GnRH Receptor Research Articles

Effect of GnRH immunocastration on immune function in male rats.

The present study aimed to reveal the effects of immunocastration on the development of the immune system in rats. Seventy rats were randomly assigned into two groups: Control (n = 35) and immunized (n = 35). Twenty-day-old rats were immunized with gonadotropin-releasing hormone (GnRH) and booster immunization was administered every two weeks (three immunizations in total). From 20-day-old rats, we collected samples every two weeks, including five immunized rats and five control rats (seven collections in total). We collected blood samples, testicles, thymuses, and spleens. The results showed that GnRH immunization increased the GnRH antibody titers and reduced the testosterone concentration (both P < 0.05). Compared with the control group, the number of CD4+CD8- cells, CD4-CD8+ cells, and CD4+CD8+ cells increased (P < 0.05) whereas the number of CD4-CD8- cells and CD4+CD25+ cells reduced in the immunized group (P < 0.05) over time. GnRH immunization also increased the relative weights of thymus and spleen (P < 0.05), serum concentrations of interleukin (IL)-2, IL-4, IL-6, IL-10, IL-17 and Interferon-γ (IFN-γ) over time (P < 0.05), and changed the mRNA levels of IL-2, IL-4, IL-6. IL-10, IL-17, IFN-γ, CD4, D8, CD19 GnRH, and GnRH receptor (GnRH-R) in thymus and spleen. Thus, GnRH immunization enhanced the immune markers in thymus, spleen, and blood immune cytokines in rats.

Association of Gonadotropin-Releasing Hormone Receptor (GnRHR) gene (c.18085 T&gt;G) and litter size in Ettawa crossbreed goat

In the present study, the association of Gonadotropin-Releasing Hormone Receptor gene (GnRHR) and litter size were investigated using the PCR-RFLP method as a genetic marker candidate for litter size in 35 individuals from Ettawa crossbreed goats. This research has two steps conducted in the laboratory and in the field. Data on litter size and blood samples were collected from the field. In the laboratory was carried out DNA isolation, amplification, and restriction. Molecular analysis of DNA isolation were precise, the enzyme Msp1 (C*CGG) with a product length of 706 bp was used for amplification and restriction analysis, releaved TT genotype in GnRHR gene fragment. In the exon 3 of chromosome 6, the single nucleotide polymorphism (SNP) c.18085 T&gt;G was found. Ettawa crossbreed goat in calculations using the hardy-weinberg law, insignificant results are obtained because the value is more than &gt; 0.05 (db; 1) = 0.50. The genotypes and allele frequencies found in the Ettawa Crossbreed Goat GnRHR genes are monomorphic and the GnRHR gene did not associate with litter size. The conclusion is that GnRHR exon 3 gene (SNP) c.18085 T&gt;G did not associate with litter size and can not be used as a genetic marker on Ettawa crossbred goats.

Anti-GnRH Receptor Monoclonal Antibody, GHR106 is First-inClass GnRH Antagonist

During the last decade, a monoclonal antibody, GHR106 was generated and characterized extensively biologically and immunologically. This antibody targets specific human pan cancer marker and is being evaluated for potential therapeutic applications in cancer immunotherapy and fertility regulations. GHR106 was generated against N1-29 oligopeptide located in the extracellular domains of human GnRH receptor found either in the anterior pituitary or in most of cancer cells. In vitro culture of cancer cells revealed that this antibody can induce apoptosis of cancer cells following 24-48 hours incubations. Anti-tumor activities of GHR106 were evaluated by typical nude mouse experiments in which the effective volume reduction of implanted tumor was observed. Humanized forms of GHR106 were made available in CAR (chimeric antigen receptor) T-cell constructs. GHR106 was shown separately to induce cytotoxic killings of cancer cells in vitro by releasing cytokines following incubations of tumor cells with CAR-T cell constructs. In addition, GHR106 also acts as GnRH antagonist by a specific targeting to pituitary GnRH receptor for reversible suppressions of reproductive hormones. These were demonstrated in “Proof of Concept” rabbit experiments. A single subcutaneous injection with 1-3mg/kg of GHR106 to rabbits of either sex could result in 60 to 90% reductions of gonadotropins, estrogen and/or testosterone over a period of one to two weeks. Based on these preclinical assessments, it can be concluded that GHR106 is restricted in tissue expressions and suitable for cancer immunotherapy. It can also act as long-acting GnRH antagonist to target specifically on GnRH receptor in anterior pituitary for numerous gynecological diseases including ovulation inhibition in IVF/ART, endometriosis-premenstrual syndrome, precocious puberty, uterine fibroids and/or polycystic ovarian syndrome.

