Endonuclease G is dispensable for sperm mitochondrial DNA elimination during spermatogenesis in mice

Maternal inheritance of mitochondrial DNA (mtDNA) is a widespread phenomenon in eukaryotes. Our earlier research indicated that sperm mtDNA is removed prior to fertilization in mice, and Endonuclease G (ENDOG) orchestrates the degradation of sperm mitochondria in Caenorhabditis elegans. However, the mechanisms underlying sperm mtDNA disposal in mammals remain poorly understood. To investigate the potential role of ENDOG in sperm mtDNA elimination, we created Endog knockout (Endog-/-) mice. Our findings revealed that Endog-/- mice maintained normal spermatogenesis and fertility. Most strikingly, we detected no substantial discrepancy in sperm mtDNA copy number between Endog-/- and control mice. Furthermore, we noted that sperm mtDNA copy numbers were unchanged in both less motile and motile sperm isolated by Percoll gradient centrifugation from Endog-/- and control mice. Taken together, our results indicate that ENDOG is not essential for spermatogenesis or the elimination of sperm mtDNA in mice.

Habitual Daily Intake of Fried Foods Raises Transgenerational Inheritance Risk of Heart Failure Through NOTCH1-Triggered Apoptosis

Consumption of fried foods is highly prevalent in the Western dietary pattern. Western diet has been unfavorably linked with high risk of developing cardiovascular diseases. Heart failure (HF) as a cardiovascular disease subtype is a growing global pandemic with high morbidity and mortality. However, the causal relationship between long-term fried food consumption and incident HF remains unclear. Our population-based study revealed that frequent fried food consumption is strongly associated with 15% higher risk of HF. The causal relationship may be ascribed to the dietary acrylamide exposure in fried foods. Further cross-sectional study evidenced that acrylamide exposure is associated with an increased risk of HF. Furthermore, we discover and demonstrate that chronic acrylamide exposure may induce HF in zebrafish and mice. Mechanistically, we reveal that acrylamide induces energy metabolism disturbance in heart due to the mitochondria dysfunction and metabolic remodeling. Moreover, acrylamide exposure induces myocardial apoptosis via inhibiting NOTCH1-phosphatidylinositol 3-kinase/AKT signaling. In addition, acrylamide exposure could affect heart development during early life stage, and the adverse effect of acrylamide exposure is a threat for next generation via epigenetic change evoked by DNA methyltransferase 1 (DNMT1). In this study, we reveal the adverse effects and underlying mechanism of fried foods and acrylamide as a typical food processing contaminant on HF from population-based observations to experimental validation. Collectively, these results both epidemiologically and mechanistically provide strong evidence to unravel the mechanism of acrylamide-triggered HF and highlight the significance of reducing fried food consumption for lower the risk of HF.

Melatonin improves mouse oocyte quality from 2-ethylhexyl diphenyl phosphate-induced toxicity by enhancing mitochondrial function

2-Ethylhexyl diphenyl phosphate (EHDPP) is a representative organophosphorus flame retardant (OPFR) that has garnered attention due to its widespread use and potential adverse effects. EHDPP exhibits cytotoxicity, genotoxicity, developmental toxicity, and endocrine disruption. However, the toxicity of EHDPP in mammalian oocytes and the underlying mechanisms remain poorly understood. Melatonin is a natural free radical scavenger that has demonstrated cytoprotective properties. In this study, we investigated the effect of EHDPP on mouse oocytes in vitro culture system and evaluated the rescue effect of melatonin on oocytes exposed to EHDPP. Our results indicated that EHDPP disrupted oocyte maturation, resulting in the majority of oocytes arrested at the metaphase I (MI) stage, accompanied by cytoskeletal damage and elevated levels of reactive oxygen species (ROS). Nevertheless, melatonin supplementation partially rescued EHDPP-induced mouse oocyte maturation impairment. Results of single-cell RNA sequencing (scRNA-seq) analysis elucidated potential mechanisms underlying these protective effects. According to the results of scRNA-seq, we conducted further tests and found that EHDPP primarily disrupts mitochondrial distribution and function, kinetochore-microtubule (K-MT) attachment, DNA damage, apoptosis, and histone modification, which were rescued upon the supplementation of melatonin. This study reveals the mechanisms of EHDPP on female reproduction and indicates the efficacy of melatonin as a therapeutic intervention for EHDPP-induced defects in mouse oocytes.

The Efficacy of Letrozole Co-Treatment in an Antagonist Protocol for Women with Polycystic Ovary Syndrome Undergoing IVF: A Retrospective Study

Objective

Our objective was to investigate the efficacy of letrozole co-treatment in an antagonist protocol for infertile women with polycystic ovary syndrome (PCOS).

Patients and Methods

This retrospective cohort study included infertile women with PCOS undergoing IVF/ICSI with and without letrozole co-treatment in an antagonist protocol from 2007-2021 at Shanghai Ninth People's Hospital (Shanghai, China). A total of 1559 participants were enrolled, with 1227 women in the antagonist group and 332 women in the letrozole co-treatment group. Propensity score-based patient-matching model was conducted to balance covariates between the groups. The primary outcome was the number of retrieved oocytes, with secondary outcomes including endocrine parameters, ovarian stimulation outcomes, pregnancy outcomes, and obstetrical and neonatal complications.

Results

Letrozole co-treatment induced significant changes in hormonal regulation, increased the percentage of large follicles, and resulted in fewer retrieved oocytes (P < 0.05). However, there was no negative impact on the number of usable embryos or good-quality embryos (P > 0.05). The live birth rates following fresh embryo transfer were comparable between the letrozole and control groups (single embryo transfer: 28.9% vs 29.7%, P > 0.05; double embryo transfer: 37.3% vs 45.6%, P > 0.05). Additionally, there were no significant differences between the two groups in the live birth rate per patient after frozen embryo transfer and the cumulative live birth rate (P > 0.05). No significant differences in obstetrical and neonatal complications were observed between the groups (P > 0.05).

Conclusion

The addition of letrozole to the antagonist protocol for women with PCOS undergoing IVF induces a higher percentage of large follicles during oocyte retrieval, while reducing the overall number of retrieved oocytes. Moreover, the use of letrozole demonstrates comparable clinical outcomes following embryo transfers. These findings highlight the potential application of letrozole in an antagonist protocol for women with PCOS.

Participation of preovulatory follicles in the activation of primordial follicles in mouse ovaries

The mechanisms behind the selection and initial recruitment of primordial follicles (PmFs) from the non-growing PmF pool during each estrous cycle in females remain largely unknown. This study demonstrates that PmFs closest to the ovulatory follicle are preferentially activated in mouse ovaries under physiological conditions. PmFs located within 40 μm of the ovulatory follicles were more likely to be activated compared to those situated further away during the peri-ovulation period. Repeated superovulation treatments accelerated the depletion of the PmF reserve, whereas continuous suppression of ovulation delayed PmF reserve consumption. Spatial transcriptome sequencing of peri-ovulatory follicles revealed that ovulation primarily induces the degradation and remodeling of the extracellular matrix (ECM). This ECM degradation reduces mechanical stress around PmFs, thereby triggering their activation. Specifically, Cathepsin L (CTSL), a cysteine proteinase and lysosomal enzyme involved in ECM degradation, initiates the activation of PmFs adjacent to ovulatory follicles in a distance-dependent manner. These findings highlight the link between ovulation and selective PmF activation, and underscore the role of CTSL in this process under physiological conditions.

Egg multivesicular bodies elicit an LC3-associated phagocytosis-like pathway to degrade paternal mitochondria after fertilization

Mitochondria are maternally inherited, but the mechanisms underlying paternal mitochondrial elimination after fertilization are far less clear. Using Drosophila, we show that special egg-derived multivesicular body vesicles promote paternal mitochondrial elimination by activating an LC3-associated phagocytosis-like pathway, a cellular defense pathway commonly employed against invading microbes. Upon fertilization, these egg-derived vesicles form extended vesicular sheaths around the sperm flagellum, promoting degradation of the sperm mitochondrial derivative and plasma membrane. LC3-associated phagocytosis cascade of events, including recruitment of a Rubicon-based class III PI(3)K complex to the flagellum vesicular sheaths, its activation, and consequent recruitment of Atg8/LC3, are all required for paternal mitochondrial elimination. Finally, lysosomes fuse with strings of large vesicles derived from the flagellum vesicular sheaths and contain degrading fragments of the paternal mitochondrial derivative. Given reports showing that in some mammals, the paternal mitochondria are also decorated with Atg8/LC3 and surrounded by multivesicular bodies upon fertilization, our findings suggest that a similar pathway also mediates paternal mitochondrial elimination in other flagellated sperm-producing organisms.

