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Astudillo-Ortiz E, Babo PS, Sunde PT, Galler KM, Gomez-Florit M, Gomes ME. Endodontic Tissue Regeneration: A Review for Tissue Engineers and Dentists. TISSUE ENGINEERING. PART B, REVIEWS 2023; 29:491-513. [PMID: 37051704 DOI: 10.1089/ten.teb.2022.0211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
The paradigm shift in the endodontic field from replacement toward regenerative therapies has witnessed the ever-growing research in tissue engineering and regenerative medicine targeting pulp-dentin complex in the past few years. Abundant literature on the subject that has been produced, however, is scattered over diverse areas of knowledge. Moreover, the terminology and concepts are not always consensual, reflecting the range of research fields addressing this subject, from endodontics to biology, genetics, and engineering, among others. This fact triggered some misinterpretations, mainly when the denominations of different approaches were used as synonyms. The evaluation of results is not precise, leading to biased conjectures. Therefore, this literature review aims to conceptualize the commonly used terminology, summarize the main research areas on pulp regeneration, identify future trends, and ultimately clarify whether we are really on the edge of a paradigm shift in contemporary endodontics toward pulp regeneration.
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Affiliation(s)
- Esteban Astudillo-Ortiz
- 3B's Research Group, I3Bs-Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
- Department of Endodontics, School of Dentistry, University of Cuenca, Cuenca, Ecuador
| | - Pedro S Babo
- 3B's Research Group, I3Bs-Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
| | - Pia T Sunde
- Department of Endodontics, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Kerstin M Galler
- Department of Operative Dentistry and Periodontology, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany
| | | | - Manuela E Gomes
- 3B's Research Group, I3Bs-Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, Braga, Portugal
- ICVS/3B's-PT Government Associate Laboratory, Braga, Portugal
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Yu Y, Rong K, Yao D, Zhang Q, Cao X, Rao B, Xia Y, Lu Y, Shen Y, Yao Y, Xu H, Ma P, Cao Y, Qin A. The structural pathology for hypophosphatasia caused by malfunctional tissue non-specific alkaline phosphatase. Nat Commun 2023; 14:4048. [PMID: 37422472 PMCID: PMC10329691 DOI: 10.1038/s41467-023-39833-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Accepted: 06/30/2023] [Indexed: 07/10/2023] Open
Abstract
Hypophosphatasia (HPP) is a metabolic bone disease that manifests as developmental abnormalities in bone and dental tissues. HPP patients exhibit hypo-mineralization and osteopenia due to the deficiency or malfunction of tissue non-specific alkaline phosphatase (TNAP), which catalyzes the hydrolysis of phosphate-containing molecules outside the cells, promoting the deposition of hydroxyapatite in the extracellular matrix. Despite the identification of hundreds of pathogenic TNAP mutations, the detailed molecular pathology of HPP remains unclear. Here, to address this issue, we determine the crystal structures of human TNAP at near-atomic resolution and map the major pathogenic mutations onto the structure. Our study reveals an unexpected octameric architecture for TNAP, which is generated by the tetramerization of dimeric TNAPs, potentially stabilizing the TNAPs in the extracellular environments. Moreover, we use cryo-electron microscopy to demonstrate that the TNAP agonist antibody (JTALP001) forms a stable complex with TNAP by binding to the octameric interface. The administration of JTALP001 enhances osteoblast mineralization and promoted recombinant TNAP-rescued mineralization in TNAP knockout osteoblasts. Our findings elucidate the structural pathology of HPP and highlight the therapeutic potential of the TNAP agonist antibody for osteoblast-associated bone disorders.
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Affiliation(s)
- Yating Yu
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China
| | - Kewei Rong
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Deqiang Yao
- State Key Laboratory of Oncogenes and Related Genes, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Qing Zhang
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China
| | - Xiankun Cao
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
| | - Bing Rao
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China
| | - Ying Xia
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China
| | - Yi Lu
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China
| | - Yafeng Shen
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China
| | - Ying Yao
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, 201210, China
| | - Hongtao Xu
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, 201210, China
| | - Peixiang Ma
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China.
| | - Yu Cao
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China.
