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Characterization of a novel soybean candidate glutathione peroxidase/thioredoxin-dependent peroxidase under salt stressAdams, Ruqaiyah January 2012 (has links)
The production of reactive oxygen species (ROS) is prominent in all aerobic metabolisms including plants. For this reason, the redox homeostasis of the production and scavenging of these intermediates is imperative for growth, development and survival during unfavourable conditions. In this study, a putative glutathione peroxidase gene (Glyma17g34110) from Glycine max (soybean) was identified and analyzed. The successful characterisation of Glyma17g34110 provided evidence of it being a glutathione peroxidase using glutathione as
its preferred electron donor and substrate. Furthermore, it is known that antioxidant enzymes such as GPX exist in various tissues, performing a diverse set of functions. By a bioinformatic analysis of Glyma17g34110 and its promoter region, it was indicated that Glyma17g34110 could be a putative chloroplast protein that could play an important role in photosynthesis.One of the major factors affecting plant growth and development worldwide is abiotic stresses such as salinity. In the presence of salinity the production of harmful ROS is increased, resulting in detrimental reactions with important biological features (DNA, protein
and lipid membranes), leading to cell death. The analysis of Glyma17g34110 under salt stress revealed that it is a salt sensitive gene and thus, the down-regulation of Glyma17g34110 could be due to the lack of known defence and response cis-acting elements present in the promoter region. Furthermore, it was proven in previous studies that the application of exogenous nitric oxide (NO) increases the activity of antioxidant enzymes. In this thesis it was observed that the presence of exogenously applied NO increased the expression of Glyma17g34110 tremendously in all soybean tissues (leaves, roots and nodules) investigated.Studies have found numerous cis-acting elements to be NO responsive, however, none of these elements were found in the promoter region upstream of glyma17g34110. This suggests that novel cis-acting elements could be present in the promoter region of Glyma17g34110.Thus, increasing the expression of Glyma17g34110 during salinity in the presence of NO, as well as the identification of these novel cis-acting elements, could lead to the enhancement of the defence mechanisms against ROS, which could lead to increasing plant tolerance to stress. / >Magister Scientiae - MSc
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Protective role of glutathione peroxidase against levodopa-induced cytotoxicity in PC12 cellsKim-Han, Jeong Sook, January 1998 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves: 138-170). Also available on the Internet.
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Účinky vybraných přírodních látek na antioxidační systém organismu / Effects of selected natural substances on the antioxidant system of an organismHodková, Anna January 2016 (has links)
of study named: Effects of selected natural substances on the antioxidant system of an organism Developed: Mgr. Anna Hodková Department of Pharmacology and Toxikology, Faculty of Medicine in Pilsen, Charles University in Prague Pilsen 2016 The aim of this study was to compare the effects of selected natural substances on the antioxidant defense system under comparable conditions, focusing on influencing the activity of selenoenzymes thioredoxin reductase (TrxR-1) and glutathione peroxidase (GPx-1). Experiments were performed in rats (Wistar, male). Livers, and in some cases kidneys were collected in all experiments. Homogenates were created from the collected organs and subsequently the activity of TrxR-1 and GPx-1, glutathione reductase (GR), catalase (CAT) and superoxide dismutase (SOD), and reduced glutathione (GSH) and lipid peroxidation (LP) levels were determined. We demonstrated significant effects of selected natural substances on the redox system, including influences of selenoenzymes thioredoxin reductase and glutathione peroxidase. The biggest influence on the activity of selenoenzymes thioredoxin reductase and glutathione peroxidase had hydroxytyrosol (HT) and oleuropein (OLEU). In rat liver tissue there was a significant decrease of the activity of both above mentioned enzymes after...