Melatonin improves fertilization rate in assisted reproduction: Systematic review and meta-analysis

BACKGROUND

Melatonin is a hormone produced by the pineal gland and it has antioxidant properties.

AIM

This study aimed to evaluate the effects of melatonin on assisted reproductive technologies through a systematic review and a meta-analysis.

MATERIALS AND METHODS

Search strategies were used in PubMed and in other databases covering the last 15 years. After screening for eligibility, 17 articles were selected for the systematic review. For the meta-analysis statistics, two groups were formed, the treatment group (with melatonin) and the control group (without melatonin) for various assisted reproduction outcomes.

RESULTS

The main results were that no statistical differences were found concerning the clinical pregnancy outcome (p = 0.64), but there was a statistical difference with respect to Mature Oocytes (MII) (p = 0.001), antral follicle count (p = 0.0002), and the fertilization rate (p ≤ 0.0001).

CONCLUSIONS

Melatonin had beneficial effects such as the improvement in the fertilization rate, although the authors did not obtain significance in the clinical pregnancy rate.

Glyphosate modifies the gene expression and migration of trophoblastic cells without altering the process of angiogenesis or the implantation of blastocysts in vitro

Adverse pregnancy outcomes have been associated with the presence of glyphosate (G) in umbilical cord, serum, and urine samples from pregnant women. Our aim was to study the effect of G on blastocyst implantation using an in vitro mouse model, and the migration and acquisition of endothelial phenotype of the human trophoblastic HTR8/SVneo (H8) cells. In mouse blastocysts, no differences in attachment time and implantation outgrowth area were observed after G exposure. H8 cell migration was stimulated by 0.625 μM G without cytotoxicity. After 6 h, the mRNA expression of vascular endothelial growth factor (VEGF) and C-C motif chemokine ligand 2 (CCL2) was upregulated in H8 cells exposed to 1.25 μM G when compared vehicle-treated cells (p ≤ 0.05). No differences were observed in interleukin 11, VEGF receptor 1, and coagulation factor II thrombin receptor in H8 cells exposed to different concentrations of G for 6 h compared to the vehicle. Interestingly, exposure to G did not alter angiogenesis as measured by a tube formation assay. Taken all together, these results suggest that G exposure may contribute as a risk factor during pregnancy, due to its ability to alter trophoblast migration and gene expression.

Obstetrical and neonatal outcomes after vitrified-warmed blastocyst transfer in day 1 rescue intracytoplasmic sperm injection cycles: a retrospective cohort study

BACKGROUND

Fertilization failure often occurs in conventional IVF cycles, and day 1 rescue ICSI is frequently recommended. In this study, the effect of rescue ICSI on obstetrical and neonatal outcomes after a single blastocyst transfer in vitrified-warmed cycles is evaluated.

METHODS

This cohort study was a retrospective analysis of 703 vitrified-warmed single blastocyst transfers and 219 singletons in the r-ICSI group compared with 11,611 vitrified-warmed single blastocyst transfers in the IVF/ICSI and 4472 singletons in the IVF/ICSI group, respectively, and patients just undergoing their first IVF treatments were included in this study. Pregnancy rate (PR), live birth rate (LBR), and singleton birthweight were the primary outcome measures. Multiple linear regression analysis and logistic regression analysis were performed to evaluate the possible relationship between obstetrical and neonatal outcomes and fertilization method (including IVF, ICSI, and r-ICSI) after adjusting for other potential confounding factors.

RESULTS

PR and the LBR were lower in the r-ICSI group compared with the IVF/ ICSI group. Singletons from the r-ICSI group had a higher Z-score and the proportion of large for gestational age (LGA) newborns was greater compared with singletons from the IVF/ICSI group.

CONCLUSION

The results of the study indicated that a 31% LBR after r-ICSI is acceptable for vitrified-warmed blastocyst transfer, but the safety of transfer is a concern because of the lower PR and LBR compared with IVF/ICSI. The safety of r-ICSI newborns is also a concern because of the significantly higher birthweight and the proportion of LGA in r-ICSI group newborns compared with the IVF/ICSI group.

Bushen Huoxue recipe ameliorates ovarian function via promoting BMSCs proliferation and homing to ovaries in POI mice

BACKGROUND

Premature ovarian insufficiency (POI) is a tricky puzzle in the field of female reproductive medicine. Bushen Huoxue recipe (BHR), a traditional Chinese medicine compound based on the combination of kidney-tonifying and blood-activating functions, has shown excellent efficacy in improving female irregular menstruation, POI, and infertility. However, the potential mechanism of BHR in POI treatment has not yet been elucidated. Bone marrow mesenchymal stem cells (BMSCs), a type of pluripotent stem cells, have received increasing attention for their significant role in improving ovarian function and restoring fertility in women with POI.

PURPOSE

This study aimed to evaluate the therapeutic effect of BHR in POI mice and explore its potential mechanism.

METHODS

A POI mouse model was established with a single intraperitoneal injection of 120 mg/kg cyclophosphamide (CTX). Distilled water, BHR, or dehydroepiandrosterone was administered via gavage for 28 consecutive days. The effect of BHR on ovarian function in POI mice was evaluated by assessing the estrous cycle, ovarian morphology, follicular development, hormone levels, and angiogenesis. The proportion of BMSCs in bone marrow, peripheral blood, and ovary was analyzed via flow cytometry, and the level of molecules mediating migration and homing in ovary was measured. Cell viability assays, scratch healing assays and transwell migration assays were performed to explore the effect of BHR on BMSCs proliferation and migration in vitro, and its potential mechanism was explored.

RESULTS

BHR significantly ameliorated estrous cycle disorders, hormone disorders, ovarian morphology, ovarian microvascular formation, and ovarian reserve in POI mice. Meanwhile, the number of BMSCs number in the bone marrow, peripheral blood, and ovary was apparently increased. Of note, BHR increased the level of hepatocyte growth factor (HGF)/cellular mesenchymal epithelial transition factor (cMET) and stromal cell-derived factor-1(SDF-1)/CXC chemokine receptor 4 (CXCR4) in the ovaries of POI mice. Moreover, BHR treatment promoted BMSCs proliferation and migration in vitro, with a significant increase in the level of proliferating cell nuclear antigen, cMET, and CXCR4.

CONCLUSIONS

BHR effectively restored ovarian reserve, ovarian function, and ovarian angiogenesis in CTX-induced POI mice. In addition, BHR promoted BMSCs proliferation, migration, and homing to the ovary, which was mediated by the SDF-1/CXCR4 and HGF/cMET signaling axis. Finally, the amelioration of ovarian reserve and ovarian function in CTX-induced POI mice by BHR may be related to its promotion of endogenous BMSCs proliferation and homing.

C-Phycocyanin improves the quality of goat oocytes after in vitro maturation and vitrification

In vitro maturation (IVM) and cryopreservation of goat oocytes are important for establishing a valuable genetic bank for domesticated female animals and improving livestock reproductive efficiency. C-Phycocyanin (PC) is a Spirulina extract with antioxidant, antiinflammatory, and radical scavenging properties. However, whether PC has positive effect on goat oocytes IVM or developmental competence after vitrification is still unknown. In this study, we found that first polar body extrusion (n = 293), cumulus expansion index (n = 269), and parthenogenetic blastocyst formation (n = 281) were facilitated by adding 30 μg/mL PC to the oocyte maturation medium when compared with the control groups and that supplemented with 3, 10, 100 or 300 μg/mL PC (P < 0.05). Although PC supplementation did not affect spindle formation or chromosome alignment (n = 115), it facilitated or improved cortical granules migration (n = 46, P < 0.05), mitochondria distribution (n = 39, P < 0.05), and mitochondrial membrane potential (n = 46, P < 10-4). Meanwhile, supplementation with 30 μg/mL PC in the maturation medium could significantly inhibit the reactive oxygen species accumulation (n = 65, P < 10-4), and cell apoptosis (n = 42, P < 0.05). In addition, PC increased the oocyte mRNA levels of GPX4 (P < 0.01), and decreased the mRNA and protein levels of BAX (P < 0.01). Next, we investigated the effect of PC supplementation in the vitrification solution on oocyte cryopreservation. When compared with the those equilibrate in the vitrification solution without PC, recovered oocytes in the 30 μg/mL PC group showed higher ratios of normal morphology (n = 85, P < 0.05), survival (n = 85, P < 0.05), first polar body extrusion (n = 62, P < 0.05), and parthenogenetic blastocyst formation (n = 107, P < 0.05). Meanwhile, PC supplementation of the vitrification solution increased oocyte mitochondrial membrane potential (n = 53, P < 0.05), decreased the reactive oxygen species accumulation (n = 73, P < 0.05), promoted mitochondria distribution (n = 58, P < 0.05), and inhibited apoptosis (n = 46, P < 10-3). Collectively, our findings suggest that PC improves goat oocyte IVM and vitrification by reducing oxidative stress and early apoptosis, which providing a novel strategy for livestock gamete preservation and utilization.

