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Etude structure/fonction du demi-transporteur ABCD2 dans le contexte de l'Adrénoleucodystrophie liée à l'X / Structure/function study of the ABCD2 half-transporter in the context of X-linked AdrenoleukodystrophyGeillon, Flore 30 August 2013 (has links)
L’Adrénoleucodystrophie liée à l’X est une maladie neurodégénérative rare due à des mutations dans le gène ABCD1. Ce gène code un demi-transporteur ABC peroxysomal, impliqué dans l’importation d’acides gras à très longue chaîne. Deux autres demi-transporteurs sont localisés dans la membrane peroxysomale : ABCD2 et ABCD3. La surexpression d’ABCD2 permet de compenser la déficience en ABCD1, ouvrant ainsi des perspectives thérapeutiques. Dans cette optique, l’objectif principal de ma thèse était d’étudier la fonction et la structure d’ABCD2, et plus largement des transporteurs ABC peroxysomaux.Les demi-transporteurs doivent au minimum se dimériser pour constituer un transporteur fonctionnel. Leur dimérisation alternative pourrait moduler leur spécificité de substrat. Afin de tester cette hypothèse, nous avons réalisé des constructions plasmidiques codant différents dimères chimériques, dont la fonctionnalité a été vérifiée par transfection transitoire dans deux modèles cellulaires (fibroblastes humains et levures). D’après nos résultats, ABCD1 et ABCD2 seraient fonctionnels quel que soit leur agencement dimérique. De plus, comme d’autres transporteurs ABC, les transporteurs ABC peroxysomaux pourraient s’oligomériser. En utilisant différentes techniques biochimiques (co-immunoprécipitation, sédimentation sur gradient de sucrose et électrophorèse en conditions natives), sur un modèle cellulaire surexprimant ABCD2-EGFP, nous démontrons qu’ABCD2-EGFP interagit avec ABCD1 et ABCD3, et que les transporteurs ABC peroxysomaux sont capables de s’oligomériser. Il reste désormais à déterminer les facteurs qui contrôlent cette oligomérisation et comprendre la valeur fonctionnelle de ces interactions. / X-linked Adrenoleukodystrophy (X-ALD) is a rare neurodegenerative disease caused by deficiency of the peroxisomal half-transporter ABCD1, implicated in very long chain fatty acids import. Two additional half-transporters are located in the peroxisomal membrane: ABCD2 and ABCD3. Over-expression of ABCD2 is known to compensate for ABCD1 deficiency, making ABCD2 a therapeutic target for X-ALD treatment. In this context, the main objective of my thesis was to investigate the function and the structure of ABCD2, and more broadly, of peroxisomal ABC transporters.Half-transporters must at least dimerize to form a functional transporter. Alternative dimerization could modulate substrate specificity. In order to test this hypothesis, we engineered plasmidic constructs encoding chimeric ABCD dimers, whose functionality has been evaluated by transient transfection in two cell models (human fibroblasts and yeasts). Our results show that, ABCD1 and ABCD2 are functional whatever their dimeric organization. Besides, like other ABC transporters, peroxisomal ABC transporters could oligomerize. By using a multi-technical approach (co-immunoprecipitation, velocity sucrose gradient and native polyacrylamide gel electrophoresis experiments) on stably transfected hepatoma cells expressing ABCD2-EGFP, we demonstrate that ABCD2-EGFP interacts with ABCD1 and ABCD3, and that peroxisomal ABC transporters oligomerize. The perspectives will consist in determining which factors control the oligomerization process and understanding the functional value of these interactions.
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Defining the Importance of Fatty Acid Metabolism in Maintaining Adipocyte Function: A DissertationChristianson, Jennifer L. 27 April 2009 (has links)
Although once considered a simple energy storage depot, the adipose tissue is now known to be a powerful regulator of whole body insulin sensitivity and energy metabolism. This metabolically dynamic organ functions to safely store excess fatty acid as triglyceride, thereby preventing lipotoxicity in peripheral tissues and the development of insulin resistance. In addition, the adipose tissue acts as an endocrine organ and secretes factors, called adipokines, which influence whole body insulin sensitivity and glucose homeostasis. Therefore, understanding adipose tissue development and biology is essential to understanding whole body energy metabolism.
