A Peculiar Case of Cabergoline Response to a Non-functioning Cystic Pituitary Adenoma in a Young Adult Male.

We present an interesting case of a cystic, pituitary adenoma that showed up insidiously with non-traditional clinical symptoms. The standard of care for non-functioning pituitary adenomas is transsphenoidal surgery. However, with pharmacotherapy using cabergoline (a dopamine receptor agonist), the patient had a near disappearance of the tumor. This case report seeks to add to the medical literature the possibility of pharmacotherapy for treating non-functional pituitary adenomas.

Androgen inhibition of reproductive neuroendocrine function in females and transgender males.

Ovarian function is controlled by pituitary secretion of luteinizing hormone (LH) and follicle stimulating hormone (FSH), which in turn are governed by gonadotropin releasing hormone (GnRH) secreted from the brain. A fundamental principle of reproductive axis regulation is negative feedback signaling by gonadal sex steroids back to the brain to fine-tune GnRH and gonadotropin secretion. Endogenous negative feedback effects can be mimicked by exogenous steroid treatments, including androgens, in both sexes. Indeed, a growing number of clinical and animal studies indicate that high levels of exogenous androgens, in the typically male physiological range, can inhibit LH secretion in females, as occurs in males. However, the mechanisms by which male-level androgens inhibit GnRH and LH secretion still remain poorly understood, and this knowledge gap is particularly pronounced in transgender men (individuals designated female at birth but identifying as male). Indeed, many transgender men take long-term gender-affirming hormone therapy that mimics male-level testosterone levels. The impact of such gender-affirming testosterone on the reproductive axis, both at the ovarian and neuroendocrine level, is a long-understudied area that still requires further investigation. Importantly, the few concepts of androgen actions in females mostly come from studies of polycystic ovary syndrome which does not recapitulate a similar androgen milieu or a pathophysiology of inhibited LH secretion as occurs in testosterone-treated transgender men. This review summarizes clinical evidence indicating that exogenous androgens can impair neuroendocrine reproductive function in both females and transgender men and highlights emerging experimental data supporting this in recently-developed transgender rodent models.

Zinc Oxide Nanoparticles Induced Testicular Toxicity Through Inflammation and Reducing Testosterone and Cell Viability in Adult Male Rats.

Zinc oxide nanoparticles (ZnO NPs) have wide applications in daily life. Therefore, there is growing interest in the potential harmful impacts of these particles on human health. The present study was conducted to investigate the potential toxic effects of ZnO NPs (40 and 70 nm) compared to ZnO on the testes of rats. ZnO NPs were synthesized and characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Adult male rats were randomly divided into four groups (n = 8): Group I (control), Group II (ZnO) received daily oral administration of ZnO (50 mg/kg), and Groups III and IV received daily oral administration of ZnO NPs of 40 nm or 70 nm at 50 mg/kg, respectively. All treatments continued for 50 consecutive days. ZnO and ZnO NPs reduced body and testis weights, sperm count and motility, serum luteinizing hormone (LH) and testosterone levels, testicular cytochrome p450 17A1 (CYP17A1) and cytochrome p450 1B1 (CYP1B1) concentrations, and the expression of p53 and cdk1. These treatments elevated testicular myeloperoxidase and serum acid phosphatase activities as well as sperm abnormalities. ZnO NPs reduced LH levels, which decreased CYP17A1 and CYP1B1, resulting in reduced synthesis of testosterone. ZnO NPs enhanced testicular inflammation and reduced cell viability. All these effects were manifested as reduced sperm motility and increased sperm deformities. Compared to macromolecules, nanoparticles exhibited significantly higher toxicity. The larger diameter ZnO NPs had more profound toxicity than the smaller-sized particles.

Diagnostic utility of the average peak LH levels measured during GnRH stimulation test.

