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Pastor FM, de Melo Ocarino N, Silva JF, Reis AMS, Serakides R. Bone development in fetuses with intrauterine growth restriction caused by maternal endocrine-metabolic dysfunctions. Bone 2024; 186:117169. [PMID: 38880170 DOI: 10.1016/j.bone.2024.117169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/21/2024] [Accepted: 06/13/2024] [Indexed: 06/18/2024]
Abstract
Intrauterine growth restriction (IUGR) affects a large proportion of infants, particularly in underdeveloped countries. Among the main causes of IUGR, maternal endocrine-metabolic dysfunction is highlighted, either due to its high incidence or due to the severity of the immediate and mediated changes that these dysfunctions cause in the fetus and the mother. Although the effects of endocrine and metabolic disorders have been widely researched, there are still no reviews that bring together and summarize the effects of these conditions on bone development in cases of IUGR. Therefore, the present literature review was conducted with the aim of discussing bone changes observed in fetuses with IUGR caused by maternal endocrine-metabolic dysfunction. The main endocrine dysfunctions that occur with IUGR include maternal hyperthyroidism, hypothyroidism, and hypoparathyroidism. Diabetes mellitus, hypertensive disorders, and obesity are the most important maternal metabolic dysfunctions that compromise fetal growth. The bone changes reported in the fetus are, for the most part, due to damage to cell proliferation and differentiation, as well as failures in the synthesis and mineralization of the extracellular matrix, which results in shortening and fragility of the bones. Some maternal dysfunctions, such as hyperthyroidism, have been widely studied, whereas conditions such as hypoparathyroidism and gestational hypertensive disorders require further study regarding the mechanisms underlying the development of bone changes. Similarly, there is a gap in the literature regarding changes related to intramembranous ossification, as most published articles only describe changes in endochondral bone formation associated with IUGR. Furthermore, there is a need for more research aimed at elucidating the late postnatal changes that occur in the skeletons of individuals affected by IUGR and their possible relationships with adult diseases, such as osteoarthritis and osteoporosis.
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Affiliation(s)
- Felipe Martins Pastor
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Natália de Melo Ocarino
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Juneo Freitas Silva
- Centro de Microscopia Eletrônica, Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Jorge Amado, Km 16, 45662-900 Ilhéus, Bahia, Brazil
| | - Amanda Maria Sena Reis
- Departamento de Patologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil
| | - Rogéria Serakides
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil.
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2
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Pastor FM, Amaral CI, de Melo Ocarino N, Dias LA, da Silveira Xavier AB, Castelo Branco EC, Serakides R. Thyroid dysgenesis associated with dwarfism, osteoporosis and spontaneous fractures in a goat. J Comp Pathol 2024; 213:20-27. [PMID: 39029283 DOI: 10.1016/j.jcpa.2024.06.005] [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: 04/25/2024] [Revised: 05/27/2024] [Accepted: 06/15/2024] [Indexed: 07/21/2024]
Abstract
An 11-month-old female Saanen goat, weighing 12.7 kg, was taken to the Veterinary Hospital of the Federal University of Minas Gerais because of sternal recumbency. On clinical examination, the animal was much smaller than expected and had hair similar to that of puppies and areas of hyperpigmentation on the head and dorsocervical and dorsothoracic cranial regions. Radiographic examination revealed fractures in both femurs and severe generalized osteoporosis. Given the unfavourable prognosis, the animal was euthanized. Necropsy revealed generalized pallor, muscular atrophy of the pelvic limbs and little reserve of subcutaneous adipose tissue. Both femurs had complete and closed diaphyseal fractures. The second lumbar vertebra was severely reduced in length as a result of a fracture, with dorsal displacement of the vertebral body towards the vertebral canal and compression of the spinal cord. Long bones and vertebrae had severe cortical thinning, enlargement of the medullary canal and reduced resistance. The thyroid gland was not in its normal anatomical location. A pale red nodule (1.0 × 0.4 cm) in the serosa of the middle third of the trachea, close to the thoracic entrance, was confirmed as ectopic thyroid tissue. Microscopically, the bones had evidence of growth arrest and severe osteoporosis. The ectopic thyroid nodule was hyperplastic with severe hypertrophy of follicular cells. The spinal cord was compressed by vertebral fractures and had focally extensive and severe myelomalacia. Based on the pathological features, the case was diagnosed as thyroid dysgenesis characterized by eutopic thyroid agenesis and ectopic thyroid tissue, associated with interruption of bone growth with dwarfism, osteoporosis and spontaneous secondary fractures with compression of the lumbar spinal cord.
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Affiliation(s)
- Felipe M Pastor
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Camila I Amaral
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Natália de Melo Ocarino
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Lucas A Dias
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Andressa B da Silveira Xavier
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Eloá C Castelo Branco
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil
| | - Rogéria Serakides
- Departamento de Cínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901, Belo Horizonte, Minas Gerais, Brazil.
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3
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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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Rundle CH, Gomez GA, Pourteymoor S, Mohan S. Sequential application of small molecule therapy enhances chondrogenesis and angiogenesis in murine segmental defect bone repair. J Orthop Res 2023; 41:1471-1481. [PMID: 36448182 PMCID: PMC10506518 DOI: 10.1002/jor.25493] [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: 04/06/2022] [Revised: 10/03/2022] [Accepted: 11/28/2022] [Indexed: 12/05/2022]
Abstract
The increasing incidence of physiologic/pathologic conditions that impair the otherwise routine healing of endochondral bone fractures and the occurrence of severe bone injuries necessitate novel approaches to enhance clinically challenging bone fracture repair. To promote the healing of nonunion fractures, we tested an approach that used two small molecules to sequentially enhance cartilage development and conversion to the bone in the callus of a murine femoral segmental defect nonunion model of bone injury. Systemic injections of smoothened agonist 21k (SAG21k) were used to stimulate chondrogenesis through the activation of the sonic hedgehog (SHH) pathway early in bone repair, while injections of the prolyl hydroxylase domain (PHD)2 inhibitor, IOX2, were used to stimulate hypoxia signaling-mediated endochondral bone formation. The expression of SHH pathway genes and Phd2 target genes was increased in chondrocyte cell lines in response to SAG21k and IOX2 treatment, respectively. The segmental defect responded to sequential systemic administration of these small molecules with increased chondrocyte expression of PTCH1, GLI1, and SOX9 in response to SAG and increased expression of hypoxia-induced factor-1α and vascular endothelial growth factor-A in the defect tissues in response to IOX2. At 6 weeks postsurgery, the combined SAG-IOX2 therapy produced increased bone formation in the defect with the bony union over the injury. Clinical significance: This therapeutic approach was successful in promoting cartilage and bone formation within a critical-size segmental defect and established the utility of a sequential small molecule therapy for the enhancement of fracture callus development in clinically challenging bone injuries.
