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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.
21

The Effects of Matrix Metalloproteinase-9 on CX3CL1 Shedding and Axon Retraction

Dobrie, Lauren A 01 January 2019 (has links)
Spinal cord injury (SCI) often leads to irreversible damage, and permanent paralysis inferior to the injury is common (Leibinger et al., 2013). Injury to the spinal cord occurs in two phases. In the first phase, components of the spinal cord are subject to mechanical trauma causing direct damage. In the second phase, damage spreads from the area of injury through molecular processes. Several studies have linked M1 "pro-inflammatory" macrophages to exacerbation of damage by inducing dieback of dystrophic axons, but not healthy axons, through direct cellular contact. Several studies have identified the presence of macrophage subtypes at specific time. A literature review was conducted in order to summarize these findings (Busch, Horn, Silver, & Silver, 2009; Evans et al., 2014; Horn, Busch, Hawthorne, van Rooijen, & Silver, 2008; Kigerl et al., 2009; Shechter et al., 2013). Although the full mechanism behind the process of M1 macrophage-mediated dieback of dystrophic axons is unclear, matrix metalloproteinase-9 (MMP-9) produced by these macrophages has been shown to play a role. However, the specific interaction between MMP-9 and neurons is under investigation. The research described explores the relationship between MMP-9 and fractalkine (CX3CL1), a surface protein expressed by CNS neurons. SDS-PAGE and western blot were used to determine whether the presence of MMP-9 increases the cleavage of fractalkine at several time intervals. At a concentration of 300ng/ml, MMP-9 was not found to demonstrate cleavage of fractalkine.
22

Implication du syndécan-1 dans la migration des kératinocytes / Syndecan-1 involvement in keratinocyte migration

Montmasson, Marine 20 December 2018 (has links)
Au cours de la réparation cutanée, l’étape de réépithélialisation est essentielle car son objectif est de restaurer la fonction barrière de la peau. Elle consiste en une série d’étapes coordonnées où les kératinocytes migrent, prolifèrent et se différencient jusqu’à restauration complète de l’épiderme. Régulée de façon simultanée au niveau intracellulaire mais également extracellulaire, elle dépend de la production de facteurs de croissance, de métalloprotéases matricielles (MMPs) et de protéines de la matrice extracellulaire sur lesquelles les kératinocytes adhèrent et migrent par l’intermédiaire de récepteurs de la famille des intégrines ou des syndécans. Parmi les ligands matriciels, la laminine 332 (LN332), qui est connue comme étant la protéine d’adhésion majeure des kératinocytes de l’épiderme, s’avère être également impliquée au cours de la réépithélialisation et jouer un rôle important dans les processus d’adhésion et de migration des kératinocytes, notamment par le biais de son domaine globulaire LG4/5 localisé à l’extrémité C-term de sa chaine 3. De récentes études ont montré que ce domaine LG4/5 induit la migration des kératinocytes normaux humains (NHK), impliquant des MMPs pro-migratoires MMP-1 et MMP-9. Puisque les domaines LG4/5 ont été montrés comme participant à la dynamique du cytosquelette et au mouvement cellulaire par le biais des récepteurs syndécan-1 et -4, mon laboratoire d’accueil a décidé d’étudier l’implication du récepteur syndécan-1 dans ce processus d’expression de la MMP-9. Les analyses PCR et les résultats de zymographie obtenus ont révélé que le syndécan-1 joue un rôle dans l’expression et l’activation de la MMP-9 induite par le domaine LG4/5. De plus, la déplétion de l’expression du syndécan-1 dans les NHK a confirmé ces résultats. De précédents résultats de mon laboratoire d’accueil ont montré que le domaine LG4/5 induit la formation de filopodes médiée par le syndécan-1 au niveau du front de migration des kératinocytes. De ce fait, nous avons effectué des zymographies de gélatine in situ chez des NHK en migration afin d’observer la localisation de la MMP-9 et de savoir si cette dernière était trouvée au niveau de ces structures d’adhésion protrusives. Nous avons observé des zones de digestion de gélatine sous les NHK ressemblant à des points de contact d’adhésion. Leur nombre est augmenté chez des NHK traités avec le domaine LG4/5 de la LN332. L’utilisation d’inhibiteurs spécifiques des gélatinases et de la MMP-9 ont révélé que cette dernière est responsable de la formation de ces zones de digestion de gélatine. Parce que ces structures évoquent des podosomes, nous avons décidé de révéler leurs constituants majoritaires, à savoir la cortactine, la vinculine, l’-actinine, VASP, WASP ou encore Arp2/3. Dans le même temps nous avons également révélé le syndécan-1 afin de voir si ce dernier était présent dans ces structures. Nos résultats ont montré que tous les marqueurs des podosomes étaient localisés soit sous la forme d’un point à l’intérieur des zones de digestion pour les protéines régulatrices de l’actine, soit sous la forme d’un anneau entourant les zones de digestion pour les protéines d’adhésion et de signalisation associées à la membrane, confirmant donc que les structures observées sont bien des podosomes. Le syndécan-1 apparaît également sous une forme d’anneau, entourant les protéines régulatrices de l’actine et les zones de digestion laissant penser que le syndécan-1 serait impliqué dans ces structures. La diminution de l’expression du syndécan-1, en utilisant l’approche des petits ARN interférents dans des NHK, a montré que l’absence de syndécan-1 diminue de façon drastique le nombre et la surface des zones digérées. L’ensemble de nos résultats montre que le syndécan-1 serait un constituant des podosomes des kératinocytes, participant à leur formation et jouant un rôle dans le contrôle de l’expression de la MMP-9 / During skin repair, the reepithelialization step is essential to restore the skin barrier function. lt occurs by an orderly series of events whereby keratinocyte migrate, proliferate and differentiate until complete epidermal restoration. Keratinocyte migration determines the efficiency of the overall wound repair process. The keratinocyte's migratory behavior depends on the production of growth factors, matrix metalloproteinases (MMP) and on the dynamic interactions of the cells with extracellular components. Laminin 332 (LN332), known as a major adhesion substrate for keratinocytes, was shown to contribute to skin reepithelialization through its a3 chain C-terminal domains LG4/5. Recent studies have reported that LG4/5 induces keratinocyte migration, an event that relies on the involvement of the pro-migratory MMP-1 and MMP-9. As LG4/5 domains were shown to participate in cytoskeleton dynamic and cell movement through binding of the heparan sulfate proteoglycans syndecan-1 and -4, we analyzed the potential involvement of these receptors in this process. The PCR analysis and zymography results revealed that syndecan-1 plays a role in LG4/5 induced MMP-9 expression and activation. Down regulating or overexpressing syndecan-1 expression in cells confirmed these findings. As LG4/5 was shown to induce the formation of syndecan-1-mediated filopodia at the front of migrating cells, we performed in situ zymography experiments in migrating keratinocyte to analyze whether MMP-9 is found in these protrusive adhesion structures. Very interestingly, we found areas of digested gelatin resembling adhesion contacts underneath keratinocytes. Their number was increased in LG45-treated keratinocytes, a result in line with our previous data. The use of specific MMP inhibitors revealed that MMP-9 is responsible for the formation of these digested gelatin clusters. Further confocal microscope analysis revealed, at the cellular level, the presence of actin located within the digested areas, suggesting that an adhesion receptor would be involved in this process. Because these structures resemble podosomes, we revealed major podosome components, such as cortactin, vinculin, -actinin, VASP, WASP, Arp2/3 or dynamin and integrin. Our results showed all the podosome markers either within the digested areas (regulatory actin proteins) or organized as ring encircling the digested areas (signaling and adhesion proteins associated with plasma membrane), confirming that these structures are podosomes. Syndecan-1 also appears as a ring around the digested areas and encircling the regulatory actin proteins, suggesting that this receptor could be involved in these structures. The syndecan-1 depletion in normal human keratinocytes with specific siRNAs drastically decreased the digested areas surface. Taken together, our data demonstrate that syndecan-1 is a podosome components, participating in their formation and playing a role in MMP-9 expression and deposition. These results suggest that its re-distribution at the front edge of migrating keratinocyte may have a role to play in the cleavage or degradation of extracellular matrix proteins therefore facilitating their path through the fibrin clot
23

