Female Reproductive Aging Research Articles

7395 Developmental Programming: Adverse Effects Of Prenatal Exposure To A Real-Life Environmental Chemical Mixture Via Biosolids On Ovarian Folliculogenesis In Adult Sheep

Abstract Disclosure: Y. Zhou: None. K.M. Halloran: None. M. Bellingham: None. N.P. Evans: None. R.G. Lea: None. K.D. Sinclair: None. V. Padmanabhan: None. The ovarian capacity to provide fertilizable oocytes, regulate folliculogenesis as well as activate and progress primordial follicles into preovulatory follicles are key contributing factors to female fertility and reproductive aging. In sheep, as in humans, while genetics play a role in establishing the ovarian reserve during fetal development, developmental insults such as inappropriate exposure to native steroids or environmental chemicals (ECs) can adversely impact the establishment of the ovarian reserve and, additionally can affect folliculogenesis. Considering humans are exposed to multiple ECs simultaneously which could have additive, synergistic, or antagonistic effects, real-life EC exposure models are needed to assess risks posed by EC exposure. Offspring from sheep grazed on biosolids-treated pasture offers one such real-life exposure model. Studies with day 140 fetuses found maternal exposure to a real-life EC mixture via biosolids increased the proportion of unhealthy transitory follicles (Lea et al., Sci Rep. 2016;6:22279). The present study tested if biosolids exposure during fetal life would impact folliculogenesis, follicle activation and follicle atresia during their adult life. Ovaries were derived from adult EasyCare ewes (age 31.4 ± 0.5 months) whose mothers were grazed on biosolids-treated (BTP, n=10) or inorganic fertilizer-treated (Control, n=10) pastures from preconception through to birth. Ovarian morphometry was undertaken to assess the distribution and health status of follicles. Follicular atresia was evaluated via the expression of Caspase-3, an apoptosis marker. Data analysis utilized Student's t-test for normally distributed variables and Mann-Whitney U tests for non-parametric comparisons. There were no differences in the absolute counts or the percentages of follicle classes at all stages of folliculogenesis, the density of primordial follicles in cortical tissue, or the follicular activation rate. An increase in the percentage of unhealthy activated follicles (post-primordial) was noted in the BTP group (p = 0.014), predominantly in the transitory stage (p = 0.021). Consistent with this, a higher density of Caspase-3 positive primary follicles was observed in the BTP group (p = 0.033). These findings indicate the adverse impacts of fetal exposure to an EC mixture via maternal biosolid exposure on the survival of early-stage activated follicles in adult sheep. The lack of difference in ovarian reserve between the control and BTP groups suggests compensatory mechanisms may be in place to prevent premature depletion of the ovarian reserve. Whether EC mixture exposure via biosolids also has an adverse effect on the quality of the surviving activated follicles remains to be determined. Funding source: NIH R01 ES030374. Presentation: 6/3/2024

A maternal germline mutator phenotype in a family affected by heritable colorectal cancer.

Variation in DNA repair genes can increase cancer risk by elevating the rate of oncogenic mutation. Defects in one such gene, MUTYH, are known to elevate the incidence of colorectal cancer in a recessive Mendelian manner. Recent evidence has also linked MUTYH to a mutator phenotype affecting normal somatic cells as well as the female germline. Here, we use whole genome sequencing to measure germline de novo mutation rates in a large extended family containing both mothers and fathers who are affected by pathogenic MUTYH variation. By developing novel methodology that uses siblings as "surrogate parents" to identify de novo mutations, we were able to include mutation data from several children whose parents were unavailable for sequencing. In the children of mothers affected by the pathogenic MUTYH genotype p.Y179C/V234M, we identify an elevation of the C>A mutation rate that is weaker than mutator effects previously reported to be caused by other pathogenic MUTYH genotypes, suggesting that mutation rates in normal tissues may be useful for classifying cancer-associated variation along a continuum of severity. Surprisingly, we detect no significant elevation of the C>A mutation rate in children born to a father with the same MUTYH genotype, and we similarly find that the mutator effect of the mouse homolog Mutyh appears to be localized to embryonic development, not the spermatocytes. Our results suggest that maternal MUTYH variants can cause germline mutations by attenuating the repair of oxidative DNA damage in the early embryo.

O-GlcNAc participates in the meiosis of aging oocytes by mediating mitochondrial function.

