201
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Shi M, Maique J, Shaffer J, Davidson T, Sebti S, Fernández ÁF, Zou Z, Yan S, Levine B, Moe OW, Hu MC. The tripartite interaction of phosphate, autophagy, and αKlotho in health maintenance. FASEB J 2020; 34:3129-3150. [PMID: 31908069 PMCID: PMC7286356 DOI: 10.1096/fj.201902127r] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 12/19/2019] [Accepted: 12/19/2019] [Indexed: 12/11/2022]
Abstract
Aging-related organ degeneration is driven by multiple factors including the cell maintenance mechanisms of autophagy, the cytoprotective protein αKlotho, and the lesser known effects of excess phosphate (Pi), or phosphotoxicity. To examine the interplay between Pi, autophagy, and αKlotho, we used the BK/BK mouse (homozygous for mutant Becn1F121A ) with increased autophagic flux, and αKlotho-hypomorphic mouse (kl/kl) with impaired urinary Pi excretion, low autophagy, and premature organ dysfunction. BK/BK mice live longer than WT littermates, and have heightened phosphaturia from downregulation of two key NaPi cotransporters in the kidney. The multi-organ failure in kl/kl mice was rescued in the double-mutant BK/BK;kl/kl mice exhibiting lower plasma Pi, improved weight gain, restored plasma and renal αKlotho levels, decreased pathology of multiple organs, and improved fertility compared to kl/kl mice. The beneficial effects of heightened autophagy from Becn1F121A was abolished by chronic high-Pi diet which also shortened life span in the BK/BK;kl/kl mice. Pi promoted beclin 1 binding to its negative regulator BCL2, which impairs autophagy flux. Pi downregulated αKlotho, which also independently impaired autophagy. In conclusion, Pi, αKlotho, and autophagy interact intricately to affect each other. Both autophagy and αKlotho antagonizes phosphotoxicity. In concert, this tripartite system jointly determines longevity and life span.
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Affiliation(s)
- Mingjun Shi
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jenny Maique
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joy Shaffer
- Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Taylor Davidson
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Salwa Sebti
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Álvaro F. Fernández
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Zhongju Zou
- Center for Autophagy Research, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Shirley Yan
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Beth Levine
- Center for Autophagy 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 Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, 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
| | - Ming Chang Hu
- 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
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202
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Bauvois A, Larivière M, Watier H, Maillot F. [Monoclonal antibodies for monogenic diseases: a 2019 update]. Med Sci (Paris) 2020; 35:1026-1028. [PMID: 31903913 DOI: 10.1051/medsci/2019203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Monogenic diseases are rare genetic diseases but they are numerous and display a highly variable degree of severity. First uses of monoclonal antibodies to treat monogenic diseases started in the 2000's and many clinical trials are ongoing. Anti-IL-1β therapies have greatly modified the outcome of auto-inflammatory diseases by modulating inflammatory response and reducing the risk of secondary amyloidosis. Anti-TNF-α are also used in such diseases. In atypical hemolytic and uremic syndrome due to deficiencies in the control of alternative complement pathway, eculizumab, an anti-C5 monoclonal antibody, has improved renal outcome in treated patients. More recently, lanadelumab, an anti-plasma kallikrein antibody, has reinforced the therapeutic arsenal in hereditary angioedema and burosumab, anti-FGF23, that of X-linked hypophosphatemia. Such examples reflect the importance of monoclonal antibody therapy of monogenic diseases, the interest of considering such an option as well as the need for future researches.
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Affiliation(s)
| | | | - Hervé Watier
- CHRU de Tours, Laboratoire d'Immunologie;, - Université de Tours, France
| | - François Maillot
- CHRU de Tours, Service de Médecine interne;, - Université de Tours, France
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203
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Chang Y, Kim J, Woo HG, Ryu DR, Oh HJ, Song TJ. Plasma Fibroblast Growth Factor 23 Concentration Is Associated with Intracranial Cerebral Atherosclerosis in Acute Ischemic Stroke Patients. J Clin Neurol 2020; 16:29-36. [PMID: 31942755 PMCID: PMC6974828 DOI: 10.3988/jcn.2020.16.1.29] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 08/21/2019] [Accepted: 08/21/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND AND PURPOSE Fibroblast growth factor 23 (FGF23) is associated with atherosclerosis via nitric-oxide-associated endothelial dysfunction and calcium-phosphate-related bone mineralization. This study aimed to determine the association of the plasma FGF23 concentration with intracranial cerebral atherosclerosis (ICAS) and extracranial cerebral atherosclerosis (ECAS). METHODS We prospectively enrolled 262 first-ever ischemic stroke patients in whom brain magnetic resonance was performed and a blood sample acquired within 24 h after admission. Plasma FGF23 concentrations were measured using an enzyme-linked immunosorbent assay. The presence of ICAS or ECAS was defined as a ≥50% decrease in arterial diameter in magnetic resonance angiography. The burden of cerebral atherosclerosis was calculated by adding the total number of vessels defined as ICAS or ECAS. RESULTS Our study population included 152 (58.0%) males. The mean age was 64.7 years, and the plasma FGF23 concentration was 347.5±549.6 pg/mL (mean±SD). ICAS only, ECAS only, and both ICAS and ECAS were present in 31.2% (n=82), 4.9% (n=13), and 6.8% (n=18) of the subjects, respectively. In multivariate binary and ordinal logistic analyses, after adjusting for sex, age, and variables for which p<0.1 in the univariate analysis, the plasma FGF23 concentration (per 100 pg/mL) was positively correlated with the presence of ICAS [odds ratio (OR)=1.07, 95% CI=1.00-1.15, p=0.039], burden of ICAS (OR=1.09, 95% CI=1.04-1.15, p=0.001), and burden of ECAS (OR=1.06, 95% CI=1.00-1.12, p=0.038), but it was not significantly related to the presence of ECAS (OR=1.05, 95% CI=0.99-1.12, p=0.073). CONCLUSIONS The plasma FGF23 may be a potential biomarker for cerebral atherosclerosis, particularly the presence and burden of ICAS in stroke patients.
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Affiliation(s)
- Yoonkyung Chang
- Department of Neurology, Ewha Womans University Mokdong Hospital, Ewha Womans University College of Medicine, Seoul, Korea
| | - Jinkwon Kim
- Department of Neurology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Ho Geol Woo
- Department of Neurology, Ewha Womans University Seoul Hospital, Ewha Womans University College of Medicine, Seoul, Korea
| | - Dong Ryeol Ryu
- Department of Internal Medicine, Ewha Womans University College of Medicine, Seoul, Korea
| | - Hyung Jung Oh
- Ewha Institute of Convergence Medicine, Ewha Womans University Mokdong Hospital, Seoul, Korea
| | - Tae Jin Song
- Department of Neurology, Ewha Womans University Mokdong Hospital, Ewha Womans University College of Medicine, Seoul, Korea.
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204
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Saraff V, Nadar R, Högler W. New Developments in the Treatment of X-Linked Hypophosphataemia: Implications for Clinical Management. Paediatr Drugs 2020; 22:113-121. [PMID: 31965544 PMCID: PMC7083817 DOI: 10.1007/s40272-020-00381-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
X-linked hypophosphataemia (XLH) is due to mutations in phosphate-regulating gene with homologies to endopeptidases on the X chromosome (PHEX) and represents the most common heritable form of rickets. In this condition, the hormone fibroblast growth factor 23 (FGF23) is produced in excessive amounts for still unknown reasons, and causes renal phosphate wasting and suppression of 1,25-dihydroxyvitamin D, leading to low serum phosphate concentrations. Prolonged hypophosphataemia decreases apoptosis of hypertrophic chondrocytes in growth plates (causing rickets) and decreases mineralisation of existing bone (causing osteomalacia). In contrast to historical conventional treatment with oral phosphate supplements and active vitamin D for the last 50 years, the new anti-FGF23 antibody treatment (burosumab) targets the primary pathology by blocking FGF23, thereby restoring phosphate homeostasis. In this review, we describe the changes in treatment monitoring, treatment targets and long-term treatment goals, including future opportunities and challenges in the treatment of XLH in children.
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Affiliation(s)
- Vrinda Saraff
- Department of Endocrinology and Diabetes, Birmingham Women’s and Children’s Hospital NHS Trust, Birmingham, UK ,grid.6572.60000 0004 1936 7486Institute of Applied Health Research, University of Birmingham, Birmingham, UK
| | - Ruchi Nadar
- Department of Endocrinology and Diabetes, Birmingham Women’s and Children’s Hospital NHS Trust, Birmingham, UK
| | - Wolfgang Högler
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK. .,Department of Pediatrics and Adolescent Medicine, Johannes Kepler University Linz, Kepler Universitätsklinikum, Krankenhausstrasse 26-30, 4020, Linz, Austria.
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205
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Gao X, Zhu M, An S, Liang Y, Yang H, Pang J, Liu Z, Zhang G, Wang F. Long non-coding RNA LOC105611671 modulates fibroblast growth factor 9 (FGF9) expression by targeting oar-miR-26a to promote testosterone biosynthesis in Hu sheep. Reprod Fertil Dev 2020; 32:373-382. [DOI: 10.1071/rd19116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 07/15/2019] [Indexed: 12/12/2022] Open
Abstract
Fibroblast growth factors (FGFs) play crucial roles in early gonadal development and germ cell maturation of mammals; FGF9 is involved in mammalian testis steroidogenesis. However, the upstream regulators of FGF9 in ovine testosterone biosynthesis remain unknown. Long non-coding RNAs (lncRNAs) are crucial regulators of multiple biological functions that act by altering gene expression. In the present study, we analysed the role of LOC105611671, a lncRNA upstream of FGF9, in Hu sheep steroidogenesis. We found that LOC105611671 expression increased significantly in Hu sheep testes during sexual maturation (P<0.05). Moreover, levels of FGF9 and testosterone were decreased by LOC105611671 knockdown in Hu sheep Leydig cells (LCs). Results of transient transfection and luciferase assays revealed that FGF9 is a functional target gene of oar-miR-26a in ovine LCs. Further functional validation experiments revealed that LOC105611671 regulates testosterone biosynthesis by targeting oar-miR-26a. Overall, the present study describes the expression profile of LOC105611671 during sexual maturation and demonstrates that LOC105611671 modulates FGF9 expression by targeting oar-miR-26a to promote testis steroidogenesis in Hu sheep. Our research provides a new theoretical basis for genetic and molecular research on testosterone biosynthesis in sheep.
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206
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Fukumoto S, Takashi Y, Tsoumpra MK, Sawatsubashi S, Matsumoto T. How do we sense phosphate to regulate serum phosphate level? J Bone Miner Metab 2020; 38:1-6. [PMID: 31797064 DOI: 10.1007/s00774-019-01066-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 11/05/2019] [Indexed: 12/25/2022]
Abstract
Abnormal phosphate levels result in several pathological conditions such as rickets/osteomalacia and ectopic calcification indicating that there must be a system that regulates phosphate level within a narrow range. FGF23 has been shown to be an essential hormone regulating serum phosphate level. FGF23 binds to Klotho-FGF receptor complex to reduce serum phosphate level. Several reports suggested that FGF receptor is involved in the regulation of FGF23 production. It has been also shown that high extracellular phosphate can activate several intracellular signaling pathways. However, it has been unclear whether and how phosphate regulates FGF23 production in vivo. Our recent results indicate that high extracellular phosphate directly activates FGF receptor 1 and the downstream intracellular signaling enhances FGF23 production. Thus, there is a negative feedback system for the regulation of serum phosphate level involving FGF receptor and FGF23. We propose that FGF receptor works at least as one of phosphate sensors in the maintenance of serum phosphate level.
