Mammary Gland Development Research Articles

Identification of Goat Supernumerary Teat Phenotype Using Wide-Genomic Copy Number Variants

Supernumerary teats (SNTs) or nipples often emerge around the mammary line. This study performed a genome-wide selective sweep analysis (GWS) at the copy number variant (CNV) level using two selected signal calculation methods (VST and FST) to identify candidate genes associated with SNTs in goats. A total of 12,310 CNVs were identified from 37 animals and 123 CNVs, with the top 1% VST values including 84 candidate genes (CDGs). Of these CDGs, minichromosome maintenance complex component 3, ectodysplasin A receptor associated via death domain, and cullin 5 demonstrated functions closely related to mammary gland development. In addition, 123 CNVs with the top 1% FST values were annotated to 97 CDGs. 5-Hydroxytryptamine receptor 2A, CCAAT/enhancer-binding protein alpha, and the polymeric immunoglobulin receptor affect colostrum secretion through multiple signaling pathways. Two genes, namely, RNA-binding motif protein 46 and β-1,3-galactosyltransferase 5, showed a close relation to mammary gland development. Six CNVs were identified and annotated to five genes by intersecting the top 1% of candidate CNVs with both parameters. These genes include LOC102185621, LOC102190481, and UDP-glucose pyrophosphorylase 2, which potentially affect the occurrence of BC through multiple biological processes, such as cell detoxification, glycogen synthesis, and phospholipid metabolism. In conclusion, we discovered numerous genes related to mammary development and breast cancer (BC) through a GWS, which suggests the mechanism of SNTs in goats and a certain association between mammary cancer and SNTs.

The Potential Health Risks and Benefits of Progesterone in the Transgender Woman Population—A Narrative Review

Introduction: Currently, progesterone is notably absent from conventional feminizing hormone therapies for transgender women. Anecdotal reports indicate the potential for health advantages following the incorporation of progesterone into treatment regimens. The primarily female hormone, progesterone naturally surges in women during the menstrual luteal phase. When administered exogenously, it may expedite bodily changes that are pivotal for gender transition. Progesterone holds promise as a potential remedy for various health conditions prevalent in the transgender woman population. Methods: This narrative review synthesizes existing literature and presents a comprehensive account of the administration of exogenous progesterone in transgender women. A literature search was conducted using the PubMed, Embase, ScienceDirect, and ResearchGate databases. The following keywords were used in the search: progesterone, transgender, breast neoplasms, lactation, prostate, testicular neoplasms, and thrombosis. These terms were combined using Boolean operators. The results of the initial search were screened by three independent reviewers based on their relevance to the topic under study. Results: A total of 104 studies were initially identified as meeting the criteria for inclusion. Following an assessment based on the contents of the title, abstract, and full text, 39 studies were deemed eligible for inclusion. A critical examination of health outcomes was conducted across key sections, including breast development, mental health, lactation, cancer risk (breast and prostate), thrombosis, and nervous and other systems. Discussion: The use of progesterone in the transgender woman population is a topic that has yet to be sufficiently researched. The limited sample size, short follow-up periods, and lack of randomization restrict the potential for achieving a robust scientific evidence base. In order to gain a fuller understanding of this topic, findings from studies on contraception, hormone replacement therapy, and animal models were considered. Conclusions: Progesterone may have a beneficial effect on the bodies of transgender women without significant adverse health effects. Further investigation through well-designed studies is recommended. Randomized controlled trials that include various dosages, broad and long-term effects, and precise demographics are needed. There is an immediate need for more knowledge to create appropriate patent and clinical practice guidelines.

Additives in Processed Foods as a Potential Source of Endocrine-Disrupting Chemicals: A Review

Processed foods, accounting for most consumable food categories today, contain considerable amounts of food additives. Food additives are substances added to food products to improve taste, consistency, appearance, or shelf life. Various food additives, such as phthalates, bisphenol A, tartrazine, erythrosine, artificial sweeteners, and parabens, have been identified as potential sources of endocrine-disrupting chemicals (EDCs) in processed foods. EDCs are substances that frequently interfere with the regular functioning of the endocrine system, creating an unusual environment in the biological system, which leads to adverse health effects such as the disruption of hormone synthesis, receptor binding, and signal transduction pathways, as well as energy metabolic homeostatic disorders which potentially increasing the risk of obesity, type-2 diabetes, cardiometabolic diseases and may also trigger allergic reactions. Consequently, they can also impact mammary gland development, and reproductive function, further leading to developmental abnormalities. This review aims to insights into the various food additives that act as potential endocrine-disrupting chemicals (EDCs) and to describe their applications in the food industry, as well as the failure of hormonal homeostatic mechanisms, which eventually result in hazardous health effects. It also outlines strategies to reduce the use of food additives and suggests alternative additives with minimal or no endocrine-disrupting properties, highlighting their importance for maintaining human health.

Premature Thelarche: An Updated Review.