A master regulator of adipose tissue development and whole body insulin sensitivity is the nuclear receptor, PPARγ. Due to the importance of this nuclear receptor in maintaining adipocyte function, disruptions in PPARγ activity result in severe metabolic abnormalities, such as insulin resistance and type 2 diabetes. Conversely, PPARγ activation by synthetic agonists ameliorates these conditions, demonstrating the potent control this nuclear receptor has on whole body metabolism. Therefore, understanding how PPARγ expression and activity are regulated, particularly in the adipose tissue, is paramount to understanding the pathogenesis of type 2 diabetes.
While there are several synthetic PPARγ agonists available, identifying the endogenous ligand or ligands is still an area of intense investigation. Since fatty acids can induce PPARγ activation, in the first part of this thesis, I screened several fatty acid metabolizing enzymes present in the adipocyte to identify novel modulators of PPARγ activity. These studies revealed that the fatty acid Δ9 desaturase, Stearoyl CoA Desaturase 2 (SCD2), is absolutely required for 3T3-L1 adipogenesis and to maintain adipocyte-specific gene expression in fully differentiated cells. Although SCD2 does not appear to regulate PPARγ ligand production, it does potently regulate PPARγ activity by maintaining the synthesis of PPARγ protein. Surprisingly, this effect was found only with SCD2 and not with the highly homologous protein, SCD1. Therefore, these findings identify separate cellular functions for these SCD isoforms and reveal a novel and essential role for fatty acid desaturation in the adipocyte.
Equally important to understanding PPARγ regulation is identifying the downstream mechanisms by which PPARγ activation improves insulin sensitivity. Evidence suggests that the PPARγ target gene, Cidea, is involved in mediating insulin sensitivity by binding to lipid droplets and promoting lipid storage in the adipocyte. Therefore, the second part of thesis provides mechanistic detail into Cidea function by showing that the carboxy terminal 104 amino acids is necessary and sufficient for lipid droplet targeting and the stimulation of triglyceride storage. However, these studies also identified a novel function for Cidea, which requires both the carboxy and amino termini: to induce larger and fewer droplets from smaller dispersed droplets, indicating the possible fusion of droplets. Perhaps this striking change in lipid droplet morphology allows tighter packing and more efficient storage of triglyceride and identifies a novel role for Cidea in lipid metabolism.
The results presented in this thesis elucidate key aspects of lipid metabolism that maintain adipocyte function: SCD2 is required to maintain PPARγ protein expression in the mouse; Cidea is a downstream effector of PPARγ activity by promoting efficient triglyceride storage. Therefore, these findings enhance our understanding of adipocyte biology.
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Synthesis of Novel Small Molecule PPARδ Agonists for Controlling Mesenchymal Stem Cell OsteogenesisKress, Brian J. 05 September 2019 (has links)
No description available.
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The Effect of All-Trans Retinoic Acid and Fatty Acids on MCF-7 Breast Cancer Cell ProgressionBrown, David A 01 October 2009 (has links) (PDF)
Vitamin A metabolites and retinoids may slow the progression of breast cancer and elicit anti-neoplastic properties similar to those of omega-3 fatty acids. Studies using animal models show a decrease in the incidence, growth and metastisis of mammary tumors in the presence of specific fatty acids. This effect is also seen with use of retinoids, specifically all-trans retinoic acid (AtRA). Thus, fatty acids may also alter retinoid homeostasis in mammary carcinoma cells (MCF-7s). The potential for inter/co dependency among fatty acids and retinoids is considerable, and here it has been hypothesized that a decrease in cancer progression will occur in the presence of both compounds. MCF-7’s were seeded in a 48 well plate at 5,000 cells per well. After 24 hr, cells were treated with either 1 µM AtRA alone, fatty acids alone, or AtRA + fatty acids. Fatty acid treatments (Linoleic, and Linolenic) were administered at 2.5 uM concentrations. Each fatty acid treatment was also combined with 1 µM AtRA to determine if there is a synergistic effect on slowing cell growth. Both culture media and treatments were changed at 24 hour intervals over a 3 day trial. When compared to the controls, cells treated with 1 µM AtRA or 2.5 µM Linolenic acid both inhibited cell growth. Interestingly, when combined with Linolenic acid, AtRA treatment resulted in a significant (nearly 50%) additional growth inhibition when compared to treatment with AtRA alone. Our results suggest that AtRA and Linolenic acid have a inter/co dependency that significantly inhibits breast cancer cell growth in vitro by 73.4 % compared to control, and 49.7% compared to AtRA alone over 72 hours. We conclude that AtRA and linolenic acid have a combined effect in breast cancer cell proliferation in-vitro and their role in dietary prevention warrants further investigation.
