Embryonic stem (ES) cells offer a valuable source for generating insulin-producing cells. However, current differentiation protocols often result in heterogeneous cell populations of various developmental stages. Here we show the activin A-induced differentiation of mouse ES cells carrying a homologous dsRed-IRES-puromycin knock-in within the Sox17 locus into the endoderm lineage. Sox17-expressing cells were selected by fluorescence-assisted cell sorting (FACS) and characterized at the transcript and protein level. Treatment of ES cells with high concentrations of activin A for 10 days resulted in up to 19% Sox17-positive cells selected by FACS. Isolated Sox17-positive cells were characterized by defini- tive endoderm-specific Sox17/Cxcr4/Foxa2 transcripts, but lacked pluripotency-associated Oct4 mRNA and protein. The Sox17-expressing cells showed downregulation of extraembryonic endoderm (Sox7, Afp, Sdf1)-, mesoderm (Foxf1, Meox1)- and ectoderm (Pax6, NeuroD6)-specific transcripts. The presence of Hnf4α, Hes1 and Pdx1 mRNA demonstrated the expression of primitive gut/foregut cell-specific markers. Ngn3, Nkx6.1 and Nkx2.2 transcripts in Sox17-positive cells were determined as properties of pancreatic endocrine progenitors. Immunocytochemistry of activin A-induced Sox17-positive embryoid bodies revealed coexpression of Cxcr4 and Foxa2. Moreover, the histochemical demonstration of E-cadherin-, Cxcr4-, Sox9-, Hnf1β- and Ngn3-positive epithelial-like structures underlined the potential of Sox17-positive cells to further differentiate into the pancreatic lineage. By reducing the heterogeneity of the ES cell progeny, Sox17-expressing cells are a suitable model to evaluate the effects of growth and differentiation factors and of culture conditions to delineate the differentiation process for the generation of pancreatic cells in vitro. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O objetivo deste estudo foi investigar os nÃveis de RNA mensageiro (RNAm) para ativina-A em folÃculos prÃ-antrais e antrais caprinos e os efeitos do hormÃnio folÃculo estimulante (FSH), ativina-A e fator de crescimento e diferenciaÃÃo - 9 (GDF-9) sobre o crescimento e a expressÃo de RNAm para ativina-A, GDF-9, proteÃna morfogenÃtica Ãssea (BMP) -2, -4, -6, -7, -15 e receptor de FSH (R-FSH) em folÃculos prÃ-antrais caprinos cultivados in vitro. Inicialmente, folÃculos primordiais, primÃrios e secundÃrios, bem como complexos cumulus-oÃcito (COCs) e cÃlulas da granulosa mural/teca de pequenos e grandes folÃculos antrais foram isoladas mecanicamente a partir de ovÃrios de cabra e a expressÃo de RNAm para ativina-A foi avaliada por PCR em tempo real. Para os estudos in vitro, folÃculos secundÃrios caprinos foram isolados e cultivados por 6 dias na presenÃa de FSH sozinho (50 ng/mL) ou em combinaÃÃo com ativina-A (100 ng/mL) ou GDF-9 (200 ng/mL). Isoladamente ou em combinaÃÃo com FSH, a influÃncia de ativina-A na expressÃo de ativina-A e R-FSH, e o efeito do GDF-9 sobre os nÃveis de RNAm para GDF-9, R-FSH e BMP -2, -4 , -6, -7 e -15 em folÃculos secundÃrios apÃs 6 dias de cultivo foram testados. Para isso, apÃs a extraÃÃo do RNA total e sÃntese do cDNA, os nÃveis de RNAm para ativina-A, GDF-9, R-FSH e BMP -2, -4, -6, -7 e -15 foram quantificados por PCR em tempo real. Os resultados mostraram que folÃculos secundÃrios apresentavam nÃveis menores de RNAm para ativina-A comparado aos folÃculos primÃrios (p<0,05). NÃo houve diferenÃa nos nÃveis de RNAm para ativina-A entre folÃculos primordial e primÃrio ou secundÃrio (p>0,05). Aliado a isso, nÃo houve diferenÃa entre COCs de pequenos e grandes folÃculos antrais (p>0,05). AlÃm disso, as cÃlulas da granulosa e da teca de grandes folÃculos antrais apresentaram maiores nÃveis de RNAm para ativina-A do que de pequenos folÃculos antrais (p<0,05). Quando comparamos a expressÃo do RNAm para ativina-A entre COCs de pequenos e grandes folÃculos antrais e suas cÃlulas da granulosa e da teca, nenhuma diferenÃa nos nÃveis de expressÃo foi observada (p>0,05). ApÃs o cultivo in vitro de folÃculos secundÃrios, a presenÃa de FSH sozinho ou associado com ativina-A ou GDF-9 aumentou a sobrevivÃncia, crescimento folicular e formaÃÃo de antro (p<0,05). O FSH tambÃm aumentou o RNAm para ativina-A, enquanto os folÃculos cultivados com ativina-A apresentaram nÃveis aumentados de RNAm para R-FSH (p<0,05). AlÃm disso, o GDF-9 diminuiu a expressÃo de RNAm para BMP -2 e -15 (p<0,05), mas nÃo teve efeito sobre a expressÃo de BMP -4, -6 e -7 (p>0,05). Em conclusÃo, durante a transiÃÃo de folÃculo primÃrio para secundÃrio hà uma diminuiÃÃo do RNAm para ativina-A, enquanto ocorre um aumento da expressÃo deste fator durante o crescimento de folÃculos antrais. FSH, ativina-A e GDF-9 estimulam o crescimento de folÃculos secundÃrios caprinos apÃs 6 dias de cultivo. ApÃs cultivo folicular, FSH controla a expressÃo de ativina-A e a expressÃo do R-FSH à regulada por ativina-A. Ainda, GDF-9 reduz a expressÃo do RNAm para BMP -2 e -15. / The aim of this study was to investigate the levels of messenger RNA (mRNA) for activin-A on goat preantral and antral follicles and the effects of follicle stimulating hormone (FSH), activin-A and