Physiological and Pharmacological overview of the Gonadotropin Releasing Hormone

Restorative mechanisms of Shugan Yiyang capsule on male infertility through 'pharmaco-metabo-net' tripartite correlation analysis

BACKGROUND

Shugan Yiyang capsule (SGYY), a commonly used traditional Chinese medicine formulation, is primarily indicated for the treatment of erectile dysfunction, yet existing studies on the therapeutic effects on male infertility (MI) are insufficient and the specific mechanisms remain poorly understood. Given the close relationship between MI, sperm quality, and erectile function, this study aims to investigate the role of SGYY in the restoration of MI and explore the underlying mechanisms.

METHODS

The efficacy of SGYY is comprehensively evaluated through pharmacodynamic, metabolomic, and network pharmacology. Sperm parameters, reproductive hormones, sexual behavior, neural enzymes, oxidative stress markers, pro-inflammatory cytokines, and testicular histopathology are measured to reveal the restorative effects of MI. Furthermore, urine and serum metabolomics, along with network pharmacology and surface plasmon resonance, are employed to explore the molecular mechanisms and predict core targets.

RESULTS

SGYY significantly improved overall health parameters, including body weight, water intake, urine output, food consumption, and spontaneous activity. Specifically, SGYY prominently recovered sexual behavior, ameliorated sperm quality, increased mitochondrial membrane potential, normalized reproductive hormones, upregulated endothelial nitric oxide synthase, attenuated oxidative stress markers, and pro-inflammatory cytokines, and repaired testicular pathological damage. Metabolomic analysis identified 47 candidate biomarkers, among which SGYY significantly modulated 39 potential biomarkers, encompassing 8 main metabolic pathways such as histidine metabolism, cysteine and methionine metabolism, propanoate metabolism, and taurine and hypotaurine metabolism. Additionally, network pharmacology predicted 8 core targets, comprising HSP90AA1, ESR1, MAPK1, CASP3, IL6, TNF, BCL2, and MAPK8.

CONCLUSION

SGYY improves sperm quality and erectile function by regulating oxidative stress, energy metabolism, and neurological function, thereby exerting a restorative effect on MI, as evidenced by the modulation of 8 main metabolic pathways, 39 potential biomarkers, and 8 core targets. Pharmacodynamic provides foundational validation, metabolomic uncovers intrinsic metabolic changes, and network pharmacology predicts therapeutic targets, with findings from the 'Pharmaco-Metabo-Net' tripartite correlation analysis providing a solid theoretical strategy and scientific evidence to support the clinical application of SGYY in restoring MI.

Influences of non-nutritive sweeteners on sweet taste receptors and reproductive hormone signaling in guinea pigs

Non-nutritive sweeteners (NNS) are widespread in the food industry, but their effects on reproductive endocrine function remain inadequately characterized within the current scientific literature. This study investigated NNS impacts on hypothalamic-pituitary-ovarian (HPO) axis function in guinea pigs. The results showed that the NNS groups exhibited significantly lower serum levels of gonadotropin-releasing hormone (GnRH) and follicle-stimulating hormone (FSH) compared to controls, with rebaudioside A (RA) showing the lowest GnRH. Conversely, luteinizing hormone (LH) concentrations were significantly elevated in NNS groups. The RA group exhibited increased testosterone (T) levels, and all experimental groups showed more SS follicular cysts. T1R2 protein expression was highest in the sucralose (TGS) group, while gonadotropin-releasing hormone receptor (GnRHR) expression decreased significantly in NNS groups, particularly with RA. Luteinizing hormone receptor (LHR) protein expression increased significantly in NNS groups, with no changes in follicle-stimulating hormone receptor (FSHR) or T1R3 expression. Therefore, NNS supplementation affects HPO axis function in guinea pigs, as evidenced by decreased serum GnRH and FSH levels, increased LH content, inhibited GnRHR protein expression, and promoted LHR protein expression. The observed upregulation of T1R2 protein expression in the TGS group suggests a potential link between sweet taste receptor activation and reproductive hormone regulation.