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Perfil redox da classificação clínica de polipose nasal / Profile redox of the clinical classification of nasal polypsCanata, Diego Mena January 2016 (has links)
Introdução: A polipose nasal (PN) é considerada uma condição inflamatória crônica da mucosa da cavidade nasal e seios paranasais de etiologia não muito clara. Há poucos dados sobre alterações epiteliais em PN e sua relação com a ação dos radicais livres. Muitas doenças estão ligadas a danos causados por espécies reativas de oxigênio (ROS) e de nitrogênio (RNSS) e ocorrem de um desequilíbrio entre eles e antioxidantes, o que for maior atividade de espécies reativas, o que chamamos de estresse oxidativo. Objetivo: O objetivo principal deste estudo é avaliar o estresse oxidativo em pólipos removidos cirurgicamente em 3 grupos de pacientes com polipose nasal (com PN unicamente, PN associado à asma e PN associado à asma e intolerância ao ácido acetilsalicílico) a fim de elucidar possíveis diferenças no perfil redox nestes grupos. Material e Métodos: Cinquenta e nove pacientes com diagnóstico de polipose nasal foram divididos em três grupos clínicos: um grupo controle PN unicamente, um grupo asma (PN associado à asma) e um grupo Widal (PN associado à asma e intolerância ao ácido acetilsalicílico). Medição e Resultados Principais: Neste trabalho defesas enzimáticas (superóxido dismutase, consumo de peróxido de hidrogênio, glutationa peroxidase e glutationa S-transferase) e defesas não enzimáticas (glutationa total, nitritos e nitratos, vitamina C e E) foram analisados. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo asma, o consumo de peróxido de hidrogênio, atividade da glutationa peroxidase, níveis de malondialdeído e vitamina E foram significativamente menores do que no grupo de controle. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo Widal foram encontrados níveis significativamente maiores de glutationa e nitritos e nitratos em relação ao grupo controle. Não foram encontradas diferenças entre os grupos em relação ao nível de carbonila e glutationa, tamanho dos pólipos, atividades da superóxido dismutase e S-transferase. Conclusões: A classificação redox dos grupos de PN foi parcialmente alcançada. Os pólipos do grupo asma possuem alterações nas defesas enzimáticas relacionadas com o peróxido de hidrogênio e a peroxidação lipídica, enquanto pólipos do grupo Widal apresentaram alterações nos níveis de óxido nítrico e glutationa. / Introduction: Nasal polyposis (NP) is considered a chronic inflammatory condition of the mucosa of the nasal cavity and paranasal sinuses of etiology is not very clear. There are few data on epithelial changes in nasal polyposis and its relation to the action of free radicals. Many diseases are linked to damage caused by reactive oxygen species (ROS) and nitrogen (RNSs) and occur from an imbalance between them and antioxidants, whichever is greater activity of reactive species, what we call oxidative stress. Objective: The primary objective of this study is to evaluate oxidative stress in polyps surgically removed in 3 groups of patients with nasal polyposis, in order to elucidate possible differences in redox profile in these groups. Methods: Fifty nine patients diagnosed with nasal polyposis were divided into three groups: a control group, an asthma group (NP with asthma) and a Widal group (NP with asthma and aspirin intolerance) in which patients had an association of NP, asthma and aspirin intolerance. Measurement and main results: In this work enzymatic defenses (superoxide dismutase, hydrogen peroxide consumption, glutathione peroxidase and glutathione S-transferase) and non-enzymatic defenses (total glutathione, measurement of nitrites and nitrates, vitamin C and E) were analyzed. Also the measurement of damage in lipids (malondialdehyde) and proteins (carbonyl) was conducted. In the asthma group, hydrogen peroxide consumption, glutathione peroxidase activity, malondialdehyde, and vitamin E levels were significantly lower than in the control group. The Widal group showed significant higher glutathione levels, nitrite and nitrate levels than found in the control group. No differences were found among the groups regarding carbonyl level, polyp size, superoxide dismutase, and glutathione S-transferase activities. Conclusions: The redox classification of the groups of NP was partly achieved. Polyps of patients with asthma have changes in enzymatic defense pathways related to hydrogen peroxide and lipid peroxidation while polyps of patients with Widal triad present changes in nitric oxide and glutathione.
