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Port-Lougarre Y, Gourlaouen C, Vileno B, Giménez-Arnau E. Antioxidant Activity and Skin Sensitization of Eugenol and Isoeugenol: Two Sides of the Same Coin? Chem Res Toxicol 2023; 36:1804-1813. [PMID: 37922503 DOI: 10.1021/acs.chemrestox.3c00263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2023]
Abstract
Eugenol and isoeugenol are well acknowledged to possess antioxidant and thus cytoprotective activities. Yet both compounds are also important skin sensitizers, compelling the cosmetics and fragrance industries to notify their presence in manufactured products. While they are structurally very similar, they show significant differences in their sensitization properties. Consequently, eugenol and isoeugenol have been the subject of many mechanistic studies where the final oxidation forms, electrophilic ortho-quinone and quinone methide, are blamed as the reactive species forming an antigenic complex with nucleophilic residues of skin proteins, inducing skin sensitization. However, radical mechanisms could compete with such an electrophilic-nucleophilic pathway. The antioxidant activity results from neutralizing reactive oxygen radicals by the release of the phenolic hydrogen atom. The so-formed phenoxyl radicals can then fully delocalize upon the structure, becoming potentially reactive toward skin proteins at several positions. To obtain in-depth insights into such reactivity, we investigated in situ the formation of radicals from eugenol and isoeugenol using electron paramagnetic resonance combined with spin trapping in reconstructed human epidermis (RHE), mimicking human skin and closer to what may happen in vivo. Two modes of radical initiation were used, exposing RHE to (i) horseradish peroxidase (HRP), complementing RHE metabolic capacities, and mimicking peroxidases present in vivo or (ii) solar light using a AM 1.5 solar simulator. In both experimental approaches, where the antioxidant character of both compounds is revealed, oxygen- and carbon-centered radicals were formed in RHE. Our hypothesis is that such carbon radicals are relevant candidates to form antigenic entities prior to conversion into electrophilic quinones. On this basis, these studies suggest that pro- or prehapten fingerprints could be advanced depending on the radical initiation method. The introduction of HRP suggested that eugenol and isoeugenol behave as prohaptens, while when exposed to light, a prehapten nature could be highlighted.
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Affiliation(s)
- Yannick Port-Lougarre
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Christophe Gourlaouen
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Bertrand Vileno
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
| | - Elena Giménez-Arnau
- Institut de Chimie, UMR 7177, CNRS, Université de Strasbourg, 4 Rue Blaise Pascal, 67000 Strasbourg, France
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Mittag JJ, Trutschel ML, Kruschwitz H, Mäder K, Buske J, Garidel P. Characterization of radicals in polysorbate 80 using electron paramagnetic resonance (EPR) spectroscopy and spin trapping. Int J Pharm X 2022; 4:100123. [PMID: 35795322 PMCID: PMC9251573 DOI: 10.1016/j.ijpx.2022.100123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 06/21/2022] [Indexed: 11/21/2022] Open
Abstract
Polysorbates are an important class of nonionic surfactants that are widely used to stabilize biopharmaceuticals. The degradation of polysorbate 20 and 80 and the related particle formation in biologics are heavily discussed in the pharmaceutical community. Although a lot of experimental effort was spent in the detailed study of potential degradation pathways, the underlying mechanisms are only sparsely understood. Besides enzymatic hydrolysis, another proposed mechanism is associated with radical-induced (auto)oxidation of polysorbates. To characterize the types and the origin of the involved radicals and their propagation in bulk material as well as in diluted polysorbate 80 solutions, we applied electron paramagnetic resonance (EPR) spectroscopy using a spin trapping approach. The prerequisite for a meaningful experiment using spin traps is an understanding of the trapping rate, which is an interplay of (i) the presence of the spin trap at the scene of action, (ii) the specific reactivity of the selected spin trap with a certain radical as well as (iii) the stability of the formed spin adducts (a slow decay rate). We discuss whether and to which extent these criteria are fulfilled regarding the identification of different radical classes that might be involved in polysorbate oxidative degradation processes. The ratio of different radicals for different scenarios was determined for various polysorbate 80 quality grades in bulk material and in aqueous solution, showing differences in the ratio of present radicals. Possible correlations between the radical content and product parameters such as the quality grade, the manufacturing date, the manufacturer, the initial peroxide content according to the certificate of analysis of polysorbate 80 are discussed.
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Key Words
- 5,5-dimethyl-1-pyrroline-N-oxide, DMPO
- DMPO
- EPR
- Oxidation
- Peroxide
- Polysorbate
- Radical
- Spin trap
- alkoxyl radical, RO•
- alkyl radical, R•
- all-oleate, AO
- certificate of analysis, CoA
- china grade, CG
- electron paramagnetic resonance, EPR
- fatty acid, FA
- high purity, HP
- hydrogen peroxide, H2O2
- hydroperoxide, ROOH
- hydroxyl radical, HO•
- peroxyl radical, ROO•
- polyoxyethylene, POE
- polysorbate, PS
- reactive oxygen species, ROS
- super-refined, SR
- superoxide, O2•−
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Affiliation(s)
- Judith J. Mittag
- Boehringer Ingelheim Pharma GmbH & Co. KG, Innovation Unit, PDB-TIP, Birkendorfer Straße 65, 88397 Biberach an der Riss, Germany
| | - Marie-Luise Trutschel
- Martin-Luther-University Halle-Wittenberg, Institute of Pharmacy, Faculty of Biosciences, Wolfgang-Langenbeck-Strasse 4, 06120 Halle (Saale), Germany
| | - Helen Kruschwitz
- Martin-Luther-University Halle-Wittenberg, Institute of Pharmacy, Faculty of Biosciences, Wolfgang-Langenbeck-Strasse 4, 06120 Halle (Saale), Germany
| | - Karsten Mäder
- Martin-Luther-University Halle-Wittenberg, Institute of Pharmacy, Faculty of Biosciences, Wolfgang-Langenbeck-Strasse 4, 06120 Halle (Saale), Germany
| | - Julia Buske
- Boehringer Ingelheim Pharma GmbH & Co. KG, Innovation Unit, PDB-TIP, Birkendorfer Straße 65, 88397 Biberach an der Riss, Germany
| | - Patrick Garidel
- Boehringer Ingelheim Pharma GmbH & Co. KG, Innovation Unit, PDB-TIP, Birkendorfer Straße 65, 88397 Biberach an der Riss, Germany
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Zhang X, Wang T, Cui S, Li L, Zheng Z, Mi C, Lin B, Ren X, He X. Design of Photosensitive Cobalt Complex Intermediates and Their Application in the Green Syntheses of Molecules Containing the Quinazolin-4(3 H)-imine Scaffold. J Org Chem 2022; 87:8303-8315. [PMID: 35709489 DOI: 10.1021/acs.joc.1c02987] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cobalt/photoredox cooperative catalysis is a well-explored technology for visible-light photoredox catalysis. Recently, the photosensitivity of Co(II) complexes in homogeneous catalysis has aroused the interest of scientists. In this study, photosensitive Co(II) complex intermediates were designed to develop new synthetic methods. These intermediates, consisting of Co(II) and two substrate molecules, bind to O2 and absorb visible light over a wide spectral range, triggering in situ oxidative decarboxylation to produce molecules containing the quinazolin-4(3H)-imine scaffold. These reactions employed glyoxylic acid and ketoacids as new building blocks, and good to excellent yields of the corresponding products were obtained under mild reaction conditions using green and inexpensive reagents and solvents. These results are of importance since the design of Co-based photosensitive intermediates will aid in establishing novel methods for harnessing visible light and hence lead to innovation in organic syntheses.
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Affiliation(s)
- Xianwei Zhang
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, 27 Taiping Road, Haidian District, Beijing 100850, China
| | - Tianzhao Wang
- Key Laboratory of Structure-Based Drug Design and Discovery, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Shisheng Cui
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, 27 Taiping Road, Haidian District, Beijing 100850, China
| | - Lei Li
- Key Laboratory of Structure-Based Drug Design and Discovery, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Zhibing Zheng
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, 27 Taiping Road, Haidian District, Beijing 100850, China
| | - Chunlai Mi
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, 27 Taiping Road, Haidian District, Beijing 100850, China
| | - Bin Lin
- Key Laboratory of Structure-Based Drug Design and Discovery, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Xuhong Ren
- Key Laboratory of Structure-Based Drug Design and Discovery, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenhe District, Shenyang 110016, China
| | - Xinhua He
- State Key Laboratory of Toxicology and Medical Countermeasures, Institute of Pharmacology and Toxicology, 27 Taiping Road, Haidian District, Beijing 100850, China
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Spin Trapping Hydroxyl and Aryl Radicals of One-Electron Reduced Anticancer Benzotriazine 1,4-Dioxides. Molecules 2022; 27:molecules27030812. [PMID: 35164077 PMCID: PMC8840461 DOI: 10.3390/molecules27030812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/19/2022] [Accepted: 01/21/2022] [Indexed: 02/06/2023] Open
Abstract
Hypoxia in tumors results in resistance to both chemotherapy and radiotherapy treatments but affords an environment in which hypoxia-activated prodrugs (HAP) are activated upon bioreduction to release targeted cytotoxins. The benzotriazine 1,4-di-N-oxide (BTO) HAP, tirapazamine (TPZ, 1), has undergone extensive clinical evaluation in combination with radiotherapy to assist in the killing of hypoxic tumor cells. Although compound 1 did not gain approval for clinical use, it has spurred on the development of other BTOs, such as the 3-alkyl analogue, SN30000, 2. There is general agreement that the cytotoxin(s) from BTOs arise from the one-electron reduced form of the compounds. Identifying the cytotoxic radicals, and whether they play a role in the selective killing of hypoxic tumor cells, is important for continued development of the BTO class of anticancer prodrugs. In this study, nitrone spin-traps, combined with electron spin resonance, give evidence for the formation of aryl radicals from compounds 1, 2 and 3-phenyl analogues, compounds 3 and 4, which form carbon C-centered radicals. In addition, high concentrations of DEPMPO (5-(diethoxyphosphoryl)-5-methyl-1-pyrroline N-oxide) spin-trap the •OH radical. The combination of spin-traps with high concentrations of DMSO and methanol also give evidence for the involvement of strongly oxidizing radicals. The failure to spin-trap methyl radicals with PBN (N-tert-butylphenylnitrone) on the bioreduction of compound 2, in the presence of DMSO, implies that free •OH radicals are not released from the protonated radical anions of compound 2. The spin-trapping of •OH radicals by high concentrations of DEPMPO, and the radical species arising from DMSO and methanol give both direct and indirect evidence for the scavenging of •OH radicals that are involved in an intramolecular process. Hypoxia-selective cytotoxicity is not related to the formation of aryl radicals from the BTO compounds as they are associated with high aerobic cytotoxicity.
