Follicular Fluid: A Powerful Tool for the Understanding and Diagnosis of Polycystic Ovary Syndrome

The Influence of Ovarian-Derived Extracellular Vesicles in Reproduction

In this chapter, we explore the multifaceted roles of extracellular vesicles (EVs) in ovarian biology, focusing on their contributions to folliculogenesis, oocyte competence, corpus luteum function, and immune response regulation. EVs, particularly those derived from follicular fluid (ffEVs), are crucial mediators of cell-to-cell communication within the ovarian follicle, influencing processes such as meiotic progression, stress response, and hormonal regulation. We review preexisting literature, highlighting key findings on the molecular cargo of EVs, such as miRNAs and proteins, and their involvement in regulating the function of the follicle cells. Additionally, the influence of EVs on the immune responses within the ovary was also addressed. Some attention is given to the potential of EVs as non-invasive biomarkers and therapeutic tools, particularly in addressing conditions like premature ovarian insufficiency and polycystic ovary syndrome. By discussing the existing challenges and emerging research, we hope that this chapter will provide a deeper understanding of EVs' therapeutic potential and offer insights or suggestions for advancing assisted reproductive technologies.

Insight into metabolic dysregulation of polycystic ovary syndrome utilizing metabolomic signatures: a narrative review

Polycystic ovary syndrome (PCOS) is a complex multifactorial endocrinopathy affecting reproductive aged women globally, whose presentation is strongly influenced by genetic makeup, ethnic, and geographic diversity leaving these affected women substantially predisposed to reproductive and metabolic perturbations. Sophisticated techniques spanning genomics, proteomics, epigenomics, and transcriptomics have been harnessed to comprehensively understand the enigmatic pathophysiology of PCOS, however, conclusive markers for PCOS are still lacking today. Metabolomics represents a paradigm shift in biotechnological advances enabling the simultaneous identification and quantification of metabolites and the use of this approach has added yet another dimension to help unravel the strong metabolic component of PCOS. Reports dissecting the metabolic signature of PCOS have revealed disparate levels of metabolites such as pyruvate, lactate, triglycerides, free fatty acids, carnitines, branched chain and essential amino acids, and steroid intermediates in major biological compartments. These metabolites have been shown to be altered in women with PCOS overall, after phenotypic subgrouping, in animal models of PCOS, and also following therapeutic intervention. This review seeks to supplement previous reviews by highlighting the aforementioned aspects and to provide easy, coherent and elementary access to significant findings and emerging trends. This will in turn help to delineate the metabolic plot in women with PCOS in various biological compartments including plasma, urine, follicular microenvironment, and gut. This may pave the way to design additional studies on the quest of unraveling the etiology of PCOS and delving into novel biomarkers for its diagnosis, prognosis and management.

Unraveling the complexity of follicular fluid: insights into its composition, function, and clinical implications

Follicular fluid (FF) plays a vital role in the bidirectional communication between oocytes and granulosa cells (GCs), regulating and promoting oocyte growth and development. This fluid constitutes a complex microenvironment, rich in various molecules including hormones, growth factors, cytokines, lipids, proteins, and extracellular vesicles. Understanding the composition and metabolic profile of follicular fluid is important for investigating ovarian pathologies such as polycystic ovary syndrome (PCOS) and endometriosis. Additionally, analyzing follicular fluid can offer valuable insights into oocyte quality, aiding in optimal oocyte selection for in vitro fertilization (IVF). This review provides an overview of follicular fluid composition, classification of its components and discusses the influential components of oocyte development. It also highlights the role of follicular fluid in the pathogenesis and diagnosis of ovarian diseases, along with potential follicular fluid biomarkers for assessing oocyte quality. By understanding the intricate relationship between follicular fluid and oocyte development, we can advance fertility research and improve clinical outcomes for infertility patients.

Proteomic Analysis of Follicular Fluid in Polycystic Ovary Syndrome: Insights into Protein Composition and Metabolic Pathway Alterations

This study explores the proteomic composition of follicular fluid (FF) from women undergoing oocyte retrieval for in vitro fertilisation (IVF), with a focus on the effects of polycystic ovary syndrome (PCOS). FF samples were collected from 74 patients, including 34 with PCOS and 40 oocyte donors. Proteomic profiling using machine learning identified significant differences in protein abundance between the PCOS and control groups. Of the 484 quantified proteins, 20 showed significantly altered levels in the PCOS group. Functional annotation and pathway enrichment analysis pointed to the involvement of protease inhibitors and immune-related proteins in the pathophysiology of PCOS, suggesting that inflammation and immune dysregulation may play a key role. Additionally, HDL assembly was identified as a significant pathway, with apolipoprotein-AI (APOA1) and alpha-2-macroglobulin (A2M) as the major proteins involved. Notably, myosin light polypeptide 6 was the most downregulated protein, showing the highest absolute fold change, and may serve as a novel independent biomarker for PCOS.

