Dissertations / Theses on the topic 'GSH'
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Guo, Ningning. "GSH : a new candidate neuropeptide in the CNS." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29856.
Full textMedicine, Faculty of
Graduate
Govender, Prenevin. "Retrospective review of radical cystectomies at GSH 1993-2007." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/10503.
Full textThe objective of the thesis was to look at the epidemiology of patients needing this procedure, clinical presentation and investigation, pathology, complications related to the procedure, adjuvant and neoadjuvant treatment, and survival.
Atar, Murat [Verfasser]. "Synthese und photophysikalische Untersuchung von phthalimidbasierten modularen Fluoreszenzsonden zur Detektion von ROS, GSH/GST und Cyanid / Murat Atar." München : Verlag Dr. Hut, 2018. http://d-nb.info/1161250433/34.
Full textIgbaria, Aeid. "Functional redox compartmentation of GSH in the yeast Saccharomyces cerevisiae." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112189.
Full textCys residue oxidation is a widespread biochemical modification occurring in all eukaryotic cells compartments. It serves oxidative protein folding in the endoplasmic reticulum (ER), protein import in the intermembrane space of mitochondria (IMS), and it has a regulatory role in the mitochondrial matrix and in the cytosol where it controls enzymes and signaling regulatory proteins activity. In all these processes, reversibility of Cys residue oxidation is a crucial feature. Two potent oxidoreductase systems, the glutathione (GSH) and thioredoxin pathways, catalyze disulfide bond reduction, and presumably control most thiol-redox-dependent cellular processes. However, despite tremendous knowledge of their enzymology, little is known about the physiological features of these systems in eukaryotes. To determine the physiologic importance of these functions and sort out which of them accounts for the GSH requirement for viability, we performed a comprehensive analysis of yeast cells depleted of or containing toxic levels of GSH. Both conditions triggered an intense iron-starvation-like response and impaired the activity of extra-mitochondrial ISC enzymes, but did not impact thiol-redox maintenance, except high glutathione levels that altered oxidative protein folding in the endoplasmic reticulum. While iron partially rescued the ISC maturation and growth defects of GSH-depleted cells, genetic experiments indicated that unlike thioredoxin, glutathione could not support by itself the thiolredox duties of the cell. We propose that glutathione is essential by its requirement in ISC assembly but only serves as a thioredoxin back up in cytosolic thiol-redox maintenance. Glutathione high physiologic levels are thus meant to insulate its function in iron metabolism from variations of its concentration during redox stresses, a model challenging the traditional view of it as prime actor in cytosolic thiol-redox control.Our preliminary data on the distribution of GSH inside cells collected by monitoring the redox state of rxYFP targeted to different cell compartments (ER, Matrix, Cytosol and IMS) in HGT1 cells indicate a specific transport of GSH into the ER and export of GSSG out of it. We were able to characterize two ABC transporters on which their deletion modify the redox state of the ER to more oxidizing and result in accumulation of higher GSSG content compared to WT. These data were confirmed by looking to the redox state of the PDI1 and ERO1 (WT and hyper active), all together suggest a role of these transporters in GSSG export from the ER, and that GSH flux between the different compartments is highly regulated
Cruzat, Vinicius Fernandes. "Efeito da suplementação com L-glutamina livre e na forma de dipeptídeo sobre eixo glutamina-glutationa, sistema imune, sistema inflamatório e vias de sinalização proteica em camundongos submetidos à endotoxemia." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/9/9132/tde-23052013-152405/.
Full textSepsis is the leading cause of death inintensive care units (ICUs) in the world.The availability ofthe most abundant amino acid in the body, glutamine, is reduced in this situation, fact that contribute to the complicated catabolic state of sepsis. In the present study, we investigated the effects of oral supplementation with L-glutamine and L-alanine (GLN+ALA), both in their free form and as a dipeptide, L-alanyl-L-glutamine (DIP) on glutamine-glutathione axis (GSH), immune and inflammatory system, heat shock proteins (HSPs) expression and gene expressions involved in protein signaling pathways during endotoxemia. C57/B6 mice were subjected to endotoxemia (Escherichia coli LPS, 5 mg.kg-1, LPS group) and supplemented for 48 hours with L-glutamine (1 g.kg-1) plus L-alanine(0.61 g.kg-1, GLN+ALA-LPS group) or 1.49 g.kg-1of DIP (DIP-LPS group). Endotoxemia promoted depletion glutamine concentration in plasma (71%), skeletal muscle (50%) and liver (49%), when compared to the CTRL group, and was restored in the DIP-LPS e GLN+ALA-LPS (P<0.05), fact that attenuate the reduction of GSH and the redox state (GSSG/GSH rate) in circulating erythrocytes, liver and muscle (P<0.05). Supplementations in endotoxemic mice resulted in upregulation of GSR, GCLC and GPX1 genes in muscle and liver. Plasma concentration of TNF-α, IL-6, IL-1β and IL-10 were attenuated by supplementation as well as the expression of mRNAs involved in the inflammatory response, activated by NFκ-B pathway (P <0.05). At the same time, high proliferative capacity of circulating T and B lymphocytes GLN+ALA-LPS e DIP-LPS were observed. HSPs (protein and mRNAs) and in muscle were restored by the supplements, however, the mRNAs expression related to the synthesis and degradation of protein pathways was only stimulated in the liver (P <0.05). Our results demonstrate that oral supplementation with GLN+ALA or DIP can be used as clinically nutritional methods to reverse the depression of body glutamine availability during sepsis induced by LPS, impacting on the glutamine-glutathione axis, immune and inflammatory system.
İlhan, Mücahit Aydoğan Nevres Hürriyet. "Gonartrozlu hastalarda viskosuplementasyon sonrası MDA, DOS, GSH-Px ve katalaz düzeyleri /." Isparta : SDÜ Tıp Fakültesi, 2006. http://tez.sdu.edu.tr/Tezler/TT00254.pdf.
Full textRABELO, Natielle Ferreira. "Influência da glutationa (GSH) nos registros eletrorretinográficos de ratos wistar adultos." Universidade Federal do Pará, 2014. http://repositorio.ufpa.br/jspui/handle/2011/8134.
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A glutationa (GSH) é uma molécula que intervêm em diversos processos biológicos, conhecida principalmente pela sua ação antioxidante. Atualmente, esse tripeptídeo constituído de glutamato, cisteína e glicina têm sido amplamente estudados pela sua possível ação como neurotransmissor e nuromodulador no CNS. No presente trabalho foi avaliada a ação dessa molécula através do eletrorretinograma, para avaliar a resposta em massa da retina, produzida após estimulação luminosa. Métodos: foram realizadas injeções intravítreas de GSH em diferentes concentrações (1, 5 e 10 mM) e de PBS (controle) em ratos Wistar. O protocolo de avaliação consistiu de 6 estímulos em diferentes condições de adaptação: resposta Escotópica de bastonetes e resposta Escotópica máxima, após adaptação ao escuro de pelo menos 12h; resposta Fotópica de cones, após 10 min de adaptação ao claro, com a utilização de filtros para a avaliação da subpopulações de cones UV e S; e a resposta ao estímulo de flicker em 12 Hz. Os principais parâmetros analisados foram as amplitudes das ondas –a e –b e seus respectivos tempos implícitos e a amplitude das ondas –b do flicker. RESULTADOS: os resultados mostram alterações nas respostas com a diminuição da amplitude da ondab do ERG em todos os estímulos. Quando realizado o teste de múltiplas comparações, foram observadas diferenças entre os grupos controle e GSH 5mM e GSH 10mM. Alterações na amplitude da onda-a só foram observados na resposta Escotópica máxima, com significativa diminuição da amplitude. Os tempo de latência das respostas não apresentaram alterações em nenhum grupo avaliado. DISCUSSÃO: as células de Muller na retina contém grande quantidade de GSH e podem atuar ativamente na modulação das respostas glutamatérgicas e glicinérgicas; além disso, já foi mostrado que a GSH induz a liberação de GABA na retina, o que pode explicar a diminuição das amplitudes observadas pela super-ativação de alguma via inibitória. CONCLUSÃO: o presente trabalho vem colaborar com a hipótese de que a GSH atue como neuromodulador no SNC, com significativas alterações inibitórias após sua administração na retina.
Glutathione (GSH) is a molecule involved in many biological processes, known primarily for its antioxidant. Currently , this tripeptide composed of glutamate , cysteine and glycine has been widely studied for its possible action as a neurotransmitter in the CNS and nuromodulador . The present study evaluated the action of this molecule through the electroretinogram, to evaluate the mass response of the retina, produced after light stimulation. Methods: GSH intravitreal injections were performed at different concentrations (1 , 5 and 10 mM) and PBS ( control) in Wistar rats. The assessment protocol consisted of 6 stimuli in different conditions of adaptation: Scotopic response of rods and Scotopic maximal response after dark adaptation of at least 12h ; photopic cone response after 10 min of adaptation to the course, with the use of filters subpopulations for the evaluation of UV and S cones , and the response to the stimulus flicker at 12 Hz. The main parameters were the amplitudes of the waves -a and- b and their implicit time, and b-wave amplitude of the flicker. RESULTS: The results show changes in response, with decrease in b-wave amplitude of the ERG in all stimuli . When done the test of multiple comparisons, differences were observed between the control group and 5 mM GSH and 10 mM GSH . Changes in the amplitude of a-wave only observed in Scotopic maximal response, with a significant decrease in the amplitude. The latency time of the responses showed no changes in any individual group. DISCUSSION: The retinal Muller cells contains a large amount of GSH and may act actively in the modulation of glutamate and glycinergic responses, also has been shown that GSH induces the release of GABA in the retina, which may explain the decrease of the amplitudes observed by over- activation of an inhibitory pathway. CONCLUSION: The present work supporting the hypothesis that GSH acts as a neuromodulator in the CNS, with significant inibitory changes in the retina after administration .
Čijauskaitė, Kristina. "Cinko ir selenito jonų įtaka redukuoto glutationo koncentracijai ir lipidų peroksidacijai kadmiu paveiktų laboratorinių pelių kepenyse." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_215121-90540.
Full textIt was determined, that after 8 h cadmium increased glutathione concentration by 35 % while after 14 days decreased by 35 %. After 8 h both zinc and selenium also increased reduced glutathione concentration, respectively, 27 % and 17 %. Evaluating malondialdehyde concentration in mice liver, it was established, that cadmium increased malondialdehyde concentration after 8, 24 h and 14 days, respectively, 336 %, 218 % and 182 %. When mice liver were affected with zinc and selenium, malondialdehyde concentration increased after 24 h, respectively, 325 % and 437 % and after 14 days, respectively, 162 % and 288 %. To sum up, zinc can protect reduced glutathione from oxidation in mice liver just for 8 h, and after a longer period reduced glutathione is depleted. After 8, 24 h and 14 days both, zinc and selenium are eager to protect liver from lipid peroxidation and after 14 days reduced glutathione from oxidation. Lipids from peroxidation process can protect only green tea extract.
Cortés, Troncoso Juan. "Actividad GSH Transferásica Citosólica de Hígado de Rata: Susceptibilidad a Iones Hierro." Tesis, Universidad de Chile, 2007. http://repositorio.uchile.cl/handle/2250/105645.
