Hypothalamic-pituitary-gonadal Axis Research Articles

Effects of mifepristone, a model compound with anti-progestogenic activity, on the reproduction of African clawed frog (Xenopus laevis)

This is the first study on how a substance with anti-progestogenic activity affects amphibian reproduction. Mifepristone, a synthetic anti-progestin used in abortion pills, was chosen as model compound. African clawed frog (Xenopus laevis) females were exposed to four mifepristone concentrations (0.7, 9, 120, and 1380ng∙L−1) for 30 days. A control group was also included. Egg-laying during the experiment was significantly less at the highest concentration. At the experiment’s end, mifepristone-exposed and control females were randomly mated with sexually mature males. Breeding rate for females exposed to 1380ng∙L−1 mifepristone was only 50%. Histology revealed no significant changes in gonads, thyroid, or liver. Females exposed to 1380ng∙L−1 mifepristone had lower estradiol levels in plasma, lower mRNA expression of lh and fsh in brain–pituitary complex, and p450scc in ovaries. In liver, mRNA level of npr was significantly increased in females exposed to 120ng∙L−1 mifepristone. mRNA expression of mpr, erβ, dio2, and dio3 were upregulated in animals exposed to 9ng∙L−1 and 120ng∙L−1 mifepristone, whereas vtg expression was significantly downregulated in females exposed to 1380ng∙L−1 mifepristone. All these findings show that exposure to compounds with anti-progestogenic activity affects the hypothalamus–pituitary–gonad axis and decreases reproductive success.

Toxic effects of chronic exposure to BPAF and perturbation of gut microbiota homeostasis in marine medaka (Oryzias melastigma)

Bisphenol AF (BPAF), a substitute for bisphenol A (BPA), exhibits potent endocrine-disrupting properties that pose a serious health hazard to organisms. This study employed marine medaka as a model, subjecting them to different concentrations of BPAF (0.61, 6.65, and 91.88 μg/L) from the embryonic stage for a period of 160 days. Findings showed that 91.88 μg/L BPAF reduced survival rates and altered sex ratios. Furthermore, exposure to BPAF at all concentrations led to a significant increase in body length and weight. Behavioral analysis revealed that BPAF exposure impaired the swimming ability of the medaka. Histological changes included disrupted ovarian development, reduced sperm count, liver inflammation, and intestinal damage. Gene expression analysis revealed impacts on nervous system (e.g., gap43, itr, elavl3), HPG axis (e.g., gthα, erα, 3βhsd), and liver genes (e.g., chgl, vtg2). Additionally, BPAF altered the diversity and richness of gut microbes in marine medaka, leading to significant changes in specific bacterial species and intestinal functions. In conclusion, long-term BPAF exposure induced neurotoxicity, reproductive toxicity, and impaired digestive and immune systems in marine medaka, with sex-specific effects. These results provide further evidence of the potential hazards of BPAF as an environmental pollutant.

Association between Metal(loid) Exposure and Risk of Polycystic Ovary Syndrome Mediated by Anti-Müllerian Hormone among Women Undergoing In Vitro Fertilization and Embryo Transfer

ObjectiveTo investigate the relationship and potential pathways between metal(loid) exposure and the risk of polycystic ovary syndrome (PCOS) in women of childbearing age. MethodsThis case-control study included 200 patients with PCOS (cases) and 896 non-PCOS controls with the age of 25–37 years. The concentrations of 29 metal(loid)s in the follicular fluid (FF) and clinical indicators in the serum were measured in all participants. Logistic regression analysis and mediation analysis were conducted to evaluate the associations between metal(loid) exposure and PCOS risk and investigate the possible roles of clinical indicators, respectively. ResultsLogistic regression analysis revealed an association between high copper levels in FF and increased PCOS risk (highest vs. lowest quartile: adjusted odds ratio = 2.94, 95% confidence interval: 1.83–4.72). A high luteinizing hormone/follicle-stimulating hormone ratio and elevated levels of testosterone and anti-Müllerian hormone (AMH) were strongly associated with increased PCOS risk induced by high copper exposure. The mediation analysis indicated a mediating effect of AMH in the association between copper exposure and PCOS risk. ConclusionCopper may affect PCOS risk through the hypothalamic–pituitary–ovarian axis, mediated by AMH. Copper exposure and internal AMH levels are important indicators for early warning of PCOS development.

