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Les voies de signalisation utérines à l'émergence de la diapause embryonnaire chez le vison américainLefèvre, Pavine L.C. 08 1900 (has links)
La diapause embryonnaire se manifeste par un arrêt réversible du développement embryonnaire durant la période de préimplantation et induit un retard de l’implantation. Chez le vison américain, une diapause embryonnaire obligatoire caractérise chaque gestation. Si les mécanismes de contrôle de la diapause embryonnaire obligatoire chez cette espèce sont bien connus, le rôle utérin impliqué dans la réactivation de l’embryon demeure, quant à lui, encore inconnu.
Le sujet de ce doctorat a consisté dans un premier temps à explorer l’environnement utérin à la sortie de la diapause embryonnaire afin de caractériser, dans un deuxième temps, les principaux acteurs utérins qui provoquent la réactivation de l’embryon.
Nous avons effectué une analyse du transcriptome utérin à l’émergence de la diapause embryonnaire ce qui a permis de construire une librairie de 123 séquences d’ADNc utérines différentiellement exprimées à la réactivation de l’embryon et homologues à des séquences de gènes connues chez d’autres espèces. Ces gènes sont impliqués dans la régulation du métabolisme (25 %), de l’expression génique (21 %), de la transduction de signal (15 %), du cycle cellulaire (15 %), du transport (10 %) et de la structure cellulaire (9 %), reflétant ainsi d’importantes modifications utérines à la réactivation embryonnaire. Nous avons validé l’expression différentielle de dix gènes ainsi identifiés : GDF3 (growth and differentiation 3), ALCAM (activated leukocyte cell adhesion molecule), ADIPOR1 (adiponectin receptor 1), HMGN1 (high mobility group N1), TXNL1 (thioredoxin like 1), TGM2 (tissue transglutaminase 2), SPARC (secreted protein acidic rich in cystein), et trois gènes codant pour AZIN1 (antizyme inhibitor 1), ODC1 (ornithine decarboxylase 1) et SAT1 (spermidine/spermine N1-acetyltransferase), des enzymes impliquées dans la biosynthèse des polyamines. Le patron de l’expression spatio-temporel de SPARC et d’HMGN1 illustrent spécifiquement un remodelage tissulaire et de la chromatine au niveau utérin à la sortie de la diapause embryonnaire.
Ayant mesuré une augmentation des concentrations utérines en polyamines à la reprise du développement embryonnaire, nous avons émis l’hypothèse que les polyamines seraient impliquées dans les événements menant à la sortie de la diapause. L’inhibition de la biosynthèse des polyamines par un traitement à l’ α-difluoromethylornithine (DFMO) a provoqué une diminution significative de la proliferation cellulaire dans les embryons à la réactivation, un retard du moment de l’implantation, mais n’a pas affecté le succès de la reproduction. De manière similaire, nous avons induit un état de dormance dans les cellules de trophoblaste de vison en présence DFMO dans le milieu de culture, et constaté que cet état était réversible.
En conclusion, cette étude a non seulement ouvert de nouveaux horizons quant à la compréhension du rôle utérin dans les événements menant à la sortie de la diapause embryonnaire, mais a démontré pour la première fois, l’existence de facteurs utérins indispensables à la réactivation de l’embryon: les polyamines. / Embryonic diapause is characterized by a reversible arrest of blastocyst development prior to implantation and delay in implantation. In the American mink, embryonic diapause is a characteristic of each gestation. Although the mechanisms which control obligate embryonic diapause of this species are well known, the role of the uterus involved in blastocyst reactivation remains elusive.
The subject of this doctoral research consisted first in exploring the uterine environment at the emergence of embryonic diapause in order to subsequently determine, the main factors in the uterus that provoke reactivation of the embryo.
We have undertaken an analysis of the uterine transcriptome at the emergence of embryonic diapause which has enabled us to set up a library of 123 cDNA uterine sequences differentially expressed at blastocyst reactivation, and homologue gene sequences known in other species. Twenty-five percent of these genes are implicated in genetic expression, 15 % in cell signal transduction, 15 % in cell cycle, 10 % in transport and 9 % in cell structure. All of them reflect significant uterine modifications at blastocyst reactivation. We have validated differential expression of ten genes, identified as: GDF3 (growth and differentiation 3), ALCAM (activated leukocyte cell adhesion molecule), ADIPOR1 (adiponectin receptor 1), HMGN1 (high mobility group N1), TXNL1 (thioredoxine like 1), TGM2 (tissue transglutaminase 2), SPARC (secreted protein acidic rich in cystein), and three genes encoding for AZIN1 (antizyme inhibitor 1), ODC1 (ornithine decarboxylase 1) and SAT1 (spermidine/spermine N1-acetyltransferase), which are enzymes implicated in polyamine biosynthesis. The spatio-temporal expression patterns of SPARC and HMGN1 illustrate tissue and chromatin remodelling in the uterus at the termination of embryonic diapause.
