Fully grown oocytes' of the African clawed frog, Xenopus laevis, are arrested at the diplotene stage of meiotic prophase I, which resembles the G2 phase of the mitotic cell cycle. Re-entry into the meiotic divisions is initiated by hormonal signaling normally provided by progesterone. Progesterone signaling leads to the activation of maturation promoting factor (MPF), a heterodimer consisting of the protein kinase cdk1 and cyclin B1; this complex promotes the oocyte's entry into M phase of meiosis I. A crucial event required for MPF activation is cytoplasmic polyadenylation element (CPE)-mediated translation of specific dormant mRNAs such as c-mos and cyclin B1. The CPE, which resides in mRNA 3' untranslated region (UTR), is bound by the CPE binding protein (CPEB), which in turn is bound by Maskin. Maskin is bound to the 5' cap binding protein eIF4E. This type of closed-loop mRNA structure inhibits the recruitment and assembly of the translation initiation complex at the 5'UTR of CPE containing mRNAs. To alleviate this inhibition, CPEB undergoes phosphorylation on S174 by the serine/threonine kinase Aurora A. Phosphorylated CPEB promotes the recruitment of specific polyadenylation factors leading to the polyadenylation of the dormant mRNA, resulting in the disassociation of Maskin from eIF4E. eIF4E is subsequently bound by translation initiation factors leading to mRNA assembly into polysomes and synthesis of the encoded protein. Insulin signaling has also been shown to induce oocyte maturation. However, this signaling cascade uniquely requires the activation of two upstream components, PI3 kinase and PKC zeta. In this thesis, I show that insulin induced oocyte maturation requires the same CPE-mediated mRNA translation mechanism as had been described for progesterone signaling. I also show that Aurora A kinase activation and S174 phosphorylation play an essential role in insulin-induced CPE-mediated mRNA translation. Interestingly, inhibition of PI3 kinase and PKC zeta inhibits CPE-mediated polyadenylation only in the insulin-signaling pathway; the progesterone pathway is unaffected. These results clearly indicate that different upstream signaling components control CPE-mediated translation between progesterone and insulin signaling cascades. However, both pathways are antagonized by over expressed GSK-3, leading to inhibition of oocyte maturation. Furthermore, I found that GSK-3 inhibits Aurora A kinase activity by directly phosphorylating Aurora A on serine 290/291, promoting an inhibitory autophosphorylation event on serine 349. The importance of a GSK-3/Aurora A interaction is underscored by the finding that GSK-3, Axin, and Aurora A reside in a complex in immature oocytes. During progesterone or insulin signaling, GSK-3 dissociates from Aurora A allowing Aurora A to become active, leading to CPEB phosphorylation, CPE-mediated mRNA translation and oocyte maturation.

De två läkemedel som administreras vid medicinsk abort i Sverige idag består av de aktiva substanserna mifepriston respektive misoprostol. Behandlingskuren bygger på effekter hos de endogena ämnena progesteron och prostaglandiner. I denna studie beskrivs fysiologiska processer under graviditeten med avseende på progesteron och prostaglandiner samt vid medicinsk abort med avseende på mifepriston och misoprostol. Valet av fokus på fysiologiska processer speglar biologilärarens didaktiska uppgift i att undervisa om hur människokroppen fungerar och dess interaktion med läkemedel. Slutligen presenteras och diskuteras även möjligheter och svårigheter med undervisning om abort inom ramen för högstadie- och gymnasieskolans biologiundervisning. / The drugs administrated to cause medical abortion consist of one tablet with the active substance mifepristone and one with the active substance misoprostol. The regime is based on effects of the endogenic substances progesterone and prostaglandins. In this study, physiological processes in pregnancy regarding progesterone and prostaglandins are described, as well as the physiological processes in medical abortion with respect to mifepristone and misoprostol. The focus on physiological processes relates to the mission of the biology teacher to explain how the human body works and interacts with medical drugs. Finally, opportunities and difficulties with instructions on abortion in secondary and upper secondary school biology are presented and discussed.

