Ovarian Follicular Fluid Research Articles

Landscape transcriptomic analysis of bovine follicular cells during key phases of ovarian follicular development

BackgroundThere are many gaps in our understanding of the mechanisms involved in ovarian follicular development in cattle, particularly regarding follicular deviation, acquisition of ovulatory capacity, and preovulatory changes. Molecular evaluations of ovarian follicular cells during follicular development in cattle, especially serial transcriptomic analyses across key growth phases, have not been reported. This study aims to address this gap by analyzing gene expression using RNA-seq in granulosa and antral cells recovered from ovarian follicular fluid during critical phases of ovarian follicular development in Holstein cows.ResultsIntegrated analysis of gene ontology (GO), gene set enrichment (GSEA), protein–protein interaction (PPI), and gene topology identified that differentially expressed genes (DEGs) in the largest ovarian follicles at deviation (Dev) were primarily involved in FSH-negative feedback, steroidogenesis, cell proliferation, apoptosis, and the prevention of early follicle rupture. In contrast, DEGs in the second largest follicles (DevF2) were mainly related to loss of cell viability, apoptosis, and immune cell invasion. In the dominant (PostDev) and preovulatory (PreOv) follicles, DEGs were associated with vascular changes and inflammatory responses.ConclusionsThe transcriptome of ovarian follicular fluid cells had a predominance of granulosa cells in the dominant follicle at deviation, with upregulation of genes involved in cell viability, steroidogenesis, and apoptosis prevention, whereas in the non-selected follicle there was upregulation of cell death-related transcripts. Immune cell transcripts increased significantly after deviation, particularly in preovulatory follicles, indicating strong intrafollicular chemotactic activity. We inferred that immune cell invasion occurred despite an intact basal lamina, contributing to follicular maturation.Graphical

Seasonal influence on miRNA expression dynamics of extracellular vesicles in equine follicular fluid.

Ovarian follicular fluid (FF) is a dynamic environment that changes with the seasons, affecting follicle development, ovulation, and oocyte quality. Cells in the follicles release tiny particles called extracellular vesicles (EVs) containing vital regulatory molecules, such as microRNAs (miRNAs). These miRNAs are pivotal in facilitating communication within the follicles through diverse signaling and information transfer forms. EV-coupled miRNA signaling is implicated to be associated with ovarian function, follicle and oocyte growth and response to various environmental insults. Herein, we investigated how seasonal variations directly influence the ovulatory and anovulatory states of ovarian follicles and how are they associated with follicular fluid EV-coupled miRNA dynamics in horses. Ultrasonographic monitoring and follicular fluid aspiration of preovulatory follicles in horses during the anovulatory (spring: non-breeding) and ovulatory (spring, summer, and fall: breeding) seasons and subsequent EV isolation and miRNA profiling identified significant variation in EV-miRNA cargo content. We identified 97 miRNAs with differential expression among the groups and specific clusters of miRNAs involved in the spring transition (miR-149, -200b, -206, -221, -328, and -615) and peak breeding period (including miR-143, -192, -451, -302b, -100, and let-7c). Bioinformatic analyses showed enrichments in various biological functions, e.g., transcription factor activity, transcription and transcription regulation, nucleic acid binding, sequence-specific DNA binding, p53 signaling, and post-translational modifications. Cluster analyses revealed distinct sets of significantly up- and down-regulated miRNAs associated with spring anovulatory (Cluster 1) and summer ovulation-the peak breeding season (Clusters 4 and 6). The findings from the current study shed light on the dynamics of FF-EV-coupled miRNAs in relation to equine ovulatory and anovulatory seasons, and their roles in understanding the mechanisms involved in seasonal shifts and ovulation during the breeding season warrant further investigation.

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.

Inhibin subunit beta B (INHBB): an emerging role in tumor progression.