With an increase in the mean age at parturition worldwide, female reproductive aging has become a key health problem. Advanced maternal age is reflected by decreased oocyte quality; however, the molecular mechanisms of oocyte aging are uncharacterized. O-linked N-acetylglucosamine (O-GlcNAc), a dynamic posttranslational modification, plays a critical role in the development of many age-related diseases, yet it remains unclear whether and how O-GlcNAc participates in oocyte aging. Here, we found that global O-GlcNAc was elevated in normal biological aging mice oocytes (32-34 weeks) which were characterized by meiotic maturation failure and impaired mitochondrial function. Specifically, O-GlcNAc targeted the mitochondrial fission protein dynamic-related protein 1 (DRP1) to meditate mitochondrial distribution in the process of aging. Using the O-GlcNAcase (OGA) pharmacological inhibitor Thiamet-G and OGA knockdown (OGA-KD) to mimic the age-related high O-GlcNAc in young oocytes from 6-8 week-old mice mimicked the phenotype of oocyte aging. Moreover, reducing O-GlcNAc levels in aging oocytes restored spindle organization to improve oocyte quality. Our results demonstrate that O-GlcNAc is a key regulator of meiotic maturation that participates in the progression of oocyte aging.

Maintaining mitochondrial DNA copy number mitigates ROS-induced oocyte decline and female reproductive aging

Oocytes play a crucial role in transmitting maternal mitochondrial DNA (mtDNA), essential for the continuation of species. However, the effects of mitochondrial reactive oxygen species (ROS) on mammalian oocyte maturation and mtDNA maintenance remain unclear. We investigated this by conditionally knocking out the Sod2 gene in primordial follicles, elevating mitochondrial matrix ROS levels from early oocyte stages. Our data indicates that reproductive aging in Sod2 conditional knockout females begins at 6 months, with oxidative stress impairing oocyte quality, particularly affecting OXPHOS complex II and mtDNA-encoded mRNA levels. Despite unchanged mtDNA mutation load, mtDNA copy numbers exhibited significant variations. Strikingly, reducing mtDNA copy numbers by reducing mtSSB protein, crucial for mtDNA replication, accelerated reproductive aging onset to three months, underscoring the critical role of mtDNA copy number maintenance under oxidative stress conditions. This research provides new insights into the relationship among mitochondrial ROS, mtDNA, and reproductive aging, offering potential strategies for delaying aging-related fertility decline.

Late Reproduction Is Associated With Extended Female Survival But Not With Familial Longevity

(Abstracted from Reprod Biomed Online 2024;49(3):104073) Reproductive health in women is a broad term that can encompass health from birth such as being born with a complete set of oocytes, to fertility, pregnancy, deterioration of quantity, and quality of oocytes, to postmenopausal health. Although there are many available data on reproductive health, the relationship between female reproductive health and aging and somatic health and aging is not well characterized.

Early menarche and childbirth accelerate aging-related outcomes and age-related diseases: Evidence for antagonistic pleiotropy in humans.

Aging can be understood as a consequence of the declining force of natural selection with age. Consistent with this the antagonistic pleiotropic theory of aging suggests that aging results from the trade-offs that promote early growth and reproduction. However, evidence for antagonistic pleiotropy in humans is largely lacking. Using Mendelian Randomization (MR), we demonstrated that later ages of menarche or first childbirth were genetically associated with longer parental lifespan, decreased frailty index, slower epigenetic aging, later menopause, and reduced facial aging. Moreover, later menarche or first childbirth were also genetically associated with a lower risk of several age-related diseases, including late-onset Alzheimer's disease (LOAD), type 2 diabetes, heart disease, essential hypertension, and chronic obstructive pulmonary disease (COPD). We validated the associations between the age of menarche, childbirth, and the number of childbirths with several age-related outcomes in the UK Biobank by conducting regression analysis of nearly 200,000 subjects. Our results demonstrated that menarche before the age 11 and childbirth before 21 significantly accelerated the risk of several diseases, and almost doubled the risk for diabetes, heart failure, and quadrupled the risk of obesity, supporting the antagonistic pleiotropy theory. We identified 128 significant single nucleotide polymorphisms (SNPs) that influenced age-related outcomes, some of which were involved in known longevity pathways, including IGF1, growth hormone, AMPK, and mTOR signaling. Our study also identified higher BMI as a mediating factor in causing the increased risk of certain diseases, such as type 2 diabetes and heart failure, in women with early menarche or early pregnancy, emphasizing the importance of the thrifty gene hypothesis in explaining in part the mechanisms behind antagonistic pleiotropy. Our study highlights the complex relationship between genetic legacies and modern diseases, emphasizing the need for gender-sensitive healthcare strategies that consider the unique connections between female reproductive health and aging.

