Mature Follicles Research Articles

Dynamic maternal synthesis and segregation of the germ plasm organizer, Bucky ball, in chicken oocytes and follicles.

Maternal germ plasm determines the germline in birds. Previously, we proposed the chicken-specific Bucky ball (cBuc) as a functional equivalent of the zebrafish germ plasm organizer. This study demonstrated the maternal cBuc synthesis, and verified a highly dynamic distribution of Bucky ball from oocyte nests to maturing follicles using specific antibodies. The dynamic re-localization of cBuc from the ovarian stroma to the granulosa cells, and the Balbiani structure of the oocyte was revealed. Following the accumulation of cBuc in the Balbiani body, an increased signal of chicken vasa homolog (CVH) in close contact to cBuc could be detected. Highest transcription of cBuc was recorded in follicles with diameters up to 500µm. First RNA-interference experiments in an in-vivo follicle culture assay revealed inhibiting effects on cBuc in small follicles. These data demonstrate the maternal origin of cBuc, and underpin its role as germ plasm organizer.

Application of ultrasonic imaging technology in beef cattle breeding management

ObjectiveThe aim of this study was to explore in depth the application of ultrasonic imaging technology in beef cattle reproduction management in order to improve the efficiency and management of beef cattle reproduction. MethodsIn this study, ultrasonographic diagnostic techniques were used to follow up the follicles and corpus luteum in the uterus and ovaries of dairy cows at different stages of development as well as at different periods of gestation of dairy cows, and to detect the effects of different fattening conditions of the cows and the number of litters on the sitting rate. ResultsThe diameter of mature follicles was generally around 16 mm, and the majority of them were 11–20 mm in diameter. Ultrasonography was used to detect early pregnancy in cows at 33–55 d. Ultrasound was used to identify the sex of the foetus most easily at 70–80 d. The results of this study showed that the sex of the foetus was most easily identified in cows at 70–80 d. The fat of the cow and the number of births also had a significant impact on pregnancy rates. ConclusionUltrasound imaging technology has an important application value in the management of beef cattle reproduction, and in pregnancy detection, it can achieve early and accurate diagnosis, improve the accuracy of detection, and differentiate between heifers in estrus and pregnant heifers. In addition, it can also be used for foetal sex identification at a specific period of time, providing a basis for breeding programmes.

Research Progress on Luteinizing Hormone and Polycystic Ovary Syndrome

Polycystic ovary syndrome is a common endocrine disease in women of childbearing age, with an incidence of about 6% to 10%, which is the main cause of anovulatory infertility. With the development of assisted reproductive technology, up to 60% of patients with polycystic ovary syndrome need to be pregnant successfully through in vitro fertilization and embryo transfer. Ovarian controlled ovulation induction is an important process in assisted reproductive therapy. Luteinizing hormone plays an important role in the development and maturation of follicles in the ovary, and high levels of luteinizing hormone have a negative effect on pregnancy outcome. at present, it is still controversial that the appropriate level of luteinizing hormone will improve the pregnancy outcome, and the mechanism of how luteinizing hormone affects the pregnancy outcome is still unclear. This article will mainly review the above two aspects in order to provide reference for clinical research in the future.

Y box-binding protein 1 regulates zebrafish folliculogenesis partly through p21-mediated control of follicle cell proliferation.

Y box-binding protein 1 (Ybx1/ybx1) regulates gene expression through DNA/RNA binding. In zebrafish, Ybx1 is highly abundant in primary growth (PG) follicles in the ovary, but decreases precipitously as the follicles enter the secondary growth (SG). To understand Ybx1 function in folliculogenesis, we created a ybx1 mutant using TALEN and observed disrupted folliculogenesis during the previtellogenic (PV) to early vitellogenic (EV) transition of SG, resulting in underdeveloped ovaries and infertility. Expression and western blot analyses revealed differential gene expression between ybx1-/- and control ovaries, with significantly increased expression of cdkn1a (p21), a cell cycle inhibitor, in ybx1-/- follicles. While cdkn1a knockout via CRISPR/Cas9 was embryonically lethal, the heterozygote (cdkn1a+/-) displayed advanced follicle activation and maturation, contrasting with the ybx1-/- phenotype. Partial loss of p21 alleviated the ybx1-/- phenotype, restoring folliculogenesis with normal PG-PV and PV-EV transitions in ybx1-/-;cdkn1a+/- mutants. While ybx1-/- mutant follicle cells displayed poor proliferation in vivo and in vitro, the cells from the ybx1-/-;cdkn1a+/- follicles resumed normal proliferation. In conclusion, Ybx1 is crucial for early folliculogenesis in zebrafish, potentially by repressing cdkn1a expression, either directly or indirectly.

