1
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Dinesh NEH, Baratang N, Rosseau J, Mohapatra R, Li L, Mahalingam R, Tiedemann K, Campeau PM, Reinhardt DP. Fibronectin isoforms promote postnatal skeletal development. Matrix Biol 2024; 133:86-102. [PMID: 39159790 DOI: 10.1016/j.matbio.2024.08.002] [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: 04/11/2024] [Revised: 08/02/2024] [Accepted: 08/12/2024] [Indexed: 08/21/2024]
Abstract
Fibronectin (FN) is a ubiquitous extracellular matrix glycoprotein essential for the development of various tissues. Mutations in FN cause a unique form of spondylometaphyseal dysplasia, emphasizing its importance in cartilage and bone development. However, the relevance and functional role of FN during skeletal development has remained elusive. To address these aspects, we have generated conditional knockout mouse models targeting the cellular FN isoform in cartilage (cFNKO), the plasma FN isoform in hepatocytes (pFNKO), and both isoforms together in a double knockout (FNdKO). We used these mice to determine the relevance of the two principal FN isoforms in skeletal development from postnatal day one to the adult stage at two months. We identified a distinct topological FN deposition pattern in the mouse limb during different gestational and postnatal skeletal development phases, with prominent levels at the resting and hypertrophic chondrocyte zones and in the trabecular bone. Cartilage-specific cFN emerged as the predominant isoform in the growth plate, whereas circulating pFN remained excluded from the growth plate and confined to the primary and secondary ossification centers. Deleting either isoform independently (cFNKO or pFNKO) yielded only relatively subtle changes in the analyzed skeletal parameters. However, the double knockout of cFN in the growth plate and pFN in the circulation of the FNdKO mice significantly reduced postnatal body weight, body length, and bone length. Micro-CT analysis of the adult bone microarchitecture in FNdKO mice exposed substantial reductions in trabecular bone parameters and bone mineral density. The mice also showed elevated bone marrow adiposity. Analysis of chondrogenesis in FNdKO mice demonstrated changes in the resting, proliferating and hypertrophic growth plate zones, consistent alterations in chondrogenic markers such as collagen type II and X, decreased apoptosis of hypertrophic chondrocytes, and downregulation of bone formation markers. Transforming growth factor-β1 and downstream phospho-AKT levels were significantly lower in the FNdKO than in the control mice, revealing a crucial FN-mediated regulatory pathway in chondrogenesis and bone formation. In conclusion, the data demonstrate that FN is essential for chondrogenesis and bone development. Even though cFN and pFN act in different regions of the bone, both FN isoforms are required for the regulation of chondrogenesis, cartilage maturation, trabecular bone formation, and overall skeletal growth.
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Affiliation(s)
- Neha E H Dinesh
- Faculty of Medicine and Health Sciences, Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | | | | | - Ronit Mohapatra
- Faculty of Medicine and Health Sciences, Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Ling Li
- Faculty of Medicine and Health Sciences, Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Ramshaa Mahalingam
- Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada
| | | | | | - Dieter P Reinhardt
- Faculty of Medicine and Health Sciences, Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada.
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2
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Jia S, Liu W, Zhang M, Wang L, Ren C, Feng C, Zhang T, Lv H, Hou Z, Zou W, Zhang Y, Tong W, Wang J, Chen W. Insufficient Mechanical Loading Downregulates Piezo1 in Chondrocytes and Impairs Fracture Healing Through ApoE-Induced Senescence. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2400502. [PMID: 39418070 DOI: 10.1002/advs.202400502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 08/10/2024] [Indexed: 10/19/2024]
Abstract
Insufficient mechanical loading impairs fracture healing; however, the underlying mechanisms remain unclear. Increasing evidence indicates that Piezo1 plays an important role in fracture healing, although the effect of Piezo1 on the endochondral ossification of chondrocytes has been overlooked. This study reports that mechanical unloading down-regulates the expression of Piezo1 in chondrocytes and leads to fracture nonunion. Single-cell sequencing of calluses revealed that specific deletion of Piezo1 in chondrocytes upregulated the expression of apolipoprotein E (ApoE) in hypertrophic chondrocytes, resulting in delayed cartilage-to-bone transition due to enhanced chondrocyte senescence. Based on these results, an injectable and thermosensitive hydrogel is developed, which released an ApoE antagonist in situ at the fracture site. This hydrogel effectively attenuated chondrocyte senescence and, thus, promoted cartilage-to-bone transition as well as the fracture healing process. Overall, this data provide a new perspective on the activity of chondrocytes in fracture healing and a new direction for the treatment of fracture nonunion caused by insufficient mechanical loading.
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Affiliation(s)
- Siming Jia
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
- Hebei Medical University Clinical Medicine Postdoctoral Station (Hebei Medical University Third Hospital), Shijiazhuang, Hebei, 050051, China
| | - Weijian Liu
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Mo Zhang
- Hebei Medical University Clinical Medicine Postdoctoral Station (Hebei Medical University Third Hospital), Shijiazhuang, Hebei, 050051, China
- School of Pharmacy, Key Laboratory of Innovative Drug Development and Evaluation, Hebei Medical University, Shijiazhuang, 050017, China
| | - Lijun Wang
- Hainan Institute of Regenerative Orthopedics and Sports Medicine, Hainan Academy of Medical Sciences and School of Basic Medicine, Hainan Medical University, Hainan, 570000, China
- Key Laboratory of RNA Innovation, Science and Engineering, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Chuan Ren
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Chen Feng
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Tao Zhang
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Hongzhi Lv
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Zhiyong Hou
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Weiguo Zou
- Hainan Institute of Regenerative Orthopedics and Sports Medicine, Hainan Academy of Medical Sciences and School of Basic Medicine, Hainan Medical University, Hainan, 570000, China
- Key Laboratory of RNA Innovation, Science and Engineering, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yingze Zhang
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Wei Tong
- Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, 430022, China
| | - Juan Wang
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
| | - Wei Chen
- Department of Orthopaedic Surgery, NHC Key Laboratory of Intelligent Orthopaedic Equipment, Hebei Medical University Third Hospital, Shijiazhuang, Hebei, 050051, China
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3
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Melis S, Trompet D, Chagin AS, Maes C. Skeletal stem and progenitor cells in bone physiology, ageing and disease. Nat Rev Endocrinol 2024:10.1038/s41574-024-01039-y. [PMID: 39379711 DOI: 10.1038/s41574-024-01039-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/30/2024] [Indexed: 10/10/2024]
Abstract
Skeletal stem cells (SSCs) and related progenitors with osteogenic potential, collectively termed skeletal stem and/or progenitor cells (SSPCs), are crucial for providing osteoblasts for bone formation during homeostatic tissue turnover and fracture repair. Besides mediating normal bone physiology, they also have important roles in various metabolic bone diseases, including osteoporosis. SSPCs are of tremendous interest because they represent prime future targets for osteoanabolic therapies and bone regenerative medicine. Remarkable progress has been made in characterizing various SSC and SSPC populations in postnatal bone. SSPCs exist in the periosteum and within the bone marrow stroma, including subsets localizing around arteriolar and sinusoidal blood vessels; they can display osteogenic, chondrogenic, adipogenic and/or fibroblastic potential, and exert critical haematopoiesis-supportive functions. However, much remains to be clarified. By the current markers, bona fide SSCs are commonly contained within broader SSPC populations characterized by considerable heterogeneity and overlap, whose common versus specific functions in health and disease have not been fully unravelled. Here, we review the present knowledge of the identity, fates and relationships of SSPC populations in the postnatal bone environment, their contributions to bone maintenance, the changes observed upon ageing, and the effect of metabolic diseases such as osteoporosis and diabetes mellitus.
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Affiliation(s)
- Seppe Melis
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Dana Trompet
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, KU Leuven, Leuven, Belgium
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Andrei S Chagin
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Christa Maes
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, KU Leuven, Leuven, Belgium.