<p> The age at which a juvenile female reaches sexual maturity can be modulated by a variety of environmental and social factors. Experiments described in this thesis were designed to enhance the current understanding of the relationships among three variables that influence the onset of sexual maturation in female mice (Mus musculus), including: [1] exposure to dietary phytoestrogens during development, [2] variations in prenatal androgens, and [3] the presence or absence of genetically-unrelated males after weaning. For the first time, age at onset of male-induced female puberty was investigated using non-invasive behavioural and fertility measures. Through enzyme immunoassay procedures, daily output of urinary creatinine, 17P-estradiol, and progesterone was profiled in developing females that were either isolated or exposed to adult males. Uterine and ovarian tissue was also measured in such females, and male exposure was observed to increase reproductive tissue mass and was influenced by prior androgen exposure in interaction with diet and male presence. Male-exposed females fed a diet containing phytoestrogens immediately became sexually receptive when housed directly with males, and they conceived earlier than females in other conditions. Females with longer anogenital distance, which reflects higher in utero androgen exposure, displayed more escape attempts and aggressive posturing in the direct presence of males, especially when they had been housed near males and fed the phytoestrogen-containing diet. Urinary 17P-estradiol was substantially reduced in females raised on the phytoestrogenfree diet. Urinary output of progesterone was not strongly influenced by diet. Maleexposed females ' output of progesterone and 17P-estradiol was more dynamic in comparison to that of isolated females. The size of this effect depended on diet, prior androgen exposure, and whether urinary steroid measures were adjusted by urinary creatinine. Urinary creatinine was elevated by the low phytoestrogen diet and reduced by male exposure. These data suggest that dietary phytoestrogens and in utero androgen exposure interact with presence or absence of males in determining the age at onset of sexual maturity in developing females. </p> <p> A final experiment was designed to examine two components of adult male urine, preputial gland emissions and unconjugated estrogens, that have been posited to act on females to advance reproductive maturation. Intact and preputialectomized males were compared in their output of urinary creatinine, 17~-estradiol, and testosterone, and in their influence on reproductive tissue in juvenile females. Lack of preputial glands did not hinder the capacity of males to induce uterine and ovarian growth in females. Male urinary creatinine was reduced by exposure to juvenile females. Creatinine-adjusted 17~estradiol and testosterone were greater in female-exposed males, regardless of whether the preputial glands were present. Based on these findings and those reported elsewhere, it is probable that male excreted urinary steroids are important in regulating reproductive changes in developing females exposed to males. </p> / Thesis / Doctor of Philosophy (PhD)

No description available.

L'utérus est un organe hautement dynamique, qui subit des changements morphologiques durant le cycle œstral sous l'influence des hormones sexuelles. Ces adaptations sont essentielles à l’homéostasie utérine et résultent d’une régulation minutieuse de la prolifération, de la différenciation et de la survie cellulaire par de nombreuses voies de signalisation. Nous avons émis l'hypothèse que la voie Hippo est impliquée dans l'homéostasie utérine chez l’espèce bovine, et nous avons tenté de déterminer les variations de ses constituants. Des biopsies de l'endomètre et des échantillons de sang ont été obtenus aux jours 0, 3 et 10 du cycle chez 14 vaches. Les concentrations sanguines de progestérone et d’œstrogène ont confirmé la progression du cycle œstral chez cinq vaches. Des analyses immunohistochimiques, Western Blot et RT-PCR ont été réalisées sur les biopsies afin d’évaluer la variation des composantes de la voie Hippo et de ses gènes cibles. Nous avons démontré la présence de YAP et de TAZ dans l'endomètre bovin à tous les moments du cycle œstral. Elles présentaient une expression cytoplasmique dans l'épithélium glandulaire, et présentaient une expression nucléaire dans le stroma à