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Babey ME, Krause WC, Chen K, Herber CB, Torok Z, Nikkanen J, Rodriguez R, Zhang X, Castro-Navarro F, Wang Y, Wheeler EE, Villeda S, Leach JK, Lane NE, Scheller EL, Chan CKF, Ambrosi TH, Ingraham HA. A maternal brain hormone that builds bone. Nature 2024; 632:357-365. [PMID: 38987585 PMCID: PMC11306098 DOI: 10.1038/s41586-024-07634-3] [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: 09/16/2023] [Accepted: 05/30/2024] [Indexed: 07/12/2024]
Abstract
In lactating mothers, the high calcium (Ca2+) demand for milk production triggers significant bone loss1. Although oestrogen normally counteracts excessive bone resorption by promoting bone formation, this sex steroid drops precipitously during this postpartum period. Here we report that brain-derived cellular communication network factor 3 (CCN3) secreted from KISS1 neurons of the arcuate nucleus (ARCKISS1) fills this void and functions as a potent osteoanabolic factor to build bone in lactating females. We began by showing that our previously reported female-specific, dense bone phenotype2 originates from a humoral factor that promotes bone mass and acts on skeletal stem cells to increase their frequency and osteochondrogenic potential. This circulatory factor was then identified as CCN3, a brain-derived hormone from ARCKISS1 neurons that is able to stimulate mouse and human skeletal stem cell activity, increase bone remodelling and accelerate fracture repair in young and old mice of both sexes. The role of CCN3 in normal female physiology was revealed after detecting a burst of CCN3 expression in ARCKISS1 neurons coincident with lactation. After reducing CCN3 in ARCKISS1 neurons, lactating mothers lost bone and failed to sustain their progeny when challenged with a low-calcium diet. Our findings establish CCN3 as a potentially new therapeutic osteoanabolic hormone for both sexes and define a new maternal brain hormone for ensuring species survival in mammals.
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Affiliation(s)
- Muriel E Babey
- Department of Medicine, Division of Endocrinology and Metabolism, University of California, San Francisco, San Francisco, CA, USA
| | - William C Krause
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Kun Chen
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, CA, USA
| | - Candice B Herber
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Denali Therapeutics, South San Francisco, CA, USA
| | - Zsofia Torok
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Joni Nikkanen
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, USA
| | - Ruben Rodriguez
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Carmot Therapeutics, Berkeley, CA, USA
| | - Xiao Zhang
- Department of Medicine, Washington University, St Louis, MO, USA
| | - Fernanda Castro-Navarro
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - Yuting Wang
- Institute for Stem Cell Biology and Regenerative Medicine and Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Erika E Wheeler
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, CA, USA
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
| | - Saul Villeda
- Department of Anatomy, University of California, San Francisco, San Francisco, CA, USA
| | - J Kent Leach
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, CA, USA
- Department of Biomedical Engineering, University of California, Davis, Davis, CA, USA
| | - Nancy E Lane
- Department of Medicine, Division of Rheumatology, University of California, Davis, Sacramento, CA, USA
| | - Erica L Scheller
- Department of Medicine, Washington University, St Louis, MO, USA
| | - Charles K F Chan
- Institute for Stem Cell Biology and Regenerative Medicine and Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Thomas H Ambrosi
- Department of Orthopaedic Surgery, University of California, Davis, Sacramento, CA, USA.
| | - Holly A Ingraham
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA.
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Dash AS, Billings E, Vlastaris K, Kim HJ, Cunningham ME, Raphael J, Lovecchio F, Carrino JA, Lebl D, McMahon D, Stein EM. Pre-operative bone quality deficits and risk of complications following spine fusion surgery among postmenopausal women. Osteoporos Int 2024; 35:551-560. [PMID: 37932510 DOI: 10.1007/s00198-023-06963-9] [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: 06/22/2023] [Accepted: 10/31/2023] [Indexed: 11/08/2023]
Abstract
Poor bone quality is a risk factor for complications after spinal fusion surgery. This study investigated pre-operative bone quality in postmenopausal women undergoing spine fusion and found that those with small bones, thinner cortices and surgeries involving more vertebral levels were at highest risk for complications. PURPOSE Spinal fusion is one of the most common surgeries performed worldwide. While skeletal complications are common, underlying skeletal deficits are often missed by pre-operative DXA due to artifact from spinal pathology. This prospective cohort study investigated pre-operative bone quality using high resolution peripheral CT (HRpQCT) and its relation to post-operative outcomes in postmenopausal women, a population that may be at particular risk for skeletal complications. We hypothesized that women with low volumetric BMD (vBMD) and abnormal microarchitecture would have higher rates of post-operative complications. METHODS Pre-operative imaging included areal BMD (aBMD) by DXA, cortical and trabecular vBMD and microarchitecture of the radius and tibia by high resolution peripheral CT. Intra-operative bone quality was subjectively graded based on resistance to pedicle screw insertion. Post-operative complications were assessed by radiographs and CTs. RESULTS Among 50 women enrolled (age 65 years), mean spine aBMD was normal and 35% had osteoporosis by DXA at any site. Low aBMD and vBMD were associated with "poor" subjective intra-operative quality. Skeletal complications occurred in 46% over a median follow-up of 15 months. In Cox proportional models, complications were associated with greater number of surgical levels (HR 1.19 95% CI 1.06-1.34), smaller tibia total area (HR 1.67 95% CI1.16-2.44) and lower tibial cortical thickness (HR 1.35 95% CI 1.05-1.75; model p < 0.01). CONCLUSION Women with smaller bones, thinner cortices and procedures involving a greater number of vertebrae were at highest risk for post-operative complications, providing insights into surgical and skeletal risk factors for complications in this population.