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Bian F, Hansen V, Feng HC, He J, Chen Y, Feng K, Ebrahimi B, Gray RS, Chai Y, Wu CL, Liu Z. The G protein-coupled receptor ADGRG6 maintains mouse growth plate homeostasis through IHH Signaling. J Bone Miner Res 2024:zjae144. [PMID: 39236220 DOI: 10.1093/jbmr/zjae144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 07/31/2024] [Accepted: 09/04/2024] [Indexed: 09/07/2024]
Abstract
The cartilage growth plate is essential for maintaining skeletal growth; however, the mechanisms governing postnatal growth plate homeostasis are still poorly understood. Using approaches of molecular mouse genetics and spatial transcriptomics applied to formalin-fixed, paraffin-embedded (FFPE) tissues, we show that ADGRG6/GPR126, a cartilage-enriched adhesion G protein-coupled receptor (GPCR), is essential for maintaining slow-cycling resting zone cells, appropriate chondrocyte proliferation and differentiation, and growth plate homeostasis in mice. Constitutive ablation of Adgrg6 in osteochondral progenitor cells with Col2a1Cre leads to a shortened resting zone, formation of cell clusters within the proliferative zone, and an elongated hypertrophic growth plate, marked by limited expression of PTHrP but increased IHH signaling throughout the growth plate. Attenuation of Smoothened (SMO)-dependent hedgehog signaling restored the Adgrg6 deficiency-induced expansion of hypertrophic chondrocytes, confirming that IHH signaling can promote chondrocyte hypertrophy in a PTHrP-independent manner. In contrast, postnatal ablation of Adgrg6 in mature chondrocytes with AcanCreERT2, induced after the formation of the resting zone, does not affect PTHrP expression but causes an overall reduction of growth plate thickness marked by increased cell death specifically in the resting zone cells and a general reduction of chondrocyte proliferation and differentiation. Spatial transcriptomics reveals that ADGRG6 is essential for maintaining chondrocyte homeostasis by regulating osteogenic and catabolic genes in all the zones of the postnatal growth plates, potentially through positive regulation of SOX9 expression. Our findings elucidate the essential role of a cartilage-enriched adhesion GPCR in regulating cell proliferation and hypertrophic differentiation by regulation of PTHrP/IHH signaling, maintenance of slow-cycle resting zone chondrocytes, and safeguarding chondrocyte homeostasis in postnatal mouse growth plates.
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Affiliation(s)
- Fangzhou Bian
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
| | - Victoria Hansen
- Center for Musculoskeletal Research, Department of Orthopedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY 14642, United States
| | - Hong Colleen Feng
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
| | - Jingyu He
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
| | - Yanshi Chen
- Center for Musculoskeletal Research, Department of Orthopedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY 14642, United States
- Department of Biology, University of Rochester, Rochester, NY 14642, United States
| | - Kaining Feng
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
| | - Brenda Ebrahimi
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
| | - Ryan S Gray
- Department of Nutritional Sciences, Dell Pediatric Research Institute, The University of Texas at Austin, Austin, TX 78723, United States
| | - Yang Chai
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
| | - Chia-Lung Wu
- Center for Musculoskeletal Research, Department of Orthopedics and Rehabilitation, University of Rochester Medical Center, Rochester, NY 14642, United States
| | - Zhaoyang Liu
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, United States
- Department of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, United States
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5
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Dinesh NEH, Campeau PM, Reinhardt DP. The Integral Role of Fibronectin in Skeletal Morphogenesis and Pathogenesis. Matrix Biol 2024:S0945-053X(24)00112-4. [PMID: 39232994 DOI: 10.1016/j.matbio.2024.08.010] [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: 05/29/2024] [Revised: 08/27/2024] [Accepted: 08/30/2024] [Indexed: 09/06/2024]
Abstract
Fibronectin (FN) serves as a critical organizer of extracellular matrix networks in two principal isoforms, the plasma FN and the cellular FN. While FN's pivotal role in various organ systems, including the blood vasculature, is well-established, its contribution to the development of the skeletal system is much less explored. Furthermore, the pathomechanisms of spondyloepiphyseal dysplasia caused by FN mutations remain elusive. In this minireview, we discuss findings from our recent two studies using i) an iPSC-based cell culture model to explore how FN mutations in spondyloepiphyseal dysplasia impact mesenchymal cell differentiation into chondrocytes and ii) conditional FN knockout mouse models to determine the physiological roles of FN isoforms during postnatal skeletal development. The data revealed that FN mutations cause severe intracellular and matrix defects in mesenchymal cells and impair their ability to differentiate into chondrocytes. The findings further demonstrate the important roles of both FN isoforms in orchestrating regulated chondrogenesis during skeletal development. We critically discuss the findings in the context of the existing literature.
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Affiliation(s)
- Neha E H Dinesh
- Faculty of Medicine and Health Sciences, Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | | | - Dieter P Reinhardt
- Faculty of Medicine and Health Sciences, Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC, Canada.
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6
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Tak HJ, Moon JW, Kim JY, Kang SH, Lee SH. Transition of endochondral bone formation at the normal and botulinum-treated mandibular condyle of growing juvenile rat. Arch Oral Biol 2024; 164:105999. [PMID: 38815512 DOI: 10.1016/j.archoralbio.2024.105999] [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: 03/19/2024] [Revised: 05/06/2024] [Accepted: 05/07/2024] [Indexed: 06/01/2024]
Abstract
OBJECTIVE The aim of this study was to understand the temporal and spatial distribution of canonical endochondral ossification (CEO) and non-canonical endochondral ossification (NCEO) of the normal growing rat condyle, and to evaluate their histomorphological changes following the simultaneous hypotrophy of the unilateral masticatory closing muscles with botulinum toxin (BTX). DESIGN 46 rats at postnatal 4 weeks were used for the experiment and euthanized at postnatal 4, 8, and 16 weeks. The right masticatory muscles of rats in experimental group were injected with BTX, the left being injected with saline as a control. The samples were evaluated using 3D morphometric, histological, and immunohistochemical analysis with three-dimensional regional mapping of endochondral ossifications. RESULTS The results showed that condylar endochondral ossification changed from CEO to NCEO at the main articulating surface during the experimental period and that the BTX-treated condyle presented a retroclined smaller condyle with an anteriorly-shifted narrower articulating surface. This articulating region showed a thinner layer of the endochondral cells, and a compact distribution of flattened cells. These were related to the load concentration, decreased cellular proliferation with thin cellular layers, reduced extracellular matrix, increased cellular differentiation toward the osteoblastic bone formation, and accelerated transition of the ossification types from CEO to NCEO. CONCLUSION The results suggest that endochondral ossification under loading tended to show more NCEO, and that masticatory muscular hypofunction by BTX had deleterious effects on endochondral bone formation and changed the condylar growth vector, resulting in a retroclined, smaller, asymmetrical, and deformed condyle with thin cartilage.
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Affiliation(s)
- Hye-Jin Tak
- Oral Science Research Center, Yonsei University, College of Dentistry, Seoul, the Republic of Korea
| | - Joo-Won Moon
- Oral Science Research Center, Yonsei University, College of Dentistry, Seoul, the Republic of Korea
| | - Jae-Young Kim
- Dept. of Oral and Maxillofacial Surgery, Yonsei University, College of Dentistry, Seoul, the Republic of Korea
| | - Sang-Hoon Kang
- Dept. of Oral and Maxillofacial Surgery, National Health Insurance Service Ilsan Hospital, Goyang, the Republic of Korea
| | - Sang-Hwy Lee
- Oral Science Research Center, Yonsei University, College of Dentistry, Seoul, the Republic of Korea; Dept. of Oral and Maxillofacial Surgery, Yonsei University, College of Dentistry, Seoul, the Republic of Korea.
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7
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Dima O, Didilescu AC, Manole CC, Pameijer C, Călin C. Synthetic composites versus calcium phosphate cements in bone regeneration: A narrative review. Ann Anat 2024; 255:152273. [PMID: 38754741 DOI: 10.1016/j.aanat.2024.152273] [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: 05/03/2024] [Accepted: 05/09/2024] [Indexed: 05/18/2024]
Abstract
BACKGROUND When the natural process of bone remodeling is disturbed, the need arises for a stimulant material in order to enhance the formation of a new healthy and strong osseous tissue to replace the damaged one. Recent studies have reported synthetic biomaterials to be a very good option for supporting bone regeneration. STUDY DESIGN Narrative review. OBJECTIVE This review aims to provide a brief presentation of two of the most recently developed synthetic biomaterials, i.e. calcium phosphate cements and synthetic composites, that are currently being used in bone regeneration with promising results. METHODS Literature searches using broad terms such as "bone regeneration," "biomaterials," "synthetic composites" and "calcium phosphate cements" were performed using PubMed. The osteal cells state of the art was explored by searching topic-specific full text keywords using Google Scholar. CONCLUSIONS Synthetic polymers such as PCL (poly-ε-caprolactone) and PLGA (poly lactic-co-glycolic acid) can improve the effectiveness of biomaterials like HA (hydroxyapatite) and BG (bioglass). Calcium phosphate, although being a suitable material for stimulating bone regeneration, needs an adjuvant in order to be effective in larger bone defects.