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Vileno B, Port-Lougarre Y, Giménez-Arnau E. Electron paramagnetic resonance and spin trapping to detect free radicals from allergenic hydroperoxides in contact with the skin: from the molecule to the tissue. Contact Dermatitis 2022; 86:241-253. [PMID: 34982482 DOI: 10.1111/cod.14037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 11/22/2021] [Accepted: 12/13/2021] [Indexed: 11/29/2022]
Abstract
A major research topic consists of revealing the contribution of radical-mediated reactions in dermatological diseases related to xenobiotic-induced stress, to succeed risk assessment procedures protecting producers and consumers. Allergic contact dermatitis is the clinically relevant consequence of skin sensitization, one of the most critical occupational and environmental health issues related to xenobiotics exposure. The first key event identified for the skin sensitization process to a chemical is its aptitude to react with epidermal proteins and form antigenic structures that will further trigger the immune response. Many chemical sensitizers are suspected to react through mechanisms involving radical intermediates. This review focuses on recent progress we have accomplished over the last few years studying radical intermediates derived from skin sensitizing chemicals by electron paramagnetic resonance in combination with the spin trapping technique. Our work is carried out "from the molecule", performing studies in solution, "to the tissue", by the development of a methodology on a reconstructed human epidermis model, very close in terms of histology and metabolic/enzymatic activity to real human epidermis, that can be used as suitable biological tissue model. The benefits are to test chemicals under conditions close to human use and real-life sensitization exposures and benefit from the 3D microenvironment. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Bertrand Vileno
- POMAM Laboratory, CNRS, Institute of Chemistry UMR 7177, University of Strasbourg, Strasbourg, France
| | - Yannick Port-Lougarre
- Dermatochemistry Laboratory, CNRS, Institute of Chemistry UMR 7177, University of Strasbourg, Strasbourg, France
| | - Elena Giménez-Arnau
- Dermatochemistry Laboratory, CNRS, Institute of Chemistry UMR 7177, University of Strasbourg, Strasbourg, France
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Grachev DI, Shumaev KB, Kosmachevskaya OV, Topunov AF, Ruuge EK. Nitrosyl Comlexes of Hemoglobin in Various Model Systems. Biophysics (Nagoya-shi) 2021. [DOI: 10.1134/s000635092106004x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Tokhy HH, Elmaghraby EK, Abdelhady AM, Eid AM, Rammah YS, Awad ESM, Abdelaal S. The influence of gamma radiation on organic compounds having carbon ring and its application in dosimetry. RADIOCHIM ACTA 2021. [DOI: 10.1515/ract-2020-0024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The formation of highly oxidizing radicals in multifunctional-solid compounds upon irradiation with gamma-ray had been investigated. Five organic compounds having a single carbon ring had been used in the present investigation; these materials are 1-chloro-4-nitrobenzene, 4′-aminoacetophenone, 3′-hydroxyacetophenone, n-anthranilic acid, and triphenylmethane. These material were irradiated using 60Co radiation with different doses between 20 and 100 kGy. Electron spin resonance spectroscopy spotted increases of the resonance absorption having landé factor around 2.0113 ± 0.003 upon irradiation with the increasing of dose. This resonance absorption was related to the formation of long-lived oxygen radicals that were attached to one of the radiation synthesized compounds. The method of infrared absorption spectroscopy emphasized the formation of cyclic and aliphatic hexane in addition to the active oxygen radicals. n-Anthranilic acid was found to be suitable for radiation the dosimetry with long-lasting radiation signature as electron spin and also to determine the exposure dose. The time-lapse infrared and electron spin resonance measurements had been used to tracked the formation of active species within the time-lapsed after the end of exposure; results showed that the dosimetric signature may be used as a tracker for the time when the exposure happens.
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Affiliation(s)
- Hatem Hussny Tokhy
- Department of Radiation Protection and Dosimetry , National Center for Radiation Research and Technology NCRRT, Atomic Energy Authority , Cairo 13759 , Egypt
- Physics Department , Faculty of Science, Menoufia University , Shebin El-Koom 32511 , Egypt
| | - Elsayed K. Elmaghraby
- Experimental Nuclear Physics Department , Nuclear Research Centre, Egyptian Atomic Energy Authority , Cairo 13759 , Egypt
| | - AbdelWahab M. Abdelhady
- Accelerator and Ion Sources Department , Nuclear Research Center, Egyptian Atomic Energy Authority , Cairo 13759 , Egypt
- Central Lab for Elemental and Isotopic Analysis, Nuclear Research Center, Egyptian Atomic Energy Authority , Cairo 13759 , Egypt
| | - Ahmed M. Eid
- Department of Radiation Protection and Dosimetry , National Center for Radiation Research and Technology NCRRT, Atomic Energy Authority , Cairo 13759 , Egypt
| | - Yasser S. Rammah
- Physics Department , Faculty of Science, Menoufia University , Shebin El-Koom 32511 , Egypt
| | - El-Sayed M. Awad
- Physics Department , Faculty of Science, Menoufia University , Shebin El-Koom 32511 , Egypt
| | - Saad Abdelaal
- Accelerator and Ion Sources Department , Nuclear Research Center, Egyptian Atomic Energy Authority , Cairo 13759 , Egypt
- Central Lab for Elemental and Isotopic Analysis, Nuclear Research Center, Egyptian Atomic Energy Authority , Cairo 13759 , Egypt
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8
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Kuresepi S, Vileno B, Lepoittevin JP, Giménez-Arnau E. Mechanistic Insights on Skin Sensitization to Linalool Hydroperoxides: EPR Evidence on Radical Intermediates Formation in Reconstructed Human Epidermis and 13C NMR Reactivity Studies with Thiol Residues. Chem Res Toxicol 2020; 33:1922-1932. [PMID: 32441093 DOI: 10.1021/acs.chemrestox.0c00125] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Linalool is one of the most commonly used fragrance terpenes in consumer products. While pure linalool is considered as non-allergenic because it has a very low skin sensitization potential, its autoxidation on air leads to allylic hydroperoxides that have been shown to be major skin sensitizers. These hydroperoxides have the potential to form antigens via radical mechanisms. In order to obtain in-depth insights of such reactivity, we first investigated the formation of free radicals derived from linalool hydroperoxides in situ in a model of human reconstructed epidermis by electron paramagnetic resonance combined with spin trapping. The formation of carbon- and oxygen-centered radical species derived from the hydroperoxides was especially evidenced in an epidermis model, mimicking human skin and thus closer to what may happen in vivo. To further investigate these results, we synthesized linalool hydroperoxides containing a 13C-substitution at positions precursor of carbon radicals to elucidate if one of these positions could react with cysteine, its thiol chemical function being one of the most labile groups prone to react through radical mechanisms. Reactions were followed by mono- and bidimensional 13C NMR. We validated that carbon radicals derived from allylic hydrogen abstraction by the initially formed alkoxyl radical and/or from its β-scission can alter directly the lateral chain of cysteine forming adducts via radical processes. Such results provide an original vision on the mechanisms likely involved in the reaction with thiol groups that might be present in the skin environment. Consequently, the present findings are a step ahead toward the understanding of protein binding processes to allergenic allylic hydroperoxides of linalool through the involvement of free radical species and thus of their sensitizing potential.