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Dissecting Trypanosome Metabolism by Discovering Glycolytic Inhibitors, Drug Targets, and Glycosomal pH RegulationCall, Daniel Hale 07 May 2024 (has links) (PDF)
Trypanosoma brucei, the causative agent of African trypanosomiasis, and its relatives Trypanosoma cruzi and several Leishmania species belong to a class of protozoa called kinetoplastids that cause a significant health burden in tropical and semitropical countries across the world. While an improved therapy was recently approved for African trypanosomiasis, the therapies available to treat infections caused by T. cruzi and Leishmania spp. remain relatively poor. Improving our understanding of T. brucei metabolism can inform on metabolism of its relatives. The purpose of the research presented in this dissertation was to develop novel tools and methods to study metabolism in T. brucei with the ultimate aim to improve treatments of all kinetoplastid diseases. We developed a novel tool to study glycosomal pH in the bloodstream form of T. brucei. Using this tool, we discovered that this life stage regulates glycosomal pH differently than the procyclic form, or insect-dwelling stage, and only uses sodium/proton transporters to regulate glycosomal pH. I pioneered a thermal proteome profiling method in this parasite to discover drug targets and their effects on cell pathways. Using this method, I found that other proteins may be involved in glycosomal pH regulation, including PEX11 and a vacuolar ATPase. This method also illuminated several important pathways influenced by glycosomal pH regulation, including glycosome proliferation, vesicle trafficking, protein glycosylation, and amino acid transport. Metabolic studies in kinetoplastid parasites are currently hampered by the lack of available chemical probes. We developed a novel flow cytometry-based high-throughput drug screening assay to discover chemical probes of T. brucei glycolysis. This method combines the advantages of phenotypic (or cell-based) screens with the advantage of targeted (purified protein) screens by multiplexing biosensors that measure multiple glycolytic metabolites simultaneously, such as glucose, ATP, and glycosomal pH. The complementary information gained is then used to distinguish the part of glycolysis identified inhibitors target. We validated the method using the well characterized glycolytic and alternative oxidase inhibitors 2-deoxyglucose and salicylhydroxamic acid respectively. We demonstrated the screening assay with a pilot screen of 14,976 compounds with decent hit rates for each sensor (0.2-0.4%). About 64% of rescreened hits repeated activity in at least one sensor. We demonstrated one compound with micromolar activity against two biosensors. In summary, we developed and demonstrated a novel screening method that can discover glycolytic chemical probes to better study metabolism in this and related parasites. There are few methods to study enzyme kinetics in the live-cell environment. I developed a kinetic flow cytometry assay that can measure enzyme and transporter activity using fluorescent biosensors. I demonstrated this by measuring glucose transport kinetics and alternative oxidase inhibition kinetics, with the measured kinetic parameters similar to those previously reported. We plan to expand on this method to measure transport kinetics in the glycosome and other organelles which has not been done before. We previously performed a drug screen to identify inhibitors that decrease intracellular glucose in T. brucei. I have performed preliminary work identifying the glucose transporter THT1 as one of the targets of optimized glucose inhibitors using the previously mentioned thermal proteome profiling method. We expect this finding will improve our ability to move these compounds from hit to lead in the drug discovery pipeline. Together, I have developed several flow cytometry and proteomics methods to better study metabolism in T. brucei. These tools are beginning to be used in related parasites. We expect the discoveries made using these tools will improve our ability to treat these neglected tropical diseases.
