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Perfis endócrinos peri-ovulatórios influenciam o transporte, metabolismo e disponibilidade de aminoácidos no lúmen uterino de vacas de corte durante o diestro inicial / Pre-ovulatory endocrine profiles influence endometrial amino acids transport, metabolism and availability in the uterine lumen during early diestrus in beef cowsFrança, Moana Rodrigues 16 December 2016 (has links)
Em vacas de corte, folículos pré-ovulatórios (FPO) maiores, maiores concentrações de estradiol (E2) no proestro/estro e progesterona (P4) no diestro favorecem o crescimento do concepto e a fertilidade. Porém, os mecanismos mediados pelos esteroides femininos que influenciam a receptividade uterina ao embrião precisam ser esclarecidos. Os aminoácidos (AA) são componentes das secreções uterinas que são cruciais para a sobrevivência do embrião antes da implantação. A hipótese deste trabalho é que o tamanho do FPO e as concentrações de E2 e P4 modulam a abundância de transcritos relacionados ao transporte e metabolismo de AA no endométrio e afetam a concentração luminal de AA. Para isso, o crescimento folicular de vacas Nelore foi manipulado com o objetivo de formar dois grupos: FPO grande e CL grande (FG-CLG) e FPO pequeno e CL pequeno (FP-CLP). No Dia 4 (D4; Exp 1) e Dia 7 (D7; Exp 2) após a injeção de GnRH para indução da ovulação, foram coletados tecido endometrial e lavado uterino post-mortem. A abundância de transcritos foi avaliada por qRT-PCR e as concentrações de AA nos lavados foram quantificadas por HPLC. No Exp 1, o tamanho do FPO, concentrações plasmáticas de E2 no D-1 e de P4 no D4 foram 15,70mm±0,43 vs. 11,31mm±0,23 (p<0,01), 2,44pg/ml±0,19 vs. 0,65pg/ml (p<0,01) e 1,40ng/ml±0,23 vs. 0,80ng/ml±0,10 (p<0,01) para os grupos FG-CLG vs. FP-CLP, respectivamente. No Exp 2, o tamanho do FPO, concentrações plasmáticas de E2 no D-1 e de P4 no D7 foram 13,18mm±0,44 vs. 10,63mm±0,30 (p<0,01), 2,30pg/ml±0,57 vs. 0,50pg/ml±0,13 (p<0,01) e 3,68ng/ml±0,38 vs. 2,49ng/ml±0,43 (p=0,04) para os grupos FG-CLG vs. FP-CLP, respectivamente. No D4 a abundância de SLC1A4, SLC38A1, SLC6A6, SLC7A4 e SLCY e no D7, SLC1A4, SLC6A1, SLC6A14, SLC7A4, SLC7A8, SLC38A1, SLC38A7, SLC43A2 e DDO foi maior no endométrio dos animais do grupo FG-CLG (p<0,05). No D4, maiores concentrações de taurina, alanina e ácido α-aminobutírico foram observadas no grupo FP-CLP (p<0,05). Em contraste, menores concentrações de valina e cistationina foram encontradas nos lavados uterinos do D7 dos animais do grupo FP-CLP (p<0,05). No D4, os animais do grupo FG-CLG, associado a maior fertilidade, apresentaram menor quantidade de AA nas secreções uterinas, porém, a abundância dos transportadores de AA foi compatível com maior transporte em comparação aos animais do grupo FP-CLP. Esses resultados sugerem que antes do embrião se mover do oviduto ao útero, o transporte e metabolismo dos AA prioriza a preparação das células endometriais para receber o embrião e não o acúmulo nas secreções uterinas. Porém, no D7, quando o embrião está em contato direto com as secreções uterinas, os genes relacionados ao transporte de AA no endométrio e a concentração de AA no histotrofo são estimulados nas vacas do grupo FG-CLG. Portanto o metabolismo e transporte de AA no sentido das células endometriais ou das secreções uterinas pode ser um mecanismo importante para a receptividade materna. / In beef cattle, a large size of the pre-ovulatory follicle (POF) and resulting elevated proestrus/estrus estradiol (E2) and diestrus progesterone (P4) concentrations positively affect conceptus growth and fertility. However, sex-steroid-mediated mechanisms that influence uterine receptivity to the embryo need to be elucidated. Amino acids are important components of maternally-derived secretions that are crucial for embryo survival before implantation. The hypothesis is that the size of the POF, E2 and P4 concentrations modulate endometrial abundance of solute carrier proteins (SLC) transcripts related to AA transport and metabolism and subsequently affect lumenal amino acids concentrations. Therefore, follicle growth of Nelore cows was manipulated to produce two experimental groups: large POF and CL (LF-LCL group) and small POF and CL (SF-SCL group). On Day 4 (D4; Experiment 1) and Day 7 (D7; Experiment 2) post GnRH injection to induce ovulation, endometrial tissue and uterine washings were collected post-mortem. Transcript abundance was evaluated by qRT-PCR and amino acid concentrations were quantified in washings by HPLC. On Experiment 1, POF size, plasma E2 concentration on D-1, and plasma concentration of P4 on D4 were 15.70mm±0.43 vs. 11.31mm±0.23 (p<0.01), 2.44pg/ml±0.19 vs. 0.65pg/ml (p<0.01) and 1.40ng/ml±0.23 vs. 0.80ng/ml±0.10 (p<0.01) for the LF-LCL vs. SF-SCL groups, respectively. For Experiment 2, POF size, plasma E2 concentration on D-1 and plasma P4 concentration on D7 were 13.18mm±0.44 vs. 10.63mm±0.30 (p<0.01), 2.30pg/ml±0.57 vs. 0.50pg/ml±0.13 (p<0.01) and 3.68ng/ml±0.38 vs. 2.49ng/ml±0.43 (p=0.04) for the LF-LCL vs. SF-SCL groups, respectively. On D4, abundance of SLC6A6, SLC7A4, SLC17A5, SLC38A1, SLC38A7 and SLCY and on D7, SLC1A4, SLC6A1, SLC6A14, SLC7A4, SLC7A7, SLC7A8, SLC17A5, SLC38A1, SLC38A7, SLC43A2 and DDO was greater in the endometrium of cows from the LF-LCL group (p<0.05). On D4, higher concentrations of taurine, alanine and α-aminobutiric acid were observed in SF-SCL (p<0.05). In contrast, lower concentrations of valine and cystathionine were quantified in D7 uterine washings from SF-SCL cows (p<0.05). On D4, animals from LF-LCL group, associated with greater fertility, presented less amino acid content in uterine secretion but abundance of transporters was compatible to greater transport in comparison to animals from SF-SCL group. This suggests that before embryo moves from oviduct to uterus, amino acids transport and metabolism pathways prioritizes endometrium cells preparation for receiving the embryo but not accumulation in uterine secretions. However, on D7, when the embryo is in direct contact with uterine secretions, genes related to amino acids transport in endometrium and amino acids concentration in histotroph are up-regulated in LF-LCL cows. The latter insights indicate that amino acids metabolism and transport, towards endometrial cells or uterine secretions, might be mechanisms contributing to maternal receptivity.