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Affiliation(s)
- Oana Dima
- Department of Embryology, Faculty of Dentistry, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | - Andreea Cristiana Didilescu
- Department of Embryology, Faculty of Dentistry, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
| | - Claudiu Constantin Manole
- Department of Biophysics, Faculty of Dentistry, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
| | - Cornelis Pameijer
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut, Farmington, USA
| | - Claudiu Călin
- Department of Embryology, Faculty of Dentistry, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
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8
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Angelozzi M, Karvande A, Lefebvre V. SOXC are critical regulators of adult bone mass. Nat Commun 2024; 15:2956. [PMID: 38580651 PMCID: PMC10997656 DOI: 10.1038/s41467-024-47413-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 03/28/2024] [Indexed: 04/07/2024] Open
Abstract
Pivotal in many ways for human health, the control of adult bone mass is governed by complex, incompletely understood crosstalk namely between mesenchymal stem cells, osteoblasts and osteoclasts. The SOX4, SOX11 and SOX12 (SOXC) transcription factors were previously shown to control many developmental processes, including skeletogenesis, and SOX4 was linked to osteoporosis, but how SOXC control adult bone mass remains unknown. Using SOXC loss- and gain-of-function mouse models, we show here that SOXC redundantly promote prepubertal cortical bone mass strengthening whereas only SOX4 mitigates adult trabecular bone mass accrual in early adulthood and subsequent maintenance. SOX4 favors bone resorption over formation by lowering osteoblastogenesis and increasing osteoclastogenesis. Single-cell transcriptomics reveals its prevalent expression in Lepr+ mesenchymal cells and ability to upregulate genes for prominent anti-osteoblastogenic and pro-osteoclastogenic factors, including interferon signaling-related chemokines, contributing to these adult stem cells' secretome. SOXC, with SOX4 predominantly, are thus key regulators of adult bone mass.
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Affiliation(s)
- Marco Angelozzi
- Department of Surgery, Division of Orthopaedics, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
| | - Anirudha Karvande
- Department of Surgery, Division of Orthopaedics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Véronique Lefebvre
- Department of Surgery, Division of Orthopaedics, Children's Hospital of Philadelphia, Philadelphia, PA, USA.
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9
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Rashid H, Smith CM, Convers V, Clark K, Javed A. Runx2 deletion in hypertrophic chondrocytes impairs osteoclast mediated bone resorption. Bone 2024; 181:117014. [PMID: 38218304 PMCID: PMC10922707 DOI: 10.1016/j.bone.2024.117014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 12/27/2023] [Accepted: 01/05/2024] [Indexed: 01/15/2024]
Abstract
Deletion of Runx2 gene in proliferating chondrocytes results in complete failure of endochondral ossification and perinatal lethality. We reported recently that mice with Runx2 deletion specifically in hypertrophic chondrocytes (HCs) using the Col10a1-Cre transgene survive and exhibit enlarged growth plates due to decreased HC apoptosis and cartilage resorption. Bulk of chondrogenesis occurs postnatally, however, the role of Runx2 in HCs during postnatal chondrogenesis is unknown. Despite limb dwarfism, adult homozygous (Runx2HC/HC) mice showed a significant increase in length of growth plate and articular cartilage. Consistent with doubling of the hypertrophic zone, collagen type X expression was increased in Runx2HC/HC mice. In sharp contrast, expression of metalloproteinases and aggrecanases were markedly decreased. Impaired cartilage degradation was evident by the retention of significant amount of safranin-O positive cartilage. Histomorphometry and μCT uncovered increased trabecular bone mass with a significant increase in BV/TV ratio, trabecular number, thickness, and a decrease in trabecular space in Runx2HC/HC mice. To identify if this is due to increased bone synthesis, expression of osteoblast differentiation markers was evaluated and found to be comparable amongst littermates. Histomorphometry confirmed similar number of osteoblasts in the littermates. Furthermore, dynamic bone synthesis showed no differences in mineral apposition or bone formation rates. Surprisingly, three-point-bending test revealed Runx2HC/HC bones to be structurally less strong. Interestingly, both the number and surface of osteoclasts were markedly reduced in Runx2HC/HC littermates. Rankl and IL-17a ligands that promote osteoclast differentiation were markedly reduced in Runx2HC/HC mice. Bone marrow cultures were performed to independently establish Runx2 and hypertrophic chondrocytes role in osteoclast development. The culture from the Runx2HC/HC mice formed significantly fewer and smaller osteoclasts. The expression of mature osteoclast markers, Ctsk and Mmp9, were significantly reduced in the cultures from Runx2HC/HC mice. Thus, Runx2 functions extend beyond embryonic development and chondrocyte hypertrophy by regulating cartilage degradation, osteoclast differentiation, and bone resorption during postnatal endochondral ossification.
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Affiliation(s)
- Harunur Rashid
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham 35233, AL, USA
| | - Caris M Smith
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham 35233, AL, USA
| | - Vashti Convers
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham 35233, AL, USA
| | - Katelynn Clark
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham 35233, AL, USA
| | - Amjad Javed
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham 35233, AL, USA.
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10
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Dong X, Leary JR, Yang C, Brusko MA, Brusko TM, Bacher R. Data-driven selection of analysis decisions in single-cell RNA-seq trajectory inference. Brief Bioinform 2024; 25:bbae216. [PMID: 38725155 PMCID: PMC11082074 DOI: 10.1093/bib/bbae216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 03/01/2024] [Accepted: 04/25/2024] [Indexed: 05/13/2024] Open
Abstract
Single-cell RNA sequencing (scRNA-seq) experiments have become instrumental in developmental and differentiation studies, enabling the profiling of cells at a single or multiple time-points to uncover subtle variations in expression profiles reflecting underlying biological processes. Benchmarking studies have compared many of the computational methods used to reconstruct cellular dynamics; however, researchers still encounter challenges in their analysis due to uncertainty with respect to selecting the most appropriate methods and parameters. Even among universal data processing steps used by trajectory inference methods such as feature selection and dimension reduction, trajectory methods' performances are highly dataset-specific. To address these challenges, we developed Escort, a novel framework for evaluating a dataset's suitability for trajectory inference and quantifying trajectory properties influenced by analysis decisions. Escort evaluates the suitability of trajectory analysis and the combined effects of processing choices using trajectory-specific metrics. Escort navigates single-cell trajectory analysis through these data-driven assessments, reducing uncertainty and much of the decision burden inherent to trajectory inference analyses. Escort is implemented in an accessible R package and R/Shiny application, providing researchers with the necessary tools to make informed decisions during trajectory analysis and enabling new insights into dynamic biological processes at single-cell resolution.
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Affiliation(s)
- Xiaoru Dong
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, United States
| | - Jack R Leary
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, United States
| | - Chuanhao Yang
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, United States
| | - Maigan A Brusko
- Diabetes Institute, University of Florida, Gainesville, FL 32610, United States
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610, United States
| | - Todd M Brusko
- Diabetes Institute, University of Florida, Gainesville, FL 32610, United States
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610, United States
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL 32610, United States
| | - Rhonda Bacher
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, United States
- Diabetes Institute, University of Florida, Gainesville, FL 32610, United States
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11
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Matsushita Y, Liu J, Chu AKY, Ono W, Welch JD, Ono N. Endosteal stem cells at the bone-blood interface: A double-edged sword for rapid bone formation: Bone marrow endosteal stem cells provide a robust source of bone-making osteoblasts both in normal and abnormal bone formation. Bioessays 2024; 46:e2300173. [PMID: 38161246 DOI: 10.1002/bies.202300173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 12/17/2023] [Accepted: 12/18/2023] [Indexed: 01/03/2024]
Abstract
Endosteal stem cells are a subclass of bone marrow skeletal stem cell populations that are particularly important for rapid bone formation occurring in growth and regeneration. These stem cells are strategically located near the bone surface in a specialized microenvironment of the endosteal niche. These stem cells are abundant in young stages but eventually depleted and replaced by other stem cell types residing in a non-endosteal perisinusoidal niche. Single-cell molecular profiling and in vivo cell lineage analyses play key roles in discovering endosteal stem cells. Importantly, endosteal stem cells can transform into bone tumor-making cells when deleterious mutations occur in tumor suppressor genes. The emerging hypothesis is that osteoblast-chondrocyte transitional identities confer a special subset of endosteal stromal cells with stem cell-like properties, which may make them susceptible for tumorigenic transformation. Endosteal stem cells are likely to represent an important therapeutic target of bone diseases caused by aberrant bone formation.