growth and differentiation factor - 9 (GDF-9) on growth and mRNA expression for activin-A, GDF-9, bone morphogenetic protein (BMP) -2, -4, -6, -7, -15 and FSH receptor (FSH-R) in goat preantral follicles cultured in vitro. Initially, primordial, primary and secondary follicles, as well as cumulus-oocyte complexes (COCs) and mural granulosa/theca cells of small and large antral follicles were isolated mechanically from goat ovaries and the expression of mRNA for activin-A was evaluated by real-time PCR. For in vitro studies, goat secondary follicles were isolated and cultured for 6 days in the presence of FSH alone (50 ng/mL) or in combination with activin-A (100 ng/mL) or GDF-9 (200 ng/mL). Alone or in combination with FSH, the influence of activin-A on expression of activin-A and FSH-R, and the effect of GDF-9 on the levels of mRNA for GDF-9, FSH-R and BMP -2, -4, -6, -7 and -15 in secondary follicles after 6 days of culture were tested. For this, after extraction of total RNA and cDNA synthesis, the levels of mRNA for activin-A, GDF-9, FSH-R and BMP -2, -4, -6, -7 and -15 were quantified by real time PCR. The results showed that secondary follicles had lower levels of mRNA for activin-A, than compared to primary follicles (p<0.05). There was no difference in levels of mRNA for activin-A between primordial and primary or secondary (p>0.05). Allied to this, there was no difference between COCs of small and large antral follicles (p>0.05). Moreover, granulosa and theca cells of large antral follicles showed higher levels of mRNA for activin-A than in small antral follicles (p<0.05). When comparing mRNA expression for activin-A between COCs from small and large antral follicles and their granulosa and theca cells, no difference in expression levels was observed (p>0.05). After in vitro culture of secondary follicles, the presence of FSH either alone or associated with activin-A or GDF-9 increased survival, follicular growth and antrum formation (p<0.05). The FSH increased mRNA for activin-A, while the follicles cultured with activin-A showed increased levels of mRNA for FSH-R (p<0.05). In addition, GDF-9 decreased mRNA expression for BMP -2 and -15 (p<0.05), but had no effect on expression of BMP -4, -6, and -7 (p>0.05). In conclusion, during the transition from primary to secondary follicles there is a reduction of mRNA for activin-A, whereas there is an increased expression of this factor during the growth of antral follicles. FSH, activin-A and GDF-9 stimulate growth of goat secondary follicles after 6-day culture. After follicle culture FSH controls the expression of activin-A, and the expression of FSH-R is regulated by activin-A. Furthermore, GDF-9 reduces the mRNA expression for BMP-2 and -15.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-12-05T12:12:19Z No. of bitstreams: 1 PDF - Jamesson de Macedo Andrade.pdf: 4828789 bytes, checksum: eabb6500a6b9b6696d06f824c8150ff7 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-12-06T19:17:12Z (GMT) No. of bitstreams: 1 PDF - Jamesson de Macedo Andrade.pdf: 4828789 bytes, checksum: eabb6500a6b9b6696d06f824c8150ff7 (MD5) / Made available in DSpace on 2016-12-06T19:17:12Z (GMT). No. of bitstreams: 1 PDF - Jamesson de Macedo Andrade.pdf: 4828789 bytes, checksum: eabb6500a6b9b6696d06f824c8150ff7 (MD5) Previous issue date: 2016-07-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Introduction: Oral squamous cell carcinoma (OSCC) in young individuals has increased in recent years with incidence ranged of 1.4% to 13.0% and the literature has suggested a more aggressive biological behavior that OSCC in older individuals. Immunoexpression of Activin A, Ki-67 and Bcl-2 were studied in various malignant neoplasms, although researches comparing the immunoexpression these markers in OSCC between young and older individuals are scarce. Objectives: To evaluate immunoexpression of activin A, Ki-67 and Bcl-2 in cases of tongue squamous cell carcinoma (TSCC) between young and older patients and verify the association of this immunoexpression with clinicopathological parameters (tumor size, node metastasis, distant metastasis and clinical stage) and histopathological grade of malignancy. Material and methods: The sample was composed for 60 cases of TSCC, diagnosed in two hospitals of reference in oncology in Paraíba state, Brazil. It was considered two groups: 30 cases of young (≤45y) and 30 cases of older (≥60y). Clinical parameters were obtained of medical records. For morphological analysis utilized the histopathological grade of malignancy, proposed by Bryne et al (1992). Immunohistochemical analysis was realized of quali- quantitative manner for polyclonal antibody Activin A and quantitative manner for antibodies Ki-67 and Bcl-2. Statistical analysis utilized Chi-square, Fisher’s exact, Mann Whitney and Spearman’s Correlation (P<0.05). Results: In regarding to clinical and morphological parameters between groups, there was significant difference to tumor size (P=0.024). In older patients, tumor size was associated to T1-T2. Although without significant difference (P>0.05) the older patients were predominantly diagnosed in earlier clinical stage (I/II) and young patients