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The transcription factor p63 guards genome integrity in the female germline, and its mutations have been reported in patients with premature ovarian insufficiency (POI). However, the precise contribution of the TP63 gene to the pathogenesis of POI needs to be further determined. Here, in 1,030 Chinese patients with POI, we identified 6 heterozygous mutations of the TP63 gene that impaired the C-terminal transactivation-inhibitory domain (TID) of the TAp63[alpha] protein and resulted in tetramer formation and constitutive activation of the mutant proteins. The mutant proteins induced cell apoptosis by increasing the expression of apoptosis-inducing factors in vitro. We next introduced a premature stop codon and selectively deleted the TID of TAp63[alpha] in mice and observed rapid depletion of the [p63.sup.+/[DELTA]TID] mouse oocytes through apoptosis after birth. Finally, to further verify the pathogenicity of the mutation p.R647C in the TID that was present in 3 patients, we generated [p63.sup.+/R647C] mice and also found accelerated oocyte loss, but to a lesser degree than in the [p63.sup.+[DELTA]TID] mice. Together, these findings show that TID-related variants causing constitutive activation of TAp63[alpha] lead to POI by inducing oocyte apoptosis, which will facilitate the genetic diagnosis of POI in patients and provide a potential therapeutic target for extending female fertility., Introduction Premature ovarian insufficiency (POI) is characterized by the decline of ovary activity, with increasing follicle-stimulating hormone (FSH) levels (FSH >25 IU/L) and low estradiol (E2) levels before the age [...]

STUDY QUESTION Are variants of genes involved in meiosis initiation responsible for premature ovarian insufficiency (POI)? SUMMARY ANSWER A MEIOSIN variant participates in the pathogenesis of human POI by impairing meiosis due to insufficient transcriptional activation of essential meiotic genes. WHAT IS KNOWN ALREADY Meiosis is the key event for the establishment of the ovarian reserve, and several gene defects impairing meiotic homologous recombination have been found to contribute to the pathogenesis of POI. Although STRA8 and MEIOISN variants have been found to associate with POI in a recent study, the condition of other meiosis initiation genes is unknown and direct evidence of variants participating in the pathogenesis of POI is still lacking. STUDY DESIGN, SIZE, DURATION This was a retrospective genetic study. An in-house whole exome sequencing (WES) database of 1030 idiopathic POI patients was screened for variations of meiosis initiation genes. PARTICIPANTS/MATERIALS, SETTING, METHODS Homozygous or compound heterozygous variations of genes involved in meiosis initiation were screened in the in-house WES database. The pathogenicity of the variation was verified by in vitro experiments, including protein structure prediction and dual-luciferase reporter assay. The effect of the variant on ovarian function and meiosis was demonstrated through histological analyses in a point mutation mouse model. MAIN RESULTS AND THE ROLE OF CHANCE One homozygous variant in MEIOSIN (c.1735C>T, p.R579W) and one in STRA8 (c.258 + 1G>A), which initiates meiosis via the retinoic acid-dependent pathway, were identified in a patient with idiopathic POI respectively. The STRA8 variation has been reported in the recently published work. For the MEIOSIN variation, the dual-luciferase reporter assay revealed that the variant adversely affected the transcriptional function of MEIOSIN in upregulating meiotic genes. Furthermore, knock-in mice with the homologous mutation confirmed that the variation impacted the meiotic prophase I program and accelerated oocyte depletion. Moreover, the variant p.R579W localizing in the high-mobility group (HMG) box domain disrupted the nuclear localization of the MEIOSIN protein but was dispensable for the cell-cycle switch of oocytes, suggesting a unique role of the MEIOSIN HMG box domain in meiosis initiation. LIMITATIONS, REASONS FOR CAUTION Further studies are needed to explore the role of other meiosis initiation genes in the pathogenesis of POI. WIDER IMPLICATIONS OF THE FINDINGS The MEIOSIN variant was verified to cause POI by impaired transcriptional regulation of meiotic genes and was inherited by a recessive mode. The function of HMG box domain in MEIOSIN protein was also expanded by this study. Although causative variations in meiotic initiation genes are rare in POI, our study confirmed the pathogenicity of a MEIOSIN variant and elucidated another mechanism of human infertility. STUDY FUNDING/COMPETING INTEREST(s) This work was supported by the National Key Research & Developmental Program of China (2022YFC2703800, 2022YFC2703000), National Natural Science Foundation for Distinguished Young Scholars (82125014), National Natural Science Foundation of China (32070847, 32170867, 82071609), Basic Science Center Program of NSFC (31988101), Natural Science Foundation of Shandong Province for Grand Basic Projects (ZR2021ZD33), Natural Science Foundation of Shandong Province for Excellent Young Scholars (ZR2022YQ69), Taishan Scholars Program for Young Experts of Shandong Province (tsqn202211371), and Qilu Young Scholars Program of Shandong University. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Ovarian granulosa cells (GCs) proliferate and differentiate along with follicular growth, and this is indispensable for oocyte development and female fertility. Although the role of macroautophagy/autophagy in ovarian function has been reported, its contribution to the regulation of GC characteristics remains elusive. The siRNA-mediated knockdown of two key autophagy-related genes ATG5 and BECN1 and the autophagy inhibitor chloroquine were used to interfere with autophagy in GCs. Inhibition of autophagy both genetically and pharmacologically resulted in decreased expression of genes associated with GC differentiation, including CYP19A1/Aromatase and FSHR, as well as in reduced estradiol synthesis. Mechanistically, when autophagy was disrupted, the transcription factor WT1 accumulated in GCs due to its insufficient degradation by the autophagic pathway, and this inhibited GC differentiation. Finally, decreased expression of several autophagy-related genes, as well as reduced LC3-II:LC3-I and elevated SQSTM1/p62 protein levels, which are indications of decreased autophagy, were detected in GCs from biochemical premature ovarian insufficiency patients. In summary, our study reveals that autophagy regulates the differentiation of ovarian GCs by degrading WT1 and that insufficient autophagy might be involved in ovarian dysfunction. Abbreviations: ATG: autophagy related; bPOI: biochemical premature ovarian insufficiency; CHX: cycloheximide; Co-IP: co-immunoprecipitation; CQ: chloroquine; E2: estradiol; FSH: follicle stimulating hormone; FSHR: follicle stimulating hormone receptor; GC: granulosa cell; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; POI: premature ovarian insufficiency; RAP: rapamycin; siRNA: small interfering RNA; WT1: WT1 transcription factor [ABSTRACT FROM AUTHOR]