- Institute of Precision Medicine, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, 115 Jinzun Road, Shanghai, 200125, China.
| | - An Qin
- Department of Orthopedics, Shanghai Key Laboratory of Orthopedics Implant, the Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, China.
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Different Dental Manifestations in Sisters with the Same ALPL Gene Mutation: A Report of Two Cases. CHILDREN (BASEL, SWITZERLAND) 2022; 9:children9121850. [PMID: 36553293 PMCID: PMC9777029 DOI: 10.3390/children9121850] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/24/2022] [Accepted: 11/25/2022] [Indexed: 11/29/2022]
Abstract
Hypophosphatasia (HPP) is an inherited disease caused by mutation of the alkaline phosphatase (ALPL) gene in an autosomal dominant or an autosomal recessive manner. The main symptoms of HPP are bone hypomineralization and early exfoliation of the primary teeth. Some of the mutations identified in autosomal dominant families are reported to have dominant negative effects. In addition, the penetrance can vary among patients with the same variant even within the same family, resulting in various phenotypes of systemic symptoms. However, differences in dental symptoms between patients with HPP and carriers with the same ALPL variant have not been reported. Herein, we report on two sisters who had the same heterozygous ALPL variant with dominant negative effects. The older sister had bone and dental symptoms and was diagnosed with childhood HPP. In contrast, the younger sister was a carrier with no bone and dental symptoms. It can be inferred that this phenomenon was caused by the difference in penetrance. This case revealed that carriers with the ALPL mutation may have no dental symptoms characteristic of HPP. Because HPP is sometimes progressive, it is very important to carefully monitor carriers to detect the possible onset of dental and systemic symptoms.
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Zhang Q, Qin Z, Yi S, Wei H, Zhou XZ, Shen F. Case Report: Variations in the ALPL Gene in Chinese Patients With Hypophosphatasia. Front Genet 2021; 12:732621. [PMID: 34712267 PMCID: PMC8546181 DOI: 10.3389/fgene.2021.732621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/27/2021] [Indexed: 01/27/2023] Open
Abstract
Background: Hypophosphatasia (HPP) is an autosomal genetic disorder characterized biochemically by abnormal of bone parameters and serum alkaline phosphatase (ALP) activity as well as clinically by deficiency of teeth and bone mineralization. The clinical presentation is a continuum ranging from a prenatal lethal form with no skeletal mineralization to a mild form with late adult onset presenting with non-pathognomonic symptoms. ALP deficiency is the key to the pathogenesis of abnormal metabolism and skeletal system damage in HPP patients. Methods: We investigated five patients with skeletal dysplasia in the clinic. Whole-exome sequencing was performed in order to aid diagnosis of the patients. Results: Eight variants in the ALPL gene in the five unrelated Chinese patients (PA-1: c.649_650insC and c.707A > G; PA2: c.98C > T and c.707A > G; PA3: c.407G > A and c.650delTinsCTAA; PA4: c.1247G > T (homozygous); PA5: c.406C > T and c.1178A > G; NM_000478.5) were found. These variations caused two types of HPP: perinatal HPP and Odonto HPP. All cases reported in this study were autosomal recessive. Among the variants, c.1247G > T/p.Gly416Val (PA-4); c.1178A > G/p.Asn393Ser (PA-5) and c.707A > G/p.Tyr236Cys (PA-1, PA-2) have never been reported before. Conclusion: Clinical phenotypes of perinatal HPP (PA-1,PA-2,PA-3 and PA-4) include skeletal dysplasia, shorter long bones, bowing of long bones, tetraphocomelia, abnormal posturing and abnormal bone ossification. Odonto HPP (PA-5) only presents as dental abnormality with severe dental caries and decreased ALP activity. Our study extends the pool of ALPL variants in different populations.
