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Rizzi V, Fini P, Semeraro P, Cosma P. Detailed investigation of ROS arisen from chlorophyll a/Chitosan based-biofilm. Colloids Surf B Biointerfaces 2016; 142:239-247. [PMID: 26966998 DOI: 10.1016/j.colsurfb.2016.02.062] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 02/25/2016] [Accepted: 02/28/2016] [Indexed: 01/28/2023]
Abstract
The aim of this work is to study the nature of reactive oxygen species, ROS, arisen from Chitosan/2-HP-β-Cyclodextrin/Chlorophyll a (CH/CD/Chla) blended biofilm under a photodynamic activity. Suitable molecules, called primary acceptors, able to react selectively with ROS, in turn generated by the photosensitizer (PS), herein Chla, are used to attempt this purpose. The changes of the absorption and the emission spectra of these acceptors after the irradiation of aqueous solution containing the active biofilm have provided the specific nature of ROS and thus the main pathway of reaction followed by PS, in our condition. The (1)O2 formation was unveiled using Uric Acid (UA) and 9,10-diphenilanthracene (DPA). On the other hand, 2,7- dichlorofluorescin and Ferricytochrome c (Cyt-c) were used to detect the formation of hydrogen peroxide and superoxide radical anion, respectively. Results suggest that among the possible pathways of reaction, namely Type I and Type II, potentially followed by PSs, in our condition the hybrid biofilm CH/CD/Chla follows mainly Type II mechanism with the formation of (1)O2. However, the latter is involved in subsequent pathway of reaction involving Chla inducing, in addition, the formation of O2(-) and H2O2.
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Affiliation(s)
- Vito Rizzi
- Università degli Studi "Aldo Moro" di Bari, Dip. Chimica, Via Orabona, 4, 70126 Bari, Italy
| | - Paola Fini
- Consiglio Nazionale delle Ricerche CNR-IPCF, UOS Bari, Via Orabona, 4, 70126 Bari, Italy
| | - Paola Semeraro
- Università degli Studi "Aldo Moro" di Bari, Dip. Chimica, Via Orabona, 4, 70126 Bari, Italy
| | - Pinalysa Cosma
- Università degli Studi "Aldo Moro" di Bari, Dip. Chimica, Via Orabona, 4, 70126 Bari, Italy; Consiglio Nazionale delle Ricerche CNR-IPCF, UOS Bari, Via Orabona, 4, 70126 Bari, Italy.
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2
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Benković ET, Kreft S. Fagopyrins and Protofagopyrins: Detection, Analysis, and Potential Phototoxicity in Buckwheat. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:5715-5724. [PMID: 26024291 DOI: 10.1021/acs.jafc.5b01163] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Buckwheat contains many healthy nutrients, and its consumption is therefore increasing. Buckwheat also contains fluorescent phototoxic fagopyrins. A systematic review of fagopyrins and the phototoxicity of buckwheat found that reliable quantitative data on fagopyrin toxicity are not yet available. Generally, buckwheat seeds, flour, and teas are safe in normal amounts. Diets extensively composed of buckwheat sprouts, herbs, and particularly flowers or of fagopyrin-rich buckwheat extracts may cause fagopyrism. A reference standard is needed, as it would enable the accurate evaluation of fagopyrin content in buckwheat products and would allow proper testing of their as yet unknown physical, chemical, and biological characteristics.