Matrix metalloproteinases as potential target in the treatment of vascular dysfunctions / Métalloprotéinases matricielles comme cibles thérapeutiques potentielles dans le traitement des dysfonctionnements vasculaires

Shamseddin, Aly 16 December 2016 (has links)
L’endothélium préserve l'homéostasie vasculaire et tissulaire qui contrôle plusieurs processus physiologiques dans les corps humain. Lors de certaines pathologies, l'intégrité vasculaire peut être perturbée par une diversité de médiateurs de perméabilité qui interrompent la fonction barrière de cet épithélium, et provoquer des lésions tissulaires au cours de la progression de la maladie. Par conséquent, l'intégrité de la barrière endothéliale est essentielle pour l'homéostasie vasculaire. Dans le cas de la fièvre hémorragique due à la dengue, de nombreuses voies de signalisation induisent une perméabilité vasculaire qui résulte d'une rupture de la barrière hémato-encéphalique qui, dans certains cas, peuvent permettre la pénétration virale dans le système nerveux central (SNC). La plupart de ces voies de signalisation (y compris le TNF-alpha) sur-activent les enzymes appelées métalloprotéinases matricielles (MMP), qui induisent la dégradation de la matrice extracellulaire (MEC) et des protéines intercellulaires régissant la perméabilité vasculaire. Parmi ces enzymes, les MMP gélatinolytiques (MMP-9 et MMP-2) sont considérées comme la classe la plus importante de MMP puisqu'elles sont capables de dégrader le collagène de type IV, constituant principal de la MEC, et les jonctions cellulaires PECAM- 1 et VE-cadhérine. Ainsi, dans cette étude, nous avons développé deux approches pour inhiber l'activité de MMP-9 et protéger la perméabilité vasculaire in vitro. Ces approches incluent (i) des antagonistes de MMP-9 conçus in silico, tels que le composée HA048 (ii) des composés lipophénoliques synthétiques dérivés du resvératrol. Ce dernier existe naturellement dans les tiges de raisin, les arachides et plusieurs autres plantes et qui est capable d'inhiber l'expression et l'activité de la MMP-9. Bien que le resvératrol ait plusieurs activités biologiques testées in vitro, son utilisation dans des modèles animaux est limitée en raison de sa faible biodisponibilité, de son métabolisme rapide et de son élimination. Par conséquent, cette étude a trois objectifs principaux. Premièrement, de trouver un nouveau composé capable d'inhiber l'activité de MMP-9 in vitro. Deuxièmement, de vérifier s’il peut protéger l'intégrité de la couche endothéliale dans les HUVEC. Enfin, de passer à des études précliniques sur le modèle de souris dengue afin de vérifier son activité, sa toxicité et sa biodisponibilité. Outre le resvératrol et le SB-3CT (inhibiteur commercial de la MMP-9), nous avons constaté que le resvératrol-acide linoléique oméga 6 (RES-LA), le resvératrol-docosanoïque (RES-C22) et le HA048 ont montré la plus forte activité anti-MMP-9 parmi d'autres composés. Cependant, RES-LA a été préférentiellement choisi par rapport à RES-C22 en raison de sa meilleure solubilité. Par conséquent, nous avons utilisé un nouveau concept de formulation de ces composés en les solubilisant dans un solvant compatible et moins toxique pour des expériences in vivo, un solvant eutectique profond naturel (NADES), composé de 1,2-propanediol:ChCl: eau (1:1:1) (NADES/PCW). Les résultats de la perméabilité vasculaire in vitro ont révélé que les inhibiteurs de la MMP-9 ont diminué la perméabilité endothéliale exacerbée induite par le TNF-α dans les HUVEC, mesurée à la fois en temps réel et en fluorescence. En outre, l'examen microscopique des jonctions cellulaires adhérentes a montré qu’il y avait plus de CD31/PECAM-1 entre les HUVEC traitées à la fois par le TNF-α et les inhibiteurs de la gélatinase par rapport au témoin positif (TNF-alpha).Le mécanisme d'action des lipophénols dérivés du resvératrol a été évalué. Nos résultats ont révélé que les lipophénols dérivés du resvératrol ont inhibé l'expression de la MMP-9 en atténuant la phosphorylation des kinases MAPK ERK1/2 et JNK1/2. / The endothelial barrier preserves the vascular and tissue homeostasis that controls several physiological processes inside the body. In pathologies, vascular integrity could be disrupted by a diverse of permeability mediators that interrupt the barrier function and cause tissue damage during disease progression. Therefore, endothelial barrier integrity is critical for vascular homeostasis. Although the mechanisms leading to vascular leakage have been studied over several past decades, recent approaches have pointed new therapeutic targets in pre-clinical studies. In the pathogenesis of dengue hemorrhagic fever (DHF), many signaling pathways induce vascular permeability that result of disruption of blood brain barrier, that in some cases could allow viral penetration into the central nervous system (CNS). Most of these signaling pathways (including TNF-alpha) activate the overproduction active enzymes called matrix metalloproteinases (MMPs) that induce degradation of the extracellular matrix (ECM) and intercellular proteins governing vascular permeability. Among these enzymes, gelatinolytic MMPs, (MMP-9 and MMP-2), which are considered the most important class of MMPs since they are capable of degrading collagen type-IV, the main constituent of ECM, and cell junctions (PECAM-1 and VE-cadherin). Thus, in this study, we have developed two approaches to inhibit MMP-9 activity and protect the vascular permeability in vitro. Those approaches include, (i) in silico designed MMP-9 antagonists, where we had determined a lead MMP-9 blocker (HA048). The second approach is to synthesize derived lipophenolic compounds from resveratrol, that naturally exists in grape stalks, peanuts, and several other plants, which is capable of inhibiting the expression and activity of active MMP-9 inside the cells. Despite that resveratrol has several biological activities tested in vitro, its use in animal models is limited due to its poor bioavailability, rapid metabolism, and elimination. Therefore, this study has three main goals. First, is to find a novel compound capable of inhibiting MMP-9 activity in vitro. Second, is to verify whether it can preserve the endothelial monolayer integrity. Finally, is to move to the preclinical studies in dengue mouse model to verify its activity in vivo, toxicity, and bioavailability.Besides resveratrol and SB-3CT (commercial MMP-9 inhibitor), we found that resveratrol-linoleic acid, omega-6 (RES-LA), resveratrol-Docosanoic acid (RES-C22) and HA048 (in silico designed inhibitor) have demonstrated the highest MMP-9 inhibitory activity among dozens of synthesized compounds. However, RES-LA was preferably selected over RES-C22 due to for solubility reasons. Moreover, we formulated these compounds in novel solvents that could be compatible and less toxic for in vivo experiments, which is known as natural deep eutectic solvent (NADES) based on 1,2-propanediol:ChCl:water (1:1:1) (NADES/PCW).Results of in vitro vascular permeability revealed that MMP-9 inhibitors have decreased TNF-α induced-exacerbated endothelial permeability in HUVEC, measured in both real-time impedance sensing and fluorescence count. In addition, microscopic examination of cell junction proteins showed that CD31/PECAM-1 were more adherent and attached between HUVEC treated with both TNF-α and gelatinase inhibitors comparing to the positive control (TNF-alpha).The mechanisms of action of resveratrol derived lipophenols were assessed. Our findings revealed that resveratrol derived lipophenols have inhibited MMP-9 expression by attenuating the phosphorylation of extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinases (JNK) mitogen-activated protein kinases (MAPK).
24

