Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
PLoS Comput Biol ; 20(1): e1011415, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38206994

RESUMO

Glycoprotein hormone receptors [thyrotropin (TSHR), luteinizing hormone/chorionic gonadotropin (LHCGR), and follicle stimulating hormone (FSHR) receptors] are rhodopsin-like G protein-coupled receptors. These receptors display common structural features including a prominent extracellular domain with leucine-rich repeats (LRR) stabilized by ß-sheets and a long and flexible loop known as the hinge region (HR), and a transmembrane (TM) domain with seven α-helices interconnected by intra- and extracellular loops. Binding of the ligand to the LRR resembles a hand coupling transversally to the α- and ß-subunits of the hormone, with the thumb being the HR. The structure of the FSH-FSHR complex suggests an activation mechanism in which Y335 at the HR binds into a pocket between the α- and ß-chains of the hormone, leading to an adjustment of the extracellular loops. In this study, we performed molecular dynamics (MD) simulations to identify the conformational changes of the FSHR and LHCGR. We set up a FSHR structure as predicted by AlphaFold (AF-P23945); for the LHCGR structure we took the cryo-electron microscopy structure for the active state (PDB:7FII) as initial coordinates. Specifically, the flexibility of the HR domain and the correlated motions of the LRR and TM domain were analyzed. From the conformational changes of the LRR, TM domain, and HR we explored the conformational landscape by means of MD trajectories in all-atom approximation, including a membrane of polyunsaturated phospholipids. The distances and procedures here defined may be useful to propose reaction coordinates to describe diverse processes, such as the active-to-inactive transition, and to identify intermediaries suited for allosteric regulation and biased binding to cellular transducers in a selective activation strategy.


Assuntos
Hormônio Foliculoestimulante , Simulação de Dinâmica Molecular , Sequência de Aminoácidos , Microscopia Crioeletrônica , Receptores do FSH/química , Receptores do FSH/metabolismo , Lipídeos
2.
JBRA Assist Reprod ; 27(1): 78-84, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36995260

RESUMO

OBJECTIVE: Follicle-stimulating hormone (FSH) is essential for folliculogenesis, acting through the follicle-stimulating hormone receptor (FSHR) that is present on the membrane of granulosa cells. Polymorphisms in the FSHR gene may lead to an altered pattern of receptor expression on the cell surface or to changes in affinity for FSH. The aim of this prospective study was to detect any association between the follicle-stimulating hormone receptor (FSHR) gene Ala307Thr polymorphism (rs6165) and ovarian reserve, ovarian response or clinical results in IVF/ICSI treatment. METHODS: This prospective cohort study included 450 women who underwent IVF/ICSI cycles. DNA was extracted from peripheral blood, and the Ala307Thr FSHR polymorphism (rs6165) was genotyped using the TaqMan SNP genotyping assay. Participants were divided into three groups according to their Ala307Thr FSHR genotype: Thr/Thr (n:141), Thr/Ala (n=213) and Ala/Ala (n=96). The results were tested for associations with age, anti-Mullerian hormone (AMH) levels, antral follicle count (AFC), total dose of r-FSH, follicle size, number of retrieved oocytes, and clinical outcome of IVF/ICSI cycles. The statistical analyses were performed using Fisher's exact test and the Kruskal‒Wallis test. RESULTS: An association between the genotype of the FSHR (Ala307Thr) polymorphism and the dose of r-FSH was observed. Patients with the Ala/Ala genotype received a higher r-FSH dose than patients with the Ala/Thr (p=0.0002) and Thr/Thr (p=0.02) genotypes. No other correlation was observed. CONCLUSION: The Ala/Ala genotype was associated with the use of higher doses of recombinant FSH (r-FSH), suggesting that homozygosis of this allelic variant (Ala) provides lower sensitivity to r-FSH.