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Régulation de l'expression hépatique de récepteur LSR (lipolys stimulated lipoprotein receptor) : rôles de l'acide docosahexaénoïque et du récepteur PPARa ( peroxisome proliferator-activated receptor alpha) / Regulation of the expression of hepatic lipolysis stimulated lipoprotein receptor : roles of docosahexaenoic acid and peroxisome proliferator-activated receptor alphaAkbar, Samina 11 December 2013 (has links)
Le récepteur LSR est un acteur important du métabolisme hépatique, puisqu'il joue un rôle dans la clairance des lipoprotéines à ApoB/ApoE riches en triglycérides durant la période postprandiale. Dans cette étude, nous avons montré qu'un traitement in vitro par DHA peut augmenter les niveaux de protéine et d'activité LSR dans les cellules d'hépatome de souris Hepa 1-6. En toute cohérence, un régime supplémenté en DHA a conduit à élever les niveaux de protéine LSR hépatique chez la souris. Mais aucune de ces deux études n'a montré de changement au niveau des ARNm. Ceci suggère que l'enrichissement en DHA influe positivement sur le microenvironnement de LSR et son ancrage à la surface de la cellule. Nous avons ensuite étudié le rôle du récepteur PPAR[alpha] dans la régulation du gène lsr. Une analyse in silico nous a permis d'identifier des éléments PPRE dans la région 5' régulatrice du gène humain et de ses homologues de souris et de rat. Des traitements pharmacologiques par des agoniste et antagoniste spécifiques de PPAR[alpha] ont montré que ce récepteur est impliqué dans la régulation transcriptionnelle de l'expression du LSR dans les cellules Hepa 1 6. Enfin, une analyse transcriptomique a révélé une diminution de l'expression de PPAR[alpha] et d'autres gènes impliqués dans le métabolisme lipidique hépatique chez la souris LSR+/- sous régime standard ou riche en graisses. En conclusion, toutes ces études indiquent que l'activité LSR hépatique est sous le contrôle de facteurs nutritionnels capables d'activer divers mécanismes de régulation, faisant du LSR une cible d'intérêt potentiel pour des stratégies nutritionnelles ou thérapeutiques destinées à prévenir ou traiter les dyslipidémies / Lipolysis stimulated lipoprotein receptor (LSR) plays an important role in the clearance of ApoB/ApoE containing triglyceride-rich lipoproteins during postprandial phase. In this study, we demonstrated that in vitro treatment of mouse hepatoma cells, Hepa 1-6, with docosahexaenoic acid (DHA) led to an increase in LSR protein levels as well as its activity. Furthermore, the mice placed on the diet supplemented with DHA showed an increase in hepatic LSR protein. However, the mRNA levels remained unchanged in both in vitro and in vivo studies, suggesting that DHA enrichment may result in changes in LSR microenvironment that could affect its anchorage at the surface of cell membrane. Specific peroxisome proliferator response elements were identified in the upstream region of human, mouse and rat lsr gene by in silico analysis. We therefore sought to determine the role of the transcription factor, peroxisome proliferator-activated receptor (PPAR[alpha]), in LSR regulation. In vitro pharmacological studies using PPAR[alpha]-selective agonist and antagonist agents demonstrated that PPAR[alpha] is indeed involved in the transcriptional regulation of LSR expression. Furthermore, qPCR array analysis revealed the downregulation of PPAR[alpha] and various genes involved in hepatic lipid metabolism in LSR+/- mice on standard and high-fat diets. In conclusion, these studies show that the hepatic LSR activity is controlled by dietary factors that can activate various pathways involved in regulating lipid homeostasis, therefore representing LSR as a potential target for either nutritional or therapeutic strategies towards the prevention or treatment of dyslipidemia
