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Objective: Understanding recruitment dynamics is necessary to predict population‐level responses to exploitation, management actions, or anthropogenic influences. Fecundity is commonly used as a metric of recruitment dynamics and can guide successful management of fisheries. However, an individual female's fecundity is not constant over time; females resorb ovarian follicles to regulate fecundity as they approach spawning. This suggests that sampling for fecundity too early may produce inaccurate estimates of relative fecundity. In Yellowstone National Park, suppression of invasive Lake Trout Salvelinus namaycush reduced the abundance of mature fish by 92% between 2012 and 2022. The continued efficacy of this suppression effort requires accurate assessments of reproductive potential of the population that remains. Methods: We sought to determine whether the timing of ovarian follicle collection affected estimates of mean relative fecundity. We collected ovarian follicles from female Lake Trout, which are autumn spawners, between mid‐August and early October in 2021 and 2022. The number of ovarian follicles per sample was counted to obtain estimates of relative fecundity for each female. Result: We observed a 13% decline in estimated mean relative fecundity between individuals that were sampled before mid‐September and those that were sampled after mid‐September. Conclusion: Our data support strategic timing of fecundity sampling to best capture the true reproductive capability of a population, which is a key metric used in models that guide adaptive management of fishes. Impact statementFemale Lake Trout undergo fecundity reduction through follicular atresia, reducing the number of ovarian follicles that may be spawned, which suggests that fecundity estimates based on fish that are sampled too early in the reproductive cycle will be inaccurate. [ABSTRACT FROM AUTHOR]

Here we report the case of a cow with two ovaries that each exhibited hyperplasia but that otherwise had normal gross morphology. Both ovaries had a large number of tertiary follicles on the ovarian surface. Oocytes from one ovary were studied in more detail. The transcriptome was largely similar to other oocytes. Oocytes could undergo cleavage at a rate consistent with other oocytes and result in blastocyst-stage embryo formation after in vitro maturation and fertilization. Review of the literature from cattle and other species did not reveal reports of a similar type of spontaneous ovarian abnormality. Whole genome sequencing revealed many single nucleotide polymorphisms with predicted large effects on protein structure that could potentially be causative for the phenotype. The variant considered most likely to cause the observed alteration in ovarian function was a mutation in the glycoprotein-modifying enzyme MAN1A2. [ABSTRACT FROM AUTHOR]

Although monotremes diverged from the therian mammal lineage approximately 187 million years ago, they retain various plesiomorphic and/or reptilian‐like anatomical and physiological characteristics. This study examined the morphology of juvenile and adult female reproductive tracts across various stages of the presumptive oestrous cycle, collected opportunistically from cadaver specimens submitted to wildlife hospitals during the breeding season. In adult females, ovaries had a convoluted cortex with follicles protruding from the ovarian surface. While protruding antral follicles were absent from the ovaries of juvenile echidnas, histological analysis identified early developing primordial and primary follicles embedded into the ovarian cortex. The infundibulum epithelial cells of the oviducts were secretory during the follicular phase but not at other stages, the ampulla region was secretory at all stages and is likely responsible for the mucoid layer deposited around the zona pellucida, and the isthmus region of the oviduct appeared to be responsible for initial deposition of the shell coat, as in marsupials. Female echidnas have two separate uteri, which never merge and enter separately into the urogenital sinus (UGS). This study confirmed that both uteri are functional and increase in glandular activity during the luteal phase. In the juvenile uteri, the endometrium was immature with minimal, small uterine glands. A muscular cervical region at the caudal extremity of each uterus, just before the cranial region of the UGS was defined by the absence of glandular tissue in all female echidnas, including the juveniles. There was no evidence of a definitive vaginal region. A clitoris was also detected that possessed a less developed but similar structural (homologous) anatomy to the male penis; urethral ducts while present did not appear to be patent. [ABSTRACT FROM AUTHOR]

Histological terminology of the female genital organs is currently a part of the internationally accepted nomenclature Terminologia Histologica (TH), the latest edition of which dates back to 2008. Many new discoveries have been documented within 16 years since then, and many discrepancies have been found. This paper aims to revise the terminology from clinical and educational perspectives comprehensively. The authors thoroughly searched the current edition of "Terminologia Histologica: International Terms for Human Cytology and Histology," focusing on missing and controversial terms in the chapter Female genital system. The authors identified six controversial and ambiguous terms and four missing important histological terms. The authors also discussed the addition of less used eponymic terms in the histological description of female genital organs like Hamperl cells, Popescu cells, Kroemer lacunae, Balbiani bodies, Call–Exner bodies, membrane of Slavianski, nabothian cysts, or anogenital sweat glands of van der Putte. We expect the second and revised edition of the TH to be published soon and hope that the Federative International Program on Anatomical Terminology will approve and incorporate all these propositions and suggestions. We also strongly recommend using the official internationally accepted Latin and English histological nomenclature—the TH, either in oral or written form, both in theoretical and clinical medicine. [ABSTRACT FROM AUTHOR]

Thyroid issues are common among women in their reproductive years, and women with thyroid dysfunction often encounter challenges with fertility. Arsenic is known for its toxic effects on the thyroid and ovaries, investigated independently. However, there is no known study directly or indirectly addressing the association between arsenic, thyroid function, and ovarian reserve. This study aims to investigate the effect of arsenic on thyroid function and its possible implications on ovarian follicular reserve. Female Balb/c mice were given sodium arsenite (0.2 ppm, 2 ppm, and 20 ppm) via drinking water for 30 days. Findings showed that arsenic decreased thyroid hormone levels (fT3 and fT4) while increasing TSH levels, which might have led to elevated levels of FSH and LH. Furthermore, arsenic treatment not only decreased thyroid follicle sizes but also altered the ovarian follicular count. The finding demonstrates that arsenic significantly reduced the expression of LAMP1, a lysosomal marker protein. This reduction leads to increased lysosomal permeability in the thyroid, resulting in a significant release of cathepsin B. These changes led to hypothyroidism, which might indirectly affect the ovaries. Also, the elevated levels of growth differentiation factor-8 in arsenic-treated ovaries indicate impaired folliculogenesis and ovulation. Furthermore, arsenic significantly increased the expressions of pAkt and pFoxo3a, implying that arsenic accelerated the activation of the primordial follicular pools. In conclusion, arsenic disrupts lysosomal stabilization, potentially leading to a decline in circulating fT3 and fT4 levels. This disturbance could, in turn, affect the estrous cycle and may alter the pattern of follicular development. [ABSTRACT FROM AUTHOR]

Fertility enhancement has been the subject of research for many years; more so due to the observed decline in fertility worldwide. Solanum macrocarpon has been widely acclaimed for its medicinal and antioxidant properties. However, its effects on fertility parameters have not been reported. This study evaluated the impact of ethanol leaf extract of S. macrocarpon (ELESM) on fertility parameters in female albino rats. Thirty (30) female rats of about 10 - 12 weeks of age were separated into six groups administered 0.5 ml of distilled water (placebo), 400mg/kg ELESM, 800mg/kg ELESM, 10 mg/kg cyclophosphamide (CP) + placebo, 10mg/kg CP + 400mg/kg ELESM, and 10mg/kg CP + 800mg/kg ELESM, respectively. After treatment (42 days), the females were mated with normal (untreated) adult male rats. The ELESM-treated rats exhibited significantly (p < 0.05) higher numbers of primary/secondary follicles, antral follicles and corpora lutea than the control groups. Cross-section of the ovaries of female rats showed normal histoarchitecture and healthy follicles at various developmental stages in the control and ELESMtreated rats, as well as improvement in histoarchitecture of CP + ELESM rats, compared with the CP + placebo group. Although the ELESM-treated animals had slightly higher fertility index, there was no statistical difference (p > 0.05) between their live foetal numbers, mean foetus weights, mean foetal crown-rump lengths, number of resorbed embryos, and fertility index compared with those of the normal control. The findings suggest the pro-fertility effects of the extract in female rats and the potential to ameliorate cyclophosphamide-induced gonadal toxicity. [ABSTRACT FROM AUTHOR]

Abstract Background Saidi sheep are the most abundant ruminant livestock species in Upper Egypt, especially in the Assiut governorate. Sheep are one of the most abundant animals raised for food in Egypt. They can convert low-quality roughages into meat and milk in addition to producing fiber and hides therefore; great opportunity exists to enhance their reproduction. Saidi breed is poorly known in terms of reproduction. So this work was done to give more information on some hormonal, oxidative, and blood metabolites parameters in addition to histological, histochemical and immunohistochemical investigations of the ovary during follicular phase of estrous cycle. The present study was conducted on 25 healthy Saidi ewes for serum analysis and 10 healthy ewes for histological assessment aged 2 to 5 years and weighted (38.5 ± 2.03 kg). Results The follicular phase of estrous cycle in Saidi sheep was characterized by the presence of ovarian follicles in different stages of development and atresia in addition to regressed corpus luteum. Interestingly, apoptosis and tissue oxidative markers play a crucial role in follicular and corpus luteum regression. The most prominent features of the follicular phase were the presence of mature antral (Graafian) and preovulatory follicles as well as increased level of some blood metabolites and oxidative markers. Here we give a new schematic sequence of ovarian follicles in Saidi sheep and describing the features of different types. We also clarified that these histological pictures of the ovary was influenced by hormonal, oxidative and blood metabolites factors that characterizes the follicular phase of estrous cycle in Saidi sheep. Conclusion This work helps to understanding the reproduction in Saidi sheep which assist in improving the reproductive outcome of this breed of sheep. These findings are increasingly important for implementation of a genetic improvement program and utilizing the advanced reproductive techniques as estrous synchronization, artificial insemination and embryo transfer.

