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1.
BMC Pregnancy Childbirth ; 18(1): 272, 2018 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-29954364

RESUMEN

BACKGROUND: Single nucleotide polymorphism of the follicle-stimulating hormone (FSH) receptor (FSHR) is an important marker of ovarian function. However, its role in female fecundity remains debatable. The aim of the study to assess the relationship of FSHR polymorphism of Serine/Serine, Asparagine/Asparagine and Asparagine/Serine variants directly against the time-to-pregnancy (TTP) in women. METHODS: Data were collected from 291 consecutive selected post-partum Caucasians using this criterion: ethnicity, age between 21 and 34-year-old new mothers and, 0-3 days after delivery of newborns in the Klaipeda University Hospital, Lithuania. Questionnaires on factors associated with conception were given to patients, and blood samples were collected for genomic DNA extractions as well as for analysis of follicle-stimulating hormone receptor gene polymorphism. Odds ratios (OR) and 95% confidence intervals (CI) for time-to-pregnancy were estimated by multivariate logistic regression. Women with unplanned pregnancies and those who received assisted reproductive technologies were not included in the study. RESULTS: After adjustment for other possible factors, increased risk for time-to-pregnancy of 12 or more months was associated with: Serine/Serine polymorphism variant (OR = 1.38, 95% CI 1.56-2.71, p = 0.007), age of 30 or more years (OR = 1.95, 95% CI 1.25-2.71, p = 0.015), gynaecological diseases in the past (OR = 2.21, 95% CI 1.12-5.74, p = 0.027), prior contraception use (OR = 1.87, 95% CI 1.14-3.64, p = 0.016), and fertility problems in the past (OR = 1.57, 95% CI 1.16-4.76, p = 0.019). CONCLUSION: The results suggest a possible relationship of FSH receptor gene Serine/Serine variant for the lower possibility of conception during the first 12 months of planned conception.


Asunto(s)
Receptores de HFE/genética , Tiempo para Quedar Embarazada/genética , Adulto , Estudios Transversales , Femenino , Genotipo , Humanos , Lituania , Polimorfismo de Nucleótido Simple , Embarazo , Pronóstico , Medición de Riesgo/métodos , Sensibilidad y Especificidad , Adulto Joven
2.
Endocr Connect ; 12(3)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36598290

RESUMEN

The 3rd International Workshop on Klinefelter Syndrome, Trisomy X, and 47,XYY syndrome was held in Leiden, the Netherlands, on September 12-14, 2022. Here, we review new data presented at the workshop and discuss scientific and clinical trajectories. We focus on shortcomings in knowledge and therefore point out future areas for research. We focus on the genetics and genomics of supernumerary sex chromosome syndromes with new data being presented. Most knowledge centre specifically on Klinefelter syndrome, where aspects on testosterone deficiency and the relation to bone, muscle and fat were discussed, as was infertility and the treatment thereof. Both trisomy X and 47,XYY syndrome are frequently affected by infertility. Transitioning of males with Klinefelter syndrome was addressed, as this seemingly simple process in practise is often difficult. It is now realized that neurocognitive changes are pervasive in all supernumerary sex chromosome syndromes, which were extensively discussed. New intervention projects were also described, and exciting new data concerning these were presented. Advocacy organizations were present, describing the enormous burden carried by parents when having to explain their child's specific syndrome to most professionals whenever in contact with health care and education systems. It was also pointed out that most countries do not have health care systems that diagnose patients with supernumerary sex chromosome syndromes, thus pinpointing a clear deficiency in the current genetic testing and care models. At the end of the workshop, a roadmap towards the development of new international clinical care guidelines for Klinefelter syndrome was decided.