Participação das Metaloproteinases 2 e 9 no desenvolvimento de aneurisma da aorta abdominal em ratos Wistar / Participation of Metalloproteinases 2 and 9 in Developed of Aortic Abdominal Aneurysms in Wistar Rats.

Mata, Karina Magalhães Alves da 04 September 2008 (has links)
A degradação da matriz extracelular e de proteínas da parede aórtica associada à inflamação é uma das principais características dos aneurismas da aorta abdominal (AAA). O objetivo deste trabalho foi investigar a participação das metaloproteinases 2 e 9 na formação de AAAs, através de um modelo experimental inédito de indução de AAA em ratos Wistar, desencadeado por duas potenciais causas de secreção e ativação de MMP-2 e 9: alteração do fluxo sanguíneo e lesão vascular externa na aorta. A formação de aneurismas foi observada em 60%-70% dos animais, apresentando diâmetro de 7 a 8 vezes maior que o diâmetro normal da aorta. Histologicamente observou-se remodelamento, intensa resposta inflamatória, destruição maciça de fibras elásticas e aumento da síntese de colágeno na parede aórtica. A expressão de ambas as formas de MMP-2 foram observadas tanto nos AAAs como nos grupos controles, neste com menor atividade, entretanto a expressão da pró e da MMP-9 ativa foram encontradas apenas nos AAAs. Conclusão: Nossos resultados sugerem que tanto as MMP-2 quanto as MMP-9 apresentam importante papel no desenvolvimento de AAA e este novo modelo de indução de AAA, pode ajudar a elucidar os mecanismos que desencadeiam a secreção e ativação das MMP-2 e MMP-9 na formação de aneurismas. / Degradation of extracellular matrix and proteins associated with inflammation of the aortic wall is the main characteristics of the abdominal aortic aneurysms (AAA). The aim of this study was investigate the participation of Metalloproteinase 2 and 9 in AAA formation in Wistar rats. A novel experimental model of AAA was developed, providing two potential causes of MMPs secretion and activation, turbulent flow (caused by surgically induced extrinsic stenosis) and outside vascular injury is detailed described. The days analyzed were the 3rd and the 7th post surgery. Aneurysms were observed to occur in 60-70% of the Group AAA, exhibiting a major transversal diameter to 7 from 8 times larger than controls and sham groups. Histologically, the aneurysms wall showed extensive structural remodeling, intense inflammatory response, massive elastic fibers destruction and abundant collagen deposition. Increased pro- and active MMP-2 was demonstrated in the AAA and controls groups, whereas pro- and active MMP-9 were found to be expressed only in the AAA group. Conclusions: MMP-2 and MMP-9 may have a pivotal role in the development of experimental AAA. This model can help to elucidate the mechanisms which trigger off MMP-2 and MMP-9 secretion and activation causing aneurysms.
25

Análise da expressão de MMP-2, MMP-9, MT1-MMP (MMP-14), TIMP-1, TIMP-2, RECK, TGF-Beta e interleucina-8 em câncer de próstata / Expression of MMP-2, MMP-9, MT1-MMP (MMP-14), TIMP-1, TIMP-2, RECK, TGF-Beta e Interleucina-8 genes in the prostate cancer