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Esteroidogênese testicular durante o desenvolvimento sexual pós-natal em Galea spixii (Wagler, 1831) / Testicular steroidogenesis during post-natal sexual development in Galea spixii (Wagler, 1831)Santos, Paulo Ramos da Silva 04 November 2016 (has links)
O desenvolvimento testicular e a manutenção da espermatogênese são controlados por gonadotrofinas e testosterona, cujos efeitos são modulados por uma rede complexa de fatores produzidos localmente e, entre eles, os estrógenos estão em causa. Uma compreensão da dinâmica dos hormônios esteroides sexuais mostra-se importante para revelar as funções durante o desenvolvimento testicular. Sendo assim, este trabalho teve como objetivo aprofundar os conhecimentos sobre a espermatogênese do Galea spixii, associando a atuação das enzimas do complexo citocromo P450: P450 aromatase e P450c17 (17-α-hidroxilase/17,20-liase) importantes para a biossíntese de hormônios ligados à reprodução durante o desenvolvimento sexual pós-natal. Fragmentos de testículos de preás machos nas fases impúbere, pré-púbere, púbere e pós-púbere foram coletados no Centro de Multiplicação da Universidade Federal Rural do Semiárido, Mossoró, RN, fixados em Paraformoaldeido 4% e RNAlater, e processados para Imunohistoquímica e PCR em tempo real. A expressão gênica das enzimas esteroidogênicas foram cruciais da prépuberdade para a puberdade. Durante as fases do desenvolvimento sexual a enzima P450c17 apresentou imunomarcação positiva apenas nas células de Leydig. A imunomarcação da enzima P450 aromatase foi positiva em diferentes tipos celulares ao longo do desenvolvimento sexual. A síntese de estrógenos no parênquima testicular não ficou restrita às células somáticas, as células germinativas também mostraram capacidade de converter andrógenos em estrógenos / The testis development and maintenance of spermatogenesis are controlled by gonadotropins and testosterone, whose effects are modulated by a complex factor locally produced, and the estrogens are involved. An understanding of the dynamics of sex steroid hormones shown to be important to reveal the functions during testicular development. Thus, the aimed was study the spermatogenesis of Galea spixii, associating the performance of cytochrome P450 complex: P450 aromatase and P450c17 (17-α-hydroxylase / 17,20-lyase) important for the biosynthesis of hormones related to reproduction during postnatal sexual development. Fragments of testes of immature, prepubertal, pubertal and post-pubertal were collected at Centro de Multiplicação da Universidade Federal Rural do Semiárido, Mossoró, RN, fixed in Paraformaldehyde 4% and RNAlater, processed for immunohistochemistry and real time PCR. The steroidogenic enzymes gene expression were significant from prepubertal to pubertal stage. Cytochrome P450c17 expression in testicular parenchyma showed a positive reaction only in Leydig cell clusters. The expression of cytochrome P450 aromatase in testicular parenchyma were different during the sexual development of Galea spixii. During sexual development was observed that estrogen synthesis was not restricted to somatic cells (Leydig cells / Sertoli cells), the germ cells have also shown to be capable to convert androgens into estrogens via aromatase
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Perfis endócrinos peri-ovulatórios influenciam o transporte, metabolismo e disponibilidade de aminoácidos no lúmen uterino de vacas de corte durante o diestro inicial / Pre-ovulatory endocrine profiles influence endometrial amino acids transport, metabolism and availability in the uterine lumen during early diestrus in beef cowsMoana Rodrigues França 16 December 2016 (has links)
Em vacas de corte, folículos pré-ovulatórios (FPO) maiores, maiores concentrações de estradiol (E2) no proestro/estro e progesterona (P4) no diestro favorecem o crescimento do concepto e a fertilidade. Porém, os mecanismos mediados pelos esteroides femininos que influenciam a receptividade uterina ao embrião precisam ser esclarecidos. Os aminoácidos (AA) são componentes das secreções uterinas que são cruciais para a sobrevivência do embrião antes da implantação. A hipótese deste trabalho é que o tamanho do FPO e as concentrações de E2 e P4 modulam a abundância de transcritos relacionados ao transporte e metabolismo de AA no endométrio e afetam a concentração luminal de AA. Para isso, o crescimento folicular de vacas Nelore foi manipulado com o objetivo de formar dois grupos: FPO grande e CL grande (FG-CLG) e FPO pequeno e CL pequeno (FP-CLP). No Dia 4 (D4; Exp 1) e Dia 7 (D7; Exp 2) após a injeção de GnRH para indução da ovulação, foram coletados tecido endometrial e lavado uterino post-mortem. A abundância de transcritos foi avaliada por qRT-PCR e as concentrações de AA nos lavados foram quantificadas por