in later clinical stage (III/IV). In both groups, TSCC were classified as high grade of malignancy (P>0.05). The median of Activin A in TSCC was 55 (range, 7.5 to 112.5) in young patients and 65 (range, 40.0 to 90.0) in older patients (P=0.428). Significant difference in the immunoexpression of Activin A was observed in relation to clinical state (III/IV) in older patients (P=0.04). The median of immunoexpression of Ki-67 in TSCC was 46.9 (range, 29.9 to 56.3) in young patients and 34.8 (28.0 to 48.5) in older patients (P=0.085). Significant difference in the immunoexpression of Ki-67 was observed in relation to histological grade of malignancy in both groups, where in young patients was associated to high grade (P=0.039) and olderly patients was associated to low grade (P=0.047). The median of immunoexpression of Bcl-2 in TSCC was 8.85 (range, 3.97 to 16.62) in young patients and 13.3 (range, 7.47 to 25.55) in olderly patients (P=0.049). There was no significant difference was observed in immunoexpression of Bcl-2 in relation to clinical or morphological parameters, in either age groups (P>0.05). In addition, it was observed positive correlation between immunoexpression of Activin A and Bcl-2 in older patients (r=0.370, P=0.044). Conclusions: Based on these results, it is suggested that the difference in biological behavior of TSCC between young and old may be related to different pathogenesis. In young patients, it is suggested that the pathogenesis of TSCC is associated with increased cell proliferation, while in olderly patients, pathogenesis of TSCC is associated evasion of apoptosis, being regulated by activin A. / Introdução: O carcinoma de células escamosas oral (CCEO) em indivíduos jovens tem aumentado nos últimos anos, com incidência variando de 1,4% a 13%, e a literatura tem sugerido um comportamento biológico mais agressivo que o CCEO em indivíduos idosos. A imunoexpressão da Ativina A, Ki-67 e Bcl-2 tem sido estudada em vários processos neoplásicos malignos, embora pesquisas comparando a imunoexpressão desses marcadores em CCEO, entre indivíduos jovens e idosos, ainda são escassas. Objetivos: avaliar a imunoexpressão da Ativina A, Ki-67 e Bcl-2, em casos de carcinomas de células escamosas de língua (CCEL) imunoexpressão com os parâmetros clínicos (tamanho do tumor, metástase linfonodal, metástase à distância e estágio clínico) e grau histopatológico de malignidade. Material e métodos: A amostra foi composta por 60 casos de CCEL, diagnosticados em dois hospitais de entre pacientes jovens e idosos e verificar a associação desta referência em oncologia do estado da Paraíba, Brasil. Considerou-se dois grupos: jovens (≤45 anos, n=30) e idosos (≥60 anos, n=30). Os dados clínicos foram obtidos dos prontuários médicos e na análise morfológica utilizou-se o sistema de gradação histopatológico de malignidade (SGHM), proposto por Bryne et al. (1992). A análise imunoistoquímica foi realizada de forma quali-quantitativa para o anticorpo policlonal Ativina A e de forma quantitativa para os anticorpos monoclonais Ki-67 e Bcl-2. Para as análises estatísticas foram utilizados os testes de Qui-quadrado, exato de Fisher, Mann-Whitney e correlação de Spearman (p<0,05). Resultados: Em relação aos parâmetros clínicos e morfológicos entre os grupos, houve diferença significativa para o tamanho do tumor (p=0,024), em que nos pacientes idosos, o tamanho do tumor foi associado a T1-T2. Embora sem diferença significativa (p>0,05), os pacientes idosos foram predominantemente diagnosticados em estágios clínicos iniciais (I/II) e os pacientes jovens em estágios clínicos mais avançados (III/IV). Em ambos os grupos, o CCEL foi classificado como de alto grau de malignidade (p>0,05). A mediana da Ativina A em CCEL foi de 55 (7,5-112,5) em pacientes jovens e 65 (40,0-90,0) em pacientes idosos (p=0,428). Foi observada diferença significativa na imunoexpressão de Ativina A em relação ao estágio clínico (III/IV) em pacientes idosos (p=0,04). A mediana da imunoexpressão de Ki-67 em pacientes jovens com CCEL foi de 46,9 (29,9-56,3) e 34,8 (28,0-48,5) em pacientes idosos (p=0,085). Foi observada diferença significativa na imunoexpressão de Ki-67 em relação ao grau histopatológico de malignidade em ambos os grupos, onde em pacientes jovens foi associada ao um alto grau (p=0,039) e pacientes idosos ao baixo grau (p= 0,047). A mediana da imunoexpressão de Bcl-2 em CCEL foi 8,85 (3,97-16,62) em pacientes jovens e 13,3 (7,47-25,55) em pacientes idosos (p=0,049). Não foi observada diferença significativa, na imunoexpressão de Bcl-2 em relação aos parâmetros clínicos ou morfológicos, em ambos os grupos (p>0,05). Além disso, observou-se correlação positiva entre a imunoexpressão da Ativina A e Bcl-2 em pacientes idosos (r=0,370; p=0,044). Conclusões: Baseado nesses resultados, sugere-se que a diferença no comportamento biológico do CCEL entre jovens e idosos pode estar relacionada a patogenias distintas. Nos pacientes jovens, sugere-se que a patogenia do CCEL esteja associada a um maior índice de proliferação celular, enquanto que nos pacientes idosos, a patogenia do CCEL esteja associada a evasão da apoptose, sendo regulada pela ativina A.

