Normal Ovarian Development Research Articles

Long non-coding RNA NEAT1 promotes ovarian granulosa cell proliferation and cell cycle progression via the miR-29a-3p/IGF1 axis

BackgroundGranulosa cell proliferation and survival are essential for normal ovarian function and follicular development. Long non-coding RNAs (lncRNAs) have emerged as important regulators of cell proliferation and differentiation. Nuclear paraspeckle assembly transcript 1 (NEAT1) has been implicated in various cellular processes, but its role in granulosa cell function remains unclear.MethodsWe investigated the function of lncRNA NEAT1 in human ovarian granulosa-like tumor cells (KGN). The effects of NEAT1 overexpression or silencing on cell proliferation and cell cycle were evaluated using CCK-8 assays and flow cytometry. The interaction between NEAT1, miR-29a-3p, and IGF1 was examined using dual-luciferase reporter assays, qRT-PCR, and Western blot analysis.ResultsNEAT1 promoted granulosa cell proliferation and cell cycle progression by indirectly upregulated IGF1 expression through acting as a molecular sponge for miR-29a-3p. Cell proliferation and G2/M phase proportions were increased by overexpression of NEAT1, whereas cell proliferation and G2/M phase proportions decreased with NEAT1 silencing. The effects of NEAT1 on cell proliferation and cell cycle-related proteins (CCNB1 and CDK2) were partially reversed by miR-29a-3p mimic, while miR-29a-3p inhibitor rescued the effects of NEAT1 silencing.ConclusionLncRNA NEAT1 could promote ovarian granulosa cell proliferation and cell cycle progression via the miR-29a-3p/IGF1 axis in polycystic ovary syndrome. Further investigation of this mechanism in clinical samples may have implications for understanding ovarian physiology and pathology.

Transcriptome and metabolome revealed the effects of hypoxic environment on ovarian development of Tibetan sheep

Many studies on the adaptability of Tibetan sheep to hypoxia have been reported, but little attention has been paid to the reproduction of Tibetan sheep living at an altitude of more than 4000 m. In this study, the ovaries of Alpine Merino sheep (AM) living in middle-high altitude areas (2500 m) and the ovaries of Gangba Tibetan sheep (GB) and Huoba Tibetan sheep (HB) living in ultra-high altitude areas (4400 m or more) were collected. Through morphological, transcriptomics and metabolomics, the effects of ultra-high altitude areas on Tibetan sheep ovarian development and the molecular mechanism of sheep's adaptability to ultra-high altitude environment were explored. The results showed that the number of granulosa cells in AM was significantly higher than that in GB and HB. The transcriptome revealed several genes related to follicular development, such as DAPL1, IGFBP1, C5, GPR12, STRA6, BMPER, etc., which were mainly enriched in related pathways such as cell growth and development. Through metabolomics analysis, it was found that the differential metabolites between the three groups of sheep were mainly lipids and lipid-like small molecules, such as Glycerol 3-Phosphate, PC (16: 0 / 18: 3 (9Z, 12Z, 15Z)), mainly enriched in lipid metabolism and other related pathways. The results of combined analysis showed that Tryptophan metabolism and Steroid hormone biosynthesis may have a significant effect on Tibetan sheep follicular development. Some genes (including HSD17B7, CYP11A1, CYP19, HSD3B1, CYP17, etc.) and some metabolites (including Cortisone, 2-Methoxyestrone, etc.) are enriched in these pathways, regulating ovarian and follicular development by affecting estrogen, progesterone, etc.. The results further revealed the molecular mechanism of Tibetan sheep to adapt to the ultra-high altitude environment and maintain normal ovarian and follicular development through the regulation of genes and metabolites.

Diagnosis and management of non-CAH 46,XX disorders/differences in sex development.

