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Proteômica da esquizofrenia: busca por biomarcadores em plaquetas / Proteomic of schizophrenia: research in biomarkers in plateletsJoaquim, Helena Passarelli Giroud 02 February 2018 (has links)
Esquizofrenia é um transtorno psiquiátrico complexo que afeta cerca de 1% da população mundial. Apesar de progressos consideráveis nos últimos anos, a etiologia da doença ainda não foi elucidada principalmente pela heterogeneidade tanto do início quanto da progressão da doença. Frequentemente os sintomas dos pacientes são comuns a outras desordens neuropsiquiátricas, dificultando a diferenciação por meio de métodos essencialmente clínicos. Por isso, pesquisadores têm tentado identificar medidas baseadas em características moleculares que justifiquem e expliquem a etiologia da esquizofrenia. Já há alguns estudos com marcadores no cérebro, mas por esse ser um material com disponibilidade limitada, os esforços tem se concentrado em encontrar biomarcadores periféricos. Este estudo visou traçar um perfil proteico, em plaquetas, de pacientes drug-naïve com diagnóstico de esquizofrenia. Para tanto, comparamos este grupo com controles saudáveis e com controles psiquiátricos. Utilizamos duas abordagens proteômicas complementares para análise: a primeira, uma ferramenta clássica utilizando eletroforese bidimensional com posterior identificação dos spots por espectrometria de massas; e a segunda, uma abordagem de identificação em larga escala por shotgun label-free. Foram analisadas amostras de 16 controles saudáveis, de 11 pacientes com esquizofrenia e de 8 pacientes com transtornos do humor (controle psiquiátrico). Com a eletroforese bidimensional foram identificados 110 spots comuns nos géis de controles saudáveis, 83 spots comuns aos géis de pacientes com esquizofrenia e 80 spots comuns aos géis de pacientes com diagnóstico de transtornos do humor. Foram encontrados 27 spots exclusivos do grupo controle, não sendo detectados em nenhum dos dois grupos de pacientes. Esses spots foram recortados e analisados por espectrometria de massas revelando proteínas relacionadas com: neurotransmissão, sinapse, neurodesenvolvimento, homeostase celular, sinalização de cálcio, apoptose, resposta imune, e estresse oxidativo. Para verificação dos resultados, escolhemos proteínas de acordo com sua função já descrita na literatura e ineditismo na matriz e na casuística estudadas. Por meio da técnica de western blotting, encontramos diminuições significantes nos níveis de anexina A3 e peroxirredoxina 6 nos dois grupos de pacientes. Ambas proteínas diferentemente expressas nos pacientes já foram relacionadas à fosfolipase A2, que é a principal enzima responsável pelo metabolismo de fosfolípides de membrana e tem sido associada à desordens neuropsiquiátricas, inclusive à esquizofrenia. Ainda há algumas abordagens analíticas e bioinformáticas a serem realizadas na busca por candidatos a biomarcadores de esquizofrenia em plaquetas. Os resultados obtidos por shotgun necessitam de uma análise mais aprofundada além da verificação e validação em coortes maiores. A casuística utilizada para este trabalho é bastante valiosa já que permitirá a elucidação de alterações proteômicas já no primeiro episódio psicótico / Schizophrenia is a mulfatorial psychiatric disorder that affects about 1% of the world\'s population. Despite considerable progress in recent years, the etiology of the disease has not yet been elucidated mainly because the heterogeneity of disease onset and progression. Often the symptoms overlap to other neuropsychiatric disorders, which turns difficult to differentiate through essentially clinical methods. The researchers have focused in identify mesureable molecular characteristics that can help to elucidate schizophrenia etiology. There are already important findings regarding markers in the brain, but recent efforts have focused on finding peripheral biomarkers. This study aimed to find a protein profile in platelets of schizophrenia drug-naïve patients. For comparision we recruited two more groups: healthy controls and psychiatric control. We used two complementary proteomic approaches for analysis: a classic tool using two-dimensional electrophoresis with subsequent identification of the spots by mass spectrometry; and a large-scale label-free shotgun identification approach. The sample comprised 11 schizophrenic patients, 8 patients with mood disorders (psychiatric control and 16 healthy controls. 2-DE profiles of each sample were generated in triplicate. 