Having measured an increase in concentration of polyamines in the uterus at the resumption of blastocyst development, we have hypothetized that polyamines are implicated in the emergence of blastocysts from diapause. We inhibited polyamine biosynthesis in pregnant mink females during early blastocyst reactivation. The inhibition of polyamine biosynthesis through treatment with α-difluoromehtylornithine (DFMO) provoked a major reduction in cell proliferation in blastocysts at reactivation and a delay in the timing of implantation, but did not affect the success of reproduction. Similarly, we induced a reversible dormant state in cultured mink trophoblast cells traited with DFMO.
To conclude, not only are results of this study a breakthrough in the understanding of the role of the uterus in stimulating at the emergence of blastocysts from embryonic diapause, but also, for the very first time, they indicate the existence of uterine factors, the polyamines, that are responsible for blastocysts reactivation.
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Estabelecimento de um modelo de gestação complicada por diabetes tipo 1 em camundongos: avaliação do seu impacto sobre o ambiente uterino no início da gestação. / Establishment of a mouse model of pregnancy complicated by type 1 diabetes: evaluation of its impact on the uterine environment at early pregnancy .Ribeiro, Rodolfo Favaro 29 July 2011 (has links)
Por meio desse estudo foi estabelecido um novo modelo de gestação complicada por diabetes tipo 1 em camundongos. O diabetes foi induzido em fêmeas de camundongos Swiss por aloxana e os animais foram acasalados após diferentes períodos de tempo. As fêmeas diabéticas apresentaram hiperglicemia, hipoinsulinemia, glicosúria, polifagia, polidipsia, e diminuição de peso corporal. A histoquímica do Picrosirius demonstrou o aumento dos colágenos fibrilares na decídua do grupo diabético. Análises imunohistoquímicas mostraram aumento dos colágenos I e V e diminuição do colágeno III e dos proteoglicanos biglicam e lumicam. Entretanto, a análise por PCR em tempo real indicou apenas o aumento do mRNA do colágeno I. A microscopia eletrônica revelou alterações na fibrilogênese do colágeno. O miométrio apresentou alterações na organização, citoarquitetura e sistema contráctil das camadas musculares, associadas à diminuição da proliferação celular. Esses resultados contribuem para explicar as alterações no desenvolvimento embrionário e a maior incidência de partos prematuros nas gestações diabéticas. / By means of this study a new mouse model of pregnancy complicated by type 1 diabetes was established. Diabetes was induced in female Swiss mice by alloxan and the animals were mated after different periods of time. Diabetic females showed hyperglycemia, hypoinsulinemia, glycosuria, polyphagy, polydipsy and decreased body weight. Picrosirius histochemistry demonstrated increased fibrillar collagens in the decidua of the diabetic group. Immunohistochemical analysis showed increased collagens I and III, and decreased collagen V and proteoglycans biglycan and lumican. However, real time PCR analysis indicated that only collagen I mRNA was increased. Transmission electron microscopy revealed alterations in collagen fibrillogenesis. The myometrium showed alterations in the organization, cytoarchitecture and contractile system of the muscle layers, associated with decreased proliferation. These results contribute to explain the alterations in embryo development and the higher incidence of preterm labor in diabetic pregnancies.
