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Speer RM, Yu H, Zhou X, Nandi S, Alexandrov L, Guo Y, Hudson LG, Liu KJ. Arsenic and UVR co-exposure results in unique gene expression profile identifying key co-carcinogenic mechanisms. Toxicol Appl Pharmacol 2024; 482:116773. [PMID: 38036231 PMCID: PMC10883297 DOI: 10.1016/j.taap.2023.116773] [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: 10/12/2023] [Revised: 11/22/2023] [Accepted: 11/23/2023] [Indexed: 12/02/2023]
Abstract
Changes in gene expression underlie many pathogenic endpoints including carcinogenesis. Metals, like arsenic, alter gene expression; however, the consequences of co-exposures of metals with other stressors are less understood. Although arsenic acts as a co-carcinogen by enhancing the development of UVR skin cancers, changes in gene expression in arsenic UVR co-carcinogenesis have not been investigated. We performed RNA-sequencing analysis to profile changes in gene expression distinct from arsenic or UVR exposures alone. A large number of differentially expressed genes (DEGs) were identified after arsenic exposure alone, while after UVR exposure alone fewer genes were changed. A distinct increase in the number of DEGs was identified after exposure to combined arsenic and UVR exposure that was synergistic rather than additive. In addition, a majority of these DEGs were unique from arsenic or UVR alone suggesting a distinct response to combined arsenic-UVR exposure. Globally, arsenic alone and arsenic plus UVR exposure caused a global downregulation of genes while fewer genes were upregulated. Gene Ontology analysis using the DEGs revealed cellular processes related to chromosome instability, cell cycle, cellular transformation, and signaling were targeted by combined arsenic and UVR exposure, distinct from UVR alone and arsenic alone, while others were related to epigenetic mechanisms such as the modification of histones. This result suggests the cellular functions we identified in this study may be key in understanding how arsenic enhances UVR carcinogenesis and that arsenic-enhanced gene expression changes may drive co-carcinogenesis of UVR exposure.
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Affiliation(s)
- Rachel M Speer
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, USA.
| | - Hui Yu
- Department of Internal Medicine, Division of Molecular Medicine, University of New Mexico, Albuquerque, NM, USA.
| | - Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, USA.
| | - Shuvro Nandi
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, UC San Diego, La Jolla, CA 92093, USA; Moores Cancer Center, UC San Diego, La Jolla, CA 92037, USA.
| | - Ludmil Alexandrov
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, UC San Diego, La Jolla, CA 92093, USA; Moores Cancer Center, UC San Diego, La Jolla, CA 92037, USA.
| | - Yan Guo
- Department of Internal Medicine, Division of Molecular Medicine, University of New Mexico, Albuquerque, NM, USA.
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, USA.
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, USA; Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA; Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794, USA.
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Speer RM, Nandi SP, Cooper KL, Zhou X, Yu H, Guo Y, Hudson LG, Alexandrov LB, Liu KJ. Arsenic is a potent co-mutagen of ultraviolet light. Commun Biol 2023; 6:1273. [PMID: 38104187 PMCID: PMC10725444 DOI: 10.1038/s42003-023-05659-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 12/01/2023] [Indexed: 12/19/2023] Open
Abstract
Arsenic enhances the carcinogenicity of ultraviolet radiation (UVR). However, the mechanisms of arsenic-driven oncogenesis are not well understood. Here, we utilize experimental systems to investigate the carcinogenic and mutagenic properties of co-exposure to arsenic and UVR. In vitro and in vivo exposures indicate that, by itself, arsenic is not mutagenic. However, in combination with UVR, arsenic exposure has a synergistic effect leading to an accelerated mouse skin carcinogenesis and to more than 2-fold enrichment of UVR mutational burden. Notably, mutational signature ID13, previously found only in UVR-associated human skin cancers, is observed exclusively in mouse skin tumors and cell lines jointly exposed to arsenic and UVR. This signature was not observed in any model system exposed purely to arsenic or purely to UVR, making ID13, to the best of our knowledge, the first co-exposure signature to be reported using controlled experimental conditions. Analysis of existing skin cancer genomics data reveals that only a subset of cancers harbor ID13 and these exhibit an elevated UVR mutagenesis. Our results report a unique mutational signature caused by a co-exposure to two environmental carcinogens and provide comprehensive evidence that arsenic is a potent co-mutagen and co-carcinogen of UVR.
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Affiliation(s)
- Rachel M Speer
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, 87106, USA
| | - Shuvro P Nandi
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA, 92093, USA
- Moores Cancer Center, UC San Diego, La Jolla, CA, 92037, USA
- Department of Bioengineering, UC San Diego, La Jolla, CA, 92093, USA
| | - Karen L Cooper
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, 87106, USA
| | - Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, 87106, USA
| | - Hui Yu
- Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, 33136, USA
| | - Yan Guo
- Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, 33136, USA
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, 87106, USA
| | - Ludmil B Alexandrov
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA, 92093, USA.
- Moores Cancer Center, UC San Diego, La Jolla, CA, 92037, USA.
- Department of Bioengineering, UC San Diego, La Jolla, CA, 92093, USA.
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM, 87106, USA.
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY, 11794, USA.
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY, 11794, USA.
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Wysocki R, Rodrigues JI, Litwin I, Tamás MJ. Mechanisms of genotoxicity and proteotoxicity induced by the metalloids arsenic and antimony. Cell Mol Life Sci 2023; 80:342. [PMID: 37904059 PMCID: PMC10616229 DOI: 10.1007/s00018-023-04992-5] [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: 06/23/2023] [Revised: 09/12/2023] [Accepted: 09/29/2023] [Indexed: 11/01/2023]
Abstract
Arsenic and antimony are metalloids with profound effects on biological systems and human health. Both elements are toxic to cells and organisms, and exposure is associated with several pathological conditions including cancer and neurodegenerative disorders. At the same time, arsenic- and antimony-containing compounds are used in the treatment of multiple diseases. Although these metalloids can both cause and cure disease, their modes of molecular action are incompletely understood. The past decades have seen major advances in our understanding of arsenic and antimony toxicity, emphasizing genotoxicity and proteotoxicity as key contributors to pathogenesis. In this review, we highlight mechanisms by which arsenic and antimony cause toxicity, focusing on their genotoxic and proteotoxic effects. The mechanisms used by cells to maintain proteostasis during metalloid exposure are also described. Furthermore, we address how metalloid-induced proteotoxicity may promote neurodegenerative disease and how genotoxicity and proteotoxicity may be interrelated and together contribute to proteinopathies. A deeper understanding of cellular toxicity and response mechanisms and their links to pathogenesis may promote the development of strategies for both disease prevention and treatment.
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Affiliation(s)
- Robert Wysocki
- Department of Genetics and Cell Physiology, Faculty of Biological Sciences, University of Wroclaw, 50-328, Wroclaw, Poland.
| | - Joana I Rodrigues
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 405 30, Göteborg, Sweden
| | - Ireneusz Litwin
- Academic Excellence Hub - Research Centre for DNA Repair and Replication, Faculty of Biological Sciences, University of Wroclaw, 50-328, Wroclaw, Poland
| | - Markus J Tamás
- Department of Chemistry and Molecular Biology, University of Gothenburg, Box 462, 405 30, Göteborg, Sweden.
