Role of oxidative stress in female reproduction

L-proline supplementation in the freezing medium enhances the viability and quality of bovine blastocysts after slow freezing and thawing

L-proline (Pro) is a natural amino acid with known antioxidant and cryoprotectant activity. This study aimed to assess the impact of Pro supplementation in freezing medium on blastocyst survival and quality. In vitro fertilization (IVF) was conducted using oocytes collected from Korean cattle, and Day 7 blastocysts were cryopreserved through slow freezing. Optimal post-thaw blastocyst survival was determined by adding various Pro concentrations to the freezing medium. Additionally, the effect of Sucrose (Suc) alone or in conjunction with Pro was evaluated. To assess blastocyst quality, we analyzed reactive oxygen species (ROS) levels, apoptosis, and gene expression in blastocysts that survived 24 h after slow freezing-thawing. The hatching rate at 72 h was significantly higher in the 0.3 M Pro group than that in the 0 M group (p = 0.0466). The hatching rates at 48 and 72 h were significantly higher in the Pro group than in the Suc and Suc + Pro groups (48 h: Suc, p = 0.0037; Suc + Pro, p = 0.0052; 72 h: Suc, p = 0.0024; Suc + Pro, p = 0.0009). ROS levels and the apoptosis index were significantly lower in the Pro group than in the Suc group (p = 0.0099, and 0.0098, respectively). Furthermore, mRNA expression of HSPA1A was significantly lower in the Pro and Suc + Pro groups than in the Suc group (p = 0.0074, and p = 0.01174, respectively). Additionally, GCLC mRNA expression was significantly higher in the Pro group than in the Suc group (p = 0.0308). These findings indicate that Pro supplementation in a slow freezing medium enhances the viability and quality of embryos.

Multigenerational exposure to trace concentrations of DDT residues in Wistar rats: Effects on biometric development and biochemical parameters

The Organochlorine Dichlorodiphenyltrichloroethane (DDT) and its residues, Dichlorodiphenyldichloroethane (DDD) and Dichlorodiphenyldichloroethylene (DDE), are Persistent Organic Pollutants (POPs) that bioaccumulate, persist in the environment, and magnify through the food chain. Chronic exposure is linked to oxidative stress and mitochondrial dysfunction, emphasizing the need to study its multigenerational impacts on health and development. This study investigated the effects of multigenerational exposure to DDT residues in Wistar rats. Pregnant females were provided water containing trace concentrations of p,p'-DDD (0.015 µM) and p,p'-DDE (0.006 µM) from the first day of gestation (PD0) until the end of the life cycle of two generations (F1 and F2). Biometric and biochemical evaluations were conducted at PND35 and PND105, including weight, naso-anal length, and abdominal circumference. Hepatic, renal, and adipose tissues were analyzed macro- and microscopically, along with biochemical analyses. Statistical analyses included ANOVA and generalized linear models. The hypothetical model confirmed that no significant variations occurred between generations, indicating that effects were driven by group, age, and sex differences. The analysis revealed that DDD/DDE synergism and female sex significantly influenced hepatic, renal, cerebral, and white adipose tissues. DDD/DDE exposure increased hepatic enzyme activity, reduced cerebral cholinesterase and renal antioxidants, and altered adipocyte mass. Age also influenced enzymatic activity and development, with notable differences between PND35 and PND105 in tissues and biometric indices. In conclusion, DDD/DDE exposure, particularly in females, significantly impacted hepatic, renal, cerebral, and adipose tissues. The results highlight that observed effects depend on group, age, and sex, emphasizing the risks associated with environmental contamination.

Effect of the simultaneous addition of cyanidin 3-glucoside and cyanidin 3-rutinoside in boar semen preserved under refrigeration at 17°C for 168 hours

Artificial insemination is widely used in swine reproductive management, allowing a single high-genetic-value male to fertilize a larger number of females. However, the dilution of spermatozoa in cooling media does not prevent oxidative processes that reduce the fertilizing capacity of sperm cells. This study investigated the effects of the antioxidant compounds cyanidin 3-glucoside and cyanidin 3-rutinoside, present in açaí extract, on sperm motility and the integrity of the plasma and acrosomal membranes of boar spermatozoa cooled to 17 ºC for up to 168 hours and the impact of these compounds on preventing the formation of superoxide anions. Semen samples were diluted with different concentrations of these compounds and compared with a long-term extender (Vitasem®) and a negative control. The results were evaluated at three time points: initial (time 0), after 96 hours, and after 168 hours of cooling. Vitasem® maintained high levels of motility and sperm plasma membrane integrity, while the cyanidins did not provide significant improvements compared to the negative control. Statistical analysis indicated that the addition of cyanidin 3-glucoside and cyanidin 3-rutinoside at the tested concentrations did not result in significant improvements in sperm characteristics. These findings suggest the need to explore other concentrations and combinations of antioxidants to optimize sperm preservation during cold storage.

The role of granulosa cells in oocyte development and aging: Mechanisms and therapeutic opportunities

Granulosa cells (GCs) are essential for oocyte maturation, providing metabolic support, hormonal signaling, and structural integrity critical to successful follicular development. However, advancing age disrupts these functions, driven by factors such as increased oxidative stress, mitochondrial dysfunction, and transcriptomic and proteomic alterations. These age-related changes in GCs contribute to compromised oocyte quality, diminished follicular support, and a decline in fertility, particularly in women of advanced maternal age. This review highlights recent progress in understanding the pivotal roles of GCs in maintaining oocyte health, with a focus on the mechanisms underlying their aging-related dysfunction. Furthermore, we explore promising therapeutic strategies, including antioxidant therapies, metabolic modulators, and GC-based rejuvenation techniques, aimed at mitigating the impacts of reproductive aging. By consolidating and analyzing existing research, this review provides valuable perspectives on fertility preservation and factors shaping reproductive outcomes in women of advanced maternal age.

Thermo-sensitive ε-polylysine-heparin-poloxamer hydrogel-encapsulated BMSCs promote endometrial regeneration

Endometrium plays a key role in embryo implantation and maintenance of pregnancy. However, to repair endometrial injury is still a challenge. In recent years, hydrogel materials have been widely used as effective support matrices to prevent intrauterine adhesions after endometrial injury. They can also be used as preparation scaffolds for encapsulating MSCs and certain therapeutic drugs. This study aimed to develop a preparation scaffold with high tissue affinity, high viscoelasticity and controlled release for repair of endometrial injury. The scaffold utilized heparin poloxamer (HP) as the matrix material and ε-polylysine (EPL) as the functional excipient to prepare a hydrogel that is suitable for endometrial adhesion and further encapsulate BMSCs. Furthermore, a strategy of the thermo-sensitive EPL-HP hydrogel-encapsulated BMSCs were used for better homing of BMSC after transplantation into the rat endometrial injury model, so as to exert the potential of endometrial regeneration by activating Nrf2 to regulate SDF-1/CXCR4 axis.

Exploring comprehensive toxic effects of fludioxonil on Caenorhabditis elegans

Fludioxonil is a phenylpyrrole fungicide widely used in agriculture. Despite its efficacy against target fungi, there have been concerns raised regarding the potential adverse effects on non-target organisms. This study assesses its toxicity effects on Caenorhabditis elegans (C. elegans) across physiological, cellular, neuronal, and behavioral dimensions. At the physiological level, fludioxonil significantly reduces the growth, lifespan, and reproductive capacity of C. elegans, indicating disruptive effects on overall organismal health. At the cellular level, fludioxonil elevates reactive oxygen species (ROS), which can result in oxidative stress. At the neuronal level, fludioxonil induces dopaminergic neurodegeneration and upregulates critical neurotransmission genes dat-1 and unc-47, which affects the nervous system. At the behavioral level, C. elegans exposed to fludioxonil exhibits increased locomotion and abnormal behaviors. These findings collectively demonstrate that fludioxonil exerts multifaceted toxic effects on non-target organisms, challenging the assumption of its safety and suggesting significant implications for ecosystem health and safety regulations.

The mitochondrial DNA copy number and ovary-related reproductive disorders: A bidirectional two-sample Mendelian randomization study

OBJECTIVE

In the present study, a bidirectional two-sample Mendelian randomization approach was utilized to explore potential causal relationships between mitochondrial DNA copy number (mtDNA-CN) and ovary-related reproductive disorders (ORRDs), including ovarian dysfunction, ovarian cyst, polycystic ovary syndrome (PCOS), premature ovarian failure (POF) and ovarian endometriosis.

METHODS

Genetic associations with mtDNA-CN were obtained from three genome-wide association study (GWAS) summary statistics from the UK Biobank, and ORRD data were investigated using summary statistics from the FinnGen cohort. Single nucleotide polymorphisms (SNPs) correlated with mtDNA-CN were selected as genetic instrumental variables (IVs) to estimate the causal effect of mtDNA-CN on ORRDs using the inverse-variance weighted (IVW) method with heterogeneity and pleiotropy analysis, and we repeated this in the opposite direction using instruments for ORRDs.