Reis, Sabrina Thalita dos 02 September 2011 (has links)
Introdução: O câncer de próstata (CaP) é o tumor mais freqüente do homem no Brasil tendo sido estimados mais de 52.350 novos casos em 2010, sendo a segunda causa de óbito por câncer em homens. O prognóstico depende fundamentalmente dos níveis séricos de Prostatic Specific Antigen (PSA) estádio tumoral (TNM) e grau de diferenciação histológica (Gleason). Porém esses têm sido insuficientes na definição do prognóstico da neoplasia. Por isso pesquisas têm sido direcionadas para a identificação de alterações moleculares que possam prever o potencial de agressividade do câncer de próstata. Metaloproteinases da matriz (MMP) são proteínas pertencentes a uma família de aproximadamente 30 enzimas proteolíticas ou endoproteinases que degradam vários componentes da matriz extracelular. A detecção de sua expressão tem sido estudada como marcador sensível e específico de vários tumores, principalmente as MMP pertencentes ao grupo das gelatinases MMP-2 e MMP-9. Objetivo: o objetivo deste nosso trabalho foi avaliarmos pela técnica de qRT-PCR e imuno-histoquímica os níveis de expressão dos genes das MMP pertencentes ao grupo das gelatinases, MMP-2 e MMP-9, bem como outros sabidamente envolvidos em suas vias de ativação (MMP-14, IL-8) e inibição (TIMP-1, TIMP-2, RECK e TGF-) no câncer localizado de próstata. Material e Métodos: O estudo consistiu na análise de espécimes de 79 pacientes com câncer da próstata submetidos a prostatectomia radical entre setembro de 1997 e fevereiro de 2000. Esses oito genes foram então testados quanto a seu valor prognóstico no câncer da próstata através da técnica de reação em cadeia da polimerase quantitativa com transcriptase reversa (qRT-PCR). Análise proteica foi feita a partir de 40 pacientes deste pool. O grupo controle foi composto de tecido de 11 pacientes com hiperplasia benigna da próstata (HPB) tratados cirurgicamente com prostatectomia retropúbica. Resultados: MMP-9 esteve superexpressa e MMP-2, TIMP-1, TIMP-2, MMP 14, IL-8, TGF- e RECK se mostraram subexpressos em tecido representativo de CaP quando comparado com HPB. A análise dos níveis de expressão dos genes com o escore de Gleason, mostrou que MMP-2 e TIMP-2 mesmo mantendo-se subexpressos, tiveram uma expressão maior entre os pacientes que apresentavam Gleason 7 (p=0,04 e p=0,02 respectivamente). De acordo com o valor de PSA préoperatório, encontramos diferenças na expressão de MMP-9. Pacientes que apresentavam um PSA pré-operatório 10 ng/mL possuíam uma mediana de expressão maior que aqueles cujo PSA pré-operatório <10 ng/mL com medianas de expressão de 5,62 e 2,76 respectivamente (p=0,033). Não encontramos diferenças estatísticas entre pacientes que apresentavam ou não recidiva bioquímica quanto a expressão dos 8 genes estudados. Porém o gene da MMP-9 apresentou uma diferença estatística marginal apresentando uma mediana de expressão de 6,29x nos pacientes que apresentaram recidiva bioquímica e de 3,25 nos pacientes que não apresentaram recidiva bioquímica (p=0,090). De acordo com a expressão proteica, encontramos uma maior positividade em MMP-9, MMP-2, TGF-, IL-8 e MMP-14. De acordo com os fatores prognósticos encontramos associação de TIMP-1 com recidiva bioquímica. Conclusão: Encontramos uma superexpressão de MMP-9 e uma subexpressão de MMP-2, TIMP-1, TIMP-2, MMP-14, RECK, IL-8 e TGF- no CaP. Considerando os fatores prognósticos encontramos que aumentados níveis de expressão do gene da MMP-9 associou-se a aumentados níveis de PSA, e mostrou uma tendência de associação com recidiva bioquímica. De acordo com a expressão proteica encontramos que a ausência de TIMP-1 pode ser um indicativo de recidiva bioquímica / Introduction: Currently, Prostate cancer (PCa) is the most common tumor in men in Brazil. It was estimated that more than 52,350 new cases were diagnosed in 2010, being the second cause of death by cancer in man. The prognosis depends mainly on Prostate Specific Antigen (PSA) serum levels, tumor stage (TNM) and histological grade (Gleason), but these parameters, even combined, are insufficient to define the correct prognosis of PCa. Therefore research has been directed towards the identification of molecular alterations that may predict potential aggressiveness of PCa. Matrix metalloproteinases (MMPs) are proteins that belong to a family of about 30 proteolytic enzymes that degrade various components of the extracellular matrix. The analysis of MMPs expression has been studied as a sensitive and specific marker of prognosis of several tumors, and special attention was focused in the group of gelatinases, MMP-2 and MMP-9.Objective: The aim of this study was to evaluate the expression levels of MMP-2 and MMP-9 genes and proteins by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry in localized PCa. We also evaluated the expression of genes that are involved in the control of MMP-2 and MMP as activators (MMP- 14, IL-8) or inhibitors (TIMP-1, TIMP-2, RECK and TGF-).Materials and Methods: The casuistic consisted of 79 surgical specimens from patients with localized PCa who underwent radical prostatectomy between September 1997 and February 2000. The control group was composed of specimens from 11 patients with benign prostatic hyperplasia (BPH) treated surgically with retropubic prostatectomy. The results of the 8 genes expression, through qRTPCR and immunohistochemistry, were correlated to the diagnosis and prognosis of PCa. The protein expression analysis was carried out in 40 patients of the casuistic. Results: The MMP-9 was overexpressed, while MMP-2, TIMP-1, TIMP-2, MMP-14, RECK, IL-8, and TGF- were underexpressed in malignant prostate tissue compared to BPH. Patients with Gleason7 had higher expression of MMP-2 and TIMP-2 (p=0.04, p=0.02 respectively). According to the preoperative PSA value, we found that patients with preoperative PSA10 ng/mL had a median of expression of 5.62 compared to 2.76 when PSA<10 ng/mL (p=0.033). There were no statistical differences between expression of the eight genes and biochemical recurrence during follow up. However, the higher MMP-9 expression was marginally associated with recurrence, the median was of 6.29 in recurrence patients compared to 3.25 in those without recurrence (p=0.090). Regarding the protein expression, we found a higher positivity of MMP-9, MMP-2, TGF-, IL-8 e MMP-14 expression in PCa, and a correlation between the lack of TIMP-1 and tumor recurrence. Conclusion: MMP-9 is overexpressed while MMP-2, TIMP-1, TIMP-2, MMP-14, RECK, TGF- and IL-8 are underexpressed in CaP. According to the prognostic factors, we observed that increased level of MMP-9 was associated with pre-surgical PSA10 ng/mL. Also there was a tendency of association between higher MMP- 9 expression and biochemical recurrence. Overexpression of MMP-9 can be explained by the underexpression of their major inhibitors TIMP-1 and RECK. According to protein expression we found that absence of TIMP-1 is correlated with biochemical recurrence in the PCa
26