HPLC. No Exp 1, o tamanho do FPO, concentrações plasmáticas de E2 no D-1 e de P4 no D4 foram 15,70mm±0,43 vs. 11,31mm±0,23 (p<0,01), 2,44pg/ml±0,19 vs. 0,65pg/ml (p<0,01) e 1,40ng/ml±0,23 vs. 0,80ng/ml±0,10 (p<0,01) para os grupos FG-CLG vs. FP-CLP, respectivamente. No Exp 2, o tamanho do FPO, concentrações plasmáticas de E2 no D-1 e de P4 no D7 foram 13,18mm±0,44 vs. 10,63mm±0,30 (p<0,01), 2,30pg/ml±0,57 vs. 0,50pg/ml±0,13 (p<0,01) e 3,68ng/ml±0,38 vs. 2,49ng/ml±0,43 (p=0,04) para os grupos FG-CLG vs. FP-CLP, respectivamente. No D4 a abundância de SLC1A4, SLC38A1, SLC6A6, SLC7A4 e SLCY e no D7, SLC1A4, SLC6A1, SLC6A14, SLC7A4, SLC7A8, SLC38A1, SLC38A7, SLC43A2 e DDO foi maior no endométrio dos animais do grupo FG-CLG (p<0,05). No D4, maiores concentrações de taurina, alanina e ácido α-aminobutírico foram observadas no grupo FP-CLP (p<0,05). Em contraste, menores concentrações de valina e cistationina foram encontradas nos lavados uterinos do D7 dos animais do grupo FP-CLP (p<0,05). No D4, os animais do grupo FG-CLG, associado a maior fertilidade, apresentaram menor quantidade de AA nas secreções uterinas, porém, a abundância dos transportadores de AA foi compatível com maior transporte em comparação aos animais do grupo FP-CLP. Esses resultados sugerem que antes do embrião se mover do oviduto ao útero, o transporte e metabolismo dos AA prioriza a preparação das células endometriais para receber o embrião e não o acúmulo nas secreções uterinas. Porém, no D7, quando o embrião está em contato direto com as secreções uterinas, os genes relacionados ao transporte de AA no endométrio e a concentração de AA no histotrofo são estimulados nas vacas do grupo FG-CLG. Portanto o metabolismo e transporte de AA no sentido das células endometriais ou das secreções uterinas pode ser um mecanismo importante para a receptividade materna. / In beef cattle, a large size of the pre-ovulatory follicle (POF) and resulting elevated proestrus/estrus estradiol (E2) and diestrus progesterone (P4) concentrations positively affect conceptus growth and fertility. However, sex-steroid-mediated mechanisms that influence uterine receptivity to the embryo need to be elucidated. Amino acids are important components of maternally-derived secretions that are crucial for embryo survival before implantation. The hypothesis is that the size of the POF, E2 and P4 concentrations modulate endometrial abundance of solute carrier proteins (SLC) transcripts related to AA transport and metabolism and subsequently affect lumenal amino acids concentrations. Therefore, follicle growth of Nelore cows was manipulated to produce two experimental groups: large POF and CL (LF-LCL group) and small POF and CL (SF-SCL group). On Day 4 (D4; Experiment 1) and Day 7 (D7; Experiment 2) post GnRH injection to induce ovulation, endometrial tissue and uterine washings were collected post-mortem. Transcript abundance was evaluated by qRT-PCR and amino acid concentrations were quantified in washings by HPLC. On Experiment 1, POF size, plasma E2 concentration on D-1, and plasma concentration of P4 on D4 were 15.70mm±0.43 vs. 11.31mm±0.23 (p<0.01), 2.44pg/ml±0.19 vs. 0.65pg/ml (p<0.01) and 1.40ng/ml±0.23 vs. 0.80ng/ml±0.10 (p<0.01) for the LF-LCL vs. SF-SCL groups, respectively. For Experiment 2, POF size, plasma E2 concentration on D-1 and plasma P4 concentration on D7 were 13.18mm±0.44 vs. 10.63mm±0.30 (p<0.01), 2.30pg/ml±0.57 vs. 0.50pg/ml±0.13 (p<0.01) and 3.68ng/ml±0.38 vs. 2.49ng/ml±0.43 (p=0.04) for the LF-LCL vs. SF-SCL groups, respectively. On D4, abundance of SLC6A6, SLC7A4, SLC17A5, SLC38A1, SLC38A7 and SLCY and on D7, SLC1A4, SLC6A1, SLC6A14, SLC7A4, SLC7A7, SLC7A8, SLC17A5, SLC38A1, SLC38A7, SLC43A2 and DDO was greater in the endometrium of cows from the LF-LCL group (p<0.05). On D4, higher concentrations of taurine, alanine and α-aminobutiric acid were observed in SF-SCL (p<0.05). In contrast, lower concentrations of valine and cystathionine were quantified in D7 uterine washings from SF-SCL cows (p<0.05). On D4, animals from LF-LCL group, associated with greater fertility, presented less amino acid content in uterine secretion but abundance of transporters was compatible to greater transport in comparison to animals from SF-SCL group. This suggests that before embryo moves from oviduct to uterus, amino acids transport and metabolism pathways prioritizes endometrium cells preparation for receiving the embryo but not accumulation in uterine secretions. However, on D7, when the embryo is in direct contact with uterine secretions, genes related to amino acids transport in endometrium and amino acids concentration in histotroph are up-regulated in LF-LCL cows. The latter insights indicate that amino acids metabolism and transport, towards endometrial cells or uterine secretions, might be mechanisms contributing to maternal receptivity.