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Affiliation(s)
- Yuki Matsushita
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Jialin Liu
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Angel Ka Yan Chu
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Wanida Ono
- University of Texas Health Science Center at Houston School of Dentistry, Houston, Texas, USA
| | - Joshua D Welch
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Noriaki Ono
- University of Texas Health Science Center at Houston School of Dentistry, Houston, Texas, USA
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12
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Yang G, He Q, Guo X, Li RY, Lin J, Lang Y, Tao W, Liu W, Lin H, Xing S, Qi Y, Xie Z, Han JDJ, Zhou B, Teng Y, Yang X. Identification of the metaphyseal skeletal stem cell building trabecular bone. SCIENCE ADVANCES 2024; 10:eadl2238. [PMID: 38394209 PMCID: PMC10889359 DOI: 10.1126/sciadv.adl2238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Accepted: 01/22/2024] [Indexed: 02/25/2024]
Abstract
Skeletal stem cells (SSCs) that are capable of self-renewal and multipotent differentiation contribute to bone development and homeostasis. Several populations of SSCs at different skeletal sites have been reported. Here, we identify a metaphyseal SSC (mpSSC) population whose transcriptional landscape is distinct from other bone mesenchymal stromal cells (BMSCs). These mpSSCs are marked by Sstr2 or Pdgfrb+Kitl-, located just underneath the growth plate, and exclusively derived from hypertrophic chondrocytes (HCs). These HC-derived mpSSCs have properties of self-renewal and multipotency in vitro and in vivo, producing most HC offspring postnatally. HC-specific deletion of Hgs, a component of the endosomal sorting complex required for transport, impairs the HC-to-mpSSC conversion and compromises trabecular bone formation. Thus, mpSSC is the major source of BMSCs and osteoblasts in bone marrow, supporting the postnatal trabecular bone formation.
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Affiliation(s)
- Guan Yang
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Qi He
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
- Bioinformatics Center of AMMS, Beijing 100850, China
| | - Xiaoxiao Guo
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Center for Quantitative Biology (CQB), Peking University, Beijing 100871, China
| | - Rong-Yu Li
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Jingting Lin
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Yiming Lang
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Wanyu Tao
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Center for Quantitative Biology (CQB), Peking University, Beijing 100871, China
| | - Wenjia Liu
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Huisang Lin
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Shilai Xing
- School of Ophthalmology & Optometry and Eye Hospital, Institute of Biomedical Big Data, Wenzhou Medical University, Wenzhou 325027, China
| | - Yini Qi
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Zhongliang Xie
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Jing-Dong J. Han
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Center for Quantitative Biology (CQB), Peking University, Beijing 100871, China
| | - Bin Zhou
- New Cornerstone Science Laboratory, State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yan Teng
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
| | - Xiao Yang
- State Key Laboratory of Medical Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing 102206, China
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13
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Yu H, Khanshour AM, Ushiki A, Otomo N, Koike Y, Einarsdottir E, Fan Y, Antunes L, Kidane YH, Cornelia R, Sheng RR, Zhang Y, Pei J, Grishin NV, Evers BM, Cheung JPY, Herring JA, Terao C, Song YQ, Gurnett CA, Gerdhem P, Ikegawa S, Rios JJ, Ahituv N, Wise CA. Association of genetic variation in COL11A1 with adolescent idiopathic scoliosis. eLife 2024; 12:RP89762. [PMID: 38277211 PMCID: PMC10945706 DOI: 10.7554/elife.89762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024] Open
Abstract
Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than fivefold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here, we sought to define the roles of PAX1 and newly identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 10,519 individuals with AIS and 93,238 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (α1) XI (rs3753841; NM_080629.2_c.4004C>T; p.(Pro1335Leu); p=7.07E-11, OR = 1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice (Pax1-/-). In postnatal spines we found that PAX1 and collagen (α1) XI protein both localize within the intervertebral disc-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1-/- spines compared to wild-type. By genetic targeting we found that wild-type Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, the latter suppression was abrogated in the presence of the AIS-associated COL11A1P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2 or tamoxifen treatment significantly altered Col11a1 and Mmp3 expression in chondrocytes. We propose a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a PAX1-COL11a1-MMP3 signaling axis in spinal chondrocytes.
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Affiliation(s)
- Hao Yu
- Center for Translational Research, Scottish Rite for ChildrenDallasUnited States
| | - Anas M Khanshour
- Center for Translational Research, Scottish Rite for ChildrenDallasUnited States
| | - Aki Ushiki
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
- Institute for Human Genetics, University of California, San FranciscoSan FranciscoUnited States
| | - Nao Otomo
- Laboratory of Bone and Joint Diseases, RIKEN Center for Integrative Medical SciencesTokyoJapan
| | - Yoshinao Koike
- Laboratory of Bone and Joint Diseases, RIKEN Center for Integrative Medical SciencesTokyoJapan
- Laboratory for Statistical and Translational Genetics, RIKEN Center for Integrative Medical SciencesYokohamaJapan
| | - Elisabet Einarsdottir
- Science for Life Laboratory, Department of Gene Technology, KTH-Royal Institute of TechnologySolnaSweden
| | - Yanhui Fan
- School of Biomedical Sciences, The University of Hong KongHong Kong SARChina
| | - Lilian Antunes
- Department of Neurology, Washington University in St. LouisSt. LouisUnited States
| | - Yared H Kidane
- Center for Translational Research, Scottish Rite for ChildrenDallasUnited States
| | - Reuel Cornelia
- Center for Translational Research, Scottish Rite for ChildrenDallasUnited States
| | - Rory R Sheng
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
- Institute for Human Genetics, University of California, San FranciscoSan FranciscoUnited States
| | - Yichi Zhang
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
- Institute for Human Genetics, University of California, San FranciscoSan FranciscoUnited States
- School of Pharmaceutical Sciences, Tsinghua UniversityBeijingChina
| | - Jimin Pei
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Nick V Grishin
- Department of Biophysics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Bret M Evers
- Department of Pathology, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Ophthalmology, University of Texas Southwestern Medical CenterDallasUnited States
| | - Jason Pui Yin Cheung
- Department of Orthopaedics and Traumatology LKS Faculty of Medicine, The University of Hong KongHong Kong SARChina
| | - John A Herring
- Department of Orthopedic Surgery, Scottish Rite for ChildrenDallasUnited States
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical CenterDallasUnited States
| | - Chikashi Terao
- Laboratory for Statistical and Translational Genetics, RIKEN Center for Integrative Medical SciencesYokohamaJapan
| | - You-qiang Song
- School of Biomedical Sciences, The University of Hong KongHong Kong SARChina
| | - Christina A Gurnett
- Department of Neurology, Washington University in St. LouisSt. LouisUnited States
| | - Paul Gerdhem
- Department of Surgical Sciences, Uppsala UniversityUppsalaSweden
- Department of Orthopaedics and Hand Surgery, Uppsala University HospitalUppsalaSweden
- Department of Clinical Science, Intervention & Technology (CLINTEC), Karolinska Institutet, Stockholm, Uppsala UniversityUppsalaSweden
| | - Shiro Ikegawa
- Laboratory of Bone and Joint Diseases, RIKEN Center for Integrative Medical SciencesTokyoJapan
| | - Jonathan J Rios
- Center for Translational Research, Scottish Rite for ChildrenDallasUnited States
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical CenterDallasUnited States
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Pediatrics, University of Texas Southwestern Medical CenterDallasUnited States
| | - Nadav Ahituv
- Department of Bioengineering and Therapeutic Sciences, University of California, San FranciscoSan FranciscoUnited States
- Institute for Human Genetics, University of California, San FranciscoSan FranciscoUnited States
| | - Carol A Wise
- Center for Translational Research, Scottish Rite for ChildrenDallasUnited States
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical CenterDallasUnited States
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Pediatrics, University of Texas Southwestern Medical CenterDallasUnited States
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14
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Dong X, Leary JR, Yang C, Brusko MA, Brusko TM, Bacher R. Data-driven selection of analysis decisions in single-cell RNA-seq trajectory inference. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.572214. [PMID: 38187768 PMCID: PMC10769271 DOI: 10.1101/2023.12.18.572214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Single-cell RNA sequencing (scRNA-seq) experiments have become instrumental in developmental and differentiation studies, enabling the profiling of cells at a single or multiple time-points to uncover subtle variations in expression profiles reflecting underlying biological processes. Benchmarking studies have compared many of the computational methods used to reconstruct cellular dynamics, however researchers still encounter challenges in their analysis due to uncertainties in selecting the most appropriate methods and parameters. Even among universal data processing steps used by trajectory inference methods such as feature selection and dimension reduction, trajectory methods' performances are highly dataset-specific. To address these challenges, we developed Escort, a framework for evaluating a dataset's suitability for trajectory inference and quantifying trajectory properties influenced by analysis decisions. Escort navigates single-cell trajectory analysis through data-driven assessments, reducing uncertainty and much of the decision burden associated with trajectory inference. Escort is implemented in an accessible R package and R/Shiny application, providing researchers with the necessary tools to make informed decisions during trajectory analysis and enabling new insights into dynamic biological processes at single-cell resolution.