RESULTS

We found that the genetically predicted mtDNA was indicative of increased levels of PCOS (OR = 1.16; P < 0.001) and ovarian endometriosis (OR = 1.25; P = 0.007) in the IVW analysis and was not associated with the risk of other ORRDs. In the reverse direction, genetically predicted ORRDs were not associated with mtDNA-CN levels in the IVW analysis. Sensitivity and replication analyses showed the results to be stable.

CONCLUSION

We found that mtDNA-CN may increase the risk of PCOS and ovarian endometriosis. This may have implications for mtDNA-CN as a biomarker for these conditions in clinical practice.

The role of toll-like receptor 4 in the development of endometriosis and the benefits of trastuzumab in the treatment of endometriosis: a rat model

We aimed to investigate TLR-4 receptor activity in the development of endometriosis and the effect of trastuzumab in experimentally induced endometriotic tissue via TLR-4 in this study. Twenty-eight female Wistar-Albino rats were divided into four groups: Group 1 (Control Group), Group 2 (Endometriosis Group), Group 3 (Endometriosis + Trastuzumab Group), and Group 4 (Trastuzumab Group). All animal tissue samples were collected. Histopathological, immunohistochemical, and biochemical analyses were performed. In histopathological analysis, there was a significant difference between Group 2 and other groups in terms of connective tissue edema, inflammation, hemorrhage, epithelial damage, and mast cell density. In immunohistochemical analysis with TLR-4, Group 2 exhibited strong staining. In biochemical analysis, it was found that there was a highly significant difference between Group 2 and Group 1 considering the Malondialdehyde (MDA) levels in plasma samples. There was no significant difference in terms of the MDA levels among other groups. Considering the glutathione levels in the plasma samples, it was found that there was a highly significant difference between Group 2 and Groups 3 and 4. Trastuzumab may play a role in the treatment of histopathological damage and fibrosis in experimentally induced endometriotic implants by showing anti-inflammatory and antiproliferative activity.

Ferroptosis in Endometriosis: Traditional Chinese Medicine Interventions and Mechanistic Insights

Endometriosis (EMS) is a chronic, estrogen-dependent inflammatory disease affecting 5-10% of women of reproductive age, characterized by the growth of endometrial tissue on the outside of the uterus. The dysregulation of iron metabolism leads to the accumulation of iron ions at the lesion sites, resulting in oxidative stress and pro-inflammatory responses that promote the progression of EMS. The mechanisms underlying ferroptosis in EMS primarily involve iron accumulation, lipid peroxidation, and loss of glutathione peroxidase 4 activity. These mechanisms confer resistance to ferroptosis within the ectopic tissues and facilitate cell survival and proliferation. Traditional Chinese medicine (TCM) has demonstrated therapeutic potential for modulating ferroptosis. Studies have shown that TCM monomers may regulate ferroptosis by modulating iron transport proteins and anti-oxidant defense mechanisms. TCM formulas employ distinct treatment strategies depending on the stage of EMS: in the early stages, they promote ferroptosis to control lesion growth, whereas in the later stages, they inhibit ferroptosis to reduce oxidative stress and inflammation in order to improve reproductive health and slow disease progression. This study provides a new perspective on potential therapeutic strategies for the management of EMS by summarizing the role of ferroptosis in its pathological mechanisms and reviewing findings on the use of TCM in regulating ferroptosis.

Ramipril ameliorates endometriosis by inducing oxidative stress-mediated apoptosis in the wistar rat

Endometriosis is illustrated by the presence of ectopic endometrial cells capable of evading apoptosis outside the uterus. Apoptotic and anti-apoptotic factors in the extra uterine microenvironment can be compromised by the impairment in oxidative status. Angiotensin Converting Enzyme (ACE) Inhibitors and Nitric Oxide (NO) modulators play pivotal role in inflammation, angiogenesis, apoptosis and in abrogating oxidative imbalance. Therefore, in the current study we investigate the role of ACE inhibitor and or NO modulators in mitigating the proliferation of ectopic endometrial lesions in rat model. Sixty adult female virgin wistar rats were utilized; out of which fifteen were used as donor rats and rest forty-two were randomly divided into seven groups after surgical implantation of endometrial explants into rats (group II-VII). Histomorphometric assessment of uteri and ectopic lesions was performed by Hematoxylin and eosin (H-E) staining, followed by immunohistochemical study for Proliferating cell nuclear antigen (PCNA), Bax and Bcl-2. Oxidative stress parameters were evaluated by biochemical estimations, succeeded by immunoblotting of Poly [ADP-ribose] polymerase 1 (PARP1). Additionally, immunoblotting of Vascular endothelial growth factor (VEGF), Bax, Bcl-2 and caspase-3 was also performed. Significant decrease in the diameter of lesions with diffused staining at the extracellular spaces of stromal cells for PCNA accompanied by significant decrease in the expression of VEGF (p < 0.00001) was observed in group III. Furthermore, increased expression of Bax:Bcl-2 ratio (p < 0.001) and cleaved caspase-3 (p ≤ 0.0001) in ectopic lesions of group III was also observed. Administration of ramipril alone results in triggering oxidative stress mediated cleavage of PARP1, augmenting apoptosis in the ectopic lesions.

Overview of Nrf2 as a target in ovary and ovarian dysfunctions focusing on its antioxidant properties

Female infertility is a common issue caused by various factors, such as hormonal imbalances, age-related decline in oocyte quality, and lifestyle choices. Ovarian dysfunction is a prevalent cause, impacting fertility by damaging cells and impairing functions. Oxidative stress (OS) is a condition resulting from an imbalance between natural antioxidants and the generation of oxidants. This phenomenon acts as a double-edged sword, playing a crucial role as a signaling mechanism in both physiological and pathological processes related to the female reproductive system. OS is linked to ovarian dysfunction, leading to cell damage and reduced fertility. Nrf2 is a key regulator in oxidative homeostasis, helping to defend against OS and improve ovarian function in women of reproductive age. Therefore, this review aims to highlight the role of Nrf2 in the female reproductive system, focusing on its antioxidant properties.

Study of Ovarian Damage in Piglets in an Experimental Model of Neonatal Asphyxia

Background/Objectives: Perinatal asphyxia constitutes a major complication of the perinatal period with well-described effects on multiple organs and systems of the neonate; its impact, though, on the ovaries is hardly known. The objective of the present study was to investigate potential histological alterations of the ovaries in an animal model of perinatal asphyxia with or without resuscitation. Methods: This was a prospective, randomized animal study; 26 female Large White/Landrace piglets, aged 1-4 days, were the study subjects and were randomly allocated in 3 groups. In Group A (control), the animals had their ovaries surgically removed without any manipulation other than the basic preparation and mechanical ventilation. The other 2 groups, B (asphyxia) and C (asphyxia/resuscitation), underwent asphyxia until bradycardia and/or severe hypotension occurred. At the hemodynamic compromise, animals in group B had their ovaries surgically removed, while animals in group C were resuscitated. Following return of spontaneous circulation (ROSC), the latter were left for 30 min to stabilize and subsequently had their ovaries surgically removed. The ovarian tissues were assessed by the pathologists for the presence of apoptosis, balloon cells, vacuolated oocytes, and hyperplasia of the stroma. The histological parameters were graded from 0 (absence) to 3 (abundant presence). Results: The presence of balloon cells and apoptosis was found to be more prominent in the ovaries of animals in groups B and C, compared to that of the control group at a statistically significant degree (p = 0.0487 and p = 0.036, respectively). A significant differentiation in balloon cell presence was observed in cases with higher grading (2-3) in the asphyxia group (with or without resuscitation) (p value: 0.0214, OR: 9, 95% CI: 1.39-58.4). Although no statistically significant difference was noted regarding the other 2 histological parameters that were studied, there was a marked negative correlation between the duration of asphyxia and grade of vacuoles in oocytes when the potential effect of the duration of asphyxia or resuscitation on the histological findings was investigated (r = -0.54, p = 0.039). Conclusions: We aimed at investigating the potential effect on the neonatal ovaries in our animal model of perinatal asphyxia. Given that the presence of apoptosis and balloon cells was more prominent in cases of asphyxia, it can be speculated that perinatal asphyxia might have an impact on the neonatal ovaries in addition to the other, better-studied systemic effects. More research is needed in order to clarify the potential effect of perinatal asphyxia on the ovaries.