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Affiliation(s)
- Eva Tavčar Benković
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia
| | - Samo Kreft
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia
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3
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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: 15] [Impact Index Per Article: 1.5] [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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Nafee N, Youssef A, El-Gowelli H, Asem H, Kandil S. Antibiotic-free nanotherapeutics: Hypericin nanoparticles thereof for improved in vitro and in vivo antimicrobial photodynamic therapy and wound healing. Int J Pharm 2013; 454:249-58. [DOI: 10.1016/j.ijpharm.2013.06.067] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Revised: 06/20/2013] [Accepted: 06/27/2013] [Indexed: 10/26/2022]
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Strejčková A, Staničová J, Jancura D, Miškovský P, Bánó G. Spatial Orientation and Electric-Field-Driven Transport of Hypericin Inside of Bilayer Lipid Membranes. J Phys Chem B 2013; 117:1280-6. [DOI: 10.1021/jp3114539] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alena Strejčková
- Department of Biophysics, Pavol Jozef Šafárik University, Jesenná
5, Košice 041 54, Slovak Republic
| | - Jana Staničová
- Institute of Biophysics and
Biomathematics, University of Veterinary Medicine, Komenského 73, Košice 041 81, Slovak Republic
| | - Daniel Jancura
- Department of Biophysics, Pavol Jozef Šafárik University, Jesenná
5, Košice 041 54, Slovak Republic
| | - Pavol Miškovský
- Department of Biophysics, Pavol Jozef Šafárik University, Jesenná
5, Košice 041 54, Slovak Republic
| | - Gregor Bánó
- Department of Biophysics, Pavol Jozef Šafárik University, Jesenná
5, Košice 041 54, Slovak Republic
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6
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Cellamare BM, Fini P, Agostiano A, Sortino S, Cosma P. Identification of Ros Produced by Photodynamic Activity of Chlorophyll/Cyclodextrin Inclusion Complexes. Photochem Photobiol 2012; 89:432-41. [DOI: 10.1111/j.1751-1097.2012.01238.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 09/07/2012] [Indexed: 01/03/2023]
Affiliation(s)
- Barbara M. Cellamare
- Dipartimento di Chimica; Università degli Studi “Aldo Moro” di Bari; Bari; Italy
| | | | | | - Salvatore Sortino
- Laboratory of Photochemistry; Department of Drug Sciences; University of Catania; Catania; Italy
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Gbur P, Dedic R, Chorvat Jr D, Miskovsky P, Hala J, Jancura D. Time-resolved Luminescence and Singlet Oxygen Formation After Illumination of the Hypericin-Low-density Lipoprotein Complex. Photochem Photobiol 2009; 85:816-23. [DOI: 10.1111/j.1751-1097.2008.00483.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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8
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Rahimipour S, Palivan C, Freeman D, Barbosa F, Fridkin M, Weiner L, Mazur Y, Gescheidt G. Hypericin Derivatives: Substituent Effects on Radical-anion Formation. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2001)0740149hdseor2.0.co2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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Webb SP. Ab initio electronic structure theory as an aid to understanding excited state hydrogen transfer in moderate to large systems. Theor Chem Acc 2005. [DOI: 10.1007/s00214-005-0011-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Kascakova S, Refregiers M, Jancura D, Sureau F, Maurizot JC, Miskovsky P. Fluorescence Spectroscopic Study of Hypericin-photosensitized Oxidation of Low-density Lipoproteins. Photochem Photobiol 2005; 81:1395-403. [PMID: 15960595 DOI: 10.1562/2005-04-28-ra-503] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
By means of UV-VIS absorption and fluorescence spectroscopy, we demonstrate that the photosensitizer hypericin (Hyp) interacts nonspecifically with low-density lipoproteins (LDL), most probably with the lipid fraction of LDL. The molar ratio of monomeric Hyp binding to nonoxidized LDL and mildly oxidized LDL is 30:1. Increasing the Hyp concentration further leads to the formation of Hyp aggregates inside the LDL molecule. We also demonstrate that photoactivated Hyp oxidizes LDL in a light dose and excitation wavelength dependent manner. The level of oxidation of LDL depends on the amount of Hyp inside the LDL molecule. The maximum of the photosensitized oxidation of the LDL by Hyp is achieved for a 30:1 molar ratio, which corresponds to the maximum concentration of monomeric form of Hyp in LDL.
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Affiliation(s)
- Slavka Kascakova
- Department of Biophysics, University of P. J. Safarik, Kosice, Slovak Republic
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11
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Reactivity of the photo excited forms of Hypericin, Hypocrellin A, Hypocrellin B and methylated Hypericin towards molecular oxygen. J Photochem Photobiol A Chem 2004. [DOI: 10.1016/s1010-6030(03)00343-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Ma JH, Zhao JQ, Jiang LJ. Photosensitization mechanism of active species by the complex of hypocrellin B with aluminum ion. Free Radic Res 2001; 35:607-17. [PMID: 11767418 DOI: 10.1080/10715760100301611] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
To improve the water solubility and red absorption of the parent hypocrellin B (HB), the complex of HB with aluminum ion has been first synthesized in high yield. The photodynamic action of Al(3+)-HB, especially the generation mechanism of active species, ([Al(3+)-HB].-, O2.- and 1O2) was studied using electron paramagnetic resonance (EPR) and spectrophotometric methods. In the deoxygenated DMSO solution of Al(3+)-HB, the semiquinone anion radical of Al(3+)-HB is photogenerated via the self-electron transfer between the excited and ground state species. The presence of electron donor significantly promotes the reduction of Al(3+)-HB. When oxygen is present, superoxide anion radical (O2.-) is formed via the electron transfer from [Al(3+)-HB].- to the ground state molecular oxygen. Singlet oxygen (1O2) can be produced via the energy transfer from triplet Al(3+)-HB to ground state oxygen molecules. Furthermore, it is very significant that the accumulation of [Al(3+)-HB].- would replace that of O2.- or 1O2 with the consumption of oxygen in the sealed system.
