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Moon HH, Clines KL, O'Day PJ, Al-Barghouthi BM, Farber EA, Farber CR, Auchus RJ, Clines GA. Osteoblasts Generate Testosterone From DHEA and Activate Androgen Signaling in Prostate Cancer Cells. J Bone Miner Res 2021; 36:1566-1579. [PMID: 33900658 PMCID: PMC8565089 DOI: 10.1002/jbmr.4313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 04/13/2021] [Accepted: 04/17/2021] [Indexed: 01/25/2023]
Abstract
Bone metastasis is a complication of prostate cancer in up to 90% of men afflicted with advanced disease. Therapies that reduce androgen exposure remain at the forefront of treatment. However, most prostate cancers transition to a state whereby reducing testicular androgen action becomes ineffective. A common mechanism of this transition is intratumoral production of testosterone (T) using the adrenal androgen precursor dehydroepiandrosterone (DHEA) through enzymatic conversion by 3β- and 17β-hydroxysteroid dehydrogenases (3βHSD and 17βHSD). Given the ability of prostate cancer to form blastic metastases in bone, we hypothesized that osteoblasts might be a source of androgen synthesis. RNA expression analyses of murine osteoblasts and human bone confirmed that at least one 3βHSD and 17βHSD enzyme isoform was expressed, suggesting that osteoblasts are capable of generating androgens from adrenal DHEA. Murine osteoblasts were treated with 100 nM and 1 μM DHEA or vehicle control. Conditioned media from these osteoblasts were assayed for intermediate and active androgens by liquid chromatography-tandem mass spectrometry. As DHEA was consumed, the androgen intermediates androstenediol and androstenedione were generated and subsequently converted to T. Conditioned media of DHEA-treated osteoblasts increased androgen receptor (AR) signaling, prostate-specific antigen (PSA) production, and cell numbers of the androgen-sensitive prostate cancer cell lines C4-2B and LNCaP. DHEA did not induce AR signaling in osteoblasts despite AR expression in this cell type. We describe an unreported function of osteoblasts as a source of T that is especially relevant during androgen-responsive metastatic prostate cancer invasion into bone. © 2021 American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.
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Affiliation(s)
- Henry H Moon
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Ann Arbor, MI, USA
| | - Katrina L Clines
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Ann Arbor, MI, USA
| | - Patrick J O'Day
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Ann Arbor, MI, USA
| | | | - Emily A Farber
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA
| | - Charles R Farber
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA, USA.,Departments of Public Health Sciences, and Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, USA
| | - Richard J Auchus
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Ann Arbor, MI, USA.,Endocrinology & Metabolism Section, Medicine Service, Veterans Affairs Medical Center, Ann Arbor, MI, USA
| | - Gregory A Clines
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Ann Arbor, MI, USA.,Endocrinology & Metabolism Section, Medicine Service, Veterans Affairs Medical Center, Ann Arbor, MI, USA
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Heinosalo T, Saarinen N, Poutanen M. Role of hydroxysteroid (17beta) dehydrogenase type 1 in reproductive tissues and hormone-dependent diseases. Mol Cell Endocrinol 2019; 489:9-31. [PMID: 30149044 DOI: 10.1016/j.mce.2018.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 07/14/2018] [Accepted: 08/13/2018] [Indexed: 12/12/2022]
Abstract
Abnormal synthesis and metabolism of sex steroids is involved in the pathogenesis of various human diseases, such as endometriosis and cancers arising from the breast and uterus. Steroid biosynthesis is a multistep enzymatic process proceeding from cholesterol to highly active sex steroids via different intermediates. Human Hydroxysteroid (17beta) dehydrogenase 1 (HSD17B1) enzyme shows a high capacity to produce the highly active estrogen, estradiol, from a precursor hormone, estrone. However, the enzyme may also play a role in other steps of the steroid biosynthesis pathway. In this article, we have reviewed the literature on HSD17B1, and summarize the role of the enzyme in hormone-dependent diseases in women as evidenced by preclinical studies.