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Agonista PAN-PPAR (receptores ativadores de proliferação peroxissomal) e alterações hepáticas na prole adulta de camundongos de mães obesas / PAN-PPAR agonist and hepatic alterations in adult offspring of obese dams miceD'Angelo Carlo Magliano 26 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo do presente estudo foi avaliar se o Bezafibrato, um agonista PAN-PPAR, é capaz de aliviar a doença não alcoólica do fígado gorduroso (NAFLD) na prole de machos de mães C57BL/6 obesas. Fêmeas virgens foram alimentadas com uma dieta HL (hiperlipídica, 49% de lipídios) ou uma dieta C (controle, 10% de lipídios) por oito semanas antes do acasalamento e durante os períodos de gestação e lactação. A prole de machos foi subdividida em quatro grupos: C (dieta controle para as mães e filhotes); C/BZ (dieta controle para as mães e filhotes com tratamento com Bezafibrato[100mg/Kg]); HL (dieta HL para as mães e dieta controle para os filhotes); e HL/BZ (dieta HL para as mães e dieta controle para os filhotes com tratamento com Bezafibrato [100mg/Kg]). O tratamento com Bezafibrato começou na 12 semana e se manteve por três semanas. Análise do metabolismo, bioquímica, estereológica e por western-blotting foram realizadas. A dieta HL causou um fenótipo de sobrepeso nas mães e acarretou em uma intolerância oral à glicose com aumento da glicemia de jejum. A prole HL apresentou hiperfagia, ganho de massa corporal, altos níveis de triglicerídeo hepático e plasmático, esteatose hepática e aumento da expressão de proteínas lipogênicas concomitante com diminuição do receptor ativador de proliferação peroxissomal alfa (PPARα), que é responsável pela β-oxidação e aumento do receptor ativador de proliferação peroxissomal gama (PPARγ) e do elemento regulador de esterol ligante da proteína 1 (SREBP-1c) proteínas envolvidas na lipogênese hepática. Por outro lado, o tratamento com o Bezafibrato reverteu o quadro da programação metabólica no fígado, com uma melhora dos parâmetros morfológicos, bioquímicos e moleculares do fígado dos animais, com um aumento da ativação de PPARα em associação a uma diminuição do PPARγ e não alterando a expressão de SREBP-1c. Em conclusão, nós demonstramos que o tratamento com Bezafibrato melhora a NAFLD causada pela obesidade materna. / The aim of the present study was to evaluate whether Bezafibrate , a PAN-PPAR agonist, could attenuate non-alcoholic fatty liver disease (NAFLD) of male offspring from obese C57BL/6 dams. Dams were fed on a HF (high-fat, 49% lipids) diet or SC (standard chow; 10% lipids) diet for 8 weeks before mating and during gestation and lactation periods. Male offspring were subdivided into 4 groups: SC (standard-chow for dams and offspring); SC/BZ [standard-chow for dams and offspring with treatment with BZ (100mg/Kg)]; HF (high-fat diet for dams and standard-chow for offspring); HF/BZ [high-fat diet for dams and standard-show for offspring with treatment with Bezafibrate (100mg/Kg)]. Treatment with Bezafibrate started at 12th week and was maintained for 3 weeks. Metabolic measurements, biochemical analysis, stereological tools and western-blotting were performed. The HF diet yielded an overweight phenotype and an increase in oral glucose tolerance and fasting glucose of dams. The HF offspring presented hyperphagia, body mass gain, high levels of plasmatic and hepatic triglycerides, impairment of glucose metabolism, hepatic steatosis and high expression of lipogenic proteins concomitant to decreased expression of PPARα, which is responsible for β-oxidation. On the other hand, treatment with Bezafibrate reverted hepatic outcomes of metabolic programming, with an improvement of morphological, biochemical and molecular parameters of animals livers, with an increase of PPARα activation in association with a decrease of PPARγ expression and no changes in SREBP-1c expression. In conclusion, we demonstrated that treatment with Bezafibrate improved NAFLD caused by maternal obesity.
