Time filter

Source Type

Molina I.,Polytechnic University of Valencia | Gomez J.,Polytechnic University of Valencia | Balasch S.,Polytechnic University of Valencia | Pellicer N.,Instituto Universitario | And 2 more authors.
Reproductive Biology and Endocrinology

Background: During cytoplasmic oocyte maturation, Ca2+ currents are vital for regulating a broad range of physiological processes. Recent studies have demonstrated that DMSO and EG cause large transient increases in intracellular Ca2+ in mouse oocytes. The CP used in vitrifying protocols also increases the intracellular calcium transient. The aim of this study is to evaluate the effects of vitrifying time (before and after IVM) and exposure to the vitrification solutions and ionomycin on oocyte quality and embryonic development. Methods: 221 GV-oocytes unsuitable for IVF-ICSI cycles were randomly distributed into one of the following three groups. G1 (control group): 41 GV-oocytes IVM until MII; G2: 43 oocytes vitrified at GV stage and IVM until MII stage and G3: 53 GV-oocytes IVM until MII and then vitrified. In order to clarify the effect of vitrification solutions (VS) on human oocyte IVM through the intracellular Ca2+ oscillation, the following two groups were also included. G4: 43 GV-oocytes exposed to VS and IVM until MII; and G5: 41 GV-oocytes exposed to ionomycin and IVM until MII. All GV-oocytes that reached MII-stage were parthenogenetically activated to assess oocyte viability. IVM was performed in IVF-medium (24-48h). Chemical treatment (ionomycin) and osmotic treatment (vitrification solutions) were performed without liquid-N2 immersion. The following rates were evaluated: survival (SR), in-vitro maturation (IVMR), activation (AR), development to 2-cell (DRC), development to morula (DRCM) and development to blastocyst (DRB). Ratios between the different treatment groups were compared using contingency tables analysis (chi-square test). Results: A high survival rate was obtained in G2 (95.5%) and G4 (96.6%). In-vitro maturation rate was significantly higher for G4 (86%) and G2 (83.7%) compared to G1 (63.4%), G3 (56.6%) and G5 (48.8%). DRCM was significantly higher for G1 and G2 compared to G3 (G1: 15.8%, G2: 20.7% and G3: 0%). DRB was only obtained for the oocytes vitrified before IVM (G2: 3.4%). AR was also significantly higher for G2 and G4 compared to G5 (G2: 80.5%, G4: 86.5% and G5: 55%). DRCM and DRB were only obtained in G2 and G4. DRCM was significantly higher for oocytes vitrified at GV stage (G2) and for oocytes exposed to the VS in G4 compared to the oocytes exposed to the ionomycin in G5 (G2: 20.7%; G4: 37.5% and G5: 0%). Conclusions: Vitrifying GV-oocytes improves their IVM. Further investigation could look to increase the oocyte pool and improve fertility preservation options. © 2016 Molina et al. Source

Marzal Escriva A.,Polytechnic University of Valencia | Marzal Escriva A.,Institute Investigacion Sanitario La Fe | Marzal Escriva A.,Instituto Universitario | Diaz-Garcia C.,Polytechnic University of Valencia | And 7 more authors.
Journal of Clinical Endocrinology and Metabolism

Context: A low response to controlled ovarian hyperstimulation implies a reduced number of embryos and impaired pregnancy rate. Follicular priming with steroids before controlled ovarian hyperstimulation has been suggested to improve the subsequent ovarian response. Objective:Thepurposeofthisstudywastodeterminethebestfollicularprimingprotocolinlowresponders and to investigate the intrafollicular mechanisms triggered by steroid hormone priming. Design: This was a single-center, randomized, parallel, open-label, controlled trial, in two phases. Setting: The setting was a university-based in vitro fertilization unit. Patients: Potential low responders (n=99) underwent a first intracytoplasmic sperm injection cycle. Confirmed low responders (n=66) were randomized to different priming protocols before a new intracytoplasmic sperm injection. Interventions: Randomized patients underwent one of the following priming strategies: transdermal testosterone (20mu;g/kg/d), transdermal estradiol (200μg/d), orcombinedestrogensandoral contraceptive pills (30mu;g of ethinyl estradiol plus 150mu;g of desogestrel administered during the luteal phase of two consecutive cycles) and 4 mg/d of estradiol valerate during the follicular phase between them. Main Outcomes Measures: Metaphase II (MII) oocytes were retrieved. Gene expression levels in the granulosa cells of steroidogenesis enzymes and FSH, LH, and androgen receptors were measured. Results: The number of retrieved MII oocytes did not differ between the interventional groups (testosterone, 2.2±2.0; estrogen, 2.7±1.7; and combined estrogens and oral contraceptive pills, 2.0±1.3; not significant). Compared with those in nonprimed cycles, estradiol pretreatment yielded more MII oocytes (primed, 2.7±1.7; nonprimed, 1.6±1.2; P .029) although the clinical pregnancy rate was higher in patients treated with testosterone (P .003). Testosterone pretreatment increased androgen receptor expression (P<028) compared with that for the previous cycle without priming. Conclusions: The results of the present trial do not support the superiority of one priming strategy over the others. Copyright © 2015 by the Endocrine Society. Source