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Cross-Talk Between Estrogen and Thyroid Hormones During Amphibian DevelopmentDuarte Guterman, Paula 09 May 2011 (has links)
It is generally thought that in amphibians, thyroid hormones (THs) regulate metamorphosis, while sex steroids (estrogens and androgens) regulate gonadal differentiation. However, inhibition of TH synthesis in frogs alters gonadal differentiation, suggesting instead that these two endocrine axes interact during development. Specifically, THs may be involved in male development, while estrogens may inhibit tadpole metamorphosis. However, we do not currently know the mechanisms that account for these interactions, let alone how such mechanisms may differ between species. To develop and test new hypotheses on the roles of sex steroids and THs, I first examined transcriptional profiles (mRNA) of enzymes and receptors related to sex steroids and THs during embryogenesis and metamorphosis in Silurana tropicalis. Tadpoles were exposed to either an estrogen synthesis inhibitor (fadrozole) or TH (triiodothyronine, T3) during early larval or tadpole development. Acute exposures of S. tropicalis to fadrozole or T3 during early development resulted in increased expression of androgen- and TH-related genes in whole body larvae, while chronic exposure to fadrozole during metamorphosis affected gonadal differentiation but did not affect tadpole development. On the other hand, acute exposure to T3 during metamorphosis increased the expression of androgen-related transcripts both in the brain and gonad. In S. tropicalis, the results suggested that cross-talk is primarily in one direction (i.e., effect of THs on the reproductive axis) with a strong relationship between TH and androgen status. Lastly, I established developmental transcript profiles and investigated T3 regulation of brain and gonad transcripts in Engystomops pustulosus. I then compared these results with S. tropicalis and an earlier study in Lithobates pipiens. While each species developed with similar profiles, they differed in their response to T3. Exposure to T3 resulted in either an increase in androgen-related genes (S. tropicalis) or a decrease in estrogen-related genes (E. pustulosus and L. pipiens). In conclusion, these data demonstrated that cross-talk mechanisms differ among these three evolutionary separate species, but in all cases, T3 appears to affect the balance of sex steroids, stimulating the androgen system and providing potential mechanisms of the masculinising effects of THs. These results will contribute to understanding the mechanisms of hormone interactions and their evolutionary basis in frogs.
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Cross-Talk Between Estrogen and Thyroid Hormones During Amphibian DevelopmentDuarte Guterman, Paula 09 May 2011 (has links)
It is generally thought that in amphibians, thyroid hormones (THs) regulate metamorphosis, while sex steroids (estrogens and androgens) regulate gonadal differentiation. However, inhibition of TH synthesis in frogs alters gonadal differentiation, suggesting instead that these two endocrine axes interact during development. Specifically, THs may be involved in male development, while estrogens may inhibit tadpole metamorphosis. However, we do not currently know the mechanisms that account for these interactions, let alone how such mechanisms may differ between species. To develop and test new hypotheses on the roles of sex steroids and THs, I first examined transcriptional profiles (mRNA) of enzymes and receptors related to sex steroids and THs during embryogenesis and metamorphosis in Silurana tropicalis. Tadpoles were exposed to either an estrogen synthesis inhibitor (fadrozole) or TH (triiodothyronine, T3) during early larval or tadpole development. Acute exposures of S. tropicalis to fadrozole or T3 during early development resulted in increased expression of androgen- and TH-related genes in whole body larvae, while chronic exposure to fadrozole during metamorphosis affected gonadal differentiation but did not affect tadpole development. On the other hand, acute exposure to T3 during metamorphosis increased the expression of androgen-related transcripts both in the brain and gonad. In S. tropicalis, the results suggested that cross-talk is primarily in one direction (i.e., effect of THs on the reproductive axis) with a strong relationship between TH and androgen status. Lastly, I established developmental transcript profiles and investigated T3 regulation of brain and gonad transcripts in Engystomops pustulosus. I then compared these results with S. tropicalis and an earlier study in Lithobates pipiens. While each species developed with similar profiles, they differed in their response to T3. Exposure to T3 resulted in either an increase in androgen-related genes (S. tropicalis) or a decrease in estrogen-related genes (E. pustulosus and L. pipiens). In conclusion, these data demonstrated that cross-talk mechanisms differ among these three evolutionary separate species, but in all cases, T3 appears to affect the balance of sex steroids, stimulating the androgen system and providing potential mechanisms of the masculinising effects of THs. These results will contribute to understanding the mechanisms of hormone interactions and their evolutionary basis in frogs.
