Progesterone affects clinic oocyte yields by coordinating with follicle stimulating hormone via PI3K/AKT and MAPK pathways

Luteinizing Hormone Receptor Mutation (LHRN316S) Causes Abnormal Follicular Development Revealed by Follicle Single-Cell Analysis and CRISPR/Cas9

Abnormal interaction between granulosa cells and oocytes causes disordered development of ovarian follicles. However, the interactions between oocytes and cumulus granulosa cells (CGs), oocytes and mural granulosa cells (MGs), and CGs and MGs remain to be fully explored. Using single-cell RNA-sequencing (scRNA-seq), we determined the transcriptional profiles of oocytes, CGs and MGs in antral follicles. Analysis of scRNA-seq data revealed that CGs may regulate follicular development through the BMP15-KITL-KIT-PI3K-ARF6 pathway with elevated expression of luteinizing hormone receptor (LHR). Because internalization of the LHR is regulated by Arf6, we constructed LHRN316S mice by CRISPR/Cas9 to further explore mechanisms of follicular development and novel treatment strategies for female infertility. Ovaries of LHRN316S mice exhibited reduced numbers of corpora lutea and ovulation. The LHRN316S mice had a reduced rate of oocyte maturation in vitro and decreased serum progesterone levels. Mating LHRN316S female mice with ICR wild type male mice revealed that the infertility rate of LHRN316S mice was 21.4% (3/14). Litter sizes from LHRN316S mice were smaller than those from control wild type female mice. The oocytes from LHRN316S mice had an increased rate of maturation in vitro after progesterone administration in vitro. Furthermore, progesterone treated LHRN316S mice produced offspring numbers per litter equivalent to WT mice. These findings provide key insights into cellular interactions in ovarian follicles and provide important clues for infertility treatment.

Thyroid transcriptomic profiling reveals the differential regulation of lncRNA and mRNA related to prolificacy in small tail han sheep with FecB BB genotype

BACKGROUND

The thyroid gland is an important endocrine gland in animals that secretes thyroid hormones and acts on various organs throughout the body. lncRNAs are long non-coding RNAs that play an important role in animal reproduction; however, there is a lack of understanding of their expression patterns and potential roles in the thyroid gland of the Small Tail Han (STH) sheep. In this study, we used RNA-Seq technology to examine the transcriptome expression pattern of the thyroid from the luteal phase (LP) and follicular phase (FP) of FecB BB (MM) STH sheep.

RESULTS

We identified a total of 122 and 1287 differential expression lncRNAs (DELs) and differential expression mRNAs (DEGs), respectively, which were significantly differentially expressed. These DELs target genes and DEGs can be enriched in several signalling pathways related to the animal reproduction process.

CONCLUSIONS

The expression profiles of DELs and DEGs in thyroid glands provide a more comprehensive resource for elucidating the reproductive regulatory mechanisms of STH sheep.

Single-cell RNA sequencing revealed the roles of macromolecule epidermal growth factor receptor (EGFR) in the hybrid sterility of hermaphroditic Argopecten scallops

The macromolecule epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein that belongs to the protein kinase superfamily, which plays versatile functions in cell proliferation, development and fertility regulation. Almost all F1 hybrids obtained from the hermaphroditic bay scallops and Peruvian scallops exhibit infertility, and the genetic mechanism remains unclear. In this study, the comprehensive scRNA-seq was first conducted in the gonads of hybrid scallops, deducing the developmental sequence of germ cells and identifying the critical regulators in hybrid sterility: epidermal growth factor receptor. During the development from oogenesis phase germ cells to oocytes, the expression of the EGFR gene gradually decreased in sterile hybrids but increased in fertile hybrids. The significantly lower EGFR expression and ATP content, but higher ROS production rate was detected in the gonad of sterile hybrids than that in fertile hybrids, which might cause slow development of oocytes, stagnation of cell cycle, insufficient energy supply, high level of apoptosis and final sterility. Specific knock-down of EGFR gene led to decreased ATP content, increased ROS production rate, and inhibited oocyte maturation and gonadal development. These findings provide new insights into the roles of EGFR in hybrid infertility of bivalves and the healthy development of scallop breeding.