J0 et J10 et dans l'épithélium luminal à J3. Nous avons également noté une tendance à l'augmentation des concentrations de la forme phosphorylée de YAP au jour 3 du cycle œstral par rapport aux jours 0 et 10. Cette augmentation a été corrélée à une diminution de l'expression du gène CTGF au jour 3 par rapport aux autres jours du cycle œstral. En conclusion, nous avons démontré que la voie Hippo est exprimée différentiellement dans l'utérus bovin au cours du cycle œstral. / The uterus is a highly dynamic organ that changes morphologically under the influence of sexual hormones during the estrous cycle. These adaptations are essential for the proper function of the uterus and are due to the careful regulation of cell proliferation, differentiation, and apoptosis by numerous signaling pathways. We hypothesized that the Hippo pathway is implicated in uterine homeostasis in cattle, and we aimed to determine the variation of its canonical constituents during the bovine cycle. Endometrial biopsies and blood samples were obtained on days 0, 3, and 10 of the cycle in 14 cows. Progesterone and estrogens blood concentrations were measured and confirmed the status of the oestrus cycle in five cows. Immunohistochemistry, western blot, and RT-PCR were then performed on their endometrial biopsies to evaluate the Hippo components and targeted genes. Our results showed the presence of YAP and TAZ in the bovine endometrium at all time point. Both proteins displayed cytoplasmic expression in the glandular epithelium while exhibiting nuclear expression in the stroma on D0 and D10 and in the luminal epithelium on D3. We also noted a tendency for an increased amount of phosphorylated YAP during day 3 of the estrous cycle compared to days 0 and 10. It was correlated with a decreased expression of CTGF (Hippo target gene) on day 3 compared to the other day of the cycle. In conclusion, we can confirm that Hippo is differentially expressed in the bovine uterus during the estrous cycle.

El gen humano 11&#61538;-HSD2 es un modelo para investigar la contribución de los efectos de los receptores de esteroides en células de cáncer de mama. El análisis del promotor mostró que la región distal está implicada en la mayor parte de la activación dependiente de hormona. En respuesta a hormona, STAT5A se recluta a la región distal y PR a las regiones distal y proximal del promotor. El reclutamiento de PR se debe a dos mecanismos diferentes, la unión directa de PR a la región proximal, y la implicación vía JAK/STAT en el reclutamiento a la región distal. La inducción del gen 11&#61538;-HSD2 por hormonas disminuye parcialmente por inhibidores de MAPK y PI3K/Akt y totalmente por inhibidores de JAK/STAT. Así, los efectos citoplasmáticos del PR están implicados en la inducción del gen progesterona. La forma activa de la ARN-polimerasa II es reclutada por la inducción con hormonas a la región distal del promotor 11&#61538;-HSD2 y la región distal tiene respuesta a hormonas por sí misma, indicando que la inducción del gen por hormonas empieza antes del sitio de inicio de transcripción descrito previamente. / The human 11&#61538;-HSD2 gene is a model to investigate the contribution of steroid hormone receptors effects on a progesterone responsive promoter in breast cancer cells. Deletion analysis of the 11&#61538;-HSD2 promoter showed that the distal region is involved in most of the hormone-dependent activation. ChIP showed hormone-dependent STAT5A-recruitment to the distal region and PR-recruitment to the distal and proximal promoter regions. Results suggest two different mechanisms of hormone-induced PR-recruitment, since cells stably expressing PR containing a mutated DNA-binding domain have affected hormone-dependent PR-recruitment to proximal promoter, and JAK/STAT pathway inhibition blocks PR-recruitment to distal promoter. Hormone-stimulated 11&#61538;-HSD2 gene-expression was partially decreased by MAPK and PI3K/AKT pathway inhibitors and totally blocked by JAK/STAT pathways inhibitors, indicating that cytoplasmic PR effects involvement in progestin-induced 11&#61538;-HSD2 expression. Importantly, upon hormone induction active RNA-polymerase II is recruited from the 11&#61538;-HSD2 distal promoter region and the distal minimal promoter has hormone-responsiveness by itself, suggesting that progesterone-dependent 11&#61538;-HSD2 expression starts upstream the previously characterized transcription start site.