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Malignant glioma : experimental studies with an estrogen-linked cytostaticSchoultz, Eva von January 1990 (has links)
Malignant gliomas are the most common primary brain tumors in adults. Patients with these highly malignant tumors have an extremely poor prognosis. The situation with a highly proliferative tumor in a non-proliferating tissue should favor cytostatic treatment but so far the role of conventional chemotherapy has been adjunctive. The concentrations of three sex steroids, estradiol, progesterone and testosterone, were analyzed by radioimmunoassay after celite chromatography in brain tumor samples. Some malignant gliomas had high tissue concentrations of estradiol. Low progesterone levels may suggest steroid consumption. Estramustine (EM), a conjugate of estradiol-17ß and nornitrogen mustard had a dose-dependent antiproliferative effect on several human malignant glioma cell lines. At equimolar concentrations the inhibitory effects of the EM complex were clearly more pronounced than those of estradiol and nornitrogen mustard given alone or in combination. A specific binding protein (EMBP) is important for the cytotoxic action of EM. Using a mouse monoclonal antibody and an indirect antibodyperoxidase technique, EMBP was demonstrated in human glioma cells. Significant amounts of EMBP were also detected in human brain tumor tissue by radioimmunoassay. The mean concentrations (ng/mg protein) in 16 astrocytomas (2.6) and 7 meningiomas (5.1) were higher (p<0.001) than in 18 samples of normal brain (0.5). The presence of the specific binding protein may suggest a selective binding and effect of EM in human brain tumor tissue. Human glioma cells displayed significant uptake, retention and metabolism of estramustine phosphate (EMP). After incubation with ^H-EMP a progressive uptake of radioactivity was recorded during 24 hours. Metabolism of parent EMP into estramustine and estromustine, which is a well known part of the metabolic pathway in man, was also demonstrated. A dose- dependent increase in DNA strand breaks was recorded at EMP- concentrations ranging 10-40 yg/ml. The uptake of ®^Rb, used as a tracer for potassium to study ion transport and membrane permeability, was reduced after incubation with EMP. Scanning electron microscopy gave further evidence for membrane damage. According to flow cytometric analyses exponentially growing glioma cells were accumulated in the G2/M stage and the fraction of Gi/Gq was reduced. EM seems to attack malignant cells in a multifocal fashion on several vital functions including the microtubule, the nucleus, and the cell membrane. The intact EM complex may be important for effects related to microtubule function which add to the cytotoxic potential of its constituents. These experimental findings justify further investigations on the role of sex hormones in brain tumor growth and development and of hormone-linked cytostatics in clinical treatment. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1990, härtill 6 uppsatser.</p> / digitalisering@umu
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Cross-Talk Between Estrogen and Thyroid Hormones During Amphibian DevelopmentDuarte Guterman, Paula 09 May 2011 (has links)
It is generally thought that in amphibians, thyroid hormones (THs) regulate metamorphosis, while sex steroids (estrogens and androgens) regulate gonadal differentiation. However, inhibition of TH synthesis in frogs alters gonadal differentiation, suggesting instead that these two endocrine axes interact during development. Specifically, THs may be involved in male development, while estrogens may inhibit tadpole metamorphosis. However, we do not currently know the mechanisms that account for these interactions, let alone how such mechanisms may differ between species. To develop and test new hypotheses on the roles of sex steroids and THs, I first examined transcriptional profiles (mRNA) of enzymes and receptors related to sex steroids and THs during embryogenesis and metamorphosis in Silurana tropicalis. Tadpoles were exposed to either an estrogen synthesis inhibitor (fadrozole) or TH (triiodothyronine, T3) during early larval or tadpole development. Acute exposures of S. tropicalis to fadrozole or T3 during early development resulted in increased expression of androgen- and TH-related genes in whole body larvae, while chronic exposure to fadrozole during metamorphosis affected gonadal differentiation but did not affect tadpole development. On the other hand, acute exposure to T3 during metamorphosis increased the expression of androgen-related transcripts both in the brain and gonad. In S. tropicalis, the results suggested that cross-talk is primarily in one direction (i.e., effect of THs on the reproductive axis) with a strong relationship between TH and androgen status. Lastly, I established developmental transcript profiles and investigated T3 regulation of brain and gonad transcripts in Engystomops pustulosus. I then compared these results with S. tropicalis and an earlier study in Lithobates pipiens. While each species developed with similar profiles, they differed in their response to T3. Exposure to T3 resulted in either an increase in androgen-related genes (S. tropicalis) or a decrease in estrogen-related genes (E. pustulosus and L. pipiens). In conclusion, these data demonstrated that cross-talk mechanisms differ among these three evolutionary separate species, but in all cases, T3 appears to affect the balance of sex steroids, stimulating the androgen system and providing potential mechanisms of the masculinising effects of THs. These results will contribute to understanding the mechanisms of hormone interactions and their evolutionary basis in frogs.
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Parâmetros mecânicos, físicos e químicos na avaliação de mandíbulas de ratos deficientes em esteróides sexuais / Mechanical, physical and chemical parameters in mandible evaluation of sex steroid deficiency ratsLuciana Armada Dias 19 February 2009 (has links)
O aumento da expectativa de vida vem elevando a ocorrência das alterações degenerativas comuns à terceira idade, como a osteoporose. Essa doença sistêmica também freqüente no hipogonadismo, afeta o metabolismo ósseo comprometendo