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Affiliation(s)
- Salen Kuresepi
- Dermatochemistry Laboratory, University of Strasbourg, CNRS, UMR 7177, F-67000 Strasbourg, France
| | - Bertrand Vileno
- POMAM Laboratory, University of Strasbourg, CNRS, UMR 7177, F-67000 Strasbourg, France.,French EPR Federation of Research, REseau NAtional de RPE interDisciplinaire, RENARD, Fédération IR-RPE CNRS 3443, F-67000 Strasbourg, France
| | - Jean-Pierre Lepoittevin
- Dermatochemistry Laboratory, University of Strasbourg, CNRS, UMR 7177, F-67000 Strasbourg, France
| | - Elena Giménez-Arnau
- Dermatochemistry Laboratory, University of Strasbourg, CNRS, UMR 7177, F-67000 Strasbourg, France
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Barriga-González G, Aliaga C, Chamorro E, Olea-Azar C, Norambuena E, Porcal W, González M, Cerecetto H. Synthesis and evaluation of new heteroaryl nitrones with spin trap properties. RSC Adv 2020; 10:40127-40135. [PMID: 35520832 PMCID: PMC9057510 DOI: 10.1039/d0ra07720h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 10/09/2020] [Indexed: 12/03/2022] Open
Abstract
A new series of heteroaryl nitrones were synthesized and evaluated as free radical traps due to the results showed in our previous report. The physicochemical characterization of these new nitrones by electron spin resonance (ESR) demonstrated their high capability to trap and stabilize different atom centered free radicals generated by the Fenton reaction. Additionally, we intensely studied them in terms of their physicochemical properties. Kinetic studies, including the use of a method based on competition and the hydroxyl adduct decay, gave the corresponding rate constants and half-lives at the physiological pH of these newly synthesized nitrones. New nitrones derived from quinoxaline 1,4-dioxide heterocycles were more suitable than DMPO to trap hydroxyl free radicals with a half-life longer than two hours. We explain some of the results using computational chemistry through density functional theory (DFT). A new series of heteroaryl nitrones were synthesized and evaluated as free radical traps due to the results showed in our previous report.![]()
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Affiliation(s)
- G. Barriga-González
- Departamento de Química
- Facultad de Ciencias Básicas
- Universidad Metropolitana de Ciencias de la Educación
- Santiago
- Chile
| | - C. Aliaga
- Facultad de Química y Biología
- Universidad de Santiago de Chile
- Santiago
- Chile
- Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA
| | - E. Chamorro
- Departamento de Ciencias Químicas
- Facultad de Ciencias Exactas
- Universidad Andrés Bello
- 8370146 Santiago
- Chile
| | - C. Olea-Azar
- Departamento de Química Inorgánica y Analítica
- Facultad de Ciencias Químicas y Farmacéuticas
- Universidad de Chile
- Santiago
- Chile
| | - E. Norambuena
- Departamento de Química
- Facultad de Ciencias Básicas
- Universidad Metropolitana de Ciencias de la Educación
- Santiago
- Chile
| | - W. Porcal
- Grupo de Química Orgánica Medicinal
- Laboratorio de Química Orgánica
- Facultad de Ciencias/Facultad de Química
- Universidad de la República
- Montevideo
| | - M. González
- Grupo de Química Orgánica Medicinal
- Laboratorio de Química Orgánica
- Facultad de Ciencias/Facultad de Química
- Universidad de la República
- Montevideo
| | - H. Cerecetto
- Grupo de Química Orgánica Medicinal
- Laboratorio de Química Orgánica
- Facultad de Ciencias/Facultad de Química
- Universidad de la República
- Montevideo
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Shein M, Jeschke G. Comparison of Free Radical Levels in the Aerosol from Conventional Cigarettes, Electronic Cigarettes, and Heat-Not-Burn Tobacco Products. Chem Res Toxicol 2019; 32:1289-1298. [PMID: 30932480 PMCID: PMC6584902 DOI: 10.1021/acs.chemrestox.9b00085] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Indexed: 11/28/2022]
Abstract
Aerosols from electronic cigarettes and heat-not-burn tobacco products have been found to contain lower levels of almost all compounds from the list of Harmful and Potentially Harmful Constituents known to be present in tobacco products and tobacco smoke than smoke from conventional cigarettes. Free radicals, which also pose potential health risks, are not considered in this list, and their levels in the different product types have not yet been compared under standardized conditions. We compared the type and quantity of free radicals in mainstream aerosol of 3R4F research cigarettes, two types of electronic cigarettes, and a heat-not-burn tobacco product. Free radicals and NO in the gas phases were separately spin trapped and quantified by electron paramagnetic resonance (EPR) spectroscopy by using a smoking machine for aerosol generation and a flow-through cell to enhance reproducibility of the quantification. Particulate matter was separated by a Cambridge filter and extracted, and persistent radicals were quantified by EPR spectroscopy. Levels of organic radicals for electronic cigarettes and the heat-not-burn product, as measured with the PBN spin trap, did not exceed 1% of the level observed for conventional cigarettes and were close to the radical level observed in air blanks. The radicals found in the smoke of conventional cigarettes were oxygen centered, most probably alkoxy radicals, whereas a signal for carbon-centered radicals near the detection limit was observed in aerosol from the heat-not-burn product and electronic cigarettes. The NO level in aerosol produced by electronic cigarettes was below our detection limit, whereas for the heat-not-burn product, it reached about 7% of the level observed for whole smoke from 3R4F cigarettes. Persistent radicals in particulate matter could be quantified only for 3R4F cigarettes. Aerosols from vaping and heat-not-burn tobacco products have much lower free radical levels than cigarette smoke, however, the toxicological implications of this finding are as yet unknown.
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Affiliation(s)
| | - Gunnar Jeschke
- Department of Chemistry and
Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
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11
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Sahli F, Godard A, Vileno B, Lepoittevin JP, Giménez-Arnau E. Formation of methyl radicals derived from cumene hydroperoxide in reconstructed human epidermis: an EPR spin trapping confirmation by using 13C-substitution. Free Radic Res 2019; 53:737-747. [PMID: 31130017 DOI: 10.1080/10715762.2019.1624741] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Dermal exposure to cumene hydroperoxide (CumOOH) during manufacturing processes is a toxicological issue for the industry. Its genotoxicity, mutagenic action, ability to promote skin tumour, capacity to induce epidermal hyperplasia, and aptitude to induce allergic and irritant skin contact dermatitis are well known. These toxic effects appear to be mediated through the activation to free radical species such as hydroxyl, alkoxyl, and alkyl radicals characterised basically by electron paramagnetic resonance (EPR) and spin-trapping (ST) techniques. To be a skin sensitiser CumOOH needs to covalently bind to skin proteins in the epidermis to form the antigenic entity triggering the immunotoxic reaction. Cleavage of the O-O bond allows formation of unstable CumO•/CumOO• radicals rearranging to longer half-life specific carbon-centred radicals R• proposed to be at the origin of the antigen formation. Nevertheless, it is not still clear which R• is precisely formed in the epidermis and thus involved in the sensitisation process. The aim of this work was to elucidate in conditions closer to real-life sensitisation which specific R• are formed in a 3D reconstructed human epidermis (RHE) model by using 13C-substituted CumOOH at carbon positions precursors of potentially reactive radicals and EPR-ST. We demonstrated that most probably methyl radicals derived from β-scission of CumO• radicals occur in RHE through a one-electron reductive pathway suggesting that these could be involved in the antigen formation inducing skin sensitisation. We also describe a coupling between nitroxide radicals and β position 13C atoms that could be of an added value to the very few examples existing for the coupling of radicals with 13C atoms.
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Affiliation(s)
- Fatma Sahli
- a Dermatochemistry Laboratory, University of Strasbourg-CNRS UMR 7177 , Strasbourg , France
| | - Amélie Godard
- a Dermatochemistry Laboratory, University of Strasbourg-CNRS UMR 7177 , Strasbourg , France
| | - Bertrand Vileno
- b POMAM Laboratory, University of Strasbourg-CNRS UMR 7177 , Strasbourg , France.,c French EPR Federation of Research, REseau NAtional de Rpe InterDisciplinaire (RENARD) , France
| | | | - Elena Giménez-Arnau
- a Dermatochemistry Laboratory, University of Strasbourg-CNRS UMR 7177 , Strasbourg , France
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12
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Sahli F, Sousa MSE, Vileno B, Lichter J, Lepoittevin JP, Blömeke B, Giménez-Arnau E. Understanding the skin sensitization capacity of ascaridole: a combined study of chemical reactivity and activation of the innate immune system (dendritic cells) in the epidermal environment. Arch Toxicol 2019; 93:1337-1347. [DOI: 10.1007/s00204-019-02444-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 04/09/2019] [Indexed: 01/08/2023]
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13
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Barbieriková Z, Dvoranová D, Brezová V. Photoinduced transformation of glycerol in titania suspensions. (An EPR spin trapping study of radical intermediates). Catal Today 2018. [DOI: 10.1016/j.cattod.2017.12.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Liu X, Ran M, Liu G, Liu X, Xue Z, Lu X. A sensitively non-enzymatic amperometric sensor and its application in living cell superoxide anion radical detection. Talanta 2018; 186:248-255. [DOI: 10.1016/j.talanta.2018.04.067] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/10/2018] [Accepted: 04/20/2018] [Indexed: 01/14/2023]
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15
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Wu Q, Wei G, Xu Z, Han J, Xi J, Fan L, Gao L. Mechanistic Insight into the Light-Irradiated Carbon Capsules as an Antibacterial Agent. ACS APPLIED MATERIALS & INTERFACES 2018; 10:25026-25036. [PMID: 29989399 DOI: 10.1021/acsami.8b04932] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Infections caused by bacteria are a growing global challenge for public health as bacteria develop resistance, which will cause the failure of anti-infective treatment eventually. An effective alternative strategy to traditional antibacterial therapy is utilizing reactive oxygen species (ROS) to kill bacteria. Here, we report a simple route to prepare PEGylated nitrogen-doped carbon capsules (PEG-N-CCs) as an antibacterial agent. The PEG-N-CCs can translate near-infrared light (NIR) into heat and produce a high concentration of ROS triggered by NIR irradiation. Both heating and ROS are critical to destroy the outer membranes and rupture cell bodies, causing DNA fragmentation and glutathione oxidation both in Gram-negative Escherichia coli, Gram-positive Staphylococcus aureus, and their multidrug-resistant strains. Moreover, PEG-N-CCs plus NIR irradiation can efficiently scavenge the existing biofilms and prevent the formation of new biofilms, killing planktonic bacteria as well as those within the biofilm. Our studies prove that the PEG-N-CCs plus NIR irradiation can provide a simple and effective platform for combating bacteria, employing carbon nanomaterials as an antibacterial alternative for treatment of infectious diseases.
