Follicle-stimulating Hormone Release Research Articles

Revolutionizing Infertility Management through Novel Peptide-based Targets.

Around 48 million couples and 186 million people worldwide have infertility; of these, approximately 85% have an identifiable cause, the most common being ovulatory dysfunctions, male infertility, polycystic ovary syndrome, and tubule disease. The remaining 15% have infertility for unknown reasons, including lifestyle and environmental factors. The regulation of the hypothalamic- pituitary-adrenal axis (HPA) is crucial for the secretion of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH), which are essential for female reproductive functions. GnRH is the primary reproductive axis regulator. The pattern of GnRH, FSH, and LH release is determined by its pulsatile secretion, which in turn controls endocrine function and gamete maturation in the gonads. Peptides called Kisspeptin (KP), Neurokinin-B (NKB), and Orexin influence both positive and negative feedback modulation of GnRH, FSH, and LH secretion in reproduction. This review article mainly focuses on the historical perspective, isoform, and signaling pathways of KP, NKB, and Orexin novel peptide-based targets including clinical and preclinical studies and having a promising effect in the management of infertility.

Central MOTS-c infusion affects reproductive hormones in obese and non-obese rats

MOTS-c, a mitochondrial-derived peptide, acts as a systemic hormone and MOTS-c level is inversely correlated with markers of obesity. Obesity is a risk factor for male reproductive physiology and is expressed as an important cause of infertility. In this study, we aimed to determine the effects of MOTS-c, which has been proven in the hypothalamus and testicles, on the actors involved in the reproductive axis.In the study, 80 male Wistar-Albino rats were divided into two main groups, obese and non-obese (n = 40). Rats in the first main group were fed with fatty diet feed and obesity was induced. The second main group was fed with normal diet feed. Each main group was divided into 4 subgroups (Control, Sham, 10 and 100 µM MOTS-c). The lateral ventricles of the animals in the treatment groups were infused with 10 and 100 µM MOTS-c (solvent in Sham group) for 14 days. At the end of the experiment, hypothalamic Gonadotropin-Releasing Hormone (GnRH) gene expression level, serum testosterone, Luteinizing hormone (LH) and Follicle stimulating hormone (FSH) levels were determined.MOTS-c infusion caused an increase in GnRH mRNA, protein expression levels and serum testosterone, LH and FSH levels in obese and non-obese rats (p < 0.05). MOTS-c administration more significantly upregulated hormone levels in non-obese rats (p < 0.05). MOTS-c administration increases these hormones, suggesting that MOTS-c may stimulate the reproductive axis.Our results reveal that MOTS-c plays a role in the central regulation of reproduction, as well as causes increased LH, FSH and testosterone release.

Morphological assessment of ovaries during stimulation of ovulation in rab-bits with equine serum gonadotropin in different doses

Ovulatory stimulation of rabbits during artificial insemination requires the use of hormonal drugs to stimulate maturation of follicles, effective fertilization and full manifestation of female sexual function. For this purpose, gonadotropins or analogues of gonadotropin-releasing hormone are common in the practice of rabbit breeding. The latter have a selective effect on folliculogenesis and, under certain conditions, are not capable of inducing ovulation in rabbits of “zero” reproductive cycle, that is, those that have not given birth. Instead, gonadotropins, in particular serum gonadotropin obtained from foal mares (eCG), have a pronounced effect on folliculogenesis in animals. eCG is a glycoprotein hormone secreted by trophoblastic epithelial cells of fetal origin. In other species, except for horses, it is able to induce the release of both luteinizing and follicle-stimulating hormone. That is why eCG is widely used together with human chorionic gonadotropin to induce follicle growth and ovulation. However, there are data on complications and pathological conditions that may occur with long-term use of eCG, especially in genital tract. Therefore, the goal of our research was the morphological evaluation of the functional compartments of ovaries when using eCG to stimulate reproductive function of rabbits. Schemes of hormonal treatment of females in the conditions of a private rabbit farm, an experiment was conducted, which included the introduction of eCG in different doses (40 IU for animals of experimental group 1 and 25 IU for experimental group 2) during five reproductive cycles. Selection of material for histological studies, its fixation, production and analysis of tissue sections stained with hematoxylin and eosin were performed according to commonly used methods. The complex of morphofunctional changes in the ovaries of the rabbits of experimental groups corresponds to the pathomorphological picture of the syndrome of hyperstimulated ovaries. In our experiment, obtained changes were more pronounced at a dose of 40 IU, using which we additionally detected signs of increased immunoreactivity in body of rabbits, as evidenced by the presence of nodular lymphoid formations in outer theca of secondary and tertiary follicles. Thus, as a safe regimen for the use of eCG for ovulatory stimulation in rabbits, we recommend a dosage of 25 IU for 1–2 reproductive cycles.

