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Nishimura A, Zhou L, Kato Y, Mi X, Ito T, Ibuki Y, Kanda Y, Nishida M. Supersulfide prevents cigarette smoke extract-induced mitochondria hyperfission and cardiomyocyte early senescence by inhibiting Drp1-filamin complex formation. J Pharmacol Sci 2024; 154:127-135. [PMID: 38246726 DOI: 10.1016/j.jphs.2023.12.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 12/14/2023] [Accepted: 12/20/2023] [Indexed: 01/23/2024] Open
Abstract
Smoking is one of the most serious risk factors for cardiovascular diseases. Although cigarette mainstream and sidestream smoke are significant contributors to increased cardiovascular mortality and morbidity, the underlying mechanism is still unclear. Here, we report that exposure of rat neonatal cardiomyocytes to cigarette smoke extract (CSE) induces mitochondrial hyperfission-mediated myocardial senescence. CSE leads to mitochondrial fission and reactive oxygen species (ROS) production through the complex formation between mitochondrial fission factor Drp1 and actin-binding protein, filamin A. Pharmacological perturbation of interaction between Drp1 and filamin A by cilnidipine and gene knockdown of Drp1 or filamin A inhibited CSE-induced mitochondrial hyperfission and ROS production as well as myocardial senescence. We previously reported that Drp1 activity is controlled by supersulfide-induced Cys644 polysulfidation. The redox-sensitive Cys644 was critical for CSE-mediated interaction with filamin A. The administration of supersulfide donor, Na2S3 also improved mitochondrial hyperfission-mediated myocardial senescence induced by CSE. Our results suggest the important role of Drp1-filamin A complex formation on cigarette smoke-mediated cardiac risk and the contribution of supersulfide to mitochondrial fission-associated myocardial senescence.
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Affiliation(s)
- Akiyuki Nishimura
- National Institute for Physiological Sciences, National Institutes of Natural Sciences (NINS), Okazaki, 444-8787, Japan; Exploratory Research Center on Life and Living Systems, NINS, Okazaki, 444-8787, Japan; SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8787, Japan.
| | - Liuchenzi Zhou
- National Institute for Physiological Sciences, National Institutes of Natural Sciences (NINS), Okazaki, 444-8787, Japan; Exploratory Research Center on Life and Living Systems, NINS, Okazaki, 444-8787, Japan; SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8787, Japan
| | - Yuri Kato
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Xinya Mi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan
| | - Tomoya Ito
- National Institute for Physiological Sciences, National Institutes of Natural Sciences (NINS), Okazaki, 444-8787, Japan; Exploratory Research Center on Life and Living Systems, NINS, Okazaki, 444-8787, Japan; SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8787, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, 422-8526, Japan
| | - Yasunari Kanda
- Division of Pharmacology, National Institute of Health Sciences, Kanagawa, 210-9501, Japan
| | - Motohiro Nishida
- National Institute for Physiological Sciences, National Institutes of Natural Sciences (NINS), Okazaki, 444-8787, Japan; Exploratory Research Center on Life and Living Systems, NINS, Okazaki, 444-8787, Japan; SOKENDAI (The Graduate University for Advanced Studies), Okazaki, 444-8787, Japan; Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, 812-8582, Japan.
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2
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Hirakawa K, Kishimoto N, Nishimura Y, Ibuki Y, Fuki M, Okazaki S. Protein Photodamaging Activity and Photocytotoxic Effect of an Axial-Connecting Phosphorus(V)porphyrin Trimer. Chem Res Toxicol 2023. [PMID: 37683091 DOI: 10.1021/acs.chemrestox.3c00182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/10/2023]
Abstract
An axial-connecting trimer of the porphyrin phosphorus(V) complex was synthesized to evaluate the relaxation process of the photoexcited state and the photosensitizer activity. The photoexcitation energy was localized on the central unit of the phosphorus(V)porphyrin trimer. The photoexcited state of the central unit was relaxed through a process similar to that of the monomer phosphorus(V)porphyrin. The excited state of this axially connected type of phosphorus(V)porphyrin trimer was not deactivated through intramolecular electron transfer. The singlet oxygen generation quantum yield of the trimer was almost the same as that of the monomer. The phosphorus(V)porphyrin, trimer, and monomer bound to human serum albumin and oxidized the tryptophan residue via singlet oxygen generation and electron transfer during visible light irradiation. The photocytotoxicity of these phosphorus(V)porphyrins on two cell lines was examined. The monomer induced photocytotoxicity; however, the trimer did not show cytotoxicity with or without photoirradiation. In summary, the photoexcited state of the trimer was almost the same as that of the monomer, and these phosphorus(V)porphyrins demonstrated a similar protein-photodamaging activity. The difference in association between the photosensitizer molecules and cells is the key factor of phototoxicity by these phosphorus(V)porphyrins.
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Affiliation(s)
- Kazutaka Hirakawa
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu 432-8561, Japan
- Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu 432-8561, Japan
- Cooperative Major in Medical Photonics, Shizuoka University, Johoku 3-5-1, Hamamatsu 432-8561, Japan
| | - Naoki Kishimoto
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu 432-8561, Japan
| | - Yoshinobu Nishimura
- Department of Chemistry, University of Tsukuba, Tennodai 1-1-1, Tsukuba ,Ibaraki 305-8571, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Masaaki Fuki
- Laser Molecular Photoscience Laboratory, Molecular Photoscience Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe 657-8501, Japan
| | - Shigetoshi Okazaki
- HAMAMATSU BioPhotonics Innovation Chair, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, Handayama 1-20-1, Higashi-ku, Hamamatsu 431-3192, Japan
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Komaki Y, Ono S, Okuya T, Ibuki Y. Glucose starvation impairs NER and γ-H2AX after UVB irradiation. Toxicol In Vitro 2023; 86:105503. [DOI: 10.1016/j.tiv.2022.105503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 09/12/2022] [Accepted: 10/17/2022] [Indexed: 11/07/2022]
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4
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Kato Y, Nishiyama K, Man Lee J, Ibuki Y, Imai Y, Noda T, Kamiya N, Kusakabe T, Kanda Y, Nishida M. TRPC3-Nox2 Protein Complex Formation Increases the Risk of SARS-CoV-2 Spike Protein-Induced Cardiomyocyte Dysfunction through ACE2 Upregulation. Int J Mol Sci 2022; 24:ijms24010102. [PMID: 36613540 PMCID: PMC9820218 DOI: 10.3390/ijms24010102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 12/24/2022] Open
Abstract
Myocardial damage caused by the newly emerged coronavirus (SARS-CoV-2) infection is one of the key determinants of COVID-19 severity and mortality. SARS-CoV-2 entry to host cells is initiated by binding with its receptor, angiotensin-converting enzyme (ACE) 2, and the ACE2 abundance is thought to reflect the susceptibility to infection. Here, we report that ibudilast, which we previously identified as a potent inhibitor of protein complex between transient receptor potential canonical (TRPC) 3 and NADPH oxidase (Nox) 2, attenuates the SARS-CoV-2 spike glycoprotein pseudovirus-evoked contractile and metabolic dysfunctions of neonatal rat cardiomyocytes (NRCMs). Epidemiologically reported risk factors of severe COVID-19, including cigarette sidestream smoke (CSS) and anti-cancer drug treatment, commonly upregulate ACE2 expression level, and these were suppressed by inhibiting TRPC3-Nox2 complex formation. Exposure of NRCMs to SARS-CoV-2 pseudovirus, as well as CSS and doxorubicin (Dox), induces ATP release through pannexin-1 hemi-channels, and this ATP release potentiates pseudovirus entry to NRCMs and human iPS cell-derived cardiomyocytes (hiPS-CMs). As the pseudovirus entry followed by production of reactive oxygen species was attenuated by inhibiting TRPC3-Nox2 complex in hiPS-CMs, we suggest that TRPC3-Nox2 complex formation triggered by panexin1-mediated ATP release participates in exacerbation of myocardial damage by amplifying ACE2-dependent SARS-CoV-2 entry.