inclusive a mandíbula. O objetivo deste estudo foi avaliar de que forma a deficiência de esteróides sexuais, induzida por orquiectomia ou ovariectomia, influencia o processo de remodelação óssea da mandíbula de ratos por períodos experimentais crônicos. Ratos Wistar, com 3 meses, foram divididos em três grupos experimentais: controles (C), castrados (ORQ; OVX) e castrados com tratamento hormonal (ORQ + PT - propionato de testosterona, 0,4 mg/100g PC/dia; OVX + BE - benzoato de estradiol, 0,7 g/100g PC/dia). As fêmeas foram previamente avaliadas por citologia vaginal e somente as que apresentaram o ciclo estral regular foram utilizadas. A massa corporal foi verificada semanalmente e ao final dos períodos experimentais (90, 120 e 150 dias) os animais foram sacrificados. O sangue foi coletado e o soro
armazenado para posterior análise. As mandíbulas, fêmures e colunas foram excisados, medidos e preparados para análises da densidade mineral óssea e das propriedades físicas e biomecânicas. Observamos que com a castração, machos
apresentaram baixo ganho de massa corporal (90d: 12%, 120d: 24% e 150d: 13% a menos que C, p< 0,05), ao contrário das fêmeas (90d: 38% e 120d: 41% a mais que
C, p< 0,05). As medidas de todos os ossos foram menores tanto em machos como em fêmeas (♂ - 90d: vértebra 11.8%, fêmur 4.4%, côndilo MD 9.4%, côndilo VL 16.6%; 120d: vértebra 13.6%, fêmur 4%, côndilo mandibular MD 9%, côndilo
mandibular VL 22.2%; 150d: vértebra 16.8%, fêmur 6% , côndilo mandibular MD 21.6%, côndilo mandibular VL 29.1% e ♀ - 90d: vértebra 7.7%, fêmur 5.6%, côndilo mandibular MD 29.1 %, côndilo mandibular VL 11.8%; 120d: vértebra 15.9 %, fêmur 6.1%, côndilo mandibular MD 33.6%, côndilo mandibular VL 14.8%; 150d: vértebra 21.6%, fêmur 5.42%, côndilo mandibular MD 29.1%, côndilo mandibular VL 15.1% a menos que C, p< 0,05), em todos os períodos experimentais. Em ambos os sexos as concentrações séricas de esteróides sexuais, fósforo e fosfatase alcalina foram menores em relação ao grupo controle, p<0,05 (Testosterona - 90d: 87%,120d: 87.5%,150d: 90.4%; Estradiol - 90d: 85.8%, 120d: 80.8%, 150d: 71.5%; Fósforo - ORQ - 120d: 7.5%, 150d: 9.2% e OVX 90d: 17.2%, 120d: 16%, 150d: 24%;
Fosfatase alcalina - ORQ - 90d: 7%, 120d: 6.8%, 150d: 9.5% e OVX 90d: 21.2%, 120d: 26.1%, 150d: 43.3%). As concentrações séricas de cálcio não diferiram significativamente entre machos, mas foram menores em fêmeas castradas (90d: 13.1%, 120d: 11.7%, 150d: 26.2%, p< 0,05). As análises da densidade mineral óssea (DMO) e das propriedades biomecânicas de vértebras e fêmures
apresentaram diminuição mais precoce em fêmeas do que em machos (♀ - vértebras a partir de 90d e fêmures a partir de 120d; ♂ - vértebras a partir de 120d e fêmures a partir de 150, p< 0,05). No entanto, as mandíbulas apenas foram afetadas nos machos aos 150 dias. As propriedades físicas não apresentaram alterações significativas. Concluímos que a perda da função gonadal provoca redução de massa óssea, preferencialmente do osso trabecular, atingindo fêmeas mais
precocemente do que machos e acentuando-se com o avançar da idade. O osso mandibular é acometido em períodos crônicos principalmente se estiver associada a um comprometimento da atividade mastigatória. Os efeitos ósseos decorrentes do hipogonadismo foram minimizados pelo tratamento com benzoato de estradiol ou propionato de testosterona, em fêmeas e machos, respectivamente. / The increase in the life expectancy has been raising the occurrence of common degenerative alterations in aging population, as osteoporosis. This systemic disease is also frequent in hypogonadism and affects the bone metabolism, included mandibular bone. The aim of this study was to evaluate how sex steroid deficiency, induced by orchiectomy (ORX) or ovariectomy (OVX), influences on mandible bone
remodeling of rats, in groups of chronic experimental periods. Wistar rats, 3 mouths, had been divided in three groups: controls (C), castrated (ORX; OVX) and castrated with hormonal treatment (ORX+TP testosterone propionate, 0,4 mg/100g BW/day; OVX+EB - estradiol benzoate, 0.7 g/100g BW/day). Females were previously evaluated by vaginal cytology and only rats with regular estrous cycle were used. The corporal mass was weekly verified and after experimental periods (90, 120 and 150 days), the animals were sacrificed. The blood was collected and serum stored for posterior analysis. Mandibles, femurs and columns were excised, measured and prepared to analyses of bone mineral density and physical and biomechanical properties. After castration, males presented low gain in body mass (90d: 12%, 120d:
24% and 150d: 13% lower than C, p< 0,05), in contrast of females (90d: 38% and 120d: 41% upper than C, p< 0,05). The measures of all bones were lower in males and in females (♂ - 90d: vertebrae 11.8%, femur 4.4%, mandibular condyle MD 9.4%, mandibular condyle VL 16.6%; 120d: vertebrae 13.6%, femur 4%, mandibular condyle MD 9%, mandibular condyle VL 22.2%; 150d: vertebrae 16.8%, femur 6% ,
mandibular condyle MD 21.6%, mandibular condyle VL 29.1% and ♀ - 90d: vertebrae 7.7%, femur 5.6%, mandibular condyle MD 29.1 %, mandibular condyle VL 11.8%; 120d: vertebrae 15.9 %, femur 6.1%, mandibular condyle MD 33.6%,
mandibular condyle VL 14.8% and 150d: vertebrae 21.6%, femur 5.42%, mandibular condyle MD 29.1%, mandibular condyle VL 15.1% lower than C, p< 0,05), in all experimental periods. Males and females presented serum concentration of sex steroid hormones, phosphate and alkaline phosphatase lower than control group, p< 0,05 (Testosterone - 90d: 87%,120d: 87.5%,150d: 90.4%; Estradiol - 90d: 85.8%, 120d: 80.8%, 150d: 71.5%; Phosphate - ORX - 120d: 7.5%, 150d: 9.2% and OVX 90d: 17.2%, 120d: 16%, 150d: 24%; Alkaline phosphatase - ORX - 90d: 7%, 120d: 6.8%, 150d: 9.5% and OVX 90d: 21.2%, 120d: 26.1%, 150d: 43.3%). No significant differences were found in the males calcium concentration, but it was lower in castrated females (90d: 13.1%, 120d: 11.7%, 150d: 26.2%, p< 0,05).The bone mineral density and biomechanical properties of vertebrae and femur were reduced earlier in females than in males (♀ - vertebrae from 90d and femur from 120d; ♂ - vertebrae from 120d and femur from 150d, p< 0,05). However, mandibles were
affected only in 150d males. There werent significant alterations on the physical properties. In conclusion, gonadal function loss caused low bone mass, preferentially in trabecular bone, affected females earliest than males and its decreases more with aging. Mandibular bone is affected in chronic periods principally when associated with masticatory activities alterations. Bones alterations resulted from Hypogonadism were minimized, by estradiol benzoate or testosterone propionate treatment, in female and male, respectively.
