Local glucose elevation activates pyroptosis via NLRP3 inflammasome in ovarian granulosa cells of overweight patients.

Overweight, with an increasing prevalence worldwide, significantly impairs the clinical outcomes following in vitro fertilization (IVF). Hyperglycemia, hyperlipidemia, and metabolic disorders are always accompanied by the majority of overweight patients. The association between granulosa cell function and metabolic alterations in follicular fluid including lipids, proteins, and growth factors has been extensively documented. However, the effects of higher glucose level on ovarian granulosa cells (GCs), remain largely unknown. In this study, we identified that overweight women had elevated follicular glucose level which profoundly activated NLRP3 inflammasome and pyroptosis. An in vitro correlation between follicular high glucose, NLRP3 inflammasome and pyroptosis was also established. More importantly, in granulosa cells of overweight patients, the activation of the NLRP3 inflammasome and pyroptosis induced by high glucose was involved in the dysregulation of estradiol synthesis. Our study may provide new options to interpretate and improve IVF outcomes in overweight women.

Identification, characterization and expression analysis of rLcn13, an epididymal lipocalin in rats.

As the essential tissue for sperm maturation and storage, the epididymis secretes a number of tissue-specific proteins to exert its functions. Among these proteins, epididymal lipocalins have been intensively studied because of their epididymis-specific expression pattern and clustered genomic organization. In this study, rLcn13, a member of the rat epididymal lipocalin family, is identified and elaborately characterized. The cDNA sequence of rLcn13 consists of 719 nucleotides and encodes a 176 amino-acid protein with a predicted N-terminal signal peptide of 19 amino acids. rLcn13 shares a similar genomic structure and predicted 3D protein structure with other lipocalin family members. A recombinant rLCN13 mature peptide of 157 amino acids is expressed and purified, which is used to raise a polyclonal antibody against rLCN13 with high specificity and sensitivity. Northern blot, western blot, and immunohistochemistry assays reveal that rLcn13 is an epididymis-specific gene which is expressed predominantly in the initial segment and proximal caput epididymis and influenced by androgen. The rLCN13 protein is modified by N-glycosylation and secreted into the epididymal lumen, and then binds to the acrosome region of the sperm. Our data demonstrate that rLcn13 exhibits a specific temporospatial expression pattern and androgen dependence, indicating its potential roles in sperm maturation.

Identification of HOXA10 target genes in human endometrial stromal cells by RNA-seq analysis.

Homeobox A10 (HOXA10) is a transcription factor belonging to the homeobox gene family. It is highly expressed in endometrial stromal cells (ESCs) and plays essential roles in the proliferation and differentiation of endometrium, the establishment of endometrial receptivity and embryo implantation. However, little is known about the target genes and signaling pathways regulated by HOXA10 in ESCs. In this study, we identified 1830 transcripts regulated by HOXA10 in ESCs by RNA interference (RNAi) and RNA-sequencing (RNA-seq) analysis, of which 980 were positively regulated by HOXA10 and 850 were negatively regulated by HOXA10. Interestingly, matrix metallopeptidase-11 was downregulated by HOXA10 in stromal cells verified by quantitative real-time polymerase chain reaction and western blot analysis. Pathway analysis demonstrated that the target genes were enriched in various pathways, including cellular metabolism, DNA replication and repair, cell junction, and lysosome and signal transduction. The results of the present study provide novel insights into the mechanism underlying HOXA10 regulation in ESCs and may identify novel targets for the diagnosis and treatment of endometrium-related infertility.

Expression of tamoxifen-inducible CRE recombinase in Lcn5-CreERT2 transgenic mouse caput epididymis.

The epididymis, which connects the testis to vas deferens, plays a crucial role regulating sperm maturation and fertilization. Here, a tamoxifen-inducible CreERT2 recombinase transgenic mouse was generated to study the function of genes in the caput epididymis using the Cre/LoxP system, which is driven by the 1.8-kb Lcn5 promoter (Lcn5-CreERT2 ). Both CRE recombinase and ERT2 mRNA were specifically expressed in the caput epididymis, beginning at postnatal Day 30 and increasing thereafter. Crossing these Lcn5-CreERT2 transgenic mice with Rosa26; mT/mG reporter mice, which express membrane-bound GFP (mGFP) only after CRE is active at its genetic locus, resulted in the presence of GFP only in the middle/distal caput epididymis after tamoxifen induction. Efficiency of the CRE recombinase production in the caput epididymis was dose- and time-dependent. These tamoxifen-inducible caput epididymis-specific CRE recombinase transgenic mice thus provides a simple approach to modulate epididymal principal cells in vivo, allowing for the genetic investigation of caput epididymis-specific gene functions during sperm maturation. 84: 257-264, 2017. © 2016 Wiley Periodicals, Inc.

