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Análise do gene KISS1 nos distúrbios puberais humanos / KISS1 gene analysis in patients with central pubertal disordersSilveira, Letícia Ferreira Gontijo 05 March 2009 (has links)
A kisspeptina, codificada pelo gene KISS1, é um neuropeptídeo crucial na regulação do início da puberdade. A kisspeptina estimula a secreção hipotalâmica do hormônio liberador de gonadotrofinas (GnRH) após se ligar ao seu receptor GPR54. Mutações inativadoras do GPR54 são atualmente consideradas como uma causa rara de hipogonadismo hipogonadotrófico isolado (HHI) normósmico. Recentemente, uma mutação ativadora no receptor GPR54 foi implicada na patogênese da puberdade precoce dependente de gonadotrofinas (PPDG). Com base nesses achados, levantamos a hipótese de que alterações no gene KISS1 poderiam contribuir para a patogênese de distúrbios puberais centrais. O objetivo do presente estudo foi investigar a presença de variantes no gene KISS1 em pacientes com PPDG e HHI. Sessenta e sete crianças brasileiras com PPDG (63 meninas e 4 meninos) e 61 pacientes com HHI (40 homens e 21 mulheres) foram selecionados, incluindo casos esporádicos e familiares em ambos os grupos. A população controle consistiu de 200 indivíduos com história de desenvolvimento puberal normal. A região promotora e os 3 exons do gene KISS1 foram amplificados e submetidos a sequenciamento automático. Duas novas variantes no gene KISS1, p.P74S e p.H90D, foram identificadas em duas crianças não relacionadas, portadoras de PPDG idiopática. Ambas as variantes estão localizadas na região amino-terminal da kisspeptina-54 e estavam ausentes em 400 alelos controles. A variante p.P74S foi identificada em heterozigose em um menino que desenvolveu puberdade com um ano de idade. Sua mãe e avó materna, que apresentavam história de desenvolvimento puberal normal, eram portadoras da mesma variante em heterozigose, sugerindo penetrância incompleta e/ou herança sexo-dependente. A variante p.H90D foi identificada em homozigose em uma menina com PPDG, que desenvolveu puberdade aos seis anos de idade. Sua mãe, com história de menarca aos dez anos de idade, era portadora da mesma variante em heterozigose. Células transfectadas estavelmente com GPR54 foram estimuladas com concentrações crescentes de kisspeptina-54 (kp-54) humana selvagem ou contendo as mutações (kp-54 H90D e kp-54 P74S) e o acúmulo de fosfato de inositol (IP) foi medido. Nos estudos in vitro, a kp-54 P74S apresentou uma capacidade de ativação do receptor GPR54 semelhante à kp-54 selvagem. A kp-54 p.H90D mostrou uma ativação da sinalização do receptor significativamente mais potente que a kp-54 selvagem, sugerindo que essa é uma mutação ativadora. No grupo de HHI, uma nova variante (c.588-589insT) foi identificada em heterozigose na região 3 não traduzida do gene KISS1 em um paciente do sexo masculino. O papel dessa variante no fenótipo de HHI permanece indeterminado. Em conclusão, duas mutações no gene KiSS1 foram descritas pela primeira vez em associação com PPDG. / Kisspeptin, encoded by the KISS1 gene, is an important regulator of puberty onset. After binding to its receptor GPR54, kisspeptin stimulates gonadotropin-releasing hormone secretion by the hypothalamic neurons. Inactivating GPR54 mutations are a rare cause of normosmic isolated hypogonadotropic hypogonadism (IHH). Recently, a unique GPR54 activating mutation was implicated in the pathogenesis of gonadotropin dependent precocious puberty (GDPP). Based on these observations, we hypothesized that mutations in the KISS1 gene might be associated with central pubertal disorders. The aim of this study was to investigate KISS1 mutations in idiopathic GDPP and normosmic IHH. Sixty-seven Brazilian children (63 girls and 4 boys) with idiopathic GDPP and 61 patients with normosmic IHH (40 men and 21 women) were selected. Familial and sporadic cases were included in both groups. The control population consisted of 200 individuals who had normal timing of puberty. The promoter region and the 3 exons of the KISS1 gene were amplified and automatically sequenced. Two novel KISS1 missense mutations, p.P74S and p.H90D, were identified in two unrelated children with idiopathic GDPP. Both mutations were absent in 400 control alleles and are located in the amino-terminal region of kisspeptin-54. The p.P74S mutation was identified in the heterozygous state in a boy who developed puberty at 1 yr of age. His mother and maternal grandmother, who had normal pubertal development, were also heterozygous for the p.P74S mutation, suggesting incomplete penetrance and/or sex-dependent inheritance. The p.H90D mutation was identified in the homozygous state in a girl with GDPP, who developed puberty at 6 yr of age. Her mother, who had menarche at 10 yr of age, carried the p.H90D mutation in the heterozygous state. CHO cells stably transfected with GPR54 were stimulated with different concentrations of synthetic human wild type or mutant kisspeptin-54 (KP54) and inositol phosphate (IP) accumulation was measured. In vitro studies revealed that the capacity of the p.P74S mutant KP54 to stimulate IP production was similar to the wild type. The p.H90D kisspeptin-54 showed a significantly more potent activation of GPR54 signaling in comparison to the wild type in vitro, suggesting a gain-of-function mutation. In the IHH group, a heterozygous variant in the 3 UTR of the KISS1 gene (c.588-589insT) was identified. The role of this variant in the IHH phenotype remains to be determined. In conclusion, two KiSS1 mutations were described for the first time in association with GDPP.