Assuntos
Receptores do FSH , Injeções de Esperma Intracitoplásmicas , Feminino , Animais , Receptores do FSH/genética , Receptores do FSH/metabolismo , Estudos Prospectivos , Indução da Ovulação/métodos , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Foliculoestimulante Humano/uso terapêutico , Fertilização in vitro/métodos
3.
J Ovarian Res ; 14(1): 173, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-34895279

RESUMO

INTRODUCTION: The hypothalamic-pituitary-ovarian (HPO) axis is the principal regulator of the reproductive system. The neurons in the arcuate nucleus of the hypothalamus signal the basophilic cells of the anterior pituitary to release luteinizing hormone (LH) and follicle stimulating hormone (FSH), which bind to the granulosa and theca cells of a follicle in the ovary to promote healthy follicular development. Disruption of this process at any time can lead to polycystic ovaries and, if left untreated, can lead to Polycystic Ovarian Syndrome (PCOS), one of the leading causes of infertility. A novel treatment option using 150 kHz Intermediate Frequency (IF) Electromagnetic Radiation (EMR) has been proposed to monitor the effect of this frequency during cystic development. METHODS: To prove this, an experiment was conducted to study the effect of whole-body exposure to 150 kHz EMR for 8 weeks at receptor, cellular, tissue and hormonal levels on the HPO axis of 25 young cyclic female rats. RESULTS: The results showed that 150 kHz EMR did not affect the histoarchitecture of neurons of arcuate nucleus of the hypothalamus of PCO-induced rats. It was also found that the number of basophilic cells of the pituitary gland was increased and the immunoreactivity of LH and FSH secretion increased. This EMR field also decreased the development of follicular cysts in the ovary and possibly increased the immunoreactivity of the LH and FSH receptors as well on the theca and granulosa cells of follicles in the ovary. CONCLUSION: There are still many limitations to this study. If properly evaluated, the results of this experiment could help develop a new non-invasive treatment option for women with PCOS in the near future.


Assuntos
Magnetoterapia , Síndrome do Ovário Policístico/terapia , Animais , Modelos Animais de Doenças , Radiação Eletromagnética , Estradiol , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Hipotálamo/metabolismo , Hipotálamo/patologia , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Neurônios/citologia , Ovário/metabolismo , Ovário/patologia , Hipófise/metabolismo , Hipófise/patologia , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Ratos Sprague-Dawley , Receptores do FSH/metabolismo , Receptores do LH/metabolismo
4.
Int J Mol Sci ; 22(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34576272

RESUMO

Follicle stimulating hormone (FSH) is produced by the pituitary gland in a coordinated hypothalamic-pituitary-gonadal (HPG) axis event, plays important roles in reproduction and germ cell development during different phases of reproductive development (fetal, neonatal, puberty, and adult life), and is consequently essential for fertility. FSH is a heterodimeric glycoprotein hormone of two dissociable subunits, α and ß. The FSH ß-subunit (FSHß) function starts upon coupling to its specific receptor: follicle-stimulating hormone receptor (FSHR). FSHRs are localized mainly on the surface of target cells on the testis and ovary (granulosa and Sertoli cells) and have recently been found in testicular stem cells and extra-gonadal tissue. Several reproduction disorders are associated with absent or low FSH secretion, with mutation of the FSH ß-subunit or the FSH receptor, and/or its signaling pathways. However, the influence of FSH on germ cells is still poorly understood; some studies have suggested that this hormone also plays a determinant role in the self-renewal of germinative cells and acts to increase undifferentiated spermatogonia proliferation. In addition, in vitro, together with other factors, it assists the process of differentiation of primordial germ cells (PGCLCs) into gametes (oocyte-like and SSCLCs). In this review, we describe relevant research on the influence of FSH on spermatogenesis and folliculogenesis, mainly in the germ cell of humans and other species. The possible roles of FSH in germ cell generation in vitro are also presented.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Células da Granulosa/metabolismo , Ovário/metabolismo , Células de Sertoli/metabolismo , Animais , Dimerização , Feminino , Fertilidade , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Células Germinativas/metabolismo , Gonadotropinas/metabolismo , Humanos , Masculino , Camundongos , Ovário/embriologia , Ovário/crescimento & desenvolvimento , Hipófise/embriologia , Hipófise/crescimento & desenvolvimento , Hipófise/metabolismo , Ratos , Receptores do FSH/metabolismo , Reprodução , Maturidade Sexual , Espermatogênese/genética , Espermatogônias/citologia
5.
J Clin Endocrinol Metab ; 106(2): e534-e550, 2021 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-33119067

