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Bajpai AK, Gu Q, Jiao Y, Starlard-Davenport A, Gu W, Quarles LD, Xiao Z, Lu L. Systems genetics and bioinformatics analyses using ESR1-correlated genes identify potential candidates underlying female bone development. Genomics 2024; 116:110769. [PMID: 38141931 PMCID: PMC10811775 DOI: 10.1016/j.ygeno.2023.110769] [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: 07/22/2023] [Revised: 11/14/2023] [Accepted: 12/18/2023] [Indexed: 12/25/2023]
Abstract
Estrogen receptor α (ESR1) is involved in E2 signaling and plays a major role in postmenopausal bone loss. However, the molecular network underlying ESR1 has not been explored. We used systems genetics and bioinformatics to identify important genes associated with Esr1 in postmenopausal bone loss. We identified ~2300 Esr1-coexpressed genes in female BXD bone femur, functional analysis of which revealed 'osteoblast signaling' as the most enriched pathway. PPI network led to the identification of 25 'female bone candidates'. The gene-regulatory analysis revealed RUNX2 as a key TF. ANKRD1 and RUNX2 were significantly different between osteoporosis patients and healthy controls. Sp7, Col1a1 and Pth1r correlated with multiple femur bone phenotypes in BXD mice. miR-3121-3p targeted Csf1, Ankrd1, Sp7 and Runx2. β-estradiol treatment markedly increased the expression of these candidates in mouse osteoblast. Our study revealed that Esr1-correlated genes Ankrd1, Runx2, Csf1 and Sp7 may play important roles in female bone development.
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Affiliation(s)
- Akhilesh K Bajpai
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Qingqing Gu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA; Department of Cardiology, Affiliated Hospital of Nantong University, Jiangsu 226001, China
| | - Yan Jiao
- Department of Orthopaedic Surgery and Biomedical Engineering, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Athena Starlard-Davenport
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Weikuan Gu
- Department of Orthopaedic Surgery and Biomedical Engineering, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Leigh Darryl Quarles
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Zhousheng Xiao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA.
| | - Lu Lu
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, USA.
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2
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Peng S, He T, Liu Y, Zheng L, Zhong Y, Niu Z, Zhang M, Yang S. Lnc-PPP2R1B Mediates the Alternative Splicing of PPP2R1B by Interacting and Stabilizing HNRNPLL and Promotes Osteogenesis of MSCs. Stem Cell Rev Rep 2023; 19:1981-1993. [PMID: 37243830 DOI: 10.1007/s12015-023-10559-5] [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] [Accepted: 05/08/2023] [Indexed: 05/29/2023]
Abstract
Osteogeinc differentiation from mesenchymal stem cells (MSCs) into osteoblasts is a key step for bone tissue engineering in regenerative medicine. The insight into regulatory mechanism of osteogenesis of MSCs facilitates achieving better recovery effect. Long non-coding RNAs are regarded as a family of important moderators in osteogenesis. In this study, we found a novel lncRNA, lnc-PPP2R1B was up-regulated during osteogenesis of MSCs by Illumina HiSeq transcritome sequencing. We demonstrated lnc-PPP2R1B overexpression promoted osteogenesis and knockdown of lnc-PPP2R1B inhibited osteogenesis of MSCs. Mechanically, it physically interacted with and up-regulated heterogeneous nuclear ribonucleoprotein L Like (HNRNPLL), which is a master regulator of activation-induced alternative splicing in T cells. We found lnc-PPP2R1B knockdown or HNRNPLL knockdown decreased transcript-201 of Protein Phosphatase 2A, Regulatory Subunit A, Beta Isoform (PPP2R1B) while increased transcript-203 of PPP2R1B, and did not affect transcript-202/204/206. PPP2R1B is a constant regulatory subunit of protein phosphatase 2 (PP2A), which activates Wnt/β-catenin pathway by removing phosphorylation and stabilization of β-catenin and translocation into nucleus. The transcript-201 retained exon 2 and 3, compared to transcript-203. And it was reported the exon 2 and 3 of PPP2R1B were one part of B subunit binding domain on A subunit in PP2A trimer, and therefore retaining exon 2 and 3 promised formation and enzyme function of PP2A. Finally, lnc-PPP2R1B promoted ectopic osteogenesis in vivo. Conclusively, lnc-PPP2R1B mediated alternative splicing of PPP2R1B through retaining exon 2 and 3 by interacting with HNRNPLL and then promoted osteogenesis, which may facilitate an in-depth understanding of function and mechanism of lncRNAs in osteogenesis. Lnc-PPP2R1B interacted with HNRNPLL, and regulated alternative splicing of PPP2R1B through retaining exon 2 and 3, which preserved enzyme function of PP2A and enhanced dephosphorylation and nuclear translocation of β-catenin, thereby promoting Runx2 and OSX expression and then osteogenesis. And it provided experimental data and potential target for promoting bone formation and bone regeneration.
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Affiliation(s)
- Shuping Peng
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China.
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China.
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China.
| | - Tiantian He
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Ying Liu
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Leliang Zheng
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Yancheng Zhong
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Zhiyuan Niu
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Mojian Zhang
- NHC Key Laboratory of Carcinogenesis and Hunan Key Laboratory of Cancer Metabolism, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, China
- Key Laboratory of Carcinogenesis and Cancer Invasion of the Chinese Ministry of Education, Cancer Research Institute, Xiangya Hospital, Central South University, Changsha, Hunan, China
- Hunan Key Laboratory of Non Resolving Inflammation and Cancer, Disease Genome Research Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Sheng Yang
- The Reproduction Medical Center, the Third Affiliated Hospital of Shenzhen University, Shenzhen, China.
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3
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Roles of Local Soluble Factors in Maintaining the Growth Plate: An Update. Genes (Basel) 2023; 14:genes14030534. [PMID: 36980807 PMCID: PMC10048135 DOI: 10.3390/genes14030534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/16/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
The growth plate is a cartilaginous tissue found at the ends of growing long bones, which contributes to the lengthening of bones during development. This unique structure contains at least three distinctive layers, including resting, proliferative, and hypertrophic chondrocyte zones, maintained by a complex regulatory network. Due to its soft tissue nature, the growth plate is the most susceptible tissue of the growing skeleton to injury in childhood. Although most growth plate damage in fractures can heal, some damage can result in growth arrest or disorder, impairing leg length and resulting in deformity. In this review, we re-visit previously established knowledge about the regulatory network that maintains the growth plate and integrate current research displaying the most recent progress. Next, we highlight local secretary factors, such as Wnt, Indian hedgehog (Ihh), and parathyroid hormone-related peptide (PTHrP), and dissect their roles and interactions in maintaining cell function and phenotype in different zones. Lastly, we discuss future research topics that can further our understanding of this unique tissue. Given the unmet need to engineer the growth plate, we also discuss the potential of creating particular patterns of soluble factors and generating them in vitro.
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Krishnan RH, Sadu L, Akshaya RL, Gomathi K, Saranya I, Das UR, Satishkumar S, Selvamurugan N. Circ_CUX1/miR-130b-5p/p300 axis for parathyroid hormone-stimulation of Runx2 activity in rat osteoblasts: A combined bioinformatic and experimental approach. Int J Biol Macromol 2023; 225:1152-1163. [PMID: 36427609 DOI: 10.1016/j.ijbiomac.2022.11.176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 10/31/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022]
Abstract
Parathyroid hormone (PTH) regulates the expression of bone remodeling genes by enhancing the activity of Runx2 in osteoblasts. p300, a histone acetyltransferase, acetylated Runx2 to activate the expression of its target genes. PTH stimulated the expression of p300 in rat osteoblastic cells. Increasing studies suggested the potential of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs) and circular RNAs (circRNAs), in regulating gene expression under both physiological and pathological conditions. In this study, we hypothesized that PTH regulates Runx2 activity via ncRNAs-mediated p300 expression in rat osteoblastic cells. Bioinformatics and experimental approaches identified PTH-upregulation of miR-130b-5p and circ_CUX1 that putatively target p300 and miR-130b-5p, respectively. An antisense-mediated knockdown of circ_CUX1 was performed to determine the sponging activity of circ_CUX1. Knockdown of circ_CUX1 promoted miR-130b-5p activity and reduced p300 expression, resulting in decreased Runx2 acetylation in rat osteoblastic cells. Further, bioinformatics analysis identified the possible signaling pathways that regulate Runx2 activity and osteoblast differentiation via circ_CUX1/miR-130b-5p/p300 axis. The predicted circ_CUX1/miR-130b-5p/p300 axis might pave the way for better diagnostic and therapeutic approaches for bone-related diseases.
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Affiliation(s)
- R Hari Krishnan
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - Lakshana Sadu
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - R L Akshaya
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - K Gomathi
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - I Saranya
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - Udipt Ranjan Das
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - Sneha Satishkumar
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India
| | - N Selvamurugan
- Department of Biotechnology, College of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603 203, Tamil Nadu, India.
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Stamnitz S, Krawczenko A, Szałaj U, Górecka Ż, Antończyk A, Kiełbowicz Z, Święszkowski W, Łojkowski W, Klimczak A. Osteogenic Potential of Sheep Mesenchymal Stem Cells Preconditioned with BMP-2 and FGF-2 and Seeded on an nHAP-Coated PCL/HAP/β-TCP Scaffold. Cells 2022; 11:3446. [PMID: 36359842 PMCID: PMC9659177 DOI: 10.3390/cells11213446] [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: 09/22/2022] [Revised: 10/20/2022] [Accepted: 10/28/2022] [Indexed: 08/30/2023] Open
Abstract
Mesenchymal stem cells (MSCs) attract interest in regenerative medicine for their potential application in bone regeneration. However, direct transplantation of cells into damaged tissue is not efficient enough to regenerate large bone defects. This problem could be solved with a biocompatible scaffold. Consequently, bone tissue engineering constructs based on biomaterial scaffolds, MSCs, and osteogenic cytokines are promising tools for bone regeneration. The aim of this study was to evaluate the effect of FGF-2 and BMP-2 on the osteogenic potential of ovine bone marrow-derived MSCs seeded onto an nHAP-coated PCL/HAP/β-TCP scaffold in vitro and its in vivo biocompatibility in a sheep model. In vitro analysis revealed that cells preconditioned with FGF-2 and BMP-2 showed a better capacity to adhere and proliferate on the scaffold than untreated cells. BM-MSCs cultured in an osteogenic medium supplemented with FGF-2 and BMP-2 had the highest osteogenic differentiation potential, as assessed based on Alizarin Red S staining and ALP activity. qRT-PCR analysis showed increased expression of osteogenic marker genes in FGF-2- and BMP-2-treated BM-MSCs. Our pilot in vivo research showed that the implantation of an nHAP-coated PCL/HAP/β-TCP scaffold with BM-MSCs preconditioned with FGF-2 and BMP-2 did not have an adverse effect in the sheep mandibular region and induced bone regeneration. The biocompatibility of the implanted scaffold-BM-MSC construct with sheep tissues was confirmed by the expression of early (collagen type I) and late (osteocalcin) osteogenic proteins and a lack of an elevated level of proinflammatory cytokines. These findings suggest that FGF-2 and BMP-2 enhance the osteogenic differentiation potential of MSCs grown on a scaffold, and that such a tissue engineering construct may be used to regenerate large bone defects.
