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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Influência da qualidade de diferentes tipos de arroz e inibidores de proteinases no rendimento e na virulência de conídios do fungo entomopatogênico Metarhizium anisopliae (Mestch.) Sorokin (Ascomycota: Hypocreales) / Influence of quality of different types of rice and proteinase inhibitors on yield and virulence of conidia of the entomopathogenic fungus Metarhizium anisopliae (Mestch.) Sorokin (Ascomycota: Hypocreales)

Janayne Maria Rezende 01 February 2010 (has links)
Com o intuito de gerar subsídios para melhoria do processo de produção de Metarhizium anisopliae, o presente estudo teve como principais objetivos, determinar os efeitos de inibidores de proteinases de soja no crescimento vegetativo, esporulação e virulência do fungo e comparar a produção, viabilidade e virulência dos conídios produzidos em diferentes tipos de arroz e aditivos. A adição de 5 g.L-1 de inibidores de proteinases semi-purificados de soja ou 0,5 g.L-1 de inibidor purificado do tipo Kunitz no meio de cultura ME resultou em grande aumento na esporulação (de duas a 75 vezes) sem afetar a viabilidade dos conídios de quatro isolados (ESALQ-1037, IBCB348, E9, F20) de M. anisopliae. A presença destes inibidores de proteinases também alterou a morfologia dos conídios produzidos em ME. Os mecanismos responsáveis por estas alterações fisiológicas não foram determinados, mas provavelmente estejam associados à ação anti-nutricional, diminuindo a absorção protéica e estimulando a esporulação. Os conídios produzidos no meio com adição de 0,5 g.L-1 de inibidor de proteinase do tipo Kunitz ou com 2,5 g.L-1 de albumina de soro bovino e no meio BDA apresentaram virulência superior aos conídios produzido no meio ME sem inibidores. Quando o inibidor de proteinase do tipo Kunitz foi adicionado à suspensão de conídios do fungo antes da pulverização de lagartas de Diatraea saccharalis, a eficiência de controle foi 35,1%, inferior ao apresentado pelos demais tratamentos sem a presença deste inibidor. Nos estudos para determinação dos melhores tipos de arroz para produção de M. anisopliae, tentou-se correlacionar à produção de conídios com características destes substratos como valor nutricional, teor de resíduos de agrotóxicos e densidade de microorganismos. O arroz parboilizado foi responsável pela maior produção de conídios (4,38 x 109 conídios.g-1). Este tipo de arroz apresentou teor de proteína bruta menor do que a maioria dos arrozes e o maior teor de umidade (41,3% após a autoclavagem). Além disto, os grãos após autoclavagem ficaram menos gelatinosos e mais soltos, o que facilita o processo de produção do fungo. Enquanto que os arrozes dos tipos brancos polidos, canjicão e integral ficaram pegajosos e formaram grumos, o que provavelmente deve acarretar em menor superfície de desenvolvimento para o fungo. O segundo melhor arroz, o canjicão, com produção de 3,42 x 109 conídios.g-1, teve a maior quantidade de fungos contaminantes nos grãos crus. Quantidades intermediárias de conídios foram produzidas pelos arrozes branco polido irrigado, de terras altas e orgânico. O integral foi o que resultou na menor quantidade de conídios (1,53 x 109 conídios.g-1), sendo o mais rico em minerais, proteína bruta e extrato etéreo. Nenhum dos aditivos (farelo de soja, grãos de soja partidos, extrato de soja, peptona de soja, inibidores de proteinases de soja semipurificados e purificado do tipo Kunitz, polpa cítrica e levedura) resultou em aumento na produção de conídios em comparação com o arroz parboilizado sem aditivos. Os conídios produzidos em todos os arrozes e aditivos apresentam viabilidade superior a 99%. As vantagens da utilização do arroz parboilizado levando-se em consideração custo, facilidade de manuseio e produtividade são discutidas. / In order to optimize the production process of Metarhizium anisopliae, the present study aimed to determine the effects of soybean proteinase inhibitors on growth, sporulation and virulence of the fungus and to compare yield, viability and virulence of M. anisopliae conidia produced in different