TsRNA-00764 Regulates Estrogen and Progesterone Synthesis and Lipid Deposition by Targeting PPAR-γ in Duck Granulosa Cells.

Transfer RNA-derived small RNAs (tsRNAs) are novel regulatory small non-coding RNAs that have been found to modulate many life activities in recent years. However, the exact functions of tsRNAs in follicle development remain unclear. Follicle development is a remarkably complex process that follows a strict hierarchy and is strongly associated with reproductive performance in ducks. The process of converting small yellow follicles into hierarchal follicles is known as follicle selection, which directly determines the number of mature follicles. We performed small RNA sequencing during follicle selection in ducks and identified tsRNA-00764 as the target of interest based on tsRNA expression profiles in this study. Bioinformatics analyses and luciferase reporter assays further revealed that peroxisome proliferator-activated receptor-γ (PPAR-γ) was the target gene of tsRNA-00764. Moreover, tsRNA-00764 knockdown promoted estrogen and progesterone synthesis and lipid deposition in duck granulosa cells, while a PPAR-γ inhibitor reversed the above phenomenon. Taken together, these results demonstrate that tsRNA-00764, differentially expressed in pre-hierarchal and hierarchy follicles, modulates estrogen and progesterone synthesis and lipid deposition by targeting PPAR-γ in duck granulosa cells, serving as a potential novel mechanism of follicle selection. Overall, our findings provide a theoretical foundation for further exploration of the molecular mechanisms underlying follicle development and production performance in ducks.

A preliminary study on the effects of Xiang Shao granules on reproductive endocrinology in drugged ovariectomised rats

ObjectiveTo establish a rat model of pharmacological ovariectomy by GnRH-a injection and to preliminarily investigate the reproductive endocrine effects of Xiangshao granules on pharmacologically ovariectomized rats. Methods: A rat model of pharmacological ovariectomy was established by injecting female rats with Gonadotropin-releasing hormone agonist(GnRH-a).The rats were randomly divided into four groups: GnRH-a injected saline group (GnRH-a + NS); GnRH-a injected oestradiol group (GnRH-a + E2); GnRH-a injected Xiangshao granule group (GnRH-a + Xiangshao), and the control group of saline-injected rats (NS + NS). The number of rats per group was 6.According to observations of the rats' vaginal smears, modelling was determined as successful. Then corresponding drug gavage intervention was administered for 28 days, and rat body weight and anal temperature were measured every other day to adjust the drug intervention amount according to body weight changes. Plasma sex hormone levels (E2, FSH, LH), uterine weight, uterine index and endometrial histomorphological changes, ovarian weight, and ovarian index and ovarian histomorphological changes were measured in each group after the gavage.Results(1) Plasma sex hormone levels (E2, FSH, LH) of the GnRH-a + NS, GnRH-a + E2, and GnRH-a + Xiangshao granule groups were significantly lower than the NS + NS group (P < 0.001), while the E2 level of the GnRH-a + E2 group was higher than that of the GnRH-a + Xiangshao granule group (P < 0.05). The FSH level of the GnRH-a + E2 group was significantly lower than that of the GnRH-a + Xiangshao granule group (P < 0.05). The LH level of the GnRH-a + E2 group was significantly lower than those in the GnRH-a + NS and GnRH-a + Xiangshao granule groups (P < 0.001, P = 0.001). The LH and FSH levels of the GnRH-a + NS and GnRH-a + Xiangshao granule groups were not significantly different (P > 0.05). (2) Compared with the NS + NS group, the uterine weight and uterine index, and ovarian weight and ovarian index of GnRH-a injected rats in each model all significantly decreased (P < 0.001). Between the groups, the uterine weight and uterine index, and ovarian weight and ovarian index of GnRH-a + E2 and GnRH-a + Xiangshao granule groups were all significantly higher than those of the GnRH-a + NS group (P < 0.001, P < 0.05). The uterine weight and uterine index, and ovarian weight and ovarian index of the GnRH-a + E2 group increased compared with the GnRH-a + Xiangshao granule group (P < 0.05). (3) Compared with the NS + NS group, the number of primordial follicles of the GnRH-a + NS, GnRH-a + E2, and GnRH-a + Xiangshao granule groups increased significantly and the number of growing follicles and mature follicles significantly decreased. (4) Rats' uterine wall of the NS + NS and various GnRH-a groups was significantly thinner, with the endothelial layer atrophied, while the uterine wall of the GnRH-a + E2 and GnRH-a + Xiangshao granule groups was thicker obviously, with the number of vaginal folds and blood vessels also increasing. Specifically, the uterus and vagina improvements in the GnRH-a + E2 group were more obvious than in GnRH-a + NS and GnRH-a + Xiangshao granule groups.ConclusionGnRH-a injection can reduce the levels of sex hormones E2, FSH, and LH in rats, causing perimenopausal symptoms such as hot flashes, while Xiangshao and E2 granules could significantly improve such symptoms and exert a slight oestrogenic effect, to a lesser extent than E2 does.Trial registrationNot applicable.

