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Efeito do extrato de aroeira no processo de proliferação e mineralização de osteoblastos in vitro / Effect of aroira extract in the process of proliferation and mineralization of osteoblasts in vitroMatos, Adriana Arruda 30 August 2013 (has links)
Em virtude do uso indiscriminado de antimicrobianos, a resistência de microrganismos patogênicos à diversas drogas tem aumentado nos últimos anos. Essa situação tem forçado pesquisadores a procurarem por novas drogas, tais como os medicamentos fitoterápicos que são preparações farmacêuticas (extratos, tinturas, pomadas e cápsulas) de ervas medicinais, utilizadas para o tratamento de inúmeras doenças. Uma das espécies brasileiras do cerrado que tem despertado o interesse de várias áreas é a aroeira (Myracrodruon urundeuva), por apresentar ação antiinflamatória, antiproliferativa, antioxidante e antimicrobiana. Dessa maneira o objetivo deste trabalho foi de avaliar o efeito do extrato hidroalcoólico de aroeira na viabilidade celular dos osteoblastos humanos e analisar a influência do extrato hidroalcoólico de aroeira na expressão de metaloproteinase de matriz 2 (MMP-2) e anquilose progressiva humana (ANKH). Nesse estudo foram utilizados osteoblastos humanos cultivados em Meio de Eagle modificado por Dulbecco (DMEM) adicionado de 10% de soro fetal bovino (SFB). Após atingirem a subconfluência as células foram plaqueadas e tratadas com diferentes concentrações do extrato hidroalcoólico de aroeira (Extrato Bruto; 1:10; 1:100; 1:1.000; 1:10.000). Após 24, 48, 72, 96 horas foi realizada a análise da viabilidade celular por meio da redução do MTT (brometo de 3-(4,5-dimetiltiazol-2-yl)-2,5- difeniltetrazólio), captação do vermelho neutro e cristal violeta. Também foi feita a redução do MTT após 7, 14, 21 e 28 dias de tratamento com o extrato, para verificar se as células permaneciam viáveis nesses períodos. A análise da expressão gênica de MMP-2 e ANKH foi realizada pelo RT-PCR em tempo real nos períodos de 24, 48, 72 horas, 7, 14, 21 e 28 dias. Os ensaio de viabilidade celular (redução do MTT, captação do vermelho e cristal violeta) mostraram que houve o aumento da viabilidade celular nos grupos tratados com o extrato a 1:10.000; e a diminuição da viabilidade dos osteoblastos humanos nos grupos com extrato bruto e com 1:10. Com relação à expressão de MMP-2 e ANKH, os resultados mostraram que o extrato promoveu uma modulação da expressão desses genes no decorrer dos períodos em comparação com o grupo controle. De um modo geral o extrato, em maiores concentrações (1:100), inibiu a expressão de MMP-2 e aumentou a expressão de ANKH. Tendo em vista os resultados obtidos concluímos que o extrato hidroalcoólico de aroeira em altas concentrações promove redução e/ou morte celular dos osteoblastos humanos e ainda modulam a expressão de MMP-2 e ANKH. / Due to the indiscriminate use of antimicrobial, the resistance of pathogenic microorganisms to various drugs has increased in recent years. This situation has forced researchers to search for new drugs, such as herbal medicines that are pharmaceutical preparations (extracts, tinctures, ointments and capsules) medicinal herb, used for the treatment of numerous diseases. One species of the Brazil that has aroused interest in many areas is the aroeira (Myracrodruon urundeuva) because of its anti-inflammatory, antiproliferative, antioxidant and antimicrobial. Thus the aim of this work was to evaluate the effect of hydroalcoholic extract of aroeira on cell viability of human osteoblasts and to analyze extract on the expression of matrix metalloproteinase 2 (MMP-2) and human progressive ankylosis (ANKH) . In this study, we used human osteoblasts cultured in Eagle\'s medium modified by Dulbecco (DMEM) supplemented with 10% fetal bovine serum (FBS). After reaching subconfluence cells were plated and treated with different concentrations of the aroeira extract hydroalcoholic (brute extract , 1:10, 1:100, 1:1.000, 1:10:000). After 24, 48, 72 and 96 hours analysis was performed of cell viability by the reduction of MTT (3 - (4,5-dimethylthiazol-2-yl) -2,5 - diphenyltetrazolium bromide) uptake of neutral red and crystal violet. It was also made MTT reduction after 7, 14, 21 and 28 days of treatment with the extract, to check if the cells remained viable during these periods. The analysis of the gene expression of MMP-2 and ANKH was performed by Real Time RT-PCR in periods of 24, 48 hours, 72 hours, 7, 14, 21 and 28 days. The cell viability assay (MTT reduction, uptake of neutral red and crystal violet) showed that there was a tendency of increased cell viability in the groups treated with the extract 1:10.000, and decreased viability of human osteoblast cells in groups with brute extract and 1:10. With respect to expression of MMP-2 and ANKH, the results showed that the extract promoted a modulation of expression of these genes during the periods, compared to the control group. Generally extract at higher concentrations (1:100) both inhibited the expression of MMP-2 and increased rhe expression of ANKH. Given the results we conclude that the hydroalcoholic extract of aroeira in high concentrations causes a reduction and / or cell death of human osteoblasts and also modulate the expressio of MMP-2 and ANKH.
