Mature Follicles Research Articles

The influence of concomitant extragenital pathology on the success of assisted reproductive technology procedures in women (according to clinics of the Volgograd region)

At the moment, the problem of infertility does not lose its relevance. In the structure of this disease, the violation of reproductive function in women is dominant. The present study is devoted to the study of the influence of concomitant extragenital pathology on the success of assisted reproductive technology procedures. The data of 184 women who underwent infertility treatment by ART methods in clinics of the Volgograd region in the period from 2015 to 2020 were analyzed. The following parameters of the patients were studied: age, gynecological history, the main cause of infertility, transferred diseases of non-productive organs, the protocol of ovarian stimulation with gonadotropins, the number of mature follicles by the end of stimulation, the number of received, fertilized eggs, the number of embryos by day 3, 5. It has been established that concomitant extragenital pathology affects the processes of folliculogenesis and qualitatively affects oogenesis.

Dysregulated Liver Metabolism and Polycystic Ovarian Syndrome.

A significant fraction of couples around the world suffer from polycystic ovarian syndrome (PCOS), a disease defined by the characteristics of enhanced androgen synthesis in ovarian theca cells, hyperandrogenemia, and ovarian dysfunction in women. Most of the clinically observable symptoms and altered blood biomarker levels in the patients indicate metabolic dysregulation and adaptive changes as the key underlying mechanisms. Since the liver is the metabolic hub of the body and is involved in steroid-hormonal detoxification, pathological changes in the liver may contribute to female endocrine disruption, potentially through the liver-to-ovary axis. Of particular interest are hyperglycemic challenges and the consequent changes in liver-secretory protein(s) and insulin sensitivity affecting the maturation of ovarian follicles, potentially leading to female infertility. The purpose of this review is to provide insight into emerging metabolic mechanisms underlying PCOS as the primary culprit, which promote its incidence and aggravation. Additionally, this review aims to summarize medications and new potential therapeutic approaches for the disease.

Adipose-derived stem cells promote the repair of chemotherapy-induced premature ovarian failure by inhibiting granulosa cells apoptosis and senescence

BackgroundChemotherapeutic drugs, particularly alkylating cytotoxics such as cyclophosphamide (CTX), play an important role to induce premature ovarian failure (POF). Hormone replacement therapy (HRT) is a widely used treatment to improve hormone secretion. However, the long-term HRT increases the risk of breast cancer and cardiovascular disease are attracting concerns. Therefore, there is an urgent need to develop a safe and effective treatment for POF.MethodAdipose-derived stem cells (ADSCs) were isolated and identified from human adipose tissue. For POF modeling, CTX were intraperitoneal injected into CTX-acute group, CTX-chronic group, CTX-acute + ADSCs group and CTX-chronic + ADSCs group rats; For transplantation, ADSCs were transplanted into POF rats through tail-vein. The control group rats were injected with PBS. The effects of POF modeling and transplantation were determined by estrous cycle analysis, histopathological analysis, immunohistochemical staining and apoptosis-related marker. To evaluate the effects of ADSC on granulosa cells in vitro, CTX-induced senescent KGN cells were co-cultured with ADSCs, and senescent-related marker expression was investigated by immunofluorescent staining.ResultsIn vivo studies revealed that ADSCs transplantation reduced the apoptosis of ovarian granulosa cells and secretion of follicle-stimulating hormone. The number of total follicles, primordial follicles, primary follicles, and mature follicles and secretion of anti-Müllerian hormone and estradiol (E2) were also increased by ADSCs. The estrous cycle was also improved by ADSC transplantation. Histopathological analysis showed that CTX-damaged ovarian microenvironment was improved by ADSCs. Furthermore, TUNEL staining indicated that apoptosis of granulosa cells was decreased by ADSCs. In vitro assay also demonstrated that ADSC markedly attenuated CTX-induced senescence and apoptosis of granulosa cell. Mechanistically, both in vivo and in vitro experiments proved that ADSC transplantation suppressed activation of the PI3K/Akt/mTOR axis.ConclusionOur experiment demonstrated that a single injection of high-dose CTX was a less damaging chemotherapeutic strategy than continuous injection of low-dose CTX, and tail-vein injection of ADSCs was a potential approach to promote the restoration of CTX-induced POF.

