Renato Jorge - Academia.edu (original) (raw)

Papers by Renato Jorge

Scientia Agricola, 2005

The effect of cadmium (Cd) on mycorrhizal association and on shoot and root Cd concentration was ... more The effect of cadmium (Cd) on mycorrhizal association and on shoot and root Cd concentration was investigated in jackbean plants under hydroponic conditions. The treatments consisted of the inoculation of three different species of arbuscular mycorrhizal fungi (AMF), Glomus etunicatum, G. intraradices and G. macrocarpum, and a non-inoculated control, two Cd (0 and 5 µmol L-1) and two P (1 and 10 mg L-1) levels in the nutrient solution. Mycorrhizal colonization, length of AMF extraradical mycelium, guaiacol peroxidase activity in roots, plant growth and root and shoot Cd and P concentrations were determined. Mycorrhizal status did not promote jackbean growth but in most of the cases mycorrhization increased root and shoot Cd concentrations. Cd ions were accumulated mainly in roots and only small amounts were translocated to the shoot. Cd addition did not affect root colonization by AMF but the AM extraradical mycelium (ERM) was sensitive to the added Cd. ERM length was reduced by 25%...

Eclética Química, 2005

A Terapia Fotodinâmica é um tratamento clínico empregado no combate a vários tipos de tumores. Ne... more A Terapia Fotodinâmica é um tratamento clínico empregado no combate a vários tipos de tumores. Nesta técnica, o paciente recebe uma certa dosagem de uma substância fotossensibilizadora que, por sua vez, acumula-se preferencialmente no tecido tumoral. Em seguida irradia-se luz visível, neste tecido, com a finalidade de se excitar o fotossensibilizador. Esta substância, excitada, pode transferir elétrons e/ou energia para o oxigênio, no estado fundamental, gerando espécies reativas de oxigênio como o radical superóxido e oxigênio singlete. O primeiro é gerado no mecanismo tipo I, pela transferência de elétrons, e o segundo no mecanismo tipo II, pela transferência de energia. Estas espécies reativas geram um estresse oxidativo, no tecido tumoral, levando as células cancerígenas à morte. Neste trabalho, foram avaliadas as propriedades fotossensibilizadoras de três porfirinas e constatou-se que as mesmas são capazes de destruir células, na presença de luz e oxigênio. Este evento foi mais...

Ciência e Agrotecnologia, 2009

cDNA arrays are a powerful tool for discovering gene expression patterns. Nylon arrays have the a... more cDNA arrays are a powerful tool for discovering gene expression patterns. Nylon arrays have the advantage that they can be re-used several times. A key issue in high throughput gene expression analysis is sensitivity. In the case of nylon arrays, signal detection can be affected by the plastic bags used to keep membranes humid. In this study, we evaluated the effect of five types of plastics on the radioactive transmittance, number of genes with a signal above the background, and data variability. A polyethylene plastic bag 69 μm thick had a strong shielding effect that blocked 68.7% of the radioactive signal. The shielding effect on transmittance decreased the number of detected genes and increased the data variability. Other plastics which were thinner gave better results. Although plastics made from polyvinylidene chloride, polyvinyl chloride (both 13 μm thick) and polyethylene (29 and 7 μm thick) showed different levels of transmittance, they all gave similarly good performances...

Phytochemistry, 2003

The relation between Al-toxicity and oxidative stress was studied for two inbred lines of maize (... more The relation between Al-toxicity and oxidative stress was studied for two inbred lines of maize (Zea mays L.), Cat100-6 (Altolerant) and S1587-17 (Al-sensitive). Peroxidase (PX), catalase (CAT) and superoxide dismutase (SOD) activities were determined in root tips of both lines, exposed to different Al 3+ concentrations and times of exposure. No increases were observed in CAT activities in either line, although SOD and PX were found to be 1.7 and 2.0 times greater than initial levels, respectively, in sensitive maize treated with 36 mM of Al 3+ for 48 h. The results indicate that Al 3+ induces the dose-and time dependent formation of reactive oxygen species (ROS) and subsequent protein oxidation in S1587-17, although not in Cat100-6. After exposure to 36 mM of Al 3+ for 48 h, the formation of 20 AE2 nmol of carbonyls per mg of protein was observed in S1587-17. The onset of protein oxidation took place after the drop of the relative root growth observed in the sensitive line, indicating that oxidative stress is not the primary cause of root growth inhibition. The presence of Al 3+ did not induce lipid peroxidation in either lines, contrasting with the observations in other species. These results, in conjunction with the data presented in the literature, indicate that oxidative stress caused by Al may harm several components of the cell, depending on the plant species. Moreover, Al 3+ treatment and oxidative stress in the sensitive maize line induced cell death in root tip cells, an event revealed by the high chromatin fragmentation detected by TUNEL analysis.