Targeted Imaging of Endometriosis and Image-Guided Resection of Lesions Using Gonadotropin-Releasing Hormone Analogue-Modified Indocyanine Green

Objective. In this study, we utilized gonadotropin-releasing hormone analogue-modified indocyanine green (GnRHa-ICG) to improve the accuracy of intraoperative recognition and resection of endometriotic lesions. Methods. Gonadotropin-releasing hormone receptor (GnRHR) expression was detected in endometriosis tissues and cell lines via immunohistochemistry and western blotting. The in vitro binding capacities of GnRHa, GnRHa-ICG, and ICG were determined using fluorescence microscopy and flow cytometry. In vivo imaging was performed in mouse models of endometriosis using a near-infrared fluorescence (NIRF) imaging system and fluorescence navigation system. The ex vivo binding capacity was determined using confocal fluorescence microscopy. Results. GnRHa-ICG exhibited a significantly stronger binding capacity to endometriotic cells and tissues than ICG. In mice with endometriosis, GnRHa-ICG specifically imaged endometriotic tissues (EMTs) after intraperitoneal administration, whereas ICG exhibited signals in the intestine. GnRHa-ICG showed the highest fluorescence signals in the EMTs at 2 h and a good signal-to-noise ratio at 48 h postadministration. Compared with traditional surgery under white light, targeted NIRF imaging-guided surgery completely resected endometriotic lesions with a sensitivity of 97.3% and specificity of 77.8%. No obvious toxicity was observed in routine blood tests, serum biochemicals, or histopathology in mice. Conclusions. GnRHa-ICG specifically recognized and localized endometriotic lesions and guided complete resection of lesions with high accuracy.

Mechanism of LH release after peripheral administration of kisspeptin in cattle.

Kisspeptin modulates GnRH secretion in mammals and peripheral administration of 10-amino acid fragment of kisspeptin (Kp10) induces LH release and ovulation in cattle. Experiments were done to determine if iv administration of kisspeptin will activate GnRH neurons (i.e., after crossing the blood-brain barrier) and if pre-treatment with a GnRH receptor blocker will alter kisspeptin-induced LH release (from gonadotrophs) and ovulation. In Experiment 1, cows (n = 3 per group) were given human-Kisspeptin10 (hKp10; 3 x 15 mg iv at 60-min intervals) or normal saline and euthanized 150 min after treatment was initiated. Every 20th free-floating section (50 μm thickness) from the preoptic area to hypothalamus was double immunostained to colocalize GnRH- (DAB) and activated neurons (cFOS; Nickel-DAB). Kisspeptin induced plasma LH release from 15 to 150 min (P = 0.01) but the proportion of activated GnRH neurons did not differ between groups (5.8% and 3.5%, respectively; P = 0.11). Immunogold electron microscopy detected close contacts between kisspeptin fibers and GnRH terminals in the median eminence. In Experiment 2, pubertal heifers (n = 5 per group) were treated with 1) hKp10 iv, 2) Cetrorelix (GnRH antagonist; im) + hKp10 iv or 3) saline on Day 6 of the follicular wave under low-progesterone condition. A rise in plasma LH concentration was detected from 15 to 240 min in the hKp10 group but not in cetrorelix or control group (P<0.001). Ovulations were detected only in the hKp10 group (4/5; P = 0.02). Cetrorelix treatment was associated with regression of the preovulatory dominant follicle and emergence of a new follicular wave 3.4±0.75 days after the treatment in all five heifers. Results support the hypothesis that the effect of peripheral kisspeptin is mediated downstream of GnRH synthesis and does not involve GnRH-independent LH release from gonadotrophs. Peripheral kisspeptin may release pre-synthesized GnRH from the nerve terminals in areas outside the blood-brain barrier.

Effects of benzo[a]pyrene on the reproductive axis: Impairment of kisspeptin signaling in human gonadotropin-releasing hormone primary neurons

The neuroendocrine control of reproduction is strictly coordinated at the central level by the pulsatile release of gonadotropin-releasing hormone (GnRH) by the hypothalamic GnRH neurons. Alterations of the GnRH-network, especially during development, lead to long-term reproductive and systemic consequences, also causing infertility. Recent evidence shows that benzo[a]pyrene (BaP), a diffuse pollutant that can play a role as an endocrine disruptor, affects gonadal function and gamete maturation, whereas data demonstrating its impact at hypothalamic level are very scarce. This study investigated the effects of BaP (10 μM) in a primary cell culture isolated from the human fetal hypothalamus (hfHypo) and exhibiting a clear GnRH neuron phenotype. BaP significantly decreased gene and protein expression of both GnRH and kisspeptin receptor (KISS1R), the master regulator of GnRH neuron function. Moreover, BaP exposure increased phospho-ERK1/2 signaling, a well-known mechanism associated with KISS1R activation. Interestingly, BaP altered the electrophysiological membrane properties leading to a significant depolarizing effect and it also significantly increased GnRH release, with both effects being not affected by kisspeptin addition. In conclusion, our findings demonstrate that BaP may alter GnRH neuron phenotype and function, mainly interfering with KISS1R signaling and GnRH secretion and therefore with crucial mechanisms implicated in the central neuroendocrine control of reproduction.