Immune dysregulation has long been proposed as a component of premature ovarian insufficiency (POI), but the underlying mediators and mechanisms remain largely unknown. Here we showed that patients with POI had augmented T helper 1 (TH1) responses and regulatory T (Treg) cell deficiency in both the periphery and the ovary compared to the control women. The increased ratio of TH1:Treg cells was strongly correlated with the severity of POI. In mouse models of POI, the increased infiltration of TH1 cells in the ovary resulted in follicle atresia and ovarian insufficiency, which could be prevented and reversed by Treg cells. Importantly, interferon (IFN) ‐γ and tumor necrosis factor (TNF) ‐α cooperatively promoted the apoptosis of granulosa cells and suppressed their steroidogenesis by modulating CTGF and CYP19A1. We have thus revealed a previously unrecognized Treg cell deficiency‐mediated TH1 response in the pathogenesis of POI, which should have implications for therapeutic interventions in patients with POI. [ABSTRACT FROM AUTHOR]

Distinct microRNA (miRNA) profiles have been reported in premature ovarian insufficiency (POI), but their functional relevance in POI is not yet clearly stated. In this study, aberrant expressions of miR‐127‐5p and high mobility group box 2 (HMGB2) were observed by microarrays in granulosa cells (GCs) from biochemical POI (bPOI) women and further confirmed by a quantitative reverse‐transcription polymerase chain reaction. Immortalized human granulosa cell line and mouse primary ovarian GCs were used for functional validation. Orthotopic mouse model was established to examine the role of miR‐127‐5p in vivo. Finally, the expression of miR‐127‐5p was measured in the plasma of bPOI women. The receiver operating characteristic curve analysis was performed to determine the indicative role of miR‐127‐5p for ovarian reserve. Results showed the upregulation of miR‐127‐5p was identified in GCs from bPOI patients. It inhibited GCs proliferation and impaired DNA damage repair capacity through targeting HMGB2, which was significantly downregulated in GCs from the same cohort of cases. miR‐127‐5p was confirmed to attenuate DNA repair capability via HMGB2 in mouse ovary in vivo. Intriguingly, the upexpression of miR‐127‐5p was also detected in plasma of bPOI individuals, suggesting that miR‐127‐5p could be a promising indicator for bPOI. Taken together, our results discovered the deleterious effects of miR‐127‐5p on GCs function and its predictive value in POI process. The target gene HMGB2 could be considered as a new candidate for POI. This study highlights the importance of DNA repair capacity for ovarian function and sheds light on the epigenetic mechanism in the pathogenicity of POI. [ABSTRACT FROM AUTHOR]