The usefulness of peri-trigger female reproductive hormones (delta-FRH) in predicting oocyte maturation in normal ovarian reserve patients who received in vitro fertilization-embryo transfer: a retrospective study

Objectives

To evaluate the efficacy of peri-trigger female reproductive hormones (FRHs) in the prediction of oocyte maturation in normal ovarian reserve patients during the in vitro fertilization-embryo transfer (IVF-ET) procedure.

Materials and Methods

A hospital database was used to extract data on IVF-ET cases from January 2020 to September 2021. The levels of female reproductive hormones, including estradiol (E2), luteinizing hormone (LH), progesterone (P), and follicle-stimulating hormone (FSH), were initially evaluated at baseline, the day of the trigger, the day after the trigger, and the day of oocyte retrieval. The relative change in E2, LH, P, FSH between time point 1 (the day of trigger and baseline) and time point 2 (the day after the trigger and day on the trigger) was defined as E2_RoV1/2, LH_RoV1/2, P_RoV1/2, and FSH_RoV1/2, respectively. Univariable and multivariable regression were performed to screen the peri-trigger FRHs for the prediction of oocyte maturation.

Results

A total of 118 patients were enrolled in our study. Univariable analysis revealed significant associations between E2_RoV1 and the rate of MII oocytes in the GnRH-agonist protocol group (p < 0.05), but not in the GnRH-antagonist protocol group. Conversely, P_RoV2 emerged as a potential predictor for the rate of MII oocytes in both protocol groups (p < 0.05). Multivariable analysis confirmed the significance of P_RoV2 in predicting oocyte maturation rate in both groups (p < 0.05), while the association of E2_RoV1 was not significant in either group. However, within the subgroup of high P_RoV2 in the GnRH-agonist protocol group, association was not observed to be significant. The C-index was 0.83 (95% CI [0.73-0.92]) for the GnRH-agonist protocol group and 0.77 (95% CI [0.63-0.90]) for the GnRH-antagonist protocol group. The ROC curve analysis further supported the satisfactory performance of the models, with area under the curve (AUC) values of 0.79 for the GnRH-agonist protocol group and 0.81 for the GnRH-antagonist protocol group.

Conclusions

P_RoV2 showed significant predictive value for oocyte maturation in both GnRH-agonist and GnRH-antagonist protocol groups, which enhances the understanding of evaluating oocyte maturation and inform individualized treatment protocols in controlled ovarian hyperstimulation during IVF-ET for normal ovarian reserve patients.

Uncovering the genetic diversity and adaptability of Butuo Black Sheep through whole-genome re-sequencing

The Butuo Black Sheep (BBS) is well-known for its ability to thrive at high altitudes, resist diseases, and produce premium-quality meat. Nonetheless, there is insufficient data regarding its genetic diversity and population-specific Single nucleotide polymorphisms (SNPs). This paper centers on the genetic diversity of (BBS). The investigation conducted a whole-genome resequencing of 33 BBS individuals to recognize distinct SNPs exclusive to BBS. The inquiry utilized bioinformatic analysis to identify and explain SNPs and pinpoint crucial mutation sites. The findings reveal that reproductive-related genes (GHR, FSHR, PGR, BMPR1B, FST, ESR1), lipid-related genes (PPARGC1A, STAT6, DGAT1, ACACA, LPL), and protein-related genes (CSN2, LALBA, CSN1S1, CSN1S2) were identified as hub genes. Functional enrichment analysis showed that genes associated with reproduction, immunity, inflammation, hypoxia, PI3K-Akt, and AMPK signaling pathways were present. This research suggests that the unique ability of BBS to adapt to low oxygen levels in the plateau environment may be owing to mutations in a variety of genes. This study provides valuable insights into the genetic makeup of BBS and its potential implications for breeding and conservation efforts. The genes and SPNs identified in this study could serve as molecular markers for BBS.