Prenatal-onset androgen excess leads to abnormal sexual development in 46,XX individuals. This androgen excess can be caused endogenously by the adrenals or gonads or by exposure to exogenous androgens. The most common cause of 46,XX disorders/differences in sex development (DSD) is congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, comprising >90% of 46,XX DSD cases. Deficiencies of 11β-hydroxylase, 3β-hydroxysteroid dehydrogenase, and P450-oxidoreductase (POR) are rare types of CAH, resulting in 46,XX DSD. In all CAH forms, patients have normal ovarian development. The molecular genetic causes of 46,XX DSD, besides CAH, are uncommon. These etiologies include primary glucocorticoid resistance (PGCR) and aromatase deficiency with normal ovarian development. Additionally, 46,XX gonads can differentiate into testes, causing 46,XX testicular (T) DSD or a coexistence of ovarian and testicular tissue, defined as 46,XX ovotesticular (OT)-DSD. PGCR is caused by inactivating variants in NR3C1, resulting in glucocorticoid insensitivity and the signs of mineralocorticoid and androgen excess. Pathogenic variants in the CYP19A1 gene lead to aromatase deficiency, causing androgen excess. Many genes are involved in the mechanisms of gonadal development, and genes associated with 46,XX T/OT-DSD include translocations of the SRY; copy number variants in NR2F2, NR0B1, SOX3, SOX9, SOX10, and FGF9, and sequence variants in NR5A1, NR2F2, RSPO1, SOX9, WNT2B, WNT4, and WT1. Progress in cytogenetic and molecular genetic techniques has significantly improved our understanding of the etiology of non-CAH 46,XX DSD. Nonetheless, uncertainties about gonadal function and gender outcomes may make the management of these conditions challenging. This review explores the intricate landscape of diagnosing and managing these conditions, shedding light on the unique aspects that distinguish them from other types of DSD.

Hyperandrogenic environment regulates the function of ovarian granulosa cells by modulating macrophage polarization in PCOS.

Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder characterized by oligo-anovulation, hyperandrogenism, and polycystic ovaries, with hyperandrogenism being the most prominent feature of PCOS patients. However, whether excessive androgens also exist in the ovarian microenvironment of patients with PCOS, and their modulatory role on ovarian immune homeostasis and ovarian function, is not clear. Follicular fluid samples from patients participating in their first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment were collected. Androgen concentration of follicular fluid was assayed by chemiluminescence, and the macrophage M1:M2 ratio was detected by flow cytometry. In an in vitro model, we examined the regulatory effects of different concentrations of androgen on macrophage differentiation and glucose metabolism levels using qRT-PCR, Simple Western and multi-factor flow cytometry assay. In a co-culture model, we assessed the effect of a hyperandrogenic environment in the presence or absence of macrophages on the function of granulosacells using qRT-PCR, Simple Western, EdU assay, cell cycle assay, and multi-factor flow cytometry assay. The results showed that a significantly higher androgen level and M1:M2 ratio in the follicular fluid of PCOS patients with hyperandrogenism. The hyperandrogenic environment promoted the expression of pro-inflammatory and glycolysis-related molecules and inhibited the expression of anti-inflammatory and oxidative phosphorylation-related molecules in macrophages. In the presence of macrophages, a hyperandrogenic environment significantly downregulated the function of granulosa cells. There is a hyperandrogenic microenvironment in the ovary of PCOS patients with hyperandrogenism. Hyperandrogenic microenvironment can promote the activation of ovarian macrophages to M1, which may be associated with the reprogramming of macrophage glucose metabolism. The increased secretion of pro-inflammatory cytokines by macrophages in the hyperandrogenic microenvironment would impair the normal function of granulosa cells and interfere with normal ovarian follicle growth and development.

Disruption of Thyroid Hormone Receptor Thrab Leads to Female Infertility in Zebrafish.