BMC Plant Biology, 2010

Background Aluminum (Al) toxicity is one of the most important yield-limiting factors of many cro... more Background Aluminum (Al) toxicity is one of the most important yield-limiting factors of many crops worldwide. The primary symptom of Al toxicity syndrome is the inhibition of root growth leading to poor water and nutrient absorption. Al tolerance has been extensively studied using hydroponic experiments. However, unlike soil conditions, this method does not address all of the components that are necessary for proper root growth and development. In the present study, we grew two maize genotypes with contrasting tolerance to Al in soil containing toxic levels of Al and then compared their transcriptomic responses. Results When grown in acid soil containing toxic levels of Al, the Al-sensitive genotype (S1587-17) showed greater root growth inhibition, more Al accumulation and more callose deposition in root tips than did the tolerant genotype (Cat100-6). Transcriptome profiling showed a higher number of genes differentially expressed in S1587-17 grown in acid soil, probably due to sec...

Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1988

Ion-exchange Experiments Solid aluminium pectinate (20-1 10 mg) and aqueous solutions of the meta... more Ion-exchange Experiments Solid aluminium pectinate (20-1 10 mg) and aqueous solutions of the metallic nitrates were placed in polyethylene flasks (ca. 30 cm3). The concentration intervals (mol dm-3) were: Zn (0.5-4.5) x FeIzl (0.3-24.0) x Cu" (0.3-3.4) x Ca (0.7-6.3) x 10-1

Objective: in this work we have investigated the photodynamic efficiency of octaethylporphyrin (O... more Objective: in this work we have investigated the photodynamic efficiency of octaethylporphyrin (OEP) and vanadyl octaethylporphyrin (VOOEP). Methods: this study was performed by the evaluation of photophysical parameters of these porphyrins, the photooxidation rate constants (k f ) of the biomolecules (tryptophan -Trp and bovine serum albumin -BSA) and the erythrocytes photodestruction percentage. Results: photophysical parameters value such as singlet oxygen quantum yield (Φ ∆ ) and triplet state lifetime (τ T ) indicated that OEP (Φ ∆ = 0.64 ±0.02, t T = 0.91 ± 0.02 ms) is more efficient than VOOEP (Φ ∆ = 0.26 ±0.02, t T = 0.22 ± 0.03 ms). The values of k f /10 -4 s -1 for Trp and BSA photoxidation demonstrated that OEP (Trp= 2.80 ± 0.05 and BSA= 2.50 ± 0.1) is more efficient than VOOEP (Trp= 0.81 ± 0.08 and BSA= 0.62 ± 0.04). The photodestruction percentage of erythrocytes revealed that the photodynamic activity of OEP is more pronounced than photoactivity of VOOEP. These results indicated that differences observed in the photodynamic activity between the porphyrins could be associated with differences in their molecular structures. Conclusion: photophysical parameters, photooxidation of biomolecules, and photodestruction of erythrocytes clearly indicate that the vanadyl group (V=O) interferes in the photoactivity of OEP, causing a considerable reduction in its efficiency.

... Gabriela Pessotti Novaes1, Marciela Belisário1, Renato Atílio Jorge4 e Joselito Nardy Ribeiro... more ... Gabriela Pessotti Novaes1, Marciela Belisário1, Renato Atílio Jorge4 e Joselito Nardy Ribeiro1* *e-mail para contato: nariber@cefetes.br RESUMO ... Photobiological Science, v.1, p.1, 2002. Ostler RB, Scully AD, Taylor AG, Gould IR, Smith TA, Waite A, Phillips D. The effect ...

