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Foland-Ross LC, Ghasemi E, Lozano Wun V, Aye T, Kowal K, Ross J, Reiss AL. Executive Dysfunction in Klinefelter Syndrome: Associations With Brain Activation and Testicular Failure. J Clin Endocrinol Metab 2023; 109:e88-e95. [PMID: 37595261 PMCID: PMC10735320 DOI: 10.1210/clinem/dgad487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 08/09/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
CONTEXT Executive dysfunction is a well-recognized component of the cognitive phenotype of Klinefelter syndrome (KS), yet the neural basis of KS-associated cognitive weaknesses, and their association with testicular failure is unknown. OBJECTIVE We investigated executive function, brain activation, and pubertal development in adolescents with and without KS. METHODS Forty-three adolescents with KS (mean age 12.3 ± 2.3 years) and 41 typically developing boys (mean age 11.9 ± 1.8 years) underwent pubertal evaluation, behavioral assessment, and completed functional magnetic resonance imaging (fMRI) as they performed an executive function task, the go/no-go task. Group differences in activation were examined. Associations among activation, executive function, and pubertal development measures were tested in secondary analyses. RESULTS Boys with KS exhibited reduced executive function, as well as lower activation in brain regions subserving executive function, including the inferior frontal gyrus, anterior insula, dorsal anterior cingulate cortex, and caudate nucleus. Secondary analyses indicated that the magnitude of activation differences in boys with KS was associated with severity of pubertal developmental delay, as indexed by lower testosterone (t(36) = 2.285; P = .028) and lower testes volume (t(36) = 2.238; P = .031). Greater parent-reported attention difficulties were additionally associated with lower testicular volume (t(36) = -2.028; P = .050). CONCLUSION These findings indicate a neural basis for executive dysfunction in KS and suggest alterations in pubertal development may contribute to increased severity of this cognitive weakness. Future studies that examine whether these patterns change with testosterone replacement therapy are warranted.
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Affiliation(s)
- Lara C Foland-Ross
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Elnaz Ghasemi
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
| | - Vanessa Lozano Wun
- Department of Psychology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tandy Aye
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 93405, USA
| | - Karen Kowal
- Department of Pediatrics, Nemours Children's Hospital Delaware, Wilmington, DE 19803, USA
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Judith Ross
- Department of Pediatrics, Nemours Children's Hospital Delaware, Wilmington, DE 19803, USA
- Department of Pediatrics, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Allan L Reiss
- Center for Interdisciplinary Brain Sciences Research, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94304, USA
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 93405, USA
- Department of Radiology, Stanford University School of Medicine, Stanford, CA 94304, USA
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Yuan F, Bai K, Hou Y, Zou X, Sun J. Small Molecule Cocktails Promote Fibroblast-to-Leydig-like Cell Conversion for Hypogonadism Therapy. Pharmaceutics 2023; 15:2456. [PMID: 37896216 PMCID: PMC10610100 DOI: 10.3390/pharmaceutics15102456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/07/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Male hypogonadism arises from the inadequate production of testosterone (T) by the testes, primarily due to Leydig cell (LC) dysfunction. Small molecules possess several advantages, including high cell permeability, ease of synthesis, standardization, and low effective concentration. Recent investigations have illuminated the potential of small molecule combinations to facilitate direct lineage reprogramming, removing the need for transgenes by modulating cellular signaling pathways and epigenetic modifications. In this study, we have identified a specific cocktail of small molecules, comprising forskolin, DAPT, purmorphamine, 8-Br-cAMP, 20α-hydroxycholesterol, and SAG, capable of promoting the conversion of fibroblasts into Leydig-like cells (LLCs). These LLCs expressed key genes involved in testosterone synthesis, such as Star, Cyp11a1, and Hsd3b1, and exhibited the ability to secrete testosterone in vitro. Furthermore, they successfully restored serum testosterone levels in testosterone-castrated mice in vivo. The small molecule cocktails also induced alterations in the epigenetic marks, specifically H3K4me3, and enhanced chromosomal accessibility on core steroidogenesis genes. This study presents a reliable methodology for generating Leydig-like seed cells that holds promise as a novel therapeutic approach for hypogonadism.
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Affiliation(s)
| | | | | | | | - Jie Sun
- Department of Urology, Shanghai Children’s Medical Center, Shanghai Jiao Tong University of Medicine, No. 1678 Dongfang Road, Pudong New Area, Shanghai 200127, China; (F.Y.); (K.B.); (Y.H.); (X.Z.)