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Affiliation(s)
- Sandra Stamnitz
- Laboratory of Biology of Stem and Neoplastic Cells, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, R. Weigla 12, 53-114 Wroclaw, Poland
| | - Agnieszka Krawczenko
- Laboratory of Biology of Stem and Neoplastic Cells, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, R. Weigla 12, 53-114 Wroclaw, Poland
| | - Urszula Szałaj
- Laboratory of Nanostructures and Nanomedicine, Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, 01-142 Warsaw, Poland
| | - Żaneta Górecka
- Division of Materials Design, Faculty of Materials Science and Engineering, Warsaw University of Technology, 141 Woloska Str., 02-507 Warsaw, Poland
| | - Agnieszka Antończyk
- Department of Surgery, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 51, 50-366 Wroclaw, Poland
| | - Zdzisław Kiełbowicz
- Department of Surgery, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, pl. Grunwaldzki 51, 50-366 Wroclaw, Poland
| | - Wojciech Święszkowski
- Division of Materials Design, Faculty of Materials Science and Engineering, Warsaw University of Technology, 141 Woloska Str., 02-507 Warsaw, Poland
| | - Witold Łojkowski
- Laboratory of Nanostructures and Nanomedicine, Institute of High Pressure Physics, Polish Academy of Sciences, Sokolowska 29/37, 01-142 Warsaw, Poland
| | - Aleksandra Klimczak
- Laboratory of Biology of Stem and Neoplastic Cells, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, R. Weigla 12, 53-114 Wroclaw, Poland
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Zhang J, Li YZ, Chen WQ, Yuan JY, Li Q, Meng YX, Yu YD, Guo Q. Genome sequencing identified a novel exonic microdeletion in the RUNX2 gene that causes cleidocranial dysplasia. Clin Chim Acta 2022; 528:6-12. [DOI: 10.1016/j.cca.2022.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/14/2022] [Accepted: 01/16/2022] [Indexed: 11/30/2022]
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7
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Graphene-Oxide Porous Biopolymer Hybrids Enhance In Vitro Osteogenic Differentiation and Promote Ectopic Osteogenesis In Vivo. Int J Mol Sci 2022; 23:ijms23010491. [PMID: 35008918 PMCID: PMC8745160 DOI: 10.3390/ijms23010491] [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: 12/05/2021] [Revised: 12/20/2021] [Accepted: 12/29/2021] [Indexed: 11/17/2022] Open
Abstract
Over the years, natural-based scaffolds have presented impressive results for bone tissue engineering (BTE) application. Further, outstanding interactions have been observed during the interaction of graphene oxide (GO)-reinforced biomaterials with both specific cell cultures and injured bone during in vivo experimental conditions. This research hereby addresses the potential of fish gelatin/chitosan (GCs) hybrids reinforced with GO to support in vitro osteogenic differentiation and, further, to investigate its behavior when implanted ectopically. Standard GCs formulation was referenced against genipin (Gp) crosslinked blend and 0.5 wt.% additivated GO composite (GCsGp/GO 0.5 wt.%). Pre-osteoblasts were put in contact with these composites and induced to differentiate in vitro towards mature osteoblasts for 28 days. Specific bone makers were investigated by qPCR and immunolabeling. Next, CD1 mice models were used to assess de novo osteogenic potential by ectopic implantation in the subcutaneous dorsum pocket of the animals. After 4 weeks, alkaline phosphate (ALP) and calcium deposits together with collagen synthesis were investigated by biochemical analysis and histology, respectively. Further, ex vivo materials were studied after surgery regarding biomineralization and morphological changes by means of qualitative and quantitative methods. Furthermore, X-ray diffraction and Fourier-transform infrared spectroscopy underlined the newly fashioned material structuration by virtue of mineralized extracellular matrix. Specific bone markers determination stressed the osteogenic phenotype of the cells populating the material in vitro and successfully differentiated towards mature bone cells. In vivo results of specific histological staining assays highlighted collagen formation and calcium deposits, which were further validated by micro-CT. It was observed that the addition of 0.5 wt.% GO had an overall significant positive effect on both in vitro differentiation and in vivo bone cell recruitment in the subcutaneous region. These data support the GO bioactivity in osteogenesis mechanisms as being self-sufficient to elevate osteoblast differentiation and bone formation in ectopic sites while lacking the most common osteoinductive agents.
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Inchingolo AD, Patano A, Coloccia G, Ceci S, Inchingolo AM, Marinelli G, Malcangi G, Montenegro V, Laudadio C, Palmieri G, Bordea IR, Ponzi E, Orsini P, Ficarella R, Scarano A, Lorusso F, Dipalma G, Corsalini M, Gentile M, Venere DD, Inchingolo F. Genetic Pattern, Orthodontic and Surgical Management of Multiple Supplementary Impacted Teeth in a Rare, Cleidocranial Dysplasia Patient: A Case Report. MEDICINA (KAUNAS, LITHUANIA) 2021; 57:medicina57121350. [PMID: 34946295 PMCID: PMC8709258 DOI: 10.3390/medicina57121350] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/30/2021] [Accepted: 12/08/2021] [Indexed: 12/12/2022]
Abstract
Background: Cleidocranial dysplasia (CCD) is a rare, autosomal dominant skeletal dysplasia with a prevalence of one per million births. The main causes of CCD are mutations in the core-binding factor alpha-1 (CBFA1) or runt-related transcription factor-2 (RUNX2), located at the 6p21 chromosomal region. RUNX2 plays important roles in osteoblast differentiation, chondrocyte proliferation and differentiation, and tooth formation. The disease is characterized by clavicular aplasia or hypoplasia, Wormian bones, delayed closure of cranial suture, brachycephalic head, maxillary deficiency, retention of primary teeth, inclusion of permanent teeth, and multiple supernumerary teeth. Materials and Methods: A 22-year-old girl suffering from cleidocranial dysplasia with short stature, narrow shoulders, craniofacial manifestations (short face, broad forehead, etc.) and dental anomalies (different lower dental elements under eruption, supernumerary and impacted multiple teeth, etc.) was examined at our service (Complex Operative Unit of Odontostomatology of Policlinico of Bari). RX Orthopantomography (OPG) and cone beam computed tomography (CBCT) were requested to better assess the position of the supernumerary teeth and their relationships with others and to evaluate the bone tissue. Results: Under eruption was probably caused by dental interferences with supernumerary teeth; hence, extractions of supernumerary upper canines and lower premolars were performed under general anaesthesia. Surgery outcome was excellent with good tissue healing and improvements in the therapeutic possibilities with future orthodontics. Conclusions: The objective of this article is to give an update about radiological, clinical, and molecular features of CCD and to alert the health team about the importance of establishing an early diagnosis and an appropriate treatment in these patients to prevent impacted teeth complications and to offer them a better quality of life.
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Affiliation(s)
- Alessio Danilo Inchingolo
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Assunta Patano
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Giovanni Coloccia
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Sabino Ceci
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Angelo Michele Inchingolo
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Grazia Marinelli
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Giuseppina Malcangi
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Valentina Montenegro
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Claudia Laudadio
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Giulia Palmieri
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Ioana Roxana Bordea
- Department of Oral Rehabilitation, Faculty of Dentistry, Iuliu Hațieganu University of Medicine and Pharmacy, 400012 Cluj-Napoca, Romania
- Correspondence: or (I.R.B.); or (F.L.); (F.I.); Tel.: +40-744919319 (I.R.B.); +39-3282132586 (F.L.); +39-3312111104 (F.I.)
| | - Emanuela Ponzi
- Medical Genetics Unit, Department of Human Reproductive Medicine, ASL Bari, 70121 Bari, Italy; (E.P.); (P.O.); (R.F.); (M.G.)
| | - Paola Orsini
- Medical Genetics Unit, Department of Human Reproductive Medicine, ASL Bari, 70121 Bari, Italy; (E.P.); (P.O.); (R.F.); (M.G.)
| | - Romina Ficarella
- Medical Genetics Unit, Department of Human Reproductive Medicine, ASL Bari, 70121 Bari, Italy; (E.P.); (P.O.); (R.F.); (M.G.)
| | - Antonio Scarano
- Department of Innovative Technologies in Medicine and Dentistry, University of Chieti-Pescara, 66100 Chieti, Italy;
| | - Felice Lorusso
- Department of Innovative Technologies in Medicine and Dentistry, University of Chieti-Pescara, 66100 Chieti, Italy;
- Correspondence: or (I.R.B.); or (F.L.); (F.I.); Tel.: +40-744919319 (I.R.B.); +39-3282132586 (F.L.); +39-3312111104 (F.I.)
| | - Gianna Dipalma
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Massimo Corsalini
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Mattia Gentile
- Medical Genetics Unit, Department of Human Reproductive Medicine, ASL Bari, 70121 Bari, Italy; (E.P.); (P.O.); (R.F.); (M.G.)
| | - Daniela Di Venere
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
| | - Francesco Inchingolo
- Department of Interdisciplinary Medicine, University of Bari “Aldo Moro”, 70124 Bari, Italy; (A.D.I.); (A.P.); (G.C.); (S.C.); (A.M.I.); (G.M.); (G.M.); (V.M.); (C.L.); (G.P.); (G.D.); (M.C.); (D.D.V.)
- Correspondence: or (I.R.B.); or (F.L.); (F.I.); Tel.: +40-744919319 (I.R.B.); +39-3282132586 (F.L.); +39-3312111104 (F.I.)
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Li H, Xiao Z, Quarles LD, Li W. Osteoporosis: Mechanism, Molecular Target and Current Status on Drug Development. Curr Med Chem 2021; 28:1489-1507. [PMID: 32223730 PMCID: PMC7665836 DOI: 10.2174/0929867327666200330142432] [Citation(s) in RCA: 93] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 11/22/2022]
Abstract
CDATA[Osteoporosis is a pathological loss of bone mass due to an imbalance in bone remodeling where osteoclast-mediated bone resorption exceeds osteoblast-mediated bone formation resulting in skeletal fragility and fractures. Anti-resorptive agents, such as bisphosphonates and SERMs, and anabolic drugs that stimulate bone formation, including PTH analogues and sclerostin inhibitors, are current treatments for osteoporosis. Despite their efficacy, severe side effects and loss of potency may limit the long term usage of a single drug. Sequential and combinational use of current drugs, such as switching from an anabolic to an anti-resorptive agent, may provide an alternative approach. Moreover, there are novel drugs being developed against emerging new targets such as Cathepsin K and 17β-HSD2 that may have less side effects. This review will summarize the molecular mechanisms of osteoporosis, current drugs for osteoporosis treatment, and new drug development strategies.
