901
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Cohet M. [ Singlet oxygen in endodontics]. ACTUALITES ODONTO-STOMATOLOGIQUES 1987; 41:159-63. [PMID: 3475962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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902
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Blan QA, Grossweiner LI. Singlet oxygen generation by furocoumarins: effect of DNA and liposomes. Photochem Photobiol 1987; 45:177-83. [PMID: 3562582 DOI: 10.1111/j.1751-1097.1987.tb05361.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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903
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Redmond RW, Heihoff K, Braslavsky SE, Truscott TG. Thermal-lensing and phosphorescence studies of the quantum yield and lifetime of singlet molecular oxygen (1 delta g) sensitized by hematoporphyrin and related porphyrins in deuterated and non-deuterated ethanols. Photochem Photobiol 1987; 45:209-13. [PMID: 3562584 DOI: 10.1111/j.1751-1097.1987.tb05365.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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904
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Gorman AA, Hamblett I, Rodgers MA. Ergosterol (provitamin D2) triplet state: an efficient sensitiser of singlet oxygen, O2(1 delta g), formation. Photochem Photobiol 1987; 45:215-21. [PMID: 3562585 DOI: 10.1111/j.1751-1097.1987.tb05366.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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905
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Wefers H, Schulte-Frohlinde D, Sies H. Loss of transforming activity of plasmid DNA (pBR322) in E. coli caused by singlet molecular oxygen. FEBS Lett 1987; 211:49-52. [PMID: 3026841 DOI: 10.1016/0014-5793(87)81272-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Plasmid DNA pBR322 in aqueous solution was exposed to singlet molecular oxygen (1O2) generated by microwave discharge. DNA damage was detected as loss of transforming activity of pBR322 in E. coli (CMK) dependent on the time of exposure. DNA damage was effectively decreased by singlet-oxygen quenchers such as sodium azide and methionine. Replacement of water in the incubation buffer by D2O led to an increase in DNA damage. 9,10-Bis(2-ethylene)anthracene disulfate was used as a chemical trap for 1O2 quantitation by HPLC analysis of the endoperoxide formed.
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906
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Egorov SI, Babizhaev MA, Krasnovskiĭ AA, Shvedova AA. [Photosensitized generation of singlet molecular oxygen by endogenous substances of the eye lens]. BIOFIZIKA 1987; 32:169-71. [PMID: 3814638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
It is shown that kinurenine derivatives, harmane (beta-carboline) and tetracycline hydrochloride known as photosensitizers of cataractogenesis in lens produce luminescence of singlet molecular oxygen (1O2) under photoexcitation in air saturated aqueous (D2O) solution. The quantum yields of the 1O2 generation by these substances are determined. The data obtained by this direct 1O2 determination technique suggest that 1O2 might take part in cataractogenesis.
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907
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Duchstein HJ. Oxygen activation and deactivation in the presence of simple metal-chelates. FREE RADICAL RESEARCH COMMUNICATIONS 1987; 4:61-7. [PMID: 2852621 DOI: 10.3109/10715768709088089] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Molecular oxygen is a paramagnetic molecule having a triplet ground state. In the presence of some metal-complexes, e.g. of cobalt, copper and iron this ground state is abolished, and oxygen is in an activated state. First of all the addition of molecular oxygen to a metal complex could involve a formal oxidation of the metal center and a concomitant reduction of the bound oxygen. The question is, whether this state of oxygen is the reactive species in oxygenation reactions. With some chemical and physicochemical experiments we would like to show evidence for the singlet character of such a bound oxygen in some cases. The reaction is the oxygenation of 1.5-dihydroxy-naphthalene (1) to give juglone (2) in the presence of Co-salen in high yield. This reaction is affected by specific singlet oxygen quenchers, such as DABCO, sodium azide and Ni(II)-chelates. By measuring the ultraweak chemiluminescence, these findings could be supported.