110 proteins spots were identified in most gels of control group, 83 in most gels of schizophrenia group, and 80 proteins spots in most gels of bipolar disorder patients. Among these proteins spots, 76 were common to all three groups; 5 to controls and schizophrenia group; 2 common to controls and bipolar disorders groups; 2 exclusive of bipolar disorder patients and 27 proteins spots were identified exclusively in the control group. The 27 exclusive protein spots of control group were identified by LC-MS/MS. Proteins related to neurotransmission, synapse, neurodevelopment, cellular homeostasis, calcium signaling, apoptosis, immune response, and oxidative stress were identified. To verify the results, we chose proteins according to their function already described in the literature and novelty in platelets and first onset psychosis patients research. By western blotting we verified the difference in levels of annexin A3 and peroxiredoxin 6 between groups, but not of glutathione S-transferase pi 1 or 78-kDa glucose-regulated protein. Both proteins differentially expressed have already been related to phospholipase A2, which is the main enzyme responsible for the membrane phospholipids metabolism and has been associated with neuropsychiatric disorders, including schizophrenia. Despite the good and promising results presented and published, there are still some analytical and bioinformatic approaches to be performed in search for candidates for platelet schizophrenia biomarkers. The data from shotgun approach require further analysis, as well as verification and validation in larger cohorts. The sample enrroled in this study is greatly important and certainly informed us much about the proteomic alterations still in the first onset psychosis
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Investigation of the effect of inorganic nitrate on platelet and endothelial function in healthy individuals and in patients with hypercholesterolaemiaVelmurugan, Shanti January 2014 (has links)
Ingestion of vegetables rich in inorganic nitrate (NO3-) content has emerged as an effective method, via the formation of a nitrite (NO2-) intermediate, for acutely elevating vascular nitric oxide (NO) levels. As such a number of beneficial effects of NO3- ingestion have been demonstrated including the suggestion that platelet reactivity is reduced. I initially investigated whether inorganic NO3- supplementation might also reduce platelet reactivity in healthy volunteers and have determined the mechanisms involved in the effects seen. I conducted a randomised crossover study in 24 (12 of each sex) healthy subjects assessing the acute effects of potassium nitrate capsules (KNO3, 8 mmol) vs placebo (KCl) control capsule ingestion on platelet reactivity. Inorganic NO3- ingested via supplementation raised circulating NO3- and NO2- levels in both sexes and attenuated ex vivo platelet aggregation responses to adenosine diphosphate (ADP) and, albeit to a lesser extent, collagen but not epinephrine in male but not female volunteers. These inhibitory effects were associated with a reduced platelet P-selectin expression and elevated platelet cyclic guanosine monophosphate (cGMP) levels. In addition, I have shown that NO2- reduction to NO occurs at the level of the erythrocyte and not the platelet. These results demonstrate that inorganic NO3- ingestion, whether via the diet or through supplementation, results in a modest decrease in platelet reactivity in healthy males. I then sought to examine the effects of 6 weeks daily intake of NO3--rich beetroot juice versus a placebo NO3--deplete juice on endothelial and platelet function in a cohort of otherwise healthy non-diabetic untreated hypercholesterolaemics. In this randomised double blind placebo controlled parallel study 69 subjects were recruited. The primary end point was change in endothelial function determined using ultrasound flow-mediated dilatation (FMD). Secondary endpoints included change in pulse wave analysis (PWA), aortic pulse wave velocity (aPWV), platelet P-selectin and platelet monocyte aggregate (PMA) expression and plasma, urine and salivary NO3- and NO2- levels. Baseline characteristics, including lipid levels, were similar between the groups. Dietary NO3- caused an improvement in FMD of ~24% from 4.6%±2.2% to 5.7%±2.6% in the treatment group (p<0.001) not seen in the placebo group (4.5%±1.9% versus 4.3%±1.8% p=0.07). This improvement in FMD was also noted following acute administration of dietary NO3-. Small but significant improvements also occurred in aPWV and PWA augmentation index (p=0.04). The % of platelet monocyte aggregates was significantly reduced in the NO3- limb by 7.6% versus an increase of 10.1% in the placebo group (p=0.004). No adverse effects of dietary NO3- were detected. In this study population, chronic dietary NO3- ingestion improves endothelial function, vascular stiffness and platelet markers of atherogenesis in a cohort of hypercholesterolaemics who are otherwise at increased risk of cardiovascular disease (CVD). This thesis provides strong support for assessment of the potential of dietary NO3- as a primary prevention strategy to prevent atherothrombotic and atherogenic complications in larger cohorts.