Transcription factors Dmrt1a, Foxl2, and Nr5a1a potentially interact to regulate cyp19a1a transcription in ovarian follicles of ricefield eel (Monopterus albus)

Aromatase (encoded by Cyp19a1) in the ovarian follicular cells catalyzes the production of estradiol from testosterone, which plays important roles in the ovarian development of vertebrates. In the present study, the interaction of Dmrt1, Foxl2, and Nr5a1a on the regulation of cyp19a1a transcription in ovarian follicles was examined in a teleost, the ricefield eel Monopterus albus. The expression of dmrt1a, foxl2, and nr5a1a was detected in ovarian follicular cells together with cyp19a1a at the mRNA and/or protein levels. Sequence analysis identified one conserved Foxo binding site in the proximal promoter region of ricefield eel cyp19a1a. Transient transfection assay showed that Foxl2 may bind to the conserved Foxo site to activate cyp19a1a transcription and act synergistically with Nr5a1a. Mutation of either the conserved Nr5a1 site or Foxo site abolished or significantly decreased the synergistic effects of Nr5a1a and Foxl2 on cyp19a1a transcription. The sequence between Region III and I-box of Nr5a1a was critical to this synergistic effect. Dmrt1a modulated the Foxl2- and Nr5a1a-induced activation of cyp19a1a transcription and their synergistic effects in a biphasic manner, with inhibitory roles observed at lower doses (10–50 ng) but release of the inhibition or even potentiating effects observed at higher doses (100–200 ng). Collectively, data of the present study suggest that the interaction of Dmrt1a, Foxl2, and Nr5a1a in the ovarian follicular cells may facilitate the adequate expression of cyp19a1a and the production of estradiol, and contribute to the development and maturation of ovarian follicles in ricefield eels and other vertebrates as well.

Bioceutical role of nano and organic selenium on certain reproductive value of laying hen during force molting

Nanotechnology has proposed many new effective forms of nutritional supplement ingredients due to their low toxicity and high bioavailability, among which are nano-selenium, due to their distinctive properties of small particles and increased surface area of ​​compounds, allowing the opportunity for biological interactions. In this study, 48 laying hens, aged 47 weeks, of a rose type were used, and the experiment lasted for two months. The birds were fed two types of diets, one standard and the other a non-standard diet, represented by the use of crushed yellow corn for molting. The birds were divided into six groups 8 birds/group, with the first group receiving a standard diet, the second group receiving only yellow tops crushed, the third group receiving organic-Se 2 g/L with a standard diet, the fourth group receiving Nano-Se 0.5 ml/L with standard stalk, the fifth group receiving organic- Se with straw 2 g/L, and the sixth group receiving nano-Se with straw 0.5 ml/L. The results showed a significant rise in ovary weight, oviduct weight, number of immature and mature follicles, FSH, LH, as well as an improvement in the histological characteristics of the shell gland in the groups treated with nano and organic-Se, indicating that nano-Se plays a critical role in restoring most reproductive and histological parameters to their normal levels, close to the baseline. This study found that organic and nano-Se are crucial in improving most reproductive and physiological parameters of laying hens exposed to molting.

Therapeutic impact of letrozole and clomiphene citrate for ovulation induction in Iraqi female patients with polycystic ovary syndrome

Introduction: Clomiphene citrate (CC) is the most commonly used ovulation induction agent in women with polycystic ovary syndrome (PCOS). Letrozole has attracted attention for its ovulation induction effects as a safe, potentially better alternative to CC. The aim of this study was to compare the therapeutic efficacy of letrozole in comparison to CC for ovulation induction in female patients with PCOS in Baghdad Province, Iraq. Materials and Methods: A prospective, randomized, controlled study was carried out on 166 female patients diagnosed with anovulatory infertility due to PCOS and randomly assigned into two groups. Group A included ninety-four participants who received CC. Group B included 85 participants who received letrozole. The main outcomes were the ovulation induction and therapeutic outcomes of CC and letrozole, including endometrial thickness, number of mature follicles, pregnancy rate, number of stimulated cycles and mono-ovulation rate. Results: Endometrial thickness improved significantly more with CC than with letrozole (8.08 ± 1.28 vs. 7.66 ± 1.41; P = 0.05), as did the number of mature follicles (3.07 ± 1.23 vs. 1.97 ± 0.83; P = 0.0001). Nevertheless, Group B patients reported a higher significant rate compared to Group A regarding pregnancy rate (62% vs. 38%; P < 0.01), number of stimulated cycles (91% vs. 78%; P < 0.05), and mono-ovulation rate (29% vs. 5.75%; P = 0.0001). Conclusion: Letrozole is preferable to CC in terms of a higher pregnancy rate as well as mono-follicles' ability to decrease the risk of multiple pregnancies, which is clearly observed with CC. The higher success of letrozole over CC is thought to be related to the higher ovulation rate per cycle. The following core competencies are addressed in this article: Patient care and procedural skills, medical knowledge.