Thyroid hormones (THs) T4 and T3 are vital for development, growth, and metabolism. Thyroid dysfunction can also cause problems in fertility, suggesting involvement of THs in reproduction. In zebrafish, there exist 2 forms of TH receptor alpha gene (thraa and thrab). Disruption of these genes by CRISPR/Cas9 showed no reproductive irregularities in the thraa mutant; however, inactivation of the thrab gene resulted in female infertility. Although young female mutants (thrabm/m) showed normal ovarian development and folliculogenesis before sexual maturation, they failed to release eggs during oviposition after sexual maturation. This spawning failure was due to oviductal blockage at the genital papilla. The obstruction of the oviduct subsequently caused an accumulation of the eggs in the ovary, resulting in severe ovarian hypertrophy, abdominal distention, and disruption of folliculogenesis. Gene expression analysis showed expression of both TH receptors and estrogen receptors in the genital papilla, suggesting a direct TH action and potential interactions between thyroid and estrogen signaling pathways in controlling genital papilla development and function. In addition to their actions in the reproductive tracts, THs may also have direct effects in the ovary, as suggested by follicle atresia and cessation of folliculogenesis in the heterozygous mutant (thrab+/m), which was normal in all aspects of female reproduction in young and sexually mature fish but exhibited premature ovarian failure in aged females. In summary, this study provides substantial evidence for roles of THs in controlling the development and functions of both reproductive tract and ovary.

A spatiotemporal gene expression and cell atlases of the developing rat ovary.

Normal ovarian development is necessary for the production of healthy oocytes. However, the characteristics of oocytes development at different stages and the regulatory relationship between oocytes and somatic cells remain to be fully explained. Here, we combined scRNA-seq and spatial transcriptomic sequencing to profile the transcriptomic atlas of developing ovarian of the rat. We identified four components from developing granulosa cells including cumulus, primitive, mural, and luteal cells, and constructed their differential transcriptional regulatory networks. Several novel growth signals from oocytes to cumulus cells were identified, such as JAG1-NOTCH2 and FGF9-FGFR2. Moreover, we observed three cumulus sequential phases during follicle development determined by the key transcriptional factors in each cumulus phase (Bckaf1, Gata6, Cebpb, etc.), as well as the potential pinpointed roles of macrophages in luteal regression. Altogether, the single-cell spatial transcriptomic profile of the ovary provides not only a new research dimension for temporal and spatial analysis of ovary development, but also valuable data resources and a research basis for in-depth excavation of the mechanisms of mammalian ovary development.

Squeezing the eggs to grow: The mechanobiology of mammalian folliculogenesis.

The formation of functional eggs (oocyte) in ovarian follicles is arguably one of the most important events in early mammalian development since the oocytes provide the bulk genetic and cytoplasmic materials for successful reproduction. While past studies have identified many genes that are critical to normal ovarian development and function, recent studies have highlighted the role of mechanical force in shaping folliculogenesis. In this review, we discuss the underlying mechanobiological principles and the force-generating cellular structures and extracellular matrix that control the various stages of follicle development. We also highlight emerging techniques that allow for the quantification of mechanical interactions and follicular dynamics during development, and propose new directions for future studies in the field. We hope this review will provide a timely and useful framework for future understanding of mechano-signalling pathways in reproductive biology and diseases.

Development of the human ovary: Fetal through pubertal ovarian morphology, folliculogenesis and expression of cellular differentiation markers

A definition of normal human fetal and early postnatal ovarian development is critical to the ability to accurately diagnose the presence or absence of functional ovarian tissue in clinical specimens. Through assembling an extensive histologic and immunohistochemical developmental ontogeny of human ovarian specimens from 8 weeks of gestation through 16 years of postnatal, we present a comprehensive immunohistochemical mapping of normal protein expression patterns in the early fetal through post-pubertal human ovary and detail a specific expression-based definition of the early stages of follicular development. Normal fetal and postnatal ovarian tissue is defined by the presence of follicular structures and characteristic immunohistochemical staining patterns, including granulosa cells expressing Forkhead Box Protein L2 (FOXL2). However, the current standard array of immunohistochemical markers poorly defines ovarian stromal tissue, and additional work is needed to identify new markers to advance our ability to accurately identify ovarian stromal components in gonadal specimens from patients with disorders of sexual differentiation.