京都大学 / 0048 / 新制・課程博士 / 博士(生命科学) / 甲第20521号 / 生博第363号 / 新制||生||48(附属図書館) / 京都大学大学院生命科学研究科統合生命科学専攻 / (主査)教授 西田 栄介, 教授 米原 伸, 教授 豊島 文子 / 学位規則第4条第1項該当 / Doctor of Philosophy in Life Sciences / Kyoto University / DFAM

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L’érythropoïèse est le processus de formation des globules rouges. L’anémie demeure à l’heure actuelle un problème de santé publique majeur. Par conséquent, une meilleure compréhension des mécanismes impliqués dans le contrôle de ce processus dans des conditions physiologiques et pathologiques, ainsi que l’établissement de stratégies thérapeutiques ciblées constituent un enjeu de recherche majeur. Le récepteur de la transferrine 1 (CD71/RTf1) est un élément essentiel de l'érythropoïèse, la majorité des travaux de recherche étant focalisés sur son rôle indéniable dans le métabolisme du fer. Cependant, de nouveaux ligands du RTf1 ont été découverts ouvrant de nouvelles perspectives relatives aux fonctionnalités de ce récepteur. Ayant démontré que le RTf1 fixait les immunoglobulines A1 (IgA1), nous nous sommes intéressés au rôle des IgA1 dans l’érythropoïèse. Nous montrons que le RTf1 lié aux polymères d'IgA1 (pIgA1) induit la croissance et une augmentation de la prolifération des érythroblastes en concentration sous-optimale d'érythropoïétine (Epo). De même, l'expression transgénique d’IgA1 humaine (souris alpha1-KI), ou le traitement de souris de type sauvage avec les pIgA1 permettent une récupération accélérée de l’anémie aiguë. L’engagement du RTf1 module la sensibilité à l'Epo, en diminuant le seuil d'activation cellulaire, et en induisant les voies de signalisation MAPK/ERK et phosphatidylinositol-3-kinase (PI3K/AKT). Ces données mettent en évidence un nouveau rôle du RTf1 en tant que régulateur positif de l'érythropoïèse. Parallèlement au RTf1, nous avons identifié un autre récepteur pouvant constituer une cible thérapeutique pour corriger une érythropoïèse inefficace : le récepteur de l’activine de type IIA (ActRIIA). Dans un modèle murin de Beta-thalassémie intermédiaire (Hbbth1/th1), résultant d'une déficience génétique de la chaîne Beta de la globine, nous montrons que l'administration d'une protéine de fusion constituée du domaine extracellulaire de l’ActRIIA lié à un fragment Fc d’IgG de souris (RAP-011), corrige l'anémie, augmente le taux d'hémoglobine et diminue la splénomégalie. Ce traitement favorise l’érythropoïèse splénique et diminue la saturation de la transferrine et l’hémolyse. Fait intéressant, des niveaux élevés de GDF11 (Growth Differentiation Factor 11) sont observés sur des coupes spléniques de souris thalassémiques ainsi que dans le sérum de patients thalassémiques. In vivo, l’inhibition de l’interaction GDF11/ActRIIa par le RAP-011 favorise l’apoptose des érythroblastes précoces par la voie Fas/FasLigand. Ces résultats suggèrent que l’activation constitutive des signaux GDF11/ActRIIA contribue à l’établissement d’une érythropoïèse inefficace caractéristique de la Beta-thalassémie. La neutralisation de cette signalisation inverse ce processus. En conclusion, nos travaux ouvrent de nouvelles perspectives dans la compréhension de l'hématopoïèse normale et pathologique, et pourraient conduire à envisager des traitements innovants pour l'anémie. / Anemia produced by a variety of underlying causes is the most common disorder of the blood, and remains a major global public health problem associated with a poor quality of life for many patients. Thus, better understanding the erythroid process in physiological and pathological conditions, and developing new strategies to boost erythropoiesis appear of great interest. Transferrin receptor 1 (CD71/TfR1) plays an essential role in erythropoiesis, and investigations of TfR1 functions have been focused on their undeniable role in iron metabolism. However, recent data demonstrate that TfR1 is a multi-ligand receptor that participates in a wide array of cellular functions. We have identified TfR1 as a receptor for A1 isotype immunoglobulins (IgA1). In this work, we show that pIgA1s are able through their interaction with the TfR1, to stimulate erythropoiesis by sensitizing erythroblasts to Epo. Likewise, transgenic expression of human IgA1 (Alpha1-KI mice) or treatment