An androgen receptor-microrna-29a regulatory circuitry in mouse epididymis.

MicroRNAs are involved in a number of cellular processes; thus, their deregulation is usually apt to the occurrence of diverse diseases. Previous studies indicate that abnormally up-regulated miR-29a is associated with several diseases, such as human acute myeloid leukemia and diabetes; therefore, the proper level of miR-29a is critical for homeostasis. Herein, we observed that miR-29a was repressed by androgen/androgen receptor signaling in mouse epididymis by targeting a conserved androgen response element located 8 kb upstream of miR-29b1a loci. It is well known that multiple regulatory programs often form a complicated network. Here, we found that miR-29a reversibly suppressed androgen receptor and its target genes by targeting IGF1 and p53 pathways. miR-29b1a-overexpressing transgenic mice displayed epididymis hypoplasia partially similar to the phenotype of those mice with an impaired androgen-androgen receptor signal system. Taken together, the results demonstrated that there is a regulatory circuitry between the androgen signaling pathway and miR-29a in mouse epididymis that may be vital for epididymal development and functions.

Androgenic regulation of beta-defensins in the mouse epididymis.

BACKGROUND: The majority of beta-defensin family members are exclusively expressed in the epididymis, and some members have been shown to play essential roles in sperm maturation and fertility in rats, mice and humans. Therefore, beta-defensins are hypothesized to be potential targets for contraception and infertility diagnosis and treatment. Clarifying the regulatory mechanisms for the expression of these genes is necessary. Androgen/androgen receptor (AR) signaling plays an important regulatory role in epididymal structure and function. However, very little is known about the androgenic regulation on the production and secretion of the epididymal beta-defensins. METHODS: The expression of beta-defensins was detected by quantitative RT-PCR. The androgen dependence of beta-defensins was determined by bilateral orchiectomy and androgen supplementation. The androgen response elements (AREs) in the promoters of beta-defensins were identified using the MatInspector software. The binding of AR to AREs was assayed by ChIP-PCR/qPCR. RESULTS: We demonstrated that 23 mouse caput epididymal beta-defensins were differentially regulated by androgen/androgen receptor. Six genes, Defb18, 19, 20, 39, 41, and 42, showed full regulation by androgens. Ten genes, Defb15, 30, 34, 37, 40, 45, 51, 52, 22 and Spag11a, were partially regulated by androgens. Defb15, 18, 19, 20, 30, 34, 37, 39, 41, 42, 22 and Spag11a were associated with androgen receptor binding sites in their promoter or intronic regions, indicating direct regulation of AR. Six genes, Defb1, 12, 13, 29, 35, and spag11b/c, exhibited an androgen-independent expression pattern. One gene, Defb25, was highly dependent on testicular factors rather on androgens. CONCLUSIONS: The present study provides novel insights into the mechanisms of androgen regulation on epididymal beta-defensins, enabling a better understanding of the function of beta-defensins in sperm maturation and fertility.

Attenuation of palmitic acid-induced lysyl oxidase overexpression in the ovary contributes to the improvement of ovulation in obesity by metformin.