Supplementation with N-Acetyl-L-cysteine during in vitro maturation improves goat oocyte developmental competence by regulating oxidative stress

Oocyte quality can affect mammal fertilization rate, early embryonic development, pregnancy maintenance, and fetal development. Oxidative stress induced by reactive oxygen species (ROS) is one of the most important causes of poor oocyte maturation in vitro. To reduce the degree of cellular damage caused by ROS, supplementation with the antioxidant N-Acetyl-L-cysteine (NAC) serves as an effective pathway to alleviate glutathione (GSH) depletion during oxidative stress. This study investigated the effects of NAC supplementation during in vitro maturation of goat oocytes and explored the molecular mechanisms of maturation by transcriptome sequencing of MⅡ oocytes. The results showed that 1.5 mM NAC significantly increased the rates of oocyte maturation and cumulus cell expansion and improved the subsequent development of embryos. During the subsequent culture of parthenogenetically activated embryos, 1.5 mM NAC significantly increased the division rate of oocytes and blastocyst rate. It also reduced the accumulation of ROS, increased the level of GSH, alleviated oxidative stress, and enhanced the antioxidant capacity and cell metabolic activity. Transcriptome sequencing results revealed that NAC treatment significantly increased the expression of SIRT1, GGCT, and MITF genes related to the cellular antioxidant system, as well as the IDH3G gene related to energy metabolism, and decreased the expression of CASP8, FOS, and MMP1 genes related to apoptosis and cell invasion, as well as the CCL2. and CXCL8 genes related to the inflammatory response. In conclusion, the findings suggest that NAC supplementation significantly reduces oxidative stress, improves antioxidant capacity and metabolic activity, promotes oocyte maturation, and improves oocyte quality.

Effects of dietary quercetin on retrieved mouse oocytes and in vitro fertilization outcomes

OBJECTIVE

To investigate the effects of dietary quercetin on the retrieved mouse oocytes and IVF outcomes.

METHODS

Female mice were divided into two groups. Mice were given 0.2 mL water without (control group) or with quercetin 30 mg/kg (quercetin group) orally via gavage, once a day for 21 consecutive days. After that female mice were superovulated for in vitro fertilization. We observed the effect of dietary quercetin on the number of retrieved oocytes, oocyte degeneration rate, fertilization rate, blastocyst formation rate, and blastocyst cell numbers.

RESULTS

There was no difference in the number of retrieved oocytes per mouse (27.3±6.7 and 27.2±5.8), oocyte fragmentation rate (28.4% and 25.0%), fertilization rate (47.4% and 50.6%) and blastocyst formation rate (34.8% and 34.7%) in the quercetin group compared to the control group. The proportion of hatching and hatched blastocyst was significantly lower in the quercetin group (17.2% and 27.8%, p=0.004) and significantly lower numbers of cells in TE (47.4±15.3 and 57.2±17.7) and total cells (66.2±18.5 and 77.5±20.7) compared to the control group (p=0.001).

CONCLUSIONS

Dietary quercetin supplementation has a detrimental effect on mouse embryo quality. Moreover, it did not show any beneficial effect on the ovary in both quantity and quality. This finding raises awareness of the general use of dietary quercetin supplements in infertile females.

Ustiloxin A impairs oocyte quality by disrupting organelles function

Oocyte quality is pivotal for fertilization and early embryonic development. Ustiloxin A (UA), is an emerging mycotoxin that has been frequently detected in rice and paddy. Because UA has been reported to be phytotoxic and cytotoxic, it poses a potential hazard to human and animal health. However, the effects of UA on oocyte maturation remain unknown. Here, we investigated the effects of acute UA exposure on mouse oocyte maturation. First, UA exposure inhibited oocyte maturation in a concentration-dependent manner and induced meiotic arrest by disrupting spindle assembly and reducing actin density. Moreover, mitochondrial function was substantially disrupted in oocytes upon UA exposure. Aberrant mitochondrial distribution, substantial downregulation of mitochondrial dynamics-associated genes Mfn1, Mfn2 and Fis1, decreased membrane potential and TOM20 expression were observed in UA-exposed oocytes; these effects further led to oxidative stress and DNA damage. Furthermore, UA induced ER and Golgi dysfunction and triggered ER stress by increasing GRP78 expression, which ultimately resulted in autophagy and early apoptosis in oocytes. Therefore, these results demonstrate that UA impairs oocyte quality by disrupting organelles function, providing new insight into the influence of UA on female reproduction in mammals.

Association between Life's Essential 8 and Infertility as Well as the Mediating Effects of Oxidative Stress and Inflammatory Factors Among U.S. Women Aged 18-45 Years

Management of cardiovascular disease in pregnancy is important, yet the association between cardiovascular health and infertility is rarely reported. In this study, we aimed to explore the association between Life's Essential 8 (LE8), a novel cardiovascular health (CVH) measure, and infertility, and to investigate potential mediating mechanisms. This study investigated cross-sectional data from the 2013-2018 National Health and Nutrition Examination Survey. LE8 score (ranging from 0 to 100) was calculated as the unweighted average of eight CVH metrics. The association between LE8 and infertility was explored through weighted multiple logistic regression. Restricted cubic splines were used to explore nonlinear correlation. In addition, mediation analysis was conducted to investigate the role of oxidative stress and inflammatory markers systematically. After strict exclusion criteria, 1703 American women aged 18-45 years were included. After full adjustment, the LE8 score showed a negative correlation with infertility [per 1 SD increase, OR = 0.675, 95% CI: 0.553-0.824], with a linear dose-response relationship (non-linear P = 0.122). Similar linear negative correlations were found between health factor scores and infertility, with higher body mass index and glucose scores having a significantly lower risk of infertility. Stratified analyses showed a stronger inversed relationship between LE8 and infertility in younger populations. Moreover, mediation analysis revealed that uric acid concentration and lymphocyte count mediated the effect of LE8 on infertility (P < 0.05). LE8 and its subscale scores were linearly and negatively associated with infertility, which may be mediated in part through uric acid and lymphocyte count. Focusing on weight management and glycemic control can effectively reduce the risk of infertility.

Endometriosis: A new perspective on epigenetics and oxidative stress

As a complex chronic gynecological disorder characterized by multifaceted etiology involving genetics, environment, immunity and inflammation, endometriosis (EM) has long been a significant concern for women of reproductive age worldwide. This review aimed to comprehensively examine the interplay between epigenetics and oxidative stress (OS) in the pathogenesis of EM. Through the integration of cutting-edge research, the response of OS signals to epigenetic modifications was explored. The microbiome exerts an influence on this causal regulatory relationship, and these mechanisms collectively contribute to the pathophysiology of EM. Specifically, this article highlighted the roles of epigenetics and OS in EM and underscored the importance of the microbiome as a regulatory link. A discussion was also held on the future directions of biomarkers and precision medicine, including the application prospects of epigenetic and OS markers in the diagnosis and treatment decision-making of EM, and innovations in therapeutic strategies like targeting epigenetic modifications and antioxidant therapies. Moreover, this review emphasized the potential of multi-omics integrated analysis to deepen the understanding of the disease, guide future therapeutic strategies and promote personalized medicine.

Vitrification affects the post-implantation development of mouse embryos by inducing DNA damage and epigenetic modifications

Vitrification is widely used in assisted reproductive technology (ART) for female infertility, but the long-term effect on the embryo of vitrification has not been comprehensively studied. The study aimed to investigate the effect of vitrification on long-term development of mouse embryos. The warmed embryos which were frozen at 8-cell stage were cultured in vitro until the blastocyst stage and were transferred into recipients. Immunofluorescence staining was performed to evaluate the reactive oxygen species (ROS) level, mitochondrial function, cell apoptosis, DNA damage and histone epigenetic modification in blastocysts. Transmission electron microscopy (TEM) analysis was performed to exam the mitochondrial ultrastructure in blastocysts. The related gene expression and transcriptome profiles were investigated by RT-qPCR and RNA-seq, respectively. Blastocyst and implantation frequencies were not significantly affected by vitrification. However, vitrification significantly reduced blastocyst cell number and the live pup frequency. Vitrification induced ROS accumulation, DNA damage, and apoptosis in mouse blastocysts. The homologous recombination (NHEJ) is the major DNA repair pathway for vitrified embryos. Vitrification elevated H3K4me2/3, H4K12ac, and H4K16ac levels and reduced m6A modification in blastocysts. Moreover, vitrification significantly altered transcriptome profiles of mice placentas and brains at embryonic day 18.5 (E18.5). Thus, vitrification exhibited a long-term effect on mouse embryo viability by increasing ROS levels, DNA damage, altering the epigenetic modifications and transcriptome profiles.

Higher oxidative balance score is associated with a decreased risk of infertility: an analysis of NHANES 2013-2020

Background

Oxidative stress plays a crucial role in the female reproductive system. The oxidative balance score (OBS) is a new measure for assessing the balance between antioxidant and pro-oxidative factors in diet and lifestyle. However, limited studies have explored the relationship between OBS and infertility.

Methods

We performed a cross-sectional study including 2,664 women aged 20-45 years, based on data from the 2013-2020 National Health and Nutrition Examination Survey (NHANES). The OBS was derived from 16 dietary components and 4 lifestyle factors. We used multivariate logistic regression analysis to examine the association between OBS and infertility.

Results

The analysis revealed a significant negative association between higher OBS and infertility risk, with an odds ratio (OR) of 0.98 (95% CI, 0.95-1.00) after full adjustment. Compared to the first quartile of OBS, the second, third, and fourth quartiles showed ORs of 0.71 (95% CI, 0.45-1.11), 0.79 (95% CI, 0.51-1.22), and 0.57 (95% CI, 0.35-0.92), respectively. Similarly, women in the highest dietary OBS and lifestyle OBS quartiles had a lower infertility risk compared to those in the lowest quartiles, with ORs of 0.60 (95% CI, 0.39-0.94) and 0.54 (95% CI, 0.32-0.93), respectively. Furthermore, subgroup analysis indicated that the association between the fourth quartile of OBS and infertility remained consistent, except among women with other ethnicities-including multi-racial, and college graduate or higher.