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Caracterização de proteoglicanos do útero de camundongos durante o ciclo estral e em animais ovarectomizados: análise dos efeitos da castração e da reposição hormonal. / Characterization of proteoglycans in the mouse uterus during the estrous cycle and in ovariectomized animals: analysis of the effects of castration and hormone replacement.Salgado, Renato de Mayrinck 14 August 2009 (has links)
A matriz extracelular (MEC) dos tecidos uterinos é altamente remodelada na gestação de camundongos. Os objetivos deste estudo foram avaliar a influência dos hormônios ovarianos estrógeno (E2) e progesterona (P4) sobre a estrutura dos tecidos uterinos de camundongo e a deposição dos proteoglicanos decorim, biglicam, fibromodulim, lumicam, perlecam e versicam nestes tecidos. Para isto, utilizamos um modelo de castração e reposição hormonal, e o ciclo estral como parâmetro fisiológico. Verificamos que, como na gestação, durante o ciclo estral ocorre intensa remodelação na estrutura e na MEC dos tecidos uterinos. Verificamos ainda que a resposta aos hormônios ovarianos é: compartimento-específica; hormônio-específica e molécula-específica. Notável foi a modulação do versicam pelos hormônios ovarianos. P4 induz a deposição de versicam no estroma, enquanto o miométrio responde apenas a E2. A modulação dos proteoglicanos pelos hormônios ovarianos mostra a relevância destas moléculas para a composição de um ambiente uterino propício para o desenvolvimento do embrião. / The extracellular matrix (ECM) of the mouse uterine tissues is highly remodeled during pregnancy. The aim of this study was to demonstrate the influence of estrogen (E2) and progesterone (P4) on the uterine structure and on the deposition of the proteoglycans decorin, biglycan, fibromodulin, lumican, perlecan and versican in these tissues. For that purpose, we used a model of castration e hormone replacement as main strategy, and the estrous cycle as physiological parameter. We verified that, as in pregnancy, during the estrous cycle an intense remodeling occurs on the structure and the ECM of the uterine tissues. We also showed that the response to the ovarian hormones is: compartment-; hormone- and molecule- specific. Noteworthy was the modulation of versican by the hormones: P4 induces the deposition of versican in the stroma, whereas the myometrium responds only to E2. The modulation of proteoglycans by the ovarian hormones indicates the relevance of these molecules for the composition of a proper microenvironment for embryo development.
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Tratamento das pacientes sintomáticas portadoras de miomas uterinos através da associação das técnicas de embolização dos miomas e ligadura endovascular das artérias uterinas / Uterine artery embolization with polyvinyl-alcohol particles and metallic coils for the treatment of symptomatic patients with fibroidsRicardo Augusto de Paula Pinto 27 March 2007 (has links)
Os miomas uterinos são os tumores benignos mais comuns do trato genital feminino, sendo que nas mulheres portadoras, 30% são sintomáticos e exigem alguma forma de tratamento. No presente estudo, foram tratadas 35 pacientes sintomáticas com diagnóstico clínico e ultra-sonográfico de mioma uterino, por meio da embolização dos miomas com partículas de polivinil-álcool associadas à obstrução das artérias uterinas com micromolas fibradas. A avaliação clínica e ecográfica foram inicialmente feitas e o acompanhamento realizado após um, três, seis e doze meses do procedimento. O sucesso técnico foi de 94,3%. O volume uterino médio era de 404,53 cm3 antes do tratamento endovascular percutâneo e o sintoma mais freqüente, em 82,9%, a menorragia. A redução média dos volumes uterinos foi de 21,4%, 39,7%, 53,8% e 59,8% respectivamente em um, três, seis e 12 meses (p < 0,01). Houve, também, a redução do volume do nódulo miomatoso dominante em 5%, 18,5%, 26,8% e 32,9% em um, três, seis e 12 meses, respectivamente (p < 0,01). A melhora e o controle da menorragia foram obtidos em 100% das pacientes tratadas. Houve necessidade de histerectomia em uma paciente por insucesso no controle da dor após seis meses do procedimento. A embolização dos miomas uterinos com partículas de polivinil-álcool associada à oclusão endovascular das artérias uterinas com micromolas fibradas é uma alternativa de tratamento minimamente invasivo para as pacientes sintomáticas portadoras de miomas uterinos que proporciona controle e melhora dos sintomas e redução do tamanho dos miomas e do volume uterino. / Uterine fibroids are the most frequent benign tumors of the female genital tract. The tumors are symptomatic in about 30% of the cases, requiring medical treatment. In the present study, a total of 35 clinically symptomatic patients with ultrasonographic diagnosis of fibroids underwent endovascular treatment, which consisted of embolization of the uterine arteries with 355-500 micras PVA particles associated to metallic coils. Clinical and ultrasonographic evaluations were performed at baseline, 1, 3, 6 and 12 months post-intervention. Technical success was obtained in 94.3% of the cases. Mean uterine volume before the procedure was 404.53 cm³ and menorrhagia was the most frequent symptom (82.9%). Mean reduction of the uterine volumes was 21.4%, 39.7%, 53.8% and 59.8% respectively at 1, 3, 6 and 12 months post-intervention. Dominant fibroid size was also significantly reduced after the procedure (5%, 18.5%, 26.8% and 32.9% reductions at 1, 3, 6 and 12 months, respectively; p < 0.01). Vaginal bleeding was abolished in all cases after the 12-month follow up. One patient needed to undergo hysterectomy 6 months after the procedure due to uncontrolled pain. Our results demonstrate uterine arteries embolization is minimally invasive and provides clinical control of the fibroids associated to significant reduction of the uterine volume. Moreover, the technique preserves the uterus and should be considered a therapeutic alternative to standard surgical treatment.
