Search Results (389)

Ovarian tissue cryopreservation is the primary fertility preservation strategy for prepubertal girls and patients requiring urgent gonadotoxic therapy. However, the risk of reintroducing malignant cells has prompted the development of safer alternatives, including follicle isolation followed by three-dimensional scaffold encapsulation for transplantation. Fibrin is a promising biomaterial for bioengineered ovary construction, although its ability to support early human follicle maintenance remains unclear. Follicles isolated from cryopreserved ovarian tissues of six patients were encapsulated within fibrin scaffolds of graded concentrations (high, medium, low). After 7 days of in vitro culture, follicle survival and diameter change were quantified. A total of 282 follicles (45.4 ± 10.1 µm) were embedded into fibrin scaffolds. After culture, 237 viable follicles were detected, yielding an overall survival of 84%. Follicle diameter increased to 58.8 ± 12.0 µm. Follicle survival rates were comparable across groups, while mean follicle diameter was 56.3 ± 12.5 µm (high), 61.9 ± 13.4 µm (medium), and 57.4 ± 9.3 µm (low). Follicles cultured in medium-concentration fibrin demonstrated significantly larger diameters compared with both high and low groups (p < 0.05), with no difference between high and low groups. Fibrin-based bioprosthetic ovary scaffolds support short-term in vitro maintenance of isolated human follicles, preserving spherical morphology and granulosa cell layer integrity. Medium-concentration fibrin was associated with greater follicle diameter expansion compared with higher and lower concentrations, indicating that scaffold composition influences early morphometric changes during in vitro follicle culture. Full article

Ovarian function relies on a network of well-coordinated molecular mechanisms that regulate follicular development, oocyte maturation, ovulation, and corpus luteum function. When these processes are disrupted, infertility can result. Extracellular matrix (ECM) remodeling represents a central regulatory component in these processes and is essential for follicle rupture and oocyte release. This mechanism involves metalloproteinases (MMPs), mainly MMP-2 and MMP-9, which degrade the ECM and allow the necessary structural changes. Other ECM-modulating proteases, such as ADAM and ADAMTS families, also contribute to this process. Their activity is tightly regulated by tissue inhibitors of metalloproteinases (TIMPs), ensuring that tissue remodeling occurs in a controlled manner. Disruption of the balance between MMPs and TIMPs increases the risk of infertility-related conditions such as polycystic ovary syndrome (PCOS), endometriosis, luteinizing hormone (LH) deficiency syndrome, and ovarian aging. In addition to the ECM, other factors, including intracellular signaling pathways, oxidative stress (OS), and mitochondrial function, contribute to ovarian physiology and directly affect oocyte quality and viability. This narrative review focuses on the molecular mechanisms governing ovarian function, with particular emphasis on the remodeling of the ECM by MMPs during ovulation, and examines how their disorders contribute to infertility. A deeper understanding of these mechanisms may lead to the identification of new therapeutic targets and the improvement of assisted reproduction outcomes. Full article

Proper steroid hormone synthesis is essential for maintaining fertility in female animals. Tribbles pseudokinase 1 (Trib1), a member of the Tribbles pseudokinase family, exerts its functions mainly through interacting with other molecules. Numerous studies have shown that Trib1 plays a central role in regulating cell proliferation. In mammals, the proliferation of granulosa cells (GCs) is a hallmark event in follicular development, which is essential for follicular maturation and successful ovulation. However, whether Trib1 regulates ovarian steroid hormone synthesis remains largely unexplored. In this study, we found that Trib1 is predominantly expressed in ovarian GCs. Knockdown of Trib1 in GCs significantly reduced their capacity for steroid hormone synthesis. Furthermore, Trib1 KO female mice were completely infertile, exhibiting impaired transition from primary to antral follicles, increased follicle atresia, and defective steroid hormone secretion. Ovarian RNA-Seq analysis revealed that differential expressed genes (DEGs) were significantly enriched in cholesterol metabolism and steroid biosynthesis pathways following Trib1 deletion. Notably, FOSL2, a transcription factor that potentially bound to the promoters of the pivotal steroidogenic genes Star and Cyp11a1, was significantly down-regulated in Trib1 KO mice. Crucially, overexpression of FOSL2 in Trib1-deficient GCs restored Star and Cyp11a1 expression and significantly rescued the ability of steroid hormone synthesis in GCs. Our findings unveil a novel Trib1 gene governing steroidogenesis in GCs and is essential for fertility in female mice, providing profound insights into the female reproductive endocrinology and potential therapeutic targets. Full article