Full textPreviamente hemos demostrado que el sistema Cu2+/ascorbato puede inhibir la actividad enzimática de algunas proteínas tiólicas a través de dos mecanismos: oxidación inducida por ROS y unión inespecífica de Cu2+ a dichas proteínas. Así por ejemplo, la actividad GSH-transferásica citosólica total fue inhibida por Cu2+ 50 μM ya sea en ausencia o presencia de ascorbato. Al igual que el cobre, el hierro es un metal de transición y sus iones generan ROS a través de las reacciones de Haber Wiess y/o Fenton. Por lo tanto, los iones Fe3+ podrían por un lado oxidar grupos tiólicos de proteínas como también unirse a ellos inespecíficamente, inhibiendo así su actividad biológica. En este trabajo describimos la inhibición de la actividad GSH-transferásica total citosólica de hígado de rata inducida por Fe3+/ascorbato. Esta actividad enzimática fue inhibida por concentraciones micromolares de Fe3+ en presencia de ascorbato, efecto que fue revertido por DTT y cisteína de una forma concentración-respuesta. Este efecto inhibitorio se describe en función de los parámetros cinéticos aparentes de la GST-transferasa. Por otra parte, Fe3+/ascorbato redujo el contenido de tioles microsómicos. Sin embargo, concentraciones micromolares de Fe3+ en ausencia de ascorbato, no alteraron la actividad control de la GSH-transferásica, a pesar de que se ensayaron concentraciones hasta 500 μM. Cabe señalar además, que en nuestras condiciones de ensayo, la capacidad redox de los iones Fe3+ fue menor que la de Cu2+, ya que se necesitaron mayores concentraciones de estos iones para obtener efectos lipoperoxidativos microsómicos similares (Fe3+ 250 μM vs Cu2+ 250 ηM). Los mecanismos que pueden explicar las diferencias observadas entre los iones cobre e hierro, se discuten al final de este manuscrito
We previously reported that Cu2+/ascorbate may change some enzymatic activities of thiol proteins through two mechanisms: ROS-induced oxidation and unspecific Cu2+ binding to it. Thus, total cytosolic GST activity was inhibited by 50 or more μM Cu2+ concentrations in either absence or presence of ascorbate. Similar to copper, iron is also a transition metal and the iron ions also generate ROS through Haber Weiss and/or Fenton reactions. Thus, iron ions may alter the biological activity of thiol proteins through ROS-induced oxidation and also by Fe3+-binding to protein’s thiol groups. The present work describes the inhibition of total cytosolic GST activity from rat liver by Fe3+/ascorbate. Micromolar Fe3+ in the presence of ascorbate inhibited the total cytosolic GST activity, inhibition which was prevented by DTT and cysteine as a concentrationdependent manner. We further described this inhibition effect in terms of GST apparent kinetic parameters. In the similar assay conditions Fe3+/ascorbate reduced the microsomal thiol content. Interestingly, μM Fe3+ in the absence of ascorbate did not affect GST activity, although until 500 μM Fe3+ was used. Moreover, to develop similar microsomal lipoperoxidative effects, a greater iron ions concentration (250 μM Fe3+/ascorbate) than of copper (250 ηM Cu2+/ascorbate) was needed. Finally, we discuss the mechanisms which could explain the differences between copper and iron ions observed
Rabello, Celia Maria de Almeida. "An investigation of the effects of variation in drug metabolism in children with acute lymphoblastic leukaemia undergoing continuing therapy." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308017.
Full textCruzat, Vinicius Fernandes. "Efeito da suplementação com L-glutamina e L-alanil-L-glutamina sobre parâmetros de lesão muscular e de inflamação em ratos treinados e submetidos a exercício intenso de natação." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9132/tde-29012009-185922/.
Full textGlutamine is the most abundant free amino acid found in plasma and muscle, and is utilized at high rates by many cells for maintenance and promotion of cell function. However, in some catabolic situations, like intense and prolonged or exhaustive physical exercise, a reduction in GLN availability is observed, fact that may impair the cell functions. Oral supplementation with dipeptides of glutamine, like L-alanyl-L-glutamine may serve as an interesting way to deliver glutamine to the organism. Male Wistar rats were trained and supplemented with DIP (1,49 g•kg-1) or mixture containing free L-glutamine (1 g•kg-1) and Lalanine (0,61 g•kg-1) or water (CON) and sacrificed in distinct times: before (TR) and immediately after (INT) intense exercise of swim. Plasma and serum concentrations of glucose, GLN, glutamate, ammonia, CK, LDH, TNF-• and PgE2 were evaluated. In muscles (soleus and gastrocnemius) and liver GLN, glutamate, GSH, GSSG and total proteins also were evaluated. Low concentration of CK in plasma was observed in both supplemented groups before the exhaustive test. The DIP-TR presented more concentration of glutamate, GSH e GSH/GSSG in the soleus muscle and liver. Higher concentration of glutamine, glutamate and GSH/GSSG was seen in GLN+ALATR group. Both groups supplemented with DIP and GLN+ALA after the exhaustive test, exhibit decreases in ammonia and TNF-α, and the group DIP-INT, demonstrated decrease in PgE2. Glutamine, glutamate and GSH/GSSG increases in the soleus and glutamate in the gastrocnemius increases in groups DIP-INT and GLN+ALA-INT. Increases in GSH and GSH/GSSG in liver were found in the same groups, compared to CON-INT. Our results indicate that oral supplementation with free L-glutamine added to L-alanine or the dipeptide, Lalanyl-L-glutamine, may influence the muscle and liver stores of GSH and the cellular redox state, and this may attenuate damage and inflammation induced by severe physical exercise.
Loupatatzis, Barbara. "Die CRH-Rezeptor-vermittelte Wirkung von CRH auf das GSH-GSSG-Redoxsystem von Endothelzellen." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-81360.
Full textBrown, Erin. "Modulation of intracellular GSH in THP-1 cells during oxidative stress induced by AAPH." Thesis, University of Canterbury. School of Biological Sciences, 2006. http://hdl.handle.net/10092/2629.
Full textLoupatatzis, Barbara Stefanie. "Die CRH-Rezeptor-vermittelte Wirkung von CRH auf das GSH-GSSG-Redoxsystem von Endothelzellen." kostenfrei, 2007. http://edoc.ub.uni-muenchen.de/8136/.
Full textBurgos, Bravo Francesca. "Efectos pro-oxidantes del complejo Cu(I)-[GSH]2 en su interacción con hierro." Tesis, Universidad de Chile, 2009. http://www.repositorio.uchile.cl/handle/2250/105170.
Full textMCFARLAND, KEVIN LEE. "CHARACTERIZATION OF THE REGULATORY REGION OF THE DISPERSED HOMEOBOX GENE gsh-1." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1022766208.
Full textRajapaksa, Kathila Seuwandhi. "The Role of Ovarian Metabolism in 4-Vinylcyclohexene Metabolites and 7,12-Dimethylbenz[a]anthracene Induced Ovotoxicity in Mice." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194403.
Full textAranda, Ortega Nicolás Alonso. "Efecto de rosuvastatina sobre IL-1BETA, GSH/GSSG y TBARS en ratones con dolor neuropático." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/146977.
Full textIntroduction: Neuropathic pain is caused by injury or dysfunction of the nervous system, one of the most severe that a person can experience. It is produced by pathological changes resulting from a metabolic disease, viral infection, traumatic injury or secondary to chemotherapy. This study evaluated hypernoniceptive behavioral differences and spinal changes of inflammatory and redox state markers in neuropathic mice and how rosuvastatin (RSV) affects those changes. Methods: Neuropathic mice were obtained by partial sciatic nerve ligation (PSNL) and the administration of paclitaxel (PTX). Hypernociception was assessed using the hot plate test, cold plate test and electronic Von Frey test, also, the spinal levels of IL-1β, GSH/GSSG and TBARS was determined, pre and post treatment with RSV. Results: Administration of RSV was able to reverse the mechanical allodynia in acute and chronic injuries, however, it was only able to reverse the chronic thermal hyperalgesia. RSV administration reversed the increase of IL-1β levels in both neuropathy models, in the PSNL model recovered normal levels of GSH/GSSG and in the PTX model was able to reverse the neuronal lipid peroxidation. Conclusion: This study demonstrates the antinociceptive activity of RSV, suggesting that acts by controlling the medullary proinflammatory environment and redox state.
Nordien, Rozeena. "A Decade of Hepatitis C at the UCT/GSH Liver Clinic in the Pre-DAA era." Master's thesis, Faculty of Health Sciences, 2019. http://hdl.handle.net/11427/31175.
Full textBABA, KACEM. "99m technetium-glutathion (99m tc-gsh) caracterisation physico-chimique et biologique in vitro et in vivo." Paris 13, 2000. http://www.theses.fr/2000PA132011.
Full textDavies, Warren Raymond, and warren davies@optusnet com au. "Effects of the Cyanobacterium Nodularia spumigena on Selected Estuarine Fauna." RMIT University. Applied Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080415.164533.
Full textSchiar, Viviane Patrícia Pires. "Avaliação toxicológica de organocalcogênios em eritrócitos humanos." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/4410.
Full textNos últimos anos, os compostos organocalcogênios têm sido alvos de interesse em síntese orgânica em virtude da descoberta de suas aplicações industriais e de suas propriedades farmacológicas. No entanto, dados da literatura têm demonstrado que estes compostos apresentam atividade pró-oxidante ocasionando danos teciduais e inibição da atividade de enzimas. Sabe-se que o estresse oxidativo pode causar alterações em proteínas da membrana de eritrócitos, logo estas células representam um bom modelo para investigar danos induzidos por agentes oxidantes. Desta forma, no presente trabalho investigou-se a toxicidade de uma variedade de calcogênios sobre eritrócitos in vitro nas concentrações de 10, 40, 100 e 200 μM. Os resultados deste trabalho mostraram que para um hematócrito de 45% apenas os compostos de organotelúrio foram tóxicos causando hemólise e estes efeitos não foram correlacionados com a produção de substâncias reativas ao ácido tiobarbitúrico, sugerindo deste modo não haver relação com a peroxidação lipídica. No entanto, utilizou-se um hematócrito de 1% e os compostos de organoselênio e organotelúrio testados apresentaram toxicidade causando hemólise. Esta hemólise foi relacionada com a oxidação da glutationa intracelular (GSH) e uma possível produção de radicais livres. Portanto, os resultados apresentados nesta tese sugerem que os compostos orgânicos contendo selênio ou telúrio apresentaram toxicidade para os eritrócitos.
Camargo, Emmanuel Veiga de. "Atividade de neutrofilos e estresse oxidativo em cordeiros infectados experimentalmente com Haemonchus contortus e suplementados com selênio e vitamina E." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/10062.
Full textThe present work had as its objective to assess the oxidizing metabolism of neutrophils, the complete blood count (CBC) and the oxidizing profile of experimentally infected lambs with Haemonchus contortus and supplemented with selenium and vitamin E. 20 male lambs were used, of the Corriedale breed, distributed in four experimental groups with 5 animals: G1 larvae infected animals and supplemented with 0.2mg/kg living weight (PV) of selenite via intramuscular (IM); G2 larvae infected animals and supplemented with 0.2mg/kg PV of selenite IM and 2000 UI per animal of vitamin E IM; G3 larvae infected animals and supplemented with 2000 UI per animal of E IM; G4 larvae infected animals. For the CBC and the biochemical analysis blood collection on the day zero (T0) were carried out, 20 (T1), 40 (T2) and 60 (T3) through jugular venipuncture using vacutainer® tubes. The weighing and the egg determination by gram of animal feces occurred in the same experimental times. For the NBT tests heparinized blood samples were collected in the days zero, 30, 60. Smaller leukocyte values were detected in the supplemented group exclusively with selenium (G1) in relation to the control group (G4) in time 4. Concerning the lymphocytes it was observed a decrease in the G1 in relation to the supplemented only with vitamin E (G3) and G4 in time 3 (T3). For both the tests, NBT-NE and NBT-E there was a decrease in the dye reduction capacity at 60 days in relation to the other times in the groups treated with selenium (G1 and G2). The result of the oxidizing profile showed a significant elevation in the GSH-Px enzyme in the supplemented groups with selenium. Still, the correlation of Pearson revealed the existence of a negative correlation between the concentrations of GSH-Px and TBARS and between this enzyme and the OPG values. Increments were also observed for the catalase enzyme in animal which received the selenium supplementation or when this element was associated to the vitamin E. Smaller values of lipid peroxidation (TBARS) were detected in supplemented animals when these were compared to the control group. These results suggest that the reduced reserves of this antioxidant may exacerbate the generation of free radicals with an increase of the lipid peroxidation and the increase of the environment contamination by the eggs of Haemonchus contortus. Facing these results it is possible to conclude that the selenium supplementation provides a larger protection to the cell antioxidant and to the organism as a whole in lambs experimentally infected by Haemonchus contortus.