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Papel do fator de transcrição AP-1 na hipernocicepção neuropática em camundongos / Role of the AP-1 transcription factor in neuropathic hypernociception in mice.Poloni, Rafael 24 February 2014 (has links)
A dor neuropática pode ser causada por lesões e/ou disfunções no sistema somatossensorial. Nestes tipos de dores, alterações plásticas ao longo de todo o sistema sensorial nociceptivo estão associadas à cronificação do processo doloroso. A plasticidade observada pode ser resultante da indução e/ou repressão de genes, os quais geralmente são modulados por fatores de transcrição. Um dos principais fatores de transcrição até então conhecido é a proteína ativadora-1 (AP-1), que pode ser estruturalmente formado principalmente por proteínas das famílias Jun e Fos. Entretanto, na dor neuropática, a participação e o papel do AP-1 não estão bem elucidados. Dessa forma, a hipótese deste trabalho é que a ativação do AP-1 contribua para a indução e/ou manutenção da dor neuropática, através da ativação de células gliais e de proteinocinases ativadas por mitógenos (MAPK) e por indução da produção e liberação de mediadores pró-inflamatórios, bem como de metaloproteinases da matriz extracelular (MMP) na medula espinal. Esses fatores contribuem para sensibilização central causada pela SNI, facilitando a transmissão dolorosa. Assim, a inibição do AP-1 seria uma potencial estratégia terapêutica no tratamento da dor neuropática. Foi utilizado o modelo experimental de dor neuropática de lesão limitada do nervo isquiático (SNI, Spared Nerve Injury) em camundongos, os quais receberam injeção intratecal (i.t.) do inibidor de AP-1, SR11302, ou seu veículo (DMSO, tween® 20 e salina). O tratamento com o inibidor de AP-1 reduziu a hipernocicepção mecânica causada pela SNI, e o perfil de redução sugeriu que esse fator de transcrição esteja relacionado com a manutenção da dor neuropática. No sétimo dia após a SNI, observou-se na medula espinal dos camundongos, ativação da microglia, dos astrócitos e das MAPK, além de aumento na expressão de TNF-, interleucina (IL)-6, IL-1, IL-17A, quimiocina derivada de queratinócito (KC), proteína quimiotáxica de monócitos (MCP-1), óxido nítrico (NO), NO sintase induzível e das MMP-2 e -9. Todos esses eventos estão associados à sensibilização central, portanto, contribuem para a facilitação da transmissão nociceptiva. O tratamento com o inibidor de AP-1 SR11302 impediu, pelo menos parcialmente, a ativação das células gliais e das MAPK e bloqueou o aumento na expressão de todos esses mediadores pró-inflamatórios e das MMPs na medula espinal. Assim, o fator de transcrição AP-1 e, consequentemente, suas vias a jusante (downstream) são potenciais alvos farmacológicos no tratamento da dor neuropática. / Neuropathic pain results from nerve damage or dysfunction, which is associated to the painful process of chronification. This process may include participation of the inducible genes, which may be modulated by transcription factors, including the activator protein-1 (AP-1), which can structurally be formed by proteins from Jun and Fos families. However, the participation and the role of AP-1 neuropathic pain remain unclear. Our hypothesis is that the activation of AP-1 would contribute for the induction and/or maintenance of neuropathic pain, by inducing the glial cells activation and mitogen-activated protein kinases, and by inducing the production/release of pro-inflammatory mediators and extracellular matrix metalloproteinase (MMP) in mices spinal cord. All these factors are contributing to SNI-evoked central sensitization, facilitating pain transmission. Thus, inhibition of AP-1 would be a potential drug target in the treatment of neuropathic pain. The animals received inhalatory anesthesia (2% isoflurane) and were submitted to an experimental model of neuropathic pain Spared Nerve Injury (SNI). The animals were treated intrathecally (i.t.) with AP-1 inhibitor SR11302 or vehicle (DMSO, tween®20 and saline). Treatment with AP-1 inhibitor reduced the SNI-induced mechanical hypernociception, suggesting that this transcription factor is related to the maintenance of neuropathic pain. On the seventh day after SNI, there was in the spinal cord of mice microglia, astrocytes and MAPK activation, increased of expression of TNF-, interleukin (IL)-6, IL-1, IL-17A, keratinocyte-derived chemokine (KC), monocyte chemoattractant protein-1 (MCP-1), nitric oxide (NO) and inducible NO synthase, and increased the expression of MMP-2 and -9. All of these effects are related with central sensitization, thus facilitating nociceptive transmission. However, treatment with SR11302 prevented, at least partially, activation of MAPK and glial cells, as well as prevented the increase in expression of all these pro-inflammatory mediators and MMPs in the spinal cord. Thus, inhibition of AP-1 and hence its way downstream is a potential pharmacological target in the treatment of neuropathic pain.
