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Akoa DM, Hélary C, Foda A, Chaussain C, Poliard A, Coradin T. Silicon impacts collagen remodelling and mineralization by human dental pulp stem cells in 3D pulp-like matrices. Dent Mater 2024:S0109-5641(24)00179-9. [PMID: 38908960 DOI: 10.1016/j.dental.2024.06.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 06/14/2024] [Accepted: 06/14/2024] [Indexed: 06/24/2024]
Abstract
OBJECTIVES Silicon-releasing biomaterials are widely used in the field of dentistry. However, unlike bone, very little is known about the role of silicon on dental tissue formation and repair. This study investigates the influence of silicic acid on the survival, differentiation and mineralizing ability of human dental pulp stem cells (hDPSCs) in 3D pulp-like environments METHODS: Dense type I collagen hydrogels seeded with hDPSCs were cultured over 4 weeks in the presence of silicic acid at physiological (10 μM) and supraphysiological (100 μM) concentrations. Cell viability and proliferation were studied by Alamar Blue and live/dead staining. The collagen network was investigated using second harmonic generation imaging. Mineral deposition was monitored by histology and scanning electron microscopy. Gene expression of mineralization- and matrix remodeling-associated proteins was studied by qPCR. RESULTS Presence of silicic acid did not show any significant influence on cell survival, metabolic activity and gene expression of key mineralization-related proteins (ALP, OCN, BSP). However, it induced enhanced cell clustering and delayed expression of matrix remodeling-associated proteins (MMP13, Col I). OPN expression and mineral deposition were inhibited at 100 μM. It could be inferred that silicic acid has no direct cellular effect but rather interacts with the collagen network, leading to a modification of the cell-matrix interface. SIGNIFICANCE Our results offer advanced insights on the possible role of silicic acid, as released by pulp capping calcium silicates biomaterials, in reparative dentine formation. More globally, these results interrogate the possible role of Si in pulp pathophysiology.
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Affiliation(s)
- Daline Mbitta Akoa
- Sorbonne Université, CNRS, Laboratoire de Chimie de la Matière Condensée de Paris, Paris, France
| | - Christophe Hélary
- Sorbonne Université, CNRS, Laboratoire de Chimie de la Matière Condensée de Paris, Paris, France
| | - Asmaa Foda
- Université de Paris Cité, UR2496 Pathologies, Imagerie et Biothérapies Orofaciales, FHU-DDS-net, Dental School, Montrouge, France
| | - Catherine Chaussain
- Université de Paris Cité, UR2496 Pathologies, Imagerie et Biothérapies Orofaciales, FHU-DDS-net, Dental School, Montrouge, France; AP-HP Service de médecine bucco-dentaire, Hôpital Bretonneau, Paris, France
| | - Anne Poliard
- Université de Paris Cité, UR2496 Pathologies, Imagerie et Biothérapies Orofaciales, FHU-DDS-net, Dental School, Montrouge, France
| | - Thibaud Coradin
- Sorbonne Université, CNRS, Laboratoire de Chimie de la Matière Condensée de Paris, Paris, France.
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Arhar A, Pavlič A, Hočevar L. Characteristics of oral health of patients with X-linked hypophosphatemia: case reports and literature review. BDJ Open 2024; 10:42. [PMID: 38821917 PMCID: PMC11143263 DOI: 10.1038/s41405-024-00223-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/22/2024] [Accepted: 04/25/2024] [Indexed: 06/02/2024] Open
Abstract
BACKGROUND Oral health is impaired in X-linked hypophosphatemia (XLH), resulting in delayed dental development, malocclusion, and radiographic abnormalities. This study investigates the oral manifestations in Slovenian XLH patients, focusing on enamel and dentin abnormalities and a literature review of spontaneous periapical abscesses in XLH cases. OBJECTIVES To report XLH patients with specific oral signs and symptoms, histological analysis of affected teeth, and review of reported cases of XLH patients with spontaneous periapical abscesses. METHODS Case reports: Seven XLH patients from the National Registry of Patients with Rare Diseases underwent a detailed oral examination, including X-ray reviews. The patients who were expected to have tooth exfoliation or extraction were asked to donate their teeth for histological analysis by scanning electron microscopy. LITERATURE SEARCH A literature search of four electronic databases and a manual bibliography search aimed to identify documented cases of XLH with periapical abscesses up to January 21, 2024. Inclusion criteria were confirmed XLH patients with periapical abscesses in English peer-reviewed publications. RESULTS Tooth samples from three XLH patients showed reduced dentin mineralisation, affecting one-third to one-half of the outer dentin. Inadequate mineralisation, uneven dentin tubules, and cracks and chipping in the enamel were observed, indicating mineralisation deviations. Similar cracks extended into the dentin and were also present in the root of the examined tooth. Based on the content of the 75 items identified in the search, spontaneous abscesses are not uncommon in patients with XLH. CONCLUSIONS XLH significantly affects patients' lives and requires lifelong treatment. Dental examinations consistently revealed oral problems, including malocclusion. Histological analysis confirmed structural changes, especially in the dentin. Despite continued treatment, XLH patients may have an increased risk of oral pathologies. Further research is needed to understand the impact of XLH and its treatment on dental health.
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Affiliation(s)
- Ana Arhar
- Department of Paediatric and Preventive Dentistry, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, Ljubljana, Slovenia
| | - Alenka Pavlič
- Department of Paediatric and Preventive Dentistry, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, Ljubljana, Slovenia
- Department of Paediatric and Preventive Dentistry, University Medical Centre Ljubljana, Zaloška 2, Ljubljana, Slovenia
| | - Luka Hočevar
- Department of Paediatric and Preventive Dentistry, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, Ljubljana, Slovenia.