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Affiliation(s)
- Qiang Zhang
- The Maternal and Child Health Care Hospital of Guangxi Zhuang Autonomous Region, Guangxi Birth Defects Prevention and Control Institute, Nanning, China.,Laboratory of Genetic Metabolism Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Zailong Qin
- The Maternal and Child Health Care Hospital of Guangxi Zhuang Autonomous Region, Guangxi Birth Defects Prevention and Control Institute, Nanning, China.,Laboratory of Genetic Metabolism Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Shang Yi
- Laboratory of Genetic Metabolism Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Hao Wei
- Laboratory of Genetic Metabolism Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Xun Zhao Zhou
- Laboratory of Genetic Metabolism Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Fei Shen
- Laboratory of Genetic Metabolism Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
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Su N, Zhu M, Cheng X, Xu K, Kocijan R, Zhang H. Six ALPL gene variants in five children with hypophosphatasia. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:888. [PMID: 34164522 PMCID: PMC8184488 DOI: 10.21037/atm-21-2096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background Hypophosphatasia (HPP) is a rare hereditary disorder characterized by defective bone and tooth mineralization caused by mutations in the alkaline phosphatase (ALPL) gene encoding tissue-nonspecific alkaline phosphatase (TNSALP). Here we performed clinical and molecular studies on 5 HPP children to investigate the pathogenic mechanisms of the ALPL gene variants. Methods Clinical and genetic analyses were performed on 5 HPP children, and the loci where ALPL variants were identified. Plasmids containing the relevant loci were constructed. The molecular and cellular mechanisms of the pathogenic ALPL variants were investigated by cellular immunofluorescence, enzyme activity assay, and protein expression assay. Results A total of 6 ALPL variants were identified in 5 HPP children: proband 1: c.346G>A (p.A116T); proband 2: c.346G>A (p.A116T)/deletions from c.1097 to c.1099 CCT (p.T366_S367deli) compound heterozygous variant; proband 3: insertion of G from c.1014 to c.1015 (p.H338fs)/c.1446C>A (p.H482Q) compound heterozygous variant; proband 4: c.920C>T (p.P307L); and proband 5: c.883A>G (p.M295V). Twenty-four hours after the HEK-293T was transfected with different variant plasmids, its alkaline phosphatase activity and enzyme protein content were reduced compared with the wild type, and there were differences among different variants. Except for 1014-G-1015+C1446A, the degree of reduction in enzyme activity was negatively correlated with the severity of clinical manifestations. Immunofluorescence revealed that the variants (especially c.883A>G and c.920C>T) caused a decrease in alkaline phosphatase expression in the cellular membrane. Conclusions In total, 3 novel variants were identified in these 5 HPP children, the discovery of which will enrich the human ALPL gene mutation database. Different variants in the ALPL gene can downregulate the activity of TNSALP enzyme (and thus affect its function) by affecting protein expression and translational modifications. The same variant may cause clinical manifestations of different severities in different individuals due to the presence of dominant negative effects, alterations in noncoding sequences, blind area of intron regulatory region sequencing, and variations in environmental and individual factors. The molecular mechanisms via which the ALPL gene exerts its expression effect in vivo are highly variable and warrant further investigation.