P-603 Presence of an asymmetrical response to ovarian stimulation in patients with low ovarian reserve

Abstract Study question Does ovarian reserve decline with a symmetrical manner between right and left ovaries in poor responders (POR) with diminished ovarian reserve (DOR)? Summary answer Asymmetrical ovarian response to ovarian stimulation with the left-side dominance was found in POR with DOR. What is known already Ovarian follicles are produced during fetal stage and not regenerated after birth. Thus, the number of ovarian follicles declines with age, resulting in infertile POR with DOR. In the morphometric study of human neonatal ovaries, no significant difference was found in the number of follicles between the right and left ovaries in the same individual. A previous study demonstrated that there is a difference in the number of follicles between right and left ovaries in patients with normal ovarian reserve with the right-side dominance, suggesting the asymmetrical activation and growth of follicles. Study design, size, duration A retrospective analysis was conducted in patients with POR with DOR based on the Bologna Criteria. Inclusion criteria was patients who received more than five times of ovarian stimulations followed by oocyte retrievals. Data were obtained from a total of 265 participants who received IVF-ET treatments from April 2015 to March 2021 after receiving written informed consents under an approval from the institutional ethical committee. Patients with the history of previous ovarian surgery were excluded. Participants/materials, setting, methods The enrolled patients were received ovarian simulation under short or GnRH antagonist protocols for oocyte retrieval. We collected the data of retrieved oocyte number as well as the outcome of IVF from medical chart. We defined the right-left asymmetry of ovarian reserve (%) based on the number of retrieved oocytes from dominant side ovary per total number of retrieved oocytes. Statistical significance was determined using Dunnett or chi-square tests, with P < 0.05 being statistically significant. Main results and the role of chance The average age of participants was 37.2±5.99 years of age exhibiting low serum AMH levels (average 0.09±0.20 ng/ml). We analyzed 2,181 cycles of ovarian stimulation (average 8.3±3.9 cycles/patient). The number of retrieved oocytes were 3, 882 in total cycles (average 12.8±7.1/patient). Among participants, 22 cases (8.4%) showed left and right equal in the number of retrieved oocytes, whereas >70% asymmetry was observed in 107 cases (40.7%) and >80% asymmetry was detected in 60 cases (22.8%). In 18 cases (6.9%), oocytes were collected from one side ovary only showing 100% asymmetry. In the cases with >70 and 100% asymmetry, the left-side dominance was 1.3-fold and 5.0-fold higher than right-side dominance, respectively. In cases with 100% asymmetry, there was no difference in the number of cryopreserved high-quality embryos between left and right sides of ovary. Limitations, reasons for caution Although we enrolled POR with DOR patients who received ovarian stimulations more than five times, the duration of ovarian stimulation was different among patients. It affects the numbers of ovarian stimulation cycles and retrieved oocytes in each patient. Wider implications of the findings Considering the finding of right-side dominance in the number of follicles with normal ovarian reserve, the activation and development of follicles might be accelerated in the right side due to asymmetric blood supply to the ovaries, and thus follicles are likely remained in the left-side ovary with low ovarian reserve. Trial registration number not applicable

FMRP-dependent production of large dosage-sensitive proteins is highly conserved.

Mutations in FMR1 are the most common heritable cause of autism spectrum disorder. FMR1 encodes an RNA-binding protein, FMRP, which binds to long, autism-relevant transcripts and is essential for normal neuronal and ovarian development. In contrast to the prevailing model that FMRP acts to block translation elongation, we previously found that FMRP activates the translation initiation of large proteins in Drosophila oocytes. We now provide evidence that FMRP-dependent translation is conserved and occurs in the mammalian brain. Our comparisons of the mammalian cortex and Drosophila oocyte ribosome profiling data show that translation of FMRP-bound mRNAs decreases to a similar magnitude in FMRP-deficient tissues from both species. The steady-state levels of several FMRP targets were reduced in the Fmr1 KO mouse cortex, including a ∼50% reduction of Auts2, a gene implicated in an autosomal dominant autism spectrum disorder. To distinguish between effects on elongation and initiation, we used a novel metric to detect the rate-limiting ribosome stalling. We found no evidence that FMRP target protein production is governed by translation elongation rates. FMRP translational activation of large proteins may be critical for normal human development, as more than 20 FMRP targets including Auts2 are dosage sensitive and are associated with neurodevelopmental disorders caused by haploinsufficiency.