O presente trabalho teve como objetivo avaliar o metabolismo oxidativo dos neutrófilos, o hemograma e o perfil oxidativo de cordeiros experimentalmente infectados com Haemonchus contortus e suplementados com selênio e vitamina E. Foram utilizados 20 cordeiros machos, da raça Corriedale, distribuídos em quatro grupos experimentais com 5 animais: G1- animais infectados com larvas e suplementados com 0,2mg/kg de peso vivo (PV) de selenito de sódio por via intramuscular (IM); G2- animais infectados com larvas e suplementados com 0,2mg/kg PV de selenito de sódio IM e 2000 UI por animal de Vitamina E IM; G3- animais infectados com larvas e suplementados com 2000 UI por animal de Vitamina E IM; G4-animais infectados com larvas. Todos os grupos foram infectados, pela via oral, com 500 larvas L3 de Haemonchus contortus por animal a cada dois dias, pelo período de vinte dias a partir do dia zero. Para o hemograma e as análises bioquímicas foram realizadas coletas de sangue nos dias zero (T0), 20 (T1), 40 (T2) e 60 (T3) por venopunção da jugular utilizando-se tubos vacutainer®. As pesagens e a determinação dos ovos por grama de fezes dos animais ocorreram nesses mesmos tempos experimentais. Para as provas de NBT foram coletadas amostras de sangue heparinizadas nos dias zero, 30 e 60. Menores valores de leucócitos totais foram detectados no grupo suplementado exclusivamente com selênio (G1) em relação ao grupo controle (G4) no tempo 4. Em relação aos linfócitos observou-se diminuição no G1 em relação ao suplementado somente com vitamina E (G3) e G4 no tempo 3 (T3). Para ambos os testes, NBT-NE e NBT-E houve uma diminuição da capacidade de redução do corante aos 60 dias em relação aos demais tempos nos grupos tratados com selênio (G1 e G2).Os resultados do perfil oxidativo demonstraram significativa elevação da atividade da enzima GSH-Px nos grupos suplementados com selênio. Ainda, a correlação de Pearson revelou a existência de correlação negativa entre as concentrações de GSH-Px e TBARS e entre esta enzima e os valores de OPG. Incrementos também foram observados para a enzima catalase nos animais que receberam suplementação com selênio ou quando este elemento foi associado a vitamina E. Menores valores de lipoperoxidação lipídica (TBARS) foram detectados nos animais suplementados quando estes foram comparados ao grupo controle. Esses resultados sugerem que as reservas diminutas deste antioxidante podem exacerbar a geração de radicais livres com um aumento da peroxidação lipídica e o aumento da contaminação ambiental pelos ovos de Haemonchus contortus. Diante dos resultados é possível concluir que a suplementação com selênio proporciona uma maior proteção antioxidante celular e ao organismo como um todo de cordeiros experimentalmente infectados pelo Haemonchus contortus.
Lúcio, Cristina de Fatima. "Efeito da glutationa reduzida (GSH) na criopreservação de espermatozóides da espécie canina: avaliação in vitro e in vivo." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-25072012-180831/.
Full textThe present experiment aimed to compare the addition of different concentrations of reduced glutathione (GSH) on frozen-thawed canine semen, considering the morphofunctional characteristics; and to verify the pregnancy rate and number of puppies per litter obtained from intrauterine insemination by endoscopic catheterization of the cervix, with frozen-thawed semen containing different concentrations of glutathione. During the first phase of the experiment, two seminal samples collected weekly from 11 mature dogs were used. Three different concentrations of reduced glutathione (0, 10 and 20 mM) were supplemented in a tris-citrate egg yolk extender. The fresh, chilled, glycerolized and post-thawed semen were assessed by flow cytometry using specific probes to determine plasma membrane and acrosomal integrity, mitochondrial membrane potential and DNA fragmentation. Thiobarbituric acid reactive substances (TBARS) assay was also performed to assess the occurrence of oxidative stress. In the second phase of the experiment, six canine females were allocated into two groups: intrauterine insemination with frozen-thawed semen containing 10 mM GSH (IA-GSH10, n = 3) and without the addition of glutathione (IA-GSH0, n = 3). Bitches were monitored by vaginal cytology, vaginoscopy, progesterone and LH assays. Two inseminations were performed on days 5 and 6 post LH peak. We verified that the addition of 10 and 20 mM of GSH to semen extender promoted a decrease in post-thaw sperm motility, as well as a higher damage degree at the 20 mM concentration. We also detected a higher percentage of acrossomal integrity in treated groups. At glycerolization and moreover, the sperm exposure to liquid nitrogen and further thawing, were responsible for the decrease in sperm motility, due to the loss of mitochondrial function through the free radicals production. Gestation was diagnosed in two female from IA-GSH10 group and two bitches of the IA-GSH0 group. In conclusion, we did not observe the expected protective effects of the addition of 10 and 20 mM GSH to semen extender. Furthermore, the concentration of 20 mM was responsible for the more extreme damage to semen sample. The supplementation of 10 mM GSH to semen extender for cryopreservation maintained the fertility rates similar to the ones observed for cryopreservation without antioxidant supplementation in dogs.
Souza, Luiz Felipe de. "Modulação redox de peroxirredoxinas e a participação dos sistemas da GSH e da Trx na proteção/função celular." reponame:Repositório Institucional da UFSC, 2017. https://repositorio.ufsc.br/xmlui/handle/123456789/182600.
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Tióis celulares estão entre os principais alvos das espécies reativas de oxigênio (ERO), portanto, estão no centro dos processos redox celulares. A oxidação de tióis proteicos pode levar à perda de função de enzimas, modulação de vias de sinalização e morte celular; assim, a manutenção do estado redox destes tióis é crucial para a homeostasia celular. Os sistemas da glutationa (GSH) e da tiorredoxina (Trx) são considerados os principais tampões redox celulares e são os principais sistemas envolvidos na manutenção do estado redox celular. A contínua reciclagem das formas oxidadas da GSH e Trx pelas enzimas glutationa redutase (GR) e tiorredoxina retudase (TrxR) é crucial para este processo, mantendo o contínuo fluxo de elétrons para peroxidases. A glutationa peroxidase (GPx) e as peroxirredoxinas (Prx) estão entre as peroxidases mais eficientes. As Prx são consideradas sensores de H2O2, participando de vias de sinalização redox, sendo o estado de oxidação de sua cisteína catalítica um marcador de estresse oxidativo. A perda da homeostasia redox tem sido correlacionada com diversas situações patológicas, como inflamação e câncer. Dessa forma, o presente trabalho tem como objetivo analisar a importância dos sistemas da GSH e Trx na proteção de células contra oxidantes, além de estudar a modulação redox das Prx durante a fagocitose em neutrófilos. No primeiro trabalho investigamos o efeito de 2-acetylamino-3-[4-(2-acetylamino-2- carboxyethylsulfanylthiocarbonylamino)phenylthiocarbamoylsulfanyl] propionic acid (2-AAPA), um inibidor da GR, sobre parâmetros de viabilidade celular e balanço redox em células derivadas de glioblastoma humano A172. Nossos dados demonstram que o 2-AAPA, além de inibir a GR, também é um potente inibidor da TrxR. A inibição dessas enzimas por 2-AAPA diminuiu drasticamente a capacidade dessas células em metabolizar peróxidos orgânicos, deixando as células mais vulneráveis a este peróxido. 2-AAPA apresentou um perfil de toxicidade tempo- e concentração-dependente. A oxidação da Prx 1, Prx2 e Prx3 foi observada apenas na concentração tóxica de 100µM, após 30 min de incubação. 2-AAPA também causou uma severa disfunção mitocondrial, afetando o potencial de membrana e respiração acoplada a produção de ATP. Apresentamos evidências de que a oxidação de peroxirredoxinas e disfunção mitocondrial são eventos precoces na toxicidade de 2-AAPA a células A172. Coletivamente, esses dados reforçam a hipótese do papel central dos sistemas da GSH e Trx na proteção de células a agentes oxidantes, e reforça a hipótese de que a inibição conjunta de GR e TrxR pode ser uma estratégia interessante para o tratamento de câncer. No segundo trabalho, estudamos a modulação redox de Prx durante o burst oxidativo em células pró-mielocíticas HL60 diferenciadas em neutrófilos. Demonstramos que a diferenciação dessas células com DMSO diminui a expressão da Prx2 de uma maneira tempo dependente, mas não alterou os níveis de Prx1, indicando um possível papel regulatório da Prx2 na diferenciação dessas células por DMSO. Enquanto isso, a diferenciação com ATRA não alterou os níveis de Prx2. A estimulação das células diferenciadas com forbol miristato acetato ou staphylococcus aureus induziu o burst oxiativo nas células diferenciadas, levando à oxidação da Prx1 de uma maneira tempo-dependente. A oxidação da Prx1 foi dependente da atividade da NADPH oxidase, já que a sua inibição aboliu esse efeito. Além disso, demonstramos que a inibição da NADPH oxidase por Diphenyleneiodonium chloride diminui a oxidação basal da Prx1. Por último, discutimos os resultados apresentados com dados obtidos em neutrófilos durante a minha estadia no Center for Free Radical Research da Nova Zelândia, sob orientação da Christine Winterbourn. Mostramos que as Prx estão completamente oxidadas em condições basais, um fenômeno nunca antes observado. Assim, apresentamos dados relevantes que podem ter implicações importantes para a sinalização redox e, consequentemente, para a função de células inflamatórias. De modo geral, os dados apresentados ressaltam a importância da modulação do ambiente redox na função e morte celular.
Abstract : Thiol groups are amongst the main targets of reactive oxygen species (ERO), therefore they are at the center of all redox processes in the cell. Protein thiol oxidation can lead to loss of function, response signaling and cell death and, hence, the maintenance of thiols in cell is critical for cellular homeostasis. The glutathione (GSH) and thioredoxin (Trx) systems are the main redox buffers in cells. The continuous recycling of the oxidized forms of GSH and Trx is achieved by the action of glutathione reductase (GR) and thioredoxin reductase (TrxR), which keep the constant supply of electrons for the peroxidases. Among these, the peroxiredoxins (Prx) have a special role, acting as a peroxide sensor and marker of oxidative stress. The loss of redox homeostasis has been linked to several pathologies such as inflammation and cancer. Therefore, this work aims at study the importance of the GSH and Trx systems to cell protection against oxidants, and to analyze the redox modulation of Prx during inflammatory processes. In the first work, we investigated the effect of 2-acetylamino-3-[4-(2-acetylamino-2- carboxyethylsulfanylthiocarbonylamino)phenylthiocarbamoylsulfanyl]propionic acid (2-AAPA), an inhibitor of GR and TrxR, on parameters of cell viability and redox balance in A172 glioblastoma cells. The inhibition of these enzymes drastically reduced cell?s capacity to metabolized organic peroxides (but not H2O2) and, consequently, rendered cells more susceptible to organic peroxide. 2-AAPA also displayed a time and concentration dependent toxicity. We observed a marked oxidation of Prx 1, 2 and 3, as well as a severe mitochondrial dysfunction. Collectively, our results highlight the importance of GSH and Trx systems to cell?s protection against oxidants. Also, we present evidence that oxidation of Prx and mitochondrial dysfunction are early events in 2-AAPA toxicity to A172 cells. In the second work, we studied the redox modulation of Prx during oxidative burst in differentiated promyelocytic HL60 cells. We demonstrated that the differentiation of these cells to a neutrophil-like phenotype with dimethylsulfoxide (DMSO) greatlydiminished Prx2 expression in a time-dependent manner, but didn´t change Prx1 expression. Pharmacological stimulation or exposure to microbes induced the oxidative burst in the differentiated cells, leading to Prx1 oxidation in a time-dependent manner. Oxidation of Prx1 was dependent on NADPH oxidase, because inhibition of this enzyme abolished this effect. Furthermore, inhibition of the oxidase by Diphenyleneiodonium chloride reduced the basal oxidation of Prx1 in unstimulated cells. Lastly, we discuss the presented results with data obtained from human neutrophils during my stay at the Center for Free Radical Research in New Zealand under supervision of Christine Winterbourn. We show for the first time that the Prx are completely oxidized under unstimulated conditions. Therefore, the presented results may have important implications for the role of Prx in inflammatory cells function. Overall, this thesis highlights the central role of the modulation of the redox environment to cell function and death, as well as shows, for the first time, a Prx fully oxidized in unstressed conditions.