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Affiliation(s)
- Seiji Fukumoto
- Department of Molecular Endocrinology, Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan.
| | - Yuichi Takashi
- Department of Molecular Endocrinology, Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan
- Department of Endocrinology and Diabetes Mellitus, Fukuoka University Chikushi Hospital, 1-1-1 Zokumyoin, Chikushino, 818-8502, Japan
| | - Maria K Tsoumpra
- Department of Molecular Endocrinology, Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan
- Department of Molecular Therapy, National Institute of Neuroscience, National Center for Neurology and Psychiatry, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo, 187-8502, Japan
| | - Shun Sawatsubashi
- Department of Molecular Endocrinology, Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan
| | - Toshio Matsumoto
- Department of Molecular Endocrinology, Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, Tokushima, 770-8503, Japan
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207
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Abstract
Bone and mineral diseases encompass a variety of conditions that involve altered skeletal homeostasis and are frequently associated with changes in circulating calcium, phosphate, or vitamin D metabolites. These disorders often have a genetic etiology and comprise monogenic disorders caused by a single-gene mutation, which may be germline or somatic, or an oligogenic or polygenic condition involving multiple genetic variants. Single-gene mutations causing Mendelian diseases are usually highly penetrant, whereas the gene variants contributing to oligogenic or polygenic disorders are each associated with smaller effects with additional contributions from environmental factors. The detection of monogenic disorders is clinically important and facilitates timely assessment and management of the patient and their affected relatives. The diagnosis of monogenic metabolic bone disorders requires detailed clinical assessment of the wide variety of symptoms and signs associated with these diseases. Thus, clinicians should undertake a systematic approach commencing with careful history taking and physical examination, followed by appropriate laboratory and skeletal imaging investigations. Finally, clinicians should be familiar with the range of molecular genetic tests available to ensure their appropriate use and interpretation. These considerations are reviewed in this chapter.
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208
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Schindeler A, Biggin A, Munns CF. Clinical Evidence for the Benefits of Burosumab Therapy for X-Linked Hypophosphatemia (XLH) and Other Conditions in Adults and Children. Front Endocrinol (Lausanne) 2020; 11:338. [PMID: 32547492 PMCID: PMC7271822 DOI: 10.3389/fendo.2020.00338] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 04/29/2020] [Indexed: 12/14/2022] Open
Abstract
Burosumab (KRN23) is an FGF23 neutralizing antibody that has been the subject of several recent clinical trials principally focused on the treatment of hypophosphatemic rickets in patients with X-linked hypophosphatemia (XLH). Since the first publications in 2014, these trials have demonstrated efficacy with minimal safety concerns in both adult and pediatric cohorts. These studies have used dose-escalation to establish a dosing regimen that is well-tolerated in clinical use. This review summarizes the clinical trial data with respect to burosumab treatment in adults and children as well as noting several clinical trials currently underway. While burosumab appears transformative for the treatment of XLH, long term follow-up studies would be required to allay concerns over the potential for nephrocalcinosis and cardiac calcification. While these do not appear to be problematic in current trials, the effects of chronic or lifelong treatment have yet to be established.
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Affiliation(s)
- Aaron Schindeler
- Bioengineering and Molecular Medicine Laboratory, The Children's Hospital at Westmead, Westmead, NSW, Australia
- Discipline of Child and Adolescent Health, University of Sydney, Sydney, NSW, Australia
| | - Andrew Biggin
- Discipline of Child and Adolescent Health, University of Sydney, Sydney, NSW, Australia
- Department of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - Craig F. Munns
- Discipline of Child and Adolescent Health, University of Sydney, Sydney, NSW, Australia
- Department of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead, NSW, Australia
- *Correspondence: Craig F. Munns
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209
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Matthias J, Cui Q, Shumate LT, Plagge A, He Q, Bastepe M. Extra-Large Gα Protein (XLαs) Deficiency Causes Severe Adenine-Induced Renal Injury with Massive FGF23 Elevation. Endocrinology 2020; 161:5638044. [PMID: 31758181 PMCID: PMC6986553 DOI: 10.1210/endocr/bqz025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 11/22/2019] [Indexed: 11/19/2022]
Abstract
Fibroblast growth factor-23 (FGF23) is critical for phosphate and vitamin D homeostasis. Cellular and molecular mechanisms underlying FGF23 production remain poorly defined. The extra-large Gα subunit (XLαs) is a variant of the stimulatory G protein alpha-subunit (Gsα), which mediates the stimulatory action of parathyroid hormone in skeletal FGF23 production. XLαs ablation causes diminished FGF23 levels in early postnatal mice. Herein we found that plasma FGF23 levels were comparable in adult XLαs knockout (XLKO) and wild-type littermates. Upon adenine-rich diet-induced renal injury, a model of chronic kidney disease, both mice showed increased levels of plasma FGF23. Unexpectedly, XLKO mice had markedly higher FGF23 levels than WT mice, with higher blood urea nitrogen and more severe tubulopathy. FGF23 mRNA levels increased substantially in bone and bone marrow in both genotypes; however, the levels in bone were markedly higher than in bone marrow. In XLKO mice, a positive linear correlation was observed between plasma FGF23 and bone, but not bone marrow, FGF23 mRNA levels, suggesting that bone, rather than bone marrow, is an important contributor to severely elevated FGF23 levels in this model. Upon folic acid injection, a model of acute kidney injury, XLKO and WT mice exhibited similar degrees of tubulopathy; however, plasma phosphate and FGF23 elevations were modestly blunted in XLKO males, but not in females, compared to WT counterparts. Our findings suggest that XLαs ablation does not substantially alter FGF23 production in adult mice but increases susceptibility to adenine-induced kidney injury, causing severe FGF23 elevations in plasma and bone.
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Affiliation(s)
- Julia Matthias
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Qiuxia Cui
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
- Department of Thyroid and Breast Surgery, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Lauren T Shumate
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
| | - Antonius Plagge
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, UK
| | - Qing He
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
- Correspondence: Murat Bastepe, MD, PhD, 50 Blossom St. Thier 10 Boston, MA 02114, USA. E-mail: and Qing He, PhD 50 Blossom St. Thier 10 Boston, Massachusetts 02114, USA. E-mail:
| | - Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
- Correspondence: Murat Bastepe, MD, PhD, 50 Blossom St. Thier 10 Boston, MA 02114, USA. E-mail: and Qing He, PhD 50 Blossom St. Thier 10 Boston, Massachusetts 02114, USA. E-mail:
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210
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Ren Z, Piepenburg AJ, Yang X, Cook ME. Effect of anti-fibroblast growth factor 23 antibody on phosphate and calcium metabolism in adenine gavaged laying hens. Poult Sci 2019; 98:4896-4900. [PMID: 31064011 DOI: 10.3382/ps/pez239] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 04/30/2019] [Indexed: 01/26/2023] Open
Abstract
Dietary factors such as adenine have been linked to phosphate-calcium metabolism disturbance and adverse productive outcomes. Anti-fibroblast growth factor 23 (FGF-23) antibody has been proposed to ameliorate adenine-induced abnormal FGF23/phosphate metabolism. This experiment was conducted to investigate the application of anti-FGF-23 antibody in adenine-gavaged laying hens. Single Comb White Leghorn laying hens with (n = 10) or without (control group, n = 10) systemic anti-FGF-23 antibody were orally gavaged with adenine (600 mg/hen/D) for 21 consecutive days. Adenine gavage increased (P ≤ 0.01) plasma phosphate and calcium levels and tended to increase (0.05 < P ≤ 0.1) plasma 1,25-dihydroxy-cholecalciferol [1,25(OH)2D3] level of hens without FGF-23 antibody. In hen with anti-FGF-23 antibody, adenine gavage increased (P ≤ 0.01) body weight and plasma calcium level and decreased (P ≤ 0.05) plasma FGF-23 level. Feed intake of hens in both treatments was suddenly decreased (control hens decreased from 111 to 55 g, P ≤ 0.01; anti-FGF-23 hens decreased from 96 to 46 g, P ≤ 0.01) 10 D after adenine gavage. Anti-FGF-23 antibody tended to increase (0.05 < P ≤ 0.1) plasma phosphorus level of hens before adenine gavage, interestingly, and decreased (P ≤ 0.01) plasma FGF-23 level and kidney index (% of body weight) of hens after adenine gavage. In conclusion, anti-FGF-23 antibody might be used (before or in the early stage) to delay the development of adenine-induced abnormal FGF23/phosphate metabolism. This is the first study to investigate the FGF-23 status in chickens suffering from dietary factors which may cause abnormal renal phosphate resorption.
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Affiliation(s)
- Zhouzheng Ren
- College of Animal Science and Technology, Northwest A&F University, 22 XiNong Road, Yangling, Shaanxi 712100, China.,Department of Animal Sciences, University of Wisconsin-Madison, 1675 Observatory Drive, Madison, WI 53706, USA
| | - Alexis J Piepenburg
- Department of Animal Sciences, University of Wisconsin-Madison, 1675 Observatory Drive, Madison, WI 53706, USA
| | - Xiaojun Yang
- College of Animal Science and Technology, Northwest A&F University, 22 XiNong Road, Yangling, Shaanxi 712100, China
| | - Mark E Cook
- Department of Animal Sciences, University of Wisconsin-Madison, 1675 Observatory Drive, Madison, WI 53706, USA
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211
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Abstract
Fibroblast growth factor 23 (FGF23) is a hormone with a central role in the regulation of phosphate homeostasis. This regulation is accomplished by the coordinated modulation of renal phosphate handling, vitamin D metabolism and parathyroid hormone secretion. Patients with kidney disease have increased circulating levels of FGF23 and in other patient populations and in healthy individuals, FGF23 levels also rise following an increase in dietary phosphate intake. Maladaptive increases in FGF23 have a detrimental effect on several organs and tissues and, importantly, these pathological changes most likely contribute to increased morbidity and mortality. For example, in the context of heart disease, FGF23 is involved in the development of pathological hypertrophy that can lead to congestive heart failure. Increased FGF23 concentrations can also lead to microcirculatory changes, in particular reduced vasodilatory capacity, and collectively these cardiovascular changes can compromise tissue perfusion. In addition, FGF23 is associated with inflammation and an increased risk of infection; other potentially detrimental effects of FGF23 are likely to emerge in the future. Most importantly, recent insights demonstrate that FGF23 can be therapeutically targeted, which holds promise for the treatment of many patients in a variety of clinical settings.
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212
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Abstract
The Klotho proteins, αKlotho and βKlotho, are essential components of endocrine fibroblast growth factor (FGF) receptor complexes, as they are required for the high-affinity binding of FGF19, FGF21 and FGF23 to their cognate FGF receptors (FGFRs). Collectively, these proteins form a unique endocrine system that governs multiple metabolic processes in mammals. FGF19 is a satiety hormone that is secreted from the intestine on ingestion of food and binds the βKlotho-FGFR4 complex in hepatocytes to promote metabolic responses to feeding. By contrast, under fasting conditions, the liver secretes the starvation hormone FGF21, which induces metabolic responses to fasting and stress responses through the activation of the hypothalamus-pituitary-adrenal axis and the sympathetic nervous system following binding to the βKlotho-FGFR1c complex in adipocytes and the suprachiasmatic nucleus, respectively. Finally, FGF23 is secreted by osteocytes in response to phosphate intake and binds to αKlotho-FGFR complexes, which are expressed most abundantly in renal tubules, to regulate mineral metabolism. Growing evidence suggests that the FGF-Klotho endocrine system also has a crucial role in the pathophysiology of ageing-related disorders, including diabetes, cancer, arteriosclerosis and chronic kidney disease. Therefore, targeting the FGF-Klotho endocrine axes might have therapeutic benefit in multiple systems; investigation of the crystal structures of FGF-Klotho-FGFR complexes is paving the way for the development of drugs that can regulate these axes.