Premature thelarche is the most common pubertal disorder in girls. The condition should be differentiated from central precocious puberty which may result in early epiphyseal fusion and reduced adult height, necessitating treatment. The purpose of this article is to familiarize physicians with the clinical manifestations of premature thelarche and laboratory tests that may help distinguish premature thelarche from central precocious puberty. A search was conducted in September 2022 in PubMed Clinical Queries using the key term "Premature thelarche". The search strategy included all clinical trials, observational studies, and reviews published within the past 10 years. Only papers published in the English literature were included in this review. The information retrieved from the above search was used to compile the present article. Premature thelarche denotes isolated breast development before the age of 8 years in girls who do not manifest other signs of pubertal development. The condition is especially prevalent during the first two years of life. The majority of cases of premature thelarche are idiopathic. The condition may result from an unsuppressed hypothalamic-pituitary-gonadal axis in the early years of life, an "overactivation" of the hypothalamic-pituitary axis in early childhood secondary to altered sensitivity to steroids of the hypothalamic receptors controlling sexual maturation, increased circulating free estradiol, increased sensitivity of breast tissue to estrogens, and exposure to exogenous estrogens. The cardinal feature of premature thelarche is breast development which occurs without additional signs of pubertal development in girls under 8 years of age. The enlargement may involve only one breast, both breasts asymmetrically, or both breasts symmetrically. The breast size may fluctuate cyclically. The enlarged breast tissue may be transiently tender. There should be no significant changes in the nipples or areolae and no pubic or axillary hair. The vulva, labia majora, labia minora, and vagina remain prepubertal. Affected girls have a childlike body habitus and do not have mature contours. They are of average height and weight. Growth and osseous maturation, the onset of puberty and menarche, and the pattern of adolescent sexual development remain normal. Most cases of premature thelarche can be diagnosed on clinical grounds. Laboratory tests are seldom indicated. No single test can reliably differentiate premature thelarche from precocious puberty. Premature thelarche is benign, and no therapy is necessary apart from parental reassurance. As enlargement of breasts may be the first sign of central precocious puberty, a prolonged follow- up period every 3 to 6 months with close monitoring of other pubertal events and linear growth is indicated in all instances.

Environmental endocrine disrupting chemical-DEHP exposure-provoked biotoxicity about microbiota-gut-mammary axis in lactating mice via multi-omics technologies

Plastics, pervasive in humans and nature, often contain Di (2-ethylhexyl) phthalate (DEHP) that enhance plastic’s elasticity. However, DEHP is an environmental endocrine disruptor, affecting organisms upon exposure. Understanding mammary gland development in lactating females is crucial for offspring nourishment and dairy production. Employing multi-omics technology, this study aimed to uncover DEHP’s impact on the microbial–gut–mammary axis. Forty mice were exposed to varying DEHP doses for 18 d. We performed 16S sequencing, metabolomics, mammary tissue observation, and gene expression profiling. Results revealed DEHP’s influence on microbial diversity, with increased Lactobacillus abundance and reduced Proteobacteria, alongside colonic inflammation. Elevated GMP and adenosine 5′-monophosphate levels in the bloodstream were noted, while ascorbic acid, glycitein, and others decreased. MEHP, a DEHP metabolite, damaged mammary tissues, inhibiting ERK1/2 phosphorylation, triggering apoptosis and ferroptosis. These findings unveil potential therapeutic targets for DEHP-induced chronic toxicity in humans and animals, aiding dairy livestock health and human well-being. This study underscores the importance of understanding the adverse effects of DEHP exposure on mammalian systems.

Association of STAT1 gene with milk fat and protein yield in Holstein Friesian crossbred cattle maintained in the sub-tropical climate of India.

Signal transducers and activators of transcription (STAT) genes are involved in signal mediation of various hormones and cytokines. STAT1 located on chromosome number 2 is involved in mammary gland development and is associated with milk composition traits in bovines. This study aimed to find any relationship and impact of STAT1/BspHI gene with milk fat and protein yields in a herd of Holstein Friesian (HF) crossbred cattle of sub-tropical climate of Northern India. Milk composition data of 535 adult HF crossbred cows for a period of 12 years was collected from the records maintained at Livestock Farm, Guru Angad Dev Veterinary and Animal Sciences University. First lactation data of 222 animals was chosen for further analysis. After data correction for non-genetic factors (season of calving, period of calving, interaction effect of season and period of calving and age at first calving) these animals were categorised into two groups based on corrected high and low milk fat and protein yields. Forty animals were then selected for blood collection and further laboratory analysis. Amplified using PCR-RFLP technique, the 314 bp STAT1 gene was digested using BspHI restriction enzyme. C-T polymorphism at nucleotide position 201 and 260 of the STAT1 amplicon was observed. At 201, for genotype AA and Aa, the genotypic frequencies were 0.80 and 0.20%. At 260, for genotype BB and Bb, the genotypic frequencies were 0.25 and 0.75%. Least square analysis showed a significant association of all genotypes with milk fat and protein yields. Hence, STAT1 can be used as a potential candidate gene to aid in better animal selection in breeding programmes.

Sorted stem/progenitor epithelial cells of pubertal bovine mammary gland present limited potential to reconstitute an organised mammary epithelium after transplantation.

