Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met een samenvatting in het Nederlands.

Orientador: Antonio Condino Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-04T23:42:56Z (GMT). No. of bitstreams: 1 Gomez_LinaAndrea_D.pdf: 4776023 bytes, checksum: a1c947f4c3db64220a2153a255069581 (MD5) Previous issue date: 2005 / Resumo: A NADPH oxidase das células fagocíticas é um sistema enzimático encarregado da produção de espécies reativas do oxigênio, as quais são essenciais durante a resposta imune inata contra uma grande variedade de microorganismos como bactérias e fungos. Um dos principais componentes deste sistema é a proteína citosólica p67PHOX codificada pelo gene NCF2 localizado no braço longo do cromossomo 1. Mutações no gene NCF2 resultam em uma das formas autossômicas recessivas da doença granulomatosa crônica (DGC), uma imunodeficiência primária caracterizada por infecções graves e recorrentes. Recentemente descrevemos mudanças nucleotídicas em alguns pacientes deficientes de p67PHOX onde aparentemente essas alterações não foram responsáveis pelo fenótipo, mas que poderiam modificar de alguma forma a expressão do gene. Para determinar se essas alterações correspondem a polimorfismos gênicos, analisamos sua ocorrência na população normal. A primeira substituição é uma transição C ? T na posição -23 da região 5' reguladora do gene. Dos 100 sujeitos avaliados, 67% foram homozigotos para o alelo C, 32% foram heterozigotos e só 1% foram homozigotos para o alelo T. A segunda mudança nucleotídica corresponde à transição A->G na posição -21 da região 3' terminal do íntron 10 (IVS10-21A?G), essa substituição foi analisada em 114 indivíduos dos quais 41% foram homozigotos para A, 49% foram heterozigotos e 24% homozigotos para G. Esses dois polimorfismos estão localizados dentro de seqüências necessárias para o início da transcrição (C?T at -23) e para a formação do splicing (IVS10-21A?G) e por isto podem alterar a expressão do gene p67PHOX, e conseqüentemente diminuir a atividade do sistema NADPH oxidase. Na análise da seqüência com o polimorfismo no intron 10 (IVS10-21A->G), observamos espécies anormais de mRNA nos indivíduos sadios. Nos genótipos analisados algumas moléculas de RNAm não possuem o exon 11. O efeito funcional do polimorfismo -23C/T no gene p67PHOX foi analisado medindo a atividade da luciferase entre construtos, contendo toda a região promotora com o alelo T e com o alelo C, mas não se observaram diferenças / Abstract: The NADPH oxidase of phagocytic cells is an enzymatic system that through the production of reactive oxygen species is essential for the innate immune response against a variety of bacteria and fungi. One of its essential components is pfyf"0*, a 67-kDa cytosolic protein encoded by the NCF2 gene located in the long arm of chromosome 1. Varied mutations involving the NCF2 gene result in an autosomal recessive form of chronic granulomatous disease (CGD), a primary immunodeficiency characterized by severe and recurrent infections. We have recently described different nucleotide changes in some p67-^jAor-deficient patients that apparently were not responsible for the CGD phenotype, but they could modify to some extent gene expression. To determine if two of these changes corresponded to genetic polymorphisms, we analyzed their occurrence in healthy donors. The first substitution corresponded to C-"T transition at position -23 of the 5' regulatory region of the gene. Among 100 evaluated subjects, 67% were homozygous for the allele containing C, 32% were heterozygous, and 1% were homozygous for T. The second nucleotide change corresponded to A >G transition in position -21 of the 3' end of intron 10 (TVSlf>-21A-"G). This substitution was analyzed in 114 subjects: 41% were homozygous for A, 49% were heterozygous, and 24% were homozygous for G Both polymorphisms are located within sequences necessary for initiating gene transcription (C-"T at -23) and for RNA splicing (IVS10-21A->G). Therefore, they may alter 067¿°^ gene expression and consequently decrease the activity of NADPH oxidase system. The sequence analysis for the polymorphism located in the intron 10 (TVS 10-21 A -Kr) show generation of the abnormal mRNA species in normal individuals; some molecules of the mRNA do not contain the intron 11 in all subject genotypes. The functional effect of the -23 07 polymorphism in the p67-PHOX was evaluated measuring luciferase activity of the T allelic p67-PHOX promoter and C allelic promoter, but no differences were observed / Doutorado / Saude da Criança e do Adolescente / Doutor em Saude da Criança e do Adolescente

The ultimate goal in the field of metabolic engineering is improving cellular processes in a rational manner using engineering design principles and molecular biology techniques. The syntheses of several industrially useful compounds are cofactor-dependent. The reducing equivalent NADPH is required in several enzymatic reactions leading up to the synthesis of high-value compounds like polymers, chiral alcohols, and antibiotics. However, it’s a highly costly compound with limited intracellular availability. This study focuses on the genetic manipulation of a whole-cell system using the two transhydrogenase isoforms pntAB and udhA. Two model systems are used: 1) the production of (S)-2-chloropropionate and 2) the production of poly(3-hydroxybutyrate). Results suggest that the presence of udhA increases product yield and NADPH availability while the presence of pntAB has the opposite effect. A maximum product yield of 1.4 mole-product/mole-glucose was achieved aerobically in a pntAB-deletion strain with udhA overexpression, a 150% improvement over the wild-type control strain.

Diss. (sammanfattning) Stockholm : Karol. inst., 2006. / Härtill 4 uppsatser.

Thesis (Ph. D.)--Cornell University, January, 2009. / Vita. Includes bibliographical references (leaves 147-166).

Würzburg, Univ., Diss., 2004.