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3
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Vogiatzi MG, Jaffe JS, Amy T, Rogol AD. Allometric Scaling of Testosterone Enanthate Pharmacokinetics to Adolescent Hypogonadal Males (IM and SC Administration). J Endocr Soc 2023; 7:bvad059. [PMID: 37180212 PMCID: PMC10174206 DOI: 10.1210/jendso/bvad059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Indexed: 05/16/2023] Open
Abstract
Context Intramuscular (IM) testosterone enanthate (TE) and testosterone pellets were US Food and Drug Administration approved before 1962 for pediatric use but not studied in controlled trials in adolescents. Objective An analysis using nonlinear mixed effect (NLME) modeling was designed to evaluate the adult pharmacokinetics (PK) of subcutaneous (SC) and IM TE. This model was used to simulate SC and IM TE administration in adolescents of different weight groups. Methods Data from adult male patients in a phase 2 trial were used to characterize the PK of TE using population PK modeling for SC and IM administration: Allometry was used to scale PK parameters from the adult model to simulate adolescent (aged 12 to < 18 years) serum testosterone levels at body weights of 30, 40, 50, and 60 kg after weekly, every-other-week (EOW), and monthly SC and IM administration of 12.5, 25, 50, 75, and 100 mg TE regimens. Results The final data set included 714 samples from 15 patients receiving 100 mg SC TE and 123 samples from 10 patients receiving 200 mg IM TE. In simulated populations, average serum concentration SC:IM ratios were 0.783, 0.776, and 0.757 at steady state for weekly, EOW, and monthly dosing groups, respectively. Simulated regimens of 12.5 mg SC TE monthly produced serum testosterone levels representative of early puberty and simulated pubertal stage progression following multiple subsequent testosterone dose increases. Conclusion SC TE administration achieved a testosterone exposure-response relationship similar to IM TE in simulated adolescent hypogonadal males, which may reduce size of fluctuations in serum T and related symptoms.
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Affiliation(s)
- Maria G Vogiatzi
- Correspondence: Maria G. Vogiatzi, MD, Adrenal and Puberty Center, Division of Endocrinology and Diabetes, Children’s Hospital of Philadelphia, 3401 Civic Center Blvd, Philadelphia, PA 19104-4399, USA.
| | - Jonathan S Jaffe
- Clinical Development and Medical Affairs, Antares Pharma Inc, Ewing, NJ 08628, USA
| | - Takugo Amy
- Department of Pharmacokinetics, Synteract Inc, a Syneos Health Company, Morrisville, NC 27560, USA
| | - Alan D Rogol
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
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4
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Kalra S, Jacob J, Unnikrishnan AG, Bantwal G, Sahoo A, Sahay R, Jindal S, Agrawal MS, Kapoor N, Saboo B, Tiwaskar M, Kochhar K. Expert Opinion on the Diagnosis and Management of Male Hypogonadism in India. Int J Endocrinol 2023; 2023:4408697. [PMID: 36876281 PMCID: PMC9977550 DOI: 10.1155/2023/4408697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 01/19/2023] [Accepted: 01/28/2023] [Indexed: 02/24/2023] Open
Abstract
Male hypogonadism (MH) is a clinical and biochemical syndrome caused by inadequate synthesis of testosterone. Untreated MH can result in long-term effects, including metabolic, musculoskeletal, mood-related, and reproductive dysfunction. Among Indian men above 40 years of age, the prevalence of MH is 20%-29%. Among men with type 2 diabetes mellitus, 20.7% are found to have hypogonadism. However, due to suboptimal patient-physician communication, MH remains heavily underdiagnosed. For patients with confirmed hypogonadism (either primary or secondary testicular failure), testosterone replacement therapy (TRT) is recommended. Although various formulations exist, optimal TRT remains a considerable challenge as patients often need individually tailored therapeutic strategies. Other challenges include the absence of standardized guidelines on MH for the Indian population, inadequate physician education on MH diagnosis and referral to endocrinologists, and a lack of patient awareness of the long-term effects of MH in relation to comorbidities. Five nationwide advisory board meetings were convened to garner expert opinions on diagnosis, investigations, and available treatment options for MH, as well as the need for a person-centered approach. Experts' opinions have been formulated into a consensus document with the aim of improving the screening, diagnosis, and therapy of men living with hypogonadism.