Testis- specific Y-encoded- like protein 1 and cholesterol metabolism: Regulation of CYP1B1 expression through Wnt signaling.

The cytochromes P450 (CYPs) represent a large gene superfamily that plays an important role in the metabolism of both exogenous and endogenous compounds. We have reported that the testis-specific Y-encoded-like proteins (TSPYLs) are novel CYP gene transcriptional regulators. However, little is known of mechanism(s) by which TSPYLs regulate CYP expression or the functional consequences of that regulation. The TSPYL gene family includes six members, TSPYL1 to TSPYL6. However, TSPYL3 is a pseudogene, TSPYL5 is only known to regulates the expression of CYP19A1, and TSPYL6 is expressed exclusively in the testis. Therefore, TSPYL 1, 2 and 4 were included in the present study. To better understand how TSPYL1, 2, and 4 might influence CYP expression, we performed a series of pull-downs and mass spectrometric analyses. Panther pathway analysis of the 2272 pulled down proteins for all 3 TSPYL isoforms showed that the top five pathways were the Wnt signaling pathway, the Integrin signaling pathway, the Gonadotropin releasing hormone receptor pathway, the Angiogenesis pathway and Inflammation mediated by chemokines and cytokines. Specifically, we observed that 177 Wnt signaling pathway proteins were pulled down with the TSPYLs. Subsequent luciferase assays showed that TSPYL1 knockdown had a greater effect on the activation of Wnt signaling than did TSPYL2 or TSPYL4 knockdown. Therefore, in subsequent experiments, we focused our attention on TSPYL1. HepaRG cell qRT-PCR showed that TSPYL1 regulated the expression of CYPs involved in cholesterol-metabolism such as CYP1B1 and CYP7A1. Furthermore, TSPYL1 and β-catenin regulated CYP1B1 expression in opposite directions and TSPYL1 appeared to regulate CYP1B1 expression by blocking β-catenin binding to the TCF7L2 transcription factor on the CYP1B1 promoter. In β-catenin and TSPYL1 double knockdown cells, CYP1B1 expression and the generation of CYP1B1 downstream metabolites such as 20-HETE could be restored. Finally, we observed that TSPYL1 expression was associated with plasma cholesterol levels and BMI during previous clinical studies of obesity. In conclusion, this series of experiments has revealed a novel mechanism for regulation of the expression of cholesterol-metabolizing CYPs, particularly CYP1B1, by TSPYL1 via Wnt/β-catenin signaling, raising the possibility that TSPYL1 might represent a molecular target for influencing cholesterol homeostasis.

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.

GnRH agonists in the treatment of symptomatic endometriosis: a review

The development of highly potent gonadotropin-releasing hormone agonists (GnRHa) allowed for a significant addition to options for the medical management of symptomatic endometriosis. Pituitary GnRH receptor down-regulation leads to a hypogonadotropic and secondary hypoestrogenic state resulting in lesion regression and symptom improvement. There may be an additional effect of these agents on the inflammatory processes associated with endometriosis as well. This is a review of critical milestones in the clinical application of these agents. Most initial trials of various GnRHa employed danazol as a control and demonstrated general equivalence in reducing symptoms and extent of lesions but without hyperandrogenic side effects and adverse metabolic changes induced by the latter. Short-acting GnRHa is administered intranasally or subcutaneously. Longer-acting preparations are administered intramuscularly or as subcutaneous implants. GnRHa also decrease symptom recurrence rates after surgical management. The hypoestrogenic side effects, including bone mineral density loss and vasomotor symptoms, have limited the duration of use of these agents alone to six months. The use of an appropriate add-back allows for the mitigation of side effects while maintaining efficacy and allowing extension of use for up to 12 months. There is a limited amount of data regarding the use of GnRHa in adolescents out of concern for the effect on developing bone. These agents should be used with caution in this group. The lack of dose flexibility, need for parental administration, and side effect profiles represent drawbacks to GnRHa use. The development of oral GnRH antagonists with short half-lives, variable dosing, and decreased side effects represents an exciting alternative.