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Nakanishi T, Yamazaki M, Tachikawa K, Ueta A, Kawai M, Ozono K, Michigami T. Complex intrinsic abnormalities in osteoblast lineage cells of X-linked hypophosphatemia: Analysis of human iPS cell models generated by CRISPR/Cas9-mediated gene ablation. Bone 2024; 181:117044. [PMID: 38331306 DOI: 10.1016/j.bone.2024.117044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 01/04/2024] [Accepted: 02/05/2024] [Indexed: 02/10/2024]
Abstract
X-linked hypophosphatemia (XLH) is caused by inactivating variants of the phosphate regulating endopeptidase homolog X-linked (PHEX) gene. Although the overproduction of fibroblast growth factor 23 (FGF23) is responsible for hypophosphatemia and impaired vitamin D metabolism, the pathogenesis of XLH remains unclear. We herein generated PHEX-knockout (KO) human induced pluripotent stem (iPS) cells by applying CRISPR/Cas9-mediated gene ablation to an iPS clone derived from a healthy male, and analyzed PHEX-KO iPS cells with deletions extending from exons 1 to 3 and frameshifts by inducing them to differentiate into the osteoblast lineage. We confirmed the increased production of FGF23 in osteoblast lineage cells differentiated from PHEX-KO iPS cells. In vitro mineralization was enhanced in osteoblast lineage cells from PHEX-KO iPS cells than in those from isogenic control iPS cells, which reminded us of high bone mineral density and enthesopathy in patients with XLH. The extracellular level of pyrophosphate (PPi), an inhibitor of mineralization, was elevated, and this increase appeared to be partly due to the reduced activity of tissue non-specific alkaline phosphatase (TNSALP). Osteoblast lineage cells derived from PHEX-KO iPS cells also showed the increased expression of multiple molecules such as dentine matrix protein 1, osteopontin, RUNX2, FGF receptor 1 and early growth response 1. This gene dysregulation was similar to that in the osteoblasts/osteocytes of Phex-deficient Hyp mice, suggesting that common pathogenic mechanisms are shared between human XLH and Hyp mice. Moreover, we found that the phosphorylation of CREB was markedly enhanced in osteoblast lineage cells derived from PHEX-KO iPS cells, which appeared to be associated with the up-regulation of the parathyroid hormone related protein gene. PHEX deficiency also affected the response of the ALPL gene encoding TNSALP to extracellular Pi. Collectively, these results indicate that complex intrinsic abnormalities in osteoblasts/osteocytes underlie the pathogenesis of human XLH.
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Affiliation(s)
- Tatsuro Nakanishi
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Izumi, Osaka 594-1101, Japan; Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan
| | - Miwa Yamazaki
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Izumi, Osaka 594-1101, Japan
| | - Kanako Tachikawa
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Izumi, Osaka 594-1101, Japan
| | - Ayu Ueta
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Izumi, Osaka 594-1101, Japan; 1st Department of Oral and Maxillofacial Surgery, Osaka University Graduate School of Dentistry, Suita, Osaka 565-0871, Japan
| | - Masanobu Kawai
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Izumi, Osaka 594-1101, Japan
| | | | - Toshimi Michigami
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Izumi, Osaka 594-1101, Japan.
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Abdullah A, Wuersching SN, Kollmuss M, Poxleitner P, Dewenter I, Brandenburg LS, Steybe D, Fegg FN, Smolka W, Otto S, Obermeier KT. X-Linked Hypophosphatemia: Does Targeted Therapy Modify Dental Impairment? J Clin Med 2023; 12:7546. [PMID: 38137614 PMCID: PMC10744150 DOI: 10.3390/jcm12247546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/22/2023] [Accepted: 12/04/2023] [Indexed: 12/24/2023] Open
Abstract
X-linked hypophosphatemia is a rare, hereditary disorder that significant influences teeth and alveolar bone. The first clinical sign leading to the diagnosis of X-linked hypophosphatemia is often dental impairment with dental abscesses and dentin mineralization defects. Genetic analysis helped find the responsible gene and therefore opened up new ways of therapeutically managing X-linked hypophosphatemia. The human monoclonal antibody Burosumab represents a milestone in the targeted therapy of this hereditary disease by directly addressing its pathophysiology. Targeted therapy has been shown to improve skeletal impairment, pain, and phosphate metabolism. However, the influence of this new therapy on dental impairment has only been addressed in a few recent studies with varying results. Therefore, in this review, we aim to summarize the dental phenotype and analyze the different treatment modalities with a focus on dental impairment.
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Affiliation(s)
- Anusha Abdullah
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Sabina Noreen Wuersching
- Department of Conservative Dentistry and Periodontology, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Maximilian Kollmuss
- Department of Conservative Dentistry and Periodontology, University Hospital, LMU Munich, Goethestrasse 70, 80336 Munich, Germany
| | - Philipp Poxleitner
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Ina Dewenter
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Leonard Simon Brandenburg
- Medical Center—University of Freiburg, Center for Dental Medicine, Department of Oral and Maxillofacial Surgery, Faculty of Medicine, University of Freiburg, Hugstetter Str. 55, 79106 Freiburg, Germany
| | - David Steybe
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Florian Nepomuk Fegg
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Wenko Smolka
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Sven Otto
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
| | - Katharina Theresa Obermeier
- Department of Oral and Maxillofacial Surgery and Facial Plastic Surgery, Ludwig Maximilians University, 80337 Munich, Germany
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Dental manifestations and treatment of hypophosphatemic rickets: A case report and review of literature. BDJ Open 2023; 9:2. [PMID: 36717535 PMCID: PMC9886973 DOI: 10.1038/s41405-023-00129-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/29/2022] [Accepted: 01/02/2023] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND The treatment and management of patients suffering from hypophosphatemic rickets (HR) remain a major challenge for dental practitioners and affected patients. OBJECTIVES To report a case of HR presenting with specific dental findings and to review the dental manifestations and treatment of HR patients. METHODS Case: A 32-year-old male presented with multiple dental abscesses and short stature. A thorough history was taken followed by clinical oral examination, and relevant radiological investigation was done. Literature research: In 2020, electronic literature searches were carried out in PubMed and complemented by a careful assessment of the reference lists of the identified relevant papers. Articles and reports fulfilled the inclusion criteria: indexed reviews, case series and case reports in English and restricted to human studies were considered. RESULTS The intraoral examination revealed multiple dental abscesses and general periodontal disease; the radiographic examination showed poorly defined lamina dura, large pulp chambers and periapical lesions. Based on the contents of the 43 articles identified in the search, the current knowledge of dental manifestations, treatment and management of HR was summarized. CONCLUSIONS As HR is a multisystem disease, multidisciplinary care is needed. By summarizing current evidences, we proposed an evidence-based dental management and provided recommendations on diagnosis and treatment of the disease. It is of profound clinical significance to acquire knowledge of the dental manifestations and provide optimal treatment options for patients.
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Larsson A, Regnstrand T, Skott P, Mäkitie O, Björnsdottir S, Garming-Legert K. Dental health of patients with X-linked hypophosphatemia: A controlled study. FRONTIERS IN ORAL HEALTH 2023; 4:1087761. [PMID: 37026091 PMCID: PMC10070686 DOI: 10.3389/froh.2023.1087761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 02/28/2023] [Indexed: 04/08/2023] Open
Abstract
Objective The present study compared the dental health of patients with X-linked hypophosphatemia (XLH) with healthy age- and gender-matched controls to increase our knowledge of the impact of XLH on oral health. Materials and methods Twenty-two adult patients with XLH in the Stockholm region of Sweden were referred to the Department of Orofacial Medicine at Karolinska Institutet for an extended clinical and radiological examination. Pre-existing radiologic examinations of 44 healthy age- and gender-matched controls were retrieved from the Department of Oral Radiology, at Karolinska Institutet. Results The 22 patients with XLH (15 females, median age 38 years, range 20-71; 7 males, median age 49 years, range 24-67) had a significantly higher number of root-filled teeth compared to healthy controls (p = .001). In the XLH group, females had significantly better oral health than males, especially concerning endodontic and cariological status (p's = .01 and .02, respectively). Periodontal status differed non-significantly between the XLH and control groups. Conclusion Patients with XLH had a significantly lower oral health status compared to a healthy population especially concerning endodontic conditions. Male patients with XLH had a higher risk of poor oral health compared to female patients with XLH.