Methylosome protein 50 is necessary for oogenesis in medaka

Methylosome protein 50 (Mep50) functions as a partner to protein arginine methyltransferase 5. MEP50 serves as a coactivator for both the androgen receptor and estrogen receptor in humans. Mep50 plays a crucial role in the development of germ cells in Drosophila. The precise role of Mep50 in oogenesis remains unclear in vertebrates. The objective of this study was to investigate the role of Mep50 in oogenesis in medaka fish. Disruption of Mep50 resulted in impaired oogenesis and the formation of multiple oocyte follicles in medaka. RNA-seq analysis revealed significant differential gene expression in the mutant ovary, with 4542 genes up-regulated and 1264 genes down-regulated. The regulated genes were found to be enriched in cellular matrices and ECM-receptor interaction, the Notch signaling pathway, the PI3K-Akt signaling pathway, the MAPK signaling pathway, the Hippo signaling pathway, and the Jak-Stat pathway, among others. In addition, the genes related to the hypothalamus-pituitary-gonad axis, steroid metabolism, and IGF system were impacted. Furthermore, the mutation of mep50 caused significant alterations in alternative splicing of pre-mRNA in ovarian cells. Quantitative RT-PCR results validated the findings from RNA-seq analysis in the specific genes, including akt2, map3k5, yap1, fshr, cyp17a, igf1, ythdc2, cdk6, and col1, among others. The findings of this study demonstrate that Mep50 plays a crucial role in oogenesis, participating in a diverse range of biological processes such as steroid metabolism, cell matrix regulation, and signal pathways. This may be achieved through the regulation of gene expression via mRNA splicing in medaka ovarian cells.

GnRH-mediated suppression of S100A4 expression inhibits endometrial epithelial cell proliferation in sheep via GNAI2/MAPK signaling

Background

Gonadotrophin-releasing hormone (GnRH) administration significantly decreases the pregnancy rate of recipient ewes after embryo transfer, possibly because GnRH affects endometrial epithelial cell function. Therefore, this study investigated the effect of GnRH on endometrial epithelial cells.

Methods

Transcriptome sequencing was used to determine the regulatory effect of GnRH on the ewe endometrium, and the S100A4 gene, which showed altered transcription, was screened as a candidate regulator of this effect. Endometrial epithelial cells were further isolated, the S100A4 protein was immunoprecipitated, and host proteins that interacted with S100A4 were identified by mass spectrometry. We further verified the effects of S100A4 and GNAI2 on the proliferation of endometrial epithelial cells via overexpression/knockdown experiments and subsequent CCK-8 and EdU assays. The effect of S100A4 deletion in endometrial cells on reproduction was verified in mice with S100A4 knockout.

Results

Our results showed that S100A4 gene transcription in endometrial cells was significantly inhibited after GnRH administration. GNAI2 was identified as a downstream interacting protein of S100A4, and S100A4 was confirmed to activate the MAPK signaling pathway to promote cell proliferation by targeting GNAI2.

Conclusion

GnRH can suppress the expression of S100A4 in the endometrium, consequently inhibiting the proliferation of endometrial cells through the S100A4/GNAI2/MAPK signaling pathway. These findings suggest a potential explanation for the limited efficacy of GnRH in promoting embryo implantation.

Non-inferiority of progestin-primed ovarian stimulation versus GnRH antagonist protocol: A propensity score-weighted analysis

PURPOSE

To evaluate the effectiveness of the progestin-primed ovarian stimulation (PPOS) protocol versus the gonadotropin-releasing hormone antagonist (GnRH-ant) protocol in ovarian stimulation.

METHODS

In this retrospective cohort study, we included 804 patients who were treated between January 1st, 2022, and July 1st, 2023. Outcomes of ovarian stimulation were compared between the PPOS (n = 206) and GnRH-ant (n = 598). The primary outcome was the number of good cleavage embryos.

