Long noncoding RNAs and mRNAs profiling in ovary during laying and broodiness in Taihe Black-Bone Silky Fowls (Gallus gallus Domesticus Brisson).

BACKGROUND: Broodiness significantly impacts poultry egg production, particularly notable in specific breeds such as the black-boned Silky, characterized by pronounced broodiness. An understanding of the alterations in ovarian signaling is essential for elucidating the mechanisms that influence broodiness. However, comparative research on the characteristics of long non-coding RNAs (lncRNAs) in the ovaries of broody chickens (BC) and high egg-laying chickens (GC) remains scant. In this investigation, we employed RNA sequencing to assess the ovarian transcriptomes, which include both lncRNAs and mRNAs, in eight Taihe Black-Bone Silky Fowls (TBsf), categorized into broody and high egg-laying groups. This study aims to provide a clearer understanding of the genetic underpinnings associated with broodiness and egg production. RESULTS: We have identified a total of 16,444 mRNAs and 18,756 lncRNAs, of which 349 mRNAs and 651 lncRNAs exhibited significantly different expression (DE) between the BC and GC groups. Furthermore, we have identified the cis-regulated and trans-regulated target genes of differentially abundant lncRNA transcripts and have constructed an lncRNA-mRNA trans-regulated interaction network linked to ovarian follicle development. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation analyses have revealed that DE mRNAs and the target genes of DE lncRNAs are associated with pathways including neuroactive ligand-receptor interaction, CCR6 chemokine receptor binding, G-protein coupled receptor binding, cytokine-cytokine receptor interaction, and ECM-receptor interaction. CONCLUSION: Our research presents a comprehensive compilation of lncRNAs and mRNAs linked to ovarian development. Additionally, it establishes a predictive interaction network involving differentially abundant lncRNAs and differentially expressed genes (DEGs) within TBsf. This significantly contributes to our understanding of the intricate interactions between lncRNAs and genes governing brooding behavior.

The recipient metabolome explains the asymmetric ovarian impact on fetal sex development after embryo transfer in cattle.

In cattle, lateral asymmetry affects ovarian function and embryonic sex, but the underlying molecular mechanisms remain unknown. The plasma metabolome of recipients serves to predict pregnancy after embryo transfer (ET). Thus, the aim of this study was to investigate whether the plasma metabolome exhibits distinct lateral patterns according to the sex of the fetus carried by the recipient and the active ovary side (AOS), i.e., the right ovary (RO) or the left ovary (LO). We analyzed the plasma of synchronized recipients by 1H+NMR on day 0 (estrus, n = 366) and day 7 (hours prior to ET; n = 367). Thereafter, a subset of samples from recipients that calved female (n = 50) or male (n = 69) was used to test the effects of embryonic sex and laterality on pregnancy establishment. Within the RO, the sex ratio of pregnancies carried was biased toward males. Significant differences (P < 0.05) in metabolite levels were evaluated based on the day of blood sample collection (days 0, 7 and day 7/day 0 ratio) using mixed generalized models for metabolite concentration. The most striking differences in metabolite concentrations were associated with the RO, both obtained by multivariate (OPLS-DA) and univariate (mixed generalized) analyses, mainly with metabolites measured on day 0. The metabolites consistently identified through the OPLS-DA with a higher variable importance in projection score, which allowed for discrimination between male fetus- and female fetus-carrying recipients, were hippuric acid, l-phenylalanine, and propionic acid. The concentrations of hydroxyisobutyric acid, propionic acid, l-lysine, methylhistidine, and hippuric acid were lowest when male fetuses were carried, in particular when the RO acted as AOS. No pathways were significantly regulated according to the AOS. In contrast, six pathways were found enriched for calf sex in the day 0 dataset, three for day 7, and nine for day 7/day 0 ratio. However, when the AOS was the right, 20 pathways were regulated on day 0, 8 on day 7, and 13 within the day 7/day 0 ratio, most of which were related to amino acid metabolism, with phenylalanine, tyrosine, and tryptophan biosynthesis and phenylalanine metabolism pathways being identified throughout. Our study shows that certain metabolites in the recipient plasma are influenced by the AOS and can predict the likelihood of carrying male or female embryos to term, suggesting that maternal metabolism prior to or at the time of ET could favor the implantation and/or development of either male or female embryos.