STUDY QUESTION: Does palmitic acid (PA), the most common saturated free fatty acid (FFA) in individuals with obesity, contribute to anovulation through upregulation of the collagen-crosslinking enzyme lysyl oxidase (LOX) in the ovary? SUMMARY ANSWER: Increased PA in individuals with obesity can cause LOX upregulation via the activation of hypoxia-inducible factor-1α (HIF-1α), resulting in abnormal collagen deposition in the ovary and anovulation, which can be ameliorated by metformin therapy. WHAT IS KNOWN ALREADY: The underlying cause of anovulation in individuals with obesity is poorly defined, and accumulating evidence indicates that hormonal disturbance, insulin resistance, and inflammation may all play a role in the development of ovulation disorders in individuals with obesity. However, it remains to be determined whether PA plays a role in the regulation of LOX expression, thus disrupting ovarian extracellular matrix (ECM) remodelling in the ovary and resulting in impaired ovulation in individuals with obesity. STUDY DESIGN SIZE DURATION: PA concentration and LOX protein abundance and activity in follicular fluid and ovarian tissue were compared between control (n = 21) subjects, patients with obesity with ovulation (n = 22), and patients with obesity with anovulation (n = 16). The effect of PA on LOX protein expression, and the underlying mechanism, was examined in primary human granulosa cells in vitro. The improvements in obesity conditions induced by LOX inhibition combined with metformin were investigated in a high-fat diet-induced obese rat model. PARTICIPANTS/MATERIALS SETTING METHODS: The abundance of PA concentration and LOX activity was measured via a LOX activity assay and ELISA, respectively. The effect of PA on LOX protein expression was examined in the presence or absence of inhibitors of signalling molecules and siRNA-mediated knockdown of the putative transcription factor. Chromatin immunoprecipitation assays were subsequently conducted to further identify the responsible transcription factor. The role of metformin in the treatment of anovulation by LOX inhibition was investigated in a high-fat diet (HFD)-induced obese rat model. The numbers of retrieved total oocytes and metaphase II oocytes were recorded upon ovarian stimulation. Masson's trichrome staining was used to measure the total collagen content, and immunohistochemical staining and western blotting were used to measure LOX, HIF-1α, and collagen I and IV in the ovary. MAIN RESULTS AND THE ROLE OF CHANCE: Significantly increased FFA, LOX, and collagen abundance were observed in the ovaries of obese women with anovulation, compared to healthy controls or obese women with ovulation. In a HFD-induced obese rat model, metformin corrected the distortion of ovarian morphology by decreasing LOX and collagen protein abundance in the ovary and improving oestrous cyclicity and ovulation. PA increased LOX expression via the activation of HIF-1α in human granulosa cells, which was attenuated by metformin. LARGE SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: Several other saturated and polyunsaturated FFAs, such as stearic acid and arachidonic acid, are also increased in the blood of individuals with obesity, and increased levels of other FFAs may also contribute to the development of anovulation in individuals with obesity, which needs to be further verified in the future. WIDER IMPLICATIONS OF THE FINDINGS: Elevated PA in individuals with obesity can cause LOX dysregulation via activation of HIF-1α, resulting in abnormal collagen deposition in the ovary and anovulation. This dysregulation can be ameliorated by metformin therapy through its local effect on ECM remodelling in the ovary, which is independent of its systemic effect on insulin sensitivity and chronic inflammation. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the National Natural Science Foundation of China (grant numbers 82101730, 82130046, and 31900598) and Innovative Research Team of High-level local Universities in Shanghai (SHSMU-ZLCX20210201). All the authors declare no conflicts of interest in relation to this work.

Ovarian ferroptosis induced by androgen is involved in pathogenesis of PCOS.