The gene inhibin subunit beta B (INHBB) encodes the inhibin βB subunit, which is involved in forming protein members of the transforming growth factor-β (TGF-β) superfamily. The TGF-β superfamily is extensively involved in cell proliferation, differentiation, adhesion, movement, metabolism, communication, and death. Activins and inhibins, which belong to the TGF-β superfamily, were first discovered in ovarian follicular fluid. They were initially described as regulators of pituitary follicle-stimulating hormone (FSH) secretion both in vivo and in vitro. Later studies found that INHBB is expressed not only in reproductive organs such as the ovary, uterus, and testis but also in numerous other organs, including the brain, spinal cord, liver, kidneys, and adrenal glands. This wide distribution implies its involvement in the normal physiological functions of various organs; however, the mechanisms underlying these functions have not yet been fully elucidated. Recent studies suggest that INHBB plays a significant, yet complex role in tumorigenesis. It appears to have dual effects, promoting tumor progression in some contexts while inhibiting it in others, although these roles are not yet fully understood. In this paper, we review the different expression patterns, functions, and mechanisms of INHBB in normal and tumor tissues to illustrate the research prospects of INHBB in tumor progression.

Reduced ovarian cholesterol and steroid biosynthesis along with increased inflammation are associated with high DEHP metabolite levels in human ovarian follicular fluids

The plasticizer di(2-ethylhexyl) phthalate (DEHP) is known to have endocrine-disrupting properties mediated by its many metabolites that form upon exposure in biological systems. In a previous study, we reported an inverse association between DEHP metabolites in the human ovarian follicular fluid (FF) and the responsiveness of the follicles to controlled ovarian stimulation during in vitro fertilization (IVF) treatments. Here, we explored this association further through molecular analysis of the ovarian FF samples.Ninety-six IVF patients from Swedish (N = 48) and Estonian (N = 48) infertility clinics were selected from the previous cohort (N = 333) based on the molar sum of DEHP metabolites in their FF samples to arrive at “high” (mean 7.7 ± SD 2.3 nM, N = 48) and “low” (0.8 ± 0.4 nM, N = 48) exposure groups. Extracellular miRNA levels and concentrations of 15 steroid hormones were measured across FF samples. In addition, FF somatic cells, available for the Estonian patients, were used for RNA sequencing.Differential expression (DE) and interactions between miRNA and mRNA networks revealed that the expression levels of genes in the cholesterol biosynthesis and steroidogenesis pathways were significantly decreased in the high compared to the low DEHP group. In addition, the DE miRNAs were predicted to target key enzymes within these pathways (FDR < 0.05). A decreased 17-OH-progesterone to progesterone ratio was observed in the FF of the high DEHP group (p < 0.05). Additionally, the expression levels of genes associated with inflammatory processes were elevated in the FF somatic cells, and a computational cell-type deconvolution analysis suggested an increased immune cell infiltration into the high DEHP follicles (p < 0.05).In conclusion, elevated DEHP levels in FF were associated with a significantly altered follicular milieu within human ovaries, involving a pro-inflammatory environment and reduced cholesterol metabolism, including steroid synthesis. These results contribute to our understanding of the molecular mechanisms of female reprotoxic effects of DEHP.

O-005 The in vitro maturation rate of human oocytes is enhanced following uptake of extracellular vesicles derived from mature follicles