We investigated the association between air pollution and changes in ovarian follicles, anti-mullerian hormone (AMH) levels, the occurrence of necroptosis cell death by activation of receptor-interacting protein kinase 3 (RIPK3) and, the activation of mixed lineage kinase domain-like (MLKL) proteins. Forty-two female Wistar rats were divided into three groups of 14 each, which were exposed to real-ambient air, filtered air and purified air (control) in two periods of 3 and 5 months. The results showed that the number of ovarian follicles decreased in the group exposed to real-ambient air versus the control group (P < 0.0001). The trend of age-related AMH changes with respect to exposure to air pollutants was affected and its levels decreased after 3 months of exposure. The MLKL increased in the group exposed to the real-ambient air compared to the control group (P = 0.033). Apparently long-term exposure to air pollution can reduce ovarian reserves. [ABSTRACT FROM AUTHOR]

Background: Saidi sheep are the most abundant ruminant livestock species in Upper Egypt, especially in the Assiut governorate. Sheep are one of the most abundant animals raised for food in Egypt. They can convert low-quality roughages into meat and milk in addition to producing fiber and hides therefore; great opportunity exists to enhance their reproduction. Saidi breed is poorly known in terms of reproduction. So this work was done to give more information on some hormonal, oxidative, and blood metabolites parameters in addition to histological, histochemical and immunohistochemical investigations of the ovary during follicular phase of estrous cycle. The present study was conducted on 25 healthy Saidi ewes for serum analysis and 10 healthy ewes for histological assessment aged 2 to 5 years and weighted (38.5 ± 2.03 kg). Results: The follicular phase of estrous cycle in Saidi sheep was characterized by the presence of ovarian follicles in different stages of development and atresia in addition to regressed corpus luteum. Interestingly, apoptosis and tissue oxidative markers play a crucial role in follicular and corpus luteum regression. The most prominent features of the follicular phase were the presence of mature antral (Graafian) and preovulatory follicles as well as increased level of some blood metabolites and oxidative markers. Here we give a new schematic sequence of ovarian follicles in Saidi sheep and describing the features of different types. We also clarified that these histological pictures of the ovary was influenced by hormonal, oxidative and blood metabolites factors that characterizes the follicular phase of estrous cycle in Saidi sheep. Conclusion: This work helps to understanding the reproduction in Saidi sheep which assist in improving the reproductive outcome of this breed of sheep. These findings are increasingly important for implementation of a genetic improvement program and utilizing the advanced reproductive techniques as estrous synchronization, artificial insemination and embryo transfer. [ABSTRACT FROM AUTHOR]

Having one's life threatened by a disease like ovarian cancer is the single most crucial thing in the whole world. It is difficult to achieve high performance without sacrificing computational efficiency; the results of the denoising process are not as good as they could be; the proposed models are nonconvex and involve several manually chosen parameters, which provides some leeway to boost denoising performance; the methods generally involve a complex optimisation problem in the testing stage; Here at DnCNN, we've developed our own version of the deep ii learning model, a discriminative learning technique. The goal was to eliminate the need for the iterative optimisation technique at the time it was being evaluated. The goal was to avoid having to go through testing altogether, thus this was done. It is highly advised to use a Deep CNN model, the efficacy of which can be evaluated by comparing it to that of more traditional filters and pre-trained DnCNN. The Deep CNN strategy has been shown to be the best solution to minimise noise when an image is destroyed by Gaussian or speckle noise with known or unknown noise levels. This is because Deep CNN uses convolutional neural networks, which are trained using data. This is because convolutional neural networks, which are the foundation of Deep CNN, are designed to learn from data and then use that learning to make predictions. Deep CNN achieves a 98.45% accuracy rate during testing, with an error rate of just 0.002%. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of vitamin A injection on reproductive performance in repeat breeder cows. One hundred and sixty-two multiparous Holstein cows with at least three consecutive unsuccessful inseminations were randomly assigned to experimental treatments. Treatments included (1) control: twice intramuscular injection 10 ml placebo30 days apart: 0.9% sodium chloride (n=87) and (2) vitamin A: twice intramuscular injection 10 ml retinol palmitate 30 days apart (n=75). Animals submitted to double-ovsynch protocol and received their experimental treatments on the tenth day of the protocol (the day of the second injection of GnRH). The injection of retinol palmitate significantly increased the number of ovarian follicles larger than 10 mm compared to the control (P <0.05). Plasma concentration of superoxide dismutase enzyme tended to increase (P = 0.09) and malondialdehyde concentration tended to decrease (P = 0.08) under the influence of vitamin A injection. The conception rate at first artificial insemination was 25.29% and 34.66% for control and vitamin A treatments respectively, this difference was not significant (P = 0.19). The odds ratio of conception in the first service for vitamin A treatment was 1.57 times higher than the control treatment but was not statistically significant (P = 0.19). In conclusion, vitamin A injection improved antioxidant function and ovarian function. The reproductive performance improved, although not statistically significant. [ABSTRACT FROM AUTHOR]

Eighteen 5 months old veiled chameleon females (Chamaeleo calyptratus) were used in the study. Seven females received subcutaneous implants with gonadotropin-releasing hormone agonist (GnRH) deslorelin acetate whereas eleven females were used as control animals without any implants. Females were kept in five terraria, in groups of four females (in 3 terraria) and groups of three females (in 2 terraria), respectively. A minimum of one female with GnRH implants was present in each terrarium. They were kept under standard husbandry conditions. Females of both groups (females with GnRH and controls, respectively) were monitored for three years. No differences between females with GnRH implants and females without GnRH implants were observed with respect to the presence of large ovarian follicles, number of eggs/female, or number of clutches/female. GnRH implants did not prevent spontaneous reproductive activity in any of the 7 females with implants. Ovariectomy was performed in 8 females (4 females with GnRH implants and 4 control females). Ten females (3 females with GnRH implants and 7 control females) had to be euthanised. In 17 of 18 female veiled chameleons of this study histologic examination revealed heterophilic granulomatous oophoritis. The use of GnRH agonist implants did not prove to be an appropriate method for the control of reproductive function in captive female veiled chameleons.

Abstract Background Over the past two decades, increasing number of people with cystic fibrosis (CF) survive into adulthood. Compared to the general population, sub-fertility is an obstacle for many women with CF (wwCF). Decreased ovarian reserve has been proposed as a possible cause, but limited data is available to support this. The aim of this study was to evaluate the ovarian reserve in wwCF and to correlate this with patients’ demographic and clinical data. Methods Reproductive-aged wwCF were enrolled during their routine medical appointments. Assessment included Anti-Mullerian hormone (AMH) levels, routine blood tests and antral follicular count (AFC) evaluation. Additionally, demographic, and clinical information were collected. Results A total of wenty-three wwCF were enrolled, with ages ranging from 19 to 40 years (median 27 years). Among the fourteen wwCF who were considering pregnancy, five (35.7%) disclosed undergoing an infertility assessment and receiving fertility treatments. All but one patient had an Anti-Mullerian hormone (AMH) level between the 5th and 95th % for age. Measurement of the antral follicular count (AFC) was possible in 12 of the 23 patients and was ranging 8–40 with a median of 17. The proportion of wwCF presenting below median AMH values was not different in sub-fertile as compared to fertile wwCF (P value 0.54). There were no correlations between AMH levels and disease severity parameters. AMH seemed to be relatively higher in wwCF with mild class mutations, but this was not shown to have statistical significance. Conclusions Our results, in contrast with the limited available published data, do not support the hypothesis that decreased ovarian reserve plays a major role in infertility in wwCF.

