Le développement dune placentation hémochoriale requiert une invasion trophoblastique de lendomètre maternel jusquà ses couches profondes ainsi quune érosion des vaisseaux maternels jusquau niveau du tiers supérieur du myomètre. Les cellules trophoblastiques envahissent et modifient les vaisseaux utérins pour permettre une augmentation du flux sanguin vers lunité foeto-placentaire. Dautre part, lembryon qui simplante va non seulement se connecter aux vaisseaux maternels mais aussi générer des vaisseaux de novo. Le processus dangiogenèse endométriale au niveau du site dimplantation est modulé spatio-temporellement par un dialogue complexe entre des facteurs endocrines, paracrines et autocrines. Parmi ces facteurs, lhCG, sécrétée précocement par le trophoblaste, va tenir un rôle de choix. Outre son rôle lutéotrophique bien décrit, lhCG promeut linvasion trophoblastique et présente une action clé sur la tolérance maternelle de lembryon. Nos travaux ont mis en évidence un rôle direct de lhCG sur langiogène endométriale ainsi quun rôle indirect via une boucle paracrine par activation du récepteur hCG/LH à la surface des cellules endothéliales et épithéliales de lendomètre et une stimulation de lexpression du VEGF dans les cellules épithéliales sous linfluence de lhCG. Grâce à de nombreux modèles dangiogenèse in vitro, in vivo et ex-vivo, nous avons décrypté la signalisation cellulaire mise en uvre lors de la liaison de lhCG à son récepteur. De plus, nos travaux démontrent un rôle artériogène inattendu de cette hormone. Ceci revêt toute son importance dans létude de leffet angiogène de lhCG lié à des processus physiologiques comme langiogenèse au niveau du site dimplantation, pathologiques comme leffet tumorigène de lhCG sécrété en fortes quantités lors de pathologies trophoblastiques.

Thioredoxin is a small ubiquitous oxido-reductase found in all species. The highly conserved active site, which facilitates thioredoxins redox activity, contains two redox active cysteine residues. Thioredoxin has numerous protein substrates to which it donates H+ ions and it can also function as a free radical scavenger. Through these activities thioredoxin is able to influence the redox state of not only its protein targets, but also the entire cellular environment. Thioredoxin has been implicated in many biological functions, and one mechanism by which it influences these functions is through interactions with a number of transcription factors including NF-kappa-B and p53. Thioredoxin also has numerous extracellular biological roles. It has been shown that thioredoxin is actively secreted from a number of normal and transformed cell lines including fibroblasts and activated B and T cells. This study investigates the role of thioredoxin in embryonic implantation and cancer cell metastasis, two physiological functions which rely on the same basic processes. Thioredoxin expression has previously been shown to be increased in many cancers. However it has not yet been established whether this increase is a causative or a side effect of the cancerous phenotype. Similarly thioredoxin expression has previously been shown to be increased during different phases of the oestrus cycle and pregnancy. This thesis describes the role of thioredoxin in embryonic implantation using a marmoset model. A thioredoxin cDNA was isolated and subsequently sequenced. Preliminary antibody experiments indicated that the anti human thioredoxin monoclonal antibodies available in our laboratory would recognise marmoset thioredoxin. Subsequently immunocytochemistry using anti human thioredoxin antibodies was carried out on sectioned marmoset uterus and embryonic tissue. The results indicated that thioredoxin is expressed by cells at the embryonic-maternal interface of early implantation sites. Further studies demonstrated that thioredoxin is also expressed and secreted by cultured blastocysts in vitro. This thesis also describes the role of thioredoxin in cancer cell metastasis. Results of this study indicate that thioredoxin is actively involved in facilitating the invasive phenotype of breast cancer cells. The two cell lines utilised were MCF-7, a well differentiated, relatively non-invasive breast cancer cell line; and MDA-MB-231, a poorly differentiated, highly invasive breast cancer cell line. The cell lines were transfected with thioredoxin sense, antisense and 1SS (encodes thioredoxin with both active cysteine residues mutated to serine residues and is thus redox inactive) constructs. The results demonstrate that when endogenous thioredoxin levels are increased, i.e. transfected with a sense thioredoxin construct, the invasive breast cancer cell line MDA-MB-231 becomes more invasive, conversely when endogenous levels are decreased, i.e. transfected with antisense or 1SS constructs, the invasive capacity of these cells decreases. However, when the endogenous level of thioredoxin was manipulated in the relatively non-invasive cell line MCF-7 very little effect was observed. Results also indicate that thioredoxin has the ability to act as a chemoattractant for actively invading breast cancer cells. Both of these functions appear to be dependent on thioredoxin's redox activity. Additional studies described in this thesis have shown that thioredoxin is involved in the regulation of Sp1 in vitro. Sp1 is a transcription factor known to regulate the transcription of a number of genes whose products are intimately involved in the invasive phenotype. The results in this study suggest that Sp1 DNA binding is regulated by thioredoxin such that when reduced by the enzyme its binding to DNA is facilitated. Results also indicate that Sp1 may regulate the transcription of thioredoxin by binding to Sp1 sites within the thioredoxin promoter.