Abstract Study question Could follicular fluid derived extracellular vesicles (ffEVs) impact human oocyte in vitro maturation (IVM)? Summary answer Supplementation of IVM culture with ffEVs isolated from mature follicles enhanced oocyte maturation rates by &amp;gt; 20%, inducing changes in oocyte protein profile and organelle distribution. What is known already IVM involves the culture of immature germinal vesicle (GV) oocytes under set laboratory conditions to allow for their transition to mature metaphase II (MII) stage, which is confirmed by the extrusion of the first polar body. Efficient IVM could circumvent aggressive controlled ovarian stimulation (COS), reduce the cost and broaden the repertoire of infertility treatments. Animal studies suggest that extracellular vesicles (EVs), membranous nanosized vesicles containing different molecular content (e.g. nucleic acids, proteins) and present in the ovarian follicular fluid could facilitate oocyte maturation. The uptake of ffEVs by bovine, equine and feline oocytes, but not human, has been demonstrated. Study design, size, duration Women undergoing transvaginal oocyte retrieval after COS (n = 83) at University Hospital Zurich donated follicular fluid (n = 54 single follicles) and/or immature GV oocytes (n = 95). We aimed to: a) define differences in the protein cargo of ffEVs derived from follicles containing mature oocytes (MII-ffEVs, n = 10) versus (vs.) immature oocytes (GV-ffEVS, n = 5; metaphase I MI-ffEVs, n = 5), b) demonstrate the capacity of GV oocytes to uptake mature MII-ffEVs and c) determine the effect of MII-ffEVs supplementation on oocyte maturation. Participants/materials, setting, methods ffEVs were isolated by ultracentrifugation. The protein content of ffEVs was analysed by mass spectrometry. The uptake of fluorescently-labelled MII-ffEVs by GV oocytes (n = 15) was assessed by confocal microscopy. GVs were cultured for rescue-IVM in a timelapse incubator with MII-ffEVs (n = 45 GVs) or without (n = 40 GVs) and extrusion of polar body denoted maturation. The impact of MII-ffEVs supplementation on IVM-matured oocytes was assessed through single-cell proteomics and intracellular organelles appearance with transmission electron microscopy (TEM). Main results and the role of chance Successful isolation of ffEVs was confirmed by TEM and Western blotting analysis for characteristic protein markers of EVs (TSG101 and CD63). Mass spectrometry identified a total of 1340 proteins across ffEVs samples. Statistical analysis revealed differentially abundant proteins (DAPs) in ffEVs: 61 DAPs in the comparison MII-ffEVs vs. GV-ffEVs, 15 DAPs in MII-ffEVs vs. MI-ffEVs and 14 DAPs in MI-ffEVs vs GV-ffEVs (FDR&amp;lt;0.2). Among the 61 DAPs, 7 proteins in higher abundance in MII-ffEVs (&amp;gt;log2 fold change) were related to oocyte maturation, lipid accumulation, calcium binding and the coagulation cascade (e.g. FABP5, S100A9, F12, SERPINA10). Confocal microscopy confirmed the uptake of MII-ffEVs by GV oocytes after 24 hours of co-incubation. Supplementation of IVM culture with MII-ffEVs for 48 hours significantly increased the oocyte maturation rate compared to control by 22.8±9.4% (77.8% vs 55% mature oocytes respectively; P-value=0.0372). Single oocyte proteomics of IVM-matured oocytes revealed 59 DAPs (FDR 0.1) between ffEVs-supplemented and control groups. Among them, 37 DAPs were in higher abundance in ffEVs-supplemented mature oocytes (&amp;gt;log2 FC) including Hyaluronan Synthase 1 (HAS1) that is associated with oocyte maturation (6.55 fold increase). TEM revealed differences in oocyte organelle distribution and appearance, particularly of endoplasmic reticulum (RE) and RE-mitochondria complexes. Limitations, reasons for caution This study utilised immature oocytes from stimulated cycles, therefore these results should be interpreted within the context of rescue-IVM potential. Wider implications of the findings Our findings pave the way for further mechanistic studies on the role of ffEVs in supporting oocyte maturation and inspire the development of clinical IVM supplements as well as novel complementary regimes for COS based on ffEVs or their associated specific cargo. Trial registration number N/A

Is it safe to use ovarian follicular fluid from cows seropositive for brucellosis in the production of invitro embryos?

Animal reproduction biotechniques are important tools for the technological advancement of livestock, as they allow the selection of the reproductive potential of superior quality females and males; however, infectious diseases that have a predilection for the reproductive system can be a hindrance for the use of these technologies. Therefore, the present study aimed to detect Brucella spp. in the ovarian follicular fluid of brucellosis-positive bovine cows. A total of 47 bovine ovarian follicular fluid aspirates from cows, positive in tests for brucellosis and from Brucella-positive herd, were submitted to PCR. The primers used in the PCR were specific to the genus Brucella (bcsp31 gene). All 47 bovine aspirates were negative for Brucella spp. 0.00% (95% CI: 0.00-4.00%). Our results demonstrated that Brucella spp. was absent in the ovarian follicular fluid from seropositive cows, which indicates that Brucella spp.-infected cows could be used for reproductive biotechnologies carried out with follicular aspirates. Future studies are needed to more precisely evaluate the feasibility and safety of using these oocytes from brucellosis-seropositive cows to transfer embryos to heifers/cows not infected by Brucella, aiming to produce calves free of the infection.