Made available in DSpace on 2015-07-22T20:50:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-26. Added 1 bitstream(s) on 2015-08-11T03:25:58Z : No. of bitstreams: 1 Publico-11853.pdf: 1847638 bytes, checksum: 58d741297f37fd108b68cf301ea6653b (MD5) / Objetivo: Avaliar a presença do polimorfismo genético do receptor da progesterona (PROGINS) bem como as variáveis clínicas e epidemiológicas de risco para câncer de endométrio em mulheres com pólipos endometriais na pós-menopausa. Casuística e Métodos: Comparou-se em estudo caso-controle 154 mulheres menopausadas com pólipos endometriais benignos e 400 controles normais na pós-menopausa, quanto à presença do PROGINS, por meio da Reação em Cadeia da Polimerase (PCR). O grupo de pólipos endometriais foi comparado a 118 pacientes do grupo controle no tocante às variáveis clínicas e epidemiológicas de risco para câncer de endométrio. Estas variáveis foram também comparadas entre os pólipos benignos e malignos. Resultados: A comparação entre o grupo de pólipos benignos e o grupo controle mostrou significância estatística (p<0,05) para as varáveis: idade (média de 61,7 x 57,5 anos), raça não-branca (44,8% x 22,9%), anos da menopausa (média de 12,9 x 9,2 anos), paridade (média de 4,5 x 3,4 filhos), uso de tamoxifeno (5,2% x 0%), hipertensão arterial (54,5% x 29,7%) e antecedente de câncer de mama (10,4% x 0,8%) respectivamente. Após o ajuste para a idade, permaneceram com significância estatística, apenas a paridade (OR=1,13), a hipertensão arterial (OR=2,19) e o antecedente de câncer de mama (OR=14,44). Seis casos (3,75%), foram diagnosticados como pólipos malignos, nestes casos, sangramento na pós-menopausa e o tamanho grande do pólipo estiveram sempre presentes, enquando que nos pólipos benignos esta frequência foi de 23,4% para sangramento e 54,5% para pólipo grande. A hipertensão arterial foi bem mais frequente no grupo de pólipos malignos, 83,3% x 54,5% nos pólipos benignos. Não houve diferença estatisticamente significante entre os grupos quanto à presença do PROGINS, sendo no grupo de pólipos benignos a distribuição entre homozigoto selvagem, heterozigoto e homozigoto mutado de 79,9%, 19,5% e 0,6% respectivamente. No grupo controle (N=400) esta distribuição foi de 78,8%, 20,8% e 0,5% respectivamente. Conclusões: A presença do PROGINS não mostrou associação significativa com pólipos endometriais. As variáveis epidemiológicas significantemente associadas à presença de pólipos endometriais, após o ajuste para idade, foram a paridade, hipertensão arterial e o antecedente de câncer de mama (implícito o uso de tamoxifeno), além da idade mais avançada. Em nosso estudo, pólipos endometriais malignos estiveram sempre associados à presença de sangramento na pós-menopausa e tamanho grande do pólipo, sendo a hipertensão arterial achado bastante frequente. / Purpose: To evaluate the genetic polymorphism of the progesterone receptor (PROGINS), as well as clinical and epidemiological risk factors for endometrial cancer in postmenopausal women with endometrial polyps. Methods: A case control study was designed with 154 postmenopausal women with endometrial polyps, compared to a normal control group of 400 postmenopausal women. The genotyping of PROGINS polymorphism was determined by polymerase chain reaction. The group of polyps was compared to 118 normal postmenopausal controls regarding clinical and epidemiological variables. These variables were also compared between benign and malignant endometrial polyps. Results: The epidemiological variables among the group of endometrial polyps and normal control, showed statistical significance (p<0,05) for age: media of 61,7 and 57,5 years, ethnicity non-white 44,8% and 22,9%, time since menopause media of 12,9 and 9,2 years, parity media of 4,5 and 3,4 sons, tamoxifen use 5,2% and 0%, hypertension 54,5% and 29,7% and history of breast cancer 10,4% and 0,8% respectively. After age adjust, statistical significance, remained only for parity (OR=1,13), hypertension (OR=2,19) and history of breast cancer (OR=14,44). Postmenopausal bleeding and large polyps were present in all cases of malignancy. Hypertension was also very frequent in malignant polyps (83,3% and 54,5% respectively). The presence of PROGINS