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Affiliation(s)
- Qiuwen Wu
- Department of Pharmacology, Institute of Translational Medicine, School of Medicine , Yangzhou University , Yangzhou 225001 , Jiangsu , China
| | - Gen Wei
- Department of Pharmacology, Institute of Translational Medicine, School of Medicine , Yangzhou University , Yangzhou 225001 , Jiangsu , China
| | - Zhuobin Xu
- Department of Pharmacology, Institute of Translational Medicine, School of Medicine , Yangzhou University , Yangzhou 225001 , Jiangsu , China
| | - Jing Han
- Department of Pharmacology, Institute of Translational Medicine, School of Medicine , Yangzhou University , Yangzhou 225001 , Jiangsu , China
| | - Juqun Xi
- Department of Pharmacology, Institute of Translational Medicine, School of Medicine , Yangzhou University , Yangzhou 225001 , Jiangsu , China
- Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases , Yangzhou 225001 , Jiangsu , China
| | - Lei Fan
- School of Chemistry and Chemical Engineering , Yangzhou University , Yangzhou 225002 , Jiangsu , China
| | - Lizeng Gao
- Department of Pharmacology, Institute of Translational Medicine, School of Medicine , Yangzhou University , Yangzhou 225001 , Jiangsu , China
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16
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Impact of glutathione peroxidase 4 on cell proliferation, angiogenesis and cytokine production in hepatocellular carcinoma. Oncotarget 2018. [PMID: 29515790 PMCID: PMC5839371 DOI: 10.18632/oncotarget.24300] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Insufficient supplementation with the micronutrient selenium and persistent hepatic inflammation predispose to hepatocellular carcinoma (HCC). Inflammation-associated reactive oxygen species attack membrane lipids and form lipid hydroperoxides able to propagate oxidative hepatic damage. Selenium-containing enzyme glutathione peroxidase 4 (GPx4) antagonizes this damage by reducing lipid hydroperoxides to respective hydroxides. However, the role of GPx4 in HCC remains elusive. We generated two human HCC cell lines with stable overexpression of GPx4, performed xenotransplantation into NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) host mice and characterized the tumors formed. The experimental data were verified using gene expression data from two independent HCC patient cohorts. GPx4 overexpression protected from oxidative stress and reduced intracellular free radical level. GPx4-overexpressing cells displayed impaired tumor growth, reduced proliferation, altered angiogenesis and decreased expression of clinically relevant cytokine interleukin-8 and C-reactive protein. Moreover, GPx4 overexpression impaired migration of endothelial cells in vitro, and enhanced expression of thrombospondin 1, an endogenous inhibitor of angiogenesis. In patients, GPx4 expression in tumors positively correlated with survival and was linked to pathways which regulate cell proliferation, motility, tissue remodelling, immune response and M1 macrophage polarization. The patient data largely confirmed experimental findings especially in a subclass of poor prognosis tumors with high proliferation. GPx4 suppresses formation and progression of HCC by inhibition of angiogenesis and tumor cell proliferation as well as by immune-mediated mechanisms. Modification of GPx4 expression may represent a novel tool for HCC prevention or treatment.
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17
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Kuresepi S, Vileno B, Turek P, Lepoittevin JP, Giménez-Arnau E. Potential of EPR spin-trapping to investigate in situ free radicals generation from skin allergens in reconstructed human epidermis: cumene hydroperoxide as proof of concept. Free Radic Res 2018; 52:171-179. [DOI: 10.1080/10715762.2017.1420906] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Salen Kuresepi
- Dermatochemistry Laboratory, University of Strasbourg, CNRS UMR 7177, Institut le Bel, Strasbourg, France
| | - Bertrand Vileno
- POMAM Laboratory, University of Strasbourg, CNRS UMR 7177, Institut le Bel, Strasbourg, France
- French EPR Federation of Research, REseau NAtional de Rpe interDisciplinaire, RENARD, Fédération IR-RPE CNRS #3443, Strasbourg, France
| | - Philippe Turek
- POMAM Laboratory, University of Strasbourg, CNRS UMR 7177, Institut le Bel, Strasbourg, France
- French EPR Federation of Research, REseau NAtional de Rpe interDisciplinaire, RENARD, Fédération IR-RPE CNRS #3443, Strasbourg, France
| | - Jean-Pierre Lepoittevin
- Dermatochemistry Laboratory, University of Strasbourg, CNRS UMR 7177, Institut le Bel, Strasbourg, France
| | - Elena Giménez-Arnau
- Dermatochemistry Laboratory, University of Strasbourg, CNRS UMR 7177, Institut le Bel, Strasbourg, France
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18
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Rohr-Udilova N, Klinglmüller F, Seif M, Hayden H, Bilban M, Pinter M, Stolze K, Sieghart W, Peck-Radosavljevic M, Trauner M. Oxidative stress mediates an increased formation of vascular endothelial growth factor in human hepatocarcinoma cells exposed to erlotinib. Oncotarget 2017; 8:57109-57120. [PMID: 28915658 PMCID: PMC5593629 DOI: 10.18632/oncotarget.19055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 06/19/2017] [Indexed: 02/05/2023] Open
Abstract
The tyrosine kinase inhibitor erlotinib targets the receptor of epidermal growth factor (EGFR) involved in development of hepatocellular carcinoma (HCC). Although inefficient in established HCC, erlotinib has been recently proposed for HCC chemoprevention. Since Cyp3A4 and Cyp1A2 enzymes metabolize erlotinib in the liver, the insights into the mechanisms of erlotinib effects on liver cells with maintained drug metabolizing activity are needed. We applied erlotinib to both commercially available (SNU398, Huh7) and established in Austria HCC cell lines (HCC-1.2, HCC-3). Cyp3A4 and Cyp1A2, microarray gene expression, cell viability, LDH release, DHFC fluorescence were assessed. VEGF expression was analysed by real-time RT-PCR and ELISA. Higher cumulative expression of erlotinib metabolizing enzymes was observed in HCC-1.2 and HCC-3 cells. Gene expression microarray analysis showed upregulation of VEGF signalling by erlotinib. VEGF was increased up to 134 ± 14% (n = 5, p = 0.002) in HCC-1.2, HCC-3 and Huh7 cells. Interventions by Cyp1A2 and Mek2siRNA, MEK inhibitor UO126, diphenylene iodonium, as well as a combination of N-acetylcysteine with selenium all inhibited VEGF upregulation caused by erlotinib. Thus, erlotinib increases VEGF production by mechanisms involving Cyp1A2, oxidative stress and MEK1/2. VEGF may favour angiogenesis and growth of early HCC tumours limiting the therapeutic and chemopreventive effects of erlotinib.
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Affiliation(s)
- Nataliya Rohr-Udilova
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090 Vienna, Austria
| | - Florian Klinglmüller
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, A-1090 Vienna, Austria
| | - Martha Seif
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090 Vienna, Austria
| | - Hubert Hayden
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090 Vienna, Austria
| | - Martin Bilban
- Clinical Institute for Laboratory Medicine, Medical University of Vienna, A-1090 Vienna, Austria
| | - Matthias Pinter
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090 Vienna, Austria
| | - Klaus Stolze
- Institute of Animal Nutrition and Functional Plant Compounds, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine, A-1220 Vienna, Austria
| | - Wolfgang Sieghart
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090 Vienna, Austria
| | - Markus Peck-Radosavljevic
- Clinic Klagenfurth, Division of Gastroenterology and Hepatology, 9020 Klagenfurt am Wörthersee, Austria
| | - Michael Trauner
- Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Medical University of Vienna, A-1090 Vienna, Austria
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19
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Davies MJ. Detection and characterisation of radicals using electron paramagnetic resonance (EPR) spin trapping and related methods. Methods 2016; 109:21-30. [DOI: 10.1016/j.ymeth.2016.05.013] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 05/17/2016] [Accepted: 05/18/2016] [Indexed: 12/16/2022] Open
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20
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Chong Y, Ge C, Fang G, Tian X, Ma X, Wen T, Wamer WG, Chen C, Chai Z, Yin JJ. Crossover between Anti- and Pro-oxidant Activities of Graphene Quantum Dots in the Absence or Presence of Light. ACS NANO 2016; 10:8690-8699. [PMID: 27584033 DOI: 10.1021/acsnano.6b04061] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Graphene quantum dots (GQDs), zero-dimensional carbon materials displaying excellent luminescence properties, show great promise for medical applications such as imaging, drug delivery, biosensors, and novel therapeutics. A deeper understanding of how the properties of GQDs interact with biological systems is essential for these applications. Our work demonstrates that GQDs can efficiently scavenge a number of free radicals and thereby protect cells against oxidative damage. However, upon exposure to blue light, GQDs exhibit significant phototoxicity through increasing intracellular reactive oxygen species (ROS) levels and reducing cell viability, attributable to the generation of free radicals under light excitation. We confirm that light-induced formation of ROS originates from the electron-hole pair and, more importantly, reveal that singlet oxygen is generated by photoexcited GQDs via both energy-transfer and electron-transfer pathways. Moreover, upon light excitation, GQDs accelerate the oxidation of non-enzymic anti-oxidants and promote lipid peroxidation, contributing to the phototoxicity of GQDs. Our results reveal that GQDs can display both anti- and pro-oxidant activities, depending upon light exposure, which will be useful in guiding the safe application and development of potential anticancer/antibacterial applications for GQDs.