Levothyroxine may not adequately prepare hypothyroid women for controlled ovarian hyperstimulation

BackgroundThyroid axis dysregulation during controlled ovarian hyperstimulation (COH) is more pronounced in hypothyroid‐treated women. Whether or not this leads to compromised thyroid hormone levels within the ovarian follicular fluid is not known.AimsTo determine whether ovarian follicular thyroid hormone levels are compromised in adequately replaced hypothyroid women undergoing controlled ovarian hyperstimulation (COH), and/or influence cycle/pregnancy outcomes.Materials and MethodsProspective cohort study involving 46 euthyroid (anti‐thyroid peroxidase antibody negative) and 16 levothyroxine‐replaced women with baseline thyroid‐stimulating hormone (TSH) &lt;2.5 mIU/L attending their first COH cycle. Follicular fluid TSH, free triiodothyronine (T3) and free thyroxine (T4) were recorded at oocyte pick‐up. Serum levels were measured at: (i) baseline; (ii) human chorionic gonadotropin trigger day; and (iii) cycle conclusion. The number of mature oocytes retrieved, fertilisation, early pregnancy loss and live birth rates were compared.ResultsMedian serum TSH levels were similar at baseline (1.76 vs 1.24 mIU/L, P = 0.053), but free T3 levels were lower (4.5 vs 4.8 pmol/L, P = 0.029) in levothyroxine‐replaced compared to euthyroid women, with serum TSH levels increasing across ovarian stimulation (P = 0.006) into pregnancy testing (P = 0.030). Follicular fluid free T3 levels were lower in levothyroxine‐replaced women (median 4.3 vs 4.6 pmol/L, P = 0.032). Fertilisation rates were lower (52% vs 71%, P = 0.043) in women requiring levothyroxine replacement, but numbers of mature oocytes retrieved, early pregnancy loss and live births did not differ.ConclusionAdequately replaced hypothyroid women achieve lower ovarian follicular fluid free T3 levels and poorer fertilisation rates compared to euthyroid women undergoing COH. Optimising T3 levels may be pivotal in improving COH outcomes in hypothyroid women.

The Presence of TGFβ3 in Human Ovarian Intrafollicular Fluid and Its Involvement in Thromboxane Generation in Follicular Granulosa Cells through a Canonical TGFβRI, Smad2/3 Signaling Pathway and COX-2 Induction.

Ovarian follicular fluid (FF) has a direct impact on oocyte quality, playing key roles in fertilization, implantation, and early embryo development. In our recent study, we found FF thromboxane (TX) to be a novel factor inversely correlated with oocyte maturation and identified thrombin, transforming growth factor β (TGFβ), TNF-α, and follicular granulosa cells (GCs) as possible contributors to FF TX production. Therefore, this study sought to investigate the role of TGFβ3 in regulating TX generation in human ovarian follicular GCs. TGFβ3 was differentially and significantly present in the FF of large and small follicles obtained from IVF patients with average concentrations of 68.58 ± 12.38 and 112.55 ± 14.82 pg/mL, respectively, and its levels were correlated with oocyte maturity. In an in vitro study, TGFβ3 induced TX generation/secretion and the converting enzyme-COX-2 protein/mRNA expression both in human HO23 and primary cultured ovarian follicular GCs. While TGFβRI and Smad2/3 signaling was mainly required for COX-2 induction, ERK1/2 appeared to regulate TX secretion. The participation of Smad2/3 and COX-2 in TGFβ3-induced TX generation/secretion could be further supported by the observations that Smad2/3 phosphorylation and nuclear translocation and siRNA knockdown of COX-2 expression compromised TX secretion in GCs challenged with TGFβ3. Taken together, the results presented here first demonstrated that FF TGFβ3 levels differ significantly in IVF patients' large preovulatory and small mid-antral follicles and are positively associated with oocyte maturation. TGFβ3 can provoke TX generation by induction of COX-2 mRNA/protein via a TGFβR-related canonical Smad2/3 signaling pathway, and TX secretion possibly by ERK1/2. These imply that TGFβ3 is one of the inducers for yielding FF TX in vivo, which may play a role in folliculogenesis and oocyte maturation.

