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1.
Sci Rep ; 11(1): 22732, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815477

RESUMO

Utilizing corifollitropin alfa in GnRH antagonist (GnRHant) protocol in conjunction with GnRH agonist trigger/freeze-all strategy (corifollitropin alfa/GnRHant protocol) was reported to have satisfactory outcomes in women with polycystic ovary syndrome (PCOS). Although lessening in gonadotropin injections, GnRHant were still needed. In addition to using corifollitropin alfa, GnRHant was replaced with an oral progestin as in progestin primed ovarian stimulation (PPOS) to further reduce the injection burden in this study. We try to investigate whether this regimen (corifollitropin alfa/PPOS protocol) could effectively reduce GnRHant injections and prevent premature LH surge in PCOS patients undergoing IVF/ICSI cycles. This is a retrospective cohort study recruiting 333 women with PCOS, with body weight between 50 and 70 kg, undergoing first IVF/ICSI cycle between August 2015 and July 2018. We used corifollitropin alfa/GnRHant protocol prior to Jan 2017 (n = 160), then changed to corifollitropin alfa/PPOS protocol (n = 173). All patients received corifollitropin alfa 100 µg on menstruation day 2/3 (S1). Additional rFSH was administered daily from S8. In corifollitropin alfa/GnRHant group, cetrorelix 0.25 mg/day was administered from S5 till the trigger day. In corifollitropin alfa/PPOS group, dydrogesterone 20 mg/day was given from S1 till the trigger day. GnRH agonist was used to trigger maturation of oocyte. All good quality day 5/6 embryos were frozen, and frozen-thawed embryo transfer (FET) was performed on subsequent cycle. A comparison of clinical outcomes was made between the two protocols. The primary endpoint was the incidence of premature LH surge and none of the patients occurred. Dydrogesterone successfully replace GnRHant to block LH surge while an average of 6.8 days of GnRHant injections were needed in the corifollitropin alfa/GnRHant group. No patients suffered from ovarian hyperstimulation syndrome (OHSS). The other clinical outcomes including additional duration/dose of daily gonadotropin administration, number of oocytes retrieved, and fertilization rate were similar between the two groups. The implantation rate, clinical pregnancy rate, and live birth rate in the first FET cycle were also similar between the two groups. In women with PCOS undergoing IVF/ICSI treatment, corifollitropin alfa/PPOS protocol could minimize the injections burden with comparable outcomes to corifollitropin alfa/GnRHant protocol.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante Humano/farmacologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Infertilidade Feminina/tratamento farmacológico , Hormônio Luteinizante/antagonistas & inibidores , Síndrome do Ovário Policístico/tratamento farmacológico , Progestinas/farmacologia , Adulto , Feminino , Hormônio Foliculoestimulante Humano/administração & dosagem , Humanos , Infertilidade Feminina/patologia , Indução da Ovulação , Síndrome do Ovário Policístico/fisiopatologia , Gravidez , Progestinas/administração & dosagem , Estudos Retrospectivos
3.
Reprod Sci ; 28(11): 3164-3170, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34076868

RESUMO

Use of GnRH antagonists in IVF stimulation protocols shortens controlled ovarian hyperstimulation (COH) and reduces the risk of ovarian hyperstimulation syndrome (OHSS). However, profound reduction in LH levels has been associated with use of GnRH antagonists. This study aims to determine if LH suppression during GnRH antagonist cycles results in poorer IVF outcomes. This was a prospective pilot longitudinal study where serum LH levels were measured on day 2/3 of the menstrual cycle before COH, 1/2 days following institution of GnRH antagonist and at the day of ovulation trigger. A threshold of LH <0.5 IU/L was used to define profound LH suppression. Data on IVF outcomes was collected. Logistic regression analysis was used to investigate risk factors associated with LH suppression following GnRH antagonist IVF treatment. Ninety-one eligible women were recruited. Women underwent a standard antagonist cycle with Puregon 200u and Ganirelix. No participant had LH <0.5 IU/L prior to GnRH antagonist treatment, and 27 participants (29.7%) had significant LH suppression at either time point. Predictors of profound LH suppression following GnRH antagonist treatment identified (P < 0.20) were age (OR = 0.80, P = 0.013), no previous ovulation induction (OR = 0.26, P = 0.033) and previous GnRH antagonist IVF cycle (OR = 4.32, P = 0.125). Numbers of oocytes, embryos and ongoing pregnancy rates at 12 weeks gestation in patients with and without LH suppression did not differ significantly. We found associations between clinical characteristics and risk of profound LH suppression in women undergoing GnRH antagonist IVF cycles, but no significant differences in IVF and pregnancy outcomes between women with and without significant LH suppression.


