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Zhou J, Wang X, Jia M, He X, Pan H, Chen J. Ultrafast spectroscopy study of DNA photophysics after proflavine intercalation. J Chem Phys 2024; 160:124305. [PMID: 38526107 DOI: 10.1063/5.0194608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 03/06/2024] [Indexed: 03/26/2024] Open
Abstract
Proflavine (PF), an acridine DNA intercalating agent, has been widespread applied as an anti-microbial and topical antiseptic agent due to its ability to suppress DNA replication. On the other hand, various studies show that PF intercalation to DNA can increase photogenotoxicity and has potential chances to induce carcinomas of skin appendages. However, the effects of PF intercalation on the photophysical and photochemical properties of DNA have not been sufficiently explored. In this study, the excited state dynamics of the PF intercalated d(GC)9 • d(GC)9 and d(AT)9 • d(AT)9 DNA duplex are investigated in an aqueous buffer solution. Under 267 nm excitation, we observed ultrafast charge transfer (CT) between PF and d(GC)9 • d(GC)9 duplex, generating a CT state with an order of magnitude longer lifetime compared to that of the intrinsic excited state reported for the d(GC)9 • d(GC)9 duplex. In contrast, no excited state interaction was detected between PF and d(AT)9 • d(AT)9. Nevertheless, a localized triplet state with a lifetime over 5 µs was identified in the PF-d(AT)9 • d(AT)9 duplex.
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Affiliation(s)
- Jie Zhou
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Xueli Wang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Menghui Jia
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Xiaoxiao He
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Haifeng Pan
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200241, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi 030006, China
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A State-of-the-Art Review on the Alternatives to Animal Testing for the Safety Assessment of Cosmetics. COSMETICS 2022. [DOI: 10.3390/cosmetics9050090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Almost a decade after the stipulated deadline in the 7th amendment to the EU Cosmetics Directive, which bans the marketing of animal-tested cosmetics in the EU from 2013, animal experimentation for cosmetic-related purposes remains a topic of animated debate. Cosmetic industry continues to be scrutinised for the practice, despite its leading role in funding and adopting innovation in this field. This paper aims to provide a state-of-the-art review of the field on alternative testing methods, also known as New Approach Methodologies (NAMs), with the focus on assessing the safety of cosmetic ingredients and products. It starts with innovation drivers and global regulatory responses, followed by an extensive, endpoint-specific overview of accepted/prospective NAMs. The overview covers main developments in acute toxicity, skin corrosion/irritation, serious eye damage/irritation, skin sensitisation, repeated dose toxicity, reproductive toxicity/endocrine disruption, mutagenicity/genotoxicity, carcinogenicity, photo-induced toxicity, and toxicokinetics. Specific attention was paid to the emerging in silico methodology. This paper also provides a brief overview of the studies on public perception of animal testing in cosmetics. It concludes with a view that educating consumers and inviting them to take part in advocacy could be an effective tool to achieve policy changes, regulatory acceptance, and investment in innovation.
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Pistollato F, Madia F, Corvi R, Munn S, Grignard E, Paini A, Worth A, Bal-Price A, Prieto P, Casati S, Berggren E, Bopp SK, Zuang V. Current EU regulatory requirements for the assessment of chemicals and cosmetic products: challenges and opportunities for introducing new approach methodologies. Arch Toxicol 2021; 95:1867-1897. [PMID: 33851225 PMCID: PMC8166712 DOI: 10.1007/s00204-021-03034-y] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 03/18/2021] [Indexed: 12/28/2022]
Abstract
The EU Directive 2010/63/EU on the protection of animals used for scientific purposes and other EU regulations, such as REACH and the Cosmetic Products Regulation advocate for a change in the way toxicity testing is conducted. Whilst the Cosmetic Products Regulation bans animal testing altogether, REACH aims for a progressive shift from in vivo testing towards quantitative in vitro and computational approaches. Several endpoints can already be addressed using non-animal approaches including skin corrosion and irritation, serious eye damage and irritation, skin sensitisation, and mutagenicity and genotoxicity. However, for systemic effects such as acute toxicity, repeated dose toxicity and reproductive and developmental toxicity, evaluation of chemicals under REACH still heavily relies on animal tests. Here we summarise current EU regulatory requirements for the human health assessment of chemicals under REACH and the Cosmetic Products Regulation, considering the more critical endpoints and identifying the main challenges in introducing alternative methods into regulatory testing practice. This supports a recent initiative taken by the International Cooperation on Alternative Test Methods (ICATM) to summarise current regulatory requirements specific for the assessment of chemicals and cosmetic products for several human health-related endpoints, with the aim of comparing different jurisdictions and coordinating the promotion and ultimately the implementation of non-animal approaches worldwide. Recent initiatives undertaken at European level to promote the 3Rs and the use of alternative methods in current regulatory practice are also discussed.
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Affiliation(s)
- Francesca Pistollato
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Federica Madia
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Raffaella Corvi
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Sharon Munn
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Elise Grignard
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Alicia Paini
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Andrew Worth
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Anna Bal-Price
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Pilar Prieto
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Silvia Casati
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Elisabet Berggren
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Stephanie K Bopp
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy
| | - Valérie Zuang
- Directorate F-Health, Consumers and Reference Materials, Unit F3 Chemicals Safety and Alternative Methods, European Commission, Joint Research Centre (JRC), Via E. Fermi, 2749. TP126, 21027, Ispra, VA, Italy.
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4
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Paiva JP, Diniz RR, Leitão AC, Cabral LM, Fortunato RS, Santos BAMC, de Pádula M. Insights and controversies on sunscreen safety. Crit Rev Toxicol 2020; 50:707-723. [PMID: 33064037 DOI: 10.1080/10408444.2020.1826899] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Although sunlight provides several benefits, ultraviolet (UV) radiation plays an important role in the development of various skin damages such as erythema, photoaging, and photocarcinogenesis. Despite cells having endogenous defense systems, damaged DNA may not be efficiently repaired at chronic exposure. In this sense, it is necessary to use artificial defense strategies such as sunscreen formulations. UV filters should scatter, reflect, or absorb solar UV radiation in order to prevent direct or indirect DNA lesions. However, the safety of UV filters is a matter of concern due to several controversies reported in literature, such as endocrine alterations, allergies, increased oxidative stress, phototoxic events, among others. Despite these controversies, the way in which sunscreens are tested is essential to ensure safety. Sunscreen regulation includes mandatory test for phototoxicity, but photogenotoxicity testing is not recommended as a part of the standard photosafety testing program. Although available photobiological tests are still the first approach to assess photosafety, they are limited. Some existing tests do not always provide reliable results, mainly due to limitations regarding the nature of the assessed phototoxic effect, cell UV sensitivity, and the irradiation protocols. These aspects bring queries regarding the safety of sunscreen wide use and suggest the demand for the development of robust and efficient in vitro screening tests to overcome the existing limitations. In this way, Saccharomyces cerevisiae has stood out as a promising model to fill the gaps in photobiology and to complete the mandatory tests enabling a more extensive and robust photosafety assessment.