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Affiliation(s)
- Yu Chong
- School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University , Suzhou 215123, China
- Division of Bioanalytical Chemistry and Division of Analytical Chemistry, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , College Park, Maryland 20740, United States
| | - Cuicui Ge
- School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University , Suzhou 215123, China
- Division of Bioanalytical Chemistry and Division of Analytical Chemistry, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , College Park, Maryland 20740, United States
| | - Ge Fang
- School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University , Suzhou 215123, China
| | - Xin Tian
- School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University , Suzhou 215123, China
| | - Xiaochuan Ma
- School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University , Suzhou 215123, China
| | - Tao Wen
- Division of Bioanalytical Chemistry and Division of Analytical Chemistry, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , College Park, Maryland 20740, United States
| | - Wayne G Wamer
- Division of Bioanalytical Chemistry and Division of Analytical Chemistry, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , College Park, Maryland 20740, United States
| | - Chunying Chen
- Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology of China and Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100190, China
| | - Zhifang Chai
- School for Radiological and Interdisciplinary Sciences (RAD-X), Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University , Suzhou 215123, China
- Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology of China and Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100190, China
| | - Jun-Jie Yin
- Division of Bioanalytical Chemistry and Division of Analytical Chemistry, Office of Regulatory Science, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration , College Park, Maryland 20740, United States
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21
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Li H, Wan J, Ma Y, Wang Y. Reaction pathway and oxidation mechanisms of dibutyl phthalate by persulfate activated with zero-valent iron. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 562:889-897. [PMID: 27125682 DOI: 10.1016/j.scitotenv.2016.04.093] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 04/12/2016] [Accepted: 04/13/2016] [Indexed: 06/05/2023]
Abstract
This study investigated reaction pathway and oxidation mechanisms of dibutyl phthalate (DBP) by persulfate (PS) activated with zero-valent iron (ZVI). The DBP degradation was studied at three pH values (acidic, neutral and basic) in the presence of different organic scavengers. Using a chemical probe method, both sulfate radical (SO4(-)) and hydroxyl radical (·OH) were found to be primary oxidants at pH3.0 and pH7.0, respectively while ·OH was the major specie to oxidize DBP at pH11.0. A similar result was found in an experiment of Electron Spin Resonance spin-trapping where in addition to OH, superoxide radical (O2(-)) was detected at pH11.0. The transformation of degradation products including dimethyl phthalate (DMP), diethyl phthalate (DEP), phthalic anhydride, and acetophenone exhibited diverse variation during the reaction processes. The phthalic anhydride concentration appeared to be maximum at all pHs. Another eleven intermediate products were also found at pH3.0 by GC-MS and HPLC analysis, and their degradation mechanisms and pathways were proposed. It was suggested that dealkylation, hydroxylation, decarboxylation and hydrogen extraction were the dominant degradation mechanisms of DBP at pH3.0.
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Affiliation(s)
- Huanxuan Li
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China, Guangzhou 510640, PR China
| | - Jinquan Wan
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China, Guangzhou 510640, PR China; State Key Lab Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, PR China.
| | - Yongwen Ma
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China, Guangzhou 510640, PR China; State Key Lab Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Yan Wang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China, Guangzhou 510640, PR China
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22
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UV-induced reactions of Mg 2+ -doped anatase nanocrystals with exposed {0 0 1} facets: An EPR study. J Catal 2015. [DOI: 10.1016/j.jcat.2015.08.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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23
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Terzić V, Padovani D, Balland V, Artaud I, Galardon E. Electrophilic sulfhydration of 8-nitro-cGMP involves sulfane sulfur. Org Biomol Chem 2015; 12:5360-4. [PMID: 24955554 DOI: 10.1039/c4ob00868e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The formation of 8-SH-cGMP from the reaction between hydrogen sulfide and 8-nitro-guanosine-3',5'-cyclic monophosphate in the presence of thiols does not take place by nucleophilic attack of the hydrosulfide anion, as previously proposed, but first involves the formation of reactive species containing sulfane sulfur, like persulfides.
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Affiliation(s)
- V Terzić
- UMR 8601, LCBPT, CNRS-Université Paris Descartes, Sorbonne Paris Cité, 45 rue des Sts Pères, 75006 Paris, France.
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24
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Zhu X, Niu X, Zhao H, Tang J, Lan M. Immobilization of superoxide dismutase on Pt–Pd/MWCNTs hybrid modified electrode surface for superoxide anion detection. Biosens Bioelectron 2015; 67:79-85. [DOI: 10.1016/j.bios.2014.07.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 07/03/2014] [Accepted: 07/03/2014] [Indexed: 12/21/2022]
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25
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Wen T, He W, Chong Y, Liu Y, Yin JJ, Wu X. Exploring environment-dependent effects of Pd nanostructures on reactive oxygen species (ROS) using electron spin resonance (ESR) technique: implications for biomedical applications. Phys Chem Chem Phys 2015; 17:24937-43. [DOI: 10.1039/c5cp04046a] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pd nanostructures can promote the decomposition of H2O2 in a pH-dependent manner and scavenge superoxide and singlet oxygen.
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Affiliation(s)
- Tao Wen
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- National Center for Nanoscience and Technology
- Beijing 100190, P. R. China
- Division of Analytical Chemistry
- Office of Regulatory Science
| | - Weiwei He
- Division of Analytical Chemistry
- Office of Regulatory Science
- Center for Food Safety and Applied Nutrition
- US Food and Drug Administration
- College Park 20740, USA
| | - Yu Chong
- Division of Analytical Chemistry
- Office of Regulatory Science
- Center for Food Safety and Applied Nutrition
- US Food and Drug Administration
- College Park 20740, USA
| | - Yi Liu
- Division of Analytical Chemistry
- Office of Regulatory Science
- Center for Food Safety and Applied Nutrition
- US Food and Drug Administration
- College Park 20740, USA
| | - Jun-Jie Yin
- Division of Analytical Chemistry
- Office of Regulatory Science
- Center for Food Safety and Applied Nutrition
- US Food and Drug Administration
- College Park 20740, USA
| | - Xiaochun Wu
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology
- National Center for Nanoscience and Technology
- Beijing 100190, P. R. China
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26
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Yaghini E, Pirker KF, Kay CWM, Seifalian AM, MacRobert AJ. Quantification of reactive oxygen species generation by photoexcitation of PEGylated quantum dots. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:5106-5115. [PMID: 25164061 DOI: 10.1002/smll.201401209] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/20/2014] [Indexed: 06/03/2023]
Abstract
Photocatalytic generation of reactive oxygen species (ROS) from quantum dots (QDs) has been widely reported yet quantitative studies of ROS formation and their quantum yields are lacking. This study investigates the generation of ROS by water soluble PEGylated CdSe/ZnS QDs with red emission. PEGylation of QDs is commonly used to confer water solubility and minimise uptake by organs of the reticuloendothelial system; therefore studies of ROS formation are of biomedical relevance. Using non-photolytic visible wavelength excitation, the superoxide anion radical is shown to be the primary ROS species generated with a quantum efficiency of 0.35%. The yield can be significantly enhanced in the presence of the electron donor, nicotinamide adenine dinucleotide (NADH), as demonstrated by oxygen consumption measurements and electron paramagnetic resonance spectroscopy with in situ illumination. Direct production of singlet oxygen is not detectable from the QDs alone. A comparison is made with ROS generation by the same QDs complexed with a sulfonated phthalocyanine which can generate singlet oxygen via Förster resonance energy transfer between the QDs and the phthalocyanine.
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Affiliation(s)
- Elnaz Yaghini
- Division of Surgery & Interventional Science, Charles Bell House, University College London, London, W1W 7EJ, UK
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27
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Polotow TG, Vardaris CV, Mihaliuc AR, Gonçalves MS, Pereira B, Ganini D, Barros MP. Astaxanthin supplementation delays physical exhaustion and prevents redox imbalances in plasma and soleus muscles of Wistar rats. Nutrients 2014; 6:5819-38. [PMID: 25514562 PMCID: PMC4277001 DOI: 10.3390/nu6125819] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 11/06/2014] [Accepted: 11/13/2014] [Indexed: 01/21/2023] Open
Abstract
Astaxanthin (ASTA) is a pinkish-orange carotenoid commonly found in marine organisms, especially salmon. ASTA is a powerful antioxidant and suggested to provide benefits for human health, including the inhibition of LDL oxidation, UV-photoprotection, and prophylaxis of bacterial stomach ulcers. Exercise is associated to overproduction of free radicals in muscles and plasma, with pivotal participation of iron ions and glutathione (GSH). Thus, ASTA was studied here as an auxiliary supplement to improve antioxidant defenses in soleus muscles and plasma against oxidative damage induced by exhaustive exercise. Long-term 1 mg ASTA/kg body weight (BW) supplementation in Wistar rats (for 45 days) significantly delayed time to exhaustion by 29% in a swimming test. ASTA supplementation increased scavenging/iron-chelating capacities (TEAC/FRAP) and limited exercise-induced iron overload and its related pro-oxidant effects in plasma of exercising animals. On the other hand, ASTA induced significant mitochondrial Mn-dependent superoxide dismutase and cytosolic glutathione peroxidase antioxidant responses in soleus muscles that, in turn, increased GSH content during exercise, limited oxidative stress, and delayed exhaustion. We also provided significant discussion about a putative "mitochondrial-targeted" action of ASTA based on previous publications and on the positive results found in the highly mitochondrial populated (oxidative-type) soleus muscles here.
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Affiliation(s)
- Tatiana G Polotow
- Institute of Physical Activity and Sports Sciences (ICAFE), Cruzeiro do Sul University, 01506-000 Sao Paulo, Brazil.
| | - Cristina V Vardaris
- Institute of Physical Activity and Sports Sciences (ICAFE), Cruzeiro do Sul University, 01506-000 Sao Paulo, Brazil.
| | - Andrea R Mihaliuc
- Institute of Physical Activity and Sports Sciences (ICAFE), Cruzeiro do Sul University, 01506-000 Sao Paulo, Brazil.
| | - Marina S Gonçalves
- Institute of Physical Activity and Sports Sciences (ICAFE), Cruzeiro do Sul University, 01506-000 Sao Paulo, Brazil.
| | - Benedito Pereira
- School of Physical Education and Sports (EEFE), University of Sao Paulo (USP), 05508-900 Sao Paulo, Brazil.
| | - Douglas Ganini
- Institute of Physical Activity and Sports Sciences (ICAFE), Cruzeiro do Sul University, 01506-000 Sao Paulo, Brazil.
| | - Marcelo P Barros
- Institute of Physical Activity and Sports Sciences (ICAFE), Cruzeiro do Sul University, 01506-000 Sao Paulo, Brazil.