NAD+ Metabolism and Mitochondrial Activity in the Aged Oocyte: Focus on the Effects of NAMPT Stimulation.

The ovary experiences an age-dependent decline starting during the fourth decade of life. Ovarian aging is the predominant factor driving female reproductive aging. Modern trend to postpone childbearing age contributes to reduced fertility and natality worldwide. Recently, the beneficial role of NAD+ precursors on the maintenance of oocyte competence and female fertility affected by aging has emerged. Nevertheless, age-related changes in NAD+ regulatory network have not been investigated so far. In this context, our goal was to investigate changes induced by the aging process in the expression level of genes participating in NAD+ biosynthetic and NAD+ consuming pathways and in the cellular bioenergetics in the mouse oocyte. From Ingenuity Pathway Analysis (IPA) it emerged that aging caused the downregulation of all cellular pathways for NAD+ synthesis (Kynurenine pathway, Preiss-Handler pathway and NAD+ salvage pathway) and deeply influenced the activity of NAD+-dependent enzymes, i.e. PARPs and SIRTs, with effects on many cellular functions including compromised ROS detoxification. Considering that NAMPT, the rate-limiting enzyme of NAD+ salvage pathway, was deregulated, aged oocytes were matured in the presence of P7C3, NAMPT activator. P7C3 improved spindle assembly and mitochondrial bioenergetics and reduced mitochondrial proton leak. Moreover, P7C3 influenced gene expression of NAD+ regulatory network, with Sirt1 as the central node of IPA-interfered target gene network. Finally, P7C3 effectively counteracted oocyte alterations induced by exposure to oxidative stress. Our study contributes to establish effective NAD+ boosting interventions to alleviate the effects of advanced maternal age on fertility and explore their potential in redox-related fertility disorders.

Exploring the anti-ovarian aging mechanism of He's Yangchao formula: Insights from multi-omics analysis in naturally aged mice

BackgroundThe rapid acceleration of female reproductive aging has become a major public health concern. He's Yangchao formula (HSYC), a compound comprising eight herbs, has demonstrated efficacy in enhancing ovarian function. Thus, an in-depth study of its anti-ovarian aging mechanism is required. PurposeTo evaluate the anti-ovarian aging effect of HSYC in naturally aged mice and investigate the underlying mechanism by analyzing the gut microbiota (GM), metabolome, and transcriptome. MethodsYoung and advanced maternal age (AMA) mice were selected for this study. Hematoxylin and eosin staining, fluorescence staining, western blotting, and qPCR analyses were used to detect the phenotypes associated with ovarian aging. Subsequently, analyses of the GM, transcriptome, and metabolome analyses were performed to explore the potential mechanisms of action of HSYC. Finally, in vivo and in vitro experiments were performed to verify potential therapeutic mechanisms. ResultsHSYC promoted follicular development in AMA mice and ameliorated age-related mitochondrial dysfunction, apoptosis, and defects in DNA damage repair. GM analysis revealed that HSYC treatment significantly increased the abundance of Akkermansia and Turicibacter. Transcriptome and metabolome analyses showed that HSYC might mitigate ovarian aging by regulating metabolic pathways, amino acid metabolism, glutathione metabolism, and the synthesis of pantothenic acid and coenzyme A. Combined transcriptomic and metabolomic analyses identified the glutathione metabolic pathway as the key pathway through which HSYC counteracts ovarian aging. Additional experimental verification confirmed that HSYC upregulated the glutathione metabolic genes GPX8, GSTA1, and GSTA4, increased glutathione-related products (GSH), and reduced ROS levels. ConclusionsHSYC exerts beneficial therapeutic effects on ovarian aging by regulating multiple endogenous metabolites, targets, and metabolic pathways, with an emphasis on its anti-ovarian aging effects through the glutathione metabolic pathway. These findings underscore the innovative potential of HSYC in addressing ovarian aging and offer a novel therapeutic approach that targets multiple biological pathways to improve the reproductive health of women with AMA..