types of rice and additives. The addition of 5 g.L-1 of semi-purified soybean proteinase inhibitor or 0.5 g.L-1 of Kunitz-type inhibitor purified on the culture medium ME resulted in large increases in sporulation (two to 75 times) without affecting the viability of conidia of four M. anisopliae isolates (ESALQ-1037, IBCB348, E9, F20). The presence of proteinase inhibitors altered morphology of conidia produced in ME. Mechanisms responsible for these physiological changes in the fungus have not been determined, but it is probably associated to an anti-nutritional action, reducing the absorption of protein and stimulating sporulation. Spores produced in the medium with the addition of 0.5 g.L-1 Kunitz-type inhibitor purified or 2.5 g.L-1 of bovine serum albumin (BSA) and PDA medium showed higher virulence of conidia produced in ME without inhibitors. When the Kunitz-type inhibitor was added to conidial suspension of the fungus before spraying larvae of Diatraea saccharalis, control efficiency was 35.1% lower than that presented in other inhibitor-free treatments. In the studies aiming to determine the best types of rice for production of M. anisopliae, we tried to correlate production of conidia with characteristics of these substrates such as nutritional content, pesticide residues and density of microorganisms. The parboiled rice was responsible for greater production of conidia (4.38 x 109 conidia.g-1). This type of rice showed crude protein content lower than most rice and the highest moisture content (41.3% after autoclaving). Besides that, grains became less gelatinous and loose after autoclaving, and these feature favored fungus production. While types of polished white, brown rice and course (broken) rice grain were sticky and formed clumps, providing a smaller area for fungus development. The second best rice, course rice grain, with production of 3.42 x 109 conidia.g-1, had the highest amount of fungal contaminants in raw grains. Intermediate amounts of conidia were produced by white irrigated polished rice, upland rice and organic rice. The brown rice was the kind that resulted in fewer conidia (1.53 x 109 conidia.g-1), being the richest in minerals, protein and lipids. None of the additives (soybean meal, soybean parties, soy extract, soy peptone, semi-purified soybean proteinase inhibitor, Kunitz-type inhibitor purified, citrus pulp and yeast) resulted in increased production of conidia compared to parboiled rice without additives. Conidia produced in all types of rice and additives presented viability greater than 99%. The advantages of the use of parboiled rice taking into consideration the cost, easy handling and productivity are discussed.
32

Etude pluridisciplinaire de peptides liés à la maladie d'Alzheimer: de la protéine précurseur de l'amyloïde (APP) aux oligomères de beta-amyloïde et aux inhibiteurs de gamma-sécrétase / Multidisciplinary study of Alzheimer's disease-related peptides: from amyloid precursor protein (APP) to amyloid beta-oligomers and gamma-secretase modulators

Itkin, Anna 14 May 2012 (has links)
La maladie d'Alzheimer (AD) est un désordre neurodégénératif progressif et la forme la plus commune de démence. A l’heure actuelle, il n'y a aucun remède et la maladie est toujours fatale. Une des caractéristiques histopathologiques de l'AD est la présence de dépôts protéiques, les plaques amyloïdes, dans le cerveau. Ces plaques sont formées par les peptides amyloïdes β (Aβ) de 40 et 42 résidus, qui sont les produits de clivage par des protéases de la protéine précurseur de l’amyloïde (l'APP). L'élucidation de certains des processus clés dans la cause et le développement de l'AD est une étape cruciale pour le développement de traitements nouveaux et efficaces.