1
|
Venkatesh VS, Nie T, Golub S, Stok KS, Hemmatian H, Desai R, Handelsman DJ, Zajac JD, Grossmann M, Davey RA. High circulating concentrations of estradiol are anabolic for bone mass and strength in an adult male to female transgender mouse model. Bone 2024; 186:117143. [PMID: 38866125 DOI: 10.1016/j.bone.2024.117143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/29/2024] [Accepted: 05/31/2024] [Indexed: 06/14/2024]
Abstract
The effects of gender affirming hormone therapy (GAHT) on bone microarchitecture and fracture risk in adult transgender women is unclear. To investigate the concept that skeletal integrity and strength in trans women may be improved by treatment with a higher dose of GAHT than commonly prescribed, we treated adult male mice with a sustained, high dose of estradiol. Adult male mice at 16 weeks of age were administered ~1.3 mg estradiol by silastic implant, implanted intraperitoneally, for 12 weeks. Controls included vehicle treated intact females and males. High-dose estradiol treatment in males stimulated the endocortical deposition of bone at the femoral mid-diaphysis, increasing cortical thickness and bone area. This led to higher stiffness, maximum force, and the work required to fracture the bone compared to male controls, while post-yield displacement was unaffected. Assessment of the material properties of the bone showed an increase in both elastic modulus and ultimate stress in the estradiol treated males. Treatment of male mice with high dose estradiol was also anabolic for trabecular bone, markedly increasing trabecular bone volume, number and thickness in the distal metaphysis which was accompanied by an increase in the histomorphometric markers of bone remodelling, mineralizing surface/bone surface, bone formation rate and osteoclast number. In conclusion, a high dose of estradiol is anabolic for cortical and trabecular bone in a male to female transgender mouse model, increasing both stiffness and strength. These findings suggest that increasing the current dose of GAHT administered to trans women, while considering other potential adverse effects, may be beneficial to preserving their bone microstructure and strength.
Collapse
Affiliation(s)
- Varun S Venkatesh
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia; Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia.
| | - Tian Nie
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia.
| | - Suzanne Golub
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia.
| | - Kathryn S Stok
- Department of Biomedical Engineering, University of Melbourne, Parkville, Victoria 3010, Australia.
| | - Haniyeh Hemmatian
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia.
| | - Reena Desai
- ANZAC Research Institute, University of Sydney and Andrology, Concord Repatriation General Hospital, Concord, New South Wales 2137, Australia.
| | - David J Handelsman
- ANZAC Research Institute, University of Sydney and Andrology, Concord Repatriation General Hospital, Concord, New South Wales 2137, Australia.
| | - Jeffrey D Zajac
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia.
| | - Mathis Grossmann
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia; Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia.
| | - Rachel A Davey
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria 3084, Australia.
| |
Collapse
|
2
|
Hold LA, Phillips T, Cordts P, Steltzer S, Bae SH, Henry B, Migotsky N, Grossman S, Cruz CD, Padmanabhan V, Moravek M, Shikanov A, Abraham AC, Killian ML. Functional Changes to Achilles Tendon and Enthesis in a Mouse Model of an Adolescent Masculine Gender-Affirming Hormone Treatment. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.10.598308. [PMID: 38915724 PMCID: PMC11195120 DOI: 10.1101/2024.06.10.598308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Many transgender youth seek gender affirming care, such as puberty suppression, to prolong decision-making and to align their physical sex characteristics with their gender identity. During peripubertal growth, connective tissues such as tendon rapidly adapt to applied mechanical loads (e.g., exercise) yet if and how tendon adaptation is influenced by sex and gender affirming hormone therapy during growth remains unknown. The goal of this study was to understand the how pubertal suppression influences the structural and functional properties of the Achilles tendon using an established mouse model of transmasculine gender affirming hormone therapy. C57BL/6N female-born mice were assigned to experimental groups to mimic gender-affirming hormone therapy in human adolescents, and treatment was initiated prior to the onset of puberty (at postnatal day 26, P26). Experimental groups included controls and mice serially treated with gonadotropin release hormone analogue (GnRHa), delayed Testosterone (T), or GnRHa followed by T. We found that puberty suppression using GnRHa, with and without T, improved the overall tendon load capacity in female-born mice. Treatment with T resulted in an increase in the maximum load that tendon can withstand before failure. Additionally, we found that GnRHa, but not T, treatment resulted in a significant increase in cell density at the Achilles enthesis.
