The role of singlet oxygen and triplet carbonyls in biological systems

Durán, Nélson; Cadenas, Enrique

doi:10.1007/bf03156138

Cited by 11 publications

(13 citation statements)

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“…Reactions leading to those light‐emitting compounds are dioxetane breakdown and self‐reactions between lipid peroxy and alkoxy radicals. Upon relaxation, excited carbonyls emit light in the blue wavelength region (350–480 nm) while bimolecular emission of 1 O 2 occurs in the red region (703–706 and 640 nm) (Duran and Cadenas, 1987). The spectral characteristics of the imaged chemiluminescence of oxidized lipids are compatible with the supposed contribution of excited carbonyls and 1 O 2 (Figure 7a).…”

Section: Resultsmentioning

confidence: 99%

“…It has an extremely low intensity, up to some hundred of photons per second, and is invisible to the naked eye. The mechanism of emission is believed to be the generation of metastable excited states resulting from oxidative metabolic reactions (Duran and Cadenas, 1987), which closely relates spontaneous photon emission to the oxidation status of the organism. Spontaneous chemiluminescence is distinct from the bioluminescence phenomena observed, for example, in fireflies and luminescent bacteria, jellyfish or fish.…”

Section: Introductionmentioning

confidence: 99%

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Using spontaneous photon emission to image lipid oxidation patterns in plant tissues

et al. 2011

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SUMMARYPlants, like almost all living organisms, spontaneously emit photons of visible light. We used a highly sensitive, low-noise cooled charge coupled device camera to image spontaneous photon emission (autoluminescence) of plants. Oxidative stress and wounding induced a long-lasting enhancement of plant autoluminescence, the origin of which is investigated here. This long-lived phenomenon can be distinguished from the short-lived chlorophyll luminescence resulting from charge recombinations within the photosystems by pre-adapting the plant to darkness for about 2 h. Lipids in solvent were found to emit a persistent luminescence after oxidation in vitro, which exhibited the same time and temperature dependence as plant autoluminescence. Other biological molecules, such as DNA or proteins, either did not produce measurable light upon oxidation or they did produce a chemiluminescence that decayed rapidly, which excludes their significant contribution to the in vivo light emission signal. Selective manipulation of the lipid oxidation levels in Arabidopsis mutants affected in lipid hydroperoxide metabolism revealed a causal link between leaf autoluminescence and lipid oxidation. Addition of chlorophyll to oxidized lipids enhanced light emission. Both oxidized lipids and plants predominantly emit light at wavelengths higher than 600 nm; the emission spectrum of plant autoluminescence was shifted towards even higher wavelengths, a phenomenon ascribable to chlorophyll molecules acting as luminescence enhancers in vivo. Taken together, the presented results show that spontaneous photon emission imaged in plants mainly emanates from oxidized lipids. Imaging of this signal thus provides a simple and sensitive non-invasive method to selectively visualize and map patterns of lipid oxidation in plants.

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Using spontaneous photon emission to image lipid oxidation patterns in plant tissues

et al. 2011

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“…Este último é, entre as espécies radicalares conhecidas, uma das mais reativas, pois necessita somente de mais um elétron para se estabilizar. Estas espécies reativas de oxigênio para se estabilizarem devem doar ou receber elétrons de uma ou outra molécu-la, tornando esta última uma espécie também radicalar e a conseqüência disto é a oxidação dos fosfolipídios de membranas celulares e subcelulares, do DNA, e das proteínas 49 . Portanto, a toxicidade do oxigênio, em praticamente todas as células aeróbias, decorre da formação de EROs que podem interagir com diversas biomoléculas, com o objetivo de se estabilizarem lesando diferentes estruturas celulares 49,50 .…”

Section: Radicais Livres E As Espécies Reativas De Oxigêniounclassified

“…Estas espécies reativas de oxigênio para se estabilizarem devem doar ou receber elétrons de uma ou outra molécu-la, tornando esta última uma espécie também radicalar e a conseqüência disto é a oxidação dos fosfolipídios de membranas celulares e subcelulares, do DNA, e das proteínas 49 . Portanto, a toxicidade do oxigênio, em praticamente todas as células aeróbias, decorre da formação de EROs que podem interagir com diversas biomoléculas, com o objetivo de se estabilizarem lesando diferentes estruturas celulares 49,50 . Em condições normais, a concentração destas espécies dentro das cé-lulas é extremamente baixa pelo fato de existirem enzimas antioxidantes que as removem, ou impedem sua formação.…”

Section: Radicais Livres E As Espécies Reativas De Oxigêniounclassified

Sistema antioxidante envolvendo o ciclo metabólico da glutationa associado a métodos eletroanalíticos na avaliação do estresse oxidativo

