Purpose: Human follicular fluid (FF) is a complex biological fluid that contributes to the micro-environment of oocyte development. The aim of this study was to evaluate the role of steroid and gonadotropic hormones levels and mitochondrial function in embryo development during in vitro fertilization cycles.Methods: This was a cohort study of 138 women receiving IVF/ICSI, including 136 FF samples from 109 infertile women. FF steroid and gonadotropic hormones levels were tested by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and immunoassays. The mRNA expression levels of mitochondrial electron transport chain (ETC) complex genes from FF exosomes were detected by qPCR.Results: Analysis of these individual FF concentrations revealed that LH and FSH concentrations were higher in follicles in which the oocyte developed into a top quality (TQ) blastocyst (LH: 9.44 ± 2.32mIU/ml, FSH: 9.32 ± 1.01mIU/ml) than those in which there was a failure of fertilization (LH: 5.30 ± 0.84mIU/ml, FSH: 6.91 ± 0.62mIU/ml). In contrast, follicular cortisone concentrations were lower for oocytes that resulted in a TQ blastocyst (12.20 ± 0.82mIU/ml). The receiver operating characteristic analysis showed that FF LH and FSH levels predicted TQ blastocyst with excellent AUC value of 0.711 and 0.747. Mitochondrial ETC complex I and III mRNA levels were increased in the FF exosomes of TQ blastocyst. Correlation analysis showed that mRNA levels of ETC complex I was positively correlated with LH and FSH levels in FF.Conclusion: The levels of FF steroid and gonadotropic hormones from single follicle can predetermine subsequent embryo development to some extent. Furthermore, impaired exosome mitochondrial dysfunction is a potiential event that causes hormone change in embryo development.

Polycystic ovary syndrome (PCOS) is widely acknowledged as the prevailing reproductive endocrine disorder accompanied by numerous metabolic dysfunctions. However, there has been a lack of systematic examination regarding the amino acids profile in PCOS. There is a dearth of evidence in regard to the examination of connections between amino acid metabolites found in follicular fluid (FF) and the quality of embryos during in vitro fertilization (IVF). Our objective was to assess amino acid signatures associated with PCOS, as well as identify potential amino acid markers for evaluating embryo quality in PCOS. The cohort study consisted of 143 women who were undergoing lVF/ICSl. Among these, 79 patients who had been diagnosed with PCOS, while the remaining 64 patients did not have PCOS. The concentrations of 30 amino acids present in FF were accurately determined through the use of high-performance liquid chromatography-tandem mass spectrometry. We use the spearman correlation was used to calculate correlations. Odds ratio (ORs) and 95% CIs between differential metabolites and embryo mass were estimated by the logistic regression. The concentrations of glutamine (p = 0.025), taurine (p = 0.017), phenylalanine (p = 0.006), arginine (p = 0.002), histidine (p = 0.001), serine (p = 0.001), Tryptophan (p = 0.037), citrulline (p = 0.05), lysine (p = 0.012), sarcosine (p = 0.028) and 1-Methylhistidine (p = 0.006) in the PCOS group were significantly lower than those in the control group. Both PCOS and control groups showed distinct amino acid profiles between quality subgroups: in PCOS, taurine, aspartic acid, and threonine were higher in the top-quality subgroup, while in controls, alanine, glutamic acid, tyrosine, tryptophan, glycine, ornithine, threonine, and methionine were lower in the poor-quality subgroup. Lower amino acid concentrations were associated with a lower probability of high-quality embryos from IVF. We also identified 11 and 3 amino acids that related to embryo quality in the control and PCOS groups respectively. Our research has the potential to provide valuable insights regarding the involvement of amino acid abnormalities in follicular fluid in the pathophysiology of PCOS. The findings indicated the possibility of variations in amino acid composition, and consequently variations in embryo quality, among normal and PCOS women. Additional research is required in order to substantiate these findings and directly assess the effects on pregnancy and live birth outcomes.

