapse
Affiliation(s)
- Lynnette R Ferguson
- Discipline of Nutrition and ACSRC, FM&HS, The University of Auckland, Auckland, New Zealand.
| |
Collapse
|
4
|
Doi A, Pack SP, Makino K. Comparison of the molecular influences of NO-induced lesions in DNA strands on the reactivity of polynucleotide kinases, DNA ligases and DNA polymerases. J Biochem 2010; 147:697-703. [DOI: 10.1093/jb/mvq003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
5
|
Pack SP, Doi A, Choi YS, Kodaki T, Makino K. Biomolecular response of oxanine in DNA strands to T4 polynucleotide kinase, T4 DNA ligase, and restriction enzymes. Biochem Biophys Res Commun 2010; 391:118-22. [DOI: 10.1016/j.bbrc.2009.11.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Accepted: 11/04/2009] [Indexed: 10/20/2022]
|
6
|
Nakano T, Katafuchi A, Matsubara M, Terato H, Tsuboi T, Masuda T, Tatsumoto T, Pack SP, Makino K, Croteau DL, Van Houten B, Iijima K, Tauchi H, Ide H. Homologous recombination but not nucleotide excision repair plays a pivotal role in tolerance of DNA-protein cross-links in mammalian cells. J Biol Chem 2009; 284:27065-76. [PMID: 19674975 PMCID: PMC2785636 DOI: 10.1074/jbc.m109.019174] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Revised: 08/06/2009] [Indexed: 11/06/2022] Open
Abstract
DNA-protein cross-links (DPCs) are unique among DNA lesions in their unusually bulky nature. The steric hindrance imposed by cross-linked proteins (CLPs) will hamper DNA transactions, such as replication and transcription, posing an enormous threat to cells. In bacteria, DPCs with small CLPs are eliminated by nucleotide excision repair (NER), whereas oversized DPCs are processed exclusively by RecBCD-dependent homologous recombination (HR). Here we have assessed the roles of NER and HR for DPCs in mammalian cells. We show that the upper size limit of CLPs amenable to mammalian NER is relatively small (8-10 kDa) so that NER cannot participate in the repair of chromosomal DPCs in mammalian cells. Moreover, CLPs are not polyubiquitinated and hence are not subjected to proteasomal degradation prior to NER. In contrast, HR constitutes the major pathway in tolerance of DPCs as judged from cell survival and RAD51 and gamma-H2AX nuclear foci formation. Induction of DPCs results in the accumulation of DNA double strand breaks in HR-deficient but not HR-proficient cells, suggesting that fork breakage at the DPC site initiates HR and reactivates the stalled fork. DPCs activate both ATR and ATM damage response pathways, but there is a time lag between two responses. These results highlight the differential involvement of NER in the repair of DPCs in bacterial and mammalian cells and demonstrate the versatile and conserved role of HR in tolerance of DPCs among species.
Collapse
Affiliation(s)
- Toshiaki Nakano
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Atsushi Katafuchi
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Mayumi Matsubara
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Hiroaki Terato
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Tomohiro Tsuboi
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Tasuku Masuda
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Takahiro Tatsumoto
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Seung Pil Pack
- the Department of Biotechnology and Bioinformatics, Korea University, Jochiwon, Chungnam 339-700, Korea
| | - Keisuke Makino
- the Institute of Advanced Energy, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Deborah L. Croteau
- the Laboratory of Molecular Genetics, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, and
| | - Bennett Van Houten
- the Laboratory of Molecular Genetics, NIEHS, National Institutes of Health, Research Triangle Park, North Carolina 27709, and
| | - Kenta Iijima
- the **Department of Environmental Sciences, Faculty of Science, Ibaraki University, Bunkyo 2-1-1, Mito, Ibaraki 310-8512, Japan
| | - Hiroshi Tauchi
- the **Department of Environmental Sciences, Faculty of Science, Ibaraki University, Bunkyo 2-1-1, Mito, Ibaraki 310-8512, Japan
| | - Hiroshi Ide
- From the Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| |
Collapse
|
7
|
Genetic analysis of repair and damage tolerance mechanisms for DNA-protein cross-links in Escherichia coli. J Bacteriol 2009; 191:5657-68. [PMID: 19617358 DOI: 10.1128/jb.00417-09] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
DNA-protein cross-links (DPCs) are unique among DNA lesions in their unusually bulky nature. We have recently shown that nucleotide excision repair (NER) and RecBCD-dependent homologous recombination (HR) collaboratively alleviate the lethal effect of DPCs in Escherichia coli. In this study, to gain further insight into the damage-processing mechanism for DPCs, we assessed the sensitivities of a panel of repair-deficient E. coli mutants to DPC-inducing agents, including formaldehyde (FA) and 5-azacytidine (azaC). We show here that the damage tolerance mechanism involving HR and subsequent replication restart (RR) provides the most effective means of cell survival against DPCs. Translesion synthesis does not serve as an alternative damage tolerance mechanism for DPCs in cell survival. Elimination of DPCs from the genome relies primarily on NER, which provides a second and moderately effective means of cell survival against DPCs. Interestingly, Cho rather than UvrC seems to be an effective nuclease for the NER of DPCs. Together with the genes responsible for HR, RR, and NER, the mutation of genes involved in several aspects of DNA repair and transactions, such as recQ, xth nfo, dksA, and topA, rendered cells slightly but significantly sensitive to FA but not azaC, possibly reflecting the complexity of DPCs or cryptic lesions induced by FA. UvrD may have an additional role outside NER, since the uvrD mutation conferred a slight azaC sensitivity on cells. Finally, DNA glycosylases mitigate azaC toxicity, independently of the repair of DPCs, presumably by removing 5-azacytosine or its degradation product from the chromosome.