Evaluation of viability, developmental competence, and apoptosis-related transcripts during in vivo post-ovulatory oocyte aging in zebrafish Danio rerio (Hamilton, 1822)

Introduction

Post-ovulatory aging is a time-dependent deterioration of ovulated oocytes and a major limiting factor reducing the fitness of offspring. This process may lead to the activation of cell death pathways like apoptosis in oocytes.

Methodology

We evaluated oocyte membrane integrity, egg developmental competency, and mRNA abundance of apoptosis-related genes by RT-qPCR. Oocytes from zebrafish Danio rerio were retained in vivo at 28.5°C for 24 h post-ovulation (HPO). Viability was assessed using trypan blue (TB) staining. The consequences of in vivo oocyte aging on the developmental competence of progeny were determined by the embryo survival at 24 h post fertilization, hatching, and larval malformation rates.

Results

The fertilization, oocyte viability, and hatching rates were 91, 97, and 65% at 0 HPO and dropped to 62, 90, and 22% at 4 HPO, respectively. The fertilizing ability was reduced to 2% at 8 HPO, while 72% of oocytes had still intact plasma membranes. Among the apoptotic genes bcl-2 (b-cell lymphoma 2), bada (bcl2-associated agonist of cell death a), cathepsin D, cathepsin Z, caspase 6a, caspase 7, caspase 8, caspase 9, apaf1, tp53 (tumor protein p53), cdk1 (cyclin-dependent kinase 1) studied, mRNA abundance of anti-apoptotic bcl-2 decreased and pro-apoptotic cathepsin D increased at 24 HPO. Furthermore, tp53 and cdk1 mRNA transcripts decreased at 24 HPO compared to 0 HPO.

Discussion

Thus, TB staining did not detect the loss of oocyte competency if caused by aging. TB staining, however, could be used as a simple and rapid method to evaluate the quality of zebrafish oocytes before fertilization. Taken together, our results indicate the activation of cell death pathways in the advanced stages of oocyte aging in zebrafish.

Emerging Multi-omic Approaches to the Molecular Diagnosis of Mitochondrial Disease and Available Strategies for Treatment and Prevention

Mitochondria are semi-autonomous organelles present in several copies within most cells in the human body that are controlled by the precise collaboration of mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) encoding mitochondrial proteins. They play important roles in numerous metabolic pathways, such as the synthesis of adenosine triphosphate (ATP), the predominant energy substrate of the cell generated through oxidative phosphorylation (OXPHOS), intracellular calcium homeostasis, metabolite biosynthesis, aging, cell cycles, and so forth. Previous studies revealed that dysfunction of these multi-functional organelles, which may arise due to mutations in either the nuclear or mitochondrial genome, leads to a diverse group of clinically and genetically heterogeneous disorders. These diseases include neurodegenerative and metabolic disorders as well as cardiac and skeletal myopathies in both adults and newborns. The plethora of phenotypes and defects displayed leads to challenges in the diagnosis and treatment of mitochondrial diseases. In this regard, the related literature proposed several diagnostic options, such as high throughput mitochondrial genomics and omics technologies, as well as numerous therapeutic options, such as pharmacological approaches, manipulating the mitochondrial genome, increasing the mitochondria content of the affected cells, and recently mitochondrial diseases transmission prevention. Therefore, the present article attempted to review the latest advances and challenges in diagnostic and therapeutic options for mitochondrial diseases.

The role of mitochondrial dynamics in oocyte and early embryo development

Mitochondrial dysfunction is widely implicated in various human diseases, through mechanisms that go beyond mitochondria's well-established role in energy generation. These dynamic organelles exert vital control over numerous cellular processes, including calcium regulation, phospholipid synthesis, innate immunity, and apoptosis. While mitochondria's importance is acknowledged in all cell types, research has revealed the exceptionally dynamic nature of the mitochondrial network in oocytes and embryos, finely tuned to meet unique needs during gamete and pre-implantation embryo development. Within oocytes, both the quantity and morphology of mitochondria can significantly change during maturation and post-fertilization. These changes are orchestrated by fusion and fission processes (collectively known as mitochondrial dynamics), crucial for energy production, content exchange, and quality control as mitochondria adjust to the shifting energy demands of oocytes and embryos. The roles of proteins that regulate mitochondrial dynamics in reproductive processes have been primarily elucidated through targeted deletion studies in animal models. Notably, impaired mitochondrial dynamics have been linked to female reproductive health, affecting oocyte quality, fertilization, and embryo development. Dysfunctional mitochondria can lead to fertility problems and can have an impact on the success of pregnancy, particularly in older reproductive age women.

The mechanism of curcumin to protect mouse ovaries from oxidative damage by regulating AMPK/mTOR mediated autophagy

BACKGROUND

Oxidative stress is considered the main cause of granulosa cell apoptosis in ovarian disease. Curcumin has various biological roles, but its potential role in protecting granulosa cells from oxidative damage remains unidentified.

PURPOSE

The study revealed the protective effect of curcumin on granulosa cell survival under oxidative stress, and explored its mode of action.

STUDY DESIGN

The protective effect of curcumin on oxidative stress-induced ovarian cell apoptosis was evaluated in vivo and in vitro, and the role of autophagy and AMPK/mTOR signaling pathway in this process was also demonstrated.

METHODS

First, mice were injected to 3-nitropropionic acid (3-NPA, 20 mg/kg/day) for 14 consecutive days to establish the ovarian oxidative stress model, at same time, curcumin (50, 100, 200 mg/kg/day) was given orally. Thereafter, functional changes, cell apoptosis, and autophagy in ovarian tissue were evaluated by hematoxylin-eosin staining, enzyme-linked immunosorbent assay, western blotting, TUNEL assays, and transmission electron microscopy. Finally, oxidative stress model of granulosa cells was established with H2O2in vitro and treated with curcumin. The underlying mechanisms of curcumin to protect the apoptosis under oxidative stress in vitro were determined using western blotting and TUNEL assays.

RESULTS

In our study, after curcumin treatment, the mouse ovarian function disorder under 3-nitropropionic acid-induced oxidative stress recovered significantly, and ovarian cell apoptosis decreased. H2O2 induced granulosa cell apoptosis in vitro, and curcumin antagonized this process. Autophagy contributes to tissue and cell survival under stress. We therefore examined the role of autophagy in this process. According to the in vivo and in vitro results, curcumin restored autophagy under oxidative stress. The autophagy inhibitor (chloroquine) exhibited the same effect as curcumin, whereas the autophagy activator (rapamycin) antagonized the effect of curcumin. In addition, the study found that the AMPK/mTOR pathway plays a crucial role in curcumin- mediated autophagy to protect against oxidative stress-induced apoptosis.

CONCLUSION

Our findings for the first time systematically revealed a new mechanism through which curcumin protects ovarian granulosa cells from oxidative stress-induced damage through AMPK/mTOR-mediated autophagy and suggested that it can be a new therapeutic direction for female ovarian diseases.

Ovarian aging: energy metabolism of oocytes

In women who are getting older, the quantity and quality of their follicles or oocytes and decline. This is characterized by decreased ovarian reserve function (DOR), fewer remaining oocytes, and lower quality oocytes. As more women choose to delay childbirth, the decline in fertility associated with age has become a significant concern for modern women. The decline in oocyte quality is a key indicator of ovarian aging. Many studies suggest that age-related changes in oocyte energy metabolism may impact oocyte quality. Changes in oocyte energy metabolism affect adenosine 5'-triphosphate (ATP) production, but how related products and proteins influence oocyte quality remains largely unknown. This review focuses on oocyte metabolism in age-related ovarian aging and its potential impact on oocyte quality, as well as therapeutic strategies that may partially influence oocyte metabolism. This research aims to enhance our understanding of age-related changes in oocyte energy metabolism, and the identification of biomarkers and treatment methods.

A non-antibiotic antimicrobial drug, a biological bacteriostatic agent, is useful for treating aerobic vaginitis, bacterial vaginosis, and vulvovaginal candidiasis

BACKGROUND

Vaginitis is a common infection in women, with approximately 75% of women experiencing at least one episode during their lifetime. Although antimicrobial agents are widely used to treat vaginitis, recurrent vaginitis occurs in some patients. Resistance to these agents is the major cause of recurrent vaginitis. Therefore, there is an urgent need to develop novel drugs.