STUDY QUESTION: Does ovarian ferroptosis play an active role in the development of polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: Increased ovarian ferroptosis was present in PCOS ovaries and the inhibition of ferroptosis with ferrostatin-1 (Fer-1) ameliorated polycystic ovary morphology and anovulation. WHAT IS KNOWN ALREADY: Programmed cell death plays a fundamental role in ovarian follicle development. However, the types and mechanisms of cell death involved in the ovary are yet to be elucidated. Ferroptosis is a recently discovered iron-dependent programmed cell death. Impaired iron metabolism and cell death have been observed in women with PCOS, the main cause of anovulatory infertility. Additionally, previous studies reported that an abnormal expression of noncoding RNA may promote ferroptosis in immortalized ovarian granulosa cell lines. However, little is known about whether ovarian ferroptosis is increased in PCOS, and there is insufficient direct evidence for a role of ferroptosis in PCOS, and the underlying mechanism. Moreover, the effect of the inhibition of ferroptosis with Fer-1 in PCOS remains unclear. STUDY DESIGN SIZE DURATION: Ferroptosis was evaluated in human granulosa cells (hGCs) from non-PCOS (n = 6-16) and PCOS (n = 7-18) patients. The experimental study was completed in vitro using primary hGCs from women undergoing IVF. Improvements in PCOS indicators following ferroptosis inhibition with Fer-1 were investigated in a dehydroepiandrosterone (DHEA)-induced PCOS rat model (n = 8 per group). PARTICIPANTS/MATERIALS SETTING METHODS: Ovarian ferroptosis was evaluated in the following ways: by detecting iron concentrations via ELISA and fluorescent probes; measuring malondialdehyde (MDA) concentrations via ELISA; assessing ferroptosis-related protein abundance with western blotting; observing mitochondrial morphology with transmission electron microscopy; and determining cell viability. Primary hGCs were collected from women undergoing IVF. They were treated with dihydrotestosterone (DHT) for 24 h. The effect of DHT on ferroptosis was examined in the presence or absence of small interfering RNA-mediated knockdown of the putative receptor coregulator for signaling molecules. The role of ovarian ferroptosis in PCOS progression was explored in vivo in rats. The DHEA-induced PCOS rat model was treated with the ferroptosis inhibitor, Fer-1, and the oocytes and metaphase II oocytes were counted after ovarian stimulation. Additionally, rats were treated with the ferroptosis inducer, RSL3, to further explore the effect of ferroptosis. The concentrations of testosterone, FSH, and LH were assessed. MAIN RESULTS AND THE ROLE OF CHANCE: Increased ferroptosis was detected in the ovaries of patients with PCOS and in rats with DHEA-induced PCOS. Increased concentrations of Fe2+ (P < 0.05) and MDA (P < 0.05), and upregulated nuclear receptor coactivator 4 protein levels, and downregulated ferritin heavy chain 1 (FTH1) and glutathione peroxidase 4 (GPX4) proteins were observed in the hGCs in patients with PCOS and ovaries of PCOS rats (P < 0.05 versus control). DHT was shown to induce ferroptosis via activation of NOCA4-dependent ferritinophagy. The inhibition of ferroptosis with Fer-1 in rats ameliorated a cluster of PCOS traits including impaired glucose tolerance, irregular estrous cycles, reproductive hormone dysfunction, hyperandrogenism, polycystic ovaries, anovulation, and oocyte quality (P < 0.05). Treating rats with RSL3 resulted in polycystic ovaries and hyperandrogenism (P < 0.05). LARGE-SCALE DATA: N/A. LIMITATIONS REASONS FOR CAUTION: Although ovarian-targeted ferroptosis inhibition may be a more targeted treatment for PCOS, the underlying mechanisms in the cycle between ferroptosis and hyperandrogenism require further exploration. Additionally, since PCOS shows high heterogeneity, it is important to investigate whether ferroptosis increases are present in all patients with PCOS. WIDER IMPLICATIONS OF THE FINDINGS: Androgen-induced ovarian ferroptosis appears to play a role in the pathogenesis of PCOS, which potentially makes it a promising treatment target in PCOS. STUDY FUNDING/COMPETING INTERESTS: This study was supported by the National Key R&D Program of China (2023YFC2705500, 2023YFC2705505, 2019YFA0802604), National Natural Science Foundation of China (No. 82130046, 82320108009, 82101708, 82101747, and 82001517), Shanghai leading talent program, Innovative research team of high-level local universities in Shanghai (No. SHSMU-ZLCX20210201, No. SSMU-ZLCX20180401), Shanghai Jiaotong University School of Medicine, Affiliated Renji Hospital Clinical Research Innovation Cultivation Fund Program (RJPY-DZX-003) and Shanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant Support (No. 20161413), Shanghai's Top Priority Research Center Construction Project (2023ZZ02002), and Three-Year Action Plan for Strengthening the Construction of the Public Health System in Shanghai (GWVI-11.1-36). The authors report no competing interests.

Lcn5 promoter directs the region-specific expression of cre recombinase in caput epididymidis of transgenic mice.

Epididymis plays a crucial role in regulating the development of sperm motility and fertilizing capacity. To study the function of genes in the caput epididymidis using the Cre/loxP system, we generated Lcn5-Cre transgenic mice in which the expression of Cre recombinase is driven by the 1.8-kb Lcn5 promoter. A total of 11 founder mice carrying the Lcn5-Cre transgene were identified by PCR from 38 offspring, and the integration efficiency was 28.9%. However, only 1 of the 11 transgenic mouse lines were revealed with the Cre recombinase expressed specifically in caput epididymidis. Furthermore, expression of Cre mRNA was first observed on Postnatal Day 30 and continued to increase during development. Subsequently, Cre protein distribution was assessed by crossing Lcn5-Cre transgenic mice into the mT/mG reporter line. As expected, the Cre recombinase activity was only found in principal cells of the middle/distal caput epididymidis. The tissue-specific expression of Cre protein in the caput epididymidis was further confirmed using Lcn5-Cre mice crossed with a mouse strain carrying Aip1 conditional alleles (Aip1(flox/+)). In summary, a transgenic mouse line expressing Cre recombinase in principal cells of caput epididymidis was established. This transgenic mouse line can be used to generate conditional, caput epididymidis-specific knockout mouse models by crossing with mice harboring floxed (LoxP flanked) genes.