The Potential Impacts of Selecting Viable Oocytes on Further Embryonic Development in Mammals: A Review

Selecting viable fully grown germinal and matured oocytes were positively effect on further embryonic development and live birth. The use of feed and hormonal supplementation and biotechnologies to enhance oocyte competence was evaluated. In addition, the oocytes were selected based on ovarian follicular stage, follicles and oocytes morphology, follicular fluid characters and gene expression. Changes were obtained in oocyte maturation, fertilization and further embryo cleavage and development over selecting viable oocytes. The larger follicle diameter, the translucent follicle and the higher blood supply the higher developmental competence of resulting oocytes. The higher surrounding cumulus cells and homogeneity of cytoplasm the higher developmental competence of oocytes. In addition, oocytes obtained during luteal stage compared to those obtained during follicular phase were highly or comparably developed to embryos. Furthermore, follicular fluid characters and gene expression might predict the embryonic developmental competence of oocytes in addition to their viable staining with brilliant cresyl blue. In conclusion, the characters of ovarian follicles, oocytes, follicular fluid and gene expression have significant implications on further oocyte developmental competence in different mammalian species.

Morphological Characteristics of Ovarian Tissues and Follicular Fluid Metabolites of Female Lambs and Ewes in Subtropics

Background: Oocyte and follicular fluid recovery and evaluation are a crucial step in assisted reproductive technologies. The aims of the current study were to evaluate the ovarian tissues and their resulting oocytes and follicular fluid of Awassi female lambs and ewes in subtropics of Saudi Arabia. Methods: Thirty reproductive systems of female lambs in addition to forty reproductive systems of ewes of follicular and luteal phases were collected. The ovarian tissues were evaluated through ovarian follicle numbers, oocytes recovery in addition to determination of follicular fluid (FF) metabolites. The ovarian follicles were categorized into small ( less than 3 mm), medium (3-5 mm) and large follicles ( greater than 5 mm). The medium and large ovarian follicles were aspirated for FF collection and oocytes recovery. The FF concentrations of total protein (g/dl), urea (mg/dl), glucose (mg/dl), total cholesterol (mg/dl) and triglycerides (mg/dl) were determined. Result: The weight of reproductive system and ovary were increased of ewes compared to female lambs. The number of small follicles was not differed among groups whereas the numbers of medium and large follicles increase in ewes groups. The highest number of medium follicles was found in ewes of follicular phase compared to other groups. Although the percentage of oocyte recovery increased in ewes compared to lambs, the oocytes quality was not differed among groups. The total protein values were high (P less than 0.05) in FF of ewes compared to that of female lambs. On the other, the values of urea and triglycerides were low (P less than 0.05) in FF of ewes compared to FF of female lambs. Moreover, the values of total protein, urea and triglycerides were comparable in FF of ewes during follicular or luteal phase. Additionally, there is slight increase of glucose and slight decrease of total cholesterol values in FF of ewes compared to FF of female lambs. In conclusion, follicles of ovarian tissues, oocyte recovery and quality and follicular fluid biochemistry of female lambs and ewes showed differences. The recovered oocytes and FF are available for assisted reproductive techniques.

Correlation of Metabolic and Ionic Components of Follicular Fluid with Estrogen Concentration

This study was aimed to assess the correlation between the metabolic and ionic composition of ovarian follicular fluid and its relationship to the concentration of estrogen and prolactin hormones as the follicle size changes in the local female cows. Ovaries were collected (80 ovaries) from non- pregnant 40 adult females cow at Hilla slaughterhouse at Babil province. The gathered ovaries were transported to the laboratory within two hours. Follicular fluid was pulled from small (2-5 mm) follicles, medium (6-10 mm), and large (11-20 mm) follicles, then it stored at 5 ° C until assayed. Follicular fluid samples were analyzed for metabolites composition of (cholesterol, total protein, and glucose), and ionic composition (calcium, phosphorus, copper, magnesium, zinc) ,and hormone concentration ( estrogen and prolactin). The results of the study showed that the total protein and glucose concentrations were increased significantly(p&gt; 05.0) with increased of follicle size. The study also showed the calcium, copper, and phosphorus concentration were increased significantly(p&gt; 05.0) with changes of follicular size, as well as the estrogen concentration was significantly increased (p &gt; 05.0) With increased follicular size. A significantly (p&gt; 05.0) correlation was found between both magnesium, zinc ions, and estrogen hormone.