Collapse
Affiliation(s)
- LeeAnn A. Hold
- Department of Molecular and Integrative Physiology, Michigan Medicine, Ann Arbor Michigan, United States
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Tessa Phillips
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
- University of Toledo College of Medicine, Toledo, Ohio, United States
| | - Paige Cordts
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Steph Steltzer
- Department of Molecular and Integrative Physiology, Michigan Medicine, Ann Arbor Michigan, United States
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Seung-Ho Bae
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Brandon Henry
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
- Michigan State College of Osteopathic Medicine, East Lansing, MI, United States
| | - Nicole Migotsky
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Sydney Grossman
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Cynthia Dela Cruz
- Department of Biomedical Engineering, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Vasantha Padmanabhan
- Department of Biomedical Engineering, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Molly Moravek
- Department of Biomedical Engineering, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Ariella Shikanov
- Department of Biomedical Engineering, Michigan Medicine, Ann Arbor, Michigan, United States
- Department of Obstetrics and Gynecology, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Adam C. Abraham
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| | - Megan L. Killian
- Department of Molecular and Integrative Physiology, Michigan Medicine, Ann Arbor Michigan, United States
- Department of Orthopedic Surgery, Michigan Medicine, Ann Arbor, Michigan, United States
| |
Collapse
|
3
|
Pal S, Morgan X, Dar HY, Gacasan CA, Patil S, Stoica A, Hu YJ, Weitzmann MN, Jones RM, Pacifici R. Gender-affirming hormone therapy preserves skeletal maturation in young mice via the gut microbiome. J Clin Invest 2024; 134:e175410. [PMID: 38530358 DOI: 10.1172/jci175410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 03/20/2024] [Indexed: 03/27/2024] Open
Abstract
Gender-affirming hormone therapy (GAHT) is often prescribed to transgender (TG) adolescents to alleviate gender dysphoria, but the effect of GAHT on the growing skeleton is unclear. We found GAHT to improve trabecular bone structure via increased bone formation in young male mice and not to affect trabecular structure in female mice. GAHT modified gut microbiome composition in both male and female mice. However, fecal microbiota transfers (FMTs) revealed that GAHT-shaped gut microbiome was a communicable regulator of bone structure and turnover in male, but not in female mice. Mediation analysis identified 2 species of Bacteroides as significant contributors to the skeletal effects of GAHT in male mice, with Bacteroides supplementation phenocopying the effects of GAHT on bone. Bacteroides have the capacity to expand Treg populations in the gut. Accordingly, GAHT expanded intestinal Tregs and stimulated their migration to the bone marrow (BM) in male but not in female mice. Attesting to the functional relevance of Tregs, pharmacological blockade of Treg expansion prevented GAHT-induced bone anabolism. In summary, in male mice GAHT stimulated bone formation and improved trabecular structure by promoting Treg expansion via a microbiome-mediated effect, while in female mice, GAHT neither improved nor impaired trabecular structure.
Collapse
Affiliation(s)
- Subhashis Pal
- Division of Endocrinology, Metabolism and Lipids, Department of Medicine and
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
| | - Xochitl Morgan
- Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Hamid Y Dar
- Division of Endocrinology, Metabolism and Lipids, Department of Medicine and
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
| | - Camilo Anthony Gacasan
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics and
| | - Sanchiti Patil
- Division of Endocrinology, Metabolism and Lipids, Department of Medicine and
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
| | - Andreea Stoica
- Division of Endocrinology, Metabolism and Lipids, Department of Medicine and
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
| | - Yi-Juan Hu
- Department of Biostatistics and Bioinformatics, Emory University, Atlanta, Georgia, USA
| | - M Neale Weitzmann
- Division of Endocrinology, Metabolism and Lipids, Department of Medicine and
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
- Atlanta VA Healthcare System, Atlanta, Georgia, USA
| | - Rheinallt M Jones
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics and
| | - Roberto Pacifici
- Division of Endocrinology, Metabolism and Lipids, Department of Medicine and
- Emory Microbiome Research Center, Emory University, Atlanta, Georgia, USA
- Immunology and Molecular Pathogenesis Program, Emory University, Atlanta, Georgia, USA
| |
Collapse
|
4
|
Gu Y, Tang GT, Cheung ASZ, Sebaratnam DF. Dermatological considerations for transgender and gender diverse patients: An Australian perspective. Australas J Dermatol 2024; 65:24-36. [PMID: 37919972 DOI: 10.1111/ajd.14179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/04/2023] [Accepted: 10/08/2023] [Indexed: 11/04/2023]
Abstract
Transgender and gender diverse (TGD) individuals are a group that experiences significant health disparities. In the multidisciplinary management of TGD patients, dermatologists may participate in managing skin- and hair-related issues which contribute to gender affirmation and to the cutaneous sequelae of gender-affirming hormone therapy. This review aims to highlight the unique needs of TGD patients, particularly from the perspective of Australian dermatologists. We review appropriate terminology critical for TGD care, gender affirmation in the Australian healthcare landscape, dermatological considerations for TGD patients and considerations for management.