GNRHR-related central hypogonadism with spontaneous recovery – case report

BackgroundCongenital hypogonadotropic hypogonadism (CHH) is a clinically and genetically heterogeneous disease characterized by absent or incomplete puberty and infertility. Clinical characteristics are secondary to insufficient gonadotropin secretion, caused by deficient gonadotropin-releasing hormone (GnRH) production, secretion, or action. Loss-of-function variants of the gonadotropin-releasing hormone receptor (GNRHR) are associated with CHH without anosmia. CHH was previously considered a permanent condition, but in the past two decades, cases of spontaneous recovery of CHH have been reported. The reversal of hypogonadism in CHH is currently unpredictable, and can happen unnoticed.Case presentationThe male proband was diagnosed with CHH due to compound heterozygosity for two previously reported pathogenic missense variants in the GNRHR gene, NM_000406.2:c.416G > A (NP_000397.1:p.Arg139His) and c.785G > A (p.Arg262Gln) at 16 years of age. In addition to arrested partial puberty, he had a low testosterone level, gonadotropins in the range of early puberty, and a normal inhibin B level. A therapy with increasing doses of intramuscular testosterone undecanoate was received for 2.5 years, while there was no change in testicular volume. At the age of 19 years, testosterone supplementation was interrupted. During the next two years, he had spontaneous pubertal development to achieve a testicular volume of 20 mL, with normal adult levels of gonadotropins and testosterone.ConclusionsGenetic diagnostics can help discriminate congenital hypogonadotropic hypogonadism, deserving therapeutic intervention, from the self-limited constitutional delay of growth and puberty (CDGP). Patients with GNRHR associated hypogonadism can experience spontaneous recovery of the hypothalamic-pituitary–gonadal axis. Spontaneous testis enlargement in patients with central hypogonadism not taking gonadotropins or pulsatile GnRH therapy can indicate recovery of hypogonadism.

A Flippase-Like Domain-Containing Protein From Deltaproteobacteria Bacterium (Marine Sediment Metagenome) Has Anti-prostate Cancer Effects

Background: Prostate cancer is the second prevalent cancer and the fifth cause of deaths related to the men malignancies. The cancerous cell can travel from prostate to other parts of the body and cause metastasis in other organs such as bones and lymph nodes. For the treatment of the prostate cancer, chemotherapy and hormone therapy are being used. Hormone therapy in this disease is primarily based on the androgen suppression to prevent the growth and division of the cancerous cells. Different classes of drugs are used for hormone therapy. One group of these drugs is reducers of androgen production in adrenal glands. These drugs prevent the androgen production in adrenal glands and cancerous cells. Leuprorelin which is also known as leuprolide is a synthetic peptide that is used for treatment of prostate cancer. Objectives: The aim of this study is to explore novel anti-prostate cancer compounds using proteomics of microorganisms. Methods: Leuprorelin synthetic peptide was chosen as the template for amino acid sequence homology search using blast, and the resulting protein of the best candidate sequences were employed as a query to perform docking test against the gonadotropin-releasing hormone receptor (GRHR) using HDOCK web server. Results: By employing an in silico approach, natural products with structure and function similar to leuprorelin were explored, and their features were characterized. A flippase-like domain-containing protein from Deltaproteobacteria bacterium showed strong binding to gonadotropin-releasing hormone receptor GRHR with docking score of -425. The absorption, distribution, metabolism, and excretion (ADME) tests showed no potential toxicity of this natural product to the body. Conclusion: The present study demonstrated that the proteomics of living organisms contains natural compounds that can be considered a valuable source of medically important resources.

Cardiovascular complications of treatment for prostate cancer.

Prostate cancer, an androgen-dependent disease, is one of the leading causes of mortality in men. It can present as localised disease, locally advanced or distant metastatic disease. Treatment options for patients with prostate cancer include surgery, chemotherapy, brachytherapy, radiation therapy and hormonal therapy. There are multiple treatment options for each stage of the disease, but hormone therapy is usually reserved for advanced stages. Cardiovascular disease is the leading cause of death in patients with prostate cancer and both diseases share common risk factors. Hormone therapy improves prognosis in patients with more advanced disease, albeit at the cost of cardiovascular toxicity. Hormone therapy can be achieved with the use of agonists and antagonists of gonadotropin-releasing hormone receptors, androgen receptor blockers and enzyme inhibitors of androgen synthesis. Drug-specific cardiotoxicity caused by treatments for prostate cancer has not been fully elucidated. Cardiovascular disease in patients with prostate cancer is mainly managed via an ABCDE approach, a strategy to optimise common risk factors. With newer agents improving the prognosis for patients with prostate cancer, cardiovascular toxicity will have a greater impact on the outcomes of these patients. This article reviews cardiovascular risks associated with therapy for prostate cancer with a focus on hormonal therapy.