Evidências epidemiológicas associam diferentes fatores ambientais, tais como poluição e ingestão de alimentos contaminados, com desfechos gestacionais negativos e fertilidade diminuída em humanos. Não há duvidas de que a poluição do ar nos grandes centros urbanos é capaz de provocar desfechos negativos sobre a gestação: baixo peso ao nascer, prematuridade, perda gestacional, entre outros. Entretanto, poucos estudos foram conduzidos para avaliar um possível efeito da exposição à poluição ambiental particulada do ar sobre a saúde reprodutiva feminina. O objetivo deste trabalho foi avaliar se a exposição subcrônica a poluição atmosférica particulada da cidade de São Paulo é capaz de alterar a receptividade uterina à implantação embrionária. Para tanto, foram avaliados 3 grupos de fêmeas de camundongos (n=10), expostas cronicamente desde o período de desmame (PND21) até atingirem a idade reprodutiva (PND60) à duas concentrações de MP2,5 (600?g/m3 ou 1200ug/m3) ou ar filtrado. Diferentes parâmetros relacionados à fertilidade e a receptividade uterina foram avaliados. Nossos achados mostram que a exposição ao material particulado de origem veicular provoca alterações na ciclicidade estral prévia ao acasalamento, bem como um aumento no peso dos ovários. Avaliação da reserva folicular indica que há um aumento na quantidade de folículos médios associado à exposição a menor concentração de MP (p=0,04). A avaliação histopatológica do tecido uterino revelou que há aumentos na fração de volume das glândulas uterinas (600ug/m3; p=0,01); o epitélio glandular (p=0,001) e luminal (p=0,03) estão espessados e o diâmetro médio das glândulas uterinas foi maior nos grupos expostos ao MP (p=0,004). A análise qualitativa da distribuição de pinopódios no epitélio luminal por microscopia eletrônica de varredura e transmissão indica que há uma redução na presença destas estruturas. A avaliação da expressão de LIF por imunomarcação mostrou-se reduzida no epitélio luminal (p<0,001), nas glândulas (p<0,001) e estroma (p=0,004) nas fêmeas expostas ao MP, porém nenhuma diferença foi observada na expressão de MUC-1 (mucina). Entretanto quando avaliadas a expressão gênica de MUC-1 e LIF no tecido uterino e os níveis de IL-1beta e IL-6 no fluído uterino nenhuma diferença foi observada entre os grupos. Com base em nossos achados conclui-se que a exposição à poluição particulada do ar de origem veicular pode estar envolvida no aumento das perdas gestacionais e/ou implantacionais pelo comprometimento da receptividade uterina provavelmente pelo prejuízo do remodelamento uterino necessário a implantação / Epidemiological evidences have shown that environmental factors, such as environmental pollution and ingestion of contaminated food, are associated with negative gestational outcomes and decreased fertility in human. There is no doubt that exposure to air pollution in large urban areas are capable of impairing health (e.g. hypertension) and of aggravating preexisting diseases (e.g asthma). However, the effects of air pollution exposures on female reproductive health are lesser known. Previous experimental studies have shown that low birth weights are reduced and embryonic implantational index are reduced in animals exposed to ambient levels of air pollution. The aim of this study was to evaluate if sub chronic exposures to particulate air pollution before pregnancy and during the initial stages is capable to alter the uterine receptivity of mice. To test this, 3 groups of female mice were continually exposed from 21st to 60th postnatal day to either filtered or two different doses of concentrated ambient particles (MP2,5 - 600ug/m3 or 1200ug/m3) with the aid of a Ambient Particle Concentrator and different parameters associated with fertility and uterine receptivity were evaluated. Or data have shown that exposures to particulate air pollution from vehicular origin are associated to changes in estrous ciclicity, cycles are shorter and the number of days in estrous reduced. Evaluation of the follicular reserve also indicates that animals exposed to MP present an increased number of ovarian medium follicles (p=0.04). Histopathological evaluation of the uterine tissue revealed increases in the volume fraction of uterine glands (p= 0.01) of those animals exposed to 600ug/m3. The luminal (p= 0.03) and glandular epithelium (p= 0,001) are thicker and the uterine glands diameters (p=0,004) were greater in exposed animals. Qualitative analysis by transmission and scanning electron microscopy indicates that there is a reduction in the presence of pinopódios in the luminal epithelium of PM exposed females. The expressions of LIF assessed by immunohistochemistry in those females exposed to PM were reduced in the luminal epithelium (p<0,001), and in the glandular (p<0,001) and stromal compartments as well. However no differences in the expression of MUC-1 were seen. Gene expression of LIF and MUC-1 in the whole endometrium (qPCR) and the expression of IL-6 and IL-1beta in the uterine fluid did not show significant difference between the groups tested. In conclusion, our data have shown that exposures to ambient air particulate pollution can be associated with increased rates of implantational losses due to changes in the uterine receptivity related to factors involved in uterine remodeling for pregnancy