The development and maintenance of mammary gland tissue depend on the proliferation and differentiation of mammary stem and progenitor cells. Here, we investigated populations of mammary epithelial cells that are potential candidates for bovine mammary gland development using xenotransplantation into mice cleared mammary fat pad. Transplanted mammary explants from 17-month-old Holstein heifers developed outgrowths exhibiting the archetypal morphology and molecular marker distributions of the bovine gland. Xenotransplantation of sorted mammary epithelial cells (CD49fpos) into bovinised fat pads using inactivated bovine fibroblasts resulted in outgrowth developments with 50% take rate, but these lacked the ductal or alveolar epithelial structures of the normal mammary gland. Similar results were obtained with xenografts of candidate bovine mammary epithelial stem cells (CD49fhighCD24pos) or epithelial cells of the basal lineage (CD49fhighCD24neg) which also developed as clumps of cells surrounded by stromal stretches within the mouse adipose tissue. In conclusion, sorted cells showed compromised regenerative potential for epithelial morphogenesis. Further work is therefore needed to identify mammary stem/progenitor cells with full regenerative capabilities for biogenesis of normal mammary gland structure, with milk-secreting function.

A Phase3, Open-Label, Single-Arm Trial of the Efficacy and Safety of Triptorelin 6-Month Formulation in Chinese Children with Central Precocious Puberty.

This phase3 study assessed the efficacy, safety, and pharmacokinetics of the 6-month prolonged release (PR) formulation in Chinese children with central precocious puberty (CPP). In this open-label study (NCT05029622), Chinese children (girls < 9years, boys < 10years) received two doses of triptorelin pamoate 22.5mg (day1 and month6). Primary endpoint was the proportion at month6 with luteinizing hormone (LH) suppression (stimulated peak LH ≤ 5IU/L after gonadotropin-releasing hormone stimulation). Secondary endpoints included safety assessments, hormone level changes, and clinical parameters from baseline. Overall, 66 children completed the study (93.9% girls; median age 8.0 [range 5-9] years). At month6, all patients had LH suppression; this was maintained at month12 in 98.5% of patients. Mean basal and peak LH and follicle-stimulating hormone levels were suppressed throughout follow-up. All patients at months3 to 12had sex hormone suppression to prepubertal levels. Stable or reduced breast development was seen for 98.4% and 93.5% of girls at month6 and 12, respectively; all boys had regression or stable genital development until month12. Compared with baseline (9.82cm/year), mean growth velocity was 5.88cm/year at month6 and 5.17cm/year at month12. Mean bone age/chronological age ratio decreased from 1.27 at baseline to 1.23 and 1.21 at month6 and 12, respectively. In girls, 64.5% showed decreased uterine length at month6 and 12 versus baseline, while 75.0% of boys showed stable testicular volume versus baseline. Thirteen patients (19.7%) had 22 drug-related treatment emergent adverse events (TEAEs); no grade ≥ 3 TEAEs were reported. The efficacy and safety profile of triptorelin 6-month PR in Chinese children with CPP was consistent with data previously reported in non-Chinese children with CPP, supporting this as a viable treatment option for Chinese children with CPP. Trial registration:ClinicalTrials.gov identifier, NCT05029622.

Osteocalcin: may be a useful biomarker for early identification of rapidly progressive central precocious puberty in girls.

To assess serum osteocalcin (OC) as a potential biomarker for the early detection of rapidly progressive central precocious puberty (RP-CPP) in girls. Serum OC levels were quantified using enzyme-linked immunosorbent assays (ELISAs). In the retrospective analysis, receiver operating characteristic (ROC) curve analysis was employed to evaluate the ability of OC to identify RP-CPP. A prospective study and screening tests were utilized to assess the potential of OC for use in the early prediction of RP-CPP. Variable selection in the multivariate analysis was conducted using the Bayesian Information Criterion (BIC) and binary logistic regression was employed to construct the diagnostic prediction model. Girls with RP-CPP had significantly higher serum OC levels compared to girls with non-rapidly progressive central precocious puberty (NRP-CPP) (149.04±40.50 vs. 89.10±31.83 ng/mL, P < 0.001). The optimal OC cut-off point for differentiating RP-CPP from NRP-CPP was 107.05 ng/mL, the area under the ROC curve (AUC) was 0.90 (95%CI: 0.851-0.949; P < 0.001), with a sensitivity of 91.1% and specificity of 70.7%. The results of the prospective study indicated that changes in OC precede alterations in estradiol (E2) and bone age (BA). A diagnostic prediction model that includes duration of breast development, BA, OC, high-density lipoprotein cholesterol (HDL-C), and uterine length achieved an AUC of 0.961, with a sensitivity of 94.1% and specificity of 91.5% for the detection of RP-CPP. If OC is excluded from the model, the AUC decreases to 0.894, with sensitivity and specificity declining to 80.5% and 83.1%, respectively. Serum OC levels may serve as a promising biomarker for the early differentiation between RP-CPP and NRP-CPP in girls. The diagnostic prediction model that incorporates duration of breast development, BA, OC, HDL-C, and uterine length effectively identifies girls with RP-CPP.