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28
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Liu Y, Wu H, Li M, Yin JJ, Nie Z. pH dependent catalytic activities of platinum nanoparticles with respect to the decomposition of hydrogen peroxide and scavenging of superoxide and singlet oxygen. NANOSCALE 2014; 6:11904-11910. [PMID: 25175625 DOI: 10.1039/c4nr03848g] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Recently, platinum (Pt) nanoparticles (NPs) have received increasing attention in the field of catalysis and medicine due to their excellent catalytic activity. To rationally design Pt NPs for these applications, it is crucial to understand the mechanisms underlying their catalytic and biological activities. This article describes a systematic study on the Pt NP-catalyzed decomposition of hydrogen peroxide (H2O2) and scavenging of superoxide (O2˙(-)) and singlet oxygen ((1)O2) over a physiologically relevant pH range of 1.12-10.96. We demonstrated that the catalytic activities of Pt NPs can be modulated by the pH value of the environment. Our results suggest that Pt NPs possess peroxidase-like activity of decomposing H2O2 into ˙OH under acidic conditions, but catalase-like activity of producing H2O and O2 under neutral and alkaline conditions. In addition, Pt NPs exhibit significant superoxide dismutase-like activity of scavenging O2˙(-) under neutral conditions, but not under acidic conditions. The (1)O2 scavenging ability of Pt NPs increases with the increase in the pH of the environment. The study will provide useful guidance for designing Pt NPs with desired catalytic and biological properties.
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Affiliation(s)
- Yi Liu
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
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Anderson RF, Yadav P, Patel D, Reynisson J, Tipparaju SR, Guise CP, Patterson AV, Denny WA, Maroz A, Shinde SS, Hay MP. Characterisation of radicals formed by the triazine 1,4-dioxide hypoxia-activated prodrug, SN30000. Org Biomol Chem 2014; 12:3386-92. [PMID: 24737463 DOI: 10.1039/c4ob00236a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The radical species underlying the activity of the bioreductive anticancer prodrug, SN30000, have been identified by electron paramagnetic resonance and pulse radiolysis techniques. Spin-trapping experiments indicate both an aryl-type radical and an oxidising radical, trapped as a carbon-centred radical, are formed from the protonated radical anion of SN30000. The carbon-centred radical, produced upon the one-electron oxidation of the 2-electron reduced metabolite of SN30000, oxidises 2-deoxyribose, a model for the site of damage on DNA which leads to double strand breaks. Calculations using density functional theory support the assignments made.
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Affiliation(s)
- Robert F Anderson
- Auckland Cancer Society Research Centre, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
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Dong J, Song L, Yin JJ, He W, Wu Y, Gu N, Zhang Y. Co₃O₄ nanoparticles with multi-enzyme activities and their application in immunohistochemical assay. ACS APPLIED MATERIALS & INTERFACES 2014; 6:1959-1970. [PMID: 24387092 DOI: 10.1021/am405009f] [Citation(s) in RCA: 258] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Co3O4 nanoparticles (Co3O4 NPs), synthesized by the coprecipitation method, showed intrinsic catalase-like, peroxidase-like, and SOD-like activity. The catalytic activity of Co3O4 NPs was much higher than analogous Fe3O4 NPs. Co3O4's mechanisms of catalytic activity were analyzed in detail using the electron spin resonance (ESR) method, which confirmed that Co3O4 NPs don't follow the classical Fenton reactions with hydrogen peroxide the way Fe3O4 NPs do. The high redox potential of Co(3+)/Co(2+) was supposed to be the leading cause of the differences in both activity and mechanism with Fe3O4. Based on the high, peroxidase-like activity, a new immunohistochemical assay was designed in which the avastin antibody was conjugated onto the surface of Co3O4 NPs. The conjugates obtained were used to detect vascular endothelial growth factor (VEGF) that was overexpressed in tumor tissue. When the experimental and control groups were stained, there were clear distinctions between them. This study showed that there are many opportunities to improve the enzyme-like activities of nanomaterials and also to improve their potential applications for biocatalysis and bioassays, especially in relatively harsh conditions.
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Affiliation(s)
- Jinlai Dong
- State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, P.R. China
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31
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Hawkins CL, Davies MJ. Detection and characterisation of radicals in biological materials using EPR methodology. Biochim Biophys Acta Gen Subj 2014; 1840:708-21. [DOI: 10.1016/j.bbagen.2013.03.034] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 03/28/2013] [Indexed: 12/21/2022]
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Protection against peroxynitrite-induced DNA damage by mesalamine: implications for anti-inflammation and anti-cancer activity. Mol Cell Biochem 2013; 378:291-8. [PMID: 23529546 DOI: 10.1007/s11010-013-1620-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 03/02/2013] [Indexed: 12/21/2022]
Abstract
Mesalamine (5-aminosalicylic acid, 5-ASA) is known to be the first-line medication for treatment of patients with ulcerative colitis. Studies have demonstrated that ulcerative colitis patients treated with 5-ASA have an overall decrease in the risk of developing colorectal carcinoma. However, the mechanisms underlying 5-ASA-mediated anti-inflammatory and anti-cancer effects are yet to be elucidated. Because peroxynitrite has been critically involved in inflammatory stress and carcinogenesis, this study was undertaken to investigate the effects of 5-ASA in peroxynitrite-induced DNA strand breaks, an important event leading to peroxynitrite-elicited cytotoxicity. Incubation of φX-174 plasmid DNA with the peroxynitrite generator 3-morpholinosydnonimine (SIN-1) led to the formation of both single- and double-stranded DNA breaks in a concentration-dependent manner. The presence of 5-ASA at 0.1 and 1.0 mM was found to significantly inhibit SIN-1-induced DNA strand breaks in a concentration-dependent manner. The consumption of oxygen induced by SIN-1 was found to not be affected by 5-ASA at 0.1-50 mM, indicating that 5-ASA at these concentrations is not involved in the auto-oxidation of SIN-1 to form peroxynitrite. It is observed that 5-ASA at 0.1-1 mM showed considerable inhibition of peroxynitrite-mediated luminol chemiluminescence in a dose-dependent fashion, suggesting that 5-ASA is able to directly scavenge the peroxynitrite. Electron paramagnetic resonance (EPR) spectroscopy in combination with spin-trapping experiments, using 5,5-dimethylpyrroline-N-oxide (DMPO) as spin trap resulting in the formation of DMPO-hydroxyl radical adduct from peroxynitrite, and 5-ASA only at higher concentration (1 mM) inhibited the hydroxyl radical adduct while shifting EPR spectra, indicating that 5-ASA at higher concentrations may generate a more stable free radical species rather than acting purely as a hydroxyl radical scavenger. Taken together, these studies demonstrate for the first time that 5-ASA can potently inhibit peroxynitrite-mediated DNA strand breakage, scavenge peroxynitrite, and affect peroxynitrite-mediated radical formation, which may be responsible, at least partially, for its anti-inflammatory and anti-cancer effects.
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Intrinsic catalytic activity of Au nanoparticles with respect to hydrogen peroxide decomposition and superoxide scavenging. Biomaterials 2013; 34:765-73. [DOI: 10.1016/j.biomaterials.2012.10.010] [Citation(s) in RCA: 253] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 10/04/2012] [Indexed: 12/11/2022]
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Potential implication of the chemical properties and bioactivity of nitrone spin traps for therapeutics. Future Med Chem 2012; 4:1171-207. [PMID: 22709256 DOI: 10.4155/fmc.12.74] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Nitrone therapeutics has been employed in the treatment of oxidative stress-related diseases such as neurodegeneration, cardiovascular disease and cancer. The nitrone-based compound NXY-059, which is the first drug to reach clinical trials for the treatment of acute ischemic stroke, has provided promise for the development of more robust pharmacological agents. However, the specific mechanism of nitrone bioactivity remains unclear. In this review, we present a variety of nitrone chemistry and biological activity that could be implicated for the nitrone's pharmacological activity. The chemistries of spin trapping and spin adduct reveal insights on the possible roles of nitrones for altering cellular redox status through radical scavenging or nitric oxide donation, and their biological effects are presented. An interdisciplinary approach towards the development of novel synthetic antioxidants with improved pharmacological properties encompassing theoretical, synthetic, biochemical and in vitro/in vivo studies is covered.
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Stenuit B, Lamblin G, Cornelis P, Agathos SN. Aerobic denitration of 2,4,6-trinitrotoluene in the presence of phenazine compounds and reduced pyridine nucleotides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:10605-10613. [PMID: 22881832 DOI: 10.1021/es302046h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Phenazine-containing spent culture supernatants of Pseudomonas aeruginosa concentrated with a C18 solid-phase extraction cartridge initiate NAD(P)H-dependent denitration of 2,4,6-trinitrotoluene (TNT). In this study, TNT denitration was investigated under aerobic conditions using two phenazine secondary metabolites excreted by P. aeruginosa, pyocyanin (Py) and its precursor phenazine-1- carboxylic acid (PCA), and two chemically synthesized pyocyanin analogs, phenazine methosulfate (PMS+) and phenazine ethosulfate (PES+). The biomimetic Py/NAD(P)H/O2 system was characterized and found to extensively denitrate TNT in unbuffered aqueous solution with minor production of toxic amino aromatic derivatives. To a much lesser extent, TNT denitration was also observed with PMS+ and PES+ in the presence of NAD(P)H. No TNT denitration was detected with the biomimetic PCA/NAD(P)H/O2 system. Electron paramagnetic resonance (EPR) spectroscopy analysis of the biomimetic Py/NAD(P)H/O2 system revealed the generation of superoxide radical anions (O2 •−). In vitro TNT degradation experiments in the presence of specific inhibitors of reactive oxygen species suggest a nucleophilic attack of superoxide radical anion followed by TNT denitration through an as yet unknown mechanism. The results of this research confirm the high functional versatility of the redox-active metabolite pyocyanin and the susceptibility of aromatic compounds bearing electron withdrawing substituents, such as nitro groups, to superoxide-driven nucleophilic attack.