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Affiliation(s)
- Na Su
- Department of Endocrinology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China.,Department of Child Endocrinology and Genetic Metabolism, Chengdu Women's and Children's Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Min Zhu
- Department of Endocrinology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
| | - Xinran Cheng
- Department of Child Endocrinology and Genetic Metabolism, Chengdu Women's and Children's Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Ke Xu
- Department of Child Endocrinology and Genetic Metabolism, Chengdu Women's and Children's Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Roland Kocijan
- Medical Faculty of Bone Diseases, Sigmund Freud University, Vienna, Austria.,Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA Trauma Center Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | - Huijiao Zhang
- Department of Endocrinology, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing, China
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Ohshima H, Amizuka N. Oral biosciences: The annual review 2019. J Oral Biosci 2020; 62:1-8. [PMID: 32109566 DOI: 10.1016/j.job.2020.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/10/2020] [Accepted: 02/10/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND Journal of Oral Biosciences is devoted to the advancement and dissemination of fundamental knowledge concerning every aspect of oral biosciences. HIGHLIGHT This review features review articles in the fields of "Bone Cell Biology," "Microbiology," "Oral Heath," "Biocompatible Materials," "Mouth Neoplasm," and "Biological Evolution" in addition to the review articles by winners of the Lion Dental Research Award ("Role of nicotinic acetylcholine receptors for modulation of microcircuits in the agranular insular cortex" and "Phospholipase C-related catalytically inactive protein: A novel signaling molecule for modulating fat metabolism and energy expenditure") and the Rising Members Award ("Pain mechanism of oral ulcerative mucositis and the therapeutic traditional herbal medicine hangeshashinto," "Mechanisms underlying the induction of regulatory T cells by sublingual immunotherapy," and "Regulation of osteoclast function via Rho-Pkn3-c-Src pathways"), presented by the Japanese Association for Oral Biology. CONCLUSION These reviews in the Journal of Oral Biosciences have inspired the readers of the journal to broaden their knowledge regarding various aspects of oral biosciences. The current editorial review introduces these exciting review articles.
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Affiliation(s)
- Hayato Ohshima
- Division of Anatomy and Cell Biology of the Hard Tissue, Department of Tissue Regeneration and Reconstruction, Niigata University Graduate School of Medical and Dental Science, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
| | - Norio Amizuka
- Department of Developmental Biology of Hard Tissue, Graduate School of Dental Medicine, Faculty of Dental Medicine, Hokkaido University, Kita 13 Nishi 7 Kita-ku, Sapporo 060-8586, Japan
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Molecular and cellular basis of hypophosphatasia. J Oral Biosci 2019; 61:141-148. [PMID: 31400546 DOI: 10.1016/j.job.2019.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/10/2019] [Accepted: 07/11/2019] [Indexed: 01/09/2023]
Abstract
BACKGROUND Hypophosphatasia (HPP) is an inherited disorder characterized by defective mineralization of the bone and teeth that is also associated with a deficiency of serum alkaline phosphatase (ALP). Patients with HPP exhibit a broad range of symptoms including stillbirth with an unmineralized skeleton, premature exfoliation and dental caries in childhood, and pseudo-fractures in adulthood. The broad clinical spectrum of HPP is attributed to various mutations in the ALPL gene, which encodes tissue-nonspecific alkaline phosphatase (TNSALP). Nevertheless, the molecular mechanisms underlying the genotypic and phenotypic relationship of HPP remain unclear. HIGHLIGHT The expression of HPP-related TNSALP mutants in mammalian cells allows us to determine for the effects of mutations on the properties of TNSALP, which could contribute to a better understanding of the relationship between structure and function of TNSALP. CONCLUSION Molecular characterization of TNSALP mutants helps establish the etiology and onset of HPP.
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Taillandier A, Domingues C, Dufour A, Debiais F, Guggenbuhl P, Roux C, Cormier C, Cortet B, Porquet-Bordes V, Coury F, Geneviève D, Chiesa J, Colin T, Fletcher E, Guichet A, Javier RM, Laroche M, Laurent M, Lausch E, LeHeup B, Lukas C, Schwabe G, van der Burgt I, Muti C, Simon-Bouy B, Mornet E. Genetic analysis of adults heterozygous for ALPL mutations. J Bone Miner Metab 2018; 36:723-733. [PMID: 29236161 DOI: 10.1007/s00774-017-0888-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/11/2017] [Indexed: 12/11/2022]