Transcriptomics and metabolomics of blood, urine and ovarian follicular fluid of yak at induced estrus stage

To gain a deeper understanding of the metabolic differences within and outside the body, as well as changes in transcription levels following estrus in yaks, we conducted transcriptome and metabolome analyses on female yaks in both estrus and non-estrus states. The metabolome analysis identified 114, 13, and 91 distinct metabolites in urine, blood, and follicular fluid, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis highlighted an enrichment of pathways related to amino acid and lipid metabolism across all three body fluids. Our transcriptome analysis revealed 122 differentially expressed genes within microRNA (miRNA) and 640 within long non-coding RNA (lncRNA). Functional enrichment analysis of lncRNA and miRNA indicated their involvement in cell signaling, disease resistance, and immunity pathways. We constructed a regulatory network composed of 10 lncRNAs, 4 miRNAs, and 30 mRNAs, based on the targeted regulation relationships of the differentially expressed genes. In conclusion, the accumulation of metabolites such as amino acids, steroids, and organic acids, along with the expression changes of key genes like miR-129 during yak estrus, provide initial insights into the estrus mechanism in yaks.

Follicular fluid-derived exosomes rejuvenate ovarian aging through miR-320a-3p-mediated FOXQ1 inhibition

Abstract Ovarian aging is mainly characterized by a progressive decline in oocyte quantity and quality, which ultimately leads to female infertility. Various therapies have been established to cope with ovarian aging, among which exosome-based therapy is considered a promising strategy that can benefit ovarian functions via multiple pathways. Here, we isolated and characterized exosomes derived from ovarian follicular fluid and profiled the differential expression patterns of noncoding exosomal RNAs in young and aged women. Treatment with young mouse-derived exosomes efficiently rescued ovarian function in aged mice. The follicular fluid exosomes from young mice and miR-320-3p can also promote the proliferation of ovarian granulosa cells and improve mitochondrial function from old mice in vitro. The mechanism may be involve that exosomes transfer miR-320-3p to granulosa cells, and inhibit the expression of FOXQ1. Exosomes also can increase the number of primordial and growing follicles, and improve the developmental ability of oocytes in the old mice in vivo. And hnRNPA2B1 controls miR-320-3p entry into exosomes. This work provides insights into the antiaging potential of follicular fluid-derived exosomes and the underlying molecular mechanisms, which may facilitate prevention of ovarian aging and an improvement in female fertility.

Development and evaluation of a comprehensive workflow for suspect screening of exposome-related xenobiotics and phase II metabolites in diverse human biofluids

Suspect and non-target screening (SNTS) methods are being promoted in order to decode the human exposome since a wide chemical space can be analysed in a diversity of human biofluids. However, SNTS approaches in the exposomics field are infra-studied in comparison to environmental or food monitoring studies. In this work, a comprehensive suspect screening workflow was developed to annotate exposome-related xenobiotics and phase II metabolites in diverse human biofluids. Precisely, human urine, breast milk, saliva and ovarian follicular fluid were employed as samples and analysed by means of ultra-high performance liquid chromatography coupled with high resolution tandem mass spectrometry (UHPLC-HRMS/MS). To automate the workflow, the “peak rating” parameter implemented in Compound Discoverer 3.3.2 was optimized to avoid time-consuming manual revision of chromatographic peaks. In addition, the presence of endogenous molecules that might interfere with the annotation of xenobiotics was carefully studied as the employment of inclusion and exclusion suspect lists. To evaluate the workflow, limits of identification (LOIs) and type I and II errors (i.e., false positives and negatives, respectively) were calculated in both standard solutions and spiked biofluids using 161 xenobiotics and 22 metabolites. For 80.3 % of the suspects, LOIs below 15 ng/mL were achieved. In terms of type I errors, only two cases were identified in standards and spiked samples. Regarding type II errors, the 7.7 % errors accounted in standards increased to 17.4 % in real samples. Lastly, the use of an inclusion list for endogens was favoured since it avoided 18.7 % of potential type I errors, while the exclusion list caused 7.2 % of type II errors despite making the annotation workflow less time-consuming.