Pilot Study on the Effect of Patient Condition and Clinical Parameters on Hypoxia-Induced Factor Expression: HIF1A, EPAS1 and HIF3A in Human Colostrum Cells.

Hypoxia-inducible factor 1 (HIF-1) may play a role in mammary gland development, milk production and secretion in mammals. Due to the limited number of scientific reports on the expression of HIF genes in colostrum cells, it was decided to examine the expression of HIF1A, HIF3A and EPAS1 in the these cells, collected from 35 patients who voluntarily agreed to provide their biological material for research, were informed about the purpose of the study and signed a consent to participate in it. The expression of HIF genes was assessed using qPCR. Additionally, the influence of clinical parameters (method of delivery, occurrence of stillbirths in previous pregnancies, BMI level before pregnancy and at the moment of delivery, presence of hypertension during pregnancy, presence of Escherichia coli in vaginal culture, iron supplement and heparin intake during pregnancy) on the gene expression was assessed, revealing statistically significant correlations. The expression of HIF1A was 3.5-fold higher in the case of patients with the presence of E. coli in vaginal culture (p = 0.041) and 2.5 times higher (p = 0.031) in samples from women who used heparin during pregnancy. Approximately 1.7-fold higher expression of the EPAS1 was observed in women who did not supplement iron during pregnancy (p = 0.046). To our knowledge, these are the first studies showing the relationship between HIF expression in cells from breast milk and the method of delivery and health condition of women giving birth. The assessment of HIF expression requires deeper examination in a larger study group, and the results of further studies will allow to determine whether HIF can become biomarkers in pregnancy pathology states.

In Vitro Screening of Trehalose Synbiotics and Their Effects on Early-Lactating Females and Offspring Mice.

Activities such as childbirth and breastfeeding can cause severe oxidative stress and inflammatory damage to the mother during early lactation, and can affect animal milk production, and the growth and development of offspring. Trehalose alleviates damage to the body by endowing it with stress resistance. In this study, we used trehalose combined with Lactobacillus plantarum, Bifidobacterium longum, Bacillus subtilis, and Saccharomyces cerevisiae to explore whether dietary intervention can alleviate oxidative stress and inflammatory damage in early lactation and to evaluate the growth ability, acid production ability, antioxidant ability, non-specific adhesion ability, antibacterial ability, and other parameters to determine the optimal combinations and proportions. The results showed that the synbiotics composed of 2.5% trehalose and 1 × 107 cfu/g of Bifidobacterium longum could regulate the gut microbiota, and promote mammary gland development in dams by reducing progesterone (PROG) content in the blood, increasing prolactin (PRL) and insulin-like growth factor-1 (IGF-1) content, enhancing their antioxidant and immune abilities, and effectively increasing the weight and lactation of early lactating dams. In addition, it can also affect the growth of offspring and the development of the intestinal barrier. These results indicate that trehalose synbiotics have great potential in alleviating oxidative stress and inflammatory damage in early lactation.

Hepatic-derived extracellular vesicles in late pregnancy promote mammary gland development by stimulating prolactin receptor-mediated JAK2/STAT5/mTOR signalling

The mammary glands develop rapidly in late pregnancy to prepare adequately for lactation. At this stage the liver is crucial for mammary gland development, and it can achieve distal mammary gland regulation through hepatic factors and hormones. Recently, an increasing number of studies have found that hepatic-derived extracellular vesicles play an essential role in organ-to-organ communication, however, its effect on mammary gland development remains unclear. In this study, we extracted hepatic-derived extracellular vesicles from pregnant (P-hEVs) and non-pregnant mice (NP-hEVs), respectively, and explored their regulatory role on mammary gland development. The results revealed that P-hEVs was able to promote the proliferation and differentiation of HC11 cells. In addition, intraperitoneal injection of P-hEVs into pubertal female mice increased mammary gland weight and promoted mammary gland development. Mechanistically, P-hEVs activated the PI3K/AKT signalling pathway to enhance the proliferation of mammary epithelial cells, and also activated prolactin receptor-mediated JAK2/STAT5/mTOR signalling to promote mammary epithelial cell lactation and the synthesis of milk proteins and milk lipids. Overall, mouse liver during pregnancy can transmit signals to the mammary gland in the form of extracellular vesicles to promote its development and provide for subsequent lactation.