Integrated stress response control of granulosa cell translation and proliferation during normal ovarian follicle development.

Mechanisms that directly control mammalian ovarian primordial follicle (PF) growth activation and the selection of individual follicles for survival are largely unknown. Follicle cells produce factors that can act as potent inducers of cellular stress during normal function. Consistent with this, we show here that normal, untreated ovarian cells, including pre-granulosa cells of dormant PFs, express phenotype and protein markers of the activated integrated stress response (ISR), including stress-specific protein translation (phospho-Serine 51 eukaryotic initiation factor 2α; P-EIF2α), active DNA damage checkpoints, and cell-cycle arrest. We further demonstrate that mRNAs upregulated in primary (growing) follicles versus arrested PFs mostly include stress-responsive upstream open reading frames (uORFs). Treatment of a granulosa cell (GC) line with the PF growth trigger tumor necrosis factor alpha results in the upregulation of a 'stress-dependent' translation profile. This includes further elevated P-eIF2α and a shift of uORF-containing mRNAs to polysomes. Because the active ISR corresponds to slow follicle growth and PF arrest, we propose that repair and abrogation of ISR checkpoints (e.g. checkpoint recovery) drives the GC cell cycle and PF growth activation (PFGA). If cellular stress is elevated beyond a threshold(s) or, if damage occurs that cannot be repaired, cell and follicle death ensue, consistent with physiological atresia. These data suggest an intrinsic quality control mechanism for immature and growing follicles, where PFGA and subsequent follicle growth and survival depend causally upon ISR resolution, including DNA repair and thus the proof of genomic integrity.

RNA interference of Argonaute-1 delays ovarian development in the oriental fruit fly, Bactrocera dorsalis (Hendel).

With the development of rapid resistance, new modes of action for pesticides are needed for insect control, such as RNAi-based biopesticides targeting essential genes. To explore the function of Argonaute-1 (Ago-1) and potential miRNAs in ovarian development of Bactrocera dorsalis, an important agricultural pest, and to develop a novel control strategy for the pest, BdAgo-1 was first identified in B. dorsalis. Spatiotemporal expression analysis indicated that BdAgo-1 had a relatively high transcriptional level in the ovarian tissues of adult female B. dorsalis during the sexual maturation period. RNA interference (RNAi) experiment showed that BdAgo-1 knockdown significantly decreased the expression levels of ovarian development-related genes and delayed ovarian development. Although RNAi-mediated silencing of Ago-1 led to a reduced ovary surface area, a subsequent oviposition assay revealed that the influence was minimal over a longer time period. Small RNA libraries were constructed and sequenced from different ovarian developmental stages of B. dorsalis adults. Among 161 identified miRNAs, 84 miRNAs were differentially expressed during the three developmental stages of the B. dorsalis ovary. BdAgo-1 silencing caused significant down-regulation of seven differentially expressed miRNAs (DEMs) showing relatively high expression levels (>1000 TPM (Transcripts per kilobase of exon model per million mapped reads)). The expression patterns of these seven core DEMs and their putative target genes were analyzed in the ovaries of B. dorsalis. The results indicate that Ago-1 and Ago-1-dependent miRNAs are indispensable for normal ovarian development in B. dorsalis and help identify miRNA targets useful for control of this pest.

Polycystic ovary syndrome: Pathways and mechanisms for possible increased susceptibility to COVID-19.

