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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.
471

Abnormal cAMP-dependent protein kinase activity leads to bone tumors in adult mice but this depends on the PKA subunit expressions / CUHK electronic theses & dissertations collection

January 2015 (has links)
Protein kinase A (PKA) is an important enzyme inside the body; it is responsible for phosphorylation of gene regulatory elements and thus regulation of gene expression inside the nucleus. Malfunction of PKA affects transcriptional and translational levels of cell signaling ligands, leading to abnormal activity of various signaling pathways. PKA holoenzyme is composed of two regulatory and two catalytic subunits; four main regulatory subunit isoforms (R1α, R1β, R2α and R2β) and four main catalytic subunit isoforms (Cα, Cβ, Cγ and Prkx) of PKA have been identified. Mutations in these subunits lead to altered total PKA activities and PKAT-I to PKAT-II ratios, leading to diseases both in human and mice. These diseases include Carney Complex (CNC), fibrous dysplasia (FD) and Cushing syndrome. We studied the effect of PKA subunit mutations on intracellular PKA activities, PKAT-I to PKAT-II ratios, and bone and adrenal gland phenotypes in transgenic mouse models. Firstly, we generated whole-body transgenic mice single or double heterozygous for PKA regulatory subunits. Tail vertebral bone lesions including osteosarcomas, osteochondromas and osteochondrosarcomas were found in these mice and we found that mutations in different PKA subunits affect bone lesion formation, new bone generation, and bone organization and mineralization in mouse tail vertebrae. Elevated Cβ subunit expression in Parkar1a+/-Prkar2a+/- and Prkar1a+/-Prkar2b+/-double heterozygous mice leads to a less severe vertebral bone lesion phenotype, an increased osteogenic activity and a better bone regeneration activity. We then studied mice with tissue specific knock out of Prkar1a, the gene coding for type I regulatory subunit, specifically in adrenal cortex (AdKO). AdKO mice developed pituitary-independent Cushing syndrome with increased PKA activity. They also demonstrated increased plasma corticosterone levels resistant to dexamethasone suppression. Dietary treatment of both mice with bone lesions and mice with adrenal lesions with COX2 inhibitor Celecoxib led to partial rescue of phenotypes; this is due to inhibition of the positive feedback loop between PKA signaling and inflamasome pathway at COX2 induction level by Celecoxib. / 蛋白激酶A(PKA)是人體中重要的蛋白酶, 它通過燐酸化基因調控元件來實現對細胞核內基因表達的調節。PKA異常影響細胞內信號傳遞因子的基因轉錄和蛋白翻譯水平,從而導致各細胞信號通路的異常活動。PKA全酶由兩個調節亞基和兩個催化亞基組成,目前已經發現的有四個調節亞基 (R1α, R1β, R2α 和R2β) 以及四個催化亞基(Cα, Cβ, Cγ和Prkx)。發生在這些亞基中的基因突變會改變總的PKA活動水平,PKA-I 和PKA-II的比例,在人類和實驗鼠中引起疾病。這些疾病包括卡尼綜合症 (CNC),骨纖維性發育不良(FD)和庫欣綜合症。我們在轉基因鼠模型中研究PKA亞基突變對細胞中PKA總活性, PKA-I和PKA-II比例的影響,以及由此帶來的骨和腎上腺表型的改變和病變。我們首先製造了有一個或兩個PKA亞基雜合性缺失的全身轉基因鼠。在這些轉基因鼠中,我們發現了包括骨肉瘤,骨軟骨瘤和骨軟骨肉瘤在內的尾椎骨病變。研究發現在不同PKA亞基中的基因變異對實驗鼠尾椎骨病變的發生,新骨的形成和骨的結構和纖維化均有影響。在Prkar1a+/-Prkar2a+/-和Prkar1a+/-Prkar2b+/-實驗鼠中我們發現了較高的Cβ催化亞基表達,這兩個基因型因此具有更輕度的骨病變和更強的骨再生能力。我們繼續研究了在腎上腺中敲除了標記PKA 第一調節亞基的Prkar1a基因的實驗鼠 (AdKO)。AdKO實驗鼠中產生了與垂體無關的庫欣綜合症,並伴隨PKA活性的增加。它們還表現出耐地塞米松抑制的血漿皮質酮水平增加。對骨病變或腎上腺病變的實驗鼠通過飲食進行COX2抑制劑塞來昔布的治療可以部分緩解病變表型。這是由對PKA和炎性體的正反饋機制在COX2誘導步驟的抑制造成的。 / Liu, Sisi. / Thesis Ph.D. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 115-130). / Abstracts also in Chinese. / Title from PDF title page (viewed on 09, September, 2016). / Detailed summary in vernacular field only.
472

Estudos sobre vacinologia e evolução do vírus da cinomose canina

Budaszewski, Renata da Fontoura January 2017 (has links)
O vírus da cinomose canina (CDV) é um importante patógeno de cães domésticos e carnívoros selvagens. A infecção pelo CDV é relevante a nível mundial e está associada com alta morbidade e mortalidade. Em diversos países a cinomose é considerada controlada pelo uso de vacinas, no entanto, no Brasil ainda é endêmica, principalmente devido ao grande número de animais não domiciliados. Além disso, surtos em cães e várias espécies de animais silvestres ocorrem com frequência, dizimando populações ameaçadas. As vacinas vivas atenuadas são seguras para cães, mas seu uso não é aconselhado em espécies altamente suscetíveis à infecção pelo CDV. Também os relatos de surtos de cinomose em cães supostamente vacinados levantam a hipótese de que as vacinas disponíveis no mercado podem não ser eficientes frente a algumas cepas de campo. Com o objetivo de gerar dados acerca dos mecanismos de evolução do CDV e desenvolver e testar a eficácia de uma vacina bivalente inativada contra o vírus da raiva (RABV) e CDV a presente tese será apresentada na forma de dois artigos científicos. Ainda, um artigo de revisão sobre os modelos animais utilizados para obtenção de informações sobre o vírus do sarampo utilizando a infecção de CDV em furões e cães foi publicada e será apresentada na presente tese. No primeiro artigo, foi analisada a ocorrência de recombinação homóloga em genomas de CDV e detectou-se oito possíveis vírus recombinantes, incluindo um evento de recombinação entre uma cepa de campo e uma cepa vacinal atenuada, sugerindo que o uso de vacinação com vírus vivo atenuado pode influenciar a evolução do CDV. No segundo trabalho, uma vacina recombinante bivalente inativada baseada em RABV expressando as glicoproteínas do envelope do CDV, hemaglutinina e proteína de fusão, mostrou-se eficiente na proteção contra infecção por CDV em furões quando utilizado um protocolo prime/boost. Finalmente, foi publicada uma revisão de literatura sobre os modelos animais utilizados para obtenção de informações sobre a patogênese do vírus do sarampo utilizando a infecção com o vírus da cinomose. / Canine distemper virus (CDV) is an important pathogen of domestic dogs and wild carnivores. CDV infection is globally relevant and it is associated with high morbidity and mortality. In several countries, distemper is considered controlled by vaccination, however, in Brazil it is still endemic, mainly due to the large number of non-domiciliated animals. In addition, outbreaks in dogs and various species of wild animals occur frequently, decimating threatened populations. Live attenuated vaccines are safe for dogs, but their use is not advised in species that are highly susceptible to CDV infection. Also, reports of canine distemper in supposedly vaccinated dogs raise the hypothesis that commercially available vaccines may not be effective against some wild type strains. In order to investigate the mechanisms of CDV evolution and to develop and assess the efficacy of an inactivated bivalent vaccine against rabies virus and CDV, this thesis will be presented in the form of two scientific papers. Furthermore, a review article on the animal models used to gain information on measles virus using CDV infection in ferrets and dogs has been published and will be presented in this thesis. In the first paper, the occurrence of homologous recombination in CDV genomes was analyzed and eight possible recombinant viruses were detected, including a recombination event between a wild type strain and an attenuated vaccine strain, suggesting that the use vaccines based on attenuated live virus may influence CDV evolution. In the second study, an inactivated bivalent recombinant vaccine based on RABV expressing CDV envelope glycoproteins, hemagglutinin and fusion protein, proved to be effective in protecting against CDV infection in ferrets when using a prime/boost protocol. Finally, a literature review was published on the animal models used to obtain information on the pathogenesis of measles virus using infection with canine distemper virus.
473

