RESUMO
Abstract Objective The aim of the present retrospective study was to investigate the effectiveness of single-dose gonadotropin releasing hormone (GnRH) antagonist administration, the day after human chorionic gonadotropin (hCG) triggering for final oocyte maturation, on the prevention of premature luteinization in patients with diminished ovarian reserve in in-vitro fertilization (IVF) cycles. The secondary objective of the study was to search the effect of this protocol on pregnancy outcomes. Methods This is a retrospective study including 267 infertile patients who have single antral follicle seen with ultrasonography on the 2nd or 3rd day of the menstrual cycle before starting IVF treatment. We randomized patients into two groups. The case group comprised patients who had single-dose GnRH antagonist injection the day after hCG triggering formed, and the patients who had the standard treatment regime formed the control group. In both groups, the oocytes were collected 36 hours after hCG injection. Results The premature ovulation rate was significantly low in the case group compared with the control group (6.86 versus 20.6% per scheduled cycle) (p=0.022). Also, the oocyte retrieval rate (93.14 versus 67.87% per scheduled cycle) (p=0.013), the oocyte maturity rate (79.42 versus 47.87%) (p=0.041), the fertilization rate (65.68 versus 34.54%) (p=0.018), and the embryo transfer rate per scheduled cycle (44.11 versus 18.78%) (p=0.003) were higher in the GnRH antagonist group than in the control group. Conclusion The administration of GnRH antagonist the day after hCG trigger in IVF treatments of patients with diminished ovarian reserve enabled a significant decrease in the rate of premature ovulation but had no effect on live birth rate.
Resumo Objetivo O objetivo do presente estudo retrospectivo foi investigar a eficácia da administração do antagonista do hormônio liberador da gonadotrofina (GnRH) em dose única no dia seguinte ao desencadeamento da gonadotrofina coriônica humana (hCG) para a maturação final do oócito, na prevenção da luteinização prematura em pacientes com diminuição do ovário reserva em ciclos de fertilização in vitro (FIV). O objetivo secundário do estudo foi pesquisar o efeito deste protocolo nos resultados da gravidez. Métodos Trata-se de um estudo retrospectivo incluindo 267 pacientes inférteis que apresentam um único folículo antral visto por ultrassonografia no 2° ou 3° dia do ciclo menstrual antes de iniciar o tratamento de FIV. Nós randomizamos os pacientes em dois grupos. Os pacientes que receberam injeção de antagonista de GnRH em dose única no dia seguinte ao desencadeamento do hCG formaram o grupo caso, e os pacientes que receberam o regime de tratamento padrão formaram o grupo controle. Em ambos os grupos, os oócitos foram coletados 36 horas após a injeção de hCG. Resultados A taxa de ovulação prematura foi significativamente baixa no grupo caso em comparação com o grupo controle (6,86 versus 20,6% por ciclo programado) (p=0,022). Além disso, a taxa de recuperação de oócitos (93,14 versus 67,87% por ciclo programado) (p=0,013), a taxa de maturidade do oócito (79,42 versus 47,87%) (p=0,041), a taxa de fertilização (65,68 versus 34,54%) (p=0,018) e a taxa de transferência de embriões por ciclo programado (44,11 versus 18,78%) (p=0,003) foram maiores no grupo antagonista de GnRH do que no grupo controle. Conclusão A administração de antagonista de GnRH, no dia seguinte ao desencadeamento de hCG em tratamentos de FIV de pacientes com reserva ovariana diminuída permitiu uma redução significativa na taxa de ovulação precoce,mas não teve efeito na taxa de nascidos vivos.