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Affiliation(s)
- Charles H. Rundle
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, California, USA
- Department of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Gustavo A. Gomez
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, California, USA
| | - Sheila Pourteymoor
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, California, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, California, USA
- Department of Medicine, Loma Linda University, Loma Linda, California, USA
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5
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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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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: 8] [Impact Index Per Article: 4.0] [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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Direct Reprogramming of Mouse Subchondral Bone Osteoblasts into Chondrocyte-like Cells. Biomedicines 2022; 10:biomedicines10102582. [PMID: 36289842 PMCID: PMC9599480 DOI: 10.3390/biomedicines10102582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/29/2022] [Accepted: 10/12/2022] [Indexed: 11/16/2022] Open
Abstract
Treatment of full-thickness articular cartilage defects with exposure of subchondral bone often seen in osteoarthritic conditions has long been a great challenge, especially with a focus on the feasibility of in situ cartilage regeneration through minimally invasive procedures. Osteoblasts that situate in the subchondral bone plate may be considered a potentially vital endogenous source of cells for cartilage resurfacing through direct reprogramming into chondrocytes. Microarray-based gene expression profiles were generated to compare tissue-specific transcripts between subchondral bone and cartilage of mice and to assess age-dependent differences of chondrocytes as well. On osteoblast cell lines established from mouse proximal tibial subchondral bone, sequential screening by co-transduction of transcription factor (TF) genes that distinguish chondrocytes from osteoblasts reveals a shortlist of potential reprogramming factors exhibiting combined effects in inducing chondrogenesis of subchondral bone osteoblasts. A further combinatorial approach unexpectedly identified two 3-TF combinations containing Sox9 and Sox5 that exhibit differences in reprogramming propensity with the third TF c-Myc or Plagl1, which appeared to direct the converted chondrocytes toward either a superficial or a deeper zone phenotype. Thus, our approach demonstrates the possibility of converting osteoblasts into two major chondrocyte subpopulations with two combinations of three genes (Sox9, Sox5, and c-Myc or Plagl1). The findings may have important implications for developing novel in situ regeneration strategies for the reconstruction of full-thickness cartilage defects.
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The Emerging Role of Cell Transdifferentiation in Skeletal Development and Diseases. Int J Mol Sci 2022; 23:ijms23115974. [PMID: 35682655 PMCID: PMC9180549 DOI: 10.3390/ijms23115974] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 02/04/2023] Open
Abstract
The vertebrate musculoskeletal system is known to be formed by mesenchymal stem cells condensing into tissue elements, which then differentiate into cartilage, bone, tendon/ligament, and muscle cells. These lineage-committed cells mature into end-stage differentiated cells, like hypertrophic chondrocytes and osteocytes, which are expected to expire and to be replaced by newly differentiated cells arising from the same lineage pathway. However, there is emerging evidence of the role of cell transdifferentiation in bone development and disease. Although the concept of cell transdifferentiation is not new, a breakthrough in cell lineage tracing allowed scientists to trace cell fates in vivo. Using this powerful tool, new theories have been established: (1) hypertrophic chondrocytes can transdifferentiate into bone cells during endochondral bone formation, fracture repair, and some bone diseases, and (2) tendon cells, beyond their conventional role in joint movement, directly participate in normal bone and cartilage formation, and ectopic ossification. The goal of this review is to obtain a better understanding of the key roles of cell transdifferentiation in skeletal development and diseases. We will first review the transdifferentiation of chondrocytes to bone cells during endochondral bone formation. Specifically, we will include the history of the debate on the fate of chondrocytes during bone formation, the key findings obtained in recent years on the critical factors and molecules that regulate this cell fate change, and the role of chondrocyte transdifferentiation in skeletal trauma and diseases. In addition, we will also summarize the latest discoveries on the novel roles of tendon cells and adipocytes on skeletal formation and diseases.
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9
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Gomez GA, Aghajanian P, Pourteymoor S, Larkin D, Mohan S. Differences in pathways contributing to thyroid hormone effects on postnatal cartilage calcification versus secondary ossification center development. eLife 2022; 11:76730. [PMID: 35098920 PMCID: PMC8830887 DOI: 10.7554/elife.76730] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 01/28/2022] [Indexed: 11/17/2022] Open
Abstract
The proximal and distal femur epiphyses of mice are both weight-bearing structures derived from chondrocytes but differ in development. Mineralization at the distal epiphysis occurs in an osteoblast-rich secondary ossification center (SOC), while the chondrocytes of the proximal femur head (FH), in particular, are directly mineralized. Thyroid hormone (TH) plays important roles in distal knee SOC formation, but whether TH also affects proximal FH development remains unexplored. Here, we found that TH controls chondrocyte maturation and mineralization at the FH in vivo through studies in thyroid stimulating hormone receptor (Tshr-/-) hypothyroid mice by X-ray, histology, transcriptional profiling, and immunofluorescence staining. Both in vivo and in vitro studies conducted in ATDC5 chondrocyte progenitors concur that TH regulates expression of genes that modulate mineralization (Ibsp, Bglap2, Dmp1, Spp1, and Alpl). Our work also delineates differences in prominent transcription factor regulation of genes involved in the different mechanisms leading to proximal FH cartilage calcification and endochondral ossification at the distal femur. The information on the molecular pathways contributing to postnatal cartilage calcification can provide insights on therapeutic strategies to treat pathological calcification that occurs in soft tissues such as aorta, kidney, and articular cartilage.