This study explored how the active ovary side (AOS, i.e., left or right) and the sex of the calf carried by the recipient relate to the plasma metabolome in blood. For this purpose, we analyzed blood samples from heifers at two specific times: the day of the estrus and the day of the embryo transfer. We found significant differences in the sex ratio of pregnancies carried in the right ovary, and in the levels of certain metabolites depending on whether the active ovary was on the right or left and whether the calf was male or female. As examples, the concentrations of hydroxyisobutyric acid, propionic acid, l-lysine, methylhistidine, and hippuric acid were lowest when male calves were carried, in particular when the right ovary was active. Interestingly, the calf sex also influenced certain metabolic pathways, especially in the right AOS, several of them related to amino acid metabolism. However, no significant metabolic pathway changes were observed based solely on which ovary was active. Overall, the study suggests that the metabolism of the recipient, influenced by the AOS, might play a role in the successful implantation and development of embryos of a certain sex. This insight could potentially help to predict and improve pregnancy outcomes in cattle through embryo transfer techniques.

Evaluating the therapeutic potential of moxibustion on polycystic ovary syndrome: a rat model study on gut microbiota and metabolite interaction.

Polycystic ovary syndrome (PCOS) is a common systemic disorder related to endocrine disorders, affecting the fertility of women of childbearing age. It is associated with glucose and lipid metabolism disorders, altered gut microbiota, and insulin resistance. Modern treatments like pioglitazone, metformin, and spironolactone target specific symptoms of PCOS, while in Chinese medicine, moxibustion is a common treatment. This study explores moxibustion's impact on PCOS by establishing a dehydroepiandrosterone (DHEA)-induced PCOS rat model. Thirty-six specific pathogen-free female Sprague-Dawley rats were divided into four groups: a normal control group (CTRL), a PCOS model group (PCOS), a moxibustion treatment group (MBT), and a metformin treatment group (MET). The MBT rats received moxibustion, and the MET rats underwent metformin gavage for two weeks. We evaluated ovarian tissue changes, serum testosterone, fasting blood glucose (FBG), and fasting insulin levels. Additionally, we calculated the insulin sensitivity index (ISI) and the homeostasis model assessment of insulin resistance index (HOMA-IR). We used 16S rDNA sequencing for assessing the gut microbiota, 1H NMR spectroscopy for evaluating metabolic changes, and Spearman correlation analysis for investigating the associations between metabolites and gut microbiota composition. The results indicate that moxibustion therapy significantly ameliorated ovarian dysfunction and insulin resistance in DHEA-induced PCOS rats. We observed marked differences in the composition of gut microbiota and the spectrum of fecal metabolic products between CTRL and PCOS rats. Intriguingly, following moxibustion intervention, these differences were largely diminished, demonstrating the regulatory effect of moxibustion on gut microbiota. Specifically, moxibustion altered the gut microbiota by increasing the abundance of UCG-005 and Turicibacter, as well as decreasing the abundance of Desulfovibrio. Concurrently, we also noted that moxibustion promoted an increase in levels of short-chain fatty acids (including acetate, propionate, and butyrate) associated with the gut microbiota of PCOS rats, further emphasizing its positive impact on gut microbes. Additionally, moxibustion also exhibited effects in lowering FBG, testosterone, and fasting insulin levels, which are key biochemical indicators associated with PCOS and insulin resistance. Therefore, these findings suggest that moxibustion could alleviate DHEA-induced PCOS by regulating metabolic levels, restoring balance in gut microbiota, and modulating interactions between gut microbiota and host metabolites.