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Affiliation(s)
- Juliana P Paiva
- Laboratório de Microbiologia Industrial e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Raiane R Diniz
- Laboratório de Microbiologia Industrial e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.,Laboratório de Tecnologia Industrial Farmacêutica (LabTIF), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alvaro C Leitão
- Laboratório de Radiobiologia Molecular (Radmol), Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lucio M Cabral
- Laboratório de Tecnologia Industrial Farmacêutica (LabTIF), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo S Fortunato
- Laboratório de Fisiologia e Sinalização Redox, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bianca A M C Santos
- Laboratório de Planejamento Farmacêutico e Simulação Computacional (LaPFarSC), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcelo de Pádula
- Laboratório de Microbiologia Industrial e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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5
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Dwivedi DK, Jena G, Kumar V. Dimethyl fumarate protects thioacetamide-induced liver damage in rats: Studies on Nrf2, NLRP3, and NF-κB. J Biochem Mol Toxicol 2020; 34:e22476. [PMID: 32060995 DOI: 10.1002/jbt.22476] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 12/17/2019] [Accepted: 02/06/2020] [Indexed: 12/30/2022]
Abstract
The present study was designed to investigate the hepatoprotective potential of dimethyl fumarate (DMF) against thioacetamide (TAA)-induced liver damage. Wistar rats were treated with DMF (12.5, 25, and 50 mg/kg/day, orally) and TAA (200 mg/kg intraperitoneally, every third day) for 6 consecutive weeks. TAA exposure significantly reduced body weight, increased liver weight and index, and intervention with DMF did not ameliorate these parameters. DMF treatment significantly restored TAA-induced increase in the levels of aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transferase, total bilirubin, uric acid, malondialdehyde, reduced glutathione, and histopathological findings such as inflammatory cell infiltration, deposition of collagen, necrosis, and bridging fibrosis. DMF treatment significantly ameliorated TAA-induced hepatic stellate cell activation, increase in inflammatory cascade markers (NACHT, LRR, and PYD domains-containing protein 3; NLRP3, apoptosis-associated speck like protein containing a caspase recruitment domain; ASC, caspase-1, nuclear factor-kappa B; NF-κB, interleukin-6), fibrogenic makers (α-smooth muscle actin; ɑ-SMA, transforming growth factor; TGF-β1, fibronectin, collagen 1) and antioxidant markers (nuclear factor (erythroid-derived 2)-like factor 2; Nrf2, superoxide dismutase-1; SOD-1, catalase). The present findings concluded that DMF protects against TAA-induced hepatic damage mediated through the downregulation of inflammatory cascades and upregulation of antioxidant status.
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Affiliation(s)
- Durgesh K Dwivedi
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Punjab, India
| | - Gopabandhu Jena
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Punjab, India
| | - Vinod Kumar
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, SAS Nagar, Punjab, India
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6
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Diniz RR, Paiva JP, Aquino RM, Gonçalves TCW, Leitão AC, Santos BAMC, Pinto AV, Leandro KC, de Pádula M. Saccharomyces cerevisiae strains as bioindicators for titanium dioxide sunscreen photoprotective and photomutagenic assessment. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2019; 198:111584. [PMID: 31434036 DOI: 10.1016/j.jphotobiol.2019.111584] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 04/01/2019] [Accepted: 08/07/2019] [Indexed: 11/15/2022]
Abstract
Although several short-term assays are available for cosmetic photosafety assessment, cell models are usually highly sensitive to UV radiation, tending to overestimate both phototoxic and photomutagenic risks. In addition, these assays are performed with UV doses/fluences that do not correspond to actual environmental conditions. In this sense, Saccharomyces cerevisiae has already proved to be an interesting tool to predict photomutagenic potential of several compounds, including sunscreens. Yeast can support environmental UVB doses compatible with human daily sunlight exposure, allowing the use of irradiation sources to faithfully mimic the external conditions of ambient sunlight. Herein, we used a set of S. cerevisiae mutant strains sensitive to UVA, UVB and Solar Simulated Light sources in order to evaluate their potential as bioindicators for sunscreen development. The bioindicator potential of the strains was tested with the widely-used titanium dioxide inorganic sunscreen. The AWP001 (yno1) and LPW002 (ogg1yno1) strains obtained in this study stood out as promising experimental tools for the validation of this assay. Overall, our results evidenced a set of S. cerevisiae strains particularly useful for evaluating both photoprotective (efficacy) and photo/antiphotomutagenic (safety) potential of UV filters, meeting the industries and regulatory agencies demand for robust and efficient in vitro screening tests.
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Affiliation(s)
- Raiane R Diniz
- Instituto Nacional de Controle de Qualidade em Saúde (INCQS), Fundação Oswaldo Cruz, Rio de Janeiro 21040-900, Brazil; Laboratório de Microbiologia e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Juliana P Paiva
- Laboratório de Microbiologia e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Renan M Aquino
- Laboratório de Microbiologia e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Tula C W Gonçalves
- Laboratório de Microbiologia e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Alvaro C Leitão
- Instituto de Biofísica Carlos Chagas Filho, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Bianca Aloise M C Santos
- Laboratório de Planejamento Farmacêutico e Simulação Computacional (LaPFarSC), Faculdade de Farmácia, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil
| | - Alicia V Pinto
- Instituto Nacional de Controle de Qualidade em Saúde (INCQS), Fundação Oswaldo Cruz, Rio de Janeiro 21040-900, Brazil
| | - Katia C Leandro
- Instituto Nacional de Controle de Qualidade em Saúde (INCQS), Fundação Oswaldo Cruz, Rio de Janeiro 21040-900, Brazil
| | - Marcelo de Pádula
- Laboratório de Microbiologia e Avaliação Genotóxica (LAMIAG), Faculdade de Farmácia, CCS, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21949-900, Brazil.