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Estudo genético-clínico e molecular da síndrome de Rokitansky-Mayer-Küster-Hauser e condições afins / Clinical, genetic and molecular study of Rokitansky-Mayer-Küster-Hauser syndrome and related conditionsCheroki, Carola 28 April 2008 (has links)
Introdução: A síndrome ou seqüência malformativa de Rokitansky-Mayer-Küster-Hauser (SR), de caráter geralmente esporádico, caracteriza-se por aplasia útero-vaginal, freqüentemente associada a anomalias esqueléticas e do trato urinário e a caracteres sexuais secundários, hormônios esteróides e cariótipo normais. A condição é claramente heterogênea, podendo fazer parte de outras seqüências e complexos mais abrangentes. Sua freqüência ao nascimento foi estimada em cerca de 1/5.000 meninas. O banco de dados OMIM (McKusick, 2005) classifica-a como autossômica recessiva e apenas um caso atípico, portador de virilização, foi atribuído a mutação descrita no gene WNT4 (Biason-Laubert e col.., 2004). A vitamina A e seus derivados ativos (ácidos retinóicos ou AR) desempenham papel importante nos processos de diferenciação, proliferação e apoptose celular. Mendelsohn e col. (1994) e Kastner e col. (1997) descreveram malformações congênitas semelhantes afins às da SR em camundongos portadores de mutações nos genes RAR-G e RXR-A dos receptores de AR. A região homóloga em humanos de um desses receptores corresponde exatamente à região descrita por Kucheria e col. (1988) em duas mulheres não aparentadas com agenesia mülleriana e portadoras de translocação (12;14)(q14;q31). Os fatores etiológicos responsáveis pelas anomalias müllerianas são ainda pouco conhecidos, mas o achado freqüente de afetadas com outros defeitos associados (renais, esqueléticos, cardíacos e auditivos) sugere o envolvimento de genes primordiais do desenvolvimento. Materiais e métodos: No total, 43 pacientes (todas com cariótipo 46,XX) e 21 familiares foram todos submetidos a exame clínico e ginecológico e de imagem (ultra-sonografia urogenital e raios-X de coluna) padronizados e à coleta de sangue para estudo cromossômico e molecular. O DNA foi extraído e amplificado por PCR Touch-Down; a triagem das mutações foi realizada em cinco genes (RARG, RXR-A, WNT-4, LHX-1 e KLHL-4) por eletroforese SSCP, dHPLC e de seqüenciamento (MegaBace). Quinze pacientes do total apresentando fenótipo mais grave foram triadas quanto a variações no número de cópias de DNA pela técnica de ~1 Mb array-CGH. As alterações detectadas foram validadas por FISH e MLPA. Foram excluídas alterações no número de cópias previamente descritas em indivíduos normais (DGV). Dois novos genes (LHX-1 e KLHL-4) surgiram como possíveis candidatos após a triagem com array- CGH e foram incluídos aos três genes candidatos previamente existentes. Resultados e conclusão: Trinta e nove pacientes possuíam quadro bastante típico de SR com agenesia útero-vaginal, em 27 delas acompanhado de manifestações extra-genitais como defeitos renais, ósseos, agenesia de ovários e surdez. Quatro pacientes apresentaram defeitos müllerianos isolados (agenesia de vagina) e uma outra era portadora da associação MURCS. A analise molecular por meio das técnicas de SSCP, dHPLC e seqüenciamentode todas as regiões codificados dos cinco genes candidatos permitiu identificar 95 alterações. A comparação com os bancos de dados (http://www.ensembl.org/) determinou que as alterações identificadas correspondem a variações populacionais polimórficas previamente descritas e sem efeito patogênico, uma vez que nenhuma delas altera a seqüência de aminoácidos das proteínas por elas codificadas. Mediante array-CGH foram identificadas, em 5 pacientes, um total de 7 alterações submicroscópicas (deleções e duplicações) comprometendo as regiões 1q21.1, 17q12, 22q11.21, 22q11.22, e Xq21.31. Alguns familiares das afetadas, também portadores dessas alterações, apresentavam manifestações leves, indicando que as alterações apresentam penetrância incompleta e expressividade variável. Nossos resultados afastam a RAR-G, RXR-A, WNT-4 como diretamente envolvidos na patogênese da síndrome de Rokitansky e sugerem a existência de variações no numero de copias de novas regiões cromossômicas como relevantes durante o desenvolvimento mülleriano, indicando especificamente os genes LHX1 e KLHL4 como candidatos. / Background: Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome, comprising utero-vaginal atresia in otherwise phenotypically normal women with a normal karyotype (46,XX), has an incidence of about 1/5,000 among newborn girls. Anomalies of the genital tract range from upper vaginal atresia to total Müllerian agenesis (congenital absence of the Fallopian tubes, uterus, and upper vagina). Patients with müllerian aplasia (MA) often exhibit additional clinical features such as renal, vertebral and cardiac defects. A number of different syndromes have been associated with MA, and in most cases its aetiology remains