60 resultados para Ovarian steroidogenesis
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
Introduction: Throughout follicular growth and subsequent corpus luteum formation the leukocyte number increases and follicular vascularisation changes. These processes are enhanced under exogenous stimulation with gonadotropins. Cytokines released by leukocytes contribute to further recruitment and vascularisation of the follicle, and they play an important role in regulating ovarian steroidogenesis by influencing theca and granulosa–lutein cell function. Changes in cytokine and vascular endothelial growth factor (VEGF) concentrations in the ovary as a consequence of gonadotropin stimulation may negatively influence oocyte quality. In this project we have compared the intrafollicular production of inflammatory cytokines and growth factors between natural IVF cycles (NC) and classical, gonadotropin-stimulated IVF cycles (gsIVF). Material and Methods: Serum on the day of oocyte retrieval and follicular fluid (FF) were collected in 37 NC and 39 gsIVF cycles. Thirteen women within this population underwent one NC and one gsIVF cycle each. A total of 14 cytokines from Bio-Plex panels I and II were determined in matched serum and FF samples using Luminex xMAP technology on the Bio-Plex(R) platform, using the serum protocol. Results: Tumour necrosis factor-alpha, RANTES, eotaxin and interferon-gamma-induced protein-10 levels were lower in FF than in serum, and thus not further investigated. Interleukin (IL)-6, -8, -10, -15, -18, monocyte chemotactic protein-1 (MCP-1), VEGF and leukaemia inhibitory factor (LIF) showed higher median concentrations in FF than in serum, indicating possible ovarian production. Moreover, most of these showed higher evels in the gsIVF than in the NC groups in the serum, but not in the follicular fluid. IL-8 was reduced in gsIVF cycles. Conclusion: The fact that serum but not FF levels of the studied cytokines were higher in the stimulated than in the natural cycles can be attributed to the increased number of active follicles present after controlled ovarian stimulation.
Resumo:
Steroidogenic factor 1 (NR5A1/SF-1) mutations usually manifest in 46,XY individuals with variable degrees of disordered sex development and in 46,XX women with ovarian insufficiency. So far, there is no genotype-phenotype correlation. The broad spectrum of phenotype with NR5A1 mutations may be due to a second hit in a gene with similar function to NR5A1/SF-1. Liver receptor homologue-1 (LRH-1/NR5A2) might be a good candidate. We performed in vitro studies for the interplay between SF-1, LRH-1 and DAX-1, expression profiles in human steroidogenic tissues, and NR5A2 genetic studies in a cohort (11 patients, 8 relatives, 11 families) harboring heterozygote NR5A1/SF-1 mutations. LRH-1 isoforms transactivate the CYP17A1 and HSD3B2 promoters similarly to SF-1 and compensate for SF-1 deficiency. DAX-1 inhibits SF-1- and LRH-1-mediated transactivation. LRH-1 is found expressed in human adult and fetal adrenals and testes. However, no NR5A2/LRH-1 mutations were detected in 14 individuals with heterozygote NR5A1/SF-1 mutations. These findings demonstrate that in vitro LRH-1 can act like SF-1 and compensate for its deficiency. Expression of LRH-1 in fetal testis suggests a role in male gonadal development. However, as we found no NR5A2/LRH-1 mutations, the 'second genetic hit' in SF-1 patients explaining the broad phenotypic variability remains elusive.
Resumo:
This pilot study evaluated whether combination of partial removal of ovarian tissue for cryobanking followed by ovarian stimulation and cryopreservation of oocytes can improve the efficacy of fertility preservation without further delaying cancer treatment. Initial partial removal of ovarian tissue did not substantially affect the average number and quality of retrieved oocytes after ovarian stimulation in this study.
Resumo:
Ovarian stimulation and cryopreservation of fertilized oocytes before cancer therapy is the best established and efficient fertility preservation technique and should still be considered before chemotherapy. Within a short time frame of 2 weeks, between 8.6 (18-25 y) and 5.1 (36-40 y) fertilized oocytes can be cryopreserved.
Resumo:
To evaluate safety and fertility outcome after assisted conception in patients who were treated conservatively for a borderline ovarian tumor (BOT).
Resumo:
This study examined the possible presence of malignant cells in ovarian cortex from patients with ovarian tumors after xenografting of the ovarian tissue into severe combined immunodeficiency mice. None of the mice presented symptoms of reintroduced malignancy nor did microscopic and immunohistochemical evaluation of the grafts raise any suspicion of residual malignant disease.