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Avaliação do potencial antioxidante de beta-selenoaminas / Evaluation of Antioxidant Potential of β-selenoaminesPrestes, Alessandro de Souza 22 February 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The antioxidant properties of selenium organic compounds have been largely investigated in the last decades, especially because the oxidative stress is directly related to various chronic-degenerative deseases. However, a few studies verify the action of nucleophlilic or electrophilic radicals on the protective activity of selenium compounds. In this work, it was evaluated the influence of different substituent radicals on the antioxidant activities of β-selenoamines. The capacity of β-selenoaminas in mimicry the glutathione peroxidase (GPx) activity and/or be substrate to the hepatic thioredoxinereductase (TrxR) enzyme were also investigated in experimental modelsin vitro.In DPPH assay, the β-selenoamines tested did not show antioxidant activity when compared to acorbic acid (AA). However, similar to compound (PhSe)2, the β-selenoamines with p-methoxy and tosylradicals were effective in preventing the lipid peroxidation induced by Fe2SO4. The compounds with other radicals did not exhibit the same activity. The β-selenoamine with the substituent group p-methoxy also showed mimetic activity to GPx and was reduced by hepatic TrxR. Furthermore, a positive correlation was observed among these parameters to β-selenoamines, which was not found in the results obtained with (PhSe)2. The data of this work show the influence of different substituent radicals on activity of organic selenium compounds and point the use of β-selenoaminas as pharmacological promissor compounds in in vivo experimental models. / As propriedades antioxidantes de compostos orgânicos de selênio têm sido amplamente investigadas nas últimas décadas, especialmente pelo fato do estresse oxidativo estar diretamente relacionado a uma grande variedade de doenças crônico-degenerativas. Contudo, poucos estudos têm verificado a ação exercida por radicais nucleofílicos ou eletrofílicos na atividade protetora de compostos de selênio. Neste trabalho foi avaliada a influência de diferentes radicais substituintes sobre a atividade antioxidante de β-selenoaminas. A capacidade das β-selenoaminas em mimetizar a atividade da glutationa peroxidase (GPx) e/ou serem substratos para a enzima tiorredoxina redutase hepática (TrxR) também foram investigadas em modelos experimentais in vitro. No ensaio de DPPH , as β-selenoaminas testadas não apresentaram atividade antioxidante quando comparadas ao ácido ascórbico (AA). Contudo, assim como o composto disseleneto de difenila (PhSe)2, as β-selenoaminas com grupos p-metóxi e tosil na estrutura foram efetivas em prevenir a peroxidação lipídica induzida por Fe2SO4. Os compostos com outros radicais não apresentaram a mesma atividade. A β-selenoamina com o grupo substituinte p-metóxi também apresentou atividade mimética à GPx e foi reduzida pela TrxR hepática. Além disso, uma correlação positiva foi encontrada entre estes parâmetros para as β-selenoaminas; o que não foi observado quando considerados os resultados obtidos com o composto (PhSe)2. Os dados do presente trabalho mostram a influência de diferentes radicais substituintes na atividade de compostos orgânicos de selênio, bem como, aponta o uso de β-selenoaminas como compostos promissores farmacologicamente em modelos experimentais in vivo.