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908
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Gibson SL, Murant RS, Hilf R. Photosensitizing effects of hematoporphyrin derivative immobilized on sepharose. Photochem Photobiol 1987; 45:93-104. [PMID: 2951754 DOI: 10.1111/j.1751-1097.1987.tb08409.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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909
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Lee PC, Rodgers MA. Laser flash photokinetic studies of rose bengal sensitized photodynamic interactions of nucleotides and DNA. Photochem Photobiol 1987; 45:79-86. [PMID: 3031708 DOI: 10.1111/j.1751-1097.1987.tb08407.x] [Citation(s) in RCA: 229] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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910
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Krishna CM, Lion Y, Riesz P. A study of 1O2 production by immobilized sensitizer outside the solution. Measurement of 1O2 generation. Photochem Photobiol 1987; 45:1-6. [PMID: 3562573 DOI: 10.1111/j.1751-1097.1987.tb08398.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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911
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Thomas MJ, Shirley PS, Hedrick CC, DeChatelet LR. Role of free radical processes in stimulated human polymorphonuclear leukocytes. Biochemistry 1986; 25:8042-8. [PMID: 3026467 DOI: 10.1021/bi00372a037] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Human polymorphonuclear leukocytes produce large quantities of superoxide when they attack and kill bacteria. However, superoxide is a weak oxidizing and reducing agent, and other more reactive oxygen species derived from reactions of superoxide are suggested to participate in the killing processes. To test the hypothesis that a reactive free radical or singlet oxygen is involved in bactericidal activity, human polymorphonuclear leukocytes were exposed to phagocytozable particles containing lipids that contain the easily autoxidized 1,4-diene moiety. After incubation the preparations were extracted and the extracts reduced with NaBH4 to convert hydroperoxides to stable alcohols. Using gas chromatography/mass spectrometry to analyze the extracts, we were unable to detect products unless iron salts were added to the medium. The products obtained by extraction are those that would be expected if both free radical chain autoxidation and 1O2 oxidation were taking place. In summary, we find that polymorphonuclear leukocytes do not cause peroxidation, implying that formation of strongly oxidizing free radicals is not an intrinsic property of the leukocyte. Added iron catalyzes peroxidation by activated leukocytes yielding an unusual distribution of hydroxylated products.
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912
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Thompson A, Nigro J, Seliger HH. Efficient singlet oxygen inactivation of firefly luciferase. Biochem Biophys Res Commun 1986; 140:888-94. [PMID: 3778490 DOI: 10.1016/0006-291x(86)90718-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Firefly luciferase is inactivated by singlet oxygen at near diffusion controlled rates, 1.9 X 10(9) M-1 s-1, based on direct comparison with the oxidation of L-histidine. The inactivation kinetics are multiphasic. Inactivation is inhibitable by NaN3. Surface-separated-sensitizer (SSS) system in which singlet oxygen is produced above an air gap separating the reaction solution from the Rose Bengal sensitizer, ensuring only Type II reactions, was compared with a Sensitox II system in which the polymer bound Rose Bengal is contained in the reaction solution and both Type I and Type II reactions can occur. A slight stabilization is afforded by MgSO4.
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913
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Kanofsky JR. Singlet oxygen production by bleomycin. A comparison with heme-containing compounds. J Biol Chem 1986; 261:13546-50. [PMID: 2428818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Fe(III)-bleomycin catalyzes the decomposition of 13-hydroperoxylinoleic acid and of 15-hydroperoxyarachidonic acid to produce small quantities of singlet oxygen. No singlet oxygen is produced when hydrogen peroxide, ethyl hydroperoxide, cumene hydroperoxide, and t-butyl hydroperoxide are used as substrates. The heme-containing catalysts, methemoglobin and hematin, have identical hydroperoxide substrate requirements for singlet oxygen production. The hydroperoxide requirements for singlet oxygen production correlate with those reported by Dix et al. (Dix, T.A., Fontana, R., Panthani, A., and Marnett, L.J. (1985) J. Biol. Chem. 260, 5358-5365) for the production of peroxyl radicals in the hematin-catalyzed decomposition of hydroperoxides. The bimolecular reaction of peroxyl radicals is a plausible reaction mechanism for the singlet oxygen production in the systems studied.
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914
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Xiao XL, Li QY, Zhang MQ, Wang DY, Zhang LH. [A biogenetic synthesis of prostaglandin E1 methyl ester]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1986; 21:630-2. [PMID: 3811960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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915
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Rosenthal I, Murali Krishna C, Riesz P, Ben-Hur E. The role of molecular oxygen in the photodynamic effect of phthalocyanines. Radiat Res 1986; 107:136-42. [PMID: 3737875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Phthalocyanines are a class of mammalian cell photosensitizers which may be useful in photodynamic therapy for cancer. Chloroaluminum phthalocyanine tetrasulfonate was incubated with Chinese hamster cells in culture and exposed to white light at different concentrations of oxygen. The ability of the cells to form colonies served as an end point for the photobiological effect of the dye. The efficiency of photoinactivation of the sensitized cells decreased with decreasing oxygen concentration. Very little photoinactivation was observed when the atmosphere equilibrated with the cells was oxygen-free nitrogen. At an oxygen partial pressure of 2.5 mm Hg, photoinactivation was reduced by 50% compared to ambient atmosphere. In an attempt to understand the nature of the interaction between excited dyes and oxygen, the ability of several phthalocyanines to photogenerate singlet oxygen was measured. Thus phthalocyanines containing paramagnetic ions (copper, iron, vanadyl) do not generate 1O2 in contradistinction to diamagnetic metals (zinc and aluminum). The latter are efficient photosensitizers, while the former have little if any photobiological activity. In spite of this correlation, singlet oxygen may not be the intermediate involved in cytotoxicity. The reasons are discussed.