GROSS MORPHOLOGY AND MORPHOMETRICAL STUDY OF FEMALE REPRODUCTIVE TRACT IN SIRUVIDAI CHICKEN DURING LAYING AND BROODINESS PHASE

Avian species reproduce sexually by the fusion of male and female gamete spermatogonia and oogonia-produced by differentiated testes and ovaries. Fertilization is internal and all birds are oviparous. Reproduction in birds entirely varies from other animals. The two essential reproductive organs ere the ovary and oviduct which were involved in the synthesis of egg in adult laying hen. Gross and morphometrical studies were carried out on the female reproductive tract in twelve Siruvidai chicken of which six at laying phase and six at broodiness phase. The birds were reared in Poultry Research Station, Madhavaram, Chennai-51. In laying phase, the left ovary showed mature ovarian follicles whereas the ovary during broodiness phase was in the form of a bunch of grapes with no hierarchical follicles. There was no significant difference in the body weight of the bird during laying and broodiness. The mean length, weight and width of ovary and oviduct had a highly significant difference during laying and broodiness phase. Gross morphology revealed that only the left female reproductive tract was well-developed both during laying and broodiness phase and the morphometric data analyzed will provide a baseline for subsequent studies and also for comparison with other avian species.

Comparative effectiveness of sildenafil citrate and estradiol valerate as adjuvants during clomiphene citrate-assisted ovarian stimulation cycles in patients with unexplained infertility: a double-blind randomized controlled trial