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Liebsch M, Spielmann H, Pape W, Krul C, Deguercy A, Eskes C. 3.8. UV-induced Effects. Altern Lab Anim 2019; 33 Suppl 1:131-46. [PMID: 16194146 DOI: 10.1177/026119290503301s14] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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8
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Fernandes A, Mazzei J, Evangelista H, Marques M, Ferraz E, Felzenszwalb I. Protection against UV-induced oxidative stress and DNA damage by Amazon moss extracts. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 183:331-341. [PMID: 29758545 DOI: 10.1016/j.jphotobiol.2018.04.038] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 03/20/2018] [Accepted: 04/25/2018] [Indexed: 12/13/2022]
Abstract
Amazon mosses, such as Holomitriopsis laevifolia and Leucobryum sp. are naturally exposed to high levels of solar ultraviolet (UV) radiation. Theoretically, under environmental stress conditions these mosses have developed protective chemical and metabolic strategies against UV damage, by way of biosynthesis of secondary metabolites, such as flavonoids. The present paper aimed to evaluate the free-radical scavenging activity, and the photoprotective, mutagenic and photomutagenic potencies of the methanolic (ME), aqueous (AE), hydroalcoholic (HE), ethanolic (EE) extracts of H. laevifolia and Leucobryum sp. The phenolic contents were evaluated by spectrophotometry and by High-Performance Liquid Chromatography (HPLC). The present findings showed that the AE and HE of H. laevifolia and the AE of Leucobryum sp. presented the highest phenolic contents. The HPLC analysis indicated the presence mainly of phenolic and cinnamic acids, flavonols, flavones and flavanones. The AE and EE of H. laevifolia and the AE and HE of Leucobryum sp. efficiently scavenged the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical. All extracts showed significant values of in vitro Sun Protection Factor alone, and HE of Leucobryum sp. showed a synergistic effect in association with benzophenone-3. None of the extracts induced mutagenicity in the auxotrophic strains for histidine of Salmonella typhimurium, and photomutagenicity of the TA102 and TA104 strains was not detected after exposure to UV-A radiation. Besides, all extracts showed photoprotective activity against UV-A radiation for the TA104 strain, including synergistic protection in association with BP-3. Thus, the constituents in H. Laevifolia and Leucobryum sp. could be good candidates for cosmetic and dermatological applications, particularly in association with synthetic UV filters, since the concentration of the filters in the final product could be reduced.
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Protection against UV-induced toxicity and lack of mutagenicity of Antarctic Sanionia uncinata. Toxicology 2017; 376:126-136. [DOI: 10.1016/j.tox.2016.05.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/15/2016] [Accepted: 05/24/2016] [Indexed: 11/20/2022]
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10
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Oda Y. Development and progress for three decades in umu test systems. Genes Environ 2016; 38:24. [PMID: 27980699 PMCID: PMC5131509 DOI: 10.1186/s41021-016-0054-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2016] [Accepted: 07/27/2016] [Indexed: 11/10/2022] Open
Abstract
Umu test have been widely used to predict the detection and assessment of DNA- damaging chemicals in environmental genotoxicity field for three decades. This test system is more useful with respect to simplicity, sensitivity, rapidity, and reproducibility. A review of the literature on the development of the umu test is presented in this article. The contents of this article are included a description of numerous data using the umu test. This test have been fully evaluated and used in many directions. Different genetically engineered umu systems introducing bacterial and rat or human drug metabolizing enzymes into the umu tester strains, have been successfully established and are considered as useful tools for genotoxicity assays to study the mechanisms of biotransformation in chemical carcinogenesis. Actually, we developed that two types of bacterial metabolizing enzymes and 4 types of rat and human metabolizing enzyme DNAs are expressed in these strains such as nitroreductase and O-acetyltransferase, cytochrome P450, N-acetyltransferases, sulfotransferases, and glutathione S-transferases, respectively. Due to increasing numbers of minute environmental samples and new pharmaceuticals, a high-throughput umu test system using Salmonella typhimurium TA1535/pSK1002, NM2009, and NM3009 strains provides a useful for these genotoxicity screening. I also briefly describe the first attempts to incorporate such umu tester strain into photo-genotoxicity test.
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Affiliation(s)
- Yoshimitsu Oda
- Institute of Life and Environmental Sciences, Osaka Shin-Ai College, 6-2-28 Tsurumi, Tsurumi-ku, Osaka 538-0053 Japan
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11
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Mutagenic and carcinogenic structural alerts and their mechanisms of action. Arh Hig Rada Toksikol 2016; 67:169-182. [DOI: 10.1515/aiht-2016-67-2801] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 09/01/2016] [Indexed: 12/24/2022] Open
Abstract
Abstract
Knowing the mutagenic and carcinogenic properties of chemicals is very important for their hazard (and risk) assessment. One of the crucial events that trigger genotoxic and sometimes carcinogenic effects is the forming of adducts between chemical compounds and nucleic acids and histones. This review takes a look at the mechanisms related to specific functional groups (structural alerts or toxicophores) that may trigger genotoxic or epigenetic effects in the cells. We present up-to-date information about defined structural alerts with their mechanisms and the software based on this knowledge (QSAR models and classification schemes).
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12
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Onoue S, Ohtake H, Suzuki G, Seto Y, Nishida H, Hirota M, Ashikaga T, Kouzuki H. Comparative study on prediction performance of photosafety testing tools on photoallergens. Toxicol In Vitro 2016; 33:147-52. [DOI: 10.1016/j.tiv.2016.03.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 01/21/2016] [Accepted: 03/06/2016] [Indexed: 10/22/2022]
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13
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Singh J, Dwivedi A, Mujtaba SF, Singh KP, Pal MK, Chopra D, Goyal S, Srivastav AK, Dubey D, Gupta SK, Haldar C, Ray RS. RETRACTED: Ambient UV-B exposure reduces the binding of ofloxacin with bacterial DNA gyrase and induces DNA damage mediated apoptosis. Int J Biochem Cell Biol 2016; 73:111-126. [DOI: 10.1016/j.biocel.2016.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 12/02/2015] [Accepted: 01/05/2016] [Indexed: 01/16/2023]
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14
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Morkunas V, Gabryte E, Vengris M, Danielius R, Danieliene E, Ruksenas O. DNA Damage in Bone Marrow Cells Induced by Femtosecond and Nanosecond Ultraviolet Laser Pulses. Photomed Laser Surg 2015; 33:585-91. [DOI: 10.1089/pho.2015.3897] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Vaidotas Morkunas
- Department of Botany and Genetics, Faculty of Natural Sciences, Vilnius University, Vilnius, Lithuania
| | - Egle Gabryte
- Light Conversion Ltd., Vilnius, Lithuania
- Department of Quantum Electronics, Faculty of Physics, Vilnius University, Vilnius, Lithuania
| | - Mikas Vengris
- Department of Quantum Electronics, Faculty of Physics, Vilnius University, Vilnius, Lithuania
| | | | - Egle Danieliene
- Joint Stock Company Akiu Gydytoju Praktika, Vilnius, Lithuania
| | - Osvaldas Ruksenas
- Department of Neurobiology and Biophysics, Faculty of Natural Sciences, Vilnius University, Vilnius, Lithuania
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15
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Čižeková L, Grolmusová A, Ipóthová Z, Barbieriková Z, Brezová V, Hunáková L, Imrich J, Janovec L, Dovinová I, Paulíková H. Novel 3,6-bis(imidazolidine)acridines as effective photosensitizers for photodynamic therapy. Bioorg Med Chem 2014; 22:4684-93. [DOI: 10.1016/j.bmc.2014.07.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 07/01/2014] [Accepted: 07/09/2014] [Indexed: 01/28/2023]
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16
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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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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17
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Methods for Using the Mouse Lymphoma Assay to Screen for Chemical Mutagenicity and Photo-Mutagenicity. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2014. [DOI: 10.1007/978-1-62703-742-6_34] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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18
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Onoue S, Hosoi K, Toda T, Takagi H, Osaki N, Matsumoto Y, Kawakami S, Wakuri S, Iwase Y, Yamamoto T, Nakamura K, Ohno Y, Kojima H. Intra-/inter-laboratory validation study on reactive oxygen species assay for chemical photosafety evaluation using two different solar simulators. Toxicol In Vitro 2013; 28:515-23. [PMID: 24384453 DOI: 10.1016/j.tiv.2013.11.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 11/14/2013] [Indexed: 10/25/2022]
Abstract
A previous multi-center validation study demonstrated high transferability and reliability of reactive oxygen species (ROS) assay for photosafety evaluation. The present validation study was undertaken to verify further the applicability of different solar simulators and assay performance. In 7 participating laboratories, 2 standards and 42 coded chemicals, including 23 phototoxins and 19 non-phototoxic drugs/chemicals, were assessed by the ROS assay using two different solar simulators (Atlas Suntest CPS series, 3 labs; and Seric SXL-2500V2, 4 labs). Irradiation conditions could be optimized using quinine and sulisobenzone as positive and negative standards to offer consistent assay outcomes. In both solar simulators, the intra- and inter-day precisions (coefficient of variation; CV) for quinine were found to be below 10%. The inter-laboratory CV for quinine averaged 15.4% (Atlas Suntest CPS) and 13.2% (Seric SXL-2500V2) for singlet oxygen and 17.0% (Atlas Suntest CPS) and 7.1% (Seric SXL-2500V2) for superoxide, suggesting high inter-laboratory reproducibility even though different solar simulators were employed for the ROS assay. In the ROS assay on 42 coded chemicals, some chemicals (ca. 19-29%) were unevaluable because of limited solubility and spectral interference. Although several false positives appeared with positive predictivity of ca. 76-92% (Atlas Suntest CPS) and ca. 75-84% (Seric SXL-2500V2), there were no false negative predictions in both solar simulators. A multi-center validation study on the ROS assay demonstrated satisfactory transferability, accuracy, precision, and predictivity, as well as the availability of other solar simulators.