Neurotensin modulates ovarian vascular permeability via adherens junctions.

Neurotensin (NTS) is a 13-amino acid peptide which is highly expressed in the mammalian ovary in response to the luteinizing hormone surge. Antibody neutralization of NTS in the ovulatory follicle of the cynomolgus macaque impairs ovulation and induces follicular vascular dysregulation, with excessive pooling of red blood cells in the follicle antrum. We hypothesize that NTS is an essential intrafollicular regulator of vascular permeability. In the present study, follicle injection of the NTS receptor antagonist SR142948 also resulted in vascular dysregulation. To measure vascular permeability changes in vitro, primary macaque ovarian microvascular endothelial cells (mOMECs) were enriched from follicle aspirates and studied in vitro. When treated with NTS, permeability of mOMECs decreased. RNA sequencing (RNA-Seq) of mOMECs revealed high mRNA expression of the permeability-regulating adherens junction proteins N-cadherin (CDH2) and K-cadherin (CDH6). Immunofluorescent detection of CDH2 and CDH6 confirmed expression and localized these cadherins to the cell-cell boundaries, consistent with function as components of adherens junctions. mOMECs did not express detectable levels of the typical vascular endothelial cadherin, VE-cadherin (CDH5) as determined by RNA-Seq, qPCR, western blot, and immunofluorescence. Knockdown of CDH2 or CDH6 via siRNA abrogated the NTS effect on mOMEC permeability. Collectively, these data suggest that NTS plays an ovulation-critical role in vascular permeability maintenance, and that CDH2 and CDH6 are involved in the permeability modulating effect of NTS on the ovarian microvasculature. NTS can be added to a growing number of angiogenic regulators which are critical for successful ovulation.

Spatiotemporal transcriptomic changes of human ovarian aging and the regulatory role of FOXP1.

Limited understanding exists regarding how aging impacts the cellular and molecular aspects of the human ovary. This study combines single-cell RNA sequencing and spatial transcriptomics to systematically characterize human ovarian aging. Spatiotemporal molecular signatures of the eight types of ovarian cells during aging are observed. An analysis of age-associated changes in gene expression reveals that DNA damage response may be a key biological pathway in oocyte aging. Three granulosa cells subtypes and five theca and stromal cells subtypes, as well as their spatiotemporal transcriptomics changes during aging, are identified. FOXP1 emerges as a regulator of ovarian aging, declining with age and inhibiting CDKN1A transcription. Silencing FOXP1 results in premature ovarian insufficiency in mice. These findings offer a comprehensive understanding of spatiotemporal variability in human ovarian aging, aiding the prioritization of potential diagnostic biomarkers and therapeutic strategies.

Real-Time Observation of Germinal Vesicle Migration During Oocyte Meiotic Cell Division Using Ovarian Fluorescent Transgenic Zebrafish.

The transgenic (TG) zebrafish allows researchers to bio-image specific biological phenomena in cells and tissues in vivo. We established TG lines to monitor changes in the ovaries of live fish. The original TG line with ovarian fluorescence was occasionally established. Although the cDNA integrated into the line was constructed for the expression of enhanced green fluorescent protein (EGFP) driven by the medaka ß-actin promoter, the expression of EGFP is restricted to the oocytes and gills in adult fish. Furthermore, we found that germinal vesicles (GVs) in oocytes of the established line can be observed by relatively strong fluorescence around the GV. In this study, we tried to capture the dynamic processes of germinal vesicle breakdown (GVBD) during meiotic cell division using the GV fluorescent oocytes. As a result, GV migration and GVBD could be monitored in real time. We also succeeded in observing actin filaments involved in the migration of GV to the animal pole. This strain can be used for education in the process of oocyte meiotic cell division.

[Mechanism of resveratrol in protecting ovary in poor ovarian response mice by regulating Hippo signaling pathway].