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Affiliation(s)
- Gustavo A Gomez
- Musculoskeletal Disease Centre, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, United States
| | | | - Sheila Pourteymoor
- Musculoskeletal Disease Centre, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, United States
| | - Destiney Larkin
- Musculoskeletal Disease Centre, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, United States
| | - Subburaman Mohan
- Musculoskeletal Disease Centre, Jerry L. Pettis Memorial VA Medical Center, Loma Linda, United States
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10
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Rabea AA. Assessment of bone marrow-derived mesenchymal stem cells capacity for odontogenic differentiation and dentin regeneration in methimazole-treated albino rats (Light microscopic Study). Saudi Dent J 2022; 34:27-35. [PMID: 35068896 PMCID: PMC8767165 DOI: 10.1016/j.sdentj.2021.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 09/05/2021] [Accepted: 09/08/2021] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND Methimazole is an antithyroid drug. It has side effects on many tissues. Bone marrow-derived mesenchymal stem cells (BM-MSCs) are promising in the field of tissue regeneration. OBJECTIVE To investigate the capacity of BM-MSCs on odontogenic differentiation and dentin regeneration at different time intervals in methimazole treated rats. METHODS Twenty-eight male albino rats were classified as: Group I: got distilled water. Group II: obtained therapeutic dosage of methimazole as pro-drug "Neo-Mercazole®". Group III: received methimazole then solitary injection of BM-MSCs at day 21. Group IV: obtained methimazole and single injection of BM-MSCs at the beginning of the experiment. Light microscope was used to examine specimens. Recently formed collagen and β-catenin-immunoreactivity area% were appraised histomorphometrically and statistically. RESULTS Histological examination of odontoblasts and dentin illustrated normal structure in Group I and nearly normal features in Group IV. Group II demonstrated discontinuation of odontoblastic layer and areas of different stainability in dentin. Group III showed an evidently wide layer of odontoblast-like cells and distinct dentinal tubules. Masson's trichrome results of dentin in Groups I &IV showed apparently equal areas of new and old collagen. Group II illustrated old collagen mainly. Group III explored new collagen only. β-catenin-immunoreactivity was strong in Groups I & IV, mild in Group II and moderate in Group III. Statistical results revealed that the highest mean of newly formed collagen area% was in Group III, followed by Group I, Group IV then Group II respectively. Regarding β-catenin-immunoreactivity area%, the highest mean was recorded in Group I, subsequently Group IV, next Group III then Group II. CONCLUSIONS Methimazole has destructive consequences. BM-MSCs have a time-based increased capacity for odontogenic differentiation and regeneration of dentin.
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Affiliation(s)
- Amany A. Rabea
- Associate Professor of Oral Biology, Faculty of Oral and Dental Medicine, Future University in Egypt, Cairo, Egypt
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11
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Phenotypic effect of a single nucleotide polymorphism on SSC7 on fetal outcomes in PRRSV-2 infected gilts. Livest Sci 2022. [DOI: 10.1016/j.livsci.2021.104800] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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12
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Abraham SP, Nita A, Krejci P, Bosakova M. Cilia kinases in skeletal development and homeostasis. Dev Dyn 2021; 251:577-608. [PMID: 34582081 DOI: 10.1002/dvdy.426] [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: 07/07/2021] [Revised: 09/22/2021] [Accepted: 09/22/2021] [Indexed: 11/08/2022] Open
Abstract
Primary cilia are dynamic compartments that regulate multiple aspects of cellular signaling. The production, maintenance, and function of cilia involve more than 1000 genes in mammals, and their mutations disrupt the ciliary signaling which manifests in a plethora of pathological conditions-the ciliopathies. Skeletal ciliopathies are genetic disorders affecting the development and homeostasis of the skeleton, and encompass a broad spectrum of pathologies ranging from isolated polydactyly to lethal syndromic dysplasias. The recent advances in forward genetics allowed for the identification of novel regulators of skeletogenesis, and revealed a growing list of ciliary proteins that are critical for signaling pathways implicated in bone physiology. Among these, a group of protein kinases involved in cilia assembly, maintenance, signaling, and disassembly has emerged. In this review, we summarize the functions of cilia kinases in skeletal development and disease, and discuss the available and upcoming treatment options.
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Affiliation(s)
- Sara P Abraham
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Alexandru Nita
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Pavel Krejci
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.,Institute of Animal Physiology and Genetics of the CAS, Brno, Czech Republic.,International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic
| | - Michaela Bosakova
- Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.,Institute of Animal Physiology and Genetics of the CAS, Brno, Czech Republic.,International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic
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Osteocyte Dysfunction in Joint Homeostasis and Osteoarthritis. Int J Mol Sci 2021; 22:ijms22126522. [PMID: 34204587 PMCID: PMC8233862 DOI: 10.3390/ijms22126522] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/13/2021] [Accepted: 06/16/2021] [Indexed: 01/29/2023] Open
Abstract
Structural disturbances of the subchondral bone are a hallmark of osteoarthritis (OA), including sclerotic changes, cystic lesions, and osteophyte formation. Osteocytes act as mechanosensory units for the micro-cracks in response to mechanical loading. Once stimulated, osteocytes initiate the reparative process by recruiting bone-resorbing cells and bone-forming cells to maintain bone homeostasis. Osteocyte-expressed sclerostin is known as a negative regulator of bone formation through Wnt signaling and the RANKL pathway. In this review, we will summarize current understandings of osteocytes at the crossroad of allometry and mechanobiology to exploit the relationship between osteocyte morphology and function in the context of joint aging and osteoarthritis. We also aimed to summarize the osteocyte dysfunction and its link with structural and functional disturbances of the osteoarthritic subchondral bone at the molecular level. Compared with normal bones, the osteoarthritic subchondral bone is characterized by a higher bone volume fraction, a larger trabecular bone number in the load-bearing region, and an increase in thickness of pre-existing trabeculae. This may relate to the aberrant expressions of sclerostin, periostin, dentin matrix protein 1, matrix extracellular phosphoglycoprotein, insulin-like growth factor 1, and transforming growth factor-beta, among others. The number of osteocyte lacunae embedded in OA bone is also significantly higher, yet the volume of individual lacuna is relatively smaller, which could suggest abnormal metabolism in association with allometry. The remarkably lower percentage of sclerostin-positive osteocytes, together with clustering of Runx-2 positive pre-osteoblasts, may suggest altered regulation of osteoblast differentiation and osteoblast-osteocyte transformation affected by both signaling molecules and the extracellular matrix. Aberrant osteocyte morphology and function, along with anomalies in molecular signaling mechanisms, might explain in part, if not all, the pre-osteoblast clustering and the uncoupled bone remodeling in OA subchondral bone.