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Affiliation(s)
- Satomi Onoue
- Department of Pharmacokinetics and Pharmacodynamics, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
| | - Kazuhiro Hosoi
- Non-Clinical Research Group, Ophthalmic Research and Development Center, Santen Pharmaceutical Co., Ltd., 8916-16 Takayama-cho, Ikoma, Nara 630-0101, Japan
| | - Tsuguto Toda
- Drug Developmental Research Laboratories, Shionogi & Co., Ltd., 3-1-1 Futaba-cho, Toyonaka, Osaka 561-0825, Japan
| | - Hironori Takagi
- Research Center, Taisho Pharmaceutical Co., Ltd., 1-403, Yoshino-cho, Kita-ku, Saitama 331-9530, Japan
| | - Naoto Osaki
- Research Center, Taisho Pharmaceutical Co., Ltd., 1-403, Yoshino-cho, Kita-ku, Saitama 331-9530, Japan
| | - Yasuhiro Matsumoto
- Safety Research Department, ASKA Pharmaceutical Co., Ltd., 5-36-1, Shimosakunobe, Takatsu-ku, Kawasaki, Kanagawa 213-8522, Japan
| | - Satoru Kawakami
- Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation, 632-1 Mifuku Izunokuni-shi, Shizuoka 410-2321, Japan
| | - Shinobu Wakuri
- Laboratory of Cell Toxicology, Hatano Research Institute, Food and Drug Safety Center, 729-5 Ochiai, Hadano, Kanagawa 257-8523, Japan
| | - Yumiko Iwase
- Safety Research Laboratories, Mitsubishi Tanabe Pharma Corporation, 1-1-1, Kazusakamatari, Kisarazu, Chiba 292-0818, Japan
| | - Toshinobu Yamamoto
- Safety Research Laboratories, Mitsubishi Tanabe Pharma Corporation, 2-2-50, Kawaguchi, Toda-shi, Saitama 335-8505, Japan
| | - Kazuichi Nakamura
- Product Development Regulatory Affairs Department, Shionogi & Co., Ltd., 2-17-5 Shibuya, Shibuya-ku, Tokyo 150-8673, Japan
| | - Yasuo Ohno
- National Institute of Health Sciences (NIHS), 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan
| | - Hajime Kojima
- Japanese Center for the Validation of Alternative Methods (JaCVAM), National Institute of Health Sciences (NIHS), 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan
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19
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Onoue S, Suzuki G, Kato M, Hirota M, Nishida H, Kitagaki M, Kouzuki H, Yamada S. Non-animal photosafety assessment approaches for cosmetics based on the photochemical and photobiochemical properties. Toxicol In Vitro 2013; 27:2316-24. [DOI: 10.1016/j.tiv.2013.10.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 09/15/2013] [Accepted: 10/03/2013] [Indexed: 11/16/2022]
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20
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Vasquez MI, Garcia-Käufer M, Hapeshi E, Menz J, Kostarelos K, Fatta-Kassinos D, Kümmerer K. Chronic ecotoxic effects to Pseudomonas putida and Vibrio fischeri, and cytostatic and genotoxic effects to the hepatoma cell line (HepG2) of ofloxacin photo(cata)lytically treated solutions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2013; 450-451:356-365. [PMID: 22743217 DOI: 10.1016/j.scitotenv.2012.05.096] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 05/30/2012] [Accepted: 05/30/2012] [Indexed: 06/01/2023]
Abstract
Ofloxacin (OFL), a broad-spectrum and widespread-used photolabile fluoroquinolone, is frequently found in treated wastewaters, aquatic and terrestrial ecosystems leading to increasing concern during the past decades regarding its effects to the environment and human health. The elimination of OFL and other xenobiotics by the application of advanced oxidation processes using photolytic (PL) and photocatalytic (PC) treatments seems promising. However, an integrated assessment scheme is needed, in which, not only the removal of the parent compound, but also the effects of the photo-transformation products (PTPs) are investigated. For this purpose, in the present study, a chronic ecotoxic assessment using representative bacteria of marine and terrestrial ecosystems and a cytostatic and genotoxic evaluation using hepatoma cell line were performed. PL and PC treatments of OFL were applied using UV radiation. The photo-transformation of OFL during the treatments was monitored by DOC measurements and UPLC-MS/MS analysis. The chronic ecotoxicity of OFL and treated samples was evaluated using Pseudomonas putida and Vibrio fischeri; whereas the cytostasis and genotoxicity were estimated by the cytokinesis-block micronucleus assay (CBMN). The main results suggest that photo-transformation of OFL took place during these treatments since the concentration of OFL decreased when the irradiation time increased, as quantified by UPLC-MS/MS analysis, and this was not coupled with an analogous DOC removal. Furthermore, nine compounds were identified as probable PTPs formed through piperazinyl dealkylation and decarboxylation. The ecotoxicity of treated solutions to the bacteria studied decreased while the cytostasis to the hepatoma cell line remained at low levels during both treatments. However, the genotoxicity to the hepatoma cell line demonstrated a different pattern in which treated samples induced a greater number of MNi for the 4-16 min of irradiation (p<0.05) during both treatments. After 64 min of irradiation, the effects decreased to non genotoxic levels (p<0.05). These findings suggest that UV radiation for various treatment processes (catalytic or not), such as disinfection, may create genotoxic by-products. Therefore, in relevant technical applications, the residence time during treatment should receive special attention.