Assuntos
Humanos , Feminino , Gravidez , Oócitos , Receptores LHRH , Taxa de GravidezRESUMO
O procedimento de imunocastração vem sendo utilizado como técnica alternativa amplamente favorável ao bem-estar animal, por ser indolor, pouco invasiva e com eficácia semelhante à da castração cirúrgica, que causa maior estresse aos animais, principalmente quando realizada de forma inadequada. A imunocastração estimula a produção de anticorpos contra o Hormônio Liberador de Gonadotrofina (GnRH), bloqueando temporariamente a produção da testosterona pelas gônadas masculinas. Face a escassez de informações sobre este procedimento em touros bubalinos, o estudo teve como objetivo analisar os possíveis efeitos da imunocastração no parênquima testicular de búfalos. Vinte touros bubalinos, com idade entre 2 a 3 anos, oriundos da ilha do Marajó PA, foram avaliados e divididos aleatoriamente em dois grupos composto por dez animais no grupo controle (GC) e dez do grupo imunocastrado (GIM). O produto utilizado foi a vacina anti-GnRH Bopriva ® (Zoetis, SP, Brasil). O GIM recebeu duas doses de 1,0ml contendo 400µg da vacina Bopriva ® com intervalo de 8 semanas entre as aplicações e o grupo controle recebeu 1,0 ml de solução fisiológica. Após 14 dias da última dose, os animais foram abatidos e coletado os 20 pares de testículos para analises de parâmetros macroscópicos como: comprimento, largura, circunferência e peso. Além disso, foi realizada a retirada de fragmentos do parênquima testicular para confecção de lâminas histológicas. Para comparação dos dados foi aplicado o teste t de Student (Nonparametric Test) considerando a significância com p<0,05 e intervalo de confiança de 95%. Foi observado diferença significativa entre os dois grupos para grupos para peso (direto p<0001; esquerdo p≤ 0,0001), circunferência (direita p< <0,0001), 1; esquerda p<0,0001), ), largura (somente lado direito p<0,0372) e comprimento (direita p≤ 0,0013; esquerda p<0,0437). Na avaliação microscópica, os animais do GC não apresenteram alterações. Nos animais do GIM houve degeneração em todas as amostras, sendo visualizado descamação, tortuosidade e espessamento da membrana basal do túbulo seminífero, assim como vacuolização e atrofia das células de Sertoli. Foi observado também uma redução do número de células de Leydig, fibrose intertubular pronunciada, núcleos picnóticos, azoospermia e células multinucleadas no interior dos túbulos. Conclui-se a vacina anti-GnRH mostrou-se eficaz em provocar lesões no parênquima testicular, comprometendo significativamente a espermatogênese a partir da possível supressão de testosterona.(AU)
The immunocastration procedure has been used as an alternative technique widely favorable to animal welfare, as it is painless, minimally invasive and with similar efficacy to surgical castration, which causes greater stress to animals, especially when performed improperly. Immunocastration stimulates the production of antibodies against Gonadotropin Releasing Hormone (GnRH), temporarily blocking the production of testosterone by the male gonads. Due to the scarcity of information about this procedure in buffalo bulls, the study aimed to analyze the possible effects of immunocastration on the testicular parenchyma of buffaloes. Twenty buffalo bulls, aged between 2 and 3 years, from the island of Marajó - PA, were evaluated and randomly divided into two groups consisting of ten animals in the control group (CG) and ten from the immunocastrated group (GIM). The product used was the anti-GnRH vaccine Bopriva ® (Zoetis, SP, Brazil). The GIM received two doses of 1.0ml containing 400µg of Bopriva ® vaccine with an interval of 8 weeks between applications and the control group received 1.0 ml of saline solution. After 14 days of the last dose, the animals were slaughtered and the 20 pairs of testes were collected for analysis of macroscopic parameters such as: length, width, circumference and weight. In addition, fragments of the testicular parenchyma were removed for the preparation of histological slides. To compare the data, Student's t test (Nonparametric Test) was