METHODS

We investigated the efficacy of a new biological bacteriostatic agent (BBA), composed of lysozyme, phytoalexin, chitosan oligosaccharide, sinensetin, 18β/20α-glycyrrhizin, and betaine, against vaginitis using in vitro and in vivo studies. First, we evaluated the antibacterial effects of BBA against 13 microbial strains commonly present in aerobic vaginitis, bacterial vaginosis, vulvovaginal candidiasis, and healthy vaginas. Second, we assessed the safety of various doses of BBA administered orally for 4 weeks in female mice. Third, we examined the in vivo anti-proliferative and anti-inflammatory effects of BBA in Candida albicans-, Candida glabrata-, and Gardnerella-induced vaginitis models. Finally, we evaluated the anti-vaginitis effect of a BBA gel prepared with 0.5% (w/v) ammonium acryloyldimethyltaurate/Vp copolymer.

RESULTS

BBA effectively suppressed the growth of the main causative pathogens of vaginitis in vitro. BBA, either undiluted or diluted two-fold, inhibited all microorganisms cultured for 8 h. No obvious organ damage was detected when BBA was administered to mice. Both BBA alone and 70% BBA in a gel formulation effectively inhibited the proliferation of C. albicans, C. glabrata, and Gardnerella in vaginal lavage samples and alleviated tissue inflammation in mice with vaginitis. The 70% BBA gel performed better than BBA alone at treating vaginitis in mice infected with Gardnerella vaginalis.

CONCLUSION

BBA alone and a 70% BBA gel inhibited the growth of pathogens and effectively alleviated inflammation caused by C. albicans, C. glabrata, and G. vaginalis.

FMNL2 regulates actin for endoplasmic reticulum and mitochondria distribution in oocyte meiosis

During mammalian oocyte meiosis, spindle migration and asymmetric cytokinesis are unique steps for the successful polar body extrusion. The asymmetry defects of oocytes will lead to the failure of fertilization and embryo implantation. In present study, we reported that an actin nucleating factor Formin-like 2 (FMNL2) played critical roles in the regulation of spindle migration and organelle distribution in mouse and porcine oocytes. Our results showed that FMNL2 mainly localized at the oocyte cortex and periphery of spindle. Depletion of FMNL2 led to the failure of polar body extrusion and large polar bodies in oocytes. Live-cell imaging revealed that the spindle failed to migrate to the oocyte cortex, which caused polar body formation defects, and this might be due to the decreased polymerization of cytoplasmic actin by FMNL2 depletion in the oocytes of both mice and pigs. Furthermore, mass spectrometry analysis indicated that FMNL2 was associated with mitochondria and endoplasmic reticulum (ER)-related proteins, and FMNL2 depletion disrupted the function and distribution of mitochondria and ER, showing with decreased mitochondrial membrane potential and the occurrence of ER stress. Microinjecting Fmnl2-EGFP mRNA into FMNL2-depleted oocytes significantly rescued these defects. Thus, our results indicate that FMNL2 is essential for the actin assembly, which further involves into meiotic spindle migration and ER/mitochondria functions in mammalian oocytes.

Impact of Transgenerational Nutrition on Nonalcoholic Fatty Liver Disease Development: Interplay between Gut Microbiota, Epigenetics and Immunity

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most prevalent pediatric liver disorder, primarily attributed to dietary shifts in recent years. NAFLD is characterized by the accumulation of lipid species in hepatocytes, leading to liver inflammation that can progress to steatohepatitis, fibrosis, and cirrhosis. Risk factors contributing to NAFLD encompass genetic variations and metabolic disorders such as obesity, diabetes, and insulin resistance. Moreover, transgenerational influences, resulting in an imbalance of gut microbial composition, epigenetic modifications, and dysregulated hepatic immune responses in offspring, play a pivotal role in pediatric NAFLD development. Maternal nutrition shapes the profile of microbiota-derived metabolites in offspring, exerting significant influence on immune system regulation and the development of metabolic syndrome in offspring. In this review, we summarize recent evidence elucidating the intricate interplay between gut microbiota, epigenetics, and immunity in fetuses exposed to maternal nutrition, and its impact on the onset of NAFLD in offspring. Furthermore, potential therapeutic strategies targeting this network are also discussed.

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

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

Mechanisms of female reproductive toxicity in pigs induced by exposure to environmental pollutants

Environmental pollutants, including endocrine disruptors, heavy metals, nanomaterials, and pesticides, have been detected in various ecosystems and are of growing global concern. The potential for toxicity to non-target organisms has consistently been raised and is being studied using various animal models. In this review, we focus on pesticides frequently detected in the environment and investigate their potential exposure to livestock. Owing to the reproductive similarities between humans and pigs, various in vitro porcine models, such as porcine oocytes, trophectoderm cells, and luminal epithelial cells, are used to verify reproductive toxicity. These cell lines are being used to study the toxic mechanisms induced by various environmental toxicants, including organophosphate insecticides, pyrethroid insecticides, dinitroaniline herbicides, and diphenyl ether herbicides, which persist in the environment and threaten livestock health. Collectively, these results indicate that these pesticides can induce female reproductive toxicity in pigs and suggest the possibility of adverse effects on other livestock species. These results also indicate possible reproductive toxicity in humans, which requires further investigation.

Early embryonic failure caused by a novel mutation in the TUBB8 gene: A case report

BACKGROUND

This study aimed to explore the relationship between gene mutations and early embryonic development arrest and to provide more possibilities for the diagnosis and treatment of repeated implantation failure.

CASE SUMMARY

Here, we collected and described the clinical data of a patient with early embryonic development stagnation after repeated in vitro fertilization attempts for primary infertility at the Department Reproductive Center of Zaozhuang Maternal and Child Healthcare Hospital. We also detected the whole-exon gene of the patient's spouse and parents, and conducted bioinformatics analysis to determine the pathogenesis of the gene.

CONCLUSION

A novel mutant of the TUBB8 gene [c.602G>T(p.C201F)] was identified, and this mutant provided new data on the genotype-phenotype relationships of related diseases.

Nicotinamide Mononucleotide improves oocyte maturation of mice with type 1 diabetes

BACKGROUND

The number of patients with type 1 diabetes rises rapidly around the world in recent years. Maternal diabetes has a detrimental effect on reproductive outcomes due to decreased oocyte quality. However, the strategies to improve the oocyte quality and artificial reproductive technology (ART) efficiency of infertile females suffering from diabetes have not been fully studied. In this study, we aimed to examine the effects of nicotinamide mononucleotide (NMN) on oocyte maturation of mouse with type 1 diabetes mouse and explore the underlying mechanisms of NMN's effect.

METHODS

Streptozotocin (STZ) was used to establish the mouse models with type 1 diabetes. The successful establishment of the models was confirmed by the results of body weight test, fasting blood glucose test and haematoxylin and eosin (H&E) staining. The in vitro maturation (IVM) rate of oocytes from diabetic mice was examined. Immunofluorescence staining (IF) was performed to examine the reactive oxygen species (ROS) level, spindle/chromosome structure, mitochondrial function, actin dynamics, DNA damage and histone modification of oocytes, which are potential factors affecting the oocyte quality. The quantitative reverse transcription PCR (RT-qPCR) was used to detect the mRNA levels of Sod1, Opa1, Mfn2, Drp1, Sirt1 and Sirt3 in oocytes.

RESULTS

The NMN supplementation increased the oocyte maturation rate of the mice with diabetes. Furthermore, NMN supplementation improved the oocyte quality by rescuing the actin dynamics, reversing meiotic defects, improving the mitochondrial function, reducing ROS level, suppressing DNA damage and restoring changes in histone modifications of oocytes collected from the mice with diabetes.

CONCLUSION

NMN could improve the maturation rate and quality of oocytes in STZ-induced diabetic mice, which provides a significant clue for the treatment of infertility of the patients with diabetes.

CRL4DCAF13 E3 ubiquitin ligase targets MeCP2 for degradation to prevent DNA hypermethylation and ensure normal transcription in growing oocytes

The DNA methylation is gradually acquired during oogenesis, a process sustained by successful follicle development. However, the functional roles of methyl-CpG-binding protein 2 (MeCP2), an epigenetic regulator displaying specifical binding with methylated DNA, remains unknown in oogenesis. In this study, we found MeCP2 protein was highly expressed in primordial and primary follicle, but was almost undetectable in secondary follicles. However, in aged ovary, MeCP2 protein is significantly increased in both oocyte and granulosa cells. Overexpression of MeCP2 in growing oocyte caused transcription dysregulation, DNA hypermethylation, and genome instability, ultimately leading to follicle growth arrest and apoptosis. MeCP2 is targeted by DCAF13, a substrate recognition adaptor of the Cullin 4-RING (CRL4) E3 ligase, and polyubiquitinated for degradation in both cells and oocytes. Dcaf13-null oocyte exhibited an accumulation of MeCP2 protein, and the partial rescue of follicle growth arrest induced by Dcaf13 deletion was observed following MeCP2 knockdown. The RNA-seq results revealed that large amounts of genes were regulated by the DCAF13-MeCP2 axis in growing oocytes. Our study demonstrated that CRL4DCAF13 E3 ubiquitin ligase targets MeCP2 for degradation to ensure normal DNA methylome and transcription in growing oocytes. Moreover, in aged ovarian follicles, deceased DCAF13 and DDB1 protein were observed, indicating a potential novel mechanism that regulates ovary aging.