Different effects of androgen on the expression of Fut1, Fut2, Fut4 and Fut9 in male mouse reproductive tract.

The α-(1,2) fucosyltransferases (Fut1 and Fut2) and α-(1,3) fucosyltransferases (Fut4, Fut9) are responsible for the synthesis of Lewis X (LeX) and Lewis Y (LeY) conjugated to glycoproteins. We recently reported that these fucosyltransferases were differentially expressed in the reproductive tract of male mouse. Here, we studied the effect of androgen on fucosyltransferase expression through the use of mouse castration models. We found that Fut1 mRNA and Fut4 mRNA were upregulated, while Fut2 mRNA and Fut9 mRNA were downregulated by androgen in the caput epididymis. However, in the vas deferens and prostate, only Fut4 mRNA and Fut2 mRNA were respectively upregulated following exposure to androgen. In the seminal vesicle, all fucosyltransferases, with the exception of Fut9, were upregulated. We identified the androgen receptor binding sites (ARBSs) of Fut2, Fut4 and Fut9 in the caput epididymis. Luciferase assay for these ARBSs is able to provide an indication as to why Fut4 and Fut9 are differently expressed and regulated by androgen, although they catalyze the same α-(1,3) fucose linkage. Our study showed that androgen could differentially regulate the expression of these fucosyltransferases and provided an insight into the characteristic distribution of each fucosyltransferase responsible for LeX/LeY biosynthesis in the male reproductive tract.

[Androgen/androgen receptor directly regulates the expression of Caveolin-1 in mouse epididymides].

OBJECTIVE: To investigate the mechanisms of androgen/androgen receptor (AR) regulating the expression of Caveolin-1 in the mouse epididymis. METHODS: The AR binding sites associated with the Caveolin-1 gene were identified by searching the database of genomewide AR binding sites in mouse epididymides obtained from chromatin immunoprecipitation-sequencing (ChIP-seq). Total RNA was extracted from the epididymal tissues of normal and castrated mice and those castrated but supplemented with testosterone propionate, and the expression of Caveolin-1 mRNA was detected by RT-PCR and RT-qPCR. ChIP was performed with AR antibodies, and ChIP-PCR and ChIP-qPCR were used to determine the in vivo AR occupancies on the two sites associated with Caveolin-1. RESULTS: Two AR binding sites associated with Caveolin-1 were found in the database, both located in the second intron region. After castration, the expression of Caveolin-1 was significantly increased, 1.8 +/- 0.17 times that of the control group (P < 0.05), and the fold enrichments of the two AR binding sites were dramatically reduced from 13.5 +/- 1.47 and 10.5 +/- 1.03 to 1.05 +/- 0.17 and 1.4 +/- 0.14, respectively (P < 0.01). After androgen supplement, however, the expression of Caveolin-1 was decreased to normal (P < 0.05), and the fold enrichments of the two AR binding sites significantly increased to 16.4 +/- 2.6 and 10 +/- 0.92, respectively (P < 0.01). CONCLUSION: Caveolin-1 is a bona fide AR direct target gene in the mouse epididymis, and its expression is negatively regulated by androgen. These findings have provided a new insight into the androgen/AR regulatory network in mouse epididymides.

iTRAQ-based Proteomic Analysis Unveils ACSL4 as a Novel Potential Regulator of Human Endometrial Receptivity.