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Design and Optimization of Recombinant Antibodies Directed Against Platelet Glycoprotein VI with Therapeutic and Diagnostic Potentials / Conception et optimisation d'anticorps recombinants à potentiel thérapeutique et diagnostique, dirigés contre la Glycoprotéine VI (GPVI) plaquettaireZahid, Muhammad 24 November 2011 (has links)
La glycoprotéine VI (GP VI) des plaquettes sanguines humaines est le récepteur principal du collagène, composé le plus thrombogénique d'une paroi vasculaire lésée. Ainsi, GPVI est souvent considérée comme une cible de premier plan pour développer des tests diagnostiques ou des stratégies thérapeutiques innovantes, efficaces et sûres afin d'améliorer encore la prise en charge des accidents ischémiques. Les anticorps monoclonaux et leurs fragments actifs produits par ingénierie moléculaire constituent aujourd'hui une nouvelle classe de biomolécules en plein essor avec des propriétés bien adaptées à des applications thérapeutiques et diagnostiques. Notre groupe a produit plusieurs anticorps monoclonaux anti-GPVI par immunisation génique de souris. Ces anticorps ont une affinité élevé pour leur cible. Ils de distinguent les uns des autres par leur spécificité épitopique ainsi que par les effets engendrés par leur liaison à GPVI. Parmi ces anticorps, l'un présente un fort potentiel diagnostique parce qu'il reconnait les formes mono- et dimériques de GPVI, mais sa liaison aux plaquettes peut induire une activation ou la perte de GPVI. Un autre anticorps présente un fort potentiel thérapeutique parce que ses fragments actifs monovalents obtenus par papaïnolyse neutralisent l'interaction entre les plaquettes et le collagène, sans activer les plaquette. Cependant, l'origine xénogénique de cet anticorps est responsable d'une forte immunogénicité qui en interdit des applications en médecine humaine. Dans cette étude, nous avons conçus un fragments variable d'anticorps simple chaine (scFv) utile pour quantifier l'expression de la GPVI à la surface des plaquettes sanguines. Ce scFv a été reformaté de façon à lui insérer un motif de reconnaissance de la Protéine L (PpL) qui facilite sa détection et sa purification sans avoir recours à un peptide "drapeau". Nous avons également humanisé et créé plusieurs fragments d'anticorps recombinants monovalents inhibiteurs de l'interaction GPVI / collagène. Ces fragments d'anticorps présentent un potentiel thérapeutique élevé. / Human platelets glycoprotein VI (GPVI) is evidenced to be a platelet receptor of major importance in the occurrence of arterial thrombosis. Thus, it can be considered to be of great interest in diagnosis and therapeutic of atheriosclerotic diseases. Antibodies are powerful molecules which can be used in both diagnostic as well as for therapeutic purposes due to their unique characteristics. Monoclonal and recombinant antibodies have antigen restricted specificity, high affinity and can be used in various assays. Moreover, the good knowledge of their structure and molecular engineering facilities now allows the antibody modulation according to desired properties.Our group has already produced several monoclonal antibodies to human GPVI by gene gun immunization against the immunoadhesin hGPVI-Fc, which differ in fine epitopespecificity, affinity and other functional properties (Lecut et al. 2003). One, 3J24, with diagnostic potential while the other, 9O12, has a therapeutic potential because it blocks the binding of GPVI to collagen. Its Fab fragment has been extensively characterized in vitro,ex vivo and in vivo for its antithrombotic properties.Here, we designed and reshaped a single-chain antibody fragment (scFv) based on 3J24variable domains for the quantification of GPVI with diagnostic potential. We were also involved in the design, production and functional evaluation of humanized anti-GPVI recombinant antibody fragments (scFvs and Fabs) with therapeutic properties.
