Photosensitization by hematoporphyrin: ESR evidence for free radical induction in unsaturated fatty acids and for singlet oxygen production

Cannistraro, Salvatore; Vorst, A. Van de

doi:10.1016/0006-291x(77)91642-4

Cited by 59 publications

(5 citation statements)

References 24 publications

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“…3 arose via authentic Type I photochemistry mediated by sensitizer radicals (26). With one possible exception (27), no rigorously established examples of Type I lipid photooxidation in membranes have been reported in the literature, whereas many examples of Type I1 photooxidation have been described (26). On this basis, it seems more likely that the 7aP-00H we observed arose indirectly, e.g.…”

Section: Photogeneration Of Chooh Speciesmentioning

confidence: 79%

Singlet Oxygen Adducts of Cholesterol: Photogeneration and Reductive Turnover in Membrane Systems

Korytowski

Girotti

1999

Photochem & Photobiology

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Identification of signature products provides a powerful means for establishing whether singlet molecular oxygen (1O2) is a reactive intermediate in a photodynamic process. This approach is particularly attractive for biological systems in which direct physical measurement is difficult because of the short lifetime of 1O2. Among the many possible reporter molecules in a target system, cholesterol (Ch) has the advantage of affording a limited number of readily distinguishable oxidation products, among which are the hydroperoxides 3 beta-hydroxy-5 alpha-cholest-6-ene-5-hydroperoxide (5 alpha-OOH), 3 beta-hydroxycholest-4-ene-6 alpha-hydroperoxide (6 alpha-OOH) and 3 beta-hydroxycholest-4-ene-6 beta-hydroperoxide (6 beta-OOH) that derive specifically from 1O2 addition. The purpose of this study was to compare these species in terms of (1) rates of accumulation in photodynamically treated liposomal membranes; (2) susceptibility to iron-mediated 1 e- reduction that triggers chain peroxidative damage; (3) susceptibility to selenoperoxidase (phospholipid hydroperoxide glutathione peroxidase [PHGPX])-mediated 2 e- reduction that protects against such damage and (4) relative toxicity to mammalian cells. Our results indicate that 5 alpha-OOH is photogenerated at a much greater initial rate than 6 alpha-OOH or 6 beta-OOH. Although liposomal 5 alpha-OOH, 6 alpha-OOH, and 6 beta-OOH exhibit similar first-order decay kinetics during iron/ascorbate treatment, the former decays much more slowly during GSH/PHGPX treatment, and is more toxic to L1210 cells. These and related findings suggest that 5 alpha-OOH is potentially the most damaging ChOOH to arise in photodynamically treated cells.

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Section: Photogeneration Of Chooh Speciesmentioning

confidence: 79%

Singlet Oxygen Adducts of Cholesterol: Photogeneration and Reductive Turnover in Membrane Systems

Korytowski

Girotti

1999

Photochem & Photobiology

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“…Cytotoxicity has been attributed to singlet oxygen [11][12][13], an excited state of molecular oxygen, and to the hydroxyl radical [13,14]. In vitro studies have demonstrated that hematoporphyrin produces both free radicals [15][16][17][18][19] and singlet oxygen [12,17].…”

Section: Introductionmentioning

confidence: 99%

Superoxide, hydrogen peroxide and singlet oxygen in hematoporphyrin derivative-cysteine, -NADH and -light systems