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Affiliation(s)
- Taija Heinosalo
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, Turku Center for Disease Modeling, University of Turku, Turku, Finland.
| | - Niina Saarinen
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, Turku Center for Disease Modeling, University of Turku, Turku, Finland
| | - Matti Poutanen
- Institute of Biomedicine, Research Centre for Integrative Physiology and Pharmacology, Turku Center for Disease Modeling, University of Turku, Turku, Finland; Institute of Medicine, The Sahlgrenska Academy, Gothenburg University, 413 45, Gothenburg, Sweden
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3
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Type 2 17-β hydroxysteroid dehydrogenase as a novel target for the treatment of osteoporosis. Future Med Chem 2016; 7:1431-56. [PMID: 26230882 DOI: 10.4155/fmc.15.74] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Low estradiol level in postmenopausal women is implicated in osteoporosis, which occurs because of the high bone resorption rate. Estrogen formation is controlled by 17-β hydroxysteroid dehydrogenase 17-β HSD enzymes, where 17-β HSD type 1 contributes in the formation of estradiol, while type 2 catalyzes its catabolism. Inhibiting 17-β HSD2 can help in increasing estradiol concentration. Several promising 17-β HSD2 inhibitors that can act at low nanomolar range have been identified. However, there are some specific challenges associated with the application of these compounds. Our review provides an up-to-date summary of the current status and recent progress in the production of 17-β HSD2 inhibitors as well as the future challenges in their clinical application.
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4
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Gargano EM, Perspicace E, Hanke N, Carotti A, Marchais-Oberwinkler S, Hartmann RW. Metabolic stability optimization and metabolite identification of 2,5-thiophene amide 17β-hydroxysteroid dehydrogenase type 2 inhibitors. Eur J Med Chem 2014; 87:203-19. [DOI: 10.1016/j.ejmech.2014.09.061] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 09/16/2014] [Accepted: 09/18/2014] [Indexed: 12/26/2022]
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5
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Dias NJ, Selcer KW. Steroid sulfatase mediated growth Sof human MG-63 pre-osteoblastic cells. Steroids 2014; 88:77-82. [PMID: 25042472 DOI: 10.1016/j.steroids.2014.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 07/01/2014] [Accepted: 07/07/2014] [Indexed: 01/18/2023]
Abstract
Estrogen plays an important role in maintaining bone density. Postmenopausal women have low plasma estrogen, but have high levels of conjugated steroids, particularly estrone sulfate (E1S) and dehydroepiandrosterone sulfate (DHEAS). Conversion of these precursors to active estrogens may help maintain bone density in postmenopausal women. The enzyme steroid sulfatase (STS) converts sulfated steroids into active forms in peripheral tissues. STS occurs in bone, but little is known about its role in bone function. In this study, we investigated STS activity and expression in the human MG-63 pre-osteoblastic cell line. We also tested whether sulfated steroids can stimulate growth of these cells. MG-63 cells and microsomes both possessed STS activity, which was blocked by the STS inhibitors EMATE and 667 Coumate. Further evidence for STS in these cells was provided by RT-PCR, using STS specific primers, which resulted in cDNA products of the predicted size. We then tested for growth of MG-63 cells in the presence of estradiol-17β, E1S and DHEAS. All three steroids stimulated MG-63 cell growth in a steroid-free basal medium. We also tested whether the cell growth induced by sulfated steroids could be blocked using a STS inhibitor (667 Coumate) or using an estrogen receptor blocker (ICI 182,780). Both compounds inhibited E1S-induced cell growth, indicating that E1S stimulates MG-63 cell growth through a mechanism involving both STS and the estrogen receptor. Finally, we demonstrated using RT-PCR that MG-63 cells contain mRNA for both estrogen receptor alpha and estrogen receptor beta. Our data reveal that STS is present in human pre-osteoblastic bone cells and that it can influence bone cell growth by converting inactive sulfated steroids to estrogenic forms that act via estrogen receptor alpha or beta.