Assuntos
Fertilização in vitro/métodos , Antagonistas de Hormônios/farmacologia , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/sangue , Resultado da Gravidez/epidemiologia , Adulto , Feminino , Hormônio Foliculoestimulante Humano/farmacologia , Seguimentos , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Estudos Longitudinais , Projetos Piloto , Gravidez , Estudos Prospectivos , Proteínas Recombinantes/farmacologia , Resultado do Tratamento , Adulto Jovem
4.
Elife ; 92020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32644040

RESUMO

The gonadotropin-releasing hormone (GnRH) neurons exhibit pulse and surge modes of activity to control fertility. They also exhibit an unusual bipolar morphology comprised of a classical soma-proximal dendritic zone and an elongated secretory process that can operate as both a dendrite and an axon, termed a 'dendron'. We show using expansion microscopy that the highest density of synaptic inputs to a GnRH neuron exists at its distal dendron. In vivo, selective chemogenetic inhibition of the GnRH neuron distal dendron abolishes the luteinizing hormone (LH) surge and markedly dampens LH pulses. In contrast, inhibitory chemogenetic and optogenetic strategies targeting the GnRH neuron soma-proximal dendritic zone abolish the LH surge but have no effect upon LH pulsatility. These observations indicate that electrical activity at the soma-proximal dendrites of the GnRH neuron is only essential for the LH surge while the distal dendron represents an autonomous zone where synaptic integration drives pulsatile GnRH secretion.


Assuntos
Dendritos/fisiologia , Hormônio Liberador de Gonadotropina/biossíntese , Hormônio Luteinizante/antagonistas & inibidores , Animais , Dendritos/efeitos dos fármacos , Feminino , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia
5.
Domest Anim Endocrinol ; 72: 106429, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32320933

RESUMO

Cumulus cells have an important role to play in the final preparation of the oocyte before ovulation. During the final phase of follicular differentiation, FSH levels are low and LH maintains follicular growth; however, it is not known if at that time LH has an influence on cumulus cells inside the follicle. In humans, LH is often inhibited to avoid a premature ovulatory LH surge. This procedure provides a tool to investigate the role of LH in follicular development. In this study, we investigated the impact of suppressing LH using the GnRH antagonist cetrorelix during an ovarian coasting stimulation protocol on the transcriptome of bovine cumulus cells (CC). Oocytes were collected twice from 6 dairy cows. For the first collection, the cows received FSH twice daily for 3 d, followed by FSH withdrawal for 68 h as a control protocol. For the second collection, the same stimulation protocol was used, but the cows also received, starting on day 2 of FSH stimulation, a GnRH antagonist once a day until recovery of the cumulus-oocyte complexes (COC). Half of the COC were subjected to in vitro maturation, fertilization, and culture to assess blastocyst rates. The other half of the COC underwent microarray analysis (n = 3 cows, 2 treatments, 6 oocyte collections) and qRT-PCR (n = 6 cows: 3 microarray cows +3 other cows, 2 treatments, 12 oocyte collections). The differential expression of specific genes was confirmed by RT-qPCR: decrease of ATP6AP2, SC4MOL, and OSTC and increase of PTGDS in the LH-inhibited condition. The global transcriptomic analysis of cumulus cells demonstrated that the inhibition of LH secretion may decrease survival and growth of the follicle. Moreover, the results suggested that LH may be important to cumulus for the maintenance of cellular mechanisms such as global RNA expression, protein and nucleic acid metabolism, and energy production. These results support the hypothesis that LH support is important during the final part of follicle maturation through its influence on the cumulus cells.


Assuntos
Bovinos , Células do Cúmulo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/análogos & derivados , Fase Luteal/fisiologia , Hormônio Luteinizante/antagonistas & inibidores , Animais , Células Cultivadas , Células do Cúmulo/metabolismo , Feminino , Hormônio Foliculoestimulante/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Antagonistas de Hormônios/farmacologia , Indução da Ovulação , Superovulação
6.
Can J Urol ; 27(2): 10167-10173, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32333736

RESUMO

INTRODUCTION: In this article we advance a potential explanation for the incidence of cardiovascular (CV) and cardiometabolic risk in patients undergoing androgen deprivation therapy (ADT) for prostate cancer. Our conceptual model involves the differential impact of gonadotropin-releasing hormone (GnRH) agonists and antagonists on the follicle-stimulating hormone (FSH) system. MATERIALS AND METHODS: Authors searched online repositories and meeting abstract databases for relevant materials. RESULTS: Mounting evidence links FSH with development and progression of prostate cancer. What is also becoming clear is that the differential effects of GnRH agonists and antagonists on FSH may at least partially explain the differing effects these agents have on CV risk during ADT. While GnRH antagonists immediately suppress FSH, GnRH agonists provoke a transient surge in FSH that may contribute to the higher CV risk observed with these agents. Additionally, recent studies suggest that GnRH antagonists may significantly reduce CV risk compared to GnRH agonists, particularly in men with pre-existing CV disease. CONCLUSIONS: Patients with cardiovascular risk factors who require ADT may benefit from the better control of FSH provided by GnRH antagonists. ADT itself appears to heighten CV risk, and data suggest that FSH may at least partly drive this risk by promoting inflammation, atherosclerosis, insulin resistance, adipocyte rearrangement and plaque instability.