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Affiliation(s)
- Makoto Kuro-O
- Division of Anti-aging Medicine, Center for Molecular Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan. .,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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213
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Michigami T. Skeletal mineralization: mechanisms and diseases. Ann Pediatr Endocrinol Metab 2019; 24:213-219. [PMID: 31905439 PMCID: PMC6944863 DOI: 10.6065/apem.2019.24.4.213] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/20/2019] [Indexed: 12/22/2022] Open
Abstract
Skeletal mineralization is initiated in matrix vesicles (MVs), the small extracellular vesicles derived from osteoblasts and chondrocytes. Calcium and inorganic phosphate (Pi) taken up by MVs form hydroxyapatite crystals, which propagate on collagen fibrils to mineralize the extracellular matrix. Insufficient calcium or phosphate impairs skeletal mineralization. Because active vitamin D is necessary for intestinal calcium absorption, vitamin D deficiency is a significant cause of rickets/osteomalacia. Chronic hypophosphatemia also results in rickets/osteomalacia. Excessive action of fibroblast growth factor 23 (FGF23), a key regulator of Pi metabolism, leads to renal Pi wasting and impairs vitamin D activation. X-linked hypophosphatemic rickets (XLH) is the most common form of hereditary FGF23-related hypophosphatemia, and enhanced FGF receptor (FGFR) signaling in osteocytes may be involved in the pathogenesis of this disease. Increased extracellular Pi triggers signal transduction via FGFR to regulate gene expression, implying a close relationship between Pi metabolism and FGFR. An anti-FGF23 antibody, burosumab, has recently been developed as a new treatment for XLH. In addition to various forms of rickets/osteomalacia, hypophosphatasia (HPP) is characterized by impaired skeletal mineralization. HPP is caused by inactivating mutations in tissue-nonspecific alkaline phosphatase, an enzyme rich in MVs. The recent development of enzyme replacement therapy using bone-targeting recombinant alkaline phosphatase has improved the prognosis, motor function, and quality of life in patients with HPP. This links impaired skeletal mineralization with various conditions, and unraveling its pathogenesis will lead to more precise diagnoses and effective treatments.
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Affiliation(s)
- Toshimi Michigami
- Department of Bone and Mineral Research, Research Institute, Osaka Women’s and Children’s Hospital, Osaka Prefectural Hospital Organization, Izumi, Japan,Address for correspondence: Toshimi Michigami, MD, PhD Department of Bone and Mineral Research, Research I nstitute, Osaka Women’s and Children’s Hospital, Osaka Prefectural Hospital Organization, 840 Murodo-cho, Izumi, Osaka 594-1101, Japan Tel: +81-725-56-1220 Fax: +81-725-57-3021 E-mail:
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214
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Abstract
Chronic kidney disease (CKD) is a global health epidemic that accelerates cardiovascular disease, increases risk of infection, and causes anemia and bone disease, among other complications that collectively increase risk of premature death. Alterations in calcium and phosphate homeostasis have long been considered nontraditional risk factors for many of the most morbid outcomes of CKD. The discovery of fibroblast growth factor 23 (FGF23), which revolutionized the diagnosis and treatment of rare hereditary disorders of FGF23 excess that cause hypophosphatemic rickets, has also driven major paradigm shifts in our understanding of the pathophysiology and downstream end-organ complications of disordered mineral metabolism in CKD. As research of FGF23 in CKD has rapidly advanced, major new questions about its regulation and effects continuously emerge. These are promoting exciting innovations in laboratory, patient-oriented, and epidemiological research and stimulating clinical trials of new therapies and repurposing of existing ones to target FGF23.
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Affiliation(s)
- John Musgrove
- Division of Nephrology, Department of Medicine, Duke University School of Medicine, Durham, North Carolina 27710, USA;
| | - Myles Wolf
- Division of Nephrology, Department of Medicine, Duke University School of Medicine, Durham, North Carolina 27710, USA; .,Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina 27710, USA
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215
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Liu C, Zhao Z, Wang O, Li M, Xing X, Hsieh E, Fukumoto S, Jiang Y, Xia W. Earlier Onset in Autosomal Dominant Hypophosphatemic Rickets of R179 than R176 Mutations in Fibroblast Growth Factor 23: Report of 20 Chinese Cases and Review of the Literature. Calcif Tissue Int 2019; 105:476-486. [PMID: 31486862 DOI: 10.1007/s00223-019-00597-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 08/10/2019] [Indexed: 01/20/2023]
Abstract
Autosomal dominant hypophosphatemic rickets (ADHR) is a rare hereditary disorder characterized by variant onset ages and diverse phenotypes. Our aim is to explore the genotype-phenotype correlations between ADHR patients with R176 and R179 mutations in FGF23 gene. Clinical manifestations, laboratory examinations, and genetic analyses were collected from 20 patients in six Chinese ADHR kindreds in our hospital. Previously published ADHR literatures were reviewed. Among 20 Chinese ADHR mutation carriers, 11 patients revealed overt symptoms. 10/11 (90.9%) of which were females. Patients with R179 mutations presented with earlier onset than those with R176 mutation [1.3 (1.0, 37.0) years vs. 28.5 (19.0, 44.0) years]. More patients with R179 mutations had a history of rickets with lower extremity deformity [3/4 (75%) vs. 1/7 (14.3%), p < 0.05]. The serum phosphate, i-FGF23 and c-FGF23 levels of patients with R179 and R176 mutations were 0.47 ± 0.14 mmol/L versus 0.57 ± 0.17 mmol/L, 79.6 ± 87.0 pg/mL versus 79.9 ± 107.4 pg/mL, and 33.4 ± 3.0 RU/mL versus 121.3 ± 177.6 RU/mL, respectively. 7/11 of patients had iron deficiency at onset of disease. When combined with previously reported seven ADHR families, difference was observed in the age of onset among symptomatic patients with R179 and R176 mutations [1.0 (0.9, 37.0) years vs. 24.5 (1.2, 57.0) years, p < 0.05]. Patients with R179 mutation were more likely to have rickets than R176 mutation (11/13, 84.6% vs. 5/20, 25.0%, p < 0.01) and lower extremity deformity (10/13, 76.9% vs. 6/19, 31.6%, p < 0.01). ADHR patients with R179 mutations had earlier onset age and more rickets compared to those with mutations in R176, which partially explained the clinical heterogeneity of ADHR.
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Affiliation(s)
- Chang Liu
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Zhen Zhao
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Ou Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Mei Li
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Xiaoping Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China
| | - Evelyn Hsieh
- Section of Rheumatology, Department of Internal Medicine, Yale School of Medicine, New Haven, USA
| | - Seiji Fukumoto
- Fujii Memorial Institute of Medical Sciences, Tokushima, Japan
| | - Yan Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China.
| | - Weibo Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, The Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, China.
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216
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Coppolino G, Nicotera R, Cernaro V, Calimeri S, Leonardi G, Cosentino S, Comi A, Donato C, Lucia CM, Provenzano M, Michael A, Andreucci M. Iron Infusion and Induced Hypophosphatemia: The Role of Fibroblast Growth Factor-23. Ther Apher Dial 2019; 24:258-264. [PMID: 31483921 DOI: 10.1111/1744-9987.13435] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 07/26/2019] [Accepted: 08/30/2019] [Indexed: 12/11/2022]
Abstract
The mechanism of action of fibroblast growth factor-23 (FGF23) is becoming increasingly clearer as a result of studies that have defined its structure and pleiotropic effects. Furthermore, data are emerging on the effects exerted on this hormone by iron administration. Ten main iron formulations are recognized (with clear differences in composition and possible reactions of intolerance and anaphylaxis), which are indicated for iron deficiency anemia, including nephropathic subjects, as suggested by medical guidelines. With some types of iron formulation (especially iron carboxymaltose) a particular side effect has been observed: hypophosphatemia, mediated by FGF23. This review aims to draw attention to this correlation and the contradiction represented by the presence of both positive and negative modulation by FGF23, with the effects induced by its increase even after long-term treatment with iron formulation. However, more evidence is needed to understand the reasons for this differential stimulation.
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Affiliation(s)
- Giuseppe Coppolino
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Ramona Nicotera
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Valeria Cernaro
- Renal Unit, Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - Sebastiano Calimeri
- Renal Unit, Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy
| | - Giuseppe Leonardi
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Sonia Cosentino
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Alessandro Comi
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Cinzia Donato
- Nephrology and Dialysis Unit, Pugliese-Ciaccio" General Hospital, Catanzaro, Italy
| | - Citraro Maria Lucia
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Michele Provenzano
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Ashour Michael
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
| | - Michele Andreucci
- Renal Unit, Department of Health Sciences, "Magna Graecia" University, Catanzaro, Italy
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217
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Abstract
PURPOSE OF REVIEW To review the differential diagnosis of low bone mineral density (BMD). RECENT FINDINGS Osteoporosis is the most common cause of low BMD in adults; however, non-osteoporotic causes of low BMD should be considered in the differential diagnosis of patients with low BMD. Mild osteogenesis imperfecta, osteomalacia, and mineral and bone disorder of chronic kidney disease as well as several other rare diseases can be characterized by low BMD. This review summarizes the differential diagnosis of low BMD. It is important to differentiate osteoporosis from other causes of low BMD since treatment regimens can vary tremendously between these different disease processes. In fact, some treatments for osteoporosis could worsen or exacerbate the mineral abnormalities in other causes of low BMD.
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Affiliation(s)
- Smita Jha
- Clinical and Investigative Orthopedics Surgery Unit, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA.
- Section on Congenital Disorders, National Institutes of Health Clinical Center, 10 Center Drive, Bldg. 10-CRC, Room 1-5362, MSC-1504, Bethesda, MD, 20892, USA.
| | - Marquis Chapman
- National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Kelly Roszko
- National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892, USA
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218
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Jørgensen CS, Poulsen VML, Sandahl M, Underbjerg L, Kristensen SB, Piec I, Beck-Nielsen SS, Rejnmark L, Birkebæk NH. Milk Products in the Treatment of Hypophosphatemic Rickets: A Pilot Study. Int J Endocrinol Metab 2019; 17:e91454. [PMID: 31903094 PMCID: PMC6935710 DOI: 10.5812/ijem.91454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 07/24/2019] [Accepted: 09/02/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Standard treatment of hypophosphatemic rickets (HR) is oral phosphate tablets plus vitamin D. Due to the rapid absorption of phosphate tablets, frequent daily doses are necessary, which is cumbersome and may cause fluctuations in plasma phosphate and risk of secondary hyperparathyroidism. It was hypothesized that phosphate from milk or cheese is less rapidly absorbed, and reduces fluctuations in plasma phosphate. OBJECTIVES The current randomized, multiple crossover study aimed at investigating if an equivalent phosphate dose given as milk or cheese is comparable to phosphate tablets in patients with HR. METHODS Seven females with HR were included. They went through three different four-day treatment sessions of either oral phosphate tablets consisting of 800 mg elemental phosphorus divided into five doses over the day or an equivalent phosphorus dose ingested as skimmed milk or cheese divided over five daily doses. Blood and urine samples were taken from patients after each treatment session. Except the usual doses of vitamin D, no phosphate or calcium-modifying treatments were allowed. Statistical analyses were performed using mixed models. RESULTS Treatment feasibility was independent of the phosphorus source. The study demonstrated reduced plasma levels of parathyroid hormone (PTH), reduced fluctuations in plasma phosphate and plasma PTH, and reduced renal phosphate excretion when ingesting phosphorus supplementation as milk compared to phosphate tablets. The same trend was observed when administering phosphorus as cheese, though not statistically significant. CONCLUSIONS Phosphorus supplements can be administered as phosphate tablets, milk or cheese when given in equimolar doses. The current study findings indicated that milk may be superior to phosphate tablets as the phosphate source in patients with HR.