Engineered Nano-carrier systems for the oral targeted delivery of follicle stimulating Hormone: Development, characterization, and, assessment of in vitro and in vivo performance and targetability

Follicle stimulating hormone (FSH) is widely used for the treatment of female infertility, where the level of FSH is suboptimal due to which arrest in follicular development and anovulation takes place. Currently, only parenteral formulations are available for FSH in the market. Due to the drawbacks of parenteral administration and the high market shares of FSH, there is a need for easily accessible oral formulation. Therefore, enteric coated capsules filled with FSH loaded nanostructured lipid carriers (NLCs) or liposomes were prepared. Preliminary studies such as circular dichroism, SDS-PAGE, FTIR and ELISA were conducted to analyze FSH. Prepared formulations were optimized with respect to the size, polydispersity index, zeta potential, and entrapment efficiency using the design of experiments. Optimized formulations were subjected to particle counts and distribution analysis, TEM analysis, in vitro drug release, dissolution of enteric coated capsules, cell line studies, everted sac rat's intestinal uptake study, pharmacokinetics, pharmacodynamics, and stability studies. In the case of liposomes, RGD conjugation was done by carbodiimide chemistry and conjugation was confirmed by FTIR, 1HNMR and Raman spectroscopy. The prepared formulations were discrete and spherical. The release of FSH from enteric coated capsules was slow and sustained. The increased permeability of nano-formulations was observed in Caco-2 monoculture as well as in Caco-2 and Raji-B co-culture models. NLCs and liposomes showed an improvement in oral bioavailability and efficacy of FSH in rats. This may be due to mainly chylomicron-assisted lymphatic uptake of NLCs; whereas, in the case of liposomes, RGD-based targeting of β1 integrins of M cells on Peyer's patches may be the main reason for the better effect by FSH. FSH was found to be stable chemically and conformationally. Overall, the study reveals the successful development and evaluation of FSH loaded NLCs and liposomes.

Follistatin is a crucial chemoattractant for mouse decidualized endometrial stromal cell migration by JNK signalling

Follistatin (FST) and activin A as gonadal proteins exhibit opposite effects on follicle-stimulating hormone (FSH) release from pituitary gland, and activin A-FST system is involved in regulation of decidualization in reproductive biology. However, the roles of FST and activin A in migration of decidualized endometrial stromal cells are not well characterized. In this study, transwell chambers and microfluidic devices were used to assess the effects of FST and activin A on migration of decidualized mouse endometrial stromal cells (d-MESCs). We found that compared with activin A, FST exerted more significant effects on adhesion, wound healing and migration of d-MESCs. Similar results were also seen in the primary cultured decidual stromal cells (DSCs) from uterus of pregnant mouse. Simultaneously, the results revealed that FST increased calcium influx and upregulated the expression levels of the migration-related proteins MMP9 and Ezrin in d-MESCs. In addition, FST increased the level of phosphorylation of JNK in d-MESCs, and JNK inhibitor AS601245 significantly attenuated FST action on inducing migration of d-MESCs. These data suggest that FST, not activin A in activin A-FST system, is a crucial chemoattractant for migration of d-MESCs by JNK signalling to facilitate the successful uterine decidualization and tissue remodelling during pregnancy.

