OBJECTIVE: The objective of this work was a further investigation of redox mechanisms of laser phototherapy on the cellular level. BACKGROUND DATA: Cytochrome c oxidase, the terminal enzyme of the mitochondrial respiratory chain, is believed to work as the photoacceptor to modulate cellular metabolism in laser phototherapy. MATERIALS AND METHODS: The changes in the absorption spectra of HeLa-cell monolayers before and after irradiation at 632.8 nm using fast multi-channel recording were evaluated by the intensity ratio between the peaks at 770 and 670 nm (intensity ratio criterion). RESULTS: By the intensity ratio criterion, the irradiation effects (reduction or oxidation of the photoacceptor) depended on the initial redox status of cytochrome c oxidase. The irradiation (three times at 632.8 nm, dose = 6.3 x 103 J/m(2), tau(irrad.) = 10 sec, tau(record.) = 600 msec) of cells initially characterized by relatively oxidized cytochrome c oxidase caused first a reduction of the photoacceptor, and then its oxidation (a bell-shaped curve). The irradiation by the same scheme of the cells with initially relatively reduced cytochrome c oxidase caused first oxidation and then a slight reduction of the enzyme (a curve opposite to the bell-shaped curve). CONCLUSION: The experimental results of our work demonstrate that irradiation at 632.8 nm causes either a (transient) relative reduction of the photoacceptor, putatively cytochrome c oxidase, or its (transient) relative oxidation, depending on the initial redox status of the photoacceptor. The maximum in the bell-shaped dose-dependence curve or the minimum of the reverse curve is the turning point between the prevailing of oxidation or reduction processes. Our results are evidence that the bell-shaped dose dependences recorded for various cellular responses are characteristic also for redox changes in the photoacceptor, cytochrome c oxidase.
OBJECTIVE: The objective of this work was a further investigation of redox mechanisms of laser phototherapy on the cellular level. BACKGROUND DATA: Cytochrome c oxidase, the terminal enzyme of the mitochondrial respiratory chain, is believed to work as the photoacceptor to modulate cellular metabolism in laser phototherapy. MATERIALS AND METHODS: The changes in the absorption spectra of HeLa-cell monolayers before and after irradiation at 632.8 nm using fast multi-channel recording were evaluated by the intensity ratio between the peaks at 770 and 670 nm (intensity ratio criterion). RESULTS: By the intensity ratio criterion, the irradiation effects (reduction or oxidation of the photoacceptor) depended on the initial redox status of cytochrome c oxidase. The irradiation (three times at 632.8 nm, dose = 6.3 x 103 J/m(2), tau(irrad.) = 10 sec, tau(record.) = 600 msec) of cells initially characterized by relatively oxidized cytochrome c oxidase caused first a reduction of the photoacceptor, and then its oxidation (a bell-shaped curve). The irradiation by the same scheme of the cells with initially relatively reduced cytochrome c oxidase caused first oxidation and then a slight reduction of the enzyme (a curve opposite to the bell-shaped curve). CONCLUSION: The experimental results of our work demonstrate that irradiation at 632.8 nm causes either a (transient) relative reduction of the photoacceptor, putatively cytochrome c oxidase, or its (transient) relative oxidation, depending on the initial redox status of the photoacceptor. The maximum in the bell-shaped dose-dependence curve or the minimum of the reverse curve is the turning point between the prevailing of oxidation or reduction processes. Our results are evidence that the bell-shaped dose dependences recorded for various cellular responses are characteristic also for redox changes in the photoacceptor, cytochrome c oxidase.
Authors: Lucas Capalonga; Marlus Karsten; Vítor Scotta Hentschke; Douglas Dalcin Rossato; Maurício Pinto Dornelles; Anelise Sonza; Vanderlei Salvador Bagnato; Cleber Ferraresi; Nivaldo Antonio Parizotto; Pedro Dal Lago Journal: Lasers Med Sci Date: 2016-04-08 Impact factor: 3.161
Authors: Adenilson de Souza da Fonseca; Giuseppe Antonio Presta; Mauro Geller; Flavia de Paoli; Samuel Santos Valença Journal: Lasers Med Sci Date: 2011-06-24 Impact factor: 3.161
Authors: Cleber Ferraresi; Thomas Beltrame; Fernando Fabrizzi; Eduardo Sanches Pereira do Nascimento; Marlus Karsten; Cristina de Oliveira Francisco; Audrey Borghi-Silva; Aparecida Maria Catai; Daniel Rodrigues Cardoso; Antonio Gilberto Ferreira; Michael R Hamblin; Vanderlei Salvador Bagnato; Nivaldo Antonio Parizotto Journal: Physiother Theory Pract Date: 2015-01-14 Impact factor: 2.279
Authors: Heliton S Antunes; Gabriel Wajnberg; Marcos B Pinho; Natasha Andressa Nogueira Jorge; Joyce Luana Melo de Moraes; Claudio Gustavo Stefanoff; Daniel Herchenhorn; Carlos M M Araújo; Celia Maria Pais Viégas; Mariana P Rampini; Fernando L Dias; Patricia Savio de Araujo-Souza; Fabio Passetti; Carlos G Ferreira Journal: Lasers Med Sci Date: 2017-08-24 Impact factor: 3.161
Authors: José Carlos Tatmatsu-Rocha; Cleber Ferraresi; Michael R Hamblin; Flávio Damasceno Maia; Nilberto Robson Falcão do Nascimento; Patricia Driusso; Nivaldo Antonio Parizotto Journal: J Photochem Photobiol B Date: 2016-09-12 Impact factor: 6.252