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Affiliation(s)
- Yuri Kato
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Kazuhiro Nishiyama
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Jae Man Lee
- Laboratory of Creative Science for Insect Industries, Faculty of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Yumiko Imai
- Laboratory of Regulation for Intractable Infectious Diseases, Center for Vaccine and Adjuvant Research (CVAR), National Institutes of Biomedical Innovation Health and Nutrition (NIBIOHN), Osaka 567-0085, Japan
| | - Takamasa Noda
- Department of Psychiatry, National Center of Neurology and Psychiatry, Tokyo 187-8551, Japan
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo 187-8551, Japan
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo 187-8553, Japan
- Department of Brain Bioregulatory Science, The Jikei University Graduate School of Medicine, Tokyo 105-8461, Japan
| | - Noriho Kamiya
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan
- Division of Biotechnology, Center for Future Chemistry, Kyushu University, Fukuoka 819-0395, Japan
| | - Takahiro Kusakabe
- Laboratory of Insect Genome Science, Faculty of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
| | - Yasunari Kanda
- Division of Pharmacology, National Institute of Health Sciences (NIHS), Kawasaki 210-9501, Japan
| | - Motohiro Nishida
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan
- National Institute for Physiological Sciences, Exploratory Research Center on Life and Living Systems, National Institutes of Natural Sciences, Okazaki 444-8787, Japan
- Correspondence: ; Tel./Fax: +81-92-642-6556
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5
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Tanaka M, Komaki Y, Toyooka T, Ibuki Y. Butyrate Enhances γ-H2AX Induced by Benzo[ a]pyrene. Chem Res Toxicol 2022; 35:2241-2251. [PMID: 36399157 DOI: 10.1021/acs.chemrestox.2c00238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Benzo[a]pyrene (BaP) is known to form DNA adduct following metabolic activation, which causes phosphorylation of histone H2AX (γ-H2AX). Recent studies have shown that histone deacetylase (HDAC) inhibitors enhanced BaP-induced CYP1A1 gene expression. In this study, we examined the relationship between the HDAC inhibitor-augmented metabolic activation and BaP-induced γ-H2AX. Sodium butyrate (SB), a typical HDAC inhibitor, enhanced BaP-induced γ-H2AX. The enhanced DNA damage was further confirmed by biased sinusoidal field gel electrophoresis, which detects DNA double-strand breaks. SB remarkably augmented BaP-induced CYP1A1 gene expression, and CYP1A1-overexpressing cells showed elevated generation of γ-H2AX. Furthermore, SB enhanced intracellular oxidation after treatment with BaP. These results suggested that SB-induced CYP1A1 upregulation facilitated BaP metabolism, which might result in excess DNA adducts or oxidative DNA damages, leading to augmentation of γ-H2AX.
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Affiliation(s)
- Miki Tanaka
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Tatsushi Toyooka
- National Institute of Occupational Safety and Health, 6-21-1 Nagao, Tama-ku, Kawasaki 214-8585, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
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6
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Komaki Y, Suganuma K, Ibuki Y. Protective role of electrophile-reactive glutathione for DNA damage repair inhibitory effect of dibromoacetonitrile. J Environ Sci (China) 2022; 117:305-314. [PMID: 35725084 DOI: 10.1016/j.jes.2022.05.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Dibromoacetonitrile (DBAN) is a disinfection byproduct (DBP) and linked with cancer in rodents, but the mechanism of its carcinogenicity has not been fully elucidated. We recently reported that DBAN induced inhibition of nucleotide excision repair (NER). In this study, we investigated if glutathione (GSH) is involved in the DBAN-induced inhibition of NER. Human keratinocytes HaCaT were pretreated with L-buthionine-(S,R)-sulfoximine (BSO) to deplete intracellular GSH. BSO treatment markedly potentiated the DBAN-induced NER inhibition as well as intracellular oxidation. The recruitment of NER proteins (transcription factor IIH, and xeroderma pigmentosum complementation group G) to DNA damage sites was inhibited by DBAN, which was further exacerbated by BSO treatment. Our results suggest that intracellular GSH protects cells from DBAN-induced genotoxicity including inhibition of DNA damage repair.
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Affiliation(s)
- Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan.
| | - Koki Suganuma
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka 422-8526, Japan
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7
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Walker N, Ibuki Y, McLinden P, Lama V. MNK/eIF4E Ser209 Inhibitor eFT-508 Prevents and Therapeutically Treats Fibrosis in a Murine Model of Restrictive Chronic Lung Allograft Rejection. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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8
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Komaki Y, Ibuki Y. Inhibition of nucleotide excision repair and damage response signaling by dibromoacetonitrile: A novel genotoxicity mechanism of a water disinfection byproduct. J Hazard Mater 2022; 423:127194. [PMID: 34844342 DOI: 10.1016/j.jhazmat.2021.127194] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/04/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Abstract
Dibromoacetonitrile (DBAN) is a carcinogenic disinfection byproduct (DBP) but how it precipitates cancer is unknown. Nucleotide excision repair (NER) is a versatile repair mechanism for removing bulky DNA lesions to maintain genome stability, and impairment of this process is associated with cancer development. In this study, we found that DBAN inhibited NER and investigated its mechanism with other DNA damage responses. Human keratinocytes HaCaT were treated with DBAN followed by ultraviolet (UV) as a model inducer of DNA damage, pyrimidine dimers, which require NER for the removal. DBAN pretreatment exacerbated UV-cytotoxicity, and inhibited the repair of pyrimidine dimers. DBAN treatment delayed the recruitment of NER proteins, transcription factor IIH (TFIIH) and xeroderma pigmentosum complementation group G (XPG), to DNA damaged sites, and subsequent gap filling process. Moreover, DBAN suppressed the UV-induced double strand breaks (DSBs) formation, as well as phosphorylated histone H2AX (γ-H2AX), a widely used DNA damage marker. Altogether, DBAN could negatively impact the NER process and phosphorylation pathway responding to DNA damage. This study was the first to identify the inhibition of NER and damage response signaling as a genotoxicity mechanism of a class of DBPs and it may serve as a foundation for DBP carcinogenesis.
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Affiliation(s)
- Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
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9
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Shikata M, Toyooka T, Komaki Y, Ibuki Y. 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone-Induced Histone Acetylation via α7nAChR-Mediated PI3K/Akt Activation and Its Impact on γ-H2AX Generation. Chem Res Toxicol 2021; 34:2512-2521. [PMID: 34784199 DOI: 10.1021/acs.chemrestox.1c00287] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A typical tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is known as a strong carcinogen. We previously reported that metabolized NNK induced histone H2AX phosphorylation (γ-H2AX), a DNA damage-induced histone modification. In this study, we found that NNK globally acetylated histone H3, which affected γ-H2AX generation. Human lung adenocarcinoma A549 was treated with several doses of NNK. NNK induced dose-dependent global histone H3 acetylation (Ac-H3), at 2 to 12 h after the treatment, independent of the cell cycle. The Ac-H3 pattern was not affected by CYP2A13 overexpression unlike γ-H2AX, indicating no requirement of NNK metabolism to induce Ac-H3. Immunofluorescence staining of Ac-H3 was uniform throughout the nucleus, whereas γ-H2AX was formed as foci and did not coincide with Ac-H3. Nicotinic receptor antagonist methyllycaconitine inhibited Ac-H3 and also γ-H2AX. Phosphoinositide-3-kinase (PI3K)/Akt inhibitors, LY294002, wortmannin, and GSK690693, also suppressed both Ac-H3 and γ-H2AX, whereas KU-55933, an inhibitor of ataxia telangiectasia mutated (ATM) upstream of γ-H2AX, inhibited γ-H2AX but not Ac-H3. These results suggested that binding of NNK to the nicotinic acetylcholine receptor (α7nAChR) activated the PI3K/Akt pathway, resulting in Ac-H3. The activated pathway leading to Ac-H3 enhanced γ-H2AX, suggesting that NNK-induced DNA damage is impacted by the α7nAChR-mediated signal transduction pathway.
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Affiliation(s)
- Mariko Shikata
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Tatsushi Toyooka
- National Institute of Occupational Safety and Health, 6-21-1 Nagao, Tama-ku, Kawasaki 214-8585, Japan
| | - Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
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10
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Fukuda T, Komaki Y, Mori Y, Ibuki Y. Low extracellular pH inhibits nucleotide excision repair. Mutat Res 2021; 867:503374. [PMID: 34266626 DOI: 10.1016/j.mrgentox.2021.503374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 11/15/2022]
Abstract
Nucleotide excision repair (NER) is the main pathway to repair bulky DNA damages including pyrimidine dimers, and the genetic dysregulation of NER associated proteins is well known to cause diseases such as cancer and neurological disorder. Other than the genetic defects, 'external factors' such as oxidative stress and environmental chemicals also affect NER. In this study, we examined the impact of extracellular pH on NER. We prepared the culture media, whose pH values are 8.4 (normal condition), 7.6, 6.6 and 6.2 under atmospheric CO2 conditions. Human keratinocytes, HaCaT, slightly died after 48 h incubation in DMEM at pH 8.4, 7.6 and 6.6, while in pH 6.2 condition, marked cell death was induced. UV-induced pyrimidine dimers, pyrimidine (6-4) pyrimidone photoproducts (6-4PPs) and cyclobutane pyrimidine dimers (CPDs), were effectively repaired at 60 min and 24 h, respectively, which were remarkably inhibited at pH 6.6 and 6.2. The associated repair molecule, TFIIH, was accumulated to the damaged sites 5 min after UVC irradiation in all pH conditions, but the release was delayed as the pH got lower. Furthermore, accumulation of XPG at 5 min was delayed at pH 6.2 and 6.6, and the release at 60 min was completely suppressed. At the low pH, the DNA synthesis at the gaps created by incision of oligonucleotides containing pyrimidine dimers was significantly delayed. In this study, we found that the low extracellular pH inhibited NER pathway. This might partially contribute to carcinogenesis in inflamed tissues, which exhibit acidic pH.
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Affiliation(s)
- Tetsuya Fukuda
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
| | - Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
| | - Yuta Mori
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan.