<p><p>Les propriétés conformationnelles du segment transmembranaire (TM) de l’APP peuvent affecter sa protéolyse par la γ-sécrétase. Ces propriétés ne sont pas encore clairement établies. Afin de comprendre le rôle des variations structurelles du TM dans le traitement de l'APP, des détails structurels des peptides APP_TM4K, chimiquement synthétisés, ont été étudiés dans la bicouche lipidique en utilisant la réflexion totale atténuée par spectroscopie infrarouge à transformée de Fourier (ATR-FTIR) et la résonance magnétique nucléaire à l’état solide (ssNMR). Tandis que la structure secondaire globale du peptide APP_TM4K est hélicoidale, une hétérogénéité conformationnelle et orientée a été observée pour le site de clivage γ et, dans une plus faible mesure, pour le site de clivage ζ. Ces variabilités conformationnelles autour des sites de clivage γ et ζ peuvent avoir des implications importantes dans le mécanisme de clivage et donc dans la production d’Aβ. Il a été aussi démontré que la dernière glycine dans le motif de dimérisation GxxxG est transmembranaire. Ceci peut impliquer que la dimérisation via ce motif pourrait servir d’ancrage et conférer une orientation transmembranaire stable au segment transmembranaire de l’APP.<p><p>Le peptide amyloïde β est directement lié à la maladie d’Alzheimer. Partant de sa forme monomérique, l’Aβ s'agrège pour produire en final des fibrilles et aussi de manière transitoire toute une gamme d'oligomères, ces derniers étant la plupart neurotoxiques. Une dérégulation de l’homéostasie du Ca2+ dans le cerveau vieillissant et dans des troubles neurodégénératifs joue un rôle crucial dans de nombreux processus et contribue au dysfonctionnement et à la mort cellulaire. Nous avons postulé que le calcium peut permettre ou accélérer l'accumulation d'Aβ. Le modèle d'accumulation d'Aβ (1-40) et celui d'Aβ (1-40) E22G, un peptide amyloïde portant la mutation arctique qui cause une apparition prématurée de la maladie, ont été comparé. Nous avons constaté qu'en présence de Ca2+, l’Aβ (1-40) forme de préférence des oligomères semblables à ceux formés par l’Aβ (1-40) E22G avec ou sans Ca2+, tandis qu'en absence de Ca2+ l'Aβ (1-40) s’agrège sous forme de fibrilles. Les ressemblances morphologiques entre oligomères ont été confirmées par microscopie de force atomique. La distribution des oligomères et des fibrilles dans des échantillons différents a été détectée par électrophorèse sur gel suivie d’une analyse par Western blot, dont les résultats ont été confirmés par des expériences de fluorescence à la thioflavine T. Dans les échantillons sans Ca2+, l’ATR-FTIR révèle la conversion des oligomères en feuillets β antiparallèles en la conformation caractéristique des fibrilles en feuillets β parallèles. En général, ces résultats nous ont ameré à conclure que les ions calcium stimulent la formation d'oligomères d'Aβ (1-40), qui sont impliqués dans la pathogénèse d'AD.<p><p>Malgré les progrès énormes obtenus dans la compréhension de la maladie (AD), il reste un défi majeur, celui du développement de médicaments nouveaux et efficaces. Afin d’obtenir des éclaircissements sur le mécanisme d'action de deux nouveaux puissants modulateurs de la γ-sécrétase - le benzyl-carprofen et le sulfonyl-carprofen dans la bicouche lipidique, la technique de RMN à l’état solide a été employée. Précédemment, les dérivés du carprofen ont été localisés dans des membranes de lipides par des expériences de diffusion (scattering) des neutrons. Les contraintes déterminées à partir des expériences de ssNMR ont permis d’affiner leurs positions et d’obtenir une orientation précise dans la double couche lipidique. Ces résultats combinés indiquent que le mécanisme probable de modulation du clivage par la γ-sécrétase est une interaction directe des carprofènes avec le domaine TM de l’APP. Une telle interaction, empêcherait à la formation de dimères d'APP, dimérisation nécessaire au clivage séquentiel par la γ-sécrétase, diminuant ou réduisant ainsi énormément la production d’Aβ, tout particulièrement d’Aβ42.<p><p>Les résultats de ce travail apporte de nouvelles informations sur les processus clés impliqués dans l'AD; Production de l'Aβ à partir de l'APP, formation des oligomères d'Aβ et mécanisme d'action potentiel de molécules thérapeutiques. Nous pensons que ces résultats pourront permettre une meilleure compréhension de la maladie et pourront aider dans la conception de nouveaux médicaments contre cette maladie.