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Affiliation(s)
- N J Dias
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA
| | - K W Selcer
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA.
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6
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Aceves-Ramos A, de la Torre P, Hinojosa L, Ponce A, García-Villegas R, Laclette JP, Bobes RJ, Romano MC. Cloning, characterization and functional expression of Taenia solium 17 beta-hydroxysteroid dehydrogenase. Gen Comp Endocrinol 2014; 203:186-92. [PMID: 24698785 DOI: 10.1016/j.ygcen.2014.03.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 03/07/2014] [Accepted: 03/13/2014] [Indexed: 12/24/2022]
Abstract
The 17β-hydroxysteroid dehydrogenases (17β-HSD) are key enzymes involved in the formation (reduction) and inactivation (oxidation) of sex steroids. Several types have been found in vertebrates including fish, as well as in invertebrates like Caenorhabditis elegans, Ciona intestinalis and Haliotis diversicolor supertexta. To date limited information is available about this enzyme in parasites. We showed previously that Taenia solium cysticerci are able to synthesize sex steroid hormones in vitro when precursors are provided in the culture medium. Here, we identified a T. solium 17β-HSD through in silico blast searches in the T. solium genome database. This coding sequence was amplified by RT-PCR and cloned into the pcDNA 3.1(+) expression vector. The full length cDNA contains 957bp, corresponding to an open reading frame coding for 319 aa. The highest identity (84%) at the protein level was found with the Echinococcus multilocularis 17β-HSD although significant similarities were also found with other invertebrate and vertebrate 17β-HSD sequences. The T. solium Tsol-17βHSD belongs to the short-chain dehydrogenase/reductase (SDR) protein superfamily. HEK293T cells transiently transfected with Tsol17β-HSD induced expression of Tsol17β-HSD that transformed 3H-androstenedione into testosterone. In contrast, 3H-estrone was not significantly transformed into estradiol. In conclusion, T. solium cysticerci express a 17β-HSD that catalyzes the androgen reduction. The enzyme belongs to the short chain dehydrogenases/reductase family and shares motifs and activity with the type 3 enzyme of some other species.
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Affiliation(s)
- A Aceves-Ramos
- Dpto. de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-740, 07000 México, D.F., Mexico
| | - P de la Torre
- Dpto. de Inmunología, Instituto de Investigaciones Biomédicas, UNAM, México, D.F., Mexico
| | - L Hinojosa
- Dpto. de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-740, 07000 México, D.F., Mexico
| | - A Ponce
- Dpto. de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-740, 07000 México, D.F., Mexico
| | - R García-Villegas
- Dpto. de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-740, 07000 México, D.F., Mexico
| | - J P Laclette
- Dpto. de Inmunología, Instituto de Investigaciones Biomédicas, UNAM, México, D.F., Mexico
| | - R J Bobes
- Dpto. de Inmunología, Instituto de Investigaciones Biomédicas, UNAM, México, D.F., Mexico
| | - M C Romano
- Dpto. de Fisiología, Biofísica y Neurociencias, CINVESTAV del I.P.N., Apdo. Postal 14-740, 07000 México, D.F., Mexico.