Kallmann syndrome

Kallmann syndrome (KS) is a form of hypogonadotropic hypogonadism characterized by a combination of both an inability to smell and properly regulate hypothalamic gonadotropin-releasing hormone (GnRH) pulses. This, as a result, affects the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary gland, which in turn influences the secretion of endocrine hormones, such as estrogen and progesterone. It is found fairly infrequently, at a rate of approximately 1 in every 125,000 females and 1 in every 30 000 males. The inability to regulate GnRH secretion from the hypothalamus leads to a variety of consequences, including reduced sex hormone levels and the delayed onset of puberty.

Development of relugolix combination therapy as a medical treatment option for women with uterine fibroids or endometriosis

Treatment of uterine fibroids (UF) and endometriosis (EM) has relied on the surgical skills of gynecologists to improve symptoms and potentially alter the course of these debilitating diseases. Medical management of symptoms for both diseases leverages combined hormonal contraceptives used off label as a first-line treatment, with nonsteroid anti-inflammatory drugs and opioids to manage pain as needed. Gonadotropin-releasing hormone (GnRH) receptor agonists (peptide analogs) have been used as short-term therapy to manage severe symptoms of UF or EM, treat anemia, and reduce fibroid size before surgery. The introduction of oral GnRH receptor antagonists opened the door for the development of new treatment options for UF, EM, and other estrogen-driven diseases. Relugolix is an orally active, nonpeptide, GnRH receptor antagonist that competitively binds to GnRH receptors, preventing the release of follicle-stimulating hormone and luteinizing hormone (LH) into the systemic circulation. In women, the reduction in follicle-stimulating hormone concentrations prevents natural follicular development, suppressing ovarian production of estrogen, and together with reductions in LH concentrations, prevent ovulation, corpus luteum formation, and, thereby, the production of progesterone (P). By reducing circulating concentrations of estradiol (E2) and P, relugolix improves heavy menstrual bleeding and other symptoms associated with UF and moderate to severe pain associated with EM, including dysmenorrhea, nonmenstrual pelvic pain (NMPP) and dyspareunia. However, as monotherapy, the use of relugolix is associated with signs and symptoms of a hypoestrogenic state, including bone mineral density loss and vasomotor symptoms. The clinical development of relugolix incorporated the addition of a 1 mg dose of E2 and a 0.5-mg dose of norethindrone acetate (NETA) to achieve systemic E2 concentrations that remain in a therapeutic range while mitigating the risk for bone mineral density loss and vasomotor symptoms, enabling the longer-term treatment and reducing the impact of symptoms on quality of life, and potentially delaying or preventing the need for surgery. Relugolix 40 mg in combination with estradiol (E2) 1 mg and NETA 0.5 mg as a single fixed-dose combination tablet (relugolix combination therapy [relugolix-CT]) approved in the United States as MYFEMBREE is the first and only once daily oral GnRH antagonist combination therapy indicated for the management of heavy menstrual bleeding associated with UF and moderate to severe pain associated with EM. In the European Union (EU) and the United Kingdom (UK), relugolix-CT is approved as RYEQO for the management of symptoms associated with UF. In Japan, relugolix 40 mg, as monotherapy, was the first GnRH receptor antagonist approved to improve symptoms associated with UF or pain associated with EM under the brand name RELUMINA. In men, relugolix suppresses testosterone production. Relugolix 120 mg (ORGOVYX) was developed by Myovant Sciences and is approved in the United States, EU, and UK as the first and only oral androgen-deprivation therapy for the treatment of advanced prostate cancer. This review is focused on the development of relugolix and relugolix-CT in women's health indications.

Linzagolix: an oral gonadotropin-releasing hormone receptor antagonist treatment for uterine fibroid-associated heavy menstrual bleeding

Gonadotropin-releasing hormone receptor antagonists, as selective gonadotropin-releasing hormone receptor blockers, reduce the release of follicle-stimulating hormone and luteinising hormone from the pituitary, resulting in anovulation and amenorrhea in a dose-dependent manner.1 The suppression of gonadotropin-releasing hormone receptor presents several potential therapeutic options for hormone-dependent disorders, such as endometriosis, uterine fibroids, prostatic hyperplasia, or prostate cancer.