Collapse
Affiliation(s)
- Yaron Gu
- Faculty of Medicine and Health, The University of New South Wales, Kensington, New South Wales, Australia
- Department of Dermatology, Liverpool Hospital, Liverpool, New South Wales, Australia
| | - Gia Toan Tang
- Trans Health Research Group, Department of Medicine (Austin Health), The University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Ada Sau-Zhuen Cheung
- Trans Health Research Group, Department of Medicine (Austin Health), The University of Melbourne, Heidelberg, Victoria, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia
| | - Deshan Frank Sebaratnam
- Faculty of Medicine and Health, The University of New South Wales, Kensington, New South Wales, Australia
- Department of Dermatology, Liverpool Hospital, Liverpool, New South Wales, Australia
| |
Collapse
|
5
|
Henry BW, Cruz CD, Goulet RW, Nolan BT, Locke C, Padmanabhan V, Moravek MB, Shikanov A, Killian ML. Bone quality following peripubertal growth in a mouse model of transmasculine gender-affirming hormone therapy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.08.570840. [PMID: 38106067 PMCID: PMC10723410 DOI: 10.1101/2023.12.08.570840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
During peri-puberty, bone growth and the attainment peak bone mass is driven predominantly by sex steroids. This is important when treating transgender and gender diverse youth, who have become increasingly present at pediatric clinics. Analogues of gonadotropin-releasing hormone (GnRH) are commonly prescribed to transgender and gender diverse youth prior to starting gender-affirming hormone therapy (GAHT). However, the impact of GnRH agonists on long bones with the addition of GAHT is relatively unknown. To explore this, we developed a trans-masculine model by introducing either GnRHa or vehicle treatment to female-born mice at a pre-pubertal age. This treatment was followed by male GAHT (testosterone, T) or control treatment three weeks later. Six weeks after T therapy, bone quality was compared between four treatment groups: Control (vehicle only), GnRHa-only, GnRHa + T, and T-only. Bone length/size, bone shape, mechanical properties, and trabecular morphology were modulated by GAHT. Independent of GnRHa administration, mice treated with T had shorter femurs, larger trabecular volume and increased trabecular number, higher trabecular bone mineral density, and wider superstructures on the surface of bone (e.g., third trochanters) when compared to control or GnRHa-only mice. In conclusion, prolonged treatment of GnRHa with subsequent GAHT treatment directly affect the composition, parameters, and morphology of the developing long bone. These findings provide insight to help guide clinical approaches to care for transgender and gender diverse youth.
Collapse
Affiliation(s)
- Brandon W. Henry
- Department of Orthopaedic Surgery, Michigan Medicine, Ann Arbor, Michigan
- College of Osteopathic Medicine, Michigan State University, East Lansing, Michigan
| | - Cynthia Dela Cruz
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Robert W. Goulet
- Department of Orthopaedic Surgery, Michigan Medicine, Ann Arbor, Michigan
| | - Bonnie T. Nolan
- Department of Orthopaedic Surgery, Michigan Medicine, Ann Arbor, Michigan
| | - Conor Locke
- Department of Orthopaedic Surgery, Michigan Medicine, Ann Arbor, Michigan
| | - Vasantha Padmanabhan
- Department of Pediatrics, Michigan Medicine, Ann Arbor, Michigan
- Department of Obstetrics and Gynecology, Michigan Medicine, Ann Arbor, Michigan
| | - Molly B. Moravek
- Department of Obstetrics and Gynecology, Michigan Medicine, Ann Arbor, Michigan
| | - Ariella Shikanov
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
- Department of Obstetrics and Gynecology, Michigan Medicine, Ann Arbor, Michigan
| | - Megan L. Killian
- Department of Orthopaedic Surgery, Michigan Medicine, Ann Arbor, Michigan
| |
Collapse
|
6
|
Nie T, Venkatesh VS, Golub S, Stok KS, Hemmatian H, Desai R, Handelsman DJ, Zajac JD, Grossmann M, Davey RA. Estradiol increases cortical and trabecular bone accrual and bone strength in an adolescent male-to-female mouse model of gender-affirming hormone therapy. Bone Res 2024; 12:1. [PMID: 38212599 PMCID: PMC10784310 DOI: 10.1038/s41413-023-00308-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/28/2023] [Accepted: 12/05/2023] [Indexed: 01/13/2024] Open
Abstract