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Fernández-Iglesias Á, Fuente R, Gil-Peña H, Alonso-Durán L, Santos F, López JM. The Formation of the Epiphyseal Bone Plate Occurs via Combined Endochondral and Intramembranous-Like Ossification. Int J Mol Sci 2021; 22:ijms22020900. [PMID: 33477458 PMCID: PMC7830543 DOI: 10.3390/ijms22020900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/08/2021] [Accepted: 01/15/2021] [Indexed: 11/24/2022] Open
Abstract
The formation of the epiphyseal bone plate, the flat bony structure that provides strength and firmness to the growth plate cartilage, was studied in the present study by using light, confocal, and scanning electron microscopy. Results obtained evidenced that this bone tissue is generated by the replacement of the lower portion of the epiphyseal cartilage. However, this process differs considerably from the usual bone tissue formation through endochondral ossification. Osteoblasts deposit bone matrix on remnants of mineralized cartilage matrix that serve as a scaffold, but also on non-mineralized cartilage surfaces and as well as within the perivascular space. These processes occur simultaneously at sites located close to each other, so that, a core of the sheet of bone is established very quickly. Subsequently, thickening and reshaping occurs by appositional growth to generate a dense parallel-fibered bone structurally intermediate between woven and lamellar bone. All these processes occur in close relationship with a cartilage but most of the bone tissue is generated in a manner that may be considered as intramembranous-like. Overall, the findings here reported provide for the first time an accurate description of the tissues and events involved in the formation of the epiphyseal bone plate and gives insight into the complex cellular events underlying bone formation at different sites on the skeleton.
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Affiliation(s)
- Ángela Fernández-Iglesias
- Division of Pediatrics, Department of Medicine, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain; (Á.F.-I.); (R.F.); (H.G.-P.); (L.A.-D.); (F.S.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Asturias, Spain
| | - Rocío Fuente
- Division of Pediatrics, Department of Medicine, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain; (Á.F.-I.); (R.F.); (H.G.-P.); (L.A.-D.); (F.S.)
| | - Helena Gil-Peña
- Division of Pediatrics, Department of Medicine, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain; (Á.F.-I.); (R.F.); (H.G.-P.); (L.A.-D.); (F.S.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Asturias, Spain
- Department of Pediatrics, Hospital Universitario Central de Asturias (HUCA), 33011 Oviedo, Asturias, Spain
| | - Laura Alonso-Durán
- Division of Pediatrics, Department of Medicine, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain; (Á.F.-I.); (R.F.); (H.G.-P.); (L.A.-D.); (F.S.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Asturias, Spain
| | - Fernando Santos
- Division of Pediatrics, Department of Medicine, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain; (Á.F.-I.); (R.F.); (H.G.-P.); (L.A.-D.); (F.S.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Asturias, Spain
- Department of Pediatrics, Hospital Universitario Central de Asturias (HUCA), 33011 Oviedo, Asturias, Spain
| | - José Manuel López
- Division of Pediatrics, Department of Medicine, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain; (Á.F.-I.); (R.F.); (H.G.-P.); (L.A.-D.); (F.S.)
- Department of Morphology and Cellular Biology, Faculty of Medicine, University of Oviedo, 33006 Oviedo, Asturias, Spain
- Correspondence:
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15
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Dixit M, Poudel SB, Yakar S. Effects of GH/IGF axis on bone and cartilage. Mol Cell Endocrinol 2021; 519:111052. [PMID: 33068640 PMCID: PMC7736189 DOI: 10.1016/j.mce.2020.111052] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 09/29/2020] [Accepted: 10/01/2020] [Indexed: 12/11/2022]
Abstract
Growth hormone (GH) and its mediator, the insulin-like growth factor-1 (IGF-1) regulate somatic growth, metabolism and many aspects of aging. As such, actions of GH/IGF have been studied in many tissues and organs over decades. GH and IGF-1 are part of the hypothalamic/pituitary somatotrophic axis that consists of many other regulatory hormones, receptors, binding proteins, and proteases. In humans, GH/IGF actions peak during pubertal growth and regulate skeletal acquisition through stimulation of extracellular matrix production and increases in bone mineral density. During aging the activity of these hormones declines, a state called somatopaguss, which associates with deleterious effects on the musculoskeletal system. In this review, we will focus on GH/IGF-1 action in bone and cartilage. We will cover many studies that have utilized congenital ablation or overexpression of members of this axis, as well as cell-specific gene-targeting approaches used to unravel the nature of the GH/IGF-1 actions in the skeleton in vivo.
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Affiliation(s)
- Manisha Dixit
- David B. Kriser Dental Center, Department of Molecular Pathobiology, New York University College of Dentistry, NY, 10010, USA
| | - Sher Bahadur Poudel
- David B. Kriser Dental Center, Department of Molecular Pathobiology, New York University College of Dentistry, NY, 10010, USA
| | - Shoshana Yakar
- David B. Kriser Dental Center, Department of Molecular Pathobiology, New York University College of Dentistry, NY, 10010, USA.