Competent endometrial receptivity is a prerequisite for successful embryo implantation. Identification of novel key molecules involved in endometrial receptivity is essential to better interpret human implantation and improve pregnancy rates in assisted reproduction treatment. Isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics was performed to profile the proteomes of the prereceptive (luteinizing hormone [LH] + 2, n = 4) and receptive (LH + 7, n = 4) endometrial tissues. A total of 173 differentially expressed proteins (DEPs) between LH + 2 and LH + 7 endometrial samples were identified. Integrated analysis of the proteomic data and published transcriptomic data was performed to identify the concordant DEPs with differential expression at both the messenger RNA and protein levels. Protein-protein interaction (PPI) network analysis was performed on concordant DEPs. We first identified 63 novel concordant DEPs and 5 hub proteins (ACSL4, ACSL5, COL1A1, PTGS1, and PLA2G4F) between LH + 2 and LH + 7 endometrial samples. ACSL4 was predominantly expressed in endometrial epithelial cells and its expression was significantly upregulated by progesterone in the LH + 7 endometrium and significantly downregulated in repeated implantation failure patients. Knockdown of ACSL4 in endometrial epithelial cells induced the downregulation of endometrial receptivity markers (HOXA10, COX2, and LIF) and the significant decrease of implantation rate during in vitro implantation analysis. This study provides the first gel-independent quantitative proteomes of the LH + 2 and LH + 7 human endometrium using iTRAQ technology. The identified concordant DEPs and hub proteins open a new avenue for future studies aimed at elucidating the underlying mechanisms governing endometrial receptivity. ACSL4 was identified as a novel regulatory molecule in the establishment of endometrial receptivity and might play important roles during implantation.

Novel mutations in PLCZ1 lead to early embryonic arrest as a male factor.

Early embryonic arrest is one of the causes of assist reproduction technology (ART) failure. We have previously reported that the first sperm-derived genetic factor, ACTL7a mutations, could lead to early embryonic arrest. However, whether there are other male genetic factors associated with early embryonic arrest remains elusive. Here, we reported bi-allelic mutations in PLCZ1, a well-known causal gene of total fertilization failure, in four infertile males. Among these mutations, p.403_404del, p.I489S, and p.W536X were newly reported in this study. Histological and Western blotting analysis of the patients' sperm indicated these variants as loss-of-function mutations. These patients manifested normal conventional semen parameters and ultra-structures in sperm heads. However, among four in vitro fertilization (IVF) cycles, 81.8% (18/22) of the oocytes were polyspermic fertilized, which was rarely reported in PLCZ1-related male patients. In the following six ICSI cycles, artificial oocyte activation (AOA) was applied and successfully rescued the fertilization failure and polyspermy phenotypes, with 31.3% (15/48) of the MII oocytes normally fertilized. However, 60.0% (9/15) of these normally fertilized zygotes were arrested at 2-5-cell stage, with one failing to cleave, indicating that PLCZ1 was not only necessary for fertilization, but also crucial for early embryonic development. However, these rescued zygotes showed a lower potential in developing into blastocysts when cultured in vitro. Thus, fresh cleavage transfer was tried and two live births were successfully achieved thereafter. In conclusion, this study provided novel mutations in PLCZ1 gene to expand the pathogenic mutational spectrum in male infertility and demonstrated that PLCZ1 was a crucial sperm-related genetic factor for early embryonic arrest. We also proposed that cleavage transfer after ICSI and AOA treatment could be a potential treatment method for male patients carrying bi-allelic mutations in PLCZ1.

Chronic stress induces meiotic arrest failure and ovarian reserve decline via the cAMP signaling pathway.

Chronic stress is suspected to be a causal factor of female subfertility; however, the underlying mechanisms remain unclear. Here, we found that chronic stress inhibited the cyclic adenosine 3',5'-monophosphate (cAMP) signaling pathway, leading to ovarian reserve decline in mice. A chronic stress model was constructed using restraint stress for 8 weeks. An elongated estrous cycle and a significant increase in the number of atretic follicles were observed in the stress group. We identified a significant increase in meiotic arrest failure (MAF) in oocytes in the stress group, characterized by condensed metaphase chromosomes, assembled spindles, or polar bodies in the oocytes. Whole-mount ovarian reserve estimation at the single-oocyte level using the CUBIC method (clear, unobstructed brain/body imaging cocktails and computational analysis) revealed a significant decrease in quiescent oocytes from 2,261/ovary in the control group to 1,373/ovary in the stress group. The number of growing oocytes also significantly decreased from 220/ovary in the control group to 150/ovary in the stress group. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis of the meiotic arrest maintenance pathways revealed significant downregulation of Gpr3, Nppc, and Npr2 in the stress group. These results indicate that blocking cAMP production contributes to MAF and a decline in ovarian reserve. Overall, we present new insights into the mechanisms underlying chronic-stress-induced oocyte loss and potential targets for ovarian reserve preservation.

CHD7 in oocytes is essential for female fertility.