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Affiliation(s)
- Sanjay Kalra
- Department of Endocrinology, Bharti Hospital, Karnal 132001, Haryana, India
| | - Jubbin Jacob
- Department of Endocrinology, Christian Medical College and Hospital, Ludhiana 141008, Punjab, India
| | | | - Ganapathi Bantwal
- Department of Endocrinology, St Johns Medical College, Bengaluru 560034, Karnataka, India
| | - Abhay Sahoo
- Department of Endocrinology, Institute of Medical Sciences and SUM Hospital, Bhubaneswar 751003, Odisha, India
| | - Rakesh Sahay
- Department of Endocrinology, Osmania Medical College, Hyderabad 500095, Telangana, India
| | - Sushil Jindal
- People's Medical College and Research Centre, Bhopal 462037, Madhya Pradesh, India
| | - Madhu Sudan Agrawal
- Department of Urology, Global Rainbow Hospita, l, Agra 282007, Uttar Pradesh, India
| | - Nitin Kapoor
- Department of Endocrinology, Diabetes and Metabolism, Christian Medical College, Ida Scudder Road, Vellore 632004, Tamil Nadu, India
- Baker Heart and Diabetes Institute, Melbourne, Australia
| | - Banshi Saboo
- Department of Medicine, Dia Care, Ahmedabad 380015, Gujarat, India
| | - Mangesh Tiwaskar
- Department of Medicine, Shilpa Medical Research Centre, Mumbai 400068, Maharashtra, India
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Jabari M. Trans Dermal Testosterone Compared to Intramuscular Testosterone for Young Males with Delayed Puberty: A PRISMA Guided Systematic Review. Int J Gen Med 2023; 16:733-744. [PMID: 36872942 PMCID: PMC9984275 DOI: 10.2147/ijgm.s396144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 02/03/2023] [Indexed: 03/03/2023] Open
Abstract
Background Challenges in selecting the right formulation of testosterone (TE) for young males with delayed puberty (DP) arise from the fact that there is limited evidence based guidelines in recommending the most efficient and safe formulation of TE. Objective To evaluate the existing evidence and systematically review the interventional effects of transdermal TE to other modes of TE administration for the treatment of DP among young and adolescent males. Methods All types of methodologies published in English were searched from the data sources including MEDLINE, Embase, Cochrane Reviews, Web of Science, AMED and Scopus from 2015 till 2022. Boolean operators with keywords "types of TE", "modes of TE administration", "DP", "transdermal TE", "constitutional delay of growth and puberty, (CDGP)" "adolescent boys" and "hypogonadism" to optimize the search results. The main outcomes of concern were optimal serum TE level, body mass index, height velocity, testicular volume, pubertal stage (Tanner), The secondary outcomes included in this study were adverse events and patient satisfaction. Results After screening 126 articles, 39 full texts were reviewed. Only five studies could be included after careful screening and rigid quality assessments. Most studies were at high or unclear risk of bias with short duration and follow up periods. Only one study was a clinical trial covering all the outcomes of interests. Conclusion This study points out the favorable effects of transdermal TE treatment for DP in boys, while the existence of the vast gap in research needs to be acknowledged. Despite the utmost demand in an appropriate TE treatment for young males with DP, scarce efforts and trials are being undertaken to provide clear clinical guidance of treatment. Quality of life, cardiac events, metabolic parameters, coagulation profiles are important aspects of the treatment are overlooked and under evaluated in most studies. Systematic Review Registration PROSPERO CRD 42022369699.
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Affiliation(s)
- Mosleh Jabari
- Department of Endocrinology, College of Medicine, Imam Mohammad Ibn Saud Islamic University, Riyadh, Saudi Arabia
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6
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Abstract
INTRODUCTION Delayed puberty, defined as the appearance of pubertal signs after the age of 14 years in males, usually affects psychosocial well-being. Patients and their parents show concern about genital development and stature. The condition is transient in most of the patients; nonetheless, the opportunity should not be missed to diagnose an underlying illness. AREAS COVERED The aetiologies of pubertal delay in males and their specific pharmacological therapies are discussed in this review. EXPERT OPINION High-quality evidence addressing the best pharmacological therapy approach for each aetiology of delayed puberty in males is scarce, and most of the current practice is based on small case series or unpublished experience. Male teenagers seeking attention for pubertal delay most probably benefit from medical treatment to avoid psychosocial distress. While watchful waiting is appropriate in 12- to 14-year-old boys when constitutional delay of growth and puberty (CGDP) is suspected, hormone replacement should not be delayed beyond the age of 14 years in order to avoid impairing height potential and peak bone mass. When primary or central hypogonadism is diagnosed, hormone replacement should be proposed by the age of 12 years provided that a functional central hypogonadism has been ruled out. Testosterone replacement regimens have been used for decades and are fairly standardised. Aromatase inhibitors have arisen as an interesting alternative for boy with CDGP and short stature. Gonadotrophin therapy seems more physiological in patients with central hypogonadism, but its relative efficacy and most adequate timing still need to be established.