The antidepressant-like effects of kisspeptin-10 are reversed by kisspeptin antagonist peptide 234 in male rats.

Kisspeptins are reported to be the most potent activators of the hypothalamus-pituitary-gonadal (HPG) axis known to date. Kisspeptin potently elicits gonadotropin-releasing hormone (GnRH) release and luteinizing hormone (LH) secretion, even in the pre-pubertal period. Beyond the hypothalamus, kisspeptin is also expressed in limbic and paralimbic brain regions, which are areas of the neurobiological network primarily implicated in emotional behaviors alongside sexual functions. Therefore, an increasing body of studies has implicated kisspeptin as having many influences on emotional behaviors. The study was set out to explore if the kisspeptin/GPR54 signaling system is required for the anti-depressant-like effect of kisspeptin-10 (KP-10), besides the regulation of the HPG axis. To test this concept, peptide 234 (P234), a kisspeptin antagonist, was given to the male rats, and its modulatory effect on the anti-depressant-like effects of kisspeptin was investigated by using a forced swimming test (FST). The study has also sought to know whether kisspeptin can exert its effects through adrenergic and serotonergic receptors. To investigate this, the agents yohimbine (Yoh), an alpha-2 adrenergic receptor antagonist, and cyproheptadine (Cry), a non-selective 5-HT2 serotonergic receptor antagonist, were administered in the experiments. Our results indicate that, in rats, the anti-depressant-like effects of KP-10 in a modified rat FST are mediated by GPR54 receptors, since the kisspeptin antagonist peptide 234 reversed kisspeptin-induced anti-depressant-like effects. Our data also demonstrate that the anti-depressant-like effects of kisspeptin, at least in part, are mediated by an interaction of the alpha-2 adrenergic and 5-HT2 serotonergic receptors.

Expression profile of RFRP-3 gene in hypothalamic tissue and its relationship with reproductive hormones across phases of the estrous cycle in female rats

The expression profile of RFRP-3 during the different phases of the estrous cycle and its relationship with reproductive hormones were studied in 36 adult female Wister rats. Phases of the estrous cycle were characterized by visual observation of the vagina and vaginal exfoliated cell cytology. The expression profile of the RFRP-3 gene in the hypothalamic tissue was evaluated by real-time qPCR. Reproductive hormones (LH, FSH, estrogen, and progesterone) were measured from plasma by enzyme immunoassay. The expression level of RFRP-3 was significantly higher (P < 0.01) during diestrus compared to other phases of the estrous cycle. The lowest expression level was detected during estrus and metestrus. The highest level of LH was detected during the proestrus and metestrus and the lowest during the diestrus. Higher expression of RFRP 3 during diestrus is consistent with the higher level of estrogen, however, the lower expression of RFRP 3 during estrus and met estrus did not corroborate with the level of estrogen. The findings of this research work revealed significant up-regulation of RFRP-3 during the estrous cycle together with higher estrogen level. Therefore it can be concluded that higher expression of RFRP 3 may lead to the suppression of the HPG axis during diestrus in rats and estrogen may be involved in the regulation of RFRP-3.

Precocious Puberty in Boys with NR0B1 Variants

Precocious puberty (PP) requires appropriate management to prevent short adult height, psychosocial issues, and other adverse outcomes. Genetic diagnosis potentially improves the management of PP. Pathogenic NR0B1 variants, which typically cause X-linked adrenal hypoplasia congenita, can also affect gonadal function. While boys with NR0B1 variants usually exhibit hypogonadotropic hypogonadism during adolescence, previous reports have suggested that minipuberty, a physiological transient activation of the hypothalamic–pituitary–gonadal axis during infancy, occurs in these patients and can persist beyond a typical duration. In rare cases, NR0B1 variants cause PP. PP associated with NR0B1 variants has unique features such as early onset and high serum testosterone levels that are often disproportionate to testicular size. Three underlying mechanisms have been proposed for the association between PP and NR0B1 variants: (1) adrenocorticotropic hormone (ACTH)-dependent, (2) gonadotropin-dependent, and (3) ACTH- and gonadotropin-independent mechanisms. The factors contributing to PP vary among cases. Determining the underlying mechanisms is crucial for adopting appropriate therapeutic strategies to control PP. However, as the detailed molecular networks mediating these mechanisms are largely unclear, further research is needed to pave the way for a more effective and personalized management of patients with PP associated with NR0B1 variants.