poorly understood. We studied 43 women with the MRKH defect and 21 relatives presenting associated anomalies. The study included clinical and ultrasonographic examination of the urogenital system, radiographs of the vertebral column and sequencing of three candidate genes named RAR gama, RXR alpha and WNT-4. Fifteen of our patients, with more complex phenotypes (genital, renal, cardiac, and skeletal defects), were screened for DNA copy number changes by 1 Mb whole genome bacterial artificial chromosome (BAC) array based comparative genomic hybridization (CGH). The detected alterations were validated by an independent method and further mapped by high resolution oligo-arrays. Results: All patients had a normal 46,XX karyotype and were also normal to the RAR gama, RXR alpha and WNT-4 genes. Submicroscopic genomic imbalances affecting the 1q21.1, 17q12, 22q11.21, and Xq21.31 chromosome regions were detected in five probands. Presence of the alterations in the normal mother of one patient suggests incomplete penetrance and/or variable expressivity. Conclusion: 5 of the 15 patients were found to have cryptic genomic alterations. The imbalances on 22q11.21 support recent findings by us and others that alterations in this chromosome region may result in impairment of müllerian duct development. The remaining imbalances indicate involvement of previously unknown chromosome regions in MA, and point specifically to LHX1 and KLHL4 as candidate genes.
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Tratamento das pacientes sintomáticas portadoras de miomas uterinos através da associação das técnicas de embolização dos miomas e ligadura endovascular das artérias uterinas / Uterine artery embolization with polyvinyl-alcohol particles and metallic coils for the treatment of symptomatic patients with fibroidsPinto, Ricardo Augusto de Paula 27 March 2007 (has links)
Os miomas uterinos são os tumores benignos mais comuns do trato genital feminino, sendo que nas mulheres portadoras, 30% são sintomáticos e exigem alguma forma de tratamento. No presente estudo, foram tratadas 35 pacientes sintomáticas com diagnóstico clínico e ultra-sonográfico de mioma uterino, por meio da embolização dos miomas com partículas de polivinil-álcool associadas à obstrução das artérias uterinas com micromolas fibradas. A avaliação clínica e ecográfica foram inicialmente feitas e o acompanhamento realizado após um, três, seis e doze meses do procedimento. O sucesso técnico foi de 94,3%. O volume uterino médio era de 404,53 cm3 antes do tratamento endovascular percutâneo e o sintoma mais freqüente, em 82,9%, a menorragia. A redução média dos volumes uterinos foi de 21,4%, 39,7%, 53,8% e 59,8% respectivamente em um, três, seis e 12 meses (p < 0,01). Houve, também, a redução do volume do nódulo miomatoso dominante em 5%, 18,5%, 26,8% e 32,9% em um, três, seis e 12 meses, respectivamente (p < 0,01). A melhora e o controle da menorragia foram obtidos em 100% das pacientes tratadas. Houve necessidade de histerectomia em uma paciente por insucesso no controle da dor após seis meses do procedimento. A embolização dos miomas uterinos com partículas de polivinil-álcool associada à oclusão endovascular das artérias uterinas com micromolas fibradas é uma alternativa de tratamento minimamente invasivo para as pacientes sintomáticas portadoras de miomas uterinos que proporciona controle e melhora dos sintomas e redução do tamanho dos miomas e do volume uterino. / Uterine fibroids are the most frequent benign tumors of the female genital tract. The tumors are symptomatic in about 30% of the cases, requiring medical treatment. In the present study, a total of 35 clinically symptomatic patients with ultrasonographic diagnosis of fibroids underwent endovascular treatment, which consisted of embolization of the uterine arteries with 355-500 micras PVA particles associated to metallic coils. Clinical and ultrasonographic evaluations were performed at baseline, 1, 3, 6 and 12 months post-intervention. Technical success was obtained in 94.3% of the cases. Mean uterine volume before the procedure was 404.53 cm³ and menorrhagia was the most frequent symptom (82.9%). Mean reduction of the uterine volumes was 21.4%, 39.7%, 53.8% and 59.8% respectively at 1, 3, 6 and 12 months post-intervention. Dominant fibroid size was also significantly reduced after the procedure (5%, 18.5%, 26.8% and 32.9% reductions at 1, 3, 6 and 12 months, respectively; p < 0.01). Vaginal bleeding was abolished in all cases after the 12-month follow up. One patient needed to undergo hysterectomy 6 months after the procedure due to uncontrolled pain. Our results demonstrate uterine arteries embolization is minimally invasive and provides clinical control of the fibroids associated to significant reduction of the uterine volume. Moreover, the technique preserves the uterus and should be considered a therapeutic alternative to standard surgical treatment.