Which is the current knowledge on man-made endocrine- disrupting chemicals in follicular fluid? An overview of effects on ovarian function and reproductive health

The increase in female reproductive disorders, such as polycystic ovary syndrome, endometriosis, and diminished ovarian reserve that lead to subfertility and infertility, has encouraged researchers to search and discover their underlying causes and risk factors. One of the crucial factors that may influence the increasing number of reproductive issues is environmental pollution, particularly exposure to man-made endocrine-disrupting chemicals (EDCs). EDCs can interfere with the ovarian microenvironment, impacting not only granulosa cell function but also other surrounding ovarian cells and follicular fluid (FF), which all play essential roles for oocyte development, maturation, and overall reproductive function. FF surrounds developing oocytes within an ovarian follicle and represents a dynamic milieu. EDCs are usually found in biological fluids, and FF is therefore of interest in this respect. This narrative review examines the current knowledge on specific classes of EDCs, including industrial chemicals, pesticides, and plasticizers, and their known effects on hormonal signaling pathways, gene expression, mitochondrial function, oxidative stress induction, and inflammation in FF. We describe the impact of EDCs on the development of reproductive disorders, oocyte quality, menstrual cycle regulation, and their effect on assisted reproductive technique outcomes. The potential transgenerational effects of EDCs on offspring through animal and first-human studies has been considered also. While significant progress has been made, the current understanding of EDCs' effects on ovarian function, particularly in humans, remains limited, underscoring the need for further research to clarify actions and effects of EDCs in the ovary.

Astaxanthin treatment decreases pro-inflammatory cytokines and improves reproductive outcomes in patients with polycystic ovary syndrome undergoing assisted reproductive technology: A randomized clinical trial

RESEARCH QUESTION

In a randomized, triple-blind, placebo-controlled clinical trial (RCT), we investigated the effect of astaxanthin (AST) on pro-inflammatory cytokines, oxidative stress (OS) markers, and assisted reproductive technology (ART) outcomes in 44 infertile Polycystic Ovary Syndrome (PCOS) patients.

DESIGN

Patients with PCOS were randomly divided into two groups. The intervention group received 6 mg AST, and the control group received placebo daily for 8 weeks. Blood samples were obtained from all patients before and after intervention and follicular fluid (FF) was collected during the ART procedure. Interleukin (IL) -6, IL-1β were evaluated from serum samples and FF and OS markers (malondialdehyde [MDA], catalase [CAT], superoxide dismutase [SOD], and reactive oxygen species [ROS]) were measured from FF. The groups were compared for ART outcomes as well.

RESULTS

A significant decrease in IL-6 and IL-1β concentrations (both, P = < 0.01) serum levels was found following AST treatment. FF cytokine levels and OS markers did not differ significantly between the groups. Reproductive outcomes, including the number of oocytes retrieved (P = 0.01), the MII oocyte count (P = 0.007), oocyte maturity rate (MII %) (P = 0.02) and number of frozen embryos (P = 0.03) significantly improved after intervention. No significant differences were found in chemical, clinical and multiple pregnancies between the groups.

CONCLUSIONS

AST pretreatment may modify inflammation and improve ART outcomes in PCOS infertile patients. Further investigations are recommended to verify these findings.

Metformin augments major cytoplasmic organization except for spindle organization in oocytes cultured under hyperglycemic and hyperlipidemic conditions: An in vitro study

The present study aimed to investigate the role of antidiabetic drug metformin on the cytoplasmic organization of oocytes. Germinal vesicle (GV) stage oocytes were collected from adult female Swiss albino mice and subjected to in vitro maturation (IVM) in various experimental groups- control, vehicle control (0.3% ethanol), metformin (50 μg/mL), high glucose and high lipid (HGHL, 10 mM glucose; 150 μM palmitic acid; 75 μM stearic acid and 200 μM oleic acid in ethanol), and HGHL supplemented with metformin. The metaphase II (MII) oocytes were analyzed for lipid accumulation, mitochondrial and endoplasmic reticulum (ER) distribution pattern, oxidative and ER stress, actin filament organization, cortical granule distribution pattern, spindle organization and chromosome alignment. An early polar body extrusion was observed in the HGHL group. However, the maturation rate at 24 h did not differ significantly among the experimental groups compared to the control. The HGHL conditions exhibited significantly higher levels of oxidative stress, ER stress, poor actin filament organization, increased lipid accumulation, altered mitochondrial distribution, spindle abnormalities, and chromosome misalignment compared to the control. Except for spindle organization, supplementation of metformin to the HGHL conditions improved all the parameters (non-significant for ER and actin distribution pattern). These results show that metformin exposure in the culture media helped to improve the hyperglycemia and hyperlipidemia-induced cytoplasmic anomalies except for spindle organization. Given the crucial role of spindle organization in proper chromosome segregation during oocyte maturation and meiotic resumption, the implications of metformin's limitations in this aspect warrant careful evaluation and further investigation.

Follicular Fluid and Blood Monitorization of Infertility Biomarkers in Women with Endometriosis

Infertility is recognized globally as a social disease and a growing medical condition, posing a significant challenge to modern reproductive health. Endometriosis, the third-most frequent gynecologic disorder, is one of the most common and intricate conditions that can lead to female infertility. Despite extensive research, the etiology, malignant transformation, and biological therapy of endometriosis remain unknown. Blood and follicular fluid are two matrices that have been carefully studied and can provide insights into women's health. These matrices are clinically significant because they contain metabolites closely associated with women's illness stage and reproductive outcomes. Nowadays, the application of metabolomic analysis in biological matrices may be able to predict the outcome of assisted reproductive technologies with greater precision. From a molecular viewpoint on reproductive health, we evaluate and compare the utilization of human follicular fluid and blood as matrices in analysis for diagnostic and assisted reproductive technology (ART) predictors of success for endometriosis patients. In the follicular fluid (FF), plasma, and serum of endometriosis-affected women, researchers identified dysregulations of oxidative stress, upregulation of several immune factors, and aberrations in energy metabolic pathways. The altered signatures negatively correlate with the overall oocyte and embryo quality and fertilization rate.