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Détermination des prédicteurs de sévérité des effets indésirables receveurs au cours des transfusions de concentrés plaquettaires / Determination of severity predictors of adverse reactions during platelet transfusionsSut, Caroline 19 December 2017 (has links)
La transfusion sanguine est une thérapeutique indispensable pour laquelle il n’existe pas actuellement de substitut. La transfusion de produits sanguins labiles est dans la grande majorité des cas très bien tolérée mais elle peut être à l’origine d’effets indésirables chez les receveurs (EIR) notamment de type inflammatoire. Ceci dépend de facteurs liés aux produits eux-mêmes et/ou aux receveurs de par leur prédisposition génétique et de leur état clinique. Les concentrés plaquettaires (CP) sont la principale source de manifestations inflammatoires et/ou allergiques. Ceci est notamment dû, en partie, à la capacité des plaquettes à sécréter une multitude de molécules ayant une activité inflammatoire. De plus, les processus de collecte, de préparation et de conservation induisent un stress vis-à-vis des cellules, qui peut activer les plaquettes et donc induire la production de produits inflammatoires dans les CP. Le but de ce travail de thèse a été dans un premier temps d’identifier les molécules les plus impliquées dans les manifestations inflammatoires. Le sCD40L en particulier est identifié comme étant largement impliqué dans les EIR après transfusion de CP, mais pas systématiquement. Aussi, la composante inflammatoire de ces réactions est multifactorielle. De plus, nous avons évalué le potentiel inflammatoire des CP sur l’endothélium vasculaire. Des différences d’activation des cellules endothéliales, dans un modèle in vitro, ont été observées lorsqu’elles sont en présence de surnageants de CP ayant induits un EIR. Ce travail de thèse poursuit l’effort entrepris par notre équipe de recherche, en vue de prédire la survenue d’EIR et de préciser les mécanismes qui influencent la physiopathologie plaquettaire transfusionnelle ; un corollaire de ces travaux est ainsi d’optimiser les processus de production et de conditionnement des CP transfusés afin de réduire ces réactions inflammatoires. / Blood transfusion is an indispensable therapy for which there is currently no substitute. Transfusion of blood products is in the great majority of cases very well tolerated but it can be at the origin of serious adverse reactions (SARs), notably of inflammatory reactions. This depends on the factors related to the products themselves and/or to the recipients, their genetic predisposition and clinical condition. Platelet concentrates (PCs) are the main source of inflammatory and/or allergic manifestations. This is due, in part, to the ability of platelets to secrete a multitude of molecules with inflammatory activity. In addition, the collection, processing and storage conditions induce stress on cells, which can activate platelets and thus induce the production of inflammatory products in PCs. The purpose of this work is to identify the molecules involved in inflammatory manifestations. sCD40L was identified as being involved in SARs after PCs transfusion, but not systematically. Also, the inflammatory component of these reactions is multifactorial. In addition, we evaluated the inflammatory potential of PCs on the vascular endothelium. Differences in endothelial cell activation, in an in vitro model, were observed when they were in the presence of PC supernatants involved in SARs. This thesis work continues the effort undertaken by our research team to predict the occurrence of SARs and to clarify the mechanisms that influence transfusional platelet physiopathology; a corollary of this work is to optimize the production and conditioning process of PCs transfused in order to reduce these inflammatory reactions.
