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Infante A, Alcorta-Sevillano N, Macías I, Cabodevilla L, Medhat D, Lafaver B, Crawford TK, Phillips CL, Bueno AM, Sagastizabal B, Arroyo M, Campino A, Gerovska D, Araúzo-Bravo M, Gener B, Rodríguez CI. Galunisertib downregulates mutant type I collagen expression and promotes MSCs osteogenesis in pediatric osteogenesis imperfecta. Biomed Pharmacother 2024; 175:116725. [PMID: 38744219 DOI: 10.1016/j.biopha.2024.116725] [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: 03/13/2024] [Revised: 05/03/2024] [Accepted: 05/06/2024] [Indexed: 05/16/2024] Open
Abstract
Qualitative alterations in type I collagen due to pathogenic variants in the COL1A1 or COL1A2 genes, result in moderate and severe Osteogenesis Imperfecta (OI), a rare disease characterized by bone fragility. The TGF-β signaling pathway is overactive in OI patients and certain OI mouse models, and inhibition of TGF-β through anti-TGF-β monoclonal antibody therapy in phase I clinical trials in OI adults is rendering encouraging results. However, the impact of TGF-β inhibition on osteogenic differentiation of mesenchymal stem cells from OI patients (OI-MSCs) is unknown. The following study demonstrates that pediatric skeletal OI-MSCs have imbalanced osteogenesis favoring the osteogenic commitment. Galunisertib, a small molecule inhibitor (SMI) that targets the TGF-β receptor I (TβRI), favored the final osteogenic maturation of OI-MSCs. Mechanistically, galunisertib downregulated type I collagen expression in OI-MSCs, with greater impact on mutant type I collagen, and concomitantly, modulated the expression of unfolded protein response (UPR) and autophagy markers. In vivo, galunisertib improved trabecular bone parameters only in female oim/oim mice. These results further suggest that type I collagen is a tunable target within the bone ECM that deserves investigation and that the SMI, galunisertib, is a promising new candidate for the anti-TGF-β targeting for the treatment of OI.
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Affiliation(s)
- Arantza Infante
- Stem Cells and Advanced Therapies Group, Biobizkaia Health Research Institute, Barakaldo, Spain
| | - Natividad Alcorta-Sevillano
- Stem Cells and Advanced Therapies Group, Biobizkaia Health Research Institute, Barakaldo, Spain; Department of Cell Biology and Histology, University of Basque Country UPV/EHU, Leioa, Spain
| | - Iratxe Macías
- Stem Cells and Advanced Therapies Group, Biobizkaia Health Research Institute, Barakaldo, Spain
| | - Leire Cabodevilla
- Stem Cells and Advanced Therapies Group, Biobizkaia Health Research Institute, Barakaldo, Spain
| | - Dalia Medhat
- Medical Biochemistry Department, National Research Centre, Dokki, Giza, Egypt
| | - Brittany Lafaver
- Department of Biochemistry, University of Missouri, Columbia, USA
| | - Tara K Crawford
- Department of Biochemistry, University of Missouri, Columbia, USA
| | | | - Ana M Bueno
- Department of Orthopedic Surgery, Getafe University Hospital, Madrid, Spain
| | | | - Maitane Arroyo
- Department of Traumatology, Basurto Hospital, Bilbao, Spain
| | - Ainara Campino
- Service of Pharmacy, Cruces University Hospital, Barakaldo, Spain
| | - Daniela Gerovska
- Computational Biology and Systems Biomedicine Research Group, Biogipuzkoa Health Research Institute, Donostia, Spain
| | - Marcos Araúzo-Bravo
- Computational Biology and Systems Biomedicine Research Group, Biogipuzkoa Health Research Institute, Donostia, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao 48009, Spain; Department of Cell Biology and Histology, Faculty of Medicine and Nursing, University of Basque Country (UPV/EHU), Spain
| | - Blanca Gener
- Stem Cells and Advanced Therapies Group, Biobizkaia Health Research Institute, Barakaldo, Spain; Service of Genetics, Cruces University Hospital, Barakaldo, Spain
| | - Clara I Rodríguez
- Stem Cells and Advanced Therapies Group, Biobizkaia Health Research Institute, Barakaldo, Spain.