ObjectiveThis study aimed to assess the effect of sildenafil citrate and estradiol valerate as adjuvant therapy during ovarian stimulation cycles with clomiphene citrate in patients with unexplained infertility in Kisangani.MethodA double-blind, randomized controlled trial was conducted for two years at two specialized health facilities in Kisangani (University Clinics of Kisangani and “Clinique des Anges Kisangani”). The population included 148 patients, 74 of whom were on clomiphene citrate + sildenafil citrate (CCSC) regimens and 74 of whom were on clomiphene citrate + estradiol valerate (CCEV) regimens for three months. The primary indicator was the conception rate, with secondary outcomes encompassing endometrial thickness, appearance and vascularity, the number of mature follicles and ovulation rate.ResultsThe two groups were comparable in terms of sociodemographic and clinical characteristics. The mean duration of attempting to conceive was 4.39 years versus 4.36 years (P = 0.839), while the mean AFC was 11.51 versus 11.46 (P = 0.831), in the CCSC group versus CCEV group respectively. Secondary infertility was the most frequent diagnosis in each of the two groups. The biochemical pregnancy rate was comparable between the two groups (P = 0.385), while the clinical pregnancy rate was significantly higher in the CCSC group versus CCEV group (P = 0.04). Both perifollicular flow and the ovulation rate were significantly higher in the CCSC group versus the CCEV group (P = 0.006 and P = 0.002 respectively). However, endometrial vascularity/thickness, and the number of Graafian follicles were not significantly different between the two groups.ConclusionAs an adjuvant, sildenafil increases the rate of clinical pregnancy more than does estradiol in patients with unexplained infertility undergoing ovarian stimulation with clomiphene citrate.Study registrationPACTR 202,310,849,449,401 (Pan African Clinical Trials Registry).

Role of endothelial dysfunction in reducing ovarian reserve in women with chronic salpingophoritis

Chronic salpingophoritis is a critical inflammatory disease of the pelvic organs and is a risk factor of diminished ovarian reserve. Notably, chronic salpingophoritis is accompanied by decreased blood supply in the uterus. Circulation in the peripheral bloodstream of pathological inflammatory factors and immune complexes in the blood contributes to the development of oxidant stress, which damages the endothelium vessels and leads to impairment of its functions. Against the background of long-term pathological reactions in the inflammation center forms a vicious circle, wherein endothelial dysfunction plays a crucial role in the development of sclerotic processes in the ovarian tissues and endocrine function of the organ. These persistent morphofunctional disorders contribute to the delay of follicle maturation, which leads to decreased ovarian reserve. The result of the study reveals that, in women, during the peak of reproductive function, having chronic salpingophoritis and reduced ovarian reserve, blood flow in the ovarian arteries deteriorates. Pronounced changes in the dopplerometric blood flow parameters in the ovarian arteries are caused by damage to the vascular wall such as distortion of its tone and disorders in the production of vasoconstrictors and vasodilators (NO and ET-1). This is exacerbated by blood vessel endothelial thrombogenicity and results in long-term endothelial dysfunction, which contributes to impaired hormonal function of the ovaries. Notably, a persistent disorder of vasodimotor and thrombogenic endothelial function leads to a decrease in recruitment of follicles in the ovaries and reduction in ovarian reserve in the selected patient population.

Short-Term Metformin Therapy in Clomiphene Citrate Resistant PCOS Patients Improves Fertility Outcome by Regulating Follicular Fluid Redox Balance: A Case-Controlled Study.

To determine the effect of short-term metformin administration on follicular fluid (FF) total oxidant status (TOS), total antioxidant status (TAS), oxidative stress index (OSI) and nuclear factor kappa B (NF-kB) in women with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). Fifty-eight patients aged 23-34 who were planned to have intracytoplasmic sperm injection due to clomiphene citrate-resistant PCOS were included in the study. Participants were divided into two groups according to whether they used metformin or not. While 30 of 58 PCOS patients were using short-term metformin in combination with controlled ovarian stimulation, 28 PCOS patients were not using metformin. Metformin was started in the mid-luteal period and continued until the day before oocyte retrieval at 850 mg twice daily. To determine FF-NF-kB, TAS, TOS and OSI values, a dominant follicle ≥17-18 mm in diameter was selected for aspiration. The number of mature follicles and fertilization rates of the metformin group were significantly higher than those not taking metformin. FF-TOS and OSI of the metformin group were significantly lower than those of the group not receiving metformin. Patients receiving metformin had higher FF-TAS than the group not receiving metformin. FF-NF-kB levels of the metformin group were significantly lower than the group not receiving metformin. Insulin resistance, FF-NF-kB and FF-TOS were negatively correlated with the number of mature oocytes. FF-TAS was positively correlated with the number of oocytes. Short-term metformin treatment in clomiphene-resistant PCOS improves the number of mature follicles and fertilization rates by regulating the intra-follicle redox balance.