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”Det känns som att jag är ensam från midjan och uppåt” Negativa upplevelser av gynekologiska undersökningar hos de som undviker cellprovtagning / ”It Feels Like I am Alone From the Waist Up” Negative Experiences of Pelvic Exams Among Those Who Avoid Cervical ScreeningsJerdén, Maja, Jonsson, Idamaria January 2019 (has links)
No description available.
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Role de l’axe endothéline-1 et des map kinases dans la physiologie des leiomyomes utérins de rates / Role of endothelin-1 axis and MAP kinase in the physiology of rat uterine leiomyomasOyeniran, Clément 04 February 2011 (has links)
Nous montrons pour la première fois qu’en plus de la MAPK ERK1/2, l’endothéline-1 (ET-1) via les récepteurs ETA et ETB active une autre MAP kinase : la p38 uniquement dans les cellules de léiomyomes utérins de rate (ELT3) mais pas dans les cellules myométriales saines. Dans les cellules ELT3, l’analyse des voies de signalisation montre que malgré les similitudes observées entre les modes d’activation des voies p38 et ERK1/2 par ET-1, celles-ci sont activées de façon indépendante l’une de l’autre. En plus, la forskoline active p38 (mais pas ERK1/2), par contre l’activation de p38 par ET-1 n’implique pas une production d’AMPc. Par ailleurs ERK1/2 et p38 coactivées par ET-1 coopèrent pour augmenter l’expression de COX2 et la production des prostaglandines E2 (PGE2) pour favoriser l’effet antiapoptotique de ET-1. De plus p38 activée par ET-1 contribue à la prolifération des léiomyomes. Nos résultats élucident les mécanismes par lesquels ET-1 contribue à la croissance des léiomyomes. / We demonstrated for the first time, that in addition to the MAPK ERK1/2, Endothelin-1 (ET-1) through ETA and ETB receptors activated another MAP kinase: p38 only in uterine leiomyoma cells (ELT3) but not in normal myometrial cells. In ELT3 cells, analysis of signaling pathways showed that, despite the similarities between the mechanisms involved in the activation of p38 and ERK1/2 pathways by ET-1, these kinases are activated independently one of another. In addition, forskolin (a cAMP inducer), activated p38 (but not ERK1/2), whereas the activation of p38 by ET-1 did not involve production cAMP. Moreover the coactivated ERK1/2 and p38 pathways by ET-1 cooperated to increase expression of COX2 and prostaglandin E2 (PGE2) production. This PGE2 like ET-1 exerted an antiapoptotic effect in ELT3 cells. Furthermore, p38 activated by ET-1 contributes to the proliferation of ELT3 leiomyoma cells. Our data highlight the mechanisms by which ET-1 could promote uterine leiomyoma growth.