applied, considering the significance with p< 0.0372) and length (right p≤ 0.0013; left p<0.0437). In the microscopic evaluation, the animals of the CG showed no alterations. In the GIM animals there was degeneration in all samples, with desquamation, tortuosity and thickening of the seminiferous tubule basement membrane, as well as vacuolization and atrophy of Sertoli cells. A reduction in the number of Leydig cells, pronounced intertubular fibrosis, pyknotic nuclei, azoospermia and multinucleated cells within the tubules were also observed. In conclusion, the anti-GnRH vaccine proved to be effective in causing lesions in the testicular parenchyma, significantly compromising spermatogenesis from the possible suppression of testosterone.(AU)
Assuntos
Animais , Masculino , Búfalos/fisiologia , Castração/veterinária , Receptores LHRH/imunologia , Epitélio Seminífero/imunologia , Bem-Estar do AnimalRESUMO
BACKGROUND: GnRH analogs are widely used as neoadjuvant agents for radiotherapy in prostate cancer (PCa) patients, with well-documented effects in reducing tumor bulk and increasing progression-free survival. GnRH analogs act locally in the prostate by triggering apoptosis of PCa cells via activation of the GnRH receptor (GnRHR). During PCa progression, the distribution of GnRHR within the cell is altered, with reduced expression in the cell membrane and remaining sequestered in the endoplasmic reticulum. Pharmacoperone IN3 is able to relocalize GnRHR to the cell membrane. The aim of this study was to evaluate the effect of radiation on PCa cells pretreated with leuprolide, alone or in combination with IN3, as radiosensitizers. MATERIAL AND METHODS: PC3 and human PCa primary cell cultures were treated with IN3 for 24 h, followed by different doses of leuprolide for 48 h and, finally, single doses of radiation (3, 6, and 9 Gy). After radiation, cell survival, apoptosis, cell cycle distribution, and colony growth were evaluated. RESULTS: Radiation reduced cell survival and increased apoptosis in a dose-dependent manner. This effect was also directly related to leuprolide concentration. Pretreatment with IN3 enhanced apoptosis and decreased cell survival, also observing a higher proportion of cells arrested in G2. CONCLUSION: Neoadjuvant leuprolide increases radiation-mediated apoptosis of PCa cells. This effect was enhanced by pretreatment with pharmacoperone IN3. Clinical use of IN3 as a radiosensitizer combined with androgen deprivation therapy to improve survival of patients with PCa remains to be evaluated.
Assuntos
Neoplasias da Próstata , Antagonistas de Androgênios , Hormônio Liberador de Gonadotropina , Humanos , Leuprolida/farmacologia , Masculino , Próstata , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Radiossensibilizantes/farmacologia , Receptores LHRHRESUMO
The expression of the gonadotrophin-releasing hormone receptor expression on pituitary gonadotrophs in humans is well characterized. In nervous system they have also been found in hippocampi and cerebral cortex. However, gonadotrophin-releasing hormone receptor expression in human spinal cord has not been reported. This study was to analyze the gonadotrophin-releasing hormone receptor expression in human spinal cord by immunohistochemistry, mRNAs by reverse transcriptase polymerase chain reaction, cDNA cloning and Western blot. The results show immunoreactive material to gonadotrophin-releasing hormone receptor in motoneurons of the spinal cord. Further, the study revealed that spinal cord expressed the gonadotrophin-releasing hormone receptor mRNA. The amplicon sequence corresponds to 100% of identity to GenBank. In Western blot, a band of 37 kDa were found in extracts of spinal cord and placenta as a control. In conclusion, human spinal cord expresses gonadotrophin-releasing hormone receptor analyzed through immunohistochemistry, the expression of its mRNA, cloning its cDNA and Western blot analysis. The presence of gonadotrophin-releasing hormone receptor in the spinal cord suggests the possibility of an extrapituitary functional role independent of reproductive system.
