Dissertations / Theses on the topic 'Antioxidant defences'
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Rickett, Guy Masami Wilson. "Perinatal development of pulmonary antioxidant defences." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316750.
Full textGrundy, Jean Elizabeth Carleton University Dissertation Chemistry. "Antioxidant defences during estivation in the spadefoot toad Scaphiopus couchi." Ottawa, 1996.
Find full textNelson, Michelle Amy, and n/a. "Protein Bound 3,4-Dihydroxyphenylalanine as a Signal for Enhanced Antioxidant Defences." University of Canberra. n/a, 2008. http://erl.canberra.edu.au./public/adt-AUC20081209.125208.
Full textNelson, Michelle Amy. "Protein bound 3,4 dihydroxyphenyalanine as a signal for enhanced antioxidant defences /." full text via ADT, 2008. http://erl.canberra.edu.au/public/adt-AUC20081209.125208/index.html.
Full textMubarak, Bashayer Rashed A. "Control of anti-apoptotic and antioxidant pathways in neural cells." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8057.
Full textAucoin, Richard R. "Antioxidants and antioxidant enzymes as biochemical defenses against phototoxin ingestion by insect herbivores." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7679.
Full textCardona, Emilie. "Influence de l'environnement trophique de l'élevage en biofloc sur les performances physiologiques de la crevette Litopenaeus stylirostris : Étude de paramètres de la nutrition, de l'immunité et de la reproduction." Thesis, Nouvelle Calédonie, 2015. http://www.theses.fr/2015NCAL0001/document.
Full textBiofloc is an intensive rearing system with zero or minimal water exchange where a diverse population of microorganisms (microalgae, zooplankton and bacteria) develops in association with organic matter to form the floc particles. These particles play the double role of biological filter and dietary supplement. This dissertation aims to better understand the process of this rearing system and its interactions with the Litopenaeus stylirostris shrimp. Two specific objectives were integrated within the framework of this general objective: (i) to measure the production gain from biofloc rearing and (ii) to study the interaction between biofloc environment and shrimp and to assess its role on production performances of shrimps. Thus, our results show production gains of shrimp reared in biofloc in terms of survival, growth, reproductive performances and quality of larvae. This better performance can be explained by the contribution of natural productivity, estimated between 37 and 40%, in shrimp food. This food supplement, constantly available in the environment, provides energy, nutrients and bioactive molecules. The natural productivity represents a source of lipids, in particular of phospholipids and polyunsaturated fatty acids, which were essential for the reproduction and development of larvae during the lecitotrophic stage; these lipids were accumulated in digestive gland and eggs from females reared in biofloc. The natural food is also a glutathione source, a powerful antioxidant molecule, which contributes to strengthen antioxidant defense system of shrimps and protects lipids against peroxidation, a cause of oxidative stress. Bacteria were dominant in natural productivity of biofloc environment and contribute to shrimp food. Thus, in the last part of this dissertation, we characterized the taxonomic diversity and abundance of bacteria in biofloc environment and showed their influence on shrimp intestinal microbiota. Generally, we observed a better health of biofloc resulting in up-regulation of the studied genes involved in immunity and anti-radical defenses after oxidative stress with hydrogen peroxide. The positive effects of biofloc rearing on survival, growth and reproduction originate from food complement provided by natural productivity
Dallaqua, Bruna [UNESP]. "Intervenção com Azadirachta indica (Neem) na prenhez de ratas diabéticas: repercussões materno-fetais." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/99186.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Diabetes mellitus (DM) é uma síndrome de etiologia múltipla caracterizada por hiperglicemia crônica. Esta hiperglicemia induz o aumento na produção de espécies reativas de oxigênio (ERO) e diminuição das defesas antioxidantes. Devido às complicações causadas pelo diabete, muitos indivíduos optam por terapias alternativas à base de plantas medicinais para amenizar seus efeitos. Sendo assim, nesta revisão de literatura, foram analisados e descritos diversos trabalhos experimentais com a utilização de animais diabéticos para comprovar os efeitos antioxidantes de algumas dessas plantas e verificar se os títulos e resumos disponibilizados nos artigos são compatíveis aos objetivos de nossa busca
Diabetes mellitus (DM) is a syndrome of multiple etiologies characterized by chronic hyperglycemia. This hyperglycemia induces increased production of reactive oxygen species (ROS) and decreased antioxidant defenses. Due to complications caused by diabetes, many people choose for alternative therapies and herbal medicine to alleviate its effects. Thus, in this literature review, several experimental studies with the use of diabetic animals were analyzed to demonstrate the antioxidant effects of some plants and to verify if the titles and abstracts provided in the articles are compatible to the aims of our search
Bond, Jennifer M. "Investigations on antioxidant defence proteins and peptides." Thesis, Cranfield University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278723.
Full textThornley, Andrew Charles. "Antioxidant defence and autoxidative damage in neoplastic disease." Thesis, University of Surrey, 1987. http://epubs.surrey.ac.uk/848118/.
Full textBudde, Heike. "Antioxidant defense in Trypanosoma brucei brucei." [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968912192.
Full textMacedo, Giulianna Echeverria. "Ação de Senecio brasiliensis (spreng) Less sobre a taxa de eclosão e modulação de marcadores de toxicidade em larvas de Drosophila Melanogaster." Universidade Federal do Pampa, 2017. http://dspace.unipampa.edu.br:8080/xmlui/handle/riu/1451.
Full textMade available in DSpace on 2017-05-09T18:30:20Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Ação de Senecio brasiliensis (spreng) Less sobre a taxa de eclosão e modulação de marcadores de toxicidade em larvas de Drosophila Melanogaster.pdf: 2537151 bytes, checksum: c5213c1eaff7c1ecdeaf706e6ced1e1a (MD5) Previous issue date: 2017-03-02
O Brasil apresenta uma rica biodiversidade, sendo que muitas das espécies aqui encontradas tem servido como fonte de compostos com propriedades únicas tanto na medicina como na área biotecnológica. Muitos destes compostos são sintetizados a partir do metabolismo secundário vegetal e nas plantas atuam como atrativos ou mecanismos de defesa. Pesquisas relacionadas com os potenciais das plantas são necessárias para um melhor entendimento das propriedades biológicas que apresentam. Senecio brasiliensis (Spreng) Less., é uma espécie vegetal conhecida popularmente como “maria mole”, presente em pastagens da região Sul do país, sendo suas folhas consumidas pelos animais e capaz de causar hepatotoxicidade. Tal toxicidade se deve ao seu metabolismo secundário, responsável pela síntese de metabólitos tóxicos, principalmente os alcaloides pirrolizidínicos. A espécie é utilizada popularmente para fins medicinais, e possui demonstrada ação tóxica em insetos. Em vista de sua toxicidade e potencial biotecnológico, um estudo mais completo de sua ação se faz necessário. Neste trabalho avaliou-se o efeito biológico da exposição do extrato hidroalcoólico das folhas de Senecio brasiliensis (EHSB) no modelo experimental de Drosophila melanogaster. A análise do perfil fitoquímico do EHSB demonstrou a presença de ácidos fenólicos e flavonoides, e atividade antioxidante in vitro através dos ensaios de ABTS, DPPH, fenóis totais e FRAP. Em ensaios in vivo, EHSB não causou mortalidade de moscas na fase adulta, entretanto a taxa de eclosão foi significativamente diminuída quando as moscas desenvolveram-se em meio de cultura contendo 1 mg/mL de EHSB. Nas larvas do terceiro ínstar observaram-se diminuição da viabilidade celular, aumento da atividade das enzimas antioxidantes GST e SOD, EROs, e diminuição da CAT e aumento da razão GSH/GSSG. Houve aumento na expressão dos genes Nrf2, TrxR, CAT, Drice e Dilp6, e diminuição da fosforilação de proteínas quinases JNK1/2, ERK2 e p38MAPK e AKT, além de um aumento na clivagem de PARP, em paralelo com aumento da atividade de caspase 3/7. Também observou-se uma diminuição nos níveis de glicose, glicogênio e triglicerídeos. O aumento da expressão gênica de Nrf2, da atividade das enzimas GST e SOD e razão GSH/GSSG servem como um indicativo de um estado de estresse oxidativo ocasionado pelo EHSB e atuação da defesa antioxidante das larvas. A diminuição nos níveis de glicose, glicogênio e triglicerídeos pode indicar uma diminuição na reserva energética necessária para fases posteriores ao desenvolvimento larval, como para a eclosão em indivíduo alado, podendo isto ser ocasionado pela inibição da fosforilação de proteínas de transdução de sinal envolvidas neste processo pela diminuição do ATP. Dessa forma, nossos resultados demonstram a toxicidade do HESB e sua capacidade em induzir marcadores de estresse oxidativo e apoptose celular, prejudicando o desenvolvimento de larvas de D. melanogaster e processo de eclosão de moscas adultas.
Brazil has a high biodiversity, and many species found here are source of compounds with unique medicinal and biotechnological properties. These compounds are synthetized by plants secondary metabolism and can act as attractive or defensive to other species. Thus, studies with plant species are necessary to knowledge about their biologial properties. Senecio brasiliensis (Spreng) Less., is a native species popularly known as “maria mole” and is found in pastures of the south region of the country, its leaves serving as food to animals and are able to cause hepatotoxicity due to its secondary metabolism, responsible for the synthesis of toxic metabolites, such as pirrolizidinic alkaloids. In spite of its documented toxicity, this plant is used by Brazilian folk with medicinal purposes. In this study, we have evaluated the biological effects to hydroalcoholic extract of leaves of S. brasiliensis (HESB) exposure in Drosophila melanogaster experimental model. The fruit fly D. melanogaster is an advantageous alternative model useful for the screening of natural substances. Phytochemical constitution of HESB showed the presence of phenolic acids and flavonoids but when comparing with other species, it presented a lower in vitro antioxidant activity by ABTS, DPPH, FRAP assays. Survival and locomotor activity of adult flies was unaltered by extract. Nevertheless, we have observed a significant decreasing in eclosion rate of flies, since its embryonic period at 1 mg/mL concentration of HESB. Biochemical and molecular parameters revealed significant changes in third instar larvae of D. melanogaster exposed to 1 mg/mL of HESB such as decreased cell viability, stimulation of the activity of antioxidant enzymes SOD and GST, decreasing of CAT, and increasing in GSH/GSSG ratio. The mRNA expression of Nrf2, TrxR, CAT, Drice and Dilp6 were also significantly up-regulated. Decreasing in the phosphorylation of JNK1/2, ERK2, p38MAPK and AKT protein kinases were verified. Apoptotic cell death was inducted by extract. This fact was attested PARP cleavage, in parallel with increasing of caspases 3/7 activity. The increased expression of Nrf2, augmented activity of GST and SOD enzymes activities, and GSH/GSSG ratio in parallel with induction of ROS formation, is an indicative of a state of oxidative stress caused by the HESB and the action of the antioxidant defense of the larvae. It was also observed a decreasing in glucose, glycogen and triglycerides levels indicating a diminution in the energetic reserve required for later stages of larval development, such as for eclosion of winged individuals. Therefore, our results demonstrated of the HESB toxicity and its capacity to induce of cell stress markers and of apoptotic cell death impairing thus the development of D. melanogaster larvae and eclosion process of adult flies.
Dallaqua, Bruna. "Intervenção com Azadirachta indica (Neem) na prenhez de ratas diabéticas : repercussões materno-fetais /." Botucatu : [s.n.], 2011. http://hdl.handle.net/11449/99186.