OBJECTIVES: Gonadotropin-releasing hormone (GnRH) test is the gold standard test to evaluate the hypothalamus-pituitary-gonadal (HPG) axis for the diagnosis of central precocious puberty (CPP). However, the diagnosis of cases with clinical features of CPP whilst have borderline peak LH remain challenges. We aimed to evaluate diagnostic performance of the average of LH levels measured during GnRH stimulation test. METHODS: Cases with diagnosis of CPP and premature thelarche (PT) who had a GnRH stimulation test results were retrospectively reviewed. Anthropometric measurements (weight, height, and body mass index), age and sex-specific standard deviation scores, growth velocity, puberty stages, bone ages, serum FSH, LH, and estradiol levels were measured by electrochemiluminescence immunological method (ECLIA), and the GnRH stimulation test results, which performed by obtaining venous blood samples at basal, 20th, and 40th minutes for FSH and LH measurement, were recorded. RESULTS: A total of 76 girls (38 CPP, 38 PT) were included. We detected an average peak LH cut-off value of 4.25 IU/L with 94.7 % sensitivity and 97.4 % specificity, a 97.3 % positive predictive value, and a 94.9 % negative predictive value in GnRH test to differentiate cases with CPP from PT. CONCLUSIONS: This is the first study evaluating the diagnostic utility of the average of LH levels measured during GnRH stimulation test. We showed that the average of two LH measurements has a high diagnostic performance. Therefore, it can be used as a valid and reliable diagnostic tool for assessment of HPG axis activation, particularly for cases with a borderline peak LH level.

Metallosis-Induced Warm Antibody Auto-Immune Hemolytic Anemia After Bilateral, Large-Diameter Metal-on-Metal Total Hip Arthroplasty With Complete Remission After Revision.

The use of metal-on-metal bearing couples in total hip arthroplasty can lead to an increased release of metal ions, particularly cobalt and chromium over time. This can lead to local and systemic metallosis, which has cytotoxic, genotoxic, and immunotoxic effects and can cause a host of secondary disorders. We describe the case of a 37-year-old female patient that was diagnosed with warm-antibody autoimmune hemolytic anemia (WAIHA) one and a half years after bilateral large-diameter head metal-on-metal total hip arthroplasty. For 11 years, it was refractory to all therapy, including splenectomy and rituximab, requiring long-term oral prednisone for disease control. Ultimately, systemic metallosis and periprosthetic joint infection were diagnosed, requiring explantation of the prostheses. By the sixth week postoperatively, she experienced complete spontaneous remission of her WAIHA. In conclusion, WAIHA can be associated with systemic metallosis in patients with metal-on-metal prosthetic joint replacements. Both hematologists and orthopedic surgeons should be aware of this.

The Impact of Diabetes on Male Silkworm Reproductive Health.

The increasing prevalence of diabetic reproductive complications has prompted the development of innovative animal models. The use of the silkworm Bombyx mori as a model for diabetic reproductive damage shows potential as a valuable research tool. This study employed silkworms as a novel model to investigate diabetic reproductive damage. The silkworms were fed a high-glucose diet containing 10% glucose to induce a diabetic model. Subsequently, the study concentrated on assessing the influence of diabetes on the reproductive system of male silkworms. The results indicate that diabetes resulted in reduced luteinizing hormone (LH) and testosterone (T) levels, as well as elevated triglyceride (TG) levels in male silkworms. Moreover, diabetes mellitus was associated with pathological testicular damage in male silkworms, accompanied by decreased glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) levels, along with increased malondialdehyde (MDA) levels in the testis. Additionally, diabetes mellitus reduced the expression of siwi1 and siwi2 genes in the testis of male silkworms. Overall, these results support using silkworms as a valuable model for studying diabetic reproductive damage.

Endothelin-3 Suppresses Luteinizing Hormone Receptor Expression by Regulating the cAMP-PKA Pathway in Hen Granulosa Cells.