De la dysfonction endothéliale à la dysfonction immunitaire dans l’hypertension artérielle pulmonaire : nouvelles cibles d’innovation thérapeutique / From endothelial dysfunction to immune dysfunction in pulmonary arterial hypertension : novel therapeutical targets

Huertas, Alice 02 October 2013 (has links)
L’hypertension artérielle pulmonaire (HTAP) est une maladie grave caractérisée par une obstruction progressive des artères pulmonaires de petit calibre, conduisant à une augmentation des résistances vasculaires pulmonaires et, à terme, à une défaillance cardiaque droite et au décès du patient. La vasoconstriction, le remodelage vasculaire et la dysfonction endothéliale pulmonaire sont autant de facteurs qui contribuent au développement et à la progression de la maladie. Plusieurs arguments sont également en faveur d’une hypothèse de désordres immunologiques, voire autoimmuns, dans la physiopathologie de l’HTAP. Malgré ces données, le lien entre endothélium pulmonaire et système immunitaire dans cette maladie restent peu connus. Ce travail de thèse a donc eu pour objectif d’étudier et mieux comprendre la nature et les conséquences d’une communication aberrante entre cellules endothéliales pulmonaires et système immunitaire dans la pathogénèse de l‘HTAP, afin d’identifier de nouvelles cibles thérapeutiques. Pour cela, nous avons analysé le rôle de la dysfonction endothéliale dans la régulation de deux processus de la dysfonction immunitaire : l’autoimmunité pour la réponse adaptative d’une part, et la sécrétion de cytokines en ce qui concerne la réponse innée d’autre part. A travers ce travail de thèse, nous avons mis en évidence l’existence d’une communication aberrante entre endothélium pulmonaire et système immunitaire dans l’HTAP et montré que l‘endothélium pulmonaire jouait un rôle primordial dans le contrôle des réponses adaptatives, en régulant la fonction des lymphocytes T régulateurs via la leptine, et dans la participation active à la réponse innée, en acquérant un phénotype pro-inflammatoire. Cette meilleure compréhension du rôle de la dysfonction endothéliale dans la dérégulation du système immunitaire présente dans l’HTAP pourrait aider au développement de nouvelles stratégies thérapeutiques dans cette maladie. / Pulmonary arterial hypertension (PAH) is a severe disease characterized by a progressive obstruction of small pulmonary arteries, leading to an increase in pulmonary vascular resistance and ultimately right heart failure and death. Vasoconstriction, vascular remodeling and pulmonary endothelial dysfunction contribute to the disease development and progression. Increasing evidence are also suggesting the importance of immune disorders, such as autoimmunity, in PAH pathophysiology. Despite these data, the link between pulmonary endothelium and immune system is still unclear. The objective of this work was to investigate and elucidate the nature and the consequences of an aberrant communication between pulmonary endothelial cells and immune system in PAH pathogenesis, in order to identify new therapeutical targets. Therefore, we analyzed the role of endothelial dysfunction in the control of two types of altered immune responses: autoimmunity for the adaptive response and cytokine secretion for the innate response. In this work, we highlighted the existence of an aberrant communication between pulmonary endothelium and immune system in PAH and showed that pulmonary endothelium played a key role in the control of adaptive responses, by regulating regulatory T lymphocyte function in a leptin-dependent manner, and by actively participating to the innate responses through a pro-inflammatory phenotype. A better understanding of the role of endothelial dysfunction in PAH immune system dysregulation may help to the development of new therapeutical strategies for this disease.
474

Papel do fósforo e do paratormônio na progressão da doença renal crônica / Role of phosphorus and parathyroid hormone in the progression of chronic kidney disease