of wild-type mice with pIgA1 accelerated recovery from acute anemia. TfR1 engagement by pIgA1 increased cell sensitivity to Epo by inducing activation of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) signaling pathways. These findings unveiled a new role of TfR1 as a signaling competent molecule positively regulating erythropoiesis. In addition to TfR1, our work identifies another receptor as a putative target for correcting ineffective erythropoiesis: the activin receptor IIA (ActRIIA). Indeed, using a mouse model of Beta-thalassemia intermedia (Hbbth1/th1) resulting from a genetic deficiency of Beta-globin chain, we show that administration of a ligand trap (named RAP-011), consisting in a fusion protein between the extracellular domain of ActRIIA and the Fc fragment of a mouse IgG, improves anemia, increases total hemoglobin levels and decreases splenomegaly. In addition, targeting ActRIIa signaling corrects ineffective erythropoiesis in the spleen, reduces hemolysis and transferrin saturation. Interestingly, high levels of Growth Differentiation Factor 11 (GDF11) are detected in spleen sections from Beta-thalassemic mice, as well as in sera from thalassemic patients. In addition, the inactivation of GDF11 promotes terminal erythroblast differentiation. Finally, blockade of the GDF11/ActRIIa signaling, promotes premature apoptosis of early erythroblasts through induction of Fas/FasLigand pathway. Therefore, these results first suggest that constitutive GDF11/ActRIIa signaling pathway may promote ineffective erythropoiesis in Beta-thalassemia intermedia, and secondly, support the use of ActRIIa traps for the treatment of chronic anemia and ineffective erythropoiesis. Altogether, these results open new perspectives in the understanding of normal and pathological hematopoiesis and lead to propose innovative treatments for anemia.

Lin Sze-Wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 111-127). / Abstracts in English and Chinese. / Abstract (in English) --- p.i / Abstract (in Chinese) --- p.iii / Acknowledgements --- p.iv / Table of Contents --- p.v / Abbreviations --- p.x / Scientific Names --- p.xii / Chapter CHAPTER 1 --- GENERAL INTRODUCTION --- p.1 / Chapter 1.1 --- Gonadotropins --- p.1 / Chapter 1.1.1 --- Structure --- p.1 / Chapter 1.1.2 --- Function --- p.1 / Chapter 1.1.3 --- Regulation --- p.2 / Chapter 1.1.3.1 --- Gonadotropin-releasing hormone (GnRH) --- p.3 / Chapter 1.1.3.2 --- Dopamine --- p.4 / Chapter 1.1.3.3 --- Sex steroids --- p.5 / Chapter 1.1.3.3.1 --- Functions --- p.5 / Chapter 1.1.3.3.2 --- Working mechanism´ؤEstrogen signaling pathway --- p.7 / Chapter 1.1.3.4 --- Gonadal peptides --- p.9 / Chapter 1.1.3.4.1 --- Functions --- p.9 / Chapter 1.1.3.4.2 --- Working mechanism一Activin signaling pathway --- p.11 / Chapter 1.2 --- Transcriptional regulation of pituitary gonadotropin subunit genes at the promoter level --- p.13 / Chapter 1.2.1 --- Transcriptional regulation of mammalian glycoprotein a subunits --- p.13 / Chapter 1.2.1.1 --- GnRH --- p.14 / Chapter 1.2.1.2 --- Activin --- p.15 / Chapter 1.2.1.3 --- Steroids --- p.15 / Chapter 1.2.2 --- Transcriptional regulation of mammalian FSHβ and LHβ subunits --- p.16 / Chapter 1.2.2.1 --- Regulation of LHβ expression by GnRH --- p.17 / Chapter 1.2.2.1.1 --- Roles of SP-1 binding sites on LHβ promoter --- p.17 / Chapter 1.2.2.1.2 --- Effect of SF-1 on LHp expression --- p.17 / Chapter 1.2.2.1.3 --- Effect of Egr-1 on LHp expression --- p.18 / Chapter 1.2.2.1.4 --- "Synergistic effect ofSP-1, SF-1 and Egr-1 on LHp expression." --- p.18 / Chapter 1.2.2.1.5 --- Effect of Pitx-1 on LHβ expression --- p.19 / Chapter 1.2.2.1.6 --- "Effect of SF-1, Egr-1 and Pitx-1 on LHβ expression of other mammalian counterparts" --- p.19 / Chapter 1.2.2.1.7 --- Effect of other transcription factors on mammalian LHβ expression --- p.19 / Chapter 1.2.2.2 --- Regulation of LHβ expression by steroids and activin --- p.20 / Chapter 1.2.2.3 --- Regulation of FSHβ expression by activin and GnRH --- p.20 / Chapter 1.2.2.4 --- Regulation of FSHβ expression by steroids --- p.21 / Chapter 1.2.2.5 --- Regulation of FSHβ expression by other transcription factors --- p.22 / Chapter 1.2.3 --- Transcriptional regulation of fish FSHβ and