Abstract
Hypophosphatasia (HPP) is a rare inherited metabolic bone disease due to a deficiency of the tissue nonspecific alkaline phosphatase isoenzyme (TNSALP) encoded by the ALPL gene. Patients have consistently low serum alkaline phosphatase (AP), so that this parameter is a good hallmark of the disease. Adult HPP is heterogeneous, and some patients present only mild nonpathognomonic symptoms which are also common in the general population such as joint pain, osteomalacia and osteopenia, chondrocalcinosis, arthropathy and musculoskeletal pain. Adult HPP may be recessively or dominantly inherited; the latter case is assumed to be due to the dominant negative effect (DNE) of missense mutations derived from the functional homodimeric structure of TNSALP. However, there is no biological argument excluding the possibility of other causes of dominant HPP. Rheumatologists and endocrinologists are increasingly solicited for patients with low AP and nonpathognomonic symptoms of HPP. Many of these patients are heterozygous for an ALPL mutation and a challenging question is to determine if these symptoms, which are also common in the general population, are attributable to their heterozygous ALPL mutation or not. In an attempt to address this question, we reviewed a cohort of 61 adult patients heterozygous for an ALPL mutation. Mutations were distinguished according to their statistical likelihood to show a DNE. One-half of the patients carried mutations predicted with no DNE and were slightly less severely affected by the age of onset, serum AP activity and history of fractures. We hypothesized that these mutations result in another mechanism of dominance or are recessive alleles. To identify other genetic factors that could trigger the disease phenotype in heterozygotes for potential recessive mutations, we examined the next-generation sequencing results of 32 of these patients for a panel of 12 genes involved in the differential diagnosis of HPP or candidate modifier genes of HPP. The heterozygous genotype G/C of the COL1A2 coding SNP rs42524 c.1645C > G (p.Pro549Ala) was associated with the severity of the phenotype in patients carrying mutations with a DNE whereas the homozygous genotype G/G was over-represented in patients carrying mutations without a DNE, suggesting a possible role of this variant in the disease phenotype. These preliminary results support COL1A2 as a modifier gene of HPP and suggest that a significant proportion of adult heterozygotes for ALPL mutations may have unspecific symptoms not attributable to their heterozygosity.
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Affiliation(s)
- Agnès Taillandier
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Christelle Domingues
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Annika Dufour
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Françoise Debiais
- Service de Rhumatologie, CHU de Poitiers, 86021, Poitiers cedex, France
| | - Pascal Guggenbuhl
- Service de Rhumatologie, hôpital Sud, CHU de Rennes, 16, boulevard de Bulgarie, BP90347, 35203, Rennes cedex 2, France
| | | | | | | | - Valérie Porquet-Bordes
- Endocrinologie, Maladies Osseuses, Génétique et Gynécologie Médicale, Hôpital des Enfants, CHU de Toulouse, Toulouse Cedex 9, France
| | - Fabienne Coury
- Service de Rhumatologie, CHU Lyon, Centre Hospitalier Lyon-Sud, Pierre Bénite, France
| | - David Geneviève
- Service de Génétique Clinique, Département de Génétique Médicale, maladies rares et médecine personnalisée, CHU Montpellier, université Montpellier, unité Inserm U1183, Montpellier, France
| | - Jean Chiesa
- Department of Genetics, University Hospital, Nîmes, France
| | - Thierry Colin
- Service de Rhumatologie, CH Public du Cotentin, Cherbourg, France
| | - Elaine Fletcher
- Clinical Genetics, Molecular Medicine Center, Western General Hospital, Edinburgh, UK
| | - Agnès Guichet
- Département Biochimie et génétique, CHU d'Angers, Angers, France
| | | | - Michel Laroche
- Service de Rhumatologie, Hôpital Pierre-Paul Riquet, Toulouse, France
| | - Michael Laurent
- Center for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Ekkehart Lausch
- Universitätsklinikum Freiburg, Zentrum für Kinder- und Jugendmedizin, Freiburg, Germany
| | - Bruno LeHeup
- Médecine infantile 3, CHU Nancy, Vandoeuvre, France
| | - Cédric Lukas
- Département de Rhumatologie, CHRU Montpellier, Montpellier, France
| | - Georg Schwabe
- Otto-Heubner-Centrum für Kinder und Jugendmedizin Allgemeine Päediatrie Charité, Campus Virchow Klinikum Augustenburger Platz 1, Berlin, Germany
| | | | - Christine Muti
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Brigitte Simon-Bouy
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Etienne Mornet
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France.