Júnior¹,

Höehr²,

Vellasco³

et al. 2001

Quím. Nova

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Recebido em 27/1/00; aceito em 12/5/00 ANTIOXIDANT SYSTEM INVOLVING THE GLUTATHIONE METABOLIC CYCLE ASSOCIATED TO ELECTROANALYTICAL METHODS IN THE OXIDATIVE STRESS EVALUATION. The most relevant advances on the analytical applications of glutathione determination based on glutathione redox cycle and the antioxidant system are given. The main enzymes that participate of the glutathione metabolism are the glutathione peroxidase and glutathione reductase. The glutathione peroxidase has a major role in the removal of hydrogen peroxide and lipid peroxides from the cells. These enzymes, operating in tandem with catalase and superoxide dismutase promote a scavenging of oxyradical products in tissues minimizing damages caused by these species. Reduced glutathione is the major intracellular thiol found in mammals and changes in the glutathione concentration in biological fluids or tissues may provide a useful marker in certain disorders like hemolytic anemia, myocardial oxidative stress and in the investigation of some kinds of cancers. Particular attention is devoted to the main advantages supplied by biosensors in which there is an incorporation of bioactive materials for the glutathione determination. The correlation between stability and sensitivity of some reduced glutathione electrochemical sensors is discussed.Keywords: glutathione; electroanalysis; bioelectrochemistry; oxidative stress. Divulgação Quim. Nova, Vol. 24, No. 1, 112-119, 2001. INTRODUÇÃOA incidência de doenças relacionadas a processos cancerígenos no organismo, envolvendo a formação de espéci-es reativas de oxigênio tais como peróxido de hidrogênio e o radical hidroxila, vem merecendo especial atenção nos últimos anos. Existe uma importante correlação entre os níveis de glutationa em sua forma reduzida e os mecanismos enzimáticos de defesa. Esta observação tem promovido uma série de estudos clínicos sobre a interdependência entre o aumento dos ní-veis de glutationa no plasma sangüíneo e doenças cancerígenas em determinados órgãos vitais como rins e pulmões 1,2 . Glutationa, um tripeptídeo (γ-L-glutamil-L-cisteinil-glicina), existe no organismo em suas formas reduzida (GSH) e oxidada (GSSG), atuando direta ou indiretamente em muitos processos biológicos importantes, incluindo a síntese de proteínas, metabolismo e proteção celular 3 . Em particular, problemas na sín-tese e metabolismo da glutationa estão associados a algumas doenças, nas quais os níveis de glutationa e das enzimas que atuam no seu metabolismo podem ser bastante significativos no diagnóstico de alguns tipos de câncer, bem como em outras doenças relacionadas ao estresse oxidativo 4-6 . Mudanças na concentração deste tripeptídeo podem ser um indicador útil em certas desordens fisiológicas como anemias causadas por infecção ou seguidas pela administração de algumas drogas oxidantes 7 , no monitoramento da eficácia de alguns tratamentos usando N-acetil-L-cisteína (NAC) durante o metabolismo do paracetamol 8 , no tratamento de pacientes com artrite reumatróide 9 e na investigação do estresse ...

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“…The oxidation of lipids, proteins, and nucleic acids by ROS is accompanied by the formation of electronically excited species such as triplet carbonyls 3 (C=O) * and singlet oxygen ( 1 O 2 ). 15,16 The light emission of the electronically excited species in the spectral range from 200 to 800 nm is known as weak chemiluminescence often called ultraweak photon emission. [17][18][19][20][21] Typically, the intensity of photon emission is less than approximately 10 − 15 W/cm 2 on the surface of human skin.…”

Section: Introductionmentioning

confidence: 99%

Spontaneous ultraweak photon emission imaging of oxidative metabolic processes in human skin: effect of molecular oxygen and antioxidant defense system

Rastogi

Pospı́šil

2011

J. Biomed. Opt.

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Abstract. All living organisms emit spontaneous ultraweak photon emission as a result of cellular metabolic processes. In this study, the involvement of reactive oxygen species (ROS) formed as the byproduct of oxidative metabolic processes in spontaneous ultraweak photon emission was studied in human hand skin. The effect of molecular oxygen and ROS scavengers on spontaneous ultraweak photon emission from human skin was monitored using a highly sensitive photomultiplier tube and charged coupled device camera. When spontaneous ultraweak photon emission was measured under anaerobic conditions, the photon emission was decreased, whereas under hyperaerobic condition the enhancement in photon emission was observed. Spontaneous ultraweak photon emission measured after topical application of glutathione, α-tocopherol, ascorbate, and coenzyme Q10 was observed to be decreased. These results reveal that ROS formed during the cellular metabolic processes in the epidermal cells play a significant role in the spontaneous ultraweak photon emission. It is proposed that spontaneous ultraweak photon emission can be used as a noninvasive tool for the temporal and spatial monitoring of the oxidative metabolic processes and intrinsic antioxidant system in human skin. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

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The role of singlet oxygen and triplet carbonyls in biological systems

Cited by 11 publications

References 179 publications

Using spontaneous photon emission to image lipid oxidation patterns in plant tissues

Using spontaneous photon emission to image lipid oxidation patterns in plant tissues

Sistema antioxidante envolvendo o ciclo metabólico da glutationa associado a métodos eletroanalíticos na avaliação do estresse oxidativo

Spontaneous ultraweak photon emission imaging of oxidative metabolic processes in human skin: effect of molecular oxygen and antioxidant defense system

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