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Affiliation(s)
- Hanxuan Li
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Zhousheng Xiao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38165, USA
| | - L. Darryl Quarles
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38165, USA
| | - Wei Li
- Department of Pharmaceutical Sciences, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
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Yao W, Zhang H, Fakhar-E-Alam Kulyar M, Ding Y, Waqas M, Mehmood K, Iqbal M, Du H, Jiang X, Li J. Effect of total flavonoids of Rhizoma Drynariae in thiram induced cytotoxicity of chondrocyte via BMP-2/Runx2 and IHH/PTHrP expressions. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 206:111194. [PMID: 32866894 DOI: 10.1016/j.ecoenv.2020.111194] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 08/14/2020] [Accepted: 08/17/2020] [Indexed: 06/11/2023]
Abstract
Tibial Dyschondroplasia (TD) is a prevailing skeletal disorder that mainly affects rapidly growing avian species. It results in reduced bone strength, lameness and an increase risk of fragility fractures. Total flavonoids of Rhizoma drynariae (TFRD) have been used as an effective treatment of different bone diseases in humans. The current in vitro study was conducted to explore the therapeutic effect of TFRD on thiram-induced cytotoxicity in avian growth plate cells via bone morphogenetic protein-2/runt related transcription factor-2 (BMP-2/Runx2) and Indian hedgehog/Parathyroid hormone-related peptide (IHH/PTHrP) expressions. Chondrocytes were isolated, cultured and refined from chicken's tibial growth plates in a special medium. Then chondrocytes were treated with sublethal thiram having less concentration (2.5 μg/mL) to induce cytotoxicity of chondrocyte, and then treated with providential doses (100 μg/mL) of TFRD. Thiram caused distorted morphology of chondrocytes, nuclei appeared disintegration or lysed along with decreased expressions of BMP-2/Runx2 and IHH/PTHrP. TFRD administration not only enhanced the viability of chondrocytes by itself, but also well restored the damage caused by thiram on growth plate chondrocytes by significantly up-regulating the expressions of BMP-2/Runx2 and IHH/PTHrP. Therefore, this study provides a novel insight into the further treatment of TD and other skeletal ailments and lays the foundation for prevention and treatment.
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Affiliation(s)
- Wangyuan Yao
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Hui Zhang
- South China Agricultural University College of Veterinary Medicine Guangzhou, 510000, PR China
| | | | - Yanmei Ding
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Muhammad Waqas
- Faculty of Veterinary & Animal Sciences, University of the Poonch, Rawalakot, District Poonch, 12350, Azad Jammu & Kashmir, Pakistan
| | - Khalid Mehmood
- Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, 63100, Pakistan
| | - Mujahid Iqbal
- Department of Pathology, Cholistan University of Veterinary and Animal Sciences, Bahawalpur, 63100, Pakistan
| | - Haitao Du
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Xiong Jiang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Jiakui Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, PR China; College of Animals Husbandry and Veterinary Medicine, Tibet Agricultural and Animal Husbandry University, Linzhi, Tibet, 860000, PR China.
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11
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Liu Q, Li M, Wang S, Xiao Z, Xiong Y, Wang G. Recent Advances of Osterix Transcription Factor in Osteoblast Differentiation and Bone Formation. Front Cell Dev Biol 2020; 8:601224. [PMID: 33384998 PMCID: PMC7769847 DOI: 10.3389/fcell.2020.601224] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/23/2020] [Indexed: 12/14/2022] Open
Abstract
With increasing life expectations, more and more patients suffer from fractures either induced by intensive sports or other bone-related diseases. The balance between osteoblast-mediated bone formation and osteoclast-mediated bone resorption is the basis for maintaining bone health. Osterix (Osx) has long been known to be an essential transcription factor for the osteoblast differentiation and bone mineralization. Emerging evidence suggests that Osx not only plays an important role in intramembranous bone formation, but also affects endochondral ossification by participating in the terminal cartilage differentiation. Given its essentiality in skeletal development and bone formation, Osx has become a new research hotspot in recent years. In this review, we focus on the progress of Osx's function and its regulation in osteoblast differentiation and bone mass. And the potential role of Osx in developing new therapeutic strategies for osteolytic diseases was discussed.
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Affiliation(s)
- Qian Liu
- Key Laboratory of Brain and Neuroendocrine Diseases, College of Hunan Province, Hunan University of Medicine, Huaihua, China
- Biomedical Research Center, Hunan University of Medicine, Huaihua, China
| | - Mao Li
- Biomedical Research Center, Hunan University of Medicine, Huaihua, China
| | - Shiyi Wang
- XiangYa School of Medicine, Central South University, Changsha, China
| | - Zhousheng Xiao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Yuanyuan Xiong
- Key Laboratory of Brain and Neuroendocrine Diseases, College of Hunan Province, Hunan University of Medicine, Huaihua, China
- Department of Neurosurgery, The Second Affiliated Hospital of Nanchang University, Nanchang, China
| | - Guangwei Wang
- Key Laboratory of Brain and Neuroendocrine Diseases, College of Hunan Province, Hunan University of Medicine, Huaihua, China
- Biomedical Research Center, Hunan University of Medicine, Huaihua, China
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12
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Küchler EC, Reis CLB, Carelli J, Scariot R, Nelson-Filho P, Coletta RD, Paza AO, Matsumoto MAN, Proff P, Kirschneck C. Potential interactions among single nucleotide polymorphisms in bone- and cartilage-related genes in skeletal malocclusions. Orthod Craniofac Res 2020; 24:277-287. [PMID: 33068497 DOI: 10.1111/ocr.12433] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 09/07/2020] [Accepted: 10/08/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To investigate SNPs in bone- and cartilage-related genes and their interaction in the aetiology of sagittal and vertical skeletal malocclusions. SETTINGS AND SAMPLE POPULATION This study included 143 patients and classified as follows: skeletal class I (n = 77), class II (n = 47) and class III (n = 19); maxillary retrusion (n = 39), protrusion (n = 52) and well-positioned maxilla (n = 52); mandibular retrognathism (n = 50), prognathism (n = 50) and well-positioned mandible (n = 43); normofacial (n = 72), dolichofacial (n = 55) and brachyfacial (n = 16). MATERIALS AND METHODS Steiner's ANB, SNA, SNB angles and Ricketts' NBa-PtGn angle were measured to determine the skeletal malocclusion and the vertical pattern. Nine SNPs in BMP2, BMP4, SMAD6, RUNX2, WNT3A and WNT11 were genotyped. Chi-squared test was used to compare genotypes among the groups. Multifactor dimensionality reduction (MDR) and binary logistic regression analysis, both using gender and age as co-variables, were also used. We performed Bonferroni correction for multiple testing. RESULTS Significant associations at P < .05 were observed for SNPs rs1005464 (P = .042) and rs235768 (P = .021) in BMP2 with mandibular retrognathism and for rs59983488 (RUNX2) with maxillary protrusion (P = .04) as well as for rs708111 (WNT3A) with skeletal class III (P = .02; dominant model), rs1533767 (WNT11) with a brachyfacial skeletal pattern (P = .01, OR = 0.10; dominant model) and for rs3934908 (SMAD6) with prognathism (P = .02; recessive model). After the Bonferroni correction, none of the SNPs remained associated. The MDR predicted some interaction for skeletal class II, dolichofacial and brachyfacial phenotypes. CONCLUSION Our results suggest that SNPs in BMP2, BMP4, SMAD6, RUNX2, WNT3A and WNT11 could be involved in the aetiology of sagittal and vertical malocclusions.
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Affiliation(s)
- Erika Calvano Küchler
- Department of Orthodontics, University Medical Centre of Regensburg, Regensburg, Germany
| | - Caio Luiz Bitencourt Reis
- Department of Clinic and Surgery, School of Dentistry, Federal University of Alfenas, Alfenas, Brazil
| | - Julia Carelli
- Department of Dentistry, School of Dentistry, Univille (Joinville University), Joinville, Brazil
| | - Rafaela Scariot
- Department of Stomatology, Federal University of Paraná, Curitiba, Brazil
| | - Paulo Nelson-Filho
- Department of Pediatric Dentistry, School of Dentistry of Ribeirão Preto, USP - Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Ricardo D Coletta
- Department of Oral Diagnosis, School of Dentistry of Piracicaba, University of Campinas (UNICAMP), Campinas, Brazil
| | - Aleysson Olimpio Paza
- Department of Dentistry, School of Dentistry, Univille (Joinville University), Joinville, Brazil
| | - Mírian Aiko Nakane Matsumoto
- Department of Pediatric Dentistry, School of Dentistry of Ribeirão Preto, USP - Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Peter Proff
- Department of Orthodontics, University Medical Centre of Regensburg, Regensburg, Germany
| | - Christian Kirschneck
- Department of Orthodontics, University Medical Centre of Regensburg, Regensburg, Germany
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Zhang B, Zhang X, Xiao J, Zhou X, Chen Y, Gao C. Neuropeptide Y upregulates Runx2 and osterix and enhances osteogenesis in mouse MC3T3‑E1 cells via an autocrine mechanism. Mol Med Rep 2020; 22:4376-4382. [PMID: 33000198 PMCID: PMC7533442 DOI: 10.3892/mmr.2020.11506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 08/20/2020] [Indexed: 12/23/2022] Open
Abstract
The neuropeptide Y (NPY) system is considered one of the primary neural signaling pathways. NPY, produced by osteoblasts and other peripheral tissues, is known to inhibit biological functions of osteoblasts. However, until recently, little was known of the autocrine mechanism by which NPY is regulated. To investigate this mechanism, overexpression plasmids and small interfering RNA (siRNA) targeting NPY were transfected into the MC3T3-E1 cell line to observe its effects on osteogenesis. NPY overexpression was found to markedly enhance the osteogenic ability of MC3T3-E1 cells by an autocrine mechanism, coincident with the upregulation of osterix and runt-related transcription factor 2 (Runx2). Furthermore, NPY increased the activities of alkaline phosphatase (ALP) and osteocalcin (OCN) by upregulating their osteoblastic expression in vitro (as well as that of osterix and Runx2). Following transfection with NPY-siRNA, the osteoblastic ability of MC3T3-E1 cells was markedly decreased, and NPY deficiency inhibited the protein expression of osterix, Runx2, OCN and ALP in primary osteoblasts. Collectively, these results indicated that NPY played an important role in osteoblast differentiation by regulating the osterix and Runx2 pathways.