OR17-3 Immortalized AVPV Kisspeptin Neurons Transiently Express GnRH Receptors under Specific Sex Steroid Conditions in vitro

Abstract In female animals, ovarian estradiol (E2) acts as negative feedback inhibition of GnRH secretion and positive feedback stimulation at ovulation. Both E2-regulated mechanisms work via stimulation or repression of distinct neuronal populations of Kisspeptin (KP)-synthesizing neurons. While E2 clearly stimulates AVPV KP neurons to increase kiss1 expression during the preovulatory surge, mechanisms required for optimal potentiation of maximal GnRH surge release remain incompletely characterized. We used two immortalized KP cell lines demonstrating increased kiss1 expression under high E2 (KTaV-3), or kiss1 suppression under low E2 (KTaR-1), to probe GnRH receptor (GnRHR) expression levels under E2 conditions of varying doses and times of exposure. Additionally, we have begun to investigate transcriptional mechanisms underlying gnrhr expression in KP neurons in vitro. AVPV-derived KTaV-3 cells were treated with either E2 alone (5-100pM) or E2 with progesterone (4-40nM) for varying durations (4-96h), either constitutively or under modulating levels approximating changes found during the murine estrous cycle. All treatments were undertaken in serum-free (SF) media (DMEM) following a 50% serum synchronization. After total RNA isolation, cDNAs were probed with mouse gnrhr primers. Results reveal that gnrhr expression, not observed in typical growth media conditions, is induced in KTaV-3 cells to varying degrees dependent on prior E2/P4 exposure. Following shorter treatment times (12-24h), proestrus levels (100pM E2; 4nM P4) of sex steroids noticeably induced gnrhr, while exposure of KTaV-3 cells to a 96h estrous cycle revealed maximal gnrhr expression at the diestrus II→proestrus transition, with exposure cycles concluding with declining E2/rising P4 exhibiting no to minimal gnrhr expression. These results suggest that maximal KP neuronal expression of gnrhr may occur prior to the E2 peak on proestrus, potentially preparing AVPV KP neurons for GnRH surge release 12-16h later. Similar steroid conditions also increased dlx3 expression, a transcription factor required for GnRHR in pituitary, only in KTaV-3 cells. In KTaR-1 cells, gnrhr expression was observed only following E2 decreases, while dlx3 was constitutively elevated. Since cFos/JunB complex formation on the gnrhr promoter has been implicated in gonadotrope GnRHR levels, we explored how transfection of these transcription factors might affect gnrhr expression in KTaV-3 cells. Preliminary results reveal that fos/jun co-transfection stimulates gnrhr expression maximally at intermediate (DII) E2 levels, while higher E2 levels are required with fos or jun expression alone. While reciprocal GnRH-Kisspeptin connections have not yet been observed in vivo, these results suggest KP neurons may possess the capacity to respond to intrahypothalamic GnRH only in certain estrous cycle stages, by differentially modulating GnRH receptivity in the AVPV. These findings supplement the prevailing model of feed-forward KP regulation of GnRH with potential short-loop KP-GnRH positive feedback regulation, providing an increased understanding of feedback mechanisms required for normal neuroendocrine regulation of reproduction. Presentation: Sunday, June 12, 2022 11:30 a.m. - 11:45 a.m.

ODP400 A Mutation in the Gonadotropin Releasing Hormone Receptor Associated with Congenital Hypogonadotropic Hypogonadism with Absence of Uterus and Ovaries