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Affiliation(s)
- M I Vasquez
- University of Cyprus, Department of Civil and Environmental Engineering, University of Cyprus, 75 Kallipoleos Street, 1678 Nicosia, Cyprus
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21
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Seto Y, Inoue R, Kato M, Yamada S, Onoue S. Photosafety assessments on pirfenidone: Photochemical, photobiological, and pharmacokinetic characterization. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2013; 120:44-51. [DOI: 10.1016/j.jphotobiol.2013.01.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 01/16/2013] [Accepted: 01/16/2013] [Indexed: 10/27/2022]
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22
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Abstract
UV is the most abundant human carcinogen, and protection from extensive exposure to it is a widespread human health issue. The use of chemicals (sunscreens) for protection is intuitive and efficacious. However, these chemicals may become activated to reactive intermediates when absorbing energy from UV, thus producing damage themselves, which may manifest itself in phototoxic, photoallergenic or photocarcinogenic reactions in humans. The development of safe sunscreens for humans is of high interest. Similar issues have been observed for some therapeutically used principles such as PUVA therapy for psoriasis or porphyrins for phototherapy of human cancers. Photoactivation has also been reported as a side effect of various pharmaceuticals such as the antibacterial fluoroquinolones. In this context, the authors have been involved over more than 20 years in the development and refinement of assays to test for photomutagenicity as an unwanted side effect of UV-mediated activation of such chemicals for cosmetic or pharmaceutical use. The initial years of great hopes for simple mammalian cell-based assays for photomutagenicity to screen out substances of concern for human use were followed by many years of collaborative trials to achieve standardization. However, it is now realized that this topic, albeit of human safety relevance, is highly complex and subject to many artificial modifiers, especially in vitro in mammalian cell culture. Thus, it is not really suitable for being engineered into a general testing framework within cosmetic or pharmaceutical testing guidelines. Much knowledge has been generated over the years to arrive at the conclusion that yes, photomutagenicity does exist with the use of chemicals, but how to best test for it will require a sophisticated case-by-case approach. Moreover, in comparison to the properties and risks of exposure to UV itself, it remains a comparatively minor human safety risk to address. In considering risks and benefits, we should also acknowledge beneficial effects of UV on human health, including an essential role in the production of Vitamin D. Thus, the interrelationships between UV, chemicals and human health remain a fascinating topic of research.
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Affiliation(s)
- Lutz Müller
- F. Hoffmann-La Roche Ltd., Basel, Switzerland.
| | - Elmar Gocke
- F. Hoffmann-La Roche Ltd., Basel, Switzerland
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23
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Paim CS, Nogueira DR, Mitjans M, Ramos Lopez D, de Lapuente Perez J, Steppe M, Schapoval EES, Vinardell MP. Biological safety studies of gemifloxacin mesylate and related substances. Photochem Photobiol Sci 2013; 12:805-12. [DOI: 10.1039/c3pp25369d] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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24
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Guérard M, Zeller A, Singer T, Gocke E. In vitro genotoxicity of neutral red after photo-activation and metabolic activation in the Ames test, the micronucleus test and the comet assay. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2012; 746:15-20. [DOI: 10.1016/j.mrgentox.2012.01.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 10/25/2011] [Accepted: 01/07/2012] [Indexed: 10/28/2022]
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25
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Onoue S, Hosoi K, Wakuri S, Iwase Y, Yamamoto T, Matsuoka N, Nakamura K, Toda T, Takagi H, Osaki N, Matsumoto Y, Kawakami S, Seto Y, Kato M, Yamada S, Ohno Y, Kojima H. Establishment and intra-/inter-laboratory validation of a standard protocol of reactive oxygen species assay for chemical photosafety evaluation. J Appl Toxicol 2012; 33:1241-50. [PMID: 22696462 DOI: 10.1002/jat.2776] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 04/16/2012] [Accepted: 04/16/2012] [Indexed: 11/07/2022]
Abstract
A reactive oxygen species (ROS) assay was previously developed for photosafety evaluation of pharmaceuticals, and the present multi-center study aimed to establish and validate a standard protocol for ROS assay. In three participating laboratories, two standards and 42 coded chemicals, including 23 phototoxins and 19 nonphototoxic drugs/chemicals, were assessed by the ROS assay according to the standardized protocol. Most phototoxins tended to generate singlet oxygen and/or superoxide under UV-vis exposure, but nonphototoxic chemicals were less photoreactive. In the ROS assay on quinine (200 µm), a typical phototoxic drug, the intra- and inter-day precisions (coefficient of variation; CV) were found to be 1.5-7.4% and 1.7-9.3%, respectively. The inter-laboratory CV for quinine averaged 15.4% for singlet oxygen and 17.0% for superoxide. The ROS assay on 42 coded chemicals (200 µm) provided no false negative predictions upon previously defined criteria as compared with the in vitro/in vivo phototoxicity, although several false positives appeared. Outcomes from the validation study were indicative of satisfactory transferability, intra- and inter-laboratory variability, and predictive capacity of the ROS assay.
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Affiliation(s)
- Satomi Onoue
- Department of Pharmacokinetics and Pharmacodynamics, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka, 422-8526, Japan
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26
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Abstract
DNA damage induced by photosensitization is not only responsible for the genotoxic effects of various types of drugs in the presence of light, but is also relevant for some of the adverse effects of sunlight, in particular in the UVA and visible range of the spectrum. The types of DNA modifications induced are very diverse and include pyrimidine dimers, covalent adducts, various base modifications generated by oxidation, single-strand breaks and (regular and oxidized) sites of base loss. The ratios in which the various modifications are formed (damage spectra) can be regarded as a fingerprint of the damaging mechanism. Here, we describe the damage spectra of various classes of photosensitizers in relation to the underlying damaging mechanisms. In mammalian cells irradiated with solar radiation, damage at wavelengths <400 nm is characteristic for a (not yet identified) endogenous type-I or type-II photosensitizer. In the UVA range, however, both direct DNA excitation and photosensitized damage appear to be relevant, and there are indications that other chromophore(s) are involved than in the visible range.
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Affiliation(s)
- Bernd Epe
- Institute of Pharmacy and Biochemistry, University of Mainz, Staudingerweg 5, D-55099, Mainz, Germany.