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Participação do hormônio liberador de corticotropina (CRH) e dos hormônios da pró-opiomelanocortina (POMC) no lúpus eritematoso sistêmico com envolvimento cutâneo / CRH and pro-opiomelanocortin (POMC) participation in systemic lupus erythematosus with skin involvementSchmitz, Monique Kowalski 03 December 2014 (has links)
Introdução: A ativação do eixo hormônio liberador de corticotropina (CRH) e da pró-opiomelanocortina (POMC) leva a produção de vários derivados bioativos que incluem o hormônio adrenocorticotrófico (ACTH) e o hormônio estimulador de melanócito alfa (alfa-MSH). Estudos avaliando a participação desse eixo no lúpus eritematoso sistêmico (LES) são escassos, particularmente no envolvimento cutâneo da doença. Objetivo: Avaliar a participação do CRH e das melanocortinas (MCs) na fisiopatologia do lúpus eritematoso sistêmico com envolvimento cutâneo. Métodos: Dezessete pacientes com LES com envolvimento cutâneo foram avaliados clinicamente e biópsias da pele afetada e não afetada e do sangue periférico foram obtidas. Dezessete indivíduos saudáveis foram pareados por idade e gênero. Os fragmentos de pele foram submetidos à análise imuno-histoquímica para avaliação da expressão de CRH, ACTH, alfaMSH, e receptor de melanocortina tipo 1 (MC-1R). Os níveis séricos de alfa-MSH, IL-1, IL-1ra, IL-6, IL-10, IL-12p70, IL-17, TNF-alfa, e IFN-y foram determinados pelo método Multiplex. Resultados: A pele afetada de pacientes com LES apresentaram maior expressão CRH na derme profunda quando comparada à pele não afetada dos mesmos doentes e a pele saudável dos controles (p = 0,024). Níveis séricos de alfa-MSH foram similares entre LES e controles. Dentre as citocinas avaliadas, IFN-y, TNF-alfa e IL-6 foram mais elevadas nos pacientes com LES em relação aos controles (p = 0,041, p = 0,001 e p = 0,049, respectivamente). Embora não significativamente, os níveis de IL-17 também foram mais altos nos pacientes (p = 0,099). A expressão tecidual de ACTH, cortisol, alfa-MSH e seu receptor MC-1R foram semelhantes entre os pacientes e controles. Conclusões: Nossos resultados mostram, pela primeira vez a participação do eixo CRH-POMC na patogênese das lesões cutâneas do LES / Introduction: Corticotropin-releasing hormone (CRH) and pro-opiomelanocortin (POMC) axis activation leads to the production of several bioactive hormones including adrenocorticotrophic hormone (ACTH) and the neuropeptide alfa-melanocyte stimulating hormone (alfa-MSH). There are scarce data regarding their role in systemic lupus erythematosus (SLE) particularly in cutaneous involvement of this disease. Objective: To evaluate the role of CRH and melanocortins (MCs) in the pathophysiology of systemic lupus erythematosus with skin involvement. Methods: Seventeen patients with SLE with skin involvement were evaluated clinically and biopsies of affected and unaffected skin and peripheral blood were obtained. Seventeen healthy subjects were matched for age and gender. The skin fragments were subjected to immunohistochemical analysis for the expression of CRH, ACTH, alfa-MSH and melanocortin receptor type 1 (MC-1R). Serum levels of alfa-MSH, IL-1, IL-1ra, IL-6, IL-10, IL-12p70, IL-17, TNF-alfa and IFN-y were determined by multiplex. Results: The affected skin of SLE patients exhibited greater CRH expression in the deep dermis compared to unaffected skin of the same patients and the control\'s healthy skin (p = 0.024). alfa-MSH were similar between SLE and controls. Among the evaluated cytokines, IFN-y, TNF-alfa and IL-6 were significantly higher in SLE patients compared to controls (p = 0.041, p = 0.001 and p = 0.049, respectively). Although not significant, levels of IL-17 were also higher in patients (p = 0.099). Tissue expression of ACTH, cortisol, alfa-MSH and its receptor MC-1R were similar between patients and controls. Conclusions: Our results show for the first time the involvement of CRH-POMC axis in the pathogenesis of SLE cutaneous lesions through interactions between the brain-skin axis
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O efeito do sistema intra-uterino de levonorgestrel (SIU-LNG) no fluxo das artérias uterinas, volume uterino e espessura endometrial em pacientes com endometriose pélvica: estudo comparativo com o análogo de GNRH (GnRHa) / The effect of System Intrauterine levonorgestrel (LNG-IUS) in the uterine artery flow, volume uterinoe Endometrial thickness in patients with endometriosis Pelvic: comparative study with the GnRH analogue (GnRHa)Manetta, Luiz Alberto 13 December 2007 (has links)
Objetivos: O objetivo deste estudo foi comparar os índices de Pulsatilidade (IP) e Resistência (IR) das artérias uterinas, o volume uterino e a espessura endometrial após o uso do Sistema Intra-uterino de Levonorgestrel (SIU-LNG) ou do agonista do GnRHa (GnRHa) em pacientes portadoras de endometriose pélvica. Pacientes e métodos: Setenta e nove mulheres voluntárias, com idade entre 18 e 40 anos, foram incluídas neste ensaio clínico comparativo, prospectivo, randomizado e controlado. Dezoito foram eliminadas do estudo baseadas nos critérios de exclusão, As 61 pacientes remanescentes foram divididas em dois grupos: 31 pacientes fizeram parte do grupo SIU-LNG (uma foi excluída antes da inserção por apresentar-se grávida) e 30 fizeram parte do grupo GnRHa. Foram submetidasa exame ultra-sonográfico transvaginal bidimensional no dia em que iniciaram o tratamento (inserção do SIU-LNG ou administração de uma ampola de 3,75 mg de GnRHa por via intra-muscular) e seis meses após, avaliando a espessura endometrial, o volume uterino e os IR e IP das artérias uterinas. Resultados: Ambos tratamentos promoveram redução da espessura endometrial (6.08±3.00mm para 2.70±0.98mm e 6.96±3.82mm para 3.23±2.32mm - média ±SD, grupo SIU-LNG e grupo GnRHa, respectivamente). O volume uterino teve redução no grupo usuário do GnRHa (86.67±28.38cm3 para 55.27±25.52cm3) sem alteração significativa nas usuárias do SIU-LNG (75.77±20.88cm3 para 75.97±26.62cm3). Em relação à ascularização uterina, notamos incremento dos IP das artérias uterinas em ambos os grupos (grupo SIU-LNG: artéria uterina direita de 2.38±0.72 para 2.76±0.99 (média ±SD) e artéria uterina esquerda 2.46±0.70 para 2.87±0.96, e grupo GnRHa: artéria uterina direita 2.04±0.59 para 3.12±0.98 eartéria uterina esquerda 2.24±0.59 para 3.15±0.89). Em relação ao IR das artérias uterinas, observamos incremento no grupo GnRHa em ambas artérias e somente na artéria uterina esquerda no grupo SIU-LNG (grupoSIU-LNG - artéria uterina direita de 0.85±0.08 para 0.88±0.07 e artéria uterina esquerda de 0.86±0.07 para 0.89±0.06, e grupo GnRHa: artéria uterina direita de 0.81±0.07 para 0.93±0.09 e artéria uterina esquerda 0.84±0.06 para 0.93±0.09). No entanto, ao compararmos as diferenças, a elevação foi significativamente maior nas usuárias do GnRHa. Conclusões: Ambos GnRHa e SIU-LNG promoveram redução na espessura endometrial e aumento no IP das artérias uterinas. Houve redução do volume uterino nas usuárias do grupo GnRHa, não se alterando no grupo SIU-LNG. Em relação ao IR, houve incremento em ambas as artérias nas usuárias de GnRHa e somente na artéria uterina esquerda nas usuárias do SIU-LNG. / Objectives:The objective of the present study was to compare the uterine arteries pulsatility index (PI) and resistence index (IR), uterine volume and endometrial thickness changes promoted by the use of the levonorgestrel intrauterine device (LNG-IUD) and the gonadotropin-releasing hormone analogue (GnRHa)in patients with endometriosis. Methods: Seventy nine women aged 18 to 40 years were included in this randomized controlled trial. Eighteen was excluded based on the exclusion criteria. The patients were randomly allocated in two groups: 31 women who used the LNG-IUD (since one became pregnant before insertion and wasexcluded) and 30 who used monthly GnRHa injections. They were submitted to a transvaginal two dimensional ultrasound scan on the day the treatment started and 6 months later, for the evaluation of uterine arteries PI, uterine arteries RI, uterine volume and endometrial thickness. Results: The use of LNG-IUD promoted an ndometrial thickness decrease (6.08±3.00mm to 2.7±0.98mm; mean±SD) as does the use of GnRHa (6.96±3.82mm to 3.23±2.32mm). The uterine volume decreased in the GnRHa group (86.67±28.38cm3to 55.27±25.52cm3), but not in the LNG-IUD group (75.77±20.88cm3 to 75.97±26.62cm3). Uterine arteries PI increased in both groups : Uterine arteries PI: LNG-IUD right uterine arterie 2.38 ± 0.72 to 2.76 ± 0.99 and left uterine arterie 2.46 ± 0.70 to 2.87 ± 0.96, and GnRHa right uterine arterie 2.04 ± 0.59 to 3.12 ± 0.98 and left uterine arterie 2.24±0.59 to 3.15 ± 0.89. Uterine arteries RI increased in both arteries in GnRHa and only in the left uterine arterie in the LNG-IUD :Uterine arteries RI : LNG-IUD right uterine arterie 0.85 ± 0..08 to 0.88 ± 0.07 and left uterine arterie 0.86 ± 0.07 to 0.89 ± 0.06, and GnRHa right uterine arterie 0.81 ± 0.07 to 0.93 ± 0.09 and left uterine arterie 0.84 ± 0.06 to 0.93 ± 0.09 . However, the increase was significant higher in the GnRHa group. Conclusions: Both GnRHa and LNG-IUD promoted an endometrial thickness decrease and an increase in the uterine arteries PI. The uterine volume decreased in women who used GnRHa, but not in those who used LNG-IUD.