Assuntos
Fatores de Risco Cardiometabólico , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/etiologia , Hormônio Foliculoestimulante/fisiologia , Hormônio Liberador de Gonadotropina/fisiologia , Hormônio Luteinizante/fisiologia , Neoplasias da Próstata/complicações , Doenças Cardiovasculares/epidemiologia , Hormônio Foliculoestimulante/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Hormônio Luteinizante/antagonistas & inibidores , Masculino , Neoplasias da Próstata/tratamento farmacológico , Medição de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-32153508

RESUMO

Spexin (SPX) is a 14 amino acid peptide hormone that has pleiotropic functions across vertebrates, one of which is involvement in the brain-pituitary-gonad axis of fish. SPX(1) has been identified in each class of vertebrates, and a second SPX (named SPX2) has been found in some non-mammalian species. We have cloned two spexin paralogs, designated as Spx1a and Spx1b, from Nile tilapia (Oreochromis niloticus) that have varying tissue distribution patterns. Spx1b is a novel peptide only identified in cichlid fish, and is more closely related to Spx1 than Spx2 homologs as supported by phylogenetic, synteny, and functional analyses. Kisspeptin, Spx, and galanin (Gal) peptides and their corresponding kiss receptors and Gal receptors (Galrs), respectively, are evolutionarily related. Cloning of six tilapia Galrs (Galr1a, Galr1b, Galr2a, Galr2b, Galr type 1, and Galr type 2) and subsequent in vitro second-messenger reporter assays for Gαs, Gαq, and Gαi suggests that Gal and Spx activate Galr1a/Galr2a and Galr2b, respectively. A decrease in plasma follicle stimulating hormone and luteinizing hormone concentrations was observed with injections of Spx1a or Spx1b in vivo. Additionally, application of Spx1a and Spx1b to pituitary slices decreased the firing rate of LH cells, suggesting that the peptides can act directly at the level of the pituitary. These data collectively suggest an inhibitory mechanism of action against the secretion of gonadotropins for a traditional and a novel spexin paralog in cichlid species.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Hormônios Peptídicos/metabolismo , Receptores de Galanina/metabolismo , Tilápia/metabolismo , Sequência de Aminoácidos , Animais , Hormônio Foliculoestimulante/antagonistas & inibidores , Hormônio Luteinizante/antagonistas & inibidores , Especificidade de Órgãos , Filogenia , Receptores de Galanina/genética , Homologia de Sequência de Aminoácidos , Sintenia , Tilápia/genética , Tilápia/crescimento & desenvolvimento
8.
Horm Behav ; 118: 104590, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31593698

RESUMO

Alzheimer's disease and other forms of cognitive decline are significantly more prevalent in post-menopausal women. Decreased estrogen levels, due to menopause or ovariectomy, may contribute to memory impairments and neurodegeneration. Another result of decreased estrogen levels is elevated luteinizing hormone (LH). Elevated LH after menopause/ovariectomy has been shown to impair cognition in both human and animal studies. Lowering LH levels rescues spatial memory in ovariectomized (ovx) rodents, yet the mechanisms of these effects are still unclear. Estrogens appear to exert some of their effects on memory by increasing levels of brain-derived neurotrophic factor (BDNF) in the hippocampus. In these studies, we explored whether lowering LH may act by increasing BDNF. Ovx rats were treated with Antide, a gonadotropin releasing hormone receptor antagonist that lowers LH levels, or with estradiol. Both Antide and estradiol treatment enhanced spatial memory in ovx females. Both were found to be ineffective when a BDNF receptor antagonist was administered. Immunohistochemical analysis revealed that both Antide and estradiol increased BDNF expression in the hippocampus. Dendritic spine density on pyramidal cells in CA1 was unchanged by any treatment. These results provide evidence for a relationship between LH and BDNF in the hippocampus and demonstrate that estrogen-increasing and LH-lowering treatments may both require BDNF signaling in order to improve spatial memory.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Antagonistas de Hormônios/farmacologia , Hormônio Luteinizante/antagonistas & inibidores , Oligopeptídeos/farmacologia , Ovariectomia , Memória Espacial/efeitos dos fármacos , Animais , Cognição/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Hipocampo/efeitos dos fármacos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Ratos , Ratos Sprague-Dawley
9.
Chemosphere ; 245: 125597, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864041