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Speer RM, Nandi SP, Cooper KL, Zhou X, Yu H, Guo Y, Hudson LG, Alexandrov LB, Liu KJ. Arsenic is a potent co-mutagen of ultraviolet light. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.22.529578. [PMID: 36865271 PMCID: PMC9980120 DOI: 10.1101/2023.02.22.529578] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Environmental co-exposures are widespread and are major contributors to carcinogenic mechanisms. Two well-established environmental agents causing skin cancer are ultraviolet radiation (UVR) and arsenic. Arsenic is a known co-carcinogen that enhances UVR's carcinogenicity. However, the mechanisms of arsenic co-carcinogenesis are not well understood. In this study, we utilized primary human keratinocytes and a hairless mouse model to investigate the carcinogenic and mutagenic properties of co-exposure to arsenic and UVR. In vitro and in vivo exposures revealed that, on its own, arsenic is neither mutagenic nor carcinogenic. However, in combination with UVR, arsenic exposure has a synergistic effect leading to an accelerated mouse skin carcinogenesis as well as to more than 2-fold enrichment of UVR mutational burden. Notably, mutational signature ID13, previously found only in UVR-associated human skin cancers, was observed exclusively in mouse skin tumors and cell lines jointly exposed to arsenic and UVR. This signature was not observed in any model system exposed purely to arsenic or purely to UVR, making ID13 the first co-exposure signature to be reported using controlled experimental conditions. Analysis of existing genomics data from basal cell carcinomas and melanomas revealed that only a subset of human skin cancers harbor ID13 and, consistent with our experimental observations, these cancers exhibited an elevated UVR mutagenesis. Our results provide the first report of a unique mutational signature caused by a co-exposure to two environmental carcinogens and the first comprehensive evidence that arsenic is a potent co-mutagen and co-carcinogen of UVR. Importantly, our findings suggest that a large proportion of human skin cancers are not formed purely due to UVR exposure but rather due to a co-exposure of UVR and other co-mutagens such as arsenic.
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Affiliation(s)
- Rachel M. Speer
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87106, USA
| | - Shuvro P. Nandi
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA, 92093, USA
- Moores Cancer Center, UC San Diego, La Jolla, CA, 92037, USA
| | - Karen L. Cooper
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87106, USA
| | - Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87106, USA
| | - Hui Yu
- Department of Internal Medicine, Division of Molecular Medicine, University of New Mexico, Albuquerque, NM 87106, USA
| | - Yan Guo
- Department of Internal Medicine, Division of Molecular Medicine, University of New Mexico, Albuquerque, NM 87106, USA
| | - Laurie G. Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87106, USA
| | - Ludmil B. Alexandrov
- Department of Cellular and Molecular Medicine, UC San Diego, La Jolla, CA, 92093, USA
- Moores Cancer Center, UC San Diego, La Jolla, CA, 92037, USA
- Department of Bioengineering, UC San Diego, La Jolla, CA, 92093, USA
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87106, USA
- Stony Brook Cancer Center, Stony Brook University, Stony Brook NY 11794, USA
- Department of Pathology, Stony Brook University School of Medicine, Stony Brook, NY 11794, USA
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Che H, Yan S, Nie Y, Tian X, Li Y. Film-based fluorescent sensor for visual monitoring and efficient removal of aniline in solutions and gas phase. JOURNAL OF HAZARDOUS MATERIALS 2022; 435:129016. [PMID: 35500347 DOI: 10.1016/j.jhazmat.2022.129016] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/21/2022] [Accepted: 04/24/2022] [Indexed: 06/14/2023]
Abstract
Aniline has attracted much concern for its long degradation half-life and huge toxicity to the environment and human beings. Therefore, the development of a multi-functional device for visual detection and efficient removal of aniline was highly anticipated. In our work, the small-size Eu@UiO-66(COOH) was obtained by post-synthesis modification (PSM), and then the film-based fluorescent sensor was prepared by crosslinking reaction. The films not only showed incredible mechanical stability and potential for large-scale preparation, but also have excellent fluorescence response to aniline in solutions and gas phase. As the concentration of aniline increased, the fluorescence of films gradually increased at 350 nm, while the fluorescence gradually quenching at 620 nm, and the detection limits (LOD) of aniline in water and air were 0.27 ppb and 0.086 ppb, respectively. In addition, the adsorption performance of the film for aniline has also been confirmed and the maximum adsorption capacity was 32.6 mg/g, which is a strong guarantee for the realization of ultra-trace detection and toxicity reduction of aniline. In summary, the multi-functional film sensor has been designed for ultra-trace detection and efficient removal of aniline in solutions and gas phase, and have significant value for pollutant treatment, ecological restoration and early prevention.
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Affiliation(s)
- Huachao Che
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, PR China
| | - Shulin Yan
- Wuxi Little Swan Electric Co., Ltd., No. 18 South Changjiang RD, National High-tech Development Zone, Wuxi, PR China
| | - Yulun Nie
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, PR China.
| | - Xike Tian
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, PR China
| | - Yong Li
- Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, PR China
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6
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Volatier T, Schumacher B, Cursiefen C, Notara M. UV Protection in the Cornea: Failure and Rescue. BIOLOGY 2022; 11:biology11020278. [PMID: 35205145 PMCID: PMC8868636 DOI: 10.3390/biology11020278] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 01/28/2022] [Accepted: 01/28/2022] [Indexed: 01/07/2023]
Abstract
Simple Summary The sun is a deadly laser, and its damaging rays harm exposed tissues such as our skin and eyes. The skin’s protection and repair mechanisms are well understood and utilized in therapeutic approaches while the eye lacks such complete understanding of its defenses and therefore often lacks therapeutic support in most cases. The aim here was to document the similarities and differences between the two tissues as well as understand where current research stands on ocular, particularly corneal, ultraviolet protection. The objective is to identify what mechanisms may be best suited for future investigation and valuable therapeutic approaches. Abstract Ultraviolet (UV) irradiation induces DNA lesions in all directly exposed tissues. In the human body, two tissues are chronically exposed to UV: the skin and the cornea. The most frequent UV-induced DNA lesions are cyclobutane pyrimidine dimers (CPDs) that can lead to apoptosis or induce tumorigenesis. Lacking the protective pigmentation of the skin, the transparent cornea is particularly dependent on nucleotide excision repair (NER) to remove UV-induced DNA lesions. The DNA damage response also triggers intracellular autophagy mechanisms to remove damaged material in the cornea; these mechanisms are poorly understood despite their noted involvement in UV-related diseases. Therapeutic solutions involving xenogenic DNA-repair enzymes such as T4 endonuclease V or photolyases exist and are widely distributed for dermatological use. The corneal field lacks a similar set of tools to address DNA-lesions in photovulnerable patients, such as those with genetic disorders or recently transplanted tissue.
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Affiliation(s)
- Thomas Volatier
- Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 62, 50937 Cologne, Germany; (C.C.); (M.N.)
- Correspondence:
| | - Björn Schumacher
- Cologne Excellence Cluster for Cellular Stress Responses, Aging-Associated Diseases (CECAD) and Center for Molecular Medicine (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany;
| | - Claus Cursiefen
- Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 62, 50937 Cologne, Germany; (C.C.); (M.N.)
- Center for Molecular Medicine Cologne (CMMC), Faculty of Medicine and University Hospital Cologne, University of Cologne, 21, 50931 Cologne, Germany
| | - Maria Notara
- Department of Ophthalmology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 62, 50937 Cologne, Germany; (C.C.); (M.N.)