Disorders of puberty

Puberty is a critical developmental phase marking the transition from childhood to adulthood, characterised by physical, hormonal and psychological changes. Disorders of puberty can have a significant impact on a person’s growth, development, and psychological well-being. These disorders can cause precocious (early onset) or delayed (late onset) puberty and necessitate a thorough understanding of the underlying mechanisms and clinical presentation to ensure proper diagnosis and treatment. This article provides a comprehensive overview of the hypothalamic–pituitary–gonadal axis and adrenal development leading to physical changes consistent with puberty. This article outlines the physiological physical changes and pubertal milestones and discusses normal variants of puberty to help distinguish physiological from pathological conditions. It then describes the pathophysiology and causes for both precocious and delayed pubertal development, providing guidance for primary care physicians for referral to secondary care. Finally, this article aims to provide succinct guidance on relevant history and clinical findings pertinent to the topic and provides a clinical case for discussion.

Comprehensive analysis of mRNA and miRNA differential expression profiles in the hypothalamus-pituitary-gonadal axis in laying and broodiness period of Wanxi white geese

The hypothalamus-pituitary-gonadal (HPG) axis is an important neuroendocrine regulatory center involved in egg-laying process in poultry. However, its mechanism of regulating broodiness behavior and laying performance in geese remains unclear. This study explored the molecular mechanism by which the HPG axis regulates brooding behavior in Wanxi white geese (WWG). The hypothalamus, pituitary, and ovarian tissues of Wanxi white geese were collected at laying and brooding periods for transcriptome sequencing analysis. A total of 240 (BH vs. LH), 319 (BP vs. LP), and 445 (BO vs. LO) differentially expressed genes, and 56 (BH vs. LH), 82 (BP vs. LP), and 48 (BO vs. LO) differentially expressed miRNAs were identified. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis showed that differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) were significantly enriched in hormone level regulation, cell communication, calcium signaling pathway, GnRH signaling pathway, MAPK signaling pathway, Wnt signaling pathway, and other processes. Six DEGs and four DEMs were randomly selected for real-time fluorescence quantitative reverse transcription PCR (RT-qPCR). The results showed that the transcriptome sequencing data were accurate and reliable. In addition, 22 potential hub miRNAs were screened. Dual luciferase reporter assays confirmed the targeting relationship between miR-144-y and DIO3. The results showed that the miRNAs mainly regulated the laying performance and brooding behavior of WWG by mediating the expression of target genes. In this study, we systematically elucidated the mechanisms by which the HPG axis regulates the broodiness behavior and laying performance of WWG at the post-transcriptional level. Several miRNAs and mRNAs associated with the reproductive performance of WWG were identified, providing a crucial reference for the subsequent use of gene editing technologies to breed new varieties and advance the development of WWG breeding industry.

Acrylamide-induced hypothalamic-pituitary-gonadal axis disruption in rats: Androgenic protective roles of apigenin by restoring testicular steroidogenesis through upregulation of 17β-HSD, CYP11A1 and CYP17A1

Acrylamide (ARL) exposure induces significant toxicity to the hypothalamic-pituitary-gonadal (HPG) axis, leading to detrimental effects on behavior, neuroendocrine functions, steroidogensis, oxidative stress, inflammation, hormonal balance, sperm quality, and histopathological integrity in rats. This study investigates the protective role of oral apigenin (API; 10 or 20 mg/kg/day for 28 days) against ARL-induced toxicity in the HPG axis of male Wistar rats. Behavioral assessments revealed that ARL exposure impaired motor coordination and balance, as evidenced by increased landing foot splay distance and gait score. ARL-induced toxicity elevated brain Tau protein levels and disrupted hypothalamic GnRH levels, both mitigated by API. ARL triggered oxidative/nitrosative stress, reducing GSH contents and increasing MDA and NO levels in brain and testicular tissues, which were reversed by API. Hormonal imbalance, marked by decreased serum testosterone, FSH, and LH levels, was corrected by API. API enhanced semen quality parameters, with elevation in sperm count concentration and the percentages of both progressive motility and individual motility. It also normalized testicular PS and PC content, enhanced testicular cellular energy and restored seminal amino acid. The repression of testicular steroidogenesis-related enzymes CYP11A1, CYP17A1, and 17β-HSD following ARL exposure was alleviated by API administration. API also mitigated the inflammatory effects of ARL by reducing the expression of p–NF–κB p65 and TNF-α in testicular tissue. Histopathological examinations showed that API reduced neuronal and testicular degeneration, improving spermatogenesis. These findings suggest that API confers significant protective effects against ARL-induced HPG axis toxicity by restoring testicular steroidogenesis through the upregulation of 17β-HSD, CYP11A1, and CYP17A1, potentially due to its antioxidant, anti-inflammatory, and neuroprotective properties.