<p><p>Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and the most common form of dementia. There is no cure and the disease is fatal. One of the characteristic histopathological markers of AD is the presence of proteinaceous deposits, amyloid plaques, in the brain. These plaques are formed by the amyloid β-peptides (Aβ) 40- and 42-residue-long, which are protease cleavage products of the amyloid precursor protein (APP). Elucidation of some of the key processes in the cause and the development of AD is crucial for the development of new and efficient treatments.<p><p>Conformational properties of the transmembrane (TM) segment of APP may affect its proteolytic processing by γ-secretase. These properties have not been definitely established. In addressing the role of structural variations of the TM sequence in APP processing, structural details of the chemically synthesized APP_TM4K peptides within the membrane bilayers were studied using Attenuated total reflection Fourier transform spectroscopy (ATR-FTIR) and solid-state nuclear magnetic resonance (ssNMR) techniques. While the overall secondary structure of the APP_TM4K peptide is an α-helix, conformational and orientational heterogeneity was observed for the γ-cleavage site and, to a smaller extent, for the ζ-cleavage site. Evidence for the conformational variability around γ- and ζ-cleavage sites may have important implications for the cleavage mechanism and hence for the Aβ production. It was also found that the last glycine within the sequence of GxxxG motifs is in the transmembrane orientation, implying that dimerization via these motifs may act as an anchor, confining the TM dimer to the stable transmembrane orientation. <p><p>Amyloid β-peptide is directly linked to AD. Starting from its monomeric form, Aβ aggregates into fibrils and / or oligomers, the latter being the most neurotoxic. Dysregulation of Ca2+ homeostasis in aging brains and in neurodegenerative disorders plays a crucial role in numerous processes and contributes to cell dysfunction and death. Here we postulated that calcium may enable or accelerate the aggregation of Aβ. The aggregation pattern of Aβ(1-40) and of Aβ(1-40)E22G, an amyloid peptide carrying the Arctic mutation that causes early onset of the disease, were compared. We found that in the presence of Ca2+, Aβ(1-40) preferentially formed oligomers similar to those formed by Aβ(1-40)E22G with or without added Ca2+, whereas in the absence of added Ca2+ the Aβ(1-40) aggregated to form fibrils. Morphological similarities of the oligomers were confirmed by contact mode atomic force microscopy (AFM) imaging. The distribution of oligomeric and fibrillar species in different samples was detected by gel electrophoresis and Western blot analysis, the results which were further supported by thioflavin T fluorescence experiments. In the samples without Ca2+, Fourier transform infrared spectroscopy revealed conversion of oligomers from an anti-parallel β-sheet to the parallel β-sheet conformation characteristic of fibrils. Overall, these results led us to conclude that calcium ions stimulate the formation of oligomers of Aβ(1-40), that have been implicated in the pathogenesis of AD. <p><p>Despite the tremendous progress in understanding AD, there remains the challenge of the development of new and efficient drugs. In order to shed light onto the mechanism of action of two new potent γ-secretase modulators -- benzyl-carprofen and sulfonyl-carprofen within lipid bilayers, ssNMR technique was employed. Using neutron scattering experiments it was previously found that sulfonyl-carprofen and benzyl-carprofen partition into the headgroup region of the lipid bilayer. The orientational constraints derived from the ssNMR experiments refined their position into precise orientation. Combined, these results indicate that carprofen-derivatives can directly interact with the region of APP that mediates dimerization. Such interaction, would interfere with proper APP-dimer formation, which is necessary for the sequential cleavage by γ-secretase, diminishing or greatly reducing Aβ42 production.<p><p>Results obtained during this work shed new light onto some of the key processes in AD: Aβ production from APP, formation of Aβ oligomers and insights into the mechanism of action of potential therapeutics. We believe that these results will promote a better understanding of the disease and will help in future drug design.<p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