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Affiliation(s)
- Cecilie Siggaard Jørgensen
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus, Denmark
- Corresponding Author: Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus, Denmark. +45-61161606,
| | - Vibe Morgana Lund Poulsen
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus, Denmark
- Corresponding Author: Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus, Denmark. +45-61101151,
| | - Mads Sandahl
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Line Underbjerg
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Simon Bang Kristensen
- Department of Public Health, Section for Biostatistics, Aarhus University, Aarhus, Denmark
| | - Isabelle Piec
- University of East Anglia, Norwich Research Park, Norwich, England
| | | | - Lars Rejnmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Niels Holtum Birkebæk
- Department of Paediatrics and Adolescent Medicine, Aarhus University Hospital, Aarhus, Denmark
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219
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Huang J, Bao X, Xia W, Zhu L, Zhang J, Ma J, Jiang N, Yang J, Chen Q, Jing T, Liu J, Ma D, Xu G. Functional analysis of a de novo mutation c.1692 del A of the PHEX gene in a Chinese family with X-linked hypophosphataemic rickets. Bone Joint Res 2019; 8:405-413. [PMID: 31537998 PMCID: PMC6719531 DOI: 10.1302/2046-3758.88.bjr-2018-0276.r1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Objectives X-linked hypophosphataemic rickets (XLHR) is a disease of impaired bone mineralization characterized by hypophosphataemia caused by renal phosphate wasting. The main clinical manifestations of the disorder are O-shaped legs, X-shaped legs, delayed growth, and bone pain. XLHR is the most common inheritable form of rickets, with an incidence of 1/20 000 in humans. It accounts for approximately 80% of familial cases of hypophosphataemia and serves as the prototype of defective tubular phosphate (PO43+) transport, due to extra renal defects resulting in unregulated FGF23 activity. XLHR is caused by loss-of-function mutations in the PHEX gene. The aim of this research was to identify the genetic defect responsible for familial hypophosphataemic rickets in a four-generation Chinese Han pedigree and to analyze the function of this mutation. Methods The genome DNA samples of all members in the pedigree were extracted from whole blood. We sequenced all exons of the PHEX and FGF23 genes, as well as the adjacent splice site sequence with Sanger sequencing. Next, we analyzed the de novo mutation c.1692 del A of the PHEX gene with an online digital service and investigated the mutant PHEX with SWISS-MODEL, immunofluorescence, and protein stability detection. Results Through Sanger sequencing, we found a de novo mutation, c.1692 del A, in exon 16 of the PHEX gene in this pedigree. This mutation can make the PHEX protein become unstable and decay rapidly, which results in familial XLHR. Conclusion We have found a de novo loss-of-function mutation, c.1692 del A, in exon 16 of the PHEX gene that can cause XLHR. Cite this article: J. Huang, X. Bao, W. Xia, L. Zhu, J. Zhang, J. Ma, N. Jiang, J. Yang, Q. Chen, T. Jing, J. Liu, D. Ma, G. Xu. Functional analysis of a de novo mutation c.1692 del A of the PHEX gene in a Chinese family with X-linked hypophosphataemic rickets. Bone Joint Res 2019;8:405–413. DOI: 10.1302/2046-3758.88.BJR-2018-0276.R1.
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Affiliation(s)
- Jianbo Huang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Xiaogang Bao
- Department of Orthopedic Surgery, The Spine Surgical Center, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Wenjun Xia
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Lingjun Zhu
- Department of Orthopedic Surgery, The Spine Surgical Center, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Jin Zhang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Jing Ma
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Nan Jiang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Jichun Yang
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Qing Chen
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Tianrui Jing
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Jia Liu
- Department of Orthopedic Surgery, The Spine Surgical Center, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Duan Ma
- Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; Research Center for Birth Defects, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Guohua Xu
- Department of Orthopedic Surgery, The Spine Surgical Center, Changzheng Hospital, Second Military Medical University, Shanghai, China
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220
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FGF23 at the crossroads of phosphate, iron economy and erythropoiesis. Nat Rev Nephrol 2019; 16:7-19. [PMID: 31519999 DOI: 10.1038/s41581-019-0189-5] [Citation(s) in RCA: 149] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2019] [Indexed: 12/20/2022]
Abstract
Fibroblast growth factor 23 (FGF23) was initially characterized as an important regulator of phosphate and calcium homeostasis. New research advances demonstrate that FGF23 is also linked to iron economy, inflammation and erythropoiesis. These advances have been fuelled, in part, by the serendipitous development of two distinct FGF23 assays that can substitute for invasive bone biopsies to infer the activity of the three main steps of FGF23 regulation in bone: transcription, post-translational modification and peptide cleavage. This 'liquid bone biopsy for FGF23 dynamics' enables large-scale longitudinal studies of FGF23 regulation that would otherwise be impossible in humans. The balance between FGF23 production, post-translational modification and cleavage is maintained or perturbed in different hereditary monogenic conditions and in acquired conditions that mimic these genetic disorders, including iron deficiency, inflammation, treatment with ferric carboxymaltose and chronic kidney disease. Looking ahead, a deeper understanding of the relationships between FGF23 regulation, iron homeostasis and erythropoiesis can be leveraged to devise novel therapeutic targets for treatment of anaemia and states of FGF23 excess, including chronic kidney disease.
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221
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Abstract
Members of the fibroblast growth factor (FGF) family play pleiotropic roles in cellular and metabolic homeostasis. During evolution, the ancestor FGF expands into multiple members by acquiring divergent structural elements that enable functional divergence and specification. Heparan sulfate-binding FGFs, which play critical roles in embryonic development and adult tissue remodeling homeostasis, adapt to an autocrine/paracrine mode of action to promote cell proliferation and population growth. By contrast, FGF19, 21, and 23 coevolve through losing binding affinity for extracellular matrix heparan sulfate while acquiring affinity for transmembrane α-Klotho (KL) or β-KL as a coreceptor, thereby adapting to an endocrine mode of action to drive interorgan crosstalk that regulates a broad spectrum of metabolic homeostasis. FGF19 metabolic axis from the ileum to liver negatively controls diurnal bile acid biosynthesis. FGF21 metabolic axes play multifaceted roles in controlling the homeostasis of lipid, glucose, and energy metabolism. FGF23 axes from the bone to kidney and parathyroid regulate metabolic homeostasis of phosphate, calcium, vitamin D, and parathyroid hormone that are important for bone health and systemic mineral balance. The significant divergence in structural elements and multiple functional specifications of FGF19, 21, and 23 in cellular and organismal metabolism instead of cell proliferation and growth sufficiently necessitate a new unified and specific term for these three endocrine FGFs. Thus, the term "FGF Metabolic Axis," which distinguishes the unique pathways and functions of endocrine FGFs from other autocrine/paracrine mitogenic FGFs, is coined.
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Affiliation(s)
- Xiaokun Li
- School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, 325035, China.
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222
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He Q, Shumate LT, Matthias J, Aydin C, Wein MN, Spatz JM, Goetz R, Mohammadi M, Plagge A, Divieti Pajevic P, Bastepe M. A G protein-coupled, IP3/protein kinase C pathway controlling the synthesis of phosphaturic hormone FGF23. JCI Insight 2019; 4:125007. [PMID: 31484825 PMCID: PMC6777913 DOI: 10.1172/jci.insight.125007] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 08/01/2019] [Indexed: 12/23/2022] Open
Abstract
Dysregulated actions of bone-derived phosphaturic hormone fibroblast growth factor 23 (FGF23) result in several inherited diseases, such as X-linked hypophosphatemia (XLH), and contribute substantially to the mortality in kidney failure. Mechanisms governing FGF23 production are poorly defined. We herein found that ablation of the Gq/11α-like, extralarge Gα subunit (XLαs), a product of GNAS, exhibits FGF23 deficiency and hyperphosphatemia in early postnatal mice (XLKO). FGF23 elevation in response to parathyroid hormone, a stimulator of FGF23 production via cAMP, was intact in XLKO mice, while skeletal levels of protein kinase C isoforms α and δ (PKCα and PKCδ) were diminished. XLαs ablation in osteocyte-like Ocy454 cells suppressed the levels of FGF23 mRNA, inositol 1,4,5-trisphosphate (IP3), and PKCα/PKCδ proteins. PKC activation in vivo via injecting phorbol myristate acetate (PMA) or by constitutively active Gqα-Q209L in osteocytes and osteoblasts promoted FGF23 production. Molecular studies showed that the PKC activation-induced FGF23 elevation was dependent on MAPK signaling. The baseline PKC activity was elevated in bones of Hyp mice, a model of XLH. XLαs ablation significantly, but modestly, reduced serum FGF23 and elevated serum phosphate in Hyp mice. These findings reveal a potentially hitherto-unknown mechanism of FGF23 synthesis involving a G protein-coupled IP3/PKC pathway, which may be targeted to fine-tune FGF23 levels.
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Affiliation(s)
- Qing He
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Lauren T. Shumate
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Julia Matthias
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Cumhur Aydin
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Department of Endodontics, Gulhane Faculty of Dentistry, University of Health Sciences, Ankara, Turkey
| | - Marc N. Wein
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Jordan M. Spatz
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Regina Goetz
- Department of Biochemistry & Molecular Pharmacology, New York University School of Medicine, New York, New York, USA
| | - Moosa Mohammadi
- Department of Biochemistry & Molecular Pharmacology, New York University School of Medicine, New York, New York, USA
| | - Antonius Plagge
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Paola Divieti Pajevic
- Department of Molecular & Cell Biology, Boston University Goldman School of Dental Medicine, Boston, Massachusetts, USA
| | - Murat Bastepe
- Endocrine Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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223
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Abstract
Fibroblast growth factor 23 (FGF23), one of the endocrine fibroblast growth factors, is a principal regulator in the maintenance of serum phosphorus concentration. Binding to its cofactor αKlotho and a fibroblast growth factor receptor is essential for its activity. Its regulation and interaction with other factors in the bone-parathyroid-kidney axis is complex. FGF23 reduces serum phosphorus concentration through decreased reabsorption of phosphorus in the kidney and by decreasing 1,25 dihydroxyvitamin D (1,25(OH)2D) concentrations. Various FGF23-mediated disorders of renal phosphate wasting share similar clinical and biochemical features. The most common of these is X-linked hypophosphatemia (XLH). Additional disorders of FGF23 excess include autosomal dominant hypophosphatemic rickets, autosomal recessive hypophosphatemic rickets, fibrous dysplasia, and tumor-induced osteomalacia. Treatment is challenging, requiring careful monitoring and titration of dosages to optimize effectiveness and to balance side effects. Conventional therapy for XLH and other disorders of FGF23-mediated hypophosphatemia involves multiple daily doses of oral phosphate salts and active vitamin D analogs, such as calcitriol or alfacalcidol. Additional treatments may be used to help address side effects of conventional therapy such as thiazides to address hypercalciuria or nephrocalcinosis, and calcimimetics to manage hyperparathyroidism. The recent development and approval of an anti-FGF23 antibody, burosumab, for use in XLH provides a novel treatment option.