The assessment of urinary sexual hormones within minipuberty and correlations with anthropometrics in a cohort of healthy term children.

Minipuberty follows different trends in boys and girls. Aim of our study was to explore timing and dynamics of minipuberty in healthy infants, analyzing urinary levels of sexual hormones. Moreover, we analyzed the association among HPG axis activity and linear growth, ano-genital distances (AGDs) in both sexes, and penile length in males. Longitudinal cohort study in healthy term infants from birth to 6 months of life. Clinical evaluation (anthropometrics and AGDs) and urine sampling were performed at 0 (T0), 3 (T3), and 6 (T6) months. Urine samples were analyzed for gonadotropins and sex hormones. 165 participants were involved. The growth trend of our population was regular, as were the AGDs. Urinary hormones were correlated each other's. Specifically, in boys, the correlation coefficient between urinary FSH (uFSH) and urinary LH (uLH) decreased from T0 to T6, while between urinary Testosterone (uT) and uFSH increased. In girls, correlations between uFSH and urinary Estradiol (uE) were observed at each time point. Notably, several correlations between hormones and anthropometrics and AGDs were found; the most interesting correlation was found in males within uLH and PL (at T0 ρ: 0.323, p < 0.05 and at T3 ρ: 0.371, p < 0.01), whereas in females uFSH at T0 showed negative correlations with both length and body weight percentile at T3 (ρ: -0.505, p < 0.01 and ρ: -0.478, p < 0.01, respectively). Urinary matrix has proved to be a valuable, practical, non-invasive and cheaper method for sexual hormone assessment.

Integrated transcriptomic hypothalamic-pituitary-ovarian axis network analysis reveals the role of energy availability on egg production in layers

Energy is a crucial component for maintaining egg production in layers. The hypothalamic-pituitary-ovarian (HPO) axis is an energy-sensitive functional axis for follicle development, synthesis, and secretion of reproductive hormones, and plays a key role in modulating sustained ovulation in layers. To investigate the mechanism of integrated network regulation of the HPO axis under energy fluctuation, ninety Hy-line brown layers (265-day-old, 1.92 ± 0.02 kg) were randomly divided into three groups for an 17-day experiment: a control group (Con group) fed ad libitum from days 1 to 17, an energy deprived group (ED group) that was fed ad libitum from days 1 to 12 and then underwent a fasting period from days 13 to 17 to induce a pause in laying, and a re-fed group (Rf group) that fasted for seven days (specifically, days 1 to 5, day 7, and day 9), had ad libitum access to feed on days 6 and 8, and were continuously fed from days 10 to 17. Each treatment consisted of 10 replicates with 3 birds per replicate. The study found that energy deprivation significantly decreased reproductive performance such as egg laying rate, ovarian index, number of small yellow follicles (SYF), and normal hierarchical follicles (NHIE) (P < 0.05), which recovered after refeeding, indicating the importance of energy availability for sustained ovulation in layers. In addition, estradiol (E2), estradiol/progesterone ratio (E2/P4), and luteinizing hormone (LH) displayed changes similar to follicle number, whereas follicle-stimulating hormone (FSH) exhibited a contrasting pattern. Transcriptome analysis revealed that energy deprivation downregulated genes related to energy and appetite-regulated neurotransmitter receptors and neuropeptides in the hypothalamus. These signals combined to inhibit gonadotropin-releasing hormone (GnRH) secretion and subsequently downregulated the crucial genes responsible for synthesizing gonadotropins, gonadotropin releasing hormone receptor (GnRHR), and glycoprotein hormones alpha chain (CGA). Consequently, this suppression of the hypothalamus and pituitary affected ovarian function through ovarian steroidogenesis and the extracellular matrix (ECM)-receptor interaction. These findings suggest that energy deprivation inhibits the function of the HPO axis, leading to impaired follicle development and reduced egg production and that refeeding can partially restore these indicators.