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Affiliation(s)
- Rodolfo A Rey
- Centro de Investigaciones Endocrinológicas "Dr. César Bergadá" (CEDIE), CONICET - FEI - División de Endocrinología, Hospital de Niños Ricardo Gutiérrez, C1425EFD Buenos Aires, Argentina.,Universidad de Buenos Aires, Facultad de Medicina, Departamento de Histología, Embriología, Biología Celular y Genética, C1121ABG Buenos Aires, Argentina
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7
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Abstract
Pediatric endocrinologists often evaluate and treat youth with delayed puberty. Stereotypically, these patients are 14-year-old young men who present due to lack of pubertal development. Concerns about stature are often present, arising from gradual shifts to lower height percentiles on the population-based, cross-sectional curves. Fathers and/or mothers may have also experienced later than average pubertal onset. In this review, we will discuss a practical clinical approach to the evaluation and management of youth with delayed puberty, including the differential diagnosis and key aspects of evaluation and management informed by recent review of the existing literature. We will also discuss scenarios that pose additional clinical challenges, including: (1) the young woman whose case poses questions regarding how presentation and approach differs for females vs males; (2) the 14-year-old female or 16-year-old young man who highlight the need to reconsider the most likely diagnoses, including whether idiopathic delayed puberty can still be considered constitutional delay of growth and puberty at such late ages; and finally (3) the 12- to 13-year-old whose presentation raises questions about whether age cutoffs for the diagnosis and treatment of delayed puberty should be adjusted downward to coincide with the earlier onset of puberty in the general population.
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Affiliation(s)
- Jennifer Harrington
- Division of Endocrinology, Women's and Children's Health Network, North Adelaide, 5006, Australia
- Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, 5000, Australia
| | - Mark R Palmert
- Division of Endocrinology, The Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada
- Departments of Pediatrics and Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
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8
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Suarez A MC, Israeli JM, Kresch E, Telis L, Nassau DE. Testosterone therapy in children and adolescents: to whom, how, when? Int J Impot Res 2022; 34:652-662. [PMID: 34997199 DOI: 10.1038/s41443-021-00525-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/17/2021] [Accepted: 12/21/2021] [Indexed: 11/09/2022]
Abstract
Male production of testosterone is crucial for the development of a wide range of functions. External and internal genitalia formation, secondary sexual characteristics, spermatogenesis, growth velocity, bone mass density, psychosocial maturation, and metabolic and cardiovascular profiles are closely dependent on testosterone exposure. Disorders in androgen production can present during all life-stages, including childhood and adolescence, and testosterone therapy (TT) is in many cases the only treatment that can correct the underlying deficit. TT is controversial in the pediatric population as hypoandrogenism is difficult to classify and diagnose in these age groups, and standardized protocols of treatment and monitorization are still lacking. In pediatric patients, hypogonadism can be central, primary, or a combination of both. Testosterone preparations are typically designed for adults' TT, and providers need to be aware of the advantages and disadvantages of these formulations, especially cognizant of supratherapeutic dosing. Monitoring of testosterone levels in boys on TT should be tailored to the individual patient and based on the anticipated duration of therapy. Although clinical consensus is lacking, an approximation of the current challenges and common practices in pediatric hypoandrogenism could help elucidate the broad spectrum of pathologies that lie behind this single hormone deficiency with wide-ranging implications.
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Affiliation(s)
- Maria Camila Suarez A
- Department of Urology, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | | | - Leon Telis
- Department of Urology, Lenox Hill Hospital, Donald and Barbra Zucker School of Medicine at Hofstra/Northwell, New York, NY, USA
| | - Daniel E Nassau
- Department of Pediatric Urology, Nicklaus Children's Hospital, Miami, FL, USA.