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Affiliation(s)
- Ben Stenuit
- Earth and Life Institute, Laboratory of Bioengineering, Université Catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
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Tsai CY, Finley JC, Ali SS, Patel HH, Howell SB. Copper influx transporter 1 is required for FGF, PDGF and EGF-induced MAPK signaling. Biochem Pharmacol 2012; 84:1007-13. [PMID: 22842628 DOI: 10.1016/j.bcp.2012.07.014] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 07/16/2012] [Accepted: 07/17/2012] [Indexed: 12/20/2022]
Abstract
Copper transporter 1 (CTR1) is the major copper (Cu) influx transporter in mammalian cells. We report here that CTR1 is required for the activation of signaling to the MAPK pathway by the ligands of three major receptor tyrosine kinases (RTK) including FGF, PDGF and EGF. Induction of Erk1/2 phosphorylation was compared in isogenic wild type CTR1(+/+) and CTR1(-/-) cells. Whereas all three ligands increased pErk1/2 in the CTR1(+/+) cells, they failed to do this in CTR1(-/-) cells. While FGF did not enhance the phosphorylation of AKT in the CTR1(+/+) cells, both PDGF and EGF increased pAKT in the CTR1(+/+) but not CTR1(-/-) cells. The deficit in Erk1/2 phosphorylation in the CTR1(-/-) cells was rescued by adding Cu to the medium, and it was induced in CTR1(+/+) cells by treatment with a Cu chelator. Intracellular Cu availability was reduced in the CTR1(-/-) cells as reflected by increased expression of the Cu chaperone CCS. The failure of RTK-induced signaling to both Erk1/2 and AKT suggested the presence of a Cu-dependent step upstream of Ras. The Cu-dependent enzyme SOD1 is responsible for generating the hydrogen peroxide in response to RTK activation that serves to inhibit phosphatases that normally limit RTK signaling. SOD1 activity was reduced by a factor of 17-fold in the CTR1(-/-) cells, and addition of hydrogen peroxide restored signaling. We conclude that Cu acquired from CTR1 is required for signaling in pathways regulated by RTKs that play major roles in development and cancer.
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Affiliation(s)
- Cheng-Yu Tsai
- The Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
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Yno1p/Aim14p, a NADPH-oxidase ortholog, controls extramitochondrial reactive oxygen species generation, apoptosis, and actin cable formation in yeast. Proc Natl Acad Sci U S A 2012; 109:8658-63. [PMID: 22586098 DOI: 10.1073/pnas.1201629109] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The large protein superfamily of NADPH oxidases (NOX enzymes) is found in members of all eukaryotic kingdoms: animals, plants, fungi, and protists. The physiological functions of these NOX enzymes range from defense to specialized oxidative biosynthesis and to signaling. In filamentous fungi, NOX enzymes are involved in signaling cell differentiation, in particular in the formation of fruiting bodies. On the basis of bioinformatics analysis, until now it was believed that the genomes of unicellular fungi like Saccharomyces cerevisiae and Schizosaccharomyces pombe do not harbor genes coding for NOX enzymes. Nevertheless, the genome of S. cerevisiae contains nine ORFs showing sequence similarity to the catalytic subunits of mammalian NOX enzymes, only some of which have been functionally assigned as ferric reductases involved in iron ion transport. Here we show that one of the nine ORFs (YGL160W, AIM14) encodes a genuine NADPH oxidase, which is located in the endoplasmic reticulum (ER) and produces superoxide in a NADPH-dependent fashion. We renamed this ORF YNO1 (yeast NADPH oxidase 1). Overexpression of YNO1 causes YCA1-dependent apoptosis, whereas deletion of the gene makes cells less sensitive to apoptotic stimuli. Several independent lines of evidence point to regulation of the actin cytoskeleton by reactive oxygen species (ROS) produced by Yno1p.
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Ali SS, Hsiao M, Zhao HW, Dugan LL, Haddad GG, Zhou D. Hypoxia-adaptation involves mitochondrial metabolic depression and decreased ROS leakage. PLoS One 2012; 7:e36801. [PMID: 22574227 PMCID: PMC3344937 DOI: 10.1371/journal.pone.0036801] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 04/13/2012] [Indexed: 11/19/2022] Open
Abstract
Through long-term laboratory selection, we have generated a Drosophila melanogaster population that tolerates severe, normally lethal, level of hypoxia. This strain lives perpetually under severe hypoxic conditions (4% O(2)). In order to shed light on the mechanisms involved in this adaptation, we studied the respiratory function of isolated mitochondria from the thorax of hypoxia-adapted flies (AF) using polarographic oxygen consumption while monitoring superoxide generation by electron paramagnetic resonance (EPR) techniques. AF mitochondria exhibited a significant 30% decrease in respiratory rate during state 3, while enhancing the resting respiratory rate during State 4-oligo by 220%. The activity of individual electron transport complexes I, II and III were 107%, 65%, and 120% in AF mitochondria as compared to those isolated from control flies. The sharp decrease in complex II activity and modest increase in complexes I and III resulted in >60% reduction in superoxide leakage from AF mitochondria during both NAD(+)-linked state 3 and State 4-oligo respirations. These results provide evidence that flies with mitochondria exhibiting decreased succinate dehydrogenase activity and reduced superoxide leakage give flies an advantage for survival in long-term hypoxia.
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Affiliation(s)
- Sameh S. Ali
- Department of Medicine, University of California San Diego, San Diego, California, United States of America
- The Center for Aging and Associated Diseases, Helmy Institute of Medical Sciences, Zewail City of Science and Technology, Giza, Egypt
- * E-mail: (SSA); (DZ)
| | - Mary Hsiao
- Department of Pediatrics, University of California San Diego, San Diego, California, United States of America
| | - Huiwen W. Zhao
- Department of Pediatrics, University of California San Diego, San Diego, California, United States of America
| | - Laura L. Dugan
- Department of Medicine, University of California San Diego, San Diego, California, United States of America
- Department of Neuroscience, University of California San Diego, San Diego, California, United States of America
| | - Gabriel G. Haddad
- Department of Pediatrics, University of California San Diego, San Diego, California, United States of America
- Department of Neuroscience, University of California San Diego, San Diego, California, United States of America
- Rady Children's Hospital-San Diego, San Diego, California, United States of America
| | - Dan Zhou
- Department of Pediatrics, University of California San Diego, San Diego, California, United States of America
- * E-mail: (SSA); (DZ)
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Rohr-Udilova N, Sieghart W, Eferl R, Stoiber D, Björkhem-Bergman L, Eriksson LC, Stolze K, Hayden H, Keppler B, Sagmeister S, Grasl-Kraupp B, Schulte-Hermann R, Peck-Radosavljevic M. Antagonistic effects of selenium and lipid peroxides on growth control in early hepatocellular carcinoma. Hepatology 2012; 55:1112-21. [PMID: 22105228 DOI: 10.1002/hep.24808] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
UNLABELLED Activation of the activator protein 1 (AP-1) transcription factor as well as increased serum levels of vascular endothelial growth factor (VEGF) and interleukin (IL)-8 predict poor prognosis of patients with hepatocellular carcinomas (HCCs). Moreover, HCC patients display reduced selenium levels, which may cause lipid peroxidation and oxidative stress because selenium is an essential component of antioxidative glutathione peroxidases (GPx). We hypothesized that selenium-lipid peroxide antagonism controls the above prognostic markers and tumor growth. (1) In human HCC cell lines (HCC-1.2, HCC-3, and SNU398) linoleic acid peroxide (LOOH) and other prooxidants enhanced the expression of VEGF and IL-8. LOOH up-regulated AP-1 activation. Selenium inhibited these effects. This inhibition was mediated by glutathione peroxidase 4 (GPx4), which preferentially degrades lipid peroxides. Selenium enhanced GPx4 expression and total GPx activity, while knock-down of GPx4 by small interfering RNA (siRNA) increased VEGF, and IL-8 expression. (2) These results were confirmed in a rat hepatocarcinogenesis model. Selenium treatment during tumor promotion increased hepatic GPx4 expression and reduced the expression of VEGF and of the AP-1 component c-fos as well as nodule growth. (3) In HCC patients, increased levels of LOOH-related antibodies (LOOH-Ab) were found, suggesting enhanced LOOH formation. LOOH-Ab correlated with serum VEGF and IL-8 and with AP-1 activation in HCC tissue. In contrast, selenium inversely correlated with VEGF, IL-8, and HCC size (the latter only for tumors smaller than 3 cm). CONCLUSION Reduced selenium levels result in accumulation of lipid peroxides. This leads to enhanced AP-1 activation and consequently to elevated expression of VEGF and IL-8, which accelerate the growth of HCC. Selenium supplementation could be considered for investigation as a strategy for chemoprevention or additional therapy of early HCC in patients with low selenium levels.