Assuntos
Receptores LHRH/metabolismo , Medula Espinal/metabolismo , Adulto , Sequência de Bases , Feminino , Humanos , Imuno-Histoquímica , Masculino , Neurônios Motores/metabolismo , Placenta/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Receptores LHRH/genética , Medula Espinal/citologiaRESUMO
A dose-response study was made of the broad-spectrum gonadal steroid agonist tibolone (TBL) on lordosis behavior in estradiol benzoate (EB: 5 µg) primed rats. Doses of TBL (0, 1, 4, and 16 µg) were infused to the right lateral ventricle 2 h before testing. The highest dose increased lordosis quotients significantly at 240 min and 360 min following infusion. However, the intensity of lordosis was weak. In experiment 2, the TBL dose of 16 µg was selected to determine whether tamoxifen (TMX), RU486, or antide could modify the lordosis response to TBL. Infusions of the three compounds, before TBL, significantly attenuated the TBL-induced facilitation of lordosis. The results suggest that TBL stimulates lordosis by activating estrogen, progesterone, and may do so by downstream stimulation of GnRH release. The physiological role TBL plays in controlling lordosis behavior remains to be determined.
Assuntos
Moduladores de Receptor Estrogênico/farmacologia , Norpregnenos/farmacologia , Postura , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Antagonistas de Hormônios/farmacologia , Mifepristona/farmacologia , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/antagonistas & inibidores , Receptores LHRH/antagonistas & inibidores , Receptores de Progesterona/antagonistas & inibidoresRESUMO
In addition to key mammotrophic hormones such as the pituitary prolactin (PRL) and the ovarian steroids progesterone and estradiol, there are local factors that modulate the tissue dynamics of the mammary glands during pregnancy and lactation. By immunohistochemistry and RT-PCR, we found local transcription and translation of gonadotropin-releasing hormone (GNRH), GNRH receptor (GNRHR), PRL and PRL receptor (PRLR) in mammary glands of adult vizcachas during pregnancy and lactation. Both GNRH and GNRHR showed a lag between protein expression and gene transcription throughout the gestational period: while the highest transcription levels of these genes were recorded at early-pregnancy, the epithelial immunoexpressions of both showed their maximum during lactation. RIA results corroborated the presence of GNRH in mammary glands at all the analyzed stages and confirmed the maximum amount of this peptide in the lactating group. Significant amounts of GNRH were detected in milk samples as well. Conversely, PRL and PRLR shared similar protein and gene expression profiles, all exhibiting maximum values during lactation. GNRH peptide content in mammary glands of females with sulpiride-induced hyperprolactinemia (HP) was significantly lower than that of control females (CT). Although PRL mRNA levels remained unchanged, there was a marked increase in theα-lactalbumin (LALBA) transcription in mammary glands of HP- vs CT-females. These results suggest that after targeting mammary glands, PRL stimulates the expression of milk protein genes, but also, tempers the local expression of GNRH. Mammary gland-explantssupplemented with a GNRH analogue (GN-explants) had no differences in terms of PRLR orLALBA transcription levels compared to CT-explants, so the mammary PRLR signaling would not appear to be modulated by GNRH. Yet, mRNA expression levels of both GNRH and the GNRHR-downstream factor, EGR1, were significantly higher in GN-explants compared to that of CT which would point to a GNRH-positive feedback mechanism. In summary, the local coupled expression of GNRH, GNRHR and EGR1 in the mammary gland throughout pregnancy of vizcachas, the PRL-dependent mammary GNRH secretion as well as the GNRH positive feedback on its own transcription suggest an autocrine-paracrine regulatory mechanism and propose an active role for GNRH in mammary gland tissue remodeling.