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Affiliation(s)
- Anisha Gohil
- Indiana University School of Medicine, Riley Hospital for Children, Fellow, Endocrinology and Diabetes, 705 Riley Hospital Drive, Room 5960, Indianapolis, IN 46202, USA, E-mail:
| | - Erik A Imel
- Indiana University School of Medicine, Riley Hospital for Children, Associate Professor of Medicine and Pediatrics, 1120 West Michigan Street, CL 459, Indianapolis, IN 46202, USA
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224
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Czaya B, Faul C. The Role of Fibroblast Growth Factor 23 in Inflammation and Anemia. Int J Mol Sci 2019; 20:E4195. [PMID: 31461904 PMCID: PMC6747522 DOI: 10.3390/ijms20174195] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 02/07/2023] Open
Abstract
In patients with chronic kidney disease (CKD), adverse outcomes such as systemic inflammation and anemia are contributing pathologies which increase the risks for cardiovascular mortality. Amongst these complications, abnormalities in mineral metabolism and the metabolic milieu are associated with chronic inflammation and iron dysregulation, and fibroblast growth factor 23 (FGF23) is a risk factor in this context. FGF23 is a bone-derived hormone that is essential for regulating vitamin D and phosphate homeostasis. In the early stages of CKD, serum FGF23 levels rise 1000-fold above normal values in an attempt to maintain normal phosphate levels. Despite this compensatory action, clinical CKD studies have demonstrated powerful and dose-dependent associations between FGF23 levels and higher risks for mortality. A prospective pathomechanism coupling elevated serum FGF23 levels with CKD-associated anemia and cardiovascular injury is its strong association with chronic inflammation. In this review, we will examine the current experimental and clinical evidence regarding the role of FGF23 in renal physiology as well as in the pathophysiology of CKD with an emphasis on chronic inflammation and anemia.
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Affiliation(s)
- Brian Czaya
- Division of Nephrology, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Christian Faul
- Division of Nephrology, Department of Medicine, The University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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225
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Rupp T, Butscheidt S, Vettorazzi E, Oheim R, Barvencik F, Amling M, Rolvien T. High FGF23 levels are associated with impaired trabecular bone microarchitecture in patients with osteoporosis. Osteoporos Int 2019; 30:1655-1662. [PMID: 31044263 DOI: 10.1007/s00198-019-04996-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 04/21/2019] [Indexed: 11/29/2022]
Abstract
UNLABELLED This cross-sectional study examined the associations between c-terminal FGF23 levels, laboratory markers of bone metabolism and bone microarchitecture in 82 patients with osteoporosis. Higher FGF23 levels were associated with impaired trabecular but not cortical bone microarchitecture, and this was confirmed after adjusting for confounding variables such as age or BMI. INTRODUCTION Fibroblast growth factor 23 (FGF23) is an endocrine hormone-regulating phosphate and vitamin D metabolism. While its mode of action is well understood in diseases such as hereditary forms of rickets or tumor-induced osteomalacia, the interpretation of FGF23 levels in patients with osteoporosis with regard to bone microarchitecture is less clear. METHODS C-terminal FGF23 levels and bone turnover markers were assessed in 82 patients with osteoporosis (i.e., DXA T-score ≤ - 2.5 at the lumbar spine or total hip). Bone microarchitecture was measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) at the distal radius and tibia. Data were analyzed in a cross-sectional design using correlation and regression models. RESULTS We found a significant negative logarithmic correlation between FGF23 levels and trabecular but not cortical bone microarchitecture at both skeletal sites. Furthermore, using a multiple linear regression model, we confirmed FGF23 as a predictor for reduced trabecular parameters even when adjusting for confounding factors such as age, BMI, phosphate, bone-specific alkaline phosphatase, vitamin D3, and PTH. CONCLUSIONS Taken together, high FGF23 levels are associated with impaired trabecular bone microarchitecture in osteoporosis patients, and this association seems to occur after adjustment of confounding variables including phosphate and vitamin D. Future longitudinal studies are now needed to validate our findings and investigate FGF23 in relation to fracture risk.
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Affiliation(s)
- T Rupp
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - S Butscheidt
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
- Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - E Vettorazzi
- Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - R Oheim
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - F Barvencik
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - M Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany
| | - T Rolvien
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestr. 59, 22529, Hamburg, Germany.
- Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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226
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Kawaguchi Y, Kitajima I, Nakano M, Yasuda T, Seki S, Suzuki K, Yahara Y, Makino H, Ujihara Y, Ueno T, Kimura T. Increase of the Serum FGF-23 in Ossification of the Posterior Longitudinal Ligament. Global Spine J 2019; 9:492-498. [PMID: 31431871 PMCID: PMC6686384 DOI: 10.1177/2192568218801015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
STUDY DESIGN Case-control study. OBJECTIVES To determine the possible pathogenesis of ossification of the posterior longitudinal ligament (OPLL) in regard to the serum concentration of fibroblast growth factor 23 (FGF-23). METHODS The study included 95 patients with OPLL and a control group of 73 age- and sex-matched volunteers. The serum concentrations of FGF-23, creatinine (Cre), alkaline phosphatase, calcium (Ca), inorganic phosphate (Pi), and hypersensitive C-reactive protein (hs-CRP) were analyzed from blood samples, and Cre, Ca, Pi, and tubular reabsorption of phosphate were measured using urine samples. We evaluated the severity of ossified spinal lesions in patients with OPLL according to the ossification index (the OP index and the OS index). Data was compared between the OPLL and control group and between the OPLL progression and no progression group. RESULTS Serum FGF-23 and hs-CRP were higher, and serum Pi was lower in patients with OPLL than in the controls. There was a positive correlation between FGF-23 and hs-CRP and a negative correlation between serum Pi and the OS index; however, the correlations were very weak. Overall, 31.7% of patients had progression of OPLL during follow-up. FGF-23 and hs-CRP were higher in the progression group than in the no progression group. CONCLUSIONS These results might indicate that FGF-23 and hs-CRP are positive markers for OPLL. Phosphate metabolism via FGF-23 might be a target for future study on the pathogenesis of OPLL.
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Affiliation(s)
- Yoshiharu Kawaguchi
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan,Yoshiharu Kawaguchi, Department of Orthopaedic Surgery, University of Toyama, Faculty of Medicine, 2630, Sugitani, Toyama 930-0194, Japan.
| | - Isao Kitajima
- Clinical Laboratory Center, Toyama University Hospital, Toyama, Japan
| | - Masato Nakano
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
| | - Taketoshi Yasuda
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
| | - Shoji Seki
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
| | - Kayo Suzuki
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
| | - Yasuhito Yahara
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
| | - Hiroto Makino
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
| | - Yasuhiro Ujihara
- Clinical Laboratory Center, Toyama University Hospital, Toyama, Japan
| | - Tomohiro Ueno
- Clinical Laboratory Center, Toyama University Hospital, Toyama, Japan
| | - Tomoatsu Kimura
- Department of Orthopaedic Surgery, University of Toyama, Toyama, Japan
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227
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Layman AAK, Joshi S, Shah S. Metastatic prostate cancer presenting as tumour-induced osteomalacia. BMJ Case Rep 2019; 12:e229434. [PMID: 31315844 PMCID: PMC6663299 DOI: 10.1136/bcr-2019-229434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2019] [Indexed: 11/04/2022] Open
Abstract
Tumour-induced osteomalacia (TIO), or oncogenic osteomalacia, is a paraneoplastic syndrome marked by hypophosphataemia, renal phosphate wasting, bone pain, weakness, and fractures. The syndrome has been reported with both benign and malignant tumours including parotid gland basal cell tumours, thyroid carcinomas, colon adenocarcinomas, and prostate cancer. Often, the syndrome is marked by an insidious course during which patients present with generalised bony pain and weakness, which do not resolve until the underlying tumour is identified and treated. We present a case of a patient with Parkinson's disease whose subacute weakness, lower extremity paresis, and renal phosphate wasting led to the synchronous diagnosis of metastatic prostate adenocarcinoma and TIO.
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Affiliation(s)
- Awo Akosua K Layman
- Perelman School of Medicine, Medical Scientist Training Program, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Shivam Joshi
- Internal Medicine, New York University, New York, New York, USA
| | - Sanjeev Shah
- Renal, Electrolyte, and Hypertension Division, University of Pennsylvania, Philadelphia, Pennsylvania, USA
- Medicine, Corporal Michael J Crescenz VA Medical Center, Philadelphia, Pennsylvania, USA
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228
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Pereira RC, Salusky IB, Roschger P, Klaushofer K, Yadin O, Freymiller EG, Bowen R, Delany AM, Fratzl-Zelman N, Wesseling-Perry K. Impaired osteocyte maturation in the pathogenesis of renal osteodystrophy. Kidney Int 2019; 94:1002-1012. [PMID: 30348285 DOI: 10.1016/j.kint.2018.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 07/18/2018] [Accepted: 08/09/2018] [Indexed: 12/18/2022]
Abstract
Pediatric renal osteodystrophy is characterized by skeletal mineralization defects, but the role of osteoblast and osteocyte maturation in the pathogenesis of these defects is unknown. We evaluated markers of osteocyte maturation and programmed cell death in iliac crest biopsy samples from pediatric dialysis patients and healthy controls. We evaluated the relationship between numbers of fibroblast growth factor 23 (FGF23)-expressing osteocytes and histomorphometric parameters of skeletal mineralization. We confirmed that chronic kidney disease (CKD) causes intrinsic changes in bone cell maturation using an in vitro model of primary osteoblasts from patients with CKD and healthy controls. FGF23 co-localized with the early osteocyte marker E11/gp38, suggesting that FGF23 is a marker of early osteocyte maturation. Increased numbers of early osteocytes and decreased osteocyte apoptosis characterized CKD bone. Numbers of FGF23-expressing osteocytes were highest in patients with preserved skeletal mineralization indices, and packets of matrix surrounding FGF23-expressing osteocytes appeared to have entered secondary mineralization. Primary osteoblasts from patients with CKD retained impaired maturation and mineralization characteristics in vitro. Addition of FGF23 did not affect primary osteoblast mineralization. Thus, CKD is associated with intrinsic changes in osteoblast and osteocyte maturation, and FGF23 appears to mark a relatively early stage in osteocyte maturation. Improved control of renal osteodystrophy and FGF23 excess will require further investigation into the pathogenesis of CKD-mediated osteoblast and osteocyte maturation failure.
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Affiliation(s)
- Renata C Pereira
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Isidro B Salusky
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Paul Roschger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGK and AUVA Trauma Centre Meidling, 1(st) Medical Department, Hanusch Hospital, Vienna, Austria
| | - Klaus Klaushofer
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGK and AUVA Trauma Centre Meidling, 1(st) Medical Department, Hanusch Hospital, Vienna, Austria
| | - Ora Yadin
- Department of Pediatrics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | | | - Richard Bowen
- Department of Orthopedics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | - Anne M Delany
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut, USA
| | - Nadja Fratzl-Zelman
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGK and AUVA Trauma Centre Meidling, 1(st) Medical Department, Hanusch Hospital, Vienna, Austria
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229
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Bär L, Stournaras C, Lang F, Föller M. Regulation of fibroblast growth factor 23 (FGF23) in health and disease. FEBS Lett 2019; 593:1879-1900. [PMID: 31199502 DOI: 10.1002/1873-3468.13494] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 03/26/2019] [Accepted: 03/27/2019] [Indexed: 12/19/2022]
Abstract
Fibroblast growth factor 23 (FGF23) is mainly produced in the bone and, upon secretion, forms a complex with a FGF receptor and coreceptor αKlotho. FGF23 can exert several endocrine functions, such as inhibiting renal phosphate reabsorption and 1,25-dihydroxyvitamin D3 production. Moreover, it has paracrine activities on several cell types, including neutrophils and hepatocytes. Klotho and Fgf23 deficiencies result in pathologies otherwise encountered in age-associated diseases, mainly as a result of hyperphosphataemia-dependent calcification. FGF23 levels are also perturbed in the plasma of patients with several disorders, including kidney or cardiovascular diseases. Here, we review mechanisms controlling FGF23 production and discuss how FGF23 regulation is perturbed in disease.