Previous research identified the expression of EDN3 in granulosa cells of preovulatory follicles in chickens. Notably, the expression level of EDN3 in Silky Fowl with low egg-laying performance was significantly higher than that in high-yield laying breed White Leghorn. Given the crucial role of granulosa cells in follicular development and maturation, it is very important to study the effect of EDN3 on the biological function of granular cells. In this study, an EDN3 overexpression plasmid was constructed and transfected into granular cells. The viability of these cells was detected using quantiative (qPCR), Cell Counting Kit-8 (CCK8), and 5-Ethynyl-2'-deoxyuridine (EdU) assays. Gonadal hormone synthesis was detected using enzyme-linked immunosorbent assay (ELISA) techniques. Finally, transcriptome sequencing was employed to identify differentially expressed genes. Result showed thatoverexpression of EDN3 was observed to promote cell viability. In addition, it significantly inhibits the expressions of LHR and cAMP-PKA signaling pathways. Cell transcriptome sequencing data displayed that EDN3 can upregulate energy metabolism and immune-related signaling pathways, whereas follicle maturation and the GnRH signaling pathway were downregulated. In conclusion, this study demonstrates that EDN3 can enhance granulosa cell viability and inhibit the expression of LHCGR, a process likely mediated through the cAMP-PKA signaling pathway. However, further evidence is required to substantiate the regulatory relationship between EDN3 and the cAMP-PKA signaling pathway.

Loss of the long form of Plod2 phenocopies contractures of Bruck syndrome - osteogenesis imperfecta.

Bruck syndrome is an autosomal recessive form of osteogenesis imperfecta (OI) caused by biallelic variants in PLOD2 or FKBP10 and is characterized by joint contractures, bone fragility, short stature, and scoliosis. PLOD2 encodes LH2, which hydroxylates type I collagen telopeptide lysines, a critical step for collagen crosslinking. The Plod2 global knockout mouse model is limited by early embryonic lethality, thus the role of PLOD2 in skeletogenesis is not well understood. We generated a novel Plod2 mouse line modeling a variant identified in two unrelated individuals with Bruck syndrome: PLOD2 c.1559dupC, predicting a frameshift and loss of the long isoform LH2b. In the mouse, the duplication led to loss of LH2b mRNA as well as significantly reduced total LH2 protein. This model, Plod2fs/fs, survived up to E18.5 although in non-Mendelian genotype frequencies. The homozygous frameshift model recapitulated the joint contractures seen in Bruck syndrome and had indications of absent type I collagen telopeptide lysine hydroxylation in bone. Genetically labeling tendons with Scleraxis-GFP in Plod2fs/fs mice revealed the loss of extensor tendons in the forelimb by E18.5 and developmental studies showed extensor tendons developed through E14.5 but were absent starting at E16.5. Second harmonic generation showed abnormal tendon type I collagen fiber organization, suggesting structurally abnormal tendons. Characterization of the skeleton by µCT and Raman spectroscopy showed normal bone mineralization levels. This work highlights the importance of properly crosslinked type I collagen in tendon and bone, providing a promising new mouse model to further our understanding of Bruck syndrome.

Bruck syndrome is a rare disease where individuals have brittle bone as well as contracted or stiff joints. Mutations in two genes are associated with Bruck syndrome and, in this work, we focus on PLOD2. Mice without Plod2 die at an early embryonic stage, before they have a chance to fully develop. In this work, we created a mouse with a PLOD2 mutation seen in people with Bruck syndrome. Some of these new Bruck syndrome model mice survived to a later gestational age, but all died at birth. The Bruck syndrome mice were small and had contracted joints. We found they were missing tendons in their arms and had structurally abnormal tendons in their knees. Bone mineralization was normal, but there were indications that the modifications needed for normal type I collagen structure were absent. Overall, this is an advantageous new mouse model of Bruck syndrome that can be used to study this rare disease and highlights the importance of Plod2 in tendon.

Relationship between inflammatory markers, hormonal profiles, and sperm parameters.