33

Efeito do inibidor  de proteinase de origem vegetal EcTI, sobre a inflamação pulmonar alérgica crônica em camundongos Balb/c / Effect of proteinase inhibitor of plant origin EcTI in an experimental model of chronic allergic pulmonary inflammation in Balb/c mice

Rodrigues, Adriana Palmeira Dias 21 March 2016 (has links)
INTRODUÇÃO: A prevalência de asma tem crescido e a maioria dos pacientes com asma grave não obtém o controle total dos sintomas com as terapias disponíveis, fazendo-se necessária a busca por novas alternativas terapêuticas. Inibidores de proteinases têm sido estudados como tratamento de processos inflamatórios, dentre eles o Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) OBJETIVO: Avaliar se o inibidor de proteinase EcTI modula a hiperresponsividade brônquica à metacolina, inflamação, remodelamento e estresse oxidativo nas vias aéreas e septos alveolares em um modelo experimental de inflamação pulmonar alérgica crônica. MÉTODOS: Vinte e quatro camundongos Balb/c machos, entre seis e sete semanas de vida, pesando em media 25 g foram divididos em quatro grupos: C (controle), OVA (sensibilizados com ovalbumina, 50 ug intraperironeal (i.p) nos dias 0 e 14 e desafiados nos dias 22, 24, 26, 28); C+EC (controle tratados com EcTI (2 mg/kg/i.p) nos dias 22 a 28); OVA+EC (sensibilizados e desafiados com ovalbumina e também tratados com EcTI (2 mg/kg -i.p) nos dias 22 a 28). No dia 29, foram realizadas realizadas: (i) hiperresponsividade à metacolina e obtidas as respostas máximas de resistência e elastância do sistema respiratório; (ii) análise histopatológica do pulmão para quantificação de eosinófilos, fibras colágenas e elásticas nas vias aéreas (VA) e nos septos alveolares (SA); e (iii) imunohistoquímica para quantificação de células positivas para IFN-y, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-beta, iNOS, NF-kB e fração de volume de isoprostano nas VA e nos SA. Uma semana após o dia 29 foi realizada a técnica de anafilaxia cutanea passiva(PCA) para quantificar IgE e IgG1. A significância foi considerada quando p < 0,05. RESULTADOS: Houve aumento de todos os parâmetros avaliados no grupo OVA em relação ao grupo controle (p < 0,05). Houve atenuação da resposta máxima de Rrs e Ers no grupo OVA+EC comparado as grupo OVA (p < 0,05). O tratamento com EcTI nos animais sensibilizados atenuou o número de eosinófilos, células positivas para IL-4, IL-5, IL-13,IFN-y, iNOS, MMP-9, TIMP-1, NF-kB e TGF-beta e fração de volume de isoprostano, fibras colágenas e elásticas nas vias aéreas e nos séptos alveolares quando comparado ao grupo OVA (p < 0,05).Houve reaçao de PCA nos animais sensibilizados com ovalbumina. CONCLUSÃO: EcTI atenuou a hiperresponsividade brônquica, a inflamação, o remodelamento e o estresse oxidativo nesse modelo experimental de inflamação pulmonar alérgica crônica. Embora sejam necessários mais estudos, esse inibidor pode ser considerado uma futura ferramenta farmacológica para o tratamento de asma / BACKGROUND: The number of cases of asthma has grown in recent decades. People who have severe asthma are likely to have more attacks and are at greater risk of a fatal attack, which propose to keep up global attention and keep approaching for advances in asthma care. Proteinase inhibitors of vegetable origin have been studied as a modulator of inflammatory responses and diseases. Among these inhibitors is Enterolobium contortisiliquum Trypsin Inhibitor (EcTI). AIMS: To evaluate the effects of EcTI in pulmonary mechanical, eosinophilic recruitment, inflammatory cytokines, remodeling of extracellular matrix and oxidative stressin an experimental model of chronic allergic pulmonary inflammation. METHODS: Twenty-four young adult male pathogen-free mice BALB/c (6-7 weeks old, 25-30g) were divided into 4 groups: C (control), OVA (sensitized with ovalbumin, 50 ug intraperitoneal (i.p), on days 0 and 14 and challenged