- Cologne Excellence Cluster for Cellular Stress Responses, Aging-Associated Diseases (CECAD) and Center for Molecular Medicine (CMMC), University of Cologne, Joseph-Stelzmann-Strasse 26, 50931 Cologne, Germany;
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7
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Cooper KL, Volk LB, Dominguez DR, Duran AD, Ke Jian Liu KJ, Hudson LG. Contribution of NADPH oxidase to the retention of UVR-induced DNA damage by arsenic. Toxicol Appl Pharmacol 2022; 434:115799. [PMID: 34798142 PMCID: PMC10115133 DOI: 10.1016/j.taap.2021.115799] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/16/2022]
Abstract
Arsenic is a naturally occurring element present in food, soil and water and human exposure is associated with increased cancer risk. Arsenic inhibits DNA repair at low, non-cytotoxic concentrations and amplifies the mutagenic and carcinogenic impact of other DNA-damaging agents, such as ultraviolet radiation (UVR). Arsenic exposure leads to oxidation of zinc coordinating cysteine residues, zinc loss and decreased activity of the DNA repair protein poly(ADP)ribose polymerase (PARP)-1. Because arsenic stimulates NADPH oxidase (NOX) activity leading to generation of reactive oxygen species (ROS), the goal of this study was to investigate the role of NOX in arsenic-induced inhibition of PARP activity and retention of DNA damage. NOX involvement in the arsenic response was assessed in vitro and in vivo. Keratinocytes were treated with or without arsenite, solar-simulated UVR, NOX inhibitors and/or isoform specific NOX siRNA. Knockdown or inhibition of NOX decreased arsenite-induced ROS, PARP-1 oxidation and DNA damage retention, while restoring arsenite inhibition of PARP-1 activity. The NOX2 isoform was determined to be the major contributor to arsenite-induced ROS generation and DNA damage retention. In vivo DNA damage was measured by immunohistochemical staining and analysis of dorsal epidermis sections from C57BI/6 and p91phox knockout (NOX2-/-) mice. There was no significant difference in solar-simulated UVR DNA damage as detected by percent PH2AX positive cells within NOX2-/- mice versus control. In contrast, arsenite-dependent retention of UVR-induced DNA damage was markedly reduced. Altogether, the in vitro and in vivo findings indicate that NOX is involved in arsenic enhancement of UVR-induced DNA damage.
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Affiliation(s)
- Karen L Cooper
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, 1 University of New Mexico, Albuquerque, NM 87131, United States of America
| | - Lindsay B Volk
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, 1 University of New Mexico, Albuquerque, NM 87131, United States of America
| | - Dayna R Dominguez
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, 1 University of New Mexico, Albuquerque, NM 87131, United States of America
| | - Antonia D Duran
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, 1 University of New Mexico, Albuquerque, NM 87131, United States of America; Department of Chemistry and Biochemistry, Ohio State University, Columbus, OH 43210, United States of America
| | - K J Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, 1 University of New Mexico, Albuquerque, NM 87131, United States of America
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, 1 University of New Mexico, Albuquerque, NM 87131, United States of America.
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8
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Zhou X, Speer RM, Volk L, Hudson LG, Liu KJ. Arsenic co-carcinogenesis: Inhibition of DNA repair and interaction with zinc finger proteins. Semin Cancer Biol 2021; 76:86-98. [PMID: 33984503 PMCID: PMC8578584 DOI: 10.1016/j.semcancer.2021.05.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/05/2021] [Accepted: 05/06/2021] [Indexed: 12/17/2022]
Abstract
Arsenic is widely present in the environment and is associated with various population health risks including cancers. Arsenic exposure at environmentally relevant levels enhances the mutagenic effect of other carcinogens such as ultraviolet radiation. Investigation on the molecular mechanisms could inform the prevention and intervention strategies of arsenic carcinogenesis and co-carcinogenesis. Arsenic inhibition of DNA repair has been demonstrated to be an important mechanism, and certain DNA repair proteins have been identified to be extremely sensitive to arsenic exposure. This review will summarize the recent advances in understanding the mechanisms of arsenic carcinogenesis and co-carcinogenesis, including DNA damage induction and ROS generation, particularly how arsenic inhibits DNA repair through an integrated molecular mechanism which includes its interactions with sensitive zinc finger DNA repair proteins.
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Affiliation(s)
- Xixi Zhou
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Rachel M Speer
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Lindsay Volk
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA.
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, University of New Mexico Health Sciences Center, Albuquerque, NM, 87131, USA.
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9
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Li Z, Liu Y, Wang F, Gao Z, Elhefny MA, Habotta OA, Abdel Moneim AE, Kassab RB. Neuroprotective effects of protocatechuic acid on sodium arsenate induced toxicity in mice: Role of oxidative stress, inflammation, and apoptosis. Chem Biol Interact 2021; 337:109392. [PMID: 33497687 DOI: 10.1016/j.cbi.2021.109392] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 01/01/2021] [Accepted: 01/19/2021] [Indexed: 12/17/2022]
Abstract
Arsenic is a toxic metalloid abundantly found in nature and used in many industries. Consumption of contaminated water mainly results in human exposure to arsenic. Toxicity (arsenicosis) resulting from arsenic exposure causes cerebral neurodegeneration. Protocatechuic acid (PCA), a phenol derived from edible plants, has antioxidant properties. The present study investigated the neuroprotective potential of PCA against arsenic-induced neurotoxicity in mice. Male Swiss albino mice were divided into four groups: (i) orally administered physiological saline, (ii) orally administered 100 mg/kg PCA, (iii) orally administered 5 mg/kg NaAsO2, and (iv) orally administered 100 mg/kg PCA 120 min prior to oral administration of 5 mg/kg NaAsO2. Each group received its respective treatment for 1 week, after which cortical tissues from each group were analyzed for various parameters of oxidative stress, proinflammatory cytokines, apoptosis-related proteins, and changes in histopathology. NaAsO2-treatment resulted in a significant increase in lipid peroxidation (LPO), inducible nitric oxide synthetase (iNOs), and NO levels, with a decrease in the levels of both enzymatic (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) and non-enzymatic (glutathione) antioxidant markers. Arsenic increased proinflammatory cytokine (tumor necrosis factor-α and interleukin-1β) levels, enhanced caspase-3 and Bax expression, and reduced Bcl-2 expression. Furthermore, arsenic-exposure in mice decreased significantly acetylcholinesterase activity and brain-derived neurotrophic factor level in the cerebral cortex. Histopathological examination revealed changes in nerve cell cyto-architecture and distribution in arsenic-exposed brain tissue sections. PCA treatment before arsenic administration resulted in a positive shift in the oxidative stress and cytokine levels with decreased levels of LPO, iNOS, and NO. PCA pre-treatment considerably attenuated arsenic-associated histopathological changes in murine brain tissue. This study suggested that the presence of PCA may be responsible for the prevention of arsenic-induced neurotoxicity.