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Cloning and characterization of follistatin in the goldfish, Carassius auratus.January 2003 (has links)
Cheng Fu Yip Gheorghe. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 97-116). / Abstracts in English and Chinese. / Acknowledgement --- p.I / Abstract (in English) --- p.III / Abstract (in Chinese) --- p.V / Table of Content --- p.VII / Symbols and Abbreviations --- p.XII / Scientific Names --- p.XIV / List of Tables --- p.XV / List of Figures --- p.XVI / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Gonadotropin / Chapter 1.1.1 --- Structure --- p.2 / Chapter 1.1.2 --- Function --- p.3 / Chapter 1.1.3 --- Regulation --- p.4 / Chapter 1.1.3.1 --- Neuroendocrine and endocrine regulation of GTHs --- p.4 / Chapter 1.1.3.1.1 --- Hypothalamic neuropeptides and neurotransmitters --- p.6 / Chapter 1.1.3.1.2 --- Gonadal steroids --- p.7 / Chapter 1.1.3.2 --- Paracrine regulation of GTH --- p.8 / Chapter 1.2 --- Activin / Chapter 1.2.1 --- Structure --- p.8 / Chapter 1.2.2 --- Function --- p.9 / Chapter 1.2.3 --- Regulation of activin activity --- p.12 / Chapter 1.2.3.1 --- Intracellular blockade of activin signaling by Smad7 --- p.12 / Chapter 1.2.3.2 --- Extracellular control of activin access --- p.13 / Chapter 1.2.3.2.1 --- Inhibin --- p.13 / Chapter 1.2.3.2.2 --- Activin-binding protein --- p.14 / Chapter 1.3 --- Follistatin / Chapter 1.3.1 --- Structure --- p.14 / Chapter 1.3.2 --- Function --- p.16 / Chapter 1.3.3 --- Regulation in the pituitary --- p.19 / Chapter 1.4 --- Objectives of the Present Study --- p.20 / Chapter Chapter 2 --- Cloning and Recombinant Production of Goldfish Follistatin / Chapter 2.1 --- Introduction --- p.24 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Reagents --- p.26 / Chapter 2.2.2 --- Animal --- p.26 / Chapter 2.2.3 --- Extraction of total RNA and reverse transcription --- p.27 / Chapter 2.2.4 --- Cloning of full-length cDNA encoding goldfish follistatin --- p.27 / Chapter 2.2.5 --- Sequencing of the cDNA --- p.29 / Chapter 2.2.6 --- Distribution of follistatin mRNA in different tissues --- p.29 / Chapter 2.2.7 --- Production of rgFS --- p.30 / Chapter 2.2.8 --- RT-PCR of the rgFS-positive clones --- p.34 / Chapter 2.2.9 --- Extraction of genomic DNA from rgFS-positive clones --- p.34 / Chapter 2.2.10 --- Functional analysis of rgFS --- p.35 / Chapter 2.2.11 --- Data Analysis --- p.37 / Chapter 2.3 --- Results / Chapter 2.3.1 --- Cloning and sequence analysis of goldfish follistatin --- p.37 / Chapter 2.3.2 --- Tissue distribution of follistatin mRNA in the goldfish --- p.39 / Chapter 2.3.3 --- Production and bioassay of rgFS --- p.43 / Chapter 2.4 --- Discussion --- p.47 / Chapter Chapter 3 --- Function and Regulation of Follistatin in the Goldfish Pituitary; Evidence for an Intrinsic Activin/Follistatin Regulatory Feedback Loop / Chapter 3.1 --- Introduction --- p.54 / Chapter 3.2 --- Materials and Methods / Chapter 3.2.1 --- Reagents --- p.57 / Chapter 3.2.2 --- Animals --- p.57 / Chapter 3.2.3 --- Primary culture of dispersed pituitary cells --- p.57 / Chapter 3.2.4 --- RNA extraction and reverse transcription --- p.58 / Chapter 3.2.5 --- Ovariectomy on pituitary follistatin expression --- p.5 9 / Chapter 3.2.6 --- Seasonal expression profile of follistatin --- p.59 / Chapter 3.2.7 --- Validation of semi-quantitative RT-PCR assays --- p.61 / Chapter 3.2.8 --- Real-time PCR for assay on follistatin and β-actin expression --- p.61 / Chapter 3.2.9 --- Data analysis --- p.63 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Expression of follistatin in the goldfish pituitary --- p.64 / Chapter 3.3.2 --- Validation of semi-quantitative RT-PCR assay --- p.64 / Chapter 3.3.3 --- Activin regulation of pituitary follistatin --- p.64 / Chapter 3.3.4 --- Effects of sex steroids on pituitary follistatin expression --- p.69 / Chapter 3.3.5 --- Effect of GnRH on follistatin expression in the pituitary --- p.74 / Chapter 3.3.6 --- Effect of intracellular cAMP level on pituitary follistatin expression --- p.74 / Chapter 3.3.7 --- Seasonal variation profile of goldfish pituitary follistatin --- p.78 / Chapter 3.4 --- Discussion --- p.78 / Chapter Chapter 4 --- General Discussion / Chapter 4.1 --- Overview --- p.89 / Chapter 4.2 --- Contribution of the Present Study / Chapter 4.2.1 --- Cloning of full-length goldfish follistatin cDNA --- p.91 / Chapter 4.2.2 --- Establishment of stable cell line for expression of rgFS --- p.92 / Chapter 4.2.3 --- Evidence for the presence of intrinsic feedback loop of activin in the goldfish pituitary --- p.92 / Chapter 4.2.4 --- Modulation of follistatin expression in the pituitary by sex steroids --- p.93 / Chapter 4.2.5 --- Conclusions --- p.93 / Chapter 4.3 --- Future Prospects / Chapter 4.3.1 --- Production of rgFS --- p.95 / Chapter 4.3.2 --- Regulation of activin-follistatin system in the pituitary --- p.95 / Reference --- p.96
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Participação do hormônio liberador de corticotropina (CRH) e dos hormônios da pró-opiomelanocortina (POMC) no lúpus eritematoso sistêmico com envolvimento cutâneo / CRH and pro-opiomelanocortin (POMC) participation in systemic lupus erythematosus with skin involvementMonique Kowalski Schmitz 03 December 2014 (has links)