Simple Summary: Reproduction is a pivotal physiological process in various biological organisms. As the zebrafish has been suggested as a model for the study of numerous aspects of ovarian development, this research aimed to pinpoint the cellular and microenvironmental changes of the ovary in zebrafish during the spawning season, in addition to providing information on the ovarian expression of Sox9 and myostatin. Various stages of oogenesis were described. Furthermore, immunohistochemical analysis revealed SOX9 and myostatin expression in primary and pre-vitellogenic oocytes and the theca cell layers. Moreover, a wide diversity of cells was detected in the ovarian stroma. Collectively, the findings of this study support the importance of the zebrafish ovary as a model for follicular development studies. This study sought to examine the ovarian cellular and stromal components of the zebrafish (Danio rerio) throughout the spawning season using light and electron microscopic tools. The ovaries of zebrafish showed oocytes in all stages of follicular development and degeneration (atresia). Six stages of oogenesis were demonstrated: oogonia, early oocytes, late oocytes, vacuolated follicles, the yolk globule stage (vitellogenesis), and mature follicles. The SOX9 protein was expressed in the ooplasm of the primary and previtellogenic oocytes and the theca cell layer of the mature follicles. Myostatin was expressed in the granulosa and theca cells. Many stem cells in the ovarian stroma expressed myostatin and SOX9. During the spawning season, the EM results indicated that the zona radiata increased in thickness and was crossed perpendicularly by pore canals that contained processes from both oocytes and zona granulosa. The granulosa cells contained many mitochondria, rER, sER, and vesicles. Meanwhile, the thecal layer consisted of fibroblast-like cells. Atretic follicles could be demonstrated that involved both oocytes and their follicular walls. Several types of cells were distinguished in the ovarian stroma, including mast cells, telocytes, lymphocytes, fibroblasts, endocrine cells, macrophages, adipocytes, dendritic cells, and steroidogenic (stromal) cells. The ovary of the zebrafish serves as a model to investigate follicular development. [ABSTRACT FROM AUTHOR]

In the current study, efficacy of GnRH, hCG and seminal plasma for the induction of ovulation in dromedary camels during breeding season was investigated. Sixteen female dromedary camels, having ovarian follicle size of 12-19mm, were randomly divided into four equal groups G, H, SP and C. The camels in groups G and H were injected with 2ml (50µg) GnRH analogue and 3000IU of hCG, respectively. Camels in group SP were injected with 1ml seminal plasma mixed with 1ml normal saline and group C (control group) was injected with 1ml normal saline intramuscularly. For the confirmation of ovulation, and CL development, ovaries of experimental camels were examined through trans-rectal ultrasonography on days 1, 2, 3, 8 and 11 post-treatment. The Progesterone ELISA kit was used to determine serum progesterone (P4) concentrations in samples collected on days 0, 3, 6, 8, and 11 of treatment. The results revealed that ovulation rates were 75, 50, 50 and 0% in groups G, H, SP and C, respectively, values for G, H and SP groups were higher compared to group C (p<0.05), while former three groups differed non-significantly from one another. Serum P4 concentrations were <0.5ng/ml in camels of all groups on day 0. However, among ovulated camels, the serum P4 concentration was highest on day 8, when it was 4.80±0.15, 4.15±0.14 and 2.67±0.15ng/ml in SP, H and G groups, respectively; the difference among 3 groups was significant (p<0.05). It was concluded that in dromedary females, use of hormones for the induction of ovulations is an effective option and can safely be used in camel breeding programs, as hormones are easily available compared to seminal plasma. [ABSTRACT FROM AUTHOR]

The effects of calcitriol (CT) and/or fish oil (FO) on performance, oviposition time, sex ratio and morphology of the reproductive system of laying Chukar partridges were studied. Female (n = 48) and male (n = 16) partridges were used in a completely randomised design using a 2 × 2 factorial arrangement and were randomly allocated to either of four experimental treatments with four cage replicates of three females and one male each. Female birds received no FO (CON − FO) or were orally administered with 0.2 mL (0.24 g)/500 g body weight FO (CON + FO) or 0.2 mL solution containing 10 µg CT (CT − FO), or their combination (CT + FO) for 42 successive days. The eggs were collected every two hours between 07:00 and 23:00 h. Administering FO along with CT had considerably increasing effect on the male‐biased sex ratio. FO and CT administration interacted to increase serum calcium concentration. Experimental treatments increased the number of leucocytes and erythrocytes. Serum cholesterol was decreased in CON + FO partridges compared with those of the CT − FO and CON − FO birds. There was an interaction between FO and CT on the weight of eggs and hatchlings, number of medium white follicles, diameter and the number of small yellow follicles, the weight and diameter of the fifth follicles (F5), and thickness of secondary mucosal folds in both uterus and vagina. Administering CT alone or with FO increased the feed intake, egg production, oviductal weight, diameter and number of large yellow follicles, the weight and diameter of the second (F2) and first (F1) follicles compared with those of the CON – FO females. Further studies are required to elucidate the mechanisms by which such changes in the sex ratio skew, ovary and oviduct are mediated. [ABSTRACT FROM AUTHOR]

Angiopoietin-2 (Ang-2) is a local ovarian growth factor belonging to the angiopoietin/Tie (tyrosine kinase with Ig and EGF homology domains) signalling pathway, one of the main pathways involved in ovarian follicular angiogenesis. The main objective of this study is to assess the differential protein expression of Ang-2 in the developmental phases of ovarian follicles of crossbred Malabari goats employing an immunohistochemical technique. Ang-2 protein expression was found in all developmental phases of ovarian follicles, including primordial, primary, small, and large antral ovarian follicles. Ang-2 was found in the granulosa cells, theca interna cells, follicular fluid (granulosa cells in the FF), endothelial cells of capillaries and germinal epithelium of the goat ovaries. The Quantitative Method-Percentage Positivity of Ang-2 expression revealed that it was higher in the initial stages of ovarian follicular development and decreased with later stages of follicular development in cross-bred Malabari goats. Moreover, the protein expression of Ang2 was found to be higher in granulosa cells (GC) than in theca interna (TI) cells of antral follicles as evident from the higher staining intensity in GC cells compared to TI cells. It is therefore concluded that the Ang-2 protein expression in ovarian follicular cells decreased with an increase in follicle size and development and based on the combined scores for immunostaining (staining intensity and the number of positive staining cells), the Ang-2 was found to be expressed more in the granulosa cell layer compared to the theca interna cells of the antral follicle in crossbred Malabari goats.

Abstract Specimens of Cnemidocarpa amphora were collected monthly from the Arabian Gulf from September 2017 to August 2018. Parts of their gonads were prepared for histological testing. The gonads’ diameters varied by month. Each gonad contained many ovarian follicles with different morphologies and was surrounded by several testicular follicles. The ovarian and testicular follicles were separate, although the latter were always present near the former. Repeated measures ANOVA tests were conducted to investigate monthly changes in oocyte stages. In squirts measuring 12–13 cm in length, the gonads measured 30–50 mm from July to August; 20–25 mm from September to October; 15–20 mm from November to February; and 25–40 mm from March to June. Oogonia budded from the germinal epithelium with diameters of 20–30 µm. Previtellogenic oocytes measuring 70–120 µm were characterized by the deposition of small granules of protein around the nucleus, a continuous layer of follicular cuboidal epithelium, and scattered vacuoles in the ooplasm. The measurement of gonads and oocyte diameters were performed by image analysis (Image scope 2.3, Image Line, Inc.) and stage micrometer. The vitellogenic oocytes measured 130–220 µm and the follicular epithelium consisted of flattened and cuboidal layers. Beneath the vitelline membrane, scattered test cells appeared in the ooplasm and different granules of protein and MPS were deposited in the ooplasm. In the later phase, lipid droplets began to appear in the ooplasm. Yolk bodies formed after the impregnation of various granules together and the oocyte was ready to be shed. Before spawning, a yolk membrane appeared above the ooplasm. Post-vitellogenic oocytes, in which the homogeneity of ooplasm was restored, underwent gradual lysis and entered the atretic phase. Different stages of sperm development were present year-round in different follicles of the same squirt; hence, the testes were always mature.