Cedrus deodara (Roxb. ex D.Don) G.Don bark fraction ameliorates metabolic, endocrine and ovarian dynamics in rats experiencing polycystic ovarian syndrome.

In the Ayurvedic system of medicine, Cedrus deodara bark has been utilized as a folk medicine to remove ovarian cysts and treat infertility in females. The present study is the first to investigate ameliorating potential of C. deodara bark on testosterone propionate and high-fat diet-induced polycystic ovarian syndrome in experimental rats. LC-MS analysis of the fraction selected through bioassay-guided approach employing uterine relaxant activity was performed to determine the bioactive constituents present in it. Further, the identified compounds were docked on the catalytic site of the androgen receptor and insulin receptor substrate-1. Later, the fraction was investigated against testosterone propionate and high-fat diet-induced PCOS in rats. Chloroform fraction (F1) of the plant bark was found most active in uterine smooth muscle relaxant activity. LC-MS analysis of F1 indicated the presence of key flavonoids namely deodarin, cedrin, deodardione, and cedrusinin. Afterward, a molecular docking study of these compounds revealed impressive binding interactions with androgen receptor and insulin receptor substrate-1. Besides, in vivo studies, treatment with F1 significantly restored the estrous cycle in rats from the diestrus phase in a dose-dependent manner. Also, the disturbed metabolic and endocrine profile was markedly improved in rats. Later, histopathological analysis revealed the presence of a large number of mature follicles and corpora lutea in F1-treated rats. In a nutshell, F1 exhibited promising beneficial effects in PCOS and associated conditions via amelioration of metabolic, endocrine, and ovarian dynamics in experimental rats.

Does controlled ovarian stimulation during in vitro fertilization affect the level of nitric oxide a potential indicator of oocyte quality?

Infertility is a major global health issue, affecting approximately 9% of couples worldwide. Its prevalence increased steadily over the preceding decades, paralleling environmental and lifestyle changes. One assisted reproductive technique to overcome infertility is in vitro fertilization (IVF). The IVF procedure consists of several stages, one of which is controlled ovarian stimulation (COS) via various protocols allowing follicular recruitment and maturation in preparation for oocyte retrieval. Follicular fluid (FF) is the microenvironment in which oocytes develop during folliculogenesis, and FF information could be used to assess follicle and oocyte development and maturation stages. Nitric oxide (NO) is a component of FF that is being studied as a predictive factor of follicle maturation and egg quality and as a potential indicator of the success of COS during the IVF process. The hypothesis was that COS affects NO levels in the serum; more specifically, that NO levels in serum after COS correlate with NO levels in FF, based on literature data on the influence of female reproductive hormones on NO metabolism and data on the change in the hormonal milieu affected by COS use.Furthermore, it was hypothesized that NO levels in serum and FF after COS were related to the number of high-quality female reproductive cells obtained during IVF. Assuming that NO levels in serum after COS correlate with NO levels in FF, the central hypothesis of this study is that serum NO levels after COS could be a valuable predictor of oocyte quality and the number of high-quality female reproductive cells achieved by COS. As a result of the hypothesis, measuring NO could be a novel way to improve the efficiency of IVF treatment.

Protective effect of wuzibushen recipe on follicular development via regulating androgen receptor in polycystic ovary syndrome model rats

Objectives The study aimed to explore the role and mechanism of WZBS recipe on PCOS. Methods PCOS model was established. After modeling, PCOS rats were intragastrically administered with Diane-35 or WZBS recipe (6.93 g/kg/d). Then, the ovarian and uterine morphology were observed, the estrous cycle was assessed. HE and oil red O staining were conducted for ovarian morphological analysis and counting ovarian follicle and corpora lutea number. Furthermore, the serum content of testosterone (T) and sex-hormone-binding globulin (SHBG) were assessed by ELISA kits. The androgen receptor (AR), CX43 mRNA and protein expression were measured by q-PCR and Western blot. Results WZBS recipe increased uterine implanted blastocysts, reduced cystic dilated follicles, and normalized estrous cycle in PCOS rats. Meanwhile, WZBS recipe alleviated ovarian injury, increased mature follicles and corpora lutea number in PCOS rats. Moreover, WZBS recipe decreased serum T content, AR expression and increased serum SHBG content, CX43 expression in PCOS rats. Conclusions This study reveals that WZBS recipe may attenuate PCOS by protecting follicular development via down-regulating AR.