Assuntos
Regulação da Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Homeostase , Glândulas Mamárias Animais/metabolismo , Receptores LHRH/genética , Roedores/genética , Animais , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Epitélio/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/metabolismo , Lactação/fisiologia , Ligantes , Especificidade de Órgãos , Gravidez , Prolactina/genética , Prolactina/metabolismo , RNA Mensageiro/metabolismo , Receptores LHRH/metabolismo , Receptores da Prolactina/genética , Receptores da Prolactina/metabolismo , Reprodução , Transdução de Sinais/efeitos dos fármacosRESUMO
Kisspeptin has been identified as a key regulatory protein in the release of gonadotropin-releasing hormone (GnRH), which subsequently increases gonadotropin secretion during puberty to establish reproductive function and regulate the hypothalamic-pituitary-gonadal axis. The effects of variants in the KISS1, KISS1R, and GNRHR genes and their possible association with assisted reproduction outcomes remain to be elucidated. In this study, we used next-generation sequencing to investigate the associations of the genetic diversity at the candidate loci for KISS1, KISS1R, and GNRHR with the hormonal profiles and reproductive outcomes in 86 women who underwent in vitro fertilization treatments. Variants in the KISS1 and KISS1R genes were associated with luteinizing hormone (rs35431622:T>C), anti-Mullerian hormone (rs71745629delT), follicle-stimulating hormone (rs73507529:C>A), and estradiol (rs73507527:G>A, rs350130:A>G, and rs73507529:C>A) levels, as well as with reproductive outcomes such as the number of oocytes retrieved (s35431622:T>C), metaphasis II oocytes (rs35431622:T>C), and embryos (rs1132506:G>C). Additionally, variants in the GNRHR UTR3' (rs1038426:C>A, rs12508464:A>C, rs13150734:C>A, rs17635850:A>G, rs35683646:G>A, rs35610027:C>G, rs35845954:T>C, rs17635749:C>T, and rs7666201:C>T) were associated with low prolactin levels. A conjoint analysis of clinical, hormonal, and genetic variables using a generalized linear model identified two variants of the KISS1 gene (rs71745629delT and rs1132506:G>C) that were significantly associated with hormonal variations and reproductive outcomes. The findings suggest that variants in KISS1, KISS1R, and GNRHR genes can modulate hormone levels and reproductive outcomes.
Assuntos
Variação Genética , Hormônio Liberador de Gonadotropina/metabolismo , Kisspeptinas/genética , Receptores de Kisspeptina-1/genética , Receptores LHRH/genética , Reprodução/genética , Adulto , Feminino , Loci Gênicos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Infertilidade/genéticaRESUMO
Prostate cancer (PCa) is the leading cause of male cancerassociated mortality worldwide. Mortality is associated with metastasis and hormone resistance. Cellular, genetic and molecular mechanisms underlying metastatic progression and hormone resistance are poorly understood. Studies have investigated the local effects of gonadotropinreleasing hormone (GnRH) analogs (used for androgen deprivation treatments) and the presence of the GnRH receptor (GnRHR) on PCa cells. Furthermore, cell subpopulations with stemlike properties, or cancer stem cells, have been isolated and characterized using a cell culture system derived from explants of human prostate tumors. In addition, the development of preclinical orthotopic models of human PCa in a nonobese diabetic/severe combined immunodeficiency mouse model of compromised immunity has enabled the establishment of a reproducible system of metastatic progression in vivo. There is increasing evidence that metastasis is a complex process involving the cooperative actions of different cancer cell subpopulations, in which cancer stemlike cells would be responsible for the final step of colonizing premetastatic niches. It has been hypothesized that PCa cells with stemness and mesenchymal signatures act cooperatively in metastatic progression and the inhibition of stemness genes, and that overexpression of androgen receptor (AR) and GnRHR decreases the rate the metastasis and sensitizes tumors to hormone therapy. The aim of the present review is to analyze the evidence regarding this cooperative process and the possible influence of stemlike cell phenotypes, AR and GnRHR in metastatic progression and hormone resistance. These aspects may represent an important contribution in the understanding of the mechanisms underlying metastasis and hormone resistance in PCa, and potential routes to blocking these processes, enabling the development of novel therapies that would be particularly relevant for patients with metastatic and castrationresistant PCa.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias da Próstata/genética , Receptores Androgênicos/genética , Receptores LHRH/genética , Antagonistas de Androgênios/uso terapêutico , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Receptores LHRH/metabolismoRESUMO