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7
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Marchais-Oberwinkler S, Xu K, Wetzel M, Perspicace E, Negri M, Meyer A, Odermatt A, Möller G, Adamski J, Hartmann RW. Structural Optimization of 2,5-Thiophene Amides as Highly Potent and Selective 17β-Hydroxysteroid Dehydrogenase Type 2 Inhibitors for the Treatment of Osteoporosis. J Med Chem 2012; 56:167-81. [DOI: 10.1021/jm3014053] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
| | - Kuiying Xu
- Pharmaceutical and Medicinal
Chemistry, Saarland University, D-66041
Saarbrücken, Germany
| | - Marie Wetzel
- Pharmaceutical and Medicinal
Chemistry, Saarland University, D-66041
Saarbrücken, Germany
| | - Enrico Perspicace
- Pharmaceutical and Medicinal
Chemistry, Saarland University, D-66041
Saarbrücken, Germany
| | - Matthias Negri
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Campus
C23, D-66123 Saarbrücken, Germany
| | - Arne Meyer
- Division of Molecular and Systems
Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstraße 50, CH-4056 Basel,
Switzerland
| | - Alex Odermatt
- Division of Molecular and Systems
Toxicology, Department of Pharmaceutical Sciences, University of Basel, Klingelbergstraße 50, CH-4056 Basel,
Switzerland
| | - Gabriele Möller
- Genome Analysis
Center, Institute
of Experimental Genetic, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
| | - Jerzy Adamski
- Genome Analysis
Center, Institute
of Experimental Genetic, Helmholtz Zentrum München, D-85764 Neuherberg, Germany
- Lehrstuhl für Experimentelle
Genetik, Technische Universität München, D-85350 Freising-Weihenstephan, Germany
| | - Rolf W. Hartmann
- Pharmaceutical and Medicinal
Chemistry, Saarland University, D-66041
Saarbrücken, Germany
- Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Campus
C23, D-66123 Saarbrücken, Germany
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8
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Rotinen M, Villar J, Encío I. Regulation of 17β-hydroxysteroid dehydrogenases in cancer: regulating steroid receptor at pre-receptor stage. J Physiol Biochem 2012; 68:461-73. [DOI: 10.1007/s13105-012-0155-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 02/07/2012] [Indexed: 11/27/2022]
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9
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Svoboda M, Hamilton G, Thalhammer T. Steroid hormone metabolizing enzymes in benign and malignant human bone tumors. Expert Opin Drug Metab Toxicol 2010; 6:427-37. [PMID: 20102288 DOI: 10.1517/17425251003592129] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
UNLABELLED IMPORTANCE IN THE FIELD: Primary bone tumors are considered as (sex steroid) hormone-dependent tumors. Osteosarcoma, osteoblastoma and bone cysts are preferentially found in males, while giant cell tumors are more common in females. Indeed, bone tumor development and progression are influenced by sex steroid hormones derived from in situ synthesis in bone cells. AREAS COVERED IN THIS REVIEW This review describes intracrine mechanisms for local formation of the biologically most active estrogen, 17beta-estradiol (E2), from circulating steroid precursors through the 'aromatase' (aromatization of androgens) and the 'sulfatase' (conversion of inactive estrone-sulfate) pathway. WHAT THE READER WILL GAIN The reader gains knowledge on both pathways and the enzymes, which contribute to the in situ availability of active hormones, namely 3beta-hydroxysteroid dehydrogenases, 17beta-hydroxysteroid dehydrogenases, aromatase, steroid sulfatases and sulfotransferases. An overview is given and the expression and function of these enzymes in bone tumors are discussed. TAKE HOME MESSAGE Knowledge on pathways for the in situ formation of E2 in bone cells may allow the identification of potential targets for i) novel endocrine therapeutic options in primary bone tumors and ii) future preventive interventions.