Eclética Química, 2007

In this work an investigation of the photodynamic efficiency of octaethylporphyrin (OEP), vanadyl... more In this work an investigation of the photodynamic efficiency of octaethylporphyrin (OEP), vanadyl octaethylporphyrin (VOOEP), and meso-tetramesitylporphyrin (m-TMP) was done. This study was performed by the determination of photoxidation rate constants (k f ) of the tryptophan amino acid (Trp). The mechanism involved in the photoxidation of Trp was also studied using sodium azide (singlet oxygen scavenger) and deuterium oxide. The values of k f /10 -4 s -1 for Trp photoxidation demonstrated that OEP (2.80 ± 0.05) is more efficient than m-TMP (1.62 ± 0.07) and VOOEP (0.81 ± 0.08). The values of k f were reduced by the presence of sodium azide and increased by deuterium oxide indicating that singlet oxygen is responsible by OEP, VOOEP, and m-TMP photoactivity. These results indicated that differences in the photodynamic activity between porphyrins could be associated with differences in their molecular structures. The presence of vanadyl group (V=O) interferes clearly in the photodynamic activity of OEP causing a considerable reduction in its efficiency.

Photodynamic therapy is a clinical treatment that employs a combination of a photosensitizer, oxy... more Photodynamic therapy is a clinical treatment that employs a combination of a photosensitizer, oxygen, and visible light for the therapy of several kinds of tumors. This technique is characterized by the systemic administration, in the patient, of the photosensitizer, which is preferentially retained in the tumoral tissue. Its subsequent irradiation, with visible light, provokes excitation of the photosensitizer resulting in

Jornal Brasileiro de Patologia e Medicina Laboratorial, 2004

A terapia fotodinâmica (TFD) é um promissor tratamento clínico que emprega a combinação de luz vi... more A terapia fotodinâmica (TFD) é um promissor tratamento clínico que emprega a combinação de luz visível, oxigênio e uma substância fotossensibilizadora para tratar doenças de caráter oncológico. Esse tipo de tratamento induz a morte celular programada (apoptose) em tecido tumoral. No entanto, o mecanismo de indução de apoptose por TFD não está bem caracterizado. Muitos fotossensibilizadores possuem como alvo principal a mitocôndria. O tratamento com TFD causa danos nessa organela e induz a apoptose através da liberação de citocromo c, fator de indução de apoptose, Smac/DIABLO e certas pró-caspases. A liberação dessas proteínas, a partir da mitocôndria, é regulada por uma família de proteínas pró e antiapoptóticas, conhecida como família BCL-2. A proposta dessa minirrevisão é apresentar algumas publicações recentes que focalizam o envolvimento da mitocôndria em apoptose de células cancerígenas induzida por TFD. Terapia fotodinâmica Apoptose Mitocôndria unitermos Primeira submissão em 03/04/03 Última submissão em 31/07/03 Aceito para publicação em 02/09/03 Publicado em 15/06/04 J Bras Patol Med Lab • v. 40 • n. 6 • p. 383-90 • dezembro 2004 ARTIGO DE REVISÃO REVIEW ARTICLE Primeira submissão em 05/02/04