Multigenerational impact of chronic exposure to mercury chloride on maternal care, puberty, fertility, and hypothalamic function in female mice

Chronic exposure to low doses of mercury, one of the ten most dangerous chemicals for public health, has been associated with problems in fertility. Our study aims to investigate the effect of chronic exposure to a low dose of mercury chloride on the reproductive health of female mice and maternal behavior throughout generations using the maternal lineage for the first and second generations, either by direct exposure with F1 and F2 or via the germ cells with F2'. To our knowledge, these modalities have never been addressed before. Among the main outcomes of our research, we provide evidence that mercury exposure induces multigenerational alterations of maternal care and reproduction in female mice, respectively, through alterations of gene expression in the hypothalamus. The decline in maternal care behaviors observed in all exposed groups involved reduced nursing frequency and grooming/licking behaviors. The reproductive phenotype found across generations in our study directly exposed the F1 and F2, or even in the germline-exposed F2′, is defined by a delay in the vaginal opening, a delay in the first estrus, altered estrous cyclicity, and a decrease in interest in mating behavior observed in the two-choice preference test. These results were accompanied by a reduction in the mRNA expression of kiss1 and Gnrh1 in the hypothalamus, critical hormones in the HPG axis for initiating ovulation and estrous cycles. Furthermore, the F1, F2, and F2′ exposed mice had significantly decreased mRNA expression of Bdnf, which might indicate impaired communication within the neural circuits controlling reproduction. Additionally, increased Tnf-α and Il6 mRNA expression indicates a possible inflammatory response to mercury exposure across generations.

Revisiting the specific and potentially independent role of the gonad in hormone regulation and reproductive behavior.

Gonadal sex steroid hormones are well-studied modulators of reproductive physiology and behavior. Recent behavioral endocrinology research has focused on how the brain dynamically responds to - and may even produce - sex steroids, but the gonadal tissues that primarily release these hormones receive much less attention as a potential mediator of behavioral variation. This Commentary revisits mechanisms by which the reproductive hypothalamic-pituitary-gonadal (HPG) axis can be modulated specifically at the gonadal level. These mechanisms include those that may allow the gonad to be regulated independently of the HPG axis, such as receptors for non-HPG hormones, neural inputs and local production of conventional 'neuropeptides'. Here, I highlight studies that examine variation in these gonadal mechanisms in diverse taxa, with an emphasis on recent transcriptomic work. I then outline how future work can establish functional roles of gonadal mechanisms in reproductive behavior and evaluate gonad responsiveness to environmental cues. When integrated with neural mechanisms, further investigation of gonadal hormone regulation can yield new insight into the control and evolution of steroid-mediated traits, including behavior.

ALKBH5 Reduces BMP15 mRNA Stability and Regulates Bovine Puberty Initiation Through an m6A-Dependent Pathway.

The timing of puberty significantly influences subsequent reproductive performance in cattle. N6-methyladenosine (m6A) is a key epigenetic modification involved in the regulation of pubertal onset. However, limited research has investigated alterations in m6A methylation within the hypothalamic-pituitary-ovarian (HPO) axis during the onset of puberty. In this study, combined analysis of methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and RNA sequencing (RNA-seq) is used to describe the overall modification pattern of m6A in the HPO axis, while GSEA, KEGG, and GO analyses are used to describe the enrichment pathways of differentially expressed genes and differentially methylated genes. The m6A modifications of the differential genes KL, IGSF10, PAPPA2, and BMP15 and the pathways of cell adhesion molecules (CAMs), TGF-β, cell cycle, and steroid hormone synthesis may play roles in regulating the function of the HPO axis tissue during pubertal transition. Notably, BMP15's m6A modification depends on the action of the demethylase ALKBH5, which is recognized by the reader protein YTHDF2, promoting bovine granulosa cell proliferation, steroid production, and estrogen secretion. This study reveals for the first time the modification mechanism of BMP15 m6A during the initiation of bovine puberty, which will provide useful information for improving the reproductive efficiency of Chinese beef cattle.