Análise quantitativa dos níveis de cálcio, Colagenase A e B durante o reparo ósseo em calvárias de ratos sob o modelo experimental de defeito ósseo / Quantitative analysis of calcium, A and B collagenase levels during the bone repair in rats under calvaria experimental model of bone defect

Lucia, Conrado Ingraci de 28 March 2013 (has links)
O osso é um tipo especializado de tecido com alto teor mineral e desempenha variadas funções no organismo, como a reserva de cálcio, proteção de estruturas vitais e alavanca para a movimentação dos musculos. Constantemente o osso passa por processos de remodelação, o que mantém sua estrutura funcional e repara pequenas fraturas que ocorrem normalmente devido ao estresse do uso contínuo. O sistema de reparo funciona em perfeita sincronia mediante células que produzem os componentes ésseos e células que os reabsorvem permitindo a organização do tecido. Esse sistema de manuteção depende da interação entre estas células bem como dos sinais enviados por mediadores e moduladores. Varias proteínas funcionam como indutores de formação óssea, mas também no sentido de facilitar essa reconstrução. Dentre estas proteínas se encontram as BMPs, que possuem grande potencial osteoindutor, e MMPs, que atuam em diversas fases da construção e manutenção deste tecido. Particularmente a BMP-2 tem mostrado um potencial significativo em termos de indução e sua forma recombinante a rhBMP-2, produzida por engenharia recombinante, foi liberada para comercialização e utilizacao clínica. Quanto às MMPs, há importante função das MMP-2 e MMP-9 neste tecido. A primeira estruturando a matriz e modulando o processo de reabsorção nos processos inflamatórios inerentes ao reparo; a segunda atuando desde fases iniciais às tardias, produzida principalmente por osteoclastos e utilizada na remodelação do osso novo. Porém, esta capacidade de reparo do osso é limitada e defeitos ósseos de grande extensão exigem muito do organismo, podendo levar a um reparo que não se estrutura devidamente. Assim, várias técnicas foram propostas para estimular o desenvolvimento ósseo e a utilizacao de enxertos se mostrou eficaz para fornecer um arcabouço de crescimento, facilitando a implantacao do osso neofomado e protegendo o leito do defeito durante todo o extenso período de recuperação. O presente estudo enfocou três diferentes tipos de enxerto ósseo (autólogo, homólogo e heterólogo) e suas associações com a proteína rhBMP-2, verificando sob o aspecto bioquímico a relação de cada um com a quantidade de MMP-2 e MMP-9 em dois tempos de reparo diferentes. De maneira geral, verificou-se que no primeiro momento há maior produção de MMP-2 e os níveis de MMP-9 se mantém de forma relativamente constante nos dois tempos cirúrgicos. O enxerto autólogo apresenta melhores resultados, seguido dos obtidos no enxerto homólogo e heterólogo respectivamente, entretanto a adição de rhBMP-2 a estes enxertos não parece influenciar nos níveis de MMP-2 e MMP-9 nos dois períodos. A dosagem de cálcio revelou que se apresentavam mais mineralizados os grupos de enxerto autólogo e homólogo, os demais grupos além de apresentar menores niveis de cálcio, ainda decresceram nestes níveis no segundo período do experimento. / Bone is a special tissue with a high mineral content and performs various functions in the body, such as calcium reserves, protection of vital structures and muscles lever during the movement. Bone constantly undergoes remodeling processes, which keeps its functional structure and repair small fractures that commonly occur due to the stress of continuous use. The repair system works perfectly synchronized by the cells that produce bone components and resorbing cells, allowing the perfect tissue organization. This maintenance system depends on the interaction between these cells and the signals sent by mediators and modulators. Several proteins operate to induce bone formation, but also to facilitate the reconstruction. Among these proteins are the BMPs, which have great osteoinductive potential, and MMPs that act at different stages of construction and maintenance of this tissue. Particularly BMP-2 has shown significant potential in terms of induction and its recombinant form, rhBMP-2, produced by recombinant engineering, has been released for clinical use and commercialization. In relation to MMPs, there are important functions of MMP-2 and MMP-9 in this tissue. First, structuring the matrix and modulating the resorption during inflammatory processes inherent to repair; second, acting at early to later stages, produced mainly by osteoclasts and used during bone remodeling. However, this repair capacity is limited and large bone defects require a lot of strength of the body, may leading to a bone repair not well structured. Thus, several proposed techniques to stimulate the development and use of bone grafts were effective to provide a framework for growth, facilitating the implementation of new bone and protecting the defect bed throughout the extended recovery period. This study focused on three different types of bone graft (autologous, homologous and heterologous) and their association with rhBMP-2 protein, evaluating the biochemical aspects according to the amount of MMP-2 and MMP-9 in two different periods of time. In general, it was found that firstly, there is an increased production of MMP-2, and MMP-9 levels remain relatively constant in both considered periods of time. The autologous graft presented the best results followed by homologous and heterologous, respectively; however the addition of rhBMP-2 in these grafts did not seem to influence the MMP-2 and MMP-9 levels, in both periods of time. The calcium dosage revealed more mineralization at the autologous and homologous groups, the other groups, besides having lower calcium levels, decreased these levels at the second period of this experiment.
27

Participação das Metaloproteinases 2 e 9 no desenvolvimento de aneurisma da aorta abdominal em ratos Wistar / Participation of Metalloproteinases 2 and 9 in Developed of Aortic Abdominal Aneurysms in Wistar Rats.