OBJECTIVE: The aim of this study is to evaluate the relationship between semen parameters, complete blood count, and hormone levels on the day of spermiogram. METHODS: Semen parameters of 230 patients who were examined for full blood count test and hormone levels on the day of spermiogram were included in the study. Patients were grouped according to the total motile sperm count (TMSC), semen parameters, hemogram, and hormone levels were compared between groups. RESULTS: No statistically significant difference was found between groups in neutrophil ratios, neutrophil, lymphocyte, platelet counts, neutrophile-to-lymphocyte ratio (N/L), and platelet-to-lymphocyte ratio (P/L). However, white blood cell (WBC) and lymphocyte counts were weakly positively correlated with sperm concentration (p=0.021, p=0.026), and a weakly significant positive correlation was found with WBC and neutrophil count for motility (p=0.038, p=0.004). FSH level was found to be lower in cases with TMSC >20 m than those with TMSC <5 m and 5-10 m (p=0.004, p=0.022). LH was found to be lower in cases with TMSC >20 m than those with TMSC <5 m (p=0.048). A negative correlation was found for both FSH and LH levels with sperm concentration, motility, and TMSC (p<0.001, p=0.014). CONCLUSION: In this study, a significant negative correlation was demonstrated between FSH, LH levels and sperm concentration, motility, TMSC. N/L and P/L cannot be used as predictive markers of sperm quality. The results of a significant positive correlation between WBC, neutrophil counts, and sperm parameters encourage researchers to conduct prospective randomized controlled trials with larger sample sizes and different inflammatory and hormonal markers.

Quantitative detection of pre-ovulatory luteinizing hormone surges in urine using the microfluidic vertical agitation approach.

Identifying the time of ovulation is an important process for women seeking and avoiding pregnancy. Luteinizing hormone (LH) plays an important role in ovulation, which is very important in the reproductive mechanism. Therefore, detecting the LH level is of great importance in monitoring ovulation. In this study, sensitive, rapid and selective electrochemical biosensors were developed to detect LH quantitatively from human urine samples and to monitor the ovulation period. Isopotential region and current density optimization studies revealed that sensors with an electrode width and spacing of 1 mm had the optimum performance. Electrochemical impedance spectra evidenced immobilization of DSP self-assembled monolayers and anti-LH-beta antibody on the surface. While the mobile phone vibrator led to a 3.5-fold enhancement in response signals, the agitation system developed resulted in a 10-fold improvement. The sensors displayed detection limits of 1.02 and 1.53 mIU/ml in the range of 0-40 mIU/ml LH concentration obtained using two statistical approaches. Additionally, the sensors showed no cross-reactivity to hCG, which is very similar in structure and is widely reported to have high cross-reactivity.

Gonadal hormones and metabolic syndrome in middle-aged and elderly males: results from a prospective cohort study in China.

Background: Research has shown that gonadal hormones are involved in metabolic pathways relevant to metabolic syndrome (MetS). Nevertheless, no longitudinal study has been conducted on the association between SHBG and MetS in Chinese. The objective of our study was to determine whether there is any association between middle-aged and elderly males in China. Methods: A total of 531 eligible male subjects, aged above 40 years or older, without MetS at baseline, were recruited. Sex hormone binding globulin (SHBG), total testosterone (TT), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured. A harmonized definition and recommended thresholds for the Chinese population were used to determine metabolic syndrome. Results: During 3.2 years of follow-up, 20.7% of subjects had developed MetS. Compared with the non-MetS group, subjects in the new-onset MetS group had significantly lower SHBG (43.5 nmol/L [28.8, 74.9] vs 53.7nmol/L [33.8, 115.0], P=0.0018), TT (18.1nmol/L [13.6-21.7] vs 19.5nmol/L[15.0-23.6], P=0.0204), and LH (5.13mIU/L [3.63-7.29] vs 5.87mIU/L [4.05-8.36]) at baseline. The incidence of MetS was decreased according to elevated SHBG quartiles (Q1:26.9%, Q2:22.7%, Q3:21.1%, Q4:12.1%, P for trend =0.0035), TT (Q1: 25.2%, Q2:23.7%, Q3: 17.3%, Q4: 16.7%, P for trend=0.0425), and LH (Q1:25.0%, Q2:21.8%, Q3: 21.8%, Q4: 14.3%, P for trend=0.0411). Compared with those in quartile 4, the OR[CI] of incident MetS for participants in Quartile 1 was 2.33[1.13-4.79] after multiple adjustments. But associations between incident MetS and different quartiles of LH, TT, and FSH were not observed after multiple adjustments. In the subgroup analyses, the significant association between SHBG level and Mets was detected in subjects over 60 years or older, with normal BMI, without insulin resistance, and with eGFR ≥90 mL/min per 1.73m2. Conclusion: Compared with TT, LH, and FSH, a lower level of SHBG is significantly related to the incidence of MetS among middle-aged and elderly males in China.