The effect of cortisone on female zebrafish (Dania rerio): Reducing reproductive capacity and offspring survival rate

Cortisone is a naturally occurring corticosteroid hormone known for its wide range of anti-inflammatory and immunosuppressive effects, and it is commonly found in various aquatic environments. Previous reports have shown that cortisone can have significant negative impacts on fish; however, its specific effects on fish reproduction have not been thoroughly investigated. In this study, female adult zebrafish were exposed to 0.0 (control), 3.9, 40.2, and 377.9 ng/L of cortisone for 60 days, and multiple endpoints were evaluated. The results showed that as the concentration of cortisone increased, there was an increase in the percentage of perinuclear oocytes and a decrease in the proportion of late-stage oocytes, indicating a stagnation in oocyte development. Additionally, female zebrafish exposed to cortisone exhibited decreased attraction to males and reduced mating intimacy. Furthermore, exposure to cortisone resulted in changes in the development and behavior of zebrafish embryos. At cortisone concentrations of 3.9 and 40.2 ng/L, fewer eggs were laid and the survival rate of fertilized eggs decreased. These observed effects are associated with abnormal transcription levels of genes (Star, Cyp11a1, Cyp17, Cyp19a, Cyp11b, Hsd11β2, Hsd17β3) related to the HPG axis. These findings provided new insights into understanding potential environmental risks associated with corticosteroids.

Postnatal Dysregulation of Androgens in Extremely Preterm Male Infants.

Neurodevelopmental impairments are common among survivors of extremely preterm birth, particularly in males. Hyperactivation of the hypothalamic-pituitary-gonadal (HPG) axis has been suggested as an underlying cause, but this has been poorly investigated. Establish levels and temporal changes in circulating androgens in extremely preterm infant males. Observational cohort study analyzing cord blood serum (n = 25) and postnatal plasma (n = 13) collected from day 0 until week 11 from infant males born at 22.8-27.9 weeks gestational age. Testosterone and dihydrotestosterone (DHT) were determined using gas chromatography mass spectrometry, sex hormone-binding globulin (SHBG) with an enzyme-linked immunosorbent assay, and follicle-stimulating hormone (FSH) and luteinizing hormone (LH) with the Luminex xMAP multiplex assay. Testosterone and DHT levels were higher on day 0 (median 4.27 and 0.30 ng/mL) than in cord blood (0.15 and 0.01 ng/mL) (P < .001 for both). Levels of the hormones then declined rapidly until day 5 (median 0.16 and 0.12 ng/mL), then remained relatively constant throughout the study period. Median levels of testosterone and DHT across the whole study period were approximately 6-fold higher than reported in utero levels. FSH and LH showed similar postnatal patterns as the androgens. SHBG steadily increased over time, and, as a result, the fraction of bioavailable testosterone declined with infant postnatal age. The HPG axis is activated immediately after birth in extremely preterm infant males, resulting in an androgen pulse occurring several months earlier than during a normal pregnancy. The long-term implications of high androgen exposure during a sensitive neurodevelopmental period warrant further studies.

12212 A Rare Case Of Central Precocious Puberty In A Male Infant With Adrenal Hypoplasia Congenita

Abstract Disclosure: A. Mastoropoulou: None. A.H. Lane: None. Introduction: We describe a male with Adrenal Hypoplasia Congenita (AHC) caused by a novel mutation in NR0B1, who was noted at 9 months of age to have central precocious puberty (CPP). Clinical case: A 3 week-old full-term male presented with hypothermia and lethargy, and a 0.3 kg weight loss since birth. Labs were consistent with adrenal crisis: Na 109 mmol/L, K 10.4 mmol/L, Ca 12.2 mg/dL, glucose 43 mg/dL. He was stabilized with stress dose hydrocortisone (HC), insulin and antibiotics, and was admitted. Subsequent labs revealed cortisol 3.5 ug/dL (4.6-23), ACTH 1,123 pg/mL (7.2-63), 17OHP 181 ng/dL (&amp;lt;199), and a renin of 180 ng/mL/h (1.7-11.2) with aldosterone 14.9 ng/dL (6-179). Abdominal ultrasound was remarkable for non-visualization of the adrenal glands. The patient was discharged with HC, fludrocortisone and sodium supplementation with good tolerance and interval weight gain and normal electrolytes. Genetic testing identified a novel pathogenic c.707G&amp;gt;A [p.Trp236Ter] nonsense variant in the DNA-binding domain of NR0B1 (DAX-1). At 9 months of age, penile enlargement with prepubertal testes was noted. Testosterone was 318 ng/dL (Tanner stage I: 0-18), LH 3.2 mIU/mL (prepubertal: 0-0.3), DHEA-S 2 ug/dL (0-33), FSH 1.1 mIU/mL (prepubertal: 0-1), consistent with hypothalamic pituitary gonadal (HPG) axis activation. Given previous reports of prolonged but self-resolving “mini-puberty of infancy” in AHC, observation was initially chosen. At 12 months of age the bone age was consistent with the Greulich and Pyle 17 months standard. At 13 months of age testosterone remained elevated, therefore based on others’ reported experiences we increased HC from 8 to 15 mg/m2/day and noted a decrease in testosterone to 104 ng/dL within 5 days. HC was further increased to 18 mg/m2/day for 15 days, however testosterone increased to 270 ng/dL, therefore decision was made to treat with Lupron Depot. Conclusions: Historically, hypogonadotropic hypogonadism has been observed in 76% of adolescent patients with AHC who have alterations in NR0B1. CPP has been infrequently described in AHC, and the natural history and management of CPP in this setting is not established. CPP in AHC does not seem to correlate with any particular functional domain of DAX1, because previously reported NR0B1 variants associated with CPP, and this case’s, are dispersed across the gene. The course of our patient suggests multiple underlying mechanisms, including early HPG axis activation as well as the possibility of ACTH dependent precocious puberty. Our observations may contribute to the understanding of factors influencing normal and abnormal puberty in infants. Increased awareness of the possibility of CPP in AHC will aid clinicians in the earlier clinical and laboratory detection of this complication. Presentation: 6/1/2024