Journal of the Brazilian Chemical Society, 2008

A atividade fotodinâmica do cloro(5,10,15,20-tetrafenilporfirinato) de índio(III) (InTPP) in vitr... more A atividade fotodinâmica do cloro(5,10,15,20-tetrafenilporfirinato) de índio(III) (InTPP) in vitro foi investigado para possível uso em terapia fotodinâmica (PDT). O rendimento quântico de oxigênio singlete do InTPP (Φ ∆ = 0,72) em DMSO foi maior que da 5,10,15,20-tetrafenilporfirina (TPP) (Φ ∆ = 0,52). Os sítios de ligação entre os fotossensibilizadores e albumina bovina (BSA) são independentes e com células vermelhas de sangue humano (RBC) são cooperativos, com um e quatro sítios de ligação por molécula, respectivamente. As constantes de associação com BSA são (1,15 ± 0,07) × 10 5 e (2,6 ± 0,1) × 10 4 L mol -1 e com RBC são (2,40 ± 0,05) × 10 7 L mol -1 e (7,2 ± 0,2) × 10 4 L mol -1 para InTPP e Photofrin®, respectivamente. O InTPP foi mais eficiente do que Photofrin® em fotooxidar L-triptofano (Trp) e BSA quando maiores concentrações dos fotossensibilizadores foram utilizadas (acima de 14 µmol L −1 ). O InTPP foi 1,37 a 1,5 vezes mais eficaz em fotooxidar as RBC do que Photofrin®. Nossos resultados indicam que o InTPP pode ser usado para estudos futuros de PDT.

Journal of the Brazilian Chemical Society, 2008

Foi determinado o mecanismo de fotooxidação de albumina de soro bovino (BSA), L-triptofano (Trp) ... more Foi determinado o mecanismo de fotooxidação de albumina de soro bovino (BSA), L-triptofano (Trp) e células vermelhas do sangue (RBC) por cloro (5,10,15,20-tetrafenilporfirinato) de índio(III) (InTPP). A velocidade de fotooxidação de Trp, BSA e RBC por InTPP foi diminuída na presença de NaN 3 . A presença de D 2 O aumentou a velocidade de fotooxidação de Trp e BSA e diminuiu a de RBC. Esta diminuição provavelmente está correlacionada com a redução da constante de associação entre InTPP e RBC na presença de D 2 O. Não foi observada variação significativa na fluorescência das biomoléculas ou sobre a porcentagem de hemólise quando supressores de radicais (ferricianeto, manitol e superóxido dismutase) foram usados. Experimentos usando espectroscopia de ressonância paramagnética (EPR) mostraram que somente o 1 O 2 foi gerado por InTPP. Foi proposto um modelo cinético para a fotooxidação de Trp e BSA. A concordância entre os resultados experimentais e este modelo corrobora a predominância do mecanismo via 1 O 2 na fotooxidação das biomoléculas pelo InTPP.

Scientia Agricola, 2005

The effect of cadmium (Cd) on mycorrhizal association and on shoot and root Cd concentration was ... more The effect of cadmium (Cd) on mycorrhizal association and on shoot and root Cd concentration was investigated in jackbean plants under hydroponic conditions. The treatments consisted of the inoculation of three different species of arbuscular mycorrhizal fungi (AMF), Glomus etunicatum, G. intraradices and G. macrocarpum, and a non-inoculated control, two Cd (0 and 5 µmol L-1) and two P (1 and 10 mg L-1) levels in the nutrient solution. Mycorrhizal colonization, length of AMF extraradical mycelium, guaiacol peroxidase activity in roots, plant growth and root and shoot Cd and P concentrations were determined. Mycorrhizal status did not promote jackbean growth but in most of the cases mycorrhization increased root and shoot Cd concentrations. Cd ions were accumulated mainly in roots and only small amounts were translocated to the shoot. Cd addition did not affect root colonization by AMF but the AM extraradical mycelium (ERM) was sensitive to the added Cd. ERM length was reduced by 25%...

Eclética Química, 2005

A Terapia Fotodinâmica é um tratamento clínico empregado no combate a vários tipos de tumores. Ne... more A Terapia Fotodinâmica é um tratamento clínico empregado no combate a vários tipos de tumores. Nesta técnica, o paciente recebe uma certa dosagem de uma substância fotossensibilizadora que, por sua vez, acumula-se preferencialmente no tecido tumoral. Em seguida irradia-se luz visível, neste tecido, com a finalidade de se excitar o fotossensibilizador. Esta substância, excitada, pode transferir elétrons e/ou energia para o oxigênio, no estado fundamental, gerando espécies reativas de oxigênio como o radical superóxido e oxigênio singlete. O primeiro é gerado no mecanismo tipo I, pela transferência de elétrons, e o segundo no mecanismo tipo II, pela transferência de energia. Estas espécies reativas geram um estresse oxidativo, no tecido tumoral, levando as células cancerígenas à morte. Neste trabalho, foram avaliadas as propriedades fotossensibilizadoras de três porfirinas e constatou-se que as mesmas são capazes de destruir células, na presença de luz e oxigênio. Este evento foi mais...