Full textCoorientador: Tiago Rodrigues
Banca: Kleber Eduardo de Campos
Banca: Emilio Herrera
Resumo: Diabetes mellitus (DM) é uma síndrome de etiologia múltipla caracterizada por hiperglicemia crônica. Esta hiperglicemia induz o aumento na produção de espécies reativas de oxigênio (ERO) e diminuição das defesas antioxidantes. Devido às complicações causadas pelo diabete, muitos indivíduos optam por terapias alternativas à base de plantas medicinais para amenizar seus efeitos. Sendo assim, nesta revisão de literatura, foram analisados e descritos diversos trabalhos experimentais com a utilização de animais diabéticos para comprovar os efeitos antioxidantes de algumas dessas plantas e verificar se os títulos e resumos disponibilizados nos artigos são compatíveis aos objetivos de nossa busca
Abstract: Diabetes mellitus (DM) is a syndrome of multiple etiologies characterized by chronic hyperglycemia. This hyperglycemia induces increased production of reactive oxygen species (ROS) and decreased antioxidant defenses. Due to complications caused by diabetes, many people choose for alternative therapies and herbal medicine to alleviate its effects. Thus, in this literature review, several experimental studies with the use of diabetic animals were analyzed to demonstrate the antioxidant effects of some plants and to verify if the titles and abstracts provided in the articles are compatible to the aims of our search
Mestre
Xia, Ling. "Regeneration of the antioxidant ubiquinol by flavoenzymes and the role of antioxidant defence in experimental hepatocarcinogenesis /." Stockholm : [Karolinska institutets bibl.], 2002. http://diss.kib.ki.se/2002/91-7349-244-2.
Full textGunnarsson, Thomas. "The role of antioxidant defence in models of vascular function." Thesis, Queen Mary, University of London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404338.
Full textCarville, David Gerald Michael. "The effect of copper status on blood antioxidant defence enzymes." Thesis, University of Ulster, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328211.
Full textMOREIRA, Vanessa Ribeiro. "ANTIMONIATO DE MEGLUMINA (GLUCANTIME®) CAUSA DANOS AO DNA POR ESTRESSE OXIDATIVO E INDUZ SUPEREXPRESSÃO DE GENES ENVOLVIDOS NA DEFESA ANTIOXIDANTE E REPARO DO DNA." Universidade Federal do Maranhão, 2017. http://tedebc.ufma.br:8080/jspui/handle/tede/1767.
Full textMade available in DSpace on 2017-07-31T14:40:37Z (GMT). No. of bitstreams: 1 Vanessa Ribeiro Moreira.pdf: 4159897 bytes, checksum: a09b5761e215c744dd25a72b0862176f (MD5) Previous issue date: 2017-07-05
FAPEMA, CAPES
Leishmaniasis is a neglected disease caused by more than 20 species of parasites of the Leishmania genus. Pentavalent antimonials are the drugs commonly used for the treatment of leishmaniasi and among then Glucantime® is the first choice drug recommended by the World Health Organization. Its toxic effects are well known, including as genetic damage inducing. However, the mechanism of its genotoxic effect has not been elucidated yet. Given this, we investigated the mechanism by which Glucantime® causes damage to DNA in BALB/c mice infected with Leishmania (Leishmania) infantum, treated with 20mg/kg/day during 20 days. Damage to DNA have been assessed by the comet assay using peripheral blood leukocytes and for assessment of oxidative damage, the comet assay was followed by treatment with the enzymes formamidopyrimidine-DNA-glycosylase (Fpg) and endonuclease III (ENDO III), which recognize and remove oxidized purines and pyrimidines of DNA. The mutagenic potential of the drug was investigated by the micronucleus test in bone marrow cells. The consequences of the oxidative process were measured by the activity of the enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). In addition, we evaluated the expression of genes related to antioxidante defense (GSS, GSTP1, GPx1, SOD1, SOD2 and CAT) and to the DNA repair system (OGG1 and MTH1). Our data demonstrated that Glucantime® causes damage to DNA in mammalian cells by oxidating the nitrogenous bases. The increased frequency of micronucleated cells in animals treated with antileishmanial revealed that the genomic instability was fixed in mutations. In addition, Glucantime® induced overexpression of genes related to the antioxidant defense, as well as the genes OGG1 and MTH1, that work in the DNA repair mechanism of damage caused by oxidation of nitrogen bases. Our data also revealed that infection by L. infantum and the treatment with antimonial significantly increased the enzymatic activity in the SOD-CAT axis, while the SOD-GPx axis was inhibited, probably by the depletion of glutathione. Thus, our data suggests that the antimonial pledges to GPx leading to saturation of the antioxidant system and causes damage to DNA through oxidative stress. These findings were supported by the reduction of genetic damage thought a treatment combined with ascorbic acid, a potent antioxidant. At last, we demonstrated that the stressfull effect of Glucantime® triggers a molecular response in mammalian cells, positively modulating the expression. Of genes related to DNA repair and antioxidant defense.
Leishmaniose é uma doença negligenciada causada por mais de 20 espécies de parasitas do gênero Leishmania. Antimoniais pentavalentes são os fármacos normalmente utilizados para o tratamento das leishmanioses e, dentre estes, o Glucantime® é a droga de primeira escolha recomendada pela Organização Mundial de Saúde. São bastante conhecidos seus efeitos tóxicos, inclusive como indutor de danos genéticos. Entretanto, o mecanismo pelo qual o fármaco exerce seu efeito genotóxico ainda não está elucidado. Nesse sentido, investigamos o mecanismo pelo qual o Glucantime® causa danos ao DNA em camundongos BALB/c infectados com Leishmania (Leishmania) infantum, com regime de tratamento de 20mg/kg/dia durante 20 dias. Danos ao DNA foram avaliados pelo ensaio do cometa usando leucócitos de sangue periférico e, para avaliação de danos oxidativos, o ensaio do cometa foi seguido pelo tratamento com as enzimas formamidopirimidina-DNA-glicosilase (Fpg) e endonuclease III (ENDO III), que reconhecem e retiram bases púricas e pirimídicas oxidadas do DNA. O potencial mutagênico da droga foi investigado pelo teste do micronúcleo em células de medula óssea. As consequências do processo oxidativo foram medidas pela atividade das enzimas superóxido dismutase (SOD), catalase (CAT) e glutationa peroxidase (GPx). Além disso, avaliamos a expressão de genes relacionados à defesa antioxidante (GSS, GSTP1, GPx1, SOD1, SOD2 e CAT) e ao sistema de reparo do DNA (OGG1 e MTH1). Nossos dados demonstraram que o Glucantime® causa danos ao DNA em células de mamíferos pela oxidação das suas bases nitrogenadas. O aumento da frequência de células micronucleadas nos animais sob tratamento com o antileishmanial revelou que a instabilidade genômica foi fixada em mutações. Além disso, o Glucantime® induziu a superexpressão de genes relacionados a defesa antioxidante, bem como dos genes OGG1 e MTH1, que atuam no mecanismo de reparo de danos ao DNA ocasionados por oxidação de bases nitrogenadas. Os nossos dados revelaram também que a infecção por L. infantum e o tratamento com o antimonial aumentou significativamente a atividade enzimática no eixo SOD-CAT, enquanto que o eixo SOD-GPx foi inibido, provavelmente, pela depleção de glutationa. Assim, nossos dados sugerem que o antimonial Glucantime® compromete a atividade da GPx levando a saturação do sistema antioxidante e causa danos ao DNA por estresse oxidativo. Esses achados foram corroborados pela redução dos danos genéticos pelo co-tratamento com o ácido ascórbico, um potente antioxidante. Finalmente, demonstramos que o efeito estressante do Glucantime® dispara uma resposta molecular nas células de mamíferos, modulando positivamente a expressão de genes relacionados ao reparo do DNA e à defesa antioxidante.
Arc-Chagnaud, Coralie. "Regulation of antioxidant defenses in the prevention of skeletal muscle deconditioning." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONT4005.
Full textMusculoskeletal system plays a key role in organism’s well-functioning and is responsible for a large variety of functions such as posture, locomotion, balance, and activities of daily life. The quality of the skeletal muscle is therefore capital to maintain quality of life and, in the long term, survival. Hypoactivity and aging are two situations that cause skeletal muscle deconditioning, therefore sharing common characteristics: loss of muscle strength, muscular atrophy and MyHC redistribution, as well as IMAT accumulation. To date, there is plenty of evidence supporting a causative link between oxidative stress phenomenon and muscle deconditioning.The general aim of this PhD thesis was to evaluate the impact of the modulation of the antioxidant defenses on the prevention of muscle deconditioning. It has been studied from two perspectives, the first one in the context of aging and the second in the context of hypoactivity.The first study aimed to evaluate frailty in old female animals, using WT and G6PD-overexpressing mice. We evaluated muscle quality parameters and oxidative stress markers. Finally, we performed a transcriptomic analysis of muscle samples and highlighted differentially expressed genes in both groups of mice.The second study was conducted to evaluate the effects of a cocktail enriched in antioxidant/anti-inflammatory molecules in a 2-month hypoactivity experiment (Bedrest model). Our results clearly demonstrate the ineffectiveness of this type of supplementation in the prevention of muscle mass and strength loss. Moreover, data regarding muscle molecular mechanisms highlight an alteration of recovery processes in the supplemented subjects.Finally, the conclusions of our two studies gave clues on the suitable antioxidant modulation strategy for the prevention of skeletal muscle deconditioning. It seems preferable to focus on the stimulation of endogenous defense system whether than towards exogenous supply of nutritional antioxidants. Nevertheless, the complexity of redox signaling requires better understanding to optimize countermeasures in muscle wasting situations
Zhang, Zhi Jun. "Investigation into membrane lipid peroxidation and antioxidant defence enzymes in schizophrenia." Thesis, University of Sheffield, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310764.
Full textZitouni, Karima. "Ethnic differences in antioxidant defence in patients with type 2 diabetes." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1446823/.
Full textBotelho, Marina Tenorio. "Biomarcadores na avaliação do estado fisiológico de juvenis de beijupirás, Rachycentron canadum (Linnaeus, 1766), de cultivo." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-11102017-104906/.