8698 Unique populations of pituitary macrophages regulate gonadotropin secretion

Abstract Disclosure: Z. Del Mundo: None. J. Ha: None. A. Zhang: None. K.D. Wiggins: None. G. De Robles: None. C. Garcia: None. N. Ujagar: None. D. Nicholas: None. Chronic inflammation disrupts hormonal balance in the Hypothalamic-Pituitary-Gonadal (HPG) axis, contributing to reproductive disorders. Despite extensive studies on immune cells in the hypothalamus and ovaries, their impact on the pituitary is largely unexplored. Our research reveals that macrophages are the primary immune population in the pituitary during homeostasis. In response to in vivo chronic lipopolysaccharide exposure in mice, a transient macrophage population emerges, associated with reproductive changes, including elevated serum testosterone, prolonged estrous cycle stage, and reduced ovarian antral follicle count. This study aims to characterize pituitary macrophages and elucidate their impact on the HPG axis. We hypothesize that pituitary macrophages change inflammatory status as a response to stimuli and, as a result, modulate gonadotropin secretion. We pinpointed differentially expressed genes (DEGs) in pituitary macrophages using scRNAseq, distinguishing them from other tissue-resident macrophages, including microglia. These DEGs include markers for macrophage activation, phagocytosis, migration, hormone synthesis, and lipid metabolism. Immunohistochemistry validated the distinctive morphology of pituitary macrophages compared to microglia. In vitro depletion of macrophages from mouse pituitaries resulted in decreased pituitary hormone secretion and decreased secretion of G-CSF, IL-9, and CXCL5. These results highlight the role of pituitary macrophages in hormonal regulation, setting the stage for future immunotherapeutic strategies to restore hormonal balance in reproductive disorders. Presentation: 6/3/2024

12333 46 XX/XY Chimerism - Positive NIPT And Post-natal Karyotype Is It Real?