P-370 The age-associated increase in ovarian stiffness compromises follicle development and induces changes in the follicles’ transcriptome, resulting in poor-quality oocytes

Abstract Study question Does the age-associated increase in ovarian stiffness trigger the decline in oocyte quantity and quality observed in women of advanced maternal age? Summary answer An encapsulated in vitro follicle culture mimicking ovarian biomechanics revealed that age-associated increase in stiffness impacts follicle growth, modulates follicles’ transcriptome and reduces oocyte quality. What is known already Female reproductive aging is characterized by a progressive decline in oocyte quality and quantity, resulting in sub-fertility. We recently discovered that with aging the mouse ovary assumes a pro-fibrotic milieu which induces ovarian stiffness. Moreover, human ovaries also become stiffer with aging; however, it is not known whether this age-associated increase in stiffness impacts ovarian function. The present study aims to examine whether stiffness is a novel mechanism that mediates the age-associated progressive decline in oocyte quality and how stiffness affects the transcriptome of growing follicles, resulting in poor-quality oocytes. Study design, size, duration We used an in vitro alginate-encapsulated follicle culture to mimic young and old environments in which follicles grow. Alginate hydrogel synthesis replicated the soft (0.5% - 1.79±0.08 kPa) and stiff (2% - 4.56±2.03 kPa) environments of young and aged ovaries, respectively. Mouse secondary follicles were cultured in 0.5 or 2% alginate and used for i) long-term culture (day 0-10) to evaluate follicle development and oocyte quality; ii) short-term culture (hour 0-24) to investigate follicles’ transcriptome. Participants/materials, setting, methods During the long-term culture, markers of follicle development were evaluated (n = 31 follicles), including: follicle size, estradiol production (ELISA), cell death (cleaved-caspase3,CC3; immunohistochemistry). At D10, oocyte quality was inspected on isolated oocytes. For the short-term culture experiment, 32 follicles were analyzed by RNAsequencing at 3h (baseline) and 24h. We compared 3h and 24h gene expression (DESeq2,R/Bioconductor) in 0.5% and 2%. Significant differences reported at padj<0.05 and log2FoldChange±2. Two mice strains (CB6F1;CD1) were used in all experiments. Main results and the role of chance Follicles cultured in stiff environment showed a significant reduction in follicle size compared to follicles cultured in soft environment (0.5% 226.9±17.4um, 2% 160.8±9.9um; p < 0.0001). These size differences suggest that granulosa cells are not proliferating in a stiff environment. Estradiol production was reduced in follicles cultured at 2% (0.5% 11.3±15.9ng/ml, 2% 0.3±0.5ng/ml, p = 0.296), while CC3 intensity was increased (CC3 staining intensity/area, 0.5% 20.4±5.8a.u., 2% 27.1±4.3a.u., p < 0.05), suggesting that the stiff environment impacts granulosa cell viability. Oocyte quality significantly declined in follicles cultured in 2%, with 68.9±16.8% of the oocytes degenerated, compared to 23.6±9.2% in 0.5% alginate. The use of two different mice strains yielded comparable results. Using RNAsequencing analysis, we found 1033 differentially expressed genes (DEGs) between 3h and 24h of culture in 2% alginate, mostly involved in apoptosis, inflammation and collagen processes, biological pathways typically associated with aging. The 64% of those DEGs were upregulated at 24h. Conversely, the 1295 DEGs (61% upregulated at 24h) detected comparing 3h and 24h in 0.5% alginate were relate to metabolism, cell cycle and development pathways, biological processes associated to the normal behavior of growing follicles. These differences in gene expression suggest an early-response in the transcriptome of follicles cultured in a stiff environment. Limitations, reasons for caution The stiffness of the alginate gels was based on whole ovary biomechanics; future investigations are needed to measure each follicle-stage-specific stiffness. The changes in follicles’ transcriptome in the stiff environment were evaluated only in short-term culture. This study utilizes in vitro approaches, in vivo modulation of stiffness is currently undergoing. Wider implications of the findings Increased ovarian stiffness is observed in conditions such as aging or ovaries exposed to cancer treatments. Studying how stiffness impacts oocyte quality will allow the development of suitable in vitro systems to support human folliculogenesis and in vivo approaches to modulate biomechanics of the ovary, preserving female fertility. Trial registration number not applicable