12330 Progestogen Experience And Perception Among Transfeminine Adults - A National Survey

Abstract Disclosure: J.J. Chang: None. N. Khai Tran: None. A. Flentje: None. M.E. Lubensky: None. J. Obedin-Maliver: Consulting Fee; Self; Ibis Reproductive Health, Hims, Incorporated, Folx, Incorporated, Upstream, Incorporated. M.R. Lunn: Consulting Fee; Self; Hims, Incorporated, Otsuka Pharmaceutical Development and Commercialization, Inc., American Dental Association. D. Ariel: None. Background: Current guidelines recommend estradiol with consideration of anti-androgens for gender-affirming hormone therapy (GAHT) in transfeminine adults. Many individuals also seek progestogens as part of feminizing GAHT, particularly to enhance breast development. Though progestogen use seems common, few studies describe its use, reported benefits, and side effects. SpecificAims: 1) To describe progestogen use in feminizing GAHT among transfeminine individuals in the U.S. 2) To evaluate reasons for progestogen initiation and perceived physical and emotional impact; 3) To investigate side effects and adverse events. Materials and Methods: In this cross-sectional study, participants were recruited from The PRIDE Study, a U.S.-based longitudinal cohort study of LGBTQIA+-identifying adults. Included participants were assigned male sex at birth and had a feminine/transfeminine or non-binary gender identity. Those assigned female sex at birth (AFAB) or born with 1 or more ovaries were excluded. Descriptive statistics were used to describe socio-demographic characteristics, progestogen use patterns, initiation reasons, perceived physical and mental impacts, side effects, adverse events, and care satisfaction. Results: 543 participants were eligible and completed the study. Mean age was 43.2 years (standard deviation: 14.9). Of 310 progestogen users, the most common progestogen forms were micronized progesterone (58.4% oral; 10.6% rectal) and medroxyprogesterone acetate (7.7% oral). Median progestogen use duration was 2 years (interquartile range: 1-4). Breast development (85.2%) and mimicking the hormone pattern of those AFAB (58.1%) were the two most reported reasons for progestogen initiation. Most progestogen users reported improved breast development (79.7%); none reported worsening. Sex drive, sleep, and concentration did not change with progestogen use in 46.5%, 51.3%, and 73.9% of participants, respectively. Adverse events included lower extremity deep vein thrombosis (n = 6) and pulmonary embolism (n = 4). The most common side effects were breast pain (28.7%), mood fluctuation (21.9%), fatigue (19.7%), and weight gain (19.0%). Most users expressed satisfaction with progestogens (71.9%) and would recommend to others (73.5%). Among 68 former progestogen users, 20.6% reported stopping progestogens due to negative side effects, and 32.4% stopped due to lack of perceived efficacy. Conclusions: In the largest study describing progestogens in GAHT to date, over half of transfeminine adults used progestogens, particularly for breast development. Most reported improvement with breast development and overall satisfaction. However, perceived impacts on other effects were variable. Future prospective studies are needed to investigate the effects of progestogens versus other components of feminizing GAHT. Presentation: 6/1/2024

12330 Progestogen Experience And Perception Among Transfeminine Adults - A National Survey

Abstract Disclosure: J.J. Chang: None. N. Khai Tran: None. A. Flentje: None. M.E. Lubensky: None. J. Obedin-Maliver: Consulting Fee; Self; Ibis Reproductive Health, Hims, Incorporated, Folx, Incorporated, Upstream, Incorporated. M.R. Lunn: Consulting Fee; Self; Hims, Incorporated, Otsuka Pharmaceutical Development and Commercialization, Inc., American Dental Association. D. Ariel: None. Background: Current guidelines recommend estradiol with consideration of anti-androgens for gender-affirming hormone therapy (GAHT) in transfeminine adults. Many individuals also seek progestogens as part of feminizing GAHT, particularly to enhance breast development. Though progestogen use seems common, few studies describe its use, reported benefits, and side effects. SpecificAims: 1) To describe progestogen use in feminizing GAHT among transfeminine individuals in the U.S. 2) To evaluate reasons for progestogen initiation and perceived physical and emotional impact; 3) To investigate side effects and adverse events. Materials and Methods: In this cross-sectional study, participants were recruited from The PRIDE Study, a U.S.-based longitudinal cohort study of LGBTQIA+-identifying adults. Included participants were assigned male sex at birth and had a feminine/transfeminine or non-binary gender identity. Those assigned female sex at birth (AFAB) or born with 1 or more ovaries were excluded. Descriptive statistics were used to describe socio-demographic characteristics, progestogen use patterns, initiation reasons, perceived physical and mental impacts, side effects, adverse events, and care satisfaction. Results: 543 participants were eligible and completed the study. Mean age was 43.2 years (standard deviation: 14.9). Of 310 progestogen users, the most common progestogen forms were micronized progesterone (58.4% oral; 10.6% rectal) and medroxyprogesterone acetate (7.7% oral). Median progestogen use duration was 2 years (interquartile range: 1-4). Breast development (85.2%) and mimicking the hormone pattern of those AFAB (58.1%) were the two most reported reasons for progestogen initiation. Most progestogen users reported improved breast development (79.7%); none reported worsening. Sex drive, sleep, and concentration did not change with progestogen use in 46.5%, 51.3%, and 73.9% of participants, respectively. Adverse events included lower extremity deep vein thrombosis (n = 6) and pulmonary embolism (n = 4). The most common side effects were breast pain (28.7%), mood fluctuation (21.9%), fatigue (19.7%), and weight gain (19.0%). Most users expressed satisfaction with progestogens (71.9%) and would recommend to others (73.5%). Among 68 former progestogen users, 20.6% reported stopping progestogens due to negative side effects, and 32.4% stopped due to lack of perceived efficacy. Conclusions: In the largest study describing progestogens in GAHT to date, over half of transfeminine adults used progestogens, particularly for breast development. Most reported improvement with breast development and overall satisfaction. However, perceived impacts on other effects were variable. Future prospective studies are needed to investigate the effects of progestogens versus other components of feminizing GAHT. Presentation: 6/1/2024