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Affiliation(s)
- Xiaoru Dong
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, USA
| | - Jack R. Leary
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, USA
| | - Chuanhao Yang
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, USA
| | - Maigan A. Brusko
- Diabetes Institute, University of Florida, Gainesville, FL 32610, USA
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Todd M. Brusko
- Diabetes Institute, University of Florida, Gainesville, FL 32610, USA
- Department of Pathology, Immunology, and Laboratory Medicine, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Department of Pediatrics, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Rhonda Bacher
- Department of Biostatistics, College of Public Health and Health Professions, University of Florida, Gainesville, FL 32610, USA
- Diabetes Institute, University of Florida, Gainesville, FL 32610, USA
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15
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Raimann A, Misof BM, Fratzl P, Fratzl-Zelman N. Bone Material Properties in Bone Diseases Affecting Children. Curr Osteoporos Rep 2023; 21:787-805. [PMID: 37897675 DOI: 10.1007/s11914-023-00822-6] [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] [Accepted: 09/12/2023] [Indexed: 10/30/2023]
Abstract
PURPOSE OF REVIEW Metabolic and genetic bone disorders affect not only bone mass but often also the bone material, including degree of mineralization, matrix organization, and lacunar porosity. The quality of juvenile bone is moreover highly influenced by skeletal growth. This review aims to provide a compact summary of the present knowledge on the complex interplay between bone modeling and remodeling during skeletal growth and to alert the reader to the complexity of bone tissue characteristics in children with bone disorders. RECENT FINDINGS We describe cellular events together with the characteristics of the different tissues and organic matrix organization (cartilage, woven and lamellar bone) occurring during linear growth. Subsequently, we present typical alterations thereof in disorders leading to over-mineralized bone matrix compared to those associated with low or normal mineral content based on bone biopsy studies. Growth spurts or growth retardation might amplify or mask disease-related alterations in bone material, which makes the interpretation of bone tissue findings in children complex and challenging.
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Affiliation(s)
- Adalbert Raimann
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Pulmonology, Allergology and Endocrinology, Medical University of Vienna, Vienna, Austria
- Vienna Bone and Growth Center, Vienna, Austria
| | - Barbara M Misof
- Vienna Bone and Growth Center, Vienna, Austria
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Center Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria
| | - Peter Fratzl
- Max Planck Institute of Colloids and Interfaces, Department of Biomaterials, Research Campus Golm, Potsdam, Germany
| | - Nadja Fratzl-Zelman
- Vienna Bone and Growth Center, Vienna, Austria.
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of OEGK and AUVA Trauma Center Meidling, 1st Medical Department, Hanusch Hospital, Vienna, Austria.
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16
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Chagin AS, Chu TL. The Origin and Fate of Chondrocytes: Cell Plasticity in Physiological Setting. Curr Osteoporos Rep 2023; 21:815-824. [PMID: 37837512 PMCID: PMC10724094 DOI: 10.1007/s11914-023-00827-1] [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: 09/26/2023] [Indexed: 10/16/2023]
Abstract
PURPOSE OF REVIEW Here, we discuss the origin of chondrocytes, their destiny, and their plasticity in relationship to bone growth, articulation, and formation of the trabeculae. We also consider these processes from a biological, clinical, and evolutionary perspective. RECENT FINDINGS Chondrocytes, which provide the template for the formation of most bones, are responsible for skeletal growth and articulation during postnatal life. In recent years our understanding of the fate of these cells has changed dramatically. Current evidence indicates a paradoxical situation during skeletogenesis, with some cells of mesenchymal condensation differentiating directly into osteoblasts, whereas others of the same kind give rise to highly similar osteoblasts via a complex process of differentiation involving several chondrocyte intermediates. The situation becomes even more paradoxical during postnatal growth when stem cells in the growth plate produce differentiated, functional progenies, which thereafter presumably dedifferentiate into another type of stem cell. Such a remarkable transition from one cell type to another under postnatal physiological conditions provides a fascinating example of cellular plasticity that may have valuable clinical implications.
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Affiliation(s)
- Andrei S Chagin
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden.
| | - Tsz Long Chu
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
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17
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Chen N, Wu RW, Lam Y, Chan WC, Chan D. Hypertrophic chondrocytes at the junction of musculoskeletal structures. Bone Rep 2023; 19:101698. [PMID: 37485234 PMCID: PMC10359737 DOI: 10.1016/j.bonr.2023.101698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/12/2023] [Accepted: 07/01/2023] [Indexed: 07/25/2023] Open
Abstract
Hypertrophic chondrocytes are found at unique locations at the junction of skeletal tissues, cartilage growth plate, articular cartilage, enthesis and intervertebral discs. Their role in the skeleton is best understood in the process of endochondral ossification in development and bone fracture healing. Chondrocyte hypertrophy occurs in degenerative conditions such as osteoarthritis. Thus, the role of hypertrophic chondrocytes in skeletal biology and pathology is context dependent. This review will focus on hypertrophic chondrocytes in endochondral ossification, in which they exist in a transient state, but acting as a central regulator of differentiation, mineralization, vascularization and conversion to bone. The amazing journey of a chondrocyte from being entrapped in the extracellular matrix environment to becoming proliferative then hypertrophic will be discussed. Recent studies on the dynamic changes and plasticity of hypertrophic chondrocytes have provided new insights into how we view these cells, not as terminally differentiated but as cells that can dedifferentiate to more progenitor-like cells in a transition to osteoblasts and adipocytes, as well as a source of skeletal stem and progenitor cells residing in the bone marrow. This will provide a foundation for studies of hypertrophic chondrocytes at other skeletal sites in development, tissue maintenance, pathology and therapy.
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Affiliation(s)
- Ning Chen
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Robin W.H. Wu
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Yan Lam
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Wilson C.W. Chan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
- Department of Orthopaedics Surgery and Traumatology, The University of Hong Kong-Shenzhen Hospital (HKU-SZH), Shenzhen 518053, China
| | - Danny Chan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
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18
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Yu H, Khanshour AM, Ushiki A, Otomo N, Koike Y, Einarsdottir E, Fan Y, Antunes L, Kidane YH, Cornelia R, Sheng R, Zhang Y, Pei J, Grishin NV, Evers BM, Cheung JPY, Herring JA, Terao C, Song YQ, Gurnett CA, Gerdhem P, Ikegawa S, Rios JJ, Ahituv N, Wise CA. Association of genetic variation in COL11A1 with adolescent idiopathic scoliosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.26.542293. [PMID: 37292598 PMCID: PMC10245954 DOI: 10.1101/2023.05.26.542293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than five-fold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the PAX1 gene. Here we sought to define the roles of PAX1 and newly-identified AIS-associated genes in the developmental mechanism of AIS. In a genetic study of 10,519 individuals with AIS and 93,238 unaffected controls, significant association was identified with a variant in COL11A1 encoding collagen (α1) XI (rs3753841; NM_080629.2_c.4004C>T; p.(Pro1335Leu); P=7.07e-11, OR=1.118). Using CRISPR mutagenesis we generated Pax1 knockout mice (Pax1-/-). In postnatal spines we found that PAX1 and collagen (α1) XI protein both localize within the intervertebral disc (IVD)-vertebral junction region encompassing the growth plate, with less collagen (α1) XI detected in Pax1-/- spines compared to wildtype. By genetic targeting we found that wildtype Col11a1 expression in costal chondrocytes suppresses expression of Pax1 and of Mmp3, encoding the matrix metalloproteinase 3 enzyme implicated in matrix remodeling. However, this suppression was abrogated in the presence of the AIS-associated COL11A1P1335L mutant. Further, we found that either knockdown of the estrogen receptor gene Esr2, or tamoxifen treatment, significantly altered Col11a1 and Mmp3 expression in chondrocytes. We propose a new molecular model of AIS pathogenesis wherein genetic variation and estrogen signaling increase disease susceptibility by altering a Pax1-Col11a1-Mmp3 signaling axis in spinal chondrocytes.