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"Efeito da terapia com laser em baixa intensidade (LILT) na produção de proteínas por macrófagos estimulados por cimentos endodônticos" / Effect of low level laser therapy (LILT) on the protein secretion by endodontic sealers stimulated macrophagesSousa, Lorena Ribeiro de 08 March 2006 (has links)
A terapia endodôntica visa o selamento biológico do complexo sistema apical, contribuindo para isso, as substâncias usadas no tratamento e a resposta imune do paciente. A LILT tem mostrado atividade antiinflamatória, favorecendo o processo reparacional. Sendo assim, este trabalho objetivou analisar o efeito da LILT na atividade secretória de macrófagos, previamente ativados por IFN-? e LPS de E.coli, e estimulados por substâncias liberadas de três tipos de cimentos endodônticos, um a base de óxido de zinco e eugenol, outro a base de hidróxido de cálcio e um terceiro resinoso. A citotoxicidade dessas substâncias foi avaliada usando a técnica de análise do MTT. Macrófagos ativados foram estimulados por essas substâncias ou não (controle) e então, irradiados ou não (controle) e a secreção de proteínas próinflamatórias (interleucina-1 b, fator de necrose tumoral-a e metaloproteinase da matriz-1) foram analisadas pelo teste ELISA. As irradiações foram realizadas com um laser GaAlAs (780 nm, 70 mW, ponta da fibra de 4 mm2, 1.67 seg, 3 J/cm2). Foram usadas duas aplicações de irradiação com intervalo de 6 h. Os dados obtidos foram tratados por Análise de Variância, quando de distribuição normal, ou teste de Friedman, quando de distribuição não normal, com nível de significância de 5 % (p = 0,05). A viabilidade dos controles e células tratados pelos cimentos endodônticos foi similar. Produção de IL-1 b e TNF-a foram observadas. Houve alta produção de MMP-1. Entretanto, sem diferenças estatísticas entre os grupos experimentais. Os grupos irradiados apresentaram resultados similares aos não irradiados. Substâncias liberadas pelos cimentos endodônticos testados não se mostraram citotóxicas nas condições deste experimento. Essas substâncias, bem como a LILT, no parâmetro utilizado, não causam alteração na atividade de secreção de MMP-1, IL-1 b e TNF-a por macrófagos ativados. / The endodontic therapy seeks the dental root canal biological sealing, depending on substances used in this process and patients defense immune factors. LILT has shown an anti-inflammatory activity, improving the periapical repair process. This in vitro study aimed to analyze the effect of LILT at the secretory activity of macrophages previously activated by interferon-gamma and lypopolisaccharide from E.coli, and stimulated by substances leached from three endodontic sealers (zinc oxide-eugenol based, resinous and calcium hydroxide-based). Cytotoxicity of these substances was assessed by the MTT test. Activated macrophages were stimulated by the substances or not (control) and then, irradiated or not (control) and the secretion of pro-inflammatory proteins (interleukin-1 b, tumor necrosis factor-a and matrix metalloproteinase-1) was analyzed by ELISA test. The LILT was performed using a GaAlAs laser (780 nm, 70 mW, focal spot of 4.0 mm2, 1.67 sec, 3 J/cm2). Two irradiations with 6 h-intervals were done. The data was compared by either ANOVA test or Friedmans test. The cell viabilities of controls and cells treated by the sealers were similar. Production of IL -1 b and TNF-a were observed. There was a high production of MMP-1. However, statistical differences were not observed amongst the groups. The irradiated groups presented results similar to those of non irradiated groups. Substances leached from the endodontic sealers are non cytotoxic at these experiments conditions . These substances, as well as the LILT, at the parameter used, were not able to change the secretion of MMP-1, IL-1 b e TNF-a by activated macrophages.