Background/Objectives: Osteoarthritis has been increasingly described as associated with systemic inflammation, raising the question of how it would affect fertility in young women with or without reproductive hormone administration. We studied oogenesis in mice with collagenase-induced osteoarthritis (CIOA) as a model system with fewer ethical limitations after estradiol (E2) or follicle-stimulating hormone (FSH) treatment. Methods: Oocytes have been isolated from mice subjected to various treatment regimens. The meiotic spindle, the chromatin, and the actin cap were fluorescently labeled and analyzed. Results: In addition to reduced maturation rates, specific oocyte abnormalities were registered when CIOA, FSH, or E2 were applied in isolation. Combined treatments showed that the spindle, chromatin, and actin cytoskeleton parameters were differently affected in oocytes from groups with CIOA treated by estradiol and those treated with FSH. Enlarged spindles, ooplasmic tubulin asters, aligned metaphases, and predominantly normal actin caps, often with an actin halo, were typical for groups with CIOA combined with estradiol. The groups with CIOA and FSH had slightly enlarged spindles, unaligned metaphases with degenerated chromatin surrounded by a cloud of depolymerized tubulin, and small actin caps. Conclusions: Our results show that experimental osteoarthritis with or without exogenous reproductive hormones negatively affects oogenesis, presumably due to systemic inflammatory factors making the ovarian microenvironment less capable of supporting oocyte maturation. Estradiol supplementation does not benefit oogenesis. FSH treatment induced cytoskeletal and chromatin abnormalities that presumably disturb the fertilization and development potential of affected oocytes. These data can have implications for assisted reproduction in cases of patients with osteoarthritis. Full article

Oocyte competency is a crucial determinant of fertilisation success and the initial development of embryos in assisted reproductive technologies. The metabolic and biochemical environment of the ovarian follicle is crucial for determining oocyte developmental potential, alongside genetic integrity. The follicular microenvironment includes a complex network of signalling chemicals that regulate mitochondrial activity, steroidogenesis, oxidative balance, and cellular energy metabolism. Recently, metabolic hormones originating from adipose tissue and skeletal muscle, namely, adipokines and myokines, have received considerable focus as crucial regulators of ovarian physiology. Adiponectin, irisin, and the recently identified hormone asprosin have emerged as crucial metabolic regulators influencing granulosa cell activity, mitochondrial bioenergetics, insulin signalling pathways, and redox homeostasis inside the follicular niche. Adiponectin mostly provides metabolic protection by activating AMP-activated protein kinase (AMPK) and improving insulin sensitivity, which in turn enhances mitochondrial efficiency and steroidogenic function in granulosa cells. Irisin, derived from the breakdown of fibronectin type III domain-containing protein 5 (FNDC5), aids the developing oocyte by facilitating mitochondrial biogenesis, augmenting oxidative phosphorylation, and altering cellular defence mechanisms against oxidative stress. Conversely, asprosin has been associated with glucogenic signalling, metabolic stress, and probable mitochondrial malfunction, suggesting a possible relationship between systemic metabolic problems and negative reproductive consequences. Clinical and experimental research indicate that the levels of these metabolic regulators in follicular fluid may correlate with ovarian response, oocyte quality, fertilisation rates, and embryo development during in vitro fertilisation cycles. This review consolidates current molecular, cellular, and clinical information, clarifying the pathways by which adipokines and myokines influence follicular metabolism and impact oocyte competency. Understanding the metabolic connections between systemic endocrine signals and the follicular milieu may provide novel indicators for reproductive prognosis and provide new treatment targets to improve assisted reproduction outcomes. Full article