RESUMO

Acephate is an organophosphate pesticide. It is widely used. However, whether it inhibits androgen synthesis and metabolism remains unclear. In the current study, we investigated the effect of acephate on the inhibition of androgen synthetic and metabolic pathways in rat immature Leydig cells after 3-h culture. Acephate inhibited basal androgen output in a dose-dependent manner with the inhibition starting at 0.5 µM. It significantly inhibited luteinizing hormone and 8-Br-cAMP stimulated androgen output at 50 µM. It significantly inhibited progesterone-mediated androgen output at 50 µM. Further study demonstrated that acephate down-regulated the expression of Hsd3b1 and its protein at ≥ 0.5 µM, Lhcgr at 5 µM and Star at 50 µM. Acephate directly blocked rat testicular HSD3B1 activity at 50 µM. Acephate did not affect other androgen synthetic and metabolic enzyme activities as well as ROS production, proliferation, and apoptosis of immature Leydig cells. In conclusion, acephate targets LHCGR, STAR, and HSD3B1, thus blocking androgen synthesis in rat immature Leydig cells and HSD3B1 is being the most sensitive target of acephate.


Assuntos
Androgênios/metabolismo , Células Intersticiais do Testículo/efeitos dos fármacos , Compostos Organotiofosforados/farmacologia , Fosforamidas/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/análogos & derivados , 8-Bromo Monofosfato de Adenosina Cíclica/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/metabolismo , Masculino , Complexos Multienzimáticos/antagonistas & inibidores , Progesterona/farmacologia , Progesterona Redutase/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Receptores do LH/antagonistas & inibidores , Esteroide Isomerases/antagonistas & inibidores , Testículo/efeitos dos fármacos , Testículo/metabolismo
10.
Elife ; 72018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30565563

RESUMO

Neurokinin B (NKB) signaling is critical for reproduction in all studied species. The existing consensus is that NKB induces GnRH release via kisspeptin (Kiss1) stimulation in the arcuate nucleus. However, the stimulatory action of NKB is dependent on circulating estrogen (E2) levels, without which, NKB inhibits luteinizing hormone (LH) release. Importantly, the evidence supporting the kisspeptin-dependent role of NKB, derives from models of persistent hypogonadal state [e.g. Kiss1r knock-out (KO) mice], with reduced E2 levels. Here, we demonstrate that in the presence of E2, NKB signaling induces LH release in a kisspeptin-independent manner through the activation of NK3R (NKB receptor) neurons in the posterodorsal medial amygdala (MePD). Importantly, we show that chemogenetic activation of MePD Kiss1 neurons induces LH release, however, the stimulatory action of NKB in this area is Kiss1 neuron-independent. These results document the existence of two independent neuronal circuitries within the MePD that regulate reproductive function in females. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).


Assuntos
Estrogênios/metabolismo , Kisspeptinas/genética , Neurocinina B/genética , Receptores de Taquicininas/genética , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Complexo Nuclear Corticomedial , Estrogênios/genética , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/genética , Hormônio Luteinizante/metabolismo , Camundongos , Camundongos Knockout , Neurocinina B/metabolismo , Neurônios/metabolismo , Transdução de Sinais
11.
Pak J Pharm Sci ; 31(4(Supplementary)): 1565-1570, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30058549

RESUMO

Prevalence of hepatitis C virus (HCV) has been seen in more than 15% of Pakistani population. For the treatment of this infection, only two medicines, interferon, and ribavirin were approved in 1998. The concerned physicians evaluate side effects of these two antiviral drugs only during the treatment period. The long-term extra hepatic side effects are being neglected. This retrospective study was conducted with reference to induced infertility in HCV treated 40 male patients from the period 2008-2015. Possible effects of interferon therapy on fertility hormones and seminal parameters were assessed. Level of fertility hormones like serum Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), and testosterone was measured. For seminal parameters, guidelines from World Health Organization (WHO) were followed. Among forty cases of HCV patients who received interferon, only 14 (35%) have children and 26 (65%) could not conceive (p = 0.0372). After HCV treatment, HCV positive patients showed a significant change in the level of FSH, LH (p<0.05). Especially, it decreased testosterone level (p=0.0096). Similarly, HCV treatment significantly decreased sperm count (p=0.001) and motility (p=0.0005).


Assuntos
Antivirais/efeitos adversos , Infertilidade Masculina/sangue , Infertilidade Masculina/induzido quimicamente , Interferons/efeitos adversos , Motilidade dos Espermatozoides/efeitos dos fármacos , Adulto , Hormônio Foliculoestimulante/antagonistas & inibidores , Hormônio Foliculoestimulante/sangue , Hepatite C/sangue , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Humanos , Infertilidade Masculina/diagnóstico , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Motilidade dos Espermatozoides/fisiologia , Testosterona/antagonistas & inibidores , Testosterona/sangue , Adulto Jovem
12.
Ceska Gynekol ; 83(1): 11-16, 2018.
Artigo em Tcheco | MEDLINE | ID: mdl-29510633