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Affiliation(s)
- Ludmilla Bär
- Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Christos Stournaras
- Institute of Biochemistry, University of Crete Medical School, Heraklion, Greece
| | - Florian Lang
- Institute of Physiology, University of Tübingen, Germany
| | - Michael Föller
- Institute of Physiology, University of Hohenheim, Stuttgart, Germany
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230
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Abstract
Acute kidney injury (AKI) is associated with many of the same mineral metabolite abnormalities that are observed in chronic kidney disease. These include increased circulating levels of the osteocyte-derived, vitamin D-regulating hormone, fibroblast growth factor 23 (FGF23), and decreased renal expression of klotho, the co-receptor for FGF23. Recent data have indicated that increased FGF23 and decreased klotho levels in the blood and urine could serve as novel predictive biomarkers of incident AKI, or as novel prognostic biomarkers of adverse outcomes in patients with established AKI. In addition, because FGF23 and klotho exert numerous classic as well as off-target effects on a variety of organ systems, targeting their dysregulation in AKI may represent a unique opportunity for therapeutic intervention. We review the pathophysiology, kinetics, and regulation of FGF23 and klotho in animal and human studies of AKI, and we discuss the challenges and opportunities involved in targeting FGF23 and klotho therapeutically.
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Affiliation(s)
- Marta Christov
- Department of Medicine, New York Medical College, Valhalla, NY.
| | - Javier A Neyra
- Division of Nephrology, Bone and Mineral Metabolism, Department of Internal Medicine, University of Kentucky, Lexington, KY; Division of Nephrology, Department of Internal Medicine, University of Texas Southwestern, Dallas, TX
| | - Sanjeev Gupta
- Department of Medicine, New York Medical College, Valhalla, NY
| | - David E Leaf
- Division of Renal Medicine, Brigham and Women's Hospital, Boston, MA
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231
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232
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Cox TC, Lidral AC, McCoy JC, Liu H, Cox LL, Zhu Y, Anderson RD, Moreno Uribe LM, Anand D, Deng M, Richter CT, Nidey NL, Standley JM, Blue EE, Chong JX, Smith JD, Kirk EP, Venselaar H, Krahn KN, van Bokhoven H, Zhou H, Cornell RA, Glass IA, Bamshad MJ, Nickerson DA, Murray JC, Lachke SA, Thompson TB, Buckley MF, Roscioli T. Mutations in GDF11 and the extracellular antagonist, Follistatin, as a likely cause of Mendelian forms of orofacial clefting in humans. Hum Mutat 2019; 40:1813-1825. [PMID: 31215115 DOI: 10.1002/humu.23793] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 05/02/2019] [Accepted: 05/09/2019] [Indexed: 12/30/2022]
Abstract
Cleft lip with or without cleft palate (CL/P) is generally viewed as a complex trait with multiple genetic and environmental contributions. In 70% of cases, CL/P presents as an isolated feature and/or deemed nonsyndromic. In the remaining 30%, CL/P is associated with multisystem phenotypes or clinically recognizable syndromes, many with a monogenic basis. Here we report the identification, via exome sequencing, of likely pathogenic variants in two genes that encode interacting proteins previously only linked to orofacial clefting in mouse models. A variant in GDF11 (encoding growth differentiation factor 11), predicting a p.(Arg298Gln) substitution at the Furin protease cleavage site, was identified in one family that segregated with CL/P and both rib and vertebral hypersegmentation, mirroring that seen in Gdf11 knockout mice. In the second family in which CL/P was the only phenotype, a mutation in FST (encoding the GDF11 antagonist, Follistatin) was identified that is predicted to result in a p.(Cys56Tyr) substitution in the region that binds GDF11. Functional assays demonstrated a significant impact of the specific mutated amino acids on FST and GDF11 function and, together with embryonic expression data, provide strong evidence for the importance of GDF11 and Follistatin in the regulation of human orofacial development.
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Affiliation(s)
- Timothy C Cox
- Division of Craniofacial Medicine, Department of Pediatrics, University of Washington, Seattle, Washington.,Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, Washington.,Department of Oral & Craniofacial Science, School of Dentistry, University of Missouri-Kansas City, Kansas City, Missouri
| | | | - Jason C McCoy
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, Ohio
| | - Huan Liu
- Department of Anatomy and Cell Biology and Anatomy, University of Iowa, Iowa City, Iowa
| | - Liza L Cox
- Division of Craniofacial Medicine, Department of Pediatrics, University of Washington, Seattle, Washington.,Center for Developmental Biology & Regenerative Medicine, Seattle Children's Research Institute, Seattle, Washington.,Department of Oral & Craniofacial Science, School of Dentistry, University of Missouri-Kansas City, Kansas City, Missouri.,Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Ying Zhu
- New South Wales Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia.,Genetics of Learning Disability Service, Hunter Genetics, Waratah, New South Wales, Australia
| | - Ryan D Anderson
- Department of Oral & Craniofacial Science, School of Dentistry, University of Missouri-Kansas City, Kansas City, Missouri
| | - Lina M Moreno Uribe
- Department of Orthodontics & the Iowa Institute for Oral Health Research, University of Iowa, Iowa City, Iowa
| | - Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, Delaware
| | - Mei Deng
- Birth Defects Research Laboratory, University of Washington, Seattle, Washington
| | - Chika T Richter
- Department of Orthodontics & the Iowa Institute for Oral Health Research, University of Iowa, Iowa City, Iowa
| | - Nichole L Nidey
- Department of Pediatrics, University of Iowa, Iowa City, Iowa
| | | | - Elizabeth E Blue
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, Washington
| | - Jessica X Chong
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, Washington
| | - Joshua D Smith
- Department of Genome Sciences, University of Washington, Seattle, Washington
| | - Edwin P Kirk
- New South Wales Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospital, New South Wales, Australia
| | - Hanka Venselaar
- Centre for Molecular and Biomolecular Informatics, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Katy N Krahn
- UVA Center for Advanced Medical Analytics, School of Medicine, University of Virginia, Charlottesville, Virginia
| | - Hans van Bokhoven
- Department of Human Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands.,Department of Cognitive Neurosciences, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Huiqing Zhou
- Department of Human Genetics, Radboud University Medical Centre, Nijmegen, The Netherlands.,Department of Molecular Developmental Biology, Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - Robert A Cornell
- Department of Anatomy and Cell Biology and Anatomy, University of Iowa, Iowa City, Iowa
| | - Ian A Glass
- Birth Defects Research Laboratory, University of Washington, Seattle, Washington.,Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, Washington
| | - Michael J Bamshad
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, Washington.,Department of Genome Sciences, University of Washington, Seattle, Washington
| | - Deborah A Nickerson
- Department of Genome Sciences, University of Washington, Seattle, Washington
| | | | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, Delaware
| | - Thomas B Thompson
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, Ohio
| | - Michael F Buckley
- New South Wales Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia
| | - Tony Roscioli
- New South Wales Health Pathology, Prince of Wales Hospital, Randwick, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospital, New South Wales, Australia.,Prince of Wales Clinical School, University of New South Wales, Randwick, New South Wales, Australia.,Neuroscience Research Australia (NeuRA), University of New South Wales, Sydney, New South Wales, Australia
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233
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Lerner UH, Kindstedt E, Lundberg P. The critical interplay between bone resorbing and bone forming cells. J Clin Periodontol 2019; 46 Suppl 21:33-51. [DOI: 10.1111/jcpe.13051] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Revised: 11/05/2018] [Accepted: 12/01/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Ulf H. Lerner
- Centre for Bone and Arthritis Research at Department of Internal Medicine and Clinical Nutrition; Institute of Medicine; Sahlgrenska Academy; University of Gothenburg; Gothenburg Sweden
- Department of Odontology; Division of Molecular Periodontology; Umeå University; Umeå Sweden
| | - Elin Kindstedt
- Department of Odontology; Division of Molecular Periodontology; Umeå University; Umeå Sweden
| | - Pernilla Lundberg
- Department of Odontology; Division of Molecular Periodontology; Umeå University; Umeå Sweden
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234
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Hannan FM, Newey PJ, Whyte MP, Thakker RV. Genetic approaches to metabolic bone diseases. Br J Clin Pharmacol 2019; 85:1147-1160. [PMID: 30357886 PMCID: PMC6533455 DOI: 10.1111/bcp.13803] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 10/12/2018] [Accepted: 10/15/2018] [Indexed: 12/13/2022] Open
Abstract
Metabolic bone diseases comprise a diverse group of disorders characterized by alterations in skeletal homeostasis, and are often associated with abnormal circulating concentrations of calcium, phosphate or vitamin D metabolites. These diseases commonly have a genetic basis and represent either a monogenic disorder due to a germline or somatic single gene mutation, or an oligogenic or polygenic disorder that involves variants in more than one gene. Germline single gene mutations causing Mendelian diseases typically have a high penetrance, whereas the genetic variations causing oligogenic or polygenic disorders are each associated with smaller effects with additional contributions from environmental factors. Recognition of familial monogenic disorders is of clinical importance to facilitate timely investigations and management of the patient and any affected relatives. The diagnosis of monogenic metabolic bone disease requires careful clinical evaluation of the large diversity of symptoms and signs associated with these disorders. Thus, the clinician must pursue a systematic approach beginning with a detailed history and physical examination, followed by appropriate laboratory and skeletal imaging evaluations. Finally, the clinician must understand the increasing number and complexity of molecular genetic tests available to ensure their appropriate use and interpretation.
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Affiliation(s)
- Fadil M. Hannan
- Academic Endocrine Unit, Radcliffe Department of Medicine,University of OxfordOxfordUK
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic DiseaseUniversity of LiverpoolLiverpoolUK
| | - Paul J. Newey
- Division of Molecular & Clinical Medicine, Ninewells Hospital & Medical SchoolUniversity of DundeeUK
| | - Michael P. Whyte
- Center for Metabolic Bone Disease and Molecular ResearchShriners Hospital for ChildrenSt. LouisMO63110USA
- Division of Bone and Mineral Diseases, Department of Internal MedicineWashington University School of Medicine at Barnes‐Jewish HospitalSt. LouisMO63110USA
| | - Rajesh V. Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine,University of OxfordOxfordUK
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235
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Brommage R, Powell DR, Vogel P. Predicting human disease mutations and identifying drug targets from mouse gene knockout phenotyping campaigns. Dis Model Mech 2019; 12:dmm038224. [PMID: 31064765 PMCID: PMC6550044 DOI: 10.1242/dmm.038224] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Two large-scale mouse gene knockout phenotyping campaigns have provided extensive data on the functions of thousands of mammalian genes. The ongoing International Mouse Phenotyping Consortium (IMPC), with the goal of examining all ∼20,000 mouse genes, has examined 5115 genes since 2011, and phenotypic data from several analyses are available on the IMPC website (www.mousephenotype.org). Mutant mice having at least one human genetic disease-associated phenotype are available for 185 IMPC genes. Lexicon Pharmaceuticals' Genome5000™ campaign performed similar analyses between 2000 and the end of 2008 focusing on the druggable genome, including enzymes, receptors, transporters, channels and secreted proteins. Mutants (4654 genes, with 3762 viable adult homozygous lines) with therapeutically interesting phenotypes were studied extensively. Importantly, phenotypes for 29 Lexicon mouse gene knockouts were published prior to observations of similar phenotypes resulting from homologous mutations in human genetic disorders. Knockout mouse phenotypes for an additional 30 genes mimicked previously published human genetic disorders. Several of these models have helped develop effective treatments for human diseases. For example, studying Tph1 knockout mice (lacking peripheral serotonin) aided the development of telotristat ethyl, an approved treatment for carcinoid syndrome. Sglt1 (also known as Slc5a1) and Sglt2 (also known as Slc5a2) knockout mice were employed to develop sotagliflozin, a dual SGLT1/SGLT2 inhibitor having success in clinical trials for diabetes. Clinical trials evaluating inhibitors of AAK1 (neuropathic pain) and SGLT1 (diabetes) are underway. The research community can take advantage of these unbiased analyses of gene function in mice, including the minimally studied 'ignorome' genes.