Collapse
|
8
|
Akbari M, Krokan HE. Cytotoxicity and mutagenicity of endogenous DNA base lesions as potential cause of human aging. Mech Ageing Dev 2008; 129:353-65. [PMID: 18355895 DOI: 10.1016/j.mad.2008.01.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2007] [Revised: 01/25/2008] [Accepted: 01/28/2008] [Indexed: 11/26/2022]
Abstract
Endogenous factors constitute a substantial source of damage to the genomic DNA. The type of damage includes a number of different base lesions and single- and double-strand breaks. Unrepaired DNA damage can give rise to mutations and may cause cell death. A number of studies have demonstrated an association between aging and the accumulation of DNA damage. This may be attributed to reduced DNA repair with age, although this is apparently not a general feature for all types of damage and repair mechanisms. Therefore, detailed studies that improve our knowledge of DNA repair systems as well as mutagenic and toxic effects of DNA lesions will help us to gain a better insight into the mechanisms of aging. The aim of this review is to provide a brief description of cytotoxic and mutagenic endogenous DNA lesions that are mainly repaired by base excision repair and single-strand break repair pathways and to discuss the potential role of DNA lesions and DNA repair dysfunction in the onset of human aging.
Collapse
Affiliation(s)
- Mansour Akbari
- Department of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
| | | |
Collapse
|
9
|
Dong L, Meira LB, Hazra TK, Samson LD, Cao W. Oxanine DNA glycosylase activities in mammalian systems. DNA Repair (Amst) 2007; 7:128-34. [PMID: 17954039 DOI: 10.1016/j.dnarep.2007.09.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Revised: 09/12/2007] [Accepted: 09/12/2007] [Indexed: 11/28/2022]
Abstract
DNA bases carrying an exocyclic amino group, namely adenine (A), guanine (G) and cytosine (C), encounter deamination under nitrosative stress. Oxanine (O), derived from deamination of guanine, is a cytotoxic and potentially mutagenic lesion and studies of its enzymatic repair are limited. Previously, we reported that the murine alkyladenine glycosylase (Aag) acts as an oxanine DNA glycosylase (JBC (2004), 279: 38177). Here, we report our recent findings on additional oxanine DNA glycosylase (ODG) activities in Aag knockout mouse tissues and other mammalian tissues. Analysis of the partially purified proteins from the mammalian cell extracts indicated the existence of ODG enzymes in addition to Aag. Data obtained from oxanine DNA cleavage assays using purified human glycosylases demonstrated that two known glycosylases, hNEIL1 and hSMUG1, contained weak but detectable ODG activities. ODG activity was the highest in hAAG and lowest in hSMUG1.
Collapse
Affiliation(s)
- Liang Dong
- Department of Genetics and Biochemistry, South Carolina Experiment Station, Clemson University, Room 219, Biosystems Research Complex, 51 New Cherry Street, Clemson, SC 29634, United States
| | | | | | | | | |
Collapse
|
10
|
Nucleotide excision repair and homologous recombination systems commit differentially to the repair of DNA-protein crosslinks. Mol Cell 2007; 28:147-58. [PMID: 17936711 DOI: 10.1016/j.molcel.2007.07.029] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Revised: 06/30/2007] [Accepted: 07/30/2007] [Indexed: 11/21/2022]
Abstract
DNA-protein crosslinks (DPCs)-where proteins are covalently trapped on the DNA strand-block the progression of replication and transcription machineries and hence hamper the faithful transfer of genetic information. However, the repair mechanism of DPCs remains largely elusive. Here we have analyzed the roles of nucleotide excision repair (NER) and homologous recombination (HR) in the repair of DPCs both in vitro and in vivo using a bacterial system. Several lines of biochemical and genetic evidence show that both NER and HR commit to the repair or tolerance of DPCs, but differentially. NER repairs DPCs with crosslinked proteins of sizes less than 12-14 kDa, whereas oversized DPCs are processed exclusively by RecBCD-dependent HR. These results highlight how NER and HR are coordinated when cells need to deal with unusually bulky DNA lesions such as DPCs.
Collapse
|
11
|
Pack SP, Kamisetty NK, Nonogawa M, Devarayapalli KC, Ohtani K, Yamada K, Yoshida Y, Kodaki T, Makino K. Direct immobilization of DNA oligomers onto the amine-functionalized glass surface for DNA microarray fabrication through the activation-free reaction of oxanine. Nucleic Acids Res 2007; 35:e110. [PMID: 17715142 PMCID: PMC2034461 DOI: 10.1093/nar/gkm619] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Oxanine having an O-acylisourea structure was explored to see if its reactivity with amino group is useful in DNA microarray fabrication. By the chemical synthesis, a nucleotide unit of oxanine (Oxa-N) was incorporated into the 5′-end of probe DNA with or without the -(CH2)n- spacers (n = 3 and 12) and found to immobilize the probe DNA covalently onto the NH2-functionalized glass slide by one-pot reaction, producing the high efficiency of the target hybridization. The methylene spacer, particularly the longer one, generated higher efficiency of the target recognition although there was little effect on the amount of the immobilized DNA oligomers. The post-spotting treatment was also carried out under the mild conditions (at 25 or 42°C) and the efficiencies of the immobilization and the target recognition were evaluated similarly, and analogous trends were obtained. It has also been determined under the mild conditions that the humidity and time of the post-spotting treatment, pH of the spotting solution and the synergistic effects with UV-irradiation largely contribute to the desired immobilization and resulting target recognition. Immobilization of DNA oligomer by use of Oxa-N on the NH2-functionalized surface without any activation step would be employed as one of the advanced methods for generating DNA-conjugated solid surface.
Collapse
Affiliation(s)
- Seung Pil Pack
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Nagendra Kumar Kamisetty
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Mitsuru Nonogawa
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Kamakshaiah Charyulu Devarayapalli
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Kairi Ohtani
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Kazunari Yamada
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Yasuko Yoshida
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Tsutomu Kodaki
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Keisuke Makino
- Institute of Advanced Energy, Kyoto University, CREST, JST (Japan Science and Technology Agency), Kyoto University, Gokasho, Uji 611-0011, NGK Insulators, Ltd, GENESHOT project, Mizuho, Nagoya 467-8530 and Kyoto Nanotechnology Cluster, Kyoto University, Gokasho, Uji 611-0011, Japan
- *To whom correspondence should be addressed. +81 774 38 3517+81 774 38 3524
| |
Collapse
|
12
|
Dong M, Dedon PC. Relatively small increases in the steady-state levels of nucleobase deamination products in DNA from human TK6 cells exposed to toxic levels of nitric oxide. Chem Res Toxicol 2006; 19:50-7. [PMID: 16411656 PMCID: PMC2515361 DOI: 10.1021/tx050252j] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nitric oxide (NO) is a physiologically important molecule that has been implicated in the pathophysiology of diseases associated with chronic inflammation, such as cancer. While the complicated chemistry of NO-mediated genotoxicity has been extensively study in vitro, neither the spectrum of DNA lesions nor their consequences in vivo have been rigorously defined. We have approached this problem by exposing human TK6 lymphoblastoid cells to controlled steady-state concentrations of 1.75 or 0.65 microM NO along with 186 microM O2 in a recently developed reactor that avoids the anomalous gas-phase chemistry of NO and approximates the conditions at sites of inflammation in tissues. The resulting spectrum of nucleobase deamination products was defined using a recently developed liquid chromatography/mass spectrometry (LC/MS) method, and the results were correlated with cytotoxicity and apoptosis. A series of control experiments revealed the necessity of using dC and dA deaminase inhibitors to avoid adventitious formation of 2'-deoxyuridine (dU) and 2'-deoxyinosine (dI), respectively, during DNA isolation and processing. Exposure of TK6 cells to 1.75 microM NO and 186 microM O2 for 12 h (1260 microM x min dose) resulted in 32% loss of cell viability measured immediately after exposure and 87% cytotoxicity after a 24 h recovery period. The same exposure resulted in 3.5-, 3.8-, and 4.1-fold increases in dX, dI, and dU, respectively, to reach the following levels: dX, 7 (+/- 1) per 10(6) nt; dI, 25 (+/- 2.1) per 10(6) nt; and dU, 40 (+/- 3.8) per 10(6) nt. dO was not detected above the limit of detection of 6 lesions per 10(7) nt in 50 microg of DNA. A 12 h exposure to 0.65 microM NO and 190 microM O2 (468 microM x min dose) caused 1.7-, 1.8-, and 2.0-fold increases in dX, dI, and dU, respectively, accompanied by a approximately 15% (+/- 3.6) reduction in cell viability immediately after exposure. Again, dO was not detected. These results reveal modest increases in the steady-state levels of DNA deamination products in cells exposed to relatively cytotoxic levels of NO. This could result from limited nitrosative chemistry in nuclear DNA in cells exposed to NO or high levels of formation balanced by rapid repair of nucleobase deamination lesions in DNA.
Collapse
Affiliation(s)
- Min Dong
- Biological Engineering Division, NE47-277, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
| | | |
Collapse
|
13
|
Suzuki T. DNA Damage and Mutation Caused by Vital Biomolecules, Water, Nitric Oxide, and Hypochlorous Acid. Genes Environ 2006. [DOI: 10.3123/jemsge.28.48] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|