5065 Cyproterone Acetate Versus Spironolactone In Transgender Women Commencing Estradiol: A Randomized Controlled Trial

Abstract Disclosure: L.M. Angus: Advisory Board Member; Self; Kirin Brewery. Speaker; Self; Kirin Brewery. S. Leemaqz: None. A. Kasielska-Trojan: None. M. Mikołajczyk: None. J. Doery: None. J.D. Zajac: None. A.S. Cheung: None. Background: Transgender women commonly use cyproterone acetate or spironolactone as anti-androgens with estradiol to assist with feminization. However, the optimal anti-androgen is unclear. We aimed to assess the effect of these anti-androgens on breast development and hypothesized that cyproterone acetate would result in greater breast development than spironolactone due to greater androgen receptor antagonism and suppression of serum total testosterone. Design: Double-blind, randomised controlled trial Methods: Transgender women newly commencing estradiol were randomized to spironolactone 100mg daily or cyproterone acetate 12.5mg daily for six months. The primary outcome was measurement of breast development via breast chest distance with secondary outcomes of estimated breast volume using the BreastIdea Volume Estimator application and serum total testosterone using LCMS. Results: Fifty-five participants were included in per protocol analysis (cyproterone acetate group n=28, spironolactone group n=27). Baseline age, body mass index, breast indices, serum estradiol and serum total testosterone were comparable. At six months, the mean (standard deviation) breast chest distance was 9.2cm (3.0) in the cyproterone group versus 8.3cm (2.7) in the spironolactone group (p=0.27). The mean (SD) estimated breast volume was 190.25 mL (158.60) in the cyproterone acetate group and 157.84mL (112.03) in the spironolactone group (p=0.39) with significant inter-individual variation (range 20.27 - 787.77 mL). The mean (SD) serum total testosterone was 1.48 nmol/L (3.45) in the cyproterone acetate group and 4.29 nmol/L (5.44) in the spironolactone group (p=0.04). Serum estradiol levels were comparable. Use of cyproterone acetate was associated with mild hyperprolactinaemia and spironolactone with an increase in serum urea and creatinine. Conclusions: Choice of anti-androgen should be individualised based on clinician and patient preference, with consideration of associated side effects. Further research is needed to optimise breast development in transgender women. Presentation: 6/3/2024

6480 Variability in Breast Development in Response to Exogenous Estrogen in Girls

Abstract Disclosure: T.M. Kurman: None. E.A. Eugster: None. Intro: Adolescents requiring treatment with exogenous estrogen (E2) include girls with primary and secondary hypogonadism and transfeminine youth. While 17B-estradiol is standard of care, the starting dose and escalation schedule are individualized. To what degree the response to E2 as assessed by breast Tanner stage is correlated with the dose is unknown. Similarly, whether the response to E2 varies depending on the underlying diagnosis has not been systematically analyzed. We aimed to investigate relationships between diagnosis, E2 dose, and breast Tanner staging in adolescent girls. Methods: We conducted a chart review of girls treated with E2 followed at our Pediatric Endocrine clinic between 2008-2022. Inclusion criteria included girls who were prepubertal at baseline and on a single increment of a 25 mcg E2 patch changed 2X/week from initiation of treatment to the first follow up visit. Only transgender girls being treated with a GnRH analog were included. Within each group of patients on the same starting dose, a Kruskal-Wallis test was conducted to evaluate differences in Tanner stage between diagnostic groups. Spearman’s correlation was used to evaluate the relationship between starting dose and Tanner stage. Finally, we evaluated differences within the Turner syndrome (TS) group for girls with monosomy X vs a mosaic karyotype. Results: Of 1,899 medical records, 70 eligible patients were identified. Of these, 33 (47.2%) had TS, 17 (24.3%) had primary ovarian insufficiency (POI), 15 (21.4%) had hypogonadotropic hypogonadism (HH), and 5 (7.1%) were transgender (TG). Twenty-three (32.9%) started on 1/4 patch (6.25 mcg), 29 (41.4%) on 1/2 patch (12.5 mcg) and 18 (25.7%) on a full patch (25 mcg). Girls on other regimens (e.g., 1/8 patch worn only at night) were excluded from analysis. The first f/u visit occurred at a median of 6 months (range 3-12 months). All TG girls were started on 25 mcg E2, which was significantly different compared to the other groups (p=0.002, p=0.005, and p=0.005 for TS, POI, and HH respectively). Breast Tanner stage at the first f/u visit ranged from 1-4 with no significant difference within each dose group based on diagnosis. However, a significant correlation between E2 dose and breast Tanner stage at f/u was seen in girls with HH (r=0.601, p=0.018). No effect of karyotype (monosomy X vs mosaic) on response to E2 in girls with TS was seen. Conclusion: There was striking variability in the starting dose of E2 in the vast majority of patients, highlighting the lack of standardization in clinical management. Interestingly, we found significant individual variability in terms of breast development in response to the initial dose of E2, regardless of diagnosis. Factors responsible for the unpredictable nature of the response to exogenous E2 are unexplored. Our findings provide important and novel prognostic information for patients and providers. Presentation: 6/1/2024