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Affiliation(s)
- Robert Brommage
- Department of Metabolism Research, Lexicon Pharmaceuticals, 8800 Technology Forest Place, The Woodlands, TX 77381, USA
| | - David R Powell
- Department of Metabolism Research, Lexicon Pharmaceuticals, 8800 Technology Forest Place, The Woodlands, TX 77381, USA
| | - Peter Vogel
- St. Jude Children's Research Hospital, Pathology, MS 250, Room C5036A, 262 Danny Thomas Place, Memphis, TN 38105, USA
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236
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Takashi Y, Ishizu M, Mori H, Miyashita K, Sakamoto F, Katakami N, Matsuoka TA, Yasuda T, Hashida S, Matsuhisa M, Kuroda A. Circulating osteocalcin as a bone-derived hormone is inversely correlated with body fat in patients with type 1 diabetes. PLoS One 2019; 14:e0216416. [PMID: 31050684 PMCID: PMC6499427 DOI: 10.1371/journal.pone.0216416] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 04/21/2019] [Indexed: 02/06/2023] Open
Abstract
The objective of the present study was to investigate the correlations between serum undercarboxylated osteocalcin (ucOC) or osteocalcin (OC) concentrations and %body fat, serum adiponectin and free-testosterone concentration, muscle strength and dose of exogenous insulin in patients with type 1 diabetes. We recruited 73 Japanese young adult patients with childhood-onset type 1 diabetes. All participants were receiving insulin replacement therapy. The correlations between logarithmic serum ucOC or OC concentrations and each parameter were examined. Serum ucOC and OC concentrations were inversely correlated with %body fat (r = -0.319, P = 0.007; r = -0.321, P = 0.006, respectively). Furthermore, multiple linear regression analyses were performed to determine whether or not serum ucOC or OC concentrations were factors associated with %body fat. Serum ucOC and OC concentrations remained significant factors even after adjusting for gender, HbA1c, body weight-adjusted total daily dose of insulin and duration of diabetes (β = -0.260, P = 0.027; β = -0.254, P = 0.031, respectively). However, serum ucOC and OC concentrations were not correlated with serum adiponectin or free-testosterone concentrations, muscle strength or dose of exogenous insulin. In conclusion, our study demonstrates the inverse correlation between serum ucOC or OC concentrations and body fat in patients with type 1 diabetes.
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Affiliation(s)
- Yuichi Takashi
- Diabetes Therapeutics and Research Center, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Masashi Ishizu
- Diabetes Therapeutics and Research Center, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
- Department of Hematology, Endocrinology and Metabolism, Tokushima University Graduate School of Biomedical Sciences, Tokushima, Japan
| | - Hiroyasu Mori
- Diabetes Therapeutics and Research Center, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Kazuyuki Miyashita
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Fumie Sakamoto
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Naoto Katakami
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Taka-aki Matsuoka
- Department of Metabolic Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tetsuyuki Yasuda
- Department of Diabetes and Endocrinology, Osaka Police Hospital, Osaka, Japan
| | - Seiichi Hashida
- Institute for Health Sciences, Tokushima Bunri University, Tokushima, Japan
| | - Munehide Matsuhisa
- Diabetes Therapeutics and Research Center, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
- * E-mail:
| | - Akio Kuroda
- Diabetes Therapeutics and Research Center, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
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Ren Z, Sun W, Liu Y, Li Z, Han D, Cheng X, Yan J, Yang X. Dynamics of serum phosphorus, calcium, and hormones during egg laying cycle in Hy-Line Brown laying hens. Poult Sci 2019; 98:2193-2200. [DOI: 10.3382/ps/pey572] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 12/05/2018] [Indexed: 12/14/2022] Open
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238
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Faye PA, Poumeaud F, Miressi F, Lia AS, Demiot C, Magy L, Favreau F, Sturtz FG. Focus on 1,25-Dihydroxyvitamin D3 in the Peripheral Nervous System. Front Neurosci 2019; 13:348. [PMID: 31031586 PMCID: PMC6474301 DOI: 10.3389/fnins.2019.00348] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 03/26/2019] [Indexed: 12/13/2022] Open
Abstract
In this review, we draw attention to the roles of calcitriol (1,25-dihydroxyvitamin D3) in the trophicity of the peripheral nervous system. Calcitriol has long been known to be crucial in phosphocalcium homeostasis. However, recent discoveries concerning its involvement in the immune system, anti-cancer defenses, and central nervous system development suggest a more pleiotropic role than previously thought. Several studies have highlighted the impact of calcitriol deficiency as a promoting factor of various central neurological diseases, such as multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. Based on these findings and recent publications, a greater role for calcitriol may be envisioned in the peripheral nervous system. Indeed, calcitriol is involved in myelination, axonal homogeneity of peripheral nerves, and neuronal-cell differentiation. This may have useful clinical consequences, as calcitriol supplementation may be a simple means to avoid the onset and/or development of peripheral nervous-system disorders.
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Affiliation(s)
- Pierre Antoine Faye
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
- Department of Biochemistry and Molecular Genetics, University Hospital of Limoges, Limoges, France
| | - François Poumeaud
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
| | - Federica Miressi
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
| | - Anne Sophie Lia
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
- Department of Biochemistry and Molecular Genetics, University Hospital of Limoges, Limoges, France
| | - Claire Demiot
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
| | - Laurent Magy
- CHU de Limoges, Reference Center for Rare Peripheral Neuropathies, Department of Neurology, Limoges, France
| | - Frédéric Favreau
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
- Department of Biochemistry and Molecular Genetics, University Hospital of Limoges, Limoges, France
| | - Franck G. Sturtz
- EA 6309, Myelin Maintenance and Peripheral Neuropathies, Faculties of Medicine and Pharmacy, University of Limoges, Limoges, France
- Department of Biochemistry and Molecular Genetics, University Hospital of Limoges, Limoges, France
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239
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Muro Bushart N, Tharun L, Oheim R, Paech A, Kiene J. Tumorinduzierte Osteomalazie, verursacht durch ein FGF23-sezernierendes Myoperizytom. DER ORTHOPADE 2019; 49:1-9. [DOI: 10.1007/s00132-019-03719-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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240
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Horvat-Gordon M, Hadley JA, Ghanem K, Leach RM. Lack of a relationship between plasma fibroblast growth factor-23 and phosphate utilization in young chicks. Poult Sci 2019; 98:1762-1765. [PMID: 30407587 DOI: 10.3382/ps/pey507] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/15/2018] [Indexed: 01/18/2023] Open
Abstract
Fibroblast growth factor 23 (FGF-23) is proposed to be the hormone that controls phosphate (P) homeostasis in chickens. This study was initiated to investigate the effect of feeding young chicks diets that were either adequate (0.45%) or marginal (0.25%) in available P content on plasma FGF-23 levels. The dietary level of available P significantly (P ≤ 0.05) affected bone mineralization and bone length, but was without effect (P > 0.05) on growth rate and circulating FGF-23 concentrations. Substantial individual variation in bone mineralization and plasma FGF-23 levels was observed, and the correlation between these two variables was non-significant (P > 0.05). This suggested that there was no alteration in FGF-23 activity in response to suboptimal dietary P intake. The relationship of these observations to studies on the immunosuppression of FGF-23 activity is subsequentlydiscussed.
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Affiliation(s)
- Maria Horvat-Gordon
- Department of Animal Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jill A Hadley
- Department of Animal Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Kahina Ghanem
- Department of Animal Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Roland M Leach
- Department of Animal Science, The Pennsylvania State University, University Park, PA 16802, USA
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241
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Srikanth K, Srivaths PR, Shah S. An 8-year-old with genu valgum: Answers. Pediatr Nephrol 2019; 34:621-624. [PMID: 30259113 DOI: 10.1007/s00467-018-4090-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/06/2018] [Accepted: 09/10/2018] [Indexed: 10/28/2022]
Affiliation(s)
| | - Poyyapakkam R Srivaths
- Renal Section, Department of Pediatrics, Baylor College of Medicine, 1102 Bates St, Suite 245, Houston, TX, 77030, USA
| | - Shweta Shah
- Renal Section, Department of Pediatrics, Baylor College of Medicine, 1102 Bates St, Suite 245, Houston, TX, 77030, USA.
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242
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Li W, Tan L, Li X, Zhang X, Wu X, Chen H, Hu L, Wang X, Luo X, Wang F, Xu C, Chen Q, Jin R, Wang QK. Identification of a p.Trp403* nonsense variant in PHEX causing X-linked hypophosphatemia by inhibiting p38 MAPK signaling. Hum Mutat 2019; 40:879-885. [PMID: 30920082 DOI: 10.1002/humu.23743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/01/2019] [Accepted: 03/06/2019] [Indexed: 11/08/2022]
Abstract
X-linked hypophosphatemia (XLH) is the most common hereditary rickets, caused by mutations in PHEX encoding the phosphate regulating endopeptidase homolog X-linked. Here, we report a nonsense variant in exon 11 of PHEX (c.1209G>A p.Trp403*) cosegregating with XLH in a Chinese family with a LOD score of 2.70. Real-time reverse transcription polymerase chain reaction analysis demonstrated that p.Trp403* variant did not cause nonsense-mediated mRNA decay (NMD), but significantly increased the expression level of FGF23 mRNA in the patients. Interestingly, p.Trp403* significantly reduced phosphorylation of p38 mitogen-activated protein kinase (MAPK) but not ERK1/2. Moreover, overexpression of FGF23 significantly decreased phosphorylation of p38 MAPK, whereas knockdown of FGF23 by siRNA significantly increased phosphorylation of p38 MAPK. These data suggest that p.Trp403* may not function via an NMD mechanism, and instead causes XLH via a novel signaling mechanism involving PHEX, FGF23, and p38 MAPK. This finding provides important insights into genetic and molecular mechanisms for the pathogenesis of XLH.