THE EFFECT OF AROMATASES INHIBITOR-BASED PRODUCTS ON COW REPRODUCTIVE ABILITY

Mycotoxin zearalenone is a phytoestrogenic substance that can disrupt the functioning of the organs of the reproductive system of cows. At the same time, a hyperestrogenic state occurs, which
 leads to overeating, multiple unsuccessful inseminations and infertility of cows.
 The purpose of the research is to investigate the effect of a single application of drugs based on aromatase inhibitors on the main biochemical and hormonal parameters of the blood of cows, as well as to establish their effectiveness during spontaneous expression of desire and when applying synchronization schemes.
 The effect of a single dose of aromatase inhibitors on the dynamics of sex hormones in cows, which directly affect the formation of the dominant follicle and its ovulation, was investigated. At the same time, a 1.56-fold decrease in estradiol, a 1.67-fold increase in progesterone, a 1.29-fold increase in luteinizing hormone, and a 1.76-fold increase in follicle-stimulating hormone were found. At the same time, the maturation of the dominant follicle and its ovulation at a size of 22 to 24 mm have been established. A change in the biochemical parameters of the blood serum of cows after the use of products based on an aromatase inhibitor was revealed. A tendency was established to restore the level of calcium to 2.01±0.27 mmol/l, phosphorus – 1.1±0.41 mmol/l, magnesium – 0.87±0.11 mmol/l, selenium –1.0± 0.1 mmol/l. At the same time, the level of creatinine decreased by 1.2 times compared to sick animals, the indicators of liver transferases also tended to decrease. A significant decrease in the blood urea index by 1.69 times was established, which indicates the restoration of protein and lipid metabolism.
 The indicators of fertilization of cows with spontaneous manifestation of sexual desire when using agents based on aromatase inhibitors were studied. At the same time, the fertility rate ranged from 69.39% in cows older than 5 years to 80.39% in cows after the 1st calving.
 A positive effect of aromatase inhibitors, introduced before the use of estrus synchronization schemes in cows, was established on the development of the dominant follicle, luteogenesis and the appearance of a new wave of follicle development. Fertilization averaged from 68.1% to 76.42%.

Kobayashi Award 2021: Neuropeptides, receptors, and follicle development in the ascidian, Ciona intestinalis Type A: New clues to the evolution of chordate neuropeptidergic systems from biological niches

Ciona intestinalis Type A (Ciona robusta) is a cosmopolitan species belonging to the phylum Urochordata, invertebrate chordates that are phylogenetically the most closely related to the vertebrates. Therefore, this species is of interest for investigation of the evolution and comparative physiology of endocrine, neuroendocrine, and nervous systems in chordates. Our group has identified>30 Ciona neuropeptides (80% of all identified ascidian neuropeptides) primarily using peptidomic approaches combined with reference to genome sequences. These neuropeptides are classified into two groups: homologs or prototypes of vertebrate neuropeptides and novel (Ciona-specific) neuropeptides. We have also identified the cognate receptors for these peptides. In particular, we elucidated multiple receptors for Ciona-specific neuropeptides by a combination of a novel machine learning system and experimental validation of the specific interaction of the predicted neuropeptide-receptor pairs, and verified unprecedented phylogenies of receptors for neuropeptides. Moreover, several neuropeptides were found to play major roles in the regulation of ovarian follicle development. Ciona tachykinin facilitates the growth of vitellogenic follicles via up-regulation of the enzymatic activities of proteases. Ciona vasopressin stimulates oocyte maturation and ovulation via up-regulation of maturation-promoting factor- and matrix metalloproteinase-directed collagen degradation, respectively. Ciona cholecystokinin also triggers ovulation via up-regulation of receptor tyrosine kinase signaling and the subsequent activation of matrix metalloproteinase. These studies revealed that the neuropeptidergic system plays major roles in ovarian follicle growth, maturation, and ovulation in Ciona, thus paving the way for investigation of the biological roles for neuropeptides in the endocrine, neuroendocrine, nervous systems of Ciona, and studies of the evolutionary processes of various neuropeptidergic systems in chordates.