Gonadotropin elevation is ootoxic to ovulatory oocytes and inhibits oocyte maturation, and activin decoy receptor ActRIIB:Fc therapeutically restores maturation

BackgroundElevated FSH often occurs in women of advanced maternal age (AMA, age ≥ 35) and in infertility patients undergoing controlled ovarian stimulation (COS). There is controversy on whether high endogenous FSH contributes to infertility and whether high exogenous FSH adversely impacts patient pregnancy rates.MethodsThe senescence-accelerated mouse-prone-8 (SAMP8) model of female reproductive aging was employed to assess the separate impacts of age and high FSH activity on the percentages (%) of viable and mature ovulated oocytes recovered after gonadotropin treatment. Young and midlife mice were treated with the FSH analog equine chorionic gonadotropin (eCG) to model both endogenous FSH elevation and exogenous FSH elevation. Previously we showed the activin inhibitor ActRIIB:Fc increases oocyte quality by preventing chromosome and spindle misalignments. Therefore, ActRIIB:Fc treatment was performed in an effort to increase % oocyte viability and % oocyte maturation.ResultsThe high FSH activity of eCG is ootoxic to ovulatory oocytes, with greater decreases in % viable oocytes in midlife than young mice. High FSH activity of eCG potently inhibits oocyte maturation, decreasing the % of mature oocytes to similar degrees in young and midlife mice. ActRIIB:Fc treatment does not prevent eCG ootoxicity, but it restores most oocyte maturation impeded by eCG.ConclusionsFSH ootoxicity to ovulatory oocytes and FSH maturation inhibition pose a paradox given the well-known pro-growth and pro-maturation activities of FSH in the earlier stages of oocyte growth. We propose the FOOT Hypothesis (“FSH OoToxicity Hypothesis), that FSH ootoxicity to ovulatory oocytes comprises a new driver of infertility and low pregnancy success rates in DOR women attempting spontaneous pregnancy and in COS/IUI patients, especially AMA women. We speculate that endogenous FSH elevation also contributes to reduced fecundity in these DOR and COS/IUI patients.Restoration of oocyte maturation by ActRIB:Fc suggests that activin suppresses oocyte maturation in vivo. This contrasts with prior studies showing activin A promotes oocyte maturation in vitro. Improved oocyte maturation with agents that decrease endogenous activin activity with high specificity may have therapeutic benefit for COS/IVF patients, COS/IUI patients, and DOR patients attempting spontaneous pregnancies.

Effects of Oral Zinc Supplementation on Early Embryonic Development and Neonates of Aged Female Albino Mice

Female reproductive aging is a normal phase of life that eventually leads to menopause and reproductive senescence. The current experimental investigation was intended to study zinc supplementation effects on early embryonic development and neonates in 26-28 weeks old female mice. In this investigation, 80 mature female mice were used that were divided into two groups of forty each. Two control groups received distilled water, while two Zn groups were given 0.115 mg/kg/day Zn orally daily during 2-3 estrous cycles. The female mice were all mated with adult males. Twenty female mice from both the control and Zn groups were euthanized by CO2 gas inhalation, and then a longitudinal incision in the abdomen of each female mouse was performed and uterine horns and oviducts were detached from the body in order to obtain two-cell embryos. On the other hand, 20 pregnant mice from each group were permitted to complete their pregnancy until birth and then their neonates were collected for macroscopic examination. The findings showed that the Zn supplementation significantly (P≤0.01) improved the mean embryonic development and the quality of 2-cell stage embryo grade A. Whereas, it decreased the mean embryonic development of 2-cell stage embryo grade D in aged female mice significantly (P≤0.01) in comparison with aged control groups. Also, the count and quality of neonates from Zn-treated aged female mice enhanced significantly (P≤0.01) as compared to non-treated aged female mice. It was concluded from these findings that the Zn can improve embryonic development and neonate count and quality in aged mice.

A Molecular Perspective and Role of NAD+ in Ovarian Aging.