Maternal mitochondrial function affects paternal mitochondrial inheritance in Drosophila

The maternal inheritance of mitochondria is a widely accepted paradigm, and mechanisms that prevent paternal mitochondria transmission to offspring during spermatogenesis and postfertilization have been described. Although certain species do retain paternal mitochondria, the factors affecting paternal mitochondria inheritance in these cases are unclear. More importantly, the evolutionary benefit of retaining paternal mitochondria and their ultimate fate are unknown. Here we show that transplanted exogenous paternal D. yakuba mitochondria can be transmitted to offspring when maternal mitochondria are dysfunctional in D. melanogaster. Furthermore, we show that the preserved paternal mitochondria are functional, and can be stably inherited, such that the proportion of paternal mitochondria increases gradually in subsequent generations. Our work has important implications that paternal mitochondria inheritance should not be overlooked as a genetic phenomenon in evolution, especially when paternal mitochondria are of significant differences from the maternal mitochondria or the maternal mitochondria are functionally abnormal. Our results improve the understanding of mitochondrial inheritance and provide a new model system for its study.

Epigenetic programming for obesity and noncommunicable disease: From womb to tomb

Several epidemiological, clinical and experimental studies in recent decades have shown the relationship between exposure to stressors during development and health outcomes later in life. The characterization of these susceptible phases, such as preconception, gestation, lactation and adolescence, and the understanding of factors that influence the risk of an adult individual for developing obesity, metabolic and cardiovascular diseases, is the focus of the DOHaD (Developmental Origins of Health and Disease) research line. In this sense, advancements in molecular biology techniques have contributed significantly to the understanding of the mechanisms underlying the observed phenotypes, their morphological and physiological alterations, having as a main driving factor the epigenetic modifications and their consequent modulation of gene expression. The present narrative review aimed to characterize the different susceptible phases of development and associated epigenetic modifications, and their implication in the development of non-communicable diseases. Additionally, we provide useful insights into interventions during development to counteract or prevent long-term programming for disease susceptibility.

Epigenetic modifications of placenta in women with gestational diabetes mellitus and their offspring

Gestational diabetes mellitus (GDM) is a pregnancy-related complication characterized by abnormal glucose metabolism in pregnant women and has an important impact on fetal development. As a bridge between the mother and the fetus, the placenta has nutrient transport functions, endocrine functions, etc., and can regulate placental nutrient transport and fetal growth and development according to maternal metabolic status. Only by means of placental transmission can changes in maternal hyperglycemia affect the fetus. There are many reports on the placental pathophysiological changes associated with GDM, the impacts of GDM on the growth and development of offspring, and the prevalence of GDM in offspring after birth. Placental epigenetic changes in GDM are involved in the programming of fetal development and are involved in the pathogenesis of later chronic diseases. This paper summarizes the effects of changes in placental nutrient transport function and hormone secretion levels due to maternal hyperglycemia and hyperinsulinemia on the development of offspring as well as the participation of changes in placental epigenetic modifications due to maternal hyperglycemia in intrauterine fetal programming to promote a comprehensive understanding of the impacts of placental epigenetic modifications on the development of offspring from patients with GDM.

Diminished NAD+ levels and activation of retrotransposons promote postovulatory aged oocyte (POAO) death

Death is the fate of postovulatory aged or unfertilized oocytes (POAO) in many animals. However, precise molecular mechanisms are yet to be discovered. Here, we demonstrate that increased amounts of reactive oxygen species (ROS), calcium ion (Ca+2) channels, and retrotransposon activity induce apoptosis, which in turn causes POAO death. Notably, suppression of ROS, Ca+2 channels, and retrotransposons delayed POAO death. Further, we found that the histone H4K12 and K16 acetylation increased via downregulation of NAD+ and NAD+ -dependent histone deacetylase SIRT3. Furthermore, adding NMN, sodium pyruvate, or CD38 inhibition delayed the death of postovulatory aged oocytes. Finally, we demonstrate the conservation of retrotransposon-induced DNA damage-dependent POAO death in higher-order vertebrates. Our findings suggest that POAO mortality is caused by cyclic cascade metabolic interactions in which low NAD+ levels increase histone acetylation by inhibiting histone deacetylases, resulting in an increase in retrotransposons, ROS, and Ca+2 channel activity and thus contributing to DNA damage-induced apoptosis.

Transcriptome profiling reveals superovulation with the gonadotropin-releasing hormone agonist trigger impaired embryo implantation in mice

Introduction

Superovulation is a critical step in assisted reproductive technology, but the use of human chorionic gonadotropin (hCG) as a trigger for superovulation can result in ovarian hyperstimulation. Thus, the use of Gonadotropin-releasing hormone agonist (GnRHa) trigger has been increasingly adopted, although it has been associated with a higher rate of pregnancy failure compared to natural cycles. This study aimed to investigate the effect of GnRHa trigger on embryo implantation in a mouse model.

Methods

Mice in the superovulation (PG) group were administered 7.5 IU of PMSG, followed by the injection of 3.5 μg of GnRHa (Leuprorelin) 48 h later, while mice in the control group (CTR) mated naturally. We compared the number of oocytes, blastocysts, and corpus luteum between the two groups and the implantation sites after the transfer of natural blastocysts. Ovaries, uterus, and serum 2 and 4 days after mating were collected for qRT-PCR, transcriptome sequencing, and hormone assays.

Results

The PG group had more oocytes, blastocysts, and corpus luteum after superovulation than the CTR group. However, the mRNA expression of leukemia inhibitory factor (Lif) and the number of implantation sites were reduced in the PG group. The ELISA assay revealed that superovulation increased ovarian estrogen secretion. The transcriptome analysis showed that superphysiological estrogen led to a response of the uterus to a high estrogen signal, resulting in abnormal endometrium and extracellular matrix remodeling and up-regulation of ion transport and inflammation-related genes.

Conclusion

Our findings suggest that a combination of PMSG and GnRHa trigger impaired embryo implantation in mice, as the excessive uterine response to superphysiological estrogen levels can lead to the change of gene expression related to endometrial remodeling, abnormal expression of uterine ion transport genes and excessive immune-related genes.

Phytosterol organic acid esters: Characterization, anti-inflammatory properties and a delivery strategy to improve mitochondrial function

Phytosterol organic acid esters are important food resources and the components of biomembrane structure. Due to the lack of extraction and synthesis techniques, more research has been focused on phytosterols, and the research on phytosterol acid esters have encountered a bottleneck, but phytosterol acid esters confer substantial benefits to human health. In this study, stigmasteryl vanillate (VAN), stigmasteryl protocatechuate (PRO) and stigmasteryl sinapate (SIN) were prepared through the Steglich reaction. The processes are promotable and the products reach up to 95% purity. In addition, their stability was evaluated by differential scanning calorimetry and thermogravimetric analysis. HPLC analysis revealed an enhancement in water solubility after esterification with phenolic acid. In an in vitro digestion model, the bioaccessibility of stigmasteryl phenolates was significantly higher than that of stigmasterols (STIs). Regarding the anti-inflammatory properties, VAN, PRO, and SIN exhibit superior effects against TNF-α induced pro-inflammatory responses compared to STI. All stigmasteryl phenolates supplementation increased the ATP production, the basal, and maximal oxygen consumption rate in mitochondrial stress test. Overall, we present a synthesis method for stigmasteryl phenolates. It will contribute to the development and research of phytosterol acid ester analysis, functions and utilization in food. Moreover, the nutrient-stigmasterol hybrids tactic we have constructed is practical and can become a targeted mitochondrial delivery strategy with enhanced anti-inflammatory effects.