Conclusion

These findings suggest that high dietary OBS and lifestyle OBS are associated with a lower risk of infertility.

Impact of arsenic on male and female reproductive function: a review of the pathophysiology and potential therapeutic strategies

Arsenic is a ubiquitous metalloid and heavy metal that contributes to the global decline in human fertility. Humans are constantly exposed to arsenic through biotic and abiotic sources, especially ingestion of arsenic-contaminated food and water. Its exposure is associated with several adverse health challenges, including reproductive toxicity. In spite of its reported adverse effects, arsenic exposure remains a global challenge. Hence, this study provides a comprehensive review of the literature on the impact and mechanism of arsenic on male and female reproductive function. Additionally, a review of the potential therapeutic strategies is presented. Evidence from the literature reveals that arsenic upregulates reactive oxygen species (ROS) generation which mediates arsenic-induced suppression of the hypothalamic-pituitary-gonadal axis and inactivation of 3β-HSD and 17β-HSD activities, leading to reduced gonadal steroidogenesis. Through several oxidative stress-dependent signaling, arsenic induces the apoptosis of the germ cells, thus contributing to the development of infertility. At the moment, there is no specific treatment for arsenic-induced reproductive toxicity. However, increasing data form the scientific literature reveals the benefits of antioxidants in ameliorating arsenic-induced reproductive toxicity. These molecules suppress ROS generation and maintain optimal activities of the hypothalamic-pituitary-gonadal axis, leading to optimal steroidogenesis and gametogenesis as well as improved germ cells. Overall, this study revealed the impact and associated mechanism of arsenic-induced reproductive toxicity. It also provides evidence from the literature demonstrating potential therapeutic measures in managing arsenic-induced reproductive toxicity.

Antioxidant therapy for infertile couples: a comprehensive review of the current status and consideration of future prospects

Oxidative stress (OS) is established as a key factor in the etiology of both male and female infertility, arising from an imbalance between reactive oxygen species (ROS) production and the endogenous antioxidant (AOX) defenses. In men, OS adversely affects sperm function by inducing DNA damage, reducing motility, significantly impairing sperm vitality through plasma membrane peroxidation and loss of membrane integrity, and ultimately compromising overall sperm quality. In women, OS is implicated in various reproductive disorders, including polycystic ovary syndrome, endometriosis, and premature ovarian failure, leading to diminished oocyte quality, disrupted folliculogenesis, and poorer reproductive outcomes. Antioxidant therapy represents a promising intervention to mitigate the harmful effects of ROS on reproductive health in additions to its easy accessibility, safety, and low cost. Despite several findings suggesting improvements in fertility potential with AOX therapy, the data remains inconclusive regarding optimal dosage and combination, duration of treatment, and the specific patient populations most likely to benefit. In this review, we discuss the role of AOXs in the management of infertile couples, focusing on their biological mechanisms, potential adverse effects, therapeutic efficacy, and clinical applications in improving reproductive outcomes in both natural conception and medically assisted reproduction. Additionally, we highlight the current practice patterns and recommendations for AOX supplementation during the course of infertility treatment. Further, we provide an overview on the limitations of the current research on the topic and insights for future studies to establish standardized AOX regimens and to assess their long-term impact on key outcomes such as live birth rates and miscarriage rates.

Formononetin promotes porcine oocytes maturation and improves embryonic development by reducing oxidative stress

Increasing evidence has demonstrated that oxidative stress impairs oocyte maturation and embryonic development. Conventionally, antioxidants have been applied in vitro systems to improve oocyte maturation and blastocyst rates. Formononetin (FMN) is a flavonoid that has been shown to have various pharmacological effects, including antioxidants. In this study, we delved into the impact of FMN, acting as an antioxidant, on the in vitro development of oocytes and blastocysts within the culture system. FMN supplementation at 0.5 μM enhanced the rate of first polar body extrusion and blastocyst formation post parthenogenetic activation. It also increased mitochondrial function and ATP levels, reduced intracellular reactive oxygen species, and elevated intracellular GSH levels in both oocytes and embryos. Moreover, FMN significantly decreased autophagy and apoptosis levels in blastocyst cells, potentially via regulation of the Nrf2/Keap1 pathway. This is the first study to report that FMN supplementation benefits the in vitro culture of oocytes and early embryo development, potentially by regulating oxidative stress, mitochondrial function, and autophagy.

The possible pathogenic mechanisms of microorganisms in infertility: a narrative review

Infertility can harm a patient in physical, psychological, spiritual, and medical ways. This illness is unusual because it affects the patient's companion and the patient individually. Infertility is a multifactorial disease, and various etiological factors like infection are known to develop this disorder. Recently published studies reported that different bacteria, such as Chlamydia trachomatis, Mycoplasma spp., Ureaplasma urealyticum, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa, can lead to infertility by immunopathological effects, oxidative stress, and adverse effects on sperm concentration, motility, morphology, and DNA condensation. Among viruses, Human papillomavirus and Herpes simplex virus reduce sperm progressive motility and sperm concentration. The viruses can lead to the atrophy of the germinal epithelium and degenerative changes in the testes. Candida albicans also harm sperm quality, motility, and chromatin integrity and induce apoptosis in sperm cells. Finally, Trichomonas vaginalis leads to distorted heads, broken necks, and acrosomes exocytosis in sperms. This parasite decreases sperm viability and functional integrity. Noteworthy, oxidative stress could have a role in many pathological changes in the reproductive system. Recent findings show that microorganisms can increase reactive oxygen species concentration inside the host cells, leading to oxidative stress and sperm distress and dysfunction. Therefore, this article explores the potential significance of critical bacteria linked to infertility and their pathogenic mechanisms that can affect sperm function and the female reproductive system.

Oxidative Stress and the NLRP3 Inflammasome: Focus on Female Fertility and Reproductive Health

Chronic inflammation is increasingly recognized as a critical factor in female reproductive health; influencing natural conception and the outcomes of assisted reproductive technologies such as in vitro fertilization (IVF). An essential component of innate immunity, the NLR family pyrin domain-containing 3 (NLRP3) inflammasome is one of the major mediators of inflammatory responses, and its activation is closely linked to oxidative stress. This interaction contributes to a decline in oocyte quality, reduced fertilization potential, and impaired embryo development. In the ovarian milieu, oxidative stress and NLRP3 inflammasome activation interact intricately, and their combined effects on oocyte competence and reproductive outcomes are significant. The aims of this review are to examine these molecular mechanisms and to explore therapeutic strategies targeting oxidative stress and NLRP3 inflammasome activity, with the goal of enhancing female fertility and improving clinical outcomes in reproductive health.

Protective effect of adiponectin on oxidative stress-induced ovarian granulosa cell senescence in geese

Geese are susceptible to oxidative stress during breeding, leading to senescence of granulosa cells (GCs) and reduced egg production. Adiponectin (ADPN) is a cytokine secreted by adipose tissue that functions to regulate metabolism and antioxidants. However, its role in the regulation of goose GCs is unclear. To investigate this, senescence in primary goose GCs was induced by D-gal and assessed via RT‒qPCR, senescence-associated β-galactosidase (SA-β-gal) staining, immunofluorescence, flow cytometry, and transcriptomics. The effect of ADPN on GC senescence was investigated by overexpressing and knocking down ADPN expression. The results showed that ADPN could alleviate oxidative stress and cell cycle arrest in GCs, reduce the expression of the senescence-associated secretory phenotype (SASP)-related genes IL-6 and IL-8, regulate the metabolic capacity of GCs, reduce the accumulation of SA-β-gal, maintain telomere length, and alleviate the senescence of GCs induced by D-gal. The RNA-seq results provided further evidence for the regulatory effect of ADPN on GC senescence. ADPN was shown to attenuate oxidative stress-induced GC senescence through the AGE (Advanced glycation end products)-RAGE (Receptor of advanced glycation end products) and NOD-like receptor pathways. These findings may contribute to the development of improved theoretical references for improving egg-laying performance and prolonging the service life of geese.