Buettner

Hall

1987

Biochimica et Biophysica Acta (BBA) - General Subjects

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Hematoporphyrin derivative and light in the presence of cysteine or glutathione were found to convert oxygen to superoxide and hydrogen peroxide at pH < approx. 6.5, while at pH > 6.5 no superoxide or hydrogen peroxide production was observed. However, at pH values greater than 6.5 the rate of oxygen consumption increased. This rate paralleled the acid dissociation curve of the cysteine thioi group and is consistent with the chemical quenching of tO z by cysteine. The superoxide and hydrogen peroxide formation observed below pH 6.5 appeared not to be related to the singlet oxygen production of hematoporphyrin derivative. In addition, superoxide and hydrogen peroxide production was observed with hematoporphyrin derivative and light in the presence of NADH, both above and below pH 6.5. Direct detection of singlet oxygen luminescence at 1268 nm in the hematoporphyrin derivative-light system (2HzO as solvent) revealed an apparent linear increase in the singlet oxygen emission intensity as the pZH was raised from 7.0 to 10.0. Azide efficiently quenched this observed emission. In addition, at p2H 7.4, 1 mM cysteine resulted in a 40% reduction of the singlet oxygen luminescence, while at pZH 9.4 the signal was quenched by over 95% (under the experimental conditions employed). In total, we interpret these results as consistent with the chemical quenching of to z by the ionized thiol group of cysteine.

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“…The activated molecules oxygenate cholesterol and possibly phospholipids and protein molecules (Cannistraro and Van de Vorst, 1977). On the other hand, irrespective of illumination, porphyrin binds irreversibly to spectrin, exposing living blood cells to lysis (Beaven and Gratzer, 1978).…”

Section: Discussionmentioning

confidence: 99%

“…These effects may result directly from the formation of singlet oxygen (Weishaupt et al, 1976) and hydroxyl radicals (Buettner and Oberley , 1979) which, in turn, react with membranous structures (Dubbelman et al, 1980). The activated molecules oxygenate cholesterol and possibly phospholipids and protein molecules (Cannistraro and Van de Vorst, 1977). On the other hand, irrespective of illumination, porphyrin binds irreversibly to spectrin, exposing living blood cells to lysis (Beaven and Gratzer, 1978).…”

Section: Discussionmentioning

confidence: 99%

Destruction of erythroleukemia, myelocytic leukemia and burkitt lymphoma cells by photoactivated protoporphyrin

Malik

Djaldetti

1980

Intl Journal of Cancer

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The effect of protoporphyrin on erythroid, myeloid and lymphoid leukemic cells and their destruction induced by the photoactivated porphyrin was studied. Friend erythroleukemic cells (FL) and myelocytic leukemic cells (ML) accumulated protoporphyrin in a cap or patch-like pattern observed by fluorescence microscopy. Photoactivated protoporphyrin induced the appearance of "holes" on the cell membrane demonstrated by scanning electron microscopy. On the other hand, Burkitt lymphoma (BL) and mastocytoma (MS) cells accumulated porphyrin intracellularly around the nuclear envelope and as circular profiles, respectively. Photoactivated protoporphyrin induced development of multiple blebs on the cell membrane, and even complete cell destruction. Cytotoxicity of protoporphyrin at short-term incubation periods was determined by [3H]thymidine and [3H]uridine incorporation. Protoporphyrin, unexposed to light, reduced the incorporation of both precursors only to a moderate extent. On the other hand, porphyrin-treated cells exposed to light showed complete inhibition of RNA and DNA synthesis. Long-term exposure of ML and BL cells to porphyrin in the dark induced a nearly 50% inhibition of RNA and DNA synthesis. Although the cytotoxic effect of protoporphyrin in the dark was lower than that of photoactivated porphyrin, this may possess a potential activity in vivo even without illumination.

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Photosensitization by hematoporphyrin: ESR evidence for free radical induction in unsaturated fatty acids and for singlet oxygen production

Cited by 59 publications

References 24 publications

Singlet Oxygen Adducts of Cholesterol: Photogeneration and Reductive Turnover in Membrane Systems

Singlet Oxygen Adducts of Cholesterol: Photogeneration and Reductive Turnover in Membrane Systems

Superoxide, hydrogen peroxide and singlet oxygen in hematoporphyrin derivative-cysteine, -NADH and -light systems

Destruction of erythroleukemia, myelocytic leukemia and burkitt lymphoma cells by photoactivated protoporphyrin

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