Full textThe aquaculture production is continuously growing in the world, even though the marine fish cultures in Brazil are still smaller than its potential. The intention of rearing the cobia (Rachycentron canadum) species is currently increasing due to its high growth rates, adaptability to captivity and acceptance on the market. The intensive culturing conditions may cause stress to the organism, even affecting its physiological state. In this work, cobia has been reared in two different kinds of tanks: the first one was an indoor tank with open water circulation system and the other one was a near shore cage tank. Genotoxic and morphometric parameters and the activity of antioxidant defense enzymes were measured and compared at the end of 11 weeks of culturing. There weren\'t any significant differences between both tanks on the growth rate, but both the comet assay and the micronuclei and others nuclear abnormalities assay detected higher DNA damage and nuclear abnormalities frequency on the fish that were kept at the indoor tank. The comet and the nuclear abnormalities assays seem to be more sensitive to monitoring the physiological state of cobia during the culture. The protein p53, related to DNA integrity, expression was detected by immunohistochemical and didn\'t show significant differences, but the value of the expression was high, so it could indicate that p53 was activated to regulate the DNA damage that was detected by the comet assay. The activity of the enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase also didn\'t demonstrate any significant differences between the fish at any of the tanks. As there isn\'t any known response pattern for the several species of fish that have already been studied, more studies are necessary concerning these enzymes. In addition to the experiment already mentioned, cobia were exposed to β-naphthoflavone (BNF) at concentrations of 2mg/kg and 10mg/kg on laboratory controlled conditions to better understand the response mechanisms of this species to a toxic substance. The genotoxic parameters and the antioxidant defense enzymes activity were measured. The comet assay didn\'t detect any significant differences between the exposed to BNF and the control groups, however the nuclear abnormalities assay showed significant differences between the two exposed concentrations and the control groups. The DNA damages identified by the comet assay are breaks on the DNA strands, meanwhile, nuclear abnormalities are permanent damages. Therefore, during the exposed period it was possible that the time had been sufficient to repair the breaks on DNA. Catalase activity had significant differences with inhibition of the activity in cobia exposed to BNF of higher concentration, the others enzymes didn\'t demonstrate results with significant differences. Looking at both experiments, the comet assay and nuclear abnormalities assay seem to be the most sensitive to cobia\'s monitoring and they also have the advantage that there is no need to sacrifice the fish. Further studies on the antioxidant defense enzymes are needed in order to find a pattern on its response to toxic compounds.
Silva, Maria Isabel Afonso da [UNESP]. "Alterações hematológicas e bioquímicas em uma população de Phrynops geoffroanus (Schweigger, 1812) em reposta a estressores ambientes." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/92533.
Full textOs quelônios estão entre os grupos de vertebrados com maior risco de extinção, sendo as principais ameaças para as populações, a degradação e poluição ambiental. A espécie Phrynops geoffroanus, popularmente conhecida como “Cágado-de-Barbelas”, tem se proliferado em ambiente poluído, sujeita a condições adversas que podem influenciar nos seus hábitos de vida e condições fisiológicas. Estudos que monitorem os efeitos da contaminação ambiental são fundamentais para o conhecimento da biologia da espécie e delineamento de estratégias de conservação efetivas. Deste modo, as análises dos parâmetros hematológicos e bioquímicos mostram-se importantes na avaliação da saúde de animais silvestres e riscos para o animal e ecossistema. O objetivo do trabalho foi verificar a influência do ambiente na fisiologia de uma população de Phrynops geoffroanus por meio da avaliação da capacidade antioxidante e respostas aos estressores ambientais, em comparação com espécimes de local sob condições controladas. Foram avaliadas, por meio do hemograma completo, dosagem de espécies reativas ao ácido tiobarbitúrico (TBARS), ensaio da capacidade antioxidante em equivalência ao Trolox (TEAC) e atividades das enzimas antioxidantes catalase e glicose-6-fosfato desidrogenase (G6PDH), amostras sanguíneas de sessenta espécimes, sendo trinta provenientes do córrego Felicidade, ambiente poluído, no perímetro urbano de São José do Rio Preto-SP; e trinta do criatório “Reginaldo Uvo Leone”, Tabapuã-SP, local sob condições controladas, cujas amostras constituem o grupo controle dos experimentos. Houve grande variação nos parâmetros hematológicos de Phrynops geoffroanus de ambiente urbano. Os valores de glóbulos vermelhos e hemoglobina foram significantemente menores que os observados em animais do criatório (p = 0,0004; p = 0,0371, respectivamente)...
The turtles are among the most endangered vertebrates groups, and the main threats to populations are the environmental pollution and degradation. The species Phrynops geoffroanus, popularly known as Geoffroy's side-necked turtle, has proliferated in polluted environments, subject to adverse conditions that could influence their living habits and physiological conditions. Studies that monitor the effects of environmental pollution are the key to understand the species biology and design effective conservation strategies. Thus, the analysis of hematological and biochemical parameters showed to be important in assessing the health of wild animals and for the animal and ecosystem risks. This work aimed to assess the environmental influence on the physiology of a Phrynops geoffroanus population through the evaluation of antioxidant status and responses to environmental stressors, compared to specimens from a place under controlled conditions. They were evaluated by hemogram, measuring thiobarbituric acid reactive species assay (TBARS), Trolox-equivalent antioxidant capacity evaluation (TEAC) and the activities of antioxidant enzymes, catalase and glucose-6-phosphate dehydrogenase (G6PDH), blood samples of sixty specimens, thirty from the Felicidade stream, polluted environment, within the São José do Rio Preto city, and thirty from the Reginaldo Uvo Leone breeding farm, Tabapuã-SP, place under controlled conditions, whose samples constitute the control group of the experiments. There was a wide variation in hematological parameters of Phrynops geoffroanus from the urban environment. The red blood cells and hemoglobin values were significantly less than those observed in animals from breeding farm (p = 0.0004; p = 0.0371, respectively). There was significant increase of thrombocytes (p < 0.0001) and leukocytes (p < 0.0001) to the animals from the Felicidade stream... (Complete abstract click electronic access below)
Fisher, Gordon Pascoe David D. "Oxidative stress and antioxidant defenses in lymphocytes following high intensity interval training." Auburn, Ala., 2009. http://hdl.handle.net/10415/2003.
Full textPês, Tanise da Silva. "EFEITO DA DIETA ENRIQUECIDA COM RUTINA SOBRE OS PARÂMETROS SANGUÍNEOS E BIOMARCADORES OXIDATIVOS EM JUNDIÁS (Rhamdia quelen)." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/9010.
Full textSilver catfish, Rhamdia quelen, is one of the most cultivated fish species in southern Brazil. Products destined for improving rearing and production of this species are required due to its importance for aquaculture. Oxidative stress (OS) is one of the main challenges in fish culture, so the use of compounds with antioxidant capacity may be valuable. The flavonoid rutin has several beneficial effects and represents an important alternative to reduce the physiological changes that arise from rearing-related stress. This study evaluated the influence of three diets containing rutin (0, 0.15 and 0.30 % rutin) on blood parameters and the antioxidant response of silver catfish. After a 21-day feeding period, blood was withdrawn for biochemical analysis and determination of plasma cortisol levels. The fish were then euthanized for sampling of the brain, gills, liver, kidney and muscle. Biomarkers of OS, thiobarbituric reactive substances (TBARS), lipid hydroperoxides (LOOH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), content of non-protein thiol groups (NPSH), content of ascorbic acid (AA) and total antioxidant capacity (TRAP) were determined. Fish fed the diet having 0.15 % rutin had lower cortisol levels compared to control. Nonetheless, the diet with rutin did not affect the hematological parameters. The levels of lipid peroxidation measured by determination of TBARS and LOOH in the brain, gills, liver and muscle decreased in the fish fed the diet containing rutin; in the kidney, however, only the levels of LOOH were reduced in these fish. When compared to control, the rutin-enriched diet increased the activity of SOD, CAT, NPSH content, AA and TRAP in the brain, GST and TRAP in the gills, SOD, CAT, GST, NPSH content, AA and TRAP in the liver, CAT, GST and TRAP in the kidney, and GPx, NPSH content, AA and TRAP in the muscle. In conclusion, these results suggest that rutin supplementation in silver catfish diet is recommended because it increases the tissue antioxidant response, thus preventing oxidative damage.
O jundiá, Rhamdia quelen, é uma das espécies mais cultivadas no sul do Brasil. Produtos destinados a melhorar o cultivo e produção do jundiá são necessários devido à importância desta espécie para a aquicultura. O estresse oxidativo (OS, do inglês oxidative stress) é um dos principais desafios no domínio da piscicultura, portanto a utilização de compostos com capacidade antioxidante pode ser útil. O flavonoide rutina tem vários efeitos benéficos e torna-se uma alternativa importante a fim de reduzir as alterações fisiológicas resultantes do estresse atrelado ao cultivo. Este estudo avaliou a influência de três dietas contendo a rutina (0, 0,15 e 0,30 % rutina) sobre os parâmetros sanguíneos e resposta antioxidante em jundiás. Após um período de 21 dias de alimentação, o sangue foi coletado para a análise sanguínea. Os peixes foram então eutanasiados para amostragem do encéfalo, brânquias, fígado, rim e músculo. Uma alíquota de sangue foi amostrada para a análise bioquímica e do cortisol plasmático. Os biomarcadores de OS, substâncias que reagem ao ácido tiobarbitúrico (TBARS), hidroperóxidos lipídicos (LOOH), superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx), glutationa S-transferase (GST), o conteúdo dos grupos tióis não proteicos (NPSH), conteúdo de ácido ascórbico (AA) e a capacidade antioxidante total (TRAP) foram determinados. Os peixes que receberam a dieta contendo 0,15 % rutina apresentaram níveis de cortisol mais baixos do que o controle. No entanto, a dieta contendo rutina não influenciou os parâmetros hematológicos. Os níveis de lipoperoxidação medidos por determinação de TBARS e LOOH no encéfalo, brânquias, fígado e músculo diminuíram nos peixes que receberam a dieta contendo rutina; exceto no rim onde houve apenas a redução dos níveis de LOOH em todas as dietas. Quando comparado ao controle, a dieta enriquecida com rutina aumentou a atividade da SOD, CAT, o conteúdo de NPSH, AA e TRAP no encéfalo, GST e TRAP nas brânquias, SOD, CAT e GST, o conteúdo de NPSH, AA e TRAP no fígado, CAT, GST e TRAP no rim, GPx, conteúdo de NPSH, AA e TRAP no músculo. Em conclusão, estes resultados sugerem que a suplementação contendo rutina na dieta do jundiá é recomendada pois aumenta a resposta antioxidante no tecido, evitando o dano oxidativo.
Kunikowska, Grazyna Maria. "Alterations of antioxidant enzymes following manipulations of basal ganglia : relevance to the pathogenesis of Parkinson's disease." Thesis, King's College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313737.
Full textLichten, Louis A. "The roles of zinc and metallothionein in hepatocyte antioxidant defense." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0007024.
Full textClement, Amy Marie. "The Antioxidant Defense Network: Synergistic Combinations to Prevent Oxidative Damage." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1549.
Full textBender, Holly S. "The actions of gossypol on the physiologic antioxidant defense system." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/82901.
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SILVA, Juliana Scanoni. "HPAs biliares e biomarcadores bioquímicos na carapeba Eugerres brasilianus em quatro estuários tropicais do Nordeste brasileiro." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/16475.