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Affiliation(s)
- J H Ma
- Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100080, China
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Rahimipour S, Palivan C, Freeman D, Barbosa F, Fridkin M, Weiner L, Mazur Y, Gescheidt G. Hypericin derivatives: substituent effects on radical-anion formation. Photochem Photobiol 2001; 74:149-56. [PMID: 11547548 DOI: 10.1562/0031-8655(2001)074<0149:hdseor>2.0.co;2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The electron-transfer properties of the hypericin derivatives, dibromo-, hexaacetyl-, hexamethyl- and desmethylhypericin, were studied. Cyclovoltammetric measurements revealed that dibromo- and desmethylhypericin have almost the same redox potentials as the parent hypericin. Substitution of the hydroxyl groups by acetoxy leads to less negative E1/2 values, whereas methoxy substitution induces more negative values. Electron paramagnetic resonance (EPR)/electron nuclear double resonance/general TRIPLE spectroscopy and quantum mechanical calculations were used to establish the structure of the one-electron reduced stages of hypericin derivatives. Proton loss in the bay region, already demonstrated for hypericin, was also found for dibromo- and desmethylhypericin. The spin and charge of the radical ions are predominately confined to the central biphenoquinone moiety of the hypericin skeleton. Generation of the radical ions by in situ electrolysis indicates that the redox potentials of hypericin, dibromo- and desmethylhypericin, containing hydroxyls at the 1, 3, 4, 6, 8 and 13 positions, largely depend on the solvent. With phosphate-buffered saline (pH 7.4)/dimethylsulfoxide (DMSO) as the solvent the EPR spectra of the corresponding radical ions appear at markedly lower potentials than in pure DMSO and N,N'-dimethylformamide. However, this effect is not observable for hexaacetyl- and hexamethyl-hypericin-lacking hydroxyl groups. In all cases the EPR data and calculations revealed the presence of 7,14 tautomers.
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Affiliation(s)
- S Rahimipour
- Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel
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Chaloupka R, Petit PX, Israël N, Sureau F. Over-expression of Bcl-2 does not protect cells from hypericin photo-induced mitochondrial membrane depolarization, but delays subsequent events in the apoptotic pathway. FEBS Lett 1999; 462:295-301. [PMID: 10622714 DOI: 10.1016/s0014-5793(99)01538-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Hypericin (HY) is a powerful photo-inducer of apoptosis in Jurkat cells as measured by caspase-3 activation, cell shrinkage, phosphatidylserine (PS) exposure and the appearance of hypoploid DNA. These processes are preceded by rapid Bcl-2-independent mitochondrial transmembrane depolarization and a drop in cytoplasmic pH. Pre-incubation of cells with inhibitors of the mitochondrial permeability transition pore, such as cyclosporin A or bongkrekic acid, does not protect cells from mitochondrial membrane potential (deltapsim) decrease. However, monitoring of mitochondrial entrapped calcein by confocal fluorescence imaging gives clear evidence of HY photo-induced mitochondrial permeability. This should be considered as the result of a non-specific alteration of mitochondrial membrane integrity brought about by lipid peroxidation. Nevertheless, synthesis of the anti-apoptotic protein Bcl-2 appears to delay the subsequent time course of PS exposure and to reduce caspase-3 activation and the fraction of cells which become hypoploid. We interpret this partially protective effect as the consequence of a direct interaction of Bcl-2 with cytosolic cytochrome c previously released from mitochondria upon deltapsim decrease and/or of Bcl-2 inhibition of the deleterious retro-effect of caspase-3 on the mitochondrial permeability transition pore and/or the mitochondrial membrane components.