Exploring Four Atraphaxis Species: Traditional Medicinal Uses, Phytochemistry, and Pharmacological Activities

Atraphaxis is a genus of flowering plants in the family Polygonaceae, with approximately 60 species. Species of Atraphaxis are much-branched woody plants, forming shrubs or shrubby tufts, primarily inhabiting arid zones across the temperate steppe and desert regions of Central Asia, America, and Australia. Atraphaxis species have been used by diverse groups of people all over the world for the treatment of various diseases. However, their biologically active compounds with therapeutic properties have not been investigated well. Studying the biologically active components of Atraphaxis laetevirens, Atraphaxis frutescens, Atraphaxis spinosa L., and Atraphaxis pyrifolia is crucial for several reasons. Firstly, it can unveil the therapeutic potential of these plants, aiding in the development of novel medicines or natural remedies for various health conditions. Understanding their bioactive compounds enables scientists to explore their pharmacological properties, potentially leading to the discovery of new drugs or treatments. Additionally, investigating these components contributes to preserving traditional knowledge and validating the historical uses of these plants in ethnomedicine, thus supporting their conservation and sustainable utilization. These herbs have been used as an anti-inflammatory and hypertension remedies since the dawn of time. Moreover, they have been used to treat a variety of gastrointestinal disorders and problems related to skin in traditional Kazakh medicine. Hence, the genus Atraphaxis can be considered as a potential medicinal plant source that is very rich in biologically active compounds that may exhibit great pharmacological properties, such as antioxidant, antibacterial, antiulcer, hypoglycemic, wound healing, neuroprotective, antidiabetic, and so on. This study aims to provide a collection of publications on the species of Atraphaxis, along with a critical review of the literature data. This review will constitute support for further investigations on the pharmacological activity of these medicinal plant species.

Preconception Diet Interventions in Obese Outbred Mice and the Impact on Female Offspring Metabolic Health and Oocyte Quality

Obese individuals often suffer from metabolic health disorders and reduced oocyte quality. Preconception diet interventions in obese outbred mice restore metabolic health and oocyte quality and mitochondrial ultrastructure. Also, studies in inbred mice have shown that maternal obesity induces metabolic alterations and reduces oocyte quality in offspring (F1). Until now, the effect of maternal high-fat diet on F1 metabolic health and oocyte quality and the potential beneficial effects of preconception dietary interventions have not been studied together in outbred mice. Therefore, we fed female mice a high-fat/high-sugar (HF/HS) diet for 7 weeks and switched them to a control (CONT) or caloric-restriction (CR) diet or maintained them on the HF/HS diet for 4 weeks before mating, resulting in three treatment groups: diet normalization (DN), CR, and HF/HS. In the fourth group, mice were fed CONT diet for 11 weeks (CONT). HF/HS mice were fed an HF/HS diet from conception until weaning, while all other groups were then fed a CONT diet. After weaning, offspring were kept on chow diet and sacrificed at 11 weeks. We observed significantly elevated serum insulin concentrations in female HF/HS offspring and a slightly increased percentage of mitochondrial ultrastructural abnormalities, mitochondrial size, and mitochondrial mean gray intensity in HF/HS F1 oocytes. Also, global DNA methylation was increased and cellular stress-related proteins were downregulated in HF/HS F1 oocytes. Mostly, these alterations were prevented in the DN group, while, in CR, this was only the case for a few parameters. In conclusion, this research has demonstrated for the first time that a maternal high-fat diet in outbred mice has a moderate impact on female F1 metabolic health and oocyte quality and that preconception DN is a better strategy to alleviate this compared to CR.

Chromosome Division in Early Embryos-Is Everything under Control? And Is the Cell Size Important?

Chromosome segregation in female germ cells and early embryonic blastomeres is known to be highly prone to errors. The resulting aneuploidy is therefore the most frequent cause of termination of early development and embryo loss in mammals. And in specific cases, when the aneuploidy is actually compatible with embryonic and fetal development, it leads to severe developmental disorders. The main surveillance mechanism, which is essential for the fidelity of chromosome segregation, is the Spindle Assembly Checkpoint (SAC). And although all eukaryotic cells carry genes required for SAC, it is not clear whether this pathway is active in all cell types, including blastomeres of early embryos. In this review, we will summarize and discuss the recent progress in our understanding of the mechanisms controlling chromosome segregation and how they might work in embryos and mammalian embryos in particular. Our conclusion from the current literature is that the early mammalian embryos show limited capabilities to react to chromosome segregation defects, which might, at least partially, explain the widespread problem of aneuploidy during the early development in mammals.

Insights into embryonic chromosomal instability: mechanisms of DNA elimination during mammalian preimplantation development

Mammalian preimplantation embryos often contend with aneuploidy that arose either by the inheritance of meiotic errors from the gametes, or from mitotic mis-segregation events that occurred following fertilization. Regardless of the origin, mis-segregated chromosomes become encapsulated in micronuclei (MN) that are spatially isolated from the main nucleus. Much of our knowledge of MN formation comes from dividing somatic cells during tumorigenesis, but the error-prone cleavage-stage of early embryogenesis is fundamentally different. One unique aspect is that cellular fragmentation (CF), whereby small subcellular bodies pinch off embryonic blastomeres, is frequently observed. CF has been detected in both in vitro and in vivo-derived embryos and likely represents a response to chromosome mis-segregation since it only appears after MN formation. There are multiple fates for MN, including sequestration into CFs, but the molecular mechanism(s) by which this occurs remains unclear. Due to nuclear envelope rupture, the chromosomal material contained within MN and CFs becomes susceptible to double stranded-DNA breaks. Despite this damage, embryos may still progress to the blastocyst stage and exclude chromosome-containing CFs, as well as non-dividing aneuploid blastomeres, from participating in further development. Whether these are attempts to rectify MN formation or eliminate embryos with poor implantation potential is unknown and this review will discuss the potential implications of DNA removal by CF/blastomere exclusion. We will also extrapolate what is known about the intracellular pathways mediating MN formation and rupture in somatic cells to preimplantation embryogenesis and how nuclear budding and DNA release into the cytoplasm may impact overall development.

Ultra-Fast Vitrification: Minimizing the Toxicity of Cryoprotective Agents and Osmotic Stress in Mouse Oocyte Cryopreservation

Globally, women have been adopting oocyte cryopreservation (OC) for fertility preservation for various reasons, such as inevitable gonadotoxic treatment for specific pathologic states and social preferences. While conventional vitrification (C-VIT) has improved the success rate of OC, challenges of possible toxicities of high-concentration cryoprotective agents and osmotic stress persist. To overcome these challenges, we evaluated the ultra-fast vitrification (UF-VIT) method, which reduces the equilibration solution stage exposure time compared to C-VIT by observing mouse oocyte intracellular organelles and embryonic development. Consequently, compared to fresh mouse oocytes, UF-VIT presented significant differences only in endoplasmic reticulum (ER) intensity and mitochondrial (MT) distribution. Meanwhile, C-VIT showed substantial differences in the survival rate, key ER and MT parameters, and embryonic development rate. UF-VIT exhibited considerably fewer negative effects on key MT parameters and resulted in a notably higher blastocyst formation rate than C-VIT. Meiotic spindle (spindle and chromosomes) morphology showed no significant changes between the groups during vitrification/warming (VW), suggesting that VW did not negatively affect the meiotic spindle of the oocytes. In conclusion, UF-VIT seems more effective in OC owing to efficient cytoplasmic water molecule extraction, osmotic stress reduction, and minimization of cell contraction and expansion amplitude, thus compensating for the drawbacks of C-VIT.

Oocyte Aging: A Multifactorial Phenomenon in A Unique Cell

The oocyte is considered to be the largest cell in mammalian species. Women hoping to become pregnant face a ticking biological clock. This is becoming increasingly challenging as an increase in life expectancy is accompanied by the tendency to conceive at older ages. With advancing maternal age, the fertilized egg will exhibit lower quality and developmental competence, which contributes to increased chances of miscarriage due to several causes such as aneuploidy, oxidative stress, epigenetics, or metabolic disorders. In particular, heterochromatin in oocytes and with it, the DNA methylation landscape undergoes changes. Further, obesity is a well-known and ever-increasing global problem as it is associated with several metabolic disorders. More importantly, both obesity and aging negatively affect female reproduction. However, among women, there is immense variability in age-related decline of oocytes' quantity, developmental competence, or quality. Herein, the relevance of obesity and DNA-methylation will be discussed as these aspects have a tremendous effect on female fertility, and it is a topic of continuous and widespread interest that has yet to be fully addressed for the mammalian oocyte.

Spatiotemporal Distribution and Function of Mitochondria in Oocytes

Mitochondria are energy provider organelles in eukaryotic cells that contain their own specific genome. This review addresses structural and functional properties of mitochondria, focusing on recent discoveries about the changes in quality and number of mitochondria per cell during oocyte development. We highlight how oocyte mitochondria exhibit stage-specific morphology and characteristics at different stages of development, in sharp contrast to the elongated mitochondria present in somatic cells. We then evaluate the latest transcriptomic data to elucidate the complex functions of mitochondria during oocyte maturation and the impact of mitochondria on oocyte development. Finally, we describe the methodological progress of mitochondrial replacement therapy to rescue oocytes with developmental disorders or mitochondrial diseases, hoping to provide a guiding reference to future clinical applications.