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Ibuki Y, Komaki Y, Yang G, Toyooka T. Long-wavelength UVA enhances UVB-induced cell death in cultured keratinocytes: DSB formation and suppressed survival pathway. Photochem Photobiol Sci 2021; 20:639-652. [PMID: 33978941 DOI: 10.1007/s43630-021-00050-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 04/28/2021] [Indexed: 11/30/2022]
Abstract
Solar UV radiation consists of both UVA and UVB. The wavelength-specific molecular responses to UV radiation have been studied, but the interaction between UVA and UVB has not been well understood. In this study, we found that long-wavelength UVA, UVA1, augmented UVB-induced cell death, and examined the underlying mechanisms. Human keratinocytes HaCaT were exposed to UVA1, followed by UVB irradiation. Irradiation by UVA1 alone showed no effect on cell survival, whereas the UVA1 pre-irradiation remarkably enhanced UVB-induced cell death. UVA1 delayed the repair of pyrimidine dimers formed by UVB and the accumulation of nucleotide excision repair (NER) proteins to damaged sites. Gap synthesis during NER was also decreased, suggesting that UVA1 delayed NER, and unrepaired pyrimidine dimers and single-strand breaks generated in the process of NER were left behind. Accumulation of this unrepaired DNA damage might have led to the formation of DNA double-strand breaks (DSBs), as was detected using gel electrophoresis analysis and phosphorylated histone H2AX assay. Combined exposure enhanced the ATM-Chk2 signaling pathway, but not the ATR-Chk1 pathway, confirming the enhanced formation of DSBs. Moreover, UVA1 suppressed the UVB-induced phosphorylation of Akt, a survival signal pathway. These results indicated that UVA1 influenced the repair of UVB-induced DNA damage, which resulted in the formation of DSBs and enhanced cell death, suggesting the risk of simultaneous exposure to high doses of UVA1 and UVB.
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Affiliation(s)
- Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan.
| | - Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan
| | - Guang Yang
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan
| | - Tatsushi Toyooka
- National Institute of Occupational Safety and Health, Kawasaki, Japan
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12
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Yamashita R, Komaki Y, Yang G, Ibuki Y. Cell line-dependent difference in glutathione levels affects the cigarette sidestream smoke-induced inhibition of nucleotide excision repair. Mutat Res Genet Toxicol Environ Mutagen 2020; 858-860:503273. [PMID: 33198939 DOI: 10.1016/j.mrgentox.2020.503273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 09/15/2020] [Accepted: 09/21/2020] [Indexed: 10/23/2022]
Abstract
We recently reported that cigarette sidestream smoke (CSS) induced inhibition of nucleotide excision repair (NER) and the cause was NER molecule degradation by aldehydes contained in CSS [Carcinogenesis39, 56-65, 2018; Mutat. Res.834, 42-50, 2018]. In this study, we examined the relationship between intracellular glutathione (GSH) levels and CSS-induced NER inhibition. CSS treatment decreased the intracellular GSH level in human keratinocytes HaCaT, in which the repair of pyrimidine (6-4) pyrimidone photoproducts (6-4PPs) after UVB irradiation was suppressed. We used l-buthionine-(S,R)-sulfoximine (BSO) to artificially deplete intracellular GSH level. BSO treatment remarkably accelerated the CSS-induced NER inhibition. The NER inhibition by CSS was attributed to the delay of accumulation of NER molecules (TFIIH and XPG) to DNA damaged sites, which was further enhanced by BSO treatment. CSS degraded TFIIH, and BSO promoted it as expected. Formaldehyde (FA), a major constituent of CSS, showed similar intracellular GSH reduction and NER inhibition, and BSO promoted its inhibitory effect. Five cultured cell lines showed considerable variability in intrinsic GSH levels, and CSS-induced NER inhibitory effect was significantly correlated with the GSH levels. Chemicals like aldehydes are known to react not only with proteins but also with DNA, causing DNA lesions targeted by NER. Our results suggest that the tissues and cells with low intrinsic GSH levels are susceptible to treatment with CSS and electrophilic compounds like aldehydes through NER inhibition, thus leading to higher genotoxicity and carcinogenicity.
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Affiliation(s)
- Riko Yamashita
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan
| | - Yukako Komaki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan
| | - Guang Yang
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka, 422-8526, Japan.
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Hirakawa K, Suzuki A, Ouyang D, Okazaki S, Ibuki Y, Nakazaki J, Segawa H. Controlled Photodynamic Action of Axial Fluorinated DiethoxyP(V)tetrakis( p-methoxyphenyl)porphyrin through Self-Aggregation. Chem Res Toxicol 2019; 32:1638-1645. [PMID: 31273983 DOI: 10.1021/acs.chemrestox.9b00172] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
DiethoxyP(V)tetrakis(p-methoxyphenyl)porphyrin (EtP(V)TMPP) and its fluorinated derivative (FEtP(V)TMPP) were synthesized to examine their photodynamic action. These P(V)porphyrins were aggregated in an aqueous solution, resulting in the suppression of their photodynamic activity. In the presence of human serum albumin (HSA), a water-soluble protein, the aggregation states were resolved and formed a binding complex between P(V)porphyrin and HSA. These P(V)porphyrins photosensitized the oxidation of the tryptophan residue of HSA under the irradiation of long-wavelength visible light (>630 nm). This protein photodamage was explained by the electron transfer from tryptophan to the photoexcited state of P(V)porphyrins and singlet oxygen generation. The axial fluorination reduced the redox potential of the one-electron reduction of P(V)porphyrin and increased the electron transfer rate constant. However, this axial fluorination decreased the binding constant with HSA, and the quantum yield of photosensitized HSA damage through electron transfer was decreased. The photocytotoxicity of these P(V)porphyrins to HaCaT cells was also confirmed, and FEtP(V)TMPP demonstrated stronger phototoxicity than EtP(V)TMPP. In summary, a self-aggregation of porphyrin photosensitizers and resolving by targeting biomacromolecules may be used to target selective photodynamic action. The redox potential and an association with a targeting biomolecule are the important factors of the electron transfer-mediated mechanism, which is advantageous under hypoxic tumor conditions.
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Affiliation(s)
- Kazutaka Hirakawa
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology , Shizuoka University , Johoku 3-5-1 , Naka-ku, Hamamatsu 432-8561 , Japan.,Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology , Shizuoka University , Johoku 3-5-1 , Naka-ku, Hamamatsu 432-8561 , Japan
| | - Ayaka Suzuki
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology , Shizuoka University , Johoku 3-5-1 , Naka-ku, Hamamatsu 432-8561 , Japan
| | - Dongyan Ouyang
- Research Center of Integrative Molecular Systems (CIMoS), Institute for Molecular Sciences , National Institutes of Natural Sciences , 38 Nishigo-Naka , Myodaiji, Okazaki 444-8585 , Japan
| | - Shigetoshi Okazaki
- Department of Medical Spectroscopy Preeminent Medical Photonics Education & Research Center , Hamamatsu University School of Medicine , Handayama 1-20-1 , Higashi-ku, Hamamatsu 431-3192 , Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences , University of Shizuoka , Yada 52-1 , Suruga-ku, Shizuoka 422-8526 , Japan
| | - Jotaro Nakazaki
- Department of General Systems Studies, Graduate School of Arts and Sciences , The University of Tokyo , Komaba 3-8-1 , Meguro-ku, Tokyo 153-8902 , Japan
| | - Hiroshi Segawa
- Department of General Systems Studies, Graduate School of Arts and Sciences , The University of Tokyo , Komaba 3-8-1 , Meguro-ku, Tokyo 153-8902 , Japan
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14
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Nishiyama K, Numaga-Tomita T, Fujimoto Y, Tanaka T, Toyama C, Nishimura A, Yamashita T, Matsunaga N, Koyanagi S, Azuma YT, Ibuki Y, Uchida K, Ohdo S, Nishida M. Ibudilast attenuates doxorubicin-induced cytotoxicity by suppressing formation of TRPC3 channel and NADPH oxidase 2 protein complexes. Br J Pharmacol 2019; 176:3723-3738. [PMID: 31241172 DOI: 10.1111/bph.14777] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 05/30/2019] [Accepted: 06/14/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Doxorubicin is a highly effective anticancer agent but eventually induces cardiotoxicity associated with increased production of ROS. We previously reported that a pathological protein interaction between TRPC3 channels and NADPH oxidase 2 (Nox2) contributed to doxorubicin-induced cardiac atrophy in mice. Here we have investigated the effects of ibudilast, a drug already approved for clinical use and known to block doxorubicin-induced cytotoxicity, on the TRPC3-Nox2 complex. We specifically sought evidence that this drug attenuated doxorubicin-induced systemic tissue wasting in mice. EXPERIMENTAL APPROACH We used the RAW264.7 macrophage cell line to screen 1,271 clinically approved chemical compounds, evaluating functional interactions between TRPC3 channels and Nox2, by measuring Nox2 protein stability and ROS production, with and without exposure to doxorubicin. In male C57BL/6 mice, samples of cardiac and gastrocnemius muscle were taken and analysed with morphometric, immunohistochemical, RT-PCR and western blot methods. In the passive smoking model, cells were exposed to DMEM containing cigarette sidestream smoke. KEY RESULTS Ibudilast, an anti-asthmatic drug, attenuated ROS-mediated muscle toxicity induced by doxorubicin treatment or passive smoking, by inhibiting the functional interactions between TRPC3 channels and Nox2, without reducing TRPC3 channel activity. CONCLUSIONS AND IMPLICATIONS These results indicate a common mechanism underlying induction of systemic tissue wasting by doxorubicin. They also suggest that ibudilast could be repurposed to prevent muscle toxicity caused by anticancer drugs or passive smoking.