Maximizing Correction of Infertility with Moderate to Marked Diminished Egg Reserve in Natural Cycles by Up-Regulating Follicle Stimulating Hormone Receptors

Many infertility specialists advise women with diminished oocyte reserve (DOR) that their remaining oocytes probably are of poor quality similar to women of advanced reproductive age. There have been studies, especially employing in vitro fertilization-embryo transfer (IVF-ET), showing very poor live delivered pregnancy rates despite the transfer of morphologically normal embryos in women even with mild DOR. However, other data suggests that the low pregnancy rates are related to the use of high dosages of follicle stimulating hormone (FSH) drugs which down-regulate some key FSH dependent enzymes, cytokines, or proteins required for proper embryo implantation. Some studies have shown that techniques that favor FSH receptor up-regulation, rather than down-regulation, can provide the chance of live delivery 80% as well in women ≤ 35 with DOR, 70% for women 36-39, and 50% for women 40-42. Though some infertility specialists will encourage women whose only infertility issue is DOR, who reject the initial suggestion to consider donor oocytes, to proceed immediately with IVF-ET to maximize success, pregnancies are quite possible with natural conception. Thus, it seems imprudent to make couples undergo the financial burden of IVF-ET in the absence of a significant tubal or male factor problem. Not only have live deliveries occurred in women with DOR, using the principle described to achieve a mature dominant follicle followed by proper luteal phase support, with serum FSH levels over 100 mIU/mL, but also serum Anti-Mullerian Hormone (AMH) levels that were undetectable. This even applies to women in overt menopause where FSH up-regulation was achieved by negative feedback to the pituitary using ethinyl estradiol inhibiting FSH release, or down-regulation of hypothalamic-pituitary stimulation of FSH production by using gonadotropin releasing hormone agonists or antagonists.

Putative Role of the Kisspeptin/Kiss1R System in Promoting Hypothalamic GnRH Release, Pubertal Maturation, and Regulation of Ovulation Considering the Central Reproductive Axis

Kisspeptin is a class of neuropeptides that are the product of the Kiss1 gene. These neuropeptides play an important role in maintaining gonadotropin-releasing hormone (GnRH) levels and their release through hypothalamic neurons. Subsequently, they also play an important role in maintaining gonadotropin levels, as GnRH levels stimulate the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which allow induction of gametogenesis of pubertal maturation. The importance of the Kiss1 gene in reproduction became evident when natural mutations in this gene were discovered, which were associated with hypothalamic hypogonadism (HH) and delayed puberty. Kisspeptin and its KISS1R receptors are expressed in the mammalian ovary. The putative role of the Kisspeptin system in the ovary directly controls oocyte maturation, follicular development, and ovulation in an autocrine and paracrine fashion. These essential facts of kisspeptin and its receptor are necessary to maintain the central reproductive axis.

Characteristics of Neurokinin-3 Receptor and Its Binding Sites by Mutational Analysis.

Simple SummaryThis study presents in silico models of neurokinin B receptor tiTac3Ra (tilapia Tachykinin 3 receptor a) and its potential binding sites, as well as docking native tilapia Neurokinin F (tiNKF) and tilapia Neurokinin B (tiNKB) to theses orthosteric binding sites. For a better understanding of the binding confirmation and interaction of the structures, we compared the conformation between peptide docking and induced fit docking results. We have tried to analyze the affinity of binding and binding site interactions parallel to in-vitro results of receptor activity. NKB antagonists inhibit male tilapia gonadal development and gonadotropin release. We further verified the in-vivo effect of the antagonists on gonadal development in males. Studying the receptor activity of variants with alanine mutations at Phe2516.44 and Met2897.43 respectively, we found that, while both variants completely underperformed, there was no direct interaction with the ligand in the binding process indicating their role in post binding receptor activation rather than the binding process itself.NKB (Neurokinin B) is already known to play a crucial role in fish reproduction, but little is known about the structure and function of NKB receptors. Based on an in silico model of the tilapia NKB receptor Tachykinin 3 receptor a (tiTac3Ra) found in the current study, we determined the key residues involved in binding to tilapia NKB and its functional homologue NKF (Neurokinin F). Despite studies in humans suggesting the crucial role of F2516.44 and M2897.43 in NKB binding, no direct peptide interaction was observed in tilapia homologs. In-silico, Ala mutations on residues F2516.44 and M2897.43 did not influence binding affinity, but significantly affected the stability of tiTac3Ra. Moreover, in vitro studies indicated them to be critical to tiNKB/tiNKF-induced receptor activity. The binding of NKB antagonists to tiTac3Ra both in-vitro and in vivo inhibits FSH (follicle stimulating hormone) and LH (luteinizing hormone) release and sperm production in mature tilapia males. Non-peptide NKB antagonist SB-222200 had a strong inhibitory effect on the Tac3Ra activation. SB-222200 also decreased LH plasma levels; two hours post intraperitoneal injection, changed sperm volume and the ratios of the different stages along the spermatogenesis in tilapia testes.