Urdaneta, Vargas Aixa Efrailda. "Utilización de compuestos tiol en la producción in vitro de embriones a partir de ovocitos de cabras prepúberes." Doctoral thesis, Universitat Autònoma de Barcelona, 2005. http://hdl.handle.net/10803/5659.
Full textWith the aim of trying to improve in vitro embryo production (IVEP) from prepubertal goat oocytes, three studies were designed in this investigation. The objetive of first study was to assess, in oocytes selected by the brillant cresyl blue (BCB) test, the effect of the addition to in vitro culture (IVC) medium of either glutathione (GSH) alone or GSH in combination with glucose on the embryo development. Oocytes were exposed to BCB and were classified as: oocytes with a blue cytoplasm (BCB+) and oocytes without blue cytoplasm (BCB-). BCB+ oocytes showed higher percentage of nuclear maturation than the BCB- and control group (82.6%, 55.7% and 74.7%, respectively). The percentage of polyspermic oocytes was higher in BCB- than BCB+ oocytes. Supplementation of in vitro culture (IVC) medium with 1mM de GSH did not affect embryo development, but the porcentage of total embryos developed after culture was higher in BCB+ oocytes than in BCB- oocytes independently of the GSH supplementation. The addition of glucose, alone or with GSH, did not affect embryo development. The aim of the second study was to evaluate the effect of adding different concentrations (100μM, 200μM and 400 μM) of cyteamine to the IVM medium and to the in vitro embryo culture (IVC) medium (50 μM or 100 μM) on the embryo development of prepubertal goat oocytes BCB-selected. The addition of 400 μM cysteamine to the IVM improved normal fertilisation and embryo development of BCB- oocytes at the same rates as those obtained from BCB+ oocytes. The proportions of morulae plus blastocyst development were not affects by the treatments. Finally, was studied the effect of adding cysteamine (400 μM) to IVM medium, glutathione (1mM) to IVF medium and ionomycin to the sperm capacitation medium. This treatment improved normal fertilisation, zygotes with male pronucleus and embryo development of prepubertal goat oocytes, however did not improve blastocyst development.
Filho, Josà Delano Barreto Marinho. "ParticipaÃÃo das vias atm/atr e c-myc/gsh nos efeitos antitumorais da cordiaquinona J induzidos pelo estresse oxidativo." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8697.
Full textAs cordiaquinonas sÃo naftoquinonas meroterpenÃides isolados de plantas pertencentes ao gÃnero Cordia com vÃrias atividades biolÃgicas descritas, incluindo atividades antifÃngica, larvicida e citotÃxica. O objetivo deste trabalho foi avaliar o potencial anticÃncer de uma cordiaquinona isolada das raÃzes da planta Cordia leucocephala. O presente estudo avaliou o potencial citotÃxico da cordiaquinona J em vÃrias linhagens de cÃlulas tumorais e normais pelo teste do MTT e seu possÃvel mecanismo de aÃÃo. A cordiaquinona J mostrou valores de CI50 variando de 4,6 a 6,8 μM em cÃlulas leucÃmicas e 33,6 a 37 μM em cÃlulas normais, apÃs 24 horas de incubaÃÃo. Nas cÃlulas HL-60 foi observado induÃÃo de apoptose preferencialmente pela via extrÃnseca. A induÃÃo do dano ao DNA observado pelo tratamento com a cordiaquinona J atravÃs do ensaio do cometa foi associado com a ativaÃÃo de proteÃnas quinases da via ATM/ATR. O dano ao DNA, assim como a ativaÃÃo das proteÃnas quinases da via ATM/ATR foi visualizado em cÃlulas HL-60, mas nÃo em cÃlulas normais. Estes efeitos em HL-60 podem estar relacionados com a depleÃÃo da expressÃo proteica de glutationa e de c-myc observados. O potencial anticÃncer foi confirmado in vivo atravÃs da inibiÃÃo do tumor sarcoma-180 em 72,5% apÃs o tratamento com 50 mg/kg de cordiaquinona J. O prÃ-tratamento tanto das cÃlulas quanto dos animais com N-acetil-L-cisteina inibiu todos os efeitos observados in vitro e in vivo reforÃando o papel da geraÃÃo das espÃcies reativas de oxigÃnio na atividade antitumoral da cordiaquinona J.
Cordiaquinones are meroterpenoid naphtoquinones from plants belonging to the genus Cordia with several described biological activities, including antifungal, larvicidal and cytotoxic effects. The aim of this study was to evaluate the anticancer potential of a cordiaquinone isolated from the roots of Cordia leucocephala plant. The present study evaluated the cytotoxic potential of cordiaquinone J in several tumor and normal cell lines by MTT assay and its possible mechanism of action. The study of the mechanism of action of cordiaquinones L and M, in human leukemia cells (HL-60) showed induction of cell death by apoptosis, and these effects were related to the induction of oxidative stress. Then the study was continued only with the cordiaquinone J. The cordiaquinone J showed IC50 values ranging from 4.6 to 6.8μM in leukemia cells and 33.6 to 37 μM in normal cells, after 24 hours of incubation. In HL-60 cells was observed apoptosis induction preferentially by extrinsic pathway. The induction of DNA damage by cordiaquinone J observed by comet assay was associated with activation of protein kinases of ATM/ATR pathway. The DNA damage, as well as activation of protein kinases via the ATM / ATR was observed in HL-60 cells but not in normal cells. These effects in HL-60 cells may be related to the depletion of protein expression of glutathione and c-myc observed. The anticancer potential was confirmed in vivo through inhibition of sarcoma-180 tumor by 72.5% after the treatment with 50 mg/kg of cordiaquinone J. The pre-treatment of cells or animals with N-acetyl-L-cysteine abolished most of the in vitro and in vivo observed effects, reinforcing the role of reactive oxygen species generation in cordiaquinone J activity.
Silva, Renata Sofia Araújo da. "Desenvolvimento de uma metodologia de HPLC para a detecção de aductos das catecolaminas com a GSH em amostras biológicas." Master's thesis, Universidade de Aveiro, 2006. http://hdl.handle.net/10773/712.
Full textIntrodução: Níveis elevados de catecolaminas circulantes podem conduzir a fenómenos de cardiotoxicidade e neurotoxicidade. A cardiotoxicidade pode surgir devido à sobrestimulação de receptores adrenérgicos embora existam evidências crescentes que apontam para um papel importante da oxidação das catecolaminas na ocorrência destes efeitos tóxicos. Também os efeitos neurotóxicos induzidos pela dopamina e pelos seus produtos de oxidação foram já considerados como intervenientes importantes na patofisiologia da doença de Parkinson. Estudos mecanísticos in vitro corroboram estas observações demonstrando que os produtos de oxidação das catecolaminas podem, posteriormente, sofrer conjugação com a GSH em cardiomiócitos e hepatócitos isolados de rato, resultando na formação de espécies de elevada toxicidade. A identificação e quantificação destas espécies reactivas em amostras biológicas é, deste modo, de extrema importância. Objectivo e Métodos: Desenvolver uma metodologia de cromatografia líquida de alta resolução (HPLC) para a detecção de aductos das catecolaminas biogénicas, adrenalina, noradrenalina e dopamina, com a GSH em amostras biológicas. Para a síntese dos aductos foram efectuadas misturas reaccionais em soro humano contendo cada uma das catecolaminas em estudo (3,3 nM até 3,75 mM), tirosinase e GSH. Após 12 minutos de reacção, os aductos foram extraídos mediante adsorção na alumina. Foram injectadas alíquotas dos extractos obtidos num sistema de HPLC equipado com um detector de fotodíodos e um detector coulométrico. Foram utilizadas uma coluna Spherisorb S5 ODS2 e uma fase móvel eluída em modo isocrático, a fluxo de 1 mL/min, e constituída por metanol (2 a 10%, dependendo da catecolamina), ácido cítrico (50 mM) e ácido octanossulfónico (0,46 mM) com pH ajustado a 3,0. Os aductos mono- e bi-conjugados das catecolaminas com a GSH foram caracterizados de acordo com os seus espectros no ultravioleta. A posterior análise destes aductos por espectrometria de massa sustentou a sua identidade. Após a optimização das condições para a detecção e extracção destes compostos, foi validado o método para a detecção de aductos da adrenalina (ADR) com a GSH em amostras de soro humano. Resultados/Discussão: Foi desenvolvida uma metodologia de HPLC em modo isocrático e em fase reversa com detecção por fotodíodos e/ou coulométrica, de forma a analisar os aductos de catecolaminas biogénicas com a GSH. Foi igualmente desenvolvido um procedimento de tratamento das amostras de soro humano para análise destes aductos. O método demonstrou possuir uma boa precisão [boa repetibilidade instrumental (CV <3%), boa repetibilidade do procedimento global (CV <5%) e boa precisão intermédia (CV <6%)]. Foi obtida uma resposta linear para concentrações de adrenalina entre 0 e 175 μM. O limite de detecção foi grandemente melhorado pelo processo de extracção (2 pmol e 0,066 pmol de ADR para o primeiro e segundo monoconjugado, respectivamente), enquadrando-se dentro dos níveis esperados de catecolaminas em determinadas condições patofisiológicas. As recuperações da extracção foram diferentes para os dois monoconjugados da ADR com a GSH (entre 51 e 93%, dependendo do aducto e da concentração de ADR testada). Em conclusão, o desenvolvimento desta metodologia permite a análise directa de aductos da adrenalina com a GSH em soro humano, demonstrando ser uma importante ferramenta analítica para o estudo do processo de oxidação das catecolaminas e da toxicidade associada a estes compostos. ABSTRACT: Introduction: Sustained high levels of circulating catecholamines may lead to cardiotoxicity and neurotoxicity. Cardiotoxicity can occur via adrenoceptor overstimulation although increasing evidence also points toward an important role of the catecholamines oxidation in the induction of these toxic effects. Furthermore, neurotoxic effects induced by dopamine and its oxidation products are considered to be important factors contributing to the pathogenesis of Parkinson’s disease. Mechanistic in vitro studies corroborate these findings since they have shown that the catecholamines oxidation products can further conjugate with GSH in isolated rat cardiomyocytes and hepatocytes leading to the formation of highly toxic species. The identification and quantification of these reactive species in biological samples is, thus, of utmost importance. Aim and Methods: To develop an high performance liquid chromatography (HPLC) methodology for detection of GSH adducts of the biogenic catecholamines adrenaline, noradrenaline, and dopamine in biological samples. For the synthesis of the adducts reaction mixtures were made in human serum containing each catecholamine (3.3 nM up to 3.75 mM), tyrosinase and GSH. After 12 min of reaction, the adducts were extracted after adsorption to alumina. Aliquots of these extracts were injected into an HPLC system equipped with a photodiode array detector and a coulochem detector. A Spherisorb S5 ODS2 column and an isocratic mobile phase consisting of methanol (2 up to 10%, depending on the catecholamine), citric acid (50 mM) and octanesulfonic acid (0.46 mM) adjusted to pH 3.0 at a 1 mL/min flow rate were used. The mono- and bi-conjugates of catecholamines with GSH were characterized by their UV spectra. Further analysis by mass spectrometry of these adducts sustained their identity. After the optimization of all the conditions for the detection and extraction of these compounds, the method was validated for the detection of adrenaline (ADR) GSH adducts in human serum. Results and Discussion: An isocratic reverse-phase HPLC method with photodiode array and/or coulochem detection was developed in order to analyse biogenic catecholamines-GSH adducts. A sample treatment procedure for analysis of these adducts in biological samples was also developed and applied to human serum. The method showed good precision [good instrumental repeatability (<3% CV), good overall procedure repeatability (<5% CV), and good intermediate precision (< 6% CV)]. A linear response was obtained for adrenaline concentrations of 0 to 175 μM. The limit of detection was greatly improved by the extraction process (2 pmol and 0.066 pmol for the 1st and 2nd mono GSH conjugates, respectively) falling into the expected catecholamine levels occurring in certain pathophysiological conditions. The extraction recoveries were different for both adrenaline-GSH monoconjugates (between 51 and 93%, depending on the adduct and on the tested adrenaline concentration). In conclusion, the development of this method allows the direct analysis of GSH adducts of adrenaline in human serum, providing a valuable tool for the study of the catecholamines oxidation process and the toxicity associated with these compounds.