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Affiliation(s)
- Amila Larsson
- Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
- Public Dental Health Service Stockholm AB, Stockholm, Sweden
- Correspondence: Amila Larsson
| | - Tobias Regnstrand
- Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Pia Skott
- Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
- Public Dental Health Service Stockholm AB, Stockholm, Sweden
| | - Outi Mäkitie
- Department of Pediatric Research, Children's Hospital, Pediatric Research Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
- Department of Clinical Genetics, Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
| | - Sigridur Björnsdottir
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
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Vitamin D and Phosphate Interactions in Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1362:37-46. [DOI: 10.1007/978-3-030-91623-7_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Brener R, Zeitlin L, Lebenthal Y, Brener A. Dental health of pediatric patients with X-linked hypophosphatemia (XLH) after three years of burosumab therapy. Front Endocrinol (Lausanne) 2022; 13:947814. [PMID: 36051396 PMCID: PMC9425915 DOI: 10.3389/fendo.2022.947814] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
An inactivating PHEX gene mutation with the resultant accumulation of several mineralization-inhibiting proteins (e.g., FGF23) causes skeletal and dental morbidity in X-linked hypophosphatemia (XLH). This prospective case-control study explored the effect of burosumab, an anti-FGF23 antibody, on dental health of children with XLH. Ten children (age 4.3-15 years) with XLH underwent burosumab treatment per protocol. Assessment of their dental status at treatment initiation and after 1 and 3 years of treatment included clinical, laboratory and radiographic evaluation of rickets and dentition. Orthopantomographic examinations of ten healthy sex- and age-matched controls were selected for comparison. Coronal and pulp dimensions of a selected permanent mandibular molar were measured with Planmeca Romexis® software. One year of treatment led to improvement of height z-score (p=0.019) and healing of the rickets (p<0.001) in the XLH patients, and those achievements were maintained after three years of treatment. Dental morphology of XLH patients, distinguished by increased pulp-coronal ratios compared to controls (p=0.002), remained larger after the first year of treatment (p<0.001) and did not attain the decrease expected with age after three years of treatment. Five patients had a history of recurrent dental abscesses, with three having undergone at least one episode during the year before burosumab initiation. One patient sustained recurrent abscesses throughout three years of treatment. The persistence of the unique dental morphology of XLH patients undergoing burosumab therapy, as evidenced by excessively larger pulp dimensions, supports the role of other PHEX gene-related local mineralization inhibitors, such as osteopontin, in the pathogenesis of dental morbidity.
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Affiliation(s)
- Rafi Brener
- The Endodontic Unit, Galilee College of Dental Sciences, Galilee Medical Center, Nahariya, Israel
- Azrieli Faculty of Medicine, Bar-Ilan University, Safed, Israel
| | - Leonid Zeitlin
- The Metabolic Bone Disease Unit, Dana-Dwek Children’s Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Yael Lebenthal
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Pediatric Endocrinology and Diabetes Unit, Dana-Dwek Children’s Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - Avivit Brener
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Pediatric Endocrinology and Diabetes Unit, Dana-Dwek Children’s Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- *Correspondence: Avivit Brener,
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Giannini S, Bianchi ML, Rendina D, Massoletti P, Lazzerini D, Brandi ML. Burden of disease and clinical targets in adult patients with X-linked hypophosphatemia. A comprehensive review. Osteoporos Int 2021; 32:1937-1949. [PMID: 34009447 PMCID: PMC8510985 DOI: 10.1007/s00198-021-05997-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 05/06/2021] [Indexed: 11/17/2022]
Abstract
UNLABELLED X-linked hypophosphataemia (XLH) is a lifelong condition. Despite the mounting clinical evidence highlighting the long-term multi-organ sequelae of chronic phosphate wasting and consequent hypophosphatemia over the lifetime and the morbidities associated with adult age, XLH is still perceived as a paediatric disease. INTRODUCTION Children who have XLH need to transition from paediatric to adult healthcare as young adults. While there is general agreement that all affected children should be treated (if the administration and tolerability of therapy can be adequately monitored), there is a lack of consensus regarding therapy in adults. METHODS To provide guidance in both diagnosis and treatment of adult XLH patients and promote better provision of care for this potentially underserved group of patients, we review the available clinical evidence and discuss the current challenges underlying the transition from childhood to adulthood care to develop appropriate management and follow-up patterns in adult XLH patients. RESULTS AND CONCLUSIONS Such a multi-systemic lifelong disease would demand that the multidisciplinary approach, successfully experienced in children, could be transitioned to adulthood care with an integration of specialized sub-disciplines to efficiently control musculoskeletal symptoms while optimizing patients' QoL. Overall, it would be desirable that transition to adulthood care could be a responsibility shared by the paediatric and adult XLH teams. Pharmacological management should require an adequate balance between the benefits derived from the treatment itself with complicated and long-term monitoring and the potential risks, as they may differ across age strata.
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Affiliation(s)
- S Giannini
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy.
| | - M L Bianchi
- Experimental Laboratory for Children's Bone Metabolism Research, Bone Metabolism Unit, Istituto Auxologico Italiano IRCCS, Milano, Italy
| | - D Rendina
- Department of Clinical Medicine and Surgery, Federico II University, Napoli, Italy
| | - P Massoletti
- Medical Affairs, Kyowa Kyrin, Basiglio, (MI), Italy
| | - D Lazzerini
- Medical Affairs, Kyowa Kyrin, Basiglio, (MI), Italy
| | - M L Brandi
- Metabolic Bone Diseases Unit, Department of Surgery and Translational Medicine, University of Firenze, Firenze, Italy
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Qin W, Wan QQ, Ma YX, Wang CY, Wan MC, Ma S, Wang YR, Wang WR, Gu JT, Tay FR, Niu LN. Manifestation and Mechanisms of Abnormal Mineralization in Teeth. ACS Biomater Sci Eng 2021; 9:1733-1756. [PMID: 34436861 DOI: 10.1021/acsbiomaterials.1c00592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Tooth biomineralization is a dynamic and complicated process influenced by local and systemic factors. Abnormal mineralization in teeth occurs when factors related to physiologic mineralization are altered during tooth formation and after tooth maturation, resulting in microscopic and macroscopic manifestations. The present Review provides timely information on the mechanisms and structural alterations of different forms of pathological tooth mineralization. A comprehensive study of these alterations benefits diagnosis and biomimetic treatment of abnormal mineralization in patients.