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916
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Cadet J, Berger M, Decarroz C, Wagner JR, van Lier JE, Ginot YM, Vigny P. Photosensitized reactions of nucleic acids. Biochimie 1986; 68:813-34. [PMID: 3092878 DOI: 10.1016/s0300-9084(86)80097-9] [Citation(s) in RCA: 156] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The main effects of near-ultraviolet and visible light on cellular DNA are reviewed with emphasis on base lesions, oligonucleotide single-strand breaks and DNA-protein cross-links. Model system photosensitization reactions of DNA are also discussed. This includes photodynamic effects, menadione-mediated photooxidation, photoionization of antibiotics, the photochemistry of 5-halogenopyrimidines and urocanic acid.
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917
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Kraljić I. Detection of singlet oxygen and its role in dye-sensitized photooxidation in aqueous and micellar solutions. Biochimie 1986; 68:807-11. [PMID: 3092877 DOI: 10.1016/s0300-9084(86)80096-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Indirect methods for the detection of singlet oxygen in dye-sensitized photooxidation based on its interception by some singlet oxygen acceptors in aqueous and micellar solutions are discussed. Mechanistic aspects and some applications of a very sensitive method using p-nitrosodimethylaniline in the presence of imidazole (RNO + imidazole method) are also treated. The technique of competition kinetics with a singlet oxygen quencher N-3 which can serve for the determination of the role of singlet oxygen is discussed as well. Such competition with tryptophan and guanosine shows that these substrates react exclusively or predominantly via the singlet oxygen mechanism in the presence of hematoporphyrin as sensitizing dye.
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918
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Abstract
The chemical mechanisms of the photosensitized peroxidation of unsaturated fatty acids and cholesterol are reviewed and the subsequent reactions of peroxide decomposition products with biological targets such as DNA and amino acids are analyzed. The importance of protein photooxidation and cross-linking in membrane function impairment is discussed.
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919
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920
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Abstract
8-Methoxypsoralen in combination with UVA radiation (PUVA) is carcinogenic in mice and probably so in man. PUVA is genotoxic and so has tumour initiation potential. Some evidence suggests that PUVA has other biological effects which may be equated with tumour promotion. Thus, the use of a two-stage model, similar to that of chemical carcinogenesis, may be a useful experimental approach for the further understanding of PUVA carcinogenesis.
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921
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Abstract
Because of the ability of photosensitizers to induce specific photochemical reactions in vivo, leading to cell injury and death, many such molecules have been considered as therapeutic agents. Among them two classes of sensitizers, i.e. furocoumarins (psoralens) and porphyrins, are currently used for the photochemotherapy of various skin diseases and malignant lesions. Different types of cell responses can result according to the intracellular localization of the photosensitizer and to the nature of the photochemistry induced by the chromophore which absorbs photons. In this review, the cytological aspects of photosensitization by psoralens and porphyrins will be discussed.
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922
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Abstract
This paper discusses the mechanism of photooxygenation reactions sensitized by dyes, such as: rose bengal, methylene blue, tetraphenylporphin and chlorophyll a. First it is shown more particularly that: the quantum yields of singlet oxygen O2(1 delta g) production gamma delta, and of intersystem crossing singlet S1-triplet T1, gamma is, are not always equal and that the possibilities gamma delta greater than or less than gamma is may occur or are observed; the processes S1 + O2(3 sigma)----T1 + O2(3 sigma) and T1 + O2(3 sigma)----S0 + O2(1 delta g) are mainly if not fully responsible for the quenching of the singlet and triplet excited states of the sensitizer by oxygen. Thereafter, clear indication is given of the considerable complication of the photooxygenation which may arise from particular properties of the investigated substrate A (or of other compounds present in the reaction medium) and which may result in a decrease of the oxygenation quantum yield phi O2. It is shown that this lowering of phi O2 is due to that of gamma delta and/or of phi A, (the probability that O2(1 delta g) yields an oxygenation product AO2) since phi O2 = gamma delta phi A. The latter effect can be induced by the quenching of singlet oxygen by the dye, a process which is quite general and which must be always taken into account in kinetic studies.