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Abstract
Hypophosphatasia (HPP) is a rare inherited disorder primarily affecting bone and dental mineralization. Although there is a continuum in the severity of the disease, clinical forms may be arbitrarily distinguished on the basis of age at onset and the presence or absence of bone symptoms: perinatal, infantile, juvenile, adult, prenatal benign, and odontological. Severe forms (perinatal and infantile) are autosomally recessively inherited while less severe forms may be autosomally recessively or dominantly inherited. Genetic counseling is complicated by the coexistence of the two modes of inheritance, the incomplete penetrance of the dominant forms, the markedly variable expression of the disease, including intra-familial expression, and the existence of a benign prenatal form that may sometimes be difficult to distinguish from the severe prenatal form. The disease is due to loss-of-function mutations in the Alkaline Phosphatase-Liver (ALPL) gene encoding the tissue nonspecific alkaline phosphatase (TNSALP). The great variety of missence mutations and the dominant negative effect of some mutations largely explain the clinical heterogeneity. Directed mutagenesis studies allowed further elucidation of the cellular pathophysiology of HPP, classification of the alleles in terms of their severity and dominant negative effect, and molecular explanations of the dominant inheritance mode. Genetics significantly contributed to show that there are in fact two HPPs, rare, severe and recessive HPP, and mild recessive or mild dominant HPP, which is markedly more frequent and probably under-diagnosed. The prevalence of the severe forms of HPP has been estimated to be 1/300,000 in France and Northern Europe while the prevalence of the moderate forms of HPP may reach 1/6,370.
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Affiliation(s)
- E Mornet
- Service de biologie, unité de génétique constitutionnelle, centre hospitalier de Versailles, Le Chesnay, France.
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10
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Abstract
We review here clinical, pathophysiological, diagnostic, genetic and molecular aspects of Hypophosphatasia (HPP), a rare inherited metabolic disorder. The clinical presentation is a continuum ranging from a prenatal lethal form with no skeletal mineralization to a mild form with late adult onset presenting with nonpathognomonic symptoms. The prevalence of severe forms is low, whereas less severe forms are more frequently observed. The disease is caused by loss-of-function mutations in the ALPL gene encoding the Tissue Nonspecific Alkaline Phosphatase (TNSALP), a central regulator of mineralization. Severe forms are recessively inherited, whereas moderate forms are either recessively or dominantly inherited, and the more severe the disease is, the more often it is subject to recessive inheritance. The diagnosis is based on a constantly low alkaline phosphatase (AP) activity in serum and genetic testing that identifies ALPL mutations. More than 340 mutations have been identified and are responsible for the extraordinary clinical heterogeneity. A clear but imperfect genotype-phenotype correlation has been observed, suggesting that other genetic or environmental factors modulate the phenotype. Enzyme replacement therapy is now available for HPP, and other approaches, such as gene therapy, are currently being investigated.
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Affiliation(s)
- Etienne Mornet
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150 Le Chesnay, France.
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11
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Remde H, Cooper MS, Quinkler M. Successful Asfotase Alfa Treatment in an Adult Dialysis Patient With Childhood-Onset Hypophosphatasia. J Endocr Soc 2017; 1:1188-1193. [PMID: 29264574 PMCID: PMC5686618 DOI: 10.1210/js.2017-00307] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 08/15/2017] [Indexed: 11/19/2022] Open
Abstract
Hypophosphatasia is an inherited disease characterized by reduced alkaline phosphatase activity, extracellular accumulation of inorganic pyrophosphate, and impaired bone mineralization. Asfotase alfa (AA) is a recombinant human alkaline phosphatase therapy approved for treatment of pediatric-onset hypophosphatasia. Studies show promising outcome in AA-treated children with hypophosphatasia; however, data on adults with pediatric-onset hypophosphatasia are scarce. We report on a 59-year-old woman with childhood-onset hypophosphatasia and a history of multiple fractures and orthopedic procedures. Owing to renal failure (histological diagnosis: focal segmental glomerulosclerosis), hemodialysis was started in 2013. By the end of 2015, the patient was unable to walk, could only stand for 30 seconds, and was completely dependent on help for activities of daily living. After 13 months of AA therapy, the patient showed a dramatic increase in quality of life (increased mobility), reduction in pain medication, and a significant improvement in bone mineralization throughout the skeleton, including consolidation of existing fractures and no occurrence of new fractures. This case report demonstrates a relevant therapeutic success of AA treatment in an adult hemodialysis patient with childhood onset of hypophosphatasia.