In 75% of women with polycystic ovary syndrome (PCOS), insulin action is impaired. In obesity, visceral adipose tissue becomes dysfunctional: Chronic inflammation is favored over storage, contributing to the development of metabolic complications. PCOS, metabolic syndrome (MetSy) and non-alcoholic fatty liver disease (NAFLD) apparently share common pathogenic factors; these include abdominal adiposity, excess body weight and insulin resistance. Alterations in the gut microbiome have been noted in women with PCOS compared to controls; these may lead to deterioration of the intestinal barrier, increased gut mucosal permeability and immune system activation, hyperinsulinemia and glucose intolerance, which hamper normal ovarian function and follicular development (all being hallmarks of PCOS). It has been proposed that PCOS may entail higher susceptibility to coronavirus disease 2019 (COVID-19) via its associated comorbidities (NAFLD, obesity, MetSy and alterations in the gut microbiome). Studies have found an association between acute respiratory distress syndrome (seen in severe cases of COVID-19) and the intestinal microbiome. Furthermore, apparently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can gain entry to the gastrointestinal tract via locally-expressed angiotensin converting enzyme type 2 receptors. Excess body weight is associated with more severe COVID-19 and increased mortality. Although robust links between SARS-CoV-2 infection and PCOS/NAFLD/gut microbiome/metabolic consequences are yet to be confirmed, it seems that strategies for adapting the intestinal microbiome could help reduce the severity of COVID-19 in women with PCOS with or without NAFLD, MetSy or obesity.

Developmental and hormonal regulation of ubiquitin-like with plant homeodomain and really interesting new gene finger domains 1 gene expression in ovarian granulosa and theca cells of cattle.

Ubiquitin-like with plant homeodomain and really interesting new gene finger domains 1 (UHRF1) is a multi-domain nuclear protein that plays an important role in epigenetics and tumorigenesis, but its role in normal ovarian follicle development remains unknown. Thus, the present study evaluated if UHRF1 mRNA abundance in bovine follicular cells is developmentally and hormonally regulated, and if changes in UHRF1 are associated with changes in DNA methylation in follicular cells. Abundance of UHRF1 mRNA was greater in granulosa cells (GC) and theca cells (TC) from small (<6 mm) than large (≥8 mm) follicles and was greater in small-follicle GC than TC. In GC and TC, fibroblast growth factor 9 (FGF9) treatment increased (P < 0.05) UHRF1 expression by 2-fold. Also, luteinizing hormone (LH) and insulin-like growth factor 1 (IGF1) increased (P < 0.05) UHRF1 expression in TC by 2-fold, and forskolin (an adenylate cyclase inducer) alone or combined with IGF1 increased (P < 0.05) UHRF1 expression by 3-fold. An E2F transcription factor inhibitor (E2Fi) decreased (P < 0.05) UHRF1 expression by 44% in TC and by 99% in GC. Estradiol, progesterone, and dibutyryl-cAMP decreased (P < 0.05) UHRF1 mRNA abundance in GC. Treatment of GC with follicle-stimulating hormone (FSH) alone had no effect but when combined with IGF1 enhanced the UHRF1 mRNA abundance by 2.7-fold. Beauvericin (a mycotoxin) completely inhibited the FSH plus IGF1-induced UHRF1 expression in small-follicle GC. Treatments that increased UHRF1 mRNA (i.e., FGF9) in GC tended to decrease (by 63%; P < 0.10) global DNA methylation, and those that decreased UHRF1 mRNA (i.e., E2Fi) in GC tended to increase (by 2.4-fold; P < 0.10) global DNA methylation. Collectively, these results suggest that UHRF1 expression in both GC and TC is developmentally and hormonally regulated, and that UHRF1 may play a role in follicular growth and development as well as be involved in ovarian epigenetic processes.