This study observed the protective effect of resveratrol(Res) on ovarian function in poor ovarian response(POR) mice by regulating the Hippo signaling pathway and explored the potential mechanism of Res in inhibiting ovarian cell apoptosis. Female mice with regular estrous cycles were randomly divided into a blank group, a model group, and low-and high-dose Res groups(20 and 40 mg·kg~(-1)), with 20 mice in each group. The blank group received an equal volume of 0.9% saline solution by gavage, while the model group and Res groups received suspension of glycosides of Triptergium wilfordii(GTW) at 50 mg·kg~(-1) by gavage for two weeks to induce the model. After modeling, the low-and high-dose Res groups were continuously treated with drugs by gavage for two weeks, while the blank group and the model group received an equal volume of 0.9% saline solution by gavage. Ovulation was induced in all groups on the day following the end of treatment. Finally, 12 female mice were randomly selected from each group, and the remaining eight female mice were co-housed with male mice at a ratio of 1∶1. Changes in the estrous cycle of mice were observed using vaginal cytology smears. The number of ovulated eggs, ovarian wet weight, ovarian index, and pregnancy rate of mice were measured. The le-vels of anti-Mullerian hormone(AMH), follicle-stimulating hormone(FSH), estradiol(E_2), and luteinizing hormone(LH) in serum were determined using enzyme-linked immunosorbent assay(ELISA). Ovarian tissue morphology and ovarian cell apoptosis were observed using hematoxylin-eosin(HE) staining and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL) staining, respectively. The protein expression levels of yes-associated protein(YAP) 1 and transcriptional coactivator with PDZ-binding motif(TAZ) were detected by immunohistochemistry(IHC), while the changes in protein expression levels of mammalian sterile 20-like kinase(MST) 1/2, large tumor suppressor(LATS) 1/2, YAP1, TAZ, B-cell lymphoma-2(Bcl-2), and Bcl-2 associated X protein(Bax) were determined by Western blot. The results showed that compared with the blank group, the model group had an increased rate of estrous cycle disruption in mice, a decreased number of normally developing ovarian follicles, an increased number of blocked ovarian follicles, increased ovarian granulosa cell apoptosis, decreased ovulation, reduced ovarian wet weight and ovarian index, increased serum FSH and LH levels, decreased AMH and E_2 levels, decreased protein expression levels of YAP1 and TAZ in ovarian tissues, increased relative expression levels of MST1/2, LATS1/2, and Bax proteins, and decreased relative expression levels of YAP1, TAZ, and Bcl-2 proteins. Additionally, the number of embryos per litter significantly decreased after co-housing. Compared with the model group, the low-and high-dose Res groups exhibited reduced estrous cycle disruption rates in mice, varying degrees of improvement in the number and morphology of ovarian follicles, reduced numbers of blocked ovarian follicles, improved ovarian granulosa cell apoptosis, increased ovulation, elevated ovarian wet weight and ovarian index, decreased serum FSH and LH levels, increased AMH and E_2 levels, elevated protein expression levels of YAP1 and TAZ in ovarian tissues, decreased relative expression levels of MST1/2, LATS1/2, and Bax proteins, and increased relative expression levels of YAP1, TAZ, and Bcl-2 proteins. Furthermore, the number of embryos per litter increased to varying degrees after co-housing. In conclusion, Res effectively inhibits ovarian cell apoptosis in mice and improves ovarian responsiveness. Its mechanism may be related to the regulation of key molecules in the Hippo pathway.

The relationship between oxidative stress and apoptosis of histopathological changes in the ovary made by mad honey containing grayanotoxin.