RESUMO

OBJECTIVE: To compare the results of ovarian stimulation with LH surge blockade by medroxyprogesterone acetate or GnRH antagonist in oocytes donors. To present current options of exogenous and endogenous progestins instead of GnRH analogues to block LH surge during ovarian stimulation. DESIGN: Retrospective study of oocyte donor cycles and literature review. SETTING: Department of Obstetrics and Gynecology, Faculty of Medicine, Masaryk university and University Hospital Brno. METHODS: Thirteen oocyte donors (26.8 ± 2.5 years old) were stimulated with recFSH and MPA to block the LH surge during January - October 2017. The results were compared to the previous cycle stimulated with recFSH and GnRH antagonist performed during January -December 2016. Wilcoxon´s pair test was used to test the statistics. A literature search of SCOPUS was carried out. RESULTS: In cycles with MPA blockade the average number of oocytes was 14.5 ± 5.1, in cycles with GnRH anta-gonist blockade 12.0 ± 4.5 oocytes (statistical significance p = 0.025). FSH total dose (1611 ± 327 vs. 1565 ± 322 IU), days of stimulation (9.1 ± 0.8 vs. 8.5 ± 0.9) and maximum estradiol levels (5.9 ± 2.1 vs. 6.0 ± 3.0 nmol/l) were not statistically different. Progestins are effective in blocking the LH surge during ovarian stimulation and do not affect the number and quality of collected oocytes or obtained embryos. Their adverse effect on the endometrial receptivity obstructs the embryo implantation in the same cycle. Such protocol requires total freezing and delayed transfer. Progestins can be used in a variety of stimulation protocols - progestin primed follicular phase stimulation, luteal phase stimulation with endogenous progesteron, double stimulation in follicular and luteal phase of the same cycle "duostim" in low responders. CONCLUSION: Eggs donor ovarian stimulation with MPA resulted in more oocytes than stimulation protocol with GnRH antagonist, the total dose of FSH and the length of stimulation were similar. According to current experiences progestins effectively block the LH surge and do not affect the number and quality of collected eggs and obtained embryos. Their use opens new possibilities of ovarian stimulation protocols and their flexibility. Its main constraint is that it requires total freezing and delayed transfer.


Assuntos
Anticoncepcionais Femininos/uso terapêutico , Hormônio Luteinizante/antagonistas & inibidores , Acetato de Medroxiprogesterona/uso terapêutico , Doação de Oócitos , Indução da Ovulação/métodos , Adulto , Feminino , Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/uso terapêutico , Humanos , Gravidez , Estudos Retrospectivos , Adulto Jovem
13.
Eur J Pharmacol ; 824: 24-29, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29378196

RESUMO

Gonadotropin releasing hormone (GnRH) analogs have long been used in androgen deprivation therapy (ADT) in the treatment of prostate cancer. Chronic administration of either GnRH agonists or antagonists leads to suppression of testosterone production in the testes via either downregulation or direct blockade of the GnRH receptor in the pituitary, respectively. Chronic administration of kisspeptin analogs has more recently been shown to lead to testosterone suppression via desensitization of GnRH neurons in the hypothalamus and an optimized kisspeptin analog, TAK-448, was proven effective in a small phase 1 trial. The current study explored the hypothesis that co-administration of TAK-448 and the GnRH antagonist, degarelix, would have an additive effect on hormonal suppression, as a result of simultaneous intervention in separate steps in the same pathway. TAK-448 or degarelix were first administered individually to castrated rats in order to identify low doses capable of partial or no suppression of luteinizing hormone (LH). In the second step, combinations of the low doses of TAK-448 and degarelix were assessed in a 14 day study and compared to the drugs administered separately. The results showed that simultaneous intervention at the kisspeptin and GnRH receptors caused a more pronounced LH suppression than either drug alone, demonstrating an additive or potentiating effect. These results suggest that such a drug combination may hold promise as novel forms of androgen deprivation therapy in the treatment of prostate cancer.


Assuntos
Castração , Kisspeptinas/administração & dosagem , Kisspeptinas/farmacologia , Hormônio Luteinizante/antagonistas & inibidores , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacologia , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Hormônio Luteinizante/sangue , Masculino , Ratos , Ratos Sprague-Dawley
14.
Eur J Med Chem ; 145: 413-424, 2018 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-29335207

RESUMO

We investigated a series of uracil analogues by introducing various substituents on the phenyl ring of the N-3 aminoethyl side chain and evaluated their antagonistic activity against human gonadotropin-releasing hormone (GnRH) receptors. Analogues with substituents at the ortho or meta position demonstrated potent in vitro antagonistic activity. Specifically, the introduction of a 2-OMe group enhanced nuclear factor of activated T-cells (NFAT) inhibition up to 6-fold compared to the unsubstituted analogue. We identified compound 12c as a highly potent GnRH antagonist with moderate CYP inhibition. Compound 12c showed potent and prolonged LH suppression after a single dose was orally administered in castrated monkeys compared to a known antagonist, Elagolix. We believe that our SAR study offers useful insights to design GnRH antagonists as a potential treatment option for endometriosis.