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Agonista PAN-PPAR (receptores ativadores de proliferação peroxissomal) e alterações hepáticas na prole adulta de camundongos de mães obesas / PAN-PPAR agonist and hepatic alterations in adult offspring of obese dams miceD'Angelo Carlo Magliano 26 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo do presente estudo foi avaliar se o Bezafibrato, um agonista PAN-PPAR, é capaz de aliviar a doença não alcoólica do fígado gorduroso (NAFLD) na prole de machos de mães C57BL/6 obesas. Fêmeas virgens foram alimentadas com uma dieta HL (hiperlipídica, 49% de lipídios) ou uma dieta C (controle, 10% de lipídios) por oito semanas antes do acasalamento e durante os períodos de gestação e lactação. A prole de machos foi subdividida em quatro grupos: C (dieta controle para as mães e filhotes); C/BZ (dieta controle para as mães e filhotes com tratamento com Bezafibrato[100mg/Kg]); HL (dieta HL para as mães e dieta controle para os filhotes); e HL/BZ (dieta HL para as mães e dieta controle para os filhotes com tratamento com Bezafibrato [100mg/Kg]). O tratamento com Bezafibrato começou na 12 semana e se manteve por três semanas. Análise do metabolismo, bioquímica, estereológica e por western-blotting foram realizadas. A dieta HL causou um fenótipo de sobrepeso nas mães e acarretou em uma intolerância oral à glicose com aumento da glicemia de jejum. A prole HL apresentou hiperfagia, ganho de massa corporal, altos níveis de triglicerídeo hepático e plasmático, esteatose hepática e aumento da expressão de proteínas lipogênicas concomitante com diminuição do receptor ativador de proliferação peroxissomal alfa (PPARα), que é responsável pela β-oxidação e aumento do receptor ativador de proliferação peroxissomal gama (PPARγ) e do elemento regulador de esterol ligante da proteína 1 (SREBP-1c) proteínas envolvidas na lipogênese hepática. Por outro lado, o tratamento com o Bezafibrato reverteu o quadro da programação metabólica no fígado, com uma melhora dos parâmetros morfológicos, bioquímicos e moleculares do fígado dos animais, com um aumento da ativação de PPARα em associação a uma diminuição do PPARγ e não alterando a expressão de SREBP-1c. Em conclusão, nós demonstramos que o tratamento com Bezafibrato melhora a NAFLD causada pela obesidade materna. / The aim of the present study was to evaluate whether Bezafibrate , a PAN-PPAR agonist, could attenuate non-alcoholic fatty liver disease (NAFLD) of male offspring from obese C57BL/6 dams. Dams were fed on a HF (high-fat, 49% lipids) diet or SC (standard chow; 10% lipids) diet for 8 weeks before mating and during gestation and lactation periods. Male offspring were subdivided into 4 groups: SC (standard-chow for dams and offspring); SC/BZ [standard-chow for dams and offspring with treatment with BZ (100mg/Kg)]; HF (high-fat diet for dams and standard-chow for offspring); HF/BZ [high-fat diet for dams and standard-show for offspring with treatment with Bezafibrate (100mg/Kg)]. Treatment with Bezafibrate started at 12th week and was maintained for 3 weeks. Metabolic measurements, biochemical analysis, stereological tools and western-blotting were performed. The HF diet yielded an overweight phenotype and an increase in oral glucose tolerance and fasting glucose of dams. The HF offspring presented hyperphagia, body mass gain, high levels of plasmatic and hepatic triglycerides, impairment of glucose metabolism, hepatic steatosis and high expression of lipogenic proteins concomitant to decreased expression of PPARα, which is responsible for β-oxidation. On the other hand, treatment with Bezafibrate reverted hepatic outcomes of metabolic programming, with an improvement of morphological, biochemical and molecular parameters of animals livers, with an increase of PPARα activation in association with a decrease of PPARγ expression and no changes in SREBP-1c expression. In conclusion, we demonstrated that treatment with Bezafibrate improved NAFLD caused by maternal obesity.
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Subcellular and functional analyses of two small heat shock proteins and protein kinases from peroxisomes of Arabidopsis thaliana L. / Subzelluläre und funktionelle Analysen von zwei kleinen Hitzeschockproteinen und Proteinkinasen von Peroxisomen aus Arabidopsis thaliana L.Ma, Changle 19 January 2006 (has links)
No description available.