Rehmannioside D mitigates disease progression in rats with experimental-induced diminished ovarian reserve via Forkhead Box O1/KLOTHO axis

This study aims to explore the impact of Rehmannioside D (RD) on ovarian functions of rats with diminished ovarian reserve (DOR) and its underlying mechanisms of action. A single injection of cyclophosphamide was performed to establish a DOR rat model, and fourteen days after the injection, the rats were intragastrically administrated with RD for two weeks. Rat estrus cycles were tested using vaginal smears. Ovarian tissues were histologically evaluated, the number of primordial, mature, and atretic follicles was calculated, and the apoptotic rate of granulosa cells. Follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) levels were determined by ELISA assays. Protein levels of Forkhead Box O1 (FOXO1), KLOTHO, Bcl-2, and Bax were investigated in ovarian tissues of DOR rats. The binding between FOXO1 and KLOTHO was verified by ChIP assay. High-dose administration of RD into DOR rats improved their estrus cycles, increased ovarian index, enhanced the number of primordial and mature follicles, reduced the number of atretic follicle number, and ovarian granulosa cell apoptosis in addition to inhibiting FSH and LH levels and upregulating E2 expression. FOXO1 and KLOTHO were significantly suppressed in DOR rats. FOXO1 knockdown partially suppressed the protective effects of RD on DOR rats, and KLOTHO overexpression could restore RD-induced blockade of DOR development despite knocking down FOXO1. FOXO1 antibody enriched KLOTHO promoter, and the binding between them was reduced in DOR group compared to that in sham group. RD improved ovarian functions in DOR rats and diminished granulosa cell apoptosis via the FOXO1/KLOTHO axis.

Biological basis of pest control on pasture flies: as a case study from Uzbekistan

In this article, we aimed at studying the biology of pasture insects using the example of M. Tempestiva, developmental biology, ethology, timing of generations and life expectancy of females and males, changes in the genital organs during the maturation of egg follicles, the duration of nutrition on various substrates, the predominance of nutrition on carbohydrate media. The duration of mating, fertilization, the number of generations according to changes in the ovary of females, the development of eggs and their laying. Duration of all stages of biological development, including egg, larval stages, puparia and mature adults. Phenological dates have been established, i.e. the timing of the increase in the number of pasture insects, therefore, the study of biology and development cycles will allow us to further develop integrated methods for controlling insects in the pasture precisely during the period of their mass parasitism.

Oxytocin receptor (OXTR) is a risk gene for polycystic ovarian syndrome.

Oxytocin (OXT) controls appetite, promotes diet-induced energy expenditure, and may protect against obesity. Furthermore, the oxytocin system controls ovarian follicle luteinization and steroidogenesis as well as adrenal steroidogenesis, which if impaired might lead to anovulation and hyperandrogenism, signs found in women with polycystic ovarian syndrome (PCOS). PCOS is a common complex endocrine disorder of reproductive-age women, and it often presents with impaired glucose metabolism, insulin resistance (IR), and type 2 diabetes (T2D). The oxytocin receptor gene (OXTR) may confer a risk for PCOS, conceivably through dysregulation of metabolism, ovarian follicle maturation, and ovarian and adrenal steroidogenesis. Therefore, we aimed to investigate whether OXTR variants confer risk for PCOS. In 212 Italian subjects with T2D and PCOS, we have analyzed 22 single nucleotide polymorphisms (SNPs) within the OXTR gene for linkage to and/or linkage disequilibrium (LD, i.e., association) with PCOS. We tested whether the significant risk variants were independent or part of an LD block. We found 5 independent variants significantly linked to/in LD with PCOS within the peninsular families. This is the first study to report OXTR as a novel risk gene in PCOS. Functional and replication studies are needed to confirm these results.

Circadian and kisspeptin regulation of the preovulatory surge

Fertility in mammals is ultimately controlled by a small population of neurons – the gonadotropin-releasing hormone (GnRH) neurons – located in the ventral forebrain. GnRH neurons control gonadal function through the release of GnRH, which in turn stimulates the secretion of the anterior pituitary gonadotropins luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In spontaneous ovulators, ovarian follicle maturation eventually stimulates, via sex steroid feedback, the mid-cycle surge in GnRH and LH secretion that causes ovulation. The GnRH/LH surge is initiated in many species just before the onset of activity through processes controlled by the central circadian clock, ensuring that the neuroendocrine control of ovulation and sex behavior are coordinated. This review aims to give an overview of anatomical and functional studies that collectively reveal some of the mechanisms through which the central circadian clock regulates GnRH neurons and their afferent circuits to drive the preovulatory surge.