Downregulation of glucose-energy metabolism via AMPK signaling pathway in granulosa cells of diminished ovarian reserve patients

Glucose metabolism plays a crucial role in the function of granulosa cells (GCs) and the development of follicles. In cases of diminished ovarian reserve (DOR), alterations in these processes can impact female fertility. This study aims to investigate changes in glucose-energy metabolism in GCs of young DOR patients aged 20 to 35 years and their correlation with the onset and progression of DOR. 72 DOR cases and 75 women with normal ovarian reserve (NOR) as controls were included based on the POSEIDON and Bologna criteria. Samples of GCs and follicular fluid (FF) were collected for a comprehensive analysis involving transcriptomics, metabolomics, RT-qPCR, JC-1 staining, and flow cytometry. The study identified differentially expressed genes and metabolites in GCs of DOR and NOR groups, revealing 7 common pathways related to glucose-energy metabolism, along with 11 downregulated genes and 14 metabolites. Key substances in the glucose-energy metabolism pathway, such as succinate, lactate, NADP, ATP, and ADP, showed decreased levels, with the DOR group exhibiting a reduced ADP/ATP ratio. Downregulation of genes involved in glycolysis (HK, PGK, LDH1), the TCA cycle (CS), and gluconeogenesis (PCK) was observed, along with reduced glucose content and expression of glucose transporter genes (GLUT1 and GLUT3) in DOR GCs. Additionally, decreased AMPK pathway activity and impaired mitochondrial function in DOR suggest a connection between mitochondrial dysfunction and disrupted energy metabolism. Above all, the decline in glucose-energy metabolism in DOR is closely associated with its onset and progression. Reduced glucose uptake and impaired mitochondrial function in DOR GCs lead to internal energy imbalances, hindering the AMPK signaling pathway, limiting energy production and supply, and ultimately impacting follicle development and maturation.

Phylogenomic insights into Neotropical Magnolia relationships

Despite extensive research into the phylogenetic relationships of the genus Magnolia, Neotropical taxa have been neglected. This is partly because their numbers have recently doubled and now account for almost half of the global richness. Therefore, by sampling one-third of all Neotropical taxa their relationships were studied using morphological, nuclear, and plastome data. Two major clades were identified: Clade I, comprising Magnolia sect. Talauma, Magnolia sect. Splendentes from the Neotropics, and the Asian Magnolia sect. Gwillimia; while Clade II included the Neotropical clades Magnolia sect. Macrophylla and Magnolia sect. Magnolia, along with the remaining non-Neotropical sections. Within Clade I, Magnolia sect. Talauma was geographically divided into a northern subclade grouping Mexican and Central American taxa, and a southern subclade comprising South American and Caribbean taxa. Magnolia sect. Splendentes was also dichotomously divided, corresponding to the former Magnolia sect. Talauma subsect. Cubenses and Magnolia sect. Talauma subsect. Dugandiodendron. In Clade II, the relationships within Magnolia sect. Macrophylla and Magnolia sect. Magnolia were unclear, suggesting a species complex in all Magnolia sect. Macrophylla taxa. In total, 25 morphological traits were assessed, and ancestral state reconstructions were carried out. Only the joined clustering of mature follicles was a synapomorphy for the southern subclade of Magnolia sect. Talauma. In conclusion, this highlights the need to re-assess the taxonomic delimitation of certain groups, to update the infrageneric classification of Neotropical clades and to explore morphological traits to support them.