Metabolic signature of follicular fluid in infertility-related diseases: a narrative review

Metabolomics offers new methods to identify biomarkers for oocyte and embryo quality, and for a better understanding of the physiopathology of infertility. This review investigated the latest findings regarding metabolome-derived biomarkers in follicular fluid of women with the most common types of infertility, and the potential impact on reproductive medicine outcomes. PubMed was searched for publications on metabolomics and human follicular fluid, and key biomarkers, kinetics and relationships with infertility diseases were identified. A reduced concentration of glucose and increased concentrations of lactate and pyruvate were found in follicular fluid of patients with endometriosis and diminished ovarian reserve, and the opposite was found in patients with polycystic ovary syndrome. These signatures may lead to the hypothesis of changed metabolite concentrations in patients with endometriosis and diminished ovarian reserve, and a metabolic pathway alteration with decreased aerobic glycolysis in patients with polycystic ovary syndrome. However, the pattern found in patients with endometriosis and low responders may also be expected in follicular fluid of fertile women. Larger studies are needed to confirm the results. An international database may help to highlight follicular fluid biomarkers in order to improve the selection of cryopreserved oocytes, and to enrich culture medium to restore normal metabolism and improve reproductive treatment outcomes.

Association Between Exposure to Multiple Toxic Metals in Follicular Fluid and the Risk of PCOS Among Infertile Women: The Mediating Effect of Metabolic Markers

Polycystic ovary syndrome (PCOS) severely affects women's fertility and accompanies serious metabolic disturbances, affecting 5%-20% of women of reproductive age globally. We previously found that exposure to toxic metals in the blood raised the risk of PCOS, but the association between exposure to toxic metals and the risk of PCOS in the follicular fluid, the microenvironment for oocyte growth and development in females, and its effect on metabolism has not been reported. This study aimed to evaluate the associations between the concentrations of cadmium (Cd), mercury (Hg), barium (Ba) and arsenic (As) in FF and the risk of PCOS, and to explore the mediating effect of metabolic markers in FF on the above relationship. We conducted a case-control study, including 557 women with PCOS and 651 controls. Ba, Cd, Hg and As levels in FF were measured by ICP-MS, metabolites levels in FF was measured by LC-MS/MS among 168 participants randomly selected from all the participants. Logistic regression models were used to assess the association of a single metal level with the PCOS risk, and linear regression models were used to assess the relationships of a single metal level with clinical phenotype parameters and metabolites levels. Combined effect of metals mixture levels on the risk of PCOS were assessed via weighted quantile sum (WQS) regression and bayesian kernel machine regression (BKMR). Medication analysis was performed to explore the role of metabolic markers on the relationship of toxic metals levels with the risk of PCOS. The exposure levels of Cd, Hg, Ba and As in FF were all positively and significantly associated with the PCOS risk (with respect to the highest vs. lowest tertile group: OR = 1.57, 95% CI = 1.17 ~ 2.12 for Cd, OR = 1.69, 95% CI = 1.22 ~ 2.34 for Hg, OR = 1.76, 95% CI = 1.32 ~ 2.34 for Ba, OR = 1.42, 95% CI = 1.05 ~ 1.91 for As). In addition, levels of metal mixture also significantly correlated with the risk of PCOS, Cd level contributed most to it. Moreover, we observed significant positive relationships between Cd level and LH (β = 0.048, 95% CI = 0.002 ~ 0.094), T (β = 0.077, 95% CI = 0.029 ~ 0.125) and HOMA-IR value (β = 0.060, 95% CI = 0.012 ~ 0.107), as well as Hg level with LH, FSH/LH ratio and TC. Furthermore, we revealed that estrone sulfate, LysoPE 22:6 and N-Undecanoylglycine were significantly and positively mediating the association between Cd level and the risk of PCOS (with mediated proportion of 0.39, 0.24 and 0.35, respectively), and between Hg level and the risk of PCOS (with mediated proportion of 0.29, 0.20 and 0.46, respectively). These highly expressed metabolites significantly enriched in the fatty acid oxidation, steroid hormone biosynthesis and glycerophospholipids metabolism, which may explain the reason why the levels of Cd and Hg in FF associated with the phenotype of PCOS. Ba and As in FF was not found the above phenomenon. Our results suggested that exposure to multiple toxic metals (Cd, Hg, Ba and As) in FF associated with the increased risk of PCOS, Cd was a major contributor. Levels of Cd and Hg in FF significantly associated with the phenotype of PCOS. The above association may result from that Cd and Hg in FF related with the disturbance of fatty acid oxidation, steroid hormone biosynthesis and the glycerophospholipids metabolism.