8548 Breast Development in Infant Girls: Does Endogenous Estrogen Production During Minipuberty Play a Role?

Abstract Disclosure: M. Goldberg: None. S. Zhao: None. A. Kelly: None. V.A. Stallings: None. D.M. Umbach: None. W.J. Rogan: None. N. Shaw: None. D.P. Sandler: None. Background: Breast tissue, present at birth in most term infants, regresses during infancy but persists longer in girls than boys. In girls, this persistence is thought to be due in part to stimulation by estradiol (E2) produced during minipuberty, the postnatal activation of the hypothalamic-pituitary-gonadal axis. Empirical data are sparse, however. Because E2 concentrations in infant girls fluctuate, repeated E2 measures may be necessary to adequately characterize production across minipuberty and to detect effects on estrogen-sensitive breast tissue. Hypothesis: Higher average exposure to E2 during minipuberty is associated with larger breast bud diameter in late infancy in term females. Methods: We leveraged data from 136 girls from the Infant Feeding and Early Development (IFED) Study, a prospective cohort of reproductive development in term infants enrolled during 2010-2013 from the Philadelphia area. We measured E2 in serum samples collected at study visits every 2-4 weeks from age 2-32 weeks. We assessed breast bud diameter via ultrasound at the 32-week visit. For data analysis, we log2-transformed both E2 and breast bud diameter. For E2 concentrations below the limit of detection (2.99 pg/mL, 35% of samples), we applied multiple imputation. We first calculated the intraclass correlation coefficient (ICC) of repeated E2 to understand the relative magnitude of total variation from within subjects. We then calculated subject-specific mean of E2 across time and estimated associations with breast bud diameter at the 32-week visit using both age- and multivariable-adjusted linear regression models. We present results as percent change in breast bud diameter per doubling in average E2 concentration ([2β-1] x 100%). Results: Most infants were Black (71%) and formula-fed (76%). The median number of E2 measures per girl was 9 (range: 5-10). Most of the variation in E2 concentrations was due to within-individual variation (ICC=0.27). The geometric mean E2 concentration from 2-32 weeks of age was 5.1 pg/mL (95% confidence interval [CI]: 4.7-5.4). The median breast bud diameter at the 32-week visit was 13.7mm (range: 4.4-30.5). A doubling in average E2 concentration across minipuberty was associated with a 26% larger breast bud diameter (95% CI 10-43%). This association was similar after adjustment for feeding method, race, gestational age, neonatal weight, and breast bud diameter at the neonatal visit (percent change: 28%, 95% CI: 12-46%). Conclusions: Our results suggest that endogenous estrogen production in females during minipuberty stimulates the infant breast bud. More research is needed to investigate the potential biologic relevance of this hormonal stimulation of infant breast tissue to later breast development and risk of malignant and benign breast disorders. Presentation: 6/1/2024

6941 Congenital Generalized Lipodystrophy - An Undiagnosed Case in an Underserved Border Community

Abstract Disclosure: D. Evans: None. A. Gutierrez: None. S. Echetebu: None. M. Zerah: None. Introduction: Congenital Generalized Lipodystrophy (Berardinelli-Seip Syndrome) is estimated to occur 1-10/10 million people1. Patients may present with specific clinical features and/or hormonal imbalances such as hyperinsulinemia and hypertriglyceridemia. Complications of CGL result in a decreased average life expectancy of 51.2 years2. Here we present a case of a female from a medically underserved city in Mexico who was not diagnosed until the age of 16, three years after immigration to the United States. Case Presentation: The patient lived in Mexico and had little medical care. After she immigrated, she was referred to Pediatric Endocrinology due to an elevated hemoglobin A1c, hypertriglyceridemia, and elevated liver enzymes. At birth and in adolescence, the patient did not resemble any of her five fully biological siblings, had little adipose tissue, and had well-defined musculature. Physical exam findings included generalized absence of adipose tissue and prominent musculature, large hands and feet, acromegaloid features, acanthosis nigricans, hirsutism, and phlebomegaly. Breast development was Tanner Stage IV, and genitalia was Tanner Stage V, without clitoromegaly. Patient is currently being treated by psychiatry for Major Depressive Disorder and suicidal ideation. Results: She was diagnosed with diabetes mellitus due to elevated glucose on OGGT and hypertriglyceridemia. She was then started on a low carbohydrate diet, Metformin, and Atorvastatin. After treatment a significant improvement in labs were observed. Triglyceride levels decreased from 1112 mg/dL to 392 mg/dL(35-150 mg/dL), A1c from 8.5% to 5.8%(&amp;lt;5.8%), AST from 36 U/L to 16 U/L(12-32U/L), and ALT from 51 U/L to 20 U/L(5-32U/L). OGGT levels measured after treatment began were as follows: fasting: 95 mg/dL (70-100mg/dL), 1 hour: 242 mg/dL (130-140 mg/dL), and 2 hours: 229 mg/dL(&amp;lt;155 mg/dL). A liver ultrasound was normal. Genetic testing, Echocardiogram, EKG, and Leptin levels are all pending. Discussion/Conclusion: This case of an adolescent with CGL, who was not diagnosed until 16 years of age, demonstrates not only the health disparities and challenges faced by patients in border communities, but it also demonstrates the lack of knowledge of CGL in healthcare. By presenting this case, we hope to increase awareness of CGL within the medical community at large, and to improve the quality of life of our patients.