Background: Over the past two decades, increasing number of people with cystic fibrosis (CF) survive into adulthood. Compared to the general population, sub-fertility is an obstacle for many women with CF (wwCF). Decreased ovarian reserve has been proposed as a possible cause, but limited data is available to support this. The aim of this study was to evaluate the ovarian reserve in wwCF and to correlate this with patients' demographic and clinical data. Methods: Reproductive-aged wwCF were enrolled during their routine medical appointments. Assessment included Anti-Mullerian hormone (AMH) levels, routine blood tests and antral follicular count (AFC) evaluation. Additionally, demographic, and clinical information were collected. Results: A total of wenty-three wwCF were enrolled, with ages ranging from 19 to 40 years (median 27 years). Among the fourteen wwCF who were considering pregnancy, five (35.7%) disclosed undergoing an infertility assessment and receiving fertility treatments. All but one patient had an Anti-Mullerian hormone (AMH) level between the 5th and 95th % for age. Measurement of the antral follicular count (AFC) was possible in 12 of the 23 patients and was ranging 8–40 with a median of 17. The proportion of wwCF presenting below median AMH values was not different in sub-fertile as compared to fertile wwCF (P value 0.54). There were no correlations between AMH levels and disease severity parameters. AMH seemed to be relatively higher in wwCF with mild class mutations, but this was not shown to have statistical significance. Conclusions: Our results, in contrast with the limited available published data, do not support the hypothesis that decreased ovarian reserve plays a major role in infertility in wwCF. [ABSTRACT FROM AUTHOR]

Eighteen 5 months old veiled chameleon females (Chamaeleo calyptratus) were used in the study. Seven females received subcutaneous implants with gonadotropin-releasing hormone agonist (GnRH) deslorelin acetate whereas eleven females were used as control animals without any implants. Females were kept in five terraria, in groups of four females (in 3 terraria) and groups of three females (in 2 terraria), respectively. A minimum of one female with GnRH implants was present in each terrarium. They were kept under standard husbandry conditions. Females of both groups (females with GnRH and controls, respectively) were monitored for three years. No dif)ferences between females with GnRH implants and females without GnRH implants were observed with respect to the presence of large ovarian follicles, number of eggs/female, or number of clutches/female. GnRH implants did not prevent spontaneous reproductive activity in any of the 7 females with implants. Ovariectomy was per)formed in 8 females (4 females with GnRH implants and 4 control females). Ten females (3 females with GnRH implants and 7 control females) had to be euthanised. In 17 of 18 female veiled chameleons of this study histologic examination revealed heterophilic granulomatous oophoritis. The use of GnRH agonist implants did not prove to be an appropriate method for the control of reproductive function in captive female veiled chameleons. [ABSTRACT FROM AUTHOR]

Objective: To investigate the role of vascular endothelial growth factor (VEGF)165a, VEGF165b, and VEGF receptor (VEGFR) in the development of bovine follicles. Methods: We cultured follicular cells that were collected from small, medium, and large sized bovine follicles with estrogen and measured the expression of VEGF, VEGFR2 and VEGF165b by Western blot analysis and immunofluorescence. Results: The expression of VEGF165 increased in all follicle sizes and the expression of VEGF165b was increased in the small and large follicles after culturing in an estrogen containing medium. The expression of VEGFR2 was increased in the medium and large follicles after culturing with estrogen for 96 h. VEGF165 was activated at 100 ng/mL estrogen in the large follicles for 96 h. In addition, VEGFR2 was upregulated in the medium and large follicles after treated with 100 ng/mL estrogen for 96 h. Conclusions: This evidence suggests that the expression of VEGF165 and VEGFR is associated with estrogen stimulation during the development of bovine follicles and in an autocrine or paracrine manner. This reveals an advantage during oocyte maturation in vitro.

Objective: To examine the effect of quercetin on stereological parameters and autophagy-related genes in ovaries of polycystic ovary syndrome (PCOS) rats. Methods: Fifty female Sprague-Dawley rats were randomly divided into five groups: the control group, the ethanol group, the quercetin group (15 mg/kg/day), the PCOS group, as well as the PCOS + quercetin group. After the induction of PCOS, quercetin was administered orally for 30 days. Histological, stereological and real-time PCR analyses were carried out to evaluate the effect of quercetin on PCOS rats. Results: Stereological analysis revealed that quercetin significantly increased the number of ovarian follicles and the volume of corpus luteum and induced a significant decrease in atretic follicles in comparison to the PCOS group. In addition, quercetin markedly increased mTOR gene expression while decreasing Beclin-1 and LC3 gene expression. Conclusions: Quercetin strongly modulates the expression of ovarian autophagy-related genes and stereological parameters in PCOS rats. Therefore, it can be considered as an ameliorative component for ovarian follicular impairments.

Purpose: It is unknown if future fertility is compromised by the administration of chemotherapy during pregnancy. The aim of this study was to identify if chemotherapy affects the maternal ovaries during pregnancy and whether these effects depend on type of chemotherapy and duration of exposure. Methods: Pregnant 8-week-old female BL6 mice were exposed to 6 different single chemotherapeutic agents (carboplatin, cisplatin, paclitaxel, epirubicin, doxorubicin, or cyclophosphamide) or saline at gestational day (GD) 13.5. The mice were sacrificed at GD 15.5 or GD 18.5. Ovaries were assessed by histopathology and immunohistochemistry. Follicle count was determined per follicle stage and per treatment modality. Results: Maternal ovarian damage was demonstrated by the presence of apoptosis and necrosis in preantral follicles. The extent of this damage depends upon type of chemotherapy and duration of exposure (2 or 5 days). After short exposure, 81% of ovaries showed histopathologic signs of damage compared to 36% after long exposure, which might suggest a transient effect. Loss of primordial follicles (PMFs) was observed after both short and long exposure, with a reduction of more than 70%. Evidence of DNA damage, as demonstrated by phospho-H2AX expression, was present in 23% (range 0–89%) of PMFs exposed to chemotherapy, but only in the short exposure group. Overall, the least damage was seen after administration of paclitaxel. Conclusion: Despite physiological ovarian function suppression during gestation, chemotherapy-induced damage of the ovaries occurs in pregnant mouse models, potentially affecting future fertility. [ABSTRACT FROM AUTHOR]

With increasing technological developments, exposure to non-ionizing radiations has become unavoidable as people cannot escape from electromagnetic field sources, such as Wi-Fi, electric wires, microwave oven, radio, telecommunication, bluetooth devices, etc. These radiations can be associated with increased health problems of the users. This review aims to determine the effects of non-ionizing electromagnetic radiations on female fertility. To date, several in vitro and in vivo studies unveiled that exposure to non-ionizing radiations brings about harmful effects on oocytes, ovarian follicles, endometrial tissue, estrous cycle, reproductive endocrine hormones, developing embryo, and fetal development in animal models. Non-ionizing radiation also upsurges the free radical load in the uterus and ovary, which leads to inhibition of cell growth and DNA disruptions. In conclusion, non-ionizing electromagnetic radiations can cause alterations in both germ cells as well as in their nourishing environment and also affect other female reproductive parameters that might lead to infertility. [ABSTRACT FROM AUTHOR]

Imidacloprid is a neonicotinoid pesticide used in large-scale agricultural systems, home gardens, and veterinary pharmaceuticals. Imidacloprid is a small molecule that is more water-soluble than other insecticides, increasing the likelihood of large-scale environmental accumulation and chronic exposure of non-targeted species. Imidacloprid can be converted to the bioactive metabolite desnitro-imidacloprid in the environment and body. Little is known about the mechanisms by which imidacloprid and desnitro-imidacloprid induce ovarian toxicity. Thus, we tested the hypothesis that imidacloprid and desnitro-imidacloprid differentially affect antral follicle growth and steroidogenesis in vitro. Antral follicles were dissected from the ovaries of CD-1 mice and cultured in media containing vehicle control or 0.2 µg/mL–200 µg/mL of imidacloprid or desnitro-imidacloprid for 96 h. Follicle morphology was monitored, and follicle size was measured every 24 h. At the end of the culture periods, media were used to quantify follicular hormone levels, and follicles were used for gene expression analysis of steroidogenic regulators, hormone receptors, and apoptotic factors. Imidacloprid did not affect follicle growth or morphology compared to the control. Desnitro-imidacloprid inhibited follicle growth and caused follicles to rupture in culture compared to the control. Imidacloprid increased progesterone, whereas desnitro-imidacloprid decreased testosterone and progesterone compared to the control. Desnitro-imidacloprid also changed estradiol compared to the control. At 48 h, IMI decreased the expression of Star, Cyp17a1, Hsd17b1, Cyp19a1, and Esr2 and increased the expression of Cyp11a1, Cyp19a1, Bax, and Bcl2 compared to the control. IMI also changed the expression of Esr1 compared to the control. At 48 h, DNI decreased the expression of Cyp11a1, Cyp17a1, Hsd3b1, Cyp19a1, and Esr1 and increased the expression of Cyp11a1, Hsd3b1, and Bax compared to the control. At 72 h of culture, IMI significantly decreased the expression of Cyp19a1 and increased the expression of Star and Hsd17b1 compared to the control. At 72 h, DNI significantly decreased the expression of Cyp11a1, Cyp17a1, Hsd3b1, and Bax and increased the expression of Esr1 and Esr2. At 96 h, IMI decreased the expression of Hsd3b1, Cyp19a1, Esr1, Bax, and Bcl2 compared to the control. At 96 h, DNI decreased the expression of Cyp17a1, Bax, and Bcl2 and increased the expression of Cyp11a1, Hsd3b1, and Bax compared to the control. Together, these data suggest mouse antral follicles are targets of neonicotinoid toxicity, and the mechanisms of toxicity differ between parent compounds and metabolites. [ABSTRACT FROM AUTHOR]

