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2,246 result(s) for "Ovarian Follicle - metabolism"
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Biphasic in vitro maturation (CAPA-IVM) specifically improves the developmental capacity of oocytes from small antral follicles
PurposeTo investigate the effectiveness of a biphasic IVM culture strategy at improving IVM outcomes in oocytes from small follicles (< 6 mm) compared with routine Standard IVM in patients with polycystic ovaries.MethodsThis prospective pilot study was performed in 40 women with polycystic ovaries whose oocytes were randomized to two IVM culture methods. Patients received a total stimulation dose of 450 IU rFSH. Cumulus-oocyte complexes (COCs) from follicles < 6 mm and ≥ 6 mm were retrieved and cultured separately in either a prematuration medium with c-type natriuretic peptide followed by IVM (CAPA-IVM), or STD-IVM. Primary outcomes were maturation rate, embryo quality, and the number of vitrified day 3 embryos per patient.ResultsUse of the CAPA-IVM system led to a significant improvement in oocyte maturation (p < 0.05), to a doubling in percentage of good and top-quality day 3 embryos per COC, and to an increased number of vitrified day 3 embryos (p < 0.001), compared to STD IVM. Oocytes from follicles < 6 mm benefited most from CAPA-IVM, showing a significant increase in the amount of good and top-quality embryos compared to STD IVM. CAPA-IVM yielded significantly (p < 0.0001) less GV-arrested oocytes and larger oocyte diameters (p < 0.05) than STD IVM.ConclusionsCAPA-IVM brings significant improvements in maturation and embryological outcomes, most notably to oocytes from small antral follicles (< 6 mm), which can be easily retrieved from patients with a minimal ovarian stimulation. The study demonstrates the robustness and transferability of the CAPA-IVM method across laboratories and populations.
The effects of melatonin on follicular oxidative stress and art outcomes in women with diminished ovarian reserve: a randomized controlled trial
Background To investigate the impact of Melatonin on follicular oxidative stress and assisted reproductive technology (ART) outcomes in women with diminished ovarian reserve (DOR). Method We put 68 women with DOR who were going through ART into a randomized controlled trial. Starting on the fifth day of their menstrual cycle, we gave them either 3 mg of Melatonin or a placebo every day before stimulating their ovaries. We obtained follicular fluid during oocyte retrieval, assessed it for oxidative stress indicators, and documented ART outcomes. Results Melatonin administration markedly enhanced the quantity of oocytes retrieved, fertilization rates, and embryo quality. In addition, Melatonin changed markers of oxidative stress, specifically the levels of reduced glutathione (rGSH) and total antioxidant capacity (TAC). The Melatonin group exhibited significantly elevated biochemical pregnancy rates. Conclusion Melatonin may improve the quality of oocytes and help with reproductive technology in women with low ovarian reserves, possibly by lowering oxidative stress in the follicles.
Dehydroepiandrosterone improves follicular fluid bone morphogenetic protein-15 and accumulated embryo score of infertility patients with diminished ovarian reserve undergoing in vitro fertilization: a randomized controlled trial
Objective To evaluate the effect of dehydroepiandrosterone (DHEA) on infertility patients with diminished ovarian reserve undergoing in vitro fertilization. Methods This is a prospective study. Ninety-five patients with diminished ovarian reserve were included in this study. Of them, 42 patients were randomly allocated to the DHEA group, who received DHEA 75 mg daily for three consecutive menstrual cycles prior to IVF cycles, and 53 patients were allocated to the control group, who entered IVF cycles directly. All patients were treated with the same ovarian stimulation protocol. Follicular fluid samples from both groups were collected for bone morphogenetic protein-15 (BMP-15) and growth differentiation factor-9 (GDF-9). Fluid from the first aspirated follicle without any visible blood contamination was carefully collected. In addition, day 3 Blood samples were collected pre- and post-treatment of DHEA for serum anti-Mullerian hormone (AMH), follicle stimulating hormone (FSH) and estradiol (E 2 ) in the DHEA group. Results The level of BMP-15 in follicular fluid samples from the DHEA group was significantly higher than that of the control samples ( P= .000). Patients after DHEA treatment demonstrated a significantly higher level of AMH and a significantly lower level of FSH, E 2 compared to themselves prior to DHEA therapy ( P= .015; P= .036; P= .002; respectively). Moreover, the accumulated score of embryos was significantly higher in the DHEA group ( P= .033). Conclusions These observations confirm the beneficial effect of DHEA for infertility patients with diminished ovarian reserve. Trial registration ChiCTR-TRC-14005002
Specific deletion of AMP-activated protein kinase (α1AMPK) in murine oocytes alters junctional protein expression and mitochondrial physiology