RESULTS

Baseline characteristics were comparable in both groups. In both unadjusted and adjusted analysis, the mean number of good cleavage embryos in PPOS (6.33) was non-inferior to GnRH-ant (6.44; unadjusted ratio of two means 1.02, 95%CI 0.92, 1.13). The trigger-day estradiol level in patients with PPOS was higher than in patients with GnRH-ant (4,420 vs 3,830 pg/ml, respectively) despite similar total follicle stimulating hormone dose and fewer days of ovarian stimulation. The number of oocytes, MII oocytes, cleavage and blastocyst embryos were comparable between the two protocols. After the first transfer of embryos, the clinical pregnancy rate and implantation rate were higher in the PPOS group, while the pregnancy rate and ongoing pregnancy were not significantly different. None of the PPOS patients had an unexpected LH surge, and serum LH levels decreased slightly during ovarian stimulation.

CONCLUSIONS

The PPOS protocol with dydrogesterone provided similar embryo outcomes to the GnRH-ant protocol, with notable distinctions in clinical pregnancy and implantation rate. The serum LH concentration during ovarian stimulation using PPOS was well-controlled.

Whole-Genome Re-sequencing and Transcriptome Reveal Candidate Genes and Pathways Associated with Hybrid Sterility in Hermaphroditic Argopecten Scallops

The interspecific hybrid scallops generated from the hermaphroditic bay scallops (Argopecten irradians) and Peruvian scallops (Argopecten purpuratus) showed significant heterosis in growth. However, its sterility limits large-scale hybridization and hinders the development of the scallop breeding industry. Hybrid sterility is regulated by plenty of genes and involves a range of biochemical and physiological transformations. In this study, whole-genome re-sequencing and transcriptomic analysis were performed in sterile and fertile hybrid scallops. The potential genetic variations and abnormally expressed genes were detected to explore the mechanism underlying hybrid sterility in hermaphroditic Argopecten scallops. Compared with fertile hybrids, 24 differentially expressed genes (DEGs) with 246 variations were identified to be related to fertility regulation, which were mainly enriched in germarium-derived egg chamber formation, spermatogenesis, spermatid development, mismatch repair, mitotic and meiotic cell cycles, Wnt signaling pathway, MAPK signaling pathway, calcium modulating pathway, and notch signaling pathway. Specifically, variation and abnormal expression of these genes might inhibit the progress of mitosis and meiosis, promote cell apoptosis, and impede the genesis and maturation of gametes in sterile hybrid scallops. Eleven DEGs (XIAP, KAZN, CDC42, MEIS1, SETD1B, NOTCH2, TRPV5, M- EXO1, GGT1, SBDS, and TBCEL) were confirmed by qRT-PCR validation. Our findings may enrich the determination mechanism of hybrid sterility and provide new insights into the use of interspecific hybrids for extensive breeding.

A delayed ovulation of progestin-primed ovarian stimulation (PPOS) by downregulating the LHCGR/PGR pathway

Progestin-primed ovarian stimulation (PPOS) is a new ovulation stimulation protocol, and its role in ovulation and regulatory mechanism is unclear. The clinical PPOS protocol was simulated in mice. The ovulated oocytes, estradiol, progesterone, and luteinizing hormone (LH) levels were analyzed at different hours after trigger. mRNA extraction and real-time PCR, hematoxylin and eosin staining, and immunofluorescence of ovaries were used to explore the involved signaling pathways. The PPOS group had a delayed ovulation at 12.5 h after trigger. Its suppressed LH level reduced the expression of luteinizing hormone/choriogonadotropin receptor (LHCGR) on the preovulatory follicles before trigger and significantly decreased the following progesterone synthesis, blood progesterone level, and progesterone receptor (PGR) expression within 4-6 h after trigger. Furthermore, the important ovulatory genes regulated by PGR including ADAMTS-1, VEGF-A, and EDN2 were downregulated, ultimately delaying the ovulation. PPOS suppresses the LH level before trigger and decreases the synthesis of progesterone after trigger, thus delaying the ovulation by downregulating the LHCGR-PGR pathway.