Summary: The goal of this study was to determine the distribution of preantral follicles in bovine ovaries. Follicular distribution in the ovaries (n = 12) was evaluated in the region of the greater curvature of the ovary (GCO) and the region close to the ovarian pedicle (OP) of Bos taurus indicus heifers of the Nelore breed. Two fragments were obtained from each region of the ovary (GCO and OP). The mean weight of the ovaries was 4.04 ± 0.32 g. The mean antral follicle count (AFC) was 54.58 ± 3.55 follicles (minimum and maximum variation of 30 and 71 follicles, respectively). In total, 1123 follicles were visualized in the region of the GCO; 949 (84.5%) of them were primordial follicles and 174 (15.5%) were developing follicles. The region close to the OP contained 1454 follicles, of which 1266 (87%) were primordial follicles and 44 (12.9%) were developing follicles. The OP region showed a higher proportion of intact follicles in the primordial (P < 0.0001) and primary (P = 0.042) stages compared with the GCO region. The proportion of secondary follicles was similar in the OP and GCO regions. The ovaries of two bovine females (16%; 2/12) contained multi-oocytes follicles, which were characterized as primary follicles. Therefore, the distribution of preantral follicles in the bovine ovary was heterogeneous, with the region close to the OP containing a greater number of preantral follicles compared with the GCO region (P < 0.05). [ABSTRACT FROM AUTHOR]

This study aimed to investigate the efficacy of emptied ovarian follicles of sheep as a container for cryopreservation of human spermatozoa to preserve the presence of low concentrations of spermatozoa at the post-thawing stage. This research was performed on 30 semen samples from oligozoospermic patients and 10 samples from normozoospermic males. They were diagnosed according to the standard criteria of the World Health Organization 2010. Semen samples were classified into four groups of G1-G4 according to sperm concentration: 3-5 million/mL, 6-10 million/mL, 11-15 million/mL, and 16-20 million/mL, respectively. Each sample was divided into two equal parts. One part was cryopreserved without cryoprotectant, while the other was diluted 1:1 with 10% glycerol-based cryosolution. The ovarian follicles of sheep were obtained from a local slaughterhouse and prepared by slicing the ovaries and evacuating the follicular fluid and oocyte. The emptied follicles were injected with the prepared semen samples. After cryopreservation and thawing, the semen mixture aspired outside the follicles, and sperm parameters were measured, namely concentration, progressive motility, total motility, and normal morphology. Sperm concentration and progressive and total sperm motility were significantly (P<0.01) decreased in all groups at the post-thawing stage, compared to the pre-freezing stage. The sperm concentration was significantly higher (P<0.01) in samples cryopreserved without cryoprotectant, compared to that in those cryopreserved with glycerol. However, progressive and total motility were significantly (P<0.01) higher in samples cryopreserved with glycerol, compared to that in the samples cryopreserved without cryoprotectant in all groups. Moreover, no significant difference was found between the pre-freezing and post-thawing stages in terms of normal morphology. Emptied ovarian follicles are an appropriate carrier for cryopreservation of human sperms, especially for patients with oligozoospermia. The best sperm survival rate in this technique was observed when using glycerol-based cryosolution. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are endocrine-disrupting chemicals that mimic estrogen in fish. Among the various PCBs, 3,3’,4,4’,5-pentachlorobiphenyl (PCB126), considered an estrogen antagonist, has been reported to elicit estrogenic activity in fish. We investigated the estrogenic potency of PCB126 in in vitro oocyte maturation in dusky tripletooth goby, Tridentiger obscurus. In this study, we quantified steroid metabolites following exposure to PCB126 and estradiol-17β (E2). Vitellogenic ovarian follicles were incubated, in vitro, with 10 and 100 ng/mL PCB126 or E2 with [3H]17α-hydroxyprogesterone as a precursor. Testosterone (T) and E2, were identified using thin-layer chromatography, high-performance liquid chromatography, and gas chromatography-mass spectrometry. Both PCB126 and E2 increased T and E2 metabolite production. Further, vitellogenic ovarian follicles were exposed to PCB126 (1, 10 and 100 ng/mL) or E2 (0.01, 0.1 and 1 ng/mL) in vitro, and T and E2 from the incubation media were measured. PCB126 (100 ng/mL) inhibited T production and increased E2 production. Furthermore, we investigated the effects of PCB126 on the final oocyte maturation process. Germinal vesicle migration ovarian follicles were in vitro incubated with 0.1, 1, 10 and 100 ng/mL of PCB126 or E2. High doses of PCB126 (10 and 100 ng/mL) inhibited germinal vesicle breakdown. These results suggest that PCB126 has an estrogenic potency in oocyte maturation in T. obscurus.

Objective: To examine the effect of quercetin on stereological parameters and autophagy-related genes in ovaries of polycystic ovary syndrome (PCOS) rats. Methods: Fifty female Sprague-Dawley rats were randomly divided into five groups: the control group, the ethanol group, the quercetin group (15 mg/kg/day), the PCOS group, as well as the PCOS + quercetin group. After the induction of PCOS, quercetin was administered orally for 30 days. Histological, stereological and real-time PCR analyses were carried out to evaluate the effect of quercetin on PCOS rats. Results: Stereological analysis revealed that quercetin significantly increased the number of ovarian follicles and the volume of corpus luteum and induced a significant decrease in atretic follicles in comparison to the PCOS group. In addition, quercetin markedly increased mTOR gene expression while decreasing Beclin-1 and LC3 gene expression. Conclusions: Quercetin strongly modulates the expression of ovarian autophagy-related genes and stereological parameters in PCOS rats. Therefore, it can be considered as an ameliorative component for ovarian follicular impairments. [ABSTRACT FROM AUTHOR]

Angiopoietin-2 (Ang-2) is a local ovarian growth factor belonging to the angiopoietin/Tie (tyrosine kinase with Ig and EGF homology domains) signalling pathway, one of the main pathways involved in ovarian follicular angiogenesis. The main objective of this study is to assess the differential protein expression of Ang-2 in the developmental phases of ovarian follicles of crossbred Malabari goats employing an immunohistochemical technique. Ang-2 protein expression was found in all developmental phases of ovarian follicles, including primordial, primary, small, and large antral ovarian follicles. Ang-2 was found in the granulosa cells, theca interna cells, follicular fluid (granulosa cells in the FF), endothelial cells of capillaries and germinal epithelium of the goat ovaries. The Quantitative Method-Percentage Positivity of Ang-2 expression revealed that it was higher in the initial stages of ovarian follicular development and decreased with later stages of follicular development in cross-bred Malabari goats. Moreover, the protein expression of Ang2 was found to be higher in granulosa cells (GC) than in theca interna (TI) cells of antral follicles as evident from the higher staining intensity in GC cells compared to TI cells. It is therefore concluded that the Ang-2 protein expression in ovarian follicular cells decreased with an increase in follicle size and development and based on the combined scores for immunostaining (staining intensity and the number of positive staining cells), the Ang-2 was found to be expressed more in the granulosa cell layer compared to the theca interna cells of the antral follicle in crossbred Malabari goats. [ABSTRACT FROM AUTHOR]

In this paper, we present a new way to assess the concentration of estradiol (E2) and Insulin Growth Factor-1 (IGF) based on the results from ultrasound scans combined with mathematical models. The IGF1 model is based on the progesterone (P4) concentration, which can be estimated with models calculating P4 level based on the size/volume of corpus luteum (CL) measured during ultrasound scans. At this moment little is known about the underlying reasons for double ovulation and silent heat occurrences. Both of these are linked to the level of IGF1: double ovulations are linked to higher IGF1 levels and and silent heat is linked to lower E2 to P4 ratio. These models can help to improve understanding of the related concentrations of E2 and IGF1. Currently, it is known that diet and genetic factors have an impact on ovulation rates and silent heat. In this study, we also examine the decline of the production of E2 in vivo by atretic follicles throughout the process of atresia. This is the first recorded quantitative description of this decline. [ABSTRACT FROM AUTHOR]

Abstract Objectives Methionine is known as an essential amino acid in mammals. Consuming excessive amounts of methionine has toxic effects. This study aimed at evaluating the histomorphometric and histopathologic changes of ovaries after methionine administration during follicle formation. Material and methods A total of 60 newborn female rats born under similar conditions were selected and randomly assigned into three groups including control, recipients of 50 and 200 mg/kg body weight of methionine for 5 days. On day 120, all 60 female rats were euthanized and the whole left ovary of each animal was taken in order to count the number of primordial, primary, secondary, antral, atretic follicles, as well as corpora lutea and also to conduct histopathologic study. Results According to the results, the 50 mg/kg methionine did not significantly change the number of primordial follicles compared to the control group but the 200 mg/kg dose significantly decreased the number of primordial follicles. There were no significant differences between the groups in the number of other types of follicles and also in the number of corpora lutea. There was no histopathological lesion in the groups. Conclusions It seems that the high dose of methionine could exacerbate apoptosis of the primordial ovarian follicle during the follicle assembly process. However, the remaining were enough to form later stages of follicles after puberty.