Halogenated derivatives of polycyclic aromatic hydrocarbons (PAHs), such as chlorinated PAHs (ClPAHs), are an emerging class of contaminants that are being detected in the environment as well as in wildlife and human populations. Previous studies have shown that chemical substitution of PAHs, including chlorination, may alter the toxicity of parent PAHs; however, whether chlorination affects their endocrine-disrupting potential remains unexplored. In this study, we examined the effects of phenanthrene (Phe), one of the most prevalent PAHs, and its chlorinated congeners, 9-chlorophenanthrene (9ClPhe) and 9,10-dichlorophenanthrene (9,10Cl₂Phe), on hormone production in granulosa cells, key hormone-secreting cells of the ovary. We observed that Phe and its chlorinated congeners differentially altered anti-Müllerian hormone (AMH), estradiol (E2), and progesterone (P4) secretion. Since mitochondria are central to steroidogenesis, we further evaluated mitochondrial function. While Phe increased ATP production, both 9ClPhe and 9,10Cl₂Phe increased ROS, decreased mitochondrial membrane potential, and reduced the expression of markers for mitochondrial dynamics and mitophagy without altering ATP levels. We further tested impacts on cell fate and found that neither Phe nor its chlorinated congeners altered granulosa cell apoptosis. Together, these results suggest that chlorination of Phe leads to dose-dependent, differential effects on hormone production and mitochondrial pathways without inducing cell death in granulosa cells. This study highlights the potential adverse impacts of ClPAH exposure on ovarian follicle development and female fertility by disrupting steroidogenesis and mitochondrial quality control. Full article

Ovarian reserve and reproductive life are closely linked concepts in female reproductive biology. The ovarian reserve consists of primordial follicles and refers to the number and quality of oocytes (eggs) remaining in the ovaries at any given time. Follicular dynamics shape a woman’s reproductive lifespan, ultimately leading to menopause. Elucidating the underlying genetic and molecular pathways of follicle maturation and depletion is thus crucial for understanding menopausal onset and progression, both in normal and pathophysiological contexts, such as primary ovarian insufficiency, defined as menopause before the age of 40. A key factor in ovarian differentiation and fertility maintenance is FOXL2, a forkhead family transcription factor that plays a crucial role in follicle formation and development, ovarian maintenance, and sex determination. By employing a ChIP-Seq approach in mice, we identified a previously unreported binding of FOXL2 to a Tsc1 regulatory region. Our data, along with a thorough literature review, support the hypothesis that FOXL2-mediated activation of Tsc1 in granulosa cells can help maintain primordial follicles in a dormant state by suppressing mTORC1 signalling. Understanding the mechanisms behind ovarian reserve may lay the foundation for developing novel fertility preservation strategies, improving fertility treatment protocols and promoting in vitro activation of cryopreserved ovarian tissue to support folliculogenesis. Full article

Background: Polycystic ovary syndrome (PCOS) is characterized by substantial inter-individual variability in ovarian sensitivity to recombinant follicle-stimulating hormone (rFSH) during controlled ovarian stimulation (COS). Clinically applicable tools for personalized dosing in this population remain limited. Methods: This retrospective single-center study (2013–2024) analyzed 369 PCOS patients undergoing GnRH antagonist protocols who achieved optimal ovarian responses (10–20 oocytes with at least 40% of follicles ≥ 16 mm in diameter on trigger day). The final retrospective dataset was randomly split into modeling (n = 258) and validation (n = 111) groups. A multivariate linear regression model incorporating age, BMI, basal FSH, basal LH, AMH, and AFC was developed to estimate the average daily rFSH dose. Model performance was evaluated using correlation analysis, prediction error metrics, and calibration assessment. Results: Age, BMI, and basal FSH were positively associated with average daily rFSH dose, whereas basal LH, AMH, and AFC were negatively associated. The model explained 40.4% of the variability in average daily rFSH dose. In the modeling cohort, 77.9% of estimated doses fell within ±20% of the observed values, with a moderate correlation between predicted and observed doses (ρ = 0.646). In the validation cohort, 67.6% of estimates met the predefined accuracy threshold (ρ = 0.676). Calibration analyses demonstrated robust agreement between predicted and observed doses. Conclusions: By integrating endocrine markers, ovarian reserve indicators, and clinical characteristics, this study provides a practical example of personalized medicine in COS in women with PCOS. The internally validated approach may support individualized rFSH dosing during COS and serve as a basis for future development of decision support tools in this specific population. Full article