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Affiliation(s)
- Bo Zhang
- Department of Joint Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250033, P.R. China
| | - Xiaolei Zhang
- Department of Obstetrics and Gynecology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P.R. China
| | - Juan Xiao
- Department of Evidence‑Based Medicine, Institute of Medical Sciences, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250033, P.R. China
| | - Xuguang Zhou
- Department of Joint Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250033, P.R. China
| | - Yuan Chen
- Departments of Central Research Lab, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250033, P.R. China
| | - Chunzheng Gao
- Departments of Spinal Surgery, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250033, P.R. China
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Rahim F, Abbasi Pashaki P, Jafarisani M, Ghorbani F, Ebrahimi A. Runx2 silencing promotes adipogenesis via down-regulation of DLK1 in chondrogenic differentiating MSCs. J Gene Med 2020; 22:e3244. [PMID: 32559818 DOI: 10.1002/jgm.3244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/16/2020] [Accepted: 06/17/2020] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND For cartilage regeneration, stem cells are a promising cell source; however, even the advances made in the differentiation of stem cells into precursor-differentiated cartilage cells have not been successful with respect to reprograming these cells to achieve complete differentiation and fully functioning cells until now. Previous findings suggest that Runx2 plays a major role in chondrocyte differentiation and maturation. Although targeting Runx2 has enhanced some chondrocyte properties, the adipogenic lineage shift has eventually occurred in these cells. The present study mainly aimed to reveal the mechanism of this adipogenesis. METHODS To create inducible artificial shRNA-miR expressing vectors, the designed short hairpin RNAs (shRNAs) were inserted into the pri-mir-30 backbone, cloned into lentiviral pLVET-Tet-on, and transducted into mesenchymal stem cells (MSCs). Runx2 gene was silenced in MSCs either for 1 week or 4 weeks and cultured in the chondrogenic medium. At days 7, 14 and 28, cells were harvested, and chondrogenesis, adipogenesis and hypertrophic states were examined using histochemical staining and a real-time polymerase chain reaction assay. RESULTS The results showed that the designed shRNA-miR effectively targeted Runx2 in mRNA and protein levels. Chondrogenic markers were up-regulated in constantly silenced Runx2 group; however, adipogenic markers and fat droplets appeared gradually. DLK1 gene was also significantly down-regulated in this group, and overexpression of DLK1 abrogated adipogenesis in the Runx2 targeted group. CONCLUSIONS Based on these results, it can be concluded that DLK1 is responsible for the lineage shift in Runx2 targeted chondrogenic differentiating MSCs.
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Affiliation(s)
- Fakher Rahim
- Thalassemia and Hemoglobinopathy Research Centre, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | | | - Moslem Jafarisani
- Department of Biochemistry, School of Medicine, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Fatemeh Ghorbani
- Student Research Committee, Guilan University of Medical Sciences, Rasht, Iran
| | - Ammar Ebrahimi
- Department of Medical Biotechnology, School of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran
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15
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Komori T. Molecular Mechanism of Runx2-Dependent Bone Development. Mol Cells 2020; 43:168-175. [PMID: 31896233 PMCID: PMC7057844 DOI: 10.14348/molcells.2019.0244] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 12/03/2019] [Indexed: 01/09/2023] Open
Abstract
Runx2 is an essential transcription factor for skeletal development. It is expressed in multipotent mesenchymal cells, osteoblast-lineage cells, and chondrocytes. Runx2 plays a major role in chondrocyte maturation, and Runx3 is partly involved. Runx2 regulates chondrocyte proliferation by directly regulating Ihh expression. It also determines whether chondrocytes become those that form transient cartilage or permanent cartilage, and functions in the pathogenesis of osteoarthritis. Runx2 is essential for osteoblast differentiation and is required for the proliferation of osteoprogenitors. Ihh is required for Runx2 expression in osteoprogenitors, and hedgehog signaling and Runx2 induce the differentiation of osteoprogenitors to preosteoblasts in endochondral bone. Runx2 induces Sp7 expression, and Runx2, Sp7, and canonical Wnt signaling are required for the differentiation of preosteoblasts to immature osteoblasts. It also induces the proliferation of osteoprogenitors by directly regulating the expression of Fgfr2 and Fgfr3. Furthermore, Runx2 induces the proliferation of mesenchymal cells and their commitment into osteoblast-lineage cells through the induction of hedgehog (Gli1, Ptch1, Ihh), Fgf (Fgfr2, Fgfr3), Wnt (Tcf7, Wnt10b), and Pthlh (Pth1r) signaling pathway gene expression in calvaria, and more than a half-dosage of Runx2 is required for their expression. This is a major cause of cleidocranial dysplasia, which is caused by heterozygous mutation of RUNX2. Cbfb, which is a co-transcription factor that forms a heterodimer with Runx2, enhances DNA binding of Runx2 and stabilizes Runx2 protein by inhibiting its ubiquitination. Thus, Runx2/Cbfb regulates the proliferation and differentiation of chondrocytes and osteoblast-lineage cells by activating multiple signaling pathways and via their reciprocal regulation.
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Affiliation(s)
- Toshihisa Komori
- Basic and Translational Research Center for Hard Tissue Disease, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki 852-8588, Japan
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Adipose-Derived Stem Cells and Ceiling Culture-Derived Preadipocytes Cultured from Subcutaneous Fat Tissue Differ in Their Epigenetic Characteristics and Osteogenic Potential. Plast Reconstr Surg 2020; 144:644-655. [PMID: 31461020 DOI: 10.1097/prs.0000000000005913] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Adipose-derived stem cells and ceiling culture-derived preadipocytes can be harvested from subcutaneous adipose tissue. Little is known about the epigenetic differences, which may contribute to differences in osteogenic potential, between these cell types. The purpose of this study was to address the osteogenic potential and underlying epigenetic status of adipose-derived stem cells and ceiling culture-derived preadipocytes. METHODS Adipose-derived stem cells and ceiling culture-derived preadipocytes were cultured from abdominal subcutaneous fat tissues of four metabolically healthy, lean female patients. After 7 weeks of culture, cellular responses to osteogenic differentiation media were examined. To evaluate the osteogenic potentials of undifferentiated adipose-derived stem cells and ceiling culture-derived preadipocytes, two types of epigenetic assessment were performed using next-generation sequencing: DNA methylation assays with the Human Methylation 450K BeadChip, and chromatin immunoprecipitation assays for trimethylation of histone H3 at lysine 4. RESULTS Human ceiling culture-derived preadipocytes showed greater osteogenic differentiation ability than did adipose-derived stem cells. In an epigenetic survey of the promoters of four osteogenic regulator genes (RUNX2, SP7, ATF4, and BGLAP), the authors found a general trend toward decreased CpG methylation and increased trimethylation of histone H3 at lysine 4 levels in ceiling culture-derived preadipocytes as compared to adipose-derived stem cells, indicating that these genes were more likely to be highly expressed in ceiling culture-derived preadipocytes. CONCLUSIONS The surveyed epigenetic differences between adipose-derived stem cells and ceiling culture-derived preadipocytes were consistent with the observed differences in osteogenic potential. These results enhance the authors' understanding of these cells and will facilitate their further application in regenerative medicine.
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17
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Abnormal expression of miR-135b-5p in bone tissue of patients with osteoporosis and its role and mechanism in osteoporosis progression. Exp Ther Med 2019; 19:1042-1050. [PMID: 32010267 PMCID: PMC6966120 DOI: 10.3892/etm.2019.8278] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 11/08/2019] [Indexed: 02/07/2023] Open
Abstract
Osteoporosis (OP) is an age-related bone disease occurring worldwide. Osteoporotic fracture is one of the leading causes of disability and death in elderly patients. MicroRNAs (miRNAs/miRs) are key molecular regulatory factors in bone remodeling processes. The present study investigated the expression and mechanism of miR-135b-5p in patients with osteoporosis. The present results suggested that miR-135b-5p was upregulated in bone tissue fragments of patients with osteoporosis compared with the control patients. MC3T3-E1 cells were used to perform osteogenic differentiation induction. Reverse transcription-quantitative PCR and western blot assay were used to detect the mRNA and protein expression levels of the osteogenic markers osteocalcin (OC), Osterix and alkaline phosphatase (ALP). A specific kit was used for detecting ALP activity. The present results indicated that the mRNA expression levels of OC, Osterix and ALP significantly increased on the 7 and 14th day after osteogenic differentiation induction compared with the control group. Protein expression levels of OC, Osterix and ALP also increased on the 7 and 14th day after induction. ALP assay showed that ALP activity was significantly increased on the 7 and 14th day after induction. In addition, the present study found that miR-135b-5p was downregulated in MC3T3-E1 cells 7 and 14 days after osteogenic differentiation induction. The results of TargetScan analysis and dual luciferase reporter gene assay indicated that runt-related transcription factor 2 (RUNX2) was a direct target gene of miR-135b-5p. RUNX2 was upregulated in MC3T3-E1 cells on the 7 and 14th day after induction. Moreover, the present study found that compared with the osteogenic differentiation induction group, miR-135b-5p mimic significantly decreased OC, Osterix and ALP expression, and reduced ALP activity in MC3T3-E1 cells. However, these reductions were reversed following overexpression of RUNX2. The present results showed that miR-135b-5p mimic significantly reduced cell viability in MC3T3-E1 cells and induced cell apoptosis, and these effects were significantly reversed following RUNX2 overexpression. In summary, the present results suggested that miR-135-5p participated in the occurrence and development of osteoporosis via inhibition of osteogenic differentiation and osteoblast growth by targeting RUNX2. The present study suggested a novel potential target that may faciliate the treatment of osteoporosis, and further study is required to examine this possibility.
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18
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Yao W, Zhang H, Jiang X, Mehmood K, Iqbal M, Li A, Zhang J, Wang Y, Waqas M, Shen Y, Li J. Effect of Total Flavonoids of Rhizoma drynariae on Tibial Dyschondroplasia by Regulating BMP-2 and Runx2 Expression in Chickens. Front Pharmacol 2018; 9:1251. [PMID: 30450047 PMCID: PMC6224448 DOI: 10.3389/fphar.2018.01251] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 10/15/2018] [Indexed: 01/15/2023] Open
Abstract
Tibial dyschondroplasia (TD) is an abnormality of the growth cartilage that occurs in chickens and other rapidly growing avian species. This disease not only cause huge economic losses, but also greatly affects animal welfare. The total flavonoids of Rhizoma drynariae (TFRD) has been used to cure wide variety of diseases including bone fractures and osteoarthritis and osteoporosis. However, less information is available about the using of TFRD against the TD. The aim of this study was to determine the effect of TFRD on TD by regulating BMP-2 and Runx2 in chickens. A total of 200 birds were randomly divided into control, TD, TD recovery (TDR), and TFRD groups. All the groups were given standard diet with an addition of thiram (50 mg/kg) from days 3 to 7 in TD, TDR, and TFRD groups in order to induce TD in chickens. After the induction of TD, the birds of TFRD group were fed standard diet with the addition of TFRD at 20 mg/kg. Clinical results conveyed that TFRD can improve the growth performance of the TD chickens and recover normal activity, and it is more obvious than TDR. Gene expressions of BMP-2 and Runx2 were down-regulated during the development of the disease and were up-regulated obviously after TFRD treatment. In conclusion, TFRD not only decreased the mortality rate but also increased the growth performance of TD in chickens. In conclusion, TFRD plays important role in improving the growth performance, adjusting the relevant physiological indicators, and regulating BMP-2 and Runx2 in chickens.