The piwi-interacting RNAs (piRNAs) are essential for controlling transposable elements (TEs) activity in germ cells, yet their expression dynamics and functions during human oogenesis remain poorly understood. Here, we simultaneously profile small and long RNAs in individual human oocytes across four developmental stages. piRNAs, especially PIWIL3-associated short piRNAs, are the predominant small non-coding RNAs during human oogenesis. A marked increase in short-piRNAs coincide with a global reduction of TE expression, particularly LINE-1 and endogenous retroviruses (ERVs). In contrast, PIWIL1- and PIWIL2-associated long piRNAs correlate with the downregulation of certain specific ERV subfamilies. Genomic analyses reveal that highly productive piRNA clusters have evolved asymmetric antisense insertion bias toward LINE-1 and ERVs, enabling TE families-specific regulation. Together, our study provides a valuable single-cell dataset of small and long RNA co-expression landscapes in developing human oocytes and reveals coordinated yet distinct roles of different PIWI/piRNA classes in TE repression during human oogenesis, with short-piRNAs acting as the primary and broad-spectrum suppressors, and long-piRNAs providing coordinated ERV-specific repression.

Male infertility is a global issue caused by poor sperm quality, particularly motility. Enhancement of the sperm quality may improve the fertilization rate in assisted reproductive technology (ART) treatment. Scriptaid, with a novel human sperm motility-stimulating activity, has been investigated as a prospective agent for improving sperm quality and fertilization rate in ART. We evaluated the effects of Scriptaid on asthenozoospermic (AZS) semen, including its impact on motility stimulation and protective effects on cryopreservation and duration of motility, by computer-aided sperm analysis (CASA). Sperm quality improvement by Scriptaid was characterized by increased hyaluronan-binding activity, tyrosine phosphorylation, adenosine triphosphate (ATP) concentration, mitochondrial membrane potential, and an ameliorated AZS fertilization rate in clinical intracytoplasmic sperm injection (ICSI) experiments. Furthermore, our identification of active Scriptaid analogs and different metabolites induced by Scriptaid in spermatozoa lays a solid foundation for the future biomechanical exploration of sperm function. In summary, Scriptaid is a potential candidate for the treatment of male infertility in vitro as it improves sperm quality, prolongs sperm viability, and increases the fertilization rate.

Background Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism and follicular growth arrest. This study investigates the role of a newly identified long non-coding RNA, lncRNA-ZSCAN2-5:15 (HUPCOS), in the dysregulation of androgen metabolism and ovulatory function. Methods Clinical samples from 47 PCOS patients and 68 controls undergoing intracytoplasmic sperm injection were analyzed. Follicular fluid hormone levels and granulosa cell expression of HUPCOS, CYP19 A1, and SMAD4 were measured. A PCOS-like mouse model was established via DHEA injection, and Hupcos overexpression was induced by AAV9, with estrous cycles, hormone levels, and ovarian histology examined. Mechanistic studies in KGN cells included overexpression and knockdown assays, immunoprecipitation, ubiquitination, and dual-luciferase reporter assays. Results PCOS patients showed higher HUPCOS expression (p < 0.01) and testosterone levels (p < 0.0001), and reduced CYP19 A1 in granulosa cells. Hupcos-overexpressing mice showed PCOS-like symptoms, including estrous cycle disturbances and hormonal imbalances. In vitro, HUPCOS overexpression suppressed aromatase expression and estradiol production, while enhancing androstenedione accumulation. Mechanistically, HUPCOS promoted RBPMS ubiquitination, reduced its interaction with SMAD4, and downregulated CYP19 A1 transcription. Co-overexpression of RBPMS and HUPCOS reversed these effects. Conclusions HUPCOS impairs estrogen biosynthesis in PCOS by enhancing RBPMS degradation and disrupting SMAD4-mediated transcription of CYP19 A1. These findings highlight a novel lncRNA-mediated mechanism contributing to hyperandrogenemia and follicular arrest, offering potential targets for PCOS therapy. Graphical Abstract 1. lncRNA HUPCOS is significantly upregulated in granulosa cells of PCOS patients and positively correlates with serum testosterone levels. 2. Overexpression of HUPCOS in mice induces estrous cycle irregularities and PCOS-like ovarian changes. 3. Mechanistically, HUPCOS enhances RBPMS ubiquitination, reducing its interaction with SMAD4 and suppressing CYP19 A1 expression. 4. This HUPCOS-RBPMS-SMAD4 regulatory axis disrupts estrogen biosynthesis and contributes to hyperandrogenism in PCOS.