Ovarian Function Suppression With Luteinizing Hormone-Releasing Hormone Agonists for the Treatment of Hormone Receptor-Positive Early Breast Cancer in Premenopausal Women.

Chemotherapy and endocrine therapies are mainstays of treatment for early and advanced hormone receptor-positive (HR+) breast cancer. In premenopausal women with HR+ tumors, the benefits of adding ovarian function suppression (OFS) to endocrine therapy have been debated. Consequently, for many years, tamoxifen monotherapy has been the standard of care for endocrine treatment in the adjuvant setting. Recent studies have, however, provided new evidence that, in some premenopausal patients, OFS in combination with tamoxifen or aromatase inhibitors (AIs) can significantly increase survival versus tamoxifen alone. Luteinizing hormone-releasing hormone agonists (LHRHa), including goserelin, triptorelin, and leuprorelin, achieve OFS through sustained suppression of the release of follicle-stimulating hormone and luteinizing hormone from the pituitary. In turn, this suppresses production and secretion of estradiol, an ovarian hormone that supports cancer cell growth, survival, and proliferation. In this review, we discuss the clinical evidence supporting the addition of LHRHa to adjuvant endocrine therapies, including tamoxifen and AIs, for premenopausal women with breast cancer. We also discuss the role of LHRHa use in combination with adjuvant chemotherapy to preserve ovarian function and fertility in young patients with breast cancer. Finally, we discuss important practical aspects of the use of LHRHa in breast cancer treatment, including side-effects, patient adherence to treatment, and the use of slow-release, long-acting drug formulations.

Hormonal and neuroendocrine control of reproductive function in teleost fish.

Reproduction is one of the important physiological events for the maintenance of the species. Hormonal and neuroendocrine regulation of teleost requires multiple and complex interactions along the hypothalamic-pituitary-gonad (HPG) axis. Within this axis, gonadotropin-releasing hormone (GnRH) regulates the synthesis and release of gonadotropins, follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Steroidogenesis drives reproduction function in which the development and differentiation of gonads. In recent years, new neuropeptides have become the focus of reproductive physiology research as they are involved in the different regulatory mechanisms of these species' growth, metabolism, and reproduction. However, especially in fish, the role of these neuropeptides in the control of reproductive function is not well studied. The study of hormonal and neuroendocrine events that regulate reproduction is crucial for the development and success of aquaculture.

PTPN5 promotes follicle‐stimulating hormone secretion through regulating intracellular calcium homeostasis

Protein tyrosine phosphatase non-receptor type 5 (PTPN5), also called striatal-enriched protein tyrosine phosphatase (STEP), is highly expressed in neurons of the basal ganglia, hippocampus, cortex, and related structures, also in the pituitary. Gonadotropins are the key regulator of the reproduction in mammals. In this study, PTPN5 is detected to express in murine pituitary in a developmental manner. Moreover, the expression of PTPN5 in the pituitary is heavily reduced after ovary removal. Follicle-stimulating hormone (FSH) secretion in gonadotropes is regulated by PTPN5 via binding GnRH to GnRH-R. Two parallel signaling pathways, Gs-protein kinase A (PKA)-PTPN5 and Gq-phospholipases C (PLC)-p38 MAPK-PTPN5, cooperatively regulate GnRH-induced FSH secretion. We also show that influx of Ca2+ activates the Ca2+ -dependent phosphatase calcineurin, leading to the phosphorylation and activation of PTPN5. The intracellular release of Ca2+ is reduced via TC2153. In conclusion, blocking or knocking out of PTPN5 reduces the release of FSH in whole pituitary. Mechanically, PTPN5 regulates gonadotropes' function through regulating intracellular calcium homeostasis.