The present study investigated the effect of adding allopathic doxorubicin (DOX 0.3 µg/mL), the vehicle of ultradiluted/dynamized doxorubicin (0.2 % ethanol), different dynamizations of ultradiluted/dynamized doxorubicin (DOX 6CH, DOX 12CH and DOX 30CH), both in the absence or presence of chemical stress induced by doxorubicin at 0.3 µg/mL on follicular survival and activation, antioxidant capacity of the medium, Catalase activity (CAT), production of reactive protein thiol, maintenance of type I and III collagen fibers and accumulation of lipofuscin in porcine ovarian tissue cultured in vitro for 48 hours. To do this, part of the ovarian tissue fragments was fixed for the uncultured control and the rest were cultured in: MEM (cultured control), DOX 0.3 µg/mL, Ethanol, DOX 6CH, DOX 12CH, DOX 30CH, DOX (0.3 µg/mL) + DOX 6CH, DOX (0.3 µg/mL) + DOX 12CH, DOX (0.3 µg/mL) + DOX 30CH treatments. The results showed that, in general, ultradiluted/dynamized doxorubicin (DOX 6CH, DOX 12CH and DOX 30CH) mitigated the toxic effect of allopathic doxorubicin (0.3 µg/mL) on the morphology of preantral follicles, the content of type I and III collagen fibers, and the production of lipofuscin in the tissue. However, only DOX (0.3 µg/mL) + DOX 6CH attenuated the oxidative stress induced by DOX (0.3 µg/mL), maintaining adequate CAT activity that was similar to the uncultured control. Additionally, when the three isolated ultradiluted/dynamized doxorubicin were considered, only DOX 12CH increased the reduced thiol levels compared to the uncultured control and MEM. In conclusion, supplementing the culture medium with ultradiluted/dynamized DOX (DOX 6CH, DOX 12CH and DOX 30CH) attenuated the toxicity induced by allopathic doxorubicin during the in vitro culture of pig preantral follicles enclosed in ovarian tissue. • DOX ultradiluted/dynamized attenuated the toxicity induced by allopathic doxorubicin. • After 48 h, DOX ultradiluted/dynamized improved the survival of porcine preantral follicles. • The accumulation of lipofuscin was significantly reduced. • Proportions of type I and III collagen fibers and Catalase activity were maintained adequate. [ABSTRACT FROM AUTHOR]

This study sought to examine the ovarian cellular and stromal components of the zebrafish (Danio rerio) throughout the spawning season using light and electron microscopic tools. The ovaries of zebrafish showed oocytes in all stages of follicular development and degeneration (atresia). Six stages of oogenesis were demonstrated: oogonia, early oocytes, late oocytes, vacuolated follicles, the yolk globule stage (vitellogenesis), and mature follicles. The SOX9 protein was expressed in the ooplasm of the primary and previtellogenic oocytes and the theca cell layer of the mature follicles. Myostatin was expressed in the granulosa and theca cells. Many stem cells in the ovarian stroma expressed myostatin and SOX9. During the spawning season, the EM results indicated that the zona radiata increased in thickness and was crossed perpendicularly by pore canals that contained processes from both oocytes and zona granulosa. The granulosa cells contained many mitochondria, rER, sER, and vesicles. Meanwhile, the thecal layer consisted of fibroblast-like cells. Atretic follicles could be demonstrated that involved both oocytes and their follicular walls. Several types of cells were distinguished in the ovarian stroma, including mast cells, telocytes, lymphocytes, fibroblasts, endocrine cells, macrophages, adipocytes, dendritic cells, and steroidogenic (stromal) cells. The ovary of the zebrafish serves as a model to investigate follicular development.

Simple Summary: Control of reproduction in both males and females is complex, and a number of hormonal systems translate internal and/or external information to the hypothalamic-pituitary-gonadal (HPG) system. The control of reproduction integrates this high-energy demanding event to the internal (stored energy availability) and external (resources availability for progeny) conditions, thus increasing environmental fitting and offspring survival. In this paper, we describe new effects of the melanocortin system on gonadal physiology. Both adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormones (MSHs) modulate gonadal steroid secretion working throughout specific melanocortin receptors expressed in different gonadal cell types. The inhibitory effects of ACTH on gonadotropin-stimulated estradiol secretion seems to be related to the deleterious effects of stress on the female reproductive axis. On the contrary, the physiological involvement of MSH peptides on ovarian gametogenesis as well as the stimulatory effects of ACTH on testicular testosterone production remain unknown and further studies are required to understand melanocortin role on gonadal physiology. In teleost, as in other vertebrates, stress affects reproduction. A key component of the stress response is the pituitary secretion of the adrenocorticotropic hormone (ACTH), which binds to the melanocortin 2 receptor (MC2R) in the adrenal glands and activates cortisol biosynthesis. In zebrafish, Mc2r was identified in male and female gonads, while ACTH has been shown to have a physiological role in modulating reproductive activity. In this study, the hypothesis that other melanocortins may also affect how the zebrafish gonadal function is explored, specifically steroid biosynthesis, given the presence of members of the melanocortin signaling system in zebrafish gonads. Using cell culture, expression analysis, and cellular localization of gene expression, our new observations demonstrated that melanocortin receptors, accessory proteins, antagonists, and agonists are expressed in both the ovary and testis of zebrafish (n = 4 each sex). Moreover, melanocortin peptides modulate both basal and gonadotropin-stimulated steroid release from zebrafish gonads (n = 15 for males and n = 50 for females). In situ hybridization in ovaries (n = 3) of zebrafish showed mc1r and mc4r in follicular cells and adjacent to cortical alveoli in the ooplasm of previtellogenic and vitellogenic oocytes. In zebrafish testes (n = 3), mc4r and mc1r were detected exclusively in germ cells, specifically in spermatogonia and spermatocytes. Our results suggest that melanocortins are, directly or indirectly, involved in the endocrine control of vitellogenesis in females, through modulation of estradiol synthesis via autocrine or paracrine actions in zebrafish ovaries. Adult zebrafish testes were sensitive to low doses of ACTH, eliciting testosterone production, which indicates a potential role of this peptide as a paracrine regulator of testicular function. [ABSTRACT FROM AUTHOR]

Kisspeptins (KPs) secreted from the hypothalamic KP neurons act on KP receptors (KPRs) in gonadotropin (GPN) releasing hormone (GnRH) neurons to produce GnRH. GnRH acts on pituitary gonadotrophs to induce secretion of GPNs, namely follicle stimulating hormone (FSH) and luteinizing hormone (LH), which are essential for ovarian follicle development, oocyte maturation and ovulation. Thus, hypothalamic KPs regulate oocyte maturation indirectly through GPNs. KPs and KPRs are also expressed in the ovarian follicles across species. Recent studies demonstrated that intraovarian KPs also act directly on the KPRs expressed in oocytes to promote oocyte maturation and ovulation. In this review article, we have summarized published reports on the role of hypothalamic and ovarian KP-signaling in oocyte maturation. Gonadal steroid hormones regulate KP secretion from hypothalamic KP neurons, which in turn induces GPN secretion from the hypothalamic-pituitary (HP) axis. On the other hand, GPNs secreted from the HP axis act on the granulosa cells (GCs) and upregulate the expression of ovarian KPs. While KPs are expressed predominantly in the GCs, the KPRs are in the oocytes. Expression of KPs in the ovaries increases with the progression of the estrous cycle and peaks during the preovulatory GPN surge. Intrafollicular KP levels in the ovaries rise with the advancement of developmental stages. Moreover, loss of KPRs in oocytes in mice leads to failure of oocyte maturation and ovulation similar to that of premature ovarian insufficiency (POI). These findings suggest that GC-derived KPs may act on the KPRs in oocytes during their preovulatory maturation. In addition to the intraovarian role of KP-signaling in oocyte maturation, in vivo, a direct role of KP has been identified during in vitro maturation of sheep, porcine, and rat oocytes. KP-stimulation of rat oocytes, in vitro, resulted in Ca2+ release and activation of the mitogen-activated protein kinase, extracellular signal-regulated kinase 1 and 2. In vitro treatment of rat or porcine oocytes with KPs upregulated messenger RNA levels of the factors that favor oocyte maturation. In clinical trials, human KP-54 has also been administered successfully to patients undergoing assisted reproductive technologies (ARTs) for increasing oocyte maturation. Exogenous KPs can induce GPN secretion from hypothalamus; however, the possibility of direct KP action on the oocytes cannot be excluded. Understanding the direct in vivo and in vitro roles of KP-signaling in oocyte maturation will help in developing novel KP-based ARTs. [ABSTRACT FROM AUTHOR]