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CAPEs
Hidrocarbonetos policíclicos aromáticos (HPAs) são compostos derivados de petróleo conhecidos por seu potencial de toxicidade a organismos aquáticos. Regiões estuarinas são frequentemente contaminadas por HPAs em decorrência de processos de urbanização e atividades industriais, incluindo a cadeia produtiva do petróleo. O trabalho teve o objetivo de avaliar a bioconcentração e efeitos bioquímicos de HPAs em Eugerres brasilianus coletados em quatro estuários no litoral sul de Pernambuco, a fim de obter um diagnóstico da poluição por estes contaminantes nestas regiões. As coletas foram realizadas no rio Ariquindá, sistema estuarino do rio Formoso (AR-SERF), no rio Massangana, no complexo estuarino de Suape (MA-CES), no sistema estuarino de Barra de Jangada (SEBJ), e no complexo estuarino da bacia do Pina (CEBP). A bile dos peixes foi analisada por Fluorescência Fixa para estimar a concentração em equivalentes dos HPAs naftaleno, fenantreno e criseno. Amostras de fígado foram utilizadas para análise de biomarcadores enzimáticos de fase I (etoxiresorufina orto-deetilase, EROD), fase II (glutationa S-transferase, GST), e defesa antioxidante (catalase, CAT, e glutationa redutase, GR). A análise de HPAs na bile e atividades enzimáticas em peixes coletados num ciclo anual em MA-CES e AR-SERF indicou uma semelhança na contaminação por HPAs na bile e nos níveis de atividades enzimáticas dos biomarcadores avaliados entre estes estuários, apesar da diferença do padrão de atividades antrópicas destas regiões. O CES comporta um complexo portuário com alta atividade industrial enquanto o SERF possui baixa densidade populacional e atividades turísticas. Os peixes coletados em SEBJ e CEBP apresentaram bile com concentrações do HPA criseno entre 13 x e 19 x maiores que AR-SERF, respectivamente. Foi detectado aumento das atividades da EROD, GST e CAT das regiões do SEBJ e CEBP, chegando a 30 x para a EROD, e aproximadamente 2 x para GST e CAT em comparação com AR-SERF. A maior bioconcentração de HPAs na bile e maior indução enzimática nos peixes E. brasilianus do SEBJ e CEBP indicam que estes estão dispendendo energia para tentar se adaptar a esta contaminação, o que pode ter consequências para o seu crescimento e sobrevivência nestas regiões. Os resultados indicam que SEBJ e CEBP recebem um maior aporte de HPAs, associado a maior densidade populacional e atividades antrópicas nas bacias desses rios. Os parâmetros utilizados serão úteis para o monitoramento destes sistemas estuarinos, em especial do CES, em franco processo de urbanização e industrialização.
Polycyclic aromatic hydrocarbons (PAHs) are oil derived compounds known for their toxicity potential towards aquatic organisms. Estuarine regions are frequently contaminated with PAHs as a result of urbanization processes and industrial activities, including the oil productive chain. The work aimed to evaluate the bioconcentration and the biochemical effects of PAHs in Eugerres brasilianus sampled from four estuaries in the south coast of Pernambuco, in order to obtain a pollution diagnosis by these contaminants in such regions. The data collection was made in the Aquirindá river, Rio Formoso estuarine system (AR-RFES), in the Massangana river, in the Suape’s estuarine complex (MA-SEC), in the Barra de Jangada estuarine system (BJES) and in the Bacia do Pina estuarine complex (BPEC). The fish’s bile were analyzed using fixed fluorescence to estimate the equivalent concentrations of the PAHs naphthalene, phenanthrene and chrysene. Liver samples were used for phase 1 enzymatic biomarkers analysis (Ethoxyresorufin-O-deethylase, EROD), phase II (glutathione S-transferase, GST) and antioxidant defense (catalase, CAT, and glutathione reductase, GR). The analyzes of PAHs in bile and enzymatic activity in fish that were sampled in an annual cycle in MA-SEC and AR-RFES indicated a similarity between PAHs contamination in bile and the enzymatic activity levels of the biomarkers evaluated among these estuaries, despite the different anthropogenic activity patterns. The SEC comprises a port complex with high industrial activity, while the RFES has low population density and touristic activities. The bile of the fish sampled in BJES and BPEC showed chrysene concentration between 13 x and 19 x higher than AR-RFEC, respectively. An increase in EROD, GST and CAT activities was detected in the regions of BJES and BPEC, reaching 30 x for EROD, and approximately 2 x for GST and CAT. The high PAHs bioconcentration in the bile and the high enzymatic induction in E. brasilianus fish from BJES and BPEC indicate that these fish are wasting energy to try to become adapted to this contamination, which may have consequences to their growth and survival in such regions. The results indicate that BJES and BPEC receive a greater input of PAHs, associated with the higher population density and anthropogenic activities in these rivers’ basins. The parameters used will be useful for the monitoring of these estuarine systems, especially in SEC, which suffers with a rapid urbanization and industrialization process.
Pietarinen-Runtti, Petra. "Regulation of antioxidant defense in cells derived from the human lung." Helsinki : University of Helsinki, 2000. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/pietarinen-runtti/.
Full textFreitas, Robson Borba de. "AVALIAÇÃO DA TOXICIDADE DO EXTRATO AQUOSO DE Scutia buxifolia EM RATOS." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/5958.
Full textMedicinal plants were and are very important for healing various diseases. However, improper use of plants for therapeutic purposes can cause a number of side effects. There are in the literature various reports about plants induced-toxicity and, in some cases patients have hepatic disorders. The knowledge about toxicity of vegetable materials is insipient because there are few scientific studies related to pharmacokinetics and pharmacodynamics. Plants containing pyrrolizidine alkaloids show hepatotoxic effects well documented. Scutia buxifolia Reiss is a Rhamnaceae. This plant occurred in Uruguay, Argentina and Brazil. It is used for hypertension treatment. Extracts and fractions obtained from S. buxfolia have antimicrobial and antioxidants effects. Nevertheless, S. buxifolia toxic effects are unknown. The present study was aimed to evaluate the acute and sub-chronic toxicity of S. buxifolia aqueous extract (SBSB). The flavonoids, condensed tannins, and flavonoids were measured in SBSB. The antioxidant scavenger capacity of SBSB was determined by DPPH assay. Antioxidant power of SBSB was comparable with the antioxidant ascorbic acid. The single dose of SBSB at concentrations 100, 200, 400 mg/ kg body weight administered to Wistar rats did not cause mortality and, behavioral changes. Then, we speculate that the lethal dose of SBSB is greater than 400 mg / kg body weight. In the sub-chronic assay, thirty-two animals are divides in 4 groups: the control group which receive distilled water by gavage and, the experimental groups which received the same doses used in the acute toxicity assay. The animals received water or SBSB once a day, during 30 days. The serum alanine aminotransferase (ALT) and asparate aminotransferase (AST) activities and, serum albumin levels were measured on 15º and 30º day of treatment. The malondialdehyde (MDA) and non-protein thiol groups (NPSH) contents and, the antioxidant activities of superoxide dismutase (SOD) and catalase (CAT) were quantified in the liver. Treatment with SBSB did not elevate the activity of AST and ALT, and did not alter the level of serum albumin in the doses of 100 and 400 mg / kg body weight. In animals treated with 200 mg / kg an increased activity of the enzyme AST was observed. This fact can occurred due, probably, to hemolysis. Treatment with SBSB preserves antioxidant defenses and does not increase the lipid peroxidation in liver tissue. These findings along with histopathological analysis show that the SBSB is safe.
As plantas medicinais foram e são de suma importância para a cura de diversas doenças. No entanto, o uso indiscriminado de plantas para fins terapêuticos pode provocar uma série de efeitos colaterais. Existem na literatura, vários relatos de intoxicação por plantas mundialmente usadas e em alguns casos, pacientes apresentaram falência hepática. O conhecimento dos efeitos tóxicos de matérias vegetais ainda é bastante insipiente, pois, há poucos trabalhos científicos sobre farmacocinética e farmacodinâmica. Plantas que contêm alcalóides pirrolizidínicos apresentam efeitos tóxicos para o fígado e já foram bem documentadas. Scutia buxifolia é uma Rhamnaceae que ocorre no Uruguai, Argentina e Brasil. Esta planta é popularmente usada no tratamento da hipertensão. Extratos e frações das folhas e cascas de S. buxifolia já tiveram suas atividades antimicrobianas e antioxidantes investigadas. Porém, os efeitos tóxicos do extrato de S. buxifolia são pouco conhecidos. O presente estudo teve como objetivo principal avaliar a toxicidade aguda e sub-crônica do extrato aquoso de S. buxifolia (SBSB). Neste extrato quantificou-se o conteúdo total de compostos fenólicos, taninos condensados, e flavonóides. A atividade antioxidante do SBSB determinada pelo método do DPPH é comparável á do ácido ascórbico. A dose única do SBSB nas concentrações de 100, 200 e 400 mg / kg de peso corporal administrada a ratos da raça Wistar, não causou mortalidade nos grupos e nem alterações comportamentais. Então, especula-se que a dose letal do SBSB seja maior que 400 mg/ kg de peso corporal. No ensaio sub-crônico, trinta e dois animais foram divididos em quatro grupos: o controle que recebeu água e, os experimentais que receberam o extrato nas mesmas doses que as utilizadas no ensaio da toxicidade aguda. Os animais receberam água ou extrato uma vez ao dia via gavagem, durante 30 dias. A atividade sérica das enzimas alanina aminotransferase (ALT) e asparato aminotransferase (AST) e o nível de albumina foram mensurados no 15º de 30º dia de tratamento. O conteúdo de malondialdeído (MDA), de tióis não-protéicos e atividade antioxidante das enzimas catalase (CAT) e superóxido dismutase (SOD) foram quantificadas no fígado dos animais. O tratamento com o SBSB não eleva a atividade da AST e da ALT e, não alterara o nível sérico de albumina nas doses de 100 e 400 mg/ kg de peso corporal. Os animais tratados com a dose de 200 mg/kg tiveram um aumento na atividade da enzima AST. O tratamento com SBSB preserva as defesas antioxidantes e não aumenta a peroxidação lipídica no tecido hepático. Esses achados juntamente com análise histopalógica mostram que o SBSB é seguro.
Hamlin, Scott A. "Effects of resistance exercise on markers of inflammation and antioxidant defenses in heart transplant recipients." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010509.
Full textBorçari, Nathalia Ruder. "Efeito da progesterona na expressão de genes envolvidos no estresse oxidativo e defesa antioxidante em células beta pancreáticas: uma abordagem in vitro para o estudo do diabetes gestacional." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/100/100142/tde-21052018-223214/.
Full textGestational diabetes (GD) is a condition defined as carbohydrate intolerance and hyperglycemia, beginning in the second trimester of pregnancy. Studies developed by our group have shown that progesterone (PG) is able to cause pancreatic cells death, by a mechanism dependent on the generation of free radicals, which could contribute to the development of GD. The aim of this work was to study the effect of PG, in the presence or absence of antioxidants, on the expression of genes related to oxidative stress and oxidant defense in pancreatic cells of the RINm5F lineage. Cells were incubated with 0.1, 1.0 and 100 µM PG for 6 or 24 h, in the presence or absence of vitamin E and C antioxidants. PG did not cause loss of membrane integrity of RINm5F cells, however, it promoted DNA fragmentation in approximately 40% of the RINm5F and MCF-7 cells (positive control), whereas vitamin E and C antioxidants reduced such fragmentation. From the RNA extraction and cDNA synthesis was investigated the expression of 84 genes involved in oxidative stress and antioxidant defense. Among of 84 investigated genes, five of them had their expression increased, in the minimum 2-fold in, at least, two different concentrations independent of incubation time (6 or 24 h), or at the same concentrations at different times, such as those that encoding for heat shock protein a1a (Hspa1a), glutathione peroxidase 6 (Gpx6), dual oxidase 1 (Duox1), heme oxygenase 1 (Hmox1) and stearoyl-CoA denaturase 1 (Scd1). These genes, together with the peroxiredoxin 4 (Prdx4), play an important role in pancreatic cell physiology and/or DG. The gene expression was also studied in the preincubation of RINm5F cells with vitamin E and C. These antioxidants were generally able to increase the Hmox1 and Prdx4 expression, genes with antioxidant functions, and decrease the Scd1 expression, a gene with pro-oxidant function. At the cytoplasmic level, it was found that the amounts of Hmox1 and Prdx4 proteins were also modulated by PG and / or vitamin E and C. The results suggest that these antioxidants play an important role in the RINm5F protection cells against the oxidative damage induced by PG. Thus, the results obtained in this project, together, should contribute to a better understanding of the pathogenesis of DG, opening new perspectives not only to elucidate the molecular mechanism involved in the action of PG on pancreatic cells and its relationship with DG, but for the development of strategies for the prevention and treatment of this disease based on antioxidant therapy
Marmolino, Daniele. "Alterations of mitochondrial biogenesis and alterations of mitochondrial antioxidant defense in Friedreich's ataxia." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209972.