Thyroid hormone triiodothyronine does not protect ovarian reserve from DNA damage induced by X-ray and cisplatin.

Cancer therapy can induce premature ovarian insufficiency, necessitating methods for preserving fertility in female cancer patients. However, the only accepted clinical practice for doing so is cryopreservation of embryos, unfertilized ova, and ovarian tissue, despite potential options such as in vitro maturation of follicles. Therefore, considerable interest has arisen in fertoprotective agents, with research on rat ovarian granulosa cells suggesting that triiodothyronine (T3) regulates an anti-apoptosis mechanism that protects the ovarian reserve from paclitaxel-induced DNA damage. In this study, we used postnatal day 5 mouse ovary to confirm the existence of T3 thyroid hormone receptor (THR), as well as to investigate the potential protective effects of T3 against cisplatin- and X-ray-induced apoptosis. We also tested the potential anti-apoptotic effect of T3 in the breast cancer cell line MDA-MB-231. We treated cultured mouse ovaries with varying concentration of T3 and 4μM cisplatin and 0.2Gy X-ray. Real-time PCR, histological analysis, immunoblot analysis, and immunofluorescence were performed to assess the potential anti-apoptotic effects of T3. We confirmed that THR alpha and beta are expressed in the mouse ovary. T3 (0.1, 1, 10, 100nM, and 1µM) does not protect ovarian reserve from cisplatin- or X-ray-induced apoptosis or DNA damage. Similarly, it does not protect mouse granulosa cells and MDA-MB-231 cells from cisplatin- or X-ray-induced apoptosis. Our findings suggest that T3 is ineffective as a fertoprotective agent, and its candidacy as a potential agent to preserve fertility should be reconsidered.

Non-Invasive Ultrasound Assessment of Endometrial Cancer Progression in Pax8-Directed Deletion of the Tumor Suppressors Arid1a and Pten in Mice.

Uterine cancers can be studied in mice due to the ease of handling and genetic manipulation in these models. However, these studies are often limited to assessing pathology post-mortem in animals euthanized at multiple time points in different cohorts, which increases the number of mice needed for a study. Imaging mice in longitudinal studies can track the progression of disease in individual animals, reducing the number of mice needed. Advances in ultrasound technology have allowed for the detection of micrometer-level changes in tissues. Ultrasound has been used to study follicle maturation in ovaries and xenograft growth but has not been applied to morphological changes in the mouse uterus. This protocol examines the juxtaposition of pathology with in vivo imaging comparisons in an induced endometrial cancer mouse model. The features observed by ultrasound were consistent with the degree of change seen by gross pathology and histology. Ultrasound was found to be highly predictive of the observed pathology, supporting the incorporation of ultrasonography into longitudinal studies of uterine diseases such as cancer in mice.

Effects of BAMBI on luteinized follicular granulosa cell proliferation and steroid hormone production in sheep.

Bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) regulates mammalian ovarian follicle growth and maturation; however, its effect on luteinized granulosa cells (LGCs) in sheep ovarian follicles remains unknown. Here we explored the regulatory role of LGC functions and steroid hormone synthesis by BAMBI. Multiple sequence alignment revealed that the sheep BAMBI gene sequence was relatively conserved. Sheep LGCs were strongly positive for BAMBI. LGC proliferation increased when BAMBI was silenced and decreased when BAMBI was overexpressed. After BAMBI overexpression, the expression of CASP3, CASP8, CASP9, and BAX significantly increased, whereas that of BCL2 and the ratio of BCL2/BAX expression decreased. The opposite was observed after BAMBI silencing. CDKN1A, CCND1, and CCND2 were downregulated with BAMBI overexpression and upregulated with BAMBI silencing. Expression of steroid hormone-related genes (CYP11A1, STAR, and 3BHSD), except CYP19A1, significantly increased after BAMBI overexpression. Moreover, estrogen and progesterone secretion increased after BAMBI overexpression and decreased after BAMBI interference. The effect of the exogenous addition of bone morphogenetic protein 2 (BMP2) on GCs was similar to that of BAMBI overexpression. In conclusion, BAMBI can regulate the proliferation and steroid hormone synthesis of sheep LGCs, and BMP2 can affect LGCs as an activator of BAMBI. These findings provide a basis for further research on the physiological role of BAMBI.