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Affiliation(s)
- Kazuhiro Nishiyama
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Takuro Numaga-Tomita
- National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS), Okazaki, Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS), NINS, Okazaki, Japan.,Department of Physiological Sciences, SOKENDAI (School of Life Science, The Graduate University for Advanced Studies), Okazaki, Japan
| | - Yasuyuki Fujimoto
- National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS), Okazaki, Japan.,Division of Veterinary Science, Osaka Prefecture University Graduate School of Life and Environmental Science, Osaka, Japan
| | - Tomohiro Tanaka
- National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS), Okazaki, Japan.,Center for Novel Science Initiatives (CNSI), National Institutes of Natural Sciences, Tokyo, Japan
| | - Chiemi Toyama
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Akiyuki Nishimura
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.,National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS), Okazaki, Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS), NINS, Okazaki, Japan
| | - Tomohiro Yamashita
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Naoya Matsunaga
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Satoru Koyanagi
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Yasu-Taka Azuma
- Division of Veterinary Science, Osaka Prefecture University Graduate School of Life and Environmental Science, Osaka, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
| | - Koji Uchida
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
| | - Shigehiro Ohdo
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan
| | - Motohiro Nishida
- Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.,National Institute for Physiological Sciences (NIPS), National Institutes of Natural Sciences (NINS), Okazaki, Japan.,Exploratory Research Center on Life and Living Systems (ExCELLS), NINS, Okazaki, Japan.,Department of Physiological Sciences, SOKENDAI (School of Life Science, The Graduate University for Advanced Studies), Okazaki, Japan
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15
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Hamai Y, Emi M, Ibuki Y, Okada M. Clinical significance of 18F-fluorodeoxyglucose-positron emission tomography-positive lymph nodes to outcomes of trimodal therapy for esophageal squamous cell carcinoma. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy282.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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16
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Toyooka T, Yanagiba Y, Ibuki Y, Wang RS. Cover Image. J Appl Toxicol 2018. [DOI: 10.1002/jat.3706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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17
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Toyooka T, Yanagiba Y, Ibuki Y, Wang RS. Trichloroethylene exposure results in the phosphorylation of histone H2AX in a human hepatic cell line through cytochrome P450 2E1-mediated oxidative stress. J Appl Toxicol 2018; 38:1224-1232. [PMID: 29722447 DOI: 10.1002/jat.3632] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 03/16/2018] [Accepted: 03/22/2018] [Indexed: 01/21/2023]
Abstract
Trichloroethylene (TCE), a chlorinated hydrocarbon, was recently reclassified as a human carcinogen by the International Agency for Research on Cancer. Genotoxic events are known to be crucial steps in the initiation of cancer. The genotoxic properties of TCE have been examined in many studies using a standard battery of genotoxicity tests both in vitro and in vivo. However, consistent results have not been obtained, and studies investigating the mechanism behind the genotoxicity of this compound are lacking. In the present study, we examined the genotoxicity of TCE by assessing phosphorylated histone H2AX (γ-H2AX), a new sensitive and reliable marker of DNA damage, in WRL-68 cells, cultured human hepatocytes and mouse livers. Our results showed that TCE exposure results in the generation of γ-H2AX, both in vitro and in vivo. By investigating the in vitro mechanism, we found that TCE increases the levels of intracellular reactive oxygen species (ROS) and that this increase in ROS levels is attenuated in the presence of disulfiram, a specific cytochrome P450 2E1 (CYP2E1) inhibitor. Furthermore, γ-H2AX induced by TCE was also attenuated by CYP2E1 inhibitors and the antioxidant N-acetylcysteine. These results suggested that ROS, produced via cytochrome P450 2E1-mediated metabolic processing, is a major causal factor for γ-H2AX generation upon exposure to TCE.
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Affiliation(s)
- Tatsushi Toyooka
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
| | - Yukie Yanagiba
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Japan
| | - Rui-Sheng Wang
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
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18
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Hirakawa K, Ouyang D, Ibuki Y, Hirohara S, Okazaki S, Kono E, Kanayama N, Nakazaki J, Segawa H. Photosensitized Protein-Damaging Activity, Cytotoxicity, and Antitumor Effects of P(V)porphyrins Using Long-Wavelength Visible Light through Electron Transfer. Chem Res Toxicol 2018; 31:371-379. [DOI: 10.1021/acs.chemrestox.8b00059] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Kazutaka Hirakawa
- Applied Chemistry and Biochemical Engineering Course, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology, Shizuoka University, Johoku 3-5-1, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
| | - Dongyan Ouyang
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Sciences, National Institutes of Natural Sciences, 38 Nishigo-Naka, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka, Shizuoka 422-8526, Japan
| | - Shiho Hirohara
- Department of Chemical and Biological Engineering, National Institute of Technology, Ube College, Tokiwadai, Ube, Yamaguchi 755-8555, Japan
| | - Shigetoshi Okazaki
- Department of Medical Spectroscopy, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, Handayama 1-20-1, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan
| | - Eiji Kono
- Department of Medical Spectroscopy, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, Handayama 1-20-1, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan
| | - Naohiro Kanayama
- Department of Medical Spectroscopy, Preeminent Medical Photonics Education & Research Center, Hamamatsu University School of Medicine, Handayama 1-20-1, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan
| | - Jotaro Nakazaki
- Department of General Systems Studies, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan
| | - Hiroshi Segawa
- Department of General Systems Studies, Graduate School of Arts and Sciences, The University of Tokyo, Komaba 3-8-1, Meguro-ku, Tokyo 153-8902, Japan
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19
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Yang G, Ibuki Y. α,β-Unsaturated Aldehyde-Induced Delays in Nucleotide Excision Repair and the Contribution of Reactive Oxygen Species. Chem Res Toxicol 2018; 31:145-155. [DOI: 10.1021/acs.chemrestox.7b00304] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Guang Yang
- Graduate Division of Nutritional
and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional
and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
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20
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Yang G, Ibuki Y. Cigarette sidestream smoke delays nucleotide excision repair: inhibited accumulation of repair proteins at DNA lesions. Carcinogenesis 2018; 39:56-65. [PMID: 29045565 DOI: 10.1093/carcin/bgx109] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 09/29/2017] [Indexed: 12/16/2023] Open
Abstract
Cigarette sidestream smoke (CSS) contains many carcinogens that induce DNA damage. DNA damage plays an important role in the initiation of cancer and several diseases, and repair is the major defense mechanism; however, the relationship between CSS and the repair of DNA damage remains unclear. We herein investigated whether CSS influences nucleotide excision repair (NER) in vivo and in vitro. HR-1 hairless mouse skin treated with CSS was exposed to UVB, as a result of which pyrimidine dimers (cyclobutane pyrimidine dimers (CPDs) and pyrimidine(6-4)pyrimidone photoproducts (6-4PPs)) were formed and repaired via the NER pathway. The immunohistochemical staining of CPDs revealed that their repair was delayed by the CSS treatment. This delay in NER and the underlying mechanisms were examined in the human skin cell lines, HaCaT and HSC-1. Dot-blot assays, enzyme-linked immunosorbent assay and local ultraviolet irradiation assays demonstrated that CSS delayed the repair of CPDs and 6-4PPs. The recruitment of the repair molecules, TFIIH, XPA and XPG to pyrimidine dimers was markedly inhibited by CSS. Semicarbazide, which reacts with aldehydes, recovered the CSS-induced inhibition of NER, and formaldehyde exerted similar inhibitory effects to those of CSS. These results suggest that aldehydes in CSS interfere with the recruitment of NER molecules to damaged sites, leading to a delay in the repair of pyrimidine dimers.