RESUMO

CONTEXT: Follicle-stimulating hormone (FSH) plays an essential role in gonadal function. Loss-of-function mutations in the follicle-stimulating hormone receptor (FSHR) are an infrequent cause of primary ovarian failure. OBJECTIVE: To analyze the molecular physiopathogenesis of a novel mutation in the FSHR identified in a woman with primary ovarian failure, employing in vitro and in silico approaches, and to compare the features of this dysfunctional receptor with those shown by the trafficking-defective D408Y FSHR mutant. METHODS: Sanger sequencing of the FSHR cDNA was applied to identify the novel mutation. FSH-stimulated cyclic adenosine monophosphate (cAMP) production, ERK1/2 phosphorylation, and desensitization were tested in HEK293 cells. Receptor expression was analyzed by immunoblotting, receptor-binding assays, and flow cytometry. Molecular dynamics simulations were performed to determine the in silico behavior of the mutant FSHRs. RESULTS: A novel missense mutation (I423T) in the second transmembrane domain of the FSHR was identified in a woman with normal pubertal development but primary amenorrhea. The I423T mutation slightly impaired plasma membrane expression of the mature form of the receptor and severely impacted on cAMP/protein kinase A signaling but much less on ß-arrestin-dependent ERK1/2 phosphorylation. Meanwhile, the D408Y mutation severely affected membrane expression, with most of the FSH receptor located intracellularly, and both signal readouts tested. Molecular dynamics simulations revealed important functional disruptions in both mutant FSHRs, mainly the loss of interhelical connectivity in the D408Y FSHR. CONCLUSIONS: Concurrently, these data indicate that conformational differences during the inactive and active states account for the distinct expression levels, differential signaling, and phenotypic expression of the I423T and D408Y mutant FSHRs.


Assuntos
Insuficiência Ovariana Primária/genética , Receptores do FSH/genética , Adulto , Amenorreia/genética , Amenorreia/metabolismo , Substituição de Aminoácidos , Família , Feminino , Hormônio Foliculoestimulante/farmacologia , Células HEK293 , Humanos , Isoleucina/genética , Mutação com Perda de Função/genética , Modelos Moleculares , Mutação de Sentido Incorreto , Linhagem , Insuficiência Ovariana Primária/metabolismo , Receptores do FSH/agonistas , Receptores do FSH/química , Receptores do FSH/metabolismo , Treonina/genética
6.
Histol Histopathol ; 35(9): 961-971, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32369181

RESUMO

Ovarian cancer is the first cause of death for gynecological malignances in developed countries and around 80% correspond to Epithelial Ovarian Cancer (EOC). Overexpression of Nerve Growth Factor (NGF) and its high affinity receptor TRKA are involved in EOC progression, modulating several oncogenic processes such as angiogenesis by the increase of Vascular Endothelial Growth Factor (VEGF). FSH receptors (FSH-R) are present in EOC, but their changes and contribution during EOC progression are still not thoroughly known. The aims of this study were to evaluate the abundance of FSH receptors during EOC differentiation and to determine whether FSH modulates oncoproteins such as NGF and VEGF in ovarian cells. FSH-R expression in EOC tissues and cell lines (A2780, poorly differentiated EOC cells and HOSE, non-tumoral ovarian surface epithelial cells) were measured by RT-PCR and laser capture of epithelial cells from EOC samples by qPCR. FSH-R protein levels were evaluated by immunohisto/cytochemistry. Additionally, ovarian explants and ovarian cell lines were stimulated with FSH and/or FSH-R inhibitor to assess NGF and VEGF mRNA and protein levels. The results showed that FSH-R levels decreased during EOC progression, nevertheless these receptors are still present in poorly differentiated EOC. FSH increased NGF expression in ovarian cells, which was prevented using a FSH-R inhibitor. Similarly, in ovarian cancer explants, FSH increased NGF and VEGF mRNA, as well as NGF protein levels. These results suggest that FSH would display a key role not only in initial stages of EOC, but also in late stages of this disease, by modulation of NGF and VEGF levels in EOC cells.