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Cross-flow filtration, transmission electron micrographic analysis and blood compatibility testing of collagen composite materials for use as vascular prosthesesForbes, Martin J January 1980 (has links)
Thesis (Mech.E)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 355-373. / by Martin J. Forbes. / Mech.E
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Envolvimento da resposta imune humoral no desenvolvimento da anemia e das alterações quantitativas e qualitativas das plaquetas na erliquiose canina experimental / Involvement of humoral immune response on development of anemia and quantitative and qualitative platelets disorders in experimental canine ehrlichiosisBrandão, Leonardo Pinto 29 July 2005 (has links)
Com o objetivo de avaliar o envolvimento da resposta imune humoral no desenvolvimento da anemia e das alterações quantitativas e qualitativas das plaquetas na erliquiose canina, sete cães adultos, livres de infecção, foram inoculados com E. canis e acompanhados durante 10 semanas. Três cães permaneceram como controles. Os animais foram submetidos a exame físico diário e avaliação laboratorial (hemograma, contagem de plaquetas, mielograma, bioquímica sangüínea, fragilidade osmótica eritrocitária e teste de Coombs), reação em cadeia da polimerase (PCR), pesquisa de anticorpos anti-E. canis, antiplaquetários e antimegacariocíticos (IFI), e teste da atividade de agregação plaquetária, em diferentes momentos durante o período de observação. Febre, esplenomegalia, linfadenomegalia, trombocitopenia, anemia não regenerativa, aumento das atividades séricas da ALT, AST e FA foram as principais alterações clínicas e de patologia clínica observadas, com pico máximo entre o 21º e 28º dias pós-infecção. Houve diminuição da capacidade de agregação plaquetária dos animais infectados (p<0,05) nos dias 14, 21, 28 e 35 pós-infecção e aumento do número das células megacariocíticas, principalmente seus precursores (megacarioblastos e pró-megacariócitos) no 14º dia pós-infecção. Não foram detectados anticorpos antiplaquetários ou antimegacariocíticos. O teste de Coombs, bem como a fragilidade osmótica eritrocitária, mantiveram-se inalterados, comprovando não ter ocorrido hemólise imunomediada. Conclui-se que a anemia desenvolvida durante a fase aguda da infecção experimental por E. canis, de característica eritroregenerativa, ainda que tardia, pelo menos nos animais estudados, não teve envolvimento de mecanismo imunológico direcionado contra as hemácias, e ainda, que a causa da trombocitopenia e da hipofunção plaquetária observada durante esta fase da doença não parece estar relacionada ao desenvolvimento de mecanismos imunológicos direcionados contra as plaquetas ou seus precursores. / In order to determine the involvement of humoral and immune response on development of anemia and quantitative and qualitative platelets disorders in experimental canine ehrlichiosis, seven adult naïve dogs were inoculated with E. canis and followed during 10 weeks. Three dogs were remained as control. Daily clinical evaluation and laboratorial exams (hematological, platelet counts, bone marrow evaluation, biochemistry, erythrocyte osmotic fragility and Coombs? test) polymerase chain reaction assay (PCR), anti-E.canis, antiplatelet and antimegakaryocyte antibodies detection (IFA) and platelet aggregation studies were evaluated at different moments during all the experimental period. Fever, splenomegaly, lymphadenomegaly, thrombocytopenia, non-regenerative anemia and increase on liver?s enzymes serum activity (ALT, AST and ALP) were the main clinical and laboratorial findings observed, with the highest point between days 21 and 28 post-infection. The infected animals showed a decrease in platelet aggregation responses (p<0.05) on days 14, 21, 28 and 35 post-infection and increase of megakaryocytic cells, mainly its precursors (megakaryoblasts and promegakaryocytes) on day 14 post-infection. It weren?t detected any antiplatelet or antimegakaryocyte antibodies, as well as, there were no variations on erythrocyte osmotic fragility and Coombs? tests results, which confirms the absence of immune-mediated hemolysis. It is concluded that the anemia observed during the experimental acute phase of the E. canis infection, with regenerative pattern, even though late, at least in the studied animals, wasn?t related with immune mechanism against the red blood cells, and that, the thrombocytopenia and platelet dysfunction observed during this phase of the disease don?t seen to be related with immune mechanisms against platelets or its precursors.
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Plasma homocysteine, atheromatous vascular disease and platelet function. / CUHK electronic theses & dissertations collection / Digital dissertation consortiumJanuary 2002 (has links)
Fan Boli. / "January 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 219-248). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
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Influência da associação do plasma rico em plaquetas ao enxerto de osso autógeno no reparo ósseo de defeitos de tamanho crítico em calvárias de coelhos : estudo histológico e histométrico /Melo, Luiz Gustavo Nascimento de. January 2007 (has links)
Orientador: Maria José Hitomi Nagata / Banca: Mário Taba Junior / Banca: Álvaro Francisco Bosco / Banca: Ronaldo Célio Mariano / Banca: Valdir Gouveia Garcia / Resumo: O objetivo do presente trabalho foi avaliar, histologicamente, a influência da associação do plasma rico em plaquetas (PRP) ao enxerto de osso autógeno (OA) no reparo ósseo de defeitos de tamanho crítico (DTC) em calvárias de coelhos. Sessenta coelhos foram divididos em 3 grupos: C (controle), OA (osso autógeno) e OA/PRP (osso autógeno associado ao plasma rico em plaquetas). Um defeito de tamanho crítico, com 15 mm de diâmetro, foi criado na calvária de cada animal. No Grupo C, o defeito foi preenchido somente com coágulo sanguíneo. No Grupo OA, o defeito foi preenchido com osso autógeno particulado. No Grupo OA/PRP, o defeito foi preenchido com osso autógeno particulado associado ao PRP. Todos os grupos foram divididos em subgrupos (n = 10) para eutanásia aos 30 ou 90 dias pós-operatórios. Foram realizadas análises histológica e histométrica. A quantidade de osso neoformado foi calculada como uma porcentagem da área total do defeito original. Os dados em porcentagem foram transformados em raiz quadrada para análise estatística (ANOVA, teste t, p<0,05). Aos 30 dias pós-operatórios, o Grupo OA/PRP apresentou uma quantidade significativamente maior de osso neoformado que o Grupo OA (64,44% e 46,88%, respectivamente). Aos 90 dias, todos os espécimes dos Grupos OA/PRP e OA mostraram fechamento ósseo completo do defeito, com quantidades similares de osso neoformado (77,9% e 75%, respectivamente). Dentro dos limites deste trabalho, pode-se concluir que o PRP acelerou o processo de reparo do enxerto de osso autógeno em defeitos de tamanho crítico em calvária de coelhos. / Abstract: The purpose of this study was to histologically analyze the effect of platelet-rich plasma (PRP) on bone healing in an autogenous bone graft placed in surgically created criticalsize defects (CSD) in rabbit calvaria. 60 rabbits were divided into 3 groups: C (control); AB (autogenous bone graft) and AB/PRP (autogenous bone graft with platelet-rich plasma). A 15 mm diameter CSD was created in the calvarium of each animal. In Group C the defect was filled by blood clot only. In Group AB the defect was filled with particulate autogenous bone. In Group PRP it was filled with particulate autogenous bone in combination with platelet-rich plasma. All groups were divided into subgroups (n=10) and euthanized at either 30 or 90 days post-operative. Histometric, using image analysis software, and histologic analyses were performed. Amount of new bone was calculated as a percentage of the total area of the original defect. Percentage data were transformed into square root for statistical analysis (ANOVA, t test, p<0.05). At 30 days post-op, Group AB/PRP had a statistically greater amount of bone formation than Group AB (64.44% and 46.88%, respectively). At 90 days, complete bone regeneration of the defect was seen in all specimens of Groups AB/PRP and AB, with similar amounts of newly formed bone (77.9% and 75%, respectively). Within the limits of this study, it can be concluded that PRP accelerated the healing of autogenous bone graft in critical-size defects in rabbit calvaria. / Doutor