A new type of tetraploid fish derived via female autotetraploid × male allotetraploid hybridization

Based on the production of an allotetraploid fish line (4nAL, 4n = 200, AABB, F3-F28) derived from a cross between female Carassius auratus var. red (RCC, 2n = 100, AA) and male Cyprinus carpio (COC, 2n = 100, BB) and an autotetraploid fish line (4nAU, 4n = 200, AAAA, F2-F14) derived from a cross between female RCC and male Megalobrama amblycephala (BSB, 2n = 48), we obtained a new tetraploid hybrid (4nNT, 4n = 200, AAAB) by crossing 4nAU females with 4nAL males. The aim of this study was to comparatively investigate the biological characteristics of 4nNT fish and their parents. The results regarding the DNA content and chromosome numbers indicated that 4nNT were tetraploid with three sets of RCC-derived chromosomes and one set of COC-derived chromosomes. Histological sectioning showed that female and male 4nNT individuals had normal ovarian and testis development, respectively. Analyses of 5S rDNA molecular organization revealed that the 5S rDNA of 4nNT was inherited from the original parents and contained obvious base variations and sequence insertions or deletions. The newly produced 4nNT hybrid has the potential to establish a new tetraploid fish line, and it also provides an ideal model for studying the genomic structure and genetic expression variation in polyploid hybrid fish.

TOLERANCE OF HETERACRIS LITTORALIS (ORTHOPTERA: ACRIDIDAE) TO THE TOXIC PLANT, NERIUM OLEANDER (APOCYNACEA)

Nerium oleander (Apocynacea) is a highly toxic plant that has never been reported to be selected as a food or even as a resting place by any acridid species. The study tested the competence of Heteracrislittoralis (Orthoptera: Acrididae) to tolerate and survive on this plantfor considerable periods, and to resume normal capacity of development and reproduction when favourable food plant became available. Nymphal survival and development were followed by monitoring three cohorts of freshly hatched hoppers. The first cohort fed oleander leaves; the second one (control) fed clover; while the third cohort fed oleander leaves for 35 days, and then switched to clover. Age specific survivorship and reproductive parameters of the adults were followed by monitoring three cohorts of newly fledged adults fed on the samepatterns. Moulting was suspended in nymphs fed oleander; when food plant was switched to clover, the insects resumed normal development and reached the adult stage. Adult cohort reared on N. oleander exhibited a normal age specific survivorship curve, but ovarian development was suspended. Suspension of ovarian development by N. oleander was accompanied by very low indices of food consumption and conversion of digested food into body substance.But, after switching to normal food, clover, the insects resumed normal ovarian development with significant prolonged longevity, and the fecundity was approximately equal to the same parameter in the control cohort. This reflects a strong evolutionary biotic potential against the selective power of plant defense.

Molecular characterization of the Krüppel-homolog 1 and its role in ovarian development in Sogatella furcifera (Hemiptera: Delphacidae).

Juvenile hormone (JH) plays a pivotal role in insect reproduction. The Krüppel-homolog 1 (Kr-h1) is a JH-inducible zinc finger transcription factor that has also been found to play a role in insect reproduction, however, its function varies across species. In this study, we cloned SfKr-h1 from Sogatella furcifera and investigated its role in ovarian development. The open reading frame of SfKr-h1 is 1 800bp encoding 599 amino acids. The putative amino acid sequence of SfKr-h1 contains eight putative C2H2-type zinc finger domains and is highly homologous with the Kr-h1s of other hemipteran species. Expression of SfKr-h1 peaked 96h after adult emergence and was highest in the ovary. RNA interference (RNAi) knockdown of SfKr-h1 substantially reduced the transcription of SfVg, and arrested ovarian development. These results suggest that SfKr-h1 is critical for normal ovarian development in S. furcifera.