Assuntos
Cistadenocarcinoma Seroso/metabolismo , Células Epiteliais/efeitos dos fármacos , Hormônio Foliculoestimulante/farmacologia , Fator de Crescimento Neural/metabolismo , Neoplasias Ovarianas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular , Cistadenocarcinoma Seroso/patologia , Células Epiteliais/metabolismo , Feminino , Humanos , Neoplasias Ovarianas/patologia , Ovário/efeitos dos fármacos , Ovário/metabolismo , Receptores do FSH/metabolismo
7.
Endocrinology ; 159(8): 3020-3035, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982321

RESUMO

FSH is synthesized in the pituitary by gonadotrope cells. By binding to and interacting with its cognate receptor [FSH receptor (FSHR)] in the gonads, this gonadotropin plays a key role in the control of gonadal function and reproduction. Upon activation, the FSHR undergoes conformational changes leading to transduction of intracellular signals, including dissociation of G protein complexes into components and activation of several associated interacting partners, which concertedly regulate downstream effectors. The canonical Gs/cAMP/protein kinase A pathway, considered for a long time as the sole effector of FSHR-mediated signaling, is now viewed as one of several mechanisms employed by this receptor to transduce intracellular signals in response to the FSH stimulus. This complex network of signaling pathways allows for a fine-tuning regulation of the gonadotropic stimulus, where activation/inhibition of its multiple components vary depending on the cell context, cell developmental stage, and concentration of associated receptors and corresponding ligands. Activation of these multiple signaling modules eventually converge to the hormone-integrated biological response, including survival, proliferation and differentiation of target cells, synthesis and secretion of paracrine/autocrine regulators, and, at the molecular level, functional selectivity and differential gene expression. In this mini-review, we discuss the complexity of FSHR-mediated intracellular signals activated in response to ligand stimulation. A better understanding of the signaling pathways involved in FSH action might potentially influence the development of new therapeutic strategies for reproductive disorders.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Receptores do FSH/metabolismo , Reprodução , Transdução de Sinais , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Expressão Gênica , Humanos , Ligantes
8.
Reprod Fertil Dev ; 29(12): 2496-2505, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28641706

RESUMO

Bisphenol A (BPA) is a synthetic endocrine-disrupting chemical of high prevalence in the environment, which may affect the function of the hypothalamic-pituitary-testis (HPT) axis in adult rats. The aim of the present study was to evaluate whether exposure to BPA during hypothalamic sexual differentiation at doses below the reproductive no observable adverse effect level of the World Health Organization causes changes in the regulation of the HPT axis. For this, 0.5 or 5mgkg-1 BPA was injected subcutaneously to the mothers from gestational day 18 to postnatal day (PND) 5. In adulthood (PND90), the mRNA expression of genes related to HPT axis was evaluated in hypothalamus, pituitary and testis. Hypothalamic expression of gonadotrophin-releasing hormone (Gnrh) and estrogen receptor 2 (Esr2) mRNA was increased in both BPA-treated groups compared to control group. In the pituitary, follicle stimulating hormone beta subunit (Fshb) and androgen receptor (Ar) mRNA expression was increased compared to control group in rats treated with 0.5mgkg-1 of BPA, whereas estrogen receptor 1 (Esr1) mRNA expression was only increased in the group treated with 5mgkg-1of BPA, compared to control group. In the testis, there was increased expression of FSH receptor (Fshr) and inhibin beta B subunit (Inhbb) transcripts only in rats treated with 0.5mgkg-1 of BPA. Serum testosterone and LH concentrations were increased in the group treated with 5mgkg-1of BPA. The results of the present study demonstrate for the first time that perinatal exposure to low doses of BPA during the critical period of hypothalamic sexual differentiation modifies the activity of the HPT axis in the offspring, with consequences for later life in adult rats.


Assuntos
Compostos Benzidrílicos/farmacologia , Disruptores Endócrinos/farmacologia , Expressão Gênica/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Fenóis/farmacologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Maturidade Sexual/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Receptor alfa de Estrogênio/metabolismo , Feminino , Subunidade beta do Hormônio Folículoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Gravidez , Ratos , Receptores do FSH/metabolismo , Maturidade Sexual/fisiologia , Testículo/metabolismo
9.
Reprod Fertil Dev ; 29(6): 1144-1154, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27166082