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Expressão aumentada dos antígenos de MMP-9 PPAR, Chlamydophila pneumoniae e Mycoplasma pneumoniae em fragmentos ateroscleróticos de aorta com aneurisma / Increased expression of MMP-9, PPAR a and Chlamydophila pneumoniae e Mycoplasma pneumoniae antigens in atherosclerostic aortic fragments with aneurysmsRoggerio, Alessandra 12 September 2008 (has links)
Introdução: Aneurisma de aorta é considerado uma doença inflamatória crônica, mas ainda é controverso se está relacionado a aterosclerose aos agentes infecciosos. Antígenos de Chlamydophila pneumoniae (CP) e Mycoplasma pneumoniae (MP) foram encontrados em grande quantidade nas placas instáveis que usualmente estão associadas a remodelamento positivo e inflamação do vaso. Metaloproteinase da matriz 9 (MMP-9) está implicada na fragilidade da parede vascular e na formação dos aneurismas. Os efeitos imunomodulatórios dos receptores ativados por proliferador de peroxissomo (PPARs) têm sido relacionados à aterosclerose. Objetivos: Comparar lesões ateroscleróticas graves com e sem aneurisma do ponto de vista inflamatório e infeccioso, analisando antígenos de MP e CP e expressão de MMP-9, TIMP-1 e PPARs. Métodos: No presente estudo quantificamos, através da técnica de imunoistoquímica, antígenos de MMP- 9, TIMP-1, PPARs a e , e dos agentes infecciosos CP e MP em fragmentos de aorta ateroscleróticos com aneurisma (n=14) e sem aneurisma (n=14). Resultados: A adventícia e o tecido adiposo periadventicial (TAP) dos aneurismas apresentaram intensa inflamação. Expressão de MMP-9 esteve aumentada no TAP e agentes infecciosos, TIMP-1 e PPAR a estiveram aumentados na adventícia e no TAP, sem diferença em relação a expressão de PPAR . Colágeno, TIMP-1 e PPARs estiveram positivamente correlacionados no grupo com aterosclerose, mas não no grupo com aneurisma. Conclusão: Nossos achados sugerem que aneurisma de aorta é uma complicação das lesões ateroscleróticas. Quantidade aumentada de Chlamydophila pneumoniae e Mycoplasma pneumoniae na adventícia e PAT sem correlação da resposta de TIMP-1 e PPARs são achados que estão associados com a presença de aneurisma nos segmentos de aorta ateroscleróticos / Introduction: Aortic aneurysm is considered a chronic inflammatory disease, but remains a controversial matter if it is related to atherosclerosis and infectious agents. Chlamydophila pneumoniae (CP) and Mycoplasma pneumoniae (MP) antigens were found in higher amount in unstable plaques that are usually associated to positive remodeling and vessel inflammation. Matrix metalloproteinase 9 (MMP-9) has been implicated in vascular wall fragility and aneurysm development. The immunemodulator effects of peroxisome proliferators - activated receptor (PPARs) have been related to atherosclerosis. Objectives: To compare severe atherosclerotic lesions with and without aneurysms by inflammatory and infectious point of view, analyzing MP and CP, MMP-9, TIMP-1 and PPARs antigens. Methods: In the present study we quantified, using immunohistochemistry technique, MMP-9, TIMP-1, PPAR a and and infectious agents CP and MP antigens in aortic atherosclerotic fragments with aneurysms. (n=14) and without aneurysms (n=14). Results: Adventitia and periadventitial adipose tissue (PAT) from aneurysms showed intense inflammation. MMP-9 expression has increased in PAT and the infectious agents, TIMP-1 and PPAR a were increased in adventitia and PAT in aneurysmatic group, without difference related to PPAR expression. Collagen, TIMP-1 and PPARs were positively correlated in atherosclerotic group, but it was not observed in aneurysmatic group. Conclusion: Our data have suggested that aortic aneurysm is a complication of aortic atherosclerotic lesions. Increased amount of Chlamydophila pneumoniae and Mycoplasma pneumoniae in the adventitia and PAT without a correlated TIMP-1 and PPARs response are findings that were associated with the presence of aneurysm in atherosclerotic aortic segments
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