Introdução: A ativação do eixo hormônio liberador de corticotropina (CRH) e da pró-opiomelanocortina (POMC) leva a produção de vários derivados bioativos que incluem o hormônio adrenocorticotrófico (ACTH) e o hormônio estimulador de melanócito alfa (alfa-MSH). Estudos avaliando a participação desse eixo no lúpus eritematoso sistêmico (LES) são escassos, particularmente no envolvimento cutâneo da doença. Objetivo: Avaliar a participação do CRH e das melanocortinas (MCs) na fisiopatologia do lúpus eritematoso sistêmico com envolvimento cutâneo. Métodos: Dezessete pacientes com LES com envolvimento cutâneo foram avaliados clinicamente e biópsias da pele afetada e não afetada e do sangue periférico foram obtidas. Dezessete indivíduos saudáveis foram pareados por idade e gênero. Os fragmentos de pele foram submetidos à análise imuno-histoquímica para avaliação da expressão de CRH, ACTH, alfaMSH, e receptor de melanocortina tipo 1 (MC-1R). Os níveis séricos de alfa-MSH, IL-1, IL-1ra, IL-6, IL-10, IL-12p70, IL-17, TNF-alfa, e IFN-y foram determinados pelo método Multiplex. Resultados: A pele afetada de pacientes com LES apresentaram maior expressão CRH na derme profunda quando comparada à pele não afetada dos mesmos doentes e a pele saudável dos controles (p = 0,024). Níveis séricos de alfa-MSH foram similares entre LES e controles. Dentre as citocinas avaliadas, IFN-y, TNF-alfa e IL-6 foram mais elevadas nos pacientes com LES em relação aos controles (p = 0,041, p = 0,001 e p = 0,049, respectivamente). Embora não significativamente, os níveis de IL-17 também foram mais altos nos pacientes (p = 0,099). A expressão tecidual de ACTH, cortisol, alfa-MSH e seu receptor MC-1R foram semelhantes entre os pacientes e controles. Conclusões: Nossos resultados mostram, pela primeira vez a participação do eixo CRH-POMC na patogênese das lesões cutâneas do LES / Introduction: Corticotropin-releasing hormone (CRH) and pro-opiomelanocortin (POMC) axis activation leads to the production of several bioactive hormones including adrenocorticotrophic hormone (ACTH) and the neuropeptide alfa-melanocyte stimulating hormone (alfa-MSH). There are scarce data regarding their role in systemic lupus erythematosus (SLE) particularly in cutaneous involvement of this disease. Objective: To evaluate the role of CRH and melanocortins (MCs) in the pathophysiology of systemic lupus erythematosus with skin involvement. Methods: Seventeen patients with SLE with skin involvement were evaluated clinically and biopsies of affected and unaffected skin and peripheral blood were obtained. Seventeen healthy subjects were matched for age and gender. The skin fragments were subjected to immunohistochemical analysis for the expression of CRH, ACTH, alfa-MSH and melanocortin receptor type 1 (MC-1R). Serum levels of alfa-MSH, IL-1, IL-1ra, IL-6, IL-10, IL-12p70, IL-17, TNF-alfa and IFN-y were determined by multiplex. Results: The affected skin of SLE patients exhibited greater CRH expression in the deep dermis compared to unaffected skin of the same patients and the control\'s healthy skin (p = 0.024). alfa-MSH were similar between SLE and controls. Among the evaluated cytokines, IFN-y, TNF-alfa and IL-6 were significantly higher in SLE patients compared to controls (p = 0.041, p = 0.001 and p = 0.049, respectively). Although not significant, levels of IL-17 were also higher in patients (p = 0.099). Tissue expression of ACTH, cortisol, alfa-MSH and its receptor MC-1R were similar between patients and controls. Conclusions: Our results show for the first time the involvement of CRH-POMC axis in the pathogenesis of SLE cutaneous lesions through interactions between the brain-skin axis
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In vivo βιολογική αξιολόγηση και φαρμακοκινητική μελέτη με χρήση HPLC-MS-MS του Leuprolide και αναλόγων του που εμπλέκονται στη θεραπεία του καρκίνου / In vivo biological evaluation and pharmacokinetic studies of Leuprolide and analogues in the treatment of cancer, using HPLC-MS-MSΚατσίλα, Θεοδώρα 12 January 2012 (has links)
Ιστορικά, τα ευρήματα των C.B. Huggins (Huggins and Hodges, 1941; Huggins, 1963) και A.V. Schally (Schally et al., 1984) αποτέλεσαν την απαρχή μιας ερευνητικής πορείας με αφετηρία το πεδίο της νευροενδοκρινολογίας και προορισμό εκείνα της γυναικολογίας και της ογκολογίας. Η γνώση αναφορικά με τη φυσιολογία της ενδογενούς ορμόνης (LHRH) και το ρόλο της στην παθοβιοχημεία των ασθενειών (ενδοκρινικών διαταραχών και ορμονο – εξαρτώμενων καρκίνων) και υπό το πρίσμα της πρωτεύουσας ή υποστηρικτικής θεραπευτικής προσέγγισης, κατέστησε τον ιατρικό ευνουχισμό μέσω της δράσης στον υποδοχέα της LHRH – Ι στρατηγική επιλογής για την καταπολέμηση των ενδοκρινικών διαταραχών και των ορμονο – εξαρτώμενων καρκίνων (καρκίνος του μαστού, καρκίνος των ωοθηκών, καρκίνος του ενδομητρίου, καρκίνος του προστάτη). Μια πληθώρα αναλόγων της LHRH έδωσε και δίνει το παρόν σε προκλινικό και κλινικό επίπεδο, με τη συστηματική έρευνα, σύνθεση και ανάπτυξη να αποδίδουν μόρια – αγωνιστές ή – ανταγωνιστές του υποδοχέα της LHRH – Ι, πεπτιδικής (γραμμική ή κυκλική δομή, stapled peptides) ή μη φύσης ως μοναδιαίες οντότητες ή σε σύζευξη με ένα ευρύ φάσμα κυτταροτοξικών μορίων (Αnderes et al., 2003; Keramida et al., 2006; Persson et al., 2009; Kritzer, 2010; Mezo and Manea, 2010).
Η παρούσα διδακτορική διατριβή αποσκοπεί στην in vitro και in vivo αξιολόγηση και φαρμακοκινητική μελέτη καινοτόμων αναλόγων της LHRH – κυκλικής και γραμμικής δομής – στη βάση του ορθολογικού μοριακού σχεδιασμού και αποσκοπώντας σε εναλλακτικές προσεγγίσεις για την καταπολέμηση του καρκίνου του προστάτη (και έτερων ενδοκρινικών διαταραχών), συγκριτικά με το leuprolide (εμπορικά διαθέσιμος αγωνιστής του υποδοχέα της LHRH – Ι). Η παρούσα διδακτορική διατριβή θέτει ως υπόθεση εργασίας πως καινοτόμα ανάλογα της LHRH των ήδη υπάρχοντων στην κλινική με βελτιωμένο φαρμακοκινητικό προφίλ δύναται να αποτελέσουν τη βάση βέλτιστων εναλλακτικών θεραπευτικών προσεγγίσεων με ενισχυμένη αποτελεσματικότητα και μειωμένη τοξικότητα, δρώντας in situ ή/ και προσφέροντας νέες δυνατότητες χορήγησης, εστιάζοντας στην οδό ή/ και τη μείωση της συχνότητας αυτής. Η εν λόγω ερευνητική προσέγγιση εστιάζει στον καρκίνο του προστάτη, μια νόσο που χρήζει εναλλακτικής θεραπευτικής στρατηγικής, δεδομένης της χαμηλής αποτελεσματικότητας αυτής (η νόσος προοδευτικά γίνεται ανεξάρτητη των ορμονών και συνεπώς, μεταστατική), αλλά και της χαμηλής ποιότητας ζωής των ασθενών στη βάση του «συμβιβασμού» με τις οδούς χορήγησης που εφαρμόζονται σήμερα στην κλινική (depot formulations).