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Novel insights into megakaryopoiesis, thrombopoiesis and acute coronary thrombosis : transcriptome profiling of the haematopoietic stem cell, megakaryocyte and plateletChoudry, Fizzah Aziz January 2018 (has links)
The aim of this project was to investigate the transcriptome of human haematopoietic stem cells (HSCs), megakaryocytes and platelets to gain insights into steady state and accelerated thrombopoiesis that occurs in states of haemostatic demand and in thrombosis by applying these findings to the pathological setting of acute coronary thrombosis. To investigate transcriptional heterogeneity within the human HSC population, single cell RNA sequencing was performed in human bone marrow HSCs. Transcriptionally distinct subpopulations were identified including two megakaryocyte biased subsets with potentially differing functional relevance. Both populations expressed megakaryocyte specific transcripts, one of which also co-expressed common myeloid and megakaryocyte-erythroid progenitor transcripts while the other did not. This study represents the first interrogation of the human bone marrow megakaryocyte transcriptome. Cells were collected from healthy human bone marrow and analysed by low input and single cell RNA sequencing. To identify novel drivers of megakaryocyte maturation, the human bone marrow megakaryocyte transcriptome was compared to that of megakaryocytes cultured from human CD34+ cells, a process known to generate immature megakaryocytes. Transcriptional signatures associated with increasing megakaryocyte ploidy were then investigated. Increasing megakaryocyte ploidy level was found to be associated with an upregulation of transcripts involved in translation and protein processing as well as expression of a number of transmembrane receptors which might have functional relevance. Finally, the pathological setting of acute coronary thrombosis was used as a model for accelerated thrombopoiesis. Megakaryocyte and platelet transcriptomes were compared between patients with acute myocardial infarction (AMI) as well as severe coronary disease and a control group. The transcriptional signature relating to disease compared to control in megakaryocytes included upregulation of platelet activation related transcripts in megakaryocytes isolated from patients with AMI and severe coronary artery disease.
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Uso contínuo de antipsicóticos modula fosfolipase A2 e glicogênico sintase quinase-3 beta em plaquetas de pacientes com esquizofrenia / Antipsychotics prolonged use modulates phospholipase A2 and glycogen synthase kinase-3 beta in platelets from patients with schizophreniaFerreira, Aline Siqueira 09 March 2012 (has links)
Duas enzimas têm-se destacado como possíveis marcadores biológicos periféricos na esquizofrenia: a fosfolipase A2 (PLA2) e a glicogênio sintase quinase-3 beta (GSK-3B). Essas moléculas exercem importante influência na arquitetura e plasticidade celulares, na regulação de vias metabólicas comuns (metabolismo de fosfolípides e via Wnt), em fatores de transcrição, na regulação de genes e na sobrevivência celular. Tais aspectos tornam pertinentes as investigações a respeito da possível participação dessas enzimas na fisiopatologia da esquizofrenia. Foi verificada a atividade de subtipos de PLA2 (método radioenzimático: iPLA2, cPLA2 e sPLA2) e os níveis de GSK-3B total (GSK-3Bt) e fosforilada [p(Ser9)-GSK-3B] (ELISA) em plaquetas de pacientes com esquizofrenia inicialmente livres de tratamento medicamentoso com média de 5 anos de doença (D+5a) (n=10), aos quais foi prescrita a olanzapina. Foi avaliado também um grupo de pacientes livres de tratamento medicamentoso com menos de 6 meses de sintomas psicóticos (D-6m) (n=6) aos quais foi posteriormente prescrito o haloperidol. Esses pacientes foram comparados com um grupo controle (n = 20) e avaliados longitudinalmente após o tratamento descrito por 8 semanas. Um grupo de 40 pacientes