Magalhães, Andréa Olivares 18 January 2008 (has links)
Introdução: Os mecanismos envolvidos na progressão da doença renal crônica (DRC) independentemente de sua etiologia, não estão totalmente esclarecidos. O controle do fósforo(P) sérico é uma meta essencial a ser alcançada no tratamento de pacientes com DRC. Inicialmente, a importância deste controle era atribuída a participação do P na patogênese do hiperparatireoidismo secundário. Atualmente sabe-se que a hiperfosfatemia aumenta a mortalidade desses pacientes. Distúrbios do metabolismo mineral participam da progressão da DRC, porém os mecanismos envolvidos na fisiopatologia, não foram esclarecidos. Objetivo: Avaliar o efeito isolado da sobrecarga de P e de diferentes concentrações de paratormônio (PTH) na progressão da doença renal em ratos urêmicos. Materiais e métodos: Ratos Wistar machos adultos foram submetidos à paratireoidectomia (PTX) e nefrectomia 5/6 (NX), a seguir implantamos mini bombas osmóticas com diferentes concentrações de PTH ou veículo. Realizamos 2 experimentos. Experimento 1: Animais que receberam dietas com diferentes conteúdos de P (1,2% ou 0,2% dieta rica e pobre respectivamente).Estes animais receberam infusão fisiológica de PTH (1-34 rat PTH 0,022/100g/h). No experimento 2, os animais receberam as mesmas dietas porém infusão elevada de PTH (1-34 rat PTH 0,11/100g/h). Os animais controles (grupo controle e sham) foram os mesmos para os dois experimentos. A alimentação dos animais foi controlada por pair feeding e a pressão arterial caudal (PAC) foi aferida semanalmente. Após 8 semanas os animais foram sacrificados.Creatinina corrigida por peso, P, cálcio,PTH e hematócrito foram analisados. No tecido renal quantificamos a fibrose intersticial (FI), esclerose glomerular(EG) e o número de células apoptóticas. Avaliamos, no tecido renal a expressão de ED-1, alfa-actina, angiotensina II e TGF-beta. Resultados: Animais NX que receberam infusão fisiológica de PTH e dieta rica em P desenvolveram mais FI, EG, e maior expressão de ED-1. Os animais que receberam infusão elevada de PTH apresentaram maiores níveis tensionais. Foi demonstrado uma correlação entre os marcadores inflamatórios (TGF-beta e Angio II) confirmando a associação entre estes fatores no processo de fibrogênese. O número de células apoptóticas foi maior nos grupos NX que receberam PTH em concentração elevada. Conclusão: Neste estudo, a sobrecarga de P atuou na progressão da DRC ativando principalmente vias inflamatórias e o excesso de PTH agiu piorando a hipertensão arterial. / Introduction: The mechanisms involved in the progression of chronic kidney disease (CKD), regardless of its etiology, have yet to be well elucidated. Serum phosphorus control is an essential target to be achieved in the treatment of patients with CKD. Initially, the importance of this control was attributed to the participation of phosphorus (P) in the pathogenesis of secondary hyperparathyroidism. It is currently known that hyperphosphatemia increases mortality in these patients. Disturbances of the mineral metabolism participate in the progression of CKD; however, the mechanisms involved in pathophysiology remain unclear. Objective: To evaluate the isolated effect of phosphorus overload and different PTH concentrations in the progression of kidney disease in uremic rats. Materials and methods: Adult male Wistar rats were submitted to parathyroidectomy and nephrectomy 5/6; subsequently, we implanted mini osmotic pumps with different concentrations of PTH or vehicle. We carried out 2 experiments. Experiment 1: Animals who received diets with different P contents (1.2% or 0.2% rich and poor diet, respectively). These animals received infusion of PTH solution (1-34 rat PTH 0.022/100g/h). In experiment 2, the animals received the same diets; however, with high PTH infusion (1-34 rat PTH 0.11/100g/h). Control animals (control group and sham) were the same for both experiments. Food intake of the animals was controlled by pair feeding, and caudal artery pressure (CAP) was measured weekly. After 8 weeks, the animals were sacrificed. Creatinine, phosphorus, calcium, PTH and hematocrit were analyzed. Interstitial fibrosis (IF), glomerular sclerosis (GS), and number of apoptotic cells were quantified in the renal tissue. ED-1 expression, alfa-actin, angiotensin II and TGF-beta were evaluated in the renal tissue, as well. Results: NX animals that received infusion of PTH solution and P-rich diet developed more IF and GS, and greater ED-1 expression. The animals that received high PTH infusion presented higher tensional levels. A correlation was demonstrated between inflammatory markers (TGF-beta and Angio II) confirming the association between these factors in the fibrogenesis process. The number of apoptotic cells was higher in NX groups that received PTH in high concentration. Conclusion: In this study, phosphorus overload acted in the progression of CKD activating inflammatory pathways; in addition, excess PTH worsened arterial hypertension.
475

Investigation on the relationship between protein aggregation and neurodegeneration of polyglutamine disease in an inducible drosophila model.