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Estudo de alterações gênicas em amostras de sarcomas e carcinossarcomas uterinos: identificação de mercadores para diagnóstico diferencial e tratamento / Study of gene alterations in uterine sarcomas and carcinosarcoma samplesCosta, Leonardo Tomiatti da 29 March 2018 (has links)
Os sarcomas uterinos são tumores mesodérmicos raros que compreendem cerca de 3% de todos os cânceres nesse órgão. Apresentam diversidade histológica, comportamento agressivo, disseminação precoce e altas taxas mortalidade. Recentemente, os carcinossarcomas (CS) foram reclassificados histologicamente como carcinomas. Neste trabalho, os CS foram incluídos na casuística tanto para fins de comparação de seu componente mesenquimal, como por ainda fazerem parte da maioria dos estudos sobre sarcomas de corpo uterino e também da última classificação da WHO (Word Health Organization). Devido à sua diversidade e raridade, não há consenso relacionado aos fatores de risco para pior prognóstico e tratamento adequados para esses tumores. Informações sobre seus perfis gênicos e proteicos poderiam contribuir na caracterização de marcadores moleculares que auxiliassem no diagnóstico e prognóstico desses tumores, bem como no entendimento de sua biologia e comportamento clínico. Assim, nos propusemos a avaliar a presença de alterações gênicas nesses tumores, utilizando um painel de 409 genes, oncogenes e supressores de tumor, frequentemente mutados em tumores sólidos. Para isso, foram selecionadas 66 amostras, das quais 14 foram sequenciadas, incluindo, 5 carcinossarcomas (CCS), 4 leiomiossarcomas (LMS), 4 sarcomas de estroma endometrial (SEE) e 1 adenossarcoma (ADS). As reações foram realizadas utilizando a plataforma Ion Proton System (ThermoFisher) de Sequenciamento de Nova Geração. Nas 14 amostras encontramos 27 LoF e 40 mutações missenses, numa média de 39 inserções e 52 deleções por amostra, totalizando 70 mutações. Dessas, 25 encontram-se no banco de dados COSMIC. Os genes mais comumente mutados em nossa amostragem foram: TP53 (50%), KMT2D (36%), ATM (29%), DICER1 (21%), PIK3CA (21%), TRRAP (21%). Nosso objetivo principal era encontrar mutações específicas para cada subtipo histológico, porém apenas os SEEs (PDE4DIP) e os CCS (ERBB4 e PIK3CA) tiveram mutações especificas. Em outra análise, observamos que todos os subtipos histológicos compartilham o gene KMT2D. Embora não tenha sido possível estabelecer um perfil mutacional para cada subtipo histológico avaliado, nossos resultados abrem perspectivas para uma nova linha de pesquisa nos sarcomas de corpo do útero e certamente contribuem para um melhor entendimento dessas neoplasias / Uterine sarcomas are rare mesodermal tumors that comprise about 3% of all cancers in this organ. They present histological diversity, aggressive behavior, early dissemination and high mortality rates. Recently, carcinosarcomas (CCS) were histological reclassified as carcinomas. Here, we have included them in our series for purposes of comparison of the mesenchymal component and also because these tumors still form part of both the majority of studies and the WHO\'s latest classification for uterine sarcomas (Word Health Organization). Because of their diversity and rarity, there is no consensus regarding the risk factors for poor prognosis and appropriate treatment for these tumors. Thus, information about their gene and protein profiles can help in the diagnosis and prognosis of these tumors, as well as in the understanding of their biology and clinical behavior. We performed the New Generation Sequencing of 14 samples of uterine sarcomas (5 CCS, 4 LMS, 4 SEE and 1 ADS, using the Ion Proton System platform (ThermoFisher).) Among the 14 samples, we found 27 LoF (loss of gene function) and 40 missense mutations, with a mean of 39 insertions and 52 deletions per sample, totaling 70 mutations, 25 described in the COSMIC database. The most commonly mutated genes in our sample were TP53 (50%), KMT2D (36%), ATM (29%), DICER1 (21%), PIK3CA (21%), TRRAP (21%).Our main objective was to find specific mutations for each histological subtype, but only SEEs (PDE4DIP) and CCS (ERBB4 and PIK3CA) had specific mutations. In another analysis, we observed that all the histological subtypes share the KMT2D gene, which will be studied in future analyzes. Others analyzes, using a custom panel, are necessary to understand these mutations and its biological implication in uterine carcinosarcoma and sarcomas
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Les voies de signalisation utérines à l'émergence de la diapause embryonnaire chez le vison américainLefèvre, Pavine L.C. 08 1900 (has links)
La diapause embryonnaire se manifeste par un arrêt réversible du développement embryonnaire durant la période de préimplantation et induit un retard de l’implantation. Chez le vison américain, une diapause embryonnaire obligatoire caractérise chaque gestation. Si les mécanismes de contrôle de la diapause embryonnaire obligatoire chez cette espèce sont bien connus, le rôle utérin impliqué dans la réactivation de l’embryon demeure, quant à lui, encore inconnu.
Le sujet de ce doctorat a consisté dans un premier temps à explorer l’environnement utérin à la sortie de la diapause embryonnaire afin de caractériser, dans un deuxième temps, les principaux acteurs utérins qui provoquent la réactivation de l’embryon.