The purpose of this study is to determine the effects of grayanotoxin in mad honey on ovarian tissue folliculogenesis in terms of cell death and nitric oxide expression. Three groups of 18 female Sprague-Dawley rats were formed. The first group received mad honey (80 mg/kg), the second group received normal honey (80 mg/kg), and the third group was the control. The first and second groups received normal and mad honey by oral gavage for 30 days before being sacrificed under anesthesia. Caspase 3 immunostaining showed a moderate to strong response, particularly in the mad honey group. In the mad honey group, immunostaining for caspase 8 and caspase 9 revealed a moderate immunoreaction in the granulosa cells of the Graaf follicles. The majority of Graaf follicles exhibited TUNEL positive in the mad honey group. The iNOS immunoreaction revealed a high level of expression in the mad honey group. In all three groups, eNOS immunostaining showed weak reactivity. According to the findings of apoptotic and nitric oxide marker expression, it was determined that mad honey may result in an increase in follicular atresia in ovarian follicles when compared to normal honey and control groups.

Chronic exposure to gestodene impairs reproductive system in adult female zebrafish (Daniarerio).

Gestodene (GES) is widely used in human therapy and animal husbandry and is frequently detected in aquatic environments. Although GES adversely affects aquatic organisms at trace levels, its effects on the reproductive biology of fish remain inconclusive. In this study, female zebrafish (Danio rerio) were exposed to environmentally relevant levels of GES for the evaluation of the effects of GES on the reproductive system by using endpoints including gene expression, plasma steroid concentrations, histological and morphological analyses, copulatory behavior, and reproductive output. Adult female zebrafish exposed to environmentally relevant concentrations of GES (4.0, 40.2, and 372.7 ng/L) for 60 d demonstrated stagnant ovarian oocyte development, evidenced by an increase in the percentage of perinuclear and atretic oocytes and a decrease in the percentage of late vitellogenic oocytes. GES-exposed females were less attractive to males and had lower copulatory intimacy than females in control. Consequently, spawning (44.3-49.2 %) and egg fertilization rates (27.9-32.0 %) were decreased. The decreased survival of fertilized eggs and hatching rates were accompanied by increased malformations. These negative effects were associated with abnormal transcriptional levels of gonadal steroid hormones, which were regulated by genes (Hsd17ß3, Hsd11ß2, Hsd20ß, Cyp19a1a, and Cyp11b). Overall, our findings suggest that GES impairs the reproductive system of zebrafish, which may threaten population stability.

A prospective cohort study with serum anti-mullerian hormone levels change in patients undergoing uterine preservation after gestational trophoblastic neoplasia treatment with a methotrexate regimen.

Objectives: To monitor changes in serum anti-Mullerian hormone (AMH) levels of the patients with gestational trophoblastic neoplasia (GTN) who have undergone uterine preservation during treatment with a Methotrexate (MTX) regimen and associations with AMH variations. Methods: This observational prospective cohort study included 35 patients with low-risk GTN with uterine preservation during single-agent MTX chemotherapy at Hanoi Obstetrics and Gynecology Hospital from August 2021 to August 2022. Serum AMH levels were measured before initiation of chemotherapy and after the 1st, 2nd, and 3rd chemotherapy cycles. AMH evolution and its associations with some factors were analyzed. Results: The median basal AMH level before chemotherapy was 2.87 ng/mL (0.96 - 7.9 ng/mL) and negatively correlated with age. The serum AMH levels decreased significantly after each chemotherapy cycle (2.87 vs. 1.16, 0.91, 0.41 ng/mL). The median magnitude of the AMH levels decline after 1st, 2nd, and 3rd chemotherapy cycles were 51.2%, 69.4%, and 84.6% (p<0.001), respectively. AMH variation was associated with the basal AMH level, but not with age, ßhCG at diagnosis and menstrual status. Conclusion: Our study has shown that the serum AMH levels declined rapidly and steadily in all patients during chemotherapy for GTN. Although AMH cannot be used to monitor fertility potential lonely, these new studies improve our knowledge of ovarian toxicity and ovarian reserve during chemotherapy and strongly support the use of fertility preservation strategies.

Efficacy and safety of mesenchymal stem cell therapy for ovarian ageing in a mouse model.