Oogenesis and folliculogenesis are dynamic processes that are regulated by endocrine, paracrine and autocrine signals. These signals are exchanged between the oocyte and the somatic cells of the follicle. Here we analyzed the role of AMP-activated protein kinase (AMPK), an important regulator of cellular energy homeostasis, by using transgenic mice deficient in α1AMPK specifically in the oocyte. We found a decrease of 27% in litter size was observed in ZP3-α1AMPK-/- (ZP3-KO) female mice. Following in vitro fertilization, where conditions are stressful for the oocyte and embryo, ZP3-KO oocytes were 68% less likely to pass the 2-cell stage. In vivo and in cumulus-oocyte complexes, several proteins involved in junctional communication, such as connexin37 and N-cadherin were down-regulated in the absence of α1AMPK. While the two signalling pathways (PKA and MAPK) involved in the junctional communication between the cumulus/granulosa cells and the oocyte were stimulated in control oocytes, ZP3-KO oocytes exhibited only low phosphorylation of MAPK or CREB proteins. In addition, MII oocytes deficient in α1AMPK had a 3-fold lower ATP concentration, an increase in abnormal mitochondria, and a decrease in cytochrome C and PGC1α levels, suggesting perturbed energy production by mitochondria. The absence of α1AMPK also induced a reduction in histone deacetylase activity, which was associated with an increase in histone H3 acetylation (K9/K14 residues). Together, the results of the present study suggest that absence of AMPK, modifies oocyte quality through energy processes and oocyte/somatic cell communication. The limited effect observed in vivo could be partly due to a favourable follicle microenvironment where nutrients, growth factors, and adequate cell interaction were present. Whereas in a challenging environment such as that of in vitro culture following IVF, the phenotype is revealed.
Estradiol, progesterone, testosterone profiles in human follicular fluid and cultured granulosa cells from luteinized pre-ovulatory follicles
Background The production of sex steroids by follicular cells is proposed to be influenced by the maturity of the incumbent oocyte. Thus steroid levels may reflect suitability of an oocyte for IVF. We examined follicular fluids and granulosa cell production of steroid from IVF patients in order to test the relationship between steroid levels and fertilization. Methods Follicular fluid and granulosa cells were extracted from 206 follicles of 35 women undergoing controlled ovarian stimulation. Follicular fluid was assayed for estradiol, progesterone and testosterone. Granulosa cells were cultured from individual follicles and their culture media assayed for production of these hormones after 24 hrs in vitro. Levels of steroids were correlated with follicular diameter, oocyte recovery and subsequent fertilization. Results Follicular fluid levels of progesterone were 6100 times higher than that of estradiol, and 16,900 times higher that of testosterone. Despite the size of follicle triggered after controlled luteinisation, the levels of progesterone and testosterone were maintained at relatively constant levels (median 98.1 micromoles/L for progesterone, and 5.8 nanomoles/L for testosterone). However, estradiol levels were slightly lower in the larger follicles (follicular diameter 10-15 mm, median 25.3 nanomoles/L; follicles > = 15 mm, median 15.1 nanomoles/L; linear correlation r = -0.47, p < 0.0001). With respect to oocyte recovery, no steroid showed a significant association in follicular fluid levels. Similarly no difference in follicular fluid steroid levels was found for those oocytes that did or did not fertilize. Significant quantities of progesterone were produced by the granulosa cells but production was constant regardless of the size of follicle from which the cells originated. Estradiol levels were only detectable in 10 of 121 cultures examined, and testosterone in none. Interestingly, when an oocyte was present follicular estradiol levels correlated with progesterone levels. However, when absent, follicular estradiol levels correlated with testosterone levels but not with progesterone. Conclusions The principle steroid product of luteinized pre-ovulatory granulosa is progesterone, a differentiation triggered by the gonadotropin surge. However, absolute steroid levels are associated with follicular size, not oocyte maturation/ability to fertilize.
Follicular fluid hormonal profile and cumulus cell gene expression in controlled ovarian hyperstimulation with recombinant FSH: effects of recombinant LH administration
Purpose Down-regulation with gonadodropin-releasing agonist (GnRH-a) protocol during IVF stimulation leads to a severe endogenous LH suppression, which may affect the follicular development. The aim of the study was to evaluate the effects of recombinant LH (r-LH) administration, during late follicular development stages, in recombinant FSH (r-FSH) stimulated cycles on follicular fluid (FF) parameters and on cumulus cell quality. Methods Twenty patients undergoing IVF were stimulated in a long GnRH agonist protocol with r-FSH alone or with r-LH supplementation when the leading follicle reached diameter of 14 mm. FF was collected at the time of oocyte retrieval from 32 follicles ≥ 18 mm. Serum FSH, LH, estradiol (E 2 ), and progesterone (P 4 ) were evaluated on the day of hCG administration. Intra-follicular E 2 , P 4 , AMH and TGF-β were assayed. Total RNA from 18 individual cumuli was isolated for gene expression analyses. Results R-LH increased FF P 4 levels. FF TGF-β levels and PTGS2 and HAS2 expression in cumulus cells (CCs) positively correlated with increased P 4 levels observed in FFs, while a negative correlation was found between P 4 and AMH levels. Conclusions FF positive correlation between P 4 and TGF-β levels and CC expression of PTGS2 and HAS2 suggest an association with a better follicle quality. In addition, our data suggest that late follicular phase r-LH supplementation leads to a more advanced stage of follicular maturation.