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16
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Zhou Y, Yang D, Yang Q, Lv X, Huang W, Zhou Z, Wang Y, Zhang Z, Yuan T, Ding X, Tang L, Zhang J, Yin J, Huang Y, Yu W, Wang Y, Zhou C, Su Y, He A, Sun Y, Shen Z, Qian B, Meng W, Fei J, Yao Y, Pan X, Chen P, Hu H. Single-cell RNA landscape of intratumoral heterogeneity and immunosuppressive microenvironment in advanced osteosarcoma. Nat Commun 2020; 11:6322. [PMID: 33303760 PMCID: PMC7730477 DOI: 10.1038/s41467-020-20059-6] [Citation(s) in RCA: 259] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 11/06/2020] [Indexed: 02/07/2023] Open
Abstract
Osteosarcoma is the most frequent primary bone tumor with poor prognosis. Through RNA-sequencing of 100,987 individual cells from 7 primary, 2 recurrent, and 2 lung metastatic osteosarcoma lesions, 11 major cell clusters are identified based on unbiased clustering of gene expression profiles and canonical markers. The transcriptomic properties, regulators and dynamics of osteosarcoma malignant cells together with their tumor microenvironment particularly stromal and immune cells are characterized. The transdifferentiation of malignant osteoblastic cells from malignant chondroblastic cells is revealed by analyses of inferred copy-number variation and trajectory. A proinflammatory FABP4+ macrophages infiltration is noticed in lung metastatic osteosarcoma lesions. Lower osteoclasts infiltration is observed in chondroblastic, recurrent and lung metastatic osteosarcoma lesions compared to primary osteoblastic osteosarcoma lesions. Importantly, TIGIT blockade enhances the cytotoxicity effects of the primary CD3+ T cells with high proportion of TIGIT+ cells against osteosarcoma. These results present a single-cell atlas, explore intratumor heterogeneity, and provide potential therapeutic targets for osteosarcoma.
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Affiliation(s)
- Yan Zhou
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Dong Yang
- Orthopaedic Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Qingcheng Yang
- Orthopaedic Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Xiaobin Lv
- Central Laboratory of the First Hospital of Nanchang, Nanchang, 330008, China
| | - Wentao Huang
- Pathology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Zhenhua Zhou
- Department of Orthopedic Oncology, Changzheng Hospital of Naval Military Medical University, Shanghai, 200003, China
| | - Yaling Wang
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Zhichang Zhang
- Orthopaedic Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Ting Yuan
- Orthopaedic Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Xiaomin Ding
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Lina Tang
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Jianjun Zhang
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Junyi Yin
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Yujing Huang
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Wenxi Yu
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Yonggang Wang
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Chenliang Zhou
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Yang Su
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Aina He
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Yuanjue Sun
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Zan Shen
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China
| | - Binzhi Qian
- MRC Centre for Reproductive Health & Edinburgh Cancer Research UK Centre, Queen's Medical Research Institute, EH16 4TJ, Edinburgh, United Kingdom
| | - Wei Meng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China
- Guangdong Provincial Key Laboratory of Single Cell Technology and Application, Guangzhou, 510515, China
| | - Jia Fei
- Department of Biochemistry and Molecular Biology, Medical College of Jinan University, 601 Western Huangpu Avenue, Guangzhou, 510632, China
| | - Yang Yao
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China.
| | - Xinghua Pan
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, 510515, China.
- Guangdong Provincial Key Laboratory of Single Cell Technology and Application, Guangzhou, 510515, China.
| | - Peizhan Chen
- Clinical Research Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 201821, China.
| | - Haiyan Hu
- Oncology Department of Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China.
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17
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Schlesinger PH, Braddock DT, Larrouture QC, Ray EC, Riazanski V, Nelson DJ, Tourkova IL, Blair HC. Phylogeny and chemistry of biological mineral transport. Bone 2020; 141:115621. [PMID: 32858255 PMCID: PMC7771281 DOI: 10.1016/j.bone.2020.115621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/24/2020] [Accepted: 08/24/2020] [Indexed: 02/08/2023]
Abstract
Three physiologically mineralizing tissues - teeth, cartilage and bone - have critical common elements and important evolutionary relationships. Phylogenetically the most ancient densely mineralized tissue is teeth. In jawless fishes without skeletons, tooth formation included epithelial transport of phosphates, a process echoed later in bone physiology. Cartilage and mineralized cartilage are skeletal elements separate from bone, but with metabolic features common to bone. Cartilage mineralization is coordinated with high expression of tissue nonspecific alkaline phosphatase and PHOSPHO1 to harvest available phosphate esters and support mineralization of collagen secreted locally. Mineralization in true bone results from stochastic nucleation of hydroxyapatite crystals within the cross-linked collagen fibrils. Mineral accumulation in dense collagen is, at least in major part, mediated by amorphous aggregates - often called Posner clusters - of calcium and phosphate that are small enough to diffuse into collagen fibrils. Mineral accumulation in membrane vesicles is widely suggested, but does not correlate with a definitive stage of mineralization. Conversely mineral deposition at non-physiologic sites where calcium and phosphate are adequate has been shown to be regulated in large part by pyrophosphate. All of these elements are present in vertebrate bone metabolism. A key biological element of bone formation is an epithelial-like cellular organization which allows control of phosphate, calcium and pH during mineralization.
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Affiliation(s)
- Paul H Schlesinger
- Dept of Cell Biology, Washington University, Saint Louis, MO, United States of America
| | - Demetrios T Braddock
- Dept. of Pathology, Yale New Haven Hospital, 310 Cedar Street, New Haven, CT, United States of America
| | - Quitterie C Larrouture
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, Windmill Road, Oxford OX3 7LD, UK
| | - Evan C Ray
- Renal Electrolyte Division, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Vladimir Riazanski
- Dept of Neurobiology, Pharmacology & Physiology, University of Chicago, Chicago, IL, United States of America
| | - Deborah J Nelson
- Dept of Neurobiology, Pharmacology & Physiology, University of Chicago, Chicago, IL, United States of America
| | - Irina L Tourkova
- Veteran's Affairs Medical Center, Pittsburgh PA and Department of Pathology, University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Harry C Blair
- Veteran's Affairs Medical Center, Pittsburgh PA and Department of Pathology, University of Pittsburgh, Pittsburgh, PA, United States of America.