Problem: Premature ovarian insufficiency (POI) imposes great challenge on female reproduction. Whether immune disturbance in ovarian environment was implicated in POI remains unclear. We aimed to characterize the cytokine profile in follicular fluid (FF) and paired serum in patients with biochemical POI (bPOI). Method of study: Multiplex immunoassay containing 45 cytokines was performed for individual FF and paired serum samples from 35 bPOI patients and 37 matched controls. Cytokine profiles were compared between the two groups and cytokines correlated to ovarian reserve, and the rates of day‐3 good‐quality embryos were further analyzed. Results: In FF, significantly elevated level of chemokines MIP‐1α (P =.043), CXCL8 (P =.024), IP‐10 (P =.041), and eotaxin‐1 (P =.015) as well as growth factors VEGF‐D (P =.047), BDNF (P =.043), LIF (P =.002), and bFGF (P =.046) was found in bPOI patients compared to controls. Yet RANTES manifested an opposite trend with reduced levels among bPOI patients (P =.006). All these chemokines and growth factors in FF were significantly correlated with ovarian reserve (P <.05). In paired serum, cytokine signature was not likely accordant with that in FF between two groups, except for increased IP‐10 (P =.032) in bPOI patients and its significant correlation to FSH and AFC (P <.05). Among all differentially expressed cytokines, RANTES in FF was correlated with the rate of day‐3 good‐quality embryos (P =.035). Conclusion: Altered cytokine profile characterized by increased chemokines and growth factors was associated with early stage of POI, which may fuel the progression of the disease or even play a crucial role in the development of ovarian insufficiency. [ABSTRACT FROM AUTHOR]

Context: Premature ovarian insufficiency (POI) is characterized by cessation of menstruation before 40 years of age and elevated serum level of FSH (>25 IU/L). Recent studies have found a few causative genes responsible for POI enriched in meiotic recombination and DNA damage repair pathways.Objective: To investigate the role of variations in homologous recombination genes played in POI pathogenesis.Methods: The whole exome sequencing was performed in 50 POI patients with primary amenorrhea. Functional characterizations of the novel variants were carried out in budding yeast and human cell line.Results: We identified 8 missense variants in 7 homologous recombination genes, including EXO1, RAD51, RMI1, MSH5, MSH2, MSH6, and MLH1. The mutation p.Thr52Ser in EXO1 impaired the meiotic process of budding yeast and p.Glu68Gly in RAD51-altered protein localization in human cells, both of them impaired the efficiency of homologous recombination repair for DNA double-stranded breaks in human cells.Conclusions: Our study first linked the variants of EXO1 and RAD51 with POI and further highlighted the role of DNA repair genes in ovarian dysgenesis. [ABSTRACT FROM AUTHOR]

In the mammalian ovaries, dormant primordial follicles represent the reproductive reserve of individual females. Recently, stimulating the activation of primordial follicles in vitro has been practiced, making the utilization of those dormant follicles to treat female infertility possible. However, there are still lacks of effective upstream molecule and strategy to elevate follicle activation in vivo. In the current study, we revealed that growth factor EGF improved a transiently primordial follicle activation in mice by elevating the CDC42‐PI3K signaling activity, and EGF treatment also improved the activation and development of human follicles in ovarian cortical pieces. Using a liquid‐solid phase transition bio‐gel as a carrier, an efficient in vivo activation system was established by ovarian topical EGF administration to living mice. We found that EGF treatment led to an increase of primordial follicle activation in short time but had no effect on long‐term fertility in females. By establishing an inducible premature ovarian insufficiency (POI) mouse model through selectively ablating growing follicles in Zp3‐Cre;iDTR mice, we further revealed that our in vivo EGF treatment system improved primordial follicle activation and ovulation of POI ovaries significantly. Taken together, our results revealed that in situ ovarian EGF administration could improve the activation of primordial follicles in living animals, and manipulating activation and development of primordial follicles in vivo might be an efficient approach to improve reproductive health in women. [ABSTRACT FROM AUTHOR]