Increased Vasoactive Intestinal Peptide (VIP) in polycystic ovary syndrome patients undergoing IVF

Introduction

Polycystic ovary syndrome (PCOS) is a common multifactorial and polygenic disorder of the endocrine system, affecting up to 20% of women in reproductive age with a still unknown etiology. Follicular fluid (FF) represents an environment for the normal development of follicles rich in metabolites, hormones and neurotransmitters, but in some instances of PCOS the composition can be different. Vasoactive intestinal peptide (VIP) is an endogenous autonomic neuropeptide involved in follicular atresia, granulosa cell physiology and steroidogenesis.

Methods

ELISA assays were performed to measure VIP and estradiol levels in human follicular fluids, while AMH, FSH, LH, estradiol and progesterone in the plasma were quantified by chemiluminescence. UHPLC/QTOF was used to perform the untargeted metabolomic analysis.

Results

Our ELISA and metabolomic results show: i) an increased concentration of VIP in follicular fluid of PCOS patients (n=9) of about 30% with respect to control group (n=10) (132 ± 28 pg/ml versus 103 ± 26 pg/ml, p=0,03) in women undergoing in vitro fertilization (IVF), ii) a linear positive correlation (p=0.05, r=0.45) between VIP concentration and serum Anti-Müllerian Hormone (AMH) concentration and iii) a linear negative correlation between VIP and noradrenaline metabolism. No correlation between VIP and estradiol (E2) concentration in follicular fluid was found. A negative correlation was found between VIP and noradrenaline metabolite 3,4-dihydroxyphenylglycolaldehyde (DOPGAL) in follicular fluids.

Conclusion

VIP concentration in follicular fluids was increased in PCOS patients and a correlation was found with noradrenaline metabolism indicating a possible dysregulation of the sympathetic reflex in the ovarian follicles. The functional role of VIP as noradrenergic modulator in ovarian physiology and PCOS pathophysiology was discussed.

The Role of One-Carbon Metabolism and Methyl Donors in Medically Assisted Reproduction: A Narrative Review of the Literature

One-carbon (1-C) metabolic deficiency impairs homeostasis, driving disease development, including infertility. It is of importance to summarize the current evidence regarding the clinical utility of 1-C metabolism-related biomolecules and methyl donors, namely, folate, betaine, choline, vitamin B12, homocysteine (Hcy), and zinc, as potential biomarkers, dietary supplements, and culture media supplements in the context of medically assisted reproduction (MAR). A narrative review of the literature was conducted in the PubMed/Medline database. Diet, ageing, and the endocrine milieu of individuals affect both 1-C metabolism and fertility status. In vitro fertilization (IVF) techniques, and culture conditions in particular, have a direct impact on 1-C metabolic activity in gametes and embryos. Critical analysis indicated that zinc supplementation in cryopreservation media may be a promising approach to reducing oxidative damage, while female serum homocysteine levels may be employed as a possible biomarker for predicting IVF outcomes. Nonetheless, the level of evidence is low, and future studies are needed to verify these data. One-carbon metabolism-related processes, including redox defense and epigenetic regulation, may be compromised in IVF-derived embryos. The study of 1-C metabolism may lead the way towards improving MAR efficiency and safety and ensuring the lifelong health of MAR infants.

Follicular Fluid Proteomic Analysis of Women Undergoing Assisted Reproduction Suggests That Apolipoprotein A1 Is a Potential Fertility Marker

Infertility affects millions worldwide, posing a significant global health challenge. The proteomic analysis of follicular fluid provides a comprehensive view of the complex molecular landscape within ovarian follicles, offering valuable information on the factors influencing oocyte development and on the overall reproductive health. The follicular fluid is derived from the plasma and contains various proteins that can have different roles in oocyte health and infertility, and this fluid is a critical microenvironment for the developing oocytes as well. Using the high-performance liquid chromatography-mass spectrometry method, we investigated the protein composition of the follicular fluid, and after classification, we carried out relative quantification of the identified proteins in the pregnant (P) and non-pregnant (NP) groups. Based on the protein-protein interaction analysis, albumin and apolipoprotein A1 (ApoA1) were found to be hub proteins, and the quantitative comparison of the P and NP groups resulted in a significantly lower concentration of ApoA1 and high-density lipoprotein cholesterol in the P group. As both molecules are involved in the cholesterol transport, we also investigated their role in the development of oocytes and in the prediction of fertility.

Biomarkers in Polycystic Ovary Syndrome

Polycystic Ovary Syndrome (PCOS) is the most common endocrine disorder in reproductive-age women. PCOS is diagnosed by the presence of two of the following three characteristics: hyperandrogenemia and/or hyperandrogenism, oligo/amenorrhea, and polycystic ovarian morphology. PCOS is associated with reproductive and non-reproductive complications, including obesity, insulin resistance and diabetes, dyslipidemia, and increased blood pressure. There is an urgent need for biomarkers that address both the reproductive and non-reproductive aspects of this complex syndrome. This review focuses on biomarkers, or potential ones, associated with the reproductive and non-reproductive aspects of PCOS, including anthropometric and clinical biomarkers, insulin and the IGF-1 system, lipids, anti-Müllerian hormone and gonadotropins, steroids, inflammatory and renal injury biomarkers, oxidative stress, and non-coding RNAs. We expect that this review will bring some light on the recent updates in the field and encourage researchers to join the exciting and promising field of PCOS biomarkers.