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Affiliation(s)
- Wen Qin
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Qian-Qian Wan
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Yu-Xuan Ma
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Chen-Yu Wang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Mei-Chen Wan
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Sai Ma
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Yi-Rong Wang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Wan-Rong Wang
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Jun-Ting Gu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
| | - Franklin R Tay
- College of Graduate Studies, Augusta University, Augusta, Georgia 30912, United States
| | - Li-Na Niu
- State Key Laboratory of Military Stomatology & National Clinical Research Center for Oral Diseases & Shaanxi Key Laboratory of Stomatology, Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University, Xi'an, Shaanxi 710032, P. R. China
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Marin A, Morales P, Jiménez M, Borja E, Ivanovic-Zuvic D, Collins MT, Florenzano P. Characterization of Oral Health Status in Chilean Patients with X-Linked Hypophosphatemia. Calcif Tissue Int 2021; 109:132-138. [PMID: 33839802 DOI: 10.1007/s00223-021-00841-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 03/18/2021] [Indexed: 01/22/2023]
Abstract
X-Linked Hypophosphatemia (XLH) is the most common cause of inherited hypophosphatemic rickets. Dental involvement, including spontaneous abscesses and/or fistulae, is an important part of the disease and has not been completely defined, especially in cohorts from developing countries. To describe oral health status in a cohort of Chilean patients with XLH and explore its correlation with biochemical presentation and treatment, we conducted a cross-sectional observational study of patients with PHEX mutation-confirmed XLH. All patients had an oral clinical exam, radiographic evaluation; clinical and biochemical data were obtained to determine their association with oral features. Twenty-six patients were included, 77% adults and 23% children. Most adults (89%) had past or current dental pulp pathology (abscesses and/or fistulae). Pulpal chamber enlargement and radiolucent apical lesions were common radiological features (94 and 74%, respectively). In children, abscess and/or fistulae were also common (33%). Caries index, which was determined by dmft/DMFT, was higher than the Chilean national average. Early and long-term therapy with phosphate and activated vitamin D was associated with lower carious index and attachment loss. XLH patients frequently present with high pulpal involvement and carious index. Conventional therapy was associated with lower carious index and attachment loss. These data highlight the importance of early and periodical dental care in order to prevent dental damage and assure a good quality of oral health for XLH patients.
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Affiliation(s)
- Alejandro Marin
- Faculty of Medicine, School of Dentistry, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pilar Morales
- Faculty of Medicine, School of Dentistry, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Macarena Jiménez
- Endocrinology Department, School of Medicine, Pontificia Universidad Católica de Chile, Av. Diagonal Paraguay 262, Cuarto piso, Santiago, Chile
| | - Eugenia Borja
- Faculty of Medicine, School of Dentistry, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Danisa Ivanovic-Zuvic
- Internal Medicine Department, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Michael T Collins
- Skeletal Disorders and Mineral Homeostasis Section, National Institutes of Dental and Craniofacial Research, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Pablo Florenzano
- Endocrinology Department, School of Medicine, Pontificia Universidad Católica de Chile, Av. Diagonal Paraguay 262, Cuarto piso, Santiago, Chile.
- Center for Translational Research in Endocrinology, CETREN-UC, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
- Skeletal Disorders and Mineral Homeostasis Section, National Institutes of Dental and Craniofacial Research, National Institutes of Health (NIH), Bethesda, MD, USA.
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12
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Cauliez A, Zhukouskaya VV, Hilliquin S, Sadoine J, Slimani L, Miceli-Richard C, Briot K, Linglart A, Chaussain C, Bardet C. Impact of Early Conventional Treatment on Adult Bone and Joints in a Murine Model of X-Linked Hypophosphatemia. Front Cell Dev Biol 2021; 8:591417. [PMID: 33681179 PMCID: PMC7930336 DOI: 10.3389/fcell.2020.591417] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 12/07/2020] [Indexed: 11/13/2022] Open
Abstract
X-linked hypophosphatemia (XLH) is the most common form of genetic rickets. Mainly diagnosed during childhood because of growth retardation and deformities of the lower limbs, the disease affects adults with early enthesopathies and joint structural damage that significantly alter patient quality of life. The conventional treatment, based on phosphorus supplementation and active vitamin D analogs, is commonly administered from early childhood to the end of growth; unfortunately, it does not allow complete recovery from skeletal damage. Despite adequate treatment during childhood, bone and joint complications occur in adults and become a dominant feature in the natural history of the disease. Our previous data showed that the Hyp mouse is a relevant model of XLH for studying early enthesophytes and joint structural damage. Here, we studied the effect of conventional treatment on the development of bone and joint alterations in this mouse model during growth and young adulthood. Mice were supplemented with oral phosphorus and calcitriol injections, following two timelines: (i) from weaning to 3 months of age and (ii) from 2 to 3 months to evaluate the effects of treatment on the development of early enthesophytes and joint alterations, and on changes in bone and joint deformities already present, respectively. We showed that early conventional treatment improved bone microarchitecture, and partially prevented bone and joint complications, but with no noticeable improvement in enthesophytes. In contrast, later administration had limited efficacy in ameliorating bone and joint alterations. Despite the improvement in bone microarchitecture, the conventional treatment, early or late, had no effect on osteoid accumulation. Our data underline the usefulness of the Hyp murine model for preclinical studies on skeletal and extraskeletal lesions. Although the early conventional treatment is important for the improvement of bone microarchitecture, the persistence of osteomalacia implies seeking new therapeutic strategies, in particular anti-FGF23 approach, in order to optimize the treatment of XLH.