During the ovarian ontogeny in birds, five fundamental events can be recognized: migration and colonization of the primordial germ cells, differentiation and proliferation of oogonies, an organization of germinal nests, beginning of the meiotic process and folliculogenesis. The knowledge of these events is fundamental for the interpretation of the processes involved in the differentiation of female gametes. However, there are only references for some model species such as Gallus gallus domesticus and Coturnix coturnix. In a previous study, the histological structure of embryonic ovaries of Columba livia was revealed. Therefore, the objective of this work is to characterize the processes of meiosis and folliculogenesis C. livia from the analysis of the expression of the GnRH receptor, the 3ßHSD enzyme and the cell proliferation protein PCNA in embryonic and postnatal ovaries. Therefore, the expression of GnRHR, 3ßHSD, and PCNA was revealed in histological testicular and ovarian preparations in embryos (stages 41-43) and neonates (2, 5, 7, 10 and 75â¯days post-hatching). The present study demonstrates that the fate of germline cells is dictated by their location during gonadal development. Thus, the germline cells located in the cortex of the left gonad enter meiosis, while those in the right gonad and those in the medulla of the left ovary fail to go into meiosis. This indicates that somatic signals, instead of an autonomous cellular mechanism, regulate the entry of the germline cells into meiosis in the C. livia embryo. Future studies will be focused on the analysis of proteins associated with meiotic events and folliculogenesis in embryonic and neonatal ovaries of C. livia, to evaluate the regulation of meiosis in vitro.
Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Columbidae/metabolismo , Meiose , Folículo Ovariano/crescimento & desenvolvimento , Receptores LHRH/metabolismo , Animais , Proliferação de Células , Columbidae/embriologia , Embrião não Mamífero/citologia , Feminino , Células Germinativas/metabolismo , Imuno-Histoquímica , Oócitos/citologia , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismoRESUMO
CONTEXT: GH and IGF-1 are crucial for attainment of normal body size and regulation of food intake, nutrient storage, and insulin sensitivity. Enteroendocrine connections exist between the GH-IGF-1 axis and insulin, ghrelin, and glucagon-like peptide 1 (GLP-1). The status of these connections in GH deficiency (GHD) is unknown. OBJECTIVE: To study the enteroendocrine connections before and after a standard meal test in a homogeneous population of adults with congenital untreated isolated GHD (IGHD) due to a mutation in the GHRH receptor gene. DESIGN: In a cross-sectional study of 20 individuals with IGHD and 20 control subjects, we measured glucose, insulin, ghrelin, and GLP-1 before and 30, 60, 120, and 180 minutes after a standardized test meal. Homeostasis model assessment index of insulin resistance (HOMA-IR) and homeostasis model assessment (HOMA)-ß were calculated. Participants scored feelings of hunger, fullness, and prospective food consumption on a visual analog scale. MAIN OUTCOME MEASURES: Area under the curve (AUC) values of glucose, insulin, ghrelin, GLP-1, hunger, fullness, and prospective food consumption. RESULTS: Fasting HOMA-IR and HOMA-ß were lower in individuals with IGHD than in control subjects (P = 0.002 and P = 0.023, respectively). AUC was higher for hunger (P < 0.0001), glucose (P = 0.0157), ghrelin (P < 0.0001), and GLP-1 (P < 0.0001) and smaller for fullness (P < 0.0001) in individuals with IGHD compared with control subjects. There was no difference in AUC for prospective food consumption or insulin. CONCLUSIONS: Untreated IGHD is associated with increased GLP-1 secretion and reduced postprandial ghrelin and hunger attenuation in response to a mixed meal. These enteroendocrine connections can result in a favorable outcome in terms of environmental adaptation and guaranteeing appropriate food intake and can confer metabolic benefits.