Backgrounds: Premature ovarian insufficiency (POI) is a clinical syndrome characterized by premature ovarian dysfunction, amenorrhea, and infertility. Ferulic acid (FA) is a prominent bioactive phenolic compound derived from traditional Chinese herbs Angelica sinensis (Oliv.) Diels and Ligusticum chuanxiong Hort. These herbs are commonly used to treat gynecological disorders including menstrual irregularities and infertility, and are known to modulate endoplasmic reticulum (ER) stress. However, the therapeutic potential and molecular mechanisms of FA in the context of POI remain largely unexplored. This study aimed to investigate the protective effects of FA against POI and to elucidate the underlying pharmacological mechanisms. Methods: In vivo, a mouse model of POI was established via a single intraperitoneal injection of cyclophosphamide (CTX; 120 mg/kg), and using FA for 28 days of continuous gavage to observe its therapeutic effect. Ovarian function and pathological changes were assessed by hormone levels, follicle development and oxidative stress (OS) level. In vitro, the effects of FA were examined using 4-hydroperoxy cyclophosphamide (4-OHCP)-treated KGN granulosa cells. Transcriptome sequencing, molecular docking, and molecular dynamics simulations were employed to identify potential targets of FA. Results: Our findings demonstrated that FA administration helped preserve regular estrous cycles, promoted follicle development and hormone secretion, and attenuated OS in both ovarian tissue and granulosa cells (GCs). Transcriptomic profiling combined with molecular docking and molecular dynamics simulations suggested that FA potentially targets key ER stress proteins, specifically Grp78 and Perk. Further in vivo and in vitro experiments confirmed that FA alleviates ER stress by inhibiting the overactivation of the Perk/eIF2α/ATF4/CHOP signaling pathway. Notably, the protective effects of FA were comparable to those of the ER stress inhibitor 4-Phenylbutyric acid (4-PBA) and were reversed by the ER stress activator tunicamycin (TM). Additionally, FA downregulates ERO1α expression, further blocking secondary oxidative damage triggered by ER stress. In KGN cells, FA significantly inhibits 4-OHCP-induced apoptosis and upregulates the anti-apoptotic proteins BCL-2 and BCL-xL, exhibiting efficacy similar to 4-PBA. Conclusions: FA improves ovarian function in CTX-induced POI by coordinately regulating OS and ER stress, inhibiting the Perk/eIF2α/ATF4/CHOP pathway, and suppressing GC apoptosis. These findings provide experimental evidence supporting FA as a potential therapeutic candidate for POI. Full article