with ova 1%, on days 22, 24, 26, 28); C+EC (control treated with EcTI- 2 mg/kg/i.p. from days 22 to 28); OVA+EC (sensitized and challenged with ovalbumin and treated with EcTI (2 mg/kg/i.p) from days 22 to 28). At day 29, we performed: (i) Bronchial hyperresponsiveness to methacholine and obtained the maximum response of resistance (Rrs) and elastance (Ers) of the respiratory system; (ii) lung histopathological analysis by morphometry to quantify eosinophils, collagen and elastic fibers volume fraction in airways; and (iii) immunohistochemistry to quantify IFN-y, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-, iNOS, NF-kB positive cells and isoprostane volume fraction in airways. One week after the day 29 we performed PCA technique to quantify IgE and IgG1 antibodies. Significance was considered at p < 0.05. RESULTS: The EcTI treatment in the ovalbumin-sensitized animals attenuated the maximal response of resistance and elastance of respiratory system after methacholine, the number of eosinophils, IL-4, IL-5, IL-13, IFN-y, NF-kB and iNOS-positive cells, isoprostane, elastic, collagen volume fraction, MMP-9, TIMP-1 and TGF-beta-positive cells compared to OVA group (p < 0.05). PCA was positive in sensitized animals. CONCLUSION: EcTI attenuates bronchial hyperresponsiveness, inflammation, remodeling and oxidative stress activation in this experimental asthma mice model. Although more studies are needed this inhibitor may be considered a future pharmacological tool for the treatment of asthma
34

Efeito do inibidor  de proteinase de origem vegetal EcTI, sobre a inflamação pulmonar alérgica crônica em camundongos Balb/c / Effect of proteinase inhibitor of plant origin EcTI in an experimental model of chronic allergic pulmonary inflammation in Balb/c mice

Adriana Palmeira Dias Rodrigues 21 March 2016 (has links)
INTRODUÇÃO: A prevalência de asma tem crescido e a maioria dos pacientes com asma grave não obtém o controle total dos sintomas com as terapias disponíveis, fazendo-se necessária a busca por novas alternativas terapêuticas. Inibidores de proteinases têm sido estudados como tratamento de processos inflamatórios, dentre eles o Enterolobium contortisiliquum Tripsin Inhibitor (EcTI) OBJETIVO: Avaliar se o inibidor de proteinase EcTI modula a hiperresponsividade brônquica à metacolina, inflamação, remodelamento e estresse oxidativo nas vias aéreas e septos alveolares em um modelo experimental de inflamação pulmonar alérgica crônica. MÉTODOS: Vinte e quatro camundongos Balb/c machos, entre seis e sete semanas de vida, pesando em media 25 g foram divididos em quatro grupos: C (controle), OVA (sensibilizados com ovalbumina, 50 ug intraperironeal (i.p) nos dias 0 e 14 e desafiados nos dias 22, 24, 26, 28); C+EC (controle tratados com EcTI (2 mg/kg/i.p) nos dias 22 a 28); OVA+EC (sensibilizados e desafiados com ovalbumina e também tratados com EcTI (2 mg/kg -i.p) nos dias 22 a 28). No dia 29, foram realizadas realizadas: (i) hiperresponsividade à metacolina e obtidas as respostas máximas de resistência e elastância do sistema respiratório; (ii) análise histopatológica do pulmão para quantificação de eosinófilos, fibras colágenas e elásticas nas vias aéreas (VA) e nos septos alveolares (SA); e (iii) imunohistoquímica para quantificação de células positivas para IFN-y, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-beta, iNOS, NF-kB e fração de volume de isoprostano nas VA e nos SA. Uma semana após o dia 29 foi realizada a técnica de anafilaxia cutanea passiva(PCA) para quantificar IgE e IgG1. A significância foi considerada quando p < 0,05. RESULTADOS: Houve aumento de todos os parâmetros avaliados no grupo OVA em relação ao grupo controle (p < 0,05). Houve atenuação da resposta máxima de Rrs e Ers no grupo OVA+EC comparado as grupo OVA (p < 0,05). O tratamento com EcTI nos animais sensibilizados atenuou o número de eosinófilos, células positivas para IL-4, IL-5, IL-13,IFN-y, iNOS, MMP-9, TIMP-1, NF-kB e TGF-beta e fração de volume de isoprostano, fibras colágenas e elásticas nas vias aéreas e nos séptos alveolares quando comparado ao grupo OVA (p < 0,05).Houve reaçao de PCA nos