FecBB mutation enhances follicle stimulating hormone sensitivity of granulosa cells by up-regulating the SMAD1/5–USF1–FSHR signaling pathway

The FecBB mutation, a single-point mutation (c.A746G; p.Q249R) in bone morphogenetic protein receptor type 1 B (BMPR1B), is associated with increased ovulation quotas and litter size in sheep. However, the regulatory mechanism of the FecBB mutation in increased fecundity remains to be elucidated. Therefore, creating an immortal cell model harboring the FecBB mutation would elucidate the regulatory mechanism of this mutation. Here, we report the creation of a human granulosa cell, COV434, model containing a homozygous FecBB mutation through homology-directed repair (HDR) induced by clustered, regularly-interspaced, short palindromic repeats–CRISPR-associated protein 9 along with a single-stranded oligodeoxynucleotide (ssODN) template. We found that the FecBB mutation enhanced the basal SMAD1/5 signaling activity in COV434 cells, leading to increased expression of FSHR, probably through increased formation of the SMAD1/5–SMAD4 complex to bind to the SBE element, which in turn promotes the binding of USF1 to the regulatory element E-box in the promoter of FSHR. Furthermore, the FecBB mutation substantially enhanced estradiol (E2) synthesis in granulosa cells under follicle stimulating hormone (FSH) stimulation, indicating an enhanced sensitivity to FSH, which may promote the growth of more small follicles into mature follicles, leading to increased fecundity. Our study provides novel insights into the possible regulatory mechanisms of FecBB mutations in increased fecundity.

TREATMENT OUTCOMES IN PCOS (POLYCYSTIC OVARIAN SYNDROME)-RELATED INFERTILITY

Polycystic ovarian syndrome (PCOS) is one of the underdiagnosed endocrine disorders found to be prevalent among females in the reproductive age group. PCOS effects on an average 8-13% of reproductive aged women, globally. This condition is responsible for causing distress physiologically and psychologically paving the way for a poor quality of life. One of the devastating complications of PCOS is infertility. At present, there is no treatment for PCOS but could be managed by alternate options such as lifestyle modification to in-vitro fertilization. The primary objective of this review article is to analyze the outcomes of certain pharmacological treatment options such as clomiphene citrate which is a selective estrogen receptor modulator, Letrozole an aromatase inhibitor, and gonadotropins for PCOS-related infertility. Clomiphene citrate binds to estrogen receptors indirectly increasing the gonadotropins. Studies confirm a 35-40% successful outcome. Letrozole similarly increases gonadotropins by indirectly decreasing estrogen. A notable increase in the successful outcome was observed with both clomiphene citrate and letrozole, with almost near similar results. The pregnancy outcome was approximately 40% with clomiphene citrate, while letrozole showed 50%. Notably, more side effects were observed in the administration of clomiphene citrate compared to letrozole. Human menopausal gonadotropin (hMG) and recombinant follicle-stimulating hormone (FSHr), that are gonadotropins, were used as they are directly responsible for the maturation of follicles and ovulation itself. The use of gonadotropins increased the pregnancy rate outcome to 20 -30 %, albeit with the risk of multiple births. Furthermore, we have discussed why letrozole and clomiphene citrate are used as the primary therapy compared to gonadotropins. Peer Review History: Received 22 May 2024; Reviewed 14 July 2024; Accepted 23 August; Available online 15 September 2024 Academic Editor: Dr. Rola Jadallah, Arab American University, Palestine, rola@aauj.edu Average Peer review marks at initial stage: 5.5/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. George Zhu, Tehran University of Medical Sciences, Tehran, Iran, sansan4240732@163.com Dr. Ogbonna B. Onyebuchi, Nnamdi Azikiwe University, Awka, Nigeria, summitpharm@yahoo.com