Prevention of moderate and severe ovarian hyperstimulation syndrome: a guideline

Ovarian hyperstimulation syndrome is a serious complication associated with assisted reproductive technology. This systematic review aims to identify who is at high risk for developing ovarian hyperstimulation syndrome, along with evidence-based strategies to prevent it and replaces the document of the same name last published in 2016.

A mutual comparison of pregnancy outcomes between different conception modes: a propensity score matching based retrospective cohort study

Background

Assisted reproductive technology (ART) has been reported to have negative effects on maternal and neonatal health. Ovulation induction (OI) was reported to be associated with alteration of epigenetic modification of mice embryos, and extinguishing the influence of ovulation induction and in vitro operations on maternal and neonatal health will bring benefits for reducing side effects. The present study aimed to determine whether ovulation induction alone and ART are associated with adverse pregnancy outcomes and whether ART could induce a higher risk than ovulation induction alone.

Methods

A total of 51,172 cases with singleton live birth between Jan 2016 and May 2019 at the International Peace Maternal and Child Health Hospital were included in this study. Conception modes documented during registration were classified into natural conception (NC), OI, and ART. Pregnancy outcomes of the three groups with balanced baseline characteristics by propensity score matching were compared. The relative risks of maternal and neonatal outcomes were calculated by logistic regression analysis.

Results

Compared with natural conception, infertility treatments are associated with gestational diabetes (OI: OR 1.72, 95% CI 1.31-2.27; ART: OR 1.67, 95% CI 1.26-2.20), preeclampsia/eclampsia (OI: OR 1.86, 95% CI 1.03-3.36; ART: OR 2.23, 95% CI 1.26-3.92). Even if gestational diabetes, gestational hypertension, and placental problems were adjusted, infertility treatments are associated with birth before 37 weeks (OI: OR 1.99, 95% CI 1.28-3.12; ART: OR 1.70, 95% CI 1.08-2.69), low birth weight (OI: OR 2.19, 95% CI 1.23-3.91; ART: OR 1.90, 95% CI 1.05-3.45), and SGA (OI: OR 2.42, 95% CI 1.20-4.87; ART: OR 2.56, 95% CI 1.28-5.11). ART but not OI is associated with a higher risk of birth before 34 weeks (OR:3.12, 95% CI 1.21-8.05). By comparing the OI group with the ART group, we only found that ART could induce a higher ratio of placental problems (5.0%, 26/518 vs 2.1%, 11/519, p<0.05).

Conclusion

Both OI and ART are associated with adverse pregnancy outcomes. ART induced comparable negative effects with OI on gestational complications, birth weight, and premature birth (<37 weeks). However, ART resulted in a higher risk of placental problems than group NC and OI. The incidence of birth before 34 weeks of gestation in the ART group tends to be higher than in the OI group, but not statistically significant. The side effects of ART may originate from OI.

Maternal High-Fat Diet Affects the Contents of Eggs and Causes Abnormal Development in the Medaka Fish

Maternal nutritional status can affect development and metabolic phenotypes of progeny in animals. The effects of maternal diet are thought to be mediated mainly by changes inside oocytes such as organelles, maternal RNAs, and metabolites. However, to what extent each factor contributes to offspring phenotypes remains uncertain, especially in viviparous mammalian systems, where factors other than oocytes, such as placenta and milk, need to be considered. Here, using the medaka fish as an oviparous vertebrate model, we examined whether maternal high-fat diet (mHFD) feeding affects offspring development and what kind of changes occur in the contents of mature eggs. We found that mHFD caused the high frequency of embryonic deformities of offspring, accompanied by downregulation of transcription- and translation-related genes and zygotic transcripts at the blastula stage. Transcriptomic and metabolomic analyses of mature eggs suggested decreased catabolism of amino acids and glycogen, moderate upregulation of endoplasmic reticulum stress-related genes, and elevated lipid levels in mHFD eggs. Furthermore, high-fat diet females showed a higher incidence of oocyte atresia and downregulation of egg protein genes in the liver. These data suggest that attenuated amino acid catabolism triggered by decreased yolk protein load/processing, as well as elevated lipid levels inside eggs, are the prime candidates that account for the higher incidence of embryonic deformities in mHFD offspring. Our study presents a comprehensive data on the changes inside eggs in a mHFD model of nonmammalian vertebrates and provides insights into the mechanisms of parental nutritional effects on offspring.

Maternal obesity induced metabolic disorders in offspring and myeloid reprogramming by epigenetic regulation

Maternal obesity and gestational diabetes are associated with childhood obesity and increased cardiovascular risk. In this review, we will discuss and summarize extensive clinical and experimental studies that metabolically imbalanced environment exposure in early life plays a critical role in influencing later susceptibility to chronic inflammatory diseases and metabolic syndrome. The effect of maternal obesity and metabolic disorders, including gestational diabetes cause Large-for-gestational-age (LGA) children to link future development of adverse health issues such as obesity, atherosclerosis, hypertension, and non-alcoholic fatty liver disease by immune reprogramming to adverse micro-environment. This review also addresses intrauterine environment-driven myeloid reprogramming by epigenetic regulations and the epigenetic markers as an underlying mechanism. This will facilitate future investigations regarding maternal-to-fetal immune regulation and the epigenetic mechanisms of obesity and cardiovascular diseases.

Influence of repeated estrus synchronization treatment on hormone secretion, growth, and development of dairy goats

In large-scale intensive farms, dairy goats often undergo frequent estrus synchronization (ES) treatment, which may result in a decline in reproductive performance; however, the underlying mechanism remains unclear. The present study aimed to investigate the effect of pregnant mare serum gonadotropin (PMSG) and progesterone (P4)-mediated ES treatment on fertility in dairy goats, while also identifying key metabolic and endocrine mechanisms that influence reproductive performance in does subjected to repeated ES treatment. Forty-eight Saanen does were randomly assigned to two groups (24 goats each) that received ES treatments either thrice fortnightly (3-PMSG) or once (1-PMSG) simultaneously with the third ES treatment of the 3-PMSG group during the breeding season. ES treatment was performed via the intravaginal insertion of a controlled internal drug release (CIDR) device impregnated with 300 mg P4, followed by 300 IU PMSG injections 48 h before CIDR withdrawal. Blood was collected to detect the level of hormones and blood biochemical indices. Additionally, estrus rate, fecundity rate, body weight, size, and lactation performance were measured. The results showed that repeated ES treatment markedly decreased the estrus rate and fecundity rate of goats. Among the does in all groups, there was no substantial difference in follicle stimulating hormone, luteinising hormone, gonadotropin-releasing hormone, melatonin, growth hormone, PMSG, total cholesterol, total protein, and glucose levels, as well as the body weight, body size, and lactation performance. Repeated ES treatment elevated estrogen (E2) levels 36, 48, and 72 h post-CIDR removal; increased P4 upon CIDR insertion; and raised PMSG antibody levels 24, 48, and 72 h post-CIDR removal. The results suggest that elevated anti-PMSG levels are the primary reason for the decline in ES efficiency, and that high E2 and P4 levels at some time points also impair reproductive performance. These findings provide novel insights into the metabolic effects of repeated PMSG stimulation in goats, guiding future reproductive hormone use in breeding practices.

Ubiquitination plays an important role during the formation of chicken primordial germ cells

As an important posttranslational modification, ubiquitination plays an important role in regulating protein homeostasis in eukaryotic cells. In our previous studies, both the transcriptome and proteome suggested that ubiquitination is involved in the formation of chicken primordial germ cells (PGCs). Here, affinity enrichment combined with liquid chromatography-tandem mass spectrometry (MS/MS) was used to analyze the ubiquitome during the differentiation from embryonic stem cells to PGCs, and we identify that 724 lysine ubiquitinated sites were up-regulated in 558 proteins and 138 lysine ubiquitinated sites were down-regulated in 109 proteins. Furthermore, GO and KEGG enrichment analysis showed that ubiquitination regulates key proteins to participate in the progression of key events related to PGC formation and the transduction of key signals such as Wnt, MAPK, and insulin signals, followed by the detailed explanation of the specific regulatory mechanism of ubiquitination through the combined proteome and ubiquitome analysis. Moreover, both the activation and inhibition of neddylation were detrimental to the maintenance of the biological characteristics of PGCs, which also verified the importance of ubiquitination. In conclusion, this study provides a global view of the ubiquitome during the formation of PGCs by label-free quantitative ubiquitomics, which lays a theoretical foundation for the formation mechanism and specific application of chicken PGCs.