Weighing up GnRH agonist therapy for endometriosis: outcomes and the treatment paradigm

INTRODUCTION

Endometriosis is a chronic inflammatory estrogen-dependent disease affecting 10% of women worldwide leading to chronic pelvic pain and infertility which may be treated clinically or surgically.

AREAS COVERED

Current literature was reviewed using the keywords 'gonadotropin releasing hormone agonists (GnRHa),' 'endometriosis,' 'infertility' and 'chronic pelvic pain.' Relevant papers prioritizing randomized controlled clinical trials (RCT), systematic reviews, meta-analyses, as well as international guidelines were evaluated.

EXPERT OPINION

Available options for relieving endometriosis-associated pain include GnRHa, progestagens, and combined oral contraceptives, all of which block menstruation to control symptoms without curing the disease. GnRHa administration decreases pain and symptom recurrence after surgical treatment, but side effects and costs limit its use. Published studies to test its effectiveness in easing endometriosis-associated pain are heterogeneous, consider different outcomes with no long-term results. Drug choice should be individualized considering the side-effect profile, tolerability, costs, risks, and benefits as one size does not fit all. As we wait for the development of an ideal pharmacological agents, GnRHa with an add-back regimen remains a second-line option to alleviate the painful symptoms in women with endometriosis. Endometriosis management should consider the systemic nature of the disease and the complexity involved in the pathogenesis of symptoms.

Is There a Role for Hormonal Therapy in Men with Oligoasthenoteratozoospermia (OAT)?

Hormonal factors play an essential role as an underlying causative factor of oligoasthenoteratozoospermia (OAT), and these patients can benefit from hormonal medications that modulate the hypothalamic-pituitary-gonadal axis. This review aims to outline the various medications used as hormonal therapy in treating infertile men with OAT. This manuscript focuses on essential hormonal evaluation, identifying men who would benefit from treatment, selecting the appropriate medication, determining the duration of therapy, and evaluating hormonal treatment outcomes. Additionally, novel markers that can broaden the horizon of hormonal treatment in infertile men with OAT are discussed. Hormonal-based therapy options in men with OAT include selective estrogen receptor modulators (SERMs), aromatase inhibitors (AIs), dopamine agonists, and injections such as gonadotropin-releasing hormone (GnRH) analogs and gonadotropins. Treatment duration and the expected success will dictate the final treatment type for couples. In conclusion, hormonal therapy may improve spermatogenesis in infertile men with low serum testosterone. Gonadotropins and SERMs may increase sperm parameters in men with infertility and normal serum gonadotropin levels. AIs might help improve spermatogenesis in infertile men with a total testosterone (ng/mL)/estradiol (pg/mL) ratio < 0.10. In addition, dopamine agonists may play a role in enhancing spermatogenesis in infertile men with hyperprolactinemia.

GnRH Peptide Antagonist: Comparative Analysis of Chemistry and Formulation with Implications for Clinical Safety and Efficacy

Overexpression of the gonadotropin-releasing hormone receptor (GnRH-R) plays a vital role in the advancement of reproductive malignancies such as ovarian, endometrial, and prostate cancer. Peptidomimetic GnRH antagonists are a substantial therapeutic development, providing fast and reversible suppression of gonadotropins by directly blocking GnRH-R. Unlike typical GnRH agonists, these antagonists prevent the early hormonal flare, have a faster onset of action, and have a lower risk of cardiovascular problems. These characteristics qualify GnRH antagonists as revolutionary therapy for diseases such as advanced prostate cancer, endometriosis, uterine fibroids, and in vitro fertilization procedures. Key GnRH peptide antagonists authorized by the regulatory agencies include Cetrorelix, Ganirelix, Abarelix, Degarelix, and Teverelix. Assisted reproductive technologies (ART) are dominated by Cetrorelix and Ganirelix, while Degarelix and Abarelix have shown significant promise in treating advanced prostate cancer. Teverelix appears as a next-generation GnRH antagonist with an ideal mix of efficacy and safety, showing promise in a variety of reproductive and hormone-dependent illnesses. This review investigates the pharmacological role of GnRH in reproductive physiology and its consequences in disease, emphasizing structural advances in third- and fourth-generation GnRH antagonists. All GnRH peptide-based antagonists were analyzed in detail for formulation strategy, pharmacokinetics, effectiveness, and safety. This review also emphasizes GnRH antagonists' clinical promise, providing insights into their evolution and the possibility for future research in developing safer, more effective treatments for complicated hormonal diseases.