Resumo:
Several members of the human kallikrein-related peptidase family, including KLK6, are up-regulated in ovarian cancer. High KLK6 mRNA or protein expression, measured by quantitative polymerase chain reaction and enzyme-linked immunoassay, respectively, was previously found to be associated with a shortened overall and progression-free survival (OS and PFS, respectively). In the present study, we aimed at analyzing KLK6 protein expression in ovarian cancer tissue by immunohistochemistry. Using a newly developed monospecific polyclonal antibody, KLK6 immunoexpression was initially evaluated in normal tissues. We observed strong staining in the brain and moderate staining in the kidney, liver, and ovary, whereas the pancreas and the skeletal muscle were unreactive, which is in line with previously published results. Next, both tumor cell- and stromal cell-associated KLK6 immunoexpression were analyzed in tumor tissue specimens of 118 ovarian cancer patients. In multivariate Cox regression analysis, only stromal cell-associated expression, besides the established clinical parameters FIGO stage and residual tumor mass, was found to be statistically significant for OS and PFS [high vs. low KLK6 expression; hazard ratio (HR), 1.92; p=0.017; HR, 1.80; p=0.042, respectively]. These results indicate that KLK6 expressed by stromal cells may considerably contribute to the aggressiveness of ovarian cancer.
Resumo:
Metformin is treatment of choice for the metabolic consequences seen in polycystic ovary syndrome for its insulin-sensitizing and androgen-lowering properties. Yet, the mechanism of action remains unclear. Two potential targets for metformin regulating steroid and glucose metabolism are AMP-activated protein kinase (AMPK) signaling and the complex I of the mitochondrial respiratory chain. Androgen biosynthesis requires steroid enzymes 17α-Hydroxylase/17,20 lyase (CYP17A1) and 3β-hydroxysteroid dehydrogenase type 2 (HSD3B2), which are overexpressed in ovarian cells of polycystic ovary syndrome women. Therefore, we aimed to understand how metformin modulates androgen production using NCI-H295R cells as an established model of steroidogenesis. Similar to in vivo situation, metformin inhibited androgen production in NCI cells by decreasing HSD3B2 expression and CYP17A1 and HSD3B2 activities. The effect of metformin on androgen production was dose dependent and subject to the presence of organic cation transporters, establishing an important role of organic cation transporters for metformin's action. Metformin did not affect AMPK, ERK1/2, or atypical protein kinase C signaling. By contrast, metformin inhibited complex I of the respiratory chain in mitochondria. Similar to metformin, direct inhibition of complex I by rotenone also inhibited HSD3B2 activity. In conclusion, metformin inhibits androgen production by mechanisms targeting HSD3B2 and CYP17-lyase. This regulation involves inhibition of mitochondrial complex I but appears to be independent of AMPK signaling.
Resumo:
Steroidogenic factor-1 (SF-1/NR5A1) is a nuclear receptor that regulates adrenal and reproductive development and function. NR5A1 mutations have been detected in 46,XY individuals with disorders of sexual development (DSD) but apparently normal adrenal function and in 46,XX women with normal sexual development yet primary ovarian insufficiency (POI).
Resumo:
To study whether the ovarian reserve in female lymphoma patients is already reduced before the start of chemotherapy.
Resumo:
The aim of this study was to evaluate serum and peritoneal fluid (PF) glycodelin-A concentrations in women with ovarian endometriosis. Ninety-nine matched pairs of serum and PF samples were included in our study. The case group comprised 57 women with ovarian endometriosis and the control group 42 healthy women undergoing sterilization or patients with benign ovarian cysts. Glycodelin-A concentrations were measured using ELISA. Endometriosis patients had significantly higher serum and PF glycodelin-A concentrations compared to controls, and this increase was observed in both proliferative and secretory cycle phases. Glycodelin-A concentrations were more than 10-fold higher in PF than in serum and correlated with each other. Intensity and frequency of menstrual pain positively correlated with glycodelin-A concentrations. Sensitivity and specificity of glycodelin-A as a biomarker for ovarian endometriosis were 82.1% and 78.4% in serum, and 79.7% and 77.5% in PF, respectively. These results indicate that Glycodelin-A has a potential role as a biomarker to be used in combination with other, independent marker molecules.