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Affiliation(s)
- Wangyuan Yao
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Hui Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Xiong Jiang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,Hubei Three Gorges Polytechnic, Yichang, China
| | - Khalid Mehmood
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,University College of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Mujahid Iqbal
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Aoyun Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Jialu Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Yaping Wang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Muhammad Waqas
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,Faculty of Veterinary and Animal Sciences, The University of Poonch, Rawalakot, Pakistan
| | - Yaoqin Shen
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Jiakui Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China.,College of Animals Husbandry and Veterinary Medicine, Tibet Academy of Agricultural and Animal Husbandry University, Linzhi, China
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Zeng L, Wei J, Han D, Liu H, Liu Y, Zhao N, Sun S, Wang Y, Feng H. Functional analysis of novel RUNX2 mutations in cleidocranial dysplasia. Mutagenesis 2018; 32:437-443. [PMID: 28505335 DOI: 10.1093/mutage/gex012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Cleidocranial dysplasia (CCD) is a rare autosomal dominant skeletal disorder caused by mutation of runt-related transcription factor 2 (RUNX2) gene. The purpose of this study was to explore novel RUNX2 mutations in seven individuals with CCD and investigate the function of the mutant RUNX2 proteins. DNA samples were prepared from the peripheral blood of the CCD individuals, and then subjected to DNA sequencing. Conservation and secondary structure analysis were performed based on RUNX2 sequencing results. pEGFP-C1 plasmids containing GFP-tagged wild-type RUNX2 and three novel RUNX2 mutations expression cassettes were constructed, and then transfected into HEK293T cells. Cell fluorescence, luciferase assay and western blotting were used to analyse the subcellular distribution and function of the mutant RUNX2 proteins. Three novel mutations (R193G, 258fs, Y400X) were found in the seven CCD patients. Conservation and structure analysis show one novel mutation (R193G) in Runt domain and two novel mutations (258fs and Y400X) in PST domain of RUNX2. Western blotting confirmed that the 258fs and Y400X mutations produced truncated proteins. Fluorescence detection showed that the three novel mutants localised exclusively in the nucleus. However, luciferase assay indicated all mutants severely impaired the transactivation activities of RUNX2 on osteocalcin promoter. Our results broaden the spectrum of RUNX2 mutations in CCD individuals and demonstrated that loss of function in RUNX2 is responsible for CCD.
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Affiliation(s)
- Li Zeng
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Jiahui Wei
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Dong Han
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Haochen Liu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Yang Liu
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Na Zhao
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Shichen Sun
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Yixiang Wang
- Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, PR China
| | - Hailan Feng
- Department of Prosthodontics, Peking University School and Hospital of Stomatology, Beijing, PR China
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20
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Jin Y, Chen S, Li N, Liu Y, Cheng G, Zhang C, Wang S, Zhang J. Defect-related luminescent bur-like hydroxyapatite microspheres induced apoptosis of MC3T3-E1 cells by lysosomal and mitochondrial pathways. SCIENCE CHINA-LIFE SCIENCES 2018; 61:464-475. [PMID: 29623549 DOI: 10.1007/s11427-017-9258-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 12/20/2017] [Indexed: 12/27/2022]
Abstract
When orthopedic joints coated by hydroxyapatite (HA) were implanted in the human body, they release wear debris into the surrounding tissues. The generation and accumulation of wear particles will induce aseptic loosening. However, the potential bioeffect and mechanism of HA-coated orthopedic implants on bone cells are poorly understood. In this study, defect-related luminescent bur-like hydroxyapatite (BHA) microspheres with the average diameter of 7-9 μm which are comparable to that of the wear-debris particles from aseptically loosened HA implants or HA debris have been synthesized by hydrothermal synthesis and the MC3T3-E1 cells were set as a cells model to study the potential bioeffect and mechanism of BHA microspheres. The studies demonstrated that BHA microspheres could be taken into MC3T3-E1 cells via endocytosis involved in micropinocytosis- and clathrin-mediated endocytosis process, and exert cytotoxicity effect. BHA microspheres could induce the cell apoptosis by intracellular production of reactive oxygen species (ROS), which led to not only an increase in the permeability of lysosome and release of cathepsins B, but also mitochondrial dysfunction and DNA damage. Our results provide novel evidence to elucidate their toxicity mechanisms and might be helpful for more reasonable applications of HA-based orthopaedic implants in the future.
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Affiliation(s)
- Yi Jin
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China
- Medical College of Hebei University, Baoding, 071000, China
| | - Shizhu Chen
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China
| | - Nan Li
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China
| | - Yajing Liu
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China
| | - Gong Cheng
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China
| | - Cuimiao Zhang
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China
| | - Shuxiang Wang
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China.
| | - Jinchao Zhang
- College of Chemistry & Environmental Science, Chemical Biology Key Laboratory of Hebei Province, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding, 071002, China.
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Komori T. Runx2, an inducer of osteoblast and chondrocyte differentiation. Histochem Cell Biol 2018; 149:313-323. [DOI: 10.1007/s00418-018-1640-6] [Citation(s) in RCA: 231] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2018] [Indexed: 12/20/2022]
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22
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Wakitani S, Yokoi D, Hidaka Y, Nishino K. The differentially DNA-methylated region responsible for expression of runt-related transcription factor 2. J Vet Med Sci 2016; 79:230-237. [PMID: 27916785 PMCID: PMC5326923 DOI: 10.1292/jvms.16-0321] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Runt-related transcription factor 2 (Runx2) is essential for osteogenesis. This study aimes at identification of the genomic region differentially methylated in DNA for regulation of Runx2 expression. In the proximal promoter of mouse Runx2, DNA methylation was frequent at the region further than 3 kb relative to the transcription start site, in contrast to lower methylation status of the closer locus within 2 kb from the transcription start site. At the intermediate part, we identified a novel differentially methylated region in the Runx2 promoter region (Runx2-DMR): from -2.7 to -2.2 kb relative to the start site of Runx2 transcription in mice. In this region, the DNA methylation rate correlated negatively with Runx2 expression among mouse organs as well as among primary cultures of bone marrow from different dogs. Induction of mouse and dog mesenchymal-like cells into osteoblastic differentiation decreased the methylation rate of Runx2-DMR. Thus, in this study, we identified a novel genomic region in which DNA methylation status is related to Runx2 expression and detected demethylation of Runx2-DMR during osteoblastic differentiation in mouse and dog.
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Affiliation(s)
- Shoichi Wakitani
- Laboratory of Veterinary Biochemistry and Molecular Biology, Faculty of Agriculture, University of Miyazaki, 1-1 Gakuenkibanadai-nishi, Miyazaki 889-2192, Japan
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23
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Jaruga A, Hordyjewska E, Kandzierski G, Tylzanowski P. Cleidocranial dysplasia and RUNX2-clinical phenotype-genotype correlation. Clin Genet 2016; 90:393-402. [DOI: 10.1111/cge.12812] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 05/20/2016] [Accepted: 05/28/2016] [Indexed: 12/19/2022]
Affiliation(s)
- A. Jaruga
- Department of Biochemistry and Molecular Biology; Medical University; Lublin Poland
- Postgraduate School of Molecular Medicine; Warsaw Poland
| | - E. Hordyjewska
- Department of Biochemistry and Molecular Biology; Medical University; Lublin Poland
- Postgraduate School of Molecular Medicine; Warsaw Poland
| | - G. Kandzierski
- Children Orthopaedic and Rehabilitation Department; Medical University of Lublin; Lublin Poland
| | - P. Tylzanowski
- Department of Biochemistry and Molecular Biology; Medical University; Lublin Poland
- Laboratory for Developmental and Stem Cell Biology, Department of Development and Regeneration, Skeletal Biology and Engineering Research Centre; University of Leuven; Leuven Belgium
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Santa Maria C, Cheng Z, Li A, Wang J, Shoback D, Tu CL, Chang W. Interplay between CaSR and PTH1R signaling in skeletal development and osteoanabolism. Semin Cell Dev Biol 2016; 49:11-23. [PMID: 26688334 PMCID: PMC4761456 DOI: 10.1016/j.semcdb.2015.12.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 12/05/2015] [Indexed: 12/01/2022]
Abstract
Parathyroid hormone (PTH)-related peptide (PTHrP) controls the pace of pre- and post-natal growth plate development by activating the PTH1R in chondrocytes, while PTH maintains mineral and skeletal homeostasis by modulating calciotropic activities in kidneys, gut, and bone. The extracellular calcium-sensing receptor (CaSR) is a member of family C, G protein-coupled receptor, which regulates mineral and skeletal homeostasis by controlling PTH secretion in parathyroid glands and Ca(2+) excretion in kidneys. Recent studies showed the expression of CaSR in chondrocytes, osteoblasts, and osteoclasts and confirmed its non-redundant roles in modulating the recruitment, proliferation, survival, and differentiation of the cells. This review emphasizes the actions of CaSR and PTH1R signaling responses in cartilage and bone and discusses how these two signaling cascades interact to control growth plate development and maintain skeletal metabolism in physiological and pathological conditions. Lastly, novel therapeutic regimens that exploit interrelationship between the CaSR and PTH1R are proposed to produce more robust osteoanabolism.
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Affiliation(s)
- Christian Santa Maria
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Zhiqiang Cheng
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Alfred Li
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Jiali Wang
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Dolores Shoback
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Chia-Ling Tu
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Wenhan Chang
- Endocrine Research Unit, University of California, San Francisco, Veterans Affairs Medical Center, San Francisco, CA, USA.