Herraiz S.,Institute Investigacion Sanitario La Fe | Herraiz S.,Polytechnic University of Valencia | Novella-Maestre E.,Institute Investigacion Sanitario La Fe | Novella-Maestre E.,Polytechnic University of Valencia | And 10 more authors.
Fertility and Sterility

Objective To compare slow freezing (SF) with four vitrification techniques (VT) for cryopreservation of ovarian tissue (OT) and to evaluate the best protocol for human OT in a xenograft model. Design Experimental study. Setting University hospital. Patient(s) Patients undergoing fertility preservation. Animal(s) Ovariectomized nude mice. Intervention(s) Cryopreservation of bovine OT after SF and four VTs (VT1, VT2, VT3, and VT4) by combining two cryoprotectant vitrification solutions (VS1 and VS2) and two devices (metallic grid and ethyl vinyl acetate bag), after which the cryopreservation of human OT by SF and VT1 and xenograft into nude mice. Main Outcome Measure(s) Follicular densities, proliferation, vascularization, fibrosis, apoptosis, tissue viability. Result(s) The in vitro study in bovine OT showed a lower percentage of quiescent follicles in the SF group but not in the vitrification groups (VT1-VT4). Apoptosis increased and cell proliferation decreased in all the experimental groups except VT1 (20% ethylene glycol, 20% dimethyl sulfoxide, 0.5 M sucrose, and 20% synthetic serum substitute in HEPES-buffered M199 culture media with Cryotissue metallic grids). Tissue viability was diminished in VT3, and the SF-xenografted human samples showed reduced primordial and secondary densities and unbalanced follicular populations when compared with fresh and VT1 tissue. Conclusion(s) VT1 offers similar conditions to fresh tissue for follicular density, proliferation, viability, and cell death and preserves a larger population of quiescent follicles than SF after transplantation, thus ensuring the maintenance of graft potential fertility. © 2014 American Society for Reproductive Medicine, Published by Elsevier Inc. Source

Novella-Maestre E.,Polytechnic University of Valencia | Novella-Maestre E.,Institute Investigacion Sanitario La Fe | Herraiz S.,Institute Investigacion Sanitario La Fe | Vila-Vives J.M.,Institute Investigacion Sanitario La Fe | And 6 more authors.
Fertility and Sterility

Objective: To investigate the effect of antiangiogenic treatment on experimental endometriotic lesion nerve fibers. Design: Heterologous mouse model of endometriosis. Setting: University Institute IVI, University Hospital La Fe. Animal(s): Ovariectomized nude mice (n = 16) receiving human endometrial fragments from oocyte donors (n = 4). Intervention(s): Endometrium fragments stuck in the peritoneum of 5-week-old female nude mice treated with vehicle (n = 8) and antiangiogenic agent cabergoline (n = 8; Cb2, 0.05 mg/kg/day) for 14 days. Main Outcome Measure(s): Immunofluorescence analysis of von-Willebrand factor (vWF) and vascular smooth muscle cells (αSMA) for evaluating the number of immature blood vessels (IBV) and microvascular density (MVD); immunochemical analysis of protein-gene product 9.5 (PGP 9.5) to assess nerve fibers density (NFD), and blue toluidine staining to confirm presence of mast cells and macrophages in endometriotic lesions. Result(s): All the results were quantified by morphometric techniques. The IBV, NFD, and number of macrophages and mast cells were statistically significantly decreased in the Cb2-treated group when compared with controls. Conclusion(s): Antiangiogenic treatment statistically significantly diminishes new blood vessel formation after macrophage, mast cell, and nerve fiber reduction, providing a rationale to test antiangiogenic agents as a novel therapeutic approach to severe pelvic pain associated with human peritoneal endometriosis. Copyright © 2012 American Society for Reproductive Medicine, Published by Elsevier Inc. Source

Novella-Maestre E.,Polytechnic University of Valencia | Novella-Maestre E.,Institute Investigacion Sanitario La Fe | Herraiz S.,Institute Investigacion Sanitario La Fe | Herraiz S.,Polytechnic University of Valencia | And 7 more authors.

Introduction: In vitro activation and growth of primordial dormant follicles to produce fertilizable oocytes would provide a useful instrument for fertility preservation. The employment of Phosphatase and TENsin homolog (PTEN) inhibitors, in combination with Protein kinase B (Akt) stimulating molecules, has been previously employed to increase follicular activation through the stimulation of the PTEN-Akt pathway. Methods: We aim to establish improved in vitro activation also for cancer patients whose ovarian tissue has already been cryopreserved. Fresh and previously cryopreserved human ovarian cortex were exposed to short-term, low-concentration and ovary-specific treatment with only a PTEN inhibitor. Results: Our in vitro activation protocol enhances the activation mechanisms of primordial follicles in both fresh and cryopreserved samples, and enlarges growing populations without inducing apoptosis in either follicles or the surrounding stroma. Treatment augments estradiol secretion and restores the expression levels of the previously diminished Anti-Müllerian hormone by means of cryopreservation procedures. Genomic modulation of the relative expression of PTEN pathway genes was found in treated samples. Conclusion: The in vitro activation protocol offers new alternatives for patients with cryopreserved tissue as it increases the pool of viable activated follicles available for in vitro growth procedures. The combination of ovarian tissue cryopreservation and in vitro activation of primordial follicles, the main ovarian reserve component, will be a major advancement in fertility preservation. © 2015 Novella-Maestre et al. Source

Discover hidden collaborations