Novel non-peptide uracil-derived human gonadotropin-releasing hormone receptor antagonists

Gonadotropin-releasing hormone (GnRH) is the main regulator of the reproductive system, acting on gonadotropic cells by binding to the GnRH1 receptor (GnRH1R). Traditionally, therapies targeting this receptor have relied on peptide modulators, which required subcutaneous or intramuscular injections. Due to the limitations of the parenteral administrations, there is a growing interest in developing oral small molecule modulators of GnRH1R as more convenient therapeutic alternatives. In this study, we examined the potential of chemically modifying elagolix, the first approved non-peptide, orally active GnRH1R antagonist, to increase its atropisomeric properties by introducing new moieties. We designed and synthesized the thio-uracil (1) and cytosine (2) derivatives of elagolix, both demonstrating GnRH1R antagonistic activities, with EC50 values of 39 and 110 nM, respectively. The atropisomers of 1 and 2 were efficiently separated using silica gel chromatography, and extensive NMR investigation, supported by Density Functional Theory (DFT) calculations, allowed us to define their conformations and rotational barriers. Docking and Molecular Dynamics (MD) studies revealed that 1 and 2 bind to GnRH1R with ΔG values comparable to elagolix, but through distinct binding modes. These results highlight the potential of non-peptide modulators to effectively modulate GnRH1R activity and pave the way for developing novel modulators.

Gonadal Development and Differentiation of Hybrid F1 Line of Ctenopharyngodon idella (♀) × Squaliobarbus curriculus (♂)

The hybrid F1 offspring of Ctenopharyngodon idella (♂) and Squaliobarbus curriculus (♀) exhibit heterosis in disease resistance and also show abnormal sex differentiation. To understand the mechanism behind gonadal differentiation in the hybrid F1, we analyzed the transcriptomes of C. idella, S. curriculus, and the hybrid F1; screened for genes related to gonad development in these samples; and measured their expression levels. Our results revealed that compared to either C. idella or S. curriculus, the gene expressions in most sub-pathways of the SNARE interactions in the vesicular transport pathway in the hypothalamus, pituitary, and gonadal tissues of their hybrid F1 offspring were significantly up-regulated. Furthermore, insufficient transcription of genes involved in oocyte meiosis may be the main reason for the insufficient reproductive ability of the hybrid F1 offspring. Through transcriptome screening, we identified key molecules involved in gonad development, including HSD3B7, HSD17B1, HSD17B3, HSD20B2, CYP17A2, CYP1B1, CYP2AA12, UGT2A1, UGT1A1, and FSHR, which showed significant differences in expression levels in the hypothalamus, pituitary, and gonads of these fish. Notably, the expression levels of UGT1A1 in the gonads of the hybrid F1 were significantly higher than those in C. idella and S. curriculus. These results provide a scientific basis for further research on the gonadal differentiation mechanism of hybrid F1 offspring.

Neuroendocrine modulation by metamizole and indomethacin: investigating the impact on neuronal markers and GnRH release

PURPOSE

Some evidence that non-steroidal anti-inflammatory drugs have neuroprotective effects indicates their potential for use in a new field. However, their effects on hormone secretion have yet to be adequately discovered. Therefore, we aimed to evaluate the effects of metamizole and indomethacin on neuronal markers as well as the GnRH expression in the GT1-7 cell line.

METHODS

The effects of these drugs on proliferation were evaluated by MTT analysis. The effect of 10-50-250 µM concentrations of the drugs also on the expression of neuronal factors and markers, including NGF, nestin and βIII Tubulin, and additionally GnRH, was determined by the RT-qPCR method.

RESULTS

NGF and nestin mRNA expressions were increased in all concentrations of both metamizole and indomethacin. No changes were detected in βIII Tubulin. While metamizole showed an increase in GnRH mRNA expression, there was no change at 10 and 50 µM concentrations of indomethacin, but a remarkable decrease was observed at 250 µM concentrations.