Heat stress induces oxidative stress and activates the KEAP1-NFE2L2-ARE pathway in reproduction-related cells

Heat stress negatively affects the reproductive function of in animals and humans. Although a relationship between heat and oxidative stress has been suggested, the underlying mechanism has not been sufficiently examined in reproduction-related cells. Therefore, we aimed to investigate whether heat stress induces oxidative stress using a variety of reproduction-related cells including bovine placental and cumulus-granulosa cells, human cell lines derived from cervical and endometrial cancers, and fibroblasts derived from endometrium. Quantitative polymerase chain reaction analysis showed that the expression levels of representative heat and oxidative stress-related genes were significantly increased in cells cultured at high temperatures compared with those in cells cultured at basal temperatures. Moreover, luciferase reporter assays showed that the reporter activity of the heat shock element and antioxidant responsive element (ARE) was increased in cells cultured at high temperatures compared with that in cells cultured at basal temperatures. Furthermore, the stability of nuclear factor erythroid 2 like 2 (NFE2L2), a master regulator of the cellular stress response, increased under high temperatures. Point mutations in Kelch-like ECH-associated protein 1 (KEAP1) cysteine residues reduced the luciferase activity. Our results suggest that heat stress induces oxidative stress and that the KEAP1-NFE2L2-ARE pathway may play a protective role in reproduction-related cells against heat stress.

Polycystic Ovary Syndrome and Oxidative Stress. Natural Treatments

Polycystic ovary syndrome (PCOS) is one of the most frequent endocrinopathology affecting women in their reproductive ages. However, PCOS is also related to metabolic abnormalities such as metabolic syndrome (MS), insulin resistance (IR), and type 2 diabetes, among others. Consequently, an inflammatory and pro-oxidative status is also present in these patients, aggravating the syndrome's symptoms. This work aims to discuss some late treatments that focus on oxidative stress (OS) as a central feature related to primary PCOS abnormalities. Therefore, this review focuses on the evidence of anti-oxidant diets, natural compounds, mineralocorticoids, and combined therapies for PCOS management. Oxidative stress (OS) is important in PCOS pathogenesis. In this regard, increased levels of oxidative oxygen species and decreased levels of anti-oxidant agents’ impact PCOS's reproductive and metabolic features. In the last years, non-pharmacological therapies have been considered a first line of treatment. For these reasons, several natural compounds such as Kelult honey (KH), Foeniculum Vulgare, Calendula officinalis Linn, Eugenia caryophyllus and Myristicafragrans, vitamin C, vitamin E, selenium, zinc, beta-carotene, magnesium, curcumin, mineralocorticoids and melatonin alone or in combination are powerful anti-oxidant agents being used for PCOS management. Data presented here suggest that natural therapies are essential in managing both reproductive and metabolic features in PCOS patients. Due to the results obtained, these incipient therapies deserve further investigation.

The Role of Quercetin for the Treatment of Endometriosis and Endometrial Cancer: A Comprehensive Review

Endometrial glands and stroma can be seen outside the uterine cavity in endometriosis, a gynecological disorder linked to estrogen dependency. Hormonal therapies, surgical excision, and non-steroidal anti-inflammatory drug therapy are among the traditional endometriosis treatments, however, various side effects limit their efficacy. Therefore, it is vital to research complementary and alternative therapeutic modalities to decrease the side effects of conventional therapies. While the search for the best endometriosis treatment continues, the focus is being paid to the assistance provided by polyphenols, notably quercetin. A broad spectrum of health-improving benefits of quercetin includes interactions with endometriosis-related molecular targets such as cell proliferation, apoptosis, invasiveness, inflammation, and oxidative stress. According to already-known research, medicines that mimic the physiological effects of quercetin are good candidates for creating novel endometriosis therapies. This review aims to comprehensively review quercetin's potential as a non-pharmacological treatment for endometriosis by interacting with several cellular and molecular targets.

Associations of maternal urinary nitrophenol concentrations with adverse birth outcomes and neurodevelopment delay at 4 years of age: The Japan environment and children's study

Maternal urinary nitrophenol concentrations are reportedly associated with preterm birth and foetal/offspring development delay, but the evidence is still inconclusive. We investigated the association between maternal urinary concentrations of 4-nitrophenol (4NP) and 3-methyl-4-nitrophenol (3M4NP) and adverse birth outcomes, as well as offspring neurodevelopment delay, defined using the Ages and Stages Questionnaires at 4 years of age, stratified by offspring sex. A total of 3650 non-hypertensive mothers with singleton births were enrolled from the Japan Environment and Children's Study. High 4NP (≥0.41 μg/L) and 3M4NP (≥0.29 μg/L) were defined as ≥ lowest concentration minimum reporting level. Four groups were created using these dichotomized 4NP and 3M4NP concentrations: 'both low', 'either high/low', and 'both high'. Multivariable logistic regression models were used to estimate the adjusted odds ratios (aOR) and population attributable fraction (PAF). For 4NP and 3M4NP, 68.4% and 19.0% of participants had 'high' urinary concentrations, respectively. Compared to 'both low', the overall analysis showed no significant associations between 'both high' and any of the outcomes. However, the stratified analysis showed that the aOR (95% confidence interval [CI]) and PAF (95% CI) for 'both high' regarding preterm birth (<37 weeks' gestation) were 2.7 (1.3, 5.7) and 16.3% (2.5%, 28.1%), respectively, in male offspring. Among female offspring, the aOR and PAF for the 'both high' regarding small-for-gestational-age (SGA)-defined as weight-for-gestational age <10 percentile based on the Japanese neonatal anthropometric charts-were 1.7 (1.0, 2.8) and 10.6% (-0.2%, 20.2%), respectively. Urinary 4NP and 3M4NP concentrations showed no association with low birth weight (<2500 g) and neurodevelopment delay. In conclusion, offspring sex-specific associations of maternal urinary nitrophenols with preterm birth and SGA were observed. Even slight elevations in their levels may explain a certain proportion of preterm birth and SGA. The exposure source, expressed by urinary nitrophenols, should be identified.

Exploring potential pathways from oxidative stress to ovarian aging

AIM

In developed nations, women have increasingly deferred childbearing, leading to a rise in demand for infertility treatments and the widespread use of assisted reproductive technologies. However, despite advancements in in vitro fertilization (IVF), live birth rates among women over 40 remain suboptimal. Mitochondrial dysfunction is widely recognized as a key factor in the processes driving the age-related deterioration in both the quantity and quality of oocytes. We aim to summarize current insights into ovarian aging, with a particular focus on pathways that impair mitochondrial function, and explore directions for future research.

METHODS

Electronic databases were searched for articles published up to June 30, 2024.

RESULTS

Ongoing ovulation, luteolysis, and menstruation trigger exogenous reactive oxygen species (ROS)-mediated oxidative stress that damages mitochondrial DNA. This, in turn, reduces nuclear gene expression, compromises mitochondrial oxidative phosphorylation, and diminishes adenosine 5' triphosphate production. Persistent endogenous ROS further exacerbate mitochondrial DNA damage and aneuploidy, ultimately causing irreversible chromosomal abnormalities, leading to oocyte aging.

CONCLUSIONS

We have delineated the pathway from oxidative stress to ovarian aging. Early detection and management of ovarian aging present challenges and opportunities to enhance IVF treatment strategies.

Nitrate-Nitrite-Nitric Oxide Pathway, Oxidative Stress, and Fertility Outcomes in Morbidly Obese Women Following Bariatric Surgery: A Systematic Review

Obesity reduces nitric oxide (NO) production due to endothelial nitric oxide synthase (eNOS) dysfunction, resulting in oxidative stress, mitochondrial dysfunction, and chronic inflammation. These factors have a negative impact on reproductive health, including oocyte quality, endometrial receptivity, and embryo implantation. When oxidative stress affects eNOS function, the nitrate-nitrite-nitric oxide (NO3-NO2-NO) pathway provides an alternate route for NO production. Bariatric surgery has been found to restore NO production, reduce oxidative stress, and improve fertility in morbidly obese women. This review investigates the molecular mechanisms by which bariatric surgery affects eNOS activity, the NO3-NO2-NO pathway, and oxidative stress reduction, with an emphasis on intracellular activities including mitochondrial biogenesis and NO production. A systematic review employing PRISMA criteria included articles published between 2000 and 2024 from PubMed, Scopus, and Embase that investigated NO3-NO2 pathways, oxidative stress markers, hormonal alterations, and reproductive outcomes in morbidly obese women following bariatric surgery. After evaluating 1542 studies, 11 were selected for the final analysis. Results showed a 45% increase in NO3-NO2 levels (p < 0.001), a 35% reduction in oxidative stress indicators (p < 0.01), a 60% increase in pregnancy rates, and a 50% increase in spontaneous ovulation rates following surgery. These benefits were connected to improved mitochondrial function and endometrial receptivity as a result of reduced oxidative stress and inflammation. The NO3-NO2-NO route is critical in compensating for lower NO generation under oxidative stress and hypoxia, and bariatric surgery significantly improves this pathway to optimize blood flow, mitochondrial function, and reproductive results.