3.
Cells Tissues Organs ; 196(6): 543-54, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22739409

RESUMEN

The marmoset monkey is a valuable model in reproductive medicine. While previous studies have evaluated germ cell dynamics in the postnatal marmoset, the features of testicular somatic cells remain largely unknown. Therefore, the aim of this study was to establish marmoset-specific markers for Sertoli and peritubular cells (PTCs) and to compare protocols for the enrichment and culture of testicular cell types. Immunohistochemistry of Sertoli and PTC-specific markers - anti-müllerian hormone (AMH), vimentin (VIM), α-smooth muscle actin (SMA) - was performed and corresponding RNA expression profiles were established by quantitative PCR analysis (SOX9,AMH, FSHR,VIM, and SMA). For these analyses, testicular tissue from newborn (n = 4), 8-week-old (n = 4) and adult (n = 3) marmoset monkeys was used. Protocols for the enrichment and culture of testicular cell fractions from the 8-week-old marmoset monkeys (n = 3) were evaluated and cells were analyzed using germ cell- and somatic cell-specific markers. The expression of AMH, VIM and SMA reflects the proportion and differentiation status of Sertoli and PTCs at the RNA and the protein levels. While applied protocols did not support the propagation of germ cells in vitro, our analyses revealed that PTCs maintain their proliferative potential and constitute the dominant cell type after short- and long-term culture. Expression of functionally meaningful testicular somatic markers is similar in the human and the marmoset monkey, indicating that this primate can indeed be used as model for human testicular development. The PTC culture system established in this study will facilitate the identification of factors influencing male sex differentiation and spermatogenesis.


Asunto(s)
Callithrix/anatomía & histología , Células Germinativas/citología , Células de Sertoli/citología , Testículo/citología , Animales , Animales Recién Nacidos , Biomarcadores/metabolismo , Diferenciación Celular/fisiología , Células Cultivadas , Humanos , Inmunohistoquímica , Masculino , Testículo/embriología
4.
Front Endocrinol (Lausanne) ; 12: 780403, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992580

RESUMEN

Introduction and Objectives: About 30-75% of infertile men are diagnosed with idiopathic infertility, thereby lacking major causative factors to explain their impaired fertility status. In this study, we used a large cohort of idiopathic infertile men to determine whether subgroups could be identified by an unbiased clustering approach and whether underlying etiologic factors could be delineated. Patients and Methods: From our in-house database Androbase®, we retrospectively selected patients (from 2008 to 2018) with idiopathic male infertility (azoo- to normozoospermia) who fit the following selection criteria: FSH ≥ 1 IU/l, testosterone ≥ 8 nmol/l, ejaculate volume ≥ 1.5 ml. Patients with genetic abnormalities or partners with female factors were excluded.For the identified study population (n=2742), we used common andrologic features (somatic, semen and hormonal parameters, including the FSHB c.-211G>T (rs10835638) single nucleotide polymorphism) for subsequent analyses. Cluster analyses were performed for the entire study population and for two sub-cohorts, which were separated by total sperm count (TSC) thresholds: Cohort A (TSC ≥ 1 mill/ejac; n=2422) and Cohort B (TSC < 1 mill/ejac; n=320). For clustering, the partitioning around medoids method was employed, and the quality was evaluated by average silhouette width. Results: The applied cluster approach for the whole study population yielded two separate clusters, which showed significantly different distributions in bi-testicular volume, FSH and FSHB genotype. Cluster 1 contained all men homozygous for G (wildtype) in FSHB c.-211G>T (100%), while Cluster 2 contained most patients carrying a T allele (>96.6%). In the analyses of sub-cohorts A/B, two clusters each were formed too. Again, the strongest segregation markers between the respective clusters were bi-testicular volume, FSH and FSHB c.-211G>T. Conclusion: With this first unbiased approach for revealing putative subgroups within a heterogenous group of idiopathic infertile men, we did indeed identify distinct patient clusters. Surprisingly, across all diverse phenotypes of infertility, the strongest segregation markers were FSHB c.-211G>T, FSH, and bi-testicular volume. Further, Cohorts A and B were significantly separated by FSHB genotype (wildtype vs. T-allele carriers), which supports the notion of a contributing genetic factor. Consequently, FSHB genotyping should be implemented as diagnostic routine in patients with idiopathic infertility.