animais sensibilizados com ovalbumina. CONCLUSÃO: EcTI atenuou a hiperresponsividade brônquica, a inflamação, o remodelamento e o estresse oxidativo nesse modelo experimental de inflamação pulmonar alérgica crônica. Embora sejam necessários mais estudos, esse inibidor pode ser considerado uma futura ferramenta farmacológica para o tratamento de asma / BACKGROUND: The number of cases of asthma has grown in recent decades. People who have severe asthma are likely to have more attacks and are at greater risk of a fatal attack, which propose to keep up global attention and keep approaching for advances in asthma care. Proteinase inhibitors of vegetable origin have been studied as a modulator of inflammatory responses and diseases. Among these inhibitors is Enterolobium contortisiliquum Trypsin Inhibitor (EcTI). AIMS: To evaluate the effects of EcTI in pulmonary mechanical, eosinophilic recruitment, inflammatory cytokines, remodeling of extracellular matrix and oxidative stressin an experimental model of chronic allergic pulmonary inflammation. METHODS: Twenty-four young adult male pathogen-free mice BALB/c (6-7 weeks old, 25-30g) were divided into 4 groups: C (control), OVA (sensitized with ovalbumin, 50 ug intraperitoneal (i.p), on days 0 and 14 and challenged with ova 1%, on days 22, 24, 26, 28); C+EC (control treated with EcTI- 2 mg/kg/i.p. from days 22 to 28); OVA+EC (sensitized and challenged with ovalbumin and treated with EcTI (2 mg/kg/i.p) from days 22 to 28). At day 29, we performed: (i) Bronchial hyperresponsiveness to methacholine and obtained the maximum response of resistance (Rrs) and elastance (Ers) of the respiratory system; (ii) lung histopathological analysis by morphometry to quantify eosinophils, collagen and elastic fibers volume fraction in airways; and (iii) immunohistochemistry to quantify IFN-y, IL-4, IL-5, IL-13, MMP-9, TIMP-1, TGF-, iNOS, NF-kB positive cells and isoprostane volume fraction in airways. One week after the day 29 we performed PCA technique to quantify IgE and IgG1 antibodies. Significance was considered at p < 0.05. RESULTS: The EcTI treatment in the ovalbumin-sensitized animals attenuated the maximal response of resistance and elastance of respiratory system after methacholine, the number of eosinophils, IL-4, IL-5, IL-13, IFN-y, NF-kB and iNOS-positive cells, isoprostane, elastic, collagen volume fraction, MMP-9, TIMP-1 and TGF-beta-positive cells compared to OVA group (p < 0.05). PCA was positive in sensitized animals. CONCLUSION: EcTI attenuates bronchial hyperresponsiveness, inflammation, remodeling and oxidative stress activation in this experimental asthma mice model. Although more studies are needed this inhibitor may be considered a future pharmacological tool for the treatment of asthma
35

Subcellular Localization and Partial Purification of Prelamin a Endoprotease: An Enzyme Which Catalyzes the Conversion of Farnesylated Prelamin a to Mature Lamin A

Kilic, Fusun, Johnson, D A., Sinensky, M. 30 April 1999 (has links)
The nuclear lamina protein, lamin A is produced by proteolytic cleavage of a 74 kDa precursor protein, prelamin A. The conversion of this precursor to mature lamin A is mediated by a specific endoprotease, prelamin A endoprotease. Subnuclear fractionation indicates that the prelamin A endoprotease is localized at the nuclear membrane. The enzyme appears to be an integral membrane protein, as it can only be removed from the nuclear envelope with detergent. It is effectively solubilized by the detergent n-octyl-beta-D-glucopyranoside and can be partially-purified (approximately 1200-fold) by size exclusion and cation exchange (Mono S) chromatography. Prelamin A endoprotease from HeLa cells was eluted from Mono S with 0.3 M sodium chloride as a single peak of activity. SDS-PAGE analysis of this prelamin A endoprotease preparation shows that it contains one major polypeptide at 65 kDa and smaller amounts of a second 68 kDa polypeptide. Inhibition of the enzyme activity in this preparation by specific serine protease inhibitors is consistent with the enzyme being a serine protease.

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