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Zahn G, Baukmann HA, Wu J, Jordan J, Birkenfeld AL, Dirckx N, Schmidt MF. Targeting Longevity Gene SLC13A5: A Novel Approach to Prevent Age-Related Bone Fragility and Osteoporosis. Metabolites 2023; 13:1186. [PMID: 38132868 PMCID: PMC10744747 DOI: 10.3390/metabo13121186] [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: 11/09/2023] [Revised: 11/24/2023] [Accepted: 12/01/2023] [Indexed: 12/23/2023] Open
Abstract
Reduced expression of the plasma membrane citrate transporter SLC13A5, also known as INDY, has been linked to increased longevity and mitigated age-related cardiovascular and metabolic diseases. Citrate, a vital component of the tricarboxylic acid cycle, constitutes 1-5% of bone weight, binding to mineral apatite surfaces. Our previous research highlighted osteoblasts' specialized metabolic pathway facilitated by SLC13A5 regulating citrate uptake, production, and deposition within bones. Disrupting this pathway impairs bone mineralization in young mice. New Mendelian randomization analysis using UK Biobank data indicated that SNPs linked to reduced SLC13A5 function lowered osteoporosis risk. Comparative studies of young (10 weeks) and middle-aged (52 weeks) osteocalcin-cre-driven osteoblast-specific Slc13a5 knockout mice (Slc13a5cKO) showed a sexual dimorphism: while middle-aged females exhibited improved elasticity, middle-aged males demonstrated enhanced bone strength due to reduced SLC13A5 function. These findings suggest reduced SLC13A5 function could attenuate age-related bone fragility, advocating for SLC13A5 inhibition as a potential osteoporosis treatment.
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Affiliation(s)
- Grit Zahn
- Eternygen GmbH, Westhafenstrasse 1, 13353 Berlin, Germany
| | | | - Jasmine Wu
- Department of Orthopaedics, School of Medicine, University of Maryland-Baltimore, Baltimore, MD 21201, USA
| | - Jens Jordan
- German Aerospace Center (DLR), Institute of Aerospace Medicine, 51147 Cologne, Germany;
| | - Andreas L. Birkenfeld
- Department of Diabetology Endocrinology and Nephrology, Internal Medicine IV, University Hospital Tübingen, Eberhard Karls University Tübingen, 72074 Tübingen, Germany
- German Center for Diabetes Research (DZD), Institute of Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich, Eberhard Karls University Tübingen, 72074 Tübingen, Germany
- Department of Diabetes, Life Sciences and Medicine, Cardiovascular Medicine and Sciences, Kings College London, London WC2R 2LS, UK
| | - Naomi Dirckx
- Department of Orthopaedics, School of Medicine, University of Maryland-Baltimore, Baltimore, MD 21201, USA
| | - Marco F. Schmidt
- biotx.ai GmbH, Am Mühlenberg 11, 14476 Potsdam, Germany (M.F.S.)
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Kaya S, Alliston T, Evans DS. Genetic and Gene Expression Resources for Osteoporosis and Bone Biology Research. Curr Osteoporos Rep 2023; 21:637-649. [PMID: 37831357 PMCID: PMC11098148 DOI: 10.1007/s11914-023-00821-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/11/2023] [Indexed: 10/14/2023]
Abstract
PURPOSE OF REVIEW The integration of data from multiple genomic assays from humans and non-human model organisms is an effective approach to identify genes involved in skeletal fragility and fracture risk due to osteoporosis and other conditions. This review summarizes genome-wide genetic variation and gene expression data resources relevant to the discovery of genes contributing to skeletal fragility and fracture risk. RECENT FINDINGS Genome-wide association studies (GWAS) of osteoporosis-related traits are summarized, in addition to gene expression in bone tissues in humans and non-human organisms, with a focus on rodent models related to skeletal fragility and fracture risk. Gene discovery approaches using these genomic data resources are described. We also describe the Musculoskeletal Knowledge Portal (MSKKP) that integrates much of the available genomic data relevant to fracture risk. The available genomic resources provide a wealth of knowledge and can be analyzed to identify genes related to fracture risk. Genomic resources that would fill particular scientific gaps are discussed.
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Affiliation(s)
- Serra Kaya
- Department of Orthopedic Surgery, University of California, San Francisco, CA, USA
| | - Tamara Alliston
- Department of Orthopedic Surgery, University of California, San Francisco, CA, USA
| | - Daniel S Evans
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA.
- California Pacific Medical Center Research Institute, San Francisco, CA, USA.