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Affiliation(s)
- R Chaloupka
- Laboratoire de Physicochimie Biomoléculaire et Cellulaire (CNRS ESA 7033), Université P. et M. Curie, Paris, France
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16
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Yuying H, Jingyi A, Lijin J. Glycoconjugated hypocrellin: photosensitized generation of free radicals (O2*-, *OH, and GHB*-) and singlet oxygen (1O2). Free Radic Biol Med 1999; 27:203-12. [PMID: 10443937 DOI: 10.1016/s0891-5849(99)00076-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To improve water solubility and specific affinity for malignant tumors, glycoconjugated hypocrellin B (GHB) has been synthesized. Illumination of deoxygenated DMSO solution containing GHB generates a strong electron paramagnetic resonance (EPR) signal. The EPR signal is assigned to the semiquinone anion radical of GHB (GHB*-) based on a series of experimental results. Spectrophotometric measurements show that the absorption bands at 645 nm and 502 nm (pH 8.0) or 505 nm (pH 11.0) arise from the semiquinone anion radical (GHB*-) and hydroquinone (GHBH2) of GHB, respectively. GHBH2 is readily formed via the decay of GHB*- in water-contained solution. The increase of pH value of the reaction media promotes this process. When oxygen is present, superoxide anion radical (O2*-) is formed, via the electron transfer from GHB*-, the precursor, to ground state molecular oxygen. Hydroxyl radical can be readily detected by DMPO spin trapping when aerobic aqueous solution containing GHB is irradiated. As compared with the parent compound, hypocrellin B (HB), the efficiency of O2* and *OH generation by GHB photosensitization is enhanced significantly. Singlet oxygen (1O2) can be produced via the energy transfer from triplet GHB to ground state oxygen molecules, with a decreased quantum yield, i.e., 0.19. These findings suggest that the new GHB possesses an enhanced type I process and a decreased type II process as compared with hypocrellin B.
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Affiliation(s)
- H Yuying
- Institute of Photographic Chemistry, Academia Sinica, Beijing, People's Republic of China
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17
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Abstract
Antioxidant enzyme activities were measured following exposure to hypericin +/- irradiation in EMT6 cells. CuZnSOD and catalase activities peaked within 0.5 h following irradiation for nontoxic 0.5 microM hypericin and toxic 1.0 microM hypericin. Catalase remained elevated up to 3 h for 1.0 microM hypericin + light. MnSOD activity was elevated immediately following irradiation for both doses. These levels returned to control by 1 h for 0.5 microM hypericin, but were depressed after 1 h for 1.0 microM hypericin. This suggests that mitochondria impairment may be a critical factor in hypericin phototoxicity. Glutathione reductase was inhibited immediately following irradiation with 1.0 microM hypericin, suggesting that an altered status of the glutathione pool contributed to cytotoxicity. Glutathione peroxidase activities were elevated following irradiation but returned to control levels within 0.5 h for both doses, implicating hydroperoxide formation as an early event in hypericin phototoxicity. Inhibition by hypericin in the dark was demonstrated for purified CuZnSOD, Se-dependent glutathione peroxidase, glutathione S-transferase, and glutathione reductase activities in vitro. Irradiation did not potentiate hypericin-mediated glutathione reductase inhibition and decrease inhibition for the other enzymes. Collectively, these data demonstrate an antioxidant enzyme response to hypericin photoactivation and confirm a role for oxygen in hypericin phototoxicity.