Orientador: Valdecir Farias Ximenes / Coorientador: Luiz Marcos da Fonseca / Banca: Maria Luiza Zeraik / Banca: Iêda Maria Marinez Paino / Banca: Daniel Rinaldo / Banca: Iracilda Zeppone Carlos / Resumo: Inúmeras patologias têm a sua gênese e/ou progressão relacionadas à produção desregulada de intermediários oxidantes. O complexo multienzimático NADPH oxidase é um dos componentes de maior relevância neste contexto, pois é uma das principais fontes de ânion superóxido no organismo animal. Sendo expresso em inúmeros tecidos, incluindo leucócitos e células do tecido endotelial, o desenvolvimento de inibidores eficientes deste complexo enzimático poderá significar uma nova terapêutica para o tratamento de doenças inflamatórias crônicas. Com objetivo de explorar a relação entre a estrutura molecular, as propriedades químicas e atividades biológicas, utilizamos o éster fenetílico do ácido cafeico (CAPE) como inibidor do complexo enzimático NADPH oxidase e comparamos sua eficácia com o seu precursor ácido cafeico e os derivados, éster fenetílico do ácido cinâmico e o ácido clorogênico, correlacionando-os a respeito a sua hidrofobicidade, propriedades redox e inibição do complexo NADPH oxidase em leucócitos ativados. A hipótese seria de que um aumento da hidrofobicidade provocado pela esterificação do ácido cafeico poderia facilitar o seu acesso à membrana celular e assim alterar seu efeito como possível inibidor de NADPH Oxidase. Os resultados, em ensaios in vitro, mostraram que as alterações na hidrofobicidade não provocaram alterações significativas no potencial de oxidação e potencial antioxidantes dos compostos testados. Quando testados em leucócitos ativados (modelos ex vivo),... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Several diseases have their genesis and / or progression related to unregulated production of oxidants intermediates. The multienzymatic complex NADPH oxidase is one of the most important components in this context because it is a major source of superoxide anion in animal organisms. It is expressed in numerous tissues, including leukocytes and endothelial tissue cells. Developing effective inhibitors of this enzyme complex may indicate a new therapy for the treatment of chronic inflammatory diseases. Several studies have described numerous anti-inflammatory properties attributed to caffeic acid phenethyl ester (CAPE), an active component found in propolis. In order to explore the relationship between the molecular structure, chemical properties and biological activities, we used CAPE to inhibit the enzyme complex NADPH oxidase and compare its efficacy with the its precursor caffeic acid and derivatives, phenethyl ester of cinnamic acid and chlorogenic acid, correlating them with regard to hydrophobicity, redox properties and inhibition of NADPH oxidase complex on activated leukocytes. The hypothesis was that an increase of hydrophobicity caused by the esterification of caffeic acid could facilitate access to cell membranes and thereby alter its effect as a possible inhibitor of NADPH oxidase. The results (in vitro), showed that the changes in hydrophobicity did not provoke significant changes in the oxidation potential and antiradical potency of the tested compounds. But whe... (Complete abstract click electronic access below) / Doutor

No description available.

Nous avons étudié les propriétés cardioprotectrices de l’hémine, un composé hémique inducteur de l’hème oxygénase-1 (HO-1), dans un modèle, in vivo d’hypertension rénovasculaire « Two- kidney, one clip (2K1C) » chez le rat, et dans un modèle cellulaire de cardiomyocytes de rat stimulés par angiotensine II.L’HO-1 est une enzyme inductible qui dégrade l’hème en monoxyde de carbone, biliverdine/bilirubine, et libérant les ions Fe3+. Ces effets anti-inflammatoires, antioxydants, anti-apoptotiques et anti-prolifératifs sont de plus en plus connus et étudiés. Le stress oxydant jouerait un rôle majeur dans les pathologies de dysfonctionnement endothélial, d’hypertension et pourrait être à l’origine de phénomènes inflammatoires, fibrotiques et apoptotiques. Dans un premier temps nous avons à partir d’un modèle chirurgical d’hypertension rénovasculaire caractérisé les effets de l’hémine sur le développement de la fibrose, le stress oxydatif et l’activation de la NADPH oxydase cardiaque en comparaison à un traitement anti-hypertenseur de référence, le losartan. Dans un second temps, nous avons cherché à caractériser les voies de signalisation intracellulaires impliquées dans cette cardioprotection en utilisant un modèle cellulaire de cardiomyocytes stimulés par angiotensine II. / No summary available

Reactive oxygen species (ROS), and the resulting oxidative stress caused by these species, have long been attributed to be one of the causes for aging and age related disorders. NADPH, the reduced form of nicotinamide adenine dinucleotide phosphate (NADP), provides a critical and essential buffer against cellular toxicity due to ROS. NADPH is one of the cells most powerful reducing agents, capable of regenerating other endogenous antioxidants such as glutathione from its oxidized form, glutathione disulfide. Consequently, it is hypothesized that declining NADPH levels with age results in a depletion in cellular capacity to respond to ROS induced damage, further accelerating the aging process. To study the importance of NADPH on the aging process as well as the molecular mechanisms involved, lifespan assays were performed using knockdown of various enzymes involved in the production of NADPH in Caenorhabditis elegans. Preliminary results indicate declining NADPH levels do have an effect on expected longevity. More interesting however, is a possibly important distinction between cytoplasmic and mitochondrial enzymes involved in the production of NADPH. These preliminary results suggest the existence of a previously undescribed molecular mechanism that is potentially important to the aging process. However, further experiments and analysis are required to further elucidate these mechanisms and to confirm preliminary findings.