Protein Expression and Bioinformatics Study of Granulosa Cells of Polycystic Ovary Syndrome Expressed Under the Influence of DHEA

Background

The reproductive system is heavily dependent on ovarian follicles, which are made up of germ cells (oocytes) and granulosa cells (GCs), including cumulus granulosa cells (CGCs) and mural granulosa cells (MGCs). Understanding their normal and steroid-induced functions is the key to understanding the pathophysiology of endocrinal diseases in women.

Objective

This study investigated the differentially expressed proteins by CGCs and MGCs of patients with polycystic ovarian syndrome (PCOS) and without subsequent exposure to dehydroepiandrosterone sulfate (DHEAS) and functional differentiation.

Design

The present study was observational and experimental study carried out in hospital involving 80 female patients undergoing IVF for infertility.

Methods

In this study, we isolated CGCs and MGCs from the follicular fluid of both PCOS and non-PCOS patients undergoing in vitro fertilization (IVF). The cells were cultured and treated with DHEAS for 48 hours, and these cells were extracted, digested, and analyzed by tandem mass spectrometry followed by processing of the results using open-source bioinformatics tools.

Results

The present investigation discovered 276 and 341 proteins in CGCs and MGCs, respectively. DHEAS reduced the number of proteins expressed by CGCs and MGCs to 34 and 57 from 91 and 94, respectively. Venn results of CGCs revealed 49, 53, 36, and 21 proteins in normal CGCs, PCOS-CGCs, post-DHEAS, and PCOS-CGCs, respectively. Venn analysis of MGCs showed 51 proteins specific to PCOS and 29 shared by normal and PCOS samples after DHEAS therapy. MGCs express the most binding and catalytic proteins, whereas CGCs express transporter-related proteins. A protein pathway study demonstrated considerable differences between normal and PCOS samples, while DHEAS-treated samples of both cell lines showed distinct pathways. String findings identified important network route components such as albumin, actin, apolipoprotein, complement component C3, and heat shock protein.

Conclusion

This is the first study to show how DHEAS-induced stress affects the expression of proteins by MGCs and CGCs isolated from normal and PCOS patients. Further studies are recommended to identify PCOS biomarkers from CGCs and MGCs expressed under the influence of DHEAS.

Follicular Fluid-Derived Small Extracellular Vesicles Alleviate DHEA-Induced Granulosa Cell Apoptosis by Delivering LINC00092

Polycystic ovary syndrome (PCOS) is a perplexing condition in females of reproductive age. Dysplasia of ovarian granulosa cell (GC) is implicated in PCOS. Follicular fluid (FF)-extracellular vesicles (Evs) are important in cell-cell communication during follicular development. The current study elaborated on the function and mechanism of FF-Evs in the viability and apoptosis of GC cells in PCOS development. Human GC cells KGN were treated with dehydroepiandrosterone (DHEA) to mimic a PCOS-like condition in vitro, which were further co-cultured with the FF-derived Evs (FF-Evs). The FF-Evs treatment significantly reduced DHEA-induced apoptosis of KGN cells while promoting cell viability and migration. The lncRNA microarray analysis showed that FF-Evs mainly deliver LINC00092 into the KGN cells. Knockdown of LINC00092 negated the protective effect of FF-Evs against DHEA-induced damage on KGN cells. Moreover, by performing bioinformatics analyses and biotin-labeled RNA pull-down assay, we found that LINC00092 could bind to the RNA binding protein LIN28B and inhibit its binding to pre-microRNA-18-5p, which allowed biogenesis of pre-miR-18-5p and increased the expression of miR-18b-5p, a miRNA with known alleviating role in PCOS by suppressing the PTEN mRNA. Collectively, the present work demonstrates that FF-Evs can alleviate DHEA-induced GC damage by delivering LINC00092.

Elevated follicular cortisone level is a negative predictor of clinical pregnancy in women undergoing fresh embryo transfer

Background

Although numerous studies have investigated the potential correlation between follicular fluid (FF) steroid concentrations and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes, few have accounted for the effect of controlled ovarian hyperstimulation regimes on FF steroid concentrations.

Objective

To comprehensively compare follicular steroid concentrations between women stimulated with gonadotropin-releasing hormone agonist (GnRHa) and antagonist (GnRHant) protocols and to explore the associations between FF steroid concentrations and IVF/ICSI outcomes.

Methods

A total of 295 infertile women undergoing IVF/ICSI from January 2018 to May 2020 were enrolled. Eighty-four and 211 women received GnRHa and GnRHant protocols, respectively. Seventeen steroids in FF were quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS), and the correlation of follicular steroids with clinical pregnancy was explored.

Results

Follicular steroid concentrations were similar between the GnRHa and GnRHant groups. Follicular cortisone levels were adversely associated with clinical pregnancy in fresh embryo transfers. Receiver operating characteristic (ROC) analysis revealed an area under the ROC curve (AUC) of 0.639 (95% confidence interval = 0.527-0.751, p = 0.025) for predicting non-pregnancy, with an optimal cutoff value of 15.81 ng/mL (sensitivity = 33.3%, specificity = 94.1%). Women with FF cortisone concentrations ≥15.81 ng/mL were fifty times less likely to achieve clinical pregnancy in fresh embryo transfers than those with FF cortisone levels below this threshold (adjusted OR = 0.019, 95% confidence interval = 0.002-0.207, p = 0.001) after adjusting for age, body mass index, baseline serum progesterone levels, serum levels of luteinizing hormone, estradiol and progesterone on human chorionic gonadotropin day, ovarian stimulation protocols, and the number of transferred embryos.