Reproductive Health in Women with Major β-Thalassemia: Evaluating Ovarian Reserve and Endocrine Complications

Thalassemia is an autosomal recessive hereditary chronic hemolytic anemia characterized by a partial or complete deficiency in the synthesis of alpha- or beta-globin chains, which are essential components of adult hemoglobin. Mutations in the globin genes lead to the production of unstable globin chains that precipitate within cells, causing hemolysis. This shortens the lifespan of mature red blood cells (RBCs) and results in the premature destruction of RBC precursors in the bone marrow. Regular red blood cell transfusions are the standard treatment for thalassemia. However, these transfusions can lead to increased iron overload, which can impair vital systems such as the liver, heart, ovaries, and endocrine system. Focusing on female reproductive endocrinology, recurrent blood transfusions can cause iron accumulation in the pituitary and hypothalamus, leading to hypogonadotropic hypogonadism (HH), the most common endocrinopathy in these patients, affecting 40-91% of women. Recurrent transfusions and the resulting iron overload can also lead to oxidative stress and ovarian damage in patients with beta-thalassemia major (BTM). Despite advancements in iron chelation therapy, hypothalamic-pituitary damage associated with HH contributes to subfertility and sexual dysfunction, often with little to no recovery. In women exposed to gonadotoxic drugs, particularly those with BTM, anti-Mullerian hormone (AMH)-a marker of ovarian reserve-is frequently used to assess ovarian damage. This review aims to explore the pathophysiology of β-thalassemia and its major clinical manifestations, with a focus on endocrine complications and their impact on ovarian reserve. It also investigates how metabolomics can provide insights into the disease's metabolic alterations and inform current and emerging therapeutic strategies to mitigate complications and optimize patient outcomes, potentially leading to more effective and personalized treatments.

Myo-inositol improves developmental competence and reduces oxidative stress in porcine parthenogenetic embryos

Objective

Myo-inositol (Myo-Ins), the most abundant form of inositol, is an antioxidant and plays a crucial role in the development and reproduction of mammals and humans. However, information elucidating the role of Myo-Ins in porcine embryonic development after parthenogenetic activation (PA) is still lacking. Therefore, we investigated the effect of Myo-Ins on porcine embryos and its underlying mechanisms.

Methods

In this study, various concentrations of Myo-Ins (0, 5, 10, and 20 mM) were added to the porcine zygotic medium (PZM3) during the in vitro culture (IVC) of porcine embryos. Several characteristics were evaluated, including cleavage rate, blastocyst formation rate, intracellular glutathione (GSH) and reactive oxygen species (ROS) levels in 4-5 cell stage embryos, total cell number, apoptotic rate in blastocysts, mitochondrial membrane potential (MMP), mitochondrial quantity, mitochondrial stress in the blastocysts, and gene expression for antioxidant and mitochondrial function markers. Additionally, the immunofluorescence of HO-1 was assessed.

Results

The results showed that Myo-Ins at concentrations of 10 and 20 mM significantly increased the blastocyst formation rate compared to the control group. Embryos supplemented with 20 mM Myo-Ins exhibited higher GSH levels and lower ROS levels than those in the control group. Myo-Ins supplementation also decreased the rate of apoptosis and the apoptotic index in the treatment groups. Additionally, embryos supplemented with 20 mM Myo-Ins showed increased mitochondrial membrane potential (MMP), greater mitochondrial quantity, and reduced oxidative stress in the mitochondria. Interestingly, the expression levels of genes related to mitochondrial function and the nuclear erythroid factor 2-related factor (NRF2) pathway were elevated in the Myo-Ins treated groups. Furthermore, immunofluorescence results indicated that 20 mM Myo-Ins significantly increased HO-1 expression in blastocysts compared to the control group.

Conclusion

In conclusion, 20 mM Myo-Ins supplementation enhanced blastocyst development and improved mitochondrial function by regulating apoptosis, reducing oxidative stress, and activating the NRF2 pathway.

Association between serum copeptin levels and non-obese normoglycemic polycystic ovary syndrome: A case control study

Objective

Copeptin is a glycopeptide that increases under stress and is present in polycystic ovary syndrome (PCOS) patients with metabolic system disorders. We examined the relationship between copeptin and reproductive function in patients with normoglycemic PCOS with anovulatory cycles and normal weight.

Materials and Methods

Women with unexplained infertility (n=52) and women with PCOS (n=57) were included in the study. PCOS was determined using the Rotterdam criteria. Biochemical tests including estradiol, follicle-stimulating hormone, luteinizing hormone, anti-Müllerian hormone (AMH), insulin, and copeptin were performed. Serum copeptin concentrations were measured using enzyme immunoassay.

Results

There were no significant differences in demographic data, insulin levels, and insulin resistance between the PCOS and healthy volunteers. Copeptin levels were lower in the PCOS group (p<0.001). A significant negative correlation was observed between AMH and copeptin in the control group (r=-0.402, p= 0.013). In the PCOS group, a negative correlation was observed between antral follicle count and copeptin, as well as between AMH and copeptin (r=-0.544, p<0.01). Receiver operating characteristic (ROC) curve analysis was performed to determine the predictive value of copeptin levels. The estimated areas under the ROC curves for serum concentration were found to be statistically significant (p<0.001) with a cut-off value of 2.78 (95% confidence interval 0.701-0.896), sensitivity of 0.87, and specificity of 0.70.

Conclusion

This study showed that copeptin levels are lower in patients with PCOS in the absence of insulin resistance and obesity than in healthy volunteers, and there is a negative correlation between copeptin and reproductive markers.

Effects of pretreatment strategies on fertility outcomes in patients with adenomyosis

Adenomyosis is a commonly encountered pathology in women of reproductive age and frequently coexists with infertility. The effect of adenomyosis on fertility, particularly on in vitro fertilisation and intracytoplasmic sperm injection outcomes, is not well understood. Various pretreatment modalities have been used to improve pregnancy rates and live birth outcomes; however, because of a lack of high-quality evidence, there is no clear consensus on the best pretreatment option. This review was conducted through a PubMed search aiming to highlight the relationship between pretreatment and fertility in women with adenomyosis. Medical, ablative surgical, and non-surgical therapies were reviewed. According to the current literature, gonadotropin-releasing hormone agonist therapy and placement of a levonorgestrel intrauterine system are two suitable medical pretreatment strategies that can improve the clinical pregnancy rates of patients with adenomyosis. Surgical ablation of adenomyosis can also be beneficial, although surgical management can be challenging. Non-surgical thermal techniques, including high-intensity focused ultrasound ablation, percutaneous microwave ablation, and radiofrequency ablation, are much less invasive techniques that have shown effectiveness in improving fertility. Although evidence remains limited, all these procedures have demonstrated a favourable safety profile. Further studies are needed to better develop these techniques and demonstrate their effectiveness.

Environmental exposure to lead and cadmium only minimally affects the redox system of the follicular fluid and the outcome of intracytoplasmic sperm injection

The purpose of our study was to determine the influence of lead and cadmium in concentrations commonly found in the environment on the redox system of the follicular fluid (FF) and on the results of assisted reproduction. A prospective study of 113 patients with unexplained infertility who qualified for intracytoplasmic sperm injection (ICSI). Patients with moderate or severe endometriosis or poor ovarian reserve were excluded from the study. Biochemical analyses and heavy metal assays of follicular fluid and serum (blood) were followed by statistical analyses of dependencies between lead and cadmium and the components of redox system and results of assisted reproduction. A highly significant linear correlation of lead (Pb) and cadmium (Cd) concentrations in serum and in FF was stated. The number of retrieved oocytes and MII (metaphase II stage) oocytes depended on the malondialdehyde (MDA), catalase (CAT), catalase/g of protein (CAT/g of protein), and glutathione reductase (GR) concentrations. Among biochemical factors, MDA was the only factor that correlated negatively with cadmium concentration in serum and FF and simultaneously influenced the number of retrieved oocytes and MII oocytes. The fertilization rate of MII oocytes was influenced by thiol groups-SH, SH/g of protein, CAT, CAT/g of protein, and glutathione peroxidase/g of protein (GPx/g of protein). The Pb and Cd concentrations in FF did not significantly influence the fertilization rates. Lead as well as cadmium at concentrations commonly found in women of reproductive age despite some adaptive changes in the redox system in follicular fluid do not cause large changes in the ovarian follicular environment as a whole and do not significantly worsen the final results of assisted reproduction.

Genetic evidence linking retinol to birth weight: A two-sample Mendelian randomization study

This study aims to clarify the potential causal effects of dietary antioxidant vitamins on pregnancy outcomes (miscarriage, preterm labor, and birth weight) using Mendelian randomization (MR). Our instrumental variables (IVs) were single-nucleotide polymorphisms (SNPs) linked to retinol, vitamin C, carotene, and vitamin E (P < 5×10-6). The summary statistics for miscarriage, preterm labor, and birth weight were extracted from genome-wide association studies (GWASs), with a sample size of 56,172, 5480, and 261,932, respectively. The present MR study primarily used the inverse-variance weighted method, with additional sensitivity analyses conducted to evaluate the robustness of the findings. We found that retinol was closely related to the birth weight (β=0.091, 95 %CI: 0.009-0.172, P=0.028), and sensitivity analyses showed similar results (MR-RAPS: OR=1.101, 95 %CI: 1.027-1.180; maximum likelihood: OR=1.098, 95 %CI: 1.011-1.194). While the relationship of retinol with miscarriage or preterm labor was not statistically significant. Additionally, our study did not reveal an association between the carotene, vitamin E, and vitamin C and pregnancy-related outcomes, miscarriage, preterm labor, and birth weight (all P > 0.05). In conclusion, our findings indicated a causal effect between retinol and birth weight and suggested that maintaining retinol at normal levels during pregnancy can prevent low birth weight. Therefore, it would be beneficial to measure retinol levels in pregnant women and to supplement with vitamin A in cases of deficiency, as these could be valuable strategies for improving pregnancy outcomes.