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Affiliation(s)
- Martin Svoboda
- Department of Pathophysiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090, Vienna, Austria
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10
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Jankowski CM, Gozansky WS, Kittelson JM, Van Pelt RE, Schwartz RS, Kohrt WM. Increases in bone mineral density in response to oral dehydroepiandrosterone replacement in older adults appear to be mediated by serum estrogens. J Clin Endocrinol Metab 2008; 93:4767-73. [PMID: 18812486 PMCID: PMC2626446 DOI: 10.1210/jc.2007-2614] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT The mechanisms by which dehydroepiandrosterone (DHEA) replacement increases bone mineral density (BMD) in older adults are not known. OBJECTIVE The aims were to determine the effects of DHEA therapy on changes in sex hormones and IGF-I and their associations with changes in BMD. DESIGN, SETTING, AND PARTICIPANTS A randomized, double-blinded, placebo-controlled trial was conducted at an academic research institution. Participants were 58 women and 61 men, aged 60-88 yr, with low serum DHEA sulfate (DHEAS) levels. INTERVENTION The intervention was oral DHEA 50 mg/d or placebo for 12 months. MAIN OUTCOME MEASURES BMD and serum DHEAS, testosterone, estradiol (E(2)), estrone (E(1)), SHBG, IGF-I, and IGF binding protein 3 were measured before and after intervention. Free testosterone and estrogen (FEI) indices were calculated. RESULTS The average changes in hip and spine BMD (DHEA vs. placebo) ranged from 1.1 to 1.6%. Compared with placebo, DHEA replacement increased serum DHEAS, testosterone, free testosterone index, E(1), E(2), FEI, and IGF-I (all P < 0.001) and decreased SHBG (P = 0.02) in women and, in men, increased DHEAS, E(1), FEI (all P < 0.001), and E(2) (P = 0.02) and decreased SHBG (P = 0.037). The changes in total and regional hip BMD were associated with 12-month E(2) (all P <or= 0.001) and FEI (all P <or= 0.013). The effects of DHEA treatment were eliminated by adjustment for 12-month E(2). CONCLUSIONS The significant increases in hip BMD in older adults undergoing DHEA replacement were mediated primarily by increases in serum E(2) rather than direct effects of DHEAS.
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Affiliation(s)
- Catherine M Jankowski
- Division of Geriatric Medicine, University of Colorado Denver, mail stop B179, Room 8111, 12631 East 17th Avenue, Aurora, Colorado 80045, USA
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11
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Eriksson AL, Mellström D, Lorentzon M, Orwoll ES, Redlund-Johnell I, Grundberg E, Holmberg A, Ljunggren O, Karlsson MK, Ohlsson C. The COMT val158met polymorphism is associated with prevalent fractures in Swedish men. Bone 2008; 42:107-12. [PMID: 17962094 DOI: 10.1016/j.bone.2007.08.045] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 06/01/2007] [Accepted: 08/27/2007] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Sex steroids are important for growth and maintenance of the skeleton. Catechol-O-methyltransferase (COMT) is an estrogen degrading enzyme. The COMT val158met polymorphism results in a 60-75% difference in enzyme activity between the val (high activity=H) and met (low activity=L) variants. We have previously reported that this polymorphism is associated with bone mineral density (BMD) in young men. The aim of this study was to investigate associations between COMT val158met, BMD and fractures in elderly men. METHODS Population-based study of Swedish men 75.4, SD 3.2, years of age. Fractures were reported using standardized questionnaires. Fracture and genotype data were available from 2,822 individuals. RESULTS Total number of individuals with self-reported fracture was 989 (35.0%). Prevalence of >or=1 fracture was 37.2% in COMT(LL), 35.7% in COMT(HL) and 30.4% in COMT(HH) (p<0.05). Early fractures (<or=50 years of age) were less common in COMT(HH) than in the combined COMT(LL+HL) genotype, OR 0.78 (95% CI 0.63-0.97). No associations were found for late fractures (>50 years of age). The OR for fracture of the non-weight bearing skeleton in COMT(HH) compared with COMT(LL+HL) was 0.74 (95% CI 0.59-0.92). No associations between COMT val158met and BMD were found in this cohort of elderly men. CONCLUSIONS The COMT val158met polymorphism is associated with life time fracture prevalence in elderly Swedish men. This association is mainly driven by early fractures (<or=50 years of age).