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Papel do fator de transcrição AP-1 na hipernocicepção neuropática em camundongos / Role of the AP-1 transcription factor in neuropathic hypernociception in mice.Rafael Poloni 24 February 2014 (has links)
A dor neuropática pode ser causada por lesões e/ou disfunções no sistema somatossensorial. Nestes tipos de dores, alterações plásticas ao longo de todo o sistema sensorial nociceptivo estão associadas à cronificação do processo doloroso. A plasticidade observada pode ser resultante da indução e/ou repressão de genes, os quais geralmente são modulados por fatores de transcrição. Um dos principais fatores de transcrição até então conhecido é a proteína ativadora-1 (AP-1), que pode ser estruturalmente formado principalmente por proteínas das famílias Jun e Fos. Entretanto, na dor neuropática, a participação e o papel do AP-1 não estão bem elucidados. Dessa forma, a hipótese deste trabalho é que a ativação do AP-1 contribua para a indução e/ou manutenção da dor neuropática, através da ativação de células gliais e de proteinocinases ativadas por mitógenos (MAPK) e por indução da produção e liberação de mediadores pró-inflamatórios, bem como de metaloproteinases da matriz extracelular (MMP) na medula espinal. Esses fatores contribuem para sensibilização central causada pela SNI, facilitando a transmissão dolorosa. Assim, a inibição do AP-1 seria uma potencial estratégia terapêutica no tratamento da dor neuropática. Foi utilizado o modelo experimental de dor neuropática de lesão limitada do nervo isquiático (SNI, Spared Nerve Injury) em camundongos, os quais receberam injeção intratecal (i.t.) do inibidor de AP-1, SR11302, ou seu veículo (DMSO, tween® 20 e salina). O tratamento com o inibidor de AP-1 reduziu a hipernocicepção mecânica causada pela SNI, e o perfil de redução sugeriu que esse fator de transcrição esteja relacionado com a manutenção da dor neuropática. No sétimo dia após a SNI, observou-se na medula espinal dos camundongos, ativação da microglia, dos astrócitos e das MAPK, além de aumento na expressão de TNF-, interleucina (IL)-6, IL-1, IL-17A, quimiocina derivada de queratinócito (KC), proteína quimiotáxica de monócitos (MCP-1), óxido nítrico (NO), NO sintase induzível e das MMP-2 e -9. Todos esses eventos estão associados à sensibilização central, portanto, contribuem para a facilitação da transmissão nociceptiva. O tratamento com o inibidor de AP-1 SR11302 impediu, pelo menos parcialmente, a ativação das células gliais e das MAPK e bloqueou o aumento na expressão de todos esses mediadores pró-inflamatórios e das MMPs na medula espinal. Assim, o fator de transcrição AP-1 e, consequentemente, suas vias a jusante (downstream) são potenciais alvos farmacológicos no tratamento da dor neuropática. / Neuropathic pain results from nerve damage or dysfunction, which is associated to the painful process of chronification. This process may include participation of the inducible genes, which may be modulated by transcription factors, including the activator protein-1 (AP-1), which can structurally be formed by proteins from Jun and Fos families. However, the participation and the role of AP-1 neuropathic pain remain unclear. Our hypothesis is that the activation of AP-1 would contribute for the induction and/or maintenance of neuropathic pain, by inducing the glial cells activation and mitogen-activated protein kinases, and by inducing the production/release of pro-inflammatory mediators and extracellular matrix metalloproteinase (MMP) in mices spinal cord. All these factors are contributing to SNI-evoked central sensitization, facilitating pain transmission. Thus, inhibition of AP-1 would be a potential drug target in the treatment of neuropathic pain. The animals received inhalatory anesthesia (2% isoflurane) and were submitted to an experimental model of neuropathic pain Spared Nerve Injury (SNI). The animals were treated intrathecally (i.t.) with AP-1 inhibitor SR11302 or vehicle (DMSO, tween®20 and saline). Treatment with AP-1 inhibitor reduced the SNI-induced mechanical hypernociception, suggesting that this transcription factor is related to the maintenance of neuropathic pain. On the seventh day after SNI, there was in the spinal cord of mice microglia, astrocytes and MAPK activation, increased of expression of TNF-, interleukin (IL)-6, IL-1, IL-17A, keratinocyte-derived chemokine (KC), monocyte chemoattractant protein-1 (MCP-1), nitric oxide (NO) and inducible NO synthase, and increased the expression of MMP-2 and -9. All of these effects are related with central sensitization, thus facilitating nociceptive transmission. However, treatment with SR11302 prevented, at least partially, activation of MAPK and glial cells, as well as prevented the increase in expression of all these pro-inflammatory mediators and MMPs in the spinal cord. Thus, inhibition of AP-1 and hence its way downstream is a potential pharmacological target in the treatment of neuropathic pain.