LHβ subunits --- p.22 / Chapter 1.3 --- The project objectives and long-term significance --- p.24 / Chapter CHAPTER 2 --- CLONING OF ZEBRAFISH FSHB AND LHB PROMOTERS. --- p.26 / Chapter 2.1 --- Introduction --- p.26 / Chapter 2.2 --- Materials and Methods --- p.27 / Chapter 2.2.1 --- Chemicals --- p.27 / Chapter 2.2.2 --- Animals --- p.27 / Chapter 2.2.3 --- Isolation of genomic DNA --- p.28 / Chapter 2.2.4 --- Cloning of promoters of zebrafish FSHβ and LHβ from the genomic DNA --- p.28 / Chapter 2.2.5 --- Construction of the reporter plasmids containing zebrafish FSHβ and LHβ promoters --- p.30 / Chapter 2.2.6 --- Cell culture and transient transfection --- p.31 / Chapter 2.2.7 --- SEAP reporter gene assay --- p.32 / Chapter 2.2.8 --- β-galactosidase reporter gene assay --- p.32 / Chapter 2.2.9 --- Data analysis --- p.33 / Chapter 2.3 --- Results --- p.33 / Chapter 2.3.1 --- Cloning of zebrafish FSHβ and LHβ promoters --- p.33 / Chapter 2.3.2 --- Sequence characterization of zebrafish FSHβ and LHβ promoters --- p.34 / Chapter 2.3.3 --- Basal FSHp and LHβ promoter activities in LβT2 cells --- p.35 / Chapter 2.4 --- Discussion --- p.36 / Chapter CHAPTER 3 --- ROLES OF ACTIVIN/SMADS AND ESTROGEN/ERS IN THE REGULATION OF ZEBRAFISH FSHB AND LHB PROMOTER ACTIVITY --- p.51 / Chapter 3.1 --- Introduction --- p.52 / Chapter 3.2 --- Materials and Methods --- p.56 / Chapter 3.2.1 --- Chemicals --- p.56 / Chapter 3.2.2 --- Animals --- p.56 / Chapter 3.2.3 --- Isolation of total RNA --- p.57 / Chapter 3.2.4 --- Rapid amplification of full-length cDNA (RACE) --- p.57 / Chapter 3.2.5 --- Construction of expression plasmids --- p.57 / Chapter 3.2.6 --- cell culture and transient transfection --- p.59 / Chapter 3.2.7 --- SEAP reporter gene assay --- p.59 / Chapter 3.2.8 --- p-galactosidase reporter gene assay --- p.59 / Chapter 3.2.9 --- Data analysis --- p.59 / Chapter 3.3 --- Results --- p.60 / Chapter 3.3.1 --- Cloning and sequence characterization of zebrafish Smad 4 (zfSmad 4) --- p.60 / Chapter 3.3.2 --- Smads regulate FSHβ transcription in LβT2 cells --- p.61 / Chapter 3.3.3 --- Smads regulate LHβ transcription in LPβT2 cells --- p.61 / Chapter 3.3.4 --- Functionality of the two forms of Smad 4 cloned --- p.62 / Chapter 3.3.5 --- Estrogen and ERs regulate zJFSHβ transcription in LβT2 cells --- p.63 / Chapter 3.3.6 --- Estrogen and ERs regulate zfLHβ transcription in LβT2 cells --- p.63 / Chapter 3.4 --- Discussion --- p.64 / Chapter CHAPTER 4 --- PROMOTER ANALYSIS FOR SMAD RESPONSIVE ELEMENT AND ESTROGEN RESPONSIVE ELEMENT IN ZEBRAFISH FSHB AND LHB PROMOTERS --- p.82 / Chapter 4.1 --- Introduction --- p.83 / Chapter 4.2 --- Materials and Methods --- p.85 / Chapter 4.2.1 --- Chemicals and animals --- p.85 / Chapter 4.2.2 --- Construction of SEAP reporter plasmids containing different lengths of zfFSHβ promoter --- p.85 / Chapter 4.2.3 --- Construction of SEAP reporter plasmids containing different lengths of zfLHβ promoter --- p.85 / Chapter 4.2.4 --- Site-directed mutagenesis --- p.86 / Chapter 4.2.5 --- cell culture and transient transfection --- p.87 / Chapter 4.2.6 --- SEAP reporter gene assay --- p.87 / Chapter 4.2.7 --- P-galactosidase reporter gene assay --- p.87 / Chapter 4.2.8 --- Data analysis --- p.88 / Chapter 4.3 --- Results --- p.88 / Chapter 4.3.1 --- Localization of Smad-responsive element (SRE) on zfFSHβ promoter --- p.88 / Chapter 4.3.2 --- Localization of estrogen-responsive element (ERE) on zfLHβ promoter --- p.89 / Chapter 4.3.3 --- Localization of estrogen-responsive element (ERE) on zfFSHβ promoter --- p.90 / Chapter 4.3.4 --- Confirmation of SRE by site-directed mutagenesis --- p.91 / Chapter 4.3.5 --- Confirmation of ERE by site-directed mutagenesis --- p.92 / Chapter 4.4 --- Discussion --- p.92 / Chapter CHAPTER 5 --- GENERAL DISCUSSION --- p.106 / Chapter 5.1 --- Overview --- p.106 / Chapter 5.2 --- Contribution of the present research --- p.107 / Chapter 5.3 --- Future research direction --- p.108 / REFERENCE: --- p.111