Επιπρόσθετα και κατά την εκπόνηση της εν λόγω ερευνητικής προσέγγισης αναπτύχθηκαν, επικυρώθηκαν και βελτιστοποιήθηκαν καινοτόμες μεθοδολογίες υγρής χρωματογραφίας – φασματομετρίας μάζας (LC – MS/ MS) σε βιολογικά υγρά – ηπατικά μικροσώματα (μύα, επίμυα, ανθρώπου), νεφρικές μεμβράνες μύα, πλάσμα και όρχεις μύα – και έτερα υποστρώματα (κυτταρικά εκχυλίσματα, υδάτινο περιβάλλον ιχθύων Danio rerio), οι οποίες, εν συνεχεία, συζεύχθηκαν με in vitro ή/ και in vivo βιοδοκιμασίες. Τα πειραματικά ευρήματα συγκρίθηκαν με εκείνα των εμπορικά διαθέσιμων αναλόγων της LHRH, με αγωνιστική (leuprolide) ή ανταγωνιστική δράση (antide, cetrorelix).
Πιο αναλυτικά και λαμβάνοντας υπόψην το «νοσηρό» φαρμακοκινητικό προφίλ των αναλόγων της LHRH που χρησιμοποιούνται σήμερα στην κλινική, διερευνήθηκε η in vitro (ηπατικά μικροσώματα μύα, επίμυα και ανθρώπου – νεφρικές μεμβράνες μύα) και in vivo (πλάσμα μύα) πεπτιδική σταθερότητα των υπό μελέτη αναλόγων, συγκριτικά με την LHRH και εμπορικά διαθέσιμα ανάλογα αυτής (antide, leuprolide). Τα ευρήματα επέτρεψαν την αξιολόγηση και ταξινόμηση των αναλόγων του ενδιαφέροντος βάσει πεπτιδικής σταθερότητας (δοκιμασία σάρωσης). Ταυτόχρονα, προσδιορίστηκε το μεταβολικό τους προφίλ, αποκαλύπτοντας τους ευάλωτους πεπτιδικούς δεσμούς, καθώς και τις εμπλεκόμενες ενδοπεπτιδάσες (NEP – EC 3.4.24.11, ACE – EC 3.4.15.1). Τα ευρήματα επιβεβαιώθηκαν περαιτέρω με τη χρήση ειδικών ενζυμικών αναστολέων (ενδεικτικά: DL – Thiorphan). Ο νεφρός βρέθηκε να είναι το πρωτεύον μεταβολικό όργανο. Η ανίχνευση και η ημι – ποσοτικοποίηση των μεταβολικών προϊόντων οδήγησε στον προσδιορισμό σχέσεων δομής – δραστικότητας, αποτελώντας τη βάση του ορθολογικού σχεδιασμού καινοτόμων μορίων. Οι απορρέουσες σχέσεις δομής –δραστικότητας υποστηρίζουν πως (i) η μεθυλίωση της υδροξυλομάδας της Tyr5, (ii) η αντικατάσταση της Pro9 από Aze και (iii) η κυκλοποίηση ενισχύουν την πεπτιδική σταθερότητα των αναλόγων του ενδιαφέροντος.
Στα πλαίσια μελετών φαρμακοδυναμικής, αναπτύχθηκε καινοτόμος μεθοδολογία LC – MS/ MS για τον ταυτόχρονο ποσοτικό προσδιορισμό της τεστοστερόνης και των υπό μελέτη αναλόγων σε πλάσμα (0, 05 – 100 ng/mL) και όρχεις μύα (2, 0 – 2000 ng/g). Η τεστοστερόνη θεσπίστηκε βιοδείκτης αποτελεσματικότητας (efficacy) και τοξικότητας (toxicity) στη βάση του καίριου ρόλου που διαδραματίζει το εν λόγω στεροειδές στη φυσιολογία του άξονα υποθάλαμος – υπόφυση – γονάδες και την παθοβιοχημεία των ενδοκρινικών διαταραχών και του ορμονο – εξαρτώμενου καρκίνου του προστάτη. Η φαρμακολογική απόκριση (απελευθέρωση τεστοστερόνης) βρέθηκε πως είναι ειδική και λαμβάνει χώρα μέσω του υποδοχέα της LHRH – Ι. Πιο σημαντικά, επετεύχθη ιατρικός ευνουχισμός, βάσει ιστοπαθολογικών ευρημάτων και προσδιορισμού της τεστοστερόνης (πλάσμα και όρχεις μύα), κατόπιν επαναλαμβανόμενης ενδοπεριτοναϊκής χορήγησης του επιλεγμένου καινοτόμου γραμμικού αναλόγου της LHRH, linearGnRH1. Το ίδιο ανάλογο βρέθηκε να έχει κυτταροστατική δράση σε πειράματα κυτταρικού πολλαπλασιασμού (κύτταρα LNCaP και PC3). Παράλληλα και υπό το πρίσμα του ρόλου της LHRH στην παθοβιοχημεία έτερων ορμονο – εξαρτώμενων καρκίνων (καρκίνος του μαστού, καρκίνος των ωοθηκών, καρκίνος του ενδομητρίου), αναπτύχθηκε, επικυρώθηκε και βελτιστοποιήθηκε καινοτόμος μεθοδολογία LC – MS/ MS για τον ποσοτικό προσδιορισμό της 17β – οιστραδιόλης σε βιολογικά υγρά. Τέλος, αναπτύχθηκε καινοτόμος μεθοδολογία LC – MS/MS για τον ποσοτικό προσδιορισμό πεπτιδίων του ενδιαφέροντος στο υδάτινο περιβάλλον των ιχθύων του είδους Danio rerio.
Το καινοτόμο γραμμικό ανάλογο της LHRH, linearGnRH1, δεδομένου του φαρμακοκινητικού/ φαρμακοδυναμικού του προφίλ, δρα υποστηρικτικά ως προς την υπόθεση της παρούσας διδακτορικής διατριβής, σύμφωνα με την οποία καινοτόμα ανάλογα των ήδη υπάρχοντων στην κλινική με βελτιωμένο φαρμακοκινητικό προφίλ δύναται να αποτελέσουν τη βάση βέλτιστων εναλλακτικών θεραπευτικών προσεγγίσεων με ενισχυμένη αποτελεσματικότητα και μειωμένη τοξικότητα, δρώντας in situ ή/ και προσφέροντας νέες δυνατότητες χορήγησης, εστιάζοντας στην οδό ή/ και τη μείωση της συχνότητας αυτής. Το linearGnRH1 δύναται να αποτελέσει τη βάση για τον ορθολογικό σχεδιασμό μορίων (stapled peptides, μιμητές), αποσκοπώντας σε εναλλακτικές θεραπευτικές στρατηγικές για την καταπολέμηση του ορμονο – εξαρτώμενου καρκίνου ή/ και των ενδοκρινικών διαταραχών. Πέραν του linearGnRH1, ας σημειωθεί πως κατά την εκπόνηση της παρούσας διδακτορικής διατριβής συγκεκριμένα καινοτόμα κυκλικά ανάλογα της LHRH (cyclicGnRH1, cyclicGnRH2, cyclicGnRHDL1, cyclicGnRHDL2) εμφάνισαν ένα διακριτό φαρμακοκινητικό προφίλ. Το φαρμακοδυναμικό προφίλ των εν λόγω κυκλικών πεπτιδίων απαιτείται να διερευνηθεί περαιτέρω με την εφαρμογή των καινοτόμων μεθοδολογιών LC – MS/MS που αναπτύχθηκαν, επικυρώθηκαν και βελτιστοποιήθηκαν κατά την εκπόνηση της παρούσας διδακτορικής διατριβής.