Full textFrataxin function is not yet completely elucidated. In frataxin deficiency conditions abnormalities of iron metabolism occur: decreased activities of iron-sulfur cluster (ISC) containing proteins, accumulation of iron in mitochondria and depletion in the cytosol, enhanced cellular iron uptake, and, in some models, reduced heme synthesis.
Evidence of oxidative stress has also been found in most though not all models of frataxin deficiency. Accordingly, yfh1-deficient yeast and cells from FRDA patients are highly sensitive to oxidants. Respiratory chain dysfunction further aggravate oxidative stress by increasing leakage of electrons and the formation of superoxide. Frataxin deficient cells not only generate more free radicals, but, they also show a reduced ability to mobilize antioxidant defenses, in particular to induce superoxide dismutase 2 (SOD2).
Peroxisome proliferator-activated receptor (PPAR) isoform-gamma play a key role in numerous cellular functions and is a key regulator of mitochondrial biogenesis and of the ROS metabolism. Recruitment of the PPAR coactivator-1a (PGC-1a) mediates many effects of the PPAR-γ activation.
In a first work we assessed the potential beneficial effects of a potent PPAR-gamma agonist on frataxin expression in primary fibroblasts from healthy controls and FRDA patients, and Neuroblastoma cells. We used the APAF molecule (1-0-hexadecyl-2-azelaoyl-sn-glycero-3-phosphocoline; C33H66NO9P). Our results show that this compound is able to increase frataxin amount both at transcriptional and post-transcriptional level. At a dose of 20µM frataxin mRNA significantly increases in both controls (p=0.03) and FRDA patients (p=0.002) fibroblasts (1). The finding was confirmed in Neuroblastoma cells (p=0.042). According to previous publications APAF, as others PPAR-gamma agonists is able to up-regulate PGC-1a transcription.
In a second part of the study we investigate the role of the PPAR-gamma/PGC-1a pathway in the pathogenesis of FRDA. We performed a microarray analysis of heart and skeletal muscle in a mouse model of frataxin deficiency and we found molecular evidence of increased lipogenesis in skeletal muscle and alteration of fiber-type composition in heart, consistent with insulin resistance and cardiomyopathy, respectively. Since the PPAR-gamma pathway is known to regulate both processes, we hypothesized that dysregulation of this pathway could play a key role in frataxin deficiency. We confirmed this by showing a coordinate dysregulation of Pgc1a and the transcription factor Srebp1 in cellular and animal models of frataxin deficiency, and in cells from FRDA patients, who have marked insulin resistance. Particularly, PGC-1a was found significantly reduced (2) in primary fibroblasts and lymphocytes from FRDA patients (p<0.05). Furthermore, PGC-1a mRNA levels strongly correlate with frataxin relative mRNA levels (r2=0.9, p<0.001). According to this observation, in C2C12 myoblasts, PGC-1a and a reporter gene under the control of the PGC-1a promoter are rapidly down-regulated (p<0.05) when frataxin expression is inhibited by an shRNA in vitro. To further investigate this relation, we then generate PGC-1a deficient fibroblasts cells using a specific siRNA; at 72 hours of transfection frataxin was found down-regulate (p<0.05) in control cells.
Taken together those data indicate that some mechanism directly links an early effect of frataxin deficiency with reduced PGC-1a transcription in this cell type, and presumably in other cells that also down-regulate PGC-1α when frataxin levels are low.
Finally, since PGC-1a has also emerged as a key factor in the induction of many antioxidant programs in response to oxidative stress, both in vivo and in vitro, in particular in neurons, we tested whether the PGC-1a down-regulation occurring in FRDA cells could be in part responsible for the blunted antioxidant response observed in frataxin deficiency.
Using primary fibroblasts from FRDA patients we found reduced SOD2 levels (p<0.05), according to PGC1&
Doctorat en Sciences biomédicales et pharmaceutiques
info:eu-repo/semantics/nonPublished
Silva, Maria Isabel Afonso da. "Alterações hematológicas e bioquímicas em uma população de Phrynops geoffroanus (Schweigger, 1812) em reposta a estressores ambientes /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/92533.
Full textBanca: Lilian Castiglioni
Banca: Fabiano Gazzi Taddei
Resumo: Os quelônios estão entre os grupos de vertebrados com maior risco de extinção, sendo as principais ameaças para as populações, a degradação e poluição ambiental. A espécie Phrynops geoffroanus, popularmente conhecida como "Cágado-de-Barbelas", tem se proliferado em ambiente poluído, sujeita a condições adversas que podem influenciar nos seus hábitos de vida e condições fisiológicas. Estudos que monitorem os efeitos da contaminação ambiental são fundamentais para o conhecimento da biologia da espécie e delineamento de estratégias de conservação efetivas. Deste modo, as análises dos parâmetros hematológicos e bioquímicos mostram-se importantes na avaliação da saúde de animais silvestres e riscos para o animal e ecossistema. O objetivo do trabalho foi verificar a influência do ambiente na fisiologia de uma população de Phrynops geoffroanus por meio da avaliação da capacidade antioxidante e respostas aos estressores ambientais, em comparação com espécimes de local sob condições controladas. Foram avaliadas, por meio do hemograma completo, dosagem de espécies reativas ao ácido tiobarbitúrico (TBARS), ensaio da capacidade antioxidante em equivalência ao Trolox (TEAC) e atividades das enzimas antioxidantes catalase e glicose-6-fosfato desidrogenase (G6PDH), amostras sanguíneas de sessenta espécimes, sendo trinta provenientes do córrego Felicidade, ambiente poluído, no perímetro urbano de São José do Rio Preto-SP; e trinta do criatório "Reginaldo Uvo Leone", Tabapuã-SP, local sob condições controladas, cujas amostras constituem o grupo controle dos experimentos. Houve grande variação nos parâmetros hematológicos de Phrynops geoffroanus de ambiente urbano. Os valores de glóbulos vermelhos e hemoglobina foram significantemente menores que os observados em animais do criatório (p = 0,0004; p = 0,0371, respectivamente)... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The turtles are among the most endangered vertebrates groups, and the main threats to populations are the environmental pollution and degradation. The species Phrynops geoffroanus, popularly known as "Geoffroy's side-necked turtle", has proliferated in polluted environments, subject to adverse conditions that could influence their living habits and physiological conditions. Studies that monitor the effects of environmental pollution are the key to understand the species biology and design effective conservation strategies. Thus, the analysis of hematological and biochemical parameters showed to be important in assessing the health of wild animals and for the animal and ecosystem risks. This work aimed to assess the environmental influence on the physiology of a Phrynops geoffroanus population through the evaluation of antioxidant status and responses to environmental stressors, compared to specimens from a place under controlled conditions. They were evaluated by hemogram, measuring thiobarbituric acid reactive species assay (TBARS), Trolox-equivalent antioxidant capacity evaluation (TEAC) and the activities of antioxidant enzymes, catalase and glucose-6-phosphate dehydrogenase (G6PDH), blood samples of sixty specimens, thirty from the Felicidade stream, polluted environment, within the São José do Rio Preto city, and thirty from the "Reginaldo Uvo Leone" breeding farm, Tabapuã-SP, place under controlled conditions, whose samples constitute the control group of the experiments. There was a wide variation in hematological parameters of Phrynops geoffroanus from the urban environment. The red blood cells and hemoglobin values were significantly less than those observed in animals from breeding farm (p = 0.0004; p = 0.0371, respectively). There was significant increase of thrombocytes (p < 0.0001) and leukocytes (p < 0.0001) to the animals from the Felicidade stream... (Complete abstract click electronic access below)
Mestre
Anschau, Valesca. "Estresse oxidativo e parâmetros hematológicos como biomarcadores da infecção experimental com Trypanosoma evansi em ratos." Universidade do Estado de Santa Catarina, 2011. http://tede.udesc.br/handle/handle/843.