Ciência e Agrotecnologia, 2009

cDNA arrays are a powerful tool for discovering gene expression patterns. Nylon arrays have the a... more cDNA arrays are a powerful tool for discovering gene expression patterns. Nylon arrays have the advantage that they can be re-used several times. A key issue in high throughput gene expression analysis is sensitivity. In the case of nylon arrays, signal detection can be affected by the plastic bags used to keep membranes humid. In this study, we evaluated the effect of five types of plastics on the radioactive transmittance, number of genes with a signal above the background, and data variability. A polyethylene plastic bag 69 μm thick had a strong shielding effect that blocked 68.7% of the radioactive signal. The shielding effect on transmittance decreased the number of detected genes and increased the data variability. Other plastics which were thinner gave better results. Although plastics made from polyvinylidene chloride, polyvinyl chloride (both 13 μm thick) and polyethylene (29 and 7 μm thick) showed different levels of transmittance, they all gave similarly good performances...

Phytochemistry, 2003

The relation between Al-toxicity and oxidative stress was studied for two inbred lines of maize (... more The relation between Al-toxicity and oxidative stress was studied for two inbred lines of maize (Zea mays L.), Cat100-6 (Altolerant) and S1587-17 (Al-sensitive). Peroxidase (PX), catalase (CAT) and superoxide dismutase (SOD) activities were determined in root tips of both lines, exposed to different Al 3+ concentrations and times of exposure. No increases were observed in CAT activities in either line, although SOD and PX were found to be 1.7 and 2.0 times greater than initial levels, respectively, in sensitive maize treated with 36 mM of Al 3+ for 48 h. The results indicate that Al 3+ induces the dose-and time dependent formation of reactive oxygen species (ROS) and subsequent protein oxidation in S1587-17, although not in Cat100-6. After exposure to 36 mM of Al 3+ for 48 h, the formation of 20 AE2 nmol of carbonyls per mg of protein was observed in S1587-17. The onset of protein oxidation took place after the drop of the relative root growth observed in the sensitive line, indicating that oxidative stress is not the primary cause of root growth inhibition. The presence of Al 3+ did not induce lipid peroxidation in either lines, contrasting with the observations in other species. These results, in conjunction with the data presented in the literature, indicate that oxidative stress caused by Al may harm several components of the cell, depending on the plant species. Moreover, Al 3+ treatment and oxidative stress in the sensitive maize line induced cell death in root tip cells, an event revealed by the high chromatin fragmentation detected by TUNEL analysis.

BMC Plant Biology, 2010

Background Aluminum (Al) toxicity is one of the most important yield-limiting factors of many cro... more Background Aluminum (Al) toxicity is one of the most important yield-limiting factors of many crops worldwide. The primary symptom of Al toxicity syndrome is the inhibition of root growth leading to poor water and nutrient absorption. Al tolerance has been extensively studied using hydroponic experiments. However, unlike soil conditions, this method does not address all of the components that are necessary for proper root growth and development. In the present study, we grew two maize genotypes with contrasting tolerance to Al in soil containing toxic levels of Al and then compared their transcriptomic responses. Results When grown in acid soil containing toxic levels of Al, the Al-sensitive genotype (S1587-17) showed greater root growth inhibition, more Al accumulation and more callose deposition in root tips than did the tolerant genotype (Cat100-6). Transcriptome profiling showed a higher number of genes differentially expressed in S1587-17 grown in acid soil, probably due to sec...

Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1988

Ion-exchange Experiments Solid aluminium pectinate (20-1 10 mg) and aqueous solutions of the meta... more Ion-exchange Experiments Solid aluminium pectinate (20-1 10 mg) and aqueous solutions of the metallic nitrates were placed in polyethylene flasks (ca. 30 cm3). The concentration intervals (mol dm-3) were: Zn (0.5-4.5) x FeIzl (0.3-24.0) x Cu" (0.3-3.4) x Ca (0.7-6.3) x 10-1

Objective: in this work we have investigated the photodynamic efficiency of octaethylporphyrin (O... more Objective: in this work we have investigated the photodynamic efficiency of octaethylporphyrin (OEP) and vanadyl octaethylporphyrin (VOOEP). Methods: this study was performed by the evaluation of photophysical parameters of these porphyrins, the photooxidation rate constants (k f ) of the biomolecules (tryptophan -Trp and bovine serum albumin -BSA) and the erythrocytes photodestruction percentage. Results: photophysical parameters value such as singlet oxygen quantum yield (Φ ∆ ) and triplet state lifetime (τ T ) indicated that OEP (Φ ∆ = 0.64 ±0.02, t T = 0.91 ± 0.02 ms) is more efficient than VOOEP (Φ ∆ = 0.26 ±0.02, t T = 0.22 ± 0.03 ms). The values of k f /10 -4 s -1 for Trp and BSA photoxidation demonstrated that OEP (Trp= 2.80 ± 0.05 and BSA= 2.50 ± 0.1) is more efficient than VOOEP (Trp= 0.81 ± 0.08 and BSA= 0.62 ± 0.04). The photodestruction percentage of erythrocytes revealed that the photodynamic activity of OEP is more pronounced than photoactivity of VOOEP. These results indicated that differences observed in the photodynamic activity between the porphyrins could be associated with differences in their molecular structures. Conclusion: photophysical parameters, photooxidation of biomolecules, and photodestruction of erythrocytes clearly indicate that the vanadyl group (V=O) interferes in the photoactivity of OEP, causing a considerable reduction in its efficiency.

... Gabriela Pessotti Novaes1, Marciela Belisário1, Renato Atílio Jorge4 e Joselito Nardy Ribeiro... more ... Gabriela Pessotti Novaes1, Marciela Belisário1, Renato Atílio Jorge4 e Joselito Nardy Ribeiro1* *e-mail para contato: nariber@cefetes.br RESUMO ... Photobiological Science, v.1, p.1, 2002. Ostler RB, Scully AD, Taylor AG, Gould IR, Smith TA, Waite A, Phillips D. The effect ...

Eclética Química, 2007

In this work an investigation of the photodynamic efficiency of octaethylporphyrin (OEP), vanadyl... more In this work an investigation of the photodynamic efficiency of octaethylporphyrin (OEP), vanadyl octaethylporphyrin (VOOEP), and meso-tetramesitylporphyrin (m-TMP) was done. This study was performed by the determination of photoxidation rate constants (k f ) of the tryptophan amino acid (Trp). The mechanism involved in the photoxidation of Trp was also studied using sodium azide (singlet oxygen scavenger) and deuterium oxide. The values of k f /10 -4 s -1 for Trp photoxidation demonstrated that OEP (2.80 ± 0.05) is more efficient than m-TMP (1.62 ± 0.07) and VOOEP (0.81 ± 0.08). The values of k f were reduced by the presence of sodium azide and increased by deuterium oxide indicating that singlet oxygen is responsible by OEP, VOOEP, and m-TMP photoactivity. These results indicated that differences in the photodynamic activity between porphyrins could be associated with differences in their molecular structures. The presence of vanadyl group (V=O) interferes clearly in the photodynamic activity of OEP causing a considerable reduction in its efficiency.

Photodynamic therapy is a clinical treatment that employs a combination of a photosensitizer, oxy... more Photodynamic therapy is a clinical treatment that employs a combination of a photosensitizer, oxygen, and visible light for the therapy of several kinds of tumors. This technique is characterized by the systemic administration, in the patient, of the photosensitizer, which is preferentially retained in the tumoral tissue. Its subsequent irradiation, with visible light, provokes excitation of the photosensitizer resulting in