Assuntos
Inibidores do Citocromo P-450 CYP3A/farmacologia , Citocromo P-450 CYP3A/metabolismo , Receptores LHRH/antagonistas & inibidores , Uracila/farmacologia , Animais , Inibidores do Citocromo P-450 CYP3A/administração & dosagem , Inibidores do Citocromo P-450 CYP3A/química , Relação Dose-Resposta a Droga , Humanos , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/sangue , Macaca fascicularis , Estrutura Molecular , Relação Estrutura-Atividade , Uracila/análogos & derivados , Uracila/química
15.
J Nutr Biochem ; 47: 21-28, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28501702

RESUMO

Polycystic ovary syndrome (PCOS) is a complex endocrinopathy that is characterized by anovulation, hyperandrogenism and polycystic ovary. However, there is a lack of effective treatment for PCOS at present because the pathologic cause of PCOS has not been elucidated. Although it has been known that brown adipose tissue transplantation ameliorates PCOS by activating endogenous BAT, BAT transplantation is not applicable in clinic. Therefore, BAT activation with natural compound could be an effective treatment strategy for PCOS patients. Here, we found that 3 weeks of rutin (a novel compound for BAT activation) treatment increased BAT activation, thereby it improved thermogenesis and systemic insulin sensitivity in dehydroepiandrosterone (DHEA)-induced PCOS rat. In addition, the expression levels of ovarian steroidogenic enzymes such as P450C17, aromatase, 3ß-HSD, 17ß-HSD and STAR were up-regulated in rutin-treated PCOS rat. Furthermore, acyclicity and the serum level of luteinizing hormone were normalized, and a large number of mature ovulated follicle with a reduction of cystic formation were observed in PCOS rat after rutin treatment. Finally, rutin treatment surprisingly improved fertility and birth defect in PCOS rat. Collectively, our results indicate that rutin treatment significantly improves systemic insulin resistance and ovarian malfunction in PCOS, and our findings in this study provide a novel therapeutic option for the treatment of PCOS by activating BAT with rutin.


Assuntos
Tecido Adiposo Marrom/metabolismo , Modelos Animais de Doenças , Resistência à Insulina , Ovário/fisiopatologia , Síndrome do Ovário Policístico/dietoterapia , Rutina/uso terapêutico , Termogênese , Tecido Adiposo Marrom/patologia , Animais , Anovulação/etiologia , Anovulação/prevenção & controle , Anti-Inflamatórios não Esteroides/uso terapêutico , Fármacos Antiobesidade/uso terapêutico , Biomarcadores/sangue , Biomarcadores/metabolismo , Anormalidades Congênitas/etiologia , Anormalidades Congênitas/prevenção & controle , Desidroepiandrosterona , Indução Enzimática , Feminino , Infertilidade Feminina/etiologia , Infertilidade Feminina/prevenção & controle , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/sangue , Ovário/metabolismo , Ovário/patologia , Fosfoproteínas/agonistas , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Síndrome do Ovário Policístico/fisiopatologia , Ratos Sprague-Dawley , Termografia , Imagem Corporal Total
16.
eNeuro ; 4(1)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28144621

RESUMO

Kisspeptin (Kiss1) neurons in the hypothalamic arcuate nucleus (ARC) are key components of the hypothalamic-pituitary-gonadal axis, as they regulate the basal pulsatile release of gonadotropin releasing hormone (GnRH). ARC Kiss1 action is dependent on energy status, and unmasking metabolic factors responsible for modulating ARC Kiss1 neurons is of great importance. One possible factor is glucagon-like peptide 1 (GLP-1), an anorexigenic neuropeptide produced by brainstem preproglucagon neurons. Because GLP fiber projections and the GLP-1 receptor (GLP-1R) are abundant in the ARC, we hypothesized that GLP-1R signaling could modulate ARC Kiss1 action. Using ovariectomized mice, we found that GLP-producing fibers come in close apposition with ARC Kiss1 neurons; these neurons also contain Glp1r mRNA. Electrophysiological recordings revealed that liraglutide (a long-acting GLP-1R agonist) increased action potential firing and caused a direct membrane depolarization of ARC Kiss1 cells in brain slices. We determined that brainstem preproglucagon mRNA is decreased after a 48-h fast in mice, a negative energy state in which ARC Kiss1 expression and downstream GnRH/luteinizing hormone (LH) release are potently suppressed. However, activation of GLP-1R signaling in fasted mice with liraglutide was not sufficient to prevent LH inhibition. Furthermore, chronic central infusions of the GLP-1R antagonist, exendin(9-39), in ad libitum-fed mice did not alter ARC Kiss1 mRNA or plasma LH. As a whole, these data identify a novel interaction of the GLP-1 system with ARC Kiss1 neurons but indicate that CNS GLP-1R signaling alone is not critical for the maintenance of LH during fasting or normal feeding.