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Affiliation(s)
- Hao Yu
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Anas M Khanshour
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Aki Ushiki
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | - Nao Otomo
- Laboratory of Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, JP
| | - Yoshinao Koike
- Laboratory of Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, JP
- Laboratory for Statistical and Translational Genetics, RIKEN Center for Integrative Medical Sciences, Yokohama, JP
| | - Elisabet Einarsdottir
- Science for Life Laboratory, Department of Gene Technology, KTH-Royal Institute of Technology, Solna, SE
| | - Yanhui Fan
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, CN
| | - Lilian Antunes
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Yared H Kidane
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Reuel Cornelia
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Rory Sheng
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | - Yichi Zhang
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, CN
| | - Jimin Pei
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Nick V Grishin
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Bret M Evers
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jason Pui Yin Cheung
- Department of Orthopaedics and Traumatology LKS Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, CN
| | - John A Herring
- Department of Orthopedic Surgery, Scottish Rite for Children, Dallas, TX, USA
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chikashi Terao
- Laboratory for Statistical and Translational Genetics, RIKEN Center for Integrative Medical Sciences, Yokohama, JP
| | - You-Qiang Song
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong SAR, CN
| | - Christina A Gurnett
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Paul Gerdhem
- Department of Clinical Science, Intervention & Technology (CLINTEC), Karolinska Institutet, Stockholm, Uppsala University, Uppsala, SE
- Department of Surgical Sciences, Uppsala University and
- Department of Orthopaedics and Hand Surgery, Uppsala University Hospital, Uppsala, SE
| | - Shiro Ikegawa
- Laboratory of Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, JP
| | - Jonathan J Rios
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Nadav Ahituv
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | - Carol A Wise
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
- Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
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19
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Yadav PS, Papaioannou G, Kobelski MM, Demay MB. Phosphate-induced activation of VEGFR2 leads to caspase-9-mediated apoptosis of hypertrophic chondrocytes. iScience 2023; 26:107548. [PMID: 37636062 PMCID: PMC10450517 DOI: 10.1016/j.isci.2023.107548] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/21/2023] [Accepted: 08/02/2023] [Indexed: 08/29/2023] Open
Abstract
Low circulating phosphate (Pi) leads to rickets, characterized by expansion of the hypertrophic chondrocytes (HCs) in the growth plate due to impaired HC apoptosis. Studies in HCs demonstrate that Pi activates the Raf/MEK/ERK1/2 and mitochondrial apoptotic pathways. To determine how Pi activates these pathways, a small-molecule screen was undertaken to identify inhibitors of Pi-induced ERK1/2 phosphorylation in HCs. Vascular endothelial growth factor receptor 2 (VEGFR2) was identified as a target. In vitro studies in HCs demonstrate that VEGFR2 inhibitors block Pi-induced pERK1/2 and caspase-9 cleavage. Like Pi, rhVEGF activates ERK1/2 and caspase-9 in HCs and induces phosphorylation of VEGFR2, confirming that Pi activates this signaling pathway in HCs. Chondrocyte-specific depletion of VEGFR2 leads to an increase in HCs, impaired vascular invasion, and a decrease in HC apoptosis. Thus, these studies define a role for VEGFR2 in transducing Pi signals and mediating its effects on growth plate maturation.
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Affiliation(s)
- Prem Swaroop Yadav
- Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Garyfallia Papaioannou
- Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | | | - Marie B. Demay
- Endocrine Unit, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
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20
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Allen NB, Aitchison AH, Bagheri K, Guardino NJ, Abar B, Adams SB. Exposure of Tissue-Engineered Cartilage Analogs to Synovial Fluid Hematoma After Ankle Fracture Is Associated With Chondrocyte Death and Altered Cartilage Maintenance Gene Expression. Foot Ankle Int 2023; 44:922-930. [PMID: 37329280 DOI: 10.1177/10711007231178829] [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] [Indexed: 06/19/2023]
Abstract
BACKGROUND The first stage of fracture healing consists of hematoma formation with recruitment of proinflammatory cytokines and matrix metalloproteinases. Unfortunately, when there is an intra-articular fracture, these inflammatory mediators are not retained at the fracture site, but instead, envelop the healthy cartilage of the entire joint via the synovial fluid fracture hematoma (SFFH). These inflammatory cytokines and matrix metalloproteinases are known factors in the progression of osteoarthritis and rheumatoid arthritis. Despite the known inflammatory contents of the SFFH, little research has been done on the effects of the SFFH on healthy cartilage with regard to cell death and alteration in gene expression that could lead to posttraumatic osteoarthritis (PTOA). METHODS SFFH was collected from 12 patients with intraarticular ankle fracture at the time of surgery. Separately, C20A4 immortalized human chondrocytes were 3-dimensionally cultured to create scaffold-free cartilage tissue analogs (CTAs) to simulate healthy cartilage. Experimental CTAs (n = 12) were exposed to 100% SFFH for 3 days, washed, and transferred to complete media for 3 days. Control CTAs (n = 12) were simultaneously cultured in complete medium without exposure to SFFH. Subsequently, CTAs were harvested and underwent biochemical, histological, and gene expression analysis. RESULTS Exposure of CTAs to ankle SFFH for 3 days significantly decreased chondrocyte viability by 34% (P = .027). Gene expression of both COL2A1 and SOX9 were significantly decreased after exposure to SFFH (P = .012 and P = .0013 respectively), while there was no difference in COL1A1, RUNX2, and MMP13 gene expression. Quantitative analysis of Picrosirius red staining demonstrated increased collagen I deposition with poor ultrastructural organization in SFFH-exposed CTAs. CONCLUSION Exposure of an organoid model of healthy cartilage tissue to SFFH after intraarticular ankle fracture resulted in decreased chondrocyte viability, decreased expression of genes regulating normal chondrocyte phenotype, and altered matrix ultrastructure indicating differentiation toward an osteoarthritis phenotype. CLINICAL RELEVANCE The majority of ankle fracture open reduction and internal fixation does not occur immediately after fracture. In fact, typically these fractures are treated several days to weeks later in order to let the swelling subside. This means that the healthy innocent bystander cartilage not involved in the fracture is exposed to SFFH during this time. In this study, the SFFH caused decreased chondrocyte viability and specific altered gene expression that might have the potential to induce osteoarthritis. These data suggest that early intervention after intraarticular ankle fracture could possibly mitigate progression toward PTOA.
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Affiliation(s)
- Nicholas B Allen
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | | | - Kian Bagheri
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Nicholas J Guardino
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
| | - Bijan Abar
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
- Department of Mechanical Engineering and Material Science, Duke University, Durham, NC, USA
| | - Samuel B Adams
- Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
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21
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Wu S, Ohba S, Matsushita Y. Single-Cell RNA-Sequencing Reveals the Skeletal Cellular Dynamics in Bone Repair and Osteoporosis. Int J Mol Sci 2023; 24:9814. [PMID: 37372962 DOI: 10.3390/ijms24129814] [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: 04/28/2023] [Revised: 05/29/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
The bone is an important organ that performs various functions, and the bone marrow inside the skeleton is composed of a complex intermix of hematopoietic, vascular, and skeletal cells. Current single-cell RNA sequencing (scRNA-seq) technology has revealed heterogeneity and sketchy differential hierarchy of skeletal cells. Skeletal stem and progenitor cells (SSPCs) are located upstream of the hierarchy and differentiate into chondrocytes, osteoblasts, osteocytes, and bone marrow adipocytes. In the bone marrow, multiple types of bone marrow stromal cells (BMSCs), which have the potential of SSPCs, are spatiotemporally located in distinct areas, and SSPCs' potential shift of BMSCs may occur with the advancement of age. These BMSCs contribute to bone regeneration and bone diseases, such as osteoporosis. In vivo lineage-tracing technologies show that various types of skeletal lineage cells concomitantly gather and contribute to bone regeneration. In contrast, these cells differentiate into adipocytes with aging, leading to senile osteoporosis. scRNA-seq analysis has revealed that alteration in the cell-type composition is a major cause of tissue aging. In this review, we discuss the cellular dynamics of skeletal cell populations in bone homeostasis, regeneration, and osteoporosis.
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Affiliation(s)
- Sixun Wu
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
| | - Shinsuke Ohba
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
- Department of Tissue and Developmental Biology, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Yuki Matsushita
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
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22
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Lamandé SR, Ng ES, Cameron TL, Kung LHW, Sampurno L, Rowley L, Lilianty J, Patria YN, Stenta T, Hanssen E, Bell KM, Saxena R, Stok KS, Stanley EG, Elefanty AG, Bateman JF. Modeling human skeletal development using human pluripotent stem cells. Proc Natl Acad Sci U S A 2023; 120:e2211510120. [PMID: 37126720 PMCID: PMC10175848 DOI: 10.1073/pnas.2211510120] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 04/04/2023] [Indexed: 05/03/2023] Open
Abstract
Chondrocytes and osteoblasts differentiated from induced pluripotent stem cells (iPSCs) will provide insights into skeletal development and genetic skeletal disorders and will generate cells for regenerative medicine applications. Here, we describe a method that directs iPSC-derived sclerotome to chondroprogenitors in 3D pellet culture then to articular chondrocytes or, alternatively, along the growth plate cartilage pathway to become hypertrophic chondrocytes that can transition to osteoblasts. Osteogenic organoids deposit and mineralize a collagen I extracellular matrix (ECM), mirroring in vivo endochondral bone formation. We have identified gene expression signatures at key developmental stages including chondrocyte maturation, hypertrophy, and transition to osteoblasts and show that this system can be used to model genetic cartilage and bone disorders.