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Marulanda J, Tauer JT, Boraschi-Diaz I, Bardai G, Rauch F. Effect of sclerostin inactivation in a mouse model of severe dominant osteogenesis imperfecta. Sci Rep 2023; 13:5010. [PMID: 36973504 PMCID: PMC10043013 DOI: 10.1038/s41598-023-32221-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 03/24/2023] [Indexed: 03/29/2023] Open
Abstract
Osteogenesis imperfecta (OI) is a rare bone disease that is associated with fractures and low bone mass. Sclerostin inhibition is being evaluated as a potential approach to increase bone mass in OI. We had previously found that in Col1a1Jrt/+ mice, a model of severe OI, treatment with an anti-sclerostin antibody had a minor effect on the skeletal phenotype. In the present study, we assessed the effect of genetic sclerostin inactivation in the Col1a1Jrt/+ mouse. We crossed Col1a1Jrt/+ mice with Sost knockout mice to generate Sost-deficient Col1a1Jrt/+ mice and assessed differences between Col1a1Jrt/+ mice with homozygous Sost deficiency and Col1a1Jrt/+ mice with heterozygous Sost deficiency. We found that Col1a1Jrt/+ mice with homozygous Sost deficiency had higher body mass, femur length, trabecular bone volume, cortical thickness and periosteal diameter as well as increased biomechanical parameters of bone strength. Differences between genotypes were larger at the age of 14 weeks than at 8 weeks of age. Transcriptome analysis of RNA extracted from the tibial diaphysis revealed only 5 differentially regulated genes. Thus, genetic inactivation of Sost increased bone mass and strength in the Col1a1Jrt/+ mouse. It appears from these observations that the degree of Sost suppression that is required for eliciting a beneficial response can vary with the genetic cause of OI.
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Affiliation(s)
- Juliana Marulanda
- Shriners Hospital for Children, 1003 Decarie, Montreal, QC, H4A 0A9, Canada
- Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - Josephine T Tauer
- Shriners Hospital for Children, 1003 Decarie, Montreal, QC, H4A 0A9, Canada
| | | | - Ghalib Bardai
- Shriners Hospital for Children, 1003 Decarie, Montreal, QC, H4A 0A9, Canada
| | - Frank Rauch
- Shriners Hospital for Children, 1003 Decarie, Montreal, QC, H4A 0A9, Canada.
- Department of Pediatrics, McGill University, Montreal, QC, Canada.
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Claeys L, Zhytnik L, Wisse LE, van Essen HW, Eekhoff EMW, Pals G, Bravenboer N, Micha D. Exploration of the skeletal phenotype of the Col1a1 +/Mov13 mouse model for haploinsufficient osteogenesis imperfecta type 1. Front Endocrinol (Lausanne) 2023; 14:1145125. [PMID: 36967771 PMCID: PMC10031054 DOI: 10.3389/fendo.2023.1145125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 02/17/2023] [Indexed: 03/29/2023] Open
Abstract
INTRODUCTION Osteogenesis Imperfecta is a rare genetic connective tissue disorder, characterized by skeletal dysplasia and fragile bones. Currently only two mouse models have been reported for haploinsufficient (HI) mild Osteogenesis Imperfecta (OI); the Col1a1 +/Mov13 (Mov13) and the Col1a1 +/-365 mouse model. The Mov13 mice were created by random insertion of the Mouse Moloney leukemia virus in the first intron of the Col1a1 gene, preventing the initiation of transcription. Since the development of the Mov13 mice almost four decades ago and its basic phenotypic characterization in the 90s, there have not been many further studies. We aimed to extensively characterize the Mov13 mouse model in order to critically evaluate its possible use for preclinical studies of HI OI. METHODS Bone tissue from ten heterozygous Mov13 and ten wild-type littermates (WT) C57BL/6J mice (50% males per group) was analyzed at eight weeks of age with bone histomorphometry, micro computed tomography (microCT), 3-point bending, gene expression of different collagens, as well as serum markers of bone turnover. RESULTS The Mov13 mouse presented a lower bone strength and impaired material properties based on our results of 3-point bending and microCT analysis respectively. In contrast, no significant differences were found for all histomorphometric parameters. In addition, no significant differences in Col1a1 bone expression were present, but there was a significant lower P1NP concentration, a bone formation marker, measured in serum. Furthermore, bone tissue of Mov13 mice presented significantly higher expression of collagens (Col1a2, Col5a1 and Col5a2), and bone metabolism markers (Bglap, Fgf23, Smad7, Edn1 and Eln) compared to WT. Finally, we measured a significantly lower Col1a1 expression in heart and skin tissue and also determined a higher expression of other collagens in the heart tissue. CONCLUSION Although we did not detect a significant reduction in Col1a1 expression in the bone tissue, a change in bone structure and reduction in bone strength was noted. Regrettably, the variability of the bone phenotype and the appearance of severe lymphoma in adult Mov13 mice, does not favor their use for the testing of new long-term drug studies. As such, a new HI OI type 1 mouse model is urgently needed.
