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Gutierrez E, Mitchell S, Hambly C, Sayle KL, von Kriegsheim A, Speakman JR, Britton K. Carbon, nitrogen, and sulfur elemental and isotopic variations in mouse hair and bone collagen during short-term graded calorie restriction. iScience 2024; 27:110059. [PMID: 38947513 PMCID: PMC11214416 DOI: 10.1016/j.isci.2024.110059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 03/19/2024] [Accepted: 05/17/2024] [Indexed: 07/02/2024] Open
Abstract
This study characterized the effect of calorie restriction (CR) on elemental content and stable isotope ratio measurements of bone "collagen" and hair keratin. Adult mice on graded CR (10-40%; 84 days) showed decreased hair δ 15N, δ 13C, and δ 34S values (significantly for δ 15N) with increasing CR, alongside a significant increase in bone "collagen" δ 15N values and a decrease in "collagen" δ 13C values. We propose this was likely due to the intensified mobilization of endogenous proteins, as well as lipids in newly synthesized "collagen". Elemental analysis of bone "collagen" revealed decreased carbon, nitrogen, and sulfur % content with increasing CR which is attributed to a change in the in vivo bone "collagen" structure with extent of CR. This complexity challenges the use of elemental indicators in the assessment of collagen quality in archaeological studies where nutritional stress may be a factor.
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Affiliation(s)
- Eléa Gutierrez
- Department of Archaeology, University of Aberdeen, Aberdeen, Scotland AB39 2PN, UK
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland AB24 2TZ, UK
- AASPE “Archéozoologie, Archéobotanique: Sociétés, Pratiques, Environnements”, Muséum national d’Histoire naturelle, 75005 Paris, France
| | - Sharon Mitchell
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland AB24 2TZ, UK
| | - Catherine Hambly
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland AB24 2TZ, UK
| | - Kerry L. Sayle
- Scottish Universities Environmental Research Centre, University of Glasgow, Scotland G75 0QF, UK
| | - Alex von Kriegsheim
- Edinburgh Cancer Research UK Centre, MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh Scotland EH4 2XR, UK
| | - John R. Speakman
- School of Biological Sciences, University of Aberdeen, Aberdeen, Scotland AB24 2TZ, UK
- Shenzhen Key Laboratory of Metabolic Health, Centre for Energy Metabolism and Reproduction, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, PRC
- Centre of Excellence in Animal Evolution and Genetics, Kunming, PRC
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, PRC
| | - Kate Britton
- Department of Archaeology, University of Aberdeen, Aberdeen, Scotland AB39 2PN, UK
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Lv X, Gao F, Cao X. Skeletal interoception in bone homeostasis and pain. Cell Metab 2022; 34:1914-1931. [PMID: 36257317 PMCID: PMC9742337 DOI: 10.1016/j.cmet.2022.09.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 09/07/2022] [Accepted: 09/26/2022] [Indexed: 01/24/2023]
Abstract
Accumulating evidence indicates that interoception maintains proper physiological status and orchestrates metabolic homeostasis by regulating feeding behaviors, glucose balance, and lipid metabolism. Continuous skeletal remodeling consumes a tremendous amount of energy to provide skeletal scaffolding, support muscle movement, store vital minerals, and maintain a niche for hematopoiesis, which are processes that also contribute to overall metabolic balance. Although skeletal innervation has been described for centuries, recent work has shown that skeletal metabolism is tightly regulated by the nervous system and that skeletal interoception regulates bone homeostasis. Here, we provide a general discussion of interoception and its effects on the skeleton and whole-body metabolism. We also discuss skeletal interoception-mediated regulation in the context of pathological conditions and skeletal pain as well as future challenges to our understanding of these process and how they can be leveraged for more effective therapy.
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Affiliation(s)
- Xiao Lv
- Center for Musculoskeletal Research, Department of Orthopaedic Surgery and Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21205, USA
| | - Feng Gao
- Center for Musculoskeletal Research, Department of Orthopaedic Surgery and Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21205, USA
| | - Xu Cao
- Center for Musculoskeletal Research, Department of Orthopaedic Surgery and Department of Biomedical Engineering, The Johns Hopkins University, Baltimore, MD 21205, USA.
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Biosynthesis of Bonelike Apatite 2D Nanoplate Structures Using Fenugreek Seed Extract. NANOMATERIALS 2020; 10:nano10050919. [PMID: 32397480 PMCID: PMC7279542 DOI: 10.3390/nano10050919] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 04/29/2020] [Accepted: 05/03/2020] [Indexed: 12/12/2022]
Abstract
An innovative, biomimetic, green synthesis approach was exploited for the synthesis of humane and environmental friendly nanomaterials for biomedical applications. Ultrafine bonelike apatite (BAp) 2D plate-like structures were prepared using fenugreek seed extract during the biosynthesis wet-chemical precipitation route. The chemical analysis, morphology and structure of the prepared 2D nanoplates were characterized by inductively coupled plasma atomic emission spectroscopy (ICP-OES), electron microscopy (SEM and TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. A 2D plate-like nanostructure of BAp with an average width (length) of 12.67 ± 2 nm and thickness of 3.8 ± 1.2 nm was obtained. BAp 2D crystals were tuned by interaction with the fenugreek organic molecules during the fabrication process. In addition to Ca and P ions, bone mineral sources such as K, Mg, Na, SO4 and CO3 ions were incorporated into BAp nanoplates using fenugreek seed extract. The overall organic molecule concentration in the reaction process increased the effectiveness of hydroxyl groups as nucleation sites for BAp crystals. Accordingly, the size of the biosynthesized BAp plate-like structure was reduced to its lowest value. Biosynthesis BAp 2D plate-like nanocrystals showed good viability and higher growth of MC3T3 osteoblast-like structures than that of the control sample. BAp 2D nanoplates prepared by a facile, ecofriendly and cost-effective approach could be considered a favorable osteoconductive inorganic biomaterial for bone regeneration applications.
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Karsenty G. The Central Regulation of Bone Mass: Genetic Evidence and Molecular Bases. Handb Exp Pharmacol 2020; 262:309-323. [PMID: 32960342 DOI: 10.1007/164_2020_378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The alternation of resorption of preexisting bone by the osteoclasts followed by de novo bone formation by osteoblasts is called bone modeling during childhood and bone remodeling during adulthood. A central question raised by this physiological process that is fundamental to longitudinal growth during childhood and adolescence and that is attacked at the other end of life in the context of osteoporosis is to know how it is regulated. This question was rejuvenated in the late 1990s and early 2000s years when the application of mouse genetics made it feasible to test whether there were new endocrine determinants of bone (re)modeling. Addressing this question, taking into account fundamental cell biology features of bone led to the hypothesis that there should be a coordinated control of bone growth/mass, energy metabolism, and reproduction. Testing genetically and molecularly, this hypothesis revealed that, in vivo, the adipocyte-derived hormone leptin is a powerful inhibitor of bone mass accrual following its signaling in the brain. This chapter details the molecular bases and biological relevance of this regulation of bone mass accrual by leptin.
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Affiliation(s)
- Gerard Karsenty
- Departments of Genetics and Development, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA.
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5
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L'Huillier C, Jarbeau M, Achamrah N, Belmonte L, Amamou A, Nobis S, Goichon A, Salameh E, Bahlouli W, do Rego JL, Déchelotte P, Coëffier M. Glutamine, but not Branched-Chain Amino Acids, Restores Intestinal Barrier Function during Activity-Based Anorexia. Nutrients 2019; 11:nu11061348. [PMID: 31208031 PMCID: PMC6628073 DOI: 10.3390/nu11061348] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/11/2019] [Accepted: 06/13/2019] [Indexed: 12/21/2022] Open
Abstract
Background: During activity-based anorexia (ABA) in mice, enhanced paracellular permeability and reduced protein synthesis have been shown in the colon while the gut–brain axis has received increasing attention in the regulation of intestinal and mood disorders that frequently occur during anorexia nervosa, a severe eating disorder for which there is no specific treatment. In the present study, we assessed the effects of oral glutamine (Gln) or branched-chain amino acids (BCAA) supplementation during ABA to target intestinal functions, body composition and feeding behavior. Methods: C57BL/6 male mice were randomized in Control (CTRL) and ABA groups. After ABA induction, mice received, or not, either 1% Gln or 2.5% BCAA (Leu, Ile, Val) for one week in drinking water. Results: Neither Gln nor BCAA supplementation affected body weight and body composition, while only Gln supplementation slightly increased food intake. ABA mice exhibited increased paracellular permeability and reduced protein synthesis in the colonic mucosa. Oral Gln restored colonic paracellular permeability and protein synthesis and increased the mucin-2 mRNA level, whereas BCAA did not affect colonic parameters. Conclusion: In conclusion, oral Gln specifically improves colonic response during ABA. These data should be further confirmed in AN patients.
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Affiliation(s)
- Clément L'Huillier
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Marine Jarbeau
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Najate Achamrah
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
- Department of Nutrition, Rouen University Hospital, 76183 Rouen, France.
| | - Liliana Belmonte
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
- Department of Nutrition, Rouen University Hospital, 76183 Rouen, France.
| | - Asma Amamou
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Séverine Nobis
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Alexis Goichon
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Emmeline Salameh
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Wafa Bahlouli
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
| | - Jean-Luc do Rego
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
- Animal Behavior Facility, SCAC, UNIROUEN, 76183 Rouen, France.
| | - Pierre Déchelotte
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
- Department of Nutrition, Rouen University Hospital, 76183 Rouen, France.
| | - Moïse Coëffier
- UNIROUEN, INSERM UMR 1073 "Nutrition, Inflammation and Gut-Brain Axis", Normandie University, 76183 Rouen, France.
- Institute of Research and Innovation in Biomedicine (IRIB), UNIROUEN, Normandie University, 76183 Rouen, France.
- Department of Nutrition, Rouen University Hospital, 76183 Rouen, France.
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Abstract
Exercise is an evolutionary conserved survival function that nowadays has beneficial health effects. The increased metabolic activity of contracting skeletal muscle affects the biology of many organs involved in regulating muscle functions. The discovery of hormones and cytokines secreted by bone and skeletal muscle during exercise, has recently added experimental credence to the notion that a crosstalk exists between these organs. Bone through the hormone osteocalcin, promotes exercise capacity in the mouse. After binding to a G-coupled protein receptor, Gprc6a, osteocalcin increases nutrients uptake and catabolism in myofibers during exercise. The catabolic aspect of osteocalcin distinguishes it from insulin signaling. In addition, osteocalcin regulates the endocrine function of skeletal muscle because it enhances the expression of interleukin-6 (IL-6). IL-6 is produced and secreted by contracting skeletal muscle and exerts autocrine, paracrine and systemic effects. One of the systemic functions of IL-6 is to drive the generation of bioactive osteocalcin. Altogether, these studies have revealed a feed-forward loop between bone and skeletal muscle that are necessary and sufficient for optimum exercise capacity. This endocrine regulation of exercise biology, suggest novel and adapted strategies for the prevention or treatment of age related muscle loss.
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Affiliation(s)
- Gerard Karsenty
- Department of Genetics & Development, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
| | - Paula Mera
- Department of Genetics & Development, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
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Mera P, Ferron M, Mosialou I. Regulation of Energy Metabolism by Bone-Derived Hormones. Cold Spring Harb Perspect Med 2018; 8:cshperspect.a031666. [PMID: 28778968 DOI: 10.1101/cshperspect.a031666] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Like many other organs, bone can act as an endocrine organ through the secretion of bone-specific hormones or "osteokines." At least two osteokines are implicated in the control of glucose and energy metabolism: osteocalcin (OCN) and lipocalin-2 (LCN2). OCN stimulates the production and secretion of insulin by the pancreatic β-cells, but also favors adaptation to exercise by stimulating glucose and fatty acid (FA) utilization by the muscle. Both of these OCN functions are mediated by the G-protein-coupled receptor GPRC6A. In contrast, LCN2 influences energy metabolism by activating appetite-suppressing signaling in the brain. This action of LCN2 occurs through its binding to the melanocortin 4 receptor (MC4R) in the paraventricular nucleus of the hypothalamus (PVN) and ventromedial neurons of the hypothalamus.
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Affiliation(s)
- Paula Mera
- Columbia University Medical Center, New York, New York 10032
| | - Mathieu Ferron
- Institut de Recherches Cliniques de Montréal, Montréal, Quebec H2W 1R7, Canada
| | - Ioanna Mosialou
- Columbia University Medical Center, New York, New York 10032
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8
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Viltart O, Duriez P, Tolle V. Metabolic and neuroendocrine adaptations to undernutrition in anorexia nervosa: from a clinical to a basic research point of view. Horm Mol Biol Clin Investig 2018; 36:hmbci-2018-0010. [PMID: 29804101 DOI: 10.1515/hmbci-2018-0010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 03/13/2018] [Indexed: 02/07/2023]
Abstract
The exact mechanisms linking metabolic and neuroendocrine adaptations to undernutrition and the pathophysiology of anorexia nervosa (AN) are not fully understood. AN is a psychiatric disorder of complex etiology characterized by extreme starvation while the disease is progressing into a chronic state. Metabolic and endocrine alterations associated to this disorder are part of a powerful response to maintain whole body energy homeostasis. But these modifications may also contribute to associated neuropsychiatric symptoms (reward abnormalities, anxiety, depression) and thus participate to sustain the disease. The current review presents data with both a clinical and basic research point of view on the role of nutritional and energy sensors with neuroendocrine actions in the pathophysiology of the disease, as they modulate metabolic responses, reproductive functions, stress responses as well as physical activity. While clinical data present a full description of changes occurring in AN, animal models that integrate either spontaneous genetic mutations or experimentally-induced food restriction with hyperactivity and/or social stress recapitulate the main metabolic and endocrine alterations of AN and provide mechanistic information between undernutrition state and symptoms of the disease. Further progress on the central and peripheral mechanism involved in the pathophysiology of eating disorders partly relies on the development and/or refinement of existing animal models to include recently identified genetic traits and better mimic the complex and multifactorial dimensions of the disease.
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Affiliation(s)
- Odile Viltart
- Centre de Psychiatrie et Neurosciences, INSERM UMR 894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Université de Lille (Sciences et technologies), Lille, France
| | - Philibert Duriez
- Centre de Psychiatrie et Neurosciences, INSERM UMR 894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Clinique des Maladies Mentales et de l'Encéphale (CMME), Hôpital Sainte-Anne, Paris, France
| | - Virginie Tolle
- Centre de Psychiatrie et Neurosciences, INSERM UMR 894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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Tangseefa P, Martin SK, Fitter S, Baldock PA, Proud CG, Zannettino ACW. Osteocalcin-dependent regulation of glucose metabolism and fertility: Skeletal implications for the development of insulin resistance. J Cell Physiol 2017; 233:3769-3783. [PMID: 28834550 DOI: 10.1002/jcp.26163] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 08/22/2017] [Indexed: 01/22/2023]
Abstract
The skeleton has recently emerged as a critical insulin target tissue that regulates whole body glucose metabolism and male reproductive function. While our understanding of these new regulatory axes remains in its infancy, the bone-specific protein, osteocalcin, has been shown to be centrally involved. Undercarboxylated osteocalcin acts as a secretagogue in a feed-forward loop to stimulate pancreatic β-cell proliferation and insulin secretion, improve insulin sensitivity, and promote testosterone production. Importantly, dysregulation of insulin signaling in bone causes a reduction in serum osteocalcin levels that is associated with elevated blood glucose and reduced serum insulin levels, suggesting that the skeleton may play a significant role in the development of diet-induced insulin resistance. Insulin signaling is negatively regulated by the mammalian target of rapamycin complex 1 (mTORC1) which becomes hyper-activated in response to nutrient overload. Loss- and gain-of function models suggest that mTORC1 function in bone is essential for normal skeletal development; however, the role of this complex in the regulation of glucose metabolism remains to be determined. This review highlights our current understanding of the role played by osteocalcin in the skeletal regulation of glucose metabolism and fertility. In particular, it examines data emerging from transgenic mouse models which have revealed a pancreas-bone-testis regulatory axis and discusses recent human studies which seek to corroborate findings from mouse models with clinical observations. Moreover, we review recent studies which suggest dysregulation of insulin signaling in bone leads to the development of insulin resistance and discuss the potential role of mTORC1 signaling in this process.
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Affiliation(s)
- Pawanrat Tangseefa
- Faculty of Health and Medical Science, Myeloma Research Laboratory, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- Cancer Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Sally K Martin
- Faculty of Health and Medical Science, Myeloma Research Laboratory, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- Cancer Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Stephen Fitter
- Faculty of Health and Medical Science, Myeloma Research Laboratory, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- Cancer Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Paul A Baldock
- Skeletal Metabolism Group, Garvan Institute of Medical Research, Sydney, New South Wales, Australia
| | - Christopher G Proud
- Nutrition & Metabolism, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- School of Biological Sciences, University of Adelaide, Adelaide, South Australia, Australia
- Department of Biochemistry and Genetics, School of Medicine, Zhejiang University, Hangzhou, China
| | - Andrew C W Zannettino
- Faculty of Health and Medical Science, Myeloma Research Laboratory, Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
- Cancer Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
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10
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Robinson L, Aldridge V, Clark EM, Misra M, Micali N. Pharmacological treatment options for low Bone Mineral Density and secondary osteoporosis in Anorexia Nervosa: A systematic review of the literature. J Psychosom Res 2017; 98:87-97. [PMID: 28554377 PMCID: PMC7050204 DOI: 10.1016/j.jpsychores.2017.05.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 05/10/2017] [Accepted: 05/11/2017] [Indexed: 01/22/2023]
Abstract
OBJECTIVE Although there are several evidence-based treatments available to increase Bone Mineral Density (BMD) and reduce fracture risk in aging men and women, there are still uncertainties regarding which treatments are efficacious in reducing lifetime fracture risk in women with Anorexia Nervosa (AN). METHODS Medline, PsychInfo, Embase and the Cochrane Database were searched for English Language Studies. Inclusion criteria were studies of females of any age with AN who received pharmacological treatment with the primary aim to increase BMD or reduce fracture risk. Data were extracted from each study regarding pharmacological treatment and dosage used, BMD and bone formation marker outcomes; and participant characteristics including age, Body Mass Index (BMI), duration of AN, and duration of amenorrhea. RESULTS 675 studies were reviewed, of which 19 fit the inclusion criteria and were included in the final review, investigating a total of 1119 participants; 10 of the 19 included studies were double-blind RCTs. The remaining studies consisted of prospective observational studies, a retrospective cohort study, a case-control study and five non-randomised control trials. Bisphosphonates were effective in increasing BMD in adult women with AN, while estrogen administered transdermally resulted in significant increases in BMD in mature adolescents with AN. Administration of oral contraceptives (OC) did not significantly increase BMD in randomised or controlled trials, however, lifetime OC use was associated with higher spinal BMD. CONCLUSION Future research should clarify the safety of long-term bisphosphonate use in adult women with AN, and verify that transdermal estrogen replacement increases BMD in women with AN.
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Affiliation(s)
- Lauren Robinson
- Institute of Child Health, University College London, Gower Street, London WC1E 6BT, UK; Dept. of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, USA.
| | - Victoria Aldridge
- Institute of Child Health, University College London, Gower Street, London WC1E 6BT, UK
| | - Emma M Clark
- Musculoskeletal Research Unit, University of Bristol, Bristol, UK
| | - Madhusmita Misra
- Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Nadia Micali
- Institute of Child Health, University College London, Gower Street, London WC1E 6BT, UK,Dept. of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, USA
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11
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Svedlund A, Pettersson C, Tubic B, Magnusson P, Swolin-Eide D. Vitamin D status in young Swedish women with anorexia nervosa during intensive weight gain therapy. Eur J Nutr 2016; 56:2061-2067. [PMID: 27307256 DOI: 10.1007/s00394-016-1244-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 06/07/2016] [Indexed: 11/26/2022]
Abstract
PURPOSE Anorexia nervosa (AN) is associated with reduced bone mass and an increased fracture risk. The aim was to evaluate the vitamin D status and the association with body mass index (BMI), fat mass and bone mineral density (BMD) in patients with severe AN during a prospective intervention study of intensive nutrition therapy. METHODS This study comprised 25 Swedish female AN patients (20.1 ± 2.3 years), who were treated as inpatients for 12 weeks with a high-energy diet. Serum 25-hydroxyvitamin D (25(OH)D), calcium, phosphate and parathyroid hormone (PTH) were measured. BMD and body composition were assessed by dual-energy X-ray absorptiometry at study start and after 12 weeks. RESULTS Twenty-two patients completed the study. The mean weight gain was 9.9 kg and BMI (mean ± SD) increased from 15.5 ± 0.9 to 19.0 ± 0.9 kg/m2, P < 0.0001. Fat mass increased from median 12 to 27 %. The median serum 25(OH)D level was 84 nmol/L at baseline, which decreased to 76 nmol/L, P < 0.05. PTH increased from median 21.9 to 30.0 ng/L, P < 0.0001. BMC increased during the study period, P < 0.001. CONCLUSIONS Serum 25(OH)D levels were adequate both at study start and completion, however, nominally decreased after the 12-week nutritional intervention. PTH increased subsequently, which coincide with the decreased 25(OH)D levels. The reduction in 25(OH)D could be due to an increased storage of vitamin D related to the increase in fat mass since vitamin D is sequestered in adipose tissue.
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Affiliation(s)
- Anna Svedlund
- Department of Pediatrics, Institute of Clinical Sciences, The Queen Silvia Children's Hospital, Sahlgrenska Academy, Gothenburg University, Rondvägen 15, SE-416 85, Göteborg, Sweden.
| | - Cecilia Pettersson
- Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, Gothenburg University, Göteborg, Sweden
| | - Bojan Tubic
- Department of Pediatrics, Institute of Clinical Sciences, The Queen Silvia Children's Hospital, Sahlgrenska Academy, Gothenburg University, Rondvägen 15, SE-416 85, Göteborg, Sweden
| | - Per Magnusson
- Department of Clinical Chemistry and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Diana Swolin-Eide
- Department of Pediatrics, Institute of Clinical Sciences, The Queen Silvia Children's Hospital, Sahlgrenska Academy, Gothenburg University, Rondvägen 15, SE-416 85, Göteborg, Sweden
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12
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Scott A, Choi K, Mookherjee N, Hoppa R, Larcombe L. The biochemical signatures of stress: A preliminary analysis of osteocalcin concentrations and macroscopic skeletal changes associated with stress in the 13th - 17th centuries black friars population. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2015; 159:596-606. [DOI: 10.1002/ajpa.22915] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 11/12/2015] [Accepted: 11/19/2015] [Indexed: 11/09/2022]
Affiliation(s)
- A.B. Scott
- Department of Anthropology; University of Manitoba; Winnipeg MB R3T 2N2 Canada
| | - K.Y. Choi
- Department of Immunology; University of Manitoba; Winnipeg MB R3E 0T5 Canada
| | - N. Mookherjee
- Department of Immunology; University of Manitoba; Winnipeg MB R3E 0T5 Canada
| | - R.D. Hoppa
- Department of Anthropology; University of Manitoba; Winnipeg MB R3T 2N2 Canada
| | - L.A. Larcombe
- Department of Anthropology; University of Manitoba; Winnipeg MB R3T 2N2 Canada
- Department of Internal Medicine; University of Manitoba; Winnipeg MB R3T 2N2 Canada
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13
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Abstract
In the past 15 years, the field of physiology has been radically challenged by landmark studies using novel tools of genetic engineering. Particular to our interest, the reciprocal interactions between the skeleton and the nervous system were shown to be major ones. The demonstration that brain, via multiple pathways, is a powerful regulator of bone growth, has shed light on an important central regulation of skeletal homeostasis. More recently, it was shown that bone might return the favor to the brain through the secretion of a bone-derived hormone, osteocalcin. The skeleton influences development and cognitive functions of the central nervous system at different stages throughout life suggesting an intimate dialogue between bone and brain.
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Affiliation(s)
- Alexandre Chamouni
- Centre de Médecine Moléculaire, Institut Necker-Enfants Malades (INEM), 75014, Paris, France
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14
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Abstract
Recent developments in endocrinology, made possible by the combination of mouse genetics, integrative physiology and clinical observations have resulted in rapid and unanticipated advances in the field of skeletal biology. Indeed, the skeleton, classically viewed as a structural scaffold necessary for mobility, and regulator of calcium-phosphorus homoeostasis and maintenance of the haematopoietic niche has now been identified as an important regulator of male fertility and whole-body glucose metabolism, in addition to the classical insulin target tissues. These seminal findings confirm bone to be a true endocrine organ. This review is intended to detail the key events commencing from the elucidation of osteocalcin (OC) in bone metabolism to identification of new and emerging candidates that may regulate energy metabolism independently of OC.
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Affiliation(s)
- K J Oldknow
- Developmental BiologyThe Roslin Institute, Edinburgh, UK
| | - V E MacRae
- Developmental BiologyThe Roslin Institute, Edinburgh, UK
| | - C Farquharson
- Developmental BiologyThe Roslin Institute, Edinburgh, UK
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15
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Méquinion M, Caron E, Zgheib S, Stievenard A, Zizzari P, Tolle V, Cortet B, Lucas S, Prévot V, Chauveau C, Viltart O. Physical activity: benefit or weakness in metabolic adaptations in a mouse model of chronic food restriction? Am J Physiol Endocrinol Metab 2015; 308:E241-55. [PMID: 25465889 DOI: 10.1152/ajpendo.00340.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In restrictive-type anorexia nervosa (AN) patients, physical activity is usually associated with food restriction, but its physiological consequences remain poorly characterized. In female mice, we evaluated the impact of voluntary physical activity with/without chronic food restriction on metabolic and endocrine parameters that might contribute to AN. In this protocol, FRW mice (i.e., food restriction with running wheel) reached a crucial point of body weight loss (especially fat mass) faster than FR mice (i.e., food restriction only). However, in contrast to FR mice, their body weight stabilized, demonstrating a protective effect of a moderate, regular physical activity. Exercise delayed meal initiation and duration. FRW mice displayed food anticipatory activity compared with FR mice, which was strongly diminished with the prolongation of the protocol. The long-term nature of the protocol enabled assessment of bone parameters similar to those observed in AN patients. Both restricted groups adapted their energy metabolism differentially in the short and long term, with less fat oxidation in FRW mice and a preferential use of glucose to compensate for the chronic energy imbalance. Finally, like restrictive AN patients, FRW mice exhibited low leptin levels, high plasma concentrations of corticosterone and ghrelin, and a disruption of the estrous cycle. In conclusion, our model suggests that physical activity has beneficial effects on the adaptation to the severe condition of food restriction despite the absence of any protective effect on lean and bone mass.
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Affiliation(s)
- Mathieu Méquinion
- University Lille (ULCO, USTL, Lille2), Lille, France; Development and Plasticity of Postnatal Brain, UMR 837 Institut National de la Sante et de la Recherche Medicale (INSERM), Lille, France; Physiopathology of Inflammatory Bone diseases, EA4490, Boulogne sur Mer, France
| | - Emilie Caron
- Development and Plasticity of Postnatal Brain, UMR 837 Institut National de la Sante et de la Recherche Medicale (INSERM), Lille, France
| | - Sara Zgheib
- University Lille (ULCO, USTL, Lille2), Lille, France; Physiopathology of Inflammatory Bone diseases, EA4490, Boulogne sur Mer, France
| | - Aliçia Stievenard
- University Lille (ULCO, USTL, Lille2), Lille, France; Molecular Events Associated With Early stages of Parkinson's Disease UMR 837 INSERM, Lille, France
| | - Philippe Zizzari
- Psychiatry and Neurosciences Center, UMR 894 INSERM, Paris, France; and
| | - Virginie Tolle
- Psychiatry and Neurosciences Center, UMR 894 INSERM, Paris, France; and
| | - Bernard Cortet
- University Lille (ULCO, USTL, Lille2), Lille, France; Department of Rheumatology, Centre Hospitalier Universitaire Régional, Lille, France
| | - Stéphanie Lucas
- University Lille (ULCO, USTL, Lille2), Lille, France; Physiopathology of Inflammatory Bone diseases, EA4490, Boulogne sur Mer, France
| | - Vincent Prévot
- University Lille (ULCO, USTL, Lille2), Lille, France; Development and Plasticity of Postnatal Brain, UMR 837 Institut National de la Sante et de la Recherche Medicale (INSERM), Lille, France
| | - Christophe Chauveau
- University Lille (ULCO, USTL, Lille2), Lille, France; Physiopathology of Inflammatory Bone diseases, EA4490, Boulogne sur Mer, France
| | - Odile Viltart
- University Lille (ULCO, USTL, Lille2), Lille, France; Development and Plasticity of Postnatal Brain, UMR 837 Institut National de la Sante et de la Recherche Medicale (INSERM), Lille, France;
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16
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Ferron M, Lacombe J. Regulation of energy metabolism by the skeleton: Osteocalcin and beyond. Arch Biochem Biophys 2014; 561:137-46. [DOI: 10.1016/j.abb.2014.05.022] [Citation(s) in RCA: 131] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Revised: 05/19/2014] [Accepted: 05/22/2014] [Indexed: 12/30/2022]
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17
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Karsenty G, Oury F. Regulation of male fertility by the bone-derived hormone osteocalcin. Mol Cell Endocrinol 2014; 382:521-526. [PMID: 24145129 PMCID: PMC3850748 DOI: 10.1016/j.mce.2013.10.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 10/08/2013] [Accepted: 10/09/2013] [Indexed: 12/27/2022]
Abstract
Traditionally, bone has been viewed as a relatively static tissue only fulfilling mechanical and scaffolding function. In the past decade however, this classical view of the bone has considerably evolved towards a more complex picture. It is now clear that the skeleton is not only a recipient for hormonal input but it is also an endocrine organ itself. Through the secretion of an osteoblast-derived molecule, osteocalcin, the skeleton regulates glucose homeostasis and male reproductive functions. When undercarboxylated, osteocalcin acts following its binding to a G-coupled receptor, Gprc6a, on pancreatic β cells to increase insulin secretion, on muscle and white adipose tissue to promote glucose homeostasis and on Leydig cells of the testis to favor testosterone biosynthesis. More recently, it was also shown that osteocalcin acts via a pancreas-bone-testis axis that regulates, independently of and in parallel to the hypothalamus-pituitary-testis axis, male reproductive functions by promoting testosterone biosynthesis. Lastly, in trying to expand the biological relevance of osteocalcin from mouse to human, it was shown that Gprc6a is a potential new susceptibility locus for primary testicular failure in humans. Altogether, these results shed new light on the importance of the endocrine role of the skeleton and also provide credence to the search for additional endocrine functions of this organ.
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Affiliation(s)
- Gerard Karsenty
- Columbia University, Department of Genetics and Development, HHSC 1602, 701 West 168th Street, New York, NY 10032, USA.
| | - Franck Oury
- Columbia University, Department of Genetics and Development, HHSC 1602, 701 West 168th Street, New York, NY 10032, USA
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Londono J, Valencia P, Santos AM, Gutiérrez LF, Baquero R, Valle-Oñate R. Risk factors and prevalence of osteoporosis in premenopausal women from poor economic backgrounds in Colombia. Int J Womens Health 2013; 5:425-30. [PMID: 23901298 PMCID: PMC3720571 DOI: 10.2147/ijwh.s45170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION The prevalence of osteoporosis in premenopausal women along with associated risk factors has not been well elucidated. Recent studies have shown that poverty is a risk factor for osteoporosis. OBJECTIVE To determine the prevalence of osteoporosis and its risk factors in a group of premenopausal women of poor economic background in Colombia. MATERIALS AND METHODS The study comprised 1483 women between 35 and 53 years of age with at least one risk factor for osteoporosis. Demographic characteristics, reproductive factors, comorbidities, and risk factors for osteoporosis were evaluated. Lumbar vertebrae (L2-L4) and the femur neck were assessed using dual-energy X-ray absorptiometry. RESULTS Of the 1483 patients, 1443 (97.3%) had at least one risk factor for osteoporosis and 40 (2.7%) had no risk factors. Patients with one risk factor were referred to have a dual-energy X-ray absorptiometry scan, which 795 women completed. Osteopenia was found in 30.5% and osteoporosis in 4.8% of these women. The majority of these women were homemakers, and 18.5% of the patients with osteoporosis were also illiterate (P < 0.001). The risk factors identified in this population were: hypothyroidism (odds ratio [OR] = 5.19, 95% confience interval [CI]:1.6-16), age over 45 years old (OR = 1.13, 95% CI: 1.0-1.2), a history of malnutrition or low birth weight (OR = 2.35, 95% CI: 1.0-5.2), or early-onset menopause (OR = 3.4, 95% CI: 1.6-7.2). CONCLUSION Premenopausal Colombian women from impoverished areas showed increased rates of osteopenia and osteoporosis compared with the data described in the current literature. Hypothyroidism was an outstanding risk factor in Colombian premenopausal women with osteoporosis. This shows the influence of poverty and other risk factors on the onset of osteoporosis in women aged 35-53 years.
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Affiliation(s)
- John Londono
- Rheumatology Department, Universidad de La Sabana, Chía, Cundinamarca, Colombia
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19
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Revelas A. Eating disorders are real treatable medical illnesses. S Afr Fam Pract (2004) 2013. [DOI: 10.1080/20786204.2013.10874346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
- A Revelas
- Department of Pathology, St Nicolas General Hospital, Crete
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20
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Méquinion M, Langlet F, Zgheib S, Dickson S, Dehouck B, Chauveau C, Viltart O. Ghrelin: central and peripheral implications in anorexia nervosa. Front Endocrinol (Lausanne) 2013; 4:15. [PMID: 23549309 PMCID: PMC3581855 DOI: 10.3389/fendo.2013.00015] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 02/01/2013] [Indexed: 11/15/2022] Open
Abstract
Increasing clinical and therapeutic interest in the neurobiology of eating disorders reflects their dramatic impact on health. Chronic food restriction resulting in severe weight loss is a major symptom described in restrictive anorexia nervosa (AN) patients, and they also suffer from metabolic disturbances, infertility, osteopenia, and osteoporosis. Restrictive AN, mostly observed in young women, is the third largest cause of chronic illness in teenagers of industrialized countries. From a neurobiological perspective, AN-linked behaviors can be considered an adaptation that permits the endurance of reduced energy supply, involving central and/or peripheral reprograming. The severe weight loss observed in AN patients is accompanied by significant changes in hormones involved in energy balance, feeding behavior, and bone formation, all of which can be replicated in animals models. Increasing evidence suggests that AN could be an addictive behavior disorder, potentially linking defects in the reward mechanism with suppressed food intake, heightened physical activity, and mood disorder. Surprisingly, the plasma levels of ghrelin, an orexigenic hormone that drives food-motivated behavior, are increased. This increase in plasma ghrelin levels seems paradoxical in light of the restrained eating adopted by AN patients, and may rather result from an adaptation to the disease. The aim of this review is to describe the role played by ghrelin in AN focusing on its central vs. peripheral actions. In AN patients and in rodent AN models, chronic food restriction induces profound alterations in the « ghrelin » signaling that leads to the development of inappropriate behaviors like hyperactivity or addiction to food starvation and therefore a greater depletion in energy reserves. The question of a transient insensitivity to ghrelin and/or a potential metabolic reprograming is discussed in regard of new clinical treatments currently investigated.
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Affiliation(s)
- Mathieu Méquinion
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
| | - Fanny Langlet
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
| | - Sara Zgheib
- Pathophysiology of inflammatory of bone diseases, Université Lille Nord de France-ULCO – Lille 2Boulogne sur Mer, France
| | - Suzanne Dickson
- Department of Physiology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
- Department of Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of GothenburgGothenburg, Sweden
| | - Bénédicte Dehouck
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
- Université Lille Nord de France – Université d’ArtoisLiévin, France
| | - Christophe Chauveau
- Pathophysiology of inflammatory of bone diseases, Université Lille Nord de France-ULCO – Lille 2Boulogne sur Mer, France
| | - Odile Viltart
- UMR INSERM 837, Development and Plasticity of Postnatal BrainLille, France
- Université Lille Nord de France-USTL (Lille 1)Villeneuve d’Ascq, France
- *Correspondence: Odile Viltart, Development and Plasticity of the Postnatal Brain, Team 2, Jean-Pierre Aubert Research Center, UMR INSERM 837, Bât Biserte, 1 place de Verdun, 59,045 Lille cedex, France. e-mail:
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21
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Ferrari S, Bianchi ML, Eisman JA, Foldes AJ, Adami S, Wahl DA, Stepan JJ, de Vernejoul MC, Kaufman JM. Osteoporosis in young adults: pathophysiology, diagnosis, and management. Osteoporos Int 2012; 23:2735-48. [PMID: 22684497 DOI: 10.1007/s00198-012-2030-x] [Citation(s) in RCA: 139] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 05/14/2012] [Indexed: 01/08/2023]
Abstract
Postmenopausal osteoporosis is mainly caused by increased bone remodeling resulting from estrogen deficiency. Indications for treatment are based on low areal bone mineral density (aBMD, T-score ≤ -2.5), typical fragility fractures (spine or hip), and more recently, an elevated 10-year fracture probability (by FRAX®). In contrast, there is no clear definition of osteoporosis nor intervention thresholds in younger individuals. Low aBMD in a young adult may reflect a physiologically low peak bone mass, such as in lean but otherwise healthy persons, whereas fractures commonly occur with high-impact trauma, i.e., without bone fragility. Furthermore, low aBMD associated with vitamin D deficiency may be highly prevalent in some regions of the world. Nevertheless, true osteoporosis in the young can occur, which we define as a T-score below -2.5 at spine or hip in association with a chronic disease known to affect bone metabolism. In the absence of secondary causes, the presence of fragility fractures, such as in vertebrae, may point towards genetic or idiopathic osteoporosis. In turn, treatment of the underlying condition may improve bone mass as well. In rare cases, a bone-specific treatment may be indicated, although evidence is scarce for a true benefit on fracture risk. The International Osteoporosis Foundation (IOF) convened a working group to review pathophysiology, diagnosis, and management of osteoporosis in the young, excluding children and adolescents, and provide a screening strategy including laboratory exams for a systematic approach of this condition.
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Affiliation(s)
- S Ferrari
- Division of Bone Diseases, Faculty of Medicine, Geneva University Hospital, Geneva, Switzerland.
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22
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Abstract
The mouse genetic revolution has shown repeatedly that most organs have more functions than expected. This has led to the realization that, in addition to a molecular and cellular approach, there is a need for a whole-organism study of physiology. The skeleton is an example of how a whole-organism approach to physiology can broaden the functions of a given organ, reveal connections of this organ with others such as the brain, pancreas and gut, and shed new light on the pathogenesis of degenerative diseases affecting multiple organs.
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Affiliation(s)
- Gérard Karsenty
- Department of Genetics and Development, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA.
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23
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Strike MK, Norris S, Kearney S, Norris ML. More than just milk: a review of prolactin's impact on the treatment of anorexia nervosa. EUROPEAN EATING DISORDERS REVIEW 2011; 20:e85-90. [PMID: 21774041 DOI: 10.1002/erv.1119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE In completing this review, we aim to educate readers about the physiological importance of the hormone prolactin (PRL) in the treatment of patients with anorexia nervosa (AN). METHOD A comprehensive review of PRL was undertaken using existing published literature with specific focus on domains pertinent to the treatment of AN. RESULTS Prolactin influences multiple biological processes throughout the body. Disruption in its regulation can impact women's health issues such as menstruation and bone health, which are pertinent to AN treatment. The use of antipsychotics with high D2 receptor affinity for the augmented treatment of AN increases the potential risk of PRL-mediated adverse effects. DISCUSSION Although not intrinsic to underlying disease underpinnings, PRL has the capacity to affect and influence multiple outcome variables in treatment of patients with AN. Improved understanding, better screening and the completion of further prospective research are necessary to help facilitate and incorporate ongoing knowledge translation.
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Abstract
An association between anorexia nerviosa (AN) and low bone mass has been demonstrated. Bone loss associated with AN involves hormonal and nutritional impairments, though their exact contribution is not clearly established. We compared bone mass in AN patients with women of similar weight with no criteria for AN, and a third group of healthy, normal-weight, age-matched women. The study included forty-eight patients with AN, twenty-two healthy eumenorrhoeic women with low weight (LW group; BMI < 18·5 kg/m2) and twenty healthy women with BMI >18·5 kg/m2 (control group), all of similar age. We measured lean body mass, percentage fat mass, total bone mineral content (BMC) and bone mineral density in lumbar spine (BMD LS) and in total (tBMD). We measured anthropometric parameters, leptin and growth hormone. The control group had greater tBMD and BMD LS than the other groups, with no differences between the AN and LW groups. No differences were found in tBMD, BMD LS and total BMC between the restrictive (n 25) and binge–purge type (n 23) in AN patients. In AN, minimum weight (P = 0·002) and percentage fat mass (P = 0·02) explained BMD LS variation (r2 0·48) and minimum weight (r2 0·42; P = 0·002) for tBMD in stepwise regression analyses. In the LW group, BMI explained BMD LS (r2 0·72; P = 0·01) and tBMD (r2 0·57; P = 0·04). We concluded that patients with AN had similar BMD to healthy thin women. Anthropometric parameters could contribute more significantly than oestrogen deficiency in the achievement of peak bone mass in AN patients.
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25
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Abstract
Since the advent on non-invasive in vivo clinical bone densitometry, investigators have reported that regional bone mineral material loss accompanies the onset and continuance of anorexia nervosa (AN). Initial single-energy photon absorptiometric (SPA) studies were followed by a succession of dual-energy X-ray absorptiometric (DXA) investigations, and a few single-energy quantitative computer assisted tomographic (SEQCT) bone densitometry vertebral measurements. Although most all DXA studies found a relatively small diminution (approximately 3%) of bone mineral material at lumbar vertebral and proximal femoral bone-sites of AN-afflicted adolescent girls and young women, these findings have been consensually interpreted and near-universally accepted as losses of actual bone mineral material accompanying AN. It has also been claimed by some that about 50% of those beset by AN while still young adolescents were osteoporotic. Nonetheless, over the last intervening 2 decades of these studies, no specific underlying direct bone-biological causal link between AN and trabecular bone material loss has yet been uncovered. The present exposition shows that in vivo SPA, DXA, and SEQCT measurements of bone mineral material losses do not constitute evidence of actual loss of bone material, and that the attribution of osteopenia and osteoporosis to AN-afflicted younger adolescent girls is not sustainable. Rather, the full gamut of these reported bone material "losses" can be accounted for by the already well-documented AN-induced changes in the anthropometrics and compositional mixes of extra-osseous soft tissues (primarily in a very noticeable reduction of extra-skeletal fat) and intra-osseous bone marrow yellowing (marrow hypoplasia and marrow cell necrosis). These changes in soft tissue compositions and anthropometrics alone have been shown to be sufficient to cause in vivo SPA, DXA, and SEQCT to systematically mis-estimate true bone material density and erroneously register changes in bone mineral content, even when no actual changes in bone mineral material have occurred. As a result, it is seen that in vivo bone densitometry methodologies have not demonstrated that AN induces actual loss of bone mineral material. It is also demonstrated that DXA and SEQCT bone density measurements of predominantly trabecular bone-sites cannot be relied upon as gauges of heightened propensity for early (or late) osteoporotic development.
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Affiliation(s)
- H H Bolotin
- School of Medical Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
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26
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Hofman M, Landewé-Cleuren S, Wojciechowski F, Kruseman AN. Prevalence and clinical determinants of low bone mineral density in anorexia nervosa. Eur J Intern Med 2009; 20:80-4. [PMID: 19237098 DOI: 10.1016/j.ejim.2008.04.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2007] [Revised: 03/04/2008] [Accepted: 04/27/2008] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To determine the prevalence of low bone mass in anorexia nervosa (AN) and the association with clinical parameters. METHODS A cross-sectional study on 286 Caucasian women with AN. Bone mineral density (BMD) was measured with DXA. Low BMD was defined as a Z-score <or= -1.0 in at least one site (lumbar spine or femoral neck). RESULTS A Z-score of <or= -1.0 in at least one of these sites was found in 46.9%. In comparison with the patients with normal BMD, in patients with a low BMD both the BMI at the time of DXA (p=0.005) and the lowest BMI ever (p<0.001) was lower. These patients also had a longer duration of AN (p=0.047). The decline of BMI per year between highest BMI ever and BMI at time of DXA was more rapid in subjects with a normal BMD (p=0.016) as compared to patients with low BMD. Low BMD was found to be independently associated with 'lowest BMI ever' (OR: 0.78; 95%CI=0.66-0.93), and with 'BMI decline per year' (OR: 0.83; 95%CI=0.71-0.97). CONCLUSION We conclude that low BMD is frequent in AN. The best indicator of low BMD appeared to be the lowest reported BMI ever.
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Affiliation(s)
- Marielle Hofman
- Department of Internal Medicine, Division of Endocrinology, University Hospital Maastricht, The Netherlands
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27
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Rigaud D, Brondel L, Poupard AT, Talonneau I, Brun JM. A randomized trial on the efficacy of a 2-month tube feeding regimen in anorexia nervosa: A 1-year follow-up study. Clin Nutr 2007; 26:421-9. [PMID: 17499892 DOI: 10.1016/j.clnu.2007.03.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 03/28/2007] [Accepted: 03/28/2007] [Indexed: 11/19/2022]
Abstract
BACKGROUND & AIMS Despite the high mortality rate in malnourished anorexia nervosa (AN) patients, very few trials have prospectively studied the efficacy of tube feeding. METHODS This open prospective study was conducted in malnourished AN patients, who were randomized in tube feeding (n=41) or control (n=40) groups during a 2-month period. Thereafter, body weight, body mass gain, energy intake, eating behavior and relapse rates were compared during a 1-year follow-up, using paired Student t-test and ANOVA. RESULTS At the end of the 2-months period, weight gain was 39% higher in the tube feeding group than in the control group (194+/-14 vs 126+/-19g/day; P<0.01). The fat-free mass gain was greater in the tube-feeding group: 109+/-14 vs 61+/-17g/day (P<0.01). Energy intake was higher in the tube feeding group than in the control group (P<0.05), as well as the decrease in bingeing episodes (P<0.01). Most patients thought that CEN improved their eating disorder. After discharge, the relapse-free period was longer in the CEN group than in the control one: 34.3+/-8.2 weeks vs 26.8+/-7.5 weeks (P<0.05). CONCLUSION CEN is helpful in malnourished AN patients for weight restoration, without hindrance on the eating behavior therapy nor inducing a more rapid relapse.
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Affiliation(s)
- Daniel Rigaud
- Service d'Endocrinologie et Nutrition, CHU Le Bocage, 21079, Dijon, France.
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28
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Abdallah BM, Ding M, Jensen CH, Ditzel N, Flyvbjerg A, Jensen TG, Dagnaes-Hansen F, Gasser JA, Kassem M. Dlk1/FA1 is a novel endocrine regulator of bone and fat mass and its serum level is modulated by growth hormone. Endocrinology 2007; 148:3111-21. [PMID: 17446189 DOI: 10.1210/en.2007-0171] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fat and bone metabolism are two linked processes regulated by several hormonal factors. Fetal antigen 1 (FA1) is the soluble form of dlk1 (delta-like 1), which is a member of the Notch-Delta family. We previously identified FA1 as a negative regulator of bone marrow mesenchymal stem cell differentiation. Here, we studied the effects of circulating FA1 on fat and bone mass in vivo by generating mice expressing high serum levels of FA1 (FA1 mice) using the hydrodynamic-based gene transfer procedure. We found that increased serum FA1 levels led to a significant reduction in total body weight, fat mass, and bone mass in a dose-dependent manner. Reduced bone mass in FA1 mice was associated with the inhibition of mineral apposition rate and bone formation rates by 58 and 72%, respectively. Because FA1 is colocalized with GH in the pituitary gland, we explored the possible modulation of serum FA1 by GH. Serum levels of IGF-I and IGF binding proteins did not change in FA1 mice, whereas increasing serum GH in normal mice using hydrodynamic-based gene transfer procedure dramatically reduced serum FA1 levels by 60%. Conversely, serum FA1 was increased 450% in hypophysectomized mice, and this high level was reduced by 40% during GH treatment. In conclusion, our data identify the FA1 as a novel endocrine factor regulating bone mass and fat mass in vivo, and its serum levels are regulated by GH. FA1 thus provides a novel class of developmental molecules that regulate physiological functions of the postnatal organisms.
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Affiliation(s)
- Basem M Abdallah
- Department of Endocrinology, Clinic for Molecular Endocrinology Treatment Laboratory, Odense University Hospital, Medical Biotechnology Center, University of South Denmark, DK-5000 Odense C, Denmark.
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29
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Diamanti A, Bizzarri C, Gambarara M, Calce A, Montecchi F, Cappa M, Bianco G, Castro M. Bone mineral density in adolescent girls with early onset of anorexia nervosa. Clin Nutr 2007; 26:329-34. [PMID: 17307279 DOI: 10.1016/j.clnu.2006.12.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 12/20/2006] [Accepted: 12/25/2006] [Indexed: 11/17/2022]
Abstract
BACKGROUND & AIMS To assess prevalence of bone mineral density (BMD) reduction and relationship between bone mineral status and anthropometric assessment, nutritional intake and physical activity in adolescents with early anorexia nervosa (AN). METHODS Fifty-seven consecutive AN patients and 57 healthy controls underwent anthropometric status, bone density, body composition and physical activity evaluations. In AN patients clinical features and nutritional intake were also assessed. RESULTS Thirty-five patients with AN (62%) and 44 healthy subjects (77%) (pNS) showed normal BMD. Mean value of BMD Z-score was -0.6+/-0.9 in AN patients and -0.2+/-1.4 in controls (pNS). Weight at diagnosis and lean mass resulted the main predictor of bone loss but also height, best weight before diagnosis and BMI resulted correlated with bone mineral status in AN patients. Additionally, AN patients maintained good levels of protein intake and sport activity CONCLUSIONS Early diagnosis may prevent bone loss in AN patients. Protein intake and moderate physical activity seem to be useful to maintain an adequate bone mineral status.
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Affiliation(s)
- Antonella Diamanti
- Gastroenterology and Nutrition Unit, Pediatric Hospital Bambino Gesù, Piazza S. Onofrio, 4-00165 Rome, Italy.
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Viapiana O, Gatti D, Dalle Grave R, Todesco T, Rossini M, Braga V, Idolazzi L, Fracassi E, Adami S. Marked increases in bone mineral density and biochemical markers of bone turnover in patients with anorexia nervosa gaining weight. Bone 2007; 40:1073-7. [PMID: 17240212 DOI: 10.1016/j.bone.2006.11.015] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Revised: 11/14/2006] [Accepted: 11/22/2006] [Indexed: 11/19/2022]
Abstract
Anorexia nervosa (AN) is a life-threatening eating disorder characterized by an inability to maintain a normal body weight and amenorrhoea, often associated with osteoporosis and increased risk of fragility fractures. Bone metabolism, including markers of bone turnover (serum total alkaline phosphatase, bone alkaline phosphatase [bone AP], osteocalcin [OC] and type I collagen C-telopeptide breakdown products [sCTX]) and bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) at the spine and at the hip, were evaluated in 55 consecutive women with AN undergoing a 3-month intensive nutritional rehabilitation program. The control group was constituted of 25 healthy young medical students. In AN patients body weight increased during the 3-month nutritional program from 37.8+/-5.1 (mean+/-SD) to 51.5+/-4.5 kg. The corresponding BMI rose to values >17.5 kg/m(2) in all patients. Mean BMD significantly rose by 2.6+/-3.5% and 1.1+/-3.6% at the hip and at the spine, respectively. The markers of bone formation, serum bone AP and osteocalcin, significantly rose by two-folds, while sCTX decreased by 16%. The changes in hip BMD were positively related (p<0.005) to changes in body weight and in bone AP (p<0.02) while the changes in spine BMD were positively related to changes in serum osteocalcin (p<0.05). In the 25 patients who attended the 12-month posttreatment control, mean body weight significantly decreased by 3.6+/-6.0 kg and this was not associated with any significant change in BMD values. In the patients in whom BMI fell again below 17.5 kg/m(2) hip BMD values decreased significantly. On the contrary, in the patients who maintained BMI >17.5 kg/m(2), BMD values continued to rise up to values over the 15-month observation of 4.8+/-6.2 and 7.1+/-12.1 at the spine and hip, respectively. In conclusion, we have demonstrated that substantial gains in weight in women with chronic AN are associated with remarkable increases in BMD at both the hip and the spine. If weight is maintained, the overall improvement approach 1 SD within 1 year. The changes in both weight and BMD are correlated with improvements in bone formation markers and diminutions in a marker of bone resorption.
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Affiliation(s)
- Ombretta Viapiana
- Department of Rheumathology, University of Verona, Valeggio Hospital, 37067 Valeggio S/Mincio, Verona, Italy.
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Ebert R, Schütze N, Schilling T, Seefried L, Weber M, Nöth U, Eulert J, Jakob F. Influence of hormones on osteogenic differentiation processes of mesenchymal stem cells. Expert Rev Endocrinol Metab 2007; 2:59-78. [PMID: 30743749 DOI: 10.1586/17446651.2.1.59] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Bone development, regeneration and maintenance are governed by osteogenic differentiation processes from mesenchymal stem cells through to mature bone cells, which are directed by local growth and differentiation factors and modulated strongly by hormones. Mesenchymal stem cells develop from both mesoderm and neural crest and can give rise to development, regeneration and maintenance of mesenchymal tissues, such as bone, cartilage, muscle, tendons and discs. There are only limited data regarding the effects of hormones on early events, such as regulation of stemness and maintenance of the mesenchymal stem cell pool. Hormones, such as estrogens, vitamin D-hormone and parathyroid hormone, besides others, are important modulators of osteogenic differentiation processes and bone formation, starting off with fate decision and the development of osteogenic offspring from mesenchymal stem cells, which end up in osteoblasts and osteocytes. Hormones are involved in fetal bone development and regeneration and, in childhood, adolescence and adulthood, they control adaptive needs for growth and reproduction, nutrition, physical power and crisis adaptation. As in other tissues, aging in mesenchymal stem cells and their osteogenic offspring is accompanied by the accumulation of genomic and proteomic damage caused by oxidative burden and insufficient repair. Failsafe programs, such as apoptosis and cellular senescence avoid tumorigenesis. Hormones can influence the pace of such events, thus supporting the quality of tissue regeneration in aging organisms in vivo; for example, by delaying osteoporosis development. The potential for hormones in systemic therapeutic strategies is well appreciated and some concepts are approved for clinical use already. Their potential for cell-based therapeutic strategies for tissue regeneration is probably underestimated and could enhance the quality of tissue-engineering constructs for transplantation and the concept of in situ-guided tissue regeneration.
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Affiliation(s)
- Regina Ebert
- a University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Norbert Schütze
- b University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Tatjana Schilling
- c University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Lothar Seefried
- d University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Meike Weber
- e University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Ulrich Nöth
- f University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Jochen Eulert
- g University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
| | - Franz Jakob
- h University of Wuerzburg, Orthopedic Center for Musculoskeletal Research, Brettreichstrasse 11, 97074 Wuerzburg, Germany.
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Csermely T, Halvax L, Vizer M, Drozgyik I, Tamás P, Göcze P, Szabó I, Jeges S, Szilágyi A. Relationship between adolescent amenorrhea and climacteric osteoporosis. Maturitas 2006; 56:368-74. [PMID: 17161926 DOI: 10.1016/j.maturitas.2006.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2006] [Revised: 10/09/2006] [Accepted: 10/19/2006] [Indexed: 11/17/2022]
Abstract
OBJECTIVES The relationship between climacteric osteoporosis and disturbances in menstrual cycle during adolescence was examined. METHODS Seven hundred and seventy-one questionnaires were shared out among women visiting the outpatient department for climacteric complaints for the first time between 2001 and 2004. Questions revealed the age, age at menarche and menopause, the regularity or irregularity of menstrual cycle during adolescence and adult ages. The bone mineral density was examined using the Dual Energy X-ray Absorptiometry (DEXA) method on the lumbar spine. RESULTS Six hundred and thirty-five of the 771 questionnaires were suitable for analysis. Osteoporosis was observed in 30.1% of the cases. Age, age at the menarche or at the menopause did not alter in the subgroups with or without osteoporosis. The incidence and severity of osteoporosis were significantly higher in patients reporting secondary amenorrhea during adolescent ages (42.1%; average BMD of the lumbar spine 71.6+/-3.9), as compared to the patients with normal cycle (30.4%; average BMD of the lumbar spine 84.8+/-7.8). No correlation between the occurrence of osteoporosis and the frequency of menstrual cycle during adulthood was observed. CONCLUSIONS Secondary amenorrhea during the years of adolescence might play a role in the development of more severe osteoporosis in menopause.
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Affiliation(s)
- Tamás Csermely
- Department of Obstetrics and Gynecology, University of Pécs, Faculty of Medicine, H-7624 Pécs, Edesanyák útja 17, Hungary.
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Donahue SW, Galley SA, Vaughan MR, Patterson-Buckendahl P, Demers LM, Vance JL, McGee ME. Parathyroid hormone may maintain bone formation in hibernating black bears (Ursus americanus) to prevent disuse osteoporosis. J Exp Biol 2006; 209:1630-8. [PMID: 16621944 DOI: 10.1242/jeb.02185] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
SUMMARY
Mechanical unloading of bone causes an imbalance in bone formation and resorption leading to bone loss and increased fracture risk. Black bears(Ursus americanus) are inactive for up to six months during hibernation, yet bone mineral content and strength do not decrease with disuse or aging. To test whether hibernating bears have biological mechanisms to prevent disuse osteoporosis, we measured the serum concentrations of hormones and growth factors involved in bone metabolism and correlated them with the serum concentration of a bone formation marker (osteocalcin). Serum was obtained from black bears over a 7-month duration that included periods of activity and inactivity. Both resorption and formation markers increased during hibernation, suggesting high bone turnover occurred during inactivity. However, bone formation appeared to be balanced with bone resorption. The serum concentration of parathyroid hormone (PTH) was higher in the hibernation(P=0.35) and post-hibernation (P=0.006) seasons relative to pre-hibernation levels. Serum leptin was lower (P<0.004)post-hibernation relative to pre-hibernation and hibernation periods. Insulin-like growth factor I (IGF-I) decreased (P<0.0001) during hibernation relative to pre-hibernation and reached its highest value during remobilization. There was no difference (P=0.64) in 25-OH vitamin D between the three seasons. Serum osteocalcin (bone formation marker) was significantly correlated with PTH, but not with leptin, IGF-I or 25-OH vitamin D. Osteocalcin and PTH were positively correlated when samples from all seasons were pooled and when only hibernation samples were considered, raising the possibility that the anabolic actions of PTH help maintain bone formation to prevent disuse osteoporosis. Prostaglandin E2 (PGE2)release from MC3T3 osteoblastic cells was significantly affected by treatment with bear serum from different seasons (i.e. hibernation versus active periods). The seasonal changes in PGE2 release showed trends similar to the seasonal changes in serum IGF-I. Since both PGE2 and IGF-I are associated with collagenous bone formation, it is possible that seasonal changes in a circulating factor influence IGF-I levels in vivo in bears and PGE2 release in osteoblastic cells in vitro. The significant decrease in serum leptin following arousal from hibernation may promote bone formation during remobilization, assuming there is a similar decrease in intracerebroventricular leptin. These findings support the idea that seasonal changes in the concentration of circulating molecules help regulate bone formation activity and may be important for preventing disuse osteoporosis in bears.
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Affiliation(s)
- Seth W Donahue
- Michigan Technological University, 1400 Townsend Drive, Houghton, 49931, USA.
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