Conclusions

There was no significant difference in intrafollicular steroid levels between GnRHa and GnRHant protocols, and intrafollicular cortisone level ≥15.81 ng/mL was found to be a strong negative predictor of clinical pregnancy in fresh embryo transfers with high specificity.

Bilirubin Concentration in Follicular Fluid Is Increased in Infertile Females, Correlates with Decreased Antioxidant Levels and Increased Nitric Oxide Metabolites, and Negatively Affects Outcome Measures of In Vitro Fertilization

In a previous study, we showed that various low-molecular-weight compounds in follicular fluid (FF) samples of control fertile females (CFF) have different concentrations compared to those found in FF of infertile females (IF), before and after their categorization into different subgroups, according to their clinical diagnosis of infertility. Using the same FF samples of this previous study, we here analyzed the FF concentrations of free and bound bilirubin and compared the results obtained in CFF, IF and the different subgroups of IF (endometriosis, EM, polycystic ovary syndrome, PCOS, age-related reduced ovarian reserve, AR-ROR, reduced ovarian reserve, ROR, genetic infertility, GI and unexplained infertility, UI). The results clearly indicated that CFF had lower values of free, bound and total bilirubin compared to the respective values measured in pooled IF. These differences were observed even when IF were categorized into EM, PCOS, AR-ROR, ROR, GI and UI, with EM and PCOS showing the highest values of free, bound and total bilirubin among the six subgroups. Using previous results of ascorbic acid, GSH and nitrite + nitrate measured in the same FF samples of the same FF donors, we found that total bilirubin in FF increased as a function of decreased values of ascorbic acid and GSH, and increased concentrations of nitrite + nitrate. The values of total bilirubin negatively correlated with the clinical parameters of fertilization procedures (number of retrieved oocytes, mature oocytes, fertilized oocytes, blastocysts, high-quality blastocysts) and with clinical pregnancies and birth rates. Bilirubin concentrations in FF were not linked to those found in serum samples of FF donors, thereby strongly suggesting that its over production was due to higher activity of heme oxygenase-1 (HO-1), the key enzyme responsible for bilirubin formation, in granulosa cells, or cumulus cells or oocytes of IF and ultimately leading to bilirubin accumulation in FF. Since increased activity of HO-1 is one of the main enzymatic intracellular mechanisms of defense towards external insults (oxidative/nitrosative stress, inflammation), and since we found correlations among bilirubin and oxidative/nitrosative stress in these FF samples, it may reasonably be supposed that bilirubin increase in FF of IF is the result of protracted exposures to the aforementioned insults evidently playing relevant roles in female infertility.

Porcine Follicular Fluid-Derived Exosome: The Pivotal Material for Porcine Oocyte Maturation in Lipid Antioxidant Activity

Several studies have examined exosomes derived from porcine follicular fluid (FF), but few have reported their application in controlled experiments. The main concern in the field of embryology may be that controlled conditions, such as using a defined medium intermittently, cause poor results in mammalian oocyte maturation and embryo development. The first reason is the absence of the FF, which copes with the majority of the processes emerging in oocytes and embryos. Therefore, we added exosomes derived from porcine FF to the maturation medium of porcine oocytes. For morphological assessment, cumulus cell expansion and subsequent embryonic development were evaluated. Moreover, several stainings, such as glutathione (GSH) and reactive oxygen species (ROS), fatty acid, ATP, and mitochondrial activity, as well as evaluations of gene expression and protein analysis, were used for the functional verification of exosomes. When the oocytes were treated with exosomes, the lipid metabolism and cell survival of the oocytes were fully recovered, as well as morphological evaluations compared to the porcine FF-excluded defined medium. Therefore, controlled experiments may produce reliable data if the exosomes are treated with the desired amounts, and we suggest applying FF-derived exosomes to promote experimental data when performing controlled experiments in embryology.

Dysregulation of steroid metabolome in follicular fluid links phthalate exposure to diminished ovarian reserve of childbearing-age women