Abstract Introduction Mutations in the GNRH receptor may result in congenital hypogonadotropic hypogonadism (CHH) due to a deficiency in gonadotropins. Both autosomal dominant and recessive transmission patterns have been described. In young women, this presents with primary amenorrhea and a failure to progress through puberty with their peers. Here we present a case of CHH in a woman found to have a mutation in the GNRH receptor. Clinical Case A 24-year-old woman with no significant medical history presented to the endocrine clinic for the evaluation of primary amenorrhea and infertility. The patient had recently migrated to the U. S. from Guatemala. She was well appearing with Tanner stage 2 breast and pubic hair development. Normal external genitalia and vagina were noted without anosmia. Her family history was significant for delayed puberty in her mother, primary amenorrhea and delayed puberty in her 22-year old sister and a 16-year old brother who underwent puberty with his peers. The patient was unaware of any other family members with similar symptoms. Laboratory data revealed Prolactin 9.47 ng/ml (4.79-23.3),FSH 0.6*, LH 0.1*, estradiol &amp;lt;5. 0 pg/ml*, Total testosterone 6.2 ng/dl(10-55), Free testosterone 0.3 pg/ml (0-4.2), TSH 1.88 U/L (0.47-6.90), Free T4 1.14 ng/dl(7.5-2. 0),IGF1 302 ng/ml(100-311) Cortisol 7.6 ug/dl (6.9-29), ACTH 17 pg/ml (7.2-63.3), 17 OHP 10 ng/dl* [(*) Low ]. MRI of the sella revealed a normal pituitary. Pelvic ultrasound revealed absence of uterus and ovaries. A CT of the pelvis confirmed the absence of uterus and ovaries and noted a normal vagina with partial cervix. Karyotype revealed a 46XX pattern with multiple regions of homozygosity suggesting shared ancestry between her parents. Further testing revealed ahomozygous mutation in the GNRH receptor c.247C&amp;gt;G (p. Leu 83Val),classified as a variant of unknown significance. Testing was offered for her sister and other first-degree family members but was declined as they reside in Guatemala. Low dose estrogen therapy delivered by transdermal routewas initiated. She was referred to a geneticist and counseled on the impact of her diagnosis and the absence of uterus and ovaries on fertility. Psychological support was offered. Conclusion This is the first reported case of a GNRH receptor mutation associated with primary amenorrhea and the complete absence of uterus and ovaries. Testing first-degree relatives is necessary to clarify its role in the above phenotype, and its mode of inheritance. Referral to a geneticist and specialists in difference of sex development (DSD) is a cornerstone of therapy in CHH. In women, treatment involves the induction of puberty with gradually escalating doses of estrogen, followed by the addition of progesterone in those patients with an intact uterus. Ovulation induction with gonadotropin therapy may be considered in appropriate patients with CHH, if fertility is desired. Presentation: No date and time listed

PMON29 A Comparative Analysis of Musashi-Dependent Control of Mouse and Human Pituitary mRNA Translation

Abstract Specialized cell lineages within the anterior pituitary produce specific hormones which, in turn, regulate diverse biological processes ranging from growth, metabolism, and reproduction to stress. Interestingly, these specialized cell lineages exhibit a high degree of cellular plasticity, readily altering their differentiation state to produce different hormones in response to organismal demand. Underlying molecular mechanisms controlling cellular plasticity in the pituitary are not fully defined but appear to involve post-transcriptional regulation exerted by the Musashi family of sequence-specific RNA binding proteins. Musashi is a bifunctional regulator of target mRNAs and can exert either repression or activation of translation in a context-dependent manner. Our recent work has implicated a role for Musashi-dependent repression of key pituitary mRNAs in the mouse, including a lineage-specific transcription factor (Pou1f1), the gonadotropin releasing hormone receptor (Gnrhr), and two anterior pituitary hormones (Prl and Tshb). In this study, we look to determine the potential relevance of Musashi-dependent mRNA translational control to the human pituitary. Reflecting our findings in the adult mouse, a re-analysis of published human fetal pituitary single cell RNA sequencing data revealed Musashi1 (MSI1) and Musashi2 (MSI2) expression in both stem/progenitor cell populations as well as in all hormone-producing cell lineages of the anterior pituitary. We further report that the human homologs of identified Musashi-target mRNAs in the mouse pituitary also possess Musashi binding elements (MBEs) in their 3' untranslated regions (UTRs). In the case of the human Pou1f1 3' UTR, we were able to verify Musashi-dependent mRNA translational repression in reporter assays as seen with the murine Pou1f1 3' UTR. Interestingly, a germline Pou1f1 mutation identified in human patients, disrupts a consensus MBE in the human Pou1f1 3' UTR and abolishes Musashi-dependent repression. We developed a bioinformatic pipeline to characterize pathogenic human mutations catalogued in the Geno2MP database for disruption or creation of consensus MBEs in pituitary-specific mRNA 3' UTRs. Our findings suggest an evolutionarily conserved role for Musashi in the post-transcriptional regulation of pituitary mRNAs in both mice and humans and identify several human mutations which may perturb Musashi regulation of human pituitary function. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

PMON56 LH synthesis is regulated by RNA-binding protein ZFP36 bound with AU-rich elements in gonadotropes