7407 Normosmic Idiopathic Hypogonadotropic Hypogonadism in Women: A Case Report and Comprehensive Review

Abstract Disclosure: E.G. Bustamante: None. M. Sulehri: None. I. Patoli: None. A. Karunakaran: None. Normosmic Idiopathic Hypogonadotropic Hypogonadism (nIHH) in Women: A Case Report and Literature ReviewIntroduction: IHH is a rare genetic disorder affecting gonadotropic-releasing hormone (GnRH) production and/or action, resulting in diminished sex steroid levels. Characterized by the absence of spontaneous pubertal development. In women, it manifests with normal adrenarche but absent thelarche and menarche. Our case highlight a late diagnosis of IHH in a 34-year-old woman with primary amenorrhea. Case report: A 34 year old lady with a history of primary amenorrhea sought evaluation. At age 16, she underwent assessment for short stature and primary amenorrhea, denying anosmia, headache, visual disturbances. Evaluation revealed bone age concordant with chronological age and normal MRI Brain. Pelvic ultrasound (US) showed small premenarchal uterus and ovaries. She initiated oral contraceptive pills (OCP) and experienced regular menses. Seeking fertility assistance at age 24, a normal Hysterosalpingogram was followed by successful delivery of twins after ovarian stimulation. Post-delivery menses did not resume and OCP was not restarted. Family history revealed a sister with irregular periods requiring OCP.Subsequently workup at age 30 showed Estradiol 22 pg/ml, FSH/LH 4.1/2.3 mUI/mL; normal PRL, TFT, DHEAS, 17OHP. Repeat Pelvic US showed normal uterus, endometrial stripe normal at 0.24 cm and non-visualized ovaries. PCOS testing negative for hyperandrogenism. Progesterone challenge resulted in no withdrawal bleeding. Brain MRI demonstrated a 2.2 x 1.3 mm hypoenhancing ovoid mass in the pars Intermedia of the pituitary gland suggestive of pituitary microadenoma. Pituitary axis hormonal testing was normal. Karyotype revealed 46 XX (normal female). Genetic evaluation identified a pathogenic variant (p.R35C) in GNRH1 gene. Her final diagnosis: nIHH. Discussion HH is diagnosed in 5% of all women with primary amenorrhea and is divided into 2 major categories: Kallmann syndrome and nIHH. The majority of known causes of HH can be attributed to mutations in KAL1, FGFR1, or GNRHR. The p.R35C variant has been associated with autosomal dominant nIHH. Diagnosis involves clinical suspicious, low LH/FSH and sex steroid levels, normal hypothalamic–pituitary imaging, and exclusion of differentials.Treatment goal for female focus on regular breast and uterine development, as well as the capability to conceive. Use of hormonal replacement therapy and/or gonadotropins or pulsatile GnRH for ovarian stimulation are essential. ConclusionWhile IHH predominantly affects men, limited literature explores its manifestation in women and its impact on fertility. The identification of a GNRH1-related nIHH variant highlights the role of genetic testing in specific HH diagnoses. Failure to diagnose in adolescence may compromise women overall well-being Presentation: 6/1/2024

Proteomic and Transcriptomic Profiling Revealed Vital Molecular Events in the Transition from Goat Colostrum to Mature Milk.

As an important nutrient source in large areas of the world, goat milk is favored by more and more consumers; however, the composition, nutritional value, and regulation mechanism of goat milk are not fully characterized. Mammary gland development is as important as detailed annotation of protein composition to address the physiological and nutritional values of goat milk. In the present study, 4353 colostrum and mature goat milk proteins were identified. The abundance of 118 proteins was significantly different between colostrum and mature milk proteins. Our results indicate that the milk protein changes were associated with a network of mammary gene expression changes; importantly, the prime factors include enhanced mammary growth/development, decreased protein translation, attenuated protein folding, and lower lip/carbohydrate metabolism. The present study provides insights into the changes in mammary metabolisms during the transition from colostrum to mature milk, which can help deeply explore the difference and regulation mechanism of active milk protein in colostrum and mature milk and provide references for the identification and functional study of bioactive milk proteins in colostrum.