Dioscorea deltoidea Leaf Extract (DDLE) Attenuates Cisplatin-Induced Ovarian Injury via Regulation of Oxidative Stress.

The present study investigated Dioscorea deltoidea leaf extract (DDLE) for treatment of cisplatin-induced ovarian injury in rat model. DDLE treatment of the cisplatin-induced ovarian injury rats suppressed Follicle-stimulating hormone (FSH) release and promoted the estrogen E2 level in serum samples. Development of follicles was increased while as damage to ovarian cortex on day 14, 28, and 42 was inhibited in cisplatin-induced ovarian injury rats on treatment with DDLE. In cisplatin-induced ovarian injury rat model oxidative stress showed a significant increase because of reduction in the level of antioxidant enzyme activity. However, DDLE treatment led to a prominent increase in activity of antioxidant enzyme compared to the control group. Moreover, DDLE treatment regulated the expression of Nuclear factor erythroid 2-related factor 2 protein in cisplatin-induced ovarian injury rats. In conclusion, DDLE treatment prevents cisplatin-induced ovarian injury through inhibition of malondialdehyde (MDA) level and upregulation of superoxide dismutase (SOD) and catalase (CAT) activity.

Effect of kisspeptin (KISS) and RFamide-related peptide-3 (RFRP-3) on the synthesis and secretion of FSH in vitro by pituitary cells in pigs

Kisspeptins (KISSs) and RFamide-related peptide-3 (RFRP-3) affect the synthesis and secretion of luteinizing hormone (LH) and modulate female reproductive processes. The presence of KISS and RFRP-3 in the porcine pituitary gland and their contribution to the regulation of follicle-stimulating hormone (FSH) synthesis and secretion is unknown. This study analyzed the presence of KISS and RFRP-3 in the pituitary of estrous-cyclic pigs on days 2 to 3, 10 to 11, 12 to 13, 15 to 16 and 19 to 20 and early pregnant pigs on days 10 to 11, 12 to 13 and 15 to 16, and evaluated the effect of KISS and RFRP-3 on β-Fsh mRNA expression and FSH secretion in vitro by pituitary cells collected on selected days of the estrous cycle. The cells were cultured in vitro and treated with KISS (10−6 M, 10−7 M) and RFRP-3 (10−6 M, 10−7 M) or gonadotropin-releasing hormone (GnRH; 100 ng/mL) alone and in combinations (4 h or 24 h). The relative abundance of Kiss and Rfrp-3 and their receptor mRNA transcripts, as well as the KISS and RFRP-3 proteins, were found in the pituitaries of estrous-cyclic and early pregnant pigs. KISS after 4 h increased the secretion of FSH in estrous cyclic pigs mostly during the early-luteal phase and luteolysis. RFRP-3 inhibited the synthesis and secretion of FSH in estrous-cyclic pigs on days 19 to 20 and the secretion of FSH on days 2 to 3 and 10 to 12 of the estrous cycle compared with GnRH-treated cells. KISS in co-treatment with GnRH after 24 h enhanced FSH release on days 2 to 3 and 15 to 16 of the estrous cycle. In conclusion, KISS and RFRP-3 systems are present in the pituitary of estrous-cyclic and pregnant pigs. In estrous-cyclic pigs, KISS and RFRP-3 may affect the synthesis and secretion of FSH by pituitary cells.

Distribution of GnRH and Kisspeptin Immunoreactivity in the Female Llama Hypothalamus.