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Étude de l’expression des cytokines et métalloprotéases dans les tissus péri-implantaires inflammatoires et rôle potentiel du titane dans les péri-implantites / Cytokines & metalloproteases expression in peri-implant inflammatory tissues and the potential involvement of titanium in peri-implantitisGhighi, Maxime 04 December 2017 (has links)
Les péri-implantites se caractérisent par une destruction inflammatoire irréversible des tissus qui entourent l’implant dentaire. Leur pathogénie est proche des parodontites, maladies inflammatoires chroniques d’étiologie bactérienne entrainant une destruction irréversible de l’os alvéolaire soutenant les dents. Cependant, la réponse inflammatoire et la résorption osseuse diffèrent entre péri-implantites et parodontites. De plus, les traitements conventionnels non chirurgicaux ne sont pas efficaces pour le traitement des péri-implantites. L’objectif de notre travail est d’analyser les différences entre les médiateurs inflammatoires et cataboliques des tissus péri-implantaires en comparaison aux tissus parodontaux malades après une thérapie conventionnelle non chirurgicale. Nous avons bâti une collection biologique d’explants humains de tissus conjonctifs péri-implantaires ou parodontaux malades. Une analyse Multiplex des milieux conditionnés et histologiques des explants a révélé une expression accrue de l’inhibiteur de métalloprotéase TIMP-2, de l’interleukine IL-10 et du RANK-L dans les tissus péri-implantaires. En accord avec une revue de littérature que nous avons mené dans la seconde partie de notre travail, notre hypothèse est que ces différences s’expliqueraient, tout du moins en partie, par la présence de particules de titane au niveau des tissus péri-implantaires. Notre travail participe à la compréhension de la pathogenèse de la maladie et concourt à l’identification de biomarqueurs potentiels pour le pronostic ou le développement d’approches thérapeutiques. / Peri-implantitis lesions present an irreversible destruction of the peri-implant surrounding tissues. The pathogenic pathway of peri-implantitis is close from the one of periodontitis which is a chronic inflammatory disease caused by a bacterial biofilm leading to irreversible supportive bone destruction around teeth. Still, the inflammatory process and the bone destruction differ between the two diseases. In addition, conventional non-surgical treatments are not effective for the treatment of peri-implantitis. The aim of our work is to analyze the differences between inflammatory and catabolic mediators of peri-implant tissues compared to diseased periodontal tissues after conventional non-surgical therapy. We have constructed a biological collection of human explants of peri-implant or periodontal connective tissue. Multiplex assays of the conditioned media and histological analysis of the explants revealed an increased expression of the TIMP-2 metalloprotease inhibitor, interleukin IL-10, and RANK-L in the peri-implant tissues. In agreement with a review of literature that we conducted in our work, our hypothesis is that these differences can be explained, at least partly, by the presence of titanium wear particles in the peri-implant tissues. Our work contributes to the understanding of the pathogenesis of the disease and contributes to the identification of biomarkers.
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Laboratory and modelling studies on the effects of injection gas composition on CO₂-rich flooding in Cooper Basin, South Australia.Bon, Johannes January 2009 (has links)
This Ph.D. research project targets Cooper Basin oil reservoirs of very low permeability (approximately 1mD) where injectivities required for water flooding are not achievable. However, the use of injection gases such as CO₂ would not have injectivity problems. CO₂ is abundant in the region and available for EOR use. CO₂ was compared to other CO₂-rich injection gases with a hydrocarbon content including pentane plus components. While the effect of hydrocarbon components up to butane have been investigated in the past, the effect of n-pentane has on impure CO₂ gas streams has not. One particular field of the Cooper Basin was investigated in detail (Field A). However, since similar reservoir and fluid characteristics of Field A are common to the region it is expected that the data measured and developed has applications to many other oil reservoirs of the region and similar reservoirs elsewhere. The aim of this Ph.D. project is to determine the applicability of CO₂ as an injection gas for Enhanced Oil Recovery (EOR) in the Cooper Basin oil reservoirs and to compare CO₂ with other possible CO₂-rich injection gases. The summarised goals of this research are to: • Determine the compatibility of Field A reservoir fluid with CO₂ as an injection gas. • Compare CO₂ to other injection gas options for Field A. • Development of a correlation to predict the effect of nC₅ on MMP for a CO₂- rich injection gas stream. These goals were achieved through the following work: • Extensive experimental studies of the reservoir properties and the effects of interaction between CO₂-rich injection gas streams and Field A reservoir fluid measuring properties related to: • Miscibility of the injection gas with Field A reservoir fluid • Solubility and swelling properties of the injection gas with Field A reservoir fluid • Change in viscosity-pressure relationship of Field A reservoir fluid due to addition of injection gas • A reservoir condition core flood experiment • Compositional simulation of the reservoir condition core flood to compare expected recoveries from different injection gases • Development of a set of Minimum Miscibility Pressure (MMP) measurements targeted at correlating the effect of nC₅ on CO₂ MMP. The key findings of this research are as follows: • Miscibility is achievable at practical pressures for Field A and similar reservoir fluids with pure CO₂ or CO₂-rich injection gases. • For Field A reservoir fluid, viscosity of the remaining flashed liquid will increase at pressures below ~2500psi due to mixing the reservoir fluid with a CO₂-rich injection gas stream. • Comparison of injection gases showed that methane rich gases are miscible with Field A so long as a significant quantity of C₃+ components is also present in the gas stream. • There is a defined trend for effect of nC₅ on MMP of impure CO₂. This trend was correlated with an error of less than 4%. • Even though oil composition is taken into account with the base gas MMP, it still affects the trend for effect of nC₅ on MMP of a CO₂-rich gas stream. • An oil characterisation factor was developed to account for this effect, significantly improving the results, reducing the error of the correlation to only 1.6%. The significance of these findings is as follows: • An injection pressure above ~3000psi should be targeted. At these pressures miscibility is achieved and the viscosity of the reservoir fluid injection gas mix is reduced. • CO₂ should be compared to gases such as Tim Gas should after considering the cost of compression, pipeline costs and distance from source to destination will need to be considered. • The addition of nC₅ will reduce the MMP and increase the recovery factor, however the cost of the nC₅ used would be more than the value of increased oil recovered. • The developed correlation for the effect of nC₅ on impure CO₂ MMP can be used broadly within the limits of the correlation. • Further research using more oils is necessary to validate the developed oil characterisation factor and if successful, using the same or similar method used to improve other correlations. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1369016 / Thesis (Ph.D.) -- University of Adelaide, Australian School of Petroleum, 2009.