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Affiliation(s)
- Anna L Eriksson
- Center for Bone Research at the Sahlgrenska Academy, Departments of Internal Medicine and Geriatrics, The Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
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12
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Abstract
Loss of estrogens or androgens increases the rate of bone remodeling by removing restraining effects on osteoblastogenesis and osteoclastogenesis, and also causes a focal imbalance between resorption and formation by prolonging the lifespan of osteoclasts and shortening the lifespan of osteoblasts. Conversely, androgens, as well as estrogens, maintain cancellous bone mass and integrity, regardless of age or sex. Although androgens, via the androgen receptor (AR), and estrogens, via the estrogen receptors (ERs), can exert these effects, their relative contribution remains uncertain. Recent studies suggest that androgen action on cancellous bone depends on (local) aromatization of androgens into estrogens. However, at least in rodents, androgen action on cancellous bone can be directly mediated via AR activation, even in the absence of ERs. Androgens also increase cortical bone size via stimulation of both longitudinal and radial growth. First, androgens, like estrogens, have a biphasic effect on endochondral bone formation: at the start of puberty, sex steroids stimulate endochondral bone formation, whereas they induce epiphyseal closure at the end of puberty. Androgen action on the growth plate is, however, clearly mediated via aromatization in estrogens and interaction with ERalpha. Androgens increase radial growth, whereas estrogens decrease periosteal bone formation. This effect of androgens may be important because bone strength in males seems to be determined by relatively higher periosteal bone formation and, therefore, greater bone dimensions, relative to muscle mass at older age. Experiments in mice again suggest that both the AR and ERalpha pathways are involved in androgen action on radial bone growth. ERbeta may mediate growth-limiting effects of estrogens in the female but does not seem to be involved in the regulation of bone size in males. In conclusion, androgens may protect men against osteoporosis via maintenance of cancellous bone mass and expansion of cortical bone. Such androgen action on bone is mediated by the AR and ERalpha.
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Affiliation(s)
- Dirk Vanderschueren
- Laboratory for Experimental Medicine and Endocrinology, Katholieke Universiteit Leuven, Leuven, Belgium
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13
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Mindnich R, Möller G, Adamski J. The role of 17 beta-hydroxysteroid dehydrogenases. Mol Cell Endocrinol 2004; 218:7-20. [PMID: 15130507 DOI: 10.1016/j.mce.2003.12.006] [Citation(s) in RCA: 254] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2003] [Revised: 12/09/2003] [Accepted: 12/15/2003] [Indexed: 11/17/2022]
Abstract
The biological activity of steroid hormones is regulated at the pre-receptor level by several enzymes including 17 beta-hydroxysteroid dehydrogenases (17 beta -HSD). The latter are present in many microorganisms, invertebrates and vertebrates. Dysfunctions in human 17 beta-hydroxysteroid dehydrogenases result in disorders of biology of reproduction and neuronal diseases, the enzymes are also involved in the pathogenesis of various cancers. 17 beta-hydroxysteroid dehydrogenases reveal a remarkable multifunctionality being able to modulate concentrations not only of steroids but as well of fatty and bile acids. Current knowledge on genetics, biochemistry and medical implications is presented in this review.
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Affiliation(s)
- R Mindnich
- GSF-National Research Center for Environment and Health, Institute of Experimental Genetics, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
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14
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Abstract
The growth plate is the final target organ for longitudinal growth and results from chondrocyte proliferation and differentiation. During the first year of life, longitudinal growth rates are high, followed by a decade of modest longitudinal growth. The age at onset of puberty and the growth rate during the pubertal growth spurt (which occurs under the influence of estrogens and GH) contribute to sex difference in final height between boys and girls. At the end of puberty, growth plates fuse, thereby ceasing longitudinal growth. It has been recognized that receptors for many hormones such as estrogen, GH, and glucocorticoids are present in or on growth plate chondrocytes, suggesting that these hormones may influence processes in the growth plate directly. Moreover, many growth factors, i.e., IGF-I, Indian hedgehog, PTHrP, fibroblast growth factors, bone morphogenetic proteins, and vascular endothelial growth factor, are now considered as crucial regulators of chondrocyte proliferation and differentiation. In this review, we present an update on the present perception of growth plate function and the regulation of chondrocyte proliferation and differentiation by systemic and local regulators of which most are now related to human growth disorders.
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Affiliation(s)
- B C J van der Eerden
- Department of Pediatrics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
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15
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Affiliation(s)
- Willem de Ronde
- Department of Internal Medicine, University Hospital Dijkzigt, Rotterdam, The Netherlands.
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