<p>Thyroid growth and function is partly regulated by growth factors binding to receptors on the cell surface. In the present thesis, the transforming growth factor-β (TGF-β) superfamily members have been studied for their role in regulation of growth and differentiation of both normal and neoplastic thyroid epithelial cells.</p><p>TGF-β1 is a negative regulator of thyrocyte growth and function. However, the importance of other TGF-β superfamily members has not been fully investigated. TGF-β1, activin A, bone morphogenetic protein (BMP)-7 and their receptors were found to be expressed in porcine thyrocytes. In addition to TGF-β1, activin A was also found to be a negative regulator of thyroid growth and function, and both stimulated phosphorylation and nuclear translocation of Smad proteins. Furthermore, TGF-β1 and epidermal growth factor (EGF) demonstrated a synergistic negative effect on thyrocyte differentiation. Simultaneous addition of the two factors resulted in a loss of the transepithelial resistance and expression of the epithelial marker E-cadherin. This was followed by a transient expression of N-cadherin.</p><p>Despite the extremely malignant character of anaplastic thyroid carcinoma (ATC) tumor cells, established cell lines are still responsive to TGF-β1. A majority of the cell lines were also found to be growth inhibited by BMP-7. BMP-7 induced cell cycle arrest of the ATC cell line HTh 74 in a dose- and cell density-dependent manner. This was associated with upregulation of p21^CIP1 and p27^KIP1, decreased cyclin-dependent kinase (Cdk) activity and hypophosphorylation of the retinoblastoma protein (pRb). TGF-β1, and to some extent also BMP-7, induced the expression of N-cadherin and matrix metalloproteinase (MMP)-2 and -9. Stimulation of HTh 74 cells with TGF-β1 increased the migration through a reconstituted basement membrane indicating an increased invasive phenotype of the cells.</p><p>Taken together, these data show that TGF-β superfamily members not only affect growth and function of normal thyroid follicle cells but may also, in combination with EGF, play a role in cell dedifferentiation. This study additionally suggests that the TGF-β superfamily members may be important for the invasive properties of ATC cells.</p>

Thyroid growth and function is partly regulated by growth factors binding to receptors on the cell surface. In the present thesis, the transforming growth factor-β (TGF-β) superfamily members have been studied for their role in regulation of growth and differentiation of both normal and neoplastic thyroid epithelial cells. TGF-β1 is a negative regulator of thyrocyte growth and function. However, the importance of other TGF-β superfamily members has not been fully investigated. TGF-β1, activin A, bone morphogenetic protein (BMP)-7 and their receptors were found to be expressed in porcine thyrocytes. In addition to TGF-β1, activin A was also found to be a negative regulator of thyroid growth and function, and both stimulated phosphorylation and nuclear translocation of Smad proteins. Furthermore, TGF-β1 and epidermal growth factor (EGF) demonstrated a synergistic negative effect on thyrocyte differentiation. Simultaneous addition of the two factors resulted in a loss of the transepithelial resistance and expression of the epithelial marker E-cadherin. This was followed by a transient expression of N-cadherin. Despite the extremely malignant character of anaplastic thyroid carcinoma (ATC) tumor cells, established cell lines are still responsive to TGF-β1. A majority of the cell lines were also found to be growth inhibited by BMP-7. BMP-7 induced cell cycle arrest of the ATC cell line HTh 74 in a dose- and cell density-dependent manner. This was associated with upregulation of p21CIP1 and p27KIP1, decreased cyclin-dependent kinase (Cdk) activity and hypophosphorylation of the retinoblastoma protein (pRb). TGF-β1, and to some extent also BMP-7, induced the expression of N-cadherin and matrix metalloproteinase (MMP)-2 and -9. Stimulation of HTh 74 cells with TGF-β1 increased the migration through a reconstituted basement membrane indicating an increased invasive phenotype of the cells. Taken together, these data show that TGF-β superfamily members not only affect growth and function of normal thyroid follicle cells but may also, in combination with EGF, play a role in cell dedifferentiation. This study additionally suggests that the TGF-β superfamily members may be important for the invasive properties of ATC cells.