Karina Magalhães Alves da Mata 04 September 2008 (has links)
A degradação da matriz extracelular e de proteínas da parede aórtica associada à inflamação é uma das principais características dos aneurismas da aorta abdominal (AAA). O objetivo deste trabalho foi investigar a participação das metaloproteinases 2 e 9 na formação de AAAs, através de um modelo experimental inédito de indução de AAA em ratos Wistar, desencadeado por duas potenciais causas de secreção e ativação de MMP-2 e 9: alteração do fluxo sanguíneo e lesão vascular externa na aorta. A formação de aneurismas foi observada em 60%-70% dos animais, apresentando diâmetro de 7 a 8 vezes maior que o diâmetro normal da aorta. Histologicamente observou-se remodelamento, intensa resposta inflamatória, destruição maciça de fibras elásticas e aumento da síntese de colágeno na parede aórtica. A expressão de ambas as formas de MMP-2 foram observadas tanto nos AAAs como nos grupos controles, neste com menor atividade, entretanto a expressão da pró e da MMP-9 ativa foram encontradas apenas nos AAAs. Conclusão: Nossos resultados sugerem que tanto as MMP-2 quanto as MMP-9 apresentam importante papel no desenvolvimento de AAA e este novo modelo de indução de AAA, pode ajudar a elucidar os mecanismos que desencadeiam a secreção e ativação das MMP-2 e MMP-9 na formação de aneurismas. / Degradation of extracellular matrix and proteins associated with inflammation of the aortic wall is the main characteristics of the abdominal aortic aneurysms (AAA). The aim of this study was investigate the participation of Metalloproteinase 2 and 9 in AAA formation in Wistar rats. A novel experimental model of AAA was developed, providing two potential causes of MMPs secretion and activation, turbulent flow (caused by surgically induced extrinsic stenosis) and outside vascular injury is detailed described. The days analyzed were the 3rd and the 7th post surgery. Aneurysms were observed to occur in 60-70% of the Group AAA, exhibiting a major transversal diameter to 7 from 8 times larger than controls and sham groups. Histologically, the aneurysms wall showed extensive structural remodeling, intense inflammatory response, massive elastic fibers destruction and abundant collagen deposition. Increased pro- and active MMP-2 was demonstrated in the AAA and controls groups, whereas pro- and active MMP-9 were found to be expressed only in the AAA group. Conclusions: MMP-2 and MMP-9 may have a pivotal role in the development of experimental AAA. This model can help to elucidate the mechanisms which trigger off MMP-2 and MMP-9 secretion and activation causing aneurysms.
28

Modifications chimiques des aptamères, pour des applications en imagerie biomédicale / Chemical modifications of aptamers, for biomedical imagery applications

Hassan, Aref 17 November 2016 (has links)
L’objectif de ma thèse a été de développer de nouvelles sondes utilisables en imagerie biomédicale, basées sur l’utilisation d’aptamères, pour la détection de deux types de tumeurs : les glioblastomes et les mélanomes. Les traceurs développés ont pour objectif de cibler la protéine matricielle hMMP-9. Lors d’une thèse précédente, un aptamère anti hMMP-9 noté F3B a été obtenu. Afin de transformer cet aptamère en une sonde pour l’imagerie biomédicale, différents conjugués F3B ont été préparés: Cy5, DOTA ou MAG3. L’affinité des nouveaux conjugués pour l’hMMP-9 a été évaluée par SPR et sur coupes de tumeurs. Des études de biodistribution des conjugués F3B-DOTA et F3B-MAG3 ont été réalisées sur des souris portant le mélanome, les résultats ont montré que les deux aptamères marqués détectent spécifiquement l’hMMP-9. De plus, la détection de la protéine hMMP-9 par le conjugué F3B-CY5 a été confirmée par imagerie de fluorescence. Afin d’améliorer la sensibilité de détection des tumeurs, deux types de modifications ont été envisagées, développer des structures multimériques de F3B et élaborer d’un système bi-fonctionnel. Pour ces deux approches, nous avons synthétisé un dendrimère à point focal, pouvant donner accès à une imagerie multi-modale. Ce dendrimère porte deux ou trois bras espaceur porteurs d’un groupement azoture utilisé pour le couplage avec les aptamères par la chimie «click». Le dendrimère porte au point focal une fonction amine NH2 utilisée pour fixer une biotine, afin de déterminer l'affinité Kd de cette nouvelle sonde par SPR. Par la suite un ligand DOTA sera fixé afin de pouvoir visualiser ce traceur en TEMP. / The aim of my thesis was to develop new probes that can be used in biomedical imaging, based on the use of aptamers for the detection of two types of tumors: glioblastomas and melanomas. Tracers have been developed with the aim to target the matrix protein hMMP-9. In a thesis, an aptamer anti-hMMP-9 noted F3B was obtained. Based on this compound, different derivatives were prepared for using in biomedical imaging: F3B-Cy5, F3B-DOTA or F3B-MAG3. The affinity of the new conjugates for hMMP-9 was evaluated by SPR and on sections of human melanomas. Biodistribution studies of F3B-DOTA conjugates and F3B-MAG3 were performed at on melanoma bearing mice, the results showed that both radiolabeled aptamers specifically detected the hMMP-9. In addition, optical fluorescence imaging confirmed the binding to hMMP-9 by F3B-CY5. In order to improve tumor detection sensitivity, two types of modifications were investigated: developing of F3B multimeric structures and a bi-functional system. For both these approaches, we synthesized a dendrimer with a focal point, which could give access to a multi-modal imaging. This dendrimer has two or three spacers bearing an azide group used for coupling with aptamers by "click" chemistry. The dendrimer carrying at the focal point an amine function NH2 used for fixing biotin in order to determine the affinity Kd of this new probe by using SPR. A DOTA ligand will be fixed later in order to view this tracer in SPECT.
29

Análise quantitativa dos níveis de cálcio, Colagenase A e B durante o reparo ósseo em calvárias de ratos sob o modelo experimental de defeito ósseo / Quantitative analysis of calcium, A and B collagenase levels during the bone repair in rats under calvaria experimental model of bone defect