Longitudinal Evaluation of Reproductive Endocrine Function in Men with ACTH-Dependent Cushing Syndrome.

CONTEXT: Hypogonadism may be caused by Cushing syndrome (CS) and may intensify its adverse consequences. OBJECTIVE: To determine the frequency of male hypogonadism before and after curative surgery for CS, and its cause. DESIGN: Post-hoc analyses of prospective cohort studies. SETTING: Clinical research center. PATIENTS: Men with ACTH-dependent CS. Cohort 1 (C1) (n=8, age 32.5±12 y; studied 1985-1989); Cohort 2 (C2) (n=44, 42.7 ± 15.1 y; studied 1989-2021). INTERVENTIONS: C1: Every 20-minute blood sampling for 24h before and 1-40 months after surgical cure. Three subjects underwent GnRH stimulation tests pre- and post-surgery. C2: Hormone measurements at baseline and 6 and 12 months (M) post-cure. MAIN OUTCOME MEASURES: C1: LH, FSH, LH pulse frequency and LH response to GnRH. C2: LH, FSH, testosterone (T), free T, fT4, T3, TSH and UFC levels and frequency of hypogonadism pre- and post-surgery. RESULTS: C1: mean LH and LH pulse frequency increased after surgery (p < 0.05) without changes in LH pulse amplitude, mean FSH, or peak gonadotropin response to GnRH. C2: 82% had baseline hypogonadism (total T 205 ± 28 ng/dL). Thyroid hormone levels varied inversely with UFC and cortisol. LH, total and free T, and SHBG increased at 6M and 12M post surgery, but hypogonadism persisted in 51% at 6M and in 26% at 12M. CONCLUSION: Hypogonadism in men with CS is widely prevalent but reversible in ∼75% of patients one year after surgical cure and appears to be mediated through suppression of hypothalamic GnRH secretion, and modulated by thyroid hormones.

Clinical parameters that predict a premature LH rise in patients undergoing ovarian stimulation for IVF.

Background: Normal reproductive function requires adequate regulation of follicle stimulating hormone (FSH) and luteinizing hormone (LH) secretion. During ovarian stimulation for in-vitro fertilization (IVF), some patients will demonstrate an early rise in LH despite being treated with a gonadotropin releasing-hormone (GnRH) antagonist, sometimes necessitating cycle cancellation. Previous studies have demonstrated a possible link between a premature LH rise with ovarian response to gonadotropins. We sought to determine what clinical parameters can predict this premature LH rise and their relative contribution. Methods: A retrospective study of 382 patients who underwent IVF treatment at Rambam Medical Center. The patients were stratified into age groups. A model predicting premature LH rise based on clinical and demographic parameters was developed using both multiple linear regression and a machine-learning-based algorithm. Results: LH rise was defined as the difference between pre-trigger and basal LH levels. The clinical parameters that significantly predicted an LH rise were patient age, BMI, LH levels at stimulation outset, LH levels on day of antagonist administration, and total number of stimulation days. Importantly, when analyzing the data of specific age groups, the model's prediction was strongest in young patients (age 25-30 years, R2 = 0.88, p < .001) and weakest in older patients (age > 41 years, R2 = 0.23, p = .003). Conclusions: Using both multiple linear regression and a machine-learning-based algorithm of patient data from IVF cycles, we were able to predict patients at risk for premature LH rise and/or LH surge. Utilizing this model may help prevent IVF cycle cancellation and better timing of ovulation triggering.

The generation of sulfate species on Ir-based catalysts for boosting NO reduction with CO under the coexistence of O2 and SO2 atmosphere.