Evidências epidemiológicas associam diferentes fatores ambientais, tais como poluição e ingestão de alimentos contaminados, com desfechos gestacionais negativos e fertilidade diminuída em humanos. Não há duvidas de que a poluição do ar nos grandes centros urbanos é capaz de provocar desfechos negativos sobre a gestação: baixo peso ao nascer, prematuridade, perda gestacional, entre outros. Entretanto, poucos estudos foram conduzidos para avaliar um possível efeito da exposição à poluição ambiental particulada do ar sobre a saúde reprodutiva feminina. O objetivo deste trabalho foi avaliar se a exposição subcrônica a poluição atmosférica particulada da cidade de São Paulo é capaz de alterar a receptividade uterina à implantação embrionária. Para tanto, foram avaliados 3 grupos de fêmeas de camundongos (n=10), expostas cronicamente desde o período de desmame (PND21) até atingirem a idade reprodutiva (PND60) à duas concentrações de MP2,5 (600?g/m3 ou 1200ug/m3) ou ar filtrado. Diferentes parâmetros relacionados à fertilidade e a receptividade uterina foram avaliados. Nossos achados mostram que a exposição ao material particulado de origem veicular provoca alterações na ciclicidade estral prévia ao acasalamento, bem como um aumento no peso dos ovários. Avaliação da reserva folicular indica que há um aumento na quantidade de folículos médios associado à exposição a menor concentração de MP (p=0,04). A avaliação histopatológica do tecido uterino revelou que há aumentos na fração de volume das glândulas uterinas (600ug/m3; p=0,01); o epitélio glandular (p=0,001) e luminal (p=0,03) estão espessados e o diâmetro médio das glândulas uterinas foi maior nos grupos expostos ao MP (p=0,004). A análise qualitativa da distribuição de pinopódios no epitélio luminal por microscopia eletrônica de varredura e transmissão indica que há uma redução na presença destas estruturas. A avaliação da expressão de LIF por imunomarcação mostrou-se reduzida no epitélio luminal (p<0,001), nas glândulas (p<0,001) e estroma (p=0,004) nas fêmeas expostas ao MP, porém nenhuma diferença foi observada na expressão de MUC-1 (mucina). Entretanto quando avaliadas a expressão gênica de MUC-1 e LIF no tecido uterino e os níveis de IL-1beta e IL-6 no fluído uterino nenhuma diferença foi observada entre os grupos. Com base em nossos achados conclui-se que a exposição à poluição particulada do ar de origem veicular pode estar envolvida no aumento das perdas gestacionais e/ou implantacionais pelo comprometimento da receptividade uterina provavelmente pelo prejuízo do remodelamento uterino necessário a implantação / Epidemiological evidences have shown that environmental factors, such as environmental pollution and ingestion of contaminated food, are associated with negative gestational outcomes and decreased fertility in human. There is no doubt that exposure to air pollution in large urban areas are capable of impairing health (e.g. hypertension) and of aggravating preexisting diseases (e.g asthma). However, the effects of air pollution exposures on female reproductive health are lesser known. Previous experimental studies have shown that low birth weights are reduced and embryonic implantational index are reduced in animals exposed to ambient levels of air pollution. The aim of this study was to evaluate if sub chronic exposures to particulate air pollution before pregnancy and during the initial stages is capable to alter the uterine receptivity of mice. To test this, 3 groups of female mice were continually exposed from 21st to 60th postnatal day to either filtered or two different doses of concentrated ambient particles (MP2,5 - 600ug/m3 or 1200ug/m3) with the aid of a Ambient Particle Concentrator and different parameters associated with fertility and uterine receptivity were evaluated. Or data have shown that exposures to particulate air pollution from vehicular origin are associated to changes in estrous ciclicity, cycles are shorter and the number of days in estrous reduced. Evaluation of the follicular reserve also indicates that animals exposed to MP present an increased number of ovarian medium follicles (p=0.04). Histopathological evaluation of the uterine tissue revealed increases in the volume fraction of uterine glands (p= 0.01) of those animals exposed to 600ug/m3. The luminal (p= 0.03) and glandular epithelium (p= 0,001) are thicker and the uterine glands diameters (p=0,004) were greater in exposed animals. Qualitative analysis by transmission and scanning electron microscopy indicates that there is a reduction in the presence of pinopódios in the luminal epithelium of PM exposed females. The expressions of LIF assessed by immunohistochemistry in those females exposed to PM were reduced in the luminal epithelium (p<0,001), and in the glandular (p<0,001) and stromal compartments as well. However no differences in the expression of MUC-1 were seen. Gene expression of LIF and MUC-1 in the whole endometrium (qPCR) and the expression of IL-6 and IL-1beta in the uterine fluid did not show significant difference between the groups tested. In conclusion, our data have shown that exposures to ambient air particulate pollution can be associated with increased rates of implantational losses due to changes in the uterine receptivity related to factors involved in uterine remodeling for pregnancy