Conrado Ingraci de Lucia 28 March 2013 (has links)
O osso é um tipo especializado de tecido com alto teor mineral e desempenha variadas funções no organismo, como a reserva de cálcio, proteção de estruturas vitais e alavanca para a movimentação dos musculos. Constantemente o osso passa por processos de remodelação, o que mantém sua estrutura funcional e repara pequenas fraturas que ocorrem normalmente devido ao estresse do uso contínuo. O sistema de reparo funciona em perfeita sincronia mediante células que produzem os componentes ésseos e células que os reabsorvem permitindo a organização do tecido. Esse sistema de manuteção depende da interação entre estas células bem como dos sinais enviados por mediadores e moduladores. Varias proteínas funcionam como indutores de formação óssea, mas também no sentido de facilitar essa reconstrução. Dentre estas proteínas se encontram as BMPs, que possuem grande potencial osteoindutor, e MMPs, que atuam em diversas fases da construção e manutenção deste tecido. Particularmente a BMP-2 tem mostrado um potencial significativo em termos de indução e sua forma recombinante a rhBMP-2, produzida por engenharia recombinante, foi liberada para comercialização e utilizacao clínica. Quanto às MMPs, há importante função das MMP-2 e MMP-9 neste tecido. A primeira estruturando a matriz e modulando o processo de reabsorção nos processos inflamatórios inerentes ao reparo; a segunda atuando desde fases iniciais às tardias, produzida principalmente por osteoclastos e utilizada na remodelação do osso novo. Porém, esta capacidade de reparo do osso é limitada e defeitos ósseos de grande extensão exigem muito do organismo, podendo levar a um reparo que não se estrutura devidamente. Assim, várias técnicas foram propostas para estimular o desenvolvimento ósseo e a utilizacao de enxertos se mostrou eficaz para fornecer um arcabouço de crescimento, facilitando a implantacao do osso neofomado e protegendo o leito do defeito durante todo o extenso período de recuperação. O presente estudo enfocou três diferentes tipos de enxerto ósseo (autólogo, homólogo e heterólogo) e suas associações com a proteína rhBMP-2, verificando sob o aspecto bioquímico a relação de cada um com a quantidade de MMP-2 e MMP-9 em dois tempos de reparo diferentes. De maneira geral, verificou-se que no primeiro momento há maior produção de MMP-2 e os níveis de MMP-9 se mantém de forma relativamente constante nos dois tempos cirúrgicos. O enxerto autólogo apresenta melhores resultados, seguido dos obtidos no enxerto homólogo e heterólogo respectivamente, entretanto a adição de rhBMP-2 a estes enxertos não parece influenciar nos níveis de MMP-2 e MMP-9 nos dois períodos. A dosagem de cálcio revelou que se apresentavam mais mineralizados os grupos de enxerto autólogo e homólogo, os demais grupos além de apresentar menores niveis de cálcio, ainda decresceram nestes níveis no segundo período do experimento. / Bone is a special tissue with a high mineral content and performs various functions in the body, such as calcium reserves, protection of vital structures and muscles lever during the movement. Bone constantly undergoes remodeling processes, which keeps its functional structure and repair small fractures that commonly occur due to the stress of continuous use. The repair system works perfectly synchronized by the cells that produce bone components and resorbing cells, allowing the perfect tissue organization. This maintenance system depends on the interaction between these cells and the signals sent by mediators and modulators. Several proteins operate to induce bone formation, but also to facilitate the reconstruction. Among these proteins are the BMPs, which have great osteoinductive potential, and MMPs that act at different stages of construction and maintenance of this tissue. Particularly BMP-2 has shown significant potential in terms of induction and its recombinant form, rhBMP-2, produced by recombinant engineering, has been released for clinical use and commercialization. In relation to MMPs, there are important functions of MMP-2 and MMP-9 in this tissue. First, structuring the matrix and modulating the resorption during inflammatory processes inherent to repair; second, acting at early to later stages, produced mainly by osteoclasts and used during bone remodeling. However, this repair capacity is limited and large bone defects require a lot of strength of the body, may leading to a bone repair not well structured. Thus, several proposed techniques to stimulate the development and use of bone grafts were effective to provide a framework for growth, facilitating the implementation of new bone and protecting the defect bed throughout the extended recovery period. This study focused on three different types of bone graft (autologous, homologous and heterologous) and their association with rhBMP-2 protein, evaluating the biochemical aspects according to the amount of MMP-2 and MMP-9 in two different periods of time. In general, it was found that firstly, there is an increased production of MMP-2, and MMP-9 levels remain relatively constant in both considered periods of time. The autologous graft presented the best results followed by homologous and heterologous, respectively; however the addition of rhBMP-2 in these grafts did not seem to influence the MMP-2 and MMP-9 levels, in both periods of time. The calcium dosage revealed more mineralization at the autologous and homologous groups, the other groups, besides having lower calcium levels, decreased these levels at the second period of this experiment.
30

Análise da expressão de MMP-2, MMP-9, MT1-MMP (MMP-14), TIMP-1, TIMP-2, RECK, TGF-Beta e interleucina-8 em câncer de próstata / Expression of MMP-2, MMP-9, MT1-MMP (MMP-14), TIMP-1, TIMP-2, RECK, TGF-Beta e Interleucina-8 genes in the prostate cancer