Llamas are induced non-reflex ovulators, which ovulate in response to the hormonal stimulus of the male protein beta-nerve growth factor (β-NGF) that is present in the seminal plasma; this response is dependent on the preovulatory gonadotrophin-releasing hormone (GnRH) release from the hypothalamus. GnRH neurones are vital for reproduction, as these provide the input that controls the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the pituitary gland. However, in spontaneous ovulators, the activity of GnRH cells is regulated by kisspeptin neurones that relay the oestrogen signal arising from the periphery. Here, we investigated the organisation of GnRH and kisspeptin systems in the hypothalamus of receptive adult female llamas. We found that GnRH cells exhibiting different shapes were distributed throughout the ventral forebrain and some of these were located in proximity to blood vessels; sections of the mediobasal hypothalamus (MBH) displayed the highest number of cells. GnRH fibres were observed in both the organum vasculosum laminae terminalis (OVLT) and median eminence (ME). We also detected abundant kisspeptin fibres in the MBH and ME; kisspeptin cells were found in the arcuate nucleus (ARC), but not in rostral areas of the hypothalamus. Quantitative analysis of GnRH and kisspeptin fibres in the ME revealed a higher innervation density of kisspeptin than of GnRH fibres. The physiological significance of the anatomical findings reported here for the ovulatory mechanism in llamas is still to be determined.

Treatment of uterine bleeding in pubertal girls without application of hormonal therapy on the background of related thyroid pathology

Pubertal uterine bleeding occupies an important place in the structure of gynecological pathology since, in the years, it can lead to persistent and irreversible changes in the process of formation of the reproductive system.The purpose of the work is to investigate the effectiveness of non-hormonal therapy in the treatment of uterine bleeding in adolescent girls against the background of concomitant thyroid pathology.Material and methods. Thirty adolescent girls with pubertal uterine bleeding were examined and treated against the background of concomitant thyroid pathology, which were treated in the gynecological department of the city clinical maternity hospital No. 1 in Chernivtsi. All examined patients also underwent a comprehensive examination to determine the level of hormones in the blood serum and to determine individual indicators of hemostasis.Results. It was established that the complex therapy used in adolescent girls suffering from pubertal uterine bleeding against the background of thyroid pathology is effective, as indicated by the positive feedback mechanism, namely the release of follicle-stimulating hormone in response to an increase in the level of estradiol in peripheral blood.Conclusion. The comprehensive treatment technique developed and used by us in adolescent girls with uterine bleeding with concomitant thyroid pathology contributes to the gradual normalization of the level of sex and thyroid hormones in the blood serum, shortens the treatment period in the hospital, and helps to normalize the overall hormonal profile of the examined girls with concomitant thyroid pathology.

Osteoprotective effect of bread enriched with protein, dietary fiber, calcium, iron and iodine in hypoestrogen-induced osteoporosis among rats