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Perfil redox da classificação clínica de polipose nasal / Profile redox of the clinical classification of nasal polypsCanata, Diego Mena January 2016 (has links)
Introdução: A polipose nasal (PN) é considerada uma condição inflamatória crônica da mucosa da cavidade nasal e seios paranasais de etiologia não muito clara. Há poucos dados sobre alterações epiteliais em PN e sua relação com a ação dos radicais livres. Muitas doenças estão ligadas a danos causados por espécies reativas de oxigênio (ROS) e de nitrogênio (RNSS) e ocorrem de um desequilíbrio entre eles e antioxidantes, o que for maior atividade de espécies reativas, o que chamamos de estresse oxidativo. Objetivo: O objetivo principal deste estudo é avaliar o estresse oxidativo em pólipos removidos cirurgicamente em 3 grupos de pacientes com polipose nasal (com PN unicamente, PN associado à asma e PN associado à asma e intolerância ao ácido acetilsalicílico) a fim de elucidar possíveis diferenças no perfil redox nestes grupos. Material e Métodos: Cinquenta e nove pacientes com diagnóstico de polipose nasal foram divididos em três grupos clínicos: um grupo controle PN unicamente, um grupo asma (PN associado à asma) e um grupo Widal (PN associado à asma e intolerância ao ácido acetilsalicílico). Medição e Resultados Principais: Neste trabalho defesas enzimáticas (superóxido dismutase, consumo de peróxido de hidrogênio, glutationa peroxidase e glutationa S-transferase) e defesas não enzimáticas (glutationa total, nitritos e nitratos, vitamina C e E) foram analisados. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo asma, o consumo de peróxido de hidrogênio, atividade da glutationa peroxidase, níveis de malondialdeído e vitamina E foram significativamente menores do que no grupo de controle. Também foi realizada a medição de danos em lipídios (malondialdeído) e proteínas (carbonila). No grupo Widal foram encontrados níveis significativamente maiores de glutationa e nitritos e nitratos em relação ao grupo controle. Não foram encontradas diferenças entre os grupos em relação ao nível de carbonila e glutationa, tamanho dos pólipos, atividades da superóxido dismutase e S-transferase. Conclusões: A classificação redox dos grupos de PN foi parcialmente alcançada. Os pólipos do grupo asma possuem alterações nas defesas enzimáticas relacionadas com o peróxido de hidrogênio e a peroxidação lipídica, enquanto pólipos do grupo Widal apresentaram alterações nos níveis de óxido nítrico e glutationa. / Introduction: Nasal polyposis (NP) is considered a chronic inflammatory condition of the mucosa of the nasal cavity and paranasal sinuses of etiology is not very clear. There are few data on epithelial changes in nasal polyposis and its relation to the action of free radicals. Many diseases are linked to damage caused by reactive oxygen species (ROS) and nitrogen (RNSs) and occur from an imbalance between them and antioxidants, whichever is greater activity of reactive species, what we call oxidative stress. Objective: The primary objective of this study is to evaluate oxidative stress in polyps surgically removed in 3 groups of patients with nasal polyposis, in order to elucidate possible differences in redox profile in these groups. Methods: Fifty nine patients diagnosed with nasal polyposis were divided into three groups: a control group, an asthma group (NP with asthma) and a Widal group (NP with asthma and aspirin intolerance) in which patients had an association of NP, asthma and aspirin intolerance. Measurement and main results: In this work enzymatic defenses (superoxide dismutase, hydrogen peroxide consumption, glutathione peroxidase and glutathione S-transferase) and non-enzymatic defenses (total glutathione, measurement of nitrites and nitrates, vitamin C and E) were analyzed. Also the measurement of damage in lipids (malondialdehyde) and proteins (carbonyl) was conducted. In the asthma group, hydrogen peroxide consumption, glutathione peroxidase activity, malondialdehyde, and vitamin E levels were significantly lower than in the control group. The Widal group showed significant higher glutathione levels, nitrite and nitrate levels than found in the control group. No differences were found among the groups regarding carbonyl level, polyp size, superoxide dismutase, and glutathione S-transferase activities. Conclusions: The redox classification of the groups of NP was partly achieved. Polyps of patients with asthma have changes in enzymatic defense pathways related to hydrogen peroxide and lipid peroxidation while polyps of patients with Widal triad present changes in nitric oxide and glutathione.