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Affiliation(s)
- Guang Yang
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada, Shizuoka, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Yada, Shizuoka, Japan
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21
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Nakamura K, Kitahara Y, Ibuki Y, Kogure K, Kigure K, Hirakawa T, Kanuma T. Continuing neoadjuvant chemotherapy until CA-125 reaches the nadir improves complete cytoreduction by interval debulking surgery in patients with advanced epithelial ovarian cancer. Gynecol Oncol 2017. [DOI: 10.1016/j.ygyno.2017.03.233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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22
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Zhao X, Toyooka T, Ibuki Y. Silver nanoparticle-induced phosphorylation of histone H3 at serine 10 is due to dynamic changes in actin filaments and the activation of Aurora kinases. Toxicol Lett 2017; 276:39-47. [PMID: 28499611 DOI: 10.1016/j.toxlet.2017.05.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 04/08/2017] [Accepted: 05/05/2017] [Indexed: 12/25/2022]
Abstract
The phosphorylation of histone H3 at serine 10 (p-H3S10) has been closely correlated with mitotic chromosome condensation. We previously reported that silver nanoparticles (AgNPs) significantly induced p-H3S10 independent of mitosis. In the present study, we examined the mechanisms underlying the induction of p-H3S10 by AgNPs. A treatment with AgNPs markedly induced p-H3S10 in a dose-dependent manner in three types of cell lines, and this was dependent on the cellular incorporation of AgNPs. The immunofluorescent staining of AgNP-induced p-H3S10 was thin and solid throughout the nucleus, and differed from that normally associated with mitosis. AgNPs induced the formation of globular actin in a dose-dependent manner. Latrunculin B (LatB) and phalloidin, inhibitors of actin polymerization and depolymerization, respectively, inhibited p-H3S10, suggesting that dynamic changes in actin filaments are related to AgNP-induced p-H3S10. Furthermore, p-H3S10 was mediated by Aurora kinase (AURK) pathways, which were suppressed by LatB and siRNA for cofilin 1, an actin-depolymerizing protein. AgNO3 (Ag ions) exerted similar effects to those of AgNPs. These results suggest that Ag ions released from AgNPs incorporated into inner cells changed the dynamics of actin filaments, and this was followed by the activation of AURKs, leading to the induction of p-H3S10.
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Affiliation(s)
- Xiaoxu Zhao
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
| | - Tatsushi Toyooka
- Industrial Toxicology and Health Effects Research Group, National Institute of Occupational Safety and Health, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan.
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23
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Kato T, Toyooka T, Ibuki Y, Masuda S, Watanabe M, Totsuka Y. Effect of physicochemical character differences on the genotoxic potency of kaolin. Genes Environ 2017; 39:12. [PMID: 28469735 PMCID: PMC5410691 DOI: 10.1186/s41021-017-0075-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/03/2017] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Kaolin is white clay mineral with the chemical composition Al2Si2O5(OH)4, and many varieties of kaolins having different crystal structures are utilized in industrial, cosmetic and medical fields. To evaluate the effect of physicochemical character differences on the genotoxicity of kaolin, two types of kaolin, kaolin-S with smooth, sphere-shaped crystals, and kaolin-P with clusters of thin pseudohexagonal plates, were used in the study. RESULTS ICR mice were intratracheally instilled with the kaolins (0.05 and 0.2 mg/mouse), and comet assay was performed on their lungs. Both kaolins showed DNA damage in the lungs of the mice, however the DNA damaging potency was much higher with kaolin-P than that with kaolin-S. In order to clarify the mechanisms for the different genotoxic potency, we examined the incorporation rate and ROS generation of these two types of kaolin in alveolar epithelial A549 and macrophage-like RAW264 cells, using flow cytometric (FCM) analysis. Kaolin-P showed a higher incorporation rate into the mammalian cells and ROS generation than that of kaolin-S. Especially, RAW264 cells aggressively incorporated kaolins, and generated ROS, whereas almost no ROS generation was observed in A549 cells. In addition, inflammatory cytokines were quantified, using the ELISA method, to understand further genotoxic potency differences of kaolins. Concentrations of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the media were increased by exposure to both kaolins, but in the case of kaolin-P, these inflammatory cytokines were significantly elevated. Based on these findings, differences of genotoxic potency may contribute to incorporation rates into immune cells. Furthermore, it is likely that immune cells and epithelial cells might closely interact with each other for the appearance of genotoxocity in vivo. In order to clarify the interaction between epithelial and immune cells, A549 and RAW264 were co-cultured and RAW264 cells only were exposed to kaolins, then subsequently A549 was applied to FCM analysis and comet assay. DNA damage observed in the A549 cells markedly increased in the presence of kaolin-exposed RAW264 cells compared to the single culture. CONCLUSION From these observations, it is suggested that mechanisms of kaolin genotoxicity against epithelial cells are through the activation of macrophage cells. Therefore, it is thought that interactions between epithelial and immune cells would be very important for evaluation of the genotoxicity of fine particulate matter. We also showed here that co-culture models of epithelial and immune cells could be used as suitable models for evaluation of lung genotoxicity of fine particulate matter, including nanomaterials, as in vivo mimicking systems.
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Affiliation(s)
- Tatsuya Kato
- Division of Carcinogenesis and Cancer Prevention, National Cancer Center Research Institute, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo, 104-0045 Japan
| | - Tatsushi Toyooka
- Graduate School of Food and Nutritional Sciences, University of Shizuoka, 52-1, Yada, Shizuoka 422-8526 Japan
- Present Address: National Institute of Occupational Safety and Health, Nagao 6-21-1, Tama-Ku, Kawasaki, 214-8585 Japan
| | - Yuko Ibuki
- Graduate School of Food and Nutritional Sciences, University of Shizuoka, 52-1, Yada, Shizuoka 422-8526 Japan
| | - Shuichi Masuda
- Graduate School of Food and Nutritional Sciences, University of Shizuoka, 52-1, Yada, Shizuoka 422-8526 Japan
| | - Masatoshi Watanabe
- Division of Materials Science and Engineering, Graduate School of Engineering, Yokohama National University, Hodogaya-ku, Yokohama, Japan
| | - Yukari Totsuka
- Division of Carcinogenesis and Cancer Prevention, National Cancer Center Research Institute, 1-1 Tsukiji 5-chome, Chuo-ku, Tokyo, 104-0045 Japan
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24
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Nelson BC, Wright CW, Ibuki Y, Moreno-Villanueva M, Karlsson HL, Hendriks G, Sims CM, Singh N, Doak SH. Emerging metrology for high-throughput nanomaterial genotoxicology. Mutagenesis 2016; 32:215-232. [PMID: 27565834 DOI: 10.1093/mutage/gew037] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The rapid development of the engineered nanomaterial (ENM) manufacturing industry has accelerated the incorporation of ENMs into a wide variety of consumer products across the globe. Unintentionally or not, some of these ENMs may be introduced into the environment or come into contact with humans or other organisms resulting in unexpected biological effects. It is thus prudent to have rapid and robust analytical metrology in place that can be used to critically assess and/or predict the cytotoxicity, as well as the potential genotoxicity of these ENMs. Many of the traditional genotoxicity test methods [e.g. unscheduled DNA synthesis assay, bacterial reverse mutation (Ames) test, etc.,] for determining the DNA damaging potential of chemical and biological compounds are not suitable for the evaluation of ENMs, due to a variety of methodological issues ranging from potential assay interferences to problems centered on low sample throughput. Recently, a number of sensitive, high-throughput genotoxicity assays/platforms (CometChip assay, flow cytometry/micronucleus assay, flow cytometry/γ-H2AX assay, automated 'Fluorimetric Detection of Alkaline DNA Unwinding' (FADU) assay, ToxTracker reporter assay) have been developed, based on substantial modifications and enhancements of traditional genotoxicity assays. These new assays have been used for the rapid measurement of DNA damage (strand breaks), chromosomal damage (micronuclei) and for detecting upregulated DNA damage signalling pathways resulting from ENM exposures. In this critical review, we describe and discuss the fundamental measurement principles and measurement endpoints of these new assays, as well as the modes of operation, analytical metrics and potential interferences, as applicable to ENM exposures. An unbiased discussion of the major technical advantages and limitations of each assay for evaluating and predicting the genotoxic potential of ENMs is also provided.
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Affiliation(s)
- Bryant C Nelson
- National Institute of Standards and Technology, Material Measurement Laboratory - Biosystems and Biomaterials Division, 100 Bureau Drive, Gaithersburg, MD 20899, USA,
| | - Christa W Wright
- Department of Environmental Health, Center for Nanotechnology and Nanotoxicology, Harvard T.H. Chan School of Public Health, 665 Huntington Avenue Building 1/Room 1309, Boston, MA 02115, USA
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka 422-8526, Japan
| | - Maria Moreno-Villanueva
- Department of Biology, University of Konstanz, Molecular Toxicology Group, D-78457 Konstanz, Germany
| | - Hanna L Karlsson
- Unit of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, 17177 Stockholm, Sweden
| | - Giel Hendriks
- Toxys, Robert Boyleweg 4, 2333 CG Leiden, The Netherlands
| | - Christopher M Sims
- National Institute of Standards and Technology, Material Measurement Laboratory - Biosystems and Biomaterials Division, 100 Bureau Drive, Gaithersburg, MD 20899, USA
| | - Neenu Singh
- Faculty of Health and Life Sciences, School of Allied Health Sciences, De Montfort University, The Gateway, Leicester LE1 9BH, UK and
| | - Shareen H Doak
- Swansea University Medical School, Institute of Life Science, Centre for NanoHealth, Swansea University Medical School, Wales SA2 8PP, UK
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25
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Zhao X, Takabayashi F, Ibuki Y. Coexposure to silver nanoparticles and ultraviolet A synergistically enhances the phosphorylation of histone H2AX. J Photochem Photobiol B 2016; 162:213-222. [PMID: 27383448 DOI: 10.1016/j.jphotobiol.2016.06.046] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Accepted: 06/25/2016] [Indexed: 11/19/2022]
Abstract
Owing to the wide application of silver nanoparticles (AgNPs), the assessment of health risks associated with their use is of great importance. In this study, we revealed that the potential genotoxicity of AgNPs was enhanced by ultraviolet A (UVA) exposure. Three cultured cell lines were treated with AgNPs, followed by exposure to UVA. AgNPs induced phosphorylation of histone H2AX (γ-H2AX) following the formation of DNA double-strand breaks (DSBs), which was synergistically enhanced by UVA exposure. Enhanced γ-H2AX was observed only in cell lines that positively took up AgNPs, and microsized Ag particles, which were difficult to incorporate into cells, showed no γ-H2AX. Incorporation of AgNPs was not increased by UVA exposure. AgNO3 treatment followed by UVA exposure also induced a marked increase in γ-H2AX, indicating that the enhanced γ-H2AX was attributed to Ag ions released from AgNPs. Ag ions reacted with the -SH group of antioxidant molecules, such as glutathione, and induced intracellular oxidative conditions. 8-Hydroxy-2'-deoxyguanosine was formed in the cells treated with AgNPs, which was augmented by UVA irradiation, suggesting that intracellular oxidation caused oxidative DNA damage, leading to the enhanced formation of DSBs and γ-H2AX. Ag has been considered a safe metal; however, our results provide important insights into the influence of sunlight on the genotoxic potency of AgNPs.