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Affiliation(s)
- Axelle Cauliez
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France
| | - Volha V Zhukouskaya
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France.,INTEGRARE, Genethon, Inserm, Université d'Evry, Université Paris-Saclay, Evry, France.,Centre de référence des maladies rares du métabolisme du calcium et du phosphate, Plateforme d'expertise maladies rares Paris Saclay, filière OSCAR, EndoRare and BOND ERN, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France
| | - Stéphane Hilliquin
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France.,Department of Rheumatology, Cochin Hospital, Université de Paris, Paris, France
| | - Jérémy Sadoine
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France
| | - Lotfi Slimani
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France
| | | | - Karine Briot
- Centre de référence des maladies rares du métabolisme du calcium et du phosphate, Plateforme d'expertise maladies rares Paris Saclay, filière OSCAR, EndoRare and BOND ERN, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France.,Department of Rheumatology, Cochin Hospital, Université de Paris, Paris, France
| | - Agnès Linglart
- Centre de référence des maladies rares du métabolisme du calcium et du phosphate, Plateforme d'expertise maladies rares Paris Saclay, filière OSCAR, EndoRare and BOND ERN, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France.,Université Paris-Saclay, AP-HP, Service d'endocrinologie et diabète de l'enfant, Service de médecine des adolescents, Hôpital de Bicêtre, INSERM U1185, Le Kremlin-Bicêtre, France
| | - Catherine Chaussain
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France.,Centre de référence des maladies rares du métabolisme du calcium et du phosphate, Plateforme d'expertise maladies rares Paris Saclay, filière OSCAR, EndoRare and BOND ERN, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France.,AP-HP Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Dental Medicine Department, Bretonneau Hospital, GHN, Paris, France
| | - Claire Bardet
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies URP 2496 and FHU-DDS-Net, Dental School, and Plateforme d'Imagerie du Vivant (PIV), Montrouge, France
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13
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Robinson ME, AlQuorain H, Murshed M, Rauch F. Mineralized tissues in hypophosphatemic rickets. Pediatr Nephrol 2020; 35:1843-1854. [PMID: 31392510 DOI: 10.1007/s00467-019-04290-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/03/2019] [Accepted: 06/06/2019] [Indexed: 12/19/2022]
Abstract
Hypophosphatemic rickets is caused by renal phosphate wasting that is most commonly due to X-linked dominant mutations in PHEX. PHEX mutations cause hypophosphatemia indirectly, through the increased expression of fibroblast growth factor 23 (FGF23) by osteocytes. FGF23 decreases renal phosphate reabsorption and thereby increases phosphate excretion. The lack of phosphate leads to a mineralization defect at the level of growth plates (rickets), bone tissue (osteomalacia), and teeth, where the defect facilitates the formation of abscesses. The bone tissue immediately adjacent to osteocytes often remains unmineralized ("periosteocytic lesions"), highlighting the osteocyte defect in this disorder. Common clinical features of XLH include deformities of the lower extremities, short stature, enthesopathies, dental abscesses, as well as skull abnormalities such as craniosynostosis and Chiari I malformation. For the past four decades, XLH has been treated by oral phosphate supplementation and calcitriol, which improves rickets and osteomalacia and the dental manifestations, but often does not resolve all aspects of the mineralization defects. A newer treatment approach using inactivating FGF23 antibodies leads to more stable control of serum inorganic phosphorus levels and seems to heal rickets more reliably. However, the long-term benefits of FGF23 antibody treatment remain to be elucidated.
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Affiliation(s)
- Marie-Eve Robinson
- Shriners Hospital for Children and McGill University, 1003 Boulevard Decarie, Montreal, Québec, H4A 0A9, Canada
| | - Haitham AlQuorain
- Shriners Hospital for Children and McGill University, 1003 Boulevard Decarie, Montreal, Québec, H4A 0A9, Canada
| | - Monzur Murshed
- Shriners Hospital for Children and McGill University, 1003 Boulevard Decarie, Montreal, Québec, H4A 0A9, Canada
| | - Frank Rauch
- Shriners Hospital for Children and McGill University, 1003 Boulevard Decarie, Montreal, Québec, H4A 0A9, Canada.
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14
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Faraji-Bellée CA, Cauliez A, Salmon B, Fogel O, Zhukouskaya V, Benoit A, Schinke T, Roux C, Linglart A, Miceli-Richard C, Chaussain C, Briot K, Bardet C. Development of Enthesopathies and Joint Structural Damage in a Murine Model of X-Linked Hypophosphatemia. Front Cell Dev Biol 2020; 8:854. [PMID: 33072734 PMCID: PMC7536578 DOI: 10.3389/fcell.2020.00854] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 08/10/2020] [Indexed: 12/14/2022] Open
Abstract
X-linked hypophosphatemia (XLH) is characterized by rickets and osteomalacia, caused by inactivating mutations in the Phosphate-regulating endopeptidase homolog X-linked (PHEX) gene. With aging, adult patients develop paradoxical heterotopic calcifications of tendons and ligaments at their insertion sites (enthesophytes), and joint alterations. Understanding the progression of this structural damage that severely affects patients’ quality of life will help to improve the management of XLH. Here, we characterized the occurrence of enthesophytes and joint alterations through a 12 month in vivo micro-CT follow-up in the Hyp mouse, a murine model of XLH (n = 5 mice per group). Similar to adult patients with XLH, Hyp mice developed calcaneal enthesophytes, hip joint alterations, erosions of the sacroiliac joints and periarticular calcifications. These lesions were already present at month 3 and gradually worsened over time. In sharp contrast, no abnormalities were observed in control mice at early time points. Histological analyses confirmed the presence of bone erosions, calcifications and expansion of mineralizing enthesis fibrocartilage in Hyp mice and their absence in controls and suggested that new bone formation is driven by altered mechanical strain. Interestingly, despite a strong deformation of the curvature, none of the Hyp mice displayed enthesophyte at the spine. Peripheral enthesophytes and joint alterations develop at the early stages of the disease and gradually worsen overtime. Overall, our findings highlight the relevance of this preclinical model to test new therapies aiming to prevent bone and joint complications in XLH.