January 2007 (has links)
Wong, Siu Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 129-141). / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (Chinese version) --- p.iii / Acknowledgements --- p.iv / List of Abbreviations --- p.v / List of Tables --- p.vii / List of Figures --- p.viii / Chapter 1. --- INTRODUCTION / Chapter 1.1 --- Neurodegenerative disorders - a brief overview --- p.1 / Chapter 1.2 --- Polyglutamine diseases --- p.2 / Chapter 1.3 --- Microscopically visible polyglutamine protein aggregates and its relation to toxicity --- p.7 / Chapter 1.4 --- Polyglutamine protein conformers and their relation to toxicity --- p.10 / Chapter 1.5 --- Modeling polyglutamine diseases in Drosophila / Chapter 1.5.1 --- GAL4/UAS spatial transgene expression system in Drosophila --- p.14 / Chapter 1.5.2 --- Temporal control of GAL4/UAS transgene expression system in Drosophila --- p.16 / Chapter 1.5.3 --- Drosophila as a model to study human pathologies --- p.19 / Chapter 1.5.4 --- Drosophila as a model to study polyglutamine diseases --- p.21 / Chapter 1.6 --- Aims of study --- p.26 / Chapter 2. --- MATERIALS AND METHODS / Chapter 2.1 --- Drosophila culture and manipulation / Chapter 2.1.1 --- Drosophila culture --- p.27 / Chapter 2.1.2 --- Phenotypic examination of adult external eye degeneration --- p.27 / Chapter 2.1.3 --- Pseudopupil assay of adult retinal degeneration and observation of green fluorescent protein in adult eyes --- p.28 / Chapter 2.2 --- Semi-quantitative Reverse Transcription-Polymerase Chain Reaction / Chapter 2.2.1 --- RNA extraction from adult Drosophila heads --- p.30 / Chapter 2.2.2 --- DNase treatment of extracted RNA --- p.31 / Chapter 2.2.3 --- Reverse transcription-Polymerase Chain Reaction (RT-PCR) --- p.31 / Chapter 2.2.4 --- Agarose gel electrophoresis --- p.33 / Chapter 2.3 --- Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) / Chapter 2.3.1 --- Protein extraction from adult Drosophila heads --- p.33 / Chapter 2.3.2 --- Preparation of SDS-polyacrylamide gel and electrophoresis --- p.34 / Chapter 2.3.3 --- Western blotting --- p.35 / Chapter 2.3.4 --- Immunodetection --- p.36 / Chapter 2.4 --- Immunoprecipitation --- p.38 / Chapter 2.5 --- Filter retardation assay --- p.39 / Chapter 2.6 --- Isolation and solubilization of SDS-insoluble protein --- p.40 / Chapter 2.7 --- Sucrose gradient sedimentation --- p.41 / Chapter 2.8 --- Preparation of Drosophila tissues for immunofluorescence analysis / Chapter 2.8.1 --- Dissection and immunostaining of Drosophila larval imaginal eye discs --- p.42 / Chapter 2.8.2 --- Cryosectioning and immunostaining of adult Drosophila heads --- p.44 / Chapter 2.9 --- Atomic force microscopy --- p.47 / Chapter 2.10 --- Reagents and buffers / Chapter 2.10.1 --- Reagents for Drosophila culture --- p.48 / Chapter 2.10.2 --- Reagents for RT-PCR --- p.52 / Chapter 2.10.3 --- Reagents for SDS-PAGE --- p.54 / Chapter 2.10.4 --- Reagents for immunoprecipitation --- p.57 / Chapter 2.10.5 --- Reagents for filter retardation assay --- p.57 / Chapter 2.10.6 --- Reagents for isolation and solubilization of SDS-insoluble protein --- p.58 / Chapter 2.10.7 --- Reagents for sucrose gradient sedimentation --- p.58 / Chapter 2.10.8 --- Reagents for immunofluorescence --- p.59 / Chapter 3. --- RESULTS / Chapter 3.1 --- Establishment of an inducible transgenic Drosophila model of polyglutamine diseases / Chapter 3.1.1 --- Introduction --- p.60 / Chapter 3.1.2 --- Results / Chapter 3.1.2.1 --- GAL80ts-mediated inducible expression of expanded polyglutamine protein in Drosophila / Chapter 3.1.2.1.1 --- GAL80ts controls GAL4/UAS-mediated polyQ protein expression --- p.61 / Chapter 3.1.2.1.2 --- Inducible expression of SDS-soluble expanded polyglutamine protein --- p.64 / Chapter 3.1.2.1.3 --- Inducible expression of expanded polyglutamine protein accumulates gradually in form of SDS-insoluble protein --- p.66 / Chapter 3.1.2.1.4 --- Inducible expression of expanded polyglutamine protein results in progressive accumulation of microscopically visible aggregates --- p.68 / Chapter 3.1.2.2 --- Inducible expression of expanded polyglutamine protein causes late-onset progressive neuronal degeneration in Drosophila / Chapter 3.1.2.2.1 --- Inducible expression of expanded polyglutamine protein leads to late-onset progressive deterioration of photoreceptor neurons --- p.68 / Chapter 3.1.2.2.2 --- Inducible expression of expanded polyglutamine protein neither causes external eye degenerative phenotype nor disrupts gross retinal morphology despite deterioration of photoreceptor neurons --- p.72 / Chapter 3.1.2.3 --- Co-expression of caspase inhibitor P35 suppresses polyglutamine-induced neuronal degeneration --- p.72 / Chapter 3.1.2.4 --- Co-expression of molecular chaperone Hsp70 suppresses polyglutamine-induced neuronal degeneration --- p.74 / Chapter 3.1.2.5 --- Inducible expression of expanded polyglutamine protein results in biphasic expression of molecular chaperone Hsp70 in Drosophila --- p.76 / Chapter 3.1.3 --- Discussion --- p.76 / Chapter 3.2 --- Involvement of microscopically visible polyglutamine aggregates in neurodegeneration / Chapter 3.2.1 --- Introduction --- p.83 / Chapter 3.2.2 --- Results / Chapter 3.2.2.1 --- Effect of Hsc70-K71S on microscopically visible polyglutamine aggregates and neuronal degeneration / Chapter 3.2.2.1.1 --- Co-expression of Hsc70-K71S reduces the level of microscopically visible polyglutamine aggregates --- p.83 / Chapter 3.2.2.1.2 --- Co-expression of Hsc70-K71S does not alter polyglutamine transgene expression --- p.84 / Chapter 3.2.2.1.3 --- Co-expression of Hsc70-K71S does not modify polyglutamine-induced neuronal degeneration --- p.87 / Chapter 3.2.2.2 --- Microscopically visible polyglutamine aggregates do not correlate with neuronal degeneration --- p.90 / Chapter 3.2.3 --- Discussion --- p.93 / Chapter 3.3 --- Detection of small SDS-insoluble expanded polyglutamine protein species and its association with neurodegeneration / Chapter 3.3.1 --- Introduction --- p.97 / Chapter 3.3.2 --- Results / Chapter 3.3.2.1 --- Accumulation of SDS-soluble expanded polyglutamine protein does not correlate with neuronal degeneration --- p.98 / Chapter 3.3.2.2 --- Identification of small SDS-insoluble expanded polyglutamine protein species / Chapter 3.3.2.2.1 --- Accumulation of total SDS-insoluble expanded polyglutamine protein positively correlates with progressive neuronal degeneration --- p.99 / Chapter 3.3.2.2.2 --- Accumulation of large SDS-insoluble expanded polyglutamine protein does not correlate with neuronal degeneration --- p.99 / Chapter 3.3.2.2.3 --- Accumulation of small SDS-insoluble expanded polyglutamine protein correlates with neuronal degeneration --- p.104 / Chapter 3.3.3 --- Discussion --- p.107 / Chapter 3.4 --- Biophysical characterization of small SDS-insoluble expanded polyglutamine protein species / Chapter 3.4.1 --- Introduction --- p.109 / Chapter 3.4.2 --- Results / Chapter 3.4.2.1 --- Separation of expanded polyglutamine protein species by sucrose gradient sedimentation --- p.110 / Chapter 3.4.2.2 --- Morphological studies of small SDS-insoluble expanded polyglutamine protein species by atomic force microscopy --- p.112 / Chapter 3.4.3 --- Discussion --- p.118 / Chapter 4. --- GENERAL DISCUSSION --- p.124 / Chapter 5. --- CONCLUSION --- p.127 / Chapter 6. --- REFERENCES --- p.129
476

Estudo de derivados n-fenilpiperazínicos candidatos a protótipos de fármacos antipsicóticos de segunda geração / Study of n-phenylpiperazine derivatives candidates to second generation antipsychotic lead compounds