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Affiliation(s)
- Xiaoxu Zhao
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga, Shizuoka 422-8526, Japan
| | - Fumiyo Takabayashi
- School of Nursing, University of Shizuoka, 52-1 Yada, Suruga, Shizuoka 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga, Shizuoka 422-8526, Japan.
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Nakamura K, Iijima M, Ibuki Y, Kogure K, Kigure K, Nishimura T, Kanuma T. Pelvic and para-aortic lymph node mapping to diagnose micrometastasis by injection of indocyanine green in endometrial cancer. Gynecol Oncol 2016. [DOI: 10.1016/j.ygyno.2016.04.228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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27
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Zhao X, Yang G, Toyooka T, Ibuki Y. New mechanism of γ-H2AX generation: Surfactant-induced actin disruption causes deoxyribonuclease I translocation to the nucleus and forms DNA double-strand breaks. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2015; 794:1-7. [DOI: 10.1016/j.mrgentox.2015.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 09/12/2015] [Accepted: 09/18/2015] [Indexed: 10/23/2022]
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Ibuki Y, Shikata M, Toyooka T. γ-H2AX is a sensitive marker of DNA damage induced by metabolically activated 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone. Toxicol In Vitro 2015; 29:1831-8. [PMID: 26231820 DOI: 10.1016/j.tiv.2015.07.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 06/12/2015] [Accepted: 07/27/2015] [Indexed: 10/23/2022]
Abstract
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), a nicotine-derived nitrosamine, is a potent pulmonary carcinogen present in tobacco smoke. DNA adducts induced by metabolically activated NNK cause carcinogenesis; however, the DNA adducts are difficult to detect in cultured cells because of low intrinsic metabolic enzyme activity. In this study, we indirectly detected NNK-induced DNA adducts via the phosphorylation of histone H2AX (γ-H2AX) in A549 human lung adenocarcinoma epithelial cells. NNK treatment dose-dependently induced γ-H2AX. This γ-H2AX induction was suppressed by ataxia telangiectasia mutated inhibitors, suggesting that DNA double-strand breaks (DSBs) are formed during replication and repair of DNA adducts; however, DSBs could not be directly detected by biased sinusoidal field gel electrophoresis (BSFGE). CYP2A13-overexpressing cells showed prolonged γ-H2AX induction compared with control cells, and DSBs could be detected by BSFGE in CYP2A13-overexpressing cells as a clear migration of double-stranded DNA. These findings suggest that γ-H2AX is a sensitive marker of DNA adducts and provides a possible system for genotoxicity screening of chemicals such as NNK, which need metabolic activation to induce DNA damage.
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Affiliation(s)
- Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan.
| | - Mariko Shikata
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
| | - Tatsushi Toyooka
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan; National Institute of Occupational Safety and Health, Kawasaki, Japan
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Zhao X, Ibuki Y. Evaluating the toxicity of silver nanoparticles by detecting phosphorylation of histone H3 in combination with flow cytometry side-scattered light. Environ Sci Technol 2015; 49:5003-5012. [PMID: 25815977 DOI: 10.1021/acs.est.5b00542] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Post-translational modification of histones is linked to a variety of biological processes and disease states. This paper focuses on phosphorylation of histone H3 at serine 10 (p-H3S10), induced by silver nanoparticles (AgNPs) and discusses the usefulness of p-H3S10 as a marker to evaluate the toxicity of AgNPs. Cultured human cells showed remarkable p-H3S10 immediately after treatment with AgNPs but not with Ag microparticles. p-H3S10 lasts up to 24 h and strongly depends upon the cellular uptake of AgNPs. Removal of Ag ions suppressed p-H3S10, while adding an excess of Ag ions augmented p-H3S10. We expected that p-H3S10 requires two events: cellular uptake of AgNPs and continuous release of Ag ions from intracellular AgNPs. AgNPs enhanced the expression of the proto-oncogene c-jun, and p-H3S10 increased in the promoter sites of the gene, indicating that p-H3S10 might indicate a biological reaction related to carcinogenesis. We previously showed that side-scattered light from flow cytometry could be used to measure the uptake potential of nanoparticles [ Suzuki , H. ; Toyooka , T. ; Ibuki , Y. Simple and easy method to evaluate uptake potential of nanoparticles in mammalian cells using a flow cytometric light scatter analysis . Environ. Sci. Technol. 2007 , 41 ( 8 ), 3018 - 3024 ]. Our current findings suggest that p-H3S10 can be used to evaluate the toxicity of AgNPs and Ag ion release in combination with detection of side-scattered light from flow cytometry.
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Affiliation(s)
- Xiaoxu Zhao
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1, Yada, Suruga, Shizuoka, Shizuoka 422-8526, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, 52-1, Yada, Suruga, Shizuoka, Shizuoka 422-8526, Japan
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Ibuki Y, Toyooka T. Evaluation of chemical phototoxicity, focusing on phosphorylated histone H2AX. J Radiat Res 2015; 56:220-8. [PMID: 25480829 PMCID: PMC4380052 DOI: 10.1093/jrr/rru105] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/01/2014] [Accepted: 10/07/2014] [Indexed: 05/27/2023]
Abstract
Histone H2AX is a minor component of nuclear histone H2A. The phosphorylation of histone H2AX at Ser 139, termed γ-H2AX, was originally identified as an early event after the direct formation of DNA double-strand breaks (DSBs) by ionizing radiation. Now, the generation of γ-H2AX is also considered to occur in association with secondarily formed DSBs by cellular processing such as DNA replication and repair at the site of the initial damage, including DNA adducts, crosslinks, and UV-induced photolesions. Therefore, γ-H2AX is currently attracting attention as a new biomarker for detecting various genotoxic insults. We have determined the toxic impact of various environmental stresses such as chemicals, light and/or their coexposure using γ-H2AX, and found that the γ-H2AX assay exhibited high sensitivity and a low false-positive rate as a detection system of genotoxic potential. In this review, we introduced our recent findings concerning the evaluation of chemical phototoxicity, focusing on γ-H2AX.
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Affiliation(s)
- Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
| | - Tatsushi Toyooka
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
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Yoshida I, Ibuki Y. Formaldehyde-induced histone H3 phosphorylation via JNK and the expression of proto-oncogenes. Mutat Res 2014; 770:9-18. [PMID: 25771866 DOI: 10.1016/j.mrfmmm.2014.09.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2014] [Revised: 09/04/2014] [Accepted: 09/05/2014] [Indexed: 06/04/2023]
Abstract
Formaldehyde (FA) is a very reactive compound that forms DNA adducts and DNA-protein crosslinks, which are known to contribute to FA-induced mutations and carcinogenesis. Post-translational modifications to histones have recently attracted attention due to their link with cancer. In the present study, we examined histone modifications following a treatment with FA. FA significantly phosphorylated histone H3 at serine 10 (H3S10), and at serine 28 (H3S28), the time-course of which was similar to the phosphorylation of H2AX at serine 139 (γ-H2AX), a marker of DNA double strand breaks. The temporal deacetylation of H3 was observed due to the reaction of FA with the lysine residues of histones. The phosphorylation mechanism was then analyzed by focusing on H3S10. The nuclear distribution of the phosphorylation of H3S10 and γ-H2AX did not overlap, and the phosphorylation of H3S10 could not be suppressed with an inhibitor of ATM/ATR, suggesting that the phosphorylation of H3S10 was independent of the DNA damage response. ERK and JNK in the MAPK pathways were phosphorylated by the treatment with FA, in which the JNK pathway was the main target for phosphorylation. The phosphorylation of H3S10 increased at the promoter regions of c-fos and c-jun, indicating a relationship between FA-induced tumor promotion activity and phosphorylation of H3S10. These results suggested that FA both initiates and promotes cancer, as judged by an analysis of histone modifications.
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Affiliation(s)
- Ikuma Yoshida
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
| | - Yuko Ibuki
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan.