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Affiliation(s)
- Hanna Remde
- Charité-University Medicine Berlin, 10117 Berlin Germany.,Endocrinology in Charlottenburg, 10627 Berlin, Germany
| | - Mark S Cooper
- Adrenal Steroid Group, ANZAC Research Institute, Concord Repatriation General Hospital, Concord, New South Wales 2139, Australia
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Molecular defect of tissue-nonspecific alkaline phosphatase bearing a substitution at position 426 associated with hypophosphatasia. Mol Cell Biochem 2016; 427:169-176. [DOI: 10.1007/s11010-016-2908-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 12/03/2016] [Indexed: 10/20/2022]
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13
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Komaru K, Satou Y, Al-Shawafi HA, Numa-Kinjoh N, Sohda M, Oda K. Glycosylation-deficient mutations in tissue-nonspecific alkaline phosphatase impair its structure and function and are linked to infantile hypophosphatasia. FEBS J 2016; 283:1168-79. [DOI: 10.1111/febs.13663] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 12/28/2015] [Accepted: 01/15/2016] [Indexed: 12/19/2022]
Affiliation(s)
- Keiichi Komaru
- Kitasato Junior College of Health and Hygienic Sciences; Japan
| | - Yasuhito Satou
- Division of Oral Biochemistry; Niigata University Graduate School of Medical and Dental Sciences; Japan
| | - Hiba A. Al-Shawafi
- Division of Oral Biochemistry; Niigata University Graduate School of Medical and Dental Sciences; Japan
| | - Natsuko Numa-Kinjoh
- Division of Oral Biochemistry; Niigata University Graduate School of Medical and Dental Sciences; Japan
| | - Miwa Sohda
- Division of Oral Biochemistry; Niigata University Graduate School of Medical and Dental Sciences; Japan
| | - Kimimitsu Oda
- Division of Oral Biochemistry; Niigata University Graduate School of Medical and Dental Sciences; Japan
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14
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Abstract
Hypophosphatasia (HPP) is due to deficient activity of the tissue-nonspecific isoenzyme of alkaline phosphatase (TNAP). This enzyme cleaves extracellular substrates inorganic pyrophosphates (PPi), pyridoxal-5'-phosphate (PLP), phosphoethanolamine (PEA) and nucleotides, and probably other substrates not yet identified. During the last 15 years the role of TNAP in mineralization, and to a less degree in brain, has been investigated, providing hypotheses and explanations for both bone and neuronal HPP phenotypes. ALPL, the gene encoding TNAP, is subject to many mutations, mostly missense mutations. A few number of mutations are recurrently found and may be quite frequent in particular populations. This reflects founder effects. The great variety of mutations results in a great number of compound heterozygous genotypes and in highly variable clinical expressivity. A good correlation was observed between the severity of the disease and in vitro enzymatic activity of the mutant protein measured after site-directed mutagenesis. Many missense mutations found in severe hypophosphatasia produced a mutant protein that failed to reach the cell membrane , was accumulated in the cis-Golgi and was subsequently degraded in the proteasome. Missense mutations located in the catalytic site or in the homodimer interface were often shown by site-directed mutagenesis to have a dominant negative effect. Currently molecular diagnosis of HPP is based on the sequencing of the coding sequence of ALPL that allows detection of approximately 95 % of mutations in severe cases. In addition, other genes, especially genes encoding proteins involved in the regulation of extracellular PPi concentration, could modify the phenotype (modifier genes).