Background: Chromodomain helicase DNA-binding protein 7 (CHD7), which is associated with CHARGE (Coloboma, Heart defect, Atresia choanae, Restricted growth, Genital hypoplasia and Ear abnormality) syndrome is an important regulator in many vital developmental processes. However, its role during oocyte development remains unknown. Methods: We screened the Gene Expression Omnibus (GEO) database for expression levels of CHD7 during folliculogenesis. We generated a conditional knockout (cKO) mouse strain with oocyte-specific deletion of CHD7 (Gdf9-Cre:Chd7f/f ) using the Cre-loxP approach. Evaluation of follicle numbers and reproductive ability was then conducted. In addition, granulosa cell (GC) apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and cleaved caspase-3, using immunohistochemistry (IHC) and immunofluorescence (IF). GC proliferation was measured by Ki67 staining as evaluated by IHC. Results: In our study, we demonstrated that CHD7 has high expression throughout all developmental stages of the oocyte. We found that deletion of Chd7 in oocytes can cause infertility or sub-fertility in female mice and is associated with decreased follicle numbers at all stages. In addition, we found that GC apoptosis was significantly higher in cKO mice. Conclusions: To our knowledge, our study has been the first to show that CHD7 plays a specific role during oogenesis. Our findings provide new insights into CHD7-related infertility.

Deficiency of Sirtuin 1 Impedes Endometrial Decidualization in Recurrent Implantation Failure Patients.

Decidualization is driven by differentiation of human endometrial stromal cells (ESCs), and is a prerequisite for successful implantation and establishment of pregnancy. The critical role of impaired decidualization in women suffered recurrent implantation failure (RIF) has been established, while the underlying mechanism is poorly understood. In the present study, we verified the essential role of Sirtuin1 (SIRT1) in regulating differentiation and maintaining reactive oxygen species (ROS) homeostasis of human ESCs during decidualization. The abundance of SIRT1 was decreased in RIF patients both in the endometria during window of implantation phase and in the decidualized ESCs. Downregulation of SIRT1 disrupted the intracellular ROS homeostasis during decidualization of ESC, manifested as the accumulation of intracellular ROS level and the reduction of antioxidant stress molecules. Elimination of ROS with N-acetyl-L-cysteine (NAC) could rescued the decidualization inhibition caused by SIRT1 knockdown. Further, we explored the insufficient expression of SIRT1 in ESC affected the deacetylation of forkhead box O1 (FOXO1), and thus inhibited the transcriptional activity of FOXO1. This could account for the dysregulation of intracellular ROS homeostasis during decidualization and decreased expression of decidual markers. Collectively, our findings provided insight into the role of down-regulated SIRT1 in the poor decidual response of ESCs in RIF patients.

Self-Assembly of [3]Catenane and [4]Catenane Based on Neutral Organometallic Scaffolds.

Transition metal-mediated templating and self-assembly have shown great potential to construct mechanically interlocked molecules. Herein, we describe the formation of the bimetallic [3]catenane and [4]catenane based on neutral organometallic scaffolds via the orthogonality of platinum-to-oxygen coordination-driven self-assembly and copper(I) template-directed strategy of a [2]pseudorotaxane. The structures of these bimetallic [3]catenane and [4]catenane were characterized by multinuclear NMR {1H and 31P} spectroscopy, electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), and PM6 semiempirical molecular orbital theoretical calculations. In addition, single-crystal X-ray analyses of the [3]catenane revealed two asymmetric [2]pseudorotaxane units inside the metallacycle. It was discovered that tubular structures were formed through the stacking of individual [3]catenane molecules driven by the strong π-π interactions.

Addressing the role of 11ß-hydroxysteroid dehydrogenase type 1 in the development of polycystic ovary syndrome and the putative therapeutic effects of its selective inhibition in a preclinical model.