Full textTrypanosoma evansi is a hemoflagellate parasite that had known to cause infection in a variety of mammals, such as camels, cattles, horses, buffaloes, pigs, dogs and other animal species in tropical and subtropical áreas. In Brazil, T. evansi is considered endemic only at Pantanal, but has been also found in the central region of Rio Grande do Sul and Santa Catarina also. High levels of parasitemia with rapid development of anemia characterize the disease, however the mechanisms of development are still unknown. In this study we aimed to investigate the effect of oxidative stress in erythrocytes and evaluate hematological parameters in rats experimentally infected with T. evansi. Due to, sixty male Wistar rats, were inoculated intraperitoneally with blood containing 103 trypanosomes and fifteen were negative control. The parasitemia was evaluated each 12 hours and the animals were allocated in five groups according to average parasitemia in 10 random homogeneous microscopic fields: (A) uninfected group (control); (B) rats with 1-10 trypanosomes/field; (C) 11-30 trypanosomes/field; (D) 31-60 trypanosomes/field; and (E) more than 61 trypanosomes/field. The animals that achieved the number of trypanosomes equivalent to the groups were sacrificed and blood samples collected to measurement the activities of glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), glucose-6-phosphate dehydrogenase (G6PD), catalase (CAT), and glutathione (total and oxidized), protein thiols (PSH) and non-protein (NPSH). As well as, serum iron, plasma glucose, osmotic fragility, methemoglobin levels, markers of oxidative stress as total and lipid peroxides levels and protein carbonyl concentration (PC) were quantified. Hematological parameters were also analyzed such as erythrocyte count, hematocrit, hemoglobin concentration, packed cell volume, mean corpuscular volume, mean corpuscular hemoglobin concentration, total plasma proteins, platelets, reticulocytes and differential leukocytes count. The infected groups with greater development of the disease developed anemia, with low reticulocytes and platelets levels. Besides that, the increasing of erythrocyte osmotic fragility and methemoglobin levels was observed in groups D and E. In group E was observed a significant reduction of plasma glucose levels when compared with the control group (64%). The serum iron decreased to 58% in group B, but increased to 78% in group E. The acute infection caused an increase in GPx activity in group C, D and E, and enhances CAT activity in group D and E respectively. However, decreased the GR activity in group E approximately 52%. There were no significant differences in the activities of GST and G6PD in the groups comparing to the control. Infection with T. evansi caused a consumption of GSH-t (48%) and a reduction of the levels of PSH and NPSH, around 55%. As well, infected animals showed an increase of the levels of total and lipid peroxides, more than 90% PC concentration compared with the control. Finally, T. evansi promoted oxidative damage in infected rats through increasing antioxidant activities of GPx, CAT, depletion of GSH-t, PSH and NPSH, and inhibition of GR activity. Moreover, the infection also increased the levels of PC, total and lipid peroxides in higher stages of infection caused by T. evansi. Therefore, we can to state that oxidative damage in erythrocytes contributes decisively to the development of anemia in infection by T. evansi in rats
O Trypanosoma evansi é um hemoparasita flagelado conhecido por causar infecção em uma diversidade de mamíferos como camelos, bovinos, equinos, bubalinos, suínos, caninos e outras espécies animais em áreas tropicais e subtropicais. No Brasil, T. evansi é considerado endêmico apenas no Pantanal, mas também já foi encontrada na região central do Rio Grande do Sul e em Santa Catarina. Altos níveis de parasitemia com rápido desenvolvimento de anemia caracterizam a doença, contudo seus mecanismos de desenvolvimento ainda são desconhecidos. Este estudo teve como objetivo investigar o efeito do estresse oxidativo em eritrócitos e avaliar parâmetros hematológicos de ratos infectados experimentalmente com T. evansi. Para isso, sessenta ratos Wistar machos foram inoculados via intraperitonial com sangue contendo 103 tripanossomas e quinze foram usados como controle negativo. A parasitemia foi avaliada a cada 12 horas e os animais foram alocados em cinco grupos de acordo com a média de tripanossomas em 10 campos homogêneos focados aleatoriamente sendo: (A) grupo não infectado (controle); (B) ratos com 1-10 tripanossomas/campo; (C) 11-30 tripanossomas/campo; (D) 31 a 60 tripanossomas/campo; and (E) com mais de 61 tripanossomas/campo. Os animais que apresentaram o número de tripanossomas equivalente ao grupo, foram sacrificados e amostras de sangue coletadas para mensuração das atividades da glutationa peroxidase (GPx), glutationa redutase (GR), glutationa-S-transferase (GST), glicose-6-fosfato desidrogenase (G6PD), catalase (CAT), e glutationa (total e oxidada), tióis protéicos (PSH) e não protéicos (NPSH). Assim como ferro sérico, glicose plasmática, fragilidade osmótica, níveis de metahemoglobina, marcadores de estresse oxidativo como peróxidos totais e lipídicos e níveis de proteína carbonilada (PC) foram quantificados. Também foram analisados parâmetros hematológicos tais como contagem total eritrócitos, hematócrito, concentração de hemoglobina, volume globular, volume globular médio, concentração hemoglobina corpuscular média, proteínas plasmáticas totais, plaquetas, reticulócitos, e contagem diferencial de leucócitos. Os grupos infectados com maior desenvolvimento da doença apresentaram anemia, com diminuição nos reticulócitos e plaquetas. Além disso, o aumento na fragilidade osmótica eritrocitária e nos níveis de metahemoglobina nos grupos D e E foi observada. No grupo E foi observada uma redução significativa nos níveis de glicose plasmática quando comparado ao grupo controle (64%). O ferro sérico diminuiu 78% no grupo B, mas aumentou 78% no grupo E. A infecção aguda causou um aumento da atividade da GPx nos grupos C, D e E e um aumento da atividade da CAT nos grupos D e E respectivamente. Entretanto, ocorreu uma diminuição da atividade da GR no grupo E de aproximadamente 52%. Não foram encontradas diferenças significativas nas atividades da GST e G6PD nos grupos comparados com o controle. Infecção com T. evansi causou um consumo da GSH-t (48%) e uma redução nos níveis de PSH e NPSH, de aproximadamente 55%. Assim como, animais infectados mostraram um aumento nos níveis de peróxidos totais e lipídicos, na concentração de PC de mais de 90% comparado com o controle. Em resumo, T. evansi promoveu insulto oxidativo em ratos infectados através do aumento das atividades da GPx, CAT, depleção da GSH-t, PSH e NPSH, inibição da atividade da GR. Além disso, a infecção também aumentou os níveis de PC, peróxidos totais e lipídicos nos estágios de maior infecção causada pelo T. evansi. Diante disso, é possível afirmar que danos oxidativos em eritrócitos contribuem decisivamente para o desenvolvimento de anemia na infecção por T. evansi em ratos
Baker, Amanda Fern 1969. "Modulation of the antioxidant defense during dexamethasone-induced apoptosis in WEHI7.2 mouse lymphoid cells." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/282473.
Full textBattisti, Vanessa. "ESTUDO DO PERFIL OXIDATIVO E AVALIAÇÃO DE PARÂMETROS ENZIMÁTICOS EM PACIENTES COM CÂNCER DE PRÓSTATA." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/4450.
Full textProstate cancer is recognized as one of the most important medical problems in the male population. Inherent or acquired alterations in cellular metabolism that occur over the years may be involved in the process of developing this cancer. Thus, oxidative stress may play an important role in cellular processes associated with the initiation and development of prostate cancer. On the other hand, the cancer may be associated with changes in platelet aggregation and metabolism of nucleotides. In addition, enzymes that degrade esters of choline are well known as participating in non-cholinergic functions and intervene in important cell processes such as proliferation, differentiation and apoptosis. Considering such statements, this study aimed to evaluate the oxidative profile, through the determination of parameters such as the TBARS and protein carbonyl content and antioxidant defenses, by determine the catalase (CAT) and superoxide dismutase (SOD) activity and non-protein thiols, vitamin C and vitamin E levels. Also, determine ectonucleotidases enzyme activities represented by the enzymes NTPDase, E-NPP, 5'nucleotidase and adenosine deaminase (ADA) and verified the acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities. In addition, we evaluated the influence of Gleason score, the presence or absence of metastasis and type of treatment used by patients in the parameters analyzed. The results show that the content of TBARS and protein carbonylation levels increased in patients when compared with the control group. In addition, changes in the antioxidant defenses were observed. The CAT activity was decreased and SOD activity increased in patients compared to controls. We found also an increase in the levels of non-protein thiols in plasma and erythrocytes and a decrease in serum levels of vitamin C and vitamin E in patients. These results suggest an increased formation of reactive species and an imbalance in the enzymatic and non-enzymatic antioxidant system defense in patients with prostate cancer. Moreover, it was observed that advanced prostate cancer is associated with a state of high oxidative stress. The results showed that nucleotides hydrolysis (ATP, ADP and AMP) were increased in patients compared to controls, which maybe observed by the increase in the enzymes activity (NTPDase, E-NPP and 5'Nucleotidase). On the other hand, our results showed a decrease in ADA activity in serum of these patients. These results reflect the increase in the nucleotide hydrolysis and the consequent increase in the adenosine concentrations that may be envolved in the tumorigenesis process. Our results also showed that inhibition of platelet aggregation was decreased only in patients with prostate cancer before starting treatment. The AChE and BuChE activities were decreased in patients in relation to the control group. The decrease in the cholinesterases activities and the consequently increase in acetylcholine levels suggest the participation of this molecule in the process of cancer development. Finally, changes in the NTPDase, 5' nucleotidase, E-NPP, ADA, AChE and BuChE activities when patients were divided in groups considering the Gleason score, presence or absence of bone metastasis and the treatment, indicate that these parameters must be considered.
O câncer de próstata é reconhecido como um dos mais importantes problemas médicos enfrentados pela população masculina. Alterações inerentes ou adquiridas no metabolismo celular que ocorrem ao longo dos anos podem ter envolvimento no processo de desenvolvimento deste tipo de câncer. Dessa forma, o estresse oxidativo pode desempenhar um papel importante nos processos celulares associados com a iniciação e o desenvolvimento do câncer de próstata. Por outro lado, o câncer pode estar associado com alterações na agregação plaquetária e no metabolismo dos nucleotídeos. Além disso, as enzimas que degradam ésteres de colina desempenham funções não colinérgicas e parecem estar envolvidas com a proliferação e diferenciação celular. Levando em consideração tais afirmativas, este trabalho teve como objetivos avaliar o perfil oxidativo, através da determinação do conteúdo de substâncias reativas ao ácido tiobarbitúrico (TBARS) e de proteína carbonil, e as defesas antioxidantes, através da determinação das atividades das enzimas catalase (CAT) e superóxido dismutase (SOD) e dos níveis de tióis nãoprotéicos, vitamina C e vitamina E. Além disso, realizar a determinação das atividades das enzimas ectonucleotidases representadas pelas enzimas NTPDase, E-NPP, 5 nucleotidase e adenosina deaminase (ADA). Por fim, verificar as atividades das enzimas acetilcolinesterase (AChE), butirilcolinesterase (BuChE) e os parâmetros bioquímicos em pacientes e controles. Esse trabalho teve ainda como objetivo, avaliar a influência da escala de Gleason, da presença ou ausência de metástase e do tipo de tratamento a que foram submetidos os pacientes, nas dosagens realizadas. Os resultados demonstram que o conteúdo de TBARS e os níveis de carbonilação de proteínas aumentaram nos pacientes quando comparados com o grupo controle e mudanças no sistema de defesa antioxidante foram observadas. A atividade da CAT estava diminuída e a atividade da SOD aumentada nos pacientes quando comparados aos controles. Verificamos ainda um aumento nos níveis de tióis não-protéicos no plasma e eritrócitos e uma diminuição nos níveis séricos de vitamina C e de vitamina E em pacientes com câncer próstata. Os resultados mostraram que a hidrólise dos nucleotídeos ATP, ADP e AMP estava aumentada nos pacientes quando comparado ao grupo controle, o que pode ser comprovado pelo aumento nas atividades das enzimas NTPDase, E-NPP e 5 Nucleotidase. Por outro lado, nossos resultados revelaram uma diminuição na atividade da ADA no soro desses pacientes. Os resultados mostraram também que a agregação plaquetária foi diminuída apenas nos pacientes com câncer de próstata antes do início do tratamento. As atividades da AChE e BuChE foram diminuídas 8 nos pacientes em relação ao grupo controle. Com os dados podemos concluir que há um aumento na formação de espécies reativas e um desequilíbrio no sistema de defesa antioxidante enzimático e não-enzimático nos pacientes. Além disso, o câncer de próstata avançado pode estar associado com um estado de estresse oxidativo elevado. Os resultados refletem também o aumento na hidrólise de nucleotídeos e o consequente aumento nas concentrações de adenosina nos pacientes, que pode estar participando do processo de tumorogênese. A diminuição nas atividades das colinesterases (AChE e BuChE) e o consequente aumento nos níveis de acetilcolina sugerem a participação da mesma no processo de desenvolvimento do câncer. Finalmente, as alterações nas atividades das enzimas NTPDase, 5 Nucleotidase, E-NPP, ADA, BuChE e AChE quando os pacientes foram divididos em grupos considerando a escala de Gleason, a presença ou ausência de metástase óssea e o fato de estar ou não em tratamento, indicam que esses parâmetros devem ser considerados.
Peña, Ahumada Andrea Alejandra. "Antioxidant defence and the role of the peroxiredoxins during silique development and seedling establishment in oilseed plants." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=980373115.
Full textJiang, Mingyi. "Role and mechanism of abscisic acid in the induction of antioxidant defense in maize leaves." HKBU Institutional Repository, 2002. http://repository.hkbu.edu.hk/etd_ra/415.
Full textSaccol, Etiane Medianeira Hundertmarck. "ADIÇÃO DO ÓLEO ESSENCIAL DE Lippia alba (MILL) N. E. BROWN NA DIETA DO JUNDIÁ: ANÁLISE DO CRESCIMENTO E DA RESPOSTA ANTIOXIDANTE." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/9015.