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Pathogenese der equinen Endometrose: Bedeutung der Wachstumsfaktoren Transforming growth factor-alpha, -beta1, -beta2 und -beta3 sowie der Matrixmetalloproteinase-2.Kiesow, Claudia 10 February 2011 (has links) (PDF)
Ziel der vorliegenden Arbeit war die immunhistologische Charakterisierung der Expression der profibrotischen Wachstumsfaktoren Transforming growth factor-beta-1, -beta2 und -beta3 und des Enzyms Matrixmetalloproteinase-2 (MMP-2) im equinen Endometrium während des Zyklus sowie innerhalb der verschiedenen Erscheinungsformen der equinen Endometrose. Zudem wurde der potentielle Einfluss einer gleichzeitig auftretenden Endometritis auf die glanduläre und stromale Wachstumsfaktor- und Enzym-Expression untersucht. Die Ergebnisse dieser Studie sollten klären, ob und inwieweit den untersuchten Wachstumsfaktoren unter Beteiligung von MMP-2 in der Pathogenese der equinen Endometrose eine mit anderen Organfibrosen vergleichbare Schlüsselrolle zukommt.
Zu diesem Zweck standen an definierten Tagen entnommene Endometriumbioptate (n=21) von drei zyklisch aktiven, klinisch und gynäkologisch gesunden Maidenstuten sowie Endometriumbioptate von 60 Stuten mit graduell variabler Endometrose unterschiedlichen Charakters und Endometriumbioptate von 22 Stuten mit mittelgradiger Endometrose und gleichzeitiger mittelgradiger eitriger (n=16) bzw. nichteitriger (n=6) Endometritis aus dem Routineeinsendungsmaterial des Institutes für Veterinär-Pathologie der Universität Leipzig zur Verfügung.
Die Wachstumsfaktoren TGF-beta1, -beta2 und -beta3 sowie das Enzym MMP-2 zeigen im Zyklus ein typisches, zellspezifisches Reaktionsmuster, das unterschiedlichen Regulations-mechanismen zu unterliegen scheint. Ein Maximum der TGF-beta1-Expression in den luminalen Epithelzellen, Stroma- und Drüsenzellen kann in der endometrialen Sekretionsphase mit Anstieg bzw. einem Maximum der Serumprogesteron-Konzentration beobachtet werden. Im Gegensatz dazu tritt eine Expression von MMP-2 in den Stromazellen in der Sekretionsphase mit Abfall der Progesteronkonzentration im Serum auf. Das luminale Epithel und die Stromazellen zeigen eine maximale Expression von TGF-beta2 beim Vorliegen hoher Progesteronspiegel im Serum bzw. mit Abfall der Serumprogesteron-Konzentration in der Sekretionsphase. TGF-beta3 weist im luminalen Epithel ein ähnliches Expressionsmuster auf, eine deutliche Abhängigkeit zu den Serumhormon-Konzentrationen lässt sich jedoch nicht feststellen. Die stromale Expression von TGF-alpha unterliegt im equinen Endometrium keinen zyklusabhängigen Variationen.