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25
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LIAO YUXIANG, LV GUOHUA, WANG BING, KUANG LEI, WANG XIAOBIN. Imatinib promotes apoptosis of giant cell tumor cells by targeting microRNA-30a-mediated runt-related transcription factor 2. Mol Med Rep 2015; 13:1739-45. [DOI: 10.3892/mmr.2015.4722] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 09/25/2015] [Indexed: 11/06/2022] Open
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26
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Rojas A, Aguilar R, Henriquez B, Lian JB, Stein JL, Stein GS, van Wijnen AJ, van Zundert B, Allende ML, Montecino M. Epigenetic Control of the Bone-master Runx2 Gene during Osteoblast-lineage Commitment by the Histone Demethylase JARID1B/KDM5B. J Biol Chem 2015; 290:28329-28342. [PMID: 26453309 DOI: 10.1074/jbc.m115.657825] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Indexed: 12/30/2022] Open
Abstract
Transcription factor Runx2 controls bone development and osteoblast differentiation by regulating expression of a significant number of bone-related target genes. Here, we report that transcriptional activation and repression of the Runx2 gene via its osteoblast-specific P1 promoter (encoding mRNA for the Runx2/p57 isoform) is accompanied by selective deposition and elimination of histone marks during differentiation of mesenchymal cells to the osteogenic and myoblastic lineages. These epigenetic profiles are mediated by key components of the Trithorax/COMPASS-like and Polycomb group complexes together with histone arginine methylases like PRMT5 and lysine demethylases like JARID1B/KDM5B. Importantly, knockdown of the H3K4me2/3 demethylase JARID1B, but not of the demethylases UTX and NO66, prevents repression of the Runx2 P1 promoter during myogenic differentiation of mesenchymal cells. The epigenetically forced expression of Runx2/p57 and osteocalcin, a classical bone-related target gene, under myoblastic-differentiation is accompanied by enrichment of the H3K4me3 and H3K27ac marks at the Runx2 P1 promoter region. Our results identify JARID1B as a key component of a potent epigenetic switch that controls mesenchymal cell fate into myogenic and osteogenic lineages.
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Affiliation(s)
- Adriana Rojas
- Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago, 8370146, Chile; Faculty of Sciences, Universidad de Chile, Santiago, 7800003, Chile; FONDAP Center for Genome Regulation, Santiago, Chile
| | - Rodrigo Aguilar
- Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago, 8370146, Chile; FONDAP Center for Genome Regulation, Santiago, Chile
| | - Berta Henriquez
- Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago, 8370146, Chile
| | - Jane B Lian
- University of Vermont Medical School, Burlington, Vermont 05405
| | - Janet L Stein
- University of Vermont Medical School, Burlington, Vermont 05405
| | - Gary S Stein
- University of Vermont Medical School, Burlington, Vermont 05405
| | | | - Brigitte van Zundert
- Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago, 8370146, Chile
| | - Miguel L Allende
- Faculty of Sciences, Universidad de Chile, Santiago, 7800003, Chile; FONDAP Center for Genome Regulation, Santiago, Chile
| | - Martin Montecino
- Center for Biomedical Research, Faculty of Biological Sciences and Faculty of Medicine, Universidad Andres Bello, Santiago, 8370146, Chile; FONDAP Center for Genome Regulation, Santiago, Chile.
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27
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Nagatake T, Fukuyama S, Sato S, Okura H, Tachibana M, Taniuchi I, Ito K, Shimojou M, Matsumoto N, Suzuki H, Kunisawa J, Kiyono H. Central Role of Core Binding Factor β2 in Mucosa-Associated Lymphoid Tissue Organogenesis in Mouse. PLoS One 2015; 10:e0127460. [PMID: 26001080 PMCID: PMC4441428 DOI: 10.1371/journal.pone.0127460] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 04/15/2015] [Indexed: 12/21/2022] Open
Abstract
Mucosa-associated lymphoid tissue (MALT) is a group of secondary and organized lymphoid tissue that develops at different mucosal surfaces. Peyer's patches (PPs), nasopharynx-associated lymphoid tissue (NALT), and tear duct-associated lymphoid tissue (TALT) are representative MALT in the small intestine, nasal cavity, and lacrimal sac, respectively. A recent study has shown that transcriptional regulators of core binding factor (Cbf) β2 and promotor-1-transcribed Runt-related transcription factor 1 (P1-Runx1) are required for the differentiation of CD3-CD4+CD45+ lymphoid tissue inducer (LTi) cells, which initiate and trigger the developmental program of PPs, but the involvement of this pathway in NALT and TALT development remains to be elucidated. Here we report that Cbfβ2 plays an essential role in NALT and TALT development by regulating LTi cell trafficking to the NALT and TALT anlagens. Cbfβ2 was expressed in LTi cells in all three types of MALT examined. Indeed, similar to the previous finding for PPs, we found that Cbfβ2-/- mice lacked NALT and TALT lymphoid structures. However, in contrast to PPs, NALT and TALT developed normally in the absence of P1-Runx1 or other Runx family members such as Runx2 and Runx3. LTi cells for NALT and TALT differentiated normally but did not accumulate in the respective lymphoid tissue anlagens in Cbfβ2-/- mice. These findings demonstrate that Cbfβ2 is a central regulator of the MALT developmental program, but the dependency of Runx proteins on the lymphoid tissue development would differ among PPs, NALT, and TALT.
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Affiliation(s)
- Takahiro Nagatake
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
- Laboratory of Vaccine Materials, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-asagi, Ibaraki-city, Osaka, 567–0085, Japan
| | - Satoshi Fukuyama
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
- Division of Virology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
| | - Shintaro Sato
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
| | - Hideaki Okura
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
| | - Masashi Tachibana
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences (IMS-RCAI), 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, 230–0045, Japan
| | - Ichiro Taniuchi
- Laboratory for Transcriptional Regulation, RIKEN Center for Integrative Medical Sciences (IMS-RCAI), 1-7-22, Suehiro-cho, Tsurumi-ku, Yokohama, 230–0045, Japan
| | - Kosei Ito
- Department of Molecular Bone Biology, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, 852–8588, Japan
| | - Michiko Shimojou
- Laboratory of Vaccine Materials, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-asagi, Ibaraki-city, Osaka, 567–0085, Japan
| | - Naomi Matsumoto
- Laboratory of Vaccine Materials, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-asagi, Ibaraki-city, Osaka, 567–0085, Japan
| | - Hidehiko Suzuki
- Laboratory of Vaccine Materials, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-asagi, Ibaraki-city, Osaka, 567–0085, Japan
| | - Jun Kunisawa
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
- Laboratory of Vaccine Materials, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-asagi, Ibaraki-city, Osaka, 567–0085, Japan
- International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Graduate School of Pharmaceutical Sciences, Osaka University, Osaka, Japan
- Department of Microbiology and Immunology, Kobe University School of Medicine, Kobe, Japan
| | - Hiroshi Kiyono
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108–8639, Japan
- International Research and Development Center for Mucosal Vaccines, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- Department of Medical Genome Science, Graduate School of Frontier Science, The University of Tokyo, Chiba, Japan
- * E-mail:
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Someya H, Fujiwara H, Nagata K, Wada H, Hasegawa K, Mikami Y, Jinno A, Sakai H, Koyano K, Kiyoshima T. Thymosin beta 4 is associated with RUNX2 expression through the Smad and Akt signaling pathways in mouse dental epithelial cells. Int J Mol Med 2015; 35:1169-78. [PMID: 25739055 PMCID: PMC4380193 DOI: 10.3892/ijmm.2015.2118] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 02/19/2015] [Indexed: 01/09/2023] Open
Abstract
In previous studies by our group, we reported that thymosin beta 4 (Tb4) is closely associated with the initiation and development of the tooth germ, and can induce the expression of runt-related transcription factor 2 (RUNX2) during the development of the tooth germ. RUNX2 regulates the expression of odontogenesis-related genes, such as amelogenin, X-linked (Amelx), ameloblastin (Ambn) and enamelin (Enam), as well as the differentiation of osteoblasts during bone formation. However, the mechanisms through which Tb4 induces the expression of RUNX2 remain unknown. In the present study, we employed a mouse dental epithelial cell line, mDE6, with the aim to elucidate these mechanisms. The mDE6 cells expressed odontogenesis-related genes, such as Runx2, Amelx, Ambn and Enam, and formed calcified matrices upon the induction of calcification, thus showing characteristics of odontogenic epithelial cells. The expression of odontogenesis-related genes, and the calcification of the mDE6 cells were reduced by the inhibition of phosphorylated Smad1/5 (p-Smad1/5) and phosphorylated Akt (p-Akt) proteins. Furthermore, we used siRNA against Tb4 to determine whether RUNX2 expression and calcification are associated with Tb4 expression in the mDE6 cells. The protein expression of p-Smad1/5 and p-Akt in the mDE6 cells was reduced by treatment with Tb4-siRNA. These results suggest that Tb4 is associated with RUNX2 expression through the Smad and PI3K-Akt signaling pathways, and with calcification through RUNX2 expression in the mDE6 cells. This study provides putative information concerning the signaling pathway through which Tb4 induces RUNX2 expression, which may help to understand the regulation of tooth development and tooth regeneration.
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Affiliation(s)
- Hirotaka Someya
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Hiroaki Fujiwara
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Kengo Nagata
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Hiroko Wada
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Kana Hasegawa
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Yurie Mikami
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Akiko Jinno
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Hidetaka Sakai
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Kiyoshi Koyano
- Section of Implant and Rehabilitative Dentistry, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
| | - Tamotsu Kiyoshima
- Laboratory of Oral Pathology, Division of Maxillofacial Diagnostic and Surgical Sciences, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582, Japan
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Xiao Z, Cao L, Liang Y, Huang J, Stern AR, Dallas M, Johnson M, Quarles LD. Osteoblast-specific deletion of Pkd2 leads to low-turnover osteopenia and reduced bone marrow adiposity. PLoS One 2014; 9:e114198. [PMID: 25464512 PMCID: PMC4252138 DOI: 10.1371/journal.pone.0114198] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 11/04/2014] [Indexed: 11/18/2022] Open
Abstract
Polycystin-1 (Pkd1) interacts with polycystin-2 (Pkd2) to form an interdependent signaling complex. Selective deletion of Pkd1 in the osteoblast lineage reciprocally regulates osteoblastogenesis and adipogenesis. The role of Pkd2 in skeletal development has not been defined. To this end, we conditionally inactivated Pkd2 in mature osteoblasts by crossing Osteocalcin (Oc)-Cre;Pkd2+/null mice with floxed Pkd2 (Pkd2flox/flox) mice. Oc-Cre;Pkd2flox/null (Pkd2Oc-cKO) mice exhibited decreased bone mineral density, trabecular bone volume, cortical thickness, mineral apposition rate and impaired biomechanical properties of bone. Pkd2 deficiency resulted in diminished Runt-related transcription factor 2 (Runx2) expressions in bone and impaired osteoblastic differentiation ex vivo. Expression of osteoblast-related genes, including, Osteocalcin, Osteopontin, Bone sialoprotein (Bsp), Phosphate-regulating gene with homologies to endopeptidases on the X chromosome (Phex), Dentin matrix protein 1 (Dmp1), Sclerostin (Sost), and Fibroblast growth factor 23 (FGF23) were reduced proportionate to the reduction of Pkd2 gene dose in bone of Oc-Cre;Pkd2flox/+ and Oc-Cre;Pkd2flox/null mice. Loss of Pkd2 also resulted in diminished peroxisome proliferator-activated receptor γ (PPARγ) expression and reduced bone marrow fat in vivo and reduced adipogenesis in osteoblast culture ex vivo. Transcriptional co-activator with PDZ-binding motif (TAZ) and Yes-associated protein (YAP), reciprocally acting as co-activators and co-repressors of Runx2 and PPARγ, were decreased in bone of Oc-Cre;Pkd2flox/null mice. Thus, Pkd1 and Pkd2 have coordinate effects on osteoblast differentiation and opposite effects on adipogenesis, suggesting that Pkd1 and Pkd2 signaling pathways can have independent effects on mesenchymal lineage commitment in bone.