The widespread use of phthalates (PAEs) has drawn increasing attention due to their endocrine disruption and reproductive toxicity, while the steroid metabolome is essential for follicular development. However, the mechanism by which PAE exposure affects ovarian reserve through the steroid metabolome remains unclear. This study recruited 264 childbearing-age women in Tianjin (China) from April 2019 to August 2020 in a cross-sectional design. Target metabolome analysis of 16 steroids was performed in follicular fluid (FF) to compare diminished ovarian reserve (DOR) against normal ovarian reserve (NOR) women and differential steroids were identified using binary logistic analyses. Further analysis of eleven PAE metabolites (mPAEs) in FF was conducted, and the retrieved oocyte number (RON) representing ovarian reserve was counted. Multiple linear regression and quantile-based g-computation (qgcomp) models were used to associate individual mPAEs and mPAE mixture with the DOR-related differential steroids in FF. Mediation analysis was used to discuss the mediating effect of DOR-related steroids on the association between mPAEs and RON. Androstenedione (A4), corticosterone (CORT), cortisol (COR) and cortisone were significantly down-regulated in FF from women with DOR. Nine mPAEs with detection frequencies greater than 60% and median concentrations of 0.02-4.86 ng/mL were incorporated into statistical models. Negative associations with COR and CORT were found for mono-ethyl phthalate (mEP), mono-(2-ethyl-5-oxohexyl) phthalate (mEOHP), and mono-2-ethylhexyl phthalate (mEHP). A positive association with cortisone was found for mEOHP, mEHP, monobutyl phthalate (mBP), and mono (2-isobutyl) phthalate (miBP). The qgcomp and mediation analyses revealed that mEP and mEOHP not only significantly contributed to the decline of COR and CORT in the mixed exposure but also indirectly reduced RON through the mediating effects of COR and CORT. In conclusion, PAE exposure may decrease ovarian reserve by downregulating COR and CORT.

A Pilot Study on Biochemical Profile of Follicular Fluid in Breast Cancer Patients

Breast cancer (BC) is the most common type of cancer among women in almost all countries worldwide and is one of the oncological pathologies for which is indicated fertility preservation, a type of procedure used to help keep a person's ability to have children. Follicular fluid (FF) is a major component of oocyte microenvironment, which is involved in oocyte growth, follicular maturation, and in communication between germ and somatic cells; furthermore, it accumulates all metabolites during oocytes growth. To obtain information about changes on fertility due to cancer, we aimed at investigating potential biomarkers to discriminate between FF samples obtained from 16 BC patients and 10 healthy women undergoing in vitro fertilization treatments. An NMR-based metabolomics approach was performed to investigate the FF metabolic profiles; ELISA and western blotting assays were used to investigate protein markers of oxidative and inflammatory stress, which are processes closely related to cancer. Our results seem to suggest that FFs of BC women display some significant metabolic alterations in comparison to healthy controls, and these variations are also related with tumor staging.

Gonadotropins as pharmacological agents in assisted reproductive technology and polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex endocrinopathy associated with subfertility/infertility and pregnancy complications. Most PCOS women opt for assisted reproductive technologies (ART) for successful conception; however, optimization of the relative doses of the gonadotropins [follicle-stimulating hormone (FSH), luteinizing hormone (LH)/human chorionic gonadotropin (hCG)] for appropriate steroidogenesis, without causing ovarian hyperstimulatory syndrome (OHSS), is challenging. Embryonic factors probably do not contribute to pregnancy loss in PCOS women, albeit hormonal imbalance impairs the metabolic microenvironment critical for oocyte maturation and endometrial receptivity. Certain clinical studies have confirmed the role of metabolic corrections in increasing the rate of pregnancy in PCOS women. This review focuses on the impact of untimely high LHCGR and/or LH levels on oocyte/embryo quality, pregnancy outcomes in ART, and exploring LHCGR as a potential drug target in PCOS women.

Diagnosis values of three-dimensional power Doppler ultrasonography in polycystic ovary syndrome and its relationship with serum sex hormone levels

BACKGROUND

The diagnosis of polycystic ovary syndrome (PCOS) is of great significance for early detection, timely standardized treatment and prevention of long-term complications. This study aimed to observe and measure the intraovarian blood flow distribution and blood flow indexes in patients with PCOS by three-dimensional power Doppler ultrasonography, and to evaluate its diagnostic value for PCOS and its correlation with serum sex hormone levels.

EXPERIMENTAL DESIGN

Patients who were diagnosed with PCOS and met the inclusion and exclusion criteria were recruited as the PCOS group, and 85 age-matched healthy women were arranged in healthy control (HC) group. Participants underwent three-dimensional power Doppler ultrasound. Serum sex hormone was analyzed by chemiluminescence. The diagnostic value was analyzed by relative operating characteristic (ROC) analysis. Spearman correlation coefficient analysis was applied to determine the correlation of vascularization index with serum sex hormone levels.

RESULTS

The vascularization index (VI), flow index (FI), and vascularization flow index (VFI) values in PCOS patients were all statistically higher than those of HC. The combined index (0.445 * VI + 0.1 * FI + 1.057 * VFI) has a higher diagnostic value of PCOS compared with the three indexes alone.

CONCLUSION

Three-dimensional power Doppler ultrasound could observe and quantitatively evaluate the distribution of blood flow in the ovary, which has a high diagnostic value and might provide a reference in clinical use.

Intrafollicular fluid metabolic abnormalities in relation to ovarian hyperstimulation syndrome: Follicular fluid metabolomics via gas chromatography-mass spectrometry

INTRODUCTION

Ovarian hyperstimulation syndrome (OHSS) is the most serious iatrogenic complication of ovulation stimulation during assisted reproductive technology. The main objective of this study was to investigate intrafollicular fluid metabolic change profiles of OHSS in non-ovarian etiologic infertility women (CON) and polycystic ovarian syndrome patients (PCOS).