Die Stromazellen innerhalb der verschiedenen Endometroseherde zeigen, im Vergleich zum unveränderten Endometrium, vor allem eine verminderte Expression von TGF-alpha. Das Expressionsmuster der TGF-beta-Wachstumsfaktoren ist grundsätzlich variabel, es fällt jedoch auf, dass die Stromazellen insbesondere in inaktiven Endometrosen eine geringere Expression der TGF-beta-Isoformen aufweisen. Ursache ist möglicherweise eine gestörte hormonelle Stimulation bzw. eine stromale Synthesestörung in Folge veränderter epithelial/stromaler Wechselwirkungen. Das Enzym MMP-2 wird dagegen in den Stromazellen aller Endometroseherde, unabhängig von deren Differenzierung und dem Auftreten glandulärer Alterationen, deutlich vermehrt nachgewiesen. Dies ist sehr wahrscheinlich Folge der Extra-zellularmatrix-Akkumulation innerhalb der Endometroseherde und für die fortschreitende Zerstörung der glandulären Basalmembranen verantwortlich. Die glanduläre Expression innerhalb der Endometroseherde gleicht weitgehend der der unveränderten Drüsenzellen, lediglich in destruierenden Endometrosen werden TGF-alpha, TGF-beta2 und MMP-2 in den involvierten Drüsenzellen vermehrt nachgewiesen. Mögliche Ursachen wären eine Diffusion durch die geschädigte glanduläre Basalmembran bzw. eine Anregung der Synthese im Rahmen der epithelialen Wundheilung. Eine Anregung der glandulären und stromalen Expression der untersuchten Wachstumsfaktoren und des Enzyms MMP-2 im Rahmen der Endometrose durch die Anwesenheit von Entzündungszellen konnte nicht nachgewiesen werden.
Eine der Leber- und Lungenfibrose ähnelnde, überschießende Wundheilungsreaktion durch eine primär epithelial bedingte, vermehrte TGF-Wachstumsfaktorproduktion sowie direkte Zusammenhänge zwischen der MMP-2- und TGF-beta-Wachstumsfaktor-Expression waren in der equinen Endometrose nicht festzustellen. Da vor allem die Stromazellen in der Endometrose eine veränderte Expression der Wachstumsfaktoren aufwiesen, ist möglicherweise eine primäre stromale Fehldifferenzierung der Ausgangspunkt für die Entstehung der Endometrose. Eine mit der Leber- und Lungenfibrose vergleichbare Schlüsselrolle der TGF-Wachstumsfaktoren in der Pathogenese der equinen Endometrose konnte nicht eindeutig belegt werden.
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Epigenetische Beeinflussung der Proliferation, Expression von Matrix-Metalloproteinasen, Migration und Invasion von Harnblasenkarzinomzelllinien / Epigenetic influence on proliferation, expression of matrix-metalloproteinases, migration and invasion of bladder cancer cell linesKosz, Magdalena 01 June 2010 (has links)
No description available.
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Untersuchungen zur Expression der zellzyklusassoziierten Proteine p27Kip1 und Ki-67 und der Matrixmetalloproteinaseinhibitoren TIMP-1, TIMP-2 und TIMP-3 in häufigen humanen Karzinomen / Cell-cycle associated proteins p27Kip1 and Ki-67 and metalloproteinases TIMP-1, TIMP-2 and TIMP-3 in human carcinomaHuber, Julia 01 March 2011 (has links)
No description available.
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Rôle de l’axe CD40L/CD40 dans les cellules endothéliales progénitricesBou Khzam, Lara 08 1900 (has links)
Les cellules endothéliales progénitrices («Endothelial Progenitor Cells», EPCs) sont
des précurseurs endothéliaux qui possèdent un potentiel considérable dans la réparation et la
régénération vasculaire. Dans le contexte des maladies cardiovasculaires, la compréhension
du rôle des EPCs dans la régulation de la thrombogenèse et la réparation endothéliale est
pertinente et nécessaire pour comprendre leur potentiel thérapeutique.
Nous avons rapporté que les EPCs interagissent avec les plaquettes via la P-sélectine
et inhibent l’adhésion, l’activation et l’agrégation des plaquettes ainsi que la formation de
thrombus. Plus récemment, nous avons démontré que les EPCs expriment le récepteur
inflammatoire CD40 et il est bien connu que les plaquettes constituent la source principale
de la forme soluble de son agoniste le CD40L («soluble CD40 Ligand», sCD40L). Ainsi,
nous avons émis l’hypothèse principale que l’axe CD40L/CD40 dans les EPCs influence
leurs fonctions anti-thrombotique et pro-angiogénique.