Bisphenol a downregulates GLUT4 expression by activating aryl hydrocarbon receptor to exacerbate polycystic ovary syndrome

BackgroundBisphenol A (BPA) levels are high in women with polycystic ovary syndrome (PCOS). The mechanism by which BPA induces abnormal glucose metabolism in PCOS patients is largely unknown.MethodsSerum and urine samples were collected from women with and without PCOS (control) at the reproductive medicine center with informed consent. Non-PCOS patients who received in vitro fertilization were recruited for collection of ovarian follicular fluid and granular cells. Wild-type C57BL/6 and AhR−/− mice were used to verify the effects of BPA on PCOS. Real-time PCR, western blotting, and ELISA were conducted to analyze the function of BPA. Chip-qPCR verified the role of AhR in GLUT4 transcription. Flow cytometry was performed to determine glucose uptake.ResultsA positive correlation was observed between BPA concentration and serum BPA levels in PCOS patients. BPA aggravated the changes in PCOS with abnormal glucose metabolism, impaired fertility, and increased body fat. Mechanistically, we showed that BPA activated AhR and led to decreased glucose transport via GLUT4 downregulation in ovarian granular cells. Therefore, the use of inhibitors or knockout of AhR could effectively rescue BPA-induced metabolic disorders in PCOS mice.ConclusionsOur results revealed that BPA suppressed GLUT4 expression and induced abnormal glucose metabolism by activating AhR, causing insulin resistance, and is thus a potential contributor to the development of PCOS. Therefore, AhR could be a potential new therapeutic target for PCOS.Dp7QWqxpppdxU99YCnw6gzVideo

Metabolomic profiling of exosomes reveals age-related changes in ovarian follicular fluid

BackgroundFemale fertility declines with increased maternal age, and this decline is even more rapid after the age of 35 years. Follicular fluid (FF) is a crucial microenvironment that plays a significant role in the development of oocytes, permits intercellular communication, and provides the oocytes with nutrition. Exosomes have emerged as being important cell communication mediators that are linked to age-related physiological and pathological conditions. However, the metabolomic profiling of FF derived exosomes from advanced age females are still lacking.MethodsThe individuals who were involved in this study were separated into two different groups: young age with a normal ovarian reserve and advanced age. The samples were analysed by using gas chromatography–time of flight mass spectrometry (GC–TOFMS) analysis. The altered metabolites were analysed by using Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis to identify the functions and pathways that were involved.ResultsOur data showed that metabolites in exosomes from FF were different between women of young age and women of advanced age. The set of 17 FF exosomal metabolites (P ≤ 0.05) may be biomarkers to differentiate between the two groups. Most of these differentially expressed metabolites in FF were closely involved in the regulation of oocyte number and hormone levels.ConclusionsIn this study, we identified differences in the metabolites of exosomes from FF between women of young age and women of advanced age. These different metabolites were tightly related to oocyte count and hormone levels. Importantly, these findings elucidate the metabolites of the FF exosomes and provide a better understanding of the nutritional profiles of the follicles with age.

Progesterone and 17-hydroxy-progesterone concentrations in follicular fluid and serum reflect their production in granulosa and theca cells

Research QuestionHow is the production of progesterone (P4) and 17-hydroxy-P4 (17-OH-P4) regulated between theca (TCs) and granulosa cells (GCs) during the follicular phase, during ovulation and after transformation into a corpus luteum? DesignThree cohorts were examined: 1) 31 women undergoing natural and stimulated cycles, with serum hormone measurements taken every 3 days; 2) 50 women undergoing ovarian stimulation, with serum and follicular fluid (FF) hormones assessed at five-time points during final follicle maturation; 3) 12 women undergoing fertility preservation, with hormone concentrations evaluated via small antral follicle FF. ResultsIn the early follicular phase, TCs primarily synthesise 17-OH-P4 while GCs produce limited P4, maintaining the P4 /17-OH-P4 ratio below one. As follicles reached follicle selection around 10 mm in diameter, P4 synthesis in GCs became upregulated but was mainly accumulated in FF. During final maturation, the enhanced activity of the enzyme HSD3B2 in GCs boosted P4 production with the P4 /17-OH-P4 ratio increasing to more than one. The luteal phase showed similar 17-OH-P4 levels to that of the follicular phase, but P4 production increased yielding a P4/17-OH-P4 ratio significantly above one. ConclusionsThe P4 /17-OH-P4 ratio reflects GC-TC activity during the follicular phase and following luteinisation in the corpus luteum. Managing GC function is key for reducing P4 during ovarian stimulation, but the concerted action of FSH and LH on GCs during the second half of the follicular phase makes this complex.