The search for new strategies for the prevention and control of osteoporosis is an urgent task. Functional foodstuffs and their components are of particular interest in this regard. The aim was to study the effect of bread enriched with protein, dietary fiber, calcium, iron and iodine on the state of the bone tissue of rats in a model of postmenopausal osteoporosis. Material and methods. The experiment was performed on sexually mature female Wistar rats divided into groups: K - control (sham-operated rats, not ovariectomized); О30 - osteoporosis model (animals were sacrificed 30 days after ovariectomy); groups О120 and О120+ - a model of osteoporosis (rats were sacrificed 120 days after ovariectomy). All animals were fed a standard vivary diet. For rats of the О120+ group, from the 40th to the 120th day, enriched bread was included in the diet in an amount of 6 g per 100 g of body weight per day. The bread was fortified with protein (whey protein, blood plasma proteins from farm animals), dietary fiber, calcium (eggshell), iron (purified hemoglobin) and iodized whey protein. Animals of groups K and О120 received unfortified bread in the same amount. Blood levels of total calcium (by colorimetric method), gonadotropins, testosterone, and estradiol (by enzyme-linked immunosorbent assay) were analyzed. Microtomographic evaluation of the architecture and mineral density of the trabecular part of the femur and lumbar vertebrae was performed. Histomorphological analysis of the uterus and femur of animals was performed. Results and discussion. In animals of the О120+ group, in comparison with the О120 sample, there was a decrease in blood testosterone and a marked compensatory release of follicle-stimulating hormone, while no changes were detected in the concentration of estradiol and the state of the uterus atrophied against the background of ovariectomy. There was an increase in the trabecular mineral density of the femur and lumbar vertebrae. The proportion of bone trabeculae in the total volume of the femoral metaphysis (BV/TV) in animals of the О120+ sample was 12.5±0.66% compared to 10.4±0.52% in the О120 group. The values of the structural model index (SMI) reflecting the loss of bone strength and the trabecularity coefficient (TbPf) in О120+ rats (1.44±0.07 and 5.96±0.29 1/mm) were significantly lower than these parameters in the О120 group (1.74±0.08; 9.13±0.46 1/mm, р<0.05). The micro-architectural structure of the femur in the О120+ group of rats was close to that of the О30 sample, which serves as a model of the early stage of osteoporosis (SMI 1.42±0.07; TbPf 5.55±0.28 1/mm). The percentage of bone resorption perimeter and the number of osteoclasts in the О120+ femoral trabeculae were lower than in the О120 group. In the О120+ group, active osteoblasts were observed in a significant part of the resorption cavities. Cell differentiation more was observed in the osteogenic direction than in the adipogenic direction. Conclusion. Bread enriched with protein, fiber, calcium, iron and iodine, effectively weakens osteoporosis induced by ovariectomy in rats. Its inclusion in the diet may be beneficial for the prevention and treatment of systemic postmenopausal osteoporosis.

Enzymatic preparation of Crassostrea oyster peptides and their promoting effect on male hormone production

Ethnopharmacological relevanceCrassostrea gigas Thunberg and other oysters have been traditionally used in China as folk remedies to invigorate the kidney and as natural aphrodisiacs to combat male impotence. Aim of the studyErectile dysfunction (ED) has become a major health problem for the global ageing population. The aim of this study is therefore to evaluate the effect of peptide-rich preparations from C. gigas oysters on ED and related conditions as increasing evidence suggests that peptides are important bioactive components of marine remedies and seafood. Materials and methodsCrassostrea oyster peptide (COP) preparations COP1, COP2 and COP3 were obtained from C. gigas oysters by trypsin, papain or sequential trypsin-papain digestion, respectively. The contents of testosterone, cyclic adenosine monophosphate (cAMP) and nitric oxide (NO) and the activity of nitric oxide synthase (NOS) in mice and/or cells were measured by enzyme-linked immunosorbent assays. Real-time PCR was used to assess the expression of genes associated with sex hormone secretion pathways. The model animal Caenorhabditis elegans was also used to analyze the gene expression of a conserved steroidogenic enzyme. In silico analysis of constituent peptides was performed using bioinformatic tools based on public databases. ResultsThe peptide-rich preparation COP3, in which >95% peptides were <3000 Da, was found to increase the contents of male mouse serum testosterone and cAMP, both of which are known to play important roles in erectile function, and to increase the activity of mouse penile NOS, which is closely associated with ED. Further investigation using mouse Leydig-derived TM3 cells demonstrates that COP3 was able to stimulate the production of testosterone as well as NO, a pivotal mediator of penile erection. Real-time PCR analysis reveals that COP3 up-regulated the expression of Areg and Acvr2b, the genes known to promote sex hormone secretion, but not Fst, a gene involved in suppressing follicle-stimulating hormone release. Furthermore, COP3 was also shown to up-regulate the expression of let-767, a well-conserved C. elegans gene encoding a protein homologous to human 17-β-hydroxysteroid dehydrogenases. Preliminary bioinformatic analysis using the peptide sequences in COP3 cryptome identified 19 prospective motifs, each of which occurred in more than 10 peptides. ConclusionsIn this paper, Crassostrea oyster peptides were prepared by enzymatic hydrolysis and were found for the first time to increase ED-associated biochemical as well as molecular biology parameters. These results may help to explain the ethnopharmacological use of oysters and provide an important insight into the potentials of oyster peptides in overcoming ED-related health issues.