Jornal Brasileiro de Patologia e Medicina Laboratorial, 2004

A terapia fotodinâmica (TFD) é um promissor tratamento clínico que emprega a combinação de luz vi... more A terapia fotodinâmica (TFD) é um promissor tratamento clínico que emprega a combinação de luz visível, oxigênio e uma substância fotossensibilizadora para tratar doenças de caráter oncológico. Esse tipo de tratamento induz a morte celular programada (apoptose) em tecido tumoral. No entanto, o mecanismo de indução de apoptose por TFD não está bem caracterizado. Muitos fotossensibilizadores possuem como alvo principal a mitocôndria. O tratamento com TFD causa danos nessa organela e induz a apoptose através da liberação de citocromo c, fator de indução de apoptose, Smac/DIABLO e certas pró-caspases. A liberação dessas proteínas, a partir da mitocôndria, é regulada por uma família de proteínas pró e antiapoptóticas, conhecida como família BCL-2. A proposta dessa minirrevisão é apresentar algumas publicações recentes que focalizam o envolvimento da mitocôndria em apoptose de células cancerígenas induzida por TFD. Terapia fotodinâmica Apoptose Mitocôndria unitermos Primeira submissão em 03/04/03 Última submissão em 31/07/03 Aceito para publicação em 02/09/03 Publicado em 15/06/04 J Bras Patol Med Lab • v. 40 • n. 6 • p. 383-90 • dezembro 2004 ARTIGO DE REVISÃO REVIEW ARTICLE Primeira submissão em 05/02/04

Journal of the Brazilian Chemical Society, 2008

A atividade fotodinâmica do cloro(5,10,15,20-tetrafenilporfirinato) de índio(III) (InTPP) in vitr... more A atividade fotodinâmica do cloro(5,10,15,20-tetrafenilporfirinato) de índio(III) (InTPP) in vitro foi investigado para possível uso em terapia fotodinâmica (PDT). O rendimento quântico de oxigênio singlete do InTPP (Φ ∆ = 0,72) em DMSO foi maior que da 5,10,15,20-tetrafenilporfirina (TPP) (Φ ∆ = 0,52). Os sítios de ligação entre os fotossensibilizadores e albumina bovina (BSA) são independentes e com células vermelhas de sangue humano (RBC) são cooperativos, com um e quatro sítios de ligação por molécula, respectivamente. As constantes de associação com BSA são (1,15 ± 0,07) × 10 5 e (2,6 ± 0,1) × 10 4 L mol -1 e com RBC são (2,40 ± 0,05) × 10 7 L mol -1 e (7,2 ± 0,2) × 10 4 L mol -1 para InTPP e Photofrin®, respectivamente. O InTPP foi mais eficiente do que Photofrin® em fotooxidar L-triptofano (Trp) e BSA quando maiores concentrações dos fotossensibilizadores foram utilizadas (acima de 14 µmol L −1 ). O InTPP foi 1,37 a 1,5 vezes mais eficaz em fotooxidar as RBC do que Photofrin®. Nossos resultados indicam que o InTPP pode ser usado para estudos futuros de PDT.

Journal of the Brazilian Chemical Society, 2008

Foi determinado o mecanismo de fotooxidação de albumina de soro bovino (BSA), L-triptofano (Trp) ... more Foi determinado o mecanismo de fotooxidação de albumina de soro bovino (BSA), L-triptofano (Trp) e células vermelhas do sangue (RBC) por cloro (5,10,15,20-tetrafenilporfirinato) de índio(III) (InTPP). A velocidade de fotooxidação de Trp, BSA e RBC por InTPP foi diminuída na presença de NaN 3 . A presença de D 2 O aumentou a velocidade de fotooxidação de Trp e BSA e diminuiu a de RBC. Esta diminuição provavelmente está correlacionada com a redução da constante de associação entre InTPP e RBC na presença de D 2 O. Não foi observada variação significativa na fluorescência das biomoléculas ou sobre a porcentagem de hemólise quando supressores de radicais (ferricianeto, manitol e superóxido dismutase) foram usados. Experimentos usando espectroscopia de ressonância paramagnética (EPR) mostraram que somente o 1 O 2 foi gerado por InTPP. Foi proposto um modelo cinético para a fotooxidação de Trp e BSA. A concordância entre os resultados experimentais e este modelo corrobora a predominância do mecanismo via 1 O 2 na fotooxidação das biomoléculas pelo InTPP.