Assuntos
Núcleo Arqueado do Hipotálamo/metabolismo , Jejum/metabolismo , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Kisspeptinas/metabolismo , Hormônio Luteinizante/sangue , Neurônios/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/citologia , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Tronco Encefálico/citologia , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/metabolismo , Implantes de Medicamento , Ingestão de Alimentos/fisiologia , Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Feminino , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Receptor do Peptídeo Semelhante ao Glucagon 1/antagonistas & inibidores , Peptídeos Semelhantes ao Glucagon/metabolismo , Hormônio Luteinizante/antagonistas & inibidores , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos Endogâmicos C57BL , Neurônios/citologia , Neurônios/efeitos dos fármacos , Ovariectomia , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Técnicas de Cultura de Tecidos
17.
Domest Anim Endocrinol ; 58: 97-103, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27792889

RESUMO

This study tested the hypothesis that salsolinol, a derivative of dopamine, affects GnRH and LH secretion in lactating sheep. In the in vivo experiment, the structural analogue of salsolinol, 1-methyl-3,4-dihydroisoquinoline (1-MeDIQ), was infused into the infundibular nucleus-median eminence of sheep at the fifth wk of lactation to antagonize salsolinol's action. Simultaneously, cerebrospinal fluid from the third brain ventricle, to determine GnRH concentration, and plasma samples, to measure LH concentration, were collected. In the in vitro experiment, the anterior pituitary (AP) explants from weaned sheep were incubated in culture medium containing 2 doses of salsolinol, 20 and 100 µg/mL (S20 and S100, respectively). The concentration of LH in the collected media and relative expression of LHß subunit messenger RNA in the AP explants were determined. No significant difference was found in mean GnRH concentration in response to 1-MeDIQ infusion, but both mean plasma LH concentration and LH pulse frequency increased significantly (P < 0.001 and P < 0.05, respectively) compared with those in controls. Significantly higher LH concentrations occurred during the first (P < 0.001), second (P < 0.001), and fourth (P < 0.05) h of 1-MeDIQ infusion. In the in vitro study, both the S20 and S100 doses of salsolinol caused a significant decrease in the mean medium LH concentration compared with that in the control (P < 0.01 and P < 0.001, respectively). Salsolinol had no effect on the relative LHß subunit messenger RNA expression in the incubated tissue. In conclusion, salsolinol is a potential inhibitor of the secretory activity of the gonadotropic axis in lactating sheep, at least at the AP level. Although no significant changes in GnRH release were directly confirmed, an increase in the frequency of LH pulses does not allow to exclude the central action of salsolinol.


Assuntos
Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Isoquinolinas/administração & dosagem , Lactação/fisiologia , Hormônio Luteinizante/antagonistas & inibidores , Ovinos/fisiologia , Animais , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Meios de Cultivo Condicionados/análise , Feminino , Expressão Gênica , Hormônio Liberador de Gonadotropina/líquido cefalorraquidiano , Hormônio Liberador de Gonadotropina/metabolismo , Isoquinolinas/antagonistas & inibidores , Hormônio Luteinizante/análise , Hormônio Luteinizante/sangue , Hormônio Luteinizante Subunidade beta/genética , Eminência Mediana/efeitos dos fármacos , Doenças da Hipófise/metabolismo , RNA Mensageiro/análise , Técnicas de Cultura de Tecidos
18.
J Pediatr Endocrinol Metab ; 29(11): 1249-1257, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27740929

RESUMO

BACKGROUND: Peak gonadotropin-releasing hormone or agonist (GnRHa) stimulated luteinizing hormone (LH) testing with leuprolide acetate (LA) is commonly used to document suppression during therapy for central precocious puberty (CPP). The objective of the study was to investigate suitability of using basal LH levels to monitor GnRHa treatment and to determine optimal transition from 1-month to 3-month LA formulations via a post hoc analysis of a randomized, open-label, 6-month study. METHODS: A total of 42 children with CPP, pretreated with 7.5-, 11.25-, or 15-mg 1-month LA formulations were randomized to 11.25- or 30-mg 3-month LA. Basal LH/peak-stimulated LH levels were measured at weeks 0, 4, 8 and 12. Positive/negative predictive values and sensitivities/specificities were determined for basal LH vs. LH-stimulation results. RESULTS: Pretreatment with any 1-month formulation for the most part did not affect continuation of suppression after transitioning to 3-month formulation (mean peak-stimulated LH levels remained < 4 IU/L). Basal LH predicted suppression escape (basal LH-level cutoff ≥ 0.6 IU/L predicted 70% of those failing suppression). Tolerability was similar, regardless of dose. CONCLUSIONS: Our data indicate that a basal level of <0.60 IU/L is adequate for monitoring suppression approximately two-thirds of the time. Furthermore, the effectiveness and safety of 3-month LA treatments are not influenced by previous CPP therapies.