Marinho, Filho José Delano Barreto. "Participação das vias atm/atr e c-myc/gsh nos efeitos antitumorais da cordiaquinona J induzidos pelo estresse oxidativo." reponame:Repositório Institucional da UFC, 2012. http://www.repositorio.ufc.br/handle/riufc/5557.
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Cordiaquinones are meroterpenoid naphtoquinones from plants belonging to the genus Cordia with several described biological activities, including antifungal, larvicidal and cytotoxic effects. The aim of this study was to evaluate the anticancer potential of a cordiaquinone isolated from the roots of Cordia leucocephala plant. The present study evaluated the cytotoxic potential of cordiaquinone J in several tumor and normal cell lines by MTT assay and its possible mechanism of action. The study of the mechanism of action of cordiaquinones L and M, in human leukemia cells (HL-60) showed induction of cell death by apoptosis, and these effects were related to the induction of oxidative stress. Then the study was continued only with the cordiaquinone J. The cordiaquinone J showed IC50 values ranging from 4.6 to 6.8μM in leukemia cells and 33.6 to 37 μM in normal cells, after 24 hours of incubation. In HL-60 cells was observed apoptosis induction preferentially by extrinsic pathway. The induction of DNA damage by cordiaquinone J observed by comet assay was associated with activation of protein kinases of ATM/ATR pathway. The DNA damage, as well as activation of protein kinases via the ATM / ATR was observed in HL-60 cells but not in normal cells. These effects in HL-60 cells may be related to the depletion of protein expression of glutathione and c-myc observed. The anticancer potential was confirmed in vivo through inhibition of sarcoma-180 tumor by 72.5% after the treatment with 50 mg/kg of cordiaquinone J. The pre-treatment of cells or animals with N-acetyl-L-cysteine abolished most of the in vitro and in vivo observed effects, reinforcing the role of reactive oxygen species generation in cordiaquinone J activity.
As cordiaquinonas são naftoquinonas meroterpenóides isolados de plantas pertencentes ao gênero Cordia com várias atividades biológicas descritas, incluindo atividades antifúngica, larvicida e citotóxica. O objetivo deste trabalho foi avaliar o potencial anticâncer de uma cordiaquinona isolada das raízes da planta Cordia leucocephala. O presente estudo avaliou o potencial citotóxico da cordiaquinona J em várias linhagens de células tumorais e normais pelo teste do MTT e seu possível mecanismo de ação. A cordiaquinona J mostrou valores de CI50 variando de 4,6 a 6,8 μM em células leucêmicas e 33,6 a 37 μM em células normais, após 24 horas de incubação. Nas células HL-60 foi observado indução de apoptose preferencialmente pela via extrínseca. A indução do dano ao DNA observado pelo tratamento com a cordiaquinona J através do ensaio do cometa foi associado com a ativação de proteínas quinases da via ATM/ATR. O dano ao DNA, assim como a ativação das proteínas quinases da via ATM/ATR foi visualizado em células HL-60, mas não em células normais. Estes efeitos em HL-60 podem estar relacionados com a depleção da expressão proteica de glutationa e de c-myc observados. O potencial anticâncer foi confirmado in vivo através da inibição do tumor sarcoma-180 em 72,5% após o tratamento com 50 mg/kg de cordiaquinona J. O pré-tratamento tanto das células quanto dos animais com N-acetil-L-cisteina inibiu todos os efeitos observados in vitro e in vivo reforçando o papel da geração das espécies reativas de oxigênio na atividade antitumoral da cordiaquinona J.
Melis, Nicolas. "Identification de deux nouvelles cibles dans la gestion du stress oxydatif ; la protéine CFTR et la voie d’activation d’eIF5A." Thesis, Nice, 2015. http://www.theses.fr/2015NICE4030.
Full textOxidative stress represents a particular cellular condition, characterized by an intracellular increase in thereactive species level. These species are highly reactive towards biomolecules and result of oxygenconsumption by biological systems essentially through respiration. Deregulation of the cellular oxidativestate can initiate adaptive processes (as elevation adaptation) or several human pathologies (stroke,infarct). This thesis work has been devoted to the study of two news potential targets allowing atolerance/resistance towards disequilibrium of oxidative stress; the first one is CFTR, a channel protein(«Cystic Fibrosis Transmembrane conductance Regulator»), and the second one is the activation pathwayof the translation factor eIF5A («eukaryotic Initiation translation Factor 5A»). Based on the peculiaractivity of CFTR, consisting in the transport of glutathione, the major antioxidant of the cell, weevidenced the role of CFTR in the management of cellular oxidative state during cytotoxic drugexposure (cisplatin) or during adaptation to chronical hypoxia. The second target, eIF5A is the only oneprotein described as post-translationally modified by fixation of a hypusine residue. We demonstratedthat inhibition of eiF5A activation protect cells from reactive oxygen species generated during anoxia. Atcellular level, this protection is accompanied with deep metabolic and mitochondrial changes. Usinganimal models, we showed that inhibition of this eiF5A activation allows a tolerance against ischemicaccident in different organs (kidney and brain). These fundamentals results can have extensiveapplication in human clinical use (infarct, stroke, graft)
Cunha, Gina Michelle Mac?do da. "Altera??es nas concentra??es das SRAT, conte?do de GSH e atividade da CAT em pacientes com esquistossomose aguda." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13435.
Full textSchistosomiasis is an ancient disease caused by helminth Schistosoma mansoni and is a public health problem in Brazil. The granulomatous lesion, typical of the disease, associates itself with increase in the oxidative damage through the generation of free radicals. The aim of this work was to evaluate the occurrence of changes in parameters oxidant / antioxidant that are part of the human defense system, and observe whether they would cause oxidative stress in subjects with schistosomiasis. Moreover, correlating with some biochemical and hematological parameters. Two groups were selected for study, consisting of individuals of both sexes, aged between 16 and 30 years. A control group, formed by individuals without schistosomiasis (n = 30) and a test group, formed by individuals with schistosomiasis (n = 30). The evaluation of lipid peroxidation in plasma was performed by determination of malondialdehyde and antioxidant defense by the quantification of reduced glutathione and catalase activity. For the parameters that assess oxidative stress, the results showed a decrease in the content of reduced glutathione and no change in the activity of catalase, with an increase in the value of malondialdehyde. Therefore, the data found suggest the occurrence of oxidative stress in subjects with schistosomiasis. Of the parameters that assess hepatic function, only levels of aspartate aminotransferase have been high, while there was a decrease of bilirubine. There was a significant change in the lipid profile (p <0.5), however with regard to the renal function of patients, there was a decrease in creatinine. The assessment hematological, made through hemogram and the quantification of hemoglobin, shows increase of eosinophils individuals in the group test, which can be related to the presence of the parasite. The amendments suggest the involvement of oxidative stress in the pathophysiology of this disease
A esquistossomose ? uma doen?a milenar causada pelo helminto Schistosoma mansoni e constitui um problema de sa?de p?blica no Brasil. A les?o granulomatosa, t?pica da doen?a, est? associada com o aumento do dano oxidativo atrav?s da gera??o de radicais livres. O objetivo deste trabalho foi avaliar a ocorr?ncia de altera??es nos par?metros oxidante/antioxidante que fazem parte do sistema de defesa do organismo, e observar se os mesmos provocariam estresse oxidativo em indiv?duos com esquistossomose. Al?m disso, correlacionando com alguns par?metros bioqu?micos e hematol?gicos. Foram selecionados dois grupos de estudo, constitu?dos de indiv?duos de ambos os sexos, com faixa et?ria compreendida entre 16 e 30 anos. Um grupo controle, formado por indiv?duos sem esquistossomose (n=30) e um grupo teste, formado por indiv?duos com esquistossomose (n=30). A avalia??o da peroxida??o lip?dica no plasma foi realizada por meio da determina??o do malondialde?do e a defesa antioxidante pela dosagem da glutationa reduzida e determina??o da atividade da catalase. Em rela??o aos par?metros que avaliam o estresse oxidativo, os resultados demonstraram uma diminui??o do conte?do de glutationa reduzida e nenhuma altera??o na atividade da catalase, com um aumento nos valores de malondialde?do. Portanto, os dados encontrados sugerem a ocorr?ncia do estresse oxidativo nos indiv?duos com esquistossomose. Dos par?metros que avaliam a fun??o hep?tica, apenas os n?veis de aspartato amino transferase mostraram-se elevados, enquanto ocorreu uma diminui??o da bilirrubina. N?o houve uma altera??o significativa no perfil lip?dico (p<0.5), entretanto com rela??o ? fun??o renal dos pacientes, houve uma diminui??o da creatinina. A avalia??o hematol?gica, realizada atrav?s do hemograma completo e a dosagem da hemoglobina, mostra eosinofilia nos indiv?duos do grupo teste, que pode estar relacionada com a presen?a do parasita. As altera??es apresentadas sugerem a participa??o do estresse oxidativo na fisiopatologia da referida doen?a
Aljoumaa, Khaled. "Synthèse et caractérisations d'une nouvelle famille de copolymères fluorés pour l'optique non linéaire quadratique." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2008. http://tel.archives-ouvertes.fr/tel-00341976.
Full textWang, Yanmei. "THE THIOL REDOX SYSTEM IN OXLDL-INDUCED MACROPHAGE INJURY." UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/383.
Full textDinescu, Adriana. "Modeling wild type and mutant glutathione synthetase." Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc5556/.
Full textRimbault, Daniel. "Implementation of Hadamard Encoding and Reconstruction of MEGA-Edited Spectroscopy (HERMES) for quantification of ɣ-aminobutyric acid (GABA) and glutathione (GSH)." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/33012.
Full textFarida, Siti. "Influence de l'environnement (exercice et nutrition) durant la gestation sur l’état de stress oxydant et le métabolisme du glucose de la descendance." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAV049/document.
Full textInfluence de l'environnement (exercice et nutrition) durant la gestation sur l’état de stress oxydant et le métabolisme du glucose de la descendance.Les maladies métaboliques sont en pleine expansion dans nos sociétés actuelles et constituent un enjeu de santé publique majeur. Les antécédents familiaux, l'environnement et les habitudes de vie de l'individu vont jouer un rôle dans la susceptibilité à certains de ces désordres métaboliques. Sur la base de données épidémiologiques, un lien a été établi entre environnement durant les premières phases de la vie et survenue de pathologies à l'âge adulte conduisant au concept des "Developmental Origins of Health and Diseases" (DOHaD). Le premier objectif de ce travail était d'étudier, à partir d'un modèle murin, les conséquences de l'exercice physique quotidien de la mère pendant la gestation sur la composition corporelle, le statut oxydant, la fonction pancréatique et mitochondriale du foie et du muscle et la gestion des substrats énergétiques de la descendance. Un deuxième objectif était de valider un modèle de diabète gestationnel à partir d’un régime riche en fructose et d’étudier l’effet d’une supplémentation en fer durant ce diabète gestationnel sur le statut oxydant et la tolérance au glucose des mères et de la descendance. Nos résultats montrent une réduction significative de la production mitochondriale d’H2O2, un indicateur de la production d’espèces réactives de l’oxygène, dans le foie et dans le muscle des petits de mères entrainées. Ces changements sont reliés à des altérations de la consommation d’oxygène mitochondriale, de la composition des membranes mitochondriales et de l’activité des enzymes antioxydantes. De plus, l'entraînement maternel avant et pendant la gestation est associé à des modifications de la structure et de la fonction du pancréas de la descendance et semble modifier sa gestion des substrats énergétiques.Nous avons également confirmé qu’une diète riche en fructose durant la gestation peut être utilisée comme un modèle induisant un diabète gestationnel. Nous avons ainsi démontré chez les petits nés de mères nourries avec un régime riche en fructose et en fer, que les activités des enzymes antioxydantes comme la glutathion peroxidase (GPx), la glutathion-S-transferase dans le foie et la GPx dans le cerveau étaient altérées, les résultats étant différents selon le sexe des petits. Les différents résultats obtenus chez la descendance montrent que dans le cas d’un diabète gestationnel, les fœtus sont plus sensibles que leurs mères aux effets d’un régime riche en fer. Ce travail de thèse vient compléter les travaux menés dans le cadre des DOHaD et renforce l'idée que l'environnement lors des premières phases de la vie va avoir des conséquences sur la santé de l'individu.Mots-clés : exercice, gestation, descendance, mitochondries, stress oxydant, diabète gestationnel, fer, régime riche en fructose
CRISTOFANON, SILVIA. "Pathways of survival to oxidative stress: competition between Bcl-2 and Bax and role of NF-kappaB." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2008. http://hdl.handle.net/2108/583.