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Affiliation(s)
- Carole-Anne Faraji-Bellée
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies UR 2496, Dental School, Montrouge, France
| | - Axelle Cauliez
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies UR 2496, Dental School, Montrouge, France
| | - Benjamin Salmon
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies UR 2496, Dental School, Montrouge, France.,APHP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Dental Medicine Department, Bretonneau Hospital, Paris, France
| | - Olivier Fogel
- Department of Rheumatology, Cochin Hospital, Université de Paris, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, and Reference Center for Rare Genetic Bone Diseases, Cochin Hospital, Paris, France
| | - Volha Zhukouskaya
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies UR 2496, Dental School, Montrouge, France.,APHP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Sud Hospital, Le Kremlin Bicêtre, France
| | - Aurélie Benoit
- Université de Paris, URB2I, UR 4462, Dental School, Montrouge, France
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Christian Roux
- Department of Rheumatology, Cochin Hospital, Université de Paris, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, and Reference Center for Rare Genetic Bone Diseases, Cochin Hospital, Paris, France
| | - Agnès Linglart
- APHP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Sud Hospital, Le Kremlin Bicêtre, France.,APHP, Department of Endocrinology and Diabetology for Children, Bicêtre Paris Sud Hospital, Le Kremlin-Bicêtre, France.,Paris Sud - Paris Saclay University, Faculté de Médecine, Le Kremlin - Bicêtre, France
| | - Corinne Miceli-Richard
- Department of Rheumatology, Cochin Hospital, Université de Paris, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, and Reference Center for Rare Genetic Bone Diseases, Cochin Hospital, Paris, France
| | - Catherine Chaussain
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies UR 2496, Dental School, Montrouge, France.,APHP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Dental Medicine Department, Bretonneau Hospital, Paris, France.,APHP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Sud Hospital, Le Kremlin Bicêtre, France
| | - Karine Briot
- Department of Rheumatology, Cochin Hospital, Université de Paris, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, and Reference Center for Rare Genetic Bone Diseases, Cochin Hospital, Paris, France.,APHP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Sud Hospital, Le Kremlin Bicêtre, France
| | - Claire Bardet
- Université de Paris, Laboratory Orofacial Pathologies, Imaging and Biotherapies UR 2496, Dental School, Montrouge, France
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15
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Wato K, Okawa R, Matayoshi S, Ogaya Y, Nomura R, Nakano K. X-linked hypophosphatemia diagnosed after identification of dental symptoms. PEDIATRIC DENTAL JOURNAL 2020. [DOI: 10.1016/j.pdj.2020.06.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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16
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Fratzl-Zelman N, Gamsjaeger S, Blouin S, Kocijan R, Plasenzotti P, Rokidi S, Nawrot-Wawrzyniak K, Roetzer K, Uyanik G, Haeusler G, Shane E, Cohen A, Klaushofer K, Paschalis EP, Roschger P, Fratzl P, Zwerina J, Zwettler E. Alterations of bone material properties in adult patients with X-linked hypophosphatemia (XLH). J Struct Biol 2020; 211:107556. [PMID: 32619592 DOI: 10.1016/j.jsb.2020.107556] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 06/18/2020] [Accepted: 06/23/2020] [Indexed: 01/08/2023]
Abstract
X-linked hypophosphatemia (XLH) caused by PHEX mutations results in elevated serum FGF23 levels, renal phosphate wasting and low 1,25-dihydroxyvitamin D. The glycophosphoprotein osteopontin, a potent inhibitor of mineralization normally degraded by PHEX, accumulates within the bone matrix. Conventional therapy consisting of supplementation with phosphate and vitamin D analogs is burdensome and the effects on bone material poorly characterized. We analyzed transiliac bone biopsies from four adult patients, two of them severely affected due to no diagnosis and no treatment until adulthood. We used light microscopy, qBEI and FTIRI to study histology, histomorphometry, bone mineralization density distribution, properties of the organic matrix and size of hypomineralized periosteocytic lesions. Non-treatment resulted in severe osteomalacia, twice the amount of mineralized trabecular volume, multiple osteon-like perforations, continuity of lamellae from mineralized to unmineralized areas and distinctive patches of woven bone. Periosteocytic lesions were larger than in treated patients. The latter had nearly normal osteoid thicknesses, although surface was still elevated. The median calcium content of the matrix was always within normal range, although the percentage of lowly mineralized bone areas was highly increased in non-treated patients, resulting in a marked heterogeneity in mineralization. Divalent collagen cross-links were evident independently of the mineral content of the matrix. Broad osteoid seams lacked measurable pyridinoline, a mature trivalent cross-link and exhibited considerable acidic lipid content, typically found in matrix vesicles. Based on our results, we propose a model that possibly integrates the relationship between the observed mineralization disturbances, FGF23 secretion and the known osteopontin accumulation in XLH.
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Affiliation(s)
- Nadja Fratzl-Zelman
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria.
| | - Sonja Gamsjaeger
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Stéphane Blouin
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Roland Kocijan
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria; 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | | | - Stamatia Rokidi
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Kamilla Nawrot-Wawrzyniak
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Katharina Roetzer
- Center for Medical Genetics, Hanusch Hospital, Vienna, Austria; Medical School, Sigmund Freud Private University, Vienna, Austria
| | - Gökhan Uyanik
- Center for Medical Genetics, Hanusch Hospital, Vienna, Austria; Medical School, Sigmund Freud Private University, Vienna, Austria
| | - Gabriele Haeusler
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Austria
| | - Elizabeth Shane
- Division of Endocrinology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Adi Cohen
- Division of Endocrinology, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Klaus Klaushofer
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Eleftherios P Paschalis
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Paul Roschger
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria
| | - Peter Fratzl
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, Potsdam, Germany
| | - Jochen Zwerina
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria; 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | - Elisabeth Zwettler
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Centre Meidling, 1st Medical Department Hanusch Hospital, Vienna, Austria; Medical Directorate, Hanusch Hospital, Vienna, Austria
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17
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Kubota T, Fukumoto S, Cheong HI, Michigami T, Namba N, Ito N, Tokunaga S, Gibbs Y, Ozono K. Long-term outcomes for Asian patients with X-linked hypophosphataemia: rationale and design of the SUNFLOWER longitudinal, observational cohort study. BMJ Open 2020; 10:e036367. [PMID: 32601114 PMCID: PMC7328740 DOI: 10.1136/bmjopen-2019-036367] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION X-linked hypophosphataemic rickets/osteomalacia (XLH) is a chronic, debilitating genetic disease characterised by skeletal abnormalities and growth disorder. The burden of XLH begins in childhood and continues throughout life. Conventional medical therapy with phosphate, active vitamin D and surgery do not address the underlying pathophysiology of the disease. While treatment during childhood may improve bone deformity and growth retardation, a large proportion of adult patients still fail to reach normal stature. Furthermore, adult patients with XLH report comorbidities associated with unresolved childhood disease, as well as newly developed disease-related complications and significantly impaired quality of life (QOL). Despite the multiple negative aspects of XLH, Asian consensus statements for diagnosis and management are lacking. METHODS AND ANALYSIS The Study of longitUdinal observatioN For patients with X-Linked hypOphosphataemic rickets/osteomalacia in collaboration With Asian partnERs study is a longitudinal observational cohort study of patients with XLH, designed to determine the medical characteristics and burdens (physical, emotional and financial) of this progressive disease and to evaluate the impact of treatment (including the use of burosumab) on clinical outcomes. The study was initiated in April 2018, and registration will remain open until 30 April 2022. The sample size planned for analyses is 160 patients, consisting of 100 patients in Japan and 60 patients in Korea. Up to 5 years of observation are planned per patient, from enrolment through to April 2023. Prospective and retrospective data will be collected to evaluate variables, including height/growth, rickets severity score, QOL, motor function and biomarkers for phosphate metabolism and bone turnover. ETHICS AND DISSEMINATION Ethics approval was obtained from the Ethics Committee of Osaka University, the Ethics Committee of Kyowa Kirin Co and by the Ethics Committee of each participating medical institution. Two interim analyses and associated publications are planned using retrospective and enrolment data at year 1 and results at year 3. TRIAL REGISTRATION NUMBERS NCT03745521; UMIN000031605.