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Affiliation(s)
- Zhaoxia Li
- Department of Pediatric, The Second Hospital, Cheeloo College of Medicine, Shandong University, No. 247 Beiyuan Street, Jinan, Shandong, 250033, People's Republic of China
| | - Yujuan Liu
- Department of Pediatric, Binzhou People's Hospital, Binzhou, Shandong Province, 256600, China
| | - Fang Wang
- Department of Pediatric, Binzhou People's Hospital, Binzhou, Shandong Province, 256600, China
| | - Zhuanglei Gao
- Department of Gastrointestinal Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, No. 247 Beiyuan Street, Jinan, Shandong, 250033, People's Republic of China.
| | - Mohamed A Elhefny
- Department of Cancer and Molecular Biology, National Cancer Institute, Cairo University, Cairo, Egypt; Department of Medial Genetics, Faculty of Medicine; Umm Al-Qura University, Alqunfudah, Saudi Arabia
| | - Ola A Habotta
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Mansoura University, Mansoura, Egypt
| | - Ahmed E Abdel Moneim
- Department of Zoology and Entomology, Faculty of Science, Helwan University, 11795, Egypt
| | - Rami B Kassab
- Department of Zoology and Entomology, Faculty of Science, Helwan University, 11795, Egypt; Biology Department, Faculty of Science and Arts, Al Baha University, Almakhwah Branch, Saudi Arabia
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Peroxynitrite contributes to arsenic-induced PARP-1 inhibition through ROS/RNS generation. Toxicol Appl Pharmacol 2019; 378:114602. [PMID: 31152818 DOI: 10.1016/j.taap.2019.114602] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 05/22/2019] [Accepted: 05/28/2019] [Indexed: 01/14/2023]
Abstract
Arsenic, in the trivalent form (AsIII), is a human co-carcinogen reported to enhance mutagenesis effects of other carcinogens such as UV radiation by inhibiting DNA repair. The zinc finger DNA repair protein Poly (ADP-ribose) polymerase 1 (PARP-1) is a sensitive target of AsIII and both reactive oxygen and nitrogen species (ROS/RNS) generated by AsIII contribute to PARP-1 inhibition. However, the mechanisms of ROS/RNS-mediated PARP inhibition and how AsIII-generated ROS/RNS may be interconnected are still unclear. In this study, we found AsIII exposure of normal human keratinocyte (HEKn) cells generated peroxynitrite through superoxide and nitric oxide production in an AsIII concentration dependent manner. Peroxynitrite inhibited PARP-1 activity and caused zinc loss from PARP-1 protein while scavenging peroxynitrite was protective of the impacts on PARP-1. We identified peroxynitrite was responsible for S-nitrosation on cysteine residues resulting in PARP-1 zinc finger conformational changes. Taken together, the evidence indicates AsIII generates peroxynitrite through superoxide and nitric oxide production, induces S-nitrosation on PARP-1, leading to zinc loss and activity inhibition of PARP-1, thus enhancing DNA damage caused by UV radiation. These findings highlight a role for peroxynitrite as a key molecule of ROS/RNS mediated DNA repair inhibition by AsIII which should inform the development of prevention and intervention strategies against AsIII co-carcinogenesis.
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Zhou X, Cooper KL, Huestis J, Xu H, Burchiel SW, Hudson LG, Liu KJ. S-nitrosation on zinc finger motif of PARP-1 as a mechanism of DNA repair inhibition by arsenite. Oncotarget 2018; 7:80482-80492. [PMID: 27741521 PMCID: PMC5348335 DOI: 10.18632/oncotarget.12613] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 10/04/2016] [Indexed: 12/21/2022] Open
Abstract
Arsenic, a widely distributed carcinogen, is known to significantly amplify the impact of other carcinogens through inhibition of DNA repair. Our recent work suggests that reactive oxygen/nitrogen species (ROS/RNS) induced by arsenite (AsIII) play an important role in the inhibition of the DNA repair protein Poly(ADP-ribose) polymerase 1 (PARP-1). AsIII-induced ROS lead to oxidation of cysteine residues within the PARP-1 zinc finger DNA binding domain. However, the mechanism underlying RNS-mediated PARP inhibition by arsenic remains unknown. In this work, we demonstrate that AsIII treatment of normal human keratinocyte (HEKn) cells induced S-nitrosation on cysteine residues of PARP-1 protein, in a similar manner to a nitric oxide donor. S-nitrosation of PARP-1 could be reduced by 1400W (inducible nitric oxide synthase inhibitor) or c-PTIO (a nitric oxide scavenger). Furthermore, AsIII treatment of HEKn cells leads to zinc loss and inhibition of PARP-1 enzymatic activity. AsIII and 1400W/c-PTIO co-treatment demonstrate that these effects occur in an iNOS- and NO-dependent manner. Importantly, we confirmed S-nitrosation on the zinc finger DNA binding domain of PARP-1 protein. Taken together, AsIII induces S-nitrosation on PARP-1 zinc finger DNA binding domain by generating NO through iNOS activation, leading to zinc loss and inhibition of PARP-1 activity, thereby increasing retention of damaged DNA. These findings identify S-nitrosation as an important component of the molecular mechanism underlying AsIII inhibition of DNA repair, which may benefit the development of preventive and intervention strategies against AsIII co-carcinogenesis.
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Affiliation(s)
- Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Karen L Cooper
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Juliana Huestis
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Huan Xu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Scott W Burchiel
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
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12
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Ding X, Zhou X, Cooper KL, Huestis J, Hudson LG, Liu KJ. Differential sensitivities of cellular XPA and PARP-1 to arsenite inhibition and zinc rescue. Toxicol Appl Pharmacol 2017; 331:108-115. [PMID: 28552776 DOI: 10.1016/j.taap.2017.05.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 05/18/2017] [Accepted: 05/24/2017] [Indexed: 12/20/2022]
Abstract
Arsenite directly binds to the zinc finger domains of the DNA repair protein poly (ADP ribose) polymerase (PARP)-1, and inhibits PARP-1 activity in the base excision repair (BER) pathway. PARP inhibition by arsenite enhances ultraviolet radiation (UVR)-induced DNA damage in keratinocytes, and the increase in DNA damage is reduced by zinc supplementation. However, little is known about the effects of arsenite and zinc on the zinc finger nucleotide excision repair (NER) protein xeroderma pigmentosum group A (XPA). In this study, we investigated the difference in response to arsenite exposure between XPA and PARP-1, and the differential effectiveness of zinc supplementation in restoring protein DNA binding and DNA damage repair. Arsenite targeted both XPA and PARP-1 in human keratinocytes, resulting in zinc loss from each protein and a pronounced decrease in XPA and PARP-1 binding to chromatin as demonstrated by Chip-on-Western assays. Zinc effectively restored DNA binding of PARP-1 and XPA to chromatin when zinc concentrations were equal to those of arsenite. In contrast, zinc was more effective in rescuing arsenite-augmented direct UVR-induced DNA damage than oxidative DNA damage. Taken together, our findings indicate that arsenite interferes with PARP-1 and XPA binding to chromatin, and that zinc supplementation fully restores DNA binding activity to both proteins in the cellular context. Interestingly, rescue of arsenite-inhibited DNA damage repair by supplemental zinc was more sensitive for DNA damage repaired by the XPA-associated NER pathway than for the PARP-1-dependent BER pathway. This study expands our understanding of arsenite's role in DNA repair inhibition and co-carcinogenesis.
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Affiliation(s)
- Xiaofeng Ding
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131, United States; College of Life Science, Hunan Normal University, Changsha, Hunan 410081, China
| | - Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131, United States
| | - Karen L Cooper
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131, United States
| | - Juliana Huestis
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131, United States
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131, United States.