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27
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de Guidi G, Bracchitta G, Catalfo A. Photosensitization Reactions of Fluoroquinolones and Their Biological Consequences. Photochem Photobiol 2011; 87:1214-29. [DOI: 10.1111/j.1751-1097.2011.00978.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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28
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Lynch AM, Guzzie PJ, Bauer D, Gocke E, Itoh S, Jacobs A, Krul CA, Schepky A, Tanaka N, Kasper P. Considerations on photochemical genotoxicity. II: Report of the 2009 International Workshop on Genotoxicity Testing Working Group. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2011; 723:91-100. [DOI: 10.1016/j.mrgentox.2010.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Accepted: 10/07/2010] [Indexed: 02/05/2023]
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29
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Horinouchi M, Arimoto-Kobayashi S. Photomicronucleus assay of phototoxic and pseudophotoclastogenic chemicals in human keratinocyte NCTC2544 cells. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2011; 723:43-50. [DOI: 10.1016/j.mrgentox.2011.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 03/15/2011] [Accepted: 04/10/2011] [Indexed: 12/31/2022]
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30
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Takamura-Enya T, Ishii R, Oda Y. Evaluation of photo-genotoxicity using the umu test in strains with a high sensitivity to oxidative DNA damage. Mutagenesis 2011; 26:499-505. [DOI: 10.1093/mutage/ger008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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31
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Toyooka T, Ishihama M, Ibuki Y. Phosphorylation of histone H2AX is a powerful tool for detecting chemical photogenotoxicity. J Invest Dermatol 2011; 131:1313-21. [PMID: 21368771 DOI: 10.1038/jid.2011.28] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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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32
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An evaluation of chemical photoreactivity and the relationship to photogenotoxicity. Regul Toxicol Pharmacol 2010; 58:219-23. [DOI: 10.1016/j.yrtph.2009.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Revised: 10/27/2009] [Accepted: 11/08/2009] [Indexed: 11/13/2022]
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33
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Reus AA, van Meeuwen RNC, de Vogel N, Maas WJM, Krul CAM. Development and characterisation of an in vitro photomicronucleus test using ex vivo human skin tissue. Mutagenesis 2010; 26:261-8. [DOI: 10.1093/mutage/geq056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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34
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Development and characterization of an in vivo skin photomicronucleus assay in rats. Mutagenesis 2010; 25:407-16. [DOI: 10.1093/mutage/geq023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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35
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High-Throughput Screening System for Identifying Phototoxic Potential of Drug Candidates Based on Derivatives of Reactive Oxygen Metabolites. Pharm Res 2010; 27:1610-9. [DOI: 10.1007/s11095-010-0161-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Accepted: 04/15/2010] [Indexed: 10/19/2022]
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36
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Seto Y, Ochi M, Onoue S, Yamada S. High-throughput screening strategy for photogenotoxic potential of pharmaceutical substances using fluorescent intercalating dye. J Pharm Biomed Anal 2010; 52:781-6. [PMID: 20236783 DOI: 10.1016/j.jpba.2010.02.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2009] [Revised: 02/17/2010] [Accepted: 02/19/2010] [Indexed: 10/19/2022]
Abstract
The aim of the present study was to provide an intercalator-based photogenotoxicity (IBP) assay as a high-throughput in vitro screening system for predicting the photogenotoxic potential of pharmaceutical substances. The conditions of the high-throughput IBP assay using thiazole orange (TO), a fluorescent intercalating dye, were optimized and validated by a fluorescence titration experiment and reproducibility/robustness test. The IBP assay was applied to 27 phototoxic and 5 weak/non-phototoxic commercially available compounds, and other phototoxicity screenings were also carried out for comparison; these included the reactive oxygen species (ROS) assay for overall phototoxic potential and the DNA-photocleavage assay for photogenotoxic risk. According to the results from the comparative experiments, a decreased level of intercalated TO in the IBP assay could theoretically be related to the DNA-photocleaving behaviors of phototoxic drugs, but not to their ROS-generating abilities. The IBP assay could predict the photodynamic DNA impairment caused by irradiated drugs with a prediction accuracy of 78%. These findings suggest that the IBP assay could be a fast and reliable tool for predicting the photogenotoxic potential of a large number of drug candidates at early stages of drug discovery.
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Affiliation(s)
- Yoshiki Seto
- Department of Pharmacokinetics and Pharmacodynamics and Global Center of Excellence Program, School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan
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37
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Onoue S, Seto Y, Oishi A, Yamada S. Novel Methodology for Predicting Photogenotoxic Risk of Pharmaceutical Substances Based on Reactive Oxygen Species (ROS) and DNA-Binding Assay. J Pharm Sci 2009; 98:3647-58. [DOI: 10.1002/jps.21670] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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38
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Hartmann A, Speit G. Comet Assay – Protocols and Testing Strategies. THE COMET ASSAY IN TOXICOLOGY 2009. [DOI: 10.1039/9781847559746-00373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Andreas Hartmann
- Novartis Pharma AG Preclinical Safety WKL105.4. 09 CH-4002 Basel Switzerland
| | - Günter Speit
- Universität Ulm Institut für Humangenetik D-89069 Ulm Germany
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39
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Attia SM. Use of centromeric and telomeric DNA probes in in situ hybridization for differentiation of micronuclei induced by lomefloxacin. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2009; 50:394-403. [PMID: 19230000 DOI: 10.1002/em.20451] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Classification of micronuclei induced by lomefloxacin, a difluorinated quinolone bactericidal agent, in mouse bone marrow was performed by fluorescence in situ hybridization using DNA probes for the centromere repeated minor satellite DNA and the telomeric hexamer repeat (5'-TTAGGG-3'). Colchicine and mitomycin C were used as a positive control aneugen and clastogen, respectively, and these compounds produced the expected responses. Single doses of 40, 80, 160, or 320 mg/kg lomefloxacin were given via oral intubations and bone marrow was sampled at 24 and 48 hr after treatment. The micronuclei showed significant increases in both sampling times after doses of 320 mg/kg. A statistically significant increase of micronuclei frequency was also detected for 160 mg/kg lomefloxacin at 48 hr after treatment. The responses were directly correlated with bone-marrow cytotoxicity. Following treatment with 160 and 320 mg/kg lomefloxacin, 48.2 and 50.0% of the induced micronuclei, respectively, showed double labeling with centromeric signals and several telomeric signals, indicating that the induced micronuclei were composed of whole chromosomes. Similarly, 51.8 and 50.0% of the induced micronuclei, respectively, were centromere-negative, demonstrating that lomefloxacin not only induces chromosome loss but also chromosome breakage. The results also showed that chromosomes can be enclosed in a micronucleus before and after centromere separation. Overall, this study provides the first evidence of the potential of lomefloxacin to induce aneugenic effect in mice. However, given the high doses used in this study, the clinical significance of this finding is uncertain.
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Affiliation(s)
- Sabry M Attia
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt.