The decline in female fecundity is linked to advancing chronological age. The ovarian reserve diminishes in quantity and quality as women age, impacting reproductive efficiency and the aging process in the rest of the body. NAD+ is an essential coenzyme in cellular energy production, metabolism, cell signaling, and survival. It is involved in aging and is linked to various age-related conditions. Hallmarks associated with aging, diseases, and metabolic dysfunctions can significantly affect fertility by disturbing the delicate relationship between energy metabolism and female reproduction. Enzymes such as sirtuins, PARPs, and CD38 play essential roles in NAD+ biology, which actively consume NAD+ in their enzymatic activities. In recent years, NAD+ has gained much attention for its role in aging and age-related diseases like cancer, Alzheimer's, cardiovascular diseases, and neurodegenerative disorders, highlighting its involvement in various pathophysiological processes. However, its impact on female reproduction is not well understood. This review aims to bridge this knowledge gap by comprehensively exploring the complex interplay between NAD+ biology and female reproductive aging and providing valuable information that could help develop plans to improve women's reproductive health and prevent fertility issues.

HUC-MSC Combined with DHEA Alleviates Ovarian Senescence in Naturally Aging Mice through Enhancing Antioxidant Capacity and Inhibiting Inflammatory Response.

The ovary is an important organ for women to maintain reproductive and endocrine functions. Ovarian aging can lead to female reproductive aging, which is a key factor causing rapid aging of the female body. Umbilical cord-derived MSCs (UC-MSCs) play a therapeutic role in various degenerative diseases. Dehydroepiandrosterone (DHEA) is widely used in the treatment of reversing oocyte quality. However, it is unclear whether UC-MSCs combined with DHEA supplementation can improve ovarian senescence in naturally aging mice. To address this question, we studied the influence of the combination of human UC-MSCs (hUC-MSCs) and DHEA on ovarian morphology and function in naturally aging mice. The results showed a significant augmentation in the number of primary follicles, as well as a significant upregulation of estradiol (E2), follicle-stimulating hormone (FSH), and anti-Mullerian hormone (AMH) hormone levels, and a significant increase in survival rate in naturally aging mice treated by hUC-MSCs and DHEA. Moreover, the combination of hUC-MSCs and DHEA significantly reduced the reactive oxygen species (ROS) level and downregulated the expression levels of proinflammatory factors IL-6, IL-18, and TNF-α. Furthermore, the PI3K/AKT/mTOR pathway was inhibited. Conclusively, the combination therapy of hUC-MSC + DHEA contributed to restore ovarian function in aging mice and extend their lifespan by restoring hormone levels and inhibiting inflammatory factors.

Kuntai capsule attenuates premature ovarian insufficiency by activating the FOXO3/SIRT5 signaling pathway in mice: A comprehensive study using UHPLC-LTQ-Orbitrap and integrated pharmacology

Ethnopharmacological relevanceClassical prescriptions are not only a primary method of clinical treatment in traditional Chinese medicine (TCM) but also represent breakthroughs in the inheritance and development of this field. Kuntai capsule (KTC), a formulation based on a classical prescription, comprises six TCMs: Rehmanniae Radix Praeparata, Coptidis Rhizoma, Paeoniae Radix Alba, Scutellariae Radix, Asini Corii Colla, and Poria. This formulation possesses various beneficial effects, such as nourishing yin and blood, clearing heat and purging fire, and calming the nerves and relieving annoyance. The investigation of the efficacy and mechanism of KTC in regulating anti-aging factors in the treatment of premature ovarian insufficiency (POI) is not only a prominent topic in classical prescription research but also a crucial issue in the treatment of female reproductive aging using TCM. Aim of the studyTo evaluate the therapeutic effect of KTC on POI and its underlying mechanism. Materials and methodsHealthy and specific pathogen-free (SPF) female Kunming mice aged 6–8 weeks were selected. After acclimatization, the mice were randomly divided into a control, model, and high, middle, and low dose groups of KTC (1.6, 0.8, and 0.4 mg/kg, respectively). Except for the control group, the animals in the other groups were administered a single intraperitoneal injection of 120 mg/kg cyclophosphamide and 30 mg/kg Busulfan to induce the model of POI. After modeling, the mice were treated with the corresponding drugs for 7 days. Serum and ovarian tissues were collected, and the levels of serum follicle-stimulating hormone (FSH), estradiol (E2), and superoxide dismutase 2 (SOD2) were determined using enzyme-linked immunosorbent assay (ELISA). The chemical composition of KTC was characterized and analyzed using ultra-high-pressure liquid chromatography-linear ion trap-Orbitrap tandem mass spectrometry. A “drug-component-target-pathway-disease” network was constructed using network pharmacology research methods to identify the key active components of KTC in treating POI and to elucidate its potential mechanism. The protein expression of the FOXO3/SIRT5 pathway was detected by western blotting. ResultsCompared to the model group, the high-dose group of KTC showed a significant increase in ovarian index, significant increase in levels of E2 and SOD2, and a significant decrease in FSH levels. Through systematic analysis of the chemical constituents of KTC, 69 compounds were identified, including 7 organic acids, 14 alkaloids, 28 flavonoids, 15 terpenoids, 2 lignans, 2 phenylpropanoids, and 1 sugar. Based on network pharmacology research methods, it was determined that KTC exerts its therapeutic effect on POI through multiple components (paeoniflorin and malic acid), multiple targets (FOXO3 and SIRT5), and multiple pathways (prolactin signaling pathway, longevity regulating pathway, and metabolic pathways). The accuracy of the network pharmacology prediction was further validated by detecting the protein expression of SIRT5 and FOXO3a, which showed a significant increase in the middle and high-dose groups of KTC compared to the model group. ConclusionsKTC may effectively treat POI through a multi-component, multi-target, multi-pathway approach, providing an experimental basis for using KTC based on classical prescriptions in the treatment of POI.