Nous avons effectué une analyse du transcriptome utérin à l’émergence de la diapause embryonnaire ce qui a permis de construire une librairie de 123 séquences d’ADNc utérines différentiellement exprimées à la réactivation de l’embryon et homologues à des séquences de gènes connues chez d’autres espèces. Ces gènes sont impliqués dans la régulation du métabolisme (25 %), de l’expression génique (21 %), de la transduction de signal (15 %), du cycle cellulaire (15 %), du transport (10 %) et de la structure cellulaire (9 %), reflétant ainsi d’importantes modifications utérines à la réactivation embryonnaire. Nous avons validé l’expression différentielle de dix gènes ainsi identifiés : GDF3 (growth and differentiation 3), ALCAM (activated leukocyte cell adhesion molecule), ADIPOR1 (adiponectin receptor 1), HMGN1 (high mobility group N1), TXNL1 (thioredoxin like 1), TGM2 (tissue transglutaminase 2), SPARC (secreted protein acidic rich in cystein), et trois gènes codant pour AZIN1 (antizyme inhibitor 1), ODC1 (ornithine decarboxylase 1) et SAT1 (spermidine/spermine N1-acetyltransferase), des enzymes impliquées dans la biosynthèse des polyamines. Le patron de l’expression spatio-temporel de SPARC et d’HMGN1 illustrent spécifiquement un remodelage tissulaire et de la chromatine au niveau utérin à la sortie de la diapause embryonnaire.
Ayant mesuré une augmentation des concentrations utérines en polyamines à la reprise du développement embryonnaire, nous avons émis l’hypothèse que les polyamines seraient impliquées dans les événements menant à la sortie de la diapause. L’inhibition de la biosynthèse des polyamines par un traitement à l’ α-difluoromethylornithine (DFMO) a provoqué une diminution significative de la proliferation cellulaire dans les embryons à la réactivation, un retard du moment de l’implantation, mais n’a pas affecté le succès de la reproduction. De manière similaire, nous avons induit un état de dormance dans les cellules de trophoblaste de vison en présence DFMO dans le milieu de culture, et constaté que cet état était réversible.
En conclusion, cette étude a non seulement ouvert de nouveaux horizons quant à la compréhension du rôle utérin dans les événements menant à la sortie de la diapause embryonnaire, mais a démontré pour la première fois, l’existence de facteurs utérins indispensables à la réactivation de l’embryon: les polyamines. / Embryonic diapause is characterized by a reversible arrest of blastocyst development prior to implantation and delay in implantation. In the American mink, embryonic diapause is a characteristic of each gestation. Although the mechanisms which control obligate embryonic diapause of this species are well known, the role of the uterus involved in blastocyst reactivation remains elusive.
The subject of this doctoral research consisted first in exploring the uterine environment at the emergence of embryonic diapause in order to subsequently determine, the main factors in the uterus that provoke reactivation of the embryo.
We have undertaken an analysis of the uterine transcriptome at the emergence of embryonic diapause which has enabled us to set up a library of 123 cDNA uterine sequences differentially expressed at blastocyst reactivation, and homologue gene sequences known in other species. Twenty-five percent of these genes are implicated in genetic expression, 15 % in cell signal transduction, 15 % in cell cycle, 10 % in transport and 9 % in cell structure. All of them reflect significant uterine modifications at blastocyst reactivation. We have validated differential expression of ten genes, identified as: GDF3 (growth and differentiation 3), ALCAM (activated leukocyte cell adhesion molecule), ADIPOR1 (adiponectin receptor 1), HMGN1 (high mobility group N1), TXNL1 (thioredoxine like 1), TGM2 (tissue transglutaminase 2), SPARC (secreted protein acidic rich in cystein), and three genes encoding for AZIN1 (antizyme inhibitor 1), ODC1 (ornithine decarboxylase 1) and SAT1 (spermidine/spermine N1-acetyltransferase), which are enzymes implicated in polyamine biosynthesis. The spatio-temporal expression patterns of SPARC and HMGN1 illustrate tissue and chromatin remodelling in the uterus at the termination of embryonic diapause.
Having measured an increase in concentration of polyamines in the uterus at the resumption of blastocyst development, we have hypothetized that polyamines are implicated in the emergence of blastocysts from diapause. We inhibited polyamine biosynthesis in pregnant mink females during early blastocyst reactivation. The inhibition of polyamine biosynthesis through treatment with α-difluoromehtylornithine (DFMO) provoked a major reduction in cell proliferation in blastocysts at reactivation and a delay in the timing of implantation, but did not affect the success of reproduction. Similarly, we induced a reversible dormant state in cultured mink trophoblast cells traited with DFMO.
To conclude, not only are results of this study a breakthrough in the understanding of the role of the uterus in stimulating at the emergence of blastocysts from embryonic diapause, but also, for the very first time, they indicate the existence of uterine factors, the polyamines, that are responsible for blastocysts reactivation.
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