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40
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Reply to the Letter to the Editor. MUTATION RESEARCH/GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2009. [DOI: 10.1016/j.mrgentox.2009.05.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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41
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Mei N, Chen T, Godar DE, Moore MM. UVA-induced photomutagenicity of retinyl palmitate. Mutat Res 2009; 677:105-6; author reply 107-8. [PMID: 19477293 DOI: 10.1016/j.mrgentox.2009.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Accepted: 05/15/2009] [Indexed: 10/20/2022]
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42
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Verdel B, Souverein P, Meyboom R, Kardaun S, Leufkens H, Egberts A. Risk of drug-induced photosensitivity: focus on spectroscopic and molecular characteristics. Pharmacoepidemiol Drug Saf 2009; 18:602-9. [DOI: 10.1002/pds.1760] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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43
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Dufour EK, Whitwell J, Nohynek GJ, Kirkland D, Toutain H. Retinyl palmitate is non-genotoxic in Chinese hamster ovary cells in the dark or after pre-irradiation or simultaneous irradiation with UV light. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2009; 672:21-6. [DOI: 10.1016/j.mrgentox.2008.09.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 08/29/2008] [Accepted: 09/21/2008] [Indexed: 11/16/2022]
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44
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Tripathi DN, Pawar AA, Vikram A, Ramarao P, Jena GB. Use of the alkaline comet assay for the detection of transplacental genotoxins in newborn mice. Mutat Res 2008; 653:134-9. [PMID: 18468946 DOI: 10.1016/j.mrgentox.2008.03.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2007] [Revised: 02/28/2008] [Accepted: 03/12/2008] [Indexed: 11/30/2022]
Abstract
Several lines of evidence show that in utero exposure to different toxicants has greater consequences than their exposure during adult life. This may be due to involvement of critical developmental stages, physiological immaturity and the long later-life span over which disease may initiate, develop and progress. The in vivo alkaline comet (single-cell gel electrophoresis) assay has been favoured by the scientific community for the evaluation of genotoxins. The objective of this study was to demonstrate the suitability of alkaline comet assay in detecting transplacental genotoxins using newborn mice. Here, we report the successful use of the comet assay in detecting multi-organ genotoxicity of known transplacental genotoxins in newborn mice. Three well known transplacental genotoxic agents, cyclophosphamide (CP), mitomycin-C (MMC) and zidovudine (AZT) were tested in pregnant Swiss mice. These compounds were administered in the late gestational period (16-20th days of pregnancy) and the comet assay was performed with lymphocytes, bone marrow, liver and kidney cells of newborn mice. Significant DNA damage was observed in all the tissues with tested transplacental genotoxins. The results of the comet assay were confirmed by the micronucleus (MN) assay of the peripheral blood of newborn mice. The results of this study provide sufficient evidence that the comet assay can be applied successfully for the detection of transplacental genotoxins in newborn mice.
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Affiliation(s)
- D N Tripathi
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research, Sector-67, S.A.S. Nagar, Mohali, Punjab 160062, India
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Struwe M, Greulich KO, Junker U, Jean C, Zimmer D, Suter W, Plappert-Helbig U. Detection of photogenotoxicity in skin and eye in rat with the photo comet assay. Photochem Photobiol Sci 2008; 7:240-9. [DOI: 10.1039/b715756h] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Verma K, Agrawal N, Misra RB, Farooq M, Hans RK. Phototoxicity assessment of drugs and cosmetic products using E. coli. Toxicol In Vitro 2007; 22:249-53. [PMID: 17919881 DOI: 10.1016/j.tiv.2007.08.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Revised: 06/28/2007] [Accepted: 08/20/2007] [Indexed: 11/18/2022]
Abstract
A gram negative bacteria Escherichia coli (Dh5alpha strain) was developed as an alternate test system of phototoxicity. Eight drugs (antibiotics) and cosmetic products (eight face creams) were examined for their phototoxicity using this test system. Five known phototoxic compounds were used to validate the test system. UVA-radiation induced phototoxicity of these compounds was tested by agar gel diffusion assay. Decrease in colony forming units (CFU) was taken as an end point of phototoxicity. The phototoxic compounds and antibiotics produced significant reduction in CFU (p<0.001) at 80 microg/ml concentrations under exposure to UVA-radiation (5.4-10.8 J/cm(2)). One face cream was found phototoxic and produced significant decrease in CFU of E. coli at 1.0mg/ml concentration under UVA exposure (10.8 J/cm(2)). The minimum effective concentration of tetracycline and dose of UVA-radiation were also determined by observing growth inhibition of E. coli through disc diffusion assay. The observations suggested that E. coli can be used as an alternative test system for phototoxicity evaluation of chemicals. A battery of test systems is required to conclude the toxic/phototoxic potential of a chemical agent. In view of the speed, easiness, sensitivity and low cost, E. coli is introduced as one of the alternate test system for phototoxicity studies in safety evaluation of various chemical ingredients or formulations used in cosmetics and drugs.
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Affiliation(s)
- K Verma
- Photobiology Division, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Post Box No. 80, Lucknow 226001, UP, India
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Struwe M, Greulich KO, Suter W, Plappert-Helbig U. The photo comet assay—A fast screening assay for the determination of photogenotoxicity in vitro. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2007; 632:44-57. [PMID: 17572134 DOI: 10.1016/j.mrgentox.2007.04.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 03/02/2007] [Accepted: 04/11/2007] [Indexed: 11/16/2022]
Abstract
Different classes of chemicals can induce a phototoxic effect by absorbing light energy within the wavelength range of sunlight. The assessment of photo-safety is therefore an obligatory part of the development of new drugs. Ten UV-vis (280-800nm)-absorbing compounds (ketoprofen, promazine, chlorpromazine, dacarbazine, acridine, lomefloxacin, 8-methoxypsoralen, chlorhexidine, titanium dioxide, octylmethoxycinnamate) were tested for their photogenotoxic potential in the alkaline comet assay in the presence and absence of UV-vis. In order to establish an easy and timesaving protocol for a photo comet assay screening test, the application of 96-well plates was essential. The use of mouse lymphoma L5178Y cells, a cell line growing in suspension, allowed the determination of photocytotoxicity with the Alamar Blue assay and of photogenotoxicity with the alkaline comet assay in parallel. L5178Y cells were incubated with the test compounds for 20min and irradiated with simulated sunlight in the wavelength range from 280 to 800nm. The applied UV dose was 600mJ/cm(2) UV-A and 30mJ/cm(2) UV-B. After a post-incubation of 10min, the Alamar Blue assay and the alkaline comet assay were performed. All of the compounds which are known to be photogenotoxic (8-methoxypsoralen, acridine, chlorpromazine, dacarbazine, ketoprofen, lomefloxacin) showed a positive effect under our assay conditions. Furthermore, four UV-vis absorbing chemicals which are known to be not photogenotoxic (promazine, chlorhexidine, titanium dioxide, octylmethoxycinnamate) were analysed. For none of them an increase of the DNA damage following irradiation was observed in this study. In conclusion, all of the chemical compounds tested were classified in agreement with published data. From the data presented it is concluded that the photo comet assay with L5178Y mouse lymphoma cells is a reliable model to assess photochemical genotoxicity in vitro.