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Affiliation(s)
- Zhousheng Xiao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, 38165, United States of America
| | - Li Cao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, 38165, United States of America
| | - Yingjuan Liang
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, 38165, United States of America
| | - Jinsong Huang
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, 38165, United States of America
| | - Amber Rath Stern
- Department of Oral Biology, School of Dentistry, University of Missouri-Kansas City, Kansas City, Missouri, 64108, United States of America
- Engineering Systems, Inc., Charlotte, North Carolina, 28227, United States of America
| | - Mark Dallas
- Department of Oral Biology, School of Dentistry, University of Missouri-Kansas City, Kansas City, Missouri, 64108, United States of America
| | - Mark Johnson
- Department of Oral Biology, School of Dentistry, University of Missouri-Kansas City, Kansas City, Missouri, 64108, United States of America
| | - Leigh Darryl Quarles
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, 38165, United States of America
- * E-mail:
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Okura H, Sato S, Kishikawa S, Kaneto S, Nakashima T, Yoshida N, Takayanagi H, Kiyono H. Runx2-I isoform contributes to fetal bone formation even in the absence of specific N-terminal amino acids. PLoS One 2014; 9:e108294. [PMID: 25244033 PMCID: PMC4171521 DOI: 10.1371/journal.pone.0108294] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Accepted: 08/25/2014] [Indexed: 01/03/2023] Open
Abstract
The Runt-related transcription factor 2 (Runx2) gene encodes the transcription factor Runx2, which is the master regulator of osteoblast development; insufficiency of this protein causes disorders of bone development such as cleidocranial dysplasia. Runx2 has two isoforms, Runx2-II and Runx2-I, and production of each isoform is controlled by a unique promoter: a distal promoter (P1) and a proximal promoter (P2), respectively. Although several studies have focused on differences and similarities between the two Runx2 isoforms, their individual roles in bone formation have not yet been determined conclusively, partly because a Runx2-I-targeted mouse model is not available. In this study, we established a novel Runx2-manipulated mouse model in which the first ATG of Runx2-I was replaced with TGA (a stop codon), and a neomycin-resistant gene (neo) cassette was inserted at the first intron of Runx2-I. Homozygous Runx2-Ineo/neo mice showed severely reduced expression of Runx2-I, whereas Runx2-II expression was largely retained. Runx2-Ineo/neo mice showed neonatal lethality, and in these mice, intramembranous ossification was more severely defective than endochondral ossification, presumably because of the greater involvement of Runx2-I, compared with that of Runx2-II in intramembranous ossification. Interestingly, the depletion of neo rescued the above-described phenotypes, indicating that the isoform-specific N-terminal region of Runx2-I is not functionally essential for bone development. Taken together, our results provide a novel clue leading to a better understanding of the roles of Runx2 isoforms in osteoblast development.
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Affiliation(s)
- Hideaki Okura
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; Department of Medical Genome Science, Graduate School of Frontier Science, The University of Tokyo, Chiba, Japan
| | - Shintaro Sato
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
| | - Sari Kishikawa
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Satoshi Kaneto
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Tomoki Nakashima
- Department of Cell Signaling, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Nobuaki Yoshida
- Laboratory of Developmental Genetics, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Takayanagi
- Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Kiyono
- Division of Mucosal Immunology, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan; Department of Medical Genome Science, Graduate School of Frontier Science, The University of Tokyo, Chiba, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Tokyo, Japan
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Abstract
Increases in fibroblastic growth factor 23 (FGF23 or Fgf23) production by osteocytes result in hypophosphatemia and rickets in the Hyp mouse homologue of X-linked hypophosphatemia (XLH). Fibroblastic growth factor (FGF) signaling has been implicated in the pathogenesis of Hyp. Here, we conditionally deleted FGF receptor 1 (FGFR1 or Fgfr1) in osteocytes of Hyp mice to investigate the role of autocrine/paracrine FGFR signaling in regulating FGF23 production by osteocytes. Crossing dentin matrix protein 1 (Dmp1)-Cre;Fgfr1null/+ mice with female Hyp;Fgfr1flox/flox mice created Hyp and Fgfr1 (Fgfr1Dmp1-cKO)-null mice (Hyp;Fgfr1Dmp1-cKO) with a 70% decrease in bone Fgfr1 transcripts. Fgfr1Dmp1-cKO-null mice exhibited a 50% reduction in FGF23 expression in bone and 3-fold reduction in serum FGF23 concentrations, as well as reductions in sclerostin (Sost), phosphate regulating endopeptidase on X chromosome (PHEX or Phex), matrix extracellular phosphoglycoprotein (Mepe), and Dmp1 transcripts, but had no demonstrable alterations in phosphate or vitamin D homeostasis or skeletal morphology. Hyp mice had hypophosphatemia, reductions in 1,25(OH)2D levels, rickets/osteomalacia and elevated FGF2 expression in bone. Compared to Hyp mice, compound Hyp;Fgfr1Dmp1-cKO-null mice had significant improvement in rickets and osteomalacia in association with a decrease in serum FGF23 (3607 to 1099 pg/ml), an increase in serum phosphate (6.0 mg/dl to 9.3 mg/dl) and 1,25(OH)2D (121±23 to 192±34 pg/ml) levels, but only a 30% reduction in bone FGF23 mRNA expression. FGF23 promoter activity in osteoblasts was stimulated by FGFR1 activation and inhibited by overexpression of a dominant negative FGFR1(TK−), PLCγ and MAPK inhibitors. FGF2 also stimulated the translation of an FGF23 cDNA transfected into osteoblasts via a FGFR1 and PI3K/Akt-dependent mechanism. Thus, activation of autocrine/paracrine FGF pathways is involved in the pathogenesis of Hyp through FGFR1-dependent regulation of FGF23 by both transcriptional and post-transcriptional mechanisms. This may serve to link local bone metabolism with systemic phosphate and vitamin D homeostasis.
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Tian F, Wu M, Deng L, Zhu G, Ma J, Gao B, Wang L, Li YP, Chen W. Core binding factor beta (Cbfβ) controls the balance of chondrocyte proliferation and differentiation by upregulating Indian hedgehog (Ihh) expression and inhibiting parathyroid hormone-related protein receptor (PPR) expression in postnatal cartilage and bone formation. J Bone Miner Res 2014; 29:1564-1574. [PMID: 24821091 PMCID: PMC4644666 DOI: 10.1002/jbmr.2275] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 12/24/2013] [Accepted: 05/12/2014] [Indexed: 12/20/2022]
Abstract
Core binding factor beta (Cbfβ) is essential for embryonic bone morphogenesis. Yet the mechanisms by which Cbfβ regulates chondrocyte proliferation and differentiation as well as postnatal cartilage and bone formation remain unclear. Hence, using paired-related homeobox transcription factor 1-Cre (Prx1-Cre) mice, mesenchymal stem cell-specific Cbfβ-deficient (Cbfβ(f/f) Prx1-Cre) mice were generated to study the role of Cbfβ in postnatal cartilage and bone development. These mutant mice survived to adulthood but exhibited severe sternum and limb malformations. Sternum ossification was largely delayed in the Cbfβ(f/f) Prx1-Cre mice and the xiphoid process was noncalcified and enlarged. In newborn and 7-day-old Cbfβ(f/f) Prx1-Cre mice, the resting zone was dramatically elongated, the proliferation zone and hypertrophic zone of the growth plates were drastically shortened and disorganized, and trabecular bone formation was reduced. Moreover, in 1-month-old Cbfβ(f/f) Prx1-Cre mice, the growth plates were severely deformed and trabecular bone was almost absent. In addition, Cbfβ deficiency impaired intramembranous bone formation both in vivo and in vitro. Interestingly, although the expression of Indian hedgehog (Ihh) was largely reduced, the expression of parathyroid hormone-related protein (PTHrP) receptor (PPR) was dramatically increased in the Cbfβ(f/f) Prx1-Cre growth plate, indicating that that Cbfβ deficiency disrupted the Ihh-PTHrP negative regulatory loop. Chromatin immunoprecipitation (ChIP) analysis and promoter luciferase assay demonstrated that the Runx/Cbfβ complex binds putative Runx-binding sites of the Ihh promoter regions, and also the Runx/Cbfβ complex directly upregulates Ihh expression at the transcriptional level. Consistently, the expressions of Ihh target genes, including CyclinD1, Ptc, and Pthlh, were downregulated in Cbfβ-deficient chondrocytes. Taken together, our study reveals not only that Cbfβ is essential for chondrocyte proliferation and differentiation for the growth and maintenance of the skeleton in postnatal mice, but also that it functions in upregulating Ihh expression to promoter chondrocyte proliferation and osteoblast differentiation, and inhibiting PPR expression to enhance chondrocyte differentiation.
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Affiliation(s)
- Fei Tian
- Shanghai Institute of Traumatology and Orthopedics, Ruijin Hospital, Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
- Department of Pathology, University of Alabama at Birmingham, USA
| | - Mengrui Wu
- Department of Pathology, University of Alabama at Birmingham, USA
- Institute of Genetics, Life Science College, Zhejiang University, People’s Republic of China
| | - Lianfu Deng
- Shanghai Institute of Traumatology and Orthopedics, Ruijin Hospital, Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Guochun Zhu
- Department of Pathology, University of Alabama at Birmingham, USA
| | - Junqing Ma
- Department of Pathology, University of Alabama at Birmingham, USA
| | - Bo Gao
- Department of Pathology, University of Alabama at Birmingham, USA
| | - Lin Wang
- Institute of Stomatology, Nanjing Medical University, 140 Hangzhou Road, Nanjing, Jiangsu 210029, China. USA
| | - Yi-Ping Li
- Department of Pathology, University of Alabama at Birmingham, USA
| | - Wei Chen
- Department of Pathology, University of Alabama at Birmingham, USA
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Piirsoo A, Kasak L, Kauts ML, Loog M, Tints K, Uusen P, Neuman T, Piirsoo M. Protein kinase inhibitor SU6668 attenuates positive regulation of Gli proteins in cancer and multipotent progenitor cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:703-14. [PMID: 24418624 PMCID: PMC3946003 DOI: 10.1016/j.bbamcr.2014.01.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 12/18/2013] [Accepted: 01/02/2014] [Indexed: 11/16/2022]
Abstract
Observations that Glioma-associated transcription factors Gli1 and Gli2 (Gli1/2), executers of the Sonic Hedgehog (Shh) signaling pathway and targets of the Transforming Growth Factor β (TGF-β) signaling axis, are involved in numerous developmental and pathological processes unveil them as attractive pharmaceutical targets. Unc-51-like serine/threonine kinase Ulk3 has been suggested to play kinase activity dependent and independent roles in the control of Gli proteins in the context of the Shh signaling pathway. This study aimed at investigating whether the mechanism of generation of Gli1/2 transcriptional activators has similarities regardless of the signaling cascade evoking their activation. We also elucidate further the role of Ulk3 kinase in regulation of Gli1/2 proteins and examine SU6668 as an inhibitor of Ulk3 catalytic activity and a compound targeting Gli1/2 proteins in different cell-based experimental models. Here we demonstrate that Ulk3 is required not only for maintenance of basal levels of Gli1/2 proteins but also for TGF-β or Shh dependent activation of endogenous Gli1/2 proteins in human adipose tissue derived multipotent stromal cells (ASCs) and mouse immortalized progenitor cells, respectively. We show that cultured ASCs possess the functional Shh signaling axis and differentiate towards osteoblasts in response to Shh. Also, we demonstrate that similarly to Ulk3 RNAi, SU6668 prevents de novo expression of Gli1/2 proteins and antagonizes the Gli-dependent activation of the gene expression programs induced by either Shh or TGF-β. Our data suggest SU6668 as an efficient inhibitor of Ulk3 kinase allowing manipulation of the Gli-dependent transcriptional outcome. Ulk3 is involved in the maintenance of Gli1/2 expression. SU6668 prevents de novo expression of Gli1/2 proteins induced by Shh or TGF-β. SU6668 inhibits up-regulation of Gli1/2 proteins via Ulk3. Human ASCs differentiate towards osteoblasts in response to Shh.