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common metabolic and endocrine disorder among reproductive-age women, and the leading cause of anovulatory infertility. 11ß-hydroxysteroid dehydrogenases-1 (11ß-HSD1) catalysing the conversion of inactive cortisone to active cortisol plays a crucial role in various metabolic diseases. However, whether 11ß-HSD1 is associated with the pathogenesis of PCOS and whether 11ß-HSD1 can be a treating target of PCOS remain unknown. METHODS: This study was first designed to explore the role of 11ß-HSD1 in PCOS development and the effect of selective 11ß-HSD1 inhibitor administration on PCOS treatment. Follicular fluid and granulosa cells (GCs) were collected from 32 non-PCOS patients and 37 patients with PCOS to measure cortisol and 11ß-HSDs levels. Female Sprague-Dawley rats (3-week-old) were injected with dehydroepiandrosterone (DHEA) to induce PCOS and their ovaries were collected to measure the abundance of corticosterone (CORT) and 11ß-HSDs. To determine the role of 11ß-HSD1 in PCOS development, we overexpressed 11ß-HSD1 in the ovaries of female rats (5-week-old) or knocked down the expression of 11ß-HSD1 in the ovaries from PCOS rats via lentivirus injection. After lentivirus infection, the body weights, ovarian weights, estrous cycles, reproductive hormones and morphology of the ovary were analysed in rats from different experimental groups. Then to figure out the translational potential of the selective 11ß-HSD1 inhibitor in treating PCOS, PCOS rats were treated with BVT.2733, a selective 11ß-HSD1 inhibitor and a cluster of PCOS-like traits were analysed, including insulin sensitivity, ovulatory function and fertility of rats from the Control, PCOS and PCOS+BVT groups. Rat ovarian explants and human GCs were used to explore the effect of CORT or cortisol on ovarian extracellular matrix remodelling. RESULTS: The elevated expression of 11ß-HSD1 contributed to the increased cortisol and corticosterone (CORT) concentrations observed in the ovaries of PCOS patients and PCOS rats respectively. Our results showed that ovarian overexpression of 11ß-HSD1 induced a cluster of PCOS phenotypes in rats including irregular estrous cycles, reproductive hormone dysfunction and polycystic ovaries. While knockdown of ovarian 11ß-HSD1 of PCOS rats reversed these PCOS-like changes. Additionally, the selective 11ß-HSD1 inhibitor BVT.2733 alleviated PCOS symptoms such as insulin resistance (IR), irregular estrous cycles, reproductive hormone dysfunction, polycystic ovaries, ovulatory dysfunction and subfertility. Moreover, we showed that cortisol target ovarian insulin signalling pathway and ovarian extracellular matrix (ECM) remodelling in vivo, in ovarian explants and in GCs. CONCLUSION: Elevated 11ß-HSD1 abundance in ovarian is involved in the pathogenesis of PCOS by impairing insulin signalling pathway and ECM remodelling. Selective inhibition of 11ß-HSD1 ameliorates a cluster of PCOS phenotypes. Our study demonstrates the selective 11ß-HSD1 inhibitor as a novel and promising strategy for the treatment of PCOS.

Up-regulated FHL2 inhibits ovulation through interacting with androgen receptor and ERK1/2 in polycystic ovary syndrome.

BACKGROUND: The ovulatory dysfunction mechanisms underlying polycystic ovary syndrome (PCOS) are not completely understood. There is no effective therapy for PCOS so far. METHODS: We measured the expression of four and a half LIM domain 2 (FHL2) and other related-genes in human granulosa cells (hGCs) from patients with and without PCOS. To minimise the heterogeneity of patients with PCOS, we only included PCOS patients meeting all three criteria according to the revised Rotterdam consensus. The in vitro effects of FHL2 on ovulatory genes and the underlying mechanisms were examined in KGN cells. The role of FHL2 in ovulation was investigated in vivo by overexpressing FHL2 in rat ovaries via intrabursal lentivirus injection. FINDINGS: Increased FHL2 and androgen receptor (AR) expression and decreased CCAAT/enhancer-binding protein ß (C/EBPß) expression were observed in hGCs from patients with PCOS. FHL2 inhibited the expression of ovulation-related genes, including phosphorylated ERK1/2, C/EBPß, COX2 and HAS2 in KGN cells. It was partially by interacting with AR to act as its co-regulator to inhibit C/EBPß expression and by binding to ERK1/2 to inhibit its phosphorylation. Moreover, FHL2 abundance in hGCs was positively correlated with the basal serum testosterone concentration of patients with PCOS, and dihydrotestosterone (DHT)-induced FHL2 upregulation was mediated by AR signalling in KGN cells. Additionally, lentiviral-mediated functional FHL2 overexpression in rat ovaries for 1 week contributed to an impaired superovulatory response, displaying decreased numbers of retrieved oocytes and a lower MII oocyte rate. 3-week FHL2 overexpression rat models without superovulation led to acyclicity and polycystic ovary morphology. INTERPRETATION: Our findings provide novel insights into the mechanisms underlying the pathogenesis of PCOS, suggesting that FHL2 could be a potential treatment target for ovulatory obstacles in PCOS. FUND: National Key Research and Development Program of China, National Natural Science Foundation, National Institutes of Health project and Shanghai Commission of Science and Technology.