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Parâmetros mecânicos, físicos e químicos na avaliação de mandíbulas de ratos deficientes em esteróides sexuais / Mechanical, physical and chemical parameters in mandible evaluation of sex steroid deficiency ratsLuciana Armada Dias 19 February 2009 (has links)
O aumento da expectativa de vida vem elevando a ocorrência das alterações degenerativas comuns à terceira idade, como a osteoporose. Essa doença sistêmica também freqüente no hipogonadismo, afeta o metabolismo ósseo comprometendo
inclusive a mandíbula. O objetivo deste estudo foi avaliar de que forma a deficiência de esteróides sexuais, induzida por orquiectomia ou ovariectomia, influencia o processo de remodelação óssea da mandíbula de ratos por períodos experimentais crônicos. Ratos Wistar, com 3 meses, foram divididos em três grupos experimentais: controles (C), castrados (ORQ; OVX) e castrados com tratamento hormonal (ORQ + PT - propionato de testosterona, 0,4 mg/100g PC/dia; OVX + BE - benzoato de estradiol, 0,7 g/100g PC/dia). As fêmeas foram previamente avaliadas por citologia vaginal e somente as que apresentaram o ciclo estral regular foram utilizadas. A massa corporal foi verificada semanalmente e ao final dos períodos experimentais (90, 120 e 150 dias) os animais foram sacrificados. O sangue foi coletado e o soro
armazenado para posterior análise. As mandíbulas, fêmures e colunas foram excisados, medidos e preparados para análises da densidade mineral óssea e das propriedades físicas e biomecânicas. Observamos que com a castração, machos
apresentaram baixo ganho de massa corporal (90d: 12%, 120d: 24% e 150d: 13% a menos que C, p< 0,05), ao contrário das fêmeas (90d: 38% e 120d: 41% a mais que
C, p< 0,05). As medidas de todos os ossos foram menores tanto em machos como em fêmeas (♂ - 90d: vértebra 11.8%, fêmur 4.4%, côndilo MD 9.4%, côndilo VL 16.6%; 120d: vértebra 13.6%, fêmur 4%, côndilo mandibular MD 9%, côndilo
mandibular VL 22.2%; 150d: vértebra 16.8%, fêmur 6% , côndilo mandibular MD 21.6%, côndilo mandibular VL 29.1% e ♀ - 90d: vértebra 7.7%, fêmur 5.6%, côndilo mandibular MD 29.1 %, côndilo mandibular VL 11.8%; 120d: vértebra 15.9 %, fêmur 6.1%, côndilo mandibular MD 33.6%, côndilo mandibular VL 14.8%; 150d: vértebra 21.6%, fêmur 5.42%, côndilo mandibular MD 29.1%, côndilo mandibular VL 15.1% a menos que C, p< 0,05), em todos os períodos experimentais. Em ambos os sexos as concentrações séricas de esteróides sexuais, fósforo e fosfatase alcalina foram menores em relação ao grupo controle, p<0,05 (Testosterona - 90d: 87%,120d: 87.5%,150d: 90.4%; Estradiol - 90d: 85.8%, 120d: 80.8%, 150d: 71.5%; Fósforo - ORQ - 120d: 7.5%, 150d: 9.2% e OVX 90d: 17.2%, 120d: 16%, 150d: 24%;
Fosfatase alcalina - ORQ - 90d: 7%, 120d: 6.8%, 150d: 9.5% e OVX 90d: 21.2%, 120d: 26.1%, 150d: 43.3%). As concentrações séricas de cálcio não diferiram significativamente entre machos, mas foram menores em fêmeas castradas (90d: 13.1%, 120d: 11.7%, 150d: 26.2%, p< 0,05). As análises da densidade mineral óssea (DMO) e das propriedades biomecânicas de vértebras e fêmures
apresentaram diminuição mais precoce em fêmeas do que em machos (♀ - vértebras a partir de 90d e fêmures a partir de 120d; ♂ - vértebras a partir de 120d e fêmures a partir de 150, p< 0,05). No entanto, as mandíbulas apenas foram afetadas nos machos aos 150 dias. As propriedades físicas não apresentaram alterações significativas. Concluímos que a perda da função gonadal provoca redução de massa óssea, preferencialmente do osso trabecular, atingindo fêmeas mais
precocemente do que machos e acentuando-se com o avançar da idade. O osso mandibular é acometido em períodos crônicos principalmente se estiver associada a um comprometimento da atividade mastigatória. Os efeitos ósseos decorrentes do hipogonadismo foram minimizados pelo tratamento com benzoato de estradiol ou propionato de testosterona, em fêmeas e machos, respectivamente. / The increase in the life expectancy has been raising the occurrence of common degenerative alterations in aging population, as osteoporosis. This systemic disease is also frequent in hypogonadism and affects the bone metabolism, included mandibular bone. The aim of this study was to evaluate how sex steroid deficiency, induced by orchiectomy (ORX) or ovariectomy (OVX), influences on mandible bone
remodeling of rats, in groups of chronic experimental periods. Wistar rats, 3 mouths, had been divided in three groups: controls (C), castrated (ORX; OVX) and castrated with hormonal treatment (ORX+TP testosterone propionate, 0,4 mg/100g BW/day; OVX+EB - estradiol benzoate, 0.7 g/100g BW/day). Females were previously evaluated by vaginal cytology and only rats with regular estrous cycle were used. The corporal mass was weekly verified and after experimental periods (90, 120 and 150 days), the animals were sacrificed. The blood was collected and serum stored for posterior analysis. Mandibles, femurs and columns were excised, measured and prepared to analyses of bone mineral density and physical and biomechanical properties. After castration, males presented low gain in body mass (90d: 12%, 120d:
24% and 150d: 13% lower than C, p< 0,05), in contrast of females (90d: 38% and 120d: 41% upper than C, p< 0,05). The measures of all bones were lower in males and in females (♂ - 90d: vertebrae 11.8%, femur 4.4%, mandibular condyle MD 9.4%, mandibular condyle VL 16.6%; 120d: vertebrae 13.6%, femur 4%, mandibular condyle MD 9%, mandibular condyle VL 22.2%; 150d: vertebrae 16.8%, femur 6% ,
mandibular condyle MD 21.6%, mandibular condyle VL 29.1% and ♀ - 90d: vertebrae 7.7%, femur 5.6%, mandibular condyle MD 29.1 %, mandibular condyle VL 11.8%; 120d: vertebrae 15.9 %, femur 6.1%, mandibular condyle MD 33.6%,