METHODS

87 infertile women were divided into four subgroups: CON-Norm (CON with normal ovarian response), CON-OHSS (CON with OHSS), PCOS-Norm (PCOS with normal ovarian response), and PCOS-OHSS (PCOS with OHSS). The intrafollicular fluid metabolic profiles were analyzed with gas chromatography-mass spectrometry. The multivariable-adjusted conditional logistic regression was applied to assess the association of metabolites with OHSS risk.

RESULTS

We identified 17 and 3 metabolites that related to OHSS risk in CON and PCOS, respectively. 13 OHSS risk-related metabolites in CON were unsaturated fatty acids, 8 of which were also the significantly altered metabolites between all PCOS and CON-Norm.

CONCLUSION

Our study may shed light on the role of intrafollicular fluid metabolic abnormalities in the pathophysiology of OHSS. The findings suggested that there might be some metabolic heterogeneities underlying the development of OHSS in CON and PCOS women and indicated possible shared etiological factors in the development of PCOS and OHSS.

Role of pyroglutamic acid in cumulus cells of women with polycystic ovary syndrome

PURPOSE

Polycystic ovary syndrome is a complex heterogeneous endocrine disorder associated with established metabolic abnormalities and is a common cause of infertility in females. Glutathione metabolism in the cumulus cells (CCs) of women with PCOS may be correlated to the quality of oocytes for infertility treatment; therefore, we used a metabolomics approach to examine changes in CCs from women with PCOS and oocyte quality.

METHODS

Among 135 women undergoing fertility treatment in the present study, there were 43 women with PCOS and 92 without. CCs were collected from the two groups and levels of pyroglutamic acid were measured using LC-MS/MS followed by qPCR and Western blot analysis to examine genes and proteins involved in pyroglutamic acid metabolism related to glutathione synthesis.

RESULTS

Women with PCOS showed increased levels of L-pyroglutamic acid, L-glutamate, and L-phenylalanine and decreased levels of Cys-Gly and N-acetyl-L-methionine. Gene expression of OPLAH, involved in pyroglutamic synthesis, was significantly increased in women with PCOS compared with those without. Gene expression of GSS was significantly decreased in women with PCOS and synthesis of glutathione synthetase protein was decreased. Expression of nuclear factor erythroid 2-related factor 2, involved in resistance to oxidative stress, was significantly increased in women with PCOS.

CONCLUSIONS

CCs of women with PCOS showed high concentrations of pyroglutamic acid and reduced glutathione synthesis, which causes oxidative stress in CCs, suggesting that decreased glutathione synthesis due to high levels of pyroglutamic acid in CCs may be related to the quality of oocytes in women with PCOS.

Global Transcriptional Profiling of Granulosa Cells from Polycystic Ovary Syndrome Patients: Comparative Analyses of Patients with or without History of Ovarian Hyperstimulation Syndrome Reveals Distinct Biomarkers and Pathways

Ovarian hyperstimulation syndrome (OHSS) is often a complication of polycystic ovarian syndrome (PCOS), the most frequent disorder of the endocrine system, which affects women in their reproductive years. The etiology of OHSS is multifactorial, though the factors involved are not apparent. In an attempt to unveil the molecular basis of OHSS, we conducted transcriptome analysis of total RNA extracted from granulosa cells from PCOS patients with a history of OHSS (n = 6) and compared them to those with no history of OHSS (n = 18). We identified 59 significantly dysregulated genes (48 down-regulated, 11 up-regulated) in the PCOS with OHSS group compared to the PCOS without OHSS group (p-value < 0.01, fold change >1.5). Functional, pathway and network analyses revealed genes involved in cellular development, inflammatory and immune response, cellular growth and proliferation (including DCN, VIM, LIFR, GRN, IL33, INSR, KLF2, FOXO1, VEGF, RDX, PLCL1, PAPPA, and ZFP36), and significant alterations in the PPAR, IL6, IL10, JAK/STAT and NF-κB signaling pathways. Array findings were validated using quantitative RT-PCR. To the best of our knowledge, this is the largest cohort of Saudi PCOS cases (with or without OHSS) to date that was analyzed using a transcriptomic approach. Our data demonstrate alterations in various gene networks and pathways that may be involved in the pathophysiology of OHSS. Further studies are warranted to confirm the findings.

Volatilomics as an Emerging Strategy to Determine Potential Biomarkers of Female Infertility: A Pilot Study

Due to its high prevalence, infertility has become a prominent public health issue, posing a significant challenge to modern reproductive medicine. Some clinical conditions that lead to female infertility include polycystic ovary syndrome (PCOS), endometriosis, and premature ovarian failure (POF). Follicular fluid (FF) is the biological matrix that has the most contact with the oocyte and can, therefore, be used as a predictor of its quality. Volatilomics has emerged as a non-invasive, straightforward, affordable, and simple method for characterizing various diseases and determining the effectiveness of their current therapies. In order to find potential biomarkers of infertility, this study set out to determine the volatomic pattern of the follicular fluid from patients with PCOS, endometriosis, and POF. The chromatographic data integration was performed through solid-phase microextraction (SPME), followed by gas chromatography–mass spectrometry (GC-MS). The findings pointed to specific metabolite patterns as potential biomarkers for the studied diseases. These open the door for further research into the relevant metabolomic pathways to enhance infertility knowledge and diagnostic tools. An extended investigation may, however, produce a new mechanistic understanding of the pathophysiology of the diseases.