Neves, Gilda Angela January 2009 (has links)
Este trabalho apresenta a continuidade da avaliação farmacológica das substâncias LASSBio-579, LASSBio-580 e LASSBio-581, através de ensaios in vitro e in vivo, em busca de um novo protótipo para o desenvolvimento de novos fármacos antipsicóticos de segunda geração. LASSBio-581 se liga a receptores D2-like (Ki=0,95 μM), 5-HT1A (Ki=1,2 μM) e 5-HT2A (Ki=11 μM) com afinidades moderadas. Esta substância é capaz de reduzir a temperatura corporal de roedores, um efeito provavelmente mediado pela ativação de receptores 5-HT1A, e inibir o desenvolvimento de head-twiches e ear-scratches induzidos pela administração de um antagonista de receptores 5-HT2A. Estes efeitos demonstram a capacidade de LASSBio-581 em modular o sistema serotonérgico in vivo e in vitro. Porém, quanto avaliado em modelos animais preditivos de ação antipsicótica, LASSBio-581 foi inativo. LASSBio-580 também é capaz de se ligar a receptores D2-like (Ki=0,73 μM), 5-HT1A (Ki=0,48 μM) e 5-HT2A (Ki=5,7 μM) com afinidades moderadas. Esta substância não foi capaz de inibir o desenvolvimento do comportamento de escalada nem a redução da temperatura corporal de roedores induzidos por apomorfina, não apresentando potencial atividade antipsicótica nos ensaios realizados. Já LASSBio-579 é capaz de modular três diferentes sistemas neurotransmissores envolvidos na patofisiologia da esquizofrenia: a neurotransmissão dopaminérgica, serotonérgica e glutamatérgica. Esta substância se liga a receptores D2-like (Ki=0,11 μM), 5-HT1A (Ki=0,09 μM) e 5-HT2A (Ki=2,2 μM) com afinidades adequadas para uma molécula protótipo que se liga a múltiplos alvos. Apresenta ação antidopaminérgica in vivo, demonstrada em três modelos animais preditivos de atividade antipsicótica (sintomas positivos): inibição da estereotipia anfetamínica (NEVES et al., 2003), bloqueio do comportamento de escalada induzido por apomorfina e hipotermia apomorfínica. A ação agonista 5-HT1A de LASSBio-579 in vivo foi claramente demonstrada através de ensaios de aferição da temperatura corporal, onde o efeito hipotérmico induzido por esta substância é completamente bloqueado pela pré-administração de WAY 100635. Porém, a habilidade de LASSBio-579 em modular a atividade de receptores 5-HT2A in vivo permanece incerta. Ensaios eletrofisiológicos preliminares demonstraram um aumento da liberação de glutamato induzido por LASSBio-579 que parece ser mediado pela ativação de receptores 5-HT2A, porém comportamentos ou efeitos relacionados a ativação deste sub-tipo de receptor serotonérgico não foram identificados em roedores tratados com LASSBio-579. Além disso, a administração de LASSBio-579 não induziu efeitos catatônicos em camundongos em doses até 12 vezes superiores àquela ativa no modelo do bloqueio do comportamento de escalada induzido por apomorfina. Estes resultados demonstram que a estratégia de planejamento de fármacos baseado na estrutura do ligante empregada neste trabalho se mostrou bem sucedida. LASSBio-579 pode ser considerado um novo protótipo de fármaco antipsicótico de segunda geração, ativo em modelos animais de sintomas positivos da esquizofrenia e com baixo potencial de indução de efeitos motores. Porém, algumas limitações em seu perfil farmacológico pode ser identificadas. A afinidade desta substância por receptores dopaminérgicos e serotonérgicos é considerada moderada e inferior a de antipsicóticos atualmente no mercado. Ainda, LASSBio-579 induziu um prejuízo na coordenação motora em roedores e apresentou um perfil farmacocinético pouco adequado a utilização clinica (CONRADO et al., 2008). Estes dados encorajam a busca de substâncias com um perfil farmacológico superior ao de LASSBio-579. Neste sentido, uma triagem farmacológica de 18 derivados N-fenilpiperazínicos análogos a LASSBio-579 foi realizada. Os resultados obtidos nos ensaios de radioligação a receptores D2-like, 5-HT1A e 5-HT2A foram utilizados na proposição de relações qualitativas entre estrutura química das substâncias e a afinidade apresentada pelos diferentes receptores. A partir dos resultados obtidos in vitro, cinco outras substâncias foram selecionadas para avaliação da potencial atividade frente a sintomas positivos da esquizofrenia no modelo de bloqueio do comportamento de escalada induzido por apomorfina. Neste ensaio, apenas LASSBio-664 apresentou atividade, sem induzir catatonia nos animais. Porém, esta substância também induz um importante prejuízo motor nos animais. Ensaios adicionais são necessários a fim de diferenciar o perfil farmacológico de LASSBio-664 e LASSBio-579. Outro objetivo deste trabalho foi iniciar o desenvolvimento de um modelo animal de sintomas da esquizofrenia. Os resultados obtidos até o momento apontam para a possibilidade do desenvolvimento de um modelo relacionado a sintomas negativos/cognitivos da esquizofrenia baseados na esposição à natação forçada repetida. Foi demonstrado que apenas clozapina e não imipramina é capaz de reverter o aumento de imobilidade ao longo dos dias acarretado pela exposição repetida à natação forçada em roedores. Este dado demonstra uma potencial validade preditiva, o primeiro grau de validação necessário para um novo modelo animal. O efeito de LASSBio-579 também foi avaliado neste procolo experimental. / This study strengthened the pharmacological evaluation of the heterocyclic Nphenylpiperazine derivatives LASSBio-579, LASSBio-580 and LASSBio-581 by means of in vitro and in vivo pharmacological assays searching a new second generations antipsychotic lead compound. LASSBio-581 presented moderate affinitties for D2-like (Ki=0.95 μM), 5-HT1A (Ki=1.2 μM) e 5-HT2A (Ki=11 μM). This compound induced an hypothermic effect in rodents probably mediated by 5-HT1A receptor activation. LASSBio-581 administration inhibited the induction of head-twiches and ear-scratches by a 5-HT2A agonist. These results shown that LASSBio-581 modulates serotonergic neurotransmission in vivo and in vitro. However, it was inactive on animal models predictive of antipsychotic activity. LASSBio-580 presented moderate affinitties for D2-like (Ki=0.73 μM), 5-HT1A (Ki=0.48 μM) e 5-HT2A (Ki=5.7 μM). This compound did not inhibited apomophine-induced climbing nor apomorphine-induced hypothermia. Thus, among the three compounds initially evaluated, LASSBio-579 was the only one that exhibited promising results. This derivative was able to modulate three neurotransmitter systems involved in schizophrenia’s pathophysiology: dopaminergic, serotonergic and glutamateric ones. As a multi-target lead compound, LASSBio-579 presented adequated affinities for D2-like, 5-HT1A and 5-HT2A receptors (Ki D2-like = 0.11 μM, 5-HT1A = 0.093 μM and 5-HT2A = 2.2 μM). Its antidopaminergic in vivo effect was demonstrated in three animal models of positive symptons of schizophrenia: amphetamineinduced stereotypy (NEVES et al., 2003), apomorphine-induced climbing behavior and apomorphine-induced hypothermia. Regarding the serotonergic system, LASSBio-579 was considered a 5-HT1A receptor agonist, since the hypothermia induced by this compound was blocked by WAY 100,635 pre-administration. The ability of LASSBio-579 to modulate 5-HT2A receptors was not fully characterized. Electrophysiological assays demonstrated an increase on synaptic glutamate release induced by LASSBio-579 that may be related to 5-HT2A receptor activation, however this compound did not induce any behavior related to 5-HT2A activation in rodents. In addition, LASSBio-579 did not induce catalepsy in mice at doses 12 folds higher than those active at apomorphine-induced climbing test. Thus, LASSBio-579 represents a new antipsychotic lead compound active in animal models of positive symptoms of schizophrenia and with a mild propensity to induce motor side effects. However, some limitations on LASSBio-579’s pharmacological profile could be identified. The affinity of LASSBio-579 for dopamine and serotonin receptors is moderate and lower than those presented by second generation antipsychotics. Furthermore, this compound induced a mild decrease on locomotion and exploratory behavior, a meaningful motor coordination impairment and presents a limited oral bioavailability and a low brain penetration (CONRADO et al., 2008). Considering this, a pharmacologycal screening of 18 N-phenylpiperazine derivatives were done in order to achieve an optimized analogue of LASSBio-579. Structural features of this molecular scaffold were discussed regarding binding affinity and selectivity for D2-like, 5-HT1A and 5-HT2A receptors. Among the compounds prepared, LASSBio-664 exhibited an adequate binding profile and a potential for schizophrenia positive symptoms treatment without cataleptogenic effects. However, the motor coordination impairment remained. Additional pharmacological characterization of LASSBio-664 is still needed to find differences from LASSBio-579’s profile. Another aim of this study was to start the development of an animal model of schizophrenia symptons. It was shown that clozapine but not imipramine presented an anti-immobility effect in animals repeated exposed to forced swimming. This result points to the usefullness of repeated forced swimming protocol for developing new animal models predictive of antipsychotic action. The effect of LASSBio-579 in this protocol was also evaluated.
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Envolvimento do núcleo leito da estria terminal nos efeitos ansiolíticos do canabidiol / Involvement of the bed nucleus of the stria terminalis in the anxiolytic effects of cannabidiol