Melatonin ameliorates the toxic effects of 2,6-Dichloro-1,4-benzoquinone on mouse oocytes by restoring subcellular structures

2,6-Dichloro-1,4-benzoquinone (2,6-DCBQ) is a disinfection by-product (DBP) formed during the disinfection of drinking water. Due to its frequent detection and high concentrations, it has garnered significant attention. However, the effects of 2,6-DCBQ on oocyte meiosis remain poorly understood. In this study, we demonstrate that 2,6-DCBQ exposure disrupts nuclear maturation in oocytes by damaging the spindle and chromosome structure. Additionally, exposure to 2,6-DCBQ impairs cytoplasmic maturation by altering actin dynamics, disrupting cortical granule distribution, and compromising the function of key organelles, including the mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes. Supplementing melatonin during meiotic maturation reverses these effects, enhancing organelle function, reducing reactive oxygen species (ROS) levels, alleviating DNA damage, and inhibiting apoptosis. Together, these findings show that 2,6-DCBQ causes organelle dysfunction and meiotic disruption in oocytes, while melatonin provides protective effects against these disruptions during meiotic maturation.

The relationship between psychological stress and ovulatory disorders and its molecular mechanisms: a narrative review

This narrative review explores the relationship between psychological stress and ovulatory disorders, focusing on the molecular mechanisms involved. Ovulation is regulated by the hypothalamus-pituitary-ovarian (HPO) axis, and disruptions in this axis can lead to ovulatory dysfunction. Chronic psychological stress affects the HPO axis, resulting in abnormalities in hypothalamus hormone secretion, pituitary hormone release, and ovarian function. These disruptions cause ovulation disorders and menstrual irregularities. The mechanisms by which psychological stress affects ovulation involve alterations in neuropeptides and hormones, activation of the hypothalamic-pituitary-adrenal (HPA) axis, impairment of follicular development, generation of oxidative stress, and the decline in ovarian reserve function. Understanding these mechanisms is crucial for developing interventions to restore reproductive health. Psychological interventions, such as cognitive-behavioral therapy, have shown promise in improving ovulation and pregnancy rates in women with ovulatory disorders. Further research is needed to explore the specific mechanisms of these interventions and optimize treatment strategies. Addressing psychological factors is essential in managing reproductive health and ovulatory disorders.

Evidence based management of patients with endometriosis undergoing assisted conception: British fertility society policy and practice recommendations

Endometriosis is a chronic inflammatory condition in women of reproductive age, which can lead to infertility and pelvic pain. Endometriosis associated infertility is multifactorial in nature adversely affecting each step of the natural reproductive physiology and thereby processes and outcomes of Assisted Reproductive Technology (ART) cycles. These outcomes are further complicated by the subtype of endometriosis, being peritoneal, deep infiltrating and ovarian, which bear negative effects on ovarian reserve, response to stimulation, accessibility for oocyte retrieval, intraoperative safety and endometrial receptivity. There is still a lack of clear guidance about the role of surgery for ovarian endometriosis/endometriomas. This guideline evaluates the evidence of the impact of pelvic endometriosis and endometriomas on the outcome of ART and provides recommendations for management options before and during ART including intra-uterine insemination. Recommendations are made based on the current evidence for the management of patients with endometriosis across each step of ART with the primary aim of improving ART outcomes.

The ameliorative effect of chrysin on ovarian toxicity caused by methidathion in female rats

Introduction: Methidathion (MD) is commonly used in agriculture and has adverse effects on reproduction. Chrysin (CHR) has several advantageous properties, such as anti-inflammatory, anti-cancer, and antioxidant properties. The purpose of the current investigation was to assess CHR's therapeutic efficacy in reducing ovarian toxicity brought on by MD. Methods: Twenty-four female rats were divided into four groups of six animals each. Group 1 served as a control, while group 2 rats received MD (5 mg/kg). Rats in Group 3 received CHR at a dose of 50 mg/kg. Rats in group 4 received treatment with CHR after MD intoxication. Results and Discussion: Our research revealed that MD significantly (p < 0.001) increased the levels of MDA, caspase-3, FSH, LH, CA-125, and TNF-α but significantly (p < 0.001) decreased the levels of SOD, GSH, E2, and progesterone when compared to the control and CHR groups. After receiving CHR therapy, damage induced by MD was significantly (p < 0.001) repaired. Conclusion: This study showed that CHR could mitigate the adverse effects that MD causes to the ovaries by decreasing oxidative stress, inflammation, and apoptosis; improving antioxidant status; and restoring the correct ratio of sex hormones.

A reflexion on the oxidative stress and animal welfare: a review

A wide range of studies have documented the role of oxidative stress in the development of chronic pathological disorders and even in the aging itself. However, its significance to modern animal health and welfare remains neglected. Oxidative stress in biological systems refers to a disturbance in the balance between pro-oxidants and antioxidants in favour of the former, leading to potential damage of biomolecules. In farm animals, oxidative stress may be involved in several pathological conditions, including those that are relevant for animal production and the general welfare of the individuals, resulting in some cases in irreversible losses. The oxidative stress concept and how it may result in disease or be prevented are complex questions with no simple answers and therefore, call professionals for deep reflection, to maintain a high standard of animal welfare and production. The aim of this review was to gather relevant information on the characteristics of pro-oxidants and antioxidant as well as their significance in animal production systems.

Effects of dietary genistin supplementation on reproductive performance, immunity and antioxidative capacity in gestating sows

Genistin is an isoflavone of soybean, with estrogenic activity. This experiment was conducted to investigate its effect on reproductive performance, antioxidant capacity, and immunity in gestating sows. Seventy-two sows (Landrace × Yorkshire) were selected and randomly divided into two treatment groups (n = 36) based on their backfat thickness, parity and fed with basal diet or supplementation of 150 mg/ kg genistin to the basal diet based on DMI for the entire gestation period. Results showed that dietary genistin supplementation significantly increased the average number of live born per litter (p < 0.05), and tended to increase the number of healthy piglets per litter (p = 0.058), but decreased the average weight of live born per litter (p < 0.05). Dietary genistin supplementation significantly decreased the number of mummified and stillbirths per litter (p < 0.05). Moreover, the average daily feed intake (ADFI) and total feed intake of the gestating sows were also increased in the genistin-supplemented group (p < 0.05). Genistin significantly increased the serum concentrations of catalase (CAT), immunoglobulin A (IgA), IgG, and IgM at 35 days of gestation (p < 0.05). The serum concentrations of interleukin-10 (IL-10) and interferon-γ (IFN-γ) were also increased upon genistin supplementation (p < 0.05). However, genistin supplementation tended to decrease the serum concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and leptin at 85 days of gestation (p = 0.081 and p = 0.096, respectively). Interestingly, genistin supplementation decreased the transcript abundance of interferon-γ (IFN-γ) and placental imprinting gene H19, but significantly increased the transcript abundance of insulin-like growth factor I (IGF-I) and amino acid transporters such as the sodium-coupled neutral amino acid transporter 2 (SNTA2) and SNAT4 in the placenta (p < 0.05). These results suggested that dietary genistin supplementation during gestation can improve the reproductive performance of sows, which was probably associated with improving of antioxidant capacity and immunity, as well as changes of transcript abundance of critical functional genes in the placenta.

Association Between Composite Dietary Antioxidant Index and Endometriosis from NHANES 2001-2006: A Cross-Sectional Study

Purpose

To evaluate the association between Composite Dietary Antioxidant Index (CDAI) and the risk of endometriosis in American women.

Methods

The study adopted a cross-sectional design, incorporating 3862 women aged over 20 years, selected from the National Health and Nutrition Examination Survey (NHANES) dataset from 2001 to 2006. Six dietary antioxidants were taken into account in calculating CDAI. Endometriosis was determined based on self-report. To evaluate the association between CDAI and the risk of endometriosis, we employed models with multivariable logistic variables. For subgroup assessment in relation to CDAI, a stratified multivariate logistic regression model was utilized.

Results

Among all participants, 273 participants (7.1%) were found to exhibit endometriosis. The preliminary analysis showed a reverse association between CDAI and the likelihood of endometriosis (odds ratio [OR] = 0.95; 95% confidence interval [CI]: 0.92~0.98). Upon full adjustment within the multivariable logistic regression, the ORs (95% CI) for endometriosis prevalence per unit increase in CDAI were estimated to be 0.96 (0.93~1). When the CDAI levels were divided into quartiles, it was found that the ORs for endometriosis with CDAI levels in Q2 (-2.131-0.023), Q3 (0.023-2.650), and Q4 (2.650-42.854) were 0.74 (0.52, 1.05), 0.76 (0.53, 1.1), and 0.53 (0.36, 0.79), respectively, compared to those with CDAI levels in Q1 (-7.151--2.131). We evaluated the association between CDAI and endometriosis using subgroups stratified by age, race/ethnicity, education level, body mass index (BMI), oral contraceptive, and menopausal status, revealing a substantial negative relationship.