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15
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Numa-Kinjoh N, Komaru K, Ishida Y, Sohda M, Oda K. Molecular phenotype of tissue-nonspecific alkaline phosphatase with a proline (108) to leucine substitution associated with dominant odontohypophosphatasia. Mol Genet Metab 2015; 115:180-5. [PMID: 25982064 DOI: 10.1016/j.ymgme.2015.05.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 05/11/2015] [Accepted: 05/11/2015] [Indexed: 11/25/2022]
Abstract
Hypophosphatasia (HPP) is a genetic disease characterized by defective calcification of hard tissues such as bone and teeth accompanying deficiency of serum alkaline phosphatase (ALP) activity. Its development results from various mutations in the ALPL gene encoding tissue-nonspecific ALP (TNSALP). HPP is known to be transmitted in an autosomal recessive or autosomal dominant manner. A point mutation (c.323C>T) in the ALPL gene leading to a proline to leucine substitution at position 108 of TNSALP was first reported in a patient diagnosed with odonto-HPP (M Herasse et al., J Med Genet 2003;40:605-609), although the effects of this mutation on the TNSALP molecule have not been elucidated. To understand the molecular basis of this dominantly transmitted HPP, we first characterized TNSALP (P108L) by expressing it in COS-1 cells transiently. In contrast to wild-type TNSALP (WT), TNSALP (P108L) showed virtually no ALP activity. When coexpressed with TNSALP (WT), TNSALP (P108L) significantly inhibited the enzyme activity of TNSALP (WT), confirming that this mutant TNSALP exerts a dominant negative effect on TNSALP (WT). Using immunofluorescence and digestion with phosphatidylinositol-specific phospholipase C, we demonstrated that TNSALP (P108L) was anchored to the cell surface via glycosylphosphatidylinositol-like TNSALP (WT) in a Tet-On CHO cell expression system. Consistent with this, TNSALP (P108L) acquired endo-β-N-acetylglucosaminidase H resistance and sialic acids, as evidenced by glycosidase treatments. Importantly, TNSALP (WT) largely formed a functional dimeric structure, while TNSALP (P108L) was found to be present as a monomer in the cell. This indicates that the molecular structure of TNSALP is affected by a missense mutation at position 108, which is in contact with the active site, such that it no longer assembles into the functional dimeric form. Collectively, these results may explain why TNSALP (P108L) loses its ALP activity, even though it is able to gain access to the cell surface.
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Affiliation(s)
- Natsuko Numa-Kinjoh
- Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Keiichi Komaru
- Kitasato Junior College of Health and Hygienic Sciences, Minami-Uonuma, Japan
| | - Yoko Ishida
- Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Miwa Sohda
- Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Kimimitsu Oda
- Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
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Sharma U, Pal D, Prasad R. Alkaline phosphatase: an overview. Indian J Clin Biochem 2014; 29:269-78. [PMID: 24966474 PMCID: PMC4062654 DOI: 10.1007/s12291-013-0408-y] [Citation(s) in RCA: 479] [Impact Index Per Article: 47.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 11/11/2013] [Indexed: 02/06/2023]
Abstract
Alkaline phosphatase (ALP; E.C.3.I.3.1.) is an ubiquitous membrane-bound glycoprotein that catalyzes the hydrolysis of phosphate monoesters at basic pH values. Alkaline phosphatase is divided into four isozymes depending upon the site of tissue expression that are Intestinal ALP, Placental ALP, Germ cell ALP and tissue nonspecific alkaline phosphatase or liver/bone/kidney (L/B/K) ALP. The intestinal and placental ALP loci are located near the end of long arm of chromosome 2 and L/B/K ALP is located near the end of the short arm of chromosome 1. Although ALPs are present in many mammalian tissues and have been studied for the last several years still little is known about them. The bone isoenzyme may be involved in mammalian bone calcification and the intestinal isoenzyme is thought to play a role in the transport of phosphate into epithelial cells of the intestine. In this review, we tried to provide an overview about the various forms, structure and functions of alkaline phosphatase with special focus on liver/bone/kidney alkaline phosphatase.
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Affiliation(s)
- Ujjawal Sharma
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Deeksha Pal
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Rajendra Prasad
- Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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