Hippo signaling disruption and Akt stimulation of ovarian follicles for infertility treatment
Primary ovarian insufficiency (POI) and polycystic ovarian syndrome are ovarian diseases causing infertility. Although there is no effective treatment for POI, therapies for polycystic ovarian syndrome include ovarian wedge resection or laser drilling to induce follicle growth. Underlying mechanisms for these disruptive procedures are unclear. Here, we explored the role of the conserved Hippo signaling pathway that serves to maintain optimal size across organs and species. We found that fragmentation of murine ovaries promoted actin polymerization and disrupted ovarian Hippo signaling, leading to increased expression of downstream growth factors, promotion of follicle growth, and the generation of mature oocytes. In addition to elucidating mechanisms underlying follicle growth elicited by ovarian damage, we further demonstrated additive follicle growth when ovarian fragmentation was combined with Akt stimulator treatments. We then extended results to treatment of infertility in POI patients via disruption of Hippo signaling by fragmenting ovaries followed by Akt stimulator treatment and autografting. We successfully promoted follicle growth, retrieved mature oocytes, and performed in vitro fertilization. Following embryo transfer, a healthy baby was delivered. The ovarian fragmentation-in vitro activation approach is not only valuable for treating infertility of POI patients but could also be useful for middle-aged infertile women, cancer patients undergoing sterilizing treatments, and other conditions of diminished ovarian reserve.
The Roles of Luteinizing Hormone, Follicle-Stimulating Hormone and Testosterone in Spermatogenesis and Folliculogenesis Revisited
Spermatogenesis and folliculogenesis involve cell–cell interactions and gene expression orchestrated by luteinizing hormone (LH) and follicle-stimulating hormone (FSH). FSH regulates the proliferation and maturation of germ cells independently and in combination with LH. In humans, the requirement for high intratesticular testosterone (T) concentration in spermatogenesis remains both a dogma and an enigma, as it greatly exceeds the requirement for androgen receptor (AR) activation. Several data have challenged this dogma. Here we report our findings on a man with mutant LH beta subunit (LHβ) that markedly reduced T production to 1–2% of normal., but despite this minimal LH stimulation, T production by scarce mature Leydig cells was sufficient to initiate and maintain complete spermatogenesis. Also, in the LH receptor (LHR) knockout (LuRKO) mice, low-dose T supplementation was able to maintain spermatogenesis. In addition, in antiandrogen-treated LuRKO mice, devoid of T action, the transgenic expression of a constitutively activating follicle stimulating hormone receptor (FSHR) mutant was able to rescue spermatogenesis and fertility. Based on rodent models, it is believed that gonadotropin-dependent follicular growth begins at the antral stage, but models of FSHR inactivation in women contradict this claim. The complete loss of FSHR function results in the complete early blockage of folliculogenesis at the primary stage, with a high density of follicles of the prepubertal type. These results should prompt the reassessment of the role of gonadotropins in spermatogenesis, folliculogenesis and therapeutic applications in human hypogonadism and infertility.
Chemotherapy-induced damage to ovary: mechanisms and clinical impact
Cancer is a major public health problem around the world. Currently, about 5% of women diagnosed with cancer are of reproductive age. These young survivors may face compromised fertility. The effects of chemotherapeutic agents on ovarian reserve and its clinical consequences are generally inferred from a variety of surrogate markers of ovarian reserve, all aiming to provide prognostic information on fertility or the likelihood of success of infertility treatment. Until recently, the mechanisms that are responsible for chemotherapy-induced ovarian damage were not fully elucidated. The understanding of these mechanisms may lead to targeted treatments to preserve fertility. In this manuscript, we will review the current knowledge on the mechanism of ovarian damage and clinical impact of chemotherapy agents on fertility.
Autophagy in Ovarian Follicular Development and Atresia
Autophagy is a mechanism that exists in all eukaryotes under a variety of physiological and pathological conditions. In the mammalian ovaries, less than 1% of follicles ovulate, whereas the remaining 99% undergo follicular atresia. Autophagy and apoptosis have been previously found to be involved in the regulation of both primordial follicular development as well as atresia. The relationship between autophagy, follicular development, and atresia have been summarized in this review with the aim to obtain a more comprehensive understanding of the role played by autophagy in follicular development and atresia.