Conclusion

In this cross-sectional study, increasing CDAI was proportionally associated with a reduced risk of endometriosis among American women, suggesting a diet high in antioxidants may play an important role in reducing the risk of endometriosis. The findings of NHANES data spanning 2001 to 2006 suggest that promoting antioxidant-rich diets could be an important prevention strategy for endometriosis.

Polystyrene microplastics and di-2-ethylhexyl phthalate co-exposure: Implications for female reproductive health

Microplastics and phthalates are prevalent and emerging pollutants that pose a potential impact on human health. Previous studies suggest that both microplastics and phthalates can adversely affect the reproductive systems of humans and mammals. However, the combined impact of these pollutants on the female reproductive system remains unclear. Here we show the impacts of exposure to polystyrene microplastics (PS-MPs) and di-2-ethylhexyl phthalate (DEHP) on female Sprague-Dawley rats' reproductive systems. We find that co-exposure to PS-MPs and DEHP results in a marked increase in cystic and atretic follicles, oxidative stress, fibrosis, and dysregulation of serum sex hormone homeostasis in the ovaries of the rats. Proteomic analysis identified differentially expressed proteins that were predominantly enriched in signaling pathways related to fatty acid metabolism and tight junctions, regulated by transforming growth factor β1 (TGF-β1). We further confirm that co-exposure to DEHP and PS-MPs activates the TGF-β1/Smad3 signaling pathway, and inhibiting this pathway alleviates oxidative stress, hormonal dysregulation, and ovarian fibrosis. These results indicate that exposure to the combination of microplastics and phthalates leads to a significant increase in atretic follicles and may increase the risk of polycystic ovary syndrome (PCOS). Our study provides new insights into the reproductive toxicity effects of microplastics and DEHP exposure on female mammals, highlighting the potential link between environmental pollutants and the occurrence of PCOS. These findings highlight the need for comprehensive assessments of the reproductive health risks posed by microplastic pollution to women and contribute to the scientific basis for evaluating such risks.

FOXM1 affects oxidative stress, mitochondrial function, and the DNA damage response by regulating p21 in aging oocytes

Fertilization capacity and embryo survival rate are decreased in postovulatory aging oocytes, which results in a reduced reproductive rate in female animals. However, the key regulatory genes and related regulatory mechanisms involved in the process of postovulatory aging in oocytes remain unclear. In this study, RNA-Seq revealed that 3237 genes were differentially expressed in porcine oocytes between the MII and aging stages (MII + 24 h). The expression level of FOXM1 was increased at the aging stage, and FOXM1 was also observed to be enriched in many key biological processes, such as cell senescence, response to oxidative stress, and transcription, during porcine oocyte aging. Previous studies have shown that FOXM1 is involved in the regulation of various biological processes, such as oxidative stress, DNA damage repair, mitochondrial function, and cellular senescence, which suggests that FOXM1 may play a crucial role in the process of postovulatory aging. Therefore, in this study, we investigated the effects and mechanisms of FOXM1 on oxidative stress, mitochondrial function, DNA damage, and apoptosis during oocyte aging. Our study revealed that aging oocytes exhibited significantly increased ROS levels and significantly decreased GSH, SOD, T-AOC, and CAT levels than did oocytes at the MII stage and that FOXM1 inhibition exacerbated the changes in these levels in aging oocytes. In addition, FOXM1 inhibition increased the levels of DNA damage, apoptosis, and cell senescence in aging oocytes. A p21 inhibitor alleviated the effects of FOXM1 inhibition on oxidative stress, mitochondrial function, and DNA damage and thus alleviated the degree of senescence in aging oocytes. These results indicate that FOXM1 plays a crucial role in porcine oocyte aging. This study contributes to the understanding of the function and mechanism of FOXM1 during porcine oocyte aging and provides a theoretical basis for preventing oocyte aging and optimizing conditions for the in vitro culture of oocytes.

Proanthocyanidins protects 3-NPA-induced ovarian function decline by activating SESTRIN2-NRF2-mediated oxidative stress in mice

Abnormal apoptosis of ovarian cells caused by oxidative stress is an important cause of premature ovarian failure (POF). Previous studies revealed that proanthocyanidins (PCs) are powerful natural antioxidants that can safely prevent oxidative damage in humans. However, the protective effect and mechanism of PCs on ovarian function during the course of POF remain unknown. In this study, female mice were injected with 3-nitropropionic acid (3-NPA) to establish an ovarian oxidative stress model; at the same time, the mice were treated with PC via gavage. Thereafter, the expression of various apoptosis genes, hormones, and related molecules was assessed. Compared with those in the control group, the ovarian index, follicle count at all levels, expression of MVH, PCNA and BCL2, and estradiol (E2) and progesterone (P) levels were significantly lower in the POF group, but significant recovery was observed in terms of MVH and PCNA expression and E2 and P levels in the POF + PCs group. The apoptosis marker genes BAX and ROS were significantly increased in the POF group but were notably restored in the POF + PCs group. In addition, the expression of Sestrin2, an antiapoptotic protein, was significantly increased in the PCs treatment group, as were the upstream and downstream regulatory factors NRF2 and SOD2, and the indices of the Sestrin2 overexpression group were similar to those of the PCs treatment group. In summary, these findings suggest that PCs have potential as innovative therapeutic agents for preventing and treating POF by activating the protective SESTRIN2-NRF2 pathway against oxidative stress.

Follicle-intrinsic and spatially distinct molecular programs drive follicle rupture and luteinization during ex vivo mammalian ovulation

During ovulation, the apical wall of the preovulatory follicle breaks down to facilitate gamete release. In parallel, the residual follicle wall differentiates into a progesterone-producing corpus luteum. Disruption of ovulation, whether through contraceptive intervention or infertility, has implications for women's health. In this study, we harness the power of an ex vivo ovulation model and machine-learning guided microdissection to identify differences between the ruptured and unruptured sides of the follicle wall. We demonstrate that the unruptured side exhibits clear markers of luteinization after ovulation while the ruptured side exhibits cell death signals. RNA-sequencing of individual follicle sides reveals 2099 differentially expressed genes (DEGs) between follicle sides without ovulation induction, and 1673 DEGs 12 h after induction of ovulation. Our model validates molecular patterns consistent with known ovulation biology even though this process occurs in the absence of the ovarian stroma, vasculature, and immune cells. We further identify previously unappreciated pathways including amino acid transport and Jag-Notch signaling on the ruptured side and glycolysis, metal ion processing, and IL-11 signaling on the unruptured side of the follicle. This study yields key insights into follicle-inherent, spatially-defined pathways that underlie follicle rupture, which may further understanding of ovulation physiology and advance women's health.

Association of diabetes mellitus with risk of reproductive impairment in females: A comprehensive review

Reproductive impairment is the most prevalent yet most ignored complication of diabetes mellitus. In diabetes, the problem associated with reproductive health is comprehensive in both males and females. Diabetic females have problems like delayed menarche, irregular menstrual cycle, subfertility, complications in pregnancy and early menopause. This may decrease reproductive age in diabetic females as the menarche is delayed and menopause is early in them. Like diabetic males, diabetic females also have the negative effect of oxidative stress on the reproductive system. This may lead to dysfunction of the ovary. It affects the physiological cycle like the ovary's maturation, embryo development and pregnancy. These complications also affect the offspring, and they may also become diabetic. This review aims to concentrate on the effect of diabetes on the reproductive system of females and the impairment caused by it. We will also discuss in detail the role of the hypothalamus-pituitary ovary axis, diabetes impact on different reproductive phases of females, and the sexual disorders that occur in them.

Impact of dietary antioxidants on female infertility risk: evidence from NHANES

The composite dietary antioxidant index (CDAI) serves as a valuable instrument for evaluating the intake of dietary antioxidants. This research aims to clarify the connection between CDAI and the risk of female infertility by analyzing data from the National Health and Nutrition Examination Survey from 2013 to 2018. Participants underwent two 24-h dietary recall interviews to calculate CDAI. Female infertility was determined through two questionnaires. Logistic regression model, restricted cubic spline and subgroup analysis were employed to examine the association between CDAI and female infertility. The study encompassed 2162 participants. Participants with female infertility had lower CDAI levels compared to those without. Following adjustment for confounding variables, a negative association between CDAI levels and female infertility was observed (Q4 vs. Q1, OR [95% CI] 0.392 [0.193, 0.795], P = 0.016). RCS demonstrated a statistically significant linear negative relationship between CDAI and female infertility. Subgroup analysis showed no significant interaction. This study illustrates a negative link between the CDAI and female infertility, indicating that higher consumption of dietary antioxidants may be associated with a reduced risk of female infertility. Additional rigorously designed prospective studies are necessary to validate these results.