Abstract Gonadotropin secretion, which is stimulated by gonadotropin-releasing hormone (GnRH), is a critical feature of reproductive control and maintenance of fertility. GnRH stimulation increases LH secretion 50-100-fold over baseline per pulse, whereas Lhb gene expression increases a modest 1.4-fold. This observation shows that significant post-transcriptional regulation of gonadotropin synthesis and secretion must occur. We have previously shown that GnRH-induced Dusp1 expression, a factor central for feedback control of GnRH signaling in gonadotropes, depends on interaction of the 3'UTR of its mRNA with the RNA binding protein (RBP) ELAVL1, which binds AU-rich elements (ARE) in target mRNAs (1). Recently, using RIP-Chip analysis, we have shown that GnRH receptor (Gnrhr) expression depends on interaction of its mRNA with ELAVL1. Gnrhr mRNA is among the most highly represented ELAVL1-associated mRNAs (2). Further, many mRNAs encoding proteins essential to gonadotropin gene expression, including the immediate-early transcription factor genes Egr1, 2, and 4, Fos, Fosb, Jun, and Junb, as well as Dusp1 and 2, show increased binding to ELAVL1 after GnRH treatment, although gonadotropin Lhb mRNA is not, due to the absence of ARE site to be bound. Typically, association with ELAVL1 stabilize expression of target mRNAs, promoting their translation. Also, of interest is the role of the RBP ZFP36, which competes with ELAVL1 for binding to ARE's but has the opposing effect of directing mRNA to the degradation pathway. Significantly, 5 minutes pulsatile GnRH stimulated ZFP36 protein production in 30-60 minutes in LbetaT2 cells. And, knockdown of ELAVL1 results in the deterioration of Gnrhr expression and of the immediate-early gene Egr1 a transcription factor central to Lhb expression. We have examined the direct role of ZFP36 protein in GnRH-induced gene expression. Interestingly, Gnrhr and Lhb mRNA expression levels were decreased by ZFP36 overexpression in LbetaT2 cells compared with control cells. Also, GnRH-stimulated EGR1 production by was decreased by ZFP36 overexpression. These observations are consistent with previous results with ELAVL1 knockdown showing decreased mRNA stability. We cloned Egr1, Gnrhr and Zfp36 3'UTRs which contain AREs bound by ELAVL1 into luciferase reporter genes in pmirGLO vector to evaluate whether the 3'UTR is directly affected by ZFP36. These Egr1, Gnrhr and Zfp36 3'UTR contained mirGLOs were transfected in both ZFP36 overexpression and control cells and luciferase activity was monitored. The results showed that luciferase expression from reporters bearing the target 3'UTR were significantly reduced in ZFP36 overexpressed cells. Collectively, our studies show that ELAVL1, ZFP36 and their target mRNAs are regulated by GnRH and this indirectly regulates Lhb gene expression in gonadotropes. ) Do MT, T Kim et al. Mol Cell Endocrinology 382 (1): 1346-1357, 2014 ) Terasaka T et al. Endocrinology 160(8): 1999-2014, 2019 Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

PMON55 Calcium Imaging in the Intact Mouse Pituitary: A Novel Design for Understanding the Formation and Modulation of the Gonadotrope Network

Abstract The reproductive cells of the pituitary, the gonadotropes, develop after e12.75 in mice and continue to differentiate and migrate throughout puberty. In response to physiological signals, these cells change in morphology to alter connections with other cells. Previous studies have indicated that gonadotropes have functional relationships in an interconnected, organized network. However, little work has been done to determine (1) what developmental cues are needed to organize this network, or (2) how this network functions to promote gonadotropin secretion. Activation of gonadotropin-releasing hormone receptors (GnRHRs) leads to an increase in intracellular calcium; therefore, this pathway can be used for visualizing the activation of gonadotropes. We have developed a novel system to analyze the gonadotrope network which will allow us to study the influence of physiological signals to this interconnected population. To visualize calcium signals specifically in gonadotropes, we created a line of Gonadotrope-GCaMP mice using Gnrhr-driven Cre to express the GCaMP calcium indicator. For present studies, intact pituitary glands were taken from adult Gonadotrope-GCaMP mice (males and proestrous females). Whole pituitaries were mounted in a chamber, and gonadotrope network responses to GnRH (1 or 5nM, at least 4 pituitaries/dose) were recorded using confocal microscopy. Calcium signals from an average of 177 ± 8 gonadotropes per pituitary were analyzed. MATLAB software was used to quantify network connections of gonadotropes for each treatment. Correlation coefficients were determined by their patterns of calcium signaling. Gonadotrope connectivity increases following GnRH stimulation in a dose-dependent manner in female pituitaries (17% following 1nM GnRH, p&amp;lt;0.05; 44% following 5nM GnRH, p&amp;lt;0.05). While male gonadotropes also increase connectivity following stimulation with GnRH, the effect is not enhanced by the higher dose (27% following 1nM GnRH, p&amp;lt;0.05; 20% following 5nM GnRH, NS). Although the strength of gonadotrope correlations is not changed by 1nM GnRH in females, higher dosage of GnRH doubles the strength of correlations over pre-stimulation levels (Pre: 0.08, Post: 0.16, p&amp;lt;0.05). The strength of correlations in males was not significantly altered by GnRH at either dose. In conclusion, the data from whole mouse pituitaries confirm that gonadotropes are capable of high levels of coordinated activity. All pituitaries showed baseline levels of coordination among gonadotropes, confirming the presence of the network. Network activation is significantly increased by GnRH stimulation in both males and females. In females, coordination of gonadotropes is also strengthened by GnRH in a dose-dependent manner. Using a novel gonadotrope-specific calcium indicator mouse model, we have shown GnRH-mediated changes in gonadotrope network connectivity in the intact mouse pituitary. Future studies in our lab will determine how other physiological signals are involved in development and/or maintenance of this coordinated activation. Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