Asunto(s)
Hormona Folículo Estimulante de Subunidad beta/genética , Genotipo , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/genética , Adulto , Análisis por Conglomerados , Estudios de Cohortes , Humanos , Masculino , Estudios Retrospectivos
5.
Stem Cells ; 27(1): 138-49, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18927477

RESUMEN

Several reports have documented the derivation of pluripotent cells (multipotent germline stem cells) from spermatogonial stem cells obtained from the adult mouse testis. These spermatogonia-derived stem cells express embryonic stem cell markers and differentiate to the three primary germ layers, as well as the germline. Data indicate that derivation may involve reprogramming of endogenous spermatogonia in culture. Here, we report the derivation of human multipotent germline stem cells (hMGSCs) from a testis biopsy. The cells express distinct markers of pluripotency, form embryoid bodies that contain derivatives of all three germ layers, maintain a normal XY karyotype, are hypomethylated at the H19 locus, and express high levels of telomerase. Teratoma assays indicate the presence of human cells 8 weeks post-transplantation but limited teratoma formation. Thus, these data suggest the potential to derive pluripotent cells from human testis biopsies but indicate a need for novel strategies to optimize hMGSC culture conditions and reprogramming.


Asunto(s)
Células Madre Pluripotentes/citología , Espermatogonias/citología , Biomarcadores/metabolismo , Biopsia , Diferenciación Celular , Línea Celular , Separación Celular , Forma de la Célula , Metilación de ADN , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica , Humanos , Masculino , Repeticiones de Minisatélite/genética , Células Madre Multipotentes/citología , Neuronas/citología , Factor 3 de Transcripción de Unión a Octámeros/genética , Células Madre Pluripotentes/metabolismo , Regiones Promotoras Genéticas/genética , Análisis de Secuencia de ADN , Cariotipificación Espectral , Espermatogonias/metabolismo , Sulfitos , Telomerasa/metabolismo , Testículo/citología , Testículo/metabolismo
7.
Artículo en Inglés | MEDLINE | ID: mdl-26441830

RESUMEN

The human lutropin (hLH)/choriogonadotropin (hCG) receptor (LHCGR) can be activated by binding two slightly different gonadotropic glycoprotein hormones, choriogonadotropin (CG) - secreted by the placenta, and lutropin (LH) - produced by the pituitary. They induce different signaling profiles at the LHCGR. This cannot be explained by binding to the receptor's leucine-rich-repeat domain (LRRD), as this binding is similar for the two hormones. We therefore speculate that there are previously unknown differences in the hormone/receptor interaction at the extracellular hinge region, which might help to understand functional differences between the two hormones. We have therefore performed a detailed study of the binding and action of LH and CG at the LHCGR hinge region. We focused on a primate-specific additional exon in the hinge region, which is located between LRRD and the serpentine domain. The segment of the hinge region encoded by exon10 was previously reported to be only relevant to hLH signaling, as the exon10-deletion receptor exhibits decreased hLH signaling, but unchanged hCG signaling. We designed an advanced homology model of the hormone/LHCGR complex, followed by experimental characterization of relevant fragments in the hinge region. In addition, we examined predictions of a helical exon10-encoded conformation by block-wise polyalanine (helix supporting) mutations. These helix preserving modifications showed no effect on hormone-induced signaling. However, introduction of a structure-disturbing double-proline mutant LHCGR-Q303P/E305P within the exon10-helix has, in contrast to exon10-deletion, no impact on hLH, but only on hCG signaling. This opposite effect on signaling by hLH and hCG can be explained by distinct sites of hormone interaction in the hinge region. In conclusion, our analysis provides details of the differences between hLH- and hCG-induced signaling that are mainly determined in the L2-beta loop of the hormones and in the hinge region of the receptor.

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