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Zhao ML, Stefanick DF, Nadalutti CA, Beard WA, Wilson SH, Horton JK. Temporal recruitment of base excision DNA repair factors in living cells in response to different micro-irradiation DNA damage protocols. DNA Repair (Amst) 2023; 126:103486. [PMID: 37028218 PMCID: PMC10133186 DOI: 10.1016/j.dnarep.2023.103486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/07/2023] [Accepted: 03/20/2023] [Indexed: 04/09/2023]
Abstract
Laser micro-irradiation across the nucleus rapidly generates localized chromatin-associated DNA lesions permitting analysis of repair protein recruitment in living cells. Recruitment of three fluorescently-tagged base excision repair factors [DNA polymerase β (pol β), XRCC1 and PARP1], known to interact with one another, was compared in gene-deleted mouse embryonic fibroblasts and in those expressing the endogenous factor. A low energy micro-irradiation (LEMI) forming direct single-strand breaks and a moderate energy (MEMI) protocol that additionally creates oxidized bases were compared. Quantitative characterization of repair factor recruitment and sensitivity to clinical PARP inhibitors (PARPi) was dependent on the micro-irradiation protocol. PARP1 recruitment was biphasic and generally occurred prior to pol β and XRCC1. After LEMI, but not after MEMI, pol β and XRCC1 recruitment was abolished by the PARPi veliparib. Consistent with this, pol β and XRCC1 recruitment following LEMI was considerably slower in PARP1-deficient cells. Surprisingly, the recruitment half-times and amplitudes for pol β were less affected by PARPi than were XRCC1 after MEMI suggesting there is a XRCC1-independent component for pol β recruitment. After LEMI, but not MEMI, pol β dissociation was more rapid than that of XRCC1. Unexpectedly, PARP1 dissociation was slowed in the absence of XRCC1 as well with a PARPi after LEMI but not MEMI, suggesting that XRCC1 facilitates PARP1 dissociation from specific DNA lesions. XRCC1-deficient cells showed pronounced hypersensitivity to the PARPi talazoparib correlating with its known cytotoxic PARP1 trapping activity. In contrast to DNA methylating agents, PARPi only minimally sensitized pol β and XRCC1-deficient cells to oxidative DNA damage suggesting differential binding of PARP1 to alternate repair intermediates. In summary, pol β, XRCC1, and PARP1 display recruitment kinetics that exhibit correlated and unique properties that depend on the DNA lesion and PARP activity revealing that there are multiple avenues utilized in the repair of chromatin-associated DNA.
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Affiliation(s)
- Ming-Lang Zhao
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Donna F Stefanick
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Cristina A Nadalutti
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - William A Beard
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Julie K Horton
- Genome Integrity and Structural Biology Laboratory, NIEHS, National Institutes of Health, Research Triangle Park, NC 27709, USA.
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2
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Abbasnezhad A, Salami F, Mohebbati R. A review: Systematic research approach on toxicity model of liver and kidney in laboratory animals. Animal Model Exp Med 2022; 5:436-444. [PMID: 35918879 PMCID: PMC9610155 DOI: 10.1002/ame2.12230] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 04/13/2022] [Indexed: 11/26/2022] Open
Abstract
Therapeutic experiments are commonly performed on laboratory animals to investigate the possible mechanism(s) of action of toxic agents as well as drugs or substances under consideration. The use of toxins in laboratory animal models, including rats, is intended to cause toxicity. This study aimed to investigate different models of hepatotoxicity and nephrotoxicity in laboratory animals to help researchers advance their research goals. The current narrative review used databases such as Medline, Web of Science, Scopus, and Embase and appropriate keywords until June 2021. Nephrotoxicity and hepatotoxicity models derived from some toxic agents such as cisplatin, acetaminophen, doxorubicin, some anticancer drugs, and other materials through various signaling pathways are investigated. To understand the models of renal or hepatotoxicity in laboratory animals, we have provided a list of toxic agents and their toxicity procedures in this review.
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Affiliation(s)
- Abbasali Abbasnezhad
- Department of Physiology, Faculty of Medicine, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Fatemeh Salami
- Department of Physiology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Reza Mohebbati
- Department of Physiology, Faculty of Medicine, Gonabad University of Medical Sciences, Gonabad, Iran.,Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
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3
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Jiang C, Ward NP, Prieto-Farigua N, Kang YP, Thalakola A, Teng M, DeNicola GM. A CRISPR screen identifies redox vulnerabilities for KEAP1/NRF2 mutant non-small cell lung cancer. Redox Biol 2022; 54:102358. [PMID: 35667246 PMCID: PMC9168196 DOI: 10.1016/j.redox.2022.102358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 05/17/2022] [Accepted: 05/30/2022] [Indexed: 12/02/2022] Open
Abstract
The redox regulator NRF2 is hyperactivated in a large percentage of non-small cell lung cancer (NSCLC) cases, which is associated with chemotherapy and radiation resistance. To identify redox vulnerabilities for KEAP1/NRF2 mutant NSCLC, we conducted a CRISPR-Cas9-based negative selection screen for antioxidant enzyme genes whose loss sensitized cells to sub-lethal concentrations of the superoxide (O2•-) -generating drug β-Lapachone. While our screen identified expected hits in the pentose phosphate pathway, the thioredoxin-dependent antioxidant system, and glutathione reductase, we also identified the mitochondrial superoxide dismutase 2 (SOD2) as one of the top hits. Surprisingly, β-Lapachone did not generate mitochondrial O2•- but rather SOD2 loss enhanced the efficacy of β-Lapachone due to loss of iron-sulfur protein function, loss of mitochondrial ATP maintenance and deficient NADPH production. Importantly, inhibition of mitochondrial electron transport activity sensitized cells to β-Lapachone, demonstrating that these effects may be translated to increase ROS sensitivity therapeutically.
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Affiliation(s)
- Chang Jiang
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA.
| | - Nathan P Ward
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA
| | - Nicolas Prieto-Farigua
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA
| | - Yun Pyo Kang
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA
| | - Anish Thalakola
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA
| | - Mingxiang Teng
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA
| | - Gina M DeNicola
- Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA.
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4
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Al-Mareed AA, Farah MA, Al-Anazi KM, Hailan WAQ, Ali MA. Potassium bromate-induced oxidative stress, genotoxicity and cytotoxicity in the blood and liver cells of mice. MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2022; 878:503481. [PMID: 35649675 DOI: 10.1016/j.mrgentox.2022.503481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 06/15/2023]
Abstract
Potassium bromate (KBrO3) is an oxidising agent that is extensively used as a food additive, it is also a product of cosmetic and pharmaceutical relevance. The objective of this study was to evaluate the oxidative stress, genotoxicity, and apoptosis induced by KBrO3 in an experimental animal model. To study the toxic effects and oxidative stress, different doses of KBrO3 below LD50 (The half maximal lethal dose, 50, 100 and 150 mg/kg body weight) were given intraperitoneally to the mice for multiple time periods (24, 48, and 72 h). The results showed that KBrO3 significantly induces oxidative damage by increasing the levels of reactive oxygen species (ROS) and lipid peroxidase and depleted the levels of catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) enzymes in the serum and liver. Moreover, a significant increase of chromosomal aberrations in bone marrow cells and an elevated incidence of micronuclei in the peripheral blood of mice were observed. KBrO3 induces 3 ´ -OH end double-strand DNA breaks, which was evident in liver sections of the treated mice, and increases the percentage of apoptotic cells, as observed in TUNEL assays and flow cytometry analysis. The present findings indicate that KBrO3 induces oxidative stress, genotoxicity, and cytotoxicity in a dose- and time-dependent manner in mice.
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Affiliation(s)
- Ali Abdullah Al-Mareed
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Mohammed Abul Farah
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
| | - Khalid Mashay Al-Anazi
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Waleed A Q Hailan
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - M Ajmal Ali
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
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5
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Röhl C, Batke M, Damm G, Freyberger A, Gebel T, Gundert-Remy U, Hengstler JG, Mangerich A, Matthiessen A, Partosch F, Schupp T, Wollin KM, Foth H. New aspects in deriving health-based guidance values for bromate in swimming pool water. Arch Toxicol 2022; 96:1623-1659. [PMID: 35386057 PMCID: PMC9095538 DOI: 10.1007/s00204-022-03255-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 02/17/2022] [Indexed: 11/27/2022]
Abstract
Bromate, classified as a EU CLP 1B carcinogen, is a typical by-product of the disinfection of drinking and swimming pool water. The aim of this study was (a) to provide data on the occurrence of bromate in pool water, (b) to re-evaluate the carcinogenic MOA of bromate in the light of existing data, (c) to assess the possible exposure to bromate via swimming pool water and (d) to inform the derivation of cancer risk-related bromate concentrations in swimming pool water. Measurements from monitoring analysis of 229 samples showed bromate concentrations in seawater pools up to 34 mg/L. A comprehensive non-systematic literature search was done and the quality of the studies on genotoxicity and carcinogenicity was assessed by Klimisch criteria (Klimisch et al., Regul Toxicol Pharmacol 25:1–5, 1997) and SciRAP tool (Beronius et al., J Appl Toxicol, 38:1460–1470, 2018) respectively. Benchmark dose (BMD) modeling was performed using the modeling average mode in BMDS 3.1 and PROAST 66.40, 67 and 69 (human cancer BMDL10; EFSA 2017). For exposure assessment, data from a wide range of sources were evaluated for their reliability. Different target groups (infants/toddlers, children and adults) and exposure scenarios (recreational, sport-active swimmers, top athletes) were considered for oral, inhalation and dermal exposure. Exposure was calculated according to the frequency of swimming events and duration in water. For illustration, cancer risk-related bromate concentrations in pool water were calculated for different target groups, taking into account their exposure using the hBMDL10 and a cancer risk of 1 in 100,000. Convincing evidence was obtained from a multitude of studies that bromate induces oxidative DNA damage and acts as a clastogen in vitro and in vivo. Since statistical modeling of the available genotoxicity data is compatible with both linear as well as non-linear dose–response relationships, bromate should be conservatively considered to be a non-threshold carcinogen. BMD modeling with model averaging for renal cancer studies (Kurokawa et al., J Natl. Cancer Inst, 1983 and 1986a; DeAngelo et al., Toxicol Pathol 26:587–594, 1998) resulted in a median hBMDL10 of 0.65 mg bromate/kg body weight (bw) per day. Evaluation of different age and activity groups revealed that top athletes had the highest exposure, followed by sport-active children, sport-active adults, infants and toddlers, children and adults. The predominant route of exposure was oral (73–98%) by swallowing water, followed by the dermal route (2–27%), while the inhalation route was insignificant (< 0.5%). Accepting the same risk level for all population groups resulted in different guidance values due to the large variation in exposure. For example, for an additional risk of 1 in 100,000, the bromate concentrations would range between 0.011 for top athletes, 0.015 for sport-active children and 2.1 mg/L for adults. In conclusion, the present study shows that health risks due to bromate exposure by swimming pool water cannot be excluded and that large differences in risk exist depending on the individual swimming habits and water concentrations.
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Affiliation(s)
- C Röhl
- Institute of Toxicology and Pharmacology for Natural Scientists, Christiana Albertina University Kiel, Kiel, Germany. .,Department of Environmental Health Protection, State Agency for social Services (LAsD) Schleswig-Holstein, Neumünster, Germany.
| | - M Batke
- University Emden/Leer, Emden, Germany
| | - G Damm
- Department of Hepatobiliary Surgery and Visceral Transplantation, University Hospital, Leipzig University, Leipzig, Germany
| | - A Freyberger
- Research and Development, Pharmaceuticals, RED-PCD-TOX-P&PC Clinical Pathology, Bayer AG, Wuppertal, Germany
| | - T Gebel
- Federal Institute for Occupational Safety and Health (BAuA), Dortmund, Germany
| | - U Gundert-Remy
- Institute for Clinical Pharmacology and Toxicology, Universitätsmedizin Berlin, Charité Berlin, Germany
| | - J G Hengstler
- Leibniz Research Centre for Working Environment and Human Factors (IfADo), TU Dortmund University, Dortmund, Germany
| | - A Mangerich
- Molecular Toxicology, Department of Biology, University of Konstanz, Konstanz, Germany
| | - A Matthiessen
- Central Unit for Environmental Hygiene, University Hospital Schleswig-Holstein (UKSH), Kiel, Germany
| | - F Partosch
- Department of Toxicology, Fraunhofer-Institute for Toxicology and Experimental Medicine (ITEM), Hannover, Germany
| | - T Schupp
- Department of Chemical Engineering, University of Applied Science Muenster, Steinfurt, Germany
| | - K M Wollin
- Formerly Public Health Agency of Lower Saxony, Hannover, Germany
| | - H Foth
- Institute of Environmental Toxicology, University of Halle, Halle/Saale, Germany
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6
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Klapacz J, Gollapudi BB. Considerations for the Use of Mutation as a Regulatory Endpoint in Risk Assessment. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2020; 61:84-93. [PMID: 31301246 DOI: 10.1002/em.22318] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/08/2019] [Accepted: 07/10/2019] [Indexed: 06/10/2023]
Abstract
Assessment of a chemical's potential to cause permanent changes in the genetic code has been a common practice in the industry and regulatory settings for decades. Furthermore, the genetic toxicity battery of tests has typically been employed during the earliest stages of the research and development programs of new product development. A positive outcome from such battery has a major impact on the chemical's utility, industrial hygiene, product stewardship practices, and product life cycle analysis, among many other decisions that need to be taken by the industry, even before the registration of a chemical is undertaken. Under the prevailing regulatory paradigm, the dichotomous (yes/no) evaluation of the chemical's genotoxic potential leads to a conservative, linear no-threshold (LNT) risk assessment, unless compelling and undeniable data to the contrary can be provided to satisfy regulators, typically in a number of different global jurisdictions. With the current advent of predictive methods, new testing paradigms, mode-of-action/adverse outcome pathways, and quantitative risk assessment approaches, various stakeholders are starting to employ these state-of-the-science methodologies to further the conversation on decision making and advance the regulatory paradigm beyond the dominant LNT status quo. This commentary describes these novel methodologies, relevant biological responses, and how these can affect internal and regulatory risk assessment approaches. Environ. Mol. Mutagen. 61:84-93, 2020. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Joanna Klapacz
- Toxicology and Environmental Research and Consulting, The Dow Chemical Company, Midland, Michigan
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7
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Spassova MA. Statistical Approach to Identify Threshold and Point of Departure in Dose-Response Data. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2019; 39:940-956. [PMID: 30253453 DOI: 10.1111/risa.13191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 08/09/2018] [Accepted: 08/18/2018] [Indexed: 06/08/2023]
Abstract
The study presents an integrated, rigorous statistical approach to define the likelihood of a threshold and point of departure (POD) based on dose-response data using nested family of bent-hyperbola models. The family includes four models: the full bent-hyperbola model, which allows for transition between two linear regiments with various levels of smoothness; a bent-hyperbola model reduced to a spline model, where the transition is fixed to a knot; a bent-hyperbola model with a restricted negative asymptote slope of zero, named hockey-stick with arc (HS-Arc); and spline model reduced further to a hockey-stick type model (HS), where the first linear segment has a slope of zero. A likelihood-ratio test is used to discriminate between the models and determine if the more flexible versions of the model provide better or significantly better fit than a hockey-stick type model. The full bent-hyperbola model can accommodate both threshold and nonthreshold behavior, can take on concave up and concave down shapes with various levels of curvature, can approximate the biochemically relevant Michaelis-Menten model, and even be reduced to a straight line. Therefore, with the use of this model, the presence or absence of a threshold may even become irrelevant and the best fit of the full bent-hyperbola model be used to characterize the dose-response behavior and risk levels, with no need for mode of action (MOA) information. Point of departure (POD), characterized by exposure level at which some predetermined response is reached, can be defined using the full model or one of the better fitting reduced models.
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8
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Ali BH, Za’abi MA, Karaca T, Suleimani YA, Balushi KAA, Manoj P, Ashique M, Nemmar A. Potassium bromate-induced kidney damage in rats and the effect of gum acacia thereon. Am J Transl Res 2018; 10:126-137. [PMID: 29422999 PMCID: PMC5801352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2017] [Accepted: 08/04/2017] [Indexed: 06/08/2023]
Abstract
Potassium bromate (KBrO3) is used in many countries in cosmetic and food industries. In this work, we investigated in male Sprague-Dawley rats, the effect of four graded oral doses of KBrO3 (5, 15, 45 and 135 mg/kg/day for 28 days) on renal function tests, inflammation, oxidative damage, and apoptosis, as well as on histopathology, using several traditional and novel renal injury biomarkers in plasma, urine and renal tissues. We also tested the possible ameliorative action of the renoprotective prebiotic agent gum acacia (GA) on the actions of KBrO3 when given concomitantly with it in the drinking water at a concentration of 15%w/v. Taken together, the results indicated that treatment with KBrO3 at the 45 and 135 mg/kg doses caused a significant dose-dependent nephrotoxicity, as evident by the measured renal structural and functional indices and biomarkers of toxicity. GA co-treatment significantly abated most of the indices and biomarkers of the renal toxicity caused by KBrO3, suggesting a beneficial effect and its possible inclusion in edible products where KBrO3 is still used.
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Affiliation(s)
- Badreldin H Ali
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos UniversityAl Khoudh, Oman
| | - Mohammed Al Za’abi
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos UniversityAl Khoudh, Oman
| | - Turan Karaca
- Department of Histology-Embryology, Faculty of Medicine, University of Trakya, Balkan Campus22030, Edirne, Turkey
| | - Yousuf Al Suleimani
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos UniversityAl Khoudh, Oman
| | - Khalid A Al Balushi
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos UniversityAl Khoudh, Oman
| | - Priyadarsini Manoj
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos UniversityAl Khoudh, Oman
| | - Mohammed Ashique
- Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos UniversityAl Khoudh, Oman
| | - Abderrahim Nemmar
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University17666, Al Ain, United Arab Emirates
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9
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Çağlayan M, Horton JK, Dai DP, Stefanick DF, Wilson SH. Oxidized nucleotide insertion by pol β confounds ligation during base excision repair. Nat Commun 2017; 8:14045. [PMID: 28067232 PMCID: PMC5228075 DOI: 10.1038/ncomms14045] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/23/2016] [Indexed: 01/26/2023] Open
Abstract
Oxidative stress in cells can lead to accumulation of reactive oxygen species and oxidation of DNA precursors. Oxidized purine nucleotides can be inserted into DNA during replication and repair. The main pathway for correcting oxidized bases in DNA is base excision repair (BER), and in vertebrates DNA polymerase β (pol β) provides gap filling and tailoring functions. Here we report that the DNA ligation step of BER is compromised after pol β insertion of oxidized purine nucleotides into the BER intermediate in vitro. These results suggest the possibility that BER mediated toxic strand breaks are produced in cells under oxidative stress conditions. We observe enhanced cytotoxicity in oxidizing-agent treated pol β expressing mouse fibroblasts, suggesting formation of DNA strand breaks under these treatment conditions. Increased cytotoxicity following MTH1 knockout or treatment with MTH1 inhibitor suggests the oxidation of precursor nucleotides. Oxidative stress in cells leads to the oxidations of DNA precursors. Here the authors show that these oxidized precursors can be incorporated in vivo during base excision repair, leading to DNA breaks and cytotoxicity.
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Affiliation(s)
- Melike Çağlayan
- Genome Integrity and Structural Biology Laboratory, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
| | - Julie K Horton
- Genome Integrity and Structural Biology Laboratory, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
| | - Da-Peng Dai
- Genome Integrity and Structural Biology Laboratory, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
| | - Donna F Stefanick
- Genome Integrity and Structural Biology Laboratory, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
| | - Samuel H Wilson
- Genome Integrity and Structural Biology Laboratory, National Institutes of Health, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, USA
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10
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Lippi G, Buonocore R, Tarperi C, Montagnana M, Festa L, Danese E, Benati M, Salvagno GL, Bonaguri C, Roggenbuck D, Schena F. DNA injury is acutely enhanced in response to increasing bulks of aerobic physical exercise. Clin Chim Acta 2016; 460:146-51. [PMID: 27374303 DOI: 10.1016/j.cca.2016.06.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 06/27/2016] [Accepted: 06/29/2016] [Indexed: 01/07/2023]
Abstract
The aim of this study was to evaluate DNA damage in response to increasing bulks of aerobic physical exercise. Fifteen adult and trained athletes performed four sequential trials with increasing running distance (5-, 10-, 21- and 42-km) in different periods of the year. The γ-H2AX foci parameters were analyzed before and 3h after the end of each trial. The values of all γ-H2AX foci parameters were enhanced after the end of each trial, with values gradually increasing from the 5- to the 42-km trial. Interestingly, a minor increase of γ-H2AX foci was still evident after 5- to 10-km running, but a much higher increase occurred when the running distance exceeded 21km. The generation of DNA injury was then magnified by running up to 42-km. The increase of each γ-H2AX foci parameter was then found to be associated with both running distance and average intensity. In multivariate linear regression analysis, the running distance was significantly associated with average intensity and post-run variation in the percentage of cells with γ-H2AX foci. We can hence conclude that aerobic exercise may generate an acute DNA damage in trained athletes, which is highly dependent upon running distance and average intensity.
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Affiliation(s)
- Giuseppe Lippi
- Section of Clinical Biochemistry, University of Verona, Verona, Italy.
| | - Ruggero Buonocore
- Laboratory of Clinical Chemistry and Hematology, University Hospital of Parma, Italy
| | - Cantor Tarperi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | | | - Luca Festa
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Elisa Danese
- Section of Clinical Biochemistry, University of Verona, Verona, Italy
| | - Marco Benati
- Section of Clinical Biochemistry, University of Verona, Verona, Italy
| | | | - Chiara Bonaguri
- Laboratory of Clinical Chemistry and Hematology, University Hospital of Parma, Italy
| | - Dirk Roggenbuck
- Institute of Biotechnology, Faculty 2, Brandenburg Technical University, Senftenberg, Germany and Medipan GmbH, Dahlewitz/Berlin, Germany
| | - Federico Schena
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy; Center for Research in Mountain, Sport and Health (CeRISM), Rovereto, Italy
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