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131, United States
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13
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Tsai CW, Yang MD, Hsia TC, Chang WS, Hsu CM, Hsieh YH, Chung JG, Bau DT. Dithiothreitol enhanced arsenic-trioxide-induced cell apoptosis in cultured oral cancer cells via mitochondrial dysfunction and endoplasmic reticulum stress. ENVIRONMENTAL TOXICOLOGY 2017; 32:17-27. [PMID: 26494474 DOI: 10.1002/tox.22208] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 10/02/2015] [Accepted: 10/04/2015] [Indexed: 06/05/2023]
Abstract
Arsenic is naturally occurring toxic metalloid and drinking As2 O3 containing water are recognized to be related to increased risk of neurotoxicity, liver injury, blackfoot disease, hypertension, and cancer. On the contrary, As2 O3 has been an ancient drug used in traditional Chinese medicine with substantial anticancer activities, especially in the treatment of acute promyelocytic leukemia as well as chronic wound healing. However, the cytotoxicity and detail mechanisms of As2 O3 action in solid cancer cells, such as oral cancer cells, are largely unknown. In this study, we have primarily cultured four pairs of tumor and nontumor cells from the oral cancer patients and treated the cells with As2 O3 alone or combined with dithiothreitol (DTT). The results showed that 0.5 μM As2 O3 plus 20 μM DTT caused a significant cell death of oral cancer cells but not the nontumor cells. Also As2 O3 plus DTT upregulated Bax and Bak, downregulated Bcl-2 and p53, caused a loss of mitochondria membrane potential in oral cancer cells. On the other way, As2 O3 also triggered endoplasmic reticulum stress and increased the levels of glucose-regulated protein 78, calpain 1 and 2. Our results suggest that DTT could synergistically enhance the effects of As2 O3 on killing oral cancer cells while nontoxic to the nontumor cells. The combination is promising for clinical practice in oral cancer therapy and worth further investigations. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 17-27, 2017.
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Affiliation(s)
- Chia-Wen Tsai
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
| | - Mei-Due Yang
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
- Department of Clinical Nutrition, China Medical University Hospital, Taichung, Taiwan
| | - Te-Chun Hsia
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
- Department of Intensive Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Wen-Shin Chang
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
- Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan
| | - Chin-Mu Hsu
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
| | - Yi-Hsien Hsieh
- Institution of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan
| | - Jing-Gung Chung
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
- Department of Biotechnology, Asia University, Taichung, Taiwan
| | - Da-Tian Bau
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan
- Graduate Institute of Clinical Medical Science, China Medical University, Taichung, Taiwan
- Department of Bioinformatics and Medical Engineering, Asia University, Taichung, Taiwan
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Huestis J, Zhou X, Chen L, Feng C, Hudson LG, Liu KJ. Kinetics and thermodynamics of zinc(II) and arsenic(III) binding to XPA and PARP-1 zinc finger peptides. J Inorg Biochem 2016; 163:45-52. [PMID: 27521476 PMCID: PMC5096954 DOI: 10.1016/j.jinorgbio.2016.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 07/29/2016] [Accepted: 08/01/2016] [Indexed: 12/18/2022]
Abstract
Inhibition of DNA repair is an established mechanism of arsenic co-carcinogenesis, and may be perpetuated by the binding of As(III) to key zinc finger (zf) DNA repair proteins. Validated molecular targets of As(III) include the first zinc finger domain of Poly (ADP-Ribose) Polymerase 1 (PARP-1), and the zinc finger domain of Xeroderma Pigmentosum Complementation Group A (XPA). In order to gain an understanding of the thermodynamic and kinetic parameters of the interaction of As(III) with these two zinc finger motifs, a fluorescence based approach was used to investigate Zn(II) and As(III) binding to synthetic model peptides corresponding to the zf motif of XPA and first zf motif of PARP-1, referred to in this paper as XPAzf and PARP-1zf-1, respectively. While XPAzf and PARP-1zf-1 display similar relative affinities for As(III), PARP-1zf-1 shows a potential kinetic advantage over XPAzf for As(III) binding, with a rate constant for the fast phase of formation of As(III)-PARP-1zf-1 approximately 4-fold higher than for As(III)-XPAzf. However, the binding of Zn(II) with either peptide proceeds at a faster rate than As(III). Notably, XPAzf demonstrates comparable affinities for binding both metals, while PARP-1zf-1 shows a slightly higher affinity for Zn(II), suggesting that the relative concentrations of Zn(II) and As(III) in a system may significantly influence which species predominates in zinc finger occupancy. These results provide insight into the mechanisms underlying interactions between zinc finger structures and As(III), and highlight the potential utility of zinc supplementation in mitigating adverse effects of As(III) on zinc finger functions in vivo.
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Affiliation(s)
- Juliana Huestis
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Li Chen
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Changjian Feng
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Laurie G Hudson
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
| | - Ke Jian Liu
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA.
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15
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Yager JW, Erdei E, Myers O, Siegel M, Berwick M. Arsenic and ultraviolet radiation exposure: melanoma in a New Mexico non-Hispanic white population. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2016; 38:897-910. [PMID: 26445994 PMCID: PMC8164524 DOI: 10.1007/s10653-015-9770-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 09/23/2015] [Indexed: 05/21/2023]
Abstract
Cases of cutaneous melanoma and controls were enrolled in a New Mexico population-based study; subjects were administered questionnaires concerning ultraviolet (UV) and inorganic arsenic (iAs) exposure. Historical iAs exposure was estimated. UV exposure estimates were also derived using geospatial methods. Drinking water samples were collected for iAs analysis. Blood samples were collected for DNA repair (Comet) and DNA repair gene polymorphism assays. Arsenic concentrations were determined in urine and toenail samples. UV exposures during the previous 90 days did not vary significantly between cases and controls. Mean (±SD) current home iAs drinking water was not significantly different for cases and controls [3.98 μg/L (±3.67) vs. 3.47 μg/L (±2.40)]. iAs exposure showed no effect on DNA repair or association with melanoma. Results did not corroborate a previously reported association between toenail As and melanoma risk. Arsenic biomarkers in urine and toenail were highly significantly correlated with iAs in drinking water. A UV-DNA repair interaction for UV exposure over the previous 7-90 days was shown; cases had higher DNA damage than controls at low UV values. This novel finding suggests that melanoma cases may be more sensitive to low-level UV exposure than are controls. A UV-APEX1 interaction was shown. Subjects with the homozygous rare APEX1 DNA repair gene allele had a higher risk of early melanoma diagnosis at low UV exposure compared with those with the homozygous wild type or the heterozygote. Notably, a UV-arsenic interaction on inhibition of DNA repair was not observed at iAs drinking water concentrations below 10 ppb (μg/L).
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Affiliation(s)
- Janice W Yager
- Division of Epidemiology, Biostatistics and Preventive Medicine, Health Sciences Center, Department of Internal Medicine, University of New Mexico, Albuquerque, NM, USA.