Three-dimensional cultures of follicles on ECM-based scaffolds can be an approach for women who become infertile after cancer treatments. Human amniotic membrane (HAM) is extensively employed in tissue engineering because of its unique properties. We cultured mouse pre-antral follicles in a hydrogel derived from decellularized amniotic membrane (DAM) combined with alginate (ALG) to improve ovarian follicle culture. HAM was decellularized. Quantitative (nuclear contents, collagen, glycosaminoglycan [GAG]) and qualitative (DAPI, H&E, Masson's trichrome, Alcian blue, scanning electron microscopy assessments were performed. Then, we created an amniotic membrane-based hydrogel (AMBH) and conducted AMBH characterization assays (rheology, MTS, degradation rate). Isolated mouse pre-antral follicles were cultured in 15 mg/mL AMBH (AMBH15), 30 mg/mL AMBH (AMBH30), or 45 mg/mL AMBH (AMBH45). ALG hydrogel was the control group. Follicular diameters, estradiol hormone secretion rate, follicular morphology, and the follicle antral and degeneration rate were examined. Quantitative and qualitative assays indicated successful decellularization. AMBH characterization assays showed that the ALG hydrogel had more appropriate gelation and slower degradation than AMBH. There was a statistically higher antral follicle formation rate in the AMBH45 group (p <.05) compared to the AMBH30 and AMBH15 groups and less (p <.05) degenerated follicles. There was no significant difference with the ALG group. Diameter and estradiol hormone secretion in the AMBH45 group were not significantly higher than the ALG group. Although decellularization was confirmed and the viscoelastic parameters of AMBH support follicle culture, there was no significant effect on ovarian follicle maturation compared to the ALG control group. [ABSTRACT FROM AUTHOR]

Introduction: Maternal nutrition intake affects the growth and development of foetal health. Poor nutritional intake contributes to adverse metabolic outcomes in the offspring at an advanced age, including its reproductive function. Maternal low-protein diet has been indicated to impair mitochondrial genetic expression in the offspring. This study aims to evaluate the impact of maternal low-protein diet on the folliculogenesis and mitochondrial distribution within ovarian follicles in female adult offspring of mice. Methods: Swiss Webster mice were nourished either normal protein diet containing 20% casein or low-protein diet (10% casein) during pregnancy and breastfeeding periods. Female offspring were weaned onto the control diet until 8 weeks of age. Female adult offspring were injected with 20 IU of FSH intraperitoneally to induce folliculogenesis. Folliculogenesis was assessed by morphological observation under a light microscope using haematoxylin-eosin staining, while mitochondrial distribution within ovarian follicles was identified by immunohistochemical staining of mitochondrial marker (ATP5A1). Immunostaining data were presented as fraction area (%) and quantified using ImageJ software. Results: The results from the low-protein diet group revealed a non-significant lower number of follicles at various stages compared to the normal protein diet group (p>0.05). The immunopositive expression of the mitochondrial marker in the low-protein diet group was notably lower than the control group (25.66% ± 4.90 vs 51.05% ± 1.51; p<0.05). Conclusion: Our study indicates that maternal low-protein diet during pregnancy and breastfeeding impairs folliculogenesis and mitochondrial distribution within the ovarian follicles in mice offspring later in life. [ABSTRACT FROM AUTHOR]

Simple Summary: Follistatin involves in the regulation of ovarian follicular development in mammals; however, the role of follistatin in goose ovarian follicular development has not been investigated. In this study, following immuno-neutralization of follistatin bioactivity in geese, the number of ovarian pre-ovulatory follicles significantly increased, and mRNA levels of genes involved in ovarian steroidogenesis and yolk deposition were upregulated in the granulosa layer of pre-hierarchical follicles. These results suggest that follistatin plays a limiting role in the development of ovarian pre-hierarchical follicles into pre-ovulatory follicles. These results also expand our understanding of the mechanism of follistatin on ovarian follicular development in geese. In order to explore the role of follistatin (FST) in ovarian follicular development and egg production in Yangzhou geese, sixty-four egg laying geese of the same genetic origin were selected and divided into two groups with equal numbers. One group was immunized against the recombinant goose FST protein by intramuscular injection, whereas the control group received bovine serum albumin (BSA) injection. Immunization against FST significantly increased the number of pre-ovulatory follicles. Furthermore, immunization against FST upregulated Lhr, Star, Vldlr, Smad3, and Smad4 mRNA levels in the granulosa layer of pre-hierarchical follicles. The results suggest that FST plays a limiting role in the development of ovarian pre-hierarchical follicles into pre-ovulatory follicles by decreasing follicular sensitivity to activin in geese. The mechanism may be achieved by regulating the SMAD3 signaling pathway, which affects progesterone synthesis and yolk deposition in pre-hierarchical follicles. [ABSTRACT FROM AUTHOR]

Developmental exposure to environmental chemicals (ECs) perturbs establishment and maintenance of the ovarian reserve across the reproductive lifetime, leading to premature follicle depletion and ovarian aging. Considering humans are exposed to a complex mixture of ECs, real-life models assessing their cumulative impact on the ovarian reserve are needed. Biosolids is a source of real-life mixture of ECs. While earlier studies demonstrated that grazing pregnant sheep on biosolids-treated pastures (BTP) did not influence establishment of the ovarian reserve in fetal life, its impact on subsequent depletion of ovarian reserve during reproductive life of offspring is unknown. We hypothesized that developmental exposure to biosolids accelerates depletion of ovarian reserve. Ovaries were collected from F1 juveniles (9.5 weeks) and adults (2.5 years) born to F0 ewes grazed on control inorganic fertilizer pastures or BTP from before conception and throughout gestation. The impact on follicular density, activation rate, and Anti-Müllerian hormone (AMH; mediator of activation) expression by immunohistochemistry was determined. Activation rate was increased in F1 BTP juveniles with a corresponding reduction in primordial follicle density. In contrast, activation rate and ovarian reserve were similar between control and F1 BTP adults. The density of AMH-positive antral follicles was lower in BTP juveniles, whereas AMH expression tended to be higher in antral follicles of BTP adults, consistent with the changes in the ovarian reserve. These findings of detrimental effects of developmental exposure to biosolids during juvenile life that normalizes in adults is supportive of a shift in activation rate likely related to peripubertal hormonal changes., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

3D culture of ovarian follicles in hydrogel matrices is an important emerging tool for basic scientific studies as well as clinical applications such as fertility preservation. For optimizing and scaling 3D culture of preantral follicles, there is a need for identifying biomaterial matrices that simplifies and improves the current culture procedures. At present, microencapsulation of follicles in alginate beads is the most commonly used approach. However, this technique involves notable manual handling and is best suited for encapsulation of single or several follicles. As a potential alternative, we here explore the suitability of different particle-based hydrogel matrices, where follicles can easily be introduced in tunable 3D environments, in large numbers. Specifically, we study the growth of secondary murine follicles in microgranular alginate and nanofibrillar cellulose matrices, with and without cell-binding cues, and map follicle growth against the viscoelastic properties of the matrices. We cultured follicles within the particle-based hydrogels for 10 days and continuously monitored their size, survival, and tendency to extrude oocytes. Interestingly, we observed that the diameter of the growing follicles increased significantly in the particle-based matrices, as compared to state-of-the-art alginate micro-encapsulation. On the other hand, the follicles displayed an increased tendency for early oocyte extrusion in the granular matrices, leading to a notable reduction in the number of intact follicles. We propose that this may be caused by impaired diffusion of nutrients and oxygen through thicker matrices, attributable to our experimental setup. Still, our findings suggest that viscoelastic, granular hydrogels represent promising matrices for 3D culture of early-stage ovarian follicles. In particular, these materials may easily be implemented in advanced culturing devices such as micro-perfusion systems., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Johan Ulrik Lind reports financial support was provided by the Technical University of Denmark. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Kisspeptins (KPs) secreted from the hypothalamic KP neurons act on KP receptors (KPRs) in gonadotropin (GPN) releasing hormone (GnRH) neurons to produce GnRH. GnRH acts on pituitary gonadotrophs to induce secretion of GPNs, namely follicle stimulating hormone (FSH) and luteinizing hormone (LH), which are essential for ovarian follicle development, oocyte maturation and ovulation. Thus, hypothalamic KPs regulate oocyte maturation indirectly through GPNs. KPs and KPRs are also expressed in the ovarian follicles across species. Recent studies demonstrated that intraovarian KPs also act directly on the KPRs expressed in oocytes to promote oocyte maturation and ovulation. In this review article, we have summarized published reports on the role of hypothalamic and ovarian KP-signaling in oocyte maturation. Gonadal steroid hormones regulate KP secretion from hypothalamic KP neurons, which in turn induces GPN secretion from the hypothalamic-pituitary (HP) axis. On the other hand, GPNs secreted from the HP axis act on the granulosa cells (GCs) and upregulate the expression of ovarian KPs. While KPs are expressed predominantly in the GCs, the KPRs are in the oocytes. Expression of KPs in the ovaries increases with the progression of the estrous cycle and peaks during the preovulatory GPN surge. Intrafollicular KP levels in the ovaries rise with the advancement of developmental stages. Moreover, loss of KPRs in oocytes in mice leads to failure of oocyte maturation and ovulation similar to that of premature ovarian insufficiency (POI). These findings suggest that GC-derived KPs may act on the KPRs in oocytes during their preovulatory maturation. In addition to the intraovarian role of KP-signaling in oocyte maturation, in vivo, a direct role of KP has been identified during in vitro maturation of sheep, porcine, and rat oocytes. KP-stimulation of rat oocytes, in vitro, resulted in Ca2+ release and activation of the mitogen-activated protein kinase, extracellular signal-regulated kinase 1 and 2. In vitro treatment of rat or porcine oocytes with KPs upregulated messenger RNA levels of the factors that favor oocyte maturation. In clinical trials, human KP-54 has also been administered successfully to patients undergoing assisted reproductive technologies (ARTs) for increasing oocyte maturation. Exogenous KPs can induce GPN secretion from hypothalamus; however, the possibility of direct KP action on the oocytes cannot be excluded. Understanding the direct in vivo and in vitro roles of KP-signaling in oocyte maturation will help in developing novel KP-based ARTs. [ABSTRACT FROM AUTHOR]