7 Role of the preovulatory follicle in oocyte metabolic and developmental competence for pregnancy

Abstract A majority of bovine pregnancy loss occurs in the first 7 d of gestation. The oocyte is a key driver of embryo viability during this time, and its competence for embryo development and pregnancy establishment is greatly influenced by the surrounding microenvironment during oocyte maturation. Assisted reproductive technologies allow for more efficient propagation of superior genetics and improved reproductive management of the cattle herd; however, many assisted reproductive technologies alter the normal microenvironment of the maturing oocyte and negatively impact oocyte competence for early embryo development. For example, oocytes induced to ovulate from preovulatory follicles of lesser physiological maturity (decreased estradiol production and smaller diameter) have reduced blastocyst development, poorer embryo quality, and a hastened rate of embryo development compared with those ovulated from follicles of greater maturity. Our overarching hypothesis is that the intrafollicular milieu of physiologically mature preovulatory follicles provides the necessary microenvironment to metabolically program maturing oocytes for successful embryo development. Studies by our team have demonstrated that the follicular fluid metabolite milieu during in vivo oocyte maturation differs between preovulatory follicles of greater and lesser maturity and that such differences have direct effects on the maturing oocyte. Numerous follicular fluid metabolites involved in glucose and amino acid metabolism were more abundant in preovulatory follicles of greater versus lesser physiological maturity. Additionally, abundance of transcripts encoding glycolytic enzymes was higher in cumulus cells from follicles of greater maturity, and both ATP and levels of key transcripts in the mitochondrial respiratory chain were higher in oocytes collected from preovulatory follicles of greater versus lesser maturity. We supplemented in vitro maturing oocytes with follicular fluid from preovulatory follicles of greater or lesser maturity to determine causality of differing follicular fluid milieu on cumulus-oocyte metabolism and oocyte competence for early embryo development. Follicle maturity status had robust effects on cumulus-oocyte complex consumption or production of key metabolites in glucose, purine, and amino acid metabolism pathways during oocyte maturation. We also observed hastened development rate in embryos arising from in vitro matured oocytes supplemented with lesser maturity follicular fluid, mirroring past in vivo findings by others. Furthermore, RNA-sequencing of resulting blastocysts of identical stage and quality suggested more efficient metabolism and Wnt/β-catenin signaling in blastocysts derived from oocytes matured in preovulatory follicular fluid from greater maturity follicles. In contrast, transcriptome profiles of blastocysts from oocytes matured in preovulatory follicular fluid from lesser maturity follicles indicated oxidative stress and dysregulated cell division. These recent findings by our lab indicate that impacts of follicle maturity and the resulting follicular fluid microenvironment on the maturing oocyte withstand throughout early embryo development and hold promising roles to improve reproductive efficiency in cattle.

Luteinizing hormone supplementation with human menopausal gonadotropin versus low dose human chorionic gonadotropin during ovarian stimulation does not affect live birth rates after fresh and frozen embryo transfer.

Luteinizing hormone (LH) plays an important role in ovarian follicle maturation. Human menopausal gonadotropin (hMG) or low dose human chorionic gonadotropin (hCG) can provide LH supplementation during in vitro fertilization (IVF) ovarian stimulation, though studies directly comparing their impact on IVF outcomes are limited. The aim of the study was to determine whether LH supplementation with hMG versus low dose hCG during IVF stimulation affects live birth rate. Fresh and frozen embryo transfers (ET) from 2017 to 2021 after standard long or antagonist protocols supplemented with hMG (75-250 IU) or low dose hCG (50-100 IU) during stimulation cycles in our academic center were included. Statistical analysis was performed with T-tests, Mann-Whitney U tests, Chi-square, and multiple linear and logistic regression. Four hundred and sixty eight unique stimulation cycles resulting in 213 fresh and 412 frozen embryo transfers were analyzed. There was a lower mature oocyte yield (10.9 vs. 11.8, p = 0.044) but similar high-quality blastocyst yield (3.6 vs. 3.9, p = 0.11) for hMG vs low dose hCG. Live birth rates per transfer were comparable for fresh (42% vs. 49%, p = 0.24) and frozen (46% vs. 53%, p = 0.45) embryo transfers. Multiple logistic regressions showed no association between supplemental gonadotropin and live birth for both fresh and frozen embryo transfers. Fresh and frozen IVF-ET pregnancy outcomes were comparable after hMG versus low dose hCG supplementation, suggesting flexibility in supplemental LH dosing regimens that may address patient or physician preference or cost concerns.

Significance of FSHR and LHCGR gene polymorphisms on clinical outcomes in gonadotropin-releasing hormone antagonist protocol with freeze-all strategy: A case-control study.