Generally, sulfur poisoning is considered to be one of the main factors contributing to the deactivation of selective catalytic reduction of NOx by CO (CO-SCR) catalysts, while the promotional effect of SO2 on NO reduction over Ir/SiO2 is observed which is an interesting scientific phenomenon. After the introduction of 20 ppm SO2, NOx conversion increased from âˆ¼ 40 % to âˆ¼ 90 % at 275 °C, and N2 selectivity increased from âˆ¼ 80 % to 100 % at 200 âˆ¼ 300 °C. Furthermore, the promoting effect could remain unchanged after 24 h of continuous reaction. However, the temperature point for achieving complete conversion of CO increased from 225 °C to 275 °C after the introduction of SO2. Experimental characterization and theoretical calculation jointly proved that the inhibition of CO oxidation by the generation of sulfate was the main reason for promoting NO reduction. Under the coexistence of O2 and SO2, SO2 was firstly oxidized to SO3 on the iridium surface and generated sulfate species on surface hydroxyl groups of SiO2. Some active sites for O2 adsorption were covered by the generated surface sulfate, and adsorbed CO was hard to react with adsorbed O2, resulting in Langmuir-Hinshelwood (L-H) reaction pathways for CO oxidation being inhibited. Therefore, unoxidized CO reacted with NO adsorbed species and generated N2O to generate N2 and CO2, improving NO reduction. This new insight has implications for understanding the promotional effect of SO2 on NO reduction with CO in the presence of O2.

Targeted inhibition of kisspeptin neurons reverses hyperandrogenemia and abnormal hyperactive LH secretion in a preclinical mouse model of polycystic ovary syndrome.

STUDY QUESTION: Do hyperactive kisspeptin neurons contribute to abnormally high LH secretion and downstream hyperandrogenemia in polycystic ovary syndrome (PCOS)-like conditions and can inhibition of kisspeptin neurons rescue such endocrine impairments? SUMMARY ANSWER: Targeted inhibition of endogenous kisspeptin neuron activity in a mouse model of PCOS reduced the abnormally hyperactive LH pulse secretion and hyperandrogenemia to healthy control levels. WHAT IS KNOWN ALREADY: PCOS is a reproductive disorder characterized by hyperandrogenemia, anovulation, and/or polycystic ovaries, along with a hallmark feature of abnormal LH hyper-pulsatility, but the mechanisms underlying the endocrine impairments remain unclear. A chronic letrozole (LET; aromatase inhibitor) mouse model recapitulates PCOS phenotypes, including polycystic ovaries, anovulation, high testosterone, and hyperactive LH pulses. LET PCOS-like females also have increased hypothalamic kisspeptin neuronal activation which may drive their hyperactive LH secretion and hyperandrogenemia, but this has not been tested. STUDY DESIGN, SIZE, DURATION: Transgenic KissCRE+/hM4Di female mice or littermates Cre- controls were treated with placebo, or chronic LET (50 µg/day) to induce a PCOS-like phenotype, followed by acute (once) or chronic (2 weeks) clozapine-N-oxide (CNO) exposure to chemogenetically inhibit kisspeptin cells (n = 6 to 10 mice/group). PARTICIPANTS/MATERIALS, SETTING, METHODS: Key endocrine measures, including in vivo LH pulse secretion patterns and circulating testosterone levels, were assessed before and after selective kisspeptin neuron inhibition and compared between PCOS groups and healthy controls. Alterations in body weights were measured and pituitary and ovarian gene expression was determined by qRT-PCR. MAIN RESULTS AND THE ROLE OF CHANCE: Acute targeted inhibition of kisspeptin neurons in PCOS mice successfully lowered the abnormally hyperactive LH pulse secretion (P < 0.05). Likewise, chronic selective suppression of kisspeptin neuron activity reversed the previously high LH and testosterone levels (P < 0.05) down to healthy control levels and rescued reproductive gene expression (P < 0. 05). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Ovarian morphology was not assessed in this study. Additionally, mouse models can offer mechanistic insights into neuroendocrine processes in PCOS-like conditions but may not perfectly mirror PCOS in women. WIDER IMPLICATIONS OF THE FINDINGS: These data support the hypothesis that overactive kisspeptin neurons can drive neuroendocrine PCOS-like impairments, and this may occur in PCOS women. Our findings complement recent clinical investigations using NKB receptor antagonists to lower LH in PCOS women and suggest that pharmacological dose-dependent modulation of kisspeptin neuron activity may be a valuable future therapeutic target to clinically treat hyperandrogenism and lower elevated LH in PCOS women. STUDY FUNDING/COMPETING INTEREST(S): This research was supported by NIH grants R01 HD111650, R01 HD090161, R01 HD100580, P50 HD012303, R01 AG078185, and NIH R24 HD102061, and a pilot project award from the British Society for Neuroendocrinology. There are no competing interests.