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Modulação da secreção de insulina por estresse oxidativo induzido em ilhotas pancreáticas de animais submetidos à desnutrição protéica / Oxidative stress modulation of insulin secretion in protein undernourished rats' pancreatic isletCappelli, Ana Paula Gameiro, 1984- 12 November 2009 (has links)
Orientador: Everardo Magalhães Carneiro / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-16T00:20:04Z (GMT). No. of bitstreams: 1
Cappelli_AnaPaulaGameiro_M.pdf: 8746314 bytes, checksum: fffd531f3decda018f572cfc7c7f2be6 (MD5)
Previous issue date: 2009 / Resumo: A desnutrição protéica promove redução da secreção de insulina devida inúmeras alterações moleculares nas células B pancreáticas. Recentemente foi demonstrado que o estado redox pode modular a secreção de insulina em condições fisiológicas. No entanto, a correlação entre as alterações no estado redox e na secreção de insulina em ratos submetidos à desnutrição protéica não é conhecida. Assim, nosso objetivo foi avaliar o impacto do estresse oxidativo na secreção de insulina em ilhotas de ratos desnutridos. Ratos machos Wistar foram tratados com dieta normoprotéica (NP-17%) ou hipoprotéica (LP-6%) por 60 dias. Após isolamento das ilhotas, foi medida atividade e o conteúdo protéico das enzimas antioxidantes SOD, GPx e a CAT. Para a secreção estática de insulina, as ilhotas foram pré-incubadas em 5.6 mM de glicose (GLI) com ou sem H2O2, na ausência ou presença de n-acetil cisteína (NAC) e posteriormente incubadas em diferentes concentrações de GLI. Observamos aumento da atividade da SOD (21.18±2.1-30.5.±2 µmoles/min/mg proteína NP-LP respectivamente), redução na CAT (9±1.2-5.22±0.73 µmoles/min/mg proteína NP-LP respectivamente) e nenhuma alteração na GPx em ilhotas de ratos desnutrido comparada com ilhotas de ratos controle. Apesar de observarmos tendência de aumento no conteúdo protéico das enzimas antioxidantes em LP, não houve diferença significativa de nenhuma das enzimas. A secreção de insulina de ratos LP que ficaram expostas a
33mM de glicose na incubação, retornou a níveis basais (GLI 2.8 mM) quando préincubado com 100 µM de H2O2, enquanto para as ilhotas de ratos controle foi necessário a adição de 300 ?M de H2O2 na pré-incubação para retornar aos níveis basais. Na presença de 10 mM de NAC + 150 µM de H2O2, durante a pré-incubação, e posterior incubação em 33 mM de glicose, observou-se redução significante da secreção de NP e aumento em LP. Estes resultados sugerem que as ilhotas pancreáticas de ratos desnutridos pré tratadas com H2O2 e posteriormente expostas a altas concentrações de glicose, são mais sensíveis ao H2O2 possivelmente devido à capacidade reduzida de detoxificação de espécies reativas de oxigênio (EROS). / Abstract: Protein malnutrition induces pacreatic B-cells molecular alterations, reducing insulin secretion. It has been recently demonstrated that redox status may control insulin secretion under physiological conditions. However, protein malnutrition effects in redox modulation of insulin secretion is unknown. Thus, our aim was to evaluate oxidative stress impact upon insulin secretion in isolated islets from protein undernourished rats. Male Wistar rats were treated with normoproteic diet (NP-17%) or with a low protein diet (LP-6%) for sixty days. After islets isolation, it was measured antioxidant enzymes SOD, GPX and CAT activities and protein content. For insulin secretion measurement, islets were pre-incubated with glucose 5.6 (GLI) mM with or without H2O2 at the presence and absence of N-acetyl-cisteyne (NAC) and after that islets were incubated with diferent GLI concentration. SOD and CAT activities were significant increased (21.18±2.1-30.5.±2 µmoles/min/mg protein for NP-LP respectively) and decreased (9±1.2-5.22±0.73 µmoles/min/mg protein for NP-LP respectively) respectively, whereas GPX did not show any alteration. Despite a tendency of increase in the LP protein
content of antioxidant enzymes, no significant differences were observed. When incubated with glucose 33mM, LP insulin secretion returned to baseline values (GLI 2.8 mM) when it was pre-incubated with H2O2 100 µM, whereas NP islets returned to baseline levels when pre-incubated with H2O2 300 ?M. When islets were pre-incubated with NAC 10 mM + H2O2 150 µM and further incubated with glucose 33 mM, insulin secretion was reduced in NP, whereas in LP it was increased. Taken together, these datasuggest that pancreatic islets from undernourished rats when pre-treated with H2O2 and thereafter challenged with high glucose concentrations are more sensitive to H2O2, probably due to their lower capacity to detoxify reactive oxygen species (ROS). / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