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Affiliation(s)
- Nataliya Rohr-Udilova
- Division of Gastroenterology and Hepatology, Internal Medicine III, Medical University of Vienna, Vienna, Austria
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Pamenter ME, Ali SS, Tang Q, Finley JC, Gu XQ, Dugan LL, Haddad GG. An in vitro ischemic penumbral mimic perfusate increases NADPH oxidase-mediated superoxide production in cultured hippocampal neurons. Brain Res 2012; 1452:165-72. [PMID: 22459046 DOI: 10.1016/j.brainres.2012.03.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 03/01/2012] [Accepted: 03/01/2012] [Indexed: 11/16/2022]
Abstract
The currently accepted scheme for reactive oxygen species production during ischemia/reperfusion injury is characterized by a deleterious mitochondria-derived burst of radical generation during reperfusion; however, recent examination of the penumbra suggests a central role for NADPH-oxidase (Nox)-mediated radical generation during the ischemic period. Therefore, we utilized a novel in vitro model of the penumbra to examine the free radical profile of ischemic murine hippocampal neurons using electron paramagnetic resonance spectroscopy, and also the role of Nox in this generation and in cell fate. We report that free radical production increased ~75% at 2 h of ischemia, and this increase was abolished by: (1) scavenging of extracellular free radicals with superoxide dismutase (SOD), (2) a general anion channel antagonist, or (3) the Nox inhibitor apocynin. Similarly, at 24 h of ischemia, [ATP] decreased >95% and vital dye uptake increased 6-fold relative to controls; whereas apocynin, the Cl(-) channel antagonist 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB), or the free radical scavenger N-acetyl cysteine (NAC) each provided moderate neuroprotection, ameliorating 13-32% of [ATP]-depletion and 19-56% of vital dye uptake at 24 h. Our results support a cytotoxic role for Nox-mediated free radical production from penumbral neurons during the ischemic period.
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Affiliation(s)
- Matthew E Pamenter
- Department of Pediatrics, Division of Respiratory Medicine, University of California San Diego, La Jolla, CA 92093, USA.
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41
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Ćavar S, Kovač F. Oxidative transformations of 4-methylcoumarins using dimethyldioxirane. J Heterocycl Chem 2011. [DOI: 10.1002/jhet.826] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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42
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Rana S, Chawla R, Kumar R, Singh S, Zheleva A, Dimitrova Y, Gadjeva V, Arora R, Sultana S, Sharma RK. Electron paramagnetic resonance spectroscopy in radiation research: Current status and perspectives. J Pharm Bioallied Sci 2011; 2:80-7. [PMID: 21814437 PMCID: PMC3147108 DOI: 10.4103/0975-7406.67006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 04/29/2010] [Accepted: 05/21/2010] [Indexed: 12/21/2022] Open
Abstract
Exposure to radiation leads to a number of health-related malfunctions. Ionizing radiation is more harmful than non-ionizing radiation, as it causes both direct and indirect effects. Irradiation with ionizing radiation results in free radical-induced oxidative stress. Free radical-mediated oxidative stress has been implicated in a plethora of diseased states, including cancer, arthritis, aging, Parkinson's disease, and so on. Electron Paramagnetic Resonance (EPR) spectroscopy has various applications to measure free radicals, in radiation research. Free radicals disintegrate immediately in aqueous environment. Free radicals can be detected indirectly by the EPR spin trapping technique in which these forms stabilize the radical adduct and produce characteristic EPR spectra for specific radicals. Ionizing radiation-induced free radicals in calcified tissues, for example, teeth, bone, and fingernail, can be detected directly by EPR spectroscopy, due to their extended stability. Various applications of EPR in radiation research studies are discussed in this review.
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Affiliation(s)
- Sudha Rana
- Division of CBRN Defence, Institute of Nuclear Medicine and Allied Sciences, Brig. S. K. Mazumdar Marg, Timarpur Delhi - 110054, India
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Patel A, Rohr-Udilova N, Rosenau T, Stolze K. Synthesis and characterization of 5-alkoxycarbonyl-4-hydroxymethyl-5-alkyl-pyrroline N-oxide derivatives. Bioorg Med Chem 2011; 19:7643-52. [PMID: 22094277 DOI: 10.1016/j.bmc.2011.10.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2011] [Revised: 09/12/2011] [Accepted: 10/07/2011] [Indexed: 10/16/2022]
Abstract
The syntheses, analytical properties, and spin trapping behavior of four novel EMPO derivatives, namely 5-ethoxycarbonyl-4-hydroxymethyl-5-methyl-pyrroline N-oxide (EHMPO), 5-ethoxycarbonyl-5-ethyl-4-hydroxymethyl-pyrroline N-oxide (EEHPO), 4-hydroxymethyl-5-methyl-5-propoxycarbonyl-pyrroline N-oxide (HMPPO), and 4-hydroxymethyl-5-methyl-5-iso-propoxycarbonyl-pyrroline N-oxide (HMiPPO), towards different oxygen- and carbon-centered radicals are described.
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Affiliation(s)
- Anjan Patel
- Department of Chemistry, University of Natural Resources and Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna, Austria
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44
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Spasojević I. Free radicals and antioxidants at a glance using EPR spectroscopy. Crit Rev Clin Lab Sci 2011; 48:114-42. [DOI: 10.3109/10408363.2011.591772] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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45
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Kao D, Chaintreau A, Lepoittevin JP, Giménez-Arnau E. Synthesis of allylic hydroperoxides and EPR spin-trapping studies on the formation of radicals in iron systems as potential initiators of the sensitizing pathway. J Org Chem 2011; 76:6188-200. [PMID: 21648947 DOI: 10.1021/jo200948x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Many terpenes used as fragrance compounds autoxidize when exposed to air, forming allylic hydroperoxides that have the potential to be skin contact allergens. To trigger the immunotoxicity process that characterizes contact allergy, these hydroperoxides are supposed to bind covalently to proteins in the skin via radical pathways. We investigated the formation of reactive radical intermediates from 7-hydroperoxy-3,7-dimethylocta-1,5-dien-3-ol and 2-hydroperoxylimonene, responsible for the sensitizing potential acquired by autoxidized linalool and limonene. Both compounds were synthesized through new short and reproducible synthetic pathways. The hydroperoxide decomposition catalyzed by Fe(II)/Fe(III) redox systems, playing a key role in degradating peroxides in vivo, was examined by spin-trapping-EPR spectroscopy. Alkoxyl and carbon-centered free radicals derived from the hydroperoxides were successfully trapped by the spin-trap 5,5-dimethyl-1-pyrroline N-oxide, whereas peroxyl radicals were characterized by spin-trapping studies with 5-diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide. Using liquid chromatography combined with mass spectrometry, we demonstrated the formation of adducts, via radical mechanisms induced by Fe(II)/Fe(III), between the hydroperoxides and N-acetylhistidine methyl ester, a model amino acid that is prone to radical reactions. Free radicals derived from these hydroperoxides can thus induce amino acid chemical modifications via radical mechanisms. The study of these mechanisms will help to understand the sensitizing potential of hydroperoxides.
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Affiliation(s)
- Dany Kao
- Laboratoire de Dermatochimie, Institut de Chimie de Strasbourg (UMR 7177), Université de Strasbourg, 4 Rue Blaise Pascal, 67081 Strasbourg, France
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Gosset G, Clément JL, Culcasi M, Rockenbauer A, Pietri S. CyDEPMPOs: A class of stable cyclic DEPMPO derivatives with improved properties as mechanistic markers of stereoselective hydroxyl radical adduct formation in biological systems. Bioorg Med Chem 2011; 19:2218-30. [DOI: 10.1016/j.bmc.2011.02.040] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 02/14/2011] [Accepted: 02/18/2011] [Indexed: 11/28/2022]
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47
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Dodd NJF, Jha AN. Photoexcitation of Aqueous Suspensions of Titanium Dioxide Nanoparticles: An Electron Spin Resonance Spin Trapping Study of Potentially Oxidative Reactions. Photochem Photobiol 2011; 87:632-40. [DOI: 10.1111/j.1751-1097.2011.00897.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Stolze K, Rohr-Udilova N, Patel A, Rosenau T. Synthesis and characterization of 5-hydroxymethyl-5-methyl-pyrroline N-oxide and its derivatives. Bioorg Med Chem 2011; 19:985-93. [PMID: 21211983 DOI: 10.1016/j.bmc.2010.11.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Revised: 11/17/2010] [Accepted: 11/20/2010] [Indexed: 11/24/2022]
Abstract
Synthesis and spin trapping behavior of three novel DMPO derivatives, namely 5-hydroxymethyl-5-methyl-pyrroline N-oxide (HMMPO), 5-(2-furanyl)-oxymethyl-5-methyl-pyrroline N-oxide (FMMPO), and 5-(2-pyranyl)-oxymethyl-5-methyl-pyrroline N-oxide (PMMPO) towards different oxygen- and carbon-centered radicals are described. The stabilizing effect of a series of cyclodextrins on the superoxide adducts was tested.
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Affiliation(s)
- Klaus Stolze
- Department of Biomedical Sciences, University of Veterinary Medicine Vienna, Austria.
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Maury J, Feray L, Bazin S, Clément JL, Marque SRA, Siri D, Bertrand MP. Spin-Trapping Evidence for the Formation of Alkyl, Alkoxyl, and Alkylperoxyl Radicals in the Reactions of Dialkylzincs with Oxygen. Chemistry 2011; 17:1586-95. [DOI: 10.1002/chem.201002616] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Indexed: 11/09/2022]
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Karoui H, Chalier F, Finet JP, Tordo P. DEPMPO: an efficient tool for the coupled ESR-spin trapping of alkylperoxyl radicals in water. Org Biomol Chem 2011; 9:2473-80. [DOI: 10.1039/c0ob00876a] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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