Felipe Villela Gomes 26 January 2011 (has links)
O canabidiol (CBD), um componente não-psicotomomético presente na planta Cannabis sativa, induz efeitos ansiolíticos em roedores e humanos após administração sistêmica. Entretanto, poucos estudos foram feitos para identificar as estruturas cerebrais envolvidas nesses efeitos do CBD. Dados prévios do nosso laboratório apontam para um possível envolvimento do núcleo leito da estria terminal (NLET) nos efeitos ansiolíticos do CBD, como evidenciado pelos níveis alterados (reduzidos) de imunorreatividade para proteína c-Fos (marcador de ativação neuronial) em animais tratados com administração sistêmica de CBD no modelo da resposta emocional condicionada (REC) contextual. Os mecanismos de ação pelos quais o CBD produz seus também são ainda pouco compreendidos, mas pode envolver a ativação de receptores 5-HT1A. Assim, o presente trabalho investigou se a administração de CBD diretamente no NLET atenuaria a expressão da REC contextual. Além disso, nós também avaliamos o envolvimento do NLET nos efeitos ansiolíticos do CBD em outros dois modelos animais de ansiedade amplamente utilizados, o labirinto em cruz elevado e o teste do lamber punido de Vogel e, se os efeitos ansiolíticos do CBD envolveriam a ativação local de receptores 5-HT1A. Os resultados mostraram que o CBD reduziu significativamente o tempo de congelamento e atenuou as respostas cardiovasculares induzidas pela re-exposição ao contexto aversivo no modelo da REC contextual. Além disso, o CBD também aumentou a exploração dos braços abertos do LCE, bem como o número de lambidas punidas no teste de Vogel, sugerindo um efeito ansiolítico. Adicionalmente, o CBD não alterou o número de entradas nos braços fechados do LCE e não interferiu no consumo de água ou no limiar nociceptivo, descartando potenciais interferentes nesses dois modelos. Nós também observamos que o pré-tratamento local com WAY100635, um antagonista de receptores 5-HT1A, foi capaz de bloquear os efeitos do CBD injetado no NLET nos três modelos animais utilizados. Logo, estes resultados dão suporte à proposta que NLET está envolvido nos efeitos ansiolíticos do CBD observado após a administração sistêmica, e que este efeito parece envolver a neurotransmissão mediada por receptores 5-HT1A. / Cannabidiol (CBD), a major non-psychotomimetic compound from Cannabis sativa, induces anxiolytic effects in rodents and humans following systemic administration. Despite the brain structures of CBD acts remain poorly understood, previous results from our laboratory suggest that the bed nucleus of the stria terminalis (BNST) may be involved in the anxiolytic effects of CBD, as evidenced by changed levels (decreased) in c-Fos protein expression (a marker of neuronal activation) in animals treated with systemic administration of CBD in the contextual fear conditioning. The mechanisms of CBD effects are still poorly understood but may involve activation of 5-HT1A receptors. Thus, in the present study, we have investigated the anxiolytic-like effects of intra-BNST administration of CBD in rats submitted to contextual fear conditioning. Moreover, we also evaluated the involvement of the BNST in the anxiolytic effects of CBD in other two widely used animal models of anxiety, the elevated plus-maze and the Vogel conflict test, and if these effects are mediated by local activation of 5-HT1A receptors. The results showed that CBD significantly decreased the freezing time and attenuated the cardiovascular responses induced by contextual fear conditioning. Moreover, CBD has also increased the exploration of open arms in EPM, and the number of punished licks in the Vogel test, suggesting an anxiolytic effect. Additionally, the CBD did not alter the number of entries in closed arms of the EPM and did not affect water consumption or pain threshold, eliminating potential interferences of these two models. We also found that local pretreatment with WAY100635, a 5-HT1A receptor antagonist, was able to block the effects of CBD injected into the BNST in the three animal models of anxiety used. Hence, these results support the proposal that BNST is involved in anxiolytic effects of CBD observed after systemic administration, and this effect seems to involve the neurotransmission mediated by 5-HT1A receptors.
478

Indução de tolerância nasal com colágeno tipo V em modelo experimental de esclerodermia / Collagen V- induced nasal tolerance in scleroderma experimental model