DNA methylation as a window into female reproductive aging.

People with ovaries experience reproductive aging as their reproductive function and system declines. This has significant implications for both fertility and long-term health, with people experiencing an increased risk of cardiometabolic disorders after menopause. Reproductive aging can be assessed through markers of ovarian reserve, response to fertility treatmentor molecular biomarkers, including DNA methylation. Changes in DNA methylation with age associate with poorer reproductive outcomes, and epigenome-wide studies can provide insight into genes and pathways involved. DNA methylation-based epigenetic clocks can quantify biological age in reproductive tissues and systemically. This review provides an overview of hallmarks and theories of aging in the context of the reproductive system, and then focuses on studies of DNA methylation in reproductive tissues.

GENOMIC ARCHITECTURE OF FEMALE REPRODUCTIVE AGING

Abstract Female reproductive lifespan is characterised by declining ovarian reserve, but the underlying mechanism is poorly understood. Reproductive ageing is a multifactorial trait with both genetic and environmental modifiers. Our research uses genome-wide analyses to identify the genes and biological processes that govern female reproductive ageing. We have identified 290 genetic loci with relatively common variants (>0.1%) that are associated with timing of natural menopause, in a meta-analysis of >200,000 women in the ReproGen consortium. In combination these common variants explain around 12% of the variation in menopause timing. Women in the top 1% combined genetic risk centile for earlier menopause are approximately 5x more likely to have menopause before 40 years. A high genetic risk for earlier menopause in mothers, but not fathers, is also associated with increased de novo mutation rate in offspring. We assessed the role of rare (MAF<0.1%) protein-coding variants on ovarian function in data from 104,733 females in the UK Biobank using gene burden association tests. We identified nine genes with associations that passed our multiple testing threshold. Protein-truncating variants in ZNF518A were associated with earlier menopause (effect size 5.61 years, P=1.2x10-10), with an effect larger than for any previously reported gene or variant. Deleterious variants in SAMHD1 were associated with >1 year later menopause and were also a germline risk factor for cancer predisposition in males and females. Understanding the genetics of reproductive ageing is not only important for fertility, but also has implications for broader age-related health outcomes, such as cancer, diabetes and osteoporosis.

GENOMIC ARCHITECTURE OF FEMALE REPRODUCTIVE AGING

Abstract Female reproductive lifespan is characterised by declining ovarian reserve, but the underlying mechanism is poorly understood. Reproductive ageing is a multifactorial trait with both genetic and environmental modifiers. Our research uses genome-wide analyses to identify the genes and biological processes that govern female reproductive ageing. We have identified 290 genetic loci with relatively common variants (>0.1%) that are associated with timing of natural menopause, in a meta-analysis of >200,000 women in the ReproGen consortium. In combination these common variants explain around 12% of the variation in menopause timing. Women in the top 1% combined genetic risk centile for earlier menopause are approximately 5x more likely to have menopause before 40 years. A high genetic risk for earlier menopause in mothers, but not fathers, is also associated with increased de novo mutation rate in offspring. We assessed the role of rare (MAF<0.1%) protein-coding variants on ovarian function in data from 104,733 females in the UK Biobank using gene burden association tests. We identified nine genes with associations that passed our multiple testing threshold. Protein-truncating variants in ZNF518A were associated with earlier menopause (effect size 5.61 years, P=1.2x10-10), with an effect larger than for any previously reported gene or variant. Deleterious variants in SAMHD1 were associated with >1 year later menopause and were also a germline risk factor for cancer predisposition in males and females. Understanding the genetics of reproductive ageing is not only important for fertility, but also has implications for broader age-related health outcomes, such as cancer, diabetes and osteoporosis.