Συνολικά, η καινοτομία της εν λόγω ερευνητικής προσέγγισης έγκειται (i) στην ανάπτυξη, επικύρωση και βελτιστοποίηση ενός πλήθους μεθοδολογιών LC – MS/MS σε σύζευξη με in vitro και in vivo βιοδοκιμασίες, οι οποίες και αποτελούν ένα διακριτό αναλυτικό εργαλείο και (ii) στο προκλινικό φαρμακολογικό μοντέλο που αναπτύχθηκε με την επιλογή του μύα ως ζωικό πρότυπο. Κοινή συνισταμένη, η εν τω βάθει αξιολόγηση της φαρμακοκινητικής/ φαρμακοδυναμικής των πεπτιδίων του ενδιαφέροντος με το ερευνητικό βλέμμα στα πεπτιδικά φάρμακα.. stapled peptides.. μιμητές.. / The highly influential findings of C. B. Huggins (Huggins, 1963) and A. V. Schally (Schally et al., 1984) brought a new era in the research fields of neuroendocrinology, gynecology and oncology. The knowledge acquired regarding the physiology of LHRH and its role in the pathobiochemistry of the disease resulted in the consideration of medical castration via the LHRH receptor as a well established strategy for the treatment of endocrine disorders (e.g. precocious puberty) and hormone – dependent cancers (breast cancer, endometrial cancer, prostate cancer). Numerous LHRH analogues have been synthesized and evaluated both in the clinic and preclinical level. Overall, systematic work has resulted in the synthesis of LHRH receptor agonists and antagonists, either peptides (linear, cyclic, stapled peptides) or small organic molecules as entities or combined with various cytotoxic molecules (Αnderes et al., 2003; Keramida et al., 2006; Persson et al., 2009; Kritzer, 2010; Mezo and Manea, 2010).
Although extensive research has been carried out in the field of hormonal therapy, poor pharmacokinetic properties still characterize LHRH peptide analogues. Poor stability of LHRH analogues compromises efficacy, while the need for their subcutaneous administration (depot formulations) aggravates the quality of life for cancer patients. Nowadays, LHRH analogues in the clinic most likely achieve the desired pharmacologic effects by action primarily on the pituitary and to a much lesser extent by direct antiproliferative effects on tumor cells.
Herein, we hypothesize that stable analogues of such super – agonists would be advantageous, either by allowing a reduction in dosing frequency or by allowing the use of analogues that act directly on the tumor, with possible additive effects and subsequent enhancements in efficacy. In this context, the pharmacokinetic/ pharmacodynamic profiles of novel LHRH analogues were determined both in vitro and in vivo. Similarly, commercially available LHRH analogues (leuprolide, antide, cetrorelix) served as positive controls.
Novel LC – MS/MS based approaches (LC – MS/ MS methodologies coupled to in vitro and in vivo bioassays) were developed, validated and optimized for the evaluation of the peptide analogues in question (linear or cyclic) in various biological fluids and matrices; (i) mouse, rat and human liver microsomes, (ii) mouse kidney membrane preparations, (iii) mouse plasma and tissue (testis), (iv) egg – water (Danio rerio embryos environment). Furthermore, a novel LC – MS/MS based approach was developed, validated and optimized for the simultaneous quantification of testosterone and peptides in question, upon the intraperitoneal administration of peptide analogues in mice. Testosterone served as an efficacy and toxicity biomarker. Peptide metabolism was thoroughly studied by an LC – MS/MS based approach coupled to an in vitro bioassay (mouse kidney membrane preparations), allowing (i) structural elucidation and semi – quantitation of metabolites (and peptides) as a function of time, (ii) determination of the susceptible to proteolysis peptide – bonds, (iii) structure – activity relationships (SARs) and (iv) peptide ranking (screening assay). Taking into account the role of LHRH in gynecology and hormone – dependent cancers of breast, endometrium and ovary, an LC – MS/MS based approach was developed for the quantification of 17β – oestradiol (efficacy and toxicity biomarker) in mouse plasma upon the intraperitoneal administration of peptide analogues in mice. A novel LC – MS/MS based approach was also developed for the quantification of peptides of interest in the aquatic environment of Danio rerio.
Employing the aforementioned analytical tools, peptide stability against proteolysis was evaluated both in vitro (mouse kidney membrane preparations) and in vivo (mouse plasma). LHRH and commercially available analogues served as positive controls. The SARs derived suggested that enhanced stability was achieved by (i) methylation on the hydroxyl group of Tyr5, (ii) replacement of Pro9 by Aze and (iii) cyclisation. Hence, new promising chemical entities could be synthesized and developed on the basis of rational drug design. Metabolic profiles were also determined revealing the susceptible to proteolysis peptide bonds. Susceptible peptide bonds and endopeptidases involved were further confirmed in the presence of specific endopeptidase inhibitors.
A facile preclinical mouse model was developed in the context of our objectives. Intraperitoneal administration was selected, since (i) it is a mix – mode type of administration with elements of rapid absorption and (ii) oral administration was not practical due to the low bioavailability of the peptides that were tested. The LC – MS/MS based quantification of the selected bioactive peptides and their corresponding metabolites as well as the selective monitoring of biomarkers (e.g. testosterone) in response to drug dose, in plasma and testes, combined with the appropriate preclinical mouse model, represents a distinctive approach. The mouse model described in this paper is particularly valuable, since (i) the human LHRH receptor is homologous to the mouse receptor (Millar, 2004), (ii) information on in vitro and in vivo stability can be obtained with a relatively small amount of peptide (1 – 2 mg), (iii) information on the LHRH receptor agonism (receptor specific in vivo modulation) can be obtained by using testosterone as a marker, (iv) it allows the determination of the dosing regimen required for efficacy based on action on the pituitary, (v) it can become the basis of follow up experiments on genetically modified mouse animal models or other tumour xenografted mouse models (Sharpless and Depinho, 2006; Morgan et al., 2008).
The robust sensitive methodology that was developed for the quantification of testosterone in mouse plasma (0.05 – 100 ng/mL) or determination of testosterone in testes (2 – 2000 ng/g) provides an excellent handle on compound efficacy assessment. Testosterone as an efficacy and toxicity biomarker was found to be specific upon peptide binding to the LHRH receptor. Medical castration was achieved upon the repeated dosing of a selected novel linear analogue (linearGnRH1). Measurements in plasma were further supported by statistical significant testosterone values in testis and histopathological findings (atrophy). Moreover the testis weights of the treated animals were significantly lower in comparison to the control group (atrophy induced by dosing), thus making the differences in testosterone testis concentration between control and peptide treated animals even more pronounced. Although the binding affinity of linearGnRH1 on the LHRH receptor was not as high as the binding affinity of leuprolide (~ 15 nM versus <1 nM), the in vivo efficacy between the two analogues was similar (at the tested dose), suggesting that the enhanced stability or bioavailability of linearGnRH1, compensates for binding affinity differences. LinearGnRH1 was also found to be anti – proliferative upon dosing in LNCaP cells (as potent as the superagonist leuprolide). It is possible that linearGnRH1 can play a significant role for the treatment of hormone – dependent cancers, by acting not only at the pituitary level (thus, suppressing the pituitary – testicular axis), but also by exerting an antitumor activity directly on cancer cells, as has been previously shown for other LHRH agonists (Maudsley et al., 2004; Marelli et al., 2006). Except for linearGnRH1, selected cyclic analogues (cyclicGnRH1, cyclicGnRH2, cyclicGnRHDL1, cyclicGnRHDL2) exhibited a distinct pharmacokinetic profile. Their pharmacodynamic profiles should be evaluated further employing the novel LC – MS/MS based approaches developed and validated in this study.