Heat stress (HS) occurs when animals are unable to effectively dissipate excess body heat, leading to increased core temperature and physiological imbalance. In mammals, HS negatively affects female reproduction. Infertility associated with HS is well documented in swine and is increasingly recognized in other mammals, including humans. HS disrupts several systemic processes that are essential for normal reproductive function, including endocrine regulation, nutrient metabolism, immune activity, and intestinal barrier integrity. Reduced feed intake and changes in metabolic hormones such as insulin and prolactin can impair ovarian function. Increased intestinal permeability during HS may allow bacterial endotoxins to enter the bloodstream, triggering inflammation that further compromises reproductive physiology. At the ovarian level, HS alters key cellular pathways involved in cell survival and metabolism, including Janus Kinase/Signal Transducer and Activator of Transcription (JAK–STAT), Phosphoinositide 3-Kinase/Protein Kinase B (PI3K/AKT), oxidative stress responses, autophagy, apoptosis, and heat shock protein expression. These changes disrupt follicular development, hormone production, oocyte quality, and corpus luteum function, resulting in reduced conception rates and increased embryonic loss. This review summarizes current knowledge of systemic and ovarian mechanisms by which HS impairs female reproduction in pigs and identifies areas requiring further investigation to improve fertility under increasing environmental temperatures. Full article

Ovarian follicular development determines the egg-laying performance in chickens. Besides hormonal signaling, epigenetic and post-transcriptional regulators, long non-coding RNAs (lncRNAs) also play a vital role in follicular development. We previously identified that RAR-related orphan receptor B-intronic transcript 1 (RORB-IT1), a novel lncRNA located in the intron of RORB, was differentially expressed in chicken pre-hierarchical and hierarchical follicular granulosa cells (Post-GCs). However, it remains unknown whether RORB-IT1 participates in regulating the development of chicken ovarian follicles. In this study, we further characterized the expression pattern of RORB-IT1 and explored its role in regulating the progesterone synthesis, proliferation and apoptosis of chicken Post-GCs. The results showed that RORB-IT1, with a full length of 383 bp, exhibits a uniform distribution in both the cytoplasm and nucleus of chicken Post-GCs. RORB-IT1 was specifically expressed in Post-GCs and upregulated by follicle-stimulating hormone (FSH), progesterone (P4) and estradiol (E2) in a dose-dependent manner. Functionally, RORB-IT1 promoted P4 synthesis and proliferation, while inhibiting the apoptosis of Post-GCs. Furthermore, we demonstrated that RORB-IT1 encoded a functional micropeptide exhibiting dual localization in both cytoplasmic and nuclear compartments. This micropeptide enhanced progesterone synthesis and proliferation, but paradoxically induced the apoptosis of Post-GCs when overexpressed independently. Collectively, this study uncovered the expression pattern and function of RORB-IT1 in chicken Post-GCs and provided a theoretical basis for improving the egg-laying performance in chickens. Full article

Precise regulation of ovarian glucose metabolism and steroidogenesis is pivotal for the reproductive success of seasonal breeders. This study investigated seasonal variations in ovarian glucose metabolism and its association with follicular development and steroidogenesis in wild ground squirrels (Spermophilus dauricus). Results showed that ovarian weight and volume, and serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), 17β-estradiol, and progesterone were significantly higher in the breeding season (BS) than in the non-breeding season (NBS). Ovarian glycogen content was elevated in the BS, whereas circulating glucose levels decreased remarkably. Histologically, the BS ovaries contained follicles at all developmental stages (primary to Graafian) and corpora lutea, while corpora lutea were absent in the NBS. Integrated transcriptomic and metabolomic analyses revealed upregulated glycogen synthesis, glycolytic pathways, and altered steroidogenic metabolites in the BS. Quantitative real-time PCR (qRT-PCR) confirmed higher expression of glucose transporter 1 (GLUT1), glucose metabolism-related enzymes (G6PD, PFKFB3, PFKM), glycogen synthase (GYS), and steroidogenic factors (StAR, P450scc, P450c17, 3β-HSD, P450arom) in the BS, whereas glycogen synthase kinase-3β (Gsk-3β) was upregulated in the NBS. Immunohistochemistry demonstrated colocalization of steroidogenic and glucose-metabolizing enzymes in granulosa and theca cells, and correlation analyses confirmed positive associations between glucose metabolism, steroidogenesis, and ovarian weight. Collectively, these findings indicate that enhanced ovarian glucose metabolism in the BS is tightly coupled with elevated steroidogenesis, synergistically promoting seasonal follicular development and ovulatory competence in this species. Full article