Pour vérifier cette hypothèse, nous avons réussi à générer des «early» et «late» EPCs
à partir de cellules mononucléaires du sang périphérique («Peripheral Blood Mononuclear
Cells», PBMCs) en culture. Nous avons mis en évidence l’existence de l’axe CD40L/CD40
dans ces EPCs en démontrant l’expression des protéines adaptatrices, nommées les facteurs
associés au récepteur du facteur de nécrose tumorale («TNF Receptor Associated Factors»,
TRAFs). Dans une première étude, nous avons investigué l’effet du sCD40L sur la fonction
des «early» EPCs dans l’agrégation plaquettaire. En effet, nous avons démontré que le
sCD40L renverse leur effet inhibiteur sur l’agrégation plaquettaire, et ce sans avoir un effet
significatif sur la sécrétion de prostacycline (PGI2) et d’oxyde nitrique («Nitric Oxide», NO)
par ces cellules. De plus, aucun effet du sCD40L n’a été noté sur l’apoptose et la viabilité de
ces cellules. Par contre, nous avons noté une augmentation importante du stress oxydatif
dans les «early» EPCs suite à leur stimulation avec le sCD40L. L’inhibition du stress
oxydatif renverse l’effet du sCD40L sur les «early» EPCs dans l’agrégation plaquettaire.
Ces résultats pourraient expliquer, en partie, la fonction réduite des EPCs chez les individus
présentant des niveaux élevés de sCD40L en circulation.
Dans une deuxième étude, nous avons étudié l’effet de sCD40L dans la fonction des
«early» EPCs en relation avec l’angiogenèse. Nous avons identifié, dans un premier temps,les métalloprotéinases de la matrice («Matrix Metalloproteinases», MMPs) qui sont
sécrétées par ces cellules. Nous avons trouvé que les «early» EPCs relâchent principalement
la MMP-9 et que cette relâche est augmentée par le sCD40L. Le sCD40L induit aussi la
phosphorylation de la p38 MAPK qui contribue à augmenter la sécrétion de MMP-9. Des
études fonctionnelles ont démontré que le prétraitement des «early» EPCs au sCD40L
potentialise la réparation endothéliale des HUVECs.
En conclusion, l’ensemble de nos travaux, dans le cadre de ce projet de doctorat,
nous a permis d’élucider les mécanismes responsables de l’action du sCD40L sur les effets
inhibiteur et angiogénique des «early» EPCs dans l’agrégation plaquettaire et l’angiogenèse,
respectivement. Ces résultats ajoutent de nouvelles connaissances sur le rôle des EPCs et
pourront constituer la base pour des études futures permettant de corréler les niveaux élevés du sCD40L circulant et l’incidence des maladies cardiovasculaires, particulièrement
l’athérothrombose. / Endothelial progenitor cells (EPCs) are endothelial precursors which possess a
considerable therapeutic potential in vascular repair and regeneration. In the context of
cardiovascular diseases, the understanding of the role of EPCs in the regulation of
thrombogenesis and endothelial repair is relevant and necessary to the understanding of their
therapeutic potential.
We have shown that EPCs interact with platelets via P-selectin and inhibit the
adhesion, activation and aggregation of platelets as well as thrombus formation. Recently,
we have shown that EPCs express the inflammatory receptor CD40 and it is well known that
platelets are the main source of the soluble form of its agonist CD40L («soluble CD40
ligand», sCD40L). Hence, we have hypothesized that the CD40L/CD40 axis in EPCs
influences the anti-thrombotic and pro-angiogenic functions of EPCs.
To verify this hypothesis, we have successfully generated early and late EPCs from
peripheral blood mononuclear cells in culture. We have demonstrated the existence of the
CD40L/CD40 axis in EPCs by showing the expression of adaptor proteins, named tumor
necrosis factor associated factors (TRAFs). In our first study, we investigated the effect of
sCD40L on the function of early EPCs in platelet aggregation. Indeed, we have shown that
sCD40L reverses their inhibitory effect on platelet aggregation without having an effect on
prostacyclin (PGI2) and nitric oxide (NO) secretion by these cells. Moreover, no effect of
sCD40L has been noted on the apoptosis and viability of these cells. However, we have
shown a significant increase in oxidative stress in early EPCs following sCD40L
stimulation. The inhibition of oxidative stress reverses the effect of sCD40L on early EPCs
in platelet aggregation. These results could partially explain the decreased function of EPCs
in individuals displaying higher levels of sCD40L in circulation.
In our second study, we have studied the effect of sCD40L on the function of early
EPCs in relation to angiogenesis. First, we have identified the matrix metalloproteinases
(MMPs) which are secreted by these cells. We have found that early EPCs mainly release
MMP-9 and that this release is increased by sCD40L. The sCD40L also induces the
phosphorylation of p38 MAPK which contributes to increase the secretion of MMP-9. In functional studies, we have shown that pretreatment of early EPCs with sCD40L can
potentialize HUVEC endothelial repair.
In conclusion, our work in the context of this doctoral research project has allowed
us to study the mechanisms involved in the role of sCD40L in the inhibitory and angiogenic
function of early EPCs in platelet aggregation and angiogenesis, respectively. These results
add new insights to the role of EPCs and could constitute the basis for future studies
allowing for the correlation between high levels of sCD40L and the incidence of
cardiovascular disease, particularly atherothrombosis.
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