- ENVIRON International Corporation, 2200 Powell Street, Suite 700, Emeryville, CA, 94608, USA.
| | - Esther Erdei
- Division of Epidemiology, Biostatistics and Preventive Medicine, Health Sciences Center, Department of Internal Medicine, University of New Mexico, Albuquerque, NM, USA
- Department of Family and Community Medicine, University of New Mexico, Albuquerque, NM, USA
| | - Orrin Myers
- Division of Epidemiology, Biostatistics and Preventive Medicine, Health Sciences Center, Department of Internal Medicine, University of New Mexico, Albuquerque, NM, USA
| | - Malcolm Siegel
- Division of Epidemiology, Biostatistics and Preventive Medicine, Health Sciences Center, Department of Internal Medicine, University of New Mexico, Albuquerque, NM, USA
| | - Marianne Berwick
- Division of Epidemiology, Biostatistics and Preventive Medicine, Health Sciences Center, Department of Internal Medicine, University of New Mexico, Albuquerque, NM, USA
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16
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Thompson BC, Halliday GM, Damian DL. Nicotinamide enhances repair of arsenic and ultraviolet radiation-induced DNA damage in HaCaT keratinocytes and ex vivo human skin. PLoS One 2015; 10:e0117491. [PMID: 25658450 PMCID: PMC4319842 DOI: 10.1371/journal.pone.0117491] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 12/25/2014] [Indexed: 12/14/2022] Open
Abstract
Arsenic-induced skin cancer is a significant global health burden. In areas with arsenic contamination of water sources, such as China, Pakistan, Myanmar, Cambodia and especially Bangladesh and West Bengal, large populations are at risk of arsenic-induced skin cancer. Arsenic acts as a co-carcinogen with ultraviolet (UV) radiation and affects DNA damage and repair. Nicotinamide (vitamin B3) reduces premalignant keratoses in sun-damaged skin, likely by prevention of UV-induced cellular energy depletion and enhancement of DNA repair. We investigated whether nicotinamide modifies DNA repair following exposure to UV radiation and sodium arsenite. HaCaT keratinocytes and ex vivo human skin were exposed to 2μM sodium arsenite and low dose (2J/cm2) solar-simulated UV, with and without nicotinamide supplementation. DNA photolesions in the form of 8-oxo-7,8-dihydro-2′-deoxyguanosine and cyclobutane pyrimidine dimers were detected by immunofluorescence. Arsenic exposure significantly increased levels of 8-oxo-7,8-dihydro-2′-deoxyguanosine in irradiated cells. Nicotinamide reduced both types of photolesions in HaCaT keratinocytes and in ex vivo human skin, likely by enhancing DNA repair. These results demonstrate a reduction of two different photolesions over time in two different models in UV and arsenic exposed cells. Nicotinamide is a nontoxic, inexpensive agent with potential for chemoprevention of arsenic induced skin cancer.
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Affiliation(s)
- Benjamin C. Thompson
- Department of Dermatology, Sydney Cancer Centre, Bosch Institute, University of Sydney at Royal Prince Alfred Hospital, Camperdown, Sydney
| | - Gary M. Halliday
- Department of Dermatology, Sydney Cancer Centre, Bosch Institute, University of Sydney at Royal Prince Alfred Hospital, Camperdown, Sydney
| | - Diona L. Damian
- Department of Dermatology, Sydney Cancer Centre, Bosch Institute, University of Sydney at Royal Prince Alfred Hospital, Camperdown, Sydney
- Melanoma Institute Australia, North Sydney, Australia
- * E-mail:
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17
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Melanocytes and keratinocytes have distinct and shared responses to ultraviolet radiation and arsenic. Toxicol Lett 2013; 224:407-15. [PMID: 24270004 DOI: 10.1016/j.toxlet.2013.11.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 11/11/2013] [Accepted: 11/12/2013] [Indexed: 12/14/2022]
Abstract
The rise of melanoma incidence in the United States is a growing public health concern. A limited number of epidemiology studies suggest an association between arsenic levels and melanoma risk. Arsenic acts as a co-carcinogen with ultraviolet radiation (UVR) for the development of squamous cell carcinoma and proposed mechanisms include generation of oxidative stress by arsenic and UVR and inhibition of UVR-induced DNA repair by arsenic. In this study, we investigate similarities and differences in response to arsenic and UVR in keratinocytes and melanocytes. Normal melanocytes are markedly more resistant to UVR-induced cytotoxicity than normal keratinocytes, but both cell types are equally sensitive to arsenite. Melanocytes were more resistant to arsenite and UVR stimulation of superoxide production than keratinocytes, but the concentration of arsenite necessary to inhibit the activity of the DNA repair protein poly(ADP-ribose)polymerase and enhance retention of UVR-induced DNA damage was essentially equivalent in both cell types. These findings suggest that although melanocytes are less sensitive than keratinocytes to initial UVR-mediated DNA damage, both of these important target cells in the skin share a mechanism related to arsenic inhibition of DNA repair. These findings suggest that concurrent chronic arsenic exposure could promote retention of unrepaired DNA damage in melanocytes and act as a co-carcinogen in melanoma.
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Cooper KL, King BS, Sandoval MM, Liu KJ, Hudson LG. Reduction of arsenite-enhanced ultraviolet radiation-induced DNA damage by supplemental zinc. Toxicol Appl Pharmacol 2013; 269:81-8. [PMID: 23523584 DOI: 10.1016/j.taap.2013.03.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 03/01/2013] [Accepted: 03/07/2013] [Indexed: 01/21/2023]
Abstract
Arsenic is a recognized human carcinogen and there is evidence that arsenic augments the carcinogenicity of DNA damaging agents such as ultraviolet radiation (UVR) thereby acting as a co-carcinogen. Inhibition of DNA repair is one proposed mechanism to account for the co-carcinogenic actions of arsenic. We and others find that arsenite interferes with the function of certain zinc finger DNA repair proteins. Furthermore, we reported that zinc reverses the effects of arsenite in cultured cells and a DNA repair target protein, poly (ADP-ribose) polymerase-1. In order to determine whether zinc ameliorates the effects of arsenite on UVR-induced DNA damage in human keratinocytes and in an in vivo model, normal human epidermal keratinocytes and SKH-1 hairless mice were exposed to arsenite, zinc or both before solar-simulated (ss) UVR exposure. Poly (ADP-ribose) polymerase activity, DNA damage and mutation frequencies at the Hprt locus were measured in each treatment group in normal human keratinocytes. DNA damage was assessed in vivo by immunohistochemical staining of skin sections isolated from SKH-1 hairless mice. Cell-based findings demonstrate that ssUVR-induced DNA damage and mutagenesis are enhanced by arsenite, and supplemental zinc partially reverses the arsenite effect. In vivo studies confirm that zinc supplementation decreases arsenite-enhanced DNA damage in response to ssUVR exposure. From these data we can conclude that zinc offsets the impact of arsenic on ssUVR-stimulated DNA damage in cells and in vivo suggesting that zinc supplementation may provide a strategy to improve DNA repair capacity in arsenic exposed human populations.
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Affiliation(s)
- Karen L Cooper
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, NM 87131, USA
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Qin XJ, Liu W, Li YN, Sun X, Hai CX, Hudson LG, Liu KJ. Poly(ADP-ribose) polymerase-1 inhibition by arsenite promotes the survival of cells with unrepaired DNA lesions induced by UV exposure. Toxicol Sci 2012; 127:120-9. [PMID: 22387748 DOI: 10.1093/toxsci/kfs099] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human arsenic exposure is associated with increased risk of skin cancer, and arsenite greatly enhances ultraviolet (UV)-induced skin tumors in a mouse model of carcinogenesis. Inhibition of DNA repair is one proposed mechanism for the observed cocarcinogenicity. We have previously demonstrated that low concentrations of arsenite inhibit poly(ADP-ribose) polymerase (PARP)-1, thus interfering with DNA repair process triggered by UV radiation. Because overactivation of PARP-1 often leads to apoptotic cell death, and unrepaired DNA lesions promote genomic instability and carcinogenesis, we hypothesized that inhibition of PARP-1 by arsenic may promote the survival of potentially "initiated carcinogenic cells," i.e., cells with unrepaired DNA lesions. In the present study, we tested this hypothesis on UV-challenged HaCat cells. Cells were pretreated with 2μM arsenite for 24 h before UV exposure. Outcome parameters included apoptotic death rate, PARP-1 activation, apoptotic molecules, and retention of DNA lesions. UV exposure induced PARP-1 activation and associated poly(ADP-ribose) production, apoptosis-inducing factor release, cytochrome C release, and caspases activation, which led to apoptotic death in HaCat cells. Pretreatment with 2μM arsenite significantly inhibited UV-induced cell death as well as the associated molecular events. Notably, knockdown of PARP-1 with small interfering RNA completely abolished the antagonism of arsenite. Furthermore, arsenite pretreatment led to long-term retention of UV-induced cyclobutane pyrimidine dimers. Together, these results suggest that low concentration of arsenite reduces UV-induced apoptosis via inhibiting PARP-1, thus promoting the survival of cells with unrepaired DNA lesions, which may be an important mechanism underlying arsenic cocarcinogenic action.