Ana Paula Pereira Velosa 08 May 2007 (has links)
Objetivo: Verificar o remodelamento da pele e produção de anticorpos em modelo experimental de esclerodermia em coelhos, após indução de tolerância nasal com colágeno tipo V. Métodos: Coelhas Nova Zelândia (N=12) foram imunizadas com 1mg/ml de colágeno V (Col V) em adjuvante completo de Freund e dois reforços com adjuvante incompleto de Freund. Seis coelhas imunizadas receberam uma dose diária de 25ug de Col V, iniciado via nasal (grupo tolerado) 150 dias do começo das imunizações e seis animais foram somente imunizadas (grupo imunizado). Um grupo imunizado com adjuvante de Freund serviu como controle. Biopsias de pele foram coletadas em 0, 75, 120, 150 e 210 dias e coradas pelo H&E, tricrômico de Masson e Sírius red para analise morfológica e morfométrica. Os colágenos I, III e V, além de TGFbeta e PDGF foram imunomarcados por imunofluorescência. Os soros dos animais foram coletados em 0, 150 e 210 dias para determinar anticorpos anti-colágenos I, III, IV e V e anti-nucleares. Resultados: Os animais imunizados mostraram progressivo decréscimo da derme papilar, atrofia de anexos, aumento no depósito dos colágenos I, III e V e aumento da expressão de TGFbeta e PDGF. Os tolerados apresentaram aumento dos anexos cutâneos e significante diminuição no depósito dos colágenos I, III e V, TGFbeta e PDGF. O grupo de imunizados e de tolerados apresentaram anticorpos anti-colágenos III e IV e antinucleares. Conclusões: A indução de tolerância nasal com Col V diminuiu o remodelamento da pele observado no modelo experimental de esclerodermia e inibiu a síntese de citocinas fibrogênicas. Portanto, a tolerância nasal com Col V pode ser uma opção terapêutica promissora para o controle do remodelamento cutâneo em pacientes com esclerodermia. / Objective: Our aim was to verify the skin remodeling and antibody production in experimental model of scleroderma in rabbits, after induction of tolerance by daily nasal administration of human type V collagen (Col V). Methods: Female New Zealand rabbits (N=12) were immunized with 1mg/ml of Col V in complete Freund\'s adjuvant, followed by more two boosters in incomplete Freund\'s adjuvant. Six immunized rabbits received daily nasal administrating of 25ug of Col V (tolerated group), started 150 days after the first immunization, and the others animals (N=6) were only immunized (immunized group). Finally a group of rabbits immunized with Freund\'s adjuvant served as control. Skin biopsies were collected at 0, 75, 120, 150 and 210 days, and stained with H&E, Masson\'s trichrome and Sirius red for morphological and morphometric analysis. Types I, III and V collagen, TGFbeta and PDGF were immunostained by immunofluorescence. The sera of animals were colleted at 0, 150 and 210 days to determine anti types I, III, IV and V collagen and antinuclear antibodies. Results: The immunized animals showed progressive decrease of papillary dermis, appendages atrophy, increase of types I, III and V collagen deposition and increased expression of TGF-beta and PDGF. The tolerated rabbits presented increase of cutaneous appendages and significant decrease of types I, III and V and TGF-beta and PDGF. Both immunized and tolerated rabbits presented anti types III and IV antibodies and antinuclear antibodies. Conclusions: Col V nasal tolerance reduced skin remodeling in experimental model of scleroderma and inhibited synthesis of fibrotic cytokines. Therefore, the nasal tolerance with type V collagen can be a promising therapeutic option to control the skin remodeling in patients with scleroderma.
479

Efeitos morfológicos, histológicos e moleculares dos moduladores seletivos dos receptores de estrogênios tamoxifeno e raloxifeno na prevenção primária de tumores mamários quimicamente induzidos em ratas / Morphological, histological and molecular effects of SERMs tamoxifen and raloxifene in primary prevention of chemically-induced mammary tumors in rats

Lincon Jo Mori 28 August 2007 (has links)
O câncer de mama é a neoplasia mais comum na população feminina, representando até um terço dos novos diagnósticos de neoplasia nessa população em algumas regiões do mundo. A prevenção primária ou secundária constitui a pedra fundamental no controle do câncer de mama; depende da identificação dos determinantes da doença, em termos de iniciação e promoção. Aproximadamente, 48.930 novos casos de câncer de mama são detectados anualmente no Brasil, tornando-se um sério problema de saúde pública. O objetivo primário deste estudo foi avaliar a ação e diferenças de dois SERMs, tamoxifeno (TAM) e raloxifeno (RAL), na quimioprevenção de tumores mamários quimicamente induzidos em ratas. Foram estudados três grupos homogêneos (DMBA ou 7,12-Dimetilbenzantraceno, TAM e RAL) compostos de 20 ratas adultas da raça Sprague-Dawley com tumores induzidos quimicamente pelo carcinógeno DMBA. As ratas, com 40 a 50 dias de vida, receberam a substância em dose única, por gavagem. Nos grupos TAM e RAL, os animais receberam os SERMs, diariamente, por via oral, 10 dias antes e por mais 80 dias após a indução química com o DMBA. A ação destes SERMs na quimioprevenção de tumores mamários, como também as características morfológicas e histopatológicas dos tumores induzidos, a porcentagem de receptores de estrogênio e a atividade proliferativa da célula tumoral pelo Ki67 foram analisadas. A expressão angiogênica em cada grupo e suas diferenças foram avaliadas com o método qRT-PCR. Após a análise estatística dos resultados observou-se, em relação aos três grupos, que não houve diferenças significantes quanto ao peso, tipo histológico do tumor formado, porcentagem dos receptores de estrogênio e a média do tamanho tumoral. Houve diferenças estatísticas quanto a: 1) número de ratas que desenvolveram tumores (DMBA 100%, tamoxifeno 35% e raloxifeno 15%) ; 2) indução do aparecimento do tumor (DMBA = 32 dias, TAM=46 dias e RAL=57 dias); 3) média, por rata, de tumores formados em cada grupo (DMBA=4,5 tumores, TAM=1,33 tumores e RAL=1,28 tumores); 4) porcentagem de células Ki-67 positivas nos tumores: DMBA 85% dos casos Ki67= 75% a 80%, 15% dos casos Ki67=50%; TAM 43% dos casos Ki57=50% e 57% dos casos Ki67=75% ,e RAL 100% dos casos Ki67=50%; 5) grau histológico tumoral: DMBA 100% grau 3; TAM 71% grau 2 e 29% grau 3 , RAL 100% grau 2; 6) a avaliação da expressão de fatores angiogênicos: nos grupos TAM vs DMBA apresentou maior expressão nos genes Angpt1, Angpt2, Hqf, Hif1a, Itgab3, Lep, Mapk14,Mmp19 predicted, Nrp1, Pgf, Plau, Serpinf1, Tgfb1, Tgfb2, Tek, Timp3, TNF, Vegfa e Vegfc. No grupo RAL vs DMBA, apresentaram maior expressão os genes Hif1a, Itgab3 , Pgf, Plau, Tek e Vegfc. Este grupo mostrou, ainda, menor expressão dos genes Fgf6 e Pecam. Neste modelo experimental, houve maior eficácia do raloxifeno em relação ao tamoxifeno na quimioprevenção mamária; possivelmente, esta maior proteção esteja relacionada com os diferentes fatores angiogênicos expressos nos dois grupos. / Breast cancer is the most common neoplastic disease in the female population, accounting for up to one third of new cancer cases in women in some regions of the world. Prevention, either primary or secondary, is essential for breast cancer control, which depends on identification of the determining factor of the disease, both for initiation and promotion. About 48,930 new cases of breast cancer are detected annually in Brazil, creating a serious Public Health problem. The primary objective of the present study was to determine the action of two SERMs (tamoxifen and raloxifene) as chemopreventive agents and to check the differences between them. The secondary objectives were to evaluate morphological and histological aspects, the percentage of estrogen receptor and proliferative mammary activity (Ki67), and expression of 84 genes involved in modulating the biological process of angiogenesis by qRT-PCR array. Young female Sprague-Dawley rats had chemically-induced tumors by DMBA (7,12Dimethylbenzanthracene) administered by gavage between the ages of 40 to 50 days old. They were divided into three groups: DMBA, TAM and RAL; the two latter groups received SERMs 10 days before DMBA and for 80 days after it. Data analyses showed: 1) the number of rats that developed tumors in each group (DMBA = 20 rats - 100%; TAM = 7 rats - 35%; RAL = 3 rats -15%); 2) induction of tumor onset (DMBA = 32 days, TAM = 46 days, RAL = 57 days); 3) number of tumors formed in each group by individual rat (DMBA = 4.5; TAM = 1.33, and RAL = 1.28); 4) the percentage of Ki67 positive cells in tumors (DMBA = 50 to 80%, TAM = 50 to 75%, and RAL = 50%); 5) histological grade of mammary tumor (DMBA = 100% grade 3, TAM = 71% grade 2 and 29% grade 3, and RAL = 100% grade 2); 6) assessment of expression of angiogenic factors. TAM group compared to DMBA group showed greater expression of the following genes: Angpt2, Hqf, Hif1a, Itgab3, Lep, Mapk14, mmp19 predicted, Nrp1, Pgf, Plau, Serpinf1, Tgfb1, Tgfb2, Tek, Timp3, TNF, Vegfa and Vegfc. RAL group compared to DMBA group showed greater expression of genes Hif1a, Itgab3, Pgf, Plau, Tek and Vegfc; in addition, in this group, genes Fgf6 and Pecam had less expression. In conclusion, in this experimental model, the raloxifene group proved to be more efficient than the tamoxifen group in mammary chemoprevention. The results can be possibly associated with different expressions of angiogenic factors in both groups
480