Decreased growth differentiation factor 9, bone morphogenetic protein 15, and forkhead box O3a expressions in the ovary via ulipristal acetate

OBJECTIVE

Folliculogenesis is a complex process involving various ovarian paracrine factors. During folliculogenesis, vitamin D3 and progesterone are significant for the proper development of follicles. This study aimed to investigate the effects of vitamin D3 and selective progesterone receptor modulator ulipristal acetate on ovarian paracrine factors.

METHODS

In the study, 18 female Wistar-albino rats were randomly divided into three groups: control group (saline administration, n=6), vitamin D3 group (300 ng/day vitamin D3 oral administration, n=6), and UPA group (3 mg/kg/day ulipristal acetate oral administration, n=6). Ovarian tissue was analyzed by histochemistry and immunohistochemistry. For quantification of immunohistochemistry, the mean intensities of growth differentiation factor 9, bone morphogenetic protein 15, and forkhead box O3a expressions were measured by Image J and MATLAB. Blood samples were collected for the analysis of serum anti-Müllerian hormone levels by ELISA.

RESULTS

Atretic follicles and hemorrhagic cystic structures were observed in the UPA group. After immunohistochemistry via folliculogenesis assessment markers, growth differentiation factor 9, bone morphogenetic protein 15, and cytoplasmic forkhead box O3a expressions decreased in the UPA group (p<0.05). Anti-Müllerian hormone level did not differ significantly between the experimental groups (p>0.05).

CONCLUSION

Ulipristal acetate negatively affects folliculogenesis via ovarian paracrine factors. The recommended dietary vitamin D3 supplementation in healthy cases did not cause a significant change.

Multi-omics reveal the metabolic patterns in mouse cumulus cells during oocyte maturation

Bi-directional communication between cumulus cells and the surrounded oocytes is important for the development and functions of both compartments. However, the metabolic framework in cumulus cells has not been systematically described. In the present study, cumulus cells from cumulus-oocyte complexes (COCs) at three key time points were isolated (arrested GV stage, post-hCG 0h; meiotic resumption GVBD stage, post-hCG 3h; and metaphase II stage, post-hCG 12h), and the temporal metabolomic and proteomic profiling were performed. Integrated multi-omics analysis reveals the global metabolic patterns in cumulus cells during mouse oocyte maturation. In particular, we found the active hyaluronic acid metabolism, steroid hormone synthesis, and prostaglandin E2 (PGE2) production in cumulus cells. Meanwhile, accompanying the oocyte maturation, a progressive increase in nucleotide and amino acid metabolism was detected in the surrounding cumulus cells. In sum, the data serve as a valuable resource for probing metabolism during terminal differentiation of ovarian granulosa cells, and provide the potential biomarkers for improving and predicting oocyte quality.

Progestin Primed Ovarian Stimulation (PPOS) protocol yields lower euploidy rate in older patients undergoing IVF

BACKGROUND

To explore if exogenous progestin required for progestin primed ovarian stimulation (PPOS) protocol compromises the euploidy rate of patients who underwent preimplantation genetic testing cycles when compared to those who received the conventional gonadotropin-releasing hormone (GnRH) antagonist protocol.

METHODS

This retrospective cohort study analyzed 128 preimplantation genetic testing for aneuploidy (PGT-A) cycles performed from January 2018 to December 2021 in a single university hospital-affiliated fertility center. Infertile women aged 27 to 45 years old requiring PGT-A underwent either PPOS protocol or GnRH-antagonist protocol with in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) for fertilization. Frozen embryo transfers were performed following each PGT-A cycle. Data regarding the two groups were analyzed using the Statistical Package for Social Sciences (SPSS) version 22.0 (SPSS Inc., Chicago, IL).

RESULTS

Patients who underwent PPOS treatment had significantly reduced blastocyst formation rate and euploidy rate compared to those who received the GnRH antagonist protocol. Subgroup-analysis was performed by stratifying patients' age into elder and young subgroups (elder: ≥ 38-year-old, young: < 38-year-old). In the elder sub-population, the blastocyst formation rate of the PPOS group was significantly lower than that of the GnRH-antagonist group (45.8 ± 6.1% vs. 59.9 ± 3.8%, p = 0.036). Moreover, the euploidy rate of the PPOS group was only about 20% of that of  the GnRH-antagonist group (5.4% and 26.7%, p = 0.006). In contrast, no significant differences in blastocyst formation rate (63.5 ± 5.7% vs. 67.1 ± 3.2%, p = 0.45) or euploidy rate (30.1% vs. 38.5%, p = 0.221) were observed in the young sub-population. Secondary outcomes, which included implantation rate, biochemical pregnancy rate, clinical pregnancy rate, live birth rate, and miscarriage rate, were comparable between the two treatment groups, regardless of age.

CONCLUSION

When compared to the conventional GnRH-antagonist approach, PPOS protocol could potentially reduce the euploidy rate in aging IVF patients. However, due to the retrospective nature of this study, the results are to be interpreted with caution. Before the PPOS protocol is widely implemented, further studies exploring its efficacy in larger populations are needed to define the optimal patient selection suitable for this method.

TRIAL REGISTRATION

Human Investigation and Ethical Committee of Chang Gung Medical Foundation (202200194B0).

Dynamic Changes in Proteome during Yak Oocyte Maturation Analyzed Using iTRAQ Technology

The aim of this study was to investigate protein regulation at different time points during the in vitro maturation of yak oocytes. Yak oocytes at GV, MI, and MII stages were collected during in vitro maturation, and differential proteomics sequencing was performed using iTRAQ technology. GO functional classification indicated that the differential proteins were closely associated with biological processes such as "metabolic processes", and molecular events such as "binding" molecular-function-related categories were active. KOG analysis showed that energy-metabolism-related activities were vigorous during oocyte development from the GV phase to MI phase, and genetic material preparation activities were more active when oocytes developed from the MI stage to MII stage. KEGG pathway analysis showed that the PPAR metabolic pathway, Hippo signaling pathway, and ECM-receptor interaction and metabolic pathway were enriched from the GV to the MI stages. The PI3K-Akt, TGF-β, and phagosome pathways were enriched from the MI stage to the MII stage. These results indicate that transient dynamic changes occurred in the proteome during the maturation of yak oocytes, and the physiological functions mediated by these were also different. The accurate identification of the differential proteins in the three stages of GV, MI, and MII was helpful in further analyzing the molecular regulatory mechanism of yak oocyte maturation.

RNA Transcripts in Human Ovarian Cells: Two-Time Cryopreservation Does Not Affect Developmental Potential

Sometimes, for medical reasons, when a frozen tissue has already thawed, an operation by re-transplantation may be cancelled, and ovarian tissues should be re-frozen for transplantation next time. Research about the repeated cryopreservation of ovarian cells is rarely reported. It has been published that there is no difference in the follicle densities, proportions of proliferation of early preantral follicles, appearance of atretic follicles, or ultrastructural quality of frozen-thawed and re-frozen-rethawed tissue. However, the molecular mechanisms of a repeated cryopreservation effect on the developmental potential of ovarian cells are unknown. The aim of our experiments was to investigate the effect of re-freezing and re-thawing ovarian tissue on gene expression, gene function annotation, and protein-protein interactions. The morphological and biological activity of primordial, primary, and secondary follicles, aimed at using these follicles for the formation of artificial ovaries, was also detected. Second-generation mRNA sequencing technology with a high throughput and accuracy was adopted to determine the different transcriptome profiles in the cells of four groups: one-time cryopreserved (frozen and thawed) cells (Group 1), two-time cryopreserved (re-frozen and re-thawed after first cryopreservation) cells (Group 2), one-time cryopreserved (frozen and thawed) and in vitro cultured cells (Group 3), and two times cryopreserved (re-frozen and re-thawed after first cryopreservation) and in vitro cultured cells (Group 4). Some minor changes in the primordial, primary, and secondary follicles in terms of the morphology and biological activity were detected, and finally, the availability of these follicles for the formation of artificial ovaries was explored. It was established that during cryopreservation, the CEBPB/CYP19A1 pathway may be involved in regulating estrogen activity and CD44 is crucial for the development of ovarian cells. An analysis of gene expression in cryopreserved ovarian cells indicates that two-time (repeated) cryopreservation does not significantly affect the developmental potential of these cells. For medical reasons, when ovarian tissue is thawed but cannot be transplanted, it can be immediately re-frozen again.