Assessment of heavy metal and radioactive element levels in the ovarian follicular fluid of pregnant and non-pregnant Kyrgyz breed mares

Objective: In the current study, we aimed to ascertain the levels of heavy metals and radioactive elements in the ovarian follicular fluids of pregnant and non-pregnant Kyrgyz mares. Materials and Methods: To this end, follicular fluids were obtained from 49 Kyrgyz mares aged 3–5 years. The mares were in various stages of pregnancy (Group 1, n = 27) or were non-pregnant (Group 2, n = 22). We measured the levels of cadmium (Cd), lead (Pb), mercury (Hg), antimony (Sb), cobalt (Co), potassium (K), uranium (U), nickel (Ni), and thorium (Th) in follicular fluids using atomic emission mass spectrometry. Subsequently, the data were statistically analyzed according to whether the mare was pregnant or not, the pregnancy stage, the presence or absence of the corpus luteum in the ovaries, the corpus luteum’s diameter if present, and the presence or absence and diameter of follicles. Results: We found that K levels were higher in non-pregnant mares (0.00564 ± 0.000590 ppm, p = 0.009). Furthermore, Ni (0.01033 ± 0.001880 ppm, p = 0.07) and K (0.00563 ± 0.000498 ppm, p = 0.026) levels were higher in mares with a follicle diameter of 1–3 cm. However, these results did not change according to the month of pregnancy, number of follicles, presence or absence of the corpus luteum in the ovaries, number of corpora lutea, and their diameters. Conclusion: Thus, we concluded that heavy metal and radioactive element levels in the ovarian follicular fluids of Kyrgyz mares do not significantly change with pregnancy status, and there are limited detrimental effects of pollution on the follicular fluids.

The effectiveness of assisted reproductive technologies immunological prediction

The high frequency of infertility is a significant medical and social problem in many countries of the world; assisted reproductive technologies (ART) are actively used to solve it. Given that immune responses play an important role in the development and maintenance of pregnancy, the study of changes in immune parameters is relevant in different trimesters of pregnancy, as well as at the stage of preconception preparation. It is believed that the maternal-fetal relationship is not limited to the development of maternal tolerance to fetal antigens, but is complemented by complex cytokine interactions that control selective immune regulation, control of adhesion and vascularization processes during embryo implantation and pregnancy. The purpose of the review was to analyze the available scientific data on the use of immune parameters to predict the effectiveness of ART. A review of Russian and foreign scientific papers on prevalence, immunopathogenetic mechanisms, and infertility diagnostics was carried out. A multi-criteria search was carried out for inventions, abstracts of patent documents on immunological prediction of the effectiveness of ART. As predictors, immunocompetent cells (CD3+-, CD4+-, CD3-CD16+56+-venous blood lymphocytes, CD95+ macrophages of endometrial biopsy), cytokines, pregnancy glycoproteins, autoantibodies, immunogenetic markers are presented. The study of the quantitative level of cytokines in blood serum, ovarian follicular fluid and endometrium as mediators of intercellular and intertissue interactions is of undoubted scientific and practical interest in terms of establishing their discriminatory levels specific to different trimesters of a normal pregnancy, the threat of miscarriage, and infertility. There was an association with non-occurrence of pregnancy due to in vitro fertilization of an increased content of interleukin (IL)-2 and interferon (IFN)-γ in the follicular fluid, and a soluble receptor IL-2-α, IL-8 and lactoferrin in the blood serum. The immunosuppressive effects of pregnancy-associated α2-glycoprotein, trophoblastic β1-glycoprotein, α-fetoprotein, α2-macroglobulin contribute to the development and maintenance of pregnancy, but their prognostic value is not unambiguous. The study of the content of immunoglobulins G to α2-macroglobulin, lactoferrin, progesterone, estradiol, cardiolipin in the follicular fluid and blood serum makes it possible to predict the result of ART. Conclusion. The study of immune parameters, especially in combination with sex hormones and characteristics of the state of the embryo, in infertile women has diagnostic value and prognostic significance, and can contribute to the timely correction of therapy and the ART program.