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Affiliation(s)
- Shireen R. Lamandé
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Elizabeth S. Ng
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Trevor L. Cameron
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Louise H. W. Kung
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Lisa Sampurno
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Lynn Rowley
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Jinia Lilianty
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
| | - Yudha Nur Patria
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
- Department of Child Health, Universitas Gadjah Mada, Yogyakarta55281, Indonesia
| | - Tayla Stenta
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Eric Hanssen
- Ian Holmes Imaging Center and Department of Biochemistry and Pharmacology, Bio21 Institute, University of Melbourne, Parkville, VIC 3010, Australia
| | - Katrina M. Bell
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Ritika Saxena
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
| | - Kathryn S. Stok
- Department of Biomedical Engineering, University of Melbourne, Parkville, VIC 3010, Australia
| | - Edouard G. Stanley
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Andrew G. Elefanty
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - John F. Bateman
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia
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23
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Otani S, Ohnuma M, Ito K, Matsushita Y. Cellular dynamics of distinct skeletal cells and the development of osteosarcoma. Front Endocrinol (Lausanne) 2023; 14:1181204. [PMID: 37229448 PMCID: PMC10203529 DOI: 10.3389/fendo.2023.1181204] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 04/21/2023] [Indexed: 05/27/2023] Open
Abstract
Bone contributes to the maintenance of vital biological activities. At the cellular level, multiple types of skeletal cells, including skeletal stem and progenitor cells (SSPCs), osteoblasts, chondrocytes, marrow stromal cells, and adipocytes, orchestrate skeletal events such as development, aging, regeneration, and tumorigenesis. Osteosarcoma (OS) is a primary malignant tumor and the main form of bone cancer. Although it has been proposed that the cellular origins of OS are in osteogenesis-related skeletal lineage cells with cancer suppressor gene mutations, its origins have not yet been fully elucidated because of a poor understanding of whole skeletal cell diversity and dynamics. Over the past decade, the advent and development of single-cell RNA sequencing analyses and mouse lineage-tracing approaches have revealed the diversity of skeletal stem and its lineage cells. Skeletal stem cells (SSCs) in the bone marrow endoskeletal region have now been found to efficiently generate OS and to be robust cells of origin under p53 deletion conditions. The identification of SSCs may lead to a more limited redefinition of bone marrow mesenchymal stem/stromal cells (BM-MSCs), and this population has been thought to contain cells from which OS originates. In this mini-review, we discuss the cellular diversity and dynamics of multiple skeletal cell types and the origin of OS in the native in vivo environment in mice. We also discuss future challenges in the study of skeletal cells and OS.
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Affiliation(s)
- Shohei Otani
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Mizuho Ohnuma
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
- Department of Clinical Oral Oncology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Kosei Ito
- Department of Molecular Bone Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Yuki Matsushita
- Department of Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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24
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Marcucio R, Miclau T, Bahney C. A Shifting Paradigm: Transformation of Cartilage to Bone during Bone Repair. J Dent Res 2023; 102:13-20. [PMID: 36303415 PMCID: PMC9791286 DOI: 10.1177/00220345221125401] [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] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
While formation and regeneration of the skeleton have been studied for a long period of time, significant scientific advances in this field continue to emerge based on an unmet clinical need to improve options to promote bone repair. In this review, we discuss the relationship between mechanisms of bone formation and bone regeneration. Data clearly show that regeneration is not simply a reinduction of the molecular and cellular programs that were used for development. Instead, the mechanical environment exerts a strong influence on the mode of repair, while during development, cell-intrinsic processes drive the mode of skeletal formation. A major advance in the field has shown that cell fate is flexible, rather than terminal, and that chondrocytes are able to differentiate into osteoblasts and other cell types during development and regeneration. This is discussed in a larger context of regeneration in vertebrates as well as the clinical implication that this shift in understanding presents.
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Affiliation(s)
- R.S. Marcucio
- University of California, San Francisco (UCSF), Orthopaedic Trauma Institute, San Francisco, CA, USA
| | - T. Miclau
- University of California, San Francisco (UCSF), Orthopaedic Trauma Institute, San Francisco, CA, USA
| | - C.S. Bahney
- University of California, San Francisco (UCSF), Orthopaedic Trauma Institute, San Francisco, CA, USA
- Steadman Philippon Research Institute, Vail, CO, USA
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25
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The role of hypertrophic chondrocytes in regulation of the cartilage-to-bone transition in fracture healing. Bone Rep 2022; 17:101616. [PMID: 36105852 PMCID: PMC9465425 DOI: 10.1016/j.bonr.2022.101616] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/05/2022] [Accepted: 06/07/2022] [Indexed: 11/23/2022] Open
Abstract
Endochondral bone formation is an important pathway in fracture healing, involving the formation of a cartilaginous soft callus and the process of cartilage-to-bone transition. Failure or delay in the cartilage-to-bone transition causes an impaired bony union such as nonunion or delayed union. During the healing process, multiple types of cells including chondrocytes, osteoprogenitors, osteoblasts, and endothelial cells coexist in the callus, and inevitably crosstalk with each other. Hypertrophic chondrocytes located between soft cartilaginous callus and bony hard callus mediate the crosstalk regulating cell-matrix degradation, vascularization, osteoclast recruitment, and osteoblast differentiation in autocrine and paracrine manners. Furthermore, hypertrophic chondrocytes can become osteoprogenitors and osteoblasts, and directly contribute to woven bone formation. In this review, we focus on the roles of hypertrophic chondrocytes in fracture healing and dissect the intermingled crosstalk in fracture callus during the cartilage-to-bone transition.
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26
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Abstract
The tissue-resident skeletal stem cells (SSCs), which are self-renewal and multipotent, continuously provide cells (including chondrocytes, bone cells, marrow adipocytes, and stromal cells) for the development and homeostasis of the skeletal system. In recent decade, utilizing fluorescence-activated cell sorting, lineage tracing, and single-cell sequencing, studies have identified various types of SSCs, plotted the lineage commitment trajectory, and partially revealed their properties under physiological and pathological conditions. In this review, we retrospect to SSCs identification and functional studies. We discuss the principles and approaches to identify bona fide SSCs, highlighting pioneering findings that plot the lineage atlas of SSCs. The roles of SSCs and progenitors in long bone, craniofacial tissues, and periosteum are systematically discussed. We further focus on disputes and challenges in SSC research.
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27
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Xiu C, Gong T, Luo N, Ma L, Zhang L, Chen J. Suppressor of fused-restrained Hedgehog signaling in chondrocytes is critical for epiphyseal growth plate maintenance and limb elongation in juvenile mice. Front Cell Dev Biol 2022; 10:997838. [PMID: 36120578 PMCID: PMC9479194 DOI: 10.3389/fcell.2022.997838] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/12/2022] [Indexed: 11/21/2022] Open
Abstract
Hedgehog (Hh) signaling plays multiple critical roles in regulating chondrocyte proliferation and differentiation during epiphyseal cartilage development. However, it is still unclear whether Hh signaling in chondrocytes is required for growth plate maintenance during juvenile growth, and whether sustained activation of Hh signaling in chondrocytes promotes limb elongation. In this study, we first utilized Hh reporter mice to reveal that Hh signaling was activated in resting and columnar chondrocytes in growth plates of juvenile and adult mice. Next, we genetically modulated Hh signaling by conditionally deleting Smo or Sufu in all or a subpopulation of growth plate chondrocytes, and found that ablation of either Smo or Sufu in chondrocytes of juvenile mice caused premature closure of growth plates and shorter limbs, whereas Osx-Cre-mediated deletion of either of these two genes in prehypertrophic chondrocytes did not lead to obvious growth plate defects, indicating that Hh signaling mainly functions in resting and/or columnar chondrocytes to maintain growth plates at the juvenile stage. At the cellular level, we found that chondrocyte-specific ablation of Smo or Sufu accelerated or suppressed chondrocyte hypertrophy, respectively, whereas both decreased chondrocyte proliferation and survival. Thus, our study provided the first genetic evidence to establish the essential cell-autonomous roles for tightly-regulated Hh signaling in epiphyseal growth plate maintenance and limb elongation during juvenile growth.