Regulation of human oocyte maturation in vivo during the final maturation of follicles.

Which substances and signal transduction pathways are potentially active downstream to the effect of FSH and LH in the regulation of human oocyte maturation in vivo? The regulation of human oocyte maturation appears to be a multifactorial process in which several different signal transduction pathways are active. Many studies in animal species have provided insight into the mechanisms that govern the final maturation of oocytes. Currently, these studies have identified several different mechanisms downstream to the effects of FSH and LH. Some of the identified mechanisms include the regulation of cAMP/cGMP levels in oocytes involving C-type natriuretic peptide (CNP), effects of epidermal growth factor (EGF)-related peptides such as amphiregulin (AREG) and/or epiregulin (EREG), effect of TGF-β family members including growth differentiation factor 9 (GDF9) and morphogenetic protein 15 (BMP15), activins/inhibins, follicular fluid meiosis activating sterol (FF-MAS), the growth factor midkine (MDK), and several others. However, to what extent these pathways and mechanisms are active in humans in vivo is unknown. This prospective cohort study included 50 women undergoing fertility treatment in a standard antagonist protocol at a university hospital affiliated fertility clinic in 2016-2018. We evaluated the substances and signalling pathways potentially affecting human oocyte maturation in follicular fluid (FF) and granulosa cells (GCs) collected at five time points during the final maturation of follicles. Using ELISA measurement and proteomic profiling of FF and whole genome gene expression in GC, the following substances and their signal transduction pathways were collectively evaluated: CNP, the EGF family, inhibin-A, inhibin-B, activins, FF-MAS, MDK, GDF9, and BMP15. All the evaluated substances and signal transduction pathways are potentially active in the regulation of human oocyte maturation in vivo except for GDF9/BMP15 signalling. In particular, AREG, inhibins, and MDK were significantly upregulated during the first 12-17 h after initiating the final maturation of follicles and were measured at significantly higher concentrations than previously reported. Additionally, the genes regulating FF-MAS synthesis and metabolism were significantly controlled in favour of accumulation during the first 12-17 h. In contrast, concentrations of CNP were low and did not change during the process of final maturation of follicles, and concentrations of GDF9 and BMP15 were much lower than reported in small antral follicles, suggesting a less pronounced influence from these substances. None. Although GC and cumulus cells have many similar features, it is a limitation of the current study that information for the corresponding cumulus cells is not available. However, we seldom recovered a cumulus-oocyte complex during the follicle aspiration from 0 to 32 h. Delineating the mechanisms governing the regulation of human oocyte maturation in vivo advances the possibility of developing a platform for IVM that, as for most other mammalian species, results in healthy offspring with good efficacy. Mimicking the intrafollicular conditions during oocyte maturation in vivo in small culture droplets during IVM may enhance oocyte nuclear and cytoplasmic maturation. The primary outlook for such a method is, in the context of fertility preservation, to augment the chances of achieving biological children after a cancer treatment by subjecting oocytes from small antral follicles to IVM. Provided that aspiration of oocytes from small antral follicles in vivo can be developed with good efficacy, IVM may be applied to infertile patients on a larger scale and can provide a cheap alternative to conventional IVF treatment with ovarian stimulation. Successful IVM has the potential to change current established techniques for infertility treatment. This research was supported by the University Hospital of Copenhagen, Rigshospitalet, the Independent Research Fund Denmark (grant number 0134-00448), and the Interregional EU-sponsored ReproUnion network. There are no conflicts of interest to be declared.

A note on biological data from the hunt of bowhead whales in West Greenland 2009–2011

One male and six female bowhead whales were taken for subsistence in Disko Bay, West Greenland, in April–May 2009–2011. All of these whales were sexually mature with body lengths exceeding 14m. One female was pregnant with a 3.87m foetus and three others presumably had small foetuses that were not detected in the field. Another female that showed no signs of recent pregnancy had a minimum of 7–8 corpora albicantia but no mature follicles. One 14.10m male with a 42kg testis was classified as sexually mature. Estimated ages of the whales were between 37 and 50 yrs. The observations on growth and reproduction were consistent with data on bowhead whales in Alaska. Four of the whales had recently been feeding as their stomachs contained calanoid copepods, especially Calanus hyperboreus.