Expression profiles of lncRNAs, miRNAs, and mRNAs and interaction analysis indicate their potential involvement during testicular fusion in Spodoptera litura

Testicular fusion of Spodoptera litura occures during metamorphosis, which benefits sperms development. Previous research identified involvement of ECM-integrin interaction pathways, MMPs in testicular fusion, but the regulatory mechanism remains unclear. RNA-seq was performed to analyze long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) in testes, aiming to uncover potential regulatory mechanisms of testicular fusion. 2150 lncRNAs, 2742 targeted mRNAs, and 347 miRNAs were identified in testes at three different developmental stages. Up-regulated DElncRNAs and DEmRNAs, as well as down-regulated DEmiRNAs, were observed during testicular fusion, while the opposite expression pattern was observed after fusion. Enrichment analysis of DEmRNAs revealed that cAMP signal pathway, ECM remodeling enzymes, ECM-integrin interaction pathways, and cell adhesion molecules were potentially associated with testicular fusion. The identified DElncRNA-DEmiRNA-DEmRNA regulatory network related to cAMP signal pathway, ECM remodeling enzymes suggests their roles during testicular fusion. Our research will provide new targets for studying the mechanism of testicular fusion.

A clinical approach to diagnosis and management of mitochondrial myopathies

This paper provides an overview of the different types of mitochondrial myopathies (MM), associated phenotypes, genotypes as well as a practical clinical approach towards disease diagnosis, surveillance, and management. nDNA-related MM are more common in pediatric-onset disease whilst mtDNA-related MMs are more frequent in adults. Genotype-phenotype correlation in MM is challenging due to clinical and genetic heterogeneity. The multisystemic nature of many MMs adds to the diagnostic challenge. Diagnostic approaches utilizing genetic sequencing with next generation sequencing approaches such as gene panel, exome and genome sequencing are available. This aids molecular diagnosis, heteroplasmy detection in MM patients and furthers knowledge of known mitochondrial genes. Precise disease diagnosis can end the diagnostic odyssey for patients, avoid unnecessary testing, provide prognosis, facilitate anticipatory management, and enable access to available therapies or clinical trials. Adjunctive tests such as functional and exercise testing could aid surveillance of MM patients. Management requires a multi-disciplinary approach, systemic screening for comorbidities, cofactor supplementation, avoidance of substances that inhibit the respiratory chain and exercise training. This update of the current understanding on MMs provides practical perspectives on current diagnostic and management approaches for this complex group of disorders.

The contribution of age-related changes in the gut-brain axis to neurological disorders

Trillions of microbes live symbiotically in the host, specifically in mucosal tissues such as the gut. Recent advances in metagenomics and metabolomics have revealed that the gut microbiota plays a critical role in the regulation of host immunity and metabolism, communicating through bidirectional interactions in the microbiota-gut-brain axis (MGBA). The gut microbiota regulates both gut and systemic immunity and contributes to the neurodevelopment and behaviors of the host. With aging, the composition of the microbiota changes, and emerging studies have linked these shifts in microbial populations to age-related neurological diseases (NDs). Preclinical studies have demonstrated that gut microbiota-targeted therapies can improve behavioral outcomes in the host by modulating microbial, metabolomic, and immunological profiles. In this review, we discuss the pathways of brain-to-gut or gut-to-brain signaling and summarize the role of gut microbiota and microbial metabolites across the lifespan and in disease. We highlight recent studies investigating 1) microbial changes with aging; 2) how aging of the maternal microbiome can affect offspring health; and 3) the contribution of the microbiome to both chronic age-related diseases (e.g., Parkinson's disease, Alzheimer's disease and cerebral amyloidosis), and acute brain injury, including ischemic stroke and traumatic brain injury.

The Impact of Centrosome Pathologies on Ovarian Cancer Development and Progression with a Focus on Centrosomes as Therapeutic Target

The impact of centrosome abnormalities on cancer cell proliferation has been recognized as early as 1914 (Boveri, Zur Frage der Entstehung maligner Tumoren. Jena: G. Fisher, 1914), but vigorous research on molecular levels has only recently started when it became fully apparent that centrosomes can be targeted for new cancer therapies. While best known for their microtubule-organizing capabilities as MTOC (microtubule organizing center) in interphase and mitosis, centrosomes are now further well known for a variety of different functions, some of which are related to microtubule organization and consequential activities such as cell division, migration, maintenance of cell shape, and vesicle transport powered by motor proteins, while other functions include essential roles in cell cycle regulation, metabolic activities, signal transduction, proteolytic activity, and several others that are now heavily being investigated for their role in diseases and disorders (reviewed in Schatten and Sun, Histochem Cell Biol 150:303-325, 2018; Schatten, Adv Anat Embryol Cell Biol 235:43-50, 2022a; Schatten, Adv Anat Embryol Cell Biol 235:17-35, 2022b).Cancer cell centrosomes differ from centrosomes in noncancer cells in displaying specific abnormalities that include phosphorylation abnormalities, overexpression of specific centrosomal proteins, abnormalities in centriole and centrosome duplication, formation of multipolar spindles that play a role in aneuploidy and genomic instability, and several others that are highlighted in the present review on ovarian cancer. Ovarian cancer cell centrosomes, like those in other cancers, display complex abnormalities that in part are based on the heterogeneity of cells in the cancer tissues resulting from different etiologies of individual cancer cells that will be discussed in more detail in this chapter.Because of the critical role of centrosomes in cancer cell proliferation, several lines of research are being pursued to target centrosomes for therapeutic intervention to inhibit abnormal cancer cell proliferation and control tumor progression. Specific centrosome abnormalities observed in ovarian cancer will be addressed in this chapter with a focus on targeting such aberrations for ovarian cancer-specific therapies.

How Do Environmental Toxicants Affect Oocyte Maturation Via Oxidative Stress?

In mammals, oogenesis initiates before birth and pauses at the dictyate stage of meiotic prophase I until luteinizing hormone (LH) surges to resume meiosis. Oocyte maturation refers to the resumption of meiosis that directs oocytes to advance from prophase I to metaphase II of meiosis. This process is carefully modulated to ensure a normal ovulation and successful fertilization. By generating excessive amounts of oxidative stress, environmental toxicants can disrupt the oocyte maturation. In this review, we categorized these environmental toxicants that induce mitochondrial dysfunction and abnormal spindle formation. Further, we discussed the underlying mechanisms that hinder oocyte maturation, including mitochondrial function, spindle formation, and DNA damage response.

ROCK1 is a multifunctional factor maintaining the primordial follicle reserve and follicular development in mice

The follicle is the basic structural and functional unit of the ovary in female mammals. The excessive depletion of follicles will lead to diminished ovarian reserve or even premature ovarian failure, resulting in diminished ovarian oogenesis and endocrine function. Excessive follicular depletion is mainly due to loss of primordial follicles. Our analysis of published human ovarian single-cell sequencing results by others revealed a significant increase in rho-associated protein kinase 1 (ROCK1) expression during primordial follicle development. However, the role of ROCK1 in primordial follicle development and maintenance is not clear. This study revealed a gradual increase in ROCK1 expression during primordial follicle activation. Inhibition of ROCK1 resulted in reduced primordial follicle activation, decreased follicular reserve, and delayed development of growing follicles. This effect may be achieved through the HIPPO pathway. The present study indicates that ROCK1 is a key molecule for primordial follicular reserve and follicular development.NEW & NOTEWORTHY ROCK1, one of the Rho GTPases, plays an important role in primordial follicle reserve and follicular development. ROCK1 was primarily expressed in the cytoplasm of oocytes and granulosa cell in mice. Inhibition of ROCK1 significantly reduced the primordial follicle reserve and delayed growing follicle development. ROCK1 regulates primordial follicular reserve and follicle development through the HIPPO signaling pathway. These findings shed new lights on the physiology of sustaining female reproduction.

Adverse effects of microplastics and nanoplastics on the reproductive system: A comprehensive review of fertility and potential harmful interactions

In recent years, microplastics (MPs) and nanoplastics (NPs) have caused ubiquitous environmental pollution and raised widespread concern about their potential toxicity to human health, especially in the reproductive system. Moreover, infertility affects >15 % of couples worldwide, and the birth rate is decreasing. Environmental factors are some of the most important causes of infertility. However, little is known about the effects of MPs and NPs on the testes and ovaries. These particles can enter the body primarily via ingestion, inhalation, and skin contact, target the reproductive system in a size-dependent manner and disturb germ cell and other somatic cell development. Our study systematically reviewed the adverse effects of plastic particles on reproductive function and offers valuable insights into the different stages of germ cells and the potential mechanisms. Moreover, the synergistic reproductive toxicity of these particles and carried contaminants was summarized. Given the limited research scale, a shift toward innovative technologies and the adoption of multiple omics are recommended for advancing related studies. Further study is needed to explore the reproductive toxicity of MPs and NPs based on their size, polymer type, shape, and carried toxins, establish effective protective measures, and develop precision medicine for targeted reproductive damage.