Overall, the novelty of the approach described herein consists of (i) the LC – MS/MS methodologies coupled with in vitro and in vivo bioassays developed, validated and employed that provide a distinct analytical tool and (ii) the facile preclinical pharmacological mouse model developed and employed. The approach aims to the pharmacokinetic/pharmacodynamic evaluation of the peptides of interest towards a new generation of peptide drugs.. stapled peptides.. mimetics. Considering the pharmacokinetic/ pharmacodynamic profiles of linearGnRH1, findings on this novel analogue satisfy our hypothesis according to which stable analogues of the LHRH super – agonists used in the clinic would be advantageous, either by allowing a reduction in dosing frequency or by allowing the use of analogues that act directly on the tumor, with possible additive effects and subsequent enhancements in efficacy. LinearGnRH1 can serve as the platform for the rational drug design of new chemical entities (stapled peptides, mimetics) for the treatment of hormone – dependent cancers and/ or endocrine disorders.
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Estresse por derrota social intermitente em ratos Wistar machos : revisão e modulação farmacológica experimental do sistema CRFVasconcelos, Mailton França de January 2018 (has links)
O neuropeptídeo/hormônio CRF integra respostas de estresse a nível endócrino, imunológico e comportamental dos mamíferos. A atividade neuronal CRFérgica inapropriada pode estar por trás do aparecimento de sintomas associados a transtornos neuropsiquiátricos. Os experimentos apresentados nesta tese descrevem a modulação farmacológica de ligantes de CRF que compõem o sistema CRFérgico em ratos Wistar machos submetidos ao protocolo de estresse por derrota social. A experiência de episódios intermitentes à derrota social prejudicou o comportamento de interação social. Microinjeções de antagonista da proteína ligante de CRF e antagonista (CRF6-33) e antagonista específico do receptor de CRF do tipo 1 (CP316311) no núcleo intersticial da estria terminal, separadamente, restauraram a aproximação social em animais estressados. Esses achados sugerem que o conteúdo de CRF no núcleo intersticial da estria terminal está envolvido na modulação de respostas relacionadas à ansiedade induzidas pelo estresse social. / The CRF neuropeptide/hormone integrates endocrine, immune and behavioral stress responses of mammals. Inappropriate CRFergic neuronal activity may underlie the appearance of symptoms associated with neuropsychiatric disorders. The experiments presented in this dissertation describe the pharmacological modulation of CRF ligands composing the CRFergic system in male Wistar rats submitted to the social defeat stress protocol. The experience of intermittent episodes of social defeat disrupted behaviors of social interaction. Microinjections of an antagonist of CRF binding protein (CRF6-33) and specific antagonist of CRF receptor type 1 (CP316311) in the bed nucleus of stria terminalis, separately, restored the social approach behavior in stressed animals. These findings suggest that the CRF content in the bed nucleus of stria terminalis is involved in the modulation of anxiety-related responses induced by social stress.
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Estresse por derrota social intermitente em ratos Wistar machos : revisão e modulação farmacológica experimental do sistema CRFVasconcelos, Mailton França de January 2018 (has links)
O neuropeptídeo/hormônio CRF integra respostas de estresse a nível endócrino, imunológico e comportamental dos mamíferos. A atividade neuronal CRFérgica inapropriada pode estar por trás do aparecimento de sintomas associados a transtornos neuropsiquiátricos. Os experimentos apresentados nesta tese descrevem a modulação farmacológica de ligantes de CRF que compõem o sistema CRFérgico em ratos Wistar machos submetidos ao protocolo de estresse por derrota social. A experiência de episódios intermitentes à derrota social prejudicou o comportamento de interação social. Microinjeções de antagonista da proteína ligante de CRF e antagonista (CRF6-33) e antagonista específico do receptor de CRF do tipo 1 (CP316311) no núcleo intersticial da estria terminal, separadamente, restauraram a aproximação social em animais estressados. Esses achados sugerem que o conteúdo de CRF no núcleo intersticial da estria terminal está envolvido na modulação de respostas relacionadas à ansiedade induzidas pelo estresse social. / The CRF neuropeptide/hormone integrates endocrine, immune and behavioral stress responses of mammals. Inappropriate CRFergic neuronal activity may underlie the appearance of symptoms associated with neuropsychiatric disorders. The experiments presented in this dissertation describe the pharmacological modulation of CRF ligands composing the CRFergic system in male Wistar rats submitted to the social defeat stress protocol. The experience of intermittent episodes of social defeat disrupted behaviors of social interaction. Microinjections of an antagonist of CRF binding protein (CRF6-33) and specific antagonist of CRF receptor type 1 (CP316311) in the bed nucleus of stria terminalis, separately, restored the social approach behavior in stressed animals. These findings suggest that the CRF content in the bed nucleus of stria terminalis is involved in the modulation of anxiety-related responses induced by social stress.
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Análise do gene KISS1 nos distúrbios puberais humanos / KISS1 gene analysis in patients with central pubertal disordersLetícia Ferreira Gontijo Silveira 05 March 2009 (has links)
A kisspeptina, codificada pelo gene KISS1, é um neuropeptídeo crucial na regulação do início da puberdade. A kisspeptina estimula a secreção hipotalâmica do hormônio liberador de gonadotrofinas (GnRH) após se ligar ao seu receptor GPR54. Mutações inativadoras do GPR54 são atualmente consideradas como uma causa rara de hipogonadismo hipogonadotrófico isolado (HHI) normósmico. Recentemente, uma mutação ativadora no receptor GPR54 foi implicada na patogênese da puberdade precoce dependente de gonadotrofinas (PPDG). Com base nesses achados, levantamos a hipótese de que alterações no gene KISS1 poderiam contribuir para a patogênese de distúrbios puberais centrais. O objetivo do presente estudo foi investigar a presença de variantes no gene KISS1 em pacientes com PPDG e HHI. Sessenta e sete crianças brasileiras com PPDG (63 meninas e 4 meninos) e 61 pacientes com HHI (40 homens e 21 mulheres) foram selecionados, incluindo casos esporádicos e familiares em ambos os grupos. A população controle consistiu de 200 indivíduos com história de desenvolvimento puberal normal. A região promotora e os 3 exons do gene KISS1 foram amplificados e submetidos a sequenciamento automático. Duas novas variantes no gene KISS1, p.P74S e p.H90D, foram identificadas em duas crianças não relacionadas, portadoras de PPDG idiopática. Ambas as variantes estão localizadas na região amino-terminal da kisspeptina-54 e estavam ausentes em 400 alelos controles. A variante p.P74S foi identificada em heterozigose em um menino que desenvolveu puberdade com um ano de idade. Sua mãe e avó materna, que apresentavam história de desenvolvimento puberal normal, eram portadoras da mesma variante em heterozigose, sugerindo penetrância incompleta e/ou herança sexo-dependente. A variante p.H90D foi identificada em homozigose em uma menina com PPDG, que desenvolveu puberdade aos seis anos de idade. Sua mãe, com história de menarca aos dez anos de idade, era portadora da mesma variante em heterozigose. Células transfectadas estavelmente com GPR54 foram estimuladas com concentrações crescentes de