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18
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Jing Y, Wang Z, Li H, Ma C, Feng J. Chondrogenesis Defines Future Skeletal Patterns Via Cell Transdifferentiation from Chondrocytes to Bone Cells. Curr Osteoporos Rep 2020; 18:199-209. [PMID: 32219639 PMCID: PMC7717675 DOI: 10.1007/s11914-020-00586-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE OF REVIEW The goal of this review is to obtain a better understanding of how chondrogenesis defines skeletal development via cell transdifferentiation from chondrocytes to bone cells. RECENT FINDINGS A breakthrough in cell lineage tracing allows bone biologists to trace the cell fate and demonstrate that hypertrophic chondrocytes can directly transdifferentiate into bone cells during endochondral bone formation. However, there is a knowledge gap for the biological significance of this lineage extension and the mechanisms controlling this process. This review first introduces the history of the debate on the cell fate of chondrocytes in endochondral bone formation; then summarizes key findings obtained in recent years, which strongly support a new theory: the direct cell transdifferentiation from chondrocytes to bone cells precisely connects chondrogenesis (for providing a template of the future skeleton, classified as phase I) and osteogenesis (for finishing skeletal construction, or phase II) in a continuous lineage-linked process of endochondral bone formation and limb elongation; and finally outlines nutrition factors and molecules that regulate the cell transdifferentiation process during the relay from chondrogenesis to osteogenesis.
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Affiliation(s)
- Yan Jing
- Department of Orthodontics, Texas A&M University College of Dentistry, 3302 Gaston ave, Dallas, TX, 75246, USA.
| | - Zheng Wang
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA
| | - Hui Li
- Department of Biomedical Sciences, Texas A&M University College of Dentistry, Dallas, TX, USA
- State Key Laboratory of Oral Diseases, Department of Traumatic and Plastic Surgery, , West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Chi Ma
- Department of Research, Texas Scottish Rite Hospital for Children, Dallas, TX, USA
| | - Jian Feng
- Department of Orthodontics, Texas A&M University College of Dentistry, 3302 Gaston ave, Dallas, TX, 75246, USA.
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19
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Kagan BJ, Rosello‐Diez A. Integrating levels of bone growth control: From stem cells to body proportions. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2020; 10:e384. [DOI: 10.1002/wdev.384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 02/09/2020] [Accepted: 04/16/2020] [Indexed: 12/23/2022]
Affiliation(s)
- Brett J. Kagan
- Australian Regenerative Medicine Institute Monash University Clayton Australia
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20
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Leitch VD, Bassett JHD, Williams GR. Role of thyroid hormones in craniofacial development. Nat Rev Endocrinol 2020; 16:147-164. [PMID: 31974498 DOI: 10.1038/s41574-019-0304-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/21/2019] [Indexed: 02/07/2023]
Abstract
The development of the craniofacial skeleton relies on complex temporospatial organization of diverse cell types by key signalling molecules. Even minor disruptions to these processes can result in deleterious consequences for the structure and function of the skull. Thyroid hormone deficiency causes delayed craniofacial and tooth development, dysplastic facial features and delayed development of the ossicles in the middle ear. Thyroid hormone excess, by contrast, accelerates development of the skull and, in severe cases, might lead to craniosynostosis with neurological sequelae and facial hypoplasia. The pathogenesis of these important abnormalities remains poorly understood and underinvestigated. The orchestration of craniofacial development and regulation of suture and synchondrosis growth is dependent on several critical signalling pathways. The underlying mechanisms by which these key pathways regulate craniofacial growth and maturation are largely unclear, but studies of single-gene disorders resulting in craniofacial malformations have identified a number of critical signalling molecules and receptors. The craniofacial consequences resulting from gain-of-function and loss-of-function mutations affecting insulin-like growth factor 1, fibroblast growth factor receptor and WNT signalling are similar to the effects of altered thyroid status and mutations affecting thyroid hormone action, suggesting that these critical pathways interact in the regulation of craniofacial development.
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Affiliation(s)
- Victoria D Leitch
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK
- Royal Melbourne Institute of Technology (RMIT) Centre for Additive Manufacturing, RMIT University, Melbourne, VIC, Australia
| | - J H Duncan Bassett
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| | - Graham R Williams
- Molecular Endocrinology Laboratory, Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
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21
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Tsang KY, Cheah KS. The extended chondrocyte lineage: implications for skeletal homeostasis and disorders. Curr Opin Cell Biol 2019; 61:132-140. [PMID: 31541943 DOI: 10.1016/j.ceb.2019.07.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/19/2019] [Accepted: 07/30/2019] [Indexed: 01/14/2023]
Abstract
Endochondral bone formation relies on a finely controlled sequence of chondrocyte proliferation, maturation and hypertrophy that establishes the growth plate which, combined with the deposition of bone upon the cartilage template, mediates longitudinal skeletal growth. Recent lineage studies support a chondrocyte-osteoblast differentiation continuum and the presence of skeletal stem cells within cartilage. The biological significance of the lineage extension and the mechanisms controlling the process are unclear. In this review, we describe recent work on the extended chondrocyte-osteoblast lineage and its contribution to the development, growth and repair of bone and to bone disorders that provides insight into the process and the molecular controls involved. The implications for skeletal homeostasis are discussed.
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Affiliation(s)
- Kwok Yeung Tsang
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China
| | - Kathryn Se Cheah
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China.
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22
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Lindsey RC, Godwin C, Mohan S. Skeletal effects of nongenomic thyroid hormone receptor beta signaling. J Endocrinol 2019; 242:173-183. [PMID: 31252404 PMCID: PMC6685746 DOI: 10.1530/joe-19-0172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 06/28/2019] [Indexed: 12/25/2022]
Abstract
Thyroid hormone (TH) levels increase rapidly during the prepubertal growth period in mice, and this change is necessary for endochondral ossification of the epiphyses. This effect of TH on epiphyseal chondrocyte hypertrophy is mediated via TRβ1. In addition to its traditional genomic signaling role as a transcription factor, TRβ1 can also exert nongenomic effects by interacting with other signaling molecules such as PI3K. To investigate the role of nongenomic TRβ1 signaling in endochondral ossification, we evaluated the skeletal phenotype of TRβ147F mutant mice which exhibit a normal genomic response of TRβ1 to TH, but the nongenomic response through the PI3K pathway is impaired. Using microCT, we found that 13-week-old TRβ147F mice had significantly less trabecular bone mass at three sites. Histomorphometric analyses revealed that mineralizing surface to bone surface and BFR/BS were reduced in the mutant mice. Mechanistically, we found that activation of TRβ increased Alp and Osx expression in control but not TRβ147F osteoblasts. Since canonical β-catenin signaling has been implicated in mediating nongenomic TRβ-PI3K signaling, we evaluated the effect of TRβ1 activation on β-catenin target gene expression in MC3T3-E1 pre-osteoblasts. We found that β-catenin target genes were increased, suggesting that nongenomic TRβ1-PI3K pathway modulation of β-catenin signaling may mediate TRβ1 effects on osteoblast differentiation. Together, these results suggest that TH acting through TRβ1 regulates endochondral ossification in part via nongenomic signaling in mice. Further investigation of this nongenomic mechanism of TRβ1 signaling could lead to novel therapeutic targets for treatment and prevention of osteoporosis.