BACKGROUND: Ovarian ageing is one of the major issues that impacts female fertility. Mesenchymal stem cell (MSC)-based therapy has made impressive progress in recent years. However, the efficacy and safety of MSCs, as nonautologous components, remain to be further verified. METHODS: Two common sources of MSCs, umbilical cord-derived MSCs (UC-MSCs) and adipose tissue-derived MSCs (AD-MSCs), were orthotopically transplanted into a mouse model of ovarian ageing to evaluate their therapeutic effects. The safety of the treatment was further evaluated, and RNA sequencing was performed to explore the underlying mechanisms involved. RESULTS: After orthotopic transplantation of MSCs into the ovary, the oestrous cycle, ovarian weight, number and proportion of primary follicles, granulosa cell proliferation, and angiogenesis were improved. The effects of AD-MSCs were superior to those of UC-MSCs in several indices, such as post-transplant granulosa cell proliferation, ovarian weight and angiogenesis. Moreover, the tumorigenesis, acute toxicity, immunogenicity and biodistribution of MSCs were evaluated, and both AD-MSCs and UC-MSCs were found to possess high safety profiles. Through RNA sequencing analysis, enhancement of the MAPK cascade was observed, and long-term effects were mainly linked to the activation of immune function. CONCLUSIONS: Orthotopic transplantation of MSCs displays significant efficacy and high safety for the treatment of ovarian ageing in mice.

The adipokines progranulin and omentin - novel regulators of basic ovarian cell functions.

The present study aimed to examine the effects of progranulin and omentin on basic ovarian cell functions. For this purpose, we investigated the effects of the addition of progranulin and omentin (0, 0.1, 1, or 10 ng/ml) on the viability, proliferation, apoptosis and steroidogenesis of cultured rabbit ovarian granulosa cells. To determine the importance of the interrelationships between granulosa cells and theca cells, we compared the influence of progranulin and omentin on progesterone and estradiol release in cultured granulosa cells and ovarian fragments containing both granulosa cells and theca cells. Cell viability, proliferation, cytoplasmic apoptosis and release of progesterone and estradiol were measured by Cell Counting Kit-8 (CCK-8), BrdU incorporation, cell death detection, and ELISA. Both progranulin and omentin increased granulosa cell viability and proliferation and decreased apoptosis. Progranulin increased progesterone release by granulosa cells but reduced progesterone output by ovarian fragments. Progranulin decreased estradiol release by granulosa cells but increased it in ovarian fragments. Omentin reduced progesterone release in both models. Omentin reduced estradiol release by granulosa cells but promoted this release in ovarian fragments. The present observations are the first to demonstrate that progranulin and omentin can be direct regulators of basic ovarian cell functions. Furthermore, the differences in the effects of these adipokines on steroidogenesis via granulosa and ovarian fragments indicate that these peptides could target both granulosa and theca cells.

Transcriptome analysis during 4-vinylcyclohexene diepoxide exposure-induced premature ovarian insufficiency in mice.

The occupational chemical 4-Vinylcyclohexene diepoxide (VCD) is a reproductively toxic environmental pollutant that causes follicular failure, leading to premature ovarian insufficiency (POI), which significantly impacts a woman's physical health and fertility. Investigating VCD's pathogenic mechanisms can offer insights for the prevention of ovarian impairment and the treatment of POI. This study established a mouse model of POI through intraperitoneal injection of VCD into female C57BL/6 mice for 15 days. The results were then compared with those of the control group, including a comparison of phenotypic characteristics and transcriptome differences, at two time points: day 15 and day 30. Through a comprehensive analysis of differentially expressed genes (DEGs), key genes were identified and validated some using RT-PCR. The results revealed significant impacts on sex hormone levels, follicle number, and the estrous cycle in VCD-induced POI mice on both day 15 and day 30. The DEGs and enrichment results obtained on day 15 were not as significant as those obtained on day 30. The results of this study provide a preliminary indication that steroid hormone synthesis, DNA damage repair, and impaired oocyte mitosis are pivotal in VCD-mediated ovarian dysfunction. This dysfunction may have been caused by VCD damage to the primordial follicular pool, impairing follicular development and aggravating ovarian damage over time, making it gradually difficult for the ovaries to perform their normal functions.