Assuntos
Monitoramento de Medicamentos , Hormônio Liberador de Gonadotropina/agonistas , Leuprolida/administração & dosagem , Hormônio Luteinizante/sangue , Puberdade Precoce/tratamento farmacológico , Substâncias para o Controle da Reprodução/administração & dosagem , Criança , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/efeitos adversos , Preparações de Ação Retardada/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Hormônio Foliculoestimulante Humano/antagonistas & inibidores , Hormônio Foliculoestimulante Humano/sangue , Hormônio Foliculoestimulante Humano/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Leuprolida/efeitos adversos , Leuprolida/uso terapêutico , Hormônio Luteinizante/antagonistas & inibidores , Hormônio Luteinizante/metabolismo , Masculino , Microesferas , Ovário/efeitos dos fármacos , Ovário/metabolismo , Puberdade Precoce/sangue , Substâncias para o Controle da Reprodução/efeitos adversos , Substâncias para o Controle da Reprodução/uso terapêutico , Estudos Retrospectivos , Testículo/efeitos dos fármacos , Testículo/metabolismo
19.
Proc Natl Acad Sci U S A ; 113(15): 4212-7, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27035990

RESUMO

The progesterone receptor (PGR) is a ligand-activated transcription factor with key roles in the regulation of female fertility. Much has been learned of the actions of PGR signaling through the use of pharmacologic inhibitors and genetic manipulation, using mouse mutagenesis. Characterization of rats with a null mutation at the Pgr locus has forced a reexamination of the role of progesterone in the regulation of the female reproductive cycle. We generated two Pgr mutant rat models, using genome editing. In both cases, deletions yielded a null mutation resulting from a nonsense frame-shift and the emergence of a stop codon. Similar to Pgr null mice, Pgr null rats were infertile because of deficits in sexual behavior, ovulation, and uterine endometrial differentiation. However, in contrast to the reported phenotype of female mice with disruptions in Pgr signaling, Pgr null female rats exhibit robust estrous cycles. Cyclic changes in vaginal cytology, uterine histology, serum hormone levels, and wheel running activity were evident in Pgr null female rats, similar to wild-type controls. Furthermore, exogenous progesterone treatment inhibited estrous cycles in wild-type female rats but not in Pgr-null female rats. As previously reported, pharmacologic antagonism supports a role for PGR signaling in the regulation of the ovulatory gonadotropin surge, a result at variance with experimentation using genetic ablation of PGR signaling. To conclude, our findings in the Pgr null rat challenge current assumptions and prompt a reevaluation of the hormonal control of reproductive cyclicity.


Assuntos
Progesterona/fisiologia , Reprodução/fisiologia , Animais , Éxons , Feminino , Hormônio Luteinizante/antagonistas & inibidores , Mifepristona/farmacologia , Mutação , Progesterona/genética , Ratos
20.
Int J Gynaecol Obstet ; 134(1): 8-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27067074

RESUMO

BACKGROUND: Although most low-dose combined oral contraceptives (COCs) include 7-day hormone-free intervals (HFIs), these COCs could incompletely suppress ovarian activity. OBJECTIVES: To review the impact of HFIs on ovarian suppression and tolerability, and evaluate the utility of COCs without traditional 7-day HFIs. SEARCH STRATEGY: PubMed was searched for clinical studies published in English between January 1980 and April 2015 on the impact of HFIs and HFI modifications in COCs. SELECTION CRITERIA: Articles assessing contraceptive efficacy or tolerability as the primary focus were included. DATA COLLECTION AND ANALYSIS: Abstracts of 319 articles were screened. RESULTS: Analysis of the 161 articles selected revealed that suppression of ovarian activity with low-dose COCs with 7-day HFIs is suboptimal. Loss of ovarian suppression during 7-day HFIs is commonly associated with follicular development, and most dominant follicles appear during this period. By contrast, increased ovarian suppression was noted in regimens that shortened or eliminated the HFI, or that substituted low-dose ethinyl estradiol for the HFI. CONCLUSIONS: Extended regimens with modified HFIs may provide greater ovarian suppression with the potential for increased contraceptive effectiveness. Additional research is needed to evaluate whether COC regimens that include 10µg ethinyl estradiol instead of an HFI may improve tolerability.


Assuntos
Anticoncepcionais Orais Combinados/administração & dosagem , Anticoncepcionais Orais Hormonais/administração & dosagem , Estrogênios/administração & dosagem , Etinilestradiol/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Anticoncepcionais Orais Combinados/efeitos adversos , Anticoncepcionais Orais Hormonais/efeitos adversos , Desogestrel/administração & dosagem , Estrogênios/efeitos adversos , Etinilestradiol/efeitos adversos , Feminino , Hormônio Foliculoestimulante/antagonistas & inibidores , Humanos , Hormônio Luteinizante/antagonistas & inibidores
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