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Zhao X, Toyooka T, Ibuki Y. Silver ions enhance UVB-induced phosphorylation of histone H2AX. Environ Mol Mutagen 2014; 55:556-565. [PMID: 24838775 DOI: 10.1002/em.21875] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Revised: 04/30/2014] [Accepted: 04/30/2014] [Indexed: 06/03/2023]
Abstract
Silver (Ag) is used in a wide range of industries including healthcare, food, cosmetics, and environmental industries due to its antibacterial properties. The rapidly expanding use of Ag has raised issues concerning its toxicity in humans. However, studies investigating the effects of Ag on humans are very limited, and the combined effects of Ag and other environmental factors have not yet been determined. Ultraviolet (UV) radiation in sunlight is the most prominent and ubiquitous physical stressor in our natural environment. In this study, we investigated the genotoxic potential of combined exposure to Ag(+) (AgNO3) and UVB in the human keratinocyte cell line, HaCaT, by measuring the generation of phosphorylated histone H2AX, which is currently attracting attention as a biomarker for the detection of genotoxic insults. We found that the generation of γ-H2AX was synergistically enhanced when cells were coexposed to Ag(+) and UVB. Furthermore, we showed that the enhanced generation of γ-H2AX could be attributed to the increased formation of UVB-induced cyclobutane pyrimidine dimers and (6-4) photoproducts. These lesions, if not repaired properly, are the major causal factor for skin carcinogenesis. Our results provide an important insight into influence of Ag on the genotoxic potency of sunlight.
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Affiliation(s)
- Xiaoxu Zhao
- Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka-Shi, Shizuoka, Japan
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Fang X, Ide N, Higashi SI, Kamei Y, Toyooka T, Ibuki Y, Kawai K, Kasai H, Okamoto K, Arimoto-Kobayashi S, Negishi T. Somatic cell mutations caused by 365 nm LED-UVA due to DNA double-strand breaks through oxidative damage. Photochem Photobiol Sci 2014; 13:1338-46. [DOI: 10.1039/c4pp00148f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Kubota T, Toyooka T, Zhao X, Ibuki Y. Phosphorylation of histone H2AX generated by linear alkylbenzene sulfonates and its suppression by UVB exposure. Photochem Photobiol 2014; 90:845-52. [PMID: 24597763 DOI: 10.1111/php.12268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Accepted: 02/27/2014] [Indexed: 01/28/2023]
Abstract
We previously demonstrated that the nonionic surfactants, nonylphenol polyethoxylates (NPEOs) induced the phosphorylation of histone H2AX (γ-H2AX), accompanied by DNA double-strand breaks (DSBs), and that exposure to ultraviolet (UV) degraded NPEOs, which sometimes enhanced their DNA-damaging ability. In this study, we showed that linear alkylbenzene sulfonates (LAS), general anion surfactants, also generated DSBs with γ-H2AX, and this ability was attenuated by UVB exposure. In the human breast adenocarcinoma cell line, MCF-7, γ-H2AX was generated in a dose-dependent manner immediately after cells were treated with LAS, and this was attributed to the formation of DSBs and was independent of cell cycle phases. The ability to generate γ-H2AX was markedly reduced in LAS exposed to UVB. HPLC analysis revealed that LAS were a mixture of various alkyl chain lengths, the peaks of which were detected at individual retention times. UVB evenly decreased all peaks of LAS, without migration of peaks to other retention times, which indicated that UVB may degrade the benzene ring of LAS, but did not shorten the alkyl chains. UVB is an important environmental factor in the degradation of LAS exhibiting the ability to induce DSBs, the most serious type of DNA damage.
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Affiliation(s)
- Toru Kubota
- Institute for Environmental Sciences, University of Shizuoka, Shizuoka, Japan
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Hamai Y, Hihara J, Taomoto J, Yamakita I, Ibuki Y, Okada M. Effects of neoadjuvant chemoradiotherapy on postoperative morbidity and mortality associated with esophageal cancer. Dis Esophagus 2014; 28:358-64. [PMID: 24612033 DOI: 10.1111/dote.12207] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We compared the surgical outcomes between 114 patients who did not receive neoadjuvant therapy (group 1) and 92 others who received neoadjuvant chemoradiotherapy (nCRT) (group 2), and assessed the preoperative and surgical factors that influence postoperative morbidity to determine the impact of nCRT on morbidity and mortality after esophagectomy via cervical, right transthoracic, and abdominal approaches. The overall postoperative morbidity rates were 44.7% and 55.4% in groups 1 and 2, respectively (P = 0.13). Rates of anastomotic leak (8.8% vs. 16.3%; P = 0.10), pneumonia (9.6% vs. 13.0%; P = 0.44), recurrent nerve palsy (15.8% vs. 10.9%; P = 0.31), and all other complications did not significantly differ between the groups. Multivariable analysis revealed cervical lymph node dissection (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.01-3.84; P = 0.047) as the sole independent covariate for overall morbidity. Furthermore, a history of cardiovascular disease (OR, 2.90; 95% CI, 1.03-8.24; P = 0.045), the retrosternal reconstruction route (OR, 15.15; 95% CI, 3.56-62.50; P = 0.0002), and a longer surgical duration (OR, 1.01; 95% CI, 1.002-1.02; P = 0.01) were independent covariates for anastomotic leakage, and advanced age (OR, 1.08; 95% CI, 1.01-1.15; P = 0.02) and lower body mass index (OR, 1.16; 95% CI, 1.01-1.33; P = 0.04) were independent covariates for pneumonia. However, whether or not patients received nCRT was irrelevant. We found that nCRT is safe for three-incision esophagectomy and it does not increase the incidence of postoperative morbidity and mortality relative to esophagectomy alone.
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Affiliation(s)
- Y Hamai
- Department of Surgical Oncology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
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Ibuki Y, Toyooka T, Zhao X, Yoshida I. Cigarette sidestream smoke induces histone H3 phosphorylation via JNK and PI3K/Akt pathways, leading to the expression of proto-oncogenes. Carcinogenesis 2014; 35:1228-37. [PMID: 24398671 DOI: 10.1093/carcin/bgt492] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Post-translational modifications in histones have been associated with cancer. Although cigarette sidestream smoke (CSS) as well as mainstream smoke are carcinogens, the relationship between carcinogenicity and histone modifications has not yet been clarified. Here, we demonstrated that CSS induced phosphorylation of histones, involving a carcinogenic process. Treatment with CSS markedly induced the phosphorylation of histone H3 at serine 10 and 28 residues (H3S10 and H3S28), which was independent from the cell cycle, in the human pulmonary epithelial cell model, A549 and normal human lung fibroblasts, MRC-5 and WI-38. Using specific inhibitors and small interfering RNA, the phosphorylation of H3S10 was found to be mediated by c-jun N-terminal kinase (JNK) and phosphoinositide 3-kinase (PI3K)/Akt pathways. These pathways were different from that of the CSS-induced phosphorylation of histone H2AX (γ-H2AX) mediated by Ataxia telangiectasia-mutated (ATM) and ATM-Rad3-related (ATR) protein kinases. A chromatin immunoprecipitation assay revealed that the phosphorylation of H3S10 was increased in the promoter sites of the proto-oncogenes, c-fos and c-jun, which indicated that CSS plays a role in tumor promotion. Because the phosphorylation of H3S10 was decreased in the aldehyde-removed CSS and was significantly induced by treatment with formaldehyde, aldehydes are suspected to partially contribute to this phosphorylation. These findings suggested that any chemicals in CSS, including aldehydes, phosphorylate H3S10 via JNK and PI3K/Akt pathways, which is different from the DNA damage response, resulting in tumor promotion.
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Affiliation(s)
- Yuko Ibuki
- Institute for Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Tatsushi Toyooka
- Institute for Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Xiaoxu Zhao
- Institute for Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
| | - Ikuma Yoshida
- Institute for Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526, Japan
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Ibuki Y. Histone Modifications Induced by Chemicals and Photogenotoxicity. Genes Environ 2014. [DOI: 10.3123/jemsge.2014.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Zhao X, Toyooka T, Ibuki Y. Synergistic bactericidal effect by combined exposure to Ag nanoparticles and UVA. Sci Total Environ 2013; 458-460:54-62. [PMID: 23644279 DOI: 10.1016/j.scitotenv.2013.03.098] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Revised: 03/27/2013] [Accepted: 03/27/2013] [Indexed: 06/02/2023]
Abstract
Broad and strong antimicrobial properties of silver (Ag) have been used for biomedical applications, water treatment, etc. In this study, a synergistic antibacterial effect between Ag nanoparticles (AgNPs) and ultraviolet (UV) light was examined. AgNPs (<0.1 μm) with subsequent exposure to UVA (320-400 nm) showed pronounced toxicity in Escherichia coli, but micro-sized Ag particles (>1 μm) with UVA and AgNPs with UVB (280-325 nm) did not. As significant bactericidal activity was also exhibited by hydrogen peroxide-treated AgNPs, the surface oxidation of AgNPs caused by UVA irradiation was considered to contribute to the enhanced antibacterial effect. Although no difference in NP-incorporation rates was observed with or without the surface oxidation of AgNPs, a particle size of less than 0.1 μm was a factor for AgNPs uptake and an essential requirement for the antimicrobial function of Ag particles. Incorporated AgNPs oxidized by UVA irradiation released larger amounts of Ag ion inside cells than reduced AgNPs, which reacted with intercellular molecules having -SH groups such as glutathione. The synergistic use of AgNPs and UVA could become a powerful tool with broad antimicrobial applications.