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Affiliation(s)
- Melanie Struwe
- Genetic Toxicology and Safety Pharmacology, Exploratory Development, Novartis Pharma AG, Basel, Switzerland.
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Hara T, Nishikawa T, Sui H, Kawakami K, Matsumoto H, Tanaka N. In vivo photochemical skin micronucleus test using a sunlight simulator: Detection of 8-methoxypsoralen and benzo[a]pyrene in hairless mice. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2007; 631:1-8. [PMID: 17512241 DOI: 10.1016/j.mrgentox.2007.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2006] [Revised: 03/12/2007] [Accepted: 03/14/2007] [Indexed: 11/25/2022]
Abstract
Evaluating in vivo photochemical genotoxicity (photogenotoxicity) or photochemical carcinogenicity (photocarcinogenicity) in the skin that is actually exposed to light is important for estimating the risk of human exposure to chemicals under sunlight. With regard to the skin micronucleus test, Nishikawa et al. developed a reliable technique that is simple and in which the negative control has a stable background. In the present study, we applied 8-methoxypsoralen (8-MOP) and benzo[a]pyrene (B[a]P) to the backs of hairless mice and subjected the mice to irradiation by a sunlight simulator in order to investigate whether this test can detect photogenotoxicity of these chemicals. In the treatment with 8-MOP [0.00075% and 0.0015% (w/v)], a significant increase was observed in the frequency of micronucleated cells only under light irradiation using the sunlight simulator. At a high chemical dose, the frequency of micronucleated cells increased from 48h after the treatment, peaked at 96h, and then decreased at 168h. Furthermore, at 96h with the high dose under light irradiation, we frequently observed cells with nuclear buds. In the treatment with B[a]P [first experiment: 0.025% and 0.05% (w/v); second experiment: 0.005%, 0.01%, and 0.02% (w/v)], a significant increase was observed in the frequency of micronucleated cells at skin-irritating doses [0.01%, 0.02%, 0.025%, and 0.05% (w/v)] at 72 or 96h after the treatment only under light irradiation using the sunlight simulator. In conclusion, photogenotoxicity of 8-MOP and B[a]P was detected in the in vivo photochemical skin micronucleus study.
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Affiliation(s)
- Takumi Hara
- Division of Genetic Toxicology, Hatano Research Institute, Food and Drug Safety Center, 729-5 Ochiai, Hadano, Kanagawa 257-8523, Japan
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Onoue S, Tsuda Y. Analytical Studies on the Prediction of Photosensitive/Phototoxic Potential of Pharmaceutical Substances. Pharm Res 2006; 23:156-64. [PMID: 16308671 DOI: 10.1007/s11095-005-8497-9] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2005] [Accepted: 09/14/2005] [Indexed: 11/25/2022]
Abstract
PURPOSE Phototoxic responses after administration of photosensitive pharmaceutics have been recognized as undesirable side effects, and predicting potential hazardous side effects is gaining importance as new drugs are introduced to the market. In this work, we characterize the photochemical/photobiological properties of model compounds to develop an effective screening method for the prediction of phototoxic/photosensitive potential. METHODS Twenty-one known photosensitive/phototoxic compounds and five weak/nonphototoxic compounds were subjected to ultraviolet (UV) spectral analyses and photochemical evaluation including the determination of produced reactive oxygen species (ROS) and photostability study. The photooxidation of linoleic acid was also monitored in the presence of tested compounds, guided on the formation of thiobarbituric acid reactive substances. RESULTS Most photosensitive/phototoxic drugs tested, even weak UV absorbers, at a concentration of 200 microM showed significant production of ROS under 18 h light exposure (30,000 lx). On the other hand, ROS generated from weak/nonphototoxic compounds, including strong UV absorber benzocaine, were low or negligible. Although exposure of quinine to light resulted in significant degradation (half-life, t1/2=6.4 h), it was dramatically attenuated by the addition of ROS scavengers, especially sodium azide (t1/2=122.6 h). Furthermore, concomitant exposure of photosensitive/phototoxic compounds (200 microM) and linoleic acid (1 mM) for 18 h led to the marked formation of lipoperoxide. CONCLUSION Results indicated that known photosensitive/phototoxic compounds tested have the ability to generate ROS under light exposure, and this photochemical reaction could be associated with their photoinstability and/or phototoxic responses. Based on these findings, determination of ROS, generated from photoirradiated compounds, may be an effective predictive model in recognizing their photosensitive/phototoxic potential.
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Affiliation(s)
- Satomi Onoue
- Analytical Research and Development, Pfizer Global Research and Development, Nagoya Laboratories, Pfizer Japan Inc., 5-2 Taketoyo, Aichi, 470-2393, Japan.
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Wirnitzer U, Gross-Tholl N, Herbold B, von Keutz E. Photo-chemically induced DNA effects in the comet assay with epidermal cells of SKH-1 mice after a single oral administration of different fluoroquinolones and 8-methoxypsoralen in combination with exposure to UVA. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2006; 609:1-10. [PMID: 16824784 DOI: 10.1016/j.mrgentox.2006.05.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2006] [Revised: 05/09/2006] [Accepted: 05/13/2006] [Indexed: 11/16/2022]
Abstract
UNLABELLED Due to the need for in vivo photo-genotoxicity tests, the in vivo photo-comet assay was established in epidermal cells of the SKH-1 mouse. Groups of 10 male SKH-1 mice each were treated once orally with vehicle only, with three fluoroquinolones (25 mg/kg clinafloxacin, 20 mg/kg lomefloxacin, 200 mg/kg ciprofloxacin) or with 200mg/kg 8-methoxypsoralene (8-MOP). Thirty minutes after treatment half of the mice in each group were exposed to 23.8 J/cm2 UVA. Thereafter the mice were killed and their epidermal cells tested in the alkaline (pH >13) comet assay; at the same time after administration, compound-treated, non-irradiated mice were killed and analysed. A negative control group of ten male SKH-1 mice received the vehicle only; half of these animals were exposed to UVA, half were not. The comet tail lengths of epidermal cells of the mice were statistically significantly increased for all three fluoroquinolones (FQ) tested in combination with UV irradiation. Treatment with 8-methoxypsoralene+UV induced a significant reduction of comet tail length. Tail intensity and tail moment gave essentially the same results after combined exposure (compound+UV). Without irradiation, the tail lengths of controls and compound-treated mice were comparable under the conditions of this study. In contrast, tail intensity and tail moment were increased for all test compounds (including 8-MOP), without irradiation. Irradiated controls had a tail length comparable to non-irradiated controls, while tail intensity and tail moment were clearly increased in irradiated controls. IN CONCLUSION under the present experimental conditions the in vivo photo-comet assay is able to detect photo-chemically induced DNA strand breaks as well as photo-chemically induced DNA cross-links.
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Affiliation(s)
- Uta Wirnitzer
- Bayer HealthCare AG, Pharma Center, Toxicology, Building 514, P.O. Box 101709, 42096 Wuppertal, Germany.
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