Polyamine metabolite spermidine rejuvenates oocyte quality by enhancing mitophagy during female reproductive aging.

Advanced age is a primary risk factor for female infertility due to reduced ovarian reserve and declining oocyte quality. However, as an important contributing factor, the role of metabolic regulation during reproductive aging is poorly understood. Here, we applied untargeted metabolomics to identify spermidine as a critical metabolite in ovaries to protect oocytes against aging. In particular, we found that the spermidine level was reduced in ovaries of aged mice and that supplementation with spermidine promoted follicle development, oocyte maturation, early embryonic development and female fertility of aged mice. By microtranscriptomic analysis, we further discovered that spermidine-induced recovery of oocyte quality was mediated by enhancement of mitophagy activity and mitochondrial function in aged mice, and this mechanism of action was conserved in porcine oocytes under oxidative stress. Altogether, our findings suggest that spermidine supplementation could represent a therapeutic strategy to ameliorate oocyte quality and reproductive outcome in cis-gender women and other persons trying to conceive at an advanced age. Future work is needed to test whether this approach can be safely and effectively translated to humans.

FEATURES OF MENOPAUSE MANAGEMENT AS AN AGING PREVENTION (review article)

Menopause is a physiological transition period in a woman’s life from the reproductive phase with regular ovulatory cycles and corresponding cyclic changes in the reproductive system to the postmenopausal state. The modern concept of female reproductive aging is to recognize the leading role of depletion of the ovarian follicular apparatus. Climacteric syndrome (CS) is the earliest and most common complication of the menopausal period. Most of the pathological manifestations that occur during peri- and postmenopausal periods are associated with an estrogen deficiency state and are subject to correction by hormone replacement therapy (HRT). In addition, in postmenopause the frequency of many diseases that reflect the biological aging of the body increases. Therefore, in order to develop optimal HRT regimens and understand the role of a rational lifestyle in the correction of these manifestations, it is necessary to consider the evolution of views on the menopause in general and HRT in particular. Until now, there has been no consensus regarding the tactics of a differentiated approach when prescribing HRT, taking into account existing systemic disorders in women with a history of “diseases of civilization.” Individualization of HRT in patients with a history of impaired reproductive function should be determined not only by the clinical variability of the manifestations of CS, but also taking into account the presence of extragenital pathology, which requires the implementation of our proposed diagnostic algorithm and the basis for the development of such a HRT strategy.

Rethinking advanced motherhood: a new ethical narrative

The aim of the study is to rethink the ethics of advanced motherhood. In the literature, delayed childbearing is usually discussed in the context of reproductive justice, and in relationship to ethical issues associated with the use and risk of assisted reproductive technologies. We aim to go beyond these more “traditional” ways in which reproductive ethics is framed by revisiting ethics itself through the lens of the figure of the so-called “older” mother. For this purpose, we start by exploring some of the deep seated socio-cultural discourses in the context of procreation: ageism, ableism and the widespread bias towards geneticism and pronatalism. Afterwards, we provide a critical overview of the key arguments against or in support of advanced motherhood. We then briefly discuss how entrenchment by both sides has produced an impasse in the debate on the ethics of advanced motherhood and proceed by arguing that it is fundamental to bring about a change in this narrative. For this purpose, we will revisit the feminist usage of the concept of vulnerability which will allow us both to criticize culturally prescribed norms about motherhood and to address the painful reality of age-related fertility decline. In the last section, we argue that instead of defining “older” motherhood as an ethical problem, we should problematize the fact that female reproductive ageing is an understudied and ill-sourced topic. We believe that allocating resources to research to better understand female reproductive ageing is not only ethically permissible, but might even be ethically desirable.