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Affiliation(s)
- Alexander S Dash
- Endocrinology and Metabolic Bone Disease Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
- Department of Medical Education, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Emma Billings
- Endocrinology and Metabolic Bone Disease Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
| | - Katelyn Vlastaris
- Endocrinology and Metabolic Bone Disease Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
| | - Han Jo Kim
- Spine Service, Hospital for Special Surgery, New York, NY, USA
| | | | - Joseph Raphael
- Endocrinology and Metabolic Bone Disease Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
| | | | - John A Carrino
- Department of Radiology, Hospital for Special Surgery, New York, NY, USA
| | - Darren Lebl
- Spine Service, Hospital for Special Surgery, New York, NY, USA
| | - Donald McMahon
- Endocrinology and Metabolic Bone Disease Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA
| | - Emily M Stein
- Endocrinology and Metabolic Bone Disease Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA.
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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.
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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.
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Babey ME, Krause WC, Herber CB, Chen K, Nikkanen J, Rodriquez R, Zhang X, Castro-Navarro F, Wang Y, Villeda S, Lane NE, Scheller EL, Chan CKF, Ambrosi TH, Ingraham HA. Brain-Derived CCN3 Is An Osteoanabolic Hormone That Sustains Bone in Lactating Females. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.28.554707. [PMID: 37693376 PMCID: PMC10491109 DOI: 10.1101/2023.08.28.554707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
In lactating mothers, the high calcium (Ca 2+ ) demand for milk production triggers significant bone resorption. While estrogen would normally counteract excessive bone loss and maintain sufficient bone formation during this postpartum period, this sex steroid drops precipitously after giving birth. Here, we report that brain-derived CCN3 (Cellular Communication Network factor 3) secreted from KISS1 neurons of the arcuate nucleus (ARC KISS1 ) fills this void and functions as a potent osteoanabolic factor to promote bone mass in lactating females. Using parabiosis and bone transplant methods, we first established that a humoral factor accounts for the female-specific, high bone mass previously observed by our group after deleting estrogen receptor alpha (ER α ) from ARC KISS1 neurons 1 . This exceptional bone phenotype in mutant females can be traced back to skeletal stem cells (SSCs), as reflected by their increased frequency and osteochondrogenic potential. Based on multiple assays, CCN3 emerged as the most promising secreted pro-osteogenic factor from ARC KISS1 neurons, acting on mouse and human SSCs at low subnanomolar concentrations independent of age or sex. That brain-derived CCN3 promotes bone formation was further confirmed by in vivo gain- and loss-of-function studies. Notably, a transient rise in CCN3 appears in ARC KISS1 neurons in estrogen-depleted lactating females coincident with increased bone remodeling and high calcium demand. Our findings establish CCN3 as a potentially new therapeutic osteoanabolic hormone that defines a novel female-specific brain-bone axis for ensuring mammalian species survival.