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Alsaffar H, Habeb A, Hamza RT, Deeb A. Monitoring Haematocrit in Paediatric Patients Receiving Testosterone Therapy in Arab Countries. Cureus 2021; 13:e17618. [PMID: 34646669 PMCID: PMC8483389 DOI: 10.7759/cureus.17618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2021] [Indexed: 11/11/2022] Open
Abstract
Objectives Testosterone is the main agent used to induce puberty in boys in Arab countries. It is recommended to monitor haematocrit before and during androgen replacement. However, data from single centre studies indicated that this recommendation is rarely practiced by paediatricians compared to adult physicians. The aim of this study is to evaluate the monitoring of haematocrit of patients on Testosterone therapy by paediatric endocrinologists practicing in Arab countries. Methods A cross-sectional study using an online survey that was sent to all members of the Arab Society for Paediatric Endocrinology and Diabetes (ASPED), who they practice in all Arab countries. The study was carried out between July and October 2019. Ethical approval was granted by ASPED council in May 2019 (MRE2019-02Q). Results One hundred four physicians responded to the survey from 17 countries. 81/104 (77.8%) answered the question about Testosterone monitoring (42 paediatric endocrinologists, 11 general paediatrician consultants with interest in endocrine, 16 specialists, four fellows and eight residents). Of the 81 responders 18 clinicians (22.2%) thought of monitoring the haematocrit; 15 (18.5%) thought no laboratory monitoring is needed at all. Conclusion The survey indicated that most paediatric endocrinologists in Arab countries do not monitor haematocrit in patients on testosterone replacement and majority are not aware that secondary erythrocytosis can result from androgen therapy. Raising the awareness on monitoring haematocrit during androgen replacement therapy is needed especially when reaching the adult dose.
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Affiliation(s)
- Hussain Alsaffar
- Child Health Department - Paediatric Endocrinology Unit, Sultan Qaboos University Hospital, Muscat, OMN
| | - Abdelhadi Habeb
- Paediatric Department, Prince Mohammed Bin Abdulaziz Hospital, Ministry of National Guard, Madinah, SAU
| | - Rasha T Hamza
- Faculty of Medicine, Ain Shams University, Cairo, EGY
| | - Asma Deeb
- Paediatric Endocrinology Department, Shaikh Shakhbout Medical City, Abu Dhabi, ARE
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10
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Roberts SA, Carswell JM. Growth, growth potential, and influences on adult height in the transgender and gender-diverse population. Andrology 2021; 9:1679-1688. [PMID: 33969625 PMCID: PMC9135059 DOI: 10.1111/andr.13034] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 05/03/2021] [Accepted: 05/03/2021] [Indexed: 12/30/2022]
Abstract
The sexually dimorphic trait of height is one aspect of the experience of transgender and gender‐diverse (TGD) individuals that may influence their gender dysphoria and satisfaction with their transition. In this article, we have reviewed the current knowledge of the factors that contribute to one's final adult height and how it might be affected in TGD youth who have not experienced their gonadal puberty in the setting of receiving gonadotropin‐releasing hormone analog (GnRHa) and gender‐affirming hormonal treatment. Additional research is needed to characterize the influence of growth and final adult height on the lived experience of TGD youth and adults and how to best assess their growth, predict their final adult height, and how medical transition can be potentially modified to help them meet their goals.
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Affiliation(s)
- Stephanie A Roberts
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Jeremi M Carswell
- Division of Endocrinology, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
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Abstract
Puberty, which in humans is considered to include both gonadarche and adrenarche, is the period of becoming capable of reproducing sexually and is recognized by maturation of the gonads and development of secondary sex characteristics. Gonadarche referring to growth and maturation of the gonads is fundamental to puberty since it encompasses increased gonadal steroid secretion and initiation of gametogenesis resulting from enhanced pituitary gonadotropin secretion, triggered in turn by robust pulsatile GnRH release from the hypothalamus. This chapter reviews the development of GnRH pulsatility from before birth until the onset of puberty. In humans, GnRH pulse generation is restrained during childhood and juvenile development. This prepubertal hiatus in hypothalamic activity is considered to result from a neurobiological brake imposed upon the GnRH pulse generator resident in the infundibular nucleus. Reactivation of the GnRH pulse generator initiates pubertal development. Current understanding of the genetics and physiology of the brake will be discussed, as will hypotheses proposed to account for timing the resurgence in pulsatile GnRH and initiation of puberty. The chapter ends with a discussion of disorders associated with precocious or delayed puberty with a focus on those with etiologies attributed to aberrant GnRH neuron anatomy or function. A pediatric approach to patients with pubertal disorders is provided and contemporary treatments for both precocious and delayed puberty outlined.
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Affiliation(s)
- Selma Feldman Witchel
- Pediatric Endocrinology, UPMC Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, United States.
| | - Tony M Plant
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh, Pittsburgh, PA, United States
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