com esquizofrenia (tempo médio da doença: 17 anos) com pelo menos 6 meses de tratamento com antipsicótico (clozapina, olanzapina ou haloperidol) foi ainda avaliado. Os sintomas clínicos foram avaliados por meio da Escala de Avaliação das Síndromes Positiva e Negativa (PANSS). Quando comparado com o grupo controle, os pacientes D+5a apresentaram aumento da atividade de iPLA2 (p<0,01) e os pacientes D-6m apresentaram aumento da atividade de sPLA2 (p<0,05). Na avaliação longitudinal, somente a olanzapina diminuiu a atividade de iPLA2, cPLA2 e sPLA2 (p<0,01). Quando comparada a atividade dos subtipos de PLA2 entre os pacientes medicados a pelo menos 6 meses e o grupo controle, não foram observadas diferenças significativas. Quando comparado com o grupo controle, os pacientes D+5a apresentaram diminuição dos níveis de GSK-3Bt e p(Ser9)-GSK-3B (p<0,05). Na avaliação longitudinal, foi observado que somente a olanzapina aumentou os níveis de GSK-3Bt e p(Ser9)-GSK-3B (p < 0,01). Quando comparados os níveis de GSK-3Bt e p(Ser9)-GSK-3B entre os pacientes medicados a pelo menos 6 meses e o grupo controle não foram observadas diferenças significativas. Para os pacientes medicados a pelo menos 6 meses foram observadas correlações entre a sub-escala negativa da PANSS e os níveis de p(Ser9)-GSK-3B (r=,53, p<0,001). Sugere-se que a medicação module PLA2 e GSK-3B, independente do antipsicótico utilizado. Esses resultados apontam para uma futura aplicação dessas enzimas na verificação de adesão ao tratamento e estabilização do quadro clínico / The enzymes phospholipases A2 (PLA2) and glycogen synthase kinase-3 beta (GSK-3B) are thought to play a role in schizophrenia by influencing cellular architecture and plasticity, common signaling pathways (phospholipids metabolism and Wnt pathway), gene transcription, regulation factors and apoptosis. These aspects motivated the investigation of both these enzymes in schizophrenia. The activities of PLA2 subtypes (iPLA2, cPLA2 and sPLA2 by radio enzymatic method) and the levels of total GSK-3B and phosphorylated GSK-3B [p(Ser9)-GSK-3B] (by immune enzyme assay) were performed in platelets of drug free patients with schizophrenia for average 5 years of disease (D+5y) (n=10), who was lately prescribed with olanzapine and in drug naïve patients with less than 6 months of psychotic symptoms (D-6m) who was lately prescribed with haloperidol. These patients were compared to a control group (n=20) and were longitudinally evaluated after 8 weeks of monotherapy treatment with the prescribed antipsychotic. These enzymes were also investigated in a group of 40 patients with schizophrenia (mean duration of disease: 17 years) who were at least 6 months treated with antipsychotic (clozapine; olanzapine or haloperidol). Psychopathology was assessed with the Positive and Negative Syndrome Scale (PANSS). Patients D+5y presented higher iPLA2 activity than control group (p < 0.01) and patients D-6m presented higher sPLA2 activity than control group (p < 0.05). On longitudinal evaluation, only olanzapine decreased iPLA2, cPLA2 and sPLA2 activities (p < 0.01). In the long-term medicated patients group compared to the control group, no differences regarding PLA2 subtype activity were found. Patients D+5y presented lower GSK-3Bt and p(Ser9)-GSK-3B levels than control group (p<0.05). On longitudinal evaluation, only olanzapine increased GSK-3Bt and p(Ser9)-GSK-3B levels (p < 0.01). In the long-term medicated patients group compared to the control group, no differences regarding GSK-3B levels were found. For long-term medicated patients, it was observed correlation between p(Ser9)-GSK-3B and the PANSS negative syndrome subscale score (r = .53, p < 0.001). It was suggested that antipsychotic treatment modulated PLA2 and GSK-3B, in spite of the drug used. The results pointed to a future use of these enzymes to verify drug treatment compliance and clinical stabilization
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