Characterization of the somatostatin system in tilapia: implications for growth and reproduction.

Somatostatin (SST) plays diverse physiological roles in vertebrates, particularly in regulating growth hormone secretion from the pituitary. While the function of SST as a neuromodulator has been studied extensively, its role in fish and mammalian reproduction remains poorly understood. To address this gap, we investigated the involvement of the somatostatin system in the regulation of growth and reproductive hormones in tilapia. RNA sequencing of mature tilapia brain tissue revealed the presence of three SST peptides: SST6, SST3, and low levels of SST1. Four different isoforms of the somatostatin receptor (SSTR) subfamily were also identified in the tilapia genome. Phylogenetic and synteny analysis identified tiSSTR2-like as the root of the tree, forming two mega clades, with SSTR1 and SSTR4 in one and SSTR2a, SSTR3a, and SSTR5b in the other. Interestingly, the tiSSTR-5 isoforms 5x1, 5x2, and 5x3 were encoded in the sstr3b gene and were an artifact of misperception in the nomenclature in the database. RNA-seq of separated pituitary cell populations showed that SSTRs were expressed in gonadotrophs, with sstr3a enriched in luteinizing hormone (LH) cells and sstr3b significantly enriched in follicle-stimulating hormone (FSH) cells. Notably, cyclosomatostatin, an SSTR antagonist, induced cAMP activity in all SSTRs, with SSTR3a displaying the highest response, whereas octreotide, an SSTR agonist, showed a binding profile like that observed in human receptors. Binding site analysis of tiSSTRs from tilapia pituitary cells revealed the presence of canonical binding sites characteristic of peptide-binding class A G-protein-coupled receptors. Based on these findings, we explored the effect of somatostatin on gonadotropin release from the pituitary in vivo. Whereas cyclosomatostatin increased LH and FSH plasma levels at 2 h post-injection, octreotide decreased FSH levels after 2 h, but the LH levels remained unaffected. Overall, our findings provide important insights into the somatostatin system and its mechanisms of action, indicating a potential role in regulating growth and reproductive hormones. Further studies of the complex interplay between SST, its receptors, and reproductive hormones may advance reproductive control and management in cultured populations.

Male Body Odor Affects Emotional State, LH, and Cortisol Secretion in Women of Different Age Groups.

Hormone changes across women's menstrual cycles may lead to changes in their perceptions of chemical signals and their hormonal responses to these cues. The aim of the present study was to determine the role of menstrual cycle phase in the response to extracts of male axillary secretions (EMAS) in women. We tested healthy reproductive age and premenopausal women (n = 29). An EMAS/control solution was applied once every two hours during either the follicular or luteal phase, at which point saliva samples for luteinizing hormone (LH) and cortisol monitoring were collected. LH and cortisol concentrations were analyzed using the enzyme immunoassay (EIA) technique. Positive and Negative Affect Schedule (PANAS) and Visual Analogue Scales (VAS) scores were used to assess the participants' moods. For the first time, we showed that EMAS may produce opposite effects on LH secretion depending on the menstrual cycle phase of the recipient. We observed a significant increase in the number of LH peaks (p = 0.0447) and their amplitudes (p = 0.0469) when EMAS was applied during the follicular phase, while the same application in the luteal phase lowered the amplitudes of LH peaks (p = 0.0382). For the first time, we showed that EMAS application increased salivary cortisol levels in reproductive age women relative to premenopausal women (p = 0.0032). PANAS scores revealed changes in positive and negative affect after EMAS application. Our data indicate the significance of the menstrual cycle phase for EMAS' effects on LH secretion and mood, but not on cortisol secretion in women.

Intracerebroventricular injection of spexin stimulates the hypothalamic-pituitary-testicular axis and increases the secretion of male reproductive hormones in rats.