The effects of gender-affirming hormone therapy on the skeletal integrity and fracture risk in transitioning adolescent trans girls are unknown. To address this knowledge gap, we developed a mouse model to simulate male-to-female transition in human adolescents in whom puberty is first arrested by using gonadotrophin-releasing hormone analogs with subsequent estradiol treatment. Puberty was suppressed by orchidectomy in male mice at 5 weeks of age. At 3 weeks post-surgery, male-to-female mice were treated with a high dose of estradiol (~0.85 mg) by intraperitoneal silastic implantation for 12 weeks. Controls included intact and orchidectomized males at 3 weeks post-surgery, vehicle-treated intact males, intact females and orchidectomized males at 12 weeks post-treatment. Compared to male controls, orchidectomized males exhibited decreased peak bone mass accrual and a decreased maximal force the bone could withstand prior to fracture. Estradiol treatment in orchidectomized male-to-female mice compared to mice in all control groups was associated with an increased cortical thickness in the mid-diaphysis, while the periosteal circumference increased to a level that was intermediate between intact male and female controls, resulting in increased maximal force and stiffness. In trabecular bone, estradiol treatment increased newly formed trabeculae arising from the growth plate as well as mineralizing surface/bone surface and bone formation rate, consistent with the anabolic action of estradiol on osteoblast proliferation. These data support the concept that skeletal integrity can be preserved and that long-term fractures may be prevented in trans girls treated with GnRHa and a sufficiently high dose of GAHT. Further study is needed to identify an optimal dose of estradiol that protects the bone without adverse side effects.
Collapse
Affiliation(s)
- Tian Nie
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Varun S Venkatesh
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Suzanne Golub
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Kathryn S Stok
- Department of Biomedical Engineering, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Haniyeh Hemmatian
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Reena Desai
- ANZAC Research Institute, University of Sydney and Andrology, Concord Repatriation General Hospital, Concord, NSW, 2137, Australia
| | - David J Handelsman
- ANZAC Research Institute, University of Sydney and Andrology, Concord Repatriation General Hospital, Concord, NSW, 2137, Australia
| | - Jeffrey D Zajac
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Mathis Grossmann
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Rachel A Davey
- Department of Medicine, Austin Health, University of Melbourne, Heidelberg, VIC, 3084, Australia.
| |
Collapse
|
7
|
Venkatesh VS, Nie T, Zajac JD, Grossmann M, Davey RA. The Utility of Preclinical Models in Understanding the Bone Health of Transgender Individuals Undergoing Gender-Affirming Hormone Therapy. Curr Osteoporos Rep 2023; 21:825-841. [PMID: 37707757 PMCID: PMC10724092 DOI: 10.1007/s11914-023-00818-2] [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] [Accepted: 08/16/2023] [Indexed: 09/15/2023]
Abstract
PURPOSE OF REVIEW To summarise the evidence regarding the effects of gender-affirming hormone therapy (GAHT) on bone health in transgender people, to identify key knowledge gaps and how these gaps can be addressed using preclinical rodent models. RECENT FINDINGS Sex hormones play a critical role in bone physiology, yet there is a paucity of research regarding the effects of GAHT on bone microstructure and fracture risk in transgender individuals. The controlled clinical studies required to yield fracture data are unethical to conduct making clinically translatable preclinical research of the utmost importance. Novel genetic and surgical preclinical models have yielded significant mechanistic insight into the roles of sex steroids on skeletal integrity. Preclinical models of GAHT have the potential inform clinical approaches to preserve skeletal integrity and prevent fractures in transgender people undergoing GAHT. This review highlights the key considerations required to ensure the information gained from preclinical models of GAHT are informative.
Collapse
Affiliation(s)
- Varun S Venkatesh
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, 3084, Australia
| | - Tian Nie
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, 3084, Australia
| | - Jeffrey D Zajac
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, 3084, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, 3084, Australia
| | - Mathis Grossmann
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, 3084, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, 3084, Australia
| | - Rachel A Davey
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, Victoria, 3084, Australia.
| |
Collapse
|
8
|
Cheung AS. Reversible Effects of Puberty Suppression on Bone Strength, Mass, and Body Composition in Adolescent Mice After Testosterone Therapy. J Bone Miner Res 2023; 38:1389-1390. [PMID: 37701985 DOI: 10.1002/jbmr.4906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/06/2023] [Accepted: 08/13/2023] [Indexed: 09/14/2023]
Affiliation(s)
- Ada S Cheung
- Trans Health Research Group, The University of Melbourne, Heidelberg, Australia
- Department of Endocrinology, Austin Health, Heidelberg, Australia
| |
Collapse
|