Sox8, encoding a SRY‐related HMG box transcription factor, is essential in Sertoli cells for germ cell differentiation via regulation of integrity of the blood–testis barrier (BTB) as well as Sertoli‐germ cell adhesion. Inactivation of Sox8 gene in mice causes postnatal progressive spermatogenic failure, resulting in male infertility. This study aims to investigate whether variants of SOX8 contribute to pathogenesis of idiopathic non‐obstructive azoospermia (NOA) or oligozoospermia. A case–control genetic study was conducted in which all exons and exon–intron boundaries of SOX8 gene were screened in 190 NOA and 139 oligozoospermia cases by Sanger sequencing. The detected variants were examined in 284 normospermic controls. Nine known single‐nucleotide polymorphisms (SNPs) of SOX8 gene were identified, and four of them exist simultaneously in oligo/azoospermia patients. A comparison of allele/genotype frequencies of these variants showed no significant difference between oligo/azoospermia cases and controls. The results indicate that deleterious variants in SOX8 gene may not be a common cause for oligo/azoospermia in Chinese men. Considering ethnic diversity, SOX8 could not be ruled out as a candidate gene for male infertility. The role of SOX8‐mediated Sertoli cell function and BTB integrity played in the pathogenesis of male infertility needs to be further explored in other populations. [ABSTRACT FROM AUTHOR]

The Fanconi anemia (FA) pathway is mainly involved in DNA interstrand crosslinks (ICLs) repair in the genome. Several FA genes, including FANCD1/BRCA2, FANCM, and FANCU/XRCC2, have been identified as causative genes for premature ovary insufficiency (POI). Fanconi anemia group L protein (FANCL) cooperates with FANCT/UBE2T to ubiquitinate the FANCI‐D2 dimer, which is a crucial event in the process of ICLs repair. Fancl‐knockout mice phenocopy human POI, but the role of FANCL mutations in POI pathogenesis has not been confirmed. In the present work, potentially pathogenic mutations in the FANCL gene were screened in 200 Chinese patients with idiopathic POI and in 200 matched controls. Two novel heterozygous frameshift mutations, c.1048_1051delGTCT (p.Gln350Valfs*18) and c.739dupA (p.Met247Asnfs*4), were identified in the FANCL gene in POI patients but not in controls. Wild‐type FANCL protein was predominantly localized in the nuclei, while both mutant FANCL proteins were retained in the cytoplasm. In addition, the FANCL variants exhibited impaired ubiquitin‐ligase activity and compromised DNA repair ability after mitomycin C treatment. Furthermore, the FANCL variants were deleterious and might be associated with haploinsufficiency. Our results show that FANCL mutations are potentially causative for POI by disrupting DNA damage repair processes. [ABSTRACT FROM AUTHOR]

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Accumulating evidence has indicated that the genes involved in meiosis are highly correlated with ovarian function. Pumilio 1 (PUM1) is a RNA-binding protein which is involved in the meiotic process. It has been reported that the Pum1 knockout female mice displayed subfertility due to the decrease in primordial follicle pool. The aim of our study is to investigate whether variants of the PUM1 gene are responsible for primary ovarian insufficiency (POI) in Chinese women. We analyzed coding sequence and untranslated regions of the PUM1 gene in 196 Han Chinese women with non-syndromic POI and 192 controls. Seven novel variants were identified, but one of them was synonymous and six were intronic. Besides, seven known single-nucleotide polymorphisms (SNPs) were found, and there were no significant differences in genotype and allele frequencies of the SNPs between patients and controls. The results suggest that the variants in PUM1 may not contribute to POI in Han Chinese women. [ABSTRACT FROM AUTHOR]

Premature ovarian failure (POF) is a rare, heterogeneous disorder characterized by cessation of menstruation occurring before the age of 40 years. Genetic etiology is responsible for perhaps 25% of cases, but most cases are sporadic and unexplained. In this study, through whole exome sequencing in a non-consanguineous family having four affected members with POF and Sanger sequencing in 432 sporadic cases, we identified three novel mutations in the fusion gene CSB-PGBD3. Subsequently functional studies suggest that mutated CSB-PGBD3 fusion protein was impaired in response to DNA damage, as indicated by delayed or absent recruitment to damaged sites. Our data provide the first evidence that mutations in the CSB-PGBD3 fusion protein can cause human disease, even in the presence of functional CSB, thus potentially explaining conservation of the fusion protein for 43 My since marmoset. The localization of the CSB-PGBD3 fusion protein to UVA-induced nuclear DNA repair foci further suggests that the CSB-PGBD3 fusion protein, like many other proteins that can cause POF, modulates or participates in DNA repair. [ABSTRACT FROM AUTHOR]