had no statistical significance between the group of polyps and the normal control (N=400). The presence of wild homozygosis genotype, heterozygosis and mutant homozygosis was 79,9%, 19,5% and 0,6% respectively for the polyp group, and 78,8%, 20,8% and 0,5% for the control group (p=0,208). Conclusions: There was no significant association between the presence of PROGINS and endometrial polyps. After age adjust, epidemiological variables significantly associated to endometrial polyps were elderly age, parity, hypertension, and history of breast cancer (implicit tamoxifen use). Malignant polyps in this study were always associated to postmenopausal bleeding, large polyps and frequently associated to hypertension. / TEDE / BV UNIFESP: Teses e dissertações

La multichimiorésistance est caractérisée par une résistance simultanée à des agents chimiothérapeutiques de structures diverses, induite notamment par l’efflux des substances actives hors des cellules. Les transporteurs ABC (ATP-Binding Cassette) sont des protéines transmembranaires impliquées dans cet efflux et qui participent à l’échec du traitement de certains cancers. Par ailleurs, ce mécanisme d’efflux a également été évoqué dans le cadre de la résistance de certains microorganismes aux antimicrobiens. Dans cette étude, nous avons conçu et synthétisé des dérivés susceptibles d’inhiber certains transporteurs ABC, en particulier, la glycoprotéine-P (Pgp) impliquée dans la multichimiorésistance des tumeurs humaines, et CpABC3, rencontré chez le parasite Cryptosporidium parvum. Dans un premier temps, nous avons synthétisé trois dérivés de type 4-alkyl-imidazo[4,5-b]pyridin-7-one, hétérocycles destinés à se fixer sur le site à ATP des transporteurs ABC. L’activité de ces composés a été évaluée vis-à-vis d’un fragment recombinant (H6-NBD1) de CpABC3, et un de ceux-ci a montré une liaison (faible) à ce fragment. Nous avons ensuite préparé dix-sept dérivés bivalents susceptibles d’inhiber la Pgp, constitués d’une molécule d’adénine (ciblant le site à ATP) reliée à la progestérone (ciblant le site aux stéroïdes) par un bras de géométrie variable. Ces dérivés ont été testés sur des lignées cellulaires K562/R7 surexprimant la Pgp, et un de ceux-ci a montré une activité supérieure à celle de la progestérone. Enfin, nous avons mis au point une synthèse de chaînes de type oligocyclohexylidène, qui sont de bons candidats pour constituer des bras espaceurs rigides / Multi-drug resistance (MDR) is characterized by a simultaneous resistance to a wide range of structurally unrelated chemotherapeutic agents, partly caused by the efflux of active compounds out of the cell. ABC transporters (ATP-Binding Cassette) are transmembrane proteins implicated in this efflux, and thus, they contribute to the failure of some cancer treatments. Furthermore, this mechanism was evoked in some microorganism resistances to antimicrobial agents. In this study, we designed and synthesized potential inhibitors of ABC transporters, especially P-glycoprotein (Pgp) implicated in human tumors multi-drug resistance, and CpABC3, a transporter found in a human parasite, Cryptosporidium parvum. First, we synthesized three 4-alkyl-imidazo[4,5-b]pyridin-7-one derivatives, targeting ATP-binding site of ABC transporters. Their biological activities were evaluated toward a recombinant fragment of the CpABC3 transporter (H6-NBD1 fragment). One of these compounds showed a weak-binding to this fragment. Next, we prepared seventeen progesterone-adenine hybrids as potential bivalent ligands which may bind simultaneously to the ATP-binding site and the steroid-binding region. We chose to synthesize derivatives with rather short-length linkers with different conformational flexibilities. These bivalent compounds were tested on K562/R7 human leukemic cells overexpressing Pgp. One of them has showed a better activity than progesterone. Finally, we optimized the synthesis of oligocyclohexylidene chains, which are good candidates to constitute rigid linkers