Full textFish become more susceptible to stress and, consequently, to the onset of disease with the intensification of rearing. In an attempt to minimize this problem, farmers use agrochemicals that, besides harming the environment, can also affect producers and consumers health. The essential oil (EO) of Lippia alba may be a natural alternative since it has several effects that can reduce the physiological changes resulting from stress inherent in aquaculture. The influence of five diets containing L. alba EO (0, 0.25, 0.5, 1.0 and 2.0 mL of EO per kg of diet) on growth and antioxidant response in juvenile silver catfish was evaluated. After a feeding period of 60 days, the silver catfish were weighed and measured individually, and euthanized for sampling of brain, gill, liver, kidney and muscle. The oxidative stress biomarkers, thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and non-protein thiols groups (NPSH), were determined. Growth parameters were not affected by the diet containing L. alba EO. As for biomarkers of oxidative stress, lipoperoxidation (LPO) evaluated through TBARS and LOOH was reduced by the EO in the gills, liver, kidney and muscle of silver catfish; no effect was observed in the brain. The diet with the EO improved the activity of antioxidant enzymes: SOD, CAT, GPx, GST and NPSH levels in the brain; SOD, GR and GST in the gills; CAT, GR and NPSH levels in the liver; CAT, GR and NPSH levels in the kidney; and SOD, GPx and NPSH levels in the muscle. These results indicate that L. alba EO does not interfere with growth, decreases LPO levels and increases antioxidant enzymes activities in most tissues evaluated, and thus may be added to silver catfish diet to increase the antioxidant response.
Com a intensificação do cultivo, os peixes se tornam mais susceptíveis ao estresse e, por consequência, ao aparecimento de doenças. Para tentar minimizar este problema, os produtores utilizam agroquímicos que, além de prejudicarem o meio ambiente, podem também prejudicar a saúde dos produtores e consumidores. O óleo essencial (EO, do inglês essential oil) da Lippia alba pode ser uma alternativa natural, pois apresenta diversos efeitos que podem reduzir as alterações fisiológicas decorrentes do estresse inerente à aquicultura. Neste estudo foi avaliada a influência de cinco dietas contendo o EO de L. alba (0, 0.25, 0.5, 1.0 e 2.0 mL de EO por kg de dieta) sobre o crescimento e a resposta antioxidante em juvenis de jundiás. Após um período de 60 dias de alimentação, os jundiás foram pesados e medidos individualmente e eutanasiados para amostragem do encéfalo, brânquias, fígado, rim e músculo. Os biomarcadores de estresse oxidativo, substâncias que reagem ao ácido tiobarbitúrico (TBARS), hidroperóxidos lipídicos (LOOH), superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx), glutationa redutase (GR), glutationa-S-transferase (GST) e o conteúdo dos grupos tióis não proteicos (NPSH) foram determinados. A dieta contendo o EO de L. alba não influenciou o crescimento. Quanto aos biomarcadores de estresse oxidativo, o EO diminuiu a lipoperoxidação (LPO) avaliada através do TBARS e dos LOOH nas brânquias, fígado, rim e músculo do jundiá, não mostrando nenhum efeito sobre a LPO no encéfalo. A dieta com o EO aumentou a atividade das enzimas antioxidantes, SOD, CAT, GPx, GST e o conteúdo de NPSH no encéfalo; SOD, GR e GST nas brânquias; CAT, GR e o conteúdo de NPSH no fígado; CAT, GR e o conteúdo de NPSH no rim e SOD, GPx e o conteúdo de NPSH no músculo, em comparação ao grupo controle. Estes resultados indicam que o EO de L. alba não interfere no crescimento, diminui a LPO e aumenta a atividade das enzimas antioxidantes na maioria dos tecidos avaliados, podendo ser adicionado à dieta de jundiás para aumentar a resposta antioxidante.
Di, Maggio Paula. "Dietary lipids and inflammation : chylomicron remnants suppress pro-inflammatory pathways and activate antioxidant defence mechanisms in human macrophages." Thesis, Royal Veterinary College (University of London), 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.618287.
Full textBagatini, Margarete Dulce. "Avaliação da atividade de enzimas que degradam nucleotídeos de adenina e ésteres de colina e estudo do perfil oxidativo em pacientes com cardiopatia isquêmica." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/4422.
Full textIschemic heart disease (IHD) is a major cardiovascular disease. The term ischemia refers to a lack of oxygen due to inadequate perfusion, which results from an imbalance between oxygen supply and demand. The most common cause of myocardial ischemia is atherosclerotic obstructive coronary artery disease caused by rupture or ulceration of atheromatous plaque and subsequent thrombus formation. Platelets are one of the most important blood components that participate in and regulate thrombus formation by releasing active substances such as adenine nucleotides ATP and ADP. Once their action is exerted, the nucleotides are degraded by a group of enzymes called ectonucleotidases. These enzymes are responsible for the hydrolysis of ATP and ADP to AMP, and consequent formation of adenosine, a cardioprotective and anti-inflammatory molecule. Another important anti-inflammatory molecule is acetylcholine (ACh). However, ACh is rapidly hydrolyzed by the enzymes acetylcholinesterase (AChE) and tyrylcholinesterase (BuChE). Following ischemia, an elevated production of reactive oxygen species (ROS) occurs. The imbalance between ROS production and degradation may lead to an increase in oxidative stress. This study aimed to determine the activity of enzymes involved in thromboregulation, such as NTPDase, 5'-nucleotidase, E-NPP and ADA, the activity of enzymes that degrade choline esters: AChE and BuChE, as well as the parameters of oxidative stress in IHD patients and controls. Evaluation of the oxidant system was carried out by lipid peroxidation and carbonyl protein determination, and the enzymatic and nonenzymatic antioxidant defense measurements were performed in total blood, plasma, and serum of IHD patients. Results showed an increase in the NTPDase and 5'-nucleotidase activities as revealed by nucleotides hydrolysis ATP, ADP and AMP. An increase in E-NPP activity was also observed in IHD patients. However, a decrease in ADA activity was observed. Based on the results presented here we suggest that the pathological condition in IHD produced alterations in ectonucleotidase activities as a compensatory organic response, with the objective of maintaining the levels of adenosine, which is a cardioprotective molecule. An increase in the activity of enzymes that degrade choline esters (AChE and BuChE) in IHD patients was observed. Increasing total blood and serum activities of AChE and BuChE enzymes indirectly reflect reduced levels of ACh. The enhancement of local and systemic inflammatory events is observed due to the absence of the negative feedback control exerted by ACh. Regarding oxidant levels, an increase in TBARS and carbonyl protein levels was observed in acute myocardial infarction (AMI) patients when compared to the control group. The same occurred for the activities of the enzymatic antioxidants, superoxide dismutase (SOD), and catalase (CAT). However, a decrease in nonenzymatic antioxidants, such as vitamin C and vitamin E, was observed in AMI patients when compared to control. These results suggest an increase in oxidative stress in AMI, which was probably a result of the ischemic/reperfusion moment, as well as a decrease of antioxidant defenses. Furthermore, the increased antioxidant defense may act as a compensatory mechanism in consequence of the overproduction of ROS after AMI. In conclusion, IHD results in oxidative and inflamatory damages as well as an increase in the organism defenses as a compensatory response.
A cardiopatia isquêmica (CI) é uma das principais doenças cardiovasculares. O termo isquemia refere-se à falta de oxigênio, secundária à perfusão inadequada do miocárdio, que gera desequilíbrio entre a oferta e a demanda deste gás. A causa mais comum de isquemia miocárdica é a doença aterosclerótica obstrutiva das artérias coronárias, causada por ruptura ou ulceração da placa ateromatosa e consequente formação de trombo. As plaquetas são um dos mais importantes componentes do sangue que participam na regulação dos processos tromboembólicos por liberação de substâncias ativas como os nucleotídeos de adenina, ATP e ADP. Uma vez exercida sua ação esses nucleotídeos são degradados por um grupo de enzimas denominadas de ectonucleotidases. Essas são responsáveis pela hidrólise do ATP e ADP até AMP e consequente formação da adenosina, uma molécula cardioprotetora e anti-inflamatória. Outra importante molécula anti-inflamatória é a acetilcolina (ACh). Entretanto, a ACh é rapidamente hidrolisada pelas enzimas acetilcolinesterase (AChE) e butirilcolinesterase (BuChE). Acompanhando a isquemia temos uma produção elevada de espécies reativas de oxigênio (EROs). Um desequilíbrio entre a produção e a degradação de EROs pode levar a um aumento do estresse oxidativo. Neste trabalho determinaram-se a atividade das enzimas envolvidas na tromboregulação: NTPDase, 5 -nucleotidase, E-NPP e ADA, e a atividade de enzimas que degradam ésteres de colina: AChE e BuChE, além dos parâmetros de estresse oxidativo em pacientes cardiopatas e controles. Foi realizada a avaliação do sistema oxidante através da determinação da peroxidação lipídica e da carbonilação protéica e a medida das defesas antioxidantes enzimáticas e não enzimáticas do organismo, em sangue total, plasma e soro destes pacientes. Os resultados demonstraram um aumento na atividade da NTPDase e da 5 -nucleotidase, revelada através da hidrólise dos nucleotídeos ATP, ADP e AMP. Para a enzima E-NPP também foi observado um aumento na sua atividade em pacientes cardiopatas. Entretanto, para a ADA observou-se uma diminuição na atividade. Esses resultados sugerem uma resposta orgânica compensatória do organismo frente ao estado patológico formado, com o objetivo de manter os níveis de adenosina, uma molécula cardioprotetora. Para as enzimas que degradam ésteres de colina foi observado um aumento tanto na atividade da AChE quanto da BuChE em pacientes cardiopatas. Um aumento na atividade sérica e no sangue total da atividade da BuChE e da AChE pode refletir indiretamente níveis reduzidos de ACh que, por sua vez, irá reforçar eventos inflamatórios locais e sistêmicos, devido à ausência do controle de retroalimentação negativa exercido pela ACh. Em relação aos níveis de oxidantes determinados, observou-se um aumento nos níveis de TBARS e proteína carbonil em soro de pacientes com infarto agudo do miocárdio (IAM) quando comparados com o grupo controle. Esse aumento também foi observado para as defesas antioxidantes enzimáticas superóxido dismutase (SOD) e catalase (CAT). Entretanto, observou-se um decréscimo das defesas antioxidantes não enzimáticas como a vitamina C e a vitamina E no soro de pacientes com IAM. Estes dados sugerem um aumento do estresse oxidativo como resultado do momento de isquemia/reperfusão e da diminuição das defesas antioxidantes não enzimáticas. Além disso, o aumento das defesas antioxidantes enzimáticas poderiam agir como um mecanismo compensatório como consequência da superprodução de EROs após o IAM. Concluí-se então, que a CI resulta tanto em danos oxidativos e inflamatórios como mobilização das defesas do organismo para uma resposta compensatória.
D’Avila, Roseane Farias. "Efeito da redução de aporte hídrico e aplicação de radiação UV-C sobre compostos relacionados à qualidade e ao metabolismo de glicosinolatos em brócolis (Brassica oleracea L. var. italica)." Universidade Federal de Pelotas, 2017. http://guaiaca.ufpel.edu.br:8080/handle/prefix/4138.
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Características diversas das habituais durante o cultivo de vegetais e na pós-colheita podem ser reconhecidas como fatores de estresse pelo metabolismo e, dependendo da intensidade, levar ao acúmulo de compostos de defesa, relacionados ao aumento da vida de prateleira e a atividades antioxidantes e anticancerígenas in vivo. Deste modo, o efeito do cultivo de brócolis sob condições de estresse hídrico e da aplicação de radiação UV-C durante a pós-colheita sobre compostos relacionados a atributos sensoriais e funcionais foram analisados durante colheitas realizadas no verão e inverno. O cultivo sob estresse hídrico ocasionou a diminuição do teor de ácido L-ascórbico em todas as amostras, e os teores de glicosinolatos nos brócolis colhidos no verão, o que também ocorreu para clorofila a e carotenoides. No inverno, o estresse hídrico levou ao aumento de glicosinolatos somente após o armazenamento. Observaram-se diferenças significativas pela aplicação de UV-C após sete dias de armazenamento. No verão, a utilização da dose de 7 kJ.m-2 de UV-C resultou no aumento do conteúdo de clorofilas a e b e de carotenoides nos brócolis cultivados sob aporte hídrico regular. A mesma dose, quando aplicada a plantas cultivadas sob estresse hídrico, promoveu aumento significativo apenas de carotenoides e ácido L-ascórbico. O teor de glicosinolatos em brócolis cultivados no verão foi intensificado pelo cultivo sob condições de estresse hídrico combinado com aplicação de 10 kJ.m-2 de UV-C. No inverno, o aumento do teor de glicosinolatos foi observado aplicando a dose de 7 kJ.m-2, e foi acompanhado pela redução da atividade de mirosinases. Em ambos os cultivos conduzidos no inverno, houve um aumento de isotiocianatos quando brócolis cultivados sob estresse hídrico foram tratados com 10 kJ.m-2 de UV-C. Em vista dos resultados, conclui-se que as respostas metabólicas à redução do aporte hídrico e à aplicação de radiação UV-C são diferentes devido à época de cultivo da hortaliça, com exceção do teor do ácido L-ascórbico, que é reduzido pelo cultivo com estresse independentemente da estação.
Characteristics different from the usual ones during the growing and in the post-harvest of vegetables can be recognized as stress factors by the metabolism and, depending on the level, lead to the accumulation of defense compounds, related to the increase of the shelf life and to the antioxidant and anticancer activities in vivo. Thus, the effect of broccoli cultivation under water stress and of the application of UV-C radiation during post-harvest on compounds related to sensorial and functional attributes were analyzed during summer and winter harvests. The cultivation under water stress caused a decrease in the L-ascorbic acid content in all the samples, and the glycosinolate content in the broccoli harvested in the summer, which also occurred for chlorophyll a and carotenoids. In winter, water stthe pigments presented opposite patterns between the years analyzed, which also occurred with the isothiocyanates, compounds derived from glucosinolates. The stress led to the increase of glucosinolates only after storage. Significant differences were observed by application of UV-C after seven days of storage. In the summer, the use of the 7 kJ.m-2 UV-C dose resulted in increased content of chlorophyll a and b and carotenoids in broccoli grown under regular water intake. The same dose, when applied to the plants grown under water stress, promoted a significant increase only of carotenoids and L-ascorbic acid. The glucosinolates content in broccoli grown in summer was intensified by the cultivation under water stress conditions combined with the application of 10 kJ.m-2 of UV-C. In the winter, the glucosinolates content increase was observed by applying the 7 kJ.m-2 dose, and it was accompanied by a reduction in myrosinase activity. In both cultures conducted in winter, there was an increase in isothiocyanates when broccoli cultivated under water stress were treated with 10 kJ.m-2 of UV-C. In view of the results, it is concluded that the metabolic responses to the reduction of the water supply and to the application of UV-C radiation are different due to the season of cultivation of the vegetable, except for the L-ascorbic acid content, which is reduced by the cultivation with water stress regardless of the season.
Roberts, Blaine R. "Structural studies of the antioxidant defense enzymes : copper, zinc superoxide dismutase and alkyl hydroperoxide reductase flavoprotein /." Connect to this title online, 2007. http://hdl.handle.net/1957/5054.
Full textXu, Chenping. "The effects of solar ultraviolet-B on the proteome and antioxidant defense systems in soybean leaves." College Park, Md. : University of Maryland, 2007. http://hdl.handle.net/1903/6762.
Full textThesis research directed by: Natural Resource Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Peixoto, Luanna Fernandes. "Avaliação do efeito protetor do extrato bruto hidroalcoólico das folhas de Eugenia dysenterica DC. sobre a neurotoxicidade induzida pelo alumínio." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/6134.
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Made available in DSpace on 2016-09-06T13:53:45Z (GMT). No. of bitstreams: 2 Dissertação - Luanna Fernandes Peixoto - 2015.pdf: 3025683 bytes, checksum: bbc78b7fe8fdd447275a7d8f73fd84b6 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-12-15
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
incidence of neurodegenerative disease (ND) is increasing with the world population aging. Among them, Alzheimer's disease (AD) is the most common of dementia in the elderly population. The AD has been linked to oxidative stress resulting in neurodegenerative disorders, such as the impairment of the antioxidant and cholinergic systems. AChE inhibitors drugs are a treatment option used for AD. However, until now, the drug treatment only temporary attenuates the AD symptoms and new drug targets, as the medicinal plants, are necessary for a better treatment of this disease. Eugenia dysenterica DC (Myrtaceae), popularly known as cagaita, is a native plant from the Cerrado region of Brazil. It is used in the folk medicine to treat diarrhea, jaundice and diabetes. Data from literature reported the presence of phenolic compounds, such as flavonoids and tannins, in the leaves of E. dysenterica. Thus, the aim of this study was to evaluate the neuroprotective effect of crude hydroalcoholic extract of E. dysenterica leaves (HEED), using a model of neurotoxicity induced by aluminium in mice and that causes similar cellular alterations of that observed in the Alzheimer’s disease. The results showed the HEED increased the mice performance in the passive avoidance test, showing the reversion of the cognitive damage promoted by aluminium. In addition, the HEED reduced the neuronal lipid peroxidation and restored the activity of superoxide dismutase (SOD), catalase (CAT) and acetylcholinesterase (AChE) enzymes in mice brain. The histological analysis showed the HEED decreased the incidence of neuronal death by necrosis. Taken together, the results here obtained suggest that the antioxidant properties of HEED are the responsible for its neuroprotective effect.
A incidência de doenças neurodegenerativas (DN) vem aumentando com o envelhecimento populacional. Dentre as DN a doença de Alzheimer (DA) é a forma mais comum de demência na população idosa. Um dos fatores envolvidos no desenvolvimento da DA é o estresse oxidativo neuronal que pode resultar em diversas desordens neurodegenerativas, como o comprometimento dos sistemas antioxidante e colinérgico. Um dos tratamentos utilizados para esta doença são os fármacos inibidores de acetilcolinesterase (AChE) porém, as terapias disponíveis apenas atenuam temporariamente os sintomas. Nesse sentido, novas terapias são necessárias para o tratamento da DA e o estudo de plantas pode ser uma fonte para obtenção de novas opções terapêuticas. Eugenia dysenterica DC (Myrtaceae), popularmente conhecida como cagaita, é uma planta encontrada em região de Cerrado, utilizada na medicina popular para tratar doenças diarreicas, icterícia e diabetes. Dados da literatura relatam a presença de compostos fenólicos, como flavonoides e taninos, nas folhas de E. dysenterica., substâncias descritas como potenciais antioxidantes e anticolinesterásicos. Dessa forma, o objetivo deste trabalho foi avaliar o efeito neuroprotetor do extrato bruto hidroalcoólico das folhas de Eugenia dysenterica (EHED) em camundongos, em um modelo de neurotoxicidade induzida por alumínio. O EHED aumentou o tempo de latência na memória de curta e longa duração no teste esquiva passiva, demonstrando a reversão do prejuízo cognitivo promovido pelo alumínio. Os testes chaminé e campo aberto demonstraram que não houve comprometimento na atividade locomotora dos animais. As análises histológicas demonstraram que o tratamento com EHED diminuiu a incidência da morte neuronal por necrose causada pelo AlCl3. Nos ensaios bioquímicos, observou-se que o EHED foi capaz de reduzir a lipoperoxidação e restaurar a atividade das enzimas antioxidantes superóxido dismutase (SOD) e catalase (CAT). Além disso, o EHED foi capaz de restaurar a atividade da AChE, revertendo os danos causados pelo AlCl3. Em conclusão, os resultados obtidos são sugestivos de que o EHED apresenta atividade neuroprotetora por apresentar propriedades antioxidantes, inibindo os efeitos deletérios centrais promovidos pelo alumínio e que se assemelham às alterações celulares descritas para a Doença de Alzheimer.
Murphy, Kelsey E. "BBB-bypassing polysaccharide mini-GAGR activates the neuronal Nrf2- mediated antioxidant defense system for the treatment of Alzheimer’s disease." University of Toledo Health Science Campus / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=mco1576192220098119.
Full textMelendez, Juan Andres. "The effects of cellular quiescence on the antioxidant defense enzymes of bovine embryonic lung fibroblasts: a survey." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/52088.
Full textMaster of Science
Bazito, Olivia Domingues. "Estresse oxidativo e bioluminescência nos fungos Gerronema viridilucens e Mycena lucentipes." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-03092012-144815/.
Full textReactive Oxygen Species (ROS) are normally produced during the metabolism of aerobic organisms. Ligninolitic fungi also produce these oxidizing species also during the lignin degradation process. The bioluminescent species Gerronema viridilucens and Mycena lucentipes were studied aiming to establish a correlation between the temporal profiles of bioluminescence, cellular viability and antioxidant defense enzymes and ligninolitic enzymes in mycelium and fruiting bodies. Chemical toxicants such as metals and phenols were here found to affect light emission, cellular viability, antioxidant defenses and cellular respiration enzymes when administered to G. viridilucens, thereby attesting a metabolic connection between bioluminescence inhibition and fungal oxidative damage. Different species of fungi exhibit different characteristics linked to light emission and antioxidant defenses. Differences in light emission displayed by different species do not resume to fruiting bodies, but the light profile and intensity can also vary in the mycelia. This may explain the irreproducibility of the light profile from M. lucentipes, differently to that observed with G. viridilucens. The cellular viability of both species varies with time, G. viridilucens profile being similar to the time course of bioluminescence. The enzymatic data pointed to higher activities in mycelium than in fruiting bodies, probably due to a main reproductive function of the latter, whereas the metabolic activities are prevalent in the mycelium. Ligninolytic enzymes exhibit low activities in the extracts of fungus samples, probably because they are extracellular degradation enzymes. The inhibition effect of phenols and metals (copper and cadmium) on mycelium viability reinforces the notion that cellular oxidative damage hampers bioluminescence emission. Redox active (copper) and heavy metals (cadmium) were found to display higher impact on antioxidant defenses than phenols (phenol and 2,4,6-trichlorophenol), which are expected to be promptly metabolized and excluded by principally glutathione S-transferase (GST). Notably, a metabolic correlation between bioluminescence inhibition and antioxidant defenses was unveiled by the present work. Regarding the metals, glutathione was found to be a crucial antioxidant, both to eliminate peroxides when in the presence of copper, and to act as a cadmium chelating agent. Under normal conditions, the bioluminescence system, the antioxidant defenses and the cellular respiration sets cooperate through the common demand of reducing power of NAD(P)H. Under chemical stress, the NAD(P)H flux would be deviated from bioluminescence, to principally sustain the antioxidant defenses and cellular respiration, essential for the protection, maintenance and reproduction of the organism.