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Affiliation(s)
- Xiaoxu Zhao
- Institute for Environmental Sciences, University of Shizuoka, Shizuoka, Japan
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Kubota T, Toyooka T, Ibuki Y. Nonylphenol Polyethoxylates Degraded by Three Different Wavelengths of UV and Their Genotoxic Change-Detected by Generation of γ-H2AX. Photochem Photobiol 2012; 89:461-7. [DOI: 10.1111/php.12002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 09/19/2012] [Indexed: 01/16/2023]
Affiliation(s)
- Toru Kubota
- Institute for Environmental Sciences; University of Shizuoka; Shizuoka-shi; Shizuoka; Japan
| | - Tatsushi Toyooka
- Institute for Environmental Sciences; University of Shizuoka; Shizuoka-shi; Shizuoka; Japan
| | - Yuko Ibuki
- Institute for Environmental Sciences; University of Shizuoka; Shizuoka-shi; Shizuoka; Japan
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Toyooka T, Kubota T, Ibuki Y. UVB irradiation changes genotoxic potential of nonylphenolpolyethoxylates— remarkable generation of γ-H2AX with degradation of chemical structure. Mutagenesis 2012; 28:7-14. [DOI: 10.1093/mutage/ges043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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41
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Toyooka T, Shinmen T, Aarts JMMJG, Ibuki Y. Dual effects of N-acetyl-L-cysteine dependent on NQO1 activity: suppressive or promotive of 9,10-phenanthrenequinone-induced toxicity. Toxicol Appl Pharmacol 2012; 264:404-12. [PMID: 22925602 DOI: 10.1016/j.taap.2012.08.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 08/13/2012] [Accepted: 08/18/2012] [Indexed: 01/10/2023]
Abstract
A typical antioxidant, N-acetyl-L-cysteine (NAC) generally protects cells from oxidative damage induced by reactive oxygen species (ROS). 9,10-Phenanthrenequinone (9,10-PQ), a major quinone in diesel exhaust particles, produces ROS in redox cycling following two-electron reduction by NAD(P)H:quinone oxidoreductase 1 (NQO1), which has been considered as a cause of its cyto- and genotoxicity. In this study, we show that NAC unexpectedly augments the toxicity of 9,10-PQ in cells with low NQO1 activity. In four human skin cell lines, the expression and the activity of NQO1 were lower than in human adenocarcinoma cell lines, A549 and MCF7. In the skin cells, the cytotoxicity of 9,10-PQ was significantly enhanced by addition of NAC. The formation of DNA double strand breaks accompanying phosphorylation of histone H2AX, was also remarkably augmented. On the other hand, the cyto- and genotoxicity were suppressed by addition of NAC in the adenocarcinoma cells. Two contrasting experiments: overexpression of NQO1 in CHO-K1 cells which originally expressed low NQO1 levels, and knock-down of NQO1 in the adenocarcinoma cell line A549 by transfection of RNAi, also showed that NAC suppressed 9,10-PQ-induced toxicity in cell lines expressing high NQO1 activity and enhanced it in cell lines with low NQO1 activity. The results suggested that dual effects of NAC on the cyto- and genotoxicity of 9,10-PQ were dependent on tissue-specific NQO1 activity.
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Affiliation(s)
- Tatsushi Toyooka
- Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
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Toduka Y, Toyooka T, Ibuki Y. Flow cytometric evaluation of nanoparticles using side-scattered light and reactive oxygen species-mediated fluorescence-correlation with genotoxicity. Environ Sci Technol 2012; 46:7629-36. [PMID: 22703531 DOI: 10.1021/es300433x] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We recently clarified that the side-scatter(ed) light (SSC) of flow cytometry (FCM) could be used as a guide to measure the uptake potential of nanoparticles [ Suzuki et al. Environ. Sci. Technol. 2007 , 41 , 3018 - 3024 ]. In this paper, the method was improved so as to be able to determine simultaneously the uptake potential of nanoparticles and the production of reactive oxygen species (ROS), and correlations with genotoxicity were evaluated. In the FCM analysis, SSC and fluorescence of 6-carboxy-2,7'-diclorodihydrofluorescein diacetate, di(acetoxy ester) based on ROS production were concurrently detected after treatments with ZnO, CuO, Fe(3)O(4), TiO(2), and Ag nanoparticles. The ZnO and CuO nanoparticles caused high ROS production, which was more significant in the cells with higher SSC intensity. The increase of SSC intensity was more significant for TiO(2) than ZnO and CuO, whereas ROS production was higher for ZnO and CuO than TiO(2), suggesting that the extent of ROS production based on the uptake of nanoparticles differed with each kind of nanoparticle. ROS production was correlated with generation of the phosphorylated histone H2AX (γ-H2AX), a marker of DNA damage, and an antioxidant, n-acetylcysteine, could partially suppress the γ-H2AX. This method makes it possible to predict not only uptake potential but also genotoxicity.
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Affiliation(s)
- Yousuke Toduka
- Institute for Environmental Sciences, University of Shizuoka , 52-1 Yada, Suruga-ku, Shizuoka-shi, Shizuoka 422-8526, Japan
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Toyooka T, Amano T, Ibuki Y. Titanium dioxide particles phosphorylate histone H2AX independent of ROS production. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2012; 742:84-91. [DOI: 10.1016/j.mrgentox.2011.12.015] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 12/09/2011] [Accepted: 12/18/2011] [Indexed: 11/15/2022]
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Nunoshiba T, Kuraoka I, Ibuki Y, Narumi I. “Challenge to Conquer Cancer—New Trends in Mutation Research” JEMS Open Symposium 2011. Genes Environ 2012. [DOI: 10.3123/jemsge.34.55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Abstract
The uptake of nanoparticles by cells is an important factor to assess nanotoxicity. In general, the nanoparticles taken up by the cells have been identified by transmission electron microscope, inductively coupled plasma mass spectrometry, etc.; however, the methods required an immense amount of time and effort. Flow cytometry (FCM) has been used and developed in the fields of biochemistry and clinical hematology, and has advantages to analyze thousands of cells in seconds. We recently clarified that the side-scatter(ed) light of FCM could be used as a guide to measure uptake potential of nanoparticles. Here, we describe the protocol for screening of the uptake potential of nanoparticles using FCM.
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Affiliation(s)
- Yuko Ibuki
- Institute for Environmental Sciences, University of Shizuoka, Shizuoka-shi, Japan.
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Toyooka T, Kubota T, Ibuki Y. Nonylphenol polyethoxylates induce phosphorylation of histone H2AX. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2012; 741:57-64. [DOI: 10.1016/j.mrgentox.2011.10.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/02/2011] [Accepted: 10/09/2011] [Indexed: 10/15/2022]
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Tsutani Y, Ibuki Y, Ikeda T, Miyata Y, Nakayama H, Okada M. Role of solid tumor size compared with whole tumor size to predict pathologic malignant grade or prognosis in clinical stage IA lung adenocarcinoma: A multicenter study. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.7058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Abstract
Several light-absorbing chemicals are known to show phototoxic effects involving many kinds of DNA damage, and are suspected of initiating skin cancer. In this study, we clarified that phosphorylated histone H2AX (γ-H2AX) (phosphorylated histone H2AX), which was produced with the induction of DNA double-strand breaks, is a sensitive photogenotoxic marker. The immortal human keratinocyte line HaCaT was treated with a library of 11 chemicals (including known strong and weak phototoxic chemicals, and nonphototoxic chemicals) and/or UVA exposure. γ-H2AX was generated after treatments with all phototoxic chemicals and UVA. The limit of detection using γ-H2AX was 100-1,000 times lower than that using cell viability and DNA gel electrophoresis. γ-H2AX was not generated following treatments with nonphototoxic chemicals and UVA. These results indicated that γ-H2AX is a powerful tool for detecting chemical photogenotoxicity.
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Affiliation(s)
- Tatsushi Toyooka
- Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka, Japan
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Ohnuki G, Toyooka T, Ibuki Y. UVB in solar-simulated light causes formation of BaP-photoproducts capable of generating phosphorylated histone H2AX. Mutation Research/Genetic Toxicology and Environmental Mutagenesis 2010; 702:70-7. [DOI: 10.1016/j.mrgentox.2010.07.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/31/2010] [Accepted: 07/04/2010] [Indexed: 01/20/2023]
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Teranishi M, Toyooka T, Ohura T, Masuda S, Ibuki Y. Benzo[a]pyrene exposed to solar-simulated light inhibits apoptosis and augments carcinogenicity. Chem Biol Interact 2010; 185:4-11. [DOI: 10.1016/j.cbi.2010.02.044] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2009] [Revised: 02/25/2010] [Accepted: 02/25/2010] [Indexed: 11/16/2022]
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