With increasing life expectancy driven by rapid biomedical science advancement, reproductive longevity has become a key concept in women’s health. Preventing reproductive senescence is important not only to extend fertility potential but also to preserve endocrine health, enhance quality of life, and promote healthy aging. The end of ovarian function and fertility is symbolized by menopause, as the most eminent index of reproductive aging. Hormone replacement therapy (HRT) remains the mainstay for managing menopausal symptoms. However, as the use of HRT is often limited, there is a need for safe and effective alternatives. This narrative review summarizes current and emerging approaches targeting different stages of reproductive aging. Both hormonal and non-hormonal therapies for vasomotor and genitourinary symptoms are discussed alongside developing fertility preservation techniques, including oocyte vitrification, ovarian tissue cryopreservation, in vitro follicle maturation, and artificial ovary engineering. Furthermore, evolving and experimental ovarian regenerative strategies, such as stem cell transplantation, intraovarian platelet-rich plasma (PRP) injections, antioxidants, metabolic modulators, telomerase activators, and stem cell-derived extracellular vesicles, offer new prospects for delaying or reversing ovarian aging. Overall, personalized regenerative strategies and innovative solutions may reshape the future of women’s reproductive health and longevity. Full article

The Transforming Growth Factor-β (TGF-β) superfamily comprises highly conserved cytokines that orchestrate key cellular functions, including proliferation, differentiation, and apoptosis. Within the ovary, TGF-β family members serve as pivotal regulators of folliculogenesis, exerting stage-specific actions from embryonic germ cell development to advanced follicular maturation. During fetal development, activins and SMAD-dependent signaling pathways are essential for primordial germ cell proliferation, survival, and the breakdown of germ cell cysts, enabling the establishment of the primordial follicle pool. Throughout folliculogenesis, TGF-β supports follicle activation, promotes the transition from dormant to growing follicles, stimulates granulosa cell proliferation, sustains follicular viability, and modulates steroidogenesis through theca cell regulation. Notably, anti-müllerian hormone, a TGF-β family member, plays a central role in inhibiting premature follicle recruitment and serves as a key biomarker of ovarian reserve. Dysregulation of TGF-β signaling contributes to various ovarian disorders, including polycystic ovary syndrome and premature ovarian insufficiency. A deeper understanding of these complex signaling networks is critical for identifying novel therapeutic targets and advancing clinical interventions in female reproductive pathologies. This review provides an integrated overview of the roles of the TGF-β superfamily in ovarian physiology and its contributions to disease development. Full article

Follicle-stimulating hormone receptor (FSHR) is expressed on the plasma membrane of granulosa cells in the ovarian follicles. FSHR is involved in the development and maturation of Graafian follicles, along with granulosa proliferation and estrogen synthesis. There are two well-characterized non-synonymous single-nucleotide gene polymorphisms in the exon 10 of the human FSHR gene, namely rs6165 (c.919G>A, Ala307Thr) and rs6166 (c.2039A>G, Ser680Asn). Recent research clarifies the association of rs6165/rs6166 with susceptibility to infertility-associated ovarian diseases, ranging from polycystic ovarian syndrome, premature ovarian insufficiency, endometriosis, to ovarian cancer, along with response/resistance to ovulation induction/ovarian stimulation with clomiphene citrate, letrozole, metformin, FSH preparations, and adjunctive growth hormone in infertility treatment. This narrative review aims to update the knowledge on the relationship among rs6165/rs6166, infertility etiology, and differential responses to oral ovulation induction agents, FSH preparations, and adjunctive growth hormone. The re6165/rs6166 genotype-guided choice of individualized ovulation stimulation preparations has great potential to reduce unexpected poor or high ovarian responses in ovulation induction and ovarian stimulation and improve clinical outcomes in reproductive medicine. Current evidence is insufficient, and further studies are warranted to ascertain its potential for clinical implementation. Full article