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Affiliation(s)
- Chunmei Xiu
- Orthopedic Institute, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Tingting Gong
- Orthopedic Institute, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Na Luo
- Orthopedic Institute, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Linghui Ma
- Orthopedic Institute, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
| | - Lei Zhang
- Orthopedic Institute, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- *Correspondence: Jianquan Chen, ; Lei Zhang,
| | - Jianquan Chen
- Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province, Department of Clinical Medicine, School of Medicine, Zhejiang University City College, Hangzhou, Zhejiang, China
- Department of Orthopaedics, First Affiliated Hospital of Soochow University, Orthopedic Institute, Suzhou Medical College of Soochow University, Suzhou, Jiangsu, China
- *Correspondence: Jianquan Chen, ; Lei Zhang,
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28
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Bell N, Bhagat S, Muruganandan S, Kim R, Ho K, Pierce R, Kozhemyakina E, Lassar AB, Gamer L, Rosen V, Ionescu AM. Overexpression of transcription factor FoxA2 in the developing skeleton causes an enlargement of the cartilage hypertrophic zone, but it does not trigger ectopic differentiation in immature chondrocytes. Bone 2022; 160:116418. [PMID: 35398294 PMCID: PMC9133231 DOI: 10.1016/j.bone.2022.116418] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 01/29/2023]
Abstract
We previously found that FoxA factors are necessary for chondrocyte differentiation. To investigate whether FoxA factors alone are sufficient to drive chondrocyte hypertrophy, we build a FoxA2 transgenic mouse in which FoxA2 cDNA is driven by a reiterated Tetracycline Response Element (TRE) and a minimal CMV promoter. This transgenic line was crossed with a col2CRE;Rosa26rtTA/+ mouse line to generate col2CRE;Rosa26rtTA/+;TgFoxA2+/- mice for inducible expression of FoxA2 in cartilage using doxycycline treatment. Ectopic expression of FoxA2 in the developing skeleton reveals skeletal defects and shorter skeletal elements in E17.5 mice. The chondro-osseous border was frequently mis-shaped in mutant mice, with small islands of col.10+ hypertrophic cells extending in the metaphyseal bone. Even though overexpression of FoxA2 causes an accumulation of hypertrophic chondrocytes, it did not trigger ectopic hypertrophy in the immature chondrocytes. This suggests that FoxA2 may need transcriptional co-factors (such as Runx2), whose expression is restricted to the hypertrophic zone, and absent in the immature chondrocytes. To investigate a potential FoxA2/Runx2 interaction in immature chondrocytes versus hypertrophic cells, we separated these two subpopulations by FACS to obtain CD24+CD200+ hypertrophic chondrocytes and CD24+CD200- immature chondrocytes and we ectopically expressed FoxA2 alone or in combination with Runx2 via lentiviral gene delivery. In CD24+CD200+ hypertrophic chondrocytes, FoxA2 enhanced the expression of chondrocyte hypertrophic markers collagen 10, MMP13, and alkaline phosphatase. In contrast, in the CD24+CD200- immature chondrocytes, neither FoxA2 nor Runx2 overexpression could induce ectopic expression of hypertrophic markers MMP13, alkaline phosphatase, or PTH/PTHrP receptor. Overall these findings mirror our in vivo data, and suggest that induction of chondrocyte hypertrophy by FoxA2 may require other factors in addition to Runx2 (i.e., Hif2α, MEF2C, or perhaps unknown factors), whose expression/activity is rate-limiting in immature chondrocytes.
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Affiliation(s)
- Nicole Bell
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America
| | - Sanket Bhagat
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America.
| | - Shanmugam Muruganandan
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America; Department of Biology, 134 Mugar Life Sciences Building, Northeastern University, 360 Huntington Ave, Boston, MA 02115, United States of America.
| | - Ryunhyung Kim
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America.
| | - Kailing Ho
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America.
| | - Rachel Pierce
- Department of Biology, 134 Mugar Life Sciences Building, Northeastern University, 360 Huntington Ave, Boston, MA 02115, United States of America.
| | - Elena Kozhemyakina
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave, Boston, MA 02115, United States of America.
| | - Andrew B Lassar
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave, Boston, MA 02115, United States of America.
| | - Laura Gamer
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America.
| | - Vicki Rosen
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America.
| | - Andreia M Ionescu
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, United States of America; Department of Biology, 134 Mugar Life Sciences Building, Northeastern University, 360 Huntington Ave, Boston, MA 02115, United States of America.
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29
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Georgieva VS, Bluhm B, Probst K, Zhu M, Heilig J, Niehoff A, Brachvogel B. Ablation of the miRNA cluster 24 in cartilage and osteoblasts impairs bone remodeling. Sci Rep 2022; 12:9116. [PMID: 35650319 PMCID: PMC9160244 DOI: 10.1038/s41598-022-13231-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/13/2022] [Indexed: 11/28/2022] Open
Abstract
MicroRNAs (miRNAs) post-transcriptionally regulate cartilage and bone development and function, however, only few miRNAs have been described to play a role for cartilage to bone transition in vivo. Previously, we showed that cartilage-specific deletion of the Mirc24 cluster in newborn male mice leads to impaired growth plate cartilage development due to increased RAF/MEK/ERK signaling and affects the stability of the cartilage extracellular matrix on account of decreased SOX6 and SOX9 and increased MMP13 levels. Here, we studied how Mirc24 cluster inactivation in cartilage and osteoblasts leads to an increased bone density associated with defects in collagen remodeling in trabecular bone. No changes in osteoblast distribution were observed, whereas the number of osteoclasts was reduced and TRAP activity in osteoclasts decreased. Surprisingly, an increased level of cluster-encoded miR-322 or miR-503 raises Rankl gene expression and inactivation of the cluster in chondrocytes reduces Rankl expression. These results suggest that the Mirc24 cluster regulates Rankl expression in chondrocytes at the chondro-osseous border, where the cluster is mainly expressed to modulate osteoclast formation, bone remodeling and bone integrity.
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Affiliation(s)
- Veronika S Georgieva
- Center for Biochemistry, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany
| | - Björn Bluhm
- Center for Biochemistry, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany
| | - Kristina Probst
- Center for Biochemistry, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany
| | - Mengjie Zhu
- Center for Biochemistry, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany.,Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany
| | - Juliane Heilig
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, 50933, Cologne, Germany.,Cologne Center for Musculoskeletal Biomechanics (CCMB), University of Cologne, 50931, Cologne, Germany
| | - Anja Niehoff
- Institute of Biomechanics and Orthopaedics, German Sport University Cologne, 50933, Cologne, Germany.,Cologne Center for Musculoskeletal Biomechanics (CCMB), University of Cologne, 50931, Cologne, Germany
| | - Bent Brachvogel
- Center for Biochemistry, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany. .,Department of Pediatrics and Adolescent Medicine, Experimental Neonatology, Faculty of Medicine, University of Cologne, 50931, Cologne, Germany.
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Identification of distinct non-myogenic skeletal-muscle-resident mesenchymal cell populations. Cell Rep 2022; 39:110785. [PMID: 35545045 PMCID: PMC9535675 DOI: 10.1016/j.celrep.2022.110785] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/23/2022] [Accepted: 04/13/2022] [Indexed: 12/13/2022] Open
Abstract
Mesenchymal progenitors of the lateral plate mesoderm give rise to various cell fates within limbs, including a heterogeneous group of muscle-resident mesenchymal cells. Often described as fibro-adipogenic progenitors, these cells are key players in muscle development, disease, and regeneration. To further define this cell population(s), we perform lineage/reporter analysis, flow cytometry, single-cell RNA sequencing, immunofluorescent staining, and differentiation assays on normal and injured murine muscles. Here we identify six distinct Pdgfra+ non-myogenic muscle-resident mesenchymal cell populations that fit within a bipartite differentiation trajectory from a common progenitor. One branch of the trajectory gives rise to two populations of immune-responsive mesenchymal cells with strong adipogenic potential and the capability to respond to acute and chronic muscle injury, whereas the alternative branch contains two cell populations with limited adipogenic capacity and inherent mineralizing capabilities; one of the populations displays a unique neuromuscular junction association and an ability to respond to nerve injury. Leinroth et al. explore the heterogeneity of Pdgfra+ muscle-resident mesenchymal cells, demonstrating that Pdgfra+ subpopulations have unique gene expression profiles, exhibit two distinct cell trajectories from a common progenitor, differ in their abilities to respond to muscle injuries, and show variable adipogenic and mineralizing capacities.
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