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Affiliation(s)
- Xu-Jun Qin
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131-0001, USA
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22
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Zhang Z, Wang X, Cheng S, Sun L, Son YO, Yao H, Li W, Budhraja A, Li L, Shelton BJ, Tucker T, Arnold SM, Shi X. Reactive oxygen species mediate arsenic induced cell transformation and tumorigenesis through Wnt/β-catenin pathway in human colorectal adenocarcinoma DLD1 cells. Toxicol Appl Pharmacol 2011; 256:114-21. [PMID: 21854796 DOI: 10.1016/j.taap.2011.07.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 07/27/2011] [Accepted: 07/28/2011] [Indexed: 10/17/2022]
Abstract
Long term exposure to arsenic can increase incidence of human cancers, such as skin, lung, and colon rectum. The mechanism of arsenic induced carcinogenesis is still unclear. It is generally believed that reactive oxygen species (ROS) may play an important role in this process. In the present study, we investigate the possible linkage between ROS, β-catenin and arsenic induced transformation and tumorigenesis in human colorectal adenocarcinoma cell line, DLD1 cells. Our results show that arsenic was able to activate p47(phox) and p67(phox), two key proteins for activation of NADPH oxidase. Arsenic was also able to generate ROS in DLD1 cells. Arsenic increased β-catenin expression level and its promoter activity. ROS played a major role in arsenic-induced β-catenin activation. Treatment of DLD1 cells by arsenic enhanced both transformation and tumorigenesis of these cells. The tumor volumes of arsenic treated group were much larger than those without arsenic treatment. Addition of either superoxide dismutase (SOD) or catalase reduced arsenic induced cell transformation and tumor formation. The results indicate that ROS are involved in arsenic induced cell transformation and tumor formation possible through Wnt/β-catenin pathway in human colorectal adenocarcinoma cell line DLD1 cells.
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Affiliation(s)
- Zhuo Zhang
- Department of Preventive Medicine and Environmental Health, University of Kentucky, 121 Washington Avenue, Lexington, KY 40536, USA
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Zhou X, Sun X, Cooper KL, Wang F, Liu KJ, Hudson LG. Arsenite interacts selectively with zinc finger proteins containing C3H1 or C4 motifs. J Biol Chem 2011; 286:22855-63. [PMID: 21550982 DOI: 10.1074/jbc.m111.232926] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Arsenic inhibits DNA repair and enhances the genotoxicity of DNA-damaging agents such as benzo[a]pyrene and ultraviolet radiation. Arsenic interaction with DNA repair proteins containing functional zinc finger motifs is one proposed mechanism to account for these observations. Here, we report that arsenite binds to both CCHC DNA-binding zinc fingers of the DNA repair protein PARP-1 (poly(ADP-ribose) polymerase-1). Furthermore, trivalent arsenite coordinated with all three cysteine residues as demonstrated by MS/MS. MALDI-TOF-MS analysis of peptides harboring site-directed substitutions of cysteine with histidine residues within the PARP-1 zinc finger revealed that arsenite bound to peptides containing three or four cysteine residues, but not to peptides with two cysteines, demonstrating arsenite binding selectivity. This finding was not unique to PARP-1; arsenite did not bind to a peptide representing the CCHH zinc finger of the DNA repair protein aprataxin, but did bind to an aprataxin peptide mutated to a CCHC zinc finger. To investigate the impact of arsenite on PARP-1 zinc finger function, we measured the zinc content and DNA-binding capacity of PARP-1 immunoprecipitated from arsenite-exposed cells. PARP-1 zinc content and DNA binding were decreased by 76 and 80%, respectively, compared with protein isolated from untreated cells. We observed comparable decreases in zinc content for XPA (xeroderma pigmentosum group A) protein (CCCC zinc finger), but not SP-1 (specificity protein-1) or aprataxin (CCHH zinc finger). These findings demonstrate that PARP-1 is a direct molecular target of arsenite and that arsenite interacts selectively with zinc finger motifs containing three or more cysteine residues.
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Affiliation(s)
- Xixi Zhou
- Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico, Albuquerque, New Mexico 87131-0001, USA
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Tang CH, Wei W, Liu L. Regulation of DNA repair by S-nitrosylation. Biochim Biophys Acta Gen Subj 2011; 1820:730-5. [PMID: 21571039 DOI: 10.1016/j.bbagen.2011.04.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 04/27/2011] [Accepted: 04/28/2011] [Indexed: 02/02/2023]
Abstract
BACKGROUND Expression of the inducible nitric oxide synthase (iNOS) is commonly induced in inflammation, an important risk factor of cancer. Nitric oxide (NO) and related reactive nitrogen species can directly cause DNA damage to increase DNA mutation. They can also indirectly affect DNA mutation by modulation of DNA repair proteins, in particular through protein S-nitrosylation, a key regulatory mechanism of NO. SCOPE OF REVIEW Here we review protein targets, molecular mechanisms, and potential roles of NO in the regulation of DNA repair, with a focus on S-nitrosylation of DNA repair proteins by endogenous NO synthase activity. MAJOR CONCLUSIONS Recent studies have identified a number of key DNA repair proteins as targets of S-nitrosylation, including O(6)-alkylguanine-DNA-alkyltransferase (AGT), 8-oxoguanine glycosylase, apurinic-apyrimidinic endonuclease 1, and DNA-dependent protein kinase catalytic subunit. S-nitrosylation has been shown to modulate the activity, stability, and cellular localization of DNA repair proteins. The level of protein S-nitrosylation depends both on NO synthesis by NO synthases and on denitrosylation by a major denitrosylase, S-nitrosoglutathione reductase (GSNOR). Dysregulated S-nitrosylation of AGT due to GSNOR deficiency inactivates AGT-dependent DNA repair and appears to contribute critically to hepatocarcinogenesis. GENERAL SIGNIFICANCE Studies on the S-nitrosylation of DNA repair proteins have started to reveal molecular mechanisms for the contribution of inflammation to mutagenesis and carcinogenesis. The modulation of protein S-nitrosylation to affect the activity of DNA repair proteins may provide a therapeutic strategy to prevent DNA damage and mutation frequently associated with chronic inflammation and to sensitize cancer cells to DNA-damaging drugs. This article is part of a Special Issue entitled Regulation of Cellular Processes by S-nitrosylation.