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Affiliation(s)
- Richard C. Lindsey
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
- Center for Health Disparities and Molecular Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Division of Biochemistry, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Catrina Godwin
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA, USA
- Center for Health Disparities and Molecular Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Division of Biochemistry, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Department of Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
- Department of Orthopedics, School of Medicine, Loma Linda University, Loma Linda, CA, USA
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23
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Xing W, Godwin C, Pourteymoor S, Mohan S. Conditional disruption of the osterix gene in chondrocytes during early postnatal growth impairs secondary ossification in the mouse tibial epiphysis. Bone Res 2019; 7:24. [PMID: 31646014 PMCID: PMC6804621 DOI: 10.1038/s41413-019-0064-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 06/04/2019] [Accepted: 06/19/2019] [Indexed: 12/12/2022] Open
Abstract
In our previous studies, we have found that the prepubertal increase in thyroid hormone levels induces osterix (Osx) signaling in hypertrophic chondrocytes to transdifferentiate them into osteoblasts. To test if Osx expressed in chondrocytes directly contributes to transdifferentiation and secondary ossification, we generated Osx flox/flox ; Col2-Cre-ERT2 mice and knocked out Osx with a single injection of tamoxifen at postnatal day (P) 3 prior to evaluation of the epiphyseal bone phenotype by µCT, histology, and immunohistochemistry (IHC) at P21. Vehicle (oil)-treated Osx flox/flox ; Col2-Cre-ERT2 and tamoxifen-treated, Cre-negative Osx flox/flox mice were used as controls. µCT analysis of tibial epiphyses revealed that trabecular bone mass was reduced by 23% in the Osx conditional knockout (cKO) compared with control mice. Trabecular number and thickness were reduced by 28% and 8%, respectively, while trabecular separation was increased by 24% in the cKO mice. Trichrome staining of longitudinal sections of tibial epiphyses showed that bone area and bone area adjusted for total area were decreased by 22% and 18%, respectively. IHC studies revealed the presence of abundant Osx-expressing prehypertrophic chondrocytes in the epiphyses of control mice at P10, but not in the cKO mice. Furthermore, expression levels of MMP13, COL10, ALP, and BSP were considerably reduced in the epiphyses of cKO mice. We also found that Osx overexpression in ATDC5 chondrocytes increased expression of Col10, Mmp13, Alp, and Bsp. Our data indicate that Osx expressed in chondrocytes plays a significant role in secondary ossification by regulating expression of genes involved in chondrocyte hypertrophy and osteoblast transdifferentiation.
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Affiliation(s)
- Weirong Xing
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA 92357 USA
- Department of Medicine, Loma Linda University, Loma Linda, CA 92357 USA
| | - Catrina Godwin
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA 92357 USA
| | - Sheila Pourteymoor
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA 92357 USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, Loma Linda, CA 92357 USA
- Department of Medicine, Loma Linda University, Loma Linda, CA 92357 USA
- Department of Orthopedics, Loma Linda University, Loma Linda, CA 92357 USA
- Department of Biochemistry, Loma Linda University, Loma Linda, CA 92357 USA
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Abstract
PURPOSE OF REVIEW The goal of the review is to summarize the current knowledge on the process of chondrocyte-to-osteoblast transdifferentiation during endochondral bone formation and its potential implications in fracture healing and disease. RECENT FINDINGS Lineage tracing experiments confirmed the transdifferentiation of chondrocytes into osteoblasts. More recent studies lead to the discovery of molecules involved in this process, as well as to the hypothesis that these cells may re-enter a stem cell-like phase prior to their osteoblastic differentiation. This review recapitulates the current knowledge regarding chondrocyte transdifferentiating into osteoblasts, the developmental and postnatal events where transdifferentiation appears to be relevant, and the molecules implicated in this process.
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Affiliation(s)
- Lena Ingeborg Wolff
- Institute of Musculoskeletal Medicine, Department of Bone and Skeletal Research, Medical Faculty of the Westphalian Wilhelms University Münster, Munster, Germany
| | - Christine Hartmann
- Institute of Musculoskeletal Medicine, Department of Bone and Skeletal Research, Medical Faculty of the Westphalian Wilhelms University Münster, Munster, Germany.