RESUMO

The aim of the present study was to evaluate the effect of anti-Müllerian hormone (AMH), with and without FSH, on the in vitro development of isolated caprine preantral follicles, as well as follicular steroid production and mRNA levels of AMH, hormone receptors (AMH and FSH), CYP19A1 (cytochrome P450, family 19, subfamily A, polypeptide 1), CYP17 (cytochrome P450, family 17, subfamily A, polypeptide 1), HSD3B (3-beta-hydroxysteroid dehydrogenase) and Myc (myelocytomatosis oncogene). Isolated secondary follicles were cultured in minimum essential medium alpha (α-MEM+) alone or supplemented with 50ng mL-1 AMH and/or 100ng mL-1 FSH added sequentially on different days of culture. Follicles were cultured for a total of 18 days, with different media during the first (Days 0-9) and second (Days 10-18) halves of the culture period, resulting in six treatment groups, as follows: α-MEM+/α-MEM+, FSH/FSH, AMH/AMH, AMH+FSH/AMH+FSH, AMH/FSH, and FSH/AMH. Follicle development was evaluated on the basis of follicular growth, oocyte maturation and steroid secretion. There was a decrease in follicular growth rate in the AMH, AMH+FSH and AMH/FSH treatment groups compared with α-MEM+ and FSH treatment groups (P<0.05). However, the different culture conditions had no effect on rates of meiotic resumption and steroid secretion (P>0.05). Moreover, follicles cultured in the presence of FSH had lower levels of AMH receptor type II (AMHRII) mRNA compared with non-cultured control (freshly isolated follicles), and the AMH and AMH/FSH treatment groups. In conclusion, AMH reduces the follicular growth rate of isolated goat preantral follicles in vitro without affecting follicular survival.


Assuntos
Hormônio Antimülleriano/metabolismo , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Oogênese , Folículo Ovariano/metabolismo , Receptores do FSH/agonistas , Receptores de Peptídeos/agonistas , Receptores de Fatores de Crescimento Transformadores beta/agonistas , Matadouros , Animais , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/farmacologia , Brasil , Bovinos , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cruzamentos Genéticos , Estradiol/metabolismo , Feminino , Hormônio Foliculoestimulante/genética , Hormônio Foliculoestimulante/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Cabras , Humanos , Oogênese/efeitos dos fármacos , Folículo Ovariano/citologia , Folículo Ovariano/efeitos dos fármacos , Progesterona/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Testosterona/metabolismo , Técnicas de Cultura de Tecidos
10.
J Endocrinol ; 232(1): 97-105, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27856623

RESUMO

Previous work has demonstrated that the increase in the activity of sympathetic nerves, which occurs during the subfertility period in female rats, causes an increase in follicular cyst development and impairs follicular development. In addition, the increase in ovarian sympathetic activity of aged rats correlates with an increased expression of kisspeptin (KISS1) in the ovary. This increase in KISS1 could participate in the decrease in follicular development that occurs during the subfertility period. We aimed to determine whether the blockade of ovarian sympathetic tone prevents the increase in KISS1 expression during reproductive aging and improves follicular development. We performed 2 experiments in rats: (1) an in vivo blockade of beta-adrenergic receptor with propranolol (5.0 mg/kg) and (2) an ovarian surgical denervation to modulate the sympathetic system at these ages. We measured Kisspeptin and follicle-stimulating hormone receptor (FSHR) mRNA and protein levels by qRT-PCR and western blot and counted primordial, primary and secondary follicles at 8, 10 and 12 months of age. The results showed that ovarian KISS1 decreased but FSHR increased after both propranolol administration and the surgical denervation in rats of 8, 10 and 12 months of age. An increase in FSHR was related to an increase in the number of smaller secondary follicles and a decreased number of primordial follicles at 8, 10 and 12 months of age. These results suggest that intraovarian KISS1 is regulated by sympathetic nerves via a beta-adrenergic receptor and participates locally in ovarian follicular development in reproductive aging.


Assuntos
Envelhecimento/metabolismo , Regulação da Expressão Gênica , Kisspeptinas/metabolismo , Ovário/metabolismo , Sistema Nervoso Simpático/metabolismo , Antagonistas Adrenérgicos beta/farmacologia , Animais , Feminino , Kisspeptinas/genética , Ovário/efeitos dos fármacos , Propranolol/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores do FSH/genética , Receptores do FSH/metabolismo , Sistema Nervoso Simpático/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA