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Turner ME, Beck L, Hill Gallant KM, Chen Y, Moe OW, Kuro-o M, Moe S, Aikawa E. Phosphate in Cardiovascular Disease: From New Insights Into Molecular Mechanisms to Clinical Implications. Arterioscler Thromb Vasc Biol 2024; 44:584-602. [PMID: 38205639 PMCID: PMC10922848 DOI: 10.1161/atvbaha.123.319198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
Hyperphosphatemia is a common feature in patients with impaired kidney function and is associated with increased risk of cardiovascular disease. This phenomenon extends to the general population, whereby elevations of serum phosphate within the normal range increase risk; however, the mechanism by which this occurs is multifaceted, and many aspects are poorly understood. Less than 1% of total body phosphate is found in the circulation and extracellular space, and its regulation involves multiple organ cross talk and hormones to coordinate absorption from the small intestine and excretion by the kidneys. For phosphate to be regulated, it must be sensed. While mostly enigmatic, various phosphate sensors have been elucidated in recent years. Phosphate in the circulation can be buffered, either through regulated exchange between extracellular and cellular spaces or through chelation by circulating proteins (ie, fetuin-A) to form calciprotein particles, which in themselves serve a function for bulk mineral transport and signaling. Either through direct signaling or through mediators like hormones, calciprotein particles, or calcifying extracellular vesicles, phosphate can induce various cardiovascular disease pathologies: most notably, ectopic cardiovascular calcification but also left ventricular hypertrophy, as well as bone and kidney diseases, which then propagate phosphate dysregulation further. Therapies targeting phosphate have mostly focused on intestinal binding, of which appreciation and understanding of paracellular transport has greatly advanced the field. However, pharmacotherapies that target cardiovascular consequences of phosphate directly, such as vascular calcification, are still an area of great unmet medical need.
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Affiliation(s)
- Mandy E. Turner
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Laurent Beck
- Nantes Université, CNRS, Inserm, l’institut du thorax, F-44000 Nantes, France
| | - Kathleen M Hill Gallant
- Department of Food Science and Nutrition, University of Minnesota, St. Paul, Minnesota, USA
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Yabing Chen
- Department of Pathology, University of Alabama at Birmingham
- Research Department, Veterans Affairs Birmingham Medical Center, Birmingham, AL, USA
| | - Orson W Moe
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Makoto Kuro-o
- Division of Anti-aging Medicine, Center for Molecular Medicine, Jichi Medical University 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
| | - Sharon Moe
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Elena Aikawa
- Division of Cardiovascular Medicine, Department of Medicine, Center for Interdisciplinary Cardiovascular Sciences, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
- Division of Cardiovascular Medicine, Department of Medicine, Center for Excellence in Vascular Biology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
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Bolamperti S, Villa I, Rubinacci A. Bone remodeling: an operational process ensuring survival and bone mechanical competence. Bone Res 2022; 10:48. [PMID: 35851054 PMCID: PMC9293977 DOI: 10.1038/s41413-022-00219-8] [Citation(s) in RCA: 98] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 05/02/2022] [Accepted: 05/15/2022] [Indexed: 12/12/2022] Open
Abstract
Bone remodeling replaces old and damaged bone with new bone through a sequence of cellular events occurring on the same surface without any change in bone shape. It was initially thought that the basic multicellular unit (BMU) responsible for bone remodeling consists of osteoclasts and osteoblasts functioning through a hierarchical sequence of events organized into distinct stages. However, recent discoveries have indicated that all bone cells participate in BMU formation by interacting both simultaneously and at different differentiation stages with their progenitors, other cells, and bone matrix constituents. Therefore, bone remodeling is currently considered a physiological outcome of continuous cellular operational processes optimized to confer a survival advantage. Bone remodeling defines the primary activities that BMUs need to perform to renew successfully bone structural units. Hence, this review summarizes the current understanding of bone remodeling and future research directions with the aim of providing a clinically relevant biological background with which to identify targets for therapeutic strategies in osteoporosis.
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Affiliation(s)
- Simona Bolamperti
- Osteoporosis and Bone and Mineral Metabolism Unit, IRCCS San Raffaele Hospital, Via Olgettina 60, 20132, Milano, Italy
| | - Isabella Villa
- Osteoporosis and Bone and Mineral Metabolism Unit, IRCCS San Raffaele Hospital, Via Olgettina 60, 20132, Milano, Italy
| | - Alessandro Rubinacci
- Osteoporosis and Bone and Mineral Metabolism Unit, IRCCS San Raffaele Hospital, Via Olgettina 60, 20132, Milano, Italy.
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Zhang Z, Du W, Liu W, Wong BT, Zheng H. Increasing serotonin concentrations alter calcium metabolism in periparturient dairy goats. J Anim Sci 2022; 100:6541332. [PMID: 35235945 PMCID: PMC9030229 DOI: 10.1093/jas/skac065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
Due to the large amounts of calcium transferred to milk from mammary glands, periparturient dairy goats face challenges with calcium metabolism disorder and hypocalcemia. Serotonin (5-hydroxytryptamine, 5-HT), the product of 5-hydroxy-l-tryptophan (5-HTP) catalyzed by tryptophan hydroxylase 1, is a multifunctional monoamine thought to be a homeostatic regulator of the animal. The objective of the current study was to investigate the effects and underlying mechanisms of intramuscular 5-HTP injections on calcium homeostasis in the goat mammary glands. In the in vivo experiment, 30 multiparous Guanzhong dairy goats were randomly assigned to 2 groups, one group was injected with 5-HTP intramuscularly and the other group was injected with normal saline. From the first 10 d of the expected date for delivery, 5-HTP or saline was injected into goats through the shoulder muscle every morning before feeding, with a dose of 1 mg/kg per body weight. In the in vitro experiment, goat mammary epithelial cells (GMEC) were treated with 100 μM 5-HT for the evaluation of 5-HT in calcium transportation. The results demonstrated that 5-HTP treatment had no effect on the basic composition of colostrum (P > 0.05) but increased the serum 5-HT concentrations on days -5, -4, -3, and 5 relative to parturition (P < 0.05). The 5-HTP injection group had greater serum calcium concentration on day 4 and greater serum parathyroid hormone-related protein (PTHrP) on days -5, -4, -1, 3, 4, and 5 compared with the saline injection group (P < 0.05). It was further confirmed that 5-HT could increase intracellular calcium levels by increasing PTHrP and decreasing plasma membrane Ca2+-ATPases1 (PMCA1) in GMEC (P < 0.05). In conclusion, 5-HTP treatment in multiparous goats during the transition period from pregnancy to lactation is a feasible way to protect goats from calcium metabolism disorder.
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Affiliation(s)
- ZhiFei Zhang
- Laboratory of Genetic Improvement and Healthy Breeding of Dairy Goats, Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, People’s Republic of China
| | - Wei Du
- Laboratory of Genetic Improvement and Healthy Breeding of Dairy Goats, Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, People’s Republic of China
| | - WenYi Liu
- Laboratory of Genetic Improvement and Healthy Breeding of Dairy Goats, Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, People’s Republic of China
| | - Braden T Wong
- Department of Animal Science, University of California, Davis, CA 95616, USA
| | - HuiLing Zheng
- Laboratory of Genetic Improvement and Healthy Breeding of Dairy Goats, Shaanxi Key Laboratory of Molecular Biology for Agriculture, College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi 712100, People’s Republic of China,Corresponding author:
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Roberts WE, Mangum JE, Schneider PM. Pathophysiology of Demineralization, Part I: Attrition, Erosion, Abfraction, and Noncarious Cervical Lesions. Curr Osteoporos Rep 2022; 20:90-105. [PMID: 35129809 PMCID: PMC8930910 DOI: 10.1007/s11914-022-00722-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/15/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE OF THE REVIEW Compare pathophysiology for infectious and noninfectious demineralization disease relative to mineral maintenance, physiologic fluoride levels, and mechanical degradation. RECENT FINDINGS Environmental acidity, biomechanics, and intercrystalline percolation of endemic fluoride regulate resistance to demineralization relative to osteopenia, noncarious cervical lesions, and dental caries. Demineralization is the most prevalent chronic disease in the world: osteoporosis (OP) >10%, dental caries ~100%. OP is severely debilitating while caries is potentially fatal. Mineralized tissues have a common physiology: cell-mediated apposition, protein matrix, fluid logistics (blood, saliva), intercrystalline ion percolation, cyclic demineralization/remineralization, and acid-based degradation (microbes, clastic cells). Etiology of demineralization involves fluid percolation, metabolism, homeostasis, biomechanics, mechanical wear (attrition or abrasion), and biofilm-related infections. Bone mineral density measurement assesses skeletal mass. Attrition, abrasion, erosion, and abfraction are diagnosed visually, but invisible subsurface caries <400μm cannot be detected. Controlling demineralization at all levels is an important horizon for cost-effective wellness worldwide.
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Affiliation(s)
- W. Eugene Roberts
- grid.257413.60000 0001 2287 3919Indiana University & Purdue University at Indianapolis, 8260 Skipjack Drive, Indianapolis, IN 46236 USA
| | - Jonathan E. Mangum
- grid.1008.90000 0001 2179 088XDepartment of Biochemistry and Pharmacology, Dentistry and Health Sciences, University of Melbourne, Corner Grattan Street and Royal Parade, Parkville, Victoria 3010 Australia
| | - Paul M. Schneider
- grid.1008.90000 0001 2179 088XMelbourne Dental School, University of Melbourne, 720 Swanston St, Melbourne, Victoria 3010 Australia
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Abstract
It has previously been reported that in ex vivo planar explants prepared from Xenopus laevis embryos, the intracellular pH (pHi) increases in cells of the dorsal ectoderm from stage 10.5 to 11.5 (i.e. 11-12.5 hpf). It was proposed that such increases (potentially due to H+ being extruded, sequestered, or buffered in some manner), play a role in regulating neural induction. Here, we used an extracellular ion-selective electrode to non-invasively measure H+ fluxes at eight locations around the equatorial circumference of intact X. laevis embryos between stages 9-12 (˜7-13.25 hpf). We showed that at stages 9-11, there was a small H+ efflux recorded from all the measuring positions. At stage 12 there was a small, but significant, increase in the efflux of H+ from most locations, but the efflux from the dorsal side of the embryo was significantly greater than from the other positions. Embryos were also treated from stages 9-12 with bafilomycin A1, to block the activity of the ATP-driven H+ pump. By stage 22 (24 hpf), these embryos displayed retarded development, arresting before the end of gastrulation and therefore did not display the usual anterior and neural structures, which were observed in the solvent-control embryos. In addition, expression of the early neural gene, Zic3, was absent in treated embryos compared with the solvent controls. Together, our new in vivo data corroborated and extended the earlier explant-derived report describing changes in pHi that were suggested to play a role during neural induction in X. laevis embryos.
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Poorhemati H, Komarova SV. Mathematical modeling of the role of bone turnover in pH regulation in bone interstitial fluid. Comput Biol Chem 2021; 94:107564. [PMID: 34455167 DOI: 10.1016/j.compbiolchem.2021.107564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 07/20/2021] [Accepted: 08/15/2021] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND AIMS Bone turnover is strongly affected by pH of surrounding fluid, and in turn plays a role in maintaining systemic pH, however the quantitative contribution of bone processes to pH regulation is not known. Our goal was to develop a mathematical model describing pH regulation in the interstitial fluid and to examine the contribution of hydroxyapatite dissolution and precipitation to pH regulation. MATERIALS AND METHODS We modeled twelve reversible equilibrium reactions of sixteen calcium, phosphate, hydrogen and carbonate species in the interstitial fluid and examined the buffering capacity and range. The effect of hydroxyapatite dissolution and precipitation was modeled by assuming that the calcium, phosphate and hydroxide contained in the bone volume adjacent to the interstitial fluid is instantaneously added to or removed from the interstitial fluid. RESULTS The carbonate buffer was found to dominate electrochemical buffering system of the bone interstitial fluid. Nevertheless, the phosphate added during dissolution of bone hydroxyapatite significantly improved the interstitial fluid buffering capacity. In contrast, hydroxyapatite precipitation had limited effect on the interstitial fluid pH regulation. CONCLUSION This study provides mechanistic insights into the physicochemical processes underlying the known role of bone turnover processes in regulation of body pH homeostasis.
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Affiliation(s)
- Hossein Poorhemati
- Department of Biological and Biomedical Engineering, McGill University, Montreal, QC, Canada; Shriners Hospital for Children - Canada, Montreal, QC, Canada.
| | - Svetlana V Komarova
- Department of Biological and Biomedical Engineering, McGill University, Montreal, QC, Canada; Shriners Hospital for Children - Canada, Montreal, QC, Canada; Faculty of Dentistry, McGill University, Montreal, QC, Canada.
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7
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CRISPR/Cas9-mediated tryptophan hydroxylase 1 knockout decreases calcium transportation in goat mammary epithelial cells. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Jamieson L, Waters A, Ho KE, Chan HYS, Hung JT, Webb SE, Chan CM, Shipley AM, Williamson JG, Beer J, Angus C, Miller AL. Short-term homeostatic regulation of blood/interstitial fluid Ca 2+ concentration by the scales of anadromous sea trout Salmo trutta L. during smoltification and migration. JOURNAL OF FISH BIOLOGY 2021; 98:17-32. [PMID: 32964432 DOI: 10.1111/jfb.14553] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/20/2020] [Indexed: 06/11/2023]
Abstract
The elasmoid scales of anadromous sea trout Salmo trutta L. represent a significant internal reservoir of Ca2+ . Although more is known about long-term remodelling of scales in response to calciotropic challenges encountered during smoltification and migration, very little is known about the contribution made by scales to the short-term, minute-to-minute regulation of Ca2+ homeostasis in the extracellular fluid (ECF) during these phases of the life cycle. This gap in the knowledge is partly due to the technical challenges involved in measuring small Ca2+ fluxes around the scales of live fish in real time. Here, this study describes exfoliating, mounting and culturing scales and their resident cells from parr, smolt and adult sea trout from a freshwater environment, as well as from adult sea trout caught in sea or brackish water. All the scales were then examined using an extracellular, non-invasive, surface-scanning Ca2+ -sensitive microelectrode. The authors quantified the Ca2+ fluxes, in the absence of any systemic or local regulators, into and out of scales on both the episquamal and hyposquamal sides under different extracellular calcemic challenges set to mimic a variety of ECF-Ca2+ concentrations. Scales from the life-cycle stages as well as from adult fish taken from sea, brackish or fresh water all showed a consistent efflux or influx of Ca2+ under hypo- or hypercalcemic conditions, respectively. What were considered to be isocalcemic conditions resulted in minimal flux of Ca2+ in either direction, or in the case of adult scales, a consistent but small influx. Indeed, adult scales appeared to display the largest flux densities in either direction. These new data extend the current understanding of the role played by fish scales in the short-term, minute-to-minute homeostatic regulation of ECF-Ca2+ concentration, and are similar to those recently reported from zebrafish Danio rerio scales. This suggests that this short-term regulatory response might be a common feature of teleost scales.
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Affiliation(s)
- Leanna Jamieson
- North Atlantic Fisheries College Marine Centre, University of the Highlands and Islands, Scalloway, UK
| | - Angel Waters
- College of Arts and Sciences, University of New England, Biddeford, Maine, USA
| | - Kaitlyn E Ho
- Division of Life Science and State Key Laboratory for Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Harvey Y S Chan
- Division of Life Science and State Key Laboratory for Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Jacky T Hung
- Division of Life Science and State Key Laboratory for Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Sarah E Webb
- Division of Life Science and State Key Laboratory for Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Ching Man Chan
- Division of Life Science and State Key Laboratory for Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Alan M Shipley
- Applicable Electronics, LLC, New Haven, Connecticut, USA
| | | | - Jon Beer
- The Wild Trout Trust, Hampshire, UK
| | - Chevonne Angus
- North Atlantic Fisheries College Marine Centre, University of the Highlands and Islands, Scalloway, UK
| | - Andrew L Miller
- Division of Life Science and State Key Laboratory for Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
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Li D, Guo B, Liang Q, Liu Y, Zhang L, Hu N, Zhang X, Yang F, Ruan C. Tissue-engineered parathyroid gland and its regulatory secretion of parathyroid hormone. J Tissue Eng Regen Med 2020; 14:1363-1377. [PMID: 32511868 DOI: 10.1002/term.3080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/02/2020] [Accepted: 06/03/2020] [Indexed: 11/11/2022]
Abstract
Parathyroid glands (PTGs) are important endocrine organs being mainly responsible for the secretion of parathyroid hormone (PTH) to regulate the balance of calcium (Ca) /phosphorus (P) ions in the body. Once PTGs get injured or removed, their resulting defect or loss of PTH secretion should disturb the level of Ca/P in blood, thus damaging other related organs (bone, kidney, etc.) and even causing death. Recently, tissue-engineered PTGs (TE-PTGs) have attracted lots of attention as a potential treatment for the related diseases of PTGs caused by hypoparathyroidism and hyperparathyroidism, including tetany, muscle cramp, nephrolithiasis, nephrocalcinosis, and osteoporosis. Although great progress has been made in the establishment of TE-PTGs with an effective strategy to integrate the key factors of cells and biomaterials, its regulatory secretion of PTH to mimic its natural rhythms in the body remains a huge challenge. This review comprehensively describes an overview of PTGs from physiology and pathology to cytobiology and tissue engineering. The state of the arts in TE-PTGs and the feasible strategies to regulate PTH secretion behaviors are highlighted to provide an important foundation for further investigation.
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Affiliation(s)
- Duo Li
- Research Center for Human Tissue and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, PR China.,University of Chinese Academy of Sciences, Beijing, PR China
| | - Baochun Guo
- Department of Nephrology, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, PR China.,Key Laboratory of Shenzhen Renal Diseases, Shenzhen, PR China
| | - Qingfei Liang
- Research Center for Human Tissue and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, PR China.,University of Chinese Academy of Sciences, Beijing, PR China
| | - Yunhui Liu
- University of Chinese Academy of Sciences, Beijing, PR China.,The Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, PR China
| | - Lu Zhang
- The Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, PR China
| | - Nan Hu
- Department of Nephrology, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, PR China.,Key Laboratory of Shenzhen Renal Diseases, Shenzhen, PR China
| | - Xinzhou Zhang
- Department of Nephrology, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University; The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen, PR China.,Key Laboratory of Shenzhen Renal Diseases, Shenzhen, PR China
| | - Fan Yang
- University of Chinese Academy of Sciences, Beijing, PR China.,The Brain Cognition and Brain Disease Institute, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, PR China
| | - Changshun Ruan
- Research Center for Human Tissue and Organs Degeneration, Institute of Biomedicine and Biotechnology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, PR China.,University of Chinese Academy of Sciences, Beijing, PR China
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Abstract
A history of prior fracture is the most reliable indicator of prospective fracture risk. Increased fracture risk is not confined to the region of the prior fracture, but is operant at all skeletal sites, providing strong evidence of systemic bone loss after fracture. Animal and human studies suggest that systemic bone loss begins shortly after fracture and persists for several years in humans. In fact, bone quantity and bone quality may never fully return to their pre-fracture levels, especially in older subjects, demonstrating a need for improved understanding of the mechanisms leading to systemic bone loss after fracture in order to reduce subsequent fracture risk. Although the process remains incompletely understood, mechanical unloading (disuse), systemic inflammation, and hormones that control calcium homeostasis may all contribute to systemic bone loss. Additionally, individual factors can potentially affect the magnitude and time course of systemic bone loss and recovery. The magnitude of systemic bone loss correlates positively with injury severity and age. Men may also experience greater bone loss or less recovery than women after fracture. This review details the current understanding of systemic bone loss following fracture, including possible underlying mechanisms and individual factors that may affect this injury response.
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