kisspeptina-54 (kp-54) humana selvagem ou contendo as mutações (kp-54 H90D e kp-54 P74S) e o acúmulo de fosfato de inositol (IP) foi medido. Nos estudos in vitro, a kp-54 P74S apresentou uma capacidade de ativação do receptor GPR54 semelhante à kp-54 selvagem. A kp-54 p.H90D mostrou uma ativação da sinalização do receptor significativamente mais potente que a kp-54 selvagem, sugerindo que essa é uma mutação ativadora. No grupo de HHI, uma nova variante (c.588-589insT) foi identificada em heterozigose na região 3 não traduzida do gene KISS1 em um paciente do sexo masculino. O papel dessa variante no fenótipo de HHI permanece indeterminado. Em conclusão, duas mutações no gene KiSS1 foram descritas pela primeira vez em associação com PPDG. / Kisspeptin, encoded by the KISS1 gene, is an important regulator of puberty onset. After binding to its receptor GPR54, kisspeptin stimulates gonadotropin-releasing hormone secretion by the hypothalamic neurons. Inactivating GPR54 mutations are a rare cause of normosmic isolated hypogonadotropic hypogonadism (IHH). Recently, a unique GPR54 activating mutation was implicated in the pathogenesis of gonadotropin dependent precocious puberty (GDPP). Based on these observations, we hypothesized that mutations in the KISS1 gene might be associated with central pubertal disorders. The aim of this study was to investigate KISS1 mutations in idiopathic GDPP and normosmic IHH. Sixty-seven Brazilian children (63 girls and 4 boys) with idiopathic GDPP and 61 patients with normosmic IHH (40 men and 21 women) were selected. Familial and sporadic cases were included in both groups. The control population consisted of 200 individuals who had normal timing of puberty. The promoter region and the 3 exons of the KISS1 gene were amplified and automatically sequenced. Two novel KISS1 missense mutations, p.P74S and p.H90D, were identified in two unrelated children with idiopathic GDPP. Both mutations were absent in 400 control alleles and are located in the amino-terminal region of kisspeptin-54. The p.P74S mutation was identified in the heterozygous state in a boy who developed puberty at 1 yr of age. His mother and maternal grandmother, who had normal pubertal development, were also heterozygous for the p.P74S mutation, suggesting incomplete penetrance and/or sex-dependent inheritance. The p.H90D mutation was identified in the homozygous state in a girl with GDPP, who developed puberty at 6 yr of age. Her mother, who had menarche at 10 yr of age, carried the p.H90D mutation in the heterozygous state. CHO cells stably transfected with GPR54 were stimulated with different concentrations of synthetic human wild type or mutant kisspeptin-54 (KP54) and inositol phosphate (IP) accumulation was measured. In vitro studies revealed that the capacity of the p.P74S mutant KP54 to stimulate IP production was similar to the wild type. The p.H90D kisspeptin-54 showed a significantly more potent activation of GPR54 signaling in comparison to the wild type in vitro, suggesting a gain-of-function mutation. In the IHH group, a heterozygous variant in the 3 UTR of the KISS1 gene (c.588-589insT) was identified. The role of this variant in the IHH phenotype remains to be determined. In conclusion, two KiSS1 mutations were described for the first time in association with GDPP.
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Comparação entre dois protocolos para estimulação ovariana com agonista/antagonista do hormônio liberador de gonadotrofinas (GnRH) em mulheres submetidas ao primeiro ciclo de reprodução assistida / Comparison GnRH agonist short protocol and GnRH antagonist in Brazilian normoresponder patients undergoing their first cycle of controlled ovarian stimulationArruda, Jalsi Tacon 01 July 2013 (has links)
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Previous issue date: 2013-07-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Infertility affects more couples and assisted reproduction techniques offer a
possibility of treatment and the chance of having a child. Thus, the first attempt to
ovulation induction is critical to the success of the cycle or even for future attempts
is successful. Objective: To compare the protocols using GnRH agonist or
antagonist for ovarian stimulation in normo-responders undergoing the first cycle
of IVF/ICSI. Methods: we conducted a literature review on the history of ovulation
induction controlled by medications. From the data available in the database of
electronic medical records SISFERT used in the Laboratory of Human
Reproduction (LabRep-HC-FM-UFG) a comparative retrospective observational
study was conducted with 50 patients divided into two groups according to
protocol: GnRH-agonist (leuprolide acetate 1 mg/day short protocol) or GnRHantagonist
(Cetrorelix 0.25 mg/day), which received 150 IU/day of rFSH (follitropin
alpha) and 250 µg of rhCG (alpha-coriogonadotrofina) in both groups. Results:
Statistically significant differences were observed in the days of stimulation with
rFSH, total dose of gonadotropin, days of use of GnRH, GnRH dose and total
number of follicles (≥ 16 mm) on the day of the group rhCG GnRH agonist. There
was no significant difference in other parameters, however, the number of oocytes
retrieved was slightly higher in the GnRH agonist, but fertilization rate was higher
in the GnRH-antagonist. Pregnancy rates and clinical chemistry were similar in
both groups. Conclusions: although no significant differences in the results
analyzed, the use of flexible antagonist protocol facilitates the handling and
enables the patient using much lower doses of gonadotropins itself as the
antagonist, reducing the cost of treatment when compared to the protocol with
GnRH agonist. / A infertilidade afeta cada vez mais casais e as técnicas de reprodução assistida
oferecem uma possibilidade de tratamento e a chance de ter um filho. Assim, a
primeira tentativa de indução da ovulação é fundamental para o sucesso do ciclo
ou, até mesmo, para que tentativas futuras sejam bem sucedidas. Objetivo:
comparar os protocolos utilizando agonista ou antagonista do GnRH para
estimulação ovariana em pacientes normo-respondedoras submetidas ao primeiro
ciclo de FIV/ICSI. Métodos: foi realizada uma revisão da literatura sobre a história
da indução da ovulação controlada por medicamentos. A partir dos dados
disponíveis no banco de prontuários eletrônicos SISFERT utilizado pelo
Laboratório de Reprodução Humana (LabRep–HC–FM–UFG), um estudo
observacional retrospectivo comparativo foi conduzido com 50 pacientes
distribuídas em dois grupos de acordo com o protocolo: GnRH-agonista (acetato
de leuprolide 1 mg/dia protocolo curto) ou GnRH-antagonista (cetrorelix 0,25
mg/dia); e que receberam 150 UI/dia de rFSH (alfa-folitropina) e 250 µg de rhCG
(alfa-coriogonadotrofina) em ambos os grupos. Resultados: foram observadas
diferenças estatisticamente significativas nos dias de estimulação com rFSH, dose
total de gonadotrofina, dias de uso do GnRH, dose total de GnRH e o número de
folículos (≥ 16 mm) no dia do rhCG no grupo GnRH-agonista. Não houve
diferença significativa nos outros parâmetros, no entanto, o número de oócitos
recuperados foi ligeiramente maior no grupo GnRH-agonista, mas a taxa de
fertilização foi maior no grupo GnRH-antagonista. As taxas de gravidez química e
clínica foram similares nos dois grupos. Conclusões: embora não tenha havido
diferenças significativas nos resultados analisados, o uso do protocolo flexível
com antagonista facilita a manipulação pela paciente usuária e possibilita doses
menores tanto de gonadotrofinas quanto do próprio antagonista, reduzindo o
custo do tratamento quando comparado ao protocolo com agonista do GnRH
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