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Doolittle ML, Eckhardt BA, Vos SJ, Grain S, Rowsey JL, Ruan M, Saul D, Farr JN, Weivoda MM, Khosla S, Monroe DG. Modest Effects of Osteoclast-Specific ERα Deletion after Skeletal Maturity. JBMR Plus 2023; 7:e10797. [PMID: 37808391 PMCID: PMC10556268 DOI: 10.1002/jbm4.10797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/15/2023] [Accepted: 06/28/2023] [Indexed: 10/10/2023] Open
Abstract
Estrogen regulates bone mass in women and men, but the underlying cellular mechanisms of estrogen action on bone remain unclear. Although both estrogen receptor (ER)α and ERβ are expressed in bone cells, ERα is the dominant receptor for skeletal estrogen action. Previous studies using either global or cell-specific ERα deletion provided important insights, but each of these approaches had limitations. Specifically, either high circulating sex steroid levels in global ERα knockout mice or the effects of deletion of ERα during growth and development in constitutive cell-specific knockout mice have made it difficult to clearly define the role of ERα in specific cell types in the adult skeleton. We recently generated and characterized mice with tamoxifen-inducible ERα deletion in osteocytes driven by the 8-kb Dmp1 promoter (ERαΔOcy mice), revealing detrimental effects of osteocyte-specific ERα deletion on trabecular bone volume (-20.1%) and bone formation rate (-18.9%) in female, but not male, mice. Here, we developed and characterized analogous mice with inducible ERα deletion in osteoclasts using the Cathepsin K promoter (ERαΔOcl mice). In a study design identical to that with the previously described ERαΔOcy mice, adult female, but not male, ERαΔOcl mice showed a borderline (-10.2%, p = 0.084) reduction in trabecular bone volume, no change in osteoclast numbers, but a significant increase in serum CTx levels, consistent with increased osteoclast activity. These findings in ERαΔOcl mice differ from previous studies of constitutive osteoclast-specific ERα deletion, which led to clear deficits in trabecular bone and increased osteoclast numbers. Collectively, these data indicate that in adult mice, estrogen action in the osteocyte is likely more important than via the osteoclast and that ERα deletion in osteoclasts from conception onward has more dramatic skeletal effects than inducible osteoclastic ERα deletion in adult mice. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Madison L. Doolittle
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Brittany A. Eckhardt
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Stephanie J. Vos
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Sarah Grain
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Jennifer L. Rowsey
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Ming Ruan
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Dominik Saul
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
- Department of Trauma and Reconstructive SurgeryEberhard Karls University Tübingen, BG Trauma Center TübingenTübingenGermany
| | - Joshua N. Farr
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Megan M. Weivoda
- Robert and Arlene Kogod Center on Aging and Division of HematologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - Sundeep Khosla
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
| | - David G. Monroe
- Robert and Arlene Kogod Center on Aging and Division of EndocrinologyMayo Clinic College of MedicineRochesterMinnesotaUSA
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Jackova Z, Stepan JJ, Coufal S, Kostovcik M, Galanova N, Reiss Z, Pavelka K, Wenchich L, Hruskova H, Kverka M. Interindividual differences contribute to variation in microbiota composition more than hormonal status: A prospective study. Front Endocrinol (Lausanne) 2023; 14:1139056. [PMID: 37033235 PMCID: PMC10081494 DOI: 10.3389/fendo.2023.1139056] [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: 01/06/2023] [Accepted: 02/13/2023] [Indexed: 04/11/2023] Open
Abstract
AIMS Ovarian hormone deficiency is one of the main risk factors for osteoporosis and bone fractures in women, and these risks can be mitigated by menopausal hormone therapy. Recent evidence suggests that gut microbiota may link changes in estrogen levels and bone metabolism. This study was conducted to investigate the potential relationship between hormonal and bone changes induced by oophorectomy and subsequent hormonal therapy and shifts in gut microbiota composition. METHODS We collected 159 stool and blood samples in several intervals from 58 women, who underwent bilateral oophorectomy. Changes in fecal microbiota were assessed in paired samples collected from each woman before and after oophorectomy or the start of hormone therapy. Bacterial composition was determined by sequencing the 16S rRNA gene on Illumina MiSeq. Blood levels of estradiol, FSH, biomarkers of bone metabolism, and indices of low-grade inflammation were measured using laboratory analytical systems and commercial ELISA. Areal bone mineral density (BMD) of the lumbar spine, proximal femur, and femur neck was measured using dual-energy X-ray absorptiometry. RESULTS We found no significant changes in gut microbiota composition 6 months after oophorectomy, despite major changes in hormone levels, BMD, and bone metabolism. A small decrease in bacterial diversity was apparent 18 months after surgery in taxonomy-aware metrics. Hormonal therapy after oophorectomy prevented bone loss but only marginally affected gut microbiota. There were no significant differences in β-diversity related to hormonal status, although several microbes (e.g., Lactococcus lactis) followed estrogen levels. Body mass index (BMI) was the most significantly associated with microbiota variance. Microbiota was not a suitable predictive factor for the state of bone metabolism. CONCLUSIONS We conclude that neither the loss of estrogens due to oophorectomy nor their gain due to subsequent hormonal therapy is associated with a specific gut microbiota signature. Sources of variability in microbiota composition are more related to interindividual differences than hormonal status.