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Avaliação do estresse oxidativo sob a resposta imune de bovinos infectados pelo vírus da leucose enzoótica bovina / Evaluation of oxidative stress on the immune response of bovine leukemia virus-infected dairy cowsFernando Nogueira de Souza 21 May 2010 (has links)
Foi demonstrado o envolvimento das espécies reativas de oxigênio (ERO) na patogênese de algumas retroviroses, levando muitas vezes à progressão e/ou persistência das mesmas. No entanto, o papel das espécies reativas de oxigênio resultante da modulação do sistema antioxidante, e seu envolvimento na infecção de bovinos naturalmente infectados pelo VLEB, até o presente trabalho, não tinha sido ainda investigado. Desta forma, o presente estudo objetivou-se avaliar o envolvimento do estresse oxidativo na infecção pelo VLEB em bovinos naturalmente infectados, associado ou não ao estabelecimento da linfocitose persistente (LP). Assim, a avaliação do estresse oxidativo se deu pelo teor de malondialdeído, concentração de glutationa reduzida, atividade da glutationa peroxidase e da superóxido dismutase, e pela atividade antioxidante total; e a resposta imune pela quantificação das subpopulações de linfócitos, função fagocítica e produção intracelular de peróxido de hidrogênio de leuccitos polimorfonucleares, morte celular e proliferação linfocitária, além da avaliação hematológica e sorodiagnóstico da leucose enzoótica bovina (LEB). Os resultados do presente estudo apontaram para o envolvimento do estresse oxidativo na infecção pelo vírus da leucose enzoótica bovina, dado pela menor concentração de glutationa peroxidase e a tendência a menor atividade da superxido dismutase eritrocitárias nos animais infectados pelo VLEB, não podendo, contudo, ser associado à fase da infecção. Ademais, os marcadores de estresse oxidativo não apresentaram alterados nem sequer a atividade antioxidante total destes animais. Além disso, o presente trabalho apontou para menor proliferação de linfócitos e redução da apoptose de células CD5+ nos animais infectados pelo VLEB manifestando LP, corroborados pelo significante aumento da população de linfcitos B (CD21+), e dos principais co-marcadores das células infectadas, no caso células CD5+ e CD11b+, nestes animais. No entanto, não observou diferenças significativas na população de linfócitos T destes animais, nem sequer alteração da capacidade fagocítica e produção intracelular de peróxido de hidrogênio pela população de leucócitos polimorfonucleares nos animais infectados. / Abundant observations of multiple pathogenic interactions between reactive oxygen species (ROS) and the pathogenesis of some retroviruses have drawn attention to role of ROS on disease progression and/or persistence of infection. Therefore, the role of the oxidative stress resulted from the modulation of the antioxidant system in dairy cows naturally infected with BLV has not been studied yet. So, the present study tries to investigate the involvement of oxidative stress in dairy cows naturally infected with BLV associated or not with the persistent lymphocytosis (PL). Thus, the oxidative stress was evaluated by the malondialdehyde, reduced glutathione content, and by the activity of glutathione peroxidase and superoxide dismutase, and also total antioxidant activity. The immune response was also evaluated by the quantification of lymphocyte subsets, lymphocyte proliferation, polymorfonuclear leukocytes phagocytosis and intracellular hydrogen peroxide production, and cell death. The results of the present work point out to an involvement of oxidative stress in dairy cows naturally infected with BLV, given by a lower glutathione peroxidase activity and also a tendency towards lower superoxide dismutase activity, but it can be not associated with PL. Futhermore, the oxidative stress markers and also the total antioxidant status was not altered in infected animals. The present study also showed a lower lymphocyte proliferarion and apoptosis rates of CD5+ cells, strengthen by a higher B cells (CD21+) counts and also by a significant augment of CD5+ and CD11b+ positive cells that are often co-expressed by the infected cells. Although, no significant difference was observed in T cells counts. Moreover, the phagocytosis rates and the intracellular hydrogen peroxide production by the polymorphonuclear leukocytes are not altered in BLV infected dairy cows.