Sabrina Thalita dos Reis 02 September 2011 (has links)
Introdução: O câncer de próstata (CaP) é o tumor mais freqüente do homem no Brasil tendo sido estimados mais de 52.350 novos casos em 2010, sendo a segunda causa de óbito por câncer em homens. O prognóstico depende fundamentalmente dos níveis séricos de Prostatic Specific Antigen (PSA) estádio tumoral (TNM) e grau de diferenciação histológica (Gleason). Porém esses têm sido insuficientes na definição do prognóstico da neoplasia. Por isso pesquisas têm sido direcionadas para a identificação de alterações moleculares que possam prever o potencial de agressividade do câncer de próstata. Metaloproteinases da matriz (MMP) são proteínas pertencentes a uma família de aproximadamente 30 enzimas proteolíticas ou endoproteinases que degradam vários componentes da matriz extracelular. A detecção de sua expressão tem sido estudada como marcador sensível e específico de vários tumores, principalmente as MMP pertencentes ao grupo das gelatinases MMP-2 e MMP-9. Objetivo: o objetivo deste nosso trabalho foi avaliarmos pela técnica de qRT-PCR e imuno-histoquímica os níveis de expressão dos genes das MMP pertencentes ao grupo das gelatinases, MMP-2 e MMP-9, bem como outros sabidamente envolvidos em suas vias de ativação (MMP-14, IL-8) e inibição (TIMP-1, TIMP-2, RECK e TGF-) no câncer localizado de próstata. Material e Métodos: O estudo consistiu na análise de espécimes de 79 pacientes com câncer da próstata submetidos a prostatectomia radical entre setembro de 1997 e fevereiro de 2000. Esses oito genes foram então testados quanto a seu valor prognóstico no câncer da próstata através da técnica de reação em cadeia da polimerase quantitativa com transcriptase reversa (qRT-PCR). Análise proteica foi feita a partir de 40 pacientes deste pool. O grupo controle foi composto de tecido de 11 pacientes com hiperplasia benigna da próstata (HPB) tratados cirurgicamente com prostatectomia retropúbica. Resultados: MMP-9 esteve superexpressa e MMP-2, TIMP-1, TIMP-2, MMP 14, IL-8, TGF- e RECK se mostraram subexpressos em tecido representativo de CaP quando comparado com HPB. A análise dos níveis de expressão dos genes com o escore de Gleason, mostrou que MMP-2 e TIMP-2 mesmo mantendo-se subexpressos, tiveram uma expressão maior entre os pacientes que apresentavam Gleason 7 (p=0,04 e p=0,02 respectivamente). De acordo com o valor de PSA préoperatório, encontramos diferenças na expressão de MMP-9. Pacientes que apresentavam um PSA pré-operatório 10 ng/mL possuíam uma mediana de expressão maior que aqueles cujo PSA pré-operatório <10 ng/mL com medianas de expressão de 5,62 e 2,76 respectivamente (p=0,033). Não encontramos diferenças estatísticas entre pacientes que apresentavam ou não recidiva bioquímica quanto a expressão dos 8 genes estudados. Porém o gene da MMP-9 apresentou uma diferença estatística marginal apresentando uma mediana de expressão de 6,29x nos pacientes que apresentaram recidiva bioquímica e de 3,25 nos pacientes que não apresentaram recidiva bioquímica (p=0,090). De acordo com a expressão proteica, encontramos uma maior positividade em MMP-9, MMP-2, TGF-, IL-8 e MMP-14. De acordo com os fatores prognósticos encontramos associação de TIMP-1 com recidiva bioquímica. Conclusão: Encontramos uma superexpressão de MMP-9 e uma subexpressão de MMP-2, TIMP-1, TIMP-2, MMP-14, RECK, IL-8 e TGF- no CaP. Considerando os fatores prognósticos encontramos que aumentados níveis de expressão do gene da MMP-9 associou-se a aumentados níveis de PSA, e mostrou uma tendência de associação com recidiva bioquímica. De acordo com a expressão proteica encontramos que a ausência de TIMP-1 pode ser um indicativo de recidiva bioquímica / Introduction: Currently, Prostate cancer (PCa) is the most common tumor in men in Brazil. It was estimated that more than 52,350 new cases were diagnosed in 2010, being the second cause of death by cancer in man. The prognosis depends mainly on Prostate Specific Antigen (PSA) serum levels, tumor stage (TNM) and histological grade (Gleason), but these parameters, even combined, are insufficient to define the correct prognosis of PCa. Therefore research has been directed towards the identification of molecular alterations that may predict potential aggressiveness of PCa. Matrix metalloproteinases (MMPs) are proteins that belong to a family of about 30 proteolytic enzymes that degrade various components of the extracellular matrix. The analysis of MMPs expression has been studied as a sensitive and specific marker of prognosis of several tumors, and special attention was focused in the group of gelatinases, MMP-2 and MMP-9.Objective: The aim of this study was to evaluate the expression levels of MMP-2 and MMP-9 genes and proteins by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry in localized PCa. We also evaluated the expression of genes that are involved in the control of MMP-2 and MMP as activators (MMP- 14, IL-8) or inhibitors (TIMP-1, TIMP-2, RECK and TGF-).Materials and Methods: The casuistic consisted of 79 surgical specimens from patients with localized PCa who underwent radical prostatectomy between September 1997 and February 2000. The control group was composed of specimens from 11 patients with benign prostatic hyperplasia (BPH) treated surgically with retropubic prostatectomy. The results of the 8 genes expression, through qRTPCR and immunohistochemistry, were correlated to the diagnosis and prognosis of PCa. The protein expression analysis was carried out in 40 patients of the casuistic. Results: The MMP-9 was overexpressed, while MMP-2, TIMP-1, TIMP-2, MMP-14, RECK, IL-8, and TGF- were underexpressed in malignant prostate tissue compared to BPH. Patients with Gleason7 had higher expression of MMP-2 and TIMP-2 (p=0.04, p=0.02 respectively). According to the preoperative PSA value, we found that patients with preoperative PSA10 ng/mL had a median of expression of 5.62 compared to 2.76 when PSA<10 ng/mL (p=0.033). There were no statistical differences between expression of the eight genes and biochemical recurrence during follow up. However, the higher MMP-9 expression was marginally associated with recurrence, the median was of 6.29 in recurrence patients compared to 3.25 in those without recurrence (p=0.090). Regarding the protein expression, we found a higher positivity of MMP-9, MMP-2, TGF-, IL-8 e MMP-14 expression in PCa, and a correlation between the lack of TIMP-1 and tumor recurrence. Conclusion: MMP-9 is overexpressed while MMP-2, TIMP-1, TIMP-2, MMP-14, RECK, TGF- and IL-8 are underexpressed in CaP. According to the prognostic factors, we observed that increased level of MMP-9 was associated with pre-surgical PSA10 ng/mL. Also there was a tendency of association between higher MMP- 9 expression and biochemical recurrence. Overexpression of MMP-9 can be explained by the underexpression of their major inhibitors TIMP-1 and RECK. According to protein expression we found that absence of TIMP-1 is correlated with biochemical recurrence in the PCa

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