Reproductive and transgenerational toxicity of bisphenol S exposure in pregnant rats: Insights into hormonal imbalance and steroid biosynthesis pathway disruption.

Bisphenol S (BPS) is an alternative chemical to bisphenol A commonly used in food packaging materials. It raises concerns due to potential adverse effects on human health. However, limited evidence exists regarding reproductive toxicity from BPS exposure, and the mechanism of associated transgenerational toxicity remains unclear. In this study, pregnant SD rats were exposed to two different doses of BPS (0.05 or 20 mg/kg) from GD6 to PND21. The objective was to investigate reproductive and transmissible toxicity induced by BPS, explore endocrine effects, and uncover potential underlying mechanisms in rats. Perinatal exposure to BPS in the F0 generation significantly decreased the rate of body weight, ovarian organ coefficient, and growth and development of the F1 generation. Notably, these changes included abnormal increases in body weight and length, estrous cycle disruption, and embryonic dysplasia in F1. 4D-DIA proteomic and PRM analyses revealed that exposure to 20 mg/kg group significantly altered the expression of proteins, such as Lhcgr and Akr1c3, within the steroid biosynthetic pathway. This led to elevated levels of FSH and LH in the blood. The hypothalamic-pituitary-ovarian (HPO) axis, responsible for promoting fertility through the cyclic secretion of gonadotropins and steroid hormones, was affected. RT-qPCR and Western blot results demonstrated that the expression of GnRH in the hypothalamus was decreased, the GnRHR in the pituitary gland was decreased, and the expression of FSHß and LHß in the pituitary gland was increased. Overall, BPS exposure disrupts the HPO axis, hormone levels, and steroid biosynthesis in the ovaries, affecting offspring development and fertility. This study provides new insights into the potential effects of BPS exposure on the reproductive function of the body and its relevant mechanisms of action.

Bulk and single-cell transcriptome datasets of the mouse fetal and adult rete ovarii and surrounding tissues.

The rete ovarii (RO) is an epithelial structure that arises during development in close proximity to the ovary and persists throughout adulthood. However, the functional significance of the RO remains elusive, and it is absent from recent discussions of female reproductive anatomy. The RO comprises three regions: the intraovarian rete within the ovary, the extraovarian rete in the periovarian tissue, and the connecting rete linking the two. We hypothesize that the RO plays a pivotal role in ovarian homeostasis and responses to physiological changes. To begin to uncover the nature and function of RO cells, we conducted transcriptomic profiling of the RO. This study presents three datasets, and reports our analysis and quality control approaches for bulk, single-cell, and nucleus-level transcriptomics of the fetal and adult RO tissues using the Pax8-rtTA; Tre-H2B-GFP mouse line, where all RO regions express nuclear GFP. The integration and rigorous validation of these datasets will advance our understanding of the RO's roles in ovarian development, female maturation, and adult female fertility.

ERß Regulation of Indian Hedgehog Expression in the First Wave of Ovarian Follicles.

Increased activation of ovarian primordial follicles in Erß knockout (ErßKO) rats becomes evident as early as postnatal day 8.5. To identify the ERß-regulated genes that may control ovarian primordial follicle activation, we analyzed the transcriptome profiles of ErßKO rat ovaries collected on postnatal days 4.5, 6.5, and 8.5. Compared to wildtype ovaries, ErßKO ovaries displayed dramatic downregulation of Indian hedgehog (Ihh) expression. IHH-regulated genes, including Hhip, Gli1, and Ptch1, were also downregulated in ErßKO ovaries. This was associated with a downregulation of steroidogenic enzymes Cyp11a1, Cyp19a1, and Hsd17b1. The expression of Ihh remained very low in ErßKO ovaries despite the high levels of Gdf9 and Bmp15, which are known upregulators of Ihh expression in the granulosa cells of activated ovarian follicles. Strikingly, the downregulation of the Ihh gene in ErßKO ovaries began to disappear on postnatal day 16.5 and recovered on postnatal day 21.5. In rat ovaries, the first wave of primordial follicles is rapidly activated after their formation, whereas the second wave of primordial follicles remains dormant in the ovarian cortex and slowly starts activating after postnatal day 12.5. We localized the expression of Ihh mRNA in postnatal day 8.5 wildtype rat ovaries but not in the age-matched ErßKO ovaries. In postnatal day 21.5 ErßKO rat ovaries, we detected Ihh mRNA mainly in the activated follicles in the ovaries' peripheral regions. Our findings indicate that the expression of Ihh in the granulosa cells of the activated first wave of ovarian follicles depends on ERß.