Full textLewis, Catrin. "Phase I development of a guided self help (GSH) programme for the treatment of mild to moderate post traumatic stress disorder (PTSD)." Thesis, Cardiff University, 2011. http://orca.cf.ac.uk/54210/.
Full textCearfoss, Jacquelyn M. "The Induction of Oxidative Stress in the Livers of Mice Following Long-Term Exposure to the Water Chlorination By-Products, Dichloroacetate and Trichloroacetate." University of Toledo Health Science Campus / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=mco1333652434.
Full textBenlloch, García María. "Depleción de GSH y Bcl-2 en células de melanoma maligno B16: mecanismos de sensibilización frente al estrés oxidativo/nitrosativo y la quimioterapia." Doctoral thesis, Universitat de València, 2008. http://hdl.handle.net/10803/9911.
Full textIntroduction:The main cause of death from cancer is due to metastases. Malignant melanoma cell subsets show different degrees of multidrug and radiation resistance. Analysis of a Bcl-2 family of genes revealed that B16 melanoma (B16M)-F10 cells (high metastatic potential) have overexpressed preferentially Bcl-2 ( 5.7-fold). B16M-F10 cells show high GSH content and a decrease in GSH efflux.Mitochondria do not synthesize GSH. Mitochondrial GSH (mtGSH) depletion facilitates permeability transition pore complex (PTPC) opening, and the release of apoptosis-inducing molecular signals. In previous studies in Ehrlich ascites tumor cells was found that L-glutamate (L-Glu) derived from L-Gln competitively inhibited GSH transport into mitochondria, depleting selectively tumor mtGSH. Results:We found that GSH release from B16M-F10 cells is channeled through the multidrug resistance protein 1 (MRP1) and the cystic fibrosis transmembrane conductance regulator (CFTR). Bcl-2 inhibits the release of GSH through CFTR facilitating accumulation of GSH within the metastatic cells.Parallel to the Bcl-2-sensitive CFTR, the transport of GSH by MRP1 can carry out by means of a verapamil (VRP)-dependent active transport. We investigate the combination of VRP with a Bcl-2 antisense phosphorothioate-derivatized oligodeoxynucleotides (bcl-2-AS). bcl-2-AS and VRP increased the GSH efflux. Intracellular GSH content decreased in bcl-2-AS- and VRP-treated B16M-F10 cells. However, at 12 h of perifusion time, GSH levels were ~70% higher. These results showed that the loss of GSH content acelerated its intracellular synthesis. tumor -GT activity and an intertissue flow of GSH increase GSH content in B16M-F10 cells. We tested if adding an irreversible -GT inhibitor (acivicin, ACV) we could decrease GSH synthesis. With bcl-2-AS, VRP and ACV treatment, GSH synthesis was similar to control values whereas the GSH efflux increased. We can combinate this selective GSH depletion therapy with non toxic dosis of TNF- and L-Gln enriched diets (GED). So, we investigated a combination of GED, TNF- and bcl-2-AS and found that viability of B16M decreased up to 88% respect control values. The increased of TNF--induced ROS and bcl-2-AS treatment afected superoxide dismutase (SOD) activity. Treating B16Mcells with a double anti- antisense therapy (Bcl-2- and SOD2-AS) and TNF- , metastatic cell survival decreased to 1%. Chemotherapy easily removed this minimum percentage of highly resistant metastatic survivors.
Souza, Antonio Albuquerque de. "Estudos eletroquímicos do 2-[p-nitrofenil (hidroxi) metil] acrilato de metila: um fármaco antitumoral e sua reatividade frente a GSH, dsDNA e oxigênio." Universidade Federal de Alagoas, 2007. http://repositorio.ufal.br/handle/riufal/1092.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior
No presente trabalho, foram realizados estudos eletroquímicos de compostos que apresentam expressiva atividade antiproliferativa, conhecidos como adutos de Baylis-Hillman. As técnicas utilizadas foram: voltametria cíclica, de pulso diferencial e de onda quadrada e eletrólise a potencial controlado. Os estudos eletroquímicos revelaram um comportamento padrão para o composto nitroaromático 2-[p-nitrofenil(hidroxi)] acrilato de metila (2). Em meio aprótico (DMF + TBAP, 0,1 mol L-1), o composto 2 apresentou três ondas de redução, sendo as duas primeiras referentes à redução do grupo nitro e, assim como no composto padrão não nitrado, 2-[fenil(hidroxi)] acrilato de metila (1), a onda adicional, em potencial mais negativo, relaciona-se à redução do grupo acrilato. Em meio prótico, tampão fosfato pH 6,9, uma única onda catódica relativa à formação da hidroxilamina é observada. Nos estudos em meio aquoso alcalino (EtOH + fosfato, DMF + fosfato ou EtOH + bicarbonato de sódio + NaOH, pH ~ 9), observou-se a formação de intermediário radicalar estável, o ânion radical nitro. Eletrólises em potencial controlado, em meio prótico neutro, levaram à formação e isolamento de um dímero, após redução do grupo nitro, em processo de 4e-/4 H+. Estudos eletroquímicos realizados em biossensor de dsDNA, sugerem que um dos alvos para ação biológica de 2 é o DNA. A lesão ao DNA, refletida pela presença de picos diagnósticos de oxidação das bases guanina e adenina, mensuráveis eletroquimicamente, é observada apenas após redução do grupo nitro (farmacóforo) a intermediários reativos, reforçando a necessidade de biorredução do grupo para posterior atividade biológica. Os estudos eletroquímicos e espectrofotométricos, em presença de GSH e GSSG, revelaram que os produtos de redução do grupo nitro interagem com os endobióticos, de maneira diferente. Para o meio fosfato + NaOH, pH 9,4, a adição de GSH promoveu o aumento na intensidade de corrente para o primeiro processo eletródico, bem como a perda de reversibilidade. Já a segunda onda de redução, relativa à formação da hidroxilamina, não foi observada no voltamograma. De acordo com as funções ácidas da GSH, aliada ao ineficiente efeito tamponante desse meio, a glutationa atua como doador de prótons, favorecendo a formação do derivado nitroso. Por outro lado, em tampão bicarbonato + NaOH, onde se tem um eficiente efeito tamponante e a glutationa se encontra na forma desprotonada, as alterações voltamétricas são mais discretas, com aumento da reversibilidade do processo referente à formação do ânion radical nitro. Em potenciais mais negativos, a onda relativa à geração da hidroxilamina desaparece, o que evidencia a interação de GSH com os produtos de redução estendida do grupo nitro. A possibilidade de catálise, em presença de oxigênio, não foi evidenciada para 2. Os resultados obtidos fornecem subsídios úteis para a compreensão do mecanismo de ação antitumoral de 2, que pode ser considerado um agente biorredutivo, com função adicional seqüestradora de glutationa
BOVIO, FEDERICA. "The cadmium altered oxidative homeostasis leads to energetic metabolism rearrangement, Nrf2 activation with increased GSH production and reduced SOD1 activity in neural cells." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/309982.
Full textThe heavy metal cadmium is a widespread toxic pollutant, released into the environment mainly by anthropogenic activities. Human exposure can occur through different sources: occupationally or environmentally, with its uptake through inhalation of polluted air, cigarette smoking or ingestion of contaminated food and water. It mainly enters the human body through the respiratory and the gastrointestinal tract and it accumulates in liver and kidneys. Brain is also a target of cadmium toxicity, since this toxicant may enter the central nervous system by increasing blood brain barrier permeability or through the olfactory nerves. In fact, cadmium exposure has been related to impaired functions of the nervous system and to neurodegenerative diseases, like amyotrophic lateral sclerosis (ALS). ALS is a fatal motor neuron pathology with the 90-95% of ALS cases being sporadic (sALS), while the remaining 5-10% of familial onset (fALS); among fALS, the 15-20% is attributed to mutations in superoxide dismutase 1 (SOD1). SOD1 is an antioxidant protein responsible for superoxide anions disruption and it is a homodimeric metalloenzyme of 32 kDa mainly located in the cytoplasm, with each monomer binding one catalytic copper ion and one structural zinc ion within a disulfide bonded conformer. Since oxidative stress is one of the major mechanisms of cadmium induced toxicity and an alteration of oxidative homeostasis, through depletion of antioxidant defences, is responsible for a plethora of adverse outcoming mainly leading to cell death; we focused on cadmium effect (1) on the energetic metabolism in human neuroblastoma SH-SY5Y cell line, (2) on the oxidative defences responses in differentiated human LUHMES neural cell line and (3) on the function of human SOD1 in a three models approach (recombinant protein in E. coli, in SH-SY5Y cell line and in the nematode Caenorhabditis elegans). The evaluation of energetic metabolism of SH-SY5Y neural cells treated with sub-lethal CdCl2 doses for 24 hours, showed an increase in glycolysis compared to control. This shift to anaerobic metabolism has been confirmed by both glycolytic parameters and greater ATP production from glycolysis than oxidative phosphorylation, index of less mitochondrial functionality in cadmium treated cells. Regarding the fuel oxidation cadmium caused an increase in glutamine dependency and a specular reduction in the fatty acids one, without altering the glucose dependency. Moreover, we observed an increase in total GSH, in the GSSG/GSH ratio and in lipid peroxidation, all index of an altered oxidative homeostasis better investigated in LUHMES cells. In this model a 24h cadmium administration enhanced the total GSH content at the lower doses, at which also activates Nrf2 through a better protein stabilization via p21 and P-Akt. The metal adverse effects on cell viability can be rescued by GSH addition and by cadmium treatment in astrocytes- or microglia-conditioned medium. In the latter cases the total GSH level remains comparable to untreated cells even at higher CdCl2 concentrations. Finally, SOD1 catalytical activity has been investigated in the presence of cadmium. The first evaluation of this metal combined with fixed copper and/or zinc on the recombinant GST-SOD1, expressed in E. coli BL21, showed a dose-dependent reduction in SOD1 activity only when copper is added to cellular medium, while the expression remains always constant. Similar results were obtained in SH-SY5Y cell line, in which SOD1 enzymatic activity decreased in a dose- and time-dependent way after cadmium treatment for 24 and 48 hours, without altering its expression; as well as in the Caenorhabditis elegans model, where a 16 hours cadmium treatment caused a 25% reduction only in SOD1 activity. In conclusion, cadmium caused a shift to anaerobiosis, a Nrf2 activation, with increased GSH production, and a reduction in SOD1 activity.
Wang, Yingsong. "Investigating the In Vitro Oxidative Folding Pathways of Bovine Pancreatic Trypsin Inhibitor (BPTI)." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/1029.
Full textDagdeviren, Melih. "The Investigation Of Srebp And C/ebp Expression During Global Ischemia/reperfusion Induced Oxidative Stress In Rat Brain Cortex And Cerebellum." Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12611157/index.pdf.
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(C/EBP&
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), glutathione (GSH), malondialdehyde (MDA), glutathione-S-transferase (GST), and superoxide dismutase (SOD). Carotid artery occlusion (CAO) plus hypotension was produced for 10 minutes. Control groups were sham operated. Animals were sacrificed after 24 hours, 1 week, 2 and 4 weeks of reperfusion periods. The expression of C/EBP&
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and SREBP-1 in rat brain cortex and cerebellum were examined by western blotting. C/EBP&
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expressions significantly increased in both cytosolic (1.19, 1.58 fold) and nuclear (1.73, 1.81 fold) extracts of brain cortex at 24 hours and 1 week CAO groups, respectively. In cerebellum, C/EBP&
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expression significantly increased in 1 week, cytosolic (1.63 fold), and nuclear (1.35 fold) extracts. SREBP-1 expression increased significantly in both cytosolic (2.07 fold) and nuclear (1.41 fold) extracts of brain cortex in 1 week. SREBP-1 expression significantly increased in cytosolic (2.15 fold) and nuclear (1.79 fold) extracts of cerebellum in 1 week. There were no significant alterations in SREBP-1 C/EBP&
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expressions for 2 and 4 weeks in both cytosolic and nuclear extracts of brain cortex and cerebellum. There were insignificant changes in GSH and GST levels in cortex. However, MDA and SOD levels significantly increased by 43.0 % and 47.3 %, respectively, in 24 hours. Our findings indicate that increase in SREBP-1 and C/EBP&
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expressions may be related to oxidative stress during ischemic neurodegenerative processes.