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Affiliation(s)
- Lauria Claeys
- Department of Human Genetics, Amsterdam Movement Sciences, Tissue Function & Regeneration and Musculoskeletal Health, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Lidiia Zhytnik
- Department of Human Genetics, Amsterdam Movement Sciences, Tissue Function & Regeneration and Musculoskeletal Health, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Department of Traumatology and Orthopeadics, Institute of Clinical Medicine, The University of Tartu, Tartu, Estonia
| | - Lisanne E. Wisse
- Department of Human Genetics, Amsterdam Movement Sciences, Tissue Function & Regeneration and Musculoskeletal Health, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Huib W. van Essen
- Department of Clinical Chemistry, Amsterdam Movement Sciences, Tissue Function & Regeneration and Ageing & Vitality, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - E. Marelise W. Eekhoff
- Department of Endocrinology and Metabolism, Amsterdam Rare Bone Disease Center, Amsterdam University Medical Centers (UMC), Amsterdam, Netherlands
| | - Gerard Pals
- Department of Human Genetics, Amsterdam Movement Sciences, Tissue Function & Regeneration and Musculoskeletal Health, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Nathalie Bravenboer
- Department of Clinical Chemistry, Amsterdam Movement Sciences, Tissue Function & Regeneration and Ageing & Vitality, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Dimitra Micha
- Department of Human Genetics, Amsterdam Movement Sciences, Tissue Function & Regeneration and Musculoskeletal Health, Amsterdam University Medical Centers (UMC) location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- *Correspondence: Dimitra Micha,
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Alcorta-Sevillano N, Infante A, Macías I, Rodríguez CI. Murine Animal Models in Osteogenesis Imperfecta: The Quest for Improving the Quality of Life. Int J Mol Sci 2022; 24:ijms24010184. [PMID: 36613624 PMCID: PMC9820162 DOI: 10.3390/ijms24010184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/16/2022] [Accepted: 12/19/2022] [Indexed: 12/25/2022] Open
Abstract
Osteogenesis imperfecta is a rare genetic disorder characterized by bone fragility, due to alterations in the type I collagen molecule. It is a very heterogeneous disease, both genetically and phenotypically, with a high variability of clinical phenotypes, ranging from mild to severe forms, the most extreme cases being perinatal lethal. There is no curative treatment for OI, and so great efforts are being made in order to develop effective therapies. In these attempts, the in vivo preclinical studies are of paramount importance; therefore, serious analysis is required to choose the right murine OI model able to emulate as closely as possible the disease of the target OI population. In this review, we summarize the features of OI murine models that have been used for preclinical studies until today, together with recently developed new murine models. The bone parameters that are usually evaluated in order to determine the relevance of new developing therapies are exposed, and finally, current and innovative therapeutic strategies attempts considered in murine OI models, along with their mechanism of action, are reviewed. This review aims to summarize the in vivo studies developed in murine models available in the field of OI to date, in order to help the scientific community choose the most accurate OI murine model when developing new therapeutic strategies capable of improving the quality of life.