Made available in DSpace on 2016-06-02T20:19:18Z (GMT). No. of bitstreams: 1 4384.pdf: 6022457 bytes, checksum: 1327718b29745e1447375271aa448490 (MD5) Previous issue date: 2012-04-10 / Universidade Federal de Sao Carlos / Nonalcoholic Fatty Liver disease (NAFLD) is characterized by fat accumulation in the liver and associated with obesity and insulin resistance. Activin A is a member of the transforming growth factor (TGF)-&#946; superfamily which inhibits hepatocyte growth and induces apoptosis. Follistatin is a glycoprotein which antagonizes the biological actions of activin. Exercise is an important therapeutic strategy to decrease the metabolic effects of obesity. In this study, we evaluated the pattern of Activin A and follistatin liver expression in obese rats submitted to swimming exercise. Adult male Wistar rats were allowed free access to standard rodent chow (control group, C) or HF diet (58% Kcal from fat, high-fat group, HF) during 12 weeks. Glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed at 12 weeks. After 12 weeks, C and HF rats were randomly assigned to a swimming training group (C-Ex and HF-Ex) or a sedentary group (C-Sed and HF-Sed). C-Ex and HF-Ex swam for 45 minutes at 0900h and 1700h, 5 day week-1, for 4 weeks. After this period, rats were submitted again to GTT and then killed by decapitation. Plasma was collected for liver enzymes, alanine transaminase (ALT), aspartate transaminase (AST) and gammaglutamyl transaminase (GGT) determination. Liver was dissected and immediately frozen in liquid nitrogen and stored at -700 C for subsequent analysis. Actvin &#946;A subunit and follistatin mRNA was quantified by real time RT-PCR. HF developed insulin resistance according to GTT and ITT tests. ALT levels were significantly higher in HF-Sed than in C-Sed and significantly lower in HF-Ex than in HF-Sed. AST and GGT did not vary among the groups. Actvin &#946;A subunit mRNA was significantly higher in HF-Ex than in HF-Sed. Follistatin mRNA was significantly lower in C-Ex and HF-Ex compared to C-Sed and HF-Sed, respectively. There was no evidence of steatosis or inflammation (grade 0) in C. In contrast, in HF the severity of steatosis varied from grade 1 to grade 3. This was not associated with inflammation or fibrosis. After the training period, HF-Ex showed improvement in the extent of liver parenchyma damage, the severity of steatosis varying from grade 0 to grade 1. These data suggest that exercise may reduce the deleterious effects of high-fat diet on liver and the local expression of activin-follistatin may be involved. / A doença hepática gordurosa não alcoólica (DHGNA) é caracterizada pelo acúmulo de gordura no fígado e está associada à obesidade e à resistência insulínica. A activina A, membro da superfamília do fator de crescimento e transformação &#946; (TGF-&#946;), inibe o crescimento de hepatócitos e induz a apoptose. A folistatina é uma glicoproteína que antagoniza as ações biológicas da activina. O exercício é uma importante ferramenta terapêutica na diminuição dos efeitos metabólicos da obesidade. Neste estudo, foi avaliado o padrão de expressão de activina A e folistatina no fígado de ratos obesos submetidos ao exercício de natação. Ratos Wistar, machos e adultos tiveram acesso livre à dieta padrão (grupo controle, C) ou dieta hiperlipídica (58% Kcal de gordura, grupo dieta hiperlipídica, DH) durante 12 semanas. O teste de tolerância à glicose (TTG) e o teste de tolerância à insulina (TTI) foram realizados antes e após 3, 4, 8 e 12 semanas. Após 12 semanas, os animais C e DH foram distribuídos aleatoriamente em grupos exercício (CE e DHE) ou grupos sedentários (CS e DHS). Os grupos CE e DHE nadaram por 45 minutos às 9:00h e 17:00h, 5 vezes por semana, durante 4 semanas. Após este período, os animais foram submetidos novamente ao TTG e foram sacrificados por decapitação. O plasma foi coletado para analisar as enzimas hepáticas alanina transaminase (ALT), aspartato transaminase (AST) e gama glutamil transferase (GGT). O fígado foi dissecado e imediatamente congelado em nitrogênio líquido e armazenado a -80ºC para posterior análise. O RNAm da subunidade &#946;A de activina e folistatina foi quantificado por PCR-RT em tempo real. O grupo DH desenvolveu resistência à insulina de acordo com os testes TTG e TTI. Os níveis de ALT foram significativamente maiores no grupo DHS comparados com o grupo CS e significativamente menores no grupo DHE comparados com o grupo DHS. Os níveis de AST e GGT não variaram entre os grupos. A expressão da subunidade &#946;A de activina foi significativamente maior no grupo DHE comparada com o grupo DHS. A expressão de folistatina foi significativamente menor nos grupos CE e DHE comparado aos grupos CS e DHS, respectivamente. Não houve evidências de esteatose ou inflamação (grau 0) no grupo C. Porém, no grupo DH a severidade da esteatose variou do grau 1 ao grau 3, mas não foi associada com inflamação ou fibrose. Após o período de treinamento, o grupo DHE apresentou melhora na extensão da lesão do parênquima hepático, com severidade da esteatose variando do grau 0 ao grau 1. Estes dados sugerem que o exercício reduziu os efeitos deletérios da dieta hiperlipídica no fígado e a expressão local de activina-folistatina pode está envolvida.