Abstract Disclosure: K.L. Del Rosario: None. N. Sheriden: None. N. Vijayakanthi: None. Introduction: Non-Invasive Prenatal Testing(NIPT) using cell free fetal DNA in plasma of pregnant women has become a routine part of prenatal care in screening for fetal aneuploidies including sex chromosome abnormalities in most regions around the world. False positive results are increasingly imposing challenges in pre-natal as well as post-natal care. Case Discussion: We report a neonate born at 32+2 weeks gestation to a 42-year-old G2 P2 mother. Pregnancy was complicated by insulin dependent maternal type 2 diabetes mellitus, maternal chronic hypertension and a positive NIPT for high-risk monosomy X. Prenatal ultrasound showed male anatomy. Interestingly on physical exam after birth, the neonate had typical male external genitalia with bilateral normal male gonads. Chromosome analysis done immediately after birth revealed the presence of two cell lines: 40 of the 50 cells (80%) had a normal female 46 XX karyotype and 10 of the 50 cells (20%) had a normal male 46 XY karyotype. These findings could be due to reabsorbed twin, Klinefelter syndrome with two trisomy rescue events, maternal cell contamination or true chimerism. In addition, fluorescence in situ hybridization (FISH) analysis for X and Y probes revealed the presence of two cell lines. The first cell line (70% of the cells) had two hybridization signals for chromosome X and the second cell line (∼25% of the cells) had one hybridization signal for chromosome X and one for chromosome Y. Postnatal ultrasound showed normal testicles with no evidence of Mullerian structures. Newborn screening was negative for congenital adrenal hyperplasia (CAH). Genetics was consulted and recommended repeat chromosomal analysis, parental testing to determine sex chromosome segregation, and follow-up with pediatric endocrinology. Repeat cytogenetic testing at 2 weeks of life resulted in a normal male chromosome complement of 46,XY. Previous abnormal cytogenetics were thought to be due to maternal cell contamination. Further endocrine labs showed LH(1.16 uIU/ml) and testosterone levels ( 87 ng/dL), appropriate levels for age indicating normal Hypothalamic Pituitary Gonadal (HPG) axis and testicular Leydig cell function. Since the family was previously counseled regarding the concept of maternal cell contamination, they expressed understanding and were happy with the update of the normal karyotype result. Conclusion: False-positive results concerning for rare chimerism on NIPT can occur and should prompt a thorough history, physical exam, ultrasound studies and repeat testing to confirm its presence. Careful consideration should be taken when counseling family about the implications of these results, especially communication about gender assignment of the infant. Presentation: 6/3/2024

7438 DAX1/NR0B1 Related Adrenal Hypoplasia Congenita Without Hypogonadotropic Hypogonadism

Abstract Disclosure: R.L. Figueiredo: None. J.B. Drummond: None. A. Meireles: None. J.L. Machado: None. G. Vidigal: None. B.S. Rocha: None. Background: X-linked congenital adrenal hypoplasia (AHC) is a rare disease caused by genetic mutations in DXA1/NRB01 gene, which encodes a nuclear hormone receptor expressed in the adrenal cortex, gonads, hypothalamus and anterior pituitary gland, occurring in less than 1:12,500 live births (1,2). AHC is characterized by primary adrenal insufficiency (PAI) associated with hypogonadotropic hypogonadism (HH) and impaired spermatogenesis (oligospermia or azoospermia). Although DAX1/NR0B1 mutations can manifest with different phenotypes, HH is mostly present, which makes this present case a diagnostic challenge. Clinical case: A 23-year-old man presented with typical symptoms of adrenal insufficiency at the age of 7 (abdominal pain, dehydration, nausea, vomiting and cutaneous hyperpigmentation). Initial testing was consistent with primary adrenal failure: elevated ACTH levels (1250pg/mL, RR&amp;lt;46pg/mL) and very low serum cortisol (0.8mcg/dL, RR 3-20mcg/dL). Etiological investigation excluded autoimmune etiology (negative anti-adrenal and anti-21-hydroxylase antibodies) as well as adrenoleukodystrophy (normal very long chain fatty acid levels). Physical exam revealed normal virilization, testicular volume and penile length. The patient reported normal libido and sexual function. Hormonal evaluation showed normal total testosterone (424 and 713ng/dL, RR 165 to 753ng/dL) as well as calculated free testosterone (7.2 and 11.4ng/mL, RR&amp;gt;3.8ng/mL) levels. Abdominal CT showed signs of bilateral adrenal hypoplasia. We then proceeded to genetic testing that revealed a pathological variant c.625C&amp;gt;T:p (Gln 209*) in hemizygosity in exon 1 of the DAX 1/NR0B1 gene. This is a nonsense mutation that introduces a premature stop codon. This variant is not present on the global and Brazilian genetic databases (gnomAD and ABraOM) and has not been previously described in the literature. The patient is currently being treated for adrenal insufficiency with the lowest tolerated dose of prednisone (7.5mg/day) and fludrocortisone 0.1mg/day. Conclusion: Etiological investigation of patients with PAI is essential to understand the evolution of the disease, monitoring extra-adrenal manifestations and the possibility of genetic counseling for the family. An intact hypothalamic-pituitary gonadal axis should not preclude genetic evaluation for a DAX/NR0B1 mutation in patients with PAI and suspected AHC. Further studies will clarify if this specific mutation carries a genotype-phenotype correlation in patients with AHC without HH.