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Affiliation(s)
- Takuo Kubota
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Seiji Fukumoto
- Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Hae Il Cheong
- Department of Pediatric Nephrology, Seoul National University Children's Hospital, Seoul, Republic of Korea
| | - Toshimi Michigami
- Department of Bone and Mineral Research, Osaka Women's and Children's Hospital, Izumi, Japan
| | - Noriyuki Namba
- Department of Pediatrics and Perinatology, Faculty of Medicine, Tottori University, Tottori, Japan
| | - Nobuaki Ito
- Division of Nephrology and Endocrinology, The University of Tokyo Hospital, Tokyo, Japan
| | - Shin Tokunaga
- Medical Affairs Department, Kyowa Kirin Co Ltd, Tokyo, Japan
| | - Yoshimi Gibbs
- Medical Affairs Department, Kyowa Kirin Co Ltd, Tokyo, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Suita, Japan
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18
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Raimann A, Mindler GT, Kocijan R, Bekes K, Zwerina J, Haeusler G, Ganger R. Multidisciplinary patient care in X-linked hypophosphatemic rickets: one challenge, many perspectives. Wien Med Wochenschr 2020; 170:116-123. [PMID: 31993875 PMCID: PMC7098922 DOI: 10.1007/s10354-019-00732-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 12/17/2019] [Indexed: 11/29/2022]
Abstract
X‑linked hypophosphatemic rickets (XLH, OMIM #307800) is a rare genetic metabolic disorder caused by dysregulation of fibroblast-like growth factor 23 (FGF23) leading to profound reduction in renal phosphate reabsorption. Impaired growth, severe rickets and complex skeletal deformities are direct consequences of hypophosphatemia representing major symptoms of XLH during childhood. In adults, secondary complications including early development of osteoarthritis substantially impair quality of life and cause significant clinical burden. With the global approval of the monoclonal FGF23 antibody burosumab, a targeted treatment with promising results in phase III studies is available for children with XLH. Nevertheless, complete phenotypic rescue is rarely achieved and remaining multisystemic symptoms demand multidisciplinary specialist care. Coordination of patient management within the major medical disciplines is a mainstay to optimize treatment and reduce disease burden. This review aims to depict different perspectives in XLH patient care in the setting of a multidisciplinary centre of expertise for rare bone diseases.
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Affiliation(s)
- Adalbert Raimann
- Comprehensive Center for Pediatrics, Department of Pediatrics and Adolescent Medicine, Division of Pediatric Pulmonology, Allergology and Endocrinology, Medical University of Vienna, Vienna, Austria. .,Vienna Bone and Growth Centre, Vienna, Austria.
| | - Gabriel T Mindler
- Department of Pediatric Orthopaedics, Orthopaedic Hospital Speising, Vienna, Austria.,Vienna Bone and Growth Centre, Vienna, Austria
| | - Roland Kocijan
- Hanusch Hospital of the WGKK and AUVA Trauma Center, 1st Medical Department at Hanusch Hospital, Ludwig Boltzmann Institute of Osteology, Vienna, Austria.,Vienna Bone and Growth Centre, Vienna, Austria
| | - Katrin Bekes
- Department of Pediatric Dentistry, School of Dentistry, Medical University of Vienna, Vienna, Austria
| | - Jochen Zwerina
- Hanusch Hospital of the WGKK and AUVA Trauma Center, 1st Medical Department at Hanusch Hospital, Ludwig Boltzmann Institute of Osteology, Vienna, Austria.,Vienna Bone and Growth Centre, Vienna, Austria
| | - Gabriele Haeusler
- Comprehensive Center for Pediatrics, Department of Pediatrics and Adolescent Medicine, Division of Pediatric Pulmonology, Allergology and Endocrinology, Medical University of Vienna, Vienna, Austria.,Vienna Bone and Growth Centre, Vienna, Austria
| | - Rudolf Ganger
- Department of Pediatric Orthopaedics, Orthopaedic Hospital Speising, Vienna, Austria.,Vienna Bone and Growth Centre, Vienna, Austria
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19
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Novais A, Lesieur J, Sadoine J, Slimani L, Baroukh B, Saubaméa B, Schmitt A, Vital S, Poliard A, Hélary C, Rochefort GY, Chaussain C, Gorin C. Priming Dental Pulp Stem Cells from Human Exfoliated Deciduous Teeth with Fibroblast Growth Factor-2 Enhances Mineralization Within Tissue-Engineered Constructs Implanted in Craniofacial Bone Defects. Stem Cells Transl Med 2019; 8:844-857. [PMID: 31016898 PMCID: PMC6646701 DOI: 10.1002/sctm.18-0182] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 12/03/2018] [Indexed: 12/17/2022] Open
Abstract
The craniofacial area is prone to trauma or pathologies often resulting in large bone damages. One potential treatment option is the grafting of a tissue-engineered construct seeded with adult mesenchymal stem cells (MSCs). The dental pulp appears as a relevant source of MSCs, as dental pulp stem cells display strong osteogenic properties and are efficient at bone formation and repair. Fibroblast growth factor-2 (FGF-2) and/or hypoxia primings were shown to boost the angiogenesis potential of dental pulp stem cells from human exfoliated deciduous teeth (SHED). Based on these findings, we hypothesized here that these primings would also improve bone formation in the context of craniofacial bone repair. We found that both hypoxic and FGF-2 primings enhanced SHED proliferation and osteogenic differentiation into plastically compressed collagen hydrogels, with a much stronger effect observed with the FGF-2 priming. After implantation in immunodeficient mice, the tissue-engineered constructs seeded with FGF-2 primed SHED mediated faster intramembranous bone formation into critical size calvarial defects than the other groups (no priming and hypoxia priming). The results of this study highlight the interest of FGF-2 priming in tissue engineering for craniofacial bone repair. Stem Cells Translational Medicine 2019;8:844&857.