CONCLUSIONS

The results of our study showing an increase in the expression of neuronal factors reveal that metamizole and indomethacin may have possible neuroprotective effects. Moreover, the effects on the GnRH expression appear to be different. Animal models are required to confirm these effects of NSAIDs on neurons.

A disproportionality analysis of adverse events caused by GnRHas from the FAERS and JADER databases

Background

Gonadotrophin-releasing hormone analogs (GnRHas) play a significant role in addressing gynecological diseases, central precocious puberty, and cancer. However, ensuring the safety of GnRHas in real-world applications requires continuous vigilance. In light of this, we undertook a disproportionality analysis focused on adverse events (AEs) associated with GnRHas using data from both the FDA Adverse Event Reporting System (FAERS) and the Japanese Adverse Drug Event Report (JADER). We evaluated GnRHas-associated AEs and characterized the clinical priority of unlisted AEs caused by each GnRHa from the different databases.

Methods

In the disproportionality analysis, we applied two adjusted algorithms to identify signals related to GnRHas in the FAERS and JADER databases from 2004 to 2023. Additionally, we utilized the Statistical Analysis System (SAS, 9.4) to examine potential and high-aROR (adjusted reporting odds ratio) signals associated with GnRHas. We performed clinical priority assessment for suspicious PTs and an analysis of serious/non-serious outcomes. We also gathered information on the onset times of AEs linked with GnRHas from both databases.

Results

From January 2004 to September 2023, FAERS and JADER recorded a total of 50,360,413 and 1,440,200 AEs, respectively. Employing two algorithms, the suspicious preferred terms (PTs) related to leuprolide (Leu) were 562 potential PTs (44 unlisted in specifications), followed by goserelin (Gos) with 189 PTs (28 unlisted), triptorelin (Tri) with 172 PTs (28 unlisted), and Leu-JADER with 85 PTs (10 unlisted). At the same PT level, the differences in GnRHas between the two databases were observed, such as cardiac failure, diabetes mellitus, liver disorder, dementia, suicidal ideation, interstitial lung disease, urinary disorders, and hypertensive crisis. In an analysis of serious vs. non-serious outcomes, a total of 43 AEs of Leu were more likely to be reported as serious AEs with p < 0.05 (such as asthenia, urinary retention, diabetes mellitus, interstitial lung disease, gait disturbance, and so on), following by Tri (6 AEs), and Gos (4 AEs). Based on the clinical priority score, 41 PTs of Leu, 26 PTs of Tri, 24 PTs of Gos, and 8 PTs of Leu-JADER were graded as weak. There were 3 PTs of Leu, 2 PTs of Tri, 4 PTs of Gos, and 2 PTs of Leu-JADER that were graded as moderate. Notably, in the assessment of the relevant evidence, 2 PTs (loss of libido and urinary tract toxicity caused by Leu), 1 PT (electrolyte imbalance caused by Tri), and 2 PTs (anorexia and suicidal ideation caused by Gos) showed a strong level of evidence with "++." The differences in the signal strength of the same PTs from two databases were also worth noting. Moreover, the median onset time for GnRHas (Leu, Tri, and Gos) was 23 days (0, 298), 22 days (0, 181), and 217 days (29, 706), respectively, as median (Q1, Q3).

Conclusion

An examination of two databases revealed suspicious AEs associated with GnRHas. Our study found potential new AE signals of GnRHas and supported continuous clinical monitoring, pharmacovigilance, regional differences, and further studies of GnRHas.

Neuromodulators and neuroepigenetics of social behavior in ants

Eusocial insects exemplify a remarkable system of division of labor within the same colony. This behavioral range, which is sometimes accompanied by morphological or physiological differences, provides an opportunity to study the relationship between complex behaviors and their underlying molecular mechanisms. This is especially true in ants because certain genera have an elaborate caste system and can dramatically change their stereotypical behavior over their lifetime. Recent studies experimentally alter ant behavior over short times, thus opening the study of underlying plasticity pathways. The molecular underpinnings of these behaviors are neuromodulators as well as the regulation of chromatin. Here, we concisely review the current understanding of the relationship between neuromodulators, epigenetics, and social behavior in ants. We discuss future directions in light of experimental limitations of the ant system.