Follicle-stimulating hormone receptor (FSHR) and luteinizing hormone/choriogonadotropin receptor (LHCGR) are integral to ovarian function, facilitating follicle development and maturation through their respective hormonal interactions. The influence of receptor polymorphisms on the outcomes of freeze-all cycles remains unclear. This study investigates the impact of FSHR N680S and LHCGR N312S polymorphisms on clinical outcomes in freeze-all cycles. Women undergoing controlled ovarian stimulation for assisted reproductive technology participated in this study. They were administered a gonadotropin-releasing hormone antagonist protocol, with recombinant follicle-stimulating hormone (rFSH) dosages adjusted according to age, body mass index, antral follicle count, and individual hormonal responses. Additionally, human menopausal gonadotropin dosages were tailored based on the LHCGR N312S genetic variant. Analysis revealed no significant differences in age, body mass index, antral follicle count, or marital status across the genotypes of FSHR N680S and LHCGR N312S. However, notable differences were observed in the rFSH dosage required daily and in total among the FSHR polymorphism genotypes. Genotypes of the LHCGR polymorphism correlated with fewer stimulation days. A significant interaction was observed between the 2 polymorphisms concerning total rFSH dosage. The presence of serine in the FSHR polymorphism was associated with higher rFSH dosage requirements. Both FSHR N680S and LHCGR N312S polymorphisms significantly influenced clinical pregnancy and live birth outcomes in freeze-all cycles, underscoring the potential of a pharmacogenomic approach to optimize hormone supplementation in controlled ovarian stimulation protocols during assisted reproductive technology treatments.

InDel mutations within the bovine PER2 gene are significantly associated with reproductive traits.

Functioning as a key regulator of circadian rhythms, the PER2 gene exerts a substantial impact on the reproductive traits of animals. However, the effect of the PER2 gene on ovarian development remains unclear. In order to examine the relationship between bovine reproductive trait and the PER2 gene, a total of 901 ovarian samples were collected, categorized into different oestrus cycles (proestrus, oestrus, post-oestrus, anoestrous), and subjected to analysis for two potential insertion/deletions (InDels) in the PER2 gene. Through agarose gel electrophoresis and DNA sequencing, two polymorphic deletion mutations (P2-D5-bp, P3-D13-bp) were identified. Furthermore, a significant association between mature follicle diameter and P2-D5-bp was found (P < 0.05). Additionally, several significant correlations with ovarian length, width, height, and white body diameter were found for P3-D13-bp (P < 0.05). These findings suggested that the bovine PER2 gene plays an important role in above-mentioned reproductive traits, offering new avenues for improving cow fertility through marker-assisted selection (MAS).

Local Regulatory Changes of HSD11B1 and NR3C1 in the Follicular and Luteal Tissue During Experimentally Induced Ovulation in the Cow.

The objective of the study was to characterise the expression patterns of the two key components of cortisol action namely HSD11B1 (11-beta-hydroxysteroid dehydrogenase type 1) and NR3C1 (nuclear receptor subfamily 3, group C, member 1, also known as the glucocorticoid receptor) in superovulation induced bovine follicles during the periovulation and subsequent corpus luteum (CL) formation. Bovine ovaries containing preovulatory follicles or CL were timely defined during induced ovulation as follows: 0 h before GnRH (Gonadotropin-releasing hormone) application, and 4, 10, 20, 25 (follicles) and 60 h (early CL) after GnRH. The low mRNA expression of HSD11B1 and NR3C1 in the follicle group before the GnRH application increased significantly in the follicle group 20 h after GnRH and remained high afterward also in the early CL group. In contrast, the high NR3C1 mRNA decreased in follicles 25 h after GnRH (close to ovulation) and significantly increased again after ovulation (early CL). Our results indicated the involvement of HSD11B1 and NR3C1 as the two key components of cortisol action in the local mechanisms coordinating final follicle maturation, ovulation, follicular-luteal transition and CL development in the cow.

Impact of Letrozole on Mature Follicle Rate in Treatment of Subfertility Due to Polycystic Ovarian Syndrome

Impact of Letrozole on Mature Follicle Rate in Treatment of Subfertility Due to Polycystic Ovarian Syndrome