BACKGROUND: Male reproductive functions are regulated in the hypothalamic-pituitary-gonadal (HPG) axis. Any problem in this axis would lead to the deterioration of reproductive functions. The present study aimed to investigate the effects of intracerebroventricular (icv) Spexin (SPX) infusion on the HPG axis in detail. METHODS: 40 Wistar albino rats were divided into four groups: control, sham, SPX 30 nmol and SPX 100 nmol (n=10). 30 nmol/1 µl/hour SPX was administered icv to the rats in the SPX 30 nmol group for 7 days, while rats in the SPX 100 nmol group were administered 100 nmol/1 µl/hour SPX. On the 7th day, the rats were decapitated, blood and tissue samples were collected. Serum LH, FSH and testosterone levels were determined with the ELISA method, GnRH mRNA expression level was determined in hypothalamus with the RT-PCR method. Seminiferous tubule diameter and epithelial thickness were determined with the hematoxylin-eosin staining method. RESULTS: SPX infusion was increased GnRH mRNA expression in the hypothalamus tissue independent of the dose (p<0.05). Serum LH, FSH and testosterone levels in the SPX groups were increased when compared to the control and sham groups independent of the dose (p <0.05). Histological analysis revealed that SPX infusion did not lead to any changes in seminiferous epithelial thickness, while the tubule diameter increased in the SPX groups (p<0.05). CONCLUSION: The study findings demonstrated that icv SPX infusion stimulated the HPG axis and increased the secretion of male reproductive hormones.

Gonadotropin Activity during Early Folliculogenesis and Implications for Polycystic Ovarian Syndrome and Premature Ovarian Insufficiency: A Narrative Review.

Female fertility depends on the ovarian reserve of follicles, which is determined at birth. Primordial follicle development and oocyte maturation are regulated by multiple factors and pathways and classified into gonadotropin-independent and gonadotropin-dependent phases, according to the response to gonadotropins. Folliculogenesis has always been considered to be gonadotropin-dependent only from the antral stage, but evidence from the literature highlights the role of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) during early folliculogenesis with a potential role in the progression of the pool of primordial follicles. Hormonal and molecular pathway alterations during the very earliest stages of folliculogenesis may be the root cause of anovulation in polycystic ovary syndrome (PCOS) and in PCOS-like phenotypes related to antiepileptic treatment. Excessive induction of primordial follicle activation can also lead to premature ovarian insufficiency (POI), a condition characterized by menopause in women before 40 years of age. Future treatments aiming to suppress initial recruitment or prevent the growth of resting follicles could help in prolonging female fertility, especially in women with PCOS or POI. This review will briefly introduce the impact of gonadotropins on early folliculogenesis. We will discuss the influence of LH on ovarian reserve and its potential role in PCOS and POI infertility.

Early-Life Resource Scarcity in Mice Does Not Alter Adult Corticosterone or Preovulatory Luteinizing Hormone Surge Responses to Acute Psychosocial Stress.

Early-life stressors can affect reproductive development and change responses to adult stress. We tested if resource scarcity in the form of limited bedding and nesting (LBN) from postnatal days (PND) 4 to 11 delayed sexual maturation in male and female mice and/or altered the response to an acute, layered, psychosocial stress (ALPS) in adulthood. Contrary to the hypotheses, age and mass at puberty were unaffected by the present application of LBN. Under basal conditions and after ALPS, corticosterone concentrations in males, diestrous females, and proestrous females reared in standard (STD) or LBN environments were similar. ALPS disrupts the luteinizing hormone (LH) surge in most mice when applied on the morning of proestrus; this effect was not changed by resource scarcity. In this study, the paucity of effects in the offspring may relate to a milder response of CBA dams to the paradigm. While LBN dams exited the nest more often and their offspring were smaller than STD-reared offspring on PND11, dam corticosterone concentrations were similar on PND11. To test if ALPS disrupts the LH surge by blunting the increase in excitatory GABAergic input to gonadotropin-releasing hormone (GnRH) neurons on the afternoon of proestrus, we conducted whole-cell voltage-clamp recordings. The frequency of GABAergic postsynaptic currents in GnRH neurons was not altered by LBN, ALPS, or their interaction. It remains possible that ALPS acts at afferents of GnRH neurons, changes response of GnRH neurons to input, and/or alters pituitary responsiveness to GnRH and that a more pronounced resource scarcity would affect the parameters studied.