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Tong W, Tower RJ, Chen C, Wang L, Zhong L, Wei Y, Sun H, Cao G, Jia H, Pacifici M, Koyama E, Enomoto-Iwamoto M, Qin L. Periarticular Mesenchymal Progenitors Initiate and Contribute to Secondary Ossification Center Formation During Mouse Long Bone Development. Stem Cells 2019; 37:677-689. [PMID: 30681752 DOI: 10.1002/stem.2975] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/19/2018] [Accepted: 12/27/2018] [Indexed: 12/16/2022]
Abstract
Long bone development involves the embryonic formation of a primary ossification center (POC) in the incipient diaphysis followed by postnatal development of a secondary ossification center (SOC) at each epiphysis. Studies have elucidated major basic mechanisms of POC development, but relatively little is known about SOC development. To gain insights into SOC formation, we used Col2-Cre Rosa-tdTomato (Col2/Tomato) reporter mice and found that their periarticular region contained numerous Tomato-positive lineage cells expressing much higher Tomato fluorescence (termed TomatoH ) than underlying epiphyseal chondrocytes (termed TomatoL ). With time, the TomatoH cells became evident at the SOC invagination site and cartilage canal, increased in number in the expanding SOC, and were present as mesenchymal lineage cells in the subchondral bone. These data were verified in two mouse lineage tracing models, Col2-CreER Rosa-tdTomato and Gli1-CreER Rosa-tdTomato. In vitro tests showed that the periarticular TomatoH cells from Col2/Tomato mice contained mesenchymal progenitors with multidifferentiation abilities. During canal initiation, the cells expressed vascular endothelial growth factor (VEGF) and migrated into epiphyseal cartilage ahead of individual or clusters of endothelial cells, suggesting a unique role in promoting vasculogenesis. Later during SOC expansion, chondrocytes in epiphyseal cartilage expressed VEGF, and angiogenic blood vessels preceded TomatoH cells. Gene expression analyses of microdissected samples revealed upregulation of MMPs in periarticular cells at the invagination site and suggested potential roles for novel kinase and growth factor signaling pathways in regulating SOC canal initiation. In summary, our data indicate that the periarticular region surrounding epiphyseal cartilage contains mesenchymal progenitors that initiate SOC development and form subchondral bone. Stem Cells 2019;37:677-689.
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Affiliation(s)
- Wei Tong
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Robert J Tower
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Chider Chen
- Department of Anatomy and Cell Biology, School of Dental Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Luqiang Wang
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Leilei Zhong
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Yulong Wei
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Hao Sun
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Gaoyuan Cao
- Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, New Jersey, USA
| | - Haoruo Jia
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Maurizio Pacifici
- Translational Research Program in Pediatric Orthopaedics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Eiki Koyama
- Translational Research Program in Pediatric Orthopaedics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Motomi Enomoto-Iwamoto
- Department of Orthopaedic Surgery, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Ling Qin
- Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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26
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Poot M. The Right Gene, Expressed at the Wrong Time, or at the Wrong Place. Mol Syndromol 2019; 9:225-227. [PMID: 30733655 PMCID: PMC6362855 DOI: 10.1159/000492608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2018] [Indexed: 11/19/2022] Open
Affiliation(s)
- Martin Poot
- *Martin Poot, Department of Human Genetics, University of W¨rzburg, Biozentrum, Am Hubland, DE-97074 W¨rzburg (Germany), E-Mail
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27
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The art of building bone: emerging role of chondrocyte-to-osteoblast transdifferentiation in endochondral ossification. Bone Res 2018. [PMID: 29928541 DOI: 10.1038/s41413‐018‐0021‐z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
There is a worldwide epidemic of skeletal diseases causing not only a public health issue but also accounting for a sizable portion of healthcare expenditures. The vertebrate skeleton is known to be formed by mesenchymal cells condensing into tissue elements (patterning phase) followed by their differentiation into cartilage (chondrocytes) or bone (osteoblasts) cells within the condensations. During the growth and remodeling phase, bone is formed directly via intramembranous ossification or through a cartilage to bone conversion via endochondral ossification routes. The canonical pathway of the endochondral bone formation process involves apoptosis of hypertrophic chondrocytes followed by vascular invasion that brings in osteoclast precursors to remove cartilage and osteoblast precursors to form bone. However, there is now an emerging role for chondrocyte-to-osteoblast transdifferentiation in the endochondral ossification process. Although the concept of "transdifferentiation" per se is not recent, new data using a variety of techniques to follow the fate of chondrocytes in different bones during embryonic and post-natal growth as well as during fracture repair in adults have identified three different models for chondrocyte-to-osteoblast transdifferentiation (direct transdifferentiation, dedifferentiation to redifferentiation, and chondrocyte to osteogenic precursor). This review focuses on the emerging models of chondrocyte-to-osteoblast transdifferentiation and their implications for the treatment of skeletal diseases as well as the possible signaling pathways that contribute to chondrocyte-to-osteoblast transdifferentiation processes.
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28
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Aghajanian P, Mohan S. The art of building bone: emerging role of chondrocyte-to-osteoblast transdifferentiation in endochondral ossification. Bone Res 2018; 6:19. [PMID: 29928541 PMCID: PMC6002476 DOI: 10.1038/s41413-018-0021-z] [Citation(s) in RCA: 147] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 04/26/2018] [Accepted: 05/02/2018] [Indexed: 12/21/2022] Open
Abstract
There is a worldwide epidemic of skeletal diseases causing not only a public health issue but also accounting for a sizable portion of healthcare expenditures. The vertebrate skeleton is known to be formed by mesenchymal cells condensing into tissue elements (patterning phase) followed by their differentiation into cartilage (chondrocytes) or bone (osteoblasts) cells within the condensations. During the growth and remodeling phase, bone is formed directly via intramembranous ossification or through a cartilage to bone conversion via endochondral ossification routes. The canonical pathway of the endochondral bone formation process involves apoptosis of hypertrophic chondrocytes followed by vascular invasion that brings in osteoclast precursors to remove cartilage and osteoblast precursors to form bone. However, there is now an emerging role for chondrocyte-to-osteoblast transdifferentiation in the endochondral ossification process. Although the concept of "transdifferentiation" per se is not recent, new data using a variety of techniques to follow the fate of chondrocytes in different bones during embryonic and post-natal growth as well as during fracture repair in adults have identified three different models for chondrocyte-to-osteoblast transdifferentiation (direct transdifferentiation, dedifferentiation to redifferentiation, and chondrocyte to osteogenic precursor). This review focuses on the emerging models of chondrocyte-to-osteoblast transdifferentiation and their implications for the treatment of skeletal diseases as well as the possible signaling pathways that contribute to chondrocyte-to-osteoblast transdifferentiation processes.
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Affiliation(s)
- Patrick Aghajanian
- Musculoskeletal Disease Center, Veterans Affairs Loma Linda Healthcare System, Loma Linda, California USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, Veterans Affairs Loma Linda Healthcare System, Loma Linda, California USA
- Department of Medicine, Loma Linda University, Loma Linda, California USA
- Department of Orthopedics, Loma Linda University, Loma Linda, California USA
- Department of Biochemistry, Loma Linda University, Loma Linda, California USA
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