Avaliação do estresse oxidativo e expressão de genes envolvidos com síntese e oxidação de ácidos graxos em modelo animal de síndrome dos ovários policísticos tratado com metformina e submetida ao exercício físico / Evaluation of oxidative stress and expression of genes involved with fatty acid synthesis and oxidation in animal model of polycystic ovary syndrome treated with metformin and physical exercise

Thiago Hideki Gonçalves 04 December 2017 (has links)
Introdução: A síndrome dos ovários policísticos (SOP) é um distúrbio endócrino complexo com aspectos reprodutivos e metabólicos. Alterações do tecido adiposo participam da fisiopatologia da síndrome e anormalidades do metabolismo de ácidos graxos, bem como o estresse oxidativo, parecem ter papel importante nesse processo. Assim, tanto o exercício físico como a metformina são comumente recomendadas. O objetivo deste estudo foi avaliar a expressão de genes envolvidos com a síntese e oxidação dos ácidos graxos e com os níveis de estresse oxidativo no tecido adiposo de ratas com modelo experimental de SOP tratadas com metformina (Met), submetidas ou não a exercício físico em esteira (Ex). Métodos: Foram utilizadas 46 ratas, Wistar, que receberam no 2º dia de vida, uma única injeção subcutânea de propionato de testosterona (1,25 mg) para a indução de estado de estro permanente e óleo de sésamo (controles). Com 80 dias de idade iniciou-se o experimento e os animais foram divididos em 5 grupos: 1) Controle; 2) SOP ; 3) SOP+Met; 4) SOP+Ex; 5) SOP+Met+Ex.Os tratamentos tiveram duração de 6 semanas. Os animais foram sacrificados aos 120 dias de vida e foram retirados os depósitos das gorduras inguinal e mesentérica. Os depósitos de gordura inguinal e mesentérica foram utilizados para análise da expressão dos genes Acaca, Srebp1, Cpt1 e Cd36, por PCR quantitativo em tempo real, e dos níveis de estresse oxidativo pela dosagem das glutationas reduzida (GSH) e oxidada (GSSG). Adicionalmente, o tamanho dos adipócitos foi analisado por histomorfometria. Resultados: Na análise histomorfométrica dos adipócitos da gordura mesentérica, houve diminuição significativa no grupo SOP+Met+Ex em relação ao grupo SOP. O grupo SOP apresentou hipertrofia em relação ao grupo controle. A análise na gordura inguinal não apresentou nenhuma diferença entre os grupos.Não houve diferença estatística entre os grupos nas análises de expressão gênica das gorduras mesentérica e marrom. Não identificamos diferenças nas medidas de estresse oxidativo (razões GSH/GSSG ,GSH, GSH total, GSSG e razão GSH/GSSG) no tecido adiposo subcutâneo, mesentérico, perigonadal e marrom entre os depósitos de gordura dos animais em nenhum dos grupos avaliados / Introduction: Polycystic ovary syndrome (PCOS) is a complex endocrine disorder, affecting both reproductive and endocrine systems. Changes in adipose tissue are involved in the pathophysiology of the syndrome, and abnormalities of fatty acid metabolism, as well as oxidative stress, appear to play an important role in this process. Thus, both physical exercise and metformin are commonly recommended. The objective of this study was to evaluate the expression of genes involved in the synthesis and oxidation of fatty acids and oxidative stress levels in adipose tissue of in an experimental model of PCOS using Wistar rats. Methods: 46 rats, Wistar, treated with a single subcutaneous injection of testosterone propionate (1.25 mg) for the induction of permanent estrus status (PCOS model) or sesame oil (controls) on the 2nd day of life. Experimental phase of the study was started when animals completed 80 days of age. They were divided into 5 groups: 1) Control; 2) PCOS; 3) PCOS+ Met; 4) PCOS + Ex; 5) PCOS + Met + Ex. Intervention lasted 6 weeks. Animals were sacrificed at 120 days of age and the deposits of inguinal and mesenteric fat were removed. Inguinal and mesenteric fat deposits were used to analyze the expression of Acaca, Srebp1, Cpt1 and Cd36 genes by quantitative realtime PCR and oxidative stress levels by reduced (GSH) and oxidized glutathione (GSSG). In addition, adipocyte size was analyzed by histomorphometry. Results: In the histomorphometric analysis of mesenteric fat adipocytes, there was a significant decrease in the PCOS + Met + Ex group in relation to the PCOS group. PCOS group presented hypertrophy in relation to the control group. Inguinal fat analysis did not present any differences between the groups. There was no statistical difference between groups in analyzes of gene expression of mesenteric and brown fats. We did not identify differences in oxidative stress measurements (GSH / GSSG, GSH, total GSH, GSSG and GSH / GSSG ratio) in the subcutaneous, mesenteric, perigonadal and brown adipose tissue among the fat deposits of the animals in any of the evaluated groups

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