Prolonged Disease-Free Survival in a Relapsed Adult Granulosa Cell Tumor of the Ovary Treated by Combined Leuprolide and Letrozole: Case Report

Relapsing ovarian granulosa-cell tumor (GCT) is a challenge for physicians due to the lack of effective therapy. Current strategies did not improve the 80% death rate of recurrent disease. GCTs synthesize estrogens and express follicle-stimulating hormone, gonadotropin-releasing hormone, and estrogen and progesterone receptors. The FOXL2-C134W mutation is shared in all GCTs, and its downregulation of hormone-related apoptosis appears causal in induction of tumor phenotype. On these assumptions, hormone anti-estrogenic therapies have been proposed for recurrent GCTs. A 32-year-old woman suffering from GCT was first treated by surgery in 2004 and staged as IA disease. Two subsequent pelvic relapses were diagnosed in 2006 and 2007, and the patient underwent surgery and chemotherapy to treat both recurrences. Overall, she underwent five subsequent surgical interventions and two chemotherapy instances. A third single pelvic relapse above the vaginal cuff was diagnosed in 2013. Based on the patient’s refusal to undergo further surgery we proposed an anti-estrogen therapy consisting of combined GnRH analogue leuprolide and the aromatase inhibitor letrozole. Complete remission was obtained after 3 months from the start of therapy. Subsequently, we found that disease-free survival was maintained over 9 years of treatment. Although recent reports indicate poor effectiveness of hormone therapy to treat recurrent GCTs, the success of this case indicates that a subset of patients with recurrent GCT maintain a tumor phenotype highly responsive to anti-estrogen drugs.

Impulsive time series modeling with application to luteinizing hormone data.

This work considers the estimation of impulsive time series pertaining to biomedical systems and, in particular, to endocrine ones. We assume a signal model in the form of the output of a continuous linear time-invariant system driven by a sequence of instantaneous impulses, which concept is utilized here, in particular, for modeling of the male reproductive hormone axis. An estimation method to identify the impulsive sequence and the continuous system dynamics from sampled measurements of the output is proposed. Hinging on thorough mathematical analysis, the method improves upon a previously developed least-squares algorithm by resolving the trade-off between model fit and input sparsity, thus removing the need for manual tuning of user-defined estimation algorithm parameters. Experiments with synthetic data and Markov chain Monte-Carlo estimation demonstrate the viability of the proposed method, but also indicate that measurement noise renders the estimation problem ill-posed, as multiple estimates along a curve in the parameter space yield similar fits to data. The method is furthermore applied to clinical luteinizing hormone data collected from healthy males and, for comparability, one female, with similar results. Comparison between the estimated and theoretical elimination rates, as well as simulation of the estimated models, demonstrate the efficacy of the method. The sensitivity of the impulse distribution to the estimated elimination rates is investigated on a subject-specific data subset, revealing that the input sequence and elimination rate estimates can be interdependent. The dose-dependent effect of a selective gonadotropin releasing hormone receptor antagonist on the frequency and weights of the estimated impulses is also analyzed; a significant impact of the medication on the impulse weights is confirmed. To demonstrate the feasibility of the estimation approach for other hormones with pulsatile secretion, the modeling of cortisol data sets collected from three female adolescents was performed.

161MO Efficacy and safety of relugolix in Asian men with advanced prostate cancer (APC): A subgroup analysis from the randomized, phase III HERO study versus leuprolide

Although prostate cancer occurrence is relatively low in Asia, incidence and mortality have been rapidly increasing across the continent (Zhu et al. Nat Rev Urol 2021;18:282-301). In the global phase 3 HERO study, relugolix, the once-daily oral gonadotropin-releasing hormone receptor antagonist, demonstrated superior continuous suppression of testosterone to castrate levels through week 48 compared to leuprolide (relugolix:96.7% vs leuprolide:88.8%; difference:7.9% (95% confidence interval [CI], 4.1 to 11.8); Shore et al.