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Affiliation(s)
- Chi-Hui Tang
- The Department of Microbiology and Immunology, University of California, San Francisco, CA, United States
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Piao F, Li S, Li Q, Ye J, Liu S. Abnormal expression of 8-nitroguanine in the brain of mice exposed to arsenic subchronically. INDUSTRIAL HEALTH 2010; 49:151-157. [PMID: 21173536 DOI: 10.2486/indhealth.ms1058] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
To provide molecular toxicological evidences for exploring the mechanism of arsenic-induced neurotoxicity the accumulation of arsenic (As), the formation of 8-nitroguanine (8-NO(2)-G) were examined in brain tissue of mice exposed to arsenic. And the gene expressions of inducible NOS (iNOS), superoxide dismutase 1 (SOD1) and peroxiredoxin 2 (Prdx2) were also analyzed by GeneChip. In the result, the concentration of As in the brain tissue of mice was 4.00, 13.70, 21.48 and 29.88 ng/g in the controls and experimental groups exposed to 1, 2 and 4 mg/l As(2)O(3), respectively and increased in dose-response manner. Nervous cells in the brain of mice exposed to As showed disappearances of axons, vacuolar degeneration in cytoplasm and karyolysis, whereas no such pathological changes were observed in the control group. Weak immunoreactivity against 8-NO(2)-G was observed in the brain tissue of mice given 1 or 2 ppm arsenic trioxide. More intensive immunoreactivity was found in cells at 4 ppm and it was mainly distributed in cytoplasm. The expressions of SOD1 and Prdx2 were down-regulated in the brain of mice exposed to As, but iNOS expression was not disturbed by As exposure. No the 8-NO(2)-G immunoreactivity or abnormal expressions of these genes in brain tissue were observed in controls. These results indicate that As induces high expression of 8-NO(2)-G in brain tissues of mice and that RNA in the cells may be modified by overproduced reactive nitrogen species.
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Affiliation(s)
- Fengyuan Piao
- Department of Occupational and Environmental Health, Dalian Medical University, No 9 Western Section of Lvshun South Road, Dalian, Liaoning 116044, P.R. China.
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Li D, Li DW, Fossey JS, Long YT. Portable Surface-Enhanced Raman Scattering Sensor for Rapid Detection of Aniline and Phenol Derivatives by On-Site Electrostatic Preconcentration. Anal Chem 2010; 82:9299-305. [DOI: 10.1021/ac101812x] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dan Li
- Key Laboratory for Advanced Materials and Department of Chemistry, East China University of Science and Technology, Shanghai 200237, People’s Republic of China, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Da-Wei Li
- Key Laboratory for Advanced Materials and Department of Chemistry, East China University of Science and Technology, Shanghai 200237, People’s Republic of China, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - John S. Fossey
- Key Laboratory for Advanced Materials and Department of Chemistry, East China University of Science and Technology, Shanghai 200237, People’s Republic of China, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Yi-Tao Long
- Key Laboratory for Advanced Materials and Department of Chemistry, East China University of Science and Technology, Shanghai 200237, People’s Republic of China, and School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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Ma N, Sasoh M, Kawanishi S, Sugiura H, Piao F. Protection effect of taurine on nitrosative stress in the mice brain with chronic exposure to arsenic. J Biomed Sci 2010; 17 Suppl 1:S7. [PMID: 20804627 PMCID: PMC2994365 DOI: 10.1186/1423-0127-17-s1-s7] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Arsenic exposure induces overproduction of reactive nitrogen species (RNS) in brain tissue and results in nucleic acid damage to the nerve cells. The 8-nitroguanine is one of the major products formed by the reaction of guanine, and ONOO-, and has been used as a popular biomarker of nucleic acid damage due to RNS attacking. In the present study, we examined whether the administration of taurine can protect against nucleic acid damage of brain neurons by arsenic-induced RNS. MATERIALS AND METHODS Sixty mice (30 male and 30 female) weighing 19.5 +/- 1.5 g were divided into 3 groups: (1) control group, (2) experimental group that received arsenic (As2O3), and (3) antagonistic group that received taurine with arsenic. Arsenic was administered for 60 days. 8-Nitroguanine expressions in brain neurons of mice were examined by the immunohistochemical method. Histopathological changes in brain tissues of mice were observed under light microscope and the immunohistochemistry method was used to investigate 8-nitroguanine expressions in cerebrum and cerebellum of mice. RESULTS In the control group, no abnormal histopathological changes were observed in brain tissue of the mice. In brain tissue of the mice exposed to arsenic, histopathological results showed swells, evident vacuolar degeneration in cytoplasm, karyorrhexis and karyolysis. Relatively light pathological changes were observed in brain of the mice co-administered arsenic and taurine. Little or no expression of 8-nitroguanine in brain tissue was observed in controls. However, intensive expression of 8-nitroguanine was found in brain tissue of mice exposed to arsenic and it was mainly distributed in nucleus neighbouring the nuclear membrane, but a little in cytoplasm. A weak expression of 8-nitroguanine was observed in brain cells of mice co-administered arsenic and taurine. CONCLUSIONS The brain neurons may be the major target cells of arsenic neurotoxicity. Co-administration of arsenic and taurine can alleviate DNA damage of brain neurons caused by arsenic through the RNS signal pathway.
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Affiliation(s)
- Ning Ma
- Faculty of Health Science and Institute of Traditional Chinese Medicine, Suzuka University of Medical Science, Suzuka, Mie 510-0293, Japan.
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Ding W, Liu W, Cooper KL, Qin XJ, de Souza Bergo PL, Hudson LG, Liu KJ. Inhibition of poly(ADP-ribose) polymerase-1 by arsenite interferes with repair of oxidative DNA damage. J Biol Chem 2008; 284:6809-17. [PMID: 19056730 DOI: 10.1074/jbc.m805566200] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Arsenic enhances skin tumor formation when combined with other carcinogens, including UV radiation (UVR). In this study we report that low micromolar concentrations of arsenite synergistically increases UVR-induced oxidative DNA damage in human keratinocytes as detected by 8-hydroxyl-2'-deoxyguanine (8-OHdG) formation. Poly(ADP-ribose) polymerase-1 (PARP-1) is involved in base excision repair, a process that repairs 8-OHdG lesions. Arsenite suppresses UVR-induced PARP-1 activation in a concentration-dependent manner. Inhibition of PARP-1 activity by 3-aminobenzamide or small interfering RNA silencing of PARP-1 expression significantly increases UVR-induced 8-OHdG formation, suggesting that inhibition of PARP-1 activity by arsenite contributes to oxidative DNA damage. PARP-1 is a zinc finger protein, and mass spectrometry analysis reveals that arsenite can occupy a synthetic apopeptide representing the first zinc finger of PARP-1 (PARPzf). When the PARPzf peptide is preincubated with Zn(II) followed by incubation with increasing concentrations of arsenite, the ZnPARPzf signal is decreased while the AsPARPzf signal intensity is increased as a function of arsenite dose, suggesting a competition between zinc and arsenite for the same binding site. Addition of Zn(II) abolished arsenite enhancement of UVR-stimulated 8-OHdG generation and restored PARP-1 activity. Our findings demonstrate that arsenite inhibits oxidative DNA damage repair and suggest that interaction of arsenite with the PARP-1 zinc finger domain contributes to the inhibition of PARP-1 activity by arsenite. Arsenite inhibition of poly(ADP-ribosyl)ation is one likely mechanism for the reported co-carcinogenic activities of arsenic in UVR-induced skin carcinogenesis.
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Affiliation(s)
- Wei Ding
- Department of Pharmaceutical Sciences, University of New Mexico, Albuquerque, New Mexico 87131-0704, USA
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