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Affiliation(s)
- Natividad Alcorta-Sevillano
- Stem Cells and Cell Therapy Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Plaza de Cruces S/N, 48903 Barakaldo, Spain
- Department of Cell Biology and Histology, University of Basque Country UPV/EHU, 48940 Leioa, Spain
| | - Arantza Infante
- Stem Cells and Cell Therapy Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Plaza de Cruces S/N, 48903 Barakaldo, Spain
| | - Iratxe Macías
- Stem Cells and Cell Therapy Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Plaza de Cruces S/N, 48903 Barakaldo, Spain
| | - Clara I. Rodríguez
- Stem Cells and Cell Therapy Laboratory, Biocruces Bizkaia Health Research Institute, Cruces University Hospital, Plaza de Cruces S/N, 48903 Barakaldo, Spain
- Correspondence:
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Mishra D, Kannan K, Meadows K, Macro J, Li M, Frankel S, Rogina B. INDY-From Flies to Worms, Mice, Rats, Non-Human Primates, and Humans. FRONTIERS IN AGING 2022; 2:782162. [PMID: 35822025 PMCID: PMC9261455 DOI: 10.3389/fragi.2021.782162] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/24/2021] [Indexed: 01/17/2023]
Abstract
I’m Not Dead Yet (Indy) is a fly homologue of the mammalian SLC13A5 (mSLC13A5) plasma membrane citrate transporter, a key metabolic regulator and energy sensor involved in health, longevity, and disease. Reduction of Indy gene activity in flies, and its homologs in worms, modulates metabolism and extends longevity. The metabolic changes are similar to what is obtained with caloric restriction (dietary restriction). Similar effects on metabolism have been observed in mice and rats. As a citrate transporter, INDY regulates cytoplasmic citrate levels. Indy flies heterozygous for a P-element insertion have increased spontaneous physical activity, increased fecundity, reduced insulin signaling, increased mitochondrial biogenesis, preserved intestinal stem cell homeostasis, lower lipid levels, and increased stress resistance. Mammalian Indy knockout (mIndy-KO) mice have higher sensitivity to insulin signaling, lower blood pressure and heart rate, preserved memory and are protected from the negative effects of a high-fat diet and some of the negative effects of aging. Reducing mIndy expression in human hepatocarcinoma cells has recently been shown to inhibit cell proliferation. Reduced Indy expression in the fly intestine affects intestinal stem cell proliferation, and has recently been shown to also inhibit germ cell proliferation in males with delayed sperm maturation and decreased spermatocyte numbers. These results highlight a new connection between energy metabolism and cell proliferation. The overrall picture in a variety of species points to a conserved role of INDY for metabolism and health. This is illustrated by an association of high mIndy gene expression with non-alcoholic fatty liver disease in obese humans. mIndy (mSLC13A5) coding region mutations (e.g., loss-of-function) are also associated with adverse effects in humans, such as autosomal recessive early infantile epileptic encephalopathy and Kohlschütter−Tönz syndrome. The recent findings illustrate the importance of mIndy gene for human health and disease. Furthermore, recent work on small-molecule regulators of INDY highlights the promise of INDY-based treatments for ameliorating disease and promoting healthy aging.
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Affiliation(s)
- Dushyant Mishra
- Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
| | - Kavitha Kannan
- Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
| | - Kali Meadows
- Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
| | - Jacob Macro
- Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
| | - Michael Li
- Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
| | - Stewart Frankel
- Department of Biology, University of Hartford, West Hartford, CT, United States
| | - Blanka Rogina
- Department of Genetics and Genome Sciences, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States.,Institute for Systems Genomics, School of Medicine, University of Connecticut Health Center, Farmington, CT, United States
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Wee NK, Sims NA, Morello R. The Osteocyte Transcriptome: Discovering Messages Buried Within Bone. Curr Osteoporos Rep 2021; 19:604-615. [PMID: 34757588 PMCID: PMC8720072 DOI: 10.1007/s11914-021-00708-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/24/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE OF THE REVIEW Osteocytes are cells embedded within the bone matrix, but their function and specific patterns of gene expression remain only partially defined; this is beginning to change with recent studies using transcriptomics. This unbiased approach can generate large amounts of data and is now being used to identify novel genes and signalling pathways within osteocytes both at baseline conditions and in response to stimuli. This review outlines the methods used to isolate cell populations containing osteocytes, and key recent transcriptomic studies that used osteocyte-containing preparations from bone tissue. RECENT FINDINGS Three common methods are used to prepare samples to examine osteocyte gene expression: digestion followed by sorting, laser capture microscopy, and the isolation of cortical bone shafts. All these methods present challenges in interpreting the data generated. Genes previously not known to be expressed by osteocytes have been identified and variations in osteocyte gene expression have been reported with age, sex, anatomical location, mechanical loading, and defects in bone strength. A substantial proportion of newly identified transcripts in osteocytes remain functionally undefined but several have been cross-referenced with functional data. Future work and improved methods (e.g. scRNAseq) likely provide useful resources for the study of osteocytes and important new information on the identity and functions of this unique cell type within the skeleton.
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Affiliation(s)
- Natalie Ky Wee
- Bone Cell Biology and Disease Unit, St Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, 3065, Australia
| | - Natalie A Sims
- Bone Cell Biology and Disease Unit, St Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, 3065, Australia
- Department of Medicine, The University of Melbourne, St. Vincent's Hospital, Melbourne, 3065, Australia
| | - Roy Morello
- Department of Physiology & Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
- Department of Orthopaedic Surgery, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
- Division of Genetics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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