Proteomic Differences Between the Ovulatory and Anovulatory Sides of the Mare's Follicular and Oviduct Fluid

The follicular fluid and oviduct fluid play major roles in oocyte maturation, sperm activation, and fertilization. To better understand the physiological environments for equine oocyte maturation and fertilization, here we conducted the proteome analysis and comparison on follicular fluids and oviduct fluids from the ovulatory side and the anovulatory side. The results showed that there is no significant difference between two side oviduct fluids, but a total of 71 differential abundance proteins (DAPs) were identified between two side follicular fluids, of which 9 are up-regulated and 62 are down-regulated in ovulatory side follicle fluid versus anovulatory side follicle fluid. As we expected, the function classification and enrichment results indicate that up- and down-regulated proteins are largely related to oocyte meiosis, maturation and ovulation. Noticeably, among 9 up-regulated DAPs in ovulatory side follicle fluid, as the DAP with the greatest fold change, PLA2G1B may be a newly discovered component that influences the efficacy of horse IVM/IVF. The current findings add to our knowledge of the in vivo conditions and regulation of equine reproduction, as well as the regulatory mechanism underpinning alternative ovulation.

Preventing Growth Stagnation and Premature LH Surge Are the Keys to Obtaining a Viable Embryo in Monofollicular IVF Cycles: A Retrospective Cohort Study

How LH levels influenced the outcomes of monofollicular IVF cycles using different stimulation protocols was controversial. In this single-center, retrospective study, we analyzed 815 monofollicular IVF cycles between 2016−2022 using natural cycle (NC), medroxyprogesterone acetate (MPA) or clomiphene citrate (CC) in addition to human menopausal gonadotropin (hMG), with or without GnRH antagonist. A viable embryo was obtained in 35.7% of all cycles. Growth stagnation and premature LH surge are two markedly negative factors for obtaining viable embryos (odds ratios of 0.12 [0.08−0.65], p < 0.0001 and 0.33 [0.26,0.42], p < 0.0001, respectively). NC/hMG cycles are prone to premature LH surge (40.4%), yielding a significantly lower opportunity of obtaining embryos (24.7%, p = 0.029). The administration of GnRH antagonist on the background of MPA resulted in a significant decrease in LH levels (from 2.26 IU/L to −0.89 IU/L relative to baseline, p = 0.000214), leading to a higher risk of growth stagnation (18.6%, p = 0.007). We hypothesized that the abrupt decline of LH might increase the risk of apoptosis in granulosa cells. We proposed a “marginal effect” framework to emphasize that the change of LH was the key to its bioactivity, rather than the traditional “window” concept with fixed cutoff values of a threshold and a ceiling.