Cruz, Késia de Souza. "Otimização numérica da produção de glutationa por saccharomyces cerevisiae utilizando subprodutos industriais." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6204.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Recent studies show that often, pathologies are caused by Reactive oxygen species (ROS). The ROS are associated with the oxidative stress in the cells. The body uses the antioxidants to defend itself from the consequences of this process. An example of an antioxidant with different functions in an organism is the Glutathione (GSH). It is a cellular thiol with low molecular mass, that’s synthesized by chemical, enzymatic and fermentative methods. Since it is environmentally and economically viable, the use of the fermentative process has gained scientific visibility. The use of mathematical models is an alternative that helps in the production of Glutathione. Considering these observations, the present study's aimed to elaborate a mathematical model for production and prediction of GSH for Saccharomyces cerevisiae, as well as to validate its numerical optimization experimentally. For the mathematical model in this process, was used the Central Composite Rotational Design 2², having as an answer, the GSH and biomass values in function with the concentration of molasses and glycerol during a period of 96 hours of fermentation. Based on these results, a hybrid model was made, having as a result, the specific rate of GSH formation. The final model was adjusted to a polynomial function using the method of least squares. Experimentally, the maximum production of GSH was found to be, in 72 hours (119,6 mg L-1) using 76,9 g L-1of molasses and glycerol, respectively. Applying the model for similar conditions, it was estimated to a 118,6mg L-1. The experimental results were then statistically analyzed to verify their similarity. The numerical optimization was made by setting the clock for 72 hours. At this step, the concentration of molasses and glycerol were varied until the best conditions to produce GSH were met. The optimization helped to derive an estimate that 70 g L-1of sugar cane molasses and 40 g L-1of glycerol can guarantee the production of 126 mg L-1of GSH. Based on the accuracy of the observations, the same conditions were used as a central point for the validation of the model - Factorial Design2². The results obtained under these conditions helped establish that the central point of the proposed design for the validation of the model, is 127,3mg L-1of GSH in 72 hours. The validation of this mathematical model by the numerical optimization proved that it was effective for the production and prediction of Glutathione by Saccharomyces cerevisiae, using industrial by-products.
Estudos recentes mostram que as patologias mediadas por espécies reativas de oxigênio (ERO) estão frequentes. As EROs associam-se ao estresse oxidativo nas células, e para o corpo defender-se das consequências advindas desse processo, utiliza os antioxidantes. Um exemplo de antioxidante com variadas funções no organismo é a glutationa (GSH). Trata-se de um tiol celular de baixa massa molecular, que pode ser sintetizada por via química, enzimática e fermentativa. Devido sua viabilidade ambiental e econômica, o uso de processos fermentativos tem ganhado visibilidade científica. O emprego de modelos matemáticos é uma alternativa que auxilia na predição deste antioxidante. Tendo em vista estas observações o presente trabalho teve como objetivo elaborar um modelo matemático de predição da produção de GSH por S. cerevisiae, bem como validar experimentalmente sua otimização numérica. Para a confecção do modelo matemático utilizou-se um Delineamento Composto Central Rotacional 2², tendo como resposta os valores de GSH e biomassa em função das concentrações de melaço e glicerol durante 96 horas de fermentação. A partir desses resultados foi confeccionado um modelo híbrido, tendo como resposta a velocidade específica de formação de GSH. O modelo final foi ajustado a uma função polinomial utilizando metodologia dos Mínimos Quadrados. Experimentalmente a máxima produção de GSH foi encontrada em 72 horas (119,6 mg L-1) utilizando 76,9 g L-1 de melaço e glicerol, respectivamente. Aplicando o modelo para as mesmas condições estimou-se 118,6 mg L-1. Os resultados experimentais e preditos foram analisados estatisticamente para verificar a similaridade dos mesmos. A otimização numérica foi feita fixando o tempo em 72 horas. Nessa etapa variaram-se as concentrações de melaço e glicerol até obter a melhor condição para produzir GSH. A otimização estimou que 70 g L-1de melaço de cana-de-açúcar e 40 g L-1 de glicerol podem garantir uma produção de 126 mg L-1 de GSH. Tendo em conta esta constatação, essas condições foram utilizadas como ponto central de um Delineamento Fatorial Completo 2² para validação do modelo. O resultado encontrado nas mesmas condições do ponto central do delineamento proposto para validação foi de 127,3 mg L-1 de GSH em 72 horas. A validação do modelo matemático por meio de otimização numérica comprovou que o uso da modelagem foi eficaz para a predição da produção de glutationa por Saccharomyces cerevisiae utilizando subprodutos industriais.
Rojas, Sepúlveda Daniel Alberto. "Efecto de un extracto de episperma del grano de Chenopodium quinoa Willd. (Quínoa) sobre la actividad de las isoformas de la GSH-transferasa hepática de rata." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/111280.
Full textLas plantas contienen además de polifenoles, compuestos tiólicos; entre ellos, GSH y cisteína, principales responsables de los mecanismos antioxidantes no-enzimáticos en células animales. No existen en la literatura estudios acerca de la capacidad redox de extractos herbales que poseen concentraciones significativas de compuestos tiólicos. En este trabajo, hemos realizado un estudio preliminar con un extracto de episperma del grano Chenopodium quinoa Willd (quínoa), el cual fue titulado respecto de su contenido en polifenoles y tioles. La razón polifenoles totales versus tioles totales de este extracto fue 9,3. Como una forma de probar la capacidad redox reversible que se asigna a los tioles, usamos como sistema biológico las isoformas citosólicas y microsómica de la GSH-transferasa de hígado de rata, dado que la forma activa de estas isoformas es un dímero -S-S-. El extracto herbal inhibió ambas actividades enzimáticas de una forma concentración dependiente. Más aún, el poder reductor de dicho extracto mostró ser significativamente mayor que los agentes reductores N-acetil-cisteína, ditiotreitol y catequina. Los cambios en las constantes cinéticas aparentes obtenidas indicarían que el extracto herbal provoca un desbalance redox en los componentes de ambas fracciones subcelulares, siendo esta la causa principal involucrada en la inhibición de las actividades GSH-transferásicas observada. Nuevos experimentos están siendo llevados a cabo con el objeto de evaluar diferentes preparados herbales conteniendo tioles que puedan ser utilizados en futuras preparaciones nutracéuticas y/o fitofarmacéuticas.
The main responsible of the non-enzymatic antioxidant mechanisms of plants and animals are thiol compounds and plants contain beside polyphenols. Thiol compounds are represented main by GSH and cysteine. Studies of antioxidant properties of herbal extracts which have significant concentrations of thiol compounds are scarce. Thus, in this work, we have done a preliminary study with an extract of Chenopodium quinoa Willd (quinoa) coats, which was titrated in its polyphenols and thiol content. The ratio between polyphenols versus thiols in this extract was 9.3. As a manner to test the reversible redox capacity assigned to thiols, we use, as a biological system, rat liver cytosolic and microsomal isoforms of the GSH-transferase, because the enzymatic active form of this enzyme is its disulfide dimeric form. The quinoa extract inhibited both enzymatic activities in a concentration-dependent manner. Furthermore, the reducing power of this extract proved to be significantly higher than other reducing agents like N-acetyl-cysteine, dithiothreitol or catechin. The changes on the apparent kinetics constants obtained would indicate that the quinoa extract causes a redox imbalance in the components of both subcellular fractions, being this the main reason involved in the inhibition of GSH-transferase activities observed. New experiments are being carried out in order to evaluate different herbal preparations containing thiols which may be used in future nutraceutical and/or phytopharmaceutical preparations
Díaz, García Víctor Manuel. "Desarrollo de una herramienta para el seguimiento de metástasis temprana in vivo en ratones C57BL/6 usando células B16F10 marcadas con QDs-GSH biomimético de CdTe." Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/165755.
Full textActualmente, la metástasis es la principal causa de muerte de pacientes con cáncer. Su estudio sigue siendo en gran medida una "caja negra" debido a la incapacidad para rastrear células malignas a medida que colonizan los órganos diana. Por lo tanto, el conocimiento sobre los primeros pasos durante la metástasis in vivo sigue siendo limitado Muchos estudios han propuesto el uso de nanopartículas semiconductoras fluorescentes o puntos cuánticos (QDs) como un nuevo medio para marcar células y tumores. Sin embargo, las aplicaciones de los QDs están limitadas por su toxicidad en sistemas biológicos y lo poco que se sabe sobre su capacidad de afectar la metástasis de las células cancerosas. Previamente, describimos la síntesis "biomimética" de QDs de Cadmio-Teluro hidrófilos (QDs-GSH) con una mayor biocompatibilidad en comparación a otros QDs de cadmio producidos por distintos medios. Además, esta metodología nos permitió obtener células de cáncer gástrico MKN45 marcadas con estos QDs-GSH. Sin embargo, aún se desconoce como la presencia de los QDs-GSH en el interior de las células podrían afectar la capacidad metastásicas de células tumorales. Por estos motivos, este estudio planteó generar una metodología que permita obtener células de melanoma murino B16F10 marcadas con QDs-GSH en su interior, con el propósito de ser utilizadas en estudios de metástasis temprana. Se evaluó diferentes metodologías para incorporar QDs-GSH en células de melanoma murino B16F10 y que además permitieran disminuir los efectos tóxicos después de dicha incorporación en las células. Luego, se caracterizó el efecto sobre la capacidad metastásica in vitro e in vivo de la incorporación de QDs-GSH en células B16F10. Más tarde, se desarrolló una metodología para obtener células B16F10 marcadas con QDs-GSH (células marcadas casi 100% viables), las cuales migran de forma similar a las células control y permanecen viables por al menos cinco días. Sin embargo, la proliferación, la invasión y la capacidad de formar nódulos metastásicos en los pulmones se atenuaron severamente por la incorporación de QDs. Los resultados mostraron que las células B16F10 marcadas con QDs-GSH pueden usarse para rastrear la distribución/acumulación temprana de estas células en diferentes órganos de ratones C57BL/6 usando el sistema de imágenes in vivo (IVIS). Además, revelaron que estas células se distribuyen en, corazón, pulmones, riñones e hígado de ratones C57BL/6 a los cinco minutos de la inyección intravenosa, para posteriormente acumularse en los pulmones. Adicionalmente, en este estudio se realizó una prueba de concepto (utilizando células B16F10 marcadas con QDs que sobreexpresan Cavelolina-1), que permitió evaluar el potencial de utilizar esta metodología de marcaje celular como una herramienta útil para caracterizar la acumulación/distribución temprana de células B16F10 en ratones C57BL/6. Esto, permitiría evaluar los efectos de fármacos y/o diferentes factores biológicos sobre el proceso de acumulación/distribución temprana de células metastásicas. En conjunto, esto permitiría mejorar la comprensión de estos eventos tempranos en la metástasis y posiblemente actuar sobre ellos
Currently, metastasis is the leading cause of death in cancer patients. Our understanding of this process remains limited largely due to the inability to track malignant cells as they colonize the target organs. Therefore, an improved understanding of the first steps during in vivo metastasis is highly desirable. Many studies have proposed the use of fluorescent semiconductor nanoparticles or quantum dots (QDs) as a new tool for labeling cells and tumors. However, the applications of QDs in this field are limited by their toxicity in biological systems along with the lack of knowledge of the effects that QDs might have on the metastatic capacity of cancer cells. Previously, we described the "biomimetic" synthesis of hydrophilic CdTe-QDs (QDs-GSH) with increased biocompatibility compared to the cadmium QDs that had been evaluated until then, together with a methodology that allowed us to obtain MKN45 gastric cancer cells labeled with QDs-GSH. However, it remained unclear how the presence of the QDs-GSH inside the cells could affect the metastatic capacity of tumor cells. For these reasons, we sought to develop here a methodology that permitted obtaining B16F10 murine melanoma cells labeled in their interior with QDs-GSH, which have the potential to be used in studies of early metastasis. To that end, this study evaluated different methodologies to incorporate QDs-GSH in murine melanoma B16F10 cells and to diminish the toxic effects following such incorporation into cells. Then, the effect on metastatic capacity in vitro and in vivo of the incorporation of QDs-GSH in B16F10 cells was characterized. Subsequently, a methodology was developed that allowed us to obtain QDs-GSH-labeled B16F10 cells (nearly 100% viable labeled cells), which remained viable for at least five days and migrated similarly to control cells. The results showed that QDs-GSH-labeled B16F10 cells can be used to track the early distribution / accumulation of these cells in different organs of C57BL / 6 mice using in vivo imaging system (IVIS) and revealed that these cells were detected as soon as five minutes after intravenous injection in the heart, lungs, kidneys and liver, and subsequently accumulated in the lungs of C57BL / 6 mice. However, proliferation, invasion and the capacity to form metastatic nodules in the lungs of such QDs-GSH-labeled B16F10 cells were severely attenuated. Also, in this study a proof of concept experiment was included using B16F10 cells labeled with QDs that overexpress Cavelolin-1. These experiments showed that Caveolin-1 expression favors very early accumulation of B16F10 cells in the lung and in doing so revelaed the potential of this cell labeling approach as a useful tool to characterize the early accumulation / distribution of B16F10 cells in C57BL/6 mice. Also, similar experiments should allow us in the future to evaluate the effects of drugs and / or different biological factors on the process of early accumulation / distribution of metastatic cells. These experiments will allow us to improve our understanding of the early events leading to metastasis and possibly modulate the outcome
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BALDELLI, SARA. "Ruolo dell'ossido nitrico sintasi neuronale (nNOS) nella modulazione dell'omeostasi redox intracellulare." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2009. http://hdl.handle.net/2108/861.