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Affiliation(s)
- Wei Li
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology and Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Lingfang Tan
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xin Li
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaoyu Zhang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology and Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xiaoyan Wu
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hongbo Chen
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Lihua Hu
- Department of Clinical Laboratory, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaobei Wang
- Department of Clinical Laboratory, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoping Luo
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fan Wang
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.,Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio.,Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Chengqi Xu
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology and Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qiuyun Chen
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.,Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio.,Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio
| | - Runming Jin
- Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Qing K Wang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology and Center for Human Genome Research, Huazhong University of Science and Technology, Wuhan, Hubei, China.,Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio.,Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, Ohio.,Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio
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243
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van Vuren AJ, Gaillard CAJM, Eisenga MF, van Wijk R, van Beers EJ. The EPO-FGF23 Signaling Pathway in Erythroid Progenitor Cells: Opening a New Area of Research. Front Physiol 2019; 10:304. [PMID: 30971944 PMCID: PMC6443968 DOI: 10.3389/fphys.2019.00304] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 03/07/2019] [Indexed: 12/14/2022] Open
Abstract
We provide an overview of the evidence for an erythropoietin-fibroblast growth factor 23 (FGF23) signaling pathway directly influencing erythroid cells in the bone marrow. We outline its importance for red blood cell production, which might add, among others, to the understanding of bone marrow responses to endogenous erythropoietin in rare hereditary anemias. FGF23 is a hormone that is mainly known as the core regulator of phosphate and vitamin D metabolism and it has been recognized as an important regulator of bone mineralization. Osseous tissue has been regarded as the major source of FGF23. Interestingly, erythroid progenitor cells highly express FGF23 protein and carry the FGF receptor. This implies that erythroid progenitor cells could be a prime target in FGF23 biology. FGF23 is formed as an intact, biologically active protein (iFGF23) and proteolytic cleavage results in the formation of the presumed inactive C-terminal tail of FGF23 (cFGF23). FGF23-knockout or injection of an iFGF23 blocking peptide in mice results in increased erythropoiesis, reduced erythroid cell apoptosis and elevated renal and bone marrow erythropoietin mRNA expression with increased levels of circulating erythropoietin. By competitive inhibition, a relative increase in cFGF23 compared to iFGF23 results in reduced FGF23 receptor signaling and mimics the positive effects of FGF23-knockout or iFGF23 blocking peptide. Injection of recombinant erythropoietin increases FGF23 mRNA expression in the bone marrow with a concomitant increase in circulating FGF23 protein. However, erythropoietin also augments iFGF23 cleavage, thereby decreasing the iFGF23 to cFGF23 ratio. Therefore, the net result of erythropoietin is a reduction of iFGF23 to cFGF23 ratio, which inhibits the effects of iFGF23 on erythropoiesis and erythropoietin production. Elucidation of the EPO-FGF23 signaling pathway and its downstream signaling in hereditary anemias with chronic hemolysis or ineffective erythropoiesis adds to the understanding of the pathophysiology of these diseases and its complications; in addition, it provides promising new targets for treatment downstream of erythropoietin in the signaling cascade.
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Affiliation(s)
- Annelies J van Vuren
- Van Creveldkliniek, Department of Internal Medicine and Dermatology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Carlo A J M Gaillard
- Department of Internal Medicine and Dermatology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Michele F Eisenga
- Department of Internal Medicine, Division of Nephrology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Richard van Wijk
- Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Eduard J van Beers
- Van Creveldkliniek, Department of Internal Medicine and Dermatology, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
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244
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FGF-23 Deficiency Impairs Hippocampal-Dependent Cognitive Function. eNeuro 2019; 6:eN-NRS-0469-18. [PMID: 30911673 PMCID: PMC6430630 DOI: 10.1523/eneuro.0469-18.2019] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 02/11/2019] [Accepted: 02/13/2019] [Indexed: 01/05/2023] Open
Abstract
Fibroblast growth factor receptor (FGFR) and α-Klotho transduce FGF-23 signaling in renal tubules to maintain systemic phosphate/vitamin D homeostasis. Mice deficient for either the ligand, FGF-23, or the co-receptor, Klotho, are phenocopies with both showing rapid and premature development of multiple aging-like abnormalities. Such similarity in phenotype, suggests that FGF-23 and Klotho have co-dependent systemic functions. Recent reports revealed inverse central nervous system (CNS) effects of Klotho deficiency or Klotho overexpression on hippocampal synaptic, neurogenic, and cognitive functions. However, it is unknown whether FGF-23 deficiency effects function of the hippocampus. We report that, similar to Klotho-deficient mice, FGF-23-deficient mice develop dose-dependent, hippocampal-dependent cognitive impairment. However, FGF-23-deficient brains had no gross structural or developmental defects, no change in hippocampal synaptic plasticity, and only minor impairment to postnatal hippocampal neurogenesis. Together, these data provide evidence that FGF-23 deficiency impairs hippocampal-dependent cognition but otherwise results in a brain phenotype that is distinct from the KL-deficient mouse.
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245
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Autosomal Dominant Hypophosphatemic Rickets Presenting in a Phenotypically Normal Adult Female. Case Rep Endocrinol 2019; 2019:8917519. [PMID: 30949368 PMCID: PMC6425306 DOI: 10.1155/2019/8917519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 01/06/2019] [Accepted: 02/17/2019] [Indexed: 02/07/2023] Open
Abstract
We describe a presentation of Autosomal Dominant Hypophosphatemic Rickets (ADHR) in a 22-year-old female with normal pubertal growth and development and a negative family history in first-degree relatives. The patient presented with a 2-year history of upper and lower extremity proximal muscle pain and weakness and bilateral femoral neck and pubic bone insufficiency fractures. She had a normal serum calcium but a low phosphate as well as 25-hydroxyvitamin D (25(OH)D) levels leading initially to a diagnosis of osteomalacia. Urine phosphate reabsorption was low confirming a phosphate wasting disorder. She had an elevated Fibroblast Growth Factor 23 (FGF23) level. After Tumor-Induced Osteomalacia was ruled out by extensive imaging, she was sent for genetic testing for hereditary rickets which showed a previously reported missense variant in FGF23. Subsequently, she found out that her father's maternal aunt and grandfather had ‘bone disorder' and were wheelchair-bound in adulthood. After replenishment of vitamin D, treatment with calcitriol and phosphate leads to complete resolution of patient's symptoms and laboratory abnormalities.
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246
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Pettifor JM. Hope for patients with X-linked hypophosphataemia? Lancet Diabetes Endocrinol 2019; 7:163-165. [PMID: 30638857 DOI: 10.1016/s2213-8587(19)30004-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 01/02/2019] [Indexed: 11/18/2022]
Affiliation(s)
- John M Pettifor
- SAMRC/Wits Developmental Pathways for Health Research Unit, Department of Paediatrics, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg 2050, South Africa.
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247
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Tumour-induced osteomalacia: A case report of craniofacial localization. OTOLARYNGOLOGY CASE REPORTS 2019. [DOI: 10.1016/j.xocr.2019.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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248
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Abstract
PURPOSE OF REVIEW The phosphaturic hormone FGF23 is produced primarily in osteoblasts/osteocytes and is known to respond to increases in serum phosphate and 1,25(OH)2 vitamin D (1,25D). Novel regulators of FGF23 were recently identified, and may help explain the pathophysiologies of several diseases. This review will focus on recent studies examining the synthesis and actions of FGF23. RECENT FINDINGS The synthesis of FGF23 in response to 1,25D is similar to other steroid hormone targets, but the cellular responses to phosphate remain largely unknown. The activity of intracellular processing genes control FGF23 glycosylation and phosphorylation, providing critical functions in determining the serum levels of bioactive FGF23. The actions of FGF23 largely occur through its co-receptor αKlotho (KL) under normal circumstances, but FGF23 has KL-independent activity during situations of high concentrations. SUMMARY Recent work regarding FGF23 synthesis and bioactivity, as well as considerations for diseases of altered phosphate balance will be reviewed.
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Affiliation(s)
- Megan L Noonan
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Kenneth E White
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN, USA
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249
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Beck-Nielsen SS, Mughal Z, Haffner D, Nilsson O, Levtchenko E, Ariceta G, de Lucas Collantes C, Schnabel D, Jandhyala R, Mäkitie O. FGF23 and its role in X-linked hypophosphatemia-related morbidity. Orphanet J Rare Dis 2019; 14:58. [PMID: 30808384 PMCID: PMC6390548 DOI: 10.1186/s13023-019-1014-8] [Citation(s) in RCA: 143] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/30/2019] [Indexed: 12/29/2022] Open
Abstract
Background X-linked hypophosphatemia (XLH) is an inherited disease of phosphate metabolism in which inactivating mutations of the Phosphate Regulating Endopeptidase Homolog, X-Linked (PHEX) gene lead to local and systemic effects including impaired growth, rickets, osteomalacia, bone abnormalities, bone pain, spontaneous dental abscesses, hearing difficulties, enthesopathy, osteoarthritis, and muscular dysfunction. Patients with XLH present with elevated levels of fibroblast growth factor 23 (FGF23), which is thought to mediate many of the aforementioned manifestations of the disease. Elevated FGF23 has also been observed in many other diseases of hypophosphatemia, and a range of animal models have been developed to study these diseases, yet the role of FGF23 in the pathophysiology of XLH is incompletely understood. Methods The role of FGF23 in the pathophysiology of XLH is here reviewed by describing what is known about phenotypes associated with various PHEX mutations, animal models of XLH, and non-nutritional diseases of hypophosphatemia, and by presenting molecular pathways that have been proposed to contribute to manifestations of XLH. Results The pathophysiology of XLH is complex, involving a range of molecular pathways that variously contribute to different manifestations of the disease. Hypophosphatemia due to elevated FGF23 is the most obvious contributor, however localised fluctuations in tissue non-specific alkaline phosphatase (TNAP), pyrophosphate, calcitriol and direct effects of FGF23 have been observed to be associated with certain manifestations. Conclusions By describing what is known about these pathways, this review highlights key areas for future research that would contribute to the understanding and clinical treatment of non-nutritional diseases of hypophosphatemia, particularly XLH.
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Affiliation(s)
| | - Zulf Mughal
- Royal Manchester Children's Hospital, Manchester, UK
| | | | - Ola Nilsson
- Karolinska Institutet, Stockholm, Sweden and Örebro University, Örebro, Sweden
| | | | - Gema Ariceta
- Hospital Universitario Materno-Infantil Vall d'Hebron, Universitat Autonoma de Barcelona, Barcelona, Spain
| | | | - Dirk Schnabel
- University Children's Hospital of Berlin, Berlin, Germany
| | | | - Outi Mäkitie
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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250
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Clinkenbeard EL, Noonan ML, Thomas JC, Ni P, Hum JM, Aref M, Swallow EA, Moe SM, Allen MR, White KE. Increased FGF23 protects against detrimental cardio-renal consequences during elevated blood phosphate in CKD. JCI Insight 2019; 4:123817. [PMID: 30830862 DOI: 10.1172/jci.insight.123817] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 01/14/2019] [Indexed: 12/23/2022] Open
Abstract
The phosphaturic hormone FGF23 is elevated in chronic kidney disease (CKD). The risk of premature death is substantially higher in the CKD patient population, with cardiovascular disease (CVD) as the leading mortality cause at all stages of CKD. Elevated FGF23 in CKD has been associated with increased odds for all-cause mortality; however, whether FGF23 is associated with positive adaptation in CKD is unknown. To test the role of FGF23 in CKD phenotypes, a late osteoblast/osteocyte conditional flox-Fgf23 mouse (Fgf23fl/fl/Dmp1-Cre+/-) was placed on an adenine-containing diet to induce CKD. Serum analysis showed casein-fed Cre+ mice had significantly higher serum phosphate and blood urea nitrogen (BUN) versus casein diet and Cre- genotype controls. Adenine significantly induced serum intact FGF23 in the Cre- mice over casein-fed mice, whereas Cre+ mice on adenine had 90% reduction in serum intact FGF23 and C-terminal FGF23 as well as bone Fgf23 mRNA. Parathyroid hormone was significantly elevated in mice fed adenine diet regardless of genotype, which significantly enhanced midshaft cortical porosity. Echocardiographs of the adenine-fed Cre+ hearts revealed profound aortic calcification and cardiac hypertrophy versus diet and genotype controls. Thus, these studies demonstrate that increased bone FGF23, although associated with poor outcomes in CKD, is necessary to protect against the cardio-renal consequences of elevated tissue phosphate.
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Affiliation(s)
| | | | | | - Pu Ni
- Department of Medical and Molecular Genetics
| | - Julia M Hum
- Department of Medical and Molecular Genetics
| | | | | | - Sharon M Moe
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
| | | | - Kenneth E White
- Department of Medical and Molecular Genetics.,Department of Anatomy and Cell Biology, and
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