Iodoacetic acid (IAA) is an unregulated water disinfection byproduct that is an ovarian toxicant. However, the mechanisms of action underlying IAA toxicity in ovarian follicles remain unclear. Thus, we determined whether IAA alters gene expression in ovarian follicles in mice. Adult female mice were dosed with water or IAA (10 or 500 mg/L) in the water for 35-40 days. Antral follicles were collected for RNA-sequencing analysis and sera were collected to measure estradiol. RNA-sequencing analysis identified 1063 differentially expressed genes (DEGs) in the 10 and 500 mg/L IAA groups (false discovery rate FDR < 0.1), respectively, compared to controls. Gene Ontology Enrichment analysis showed that DEGs were involved with RNA processing and regulation of angiogenesis (10 mg/L) and the cell cycle and cell division (500 mg/L). Pathway Enrichment analysis showed that DEGs were involved in the phosphatidylinositol 3-kinase and protein kinase B (PI3K-Akt), gonadotropin-releasing hormone (GnRH), estrogen, and insulin signaling pathways (10 mg/L). Pathway Enrichment analysis showed that DEGs were involved in the oocyte meiosis, GnRH, and oxytocin signaling pathways (500 mg/L). RNA-sequencing analysis identified 809 DEGs when comparing the 500 and 10 mg/L IAA groups (FDR < 0.1). DEGs were related to ribosome, translation, mRNA processing, oxidative phosphorylation, chromosome, cell cycle, cell division, protein folding, and the oxytocin signaling pathway. Moreover, IAA exposure significantly decreased estradiol levels (500 mg/L) compared to control. This study identified key candidate genes and pathways involved in IAA toxicity and can help to further understand the molecular mechanisms of IAA toxicity in ovarian follicles. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate ovarian follicular activity, ovulation percentage, and body weight change in response to focused nutrition during synchronization of oestrus with an intravaginal device (CIDR®) (9 days) in Pelibuey ewes with high and low body condition. Seventy-two non-pregnant ewes without offspring were randomly distributed to one of four treatments, namely T1: (n = 18) ewes without focused nutrition and low body condition; T2: (n = 18) ewes without focused nutrition and high body condition; T3: (n = 18) ewes with focused nutrition and low body condition; and T4: (n = 18) ewes with focused nutrition and high body condition. While the CIDR device was in place, the ewes with focused nutrition received a supplement of 1.5 kg ewe/day, which contained 2.9 MCal metabolizable energy, 16% crude protein, 88.5% dry matter, 11.8% crude fibre, and 6.7% of ash. The concentration of progesterone (P4) was measured to determine ovulation percentage. The follicular population was quantified (2-3 mm, 4-5 mm, and >6 mm in diameter). The number of follicles between 2-3 mm and 4-5 mm in diameter was similar among treatments. The number of follicles >6 mm in diameter was higher in T4 ewes (2.2 ± 0.2) compared with T1, T2, and T3. The response to oestrus, the onset of oestrus, and the ovulation percentage were similar among treatments. Focused nutrition increased the number of ovarian follicles >6 mm in diameter in ewes with high body condition. [ABSTRACT FROM AUTHOR]

Objective: To identify relationships between the size of punctured ovarian follicles and subsequent embryology outcomes.Design: Prospective observational cohort study.Setting: Private fertility center.Patients: One hundred fifty-seven oocyte retrievals performed during the study period.Interventions: The diameter of punctured follicles was ultrasonically measured during routine oocyte collection. The resulting embryos were group-cultured to the blastocyst stage and classified into 8 groups according to follicle size (≤9.5, 10-12.5, 13-15.5, 16-18.5, 19-21.5, 22-24.5, 25-27.5, and ≥28 mm).Main Outcome Measure: Rate of good-quality blastocysts per follicle puncture.Results: This study included 4,539 follicle punctures, 2,348 oocytes, 1,772 mature oocytes, 1,258 bipronuclear (2pn) oocytes, and 571 good-quality blastocysts derived from 157 oocyte retrievals. The per-puncture yields of oocytes, mature oocytes, 2pn oocytes, and good-quality blastocysts were associated with the size of the punctured follicle. The rates of good-quality blastocysts per punctured follicle were 2.2% (≤9.5 mm), 6.2% (10-12.5 mm), 11.9% (13-15.5 mm), 14.5% (16-18.5 mm), 18.9% (19-21.5 mm), 17.5% (22-24.5 mm), 15.9% (25-27.5 mm), and 16.0% (≥28 mm). When compared with the overall average, punctures of follicles in groups ≤12.5 mm in diameter had significantly inferior yields of good-quality blastocysts, whereas punctures of follicles in groups 19-24.5 mm in diameter were associated with significantly greater than average yields of good-quality blastocysts. Other groups did not differ significantly from average. No correlation was observed between follicle diameter and ploidy of biopsied blastocysts.Conclusions: Punctures of follicles ≤12.5 mm in diameter rarely result in good-quality blastocysts. The yield of good-quality blastocysts progressively increases with follicle size up to approximately 19 mm in diameter, with no substantial decline above that size. The ploidy of the blastocysts that form appears to be unaffected by follicle size. [ABSTRACT FROM AUTHOR]

Early prediction of the reproductive success of sturgeon females is important both for artificial breeding conditions in sturgeon farms and for monitoring wild fish populations approaching spawning. This study demonstrated that ovarian follicles removed from wintering Acipenser baerii females can undergo in vitro ovulation when exposed to 17α,20β-dihydroxy-4-pregnen-3-one. The research was conducted from 2015 to 2021 and involved the examination of 110 wintering Siberian sturgeon females (A. baerii), with an average weight of 8–11 kg and an age range of 8–10 years. Selection of females for spawning was based on the polarization index (PI) at the time when the river temperature dropped to +8 °C. The selected females were overwintered in concrete flow-through tanks with water from the Volga River for approximately two months. At the end of this period, oocyte samples were collected for in vitro incubation. An increase in water temperature to 15 °C, which precedes spawning, was achieved by mixing with warm effluent from a regional power station. The reproductive success of females was evaluated based on fertilization and embryonic survival rates. High reproductive success was characterized by females with fertilization rates above 70% and hatching rates above 60%. We identified a positive correlation between the percentage of in vitro ovulated follicles and the in vivo fertilization and embryo survival rates, with correlation coefficients of Rsp = 0.60 and Rsp = 0.48, respectively. Statistical analysis showed that females whose in vitro ovulation rate of follicles exceeded 30% displayed high reproductive performance compared to those with an in vitro ovulation rate below 30%. The predictive accuracy of this criterion was determined by calculating the ratio of ranks between females with high and low reproductive performance, averaging 80.9% for fertilization and 77% for embryonic survival. Therefore, we propose a new criterion to select females of A. baerii for spawning based on the in vitro oocyte ovulation rate obtained from wintering individuals. • A criterion to predict the reproductive success of sturgeon females was developed • Ovarian follicles from 110 Siberian sturgeon females were incubated in vitro • In vitro ovulation rate correlated with in vivo egg fertilization and hatching rates • The criterion allows choosing the best sturgeon females among wintering fishes • The correct predictions average 81% and 70% for fertilization and hatching [ABSTRACT FROM AUTHOR]