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Affiliation(s)
- Anita Novais
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
- AP‐HP Département d'OdontologieHôpitaux Universitaires PNVS, Charles Foix et Henri MondorIle de FranceFrance
| | - Julie Lesieur
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
| | - Jérémy Sadoine
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
| | - Lotfi Slimani
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
| | - Brigitte Baroukh
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
| | - Bruno Saubaméa
- Cellular and Molecular Imaging FacilityInserm US25, CNRS UMS 3612, Faculté de Pharmacie de Paris, Université Paris Descartes Sorbonne Paris CitéParisFrance
| | - Alain Schmitt
- Cochin Institute, Transmission Electron Microscopy Platform, INSERM U1016, CNRS UMR8104Université Paris Descartes Sorbonne Paris CitéParisFrance
| | - Sibylle Vital
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
- AP‐HP Département d'OdontologieHôpitaux Universitaires PNVS, Charles Foix et Henri MondorIle de FranceFrance
| | - Anne Poliard
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
| | - Christophe Hélary
- Laboratoire de Chimie de la Matière Condensée de ParisSorbonne Universités, CNRS, Collège de FranceParisFrance
| | - Gaël Y. Rochefort
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
| | - Catherine Chaussain
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
- AP‐HP Département d'OdontologieHôpitaux Universitaires PNVS, Charles Foix et Henri MondorIle de FranceFrance
| | - Caroline Gorin
- EA 2496 Pathologies, Imagerie et Biothérapies Orofaciales et Plateforme Imagerie du Vivant (PIV)Dental School, Université Paris Descartes Sorbonne Paris CitéMontrougeFrance
- AP‐HP Département d'OdontologieHôpitaux Universitaires PNVS, Charles Foix et Henri MondorIle de FranceFrance
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Gordon RJ, Levine MA. Burosumab treatment of children with X-linked hypophosphataemic rickets. Lancet 2019; 393:2364-2366. [PMID: 31104830 DOI: 10.1016/s0140-6736(19)31054-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 04/16/2019] [Indexed: 10/26/2022]
Affiliation(s)
- Rebecca J Gordon
- Division of Endocrinology and Diabetes and Center for Bone Health, Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Michael A Levine
- Division of Endocrinology and Diabetes and Center for Bone Health, Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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21
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Amenta E, King HE, Petermann H, Uskoković V, Tommasini SM, Macica CM. Vibrational spectroscopic analysis of hydroxyapatite in HYP mice and individuals with X-linked hypophosphatemia. Ther Adv Chronic Dis 2018; 9:268-281. [PMID: 30719271 PMCID: PMC6348532 DOI: 10.1177/2040622318804753] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 07/20/2018] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND X-linked hypophosphatemia (XLH) is the most common form of familial phosphate-wasting disorders, due to an inactivating mutation in the phosphate-regulating neutral endopeptidase, X-linked gene. Persistent osteomalacia, enthesophytes, osteophytes, degenerative arthritis and dental abscesses/periodontal disease dominate the adult disorder. However, the impact of insufficient phosphate on hydroxyapatite composition, the major inorganic component of bone and teeth, is unknown in individuals with XLH. METHODS Using Raman spectroscopy, the carbonate (CO3 2-) to phosphate (PO4 3-) ion ratio was measured in HYP and wild-type mice and in primary and permanent teeth from XLH individuals and unaffected controls. RESULTS There was a significant difference in carbonate ion substitution between the HYP and wild-type femoral cortical bone (0.36 ± 0.08 versus 0.24 ± 0.04; p < 0.001). Carbonate ion substitution levels were also higher in permanent XLH teeth compared with unaffected individuals (0.39 ± 0.12 versus 0.23 ± 0.04; p < 0.001), but not in primary teeth (0.29 ± 0.11 versus 0.26 ± 0.02; p = 0.29). Complementary Fourier transform infrared analyses demonstrated higher relative intensities of the four major vibrational bands originating from the carbonate anion in XLH teeth compared with unaffected controls. CONCLUSION Ionic substitution within the crystal lattice is a common feature of hydroxyapatite and one that confers the physiological properties of bone that impact mechanical strength and the process of bone remodeling. Our data demonstrating anionic substitution in human dentin from individuals with XLH validate the use of dentin as a proxy for bone and to better understand the molecular adaptations that occur in the biochemical milieu of XLH.
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Affiliation(s)
- Eva Amenta
- Department of Medical Sciences, Frank H. Netter, M.D., School of Medicine at Quinnipiac University, North Haven, CT, USA
| | - Helen E. King
- Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands
| | - Holger Petermann
- Department of Geology and Geophysics, Yale University, New Haven, CT, USA
| | - Vuk Uskoković
- Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, Irvine, CA, USA
| | - Steven M. Tommasini
- Department of Orthopaedics and Rehabilitation, Yale University, New Haven, CT, USA
| | - Carolyn M. Macica
- Frank H. Netter MD School of Medicine, Quinnipiac University, 275 Mt. Carmel Avenue, NH-MED MNH-311H, Hamden, CT 06518, USA
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Chesher D, Oddy M, Darbar U, Sayal P, Casey A, Ryan A, Sechi A, Simister C, Waters A, Wedatilake Y, Lachmann RH, Murphy E. Outcome of adult patients with X-linked hypophosphatemia caused by PHEX gene mutations. J Inherit Metab Dis 2018; 41:865-876. [PMID: 29460029 PMCID: PMC6133187 DOI: 10.1007/s10545-018-0147-6] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 01/07/2018] [Accepted: 01/24/2018] [Indexed: 01/09/2023]
Abstract
X-linked hypophosphatemia (XLH) is the most common monogenic disorder causing hypophosphatemia. This case-note review documents the clinical features and the complications of treatment in 59 adults (19 male, 40 female) with XLH. XLH is associated with a large number of private mutations; 37 different mutations in the PHEX gene were identified in this cohort, 14 of which have not been previously reported. Orthopaedic involvement requiring surgical intervention (osteotomy) was frequent. Joint replacement and decompressive laminectomy were observed in those older than 40 years. Dental disease (63%), nephrocalcinosis (42%), and hearing impairment (14%) were also common. The rarity of the disease and the large number of variants make it difficult to discern specific genotype-phenotype relationships. A new treatment, an anti-FGF23 antibody, that may affect the natural history of the disease is currently being investigated in clinical trials.
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Affiliation(s)
- Douglas Chesher
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
- New South Wales Health Pathology, Royal North Shore Hospital, St Leonards, NSW, Australia
| | - Michael Oddy
- Department of Trauma and Orthopaedics, University College London Hospitals NHS Foundation Trust, London, UK
| | - Ulpee Darbar
- Department of Periodontology, Eastman Dental Hospital, London, UK
| | - Parag Sayal
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
| | - Adrian Casey
- Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
| | - Aidan Ryan
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
- Chemical Pathology and Metabolic Medicine, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Annalisa Sechi
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
- Centre for Rare Disease, Academic Hospital of Udine, Udine, Italy
| | - Charlotte Simister
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
| | - Aoife Waters
- Institute of Child Health, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Yehani Wedatilake
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
- Imperial College London NHS Foundation Trust, London, UK
| | - Robin H Lachmann
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
| | - Elaine Murphy
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK.
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