mandibular condyle VL 14.8% and 150d: vertebrae 21.6%, femur 5.42%, mandibular condyle MD 29.1%, mandibular condyle VL 15.1% lower than C, p< 0,05), in all experimental periods. Males and females presented serum concentration of sex steroid hormones, phosphate and alkaline phosphatase lower than control group, p< 0,05 (Testosterone - 90d: 87%,120d: 87.5%,150d: 90.4%; Estradiol - 90d: 85.8%, 120d: 80.8%, 150d: 71.5%; Phosphate - ORX - 120d: 7.5%, 150d: 9.2% and OVX 90d: 17.2%, 120d: 16%, 150d: 24%; Alkaline phosphatase - ORX - 90d: 7%, 120d: 6.8%, 150d: 9.5% and OVX 90d: 21.2%, 120d: 26.1%, 150d: 43.3%). No significant differences were found in the males calcium concentration, but it was lower in castrated females (90d: 13.1%, 120d: 11.7%, 150d: 26.2%, p< 0,05).The bone mineral density and biomechanical properties of vertebrae and femur were reduced earlier in females than in males (♀ - vertebrae from 90d and femur from 120d; ♂ - vertebrae from 120d and femur from 150d, p< 0,05). However, mandibles were
affected only in 150d males. There werent significant alterations on the physical properties. In conclusion, gonadal function loss caused low bone mass, preferentially in trabecular bone, affected females earliest than males and its decreases more with aging. Mandibular bone is affected in chronic periods principally when associated with masticatory activities alterations. Bones alterations resulted from Hypogonadism were minimized, by estradiol benzoate or testosterone propionate treatment, in female and male, respectively.
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Prolactinemia em indivíduos com deficiência congênita e isolada do hormônio de crescimento / Prolactinemia in deficiecy and congenital isolated growth hormoneMenezes, Menilson 05 April 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Growth hormone (GH) and prolactin share similarities in structure and function. We have previously shown that women with congenital isolated GH deficiency (IGHD) caused by a homozygous mutation in the GHRH receptor gene (GHRHR) (MUT/MUT) have a short reproductive life, with anticipated climacteric. At climacteric, they have lower prolactin levels than normal controls (N/N). Because they are able to breast feed, we hypothesized that this prolactin reduction is limited to climacteric, as result of lower estradiol exposure of the lactotrophs. The purposes of this work were to assess prolactin levels in broader age adults homozygous and heterozygous (MUT/N) for the mutation and in normal controls (N/N), and correlate them with determinants factors and insulin sensitivity. We enrolled 24 GH-naıve MUT/MUT (12 female), 25 MUT/N (14 female), and 25 N/N (11 female) subjects, aged 25 65 years. Anthropometric data and serum prolactin, estradiol, total testosterone, and sex hormone binding globulin (SHBG) were measured. Free testosterone was calculated. Prolactin levels were similar in the threeg groups. In males, testosterone and SHBG levels were higher in MUT/MUT in comparison to N/N. There was no difference in free testosterone among groups. In all 74 individuals, prolactin correlated inversely with age (p.0001) and directly with serum estradiol (p = 0.018). Prolactin levels in subjects with IGHD due to a homozygous GHRHR mutation are similar to heterozygous and normal homozygous, but total testosterone and SHBG are higher in male MUT/MUT, with no difference in free testosterone. The reduced prolactin level is limited to climacteric period, possibly due to reduced estrogen exposure. / O hormônio do crescimento (GH) e a prolactina possuem fortes semelhanças em estrutura e função. Nós demonstramos que as mulheres com nanismo grave devido a deficiência isolada de GH (DIGH), causada por uma mutação homozigótica (c.57 + 1G > A) no gene do receptor de GHRH (MUT/MUT), apresentam uma vida reprodutiva curta, e no momento do climatério têm níveis mais baixos de prolactina do que os contrôles normais (N / N). O fato delas serem capazes de amamentar no menacne, sugeriu a hipótese de que esta redução da prolactina seria limitada a climatério como resultado da redução da menor exposição do estradiol aos lactotrofos. Os objetivos deste trabalho foi avaliar os níveis de prolactina em uma faixa etária mais ampla em indivíduos adultos homozigóticos afetados e heterozigoticos (MUT/N), e correlacioná-los com fatores determinantes e a sensibilidade a insulina. Para tal, um estudo transversal analítico incluiu 74 individuos de ambos os sexos, 24 MUT/MUT (12 mulheres), 25 MUT/N (14 mulheres) e 25 N/N (11 mulheres), com idades entre 25 e 62 anos. Foram obtidos os dados antropoméricos (peso, altura e IMC), os exames hormonais (prolactina sérica, estradiol, testosterona total e SHBG) dosados, sendo a a testosterona livre calculada. Os níveis de prolactina foram semelhantes entre os três grupos. Os níveis de testosterona total e SHBG em individuos do sexo masculino foram maiores no MUT/MUT em comparação com N/N e MUT/N (p < 0,0001 e p < 0,05), respectivamente. Não houve diferença nos níveis de testosterona livre entre os grupos e gêneros. Em todos os 74 indivíduos, a prolactina sérica correlacionou-se inversamente com a idade (p < 0,0001) e diretamente com estradiol (p = 0,018). Conclusões: Os níveis de prolactina nos individuos com DIGH devido a uma mutação homzigotica no GHRHR são semelhantes aos indivíduos heterozigóticos e homozigóticos normais, mas a testosterona total e SHBG são mais elevados nos individuos do sexo masculino no grupo MUT/MUT, sem diferença nos níveis de testosterona livre. O nível reduzido de prolactina é limitado ao periodo do climatério, possivelmente devido a menor exposicção estrogênica.
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