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923
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Piette J, Decuyper J, Merville-Louis MP, Van de Vorst A. Biomolecular photoalterations mediated by phenothiazine derivatives. Biochimie 1986; 68:835-42. [PMID: 3019433 DOI: 10.1016/s0300-9084(86)80098-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
This survey focuses on recent developments in the field of the ultraviolet photochemistry and photobiology of phenothiazine derivatives. One of the major alterations introduced by this kind of photosensitized reaction is a covalent addition of the photosensitizer or one of its photoproducts onto the macromolecular target. This reaction has been observed with soluble and membrane proteins, lipids and DNA. In the latter case, the addition occurs at the level of guanine residues and leads to inhibition of DNA replication.
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924
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Kawanishi S, Inoue S, Sano S. Mechanism of DNA cleavage induced by sodium chromate(VI) in the presence of hydrogen peroxide. J Biol Chem 1986; 261:5952-8. [PMID: 3009436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Reactivities of chromium compounds with DNA were investigated by the DNA sequencing technique using 32P 5'-end-labeled DNA fragments, and the reaction mechanism was investigated by ESR spectroscopy. Incubation of double-stranded DNA with sodium chromate(VI) plus hydrogen peroxide or potassium tetraperoxochromate(V) led to the cleavage at the position of every base, particularly of guanine. Even without piperidine, the formation of oligonucleotides was observed, suggesting the breakage of the deoxyribose-phosphate backbone. ESR studies using hydroxyl radical traps demonstrated that hydroxyl radical is generated both during the reaction of sodium chromate(VI) with hydrogen peroxide and the decomposition of potassium tetraperoxochromate(V), and that hydroxyl radical reacts significantly not only with mononucleotides but also with deoxyribose 5-phosphate. ESR studies using a singlet oxygen trap demonstrated that singlet oxygen is also generated both by the same reaction and decomposition, and reacts significantly with deoxyguanylate, but scarcely reacts with other mononucleotides. Furthermore, ESR studies suggested that tetraperoxochromate(V) is formed by the reaction of sodium chromate(VI) with hydrogen peroxide. These results indicate that sodium chromate(VI) reacts with hydrogen peroxide to form tetraperoxochromate(V), leading to the production of the hydroxyl radical, which causes every base alteration and deoxyribose-phosphate backbone breakage. In addition, sodium chromate(VI) plus hydrogen peroxide generates singlet oxygen, which subsequently oxidizes the guanine residue. The mechanism by which both hydroxyl radical and singlet oxygen are generated during the reaction of sodium chromate(VI) with hydrogen peroxide was presented. Finally, the possibility that this reaction may be one of the primary reactions of carcinogenesis induced by chromate(VI) is discussed.
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925
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Kawanishi S, Inoue S, Sano S, Aiba H. Photodynamic guanine modification by hematoporphyrin is specific for single-stranded DNA with singlet oxygen as a mediator. J Biol Chem 1986; 261:6090-5. [PMID: 3009444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Photodynamic modification of DNA by hematoporphyrin (Hp) was characterized by the DNA sequencing technique using 32P-labeled DNA fragments, and the reaction mechanism was investigated by ESR spectroscopy. Mild photodynamic treatment of single-stranded DNA with Hp induced an alteration of guanine residues, and subsequent treatment with piperidine led to chain cleavages at each guanine residue. On the other hand, methylene blue plus light modified the guanine residues in both single-stranded and double-stranded DNA. ESR studies using 2,2,6,6-tetramethylpiperidine and 2,2,6,6-tetramethyl-4-piperidone as singlet oxygen traps demonstrated that Hp plus light produced almost the same amount of singlet oxygen as methylene blue plus light and that the photochemically generated singlet oxygen reacts significantly with guanylate but only slightly with other mononucleotides. An ESR spin destruction method revealed that photoexcited Hp generated porphyrin radical, but guanylate did not react with this radical. These results indicate that photoexcited Hp reacts with oxygen to generate singlet oxygen which oxidizes the guanine residues of single-stranded DNA and that the difference in photoreactivities of DNA with Hp and methylene blue may be explained in terms of the structural difference in their intercalating abilities.
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