Fetal programming: in utero exposure to acrylamide leads to intergenerational disrupted ovarian function and accelerated ovarian aging

In this study we investigated the effects of multigenerational exposures to acrylamide (ACR) on ovarian function. Fifty-day-old Wistar albino female rats were divided into the control and ACR-treated groups (2.5, 10, and 20 mg/kg/day) from day 6 of pregnancy until delivery. The obtained females of the first (AF1) and second generation (AF2) were euthanized at 4 weeks of age, and plasma and ovary samples were collected. We found that in utero multigenerational exposure to ACR reduced fertility and ovarian function in AF1 through inducing histopathological changes as evidenced by the appearance of cysts and degenerating follicles, oocyte vacuolization, and pyknosis in granulosa cells. TMR red positive cells confirmed by TUNEL assay were mostly detected in the stroma of the treated groups. Estradiol and IGF-1 concentrations significantly decreased as a result of decreased CYP19 gene and its protein expression. However, ACR exposure in AF2 led to early ovarian aging as evidenced by high estradiol and progesterone levels among all treated groups compared to control group, corresponding to the upregulation of the CYP19 gene and protein expression. The apoptotic cells of the stroma were greatly detected compared to that in the control group, whereas no significant difference was reported in ESR1 and ESR2 gene expression. This study confirms the developmental adverse effects of ACR on ovarian function and fertility in at least two consecutive generations. It emphasizes the need for more effective strategies during pregnancy, such as eating healthy foods and avoiding consumption of ACR-rich products, including fried foods and coffee.

Researching the Phenomenon of Poor Ovarian Responders and Management Strategies in IVF: A Narrative Review

This narrative review aims to summarize all the latest studies published between 2015-2021 concerning the management protocols adopted for poor ovarian response (POR) cases. Patients defined as "poor responders" show minimal response to controlled ovarian hyperstimulation, although there is no standard definition for POR. Although infertility specialists are endeavoring to improve cycle outcomes in poor responders by adopting multiple management strategies, still the estimated risk of cycle cancellation is about 20%. All the studies performed during this study period were evaluated and their results were recorded. The latest published protocols to improve oocyte retrieval in poor responders include: anti-Mϋllerian hormone, clomiphene citrate, co-enzyme Q10, corifollitropin, dehydroepiandrosterone, double stimulation, Follicle Stimulation Hormone, Growth Hormone, Gonadotropin-releasing hormone agonists, letrozole, human chorionic gonadotropin, Luteinizing Hormone, progesterone and testosterone. CONCLUSION: Although many strategies have been suggested to manage POR, none has been proven superior to the others. Further large-scale randomized studies are needed to validate experimental techniques leading towards successful individualized treatment regimens.

Protective Effect of Follicle-Stimulating Hormone on DNA Damage of Chicken Follicular Granulosa Cells by Inhibiting CHK2/p53

The increase in follicular atresia and the decrease in the fecundity of laying hens occur with the aging process. Therefore, the key measure for maintaining high laying performance is to alleviate follicular atresia in the aging poultry. Follicle-stimulating hormone (FSH), as an important pituitary hormone to promote follicle development and maturation, plays an important role in preventing reproductive aging in diverse animals. In this study, the physiological state of the prehierarchical small white follicles (SWFs) and atretic SWFs (ASWFs) were compared, followed by an exploration of the possible capacity of FSH to delay ASWFs' progression in the hens. The results showed that the DNA damage within follicles increased with aging, along with Golgi complex disintegration, cell cycle arrest, increased apoptosis and autophagy in the ASWFs. Subsequently, the ACNU-induced follicular atresia model was established to evaluate the enhancing capacity of FSH on increasing cell proliferation and attenuating apoptosis in ASWFs. FSH inhibited DNA damage and promoted DNA repair by regulating the CHK2/p53 pathway. Furthermore, FSH inhibited CHK2/p53, thus, suppressing the disintegration of the Golgi complex, cell cycle arrest, and increased autophagy in the atretic follicles. Moreover, these effects from FSH treatment in ACNU-induced granulosa cells were similar to the treatment by a DNA repair agent AV-153. These results indicate that FSH protects aging-resulted DNA damage in granulosa cells by inhibiting CHK2/p53 in chicken prehierarchical follicles.