Nr5a1 suppression during the murine fetal period optimizes ovarian development by fine-tuning Notch signaling

The nuclear receptor NR5A1 is equally expressed and required for development of the gonadal primordia of both sexes, but, after sex determination, it is upregulated in XY testes and downregulated in XX ovaries. We have recently demonstrated, in mice, that this downregulation is mediated by forkhead box L2 (FOXL2) and hypothesized that adequate suppression of Nr5a1 is essential for normal ovarian development. Further, analysis of human patients with disorders/differences of sex development suggests that overexpression of NR5A1 can result in XX (ovo)testicular development. Here, we tested the role of Nr5a1 by overexpression in fetal gonads using a Wt1-BAC (bacterial artificial chromosome) transgene system. Enforced Nr5a1 expression compromised ovarian development in 46,XX mice, resulting in late-onset infertility, but did not induce (ovo)testis differentiation. The phenotype was similar to that of XX mice lacking Notch signaling. The expression level of Notch2 was significantly reduced in Nr5a1 transgenic mice, and the ovarian phenotype was almost completely rescued by in utero treatment with a NOTCH2 agonist. We conclude that suppression of Nr5a1 during the fetal period optimizes ovarian development by fine-tuning Notch signaling.

The Role of microRNAs in Ovarian Granulosa Cells in Health and Disease.

The granulosa cell (GC) is a critical somatic component of the ovary. It is essential for follicle development by supporting the developing oocyte, proliferating and producing sex steroids and disparate growth factors. Knowledge of the GC's function in normal ovarian development and function, and reproductive disorders, such as polycystic ovary syndrome (PCOS) and premature ovarian failure (POF), is largely acquired through clinical studies and preclinical animal models. Recently, microRNAs have been recognized to play important regulatory roles in GC pathophysiology. Here, we examine the recent findings on the role of miRNAs in the GC, including four related signaling pathways (Transforming growth factor-β pathway, Follicle-stimulating hormones pathway, hormone-related miRNAs, Apoptosis-related pathways) and relevant diseases. Therefore, miRNAs appear to be important regulators of GC function in both physiological and pathological conditions. We suggest that targeting specific microRNAs is a potential therapeutic option for treating ovary-related diseases, such as PCOS, POF, and GCT.

A clinically functioning gonadotroph adenoma presenting with abdominal pain, ovarian hyperstimulation and fibromatosis.

SummaryPituitary adenomas can be classified as functioning or non-functioning adenomas. Approximately 64% of clinically non-functioning pituitary adenomas are found to be gonadotroph adenomas on immunohistochemistry. There are reported cases of gonadotroph adenomas causing clinical symptoms, but this is unusual. We present the case of a 36-year-old female with abdominal pain. Multiple large ovarian cysts were identified on ultrasound requiring bilateral cystectomy. Despite this, the cysts recurred resulting in further abdominal pain, ovarian torsion and right oophorectomy and salpingectomy. On her 3rd admission with abdominal pain, she was found to have a rectus sheath mass which was resected and histologically confirmed to be fibromatosis. Endocrine investigations revealed elevated oestradiol, follicle-stimulating hormone (FSH) at the upper limit of the normal range and a suppressed luteinising hormone (LH). Prolactin was mildly elevated. A diagnosis of an FSH-secreting pituitary adenoma was considered and a pituitary MRI revealed a 1.5 cm macroadenoma. She underwent transphenoidal surgery which led to resolution of her symptoms and normalisation of her biochemistry. Subsequent pelvic ultrasound showed normal ovarian follicular development. Clinically functioning gonadotroph adenomas are rare, but should be considered in women presenting with menstrual irregularities, large or recurrent ovarian cysts, ovarian hyperstimulation syndrome and fibromatosis. Transphenoidal surgery is the first-line treatment with the aim of achieving complete remission.Learning points:Pituitary gonadotroph adenomas are usually clinically non-functioning, but in rare cases can cause clinical symptoms.A diagnosis of a functioning gonadotroph adenoma should be considered in women presenting with un-explained ovarian hyperstimulation and/or fibromatosis.In women with functioning gonadotroph adenomas, the main biochemical finding is elevated oestradiol levels. Serum FSH levels can be normal or mildly elevated. Serum LH levels are usually suppressed.Transphenoidal surgery is the first-line treatment for patients with functioning gonadotroph adenomas, with the aim of achieving complete remission.