Full textNitric oxide (NO) plays an important role in both physiological and pathophysiological mechanisms involving properties at the chemical, cellular, and physiological levels. The relatively low concentration of NO required being an antioxidant suggests that in addition to its involvement with cyclic GMP, this radical molecule serves to counterbalance oxidative stress. This balance between NO and oxidative stress provides an important regulatory mechanism in numerous physiological effects. Imbalance in this redox symbiotic relationship can lead to different pathophysiological conditions. Here we demonstrate the neuroprotective role played by nNOS/NO in counteracting the ROS-mediate ciotoxicity, induced by treatment with garlic derivatives. In particular, we found that, besides their role in promoting growth arrest and apoptosis, either oil-soluble derivatives DADS or water GE significantly increased the content of nNOS in neuronal cell lines. Next to the antioxidant action of NO, each cell is equipped with an extensive antioxidant system to counteract their harmful properties directly by interception or indirectly through reversal of oxidative damage. In central nervous system, the antioxidant defence system and nNOS may interact to ensure the integrity and homeostasis of neuronal cells. Especially in the nervous system the nNOS/NO may directly or indirectly modulate the activity and expression of antioxidant defence systems. Indeed, we further analysed the influence of endogenous overproduction on NO on the intracellular antioxidants SOD1 and GSH in cell lines of neuronal and non-neuronal origin. We report that nNOS over-expression induced a NO-dependent increase in the concentration of GSH thus reinforcing the idea that it represents a protective agent against NO cytotoxicity. On the other hand, the nNOS over-expression causes a NO-indipendent down-regulation of SOD1 in terms of mRNA, protein and activity levels.
Zaragoza, Colom Rosa. "Cambios en la expresión de los genes involucrados en el ciclo celular y apoptosis durante el destete en la glándula mamaria de rata lactante. Papel del GSH." Doctoral thesis, Universitat de València, 2004. http://hdl.handle.net/10803/9520.
Full textIn the lactating mammary gland, weaning produces mitochondrial cytochrome c release and nuclear DNA fragmentation. This is followed by a significant decrease in milk production and the decline of lactation. Weaning for 2h produces an early induction of p53, whereas c-Jun and JNK are elevated after 24h of weaning. The expression of p21cip1 and p27kip1, both cyclin-dependent kinase inhibitors, is significantly higher in weaned rats when compared to control lactating rats. All the changes mentioned above also happen in the lactating mammary gland when PPG, an inhibitor of the liver trans-sulfuration pathway, is administered. This effect is partially reversed by N-acetylcysteine (NAC) administration. The administration of buthionine sulfoximine (BSO), an irreversible inhibitor of -glutamyl cysteine synthetase, to lactating rats produces a decrease in GSH levels and changes in protein levels and gene transcripts similar to the rats with impaired trans-sulfuration pathway. These data suggest that the intertissue flux of glutathione is an important mechanism of L-cysteine delivery to the lactating mammary gland and emphasizes the importance of this physiological event to maintain gene expression required to keep lactation.Once characterized the apoptosis in the mammary gland we used this model to study "in vivo" the role of nitric oxide during cell death. The three isoforms of the nitric oxide synthase (NOS) are constitutively present in the acini of the lactating mammary gland. The amount of iNOS and NO production are increased during weaning when compared to control lactating glands, but the protein levels of the eNOS isoform are diminished. Western blot analysis demonstrated that protein nitration was increased in the weaned mammary gland, althought limited to a few specific tyrosine-nitrated proteins. A decrease of GSH in the mammary tissue at the peak of lactation partially mimics these findings and emphasizes the role of NO as a potential signal that triggers involution.
CICCONE, SARAH. "Studio dei polimorfismi delle glutatione trasferasi nell'aumentata suscettibilità ai processi tumorali: caratterizzazione strutturale e funzionale della glutatione trasferasi di cianobatterio." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2010. http://hdl.handle.net/2108/1219.
Full textGlutathione S-transferases (GSTS) are considered part of a coordinated defence strategy, together with other GSH-dependent enzymes, the cytochrome P450s (Phase I enzymes) and some membrane transporters (Phase III) such as MRP1 and MRP2, to remove from the cell the products of oxidative stress generated after interaction of reactive oxygen species, that escape the first line of defense, with cellular macromolecules such as DNA, lipids and proteins. Glutathione S-transferases (EC 2.5.1.18) catalyze the conjugation of glutathione (GSH) with a variety of toxic compounds (carcinogens, anticancer drugs, reactive oxygen species and products of cellular metabolism) that contain an electrophilic atom, i.e. carbon, nitrogen or sulphur. In mammals, there are three major families of proteins that exhibit glutathione transferase activity: two of these, the cytosolic and mitochondrial GSTs, comprise soluble enzymes, while the third family are microsomal (MAPEG) and are referred to as membrane-associated proteins in eicosanoid and glutathione metabolism (Hayes et al., 2005). The human cytosolic GSTs are dimeric proteins; each subunit contains a very similar binding site for GSH (G-site) and a second one for the hydrophobic co-substrate (H-site). Structural differences at the H-site confer a certain degree of substrate selectivity. The human cytosolic GSTs can be grouped into at least seven gene-independent classes on the basis of their amino acid sequence and immunological properties: Alpha, Mu, Pi, Sigma, Theta, Omega, and Zeta Cytosolic GSTs display polymorphisms in humans, and this is likely to contribute to interindividual differences in responses to xenobiotics . A lot of studies suggest that that combinations of polymorphisms in Mu, Pi, and Theta class GST contribute to diseases development. In the first part of this work we analyzed three common polymorphisms in the GSTP1, GSTT1, and GSTM1 genes either decrease or abolish GST enzyme activity: the GSTP1 allelic variants, that differ at either a single codon position (Ile104 (HGSTP1*A), Val104 (HGSTP1*B), Val113 HGSTP1*D) or at two different positions (Val104/Val113 (HGSTP1*C)), and the homozygous deletions of the GSTT1 or GSTM1 gene that lead to an absence of enzymatic activity. The commonly used anti-cancer drug chlorambucil is the primary treatment for patients with chronic lymphocytic leukaemia. Chlorambucil has been shown to be detoxified by human glutathione transferase Pi (GST P1-1), an enzyme that is often found over-expressed in cancer tissues. The allelic variants of GST P1-1 are associated with differing susceptibilities to leukaemia and differ markedly in their efficiency in catalysing glutathione (GSH) conjugation reactions. Here, we perform detailed kinetic studies of the allelic variants with the aid of three representative co-substrates. We show that the differing catalytic properties of the variants are highly substrate-dependent. We show also that all variants exhibit the same temperature stability in the range 10 °C to 55 °C. We have determined the crystal structures of GST P1-1 in complex with chlorambucil and its GSH conjugate for two of these allelic variants that have different residues at positions 104 and 113. Chlorambucil is found to bind in a non-productive mode to the substrate-binding site (H-site) in the absence of GSH. This result suggests that under certain stress conditions where GSH levels are low, GST P1-1 can inactivate the drug by sequestering it from the surrounding medium. However, in the presence of GSH, chlorambucil binds in the H-site in a productive mode and undergoes a conjugation reaction with GSH present in the crystal. The crystal structure of the GSH–chlorambucil complex bound to the *C variant is identical with the *A variant ruling out the hypothesis that primary structure differences between the variants cause structural changes at the active site. Finally, we show that chlorambucil is a very poor inhibitor of the enzyme in contrast to ethacrynic acid, which binds to the enzyme in a similar fashion but can act as both substrate and inhibitor. In another part of this work we determined in the peripheral blood lymphocytes of 157 workers exposed to benzene, using 25 individuals not exposed as external controls, the presence of polymorphic genes GSTT1 and GSTM1 and the distribution of GSTP1 allelic variants. We have also evaluated the glutathione transferases (GST) activities and the levels of glutathionylated hemoglobin in the RBC of the same samples. Because this study is in progress again, we can’t estabilish the finals conclusions. During my Phd project I have also analyzed the presence of GSTP1-1 enzyme in prostatic cancer cells lines. In contrast to frequent overexpression of GST-pi observed in many types of cancer, the vast majority of primary human prostate tumors contain no detectable GST pi. So, this enzyme is abundant in normal prostate basal epithelial cells, but basal cells are lost during development of invasive cancer. Absence of GST pi expression in human prostate cancer is accompanied by hypermethylation of regulatory sequences within the GST pi gene, whereas no such hypermethylation is present in normal tissues or benign prostatic hyperplasia (HPB). So we employed Western blot analysis and specific activity assays to measure GST pi expression in diferrents prostatic cancer cells lines selected on the basis of their tumor staging. We have analyzed HBP lines (positive controls), G1 cells lines (associated with a negative prognosis), G2 cells lines (associated with good prognosis) and LNCaP (negative controls). At the and of this study we observed that the most relevant expression of GST pi was detectable in HPB cells, but also in G2 and G1 cells is possible to note a very low presence of this enzyme. The last part of my project comprehend the purification and the enzymatic caratherization of a new GST, called GST short, sequenzed by the cyanobacteria Synechocystis sp PCC 6803 genome. Cyanobacteria represent a group of widely distributed prokaryotes performing oxygenic photosynthesis similar to plants. This, together with their generally accepted role as progenitors of plant plastids, and their ease of genetic manipulation, has made them extremely useful in studies of environmental gene regulations and the mechanism of oxygenic photosynthesis. In according to its phylogenetic origin, GST short presents a very similar G-site sequence with the sequence previously described for GSTI and GSTIII of Zea mays. It is also active towards several classical substrates, but at the same moderate rates that have been observed for other glutathione transferases derived from prokaryotes. Particulary, it was possible observe a strong perossidase activity. We have also analyzed the GST short thermal stability respect to hGSTP1-1 (10°-55°C) and the results indicate that the cyanobacterial enzyme is less resistant at this temperatures than human enzyme probably because its different structure. The cloning, expression and characterization of this cyanobacterial glutathione transferase is also described . The possible significance of the observed catalytic properties is discussed in the context of structural organization and glutathione transferase evolution.