Première cause de décès par cancer chez la femme, le cancer du sein développe souvent une résistance à la chimiothérapie pouvant impliquer des transporteurs ABC (ATP Binding Cassette). Ils transportent les médicaments hors de la cellule et diminuent leur efficacité thérapeutique. Nous nous sommes intéressés à la protéine ABCC11 ou MRP8 (Multidrug Resistance Protein 8), exprimée dans le sein et responsable de l’efflux de certains anticancéreux (5FdUMP et méthotrexate). Nous avons démontré que l’expression d’ABCC11 était dépendante des voies de signalisation impliquant ER (Récepteur aux œstrogènes) ou PR (Récepteurs à la Progestérone). De plus, le tamoxifène (antagoniste d’ER) et la dexaméthasone (activateur de PR), utilisés en association avec la chimiothérapie, induisent l’expression d’ABCC11 et influenceraient négativement la réponse aux traitements anticancéreux à base de substrats d’ABCC11. L’expression d’ABCC11 a été positivement corrélée à celles d’ER et PR dans des cancers du sein. En parallèle, nous avons généré 2 modèles in silico en conformation ouverte vers l’intracellulaire ou vers l’extracellulaire et identifier des acides aminés potentiellement critiques dans l’architecture de la protéine ainsi que dans la liaison avec certains substrats (5FdUMP et GMPc). Nous avons également généré les outils moléculaires permettant l’étude de l’impact de 13 SNP (Single Nucleotide Polymorphism) non synonymes d’ABCC11. En raison d’une instabilité des lignées cellulaires, l’étude n’a pu être menée à son terme. Notre travail a ainsi contribué à une meilleure caractérisation d’ABCC11 et souligne sa potentielle valeur pronostic et prédictive dans le traitement du cancer du sein. / Leading cause of woman death by cancer, breast cancer can unfortunately develops chemotherapy resistance involving ABC (ATP Binding Cassette) transporters. They transport drugs out of cells and decrease their therapeutic efficiency. We studied one ABCC sub-family member: ABCC11 or MRP8 (Multidrug Resistance Protein 8), expressed in breast and responsible for anticancer agent efflux (5FdUMP and methotrexate). We have demonstrated that ABCC11 expression was associated with ER (Estrogen Receptor) and PR (Progesterone Receptor) signaling pathways. Furthermore, tamoxifen (ER antagonist) and dexamethasone (PR activator), used in association with chemotherapy, increased ABCC11 expression and would negatively influence the response of ABCC11 substrate based anticancer treatments. Moreover, ABCC11 expression was positively correlated to ER and PR expression in breast cancer. In parallel, we have generated two in silico models obtained by homology. They represent two different spatial conformations: intracellular-facing (ready to bind substrate) or extracellular-facing (ready to release substrate). This has allowed us to identify amino acid residues potentially essential for the protein architecture and for substrate binding (5FdUMP and cGMP). In order to analyze SNP (Single Nucleotide Polymorphism) impact on ABCC11 expression and function, we generated vectors coding a wild-type or a mutated ABCC11 with 13 nonsynonymous SNPs. But, we did not succeed to create stable expressing cell lines to make a complete study of those SNPs. In conclusion, our work led to ABCC11 better characterization and underlined its putative prognostic and predictive value in breast cancer treatment.

During roughly forty years of a woman’s life-span, the fertile female human body prepares itself monthly for the possibility of pregnancy. Science has shown that the fluctuation of the sex steroids progesterone and estrogen have a crucial role in the female body's physiology, determining the menstrual cycle and its general phases. This biological dance of hormones governing the cycle influences a lot of physical, mental and cognitive aspects of life for a fertile ovulating woman. Although the question of whether these changes also affect women's cognitive performance is still unclear, some evidence has been gathered that could bring us closer to answers. Recent research findings show that this hormonal interplay might have a significant role in cognitive and psychological development - modulating brain activity, cognitive performance, higher cognition, emotional status, sensory processing, appetite and more. This thesis aims to uncover to what extent the menstrual cycle affects brain functions, neurobiology, mood, well-being and cognitive performance in menstruating cisgender women.