Background: The etiology of most premature ovarian failure (POF) cases is usually elusive. Although genetic causes clearly exist and a likely susceptible region of 8q22.3 has been discovered, no predominant explanation exists for POF. More recently, evidences have indicated that mutations in NR5A1 gene could be causative for POF. We therefore screened for mutations in the NR5A1 gene in a large cohort of Chinese women with non-syndromic POF. Methods: Mutation screening of NR5A1 gene was performed in 400 Han Chinese women with well-defined 46,XX idiopathic non-syndromic POF and 400 controls. Subsequently, functional characterization of the novel mutation identified was evaluated in vitro. Results: A novel heterozygous missense mutation [c.13T>G (p.Tyr5Asp)] in NR5A1 was identified in 1 of 384 patients (0.26%). This mutation impaired transcriptional activation on Amh, Inhibin-a, Cyp11a1 and Cyp19a1 gene, as shown by transactivation assays. However, no dominant negative effect was observed, nor was there impact on protein expression and nuclear localization. Conclusions: This novel mutation p.Tyr5Asp, in a novel non-domain region, is presumed to result in haploinsufficiency. Irrespectively, perturbation in NR5A1 is not a common explanation for POF in Chinese. [ABSTRACT FROM AUTHOR]

Abstract: Folic acid has been shown to decrease the incidence of neural tube defects (NTDs) in normal and hyperglycemic conditions, but the influence of folic acid on the development of central nervous system is not fully understood. Here, we aimed to explore the effects of folic acid, especially high dose of folic acid, on the characteristics of neural progenitors in embryos of hyperglycemic and diabetic mouse. Hyperglycemic and diabetic pregnant mice were given 3 mg/kg or 15 mg/kg folic acid from embryonic day 0.5 (E0.5) and were euthanased on E11.5, E13.5 or E18.5. The incidence of NTDs at E13.5 was counted. The proliferation, apoptosis and differentiation of neural progenitors and neuronal migration were determined using BrdU incorporation assay, TUNEL assay, immunofluorescence, Western blot and real-time reverse transcriptase polymerase chain reaction. Both normal and high doses of folic acid decreased the incidence of NTDs, promoted proliferation and reduced apoptosis of neuroepithelial cells in embryos of hyperglycemic and diabetic mice. Importantly, folic acid, especially at high dose, might affect the premature differentiation of neural progenitors in embryos of hyperglycemic and diabetic pregnancy. This may be attributed to changes of messenger RNA expression levels of some basic–helix–loop–helix transcription factors. In addition, folic acid might be involved in regulating neuronal migration in embryos of hyperglycemic and diabetic pregnancy. These findings suggest that periconceptional supplementation of folic acid, especially at high dose, may be a double-edged sword because it may result in undesirable outcomes affecting both the neuronal and glial differentiation in hyperglycemic and diabetic pregnancy. [Copyright &y& Elsevier]

Diets rich in SFA have been implicated in Alzheimer's disease (AD). There is strong evidence to suggest that microglial activation augments the progression of AD. However, it remains uncertain whether SFA can initiate microglial activation and whether this response can cause neuronal death. Using the BV-2 microglial cell line and primary microglial culture, we showed that palmitic acid (PA) and stearic acid (SA) could activate microglia, as assessed by reactive morphological changes and significantly increased secretion of pro-inflammatory cytokines, NO and reactive oxygen species, which trigger primary neuronal death. In addition, the mRNA level of these pro-inflammatory mediators determined by RT-PCR was also increased by PA and SA. We further investigated the intracellular signalling mechanism underlying the release of pro-inflammatory mediators from PA-activated microglial cells. The present results showed that PA activated the phosphorylation and nuclear translocation of the p65 subunit of NF-κB. Furthermore, pyrrolidine dithiocarbamate, a NF-κB inhibitor, attenuated the production of pro-inflammatory mediators except for IL-6 in PA-stimulated microglia. Administration of anti-Toll-like receptor (TLR)4-neutralising antibody repressed PA-induced NF-κB activation and pro-inflammatory mediator production. In conclusion, the present in vitro study demonstrates that SFA could activate microglia and stimulate the TLR4/NF-κB pathway to trigger the production of pro-inflammatory mediators, which may contribute to neuronal death. [ABSTRACT FROM PUBLISHER]