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Affiliation(s)
- S A Johnson
- Cancer Research Laboratory, Department of Biochemistry, University of Nevada, Reno 89557, USA
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18
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Hadjur C, Wagnieres G, Monnier P, Bergh H. EPR and Spectrophotometric Studies of Free Radicals (O2°−, °OH, BPD-MA°−) and Singlet Oxygen (1O2) Generated by Irradiation of Benzoporphyrin Derivative Monoacid Ring A. Photochem Photobiol 1997. [DOI: 10.1111/j.1751-1097.1997.tb01929.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Losi A. Fluorescence and Time-Resolved Photoacoustics of Hypericin Inserted in Liposomes: Dependence on Pigment Concentration and Bilayer Phase. Photochem Photobiol 1997. [DOI: 10.1111/j.1751-1097.1997.tb01926.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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20
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Hadjur C, Wagnières G, Ihringer F, Monnier P, van den Bergh H. Production of the free radicals O2.- and .OH by irradiation of the photosensitizer zinc(II) phthalocyanine. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 1997; 38:196-202. [PMID: 9203381 DOI: 10.1016/s1011-1344(96)07440-4] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Zinc(II) phthalocyanine (ZnPC) is a new photosensitizer currently undergoing phase I and II clinical trials at Lausanne's CHUV hospital for the photodynamic therapy (PDT) of early cancer in the upper aerodigestive tract. Activated oxygen species other than singlet oxygen produced during the photosensitization of ZnPC in liposomes have been examined by electron paramagnetic resonance (EPR) spin trapping and by the cytochrome c reduction method. Visible light irradiation of ZnPC associated with liposomes in the presence of the spin trap 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) gives an EPR spectrum characteristic of the DMPO-hydroperoxyl radical spin adduct (DMPO-.OOH). Superoxide anion attains a level of 1 microM min-1 20 min after the start of irradiation as determined by the superoxide dismutase (SOD)-inhibitable reduction of cytochrome c. The yield of O2.- is strongly enhanced by physiological electron donors. An EPR spectrum characteristic of the DMPO-hydroxyl radical spin adduct (DMPO-.OH) is also observed. The addition of dimethyl sulphoxide or ethanol produces additional hyperfine splittings due to the respective hydroxyalkyl radical products, indicating the presence of free .OH. DMPO-.OH is significantly inhibited by desferrioxamine or catalase. Conversely, this adduct is enhanced by hydrogen peroxide. These data demonstrate the ability of ZnPC in liposomes to photoreact effectively by an electron transfer mechanism. Such type I processes may add to the effects of singlet oxygen in ZnPC-mediated PDT.
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Affiliation(s)
- C Hadjur
- Institut du Génie de l'Environnement, Ecole Polytechnique Fédérale de Lausanne, DGR-LPAS, Lausanne, Switzerland.
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Wells TA, Losi A, Dai R, Scott P, Park SM, Golbeck J, Song PS. Electron Transfer Quenching and Photoinduced EPR of Hypericin and the Ciliate Photoreceptor Stentorin. J Phys Chem A 1997. [DOI: 10.1021/jp9612588] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Todd A. Wells
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Aba Losi
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Renke Dai
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Paul Scott
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Su-Moon Park
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - John Golbeck
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
| | - Pill-Soon Song
- Departments of Chemistry and Biochemistry, University of Nebraska, Lincoln, Nebraska 68588-0304
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22
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Hadjur C, Richard MJ, Parat MO, Jardon P, Favier A. Photodynamic effects of hypericin on lipid peroxidation and antioxidant status in melanoma cells. Photochem Photobiol 1996; 64:375-81. [PMID: 8760577 DOI: 10.1111/j.1751-1097.1996.tb02474.x] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Photodynamic-induced cytotoxicity by hypericin (HYP) was studied on three human melanoma cell lines: one pigmented cell line (G361) and two amelanotic cell lines (M18 and M6). No significant variation in the rate of uptake and in the maximum level of HYP incorporation for the different cells was observed. In the dark, no cytotoxicity was observed in the range 0-10-6 M HYP for the three cell lines. Amelanotic cells were found to be more sensitive than pigmented cells to irradiation of HYP with visible light (lambda > 590 nm). In addition, for the three cell lines HYP-induced photocytotoxicity was found to be drug-dose and light-dose dependent. Under the conditions used, thiobarbituric acid-reacting substances (TBARs) were significantly increased in amelanotic cells after irradiation (P < 0.0001). By contrast, the amount of TBARS remained unchanged in pigmented cells. Antioxidant defenses including enzymes and glutathione (GSH) were assayed before and after HYP photosensitization. Significantly increased total SOD activity was observed after photosensitizaton for amelanotic cells (P < 0.05), while glutathione peroxidase (GSHPx) and catalase (Cat) activities but also GSH levels were significantly decreased (P < 0.01). In pigmented cells a significantly increased Cat activity was found (P < 0.05), whereas GSHPx was unaffected after irradiation. It can be inferred that (a) HYP may be an effective PDT agent for melanoma and (b) there is a relationship between melanin content and sensitivity to HYP phototoxicity in human melanoma cells.
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Affiliation(s)
- C Hadjur
- laboratorie de Biochimie C, Centre Hospitalier Régional Universitaire A. Michallon, Grenoble, France.
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