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Affiliation(s)
- Zuzana Jackova
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
| | - Jan J. Stepan
- Institute of Rheumatology, Prague, Czechia
- Department of Rheumatology, First Faculty of Medicine, Charles University in Prague, Prague, Czechia
| | - Stepan Coufal
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
| | - Martin Kostovcik
- Laboratory of Fungal Genetics and Metabolism, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
| | - Natalie Galanova
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
| | - Zuzana Reiss
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
| | - Karel Pavelka
- Institute of Rheumatology, Prague, Czechia
- Department of Rheumatology, First Faculty of Medicine, Charles University in Prague, Prague, Czechia
| | | | - Hana Hruskova
- Department of Obstetrics and Gynecology, Charles University in Prague, First Faculty of Medicine, Prague, Czechia
- General University Hospital in Prague, Prague, Czechia
| | - Miloslav Kverka
- Laboratory of Cellular and Molecular Immunology, Institute of Microbiology, Czech Academy of Sciences, Prague, Czechia
- *Correspondence: Miloslav Kverka,
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Artsi H, Cohen-Kfir E, Shahar R, Kalish-Achrai N, Lishinsky N, Dresner-Pollak R. SIRT1 haplo-insufficiency results in reduced cortical bone thickness, increased porosity and decreased estrogen receptor alpha in bone in adult 129/Sv female mice. Front Endocrinol (Lausanne) 2022; 13:1032262. [PMID: 36568088 PMCID: PMC9768543 DOI: 10.3389/fendo.2022.1032262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 11/15/2022] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Sirtuin 1 (SIRT1) is a key player in aging and metabolism and regulates bone mass and architecture. Sexual dimorphism in skeletal effects of SIRT1 has been reported, with an unfavorable phenotype primarily in female mice. METHODS To investigate the mechanisms of gender differences in SIRT1 skeletal effect, we investigated femoral and vertebral cortical and cancellous bone in global Sirt1 haplo-insufficient 129/Sv mice aged 2,7,12 months lacking Sirt1 exons 5,6,7 (Sirt1+/Δ ) and their wild type (WT) counterparts. RESULTS In females, femoral bone mineral content, peak cortical thickness, and trabecular bone volume (BV/TV%), number and thickness were significantly lower in Sirt1+/Δ compared to WT mice. Increased femoral cortical porosity was observed in 7-month-old Sirt1+/Δ compared to WT female mice, accompanied by reduced biomechanical strength. No difference in vertebral indices was detected between Sirt1+/Δ and WT female mice. SIRT1 decreased with aging in WT female mice and was lower in vertebrae and femur in 18- and 30- versus 3-month-old 129/Sv and C57BL/6J female mice, respectively. Decreased bone estrogen receptor alpha (ERα) was observed in Sirt1+/Δ compared to WT female mice and was significantly higher in Sirt1 over-expressing C3HT101/2 murine mesenchymal stem cells. In males no difference in femoral indices was detected in Sirt1+/Δ versus WT mice, however vertebral BV/TV%, trabecular number and thickness were higher in Sirt1+/Δ vs. WT mice. No difference in androgen receptor (AR) was detected in bone in Sirt1+/Δ vs. WT male mice. Bone SIRT1 was significantly lower in male compared to female WT mice, suggesting that SIRT1 maybe more significant in female than male skeleton. DISCUSSION These findings demonstrate that 50% reduction in SIRT1 is sufficient to induce the hallmarks of skeletal aging namely, decreased cortical thickness and increased porosity in female mice, highlighting the role of SIRT1 as a regulator of cortical bone quantity and quality. The effects of SIRT1 in cortical bone are likely mediated in part by its regulation of ERα. The age-associated decline in bone SIRT1 positions SIRT1 as a potential therapeutic target to ameliorate age-related cortical bone deterioration in females. The crosstalk between ERα, AR and SIRT1 in the bone microenvironment remains to be further investigated.
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Affiliation(s)
- Hanna Artsi
- Department of Endocrinology and Metabolism, Division of Medicine, Hadassah Medical Organization, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Einav Cohen-Kfir
- Department of Endocrinology and Metabolism, Division of Medicine, Hadassah Medical Organization, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ron Shahar
- Laboratory of Bone Biomechanics, Koret School of Veterinary Medicine, Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot, Israel
| | - Noga Kalish-Achrai
- Laboratory of Bone Biomechanics, Koret School of Veterinary Medicine, Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot, Israel
| | - Natan Lishinsky
- Department of Endocrinology and Metabolism, Division of Medicine, Hadassah Medical Organization, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Rivka Dresner-Pollak
- Department of Endocrinology and Metabolism, Division of Medicine, Hadassah Medical Organization, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- *Correspondence: Rivka Dresner-Pollak,
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