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Characterization of a novel soybean candidate glutathione peroxidase/thioredoxin-dependent peroxidase under salt stressAdams, Ruqaiyah January 2012 (has links)
>Magister Scientiae - MSc / The production of reactive oxygen species (ROS) is prominent in all aerobic metabolisms including plants. For this reason, the redox homeostasis of the production and scavenging of these intermediates is imperative for growth, development and survival during unfavourable conditions. In this study, a putative glutathione peroxidase gene (Glyma17g34110) from Glycine max (soybean) was identified and analyzed. The successful characterisation of Glyma17g34110 provided evidence of it being a glutathione peroxidase using glutathione as its preferred electron donor and substrate. Furthermore, it is known that antioxidant enzymes such as GPX exist in various tissues, performing a diverse set of functions. By a bioinformatic analysis of Glyma17g34110 and its promoter region, it was indicated that Glyma17g34110 could be a putative chloroplast protein that could play an important role in photosynthesis.One of the major factors affecting plant growth and development worldwide is abiotic stresses such as salinity. In the presence of salinity the production of harmful ROS is increased, resulting in detrimental reactions with important biological features (DNA, protein and lipid membranes), leading to cell death. The analysis of Glyma17g34110 under salt stress revealed that it is a salt sensitive gene and thus, the down-regulation of Glyma17g34110 could be due to the lack of known defence and response cis-acting elements present in the promoter region. Furthermore, it was proven in previous studies that the application of exogenous nitric oxide (NO) increases the activity of antioxidant enzymes. In this thesis it was observed that the presence of exogenously applied NO increased the expression of Glyma17g34110 tremendously in all soybean tissues (leaves, roots and nodules) investigated.Studies have found numerous cis-acting elements to be NO responsive, however, none of these elements were found in the promoter region upstream of glyma17g34110. This suggests that novel cis-acting elements could be present in the promoter region of Glyma17g34110.Thus, increasing the expression of Glyma17g34110 during salinity in the presence of NO, as well as the identification of these novel cis-acting elements, could lead to the enhancement of the defence mechanisms against ROS, which could lead to increasing plant tolerance to stress.
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Retinopathy of Prematurity: An Oxidative Stress Neonatal DiseaseStone, William L., Shah, Darshan, Hollinger, Shawn M. 01 January 2016 (has links)
Proteomics is the global study of proteins in an organism or a tissue/fluid and is clinically relevant since most disease states are accompanied by specific alterations in an organism's proteome. This review focuses on the application of proteomics to neonatology with particular emphasis on retinopathy of prematurity (ROP), which is a disease in which oxidative stress plays a key pathophysiological role. Oxidative stress is a physiologically relevant redox imbalance caused by an excess of reactive oxygen (ROS) or reactive nitrogen oxide species (RNOS). A major conclusion of this review is that proteomics may be the optimal technology for studying neonatal diseases such as ROP, particularly in the setting of a neonatal intensive care unit (NICU). Proteomics has already identified a number of ROP serum biomarkers. This review will also suggest novel therapeutic approaches to ROP and other neonatal oxidative stress diseases (NOSDs) based on a systems medicine approach.
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