EPAS1 expression contributes to maintenance of the primordial follicle pool in the mouse ovary.

Oxygen availability can have profound effects on cell fate decisions and survival, in part by regulating expression of hypoxia-inducible factors (HIFs). In the ovary, HIF expression has been characterised in granulosa cells, however, any requirement in oocytes remains relatively undefined. Here we developed a Hif2a/Epas1 germline-specific knockout mouse line in which females were fertile, however produced 40% fewer pups than controls. No defects in follicle development were detected, and quality of MII oocytes was normal, as per assessments of viability, intracellular reactive oxygen species, and spindle parameters. However, a significant diminishment of the primordial follicle pool was evident in cKO females that was attributed to accelerated follicle loss from postnatal day 6 onwards, potentially via disruption of the autophagy pathway. These data demonstrate the importance of HIF signalling in oocytes, particularly at the primordial follicle stage, and lend to the importance of controlling oxygen tension in the development of in vitro growth and maturation approaches for assisted reproduction.

Poor ovarian response classification systems in the clinical setting - time for an update?

PURPOSE OF REVIEW: Poor ovarian response (POR) remains a key challenge to the success of assisted reproductive technology. Here, we offer a comprehensive review of the two main classification systems for POR, discussing their promises and pitfalls, evaluating their performance, and exploring potential avenues for improving upon these definitions of POR. RECENT FINDINGS: The Bologna criteria represented the first meaningful attempt to create a universal POR definition. Subsequently, the POSEIDON classification system was published to provide a more nuanced view of POR, classifying patients into four groups based on age and ovarian reserve markers. A recent study evaluated the likelihood of achieving at least one euploid embryo for transfer and found that, indeed, these classification systems are effective predictors of this outcome.While these criteria provide an effective counseling tool, several limitations - not considering underlying conditions, selecting somewhat arbitrary cutoffs, and evaluating the number of oocytes retrieved regardless of maturity - highlight the importance of improving upon these systems to create a more useful tool to more accurately predict ovarian response for clinical and research purposes. SUMMARY: In the era of personalized medicine, it is time to reconsider whether diagnostic criteria for a continuous metric such as ovarian response should be based on meeting all-or-nothing thresholds for specific parameters.

Diversity of Androgens; Comparison of Their Significance and Characteristics in Vertebrate Species.

Androgen(s) is one of the sex steroids that are involved in many physiological phenomena of vertebrate species. Although androgens were originally identified as male sex hormones, it is well known now that they are also essential in females. As in the case of other steroid hormones, androgen is produced from cholesterol through serial enzymatic reactions. Although testis is a major tissue to produce androgens in all species, androgens are also produced in ovary and adrenal (interrenal tissue). Testosterone is the most common and famous androgen. It represents a major androgen both in males and females of almost vertebrate species. In addition, testosterone is a precursor for producing significant androgens such as11-ketotestosterone, 5α-dihydrotestosterone, 11-ketodihydrotestosterones and 15α-hydroxytestosterone in a species- or sex-dependent manner for their homeostasis. In this article, we will review the significance and characteristics of these androgens, following a description of the history of testosterone discovery and its synthetic pathways.