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Affiliation(s)
- Alla Piirsoo
- Protobios LLC, Mäealuse 4, Tallinn 12618, Estonia; Cellin Technologies LLC, Mäealuse 4, Tallinn 12618, Estonia.
| | - Lagle Kasak
- Protobios LLC, Mäealuse 4, Tallinn 12618, Estonia; Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, Tallinn 12618, Estonia
| | | | - Mart Loog
- Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Kairit Tints
- Cellin Technologies LLC, Mäealuse 4, Tallinn 12618, Estonia
| | - Piia Uusen
- Cellin Technologies LLC, Mäealuse 4, Tallinn 12618, Estonia
| | | | - Marko Piirsoo
- Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, Tallinn 12618, Estonia
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Morrison NA, Stephens AS, Osato M, Pasco JA, Fozzard N, Stein GS, Polly P, Griffiths LR, Nicholson GC. Polyalanine repeat polymorphism in RUNX2 is associated with site-specific fracture in post-menopausal females. PLoS One 2013; 8:e72740. [PMID: 24086263 PMCID: PMC3781152 DOI: 10.1371/journal.pone.0072740] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 07/12/2013] [Indexed: 12/29/2022] Open
Abstract
Runt related transcription factor 2 (RUNX2) is a key regulator of osteoblast differentiation. Several variations within the RUNX2 gene have been found to be associated with significant changes in BMD, which is a major risk factor for fracture. In this study we report that an 18 bp deletion within the polyalanine tract (17A>11A) of RUNX2 is significantly associated with fracture. Carriers of the 11A allele were found to be nearly twice as likely to have sustained fracture. Within the fracture category, there was a significant tendency of 11A carriers to present with fractures of distal radius and bones of intramembranous origin compared to bones of endochondral origin (p = 0.0001). In a population of random subjects, the 11A allele was associated with decreased levels of serum collagen cross links (CTx, p = 0.01), suggesting decreased bone turnover. The transactivation function of the 11A allele showed a minor quantitative decrease. Interestingly, we found no effect of the 11A allele on BMD at multiple skeletal sites. These findings suggest that the 11A allele is a biologically relevant polymorphism that influences serum CTx and confers enhanced fracture risk in a site-selective manner related to intramembranous bone ossification.
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Affiliation(s)
- Nigel A. Morrison
- School of Medical Sciences, Griffith University, Gold Coast, Queensland, Australia
- * E-mail:
| | | | - Motomi Osato
- Centre for Translational Medicine, Cancer Science Institute, National University of Singapore, Singapore, Singapore
| | - Julie A. Pasco
- School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Nicolette Fozzard
- School of Medical Sciences, Griffith University, Gold Coast, Queensland, Australia
| | - Gary S. Stein
- Vermont Cancer Center for Basic and Translational Research, University of Vermont, Burlington, Vermont, United States of America
| | - Patsie Polly
- Department of Pathology and Inflammation and Infection Research Centre, School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Lyn R. Griffiths
- School of Medical Sciences, Griffith University, Gold Coast, Queensland, Australia
| | - Geoff C. Nicholson
- Rural Clinical School, School of Medicine, The University of Queensland, Toowoomba, Queensland, Australia
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35
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Kammerer M, Gutzwiller S, Stauffer D, Delhon I, Seltenmeyer Y, Fournier B. Estrogen Receptor α (ERα) and Estrogen Related Receptor α (ERRα) are both transcriptional regulators of the Runx2-I isoform. Mol Cell Endocrinol 2013; 369:150-60. [PMID: 23403054 DOI: 10.1016/j.mce.2013.01.024] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 01/09/2013] [Accepted: 01/29/2013] [Indexed: 01/18/2023]
Abstract
Runx2 is a master regulator of bone development and has also been described as an oncogene. Estrogen Receptor α (ERα) and Estrogen Related Receptor α (ERRα), both implicated in bone metabolism and breast cancer, have been shown to share common transcriptional targets. Here, we show that ERα is a positive regulator of Runx2-I transcription. Moreover, ERRα can act as a transcriptional activator of Runx2-I in presence of peroxisome proliferator activated receptor gamma coactivator-1 alpha (PGC-1α). In contrast, ERRα behaves as a negative regulator of Runx2-I transcription in presence of PGC-1β. ERα and ERRα cross-talk via a common estrogen receptor response element on the Runx2-I promoter. In addition, estrogen regulates PGC-1β that in turn is able to modulate both ERα and ERRα transcriptional activity.
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Affiliation(s)
- Martial Kammerer
- Novartis Institutes for BioMedical Research, Musculoskeletal Disease Unit, CH-4002 Basel, Switzerland
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36
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Qiu N, Xiao Z, Cao L, David V, Quarles LD. Conditional mesenchymal disruption of pkd1 results in osteopenia and polycystic kidney disease. PLoS One 2012; 7:e46038. [PMID: 23029375 PMCID: PMC3448720 DOI: 10.1371/journal.pone.0046038] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 08/28/2012] [Indexed: 01/13/2023] Open
Abstract
Conditional deletion of Pkd1 in osteoblasts using either Osteocalcin(Oc)-Cre or Dmp1-Cre results in defective osteoblast-mediated postnatal bone formation and osteopenia. Pkd1 is also expressed in undifferentiated mesenchyme that gives rise to the osteoblast lineage. To examine the effects of Pkd1 on prenatal osteoblast development, we crossed Pkd1flox/flox and Col1a1(3.6)-Cre mice, which has been used to achieve selective inactivation of Pkd1 earlier in the osteoblast lineage. Control Pkd1flox/flox and Pkd1flox/+, heterozygous Col1a1(3.6)-Cre;Pkd1flox/+ and Pkd1flox/null, and homozygous Col1a1(3.6)-Cre;Pkd1flox/flox and Col1a1(3.6)-Cre;Pkd1flox/null mice were analyzed at ages ranging from E14.5 to 8-weeks-old. Newborn Col1a1(3.6)-Cre;Pkd1flox/null mice exhibited defective skeletogenesis in association with a greater reduction in Pkd1 expression in bone. Conditional Col1a1(3.6)-Cre;Pkd1flox/+ and Col1a1(3.6)-Cre;Pkd1flox/flox mice displayed a gene dose-dependent decrease in bone formation and increase in marrow fat at 6 weeks of age. Bone marrow stromal cell and primary osteoblast cultures from homozygous Col1a1(3.6)-Cre;Pkd1flox/flox mice showed increased proliferation, impaired osteoblast development and enhanced adipogenesis ex vivo. Unexpectedly, we found evidence for Col1a1(3.6)-Cre mediated deletion of Pkd1 in extraskeletal tissues in Col1a1(3.6)-Cre;Pkd1flox/flox mice. Deletion of Pkd1 in mesenchymal precursors resulted in pancreatic and renal, but not hepatic, cyst formation. The non-lethality of Col1a1(3.6)-Cre;Pkd1flox/flox mice establishes a new model to study abnormalities in bone development and cyst formation in pancreas and kidney caused by Pkd1 gene inactivation.
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Affiliation(s)
- Ni Qiu
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Zhousheng Xiao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Li Cao
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Valentin David
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Leigh Darryl Quarles
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- * E-mail:
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37
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Qiu N, Zhou H, Xiao Z. Downregulation of PKD1 by shRNA results in defective osteogenic differentiation via cAMP/PKA pathway in human MG-63 cells. J Cell Biochem 2012; 113:967-76. [PMID: 22034075 DOI: 10.1002/jcb.23426] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Mutations and/or deletions of Pkd1 in mouse models resulted in attenuation of osteoblast function and defective bone formation; however, the function of PKD1 in human osteoblast and bone remains uncertain. In the current study, we used lentivirus-mediated shRNA technology to stably knock down PKD1 in the human osteoblastic MG-63 cell line and to investigate the role of PKD1 on human osteoblast function and molecular mechanisms. We found that a 53% reduction of PKD1 by PKD1 shRNA in stable, transfected MG-63 cells resulted in increased cell proliferation and impaired osteoblastic differentiation as reflected by increased BrdU incorporation, decreased alkaline phosphatase activity, and calcium deposition and by decreased expression of RUNX2 and OSTERIX compared to control shRNA MG-63 cells. In addition, knockdown of PKD1 mRNA caused enhanced adipogenesis in stable PKD1 shRNA MG-63 cells as evidenced by elevated lipid accumulation and increased expression of adipocyte-related markers such as PPARγ and aP2. The stable PKD1 shRNA MG-63 cells exhibited lower basal intracellular calcium, which led to attenuated cytosolic calcium signaling in response to fluid flow shear stress, as well as increased intracellular cAMP messages in response to forskolin (10 µM) stimulation. Moreover, increased cell proliferation, inhibited osteoblastic differentiation, and osteogenic and adipogenic gene markers were significantly reversed in stable PKD1 shRNA MG-63 cells when treated with H89 (1 µM), an inhibitor of PKA. These findings suggest that downregulation of PKD1 in human MG-63 cells resulted in defective osteoblast function via intracellular calcium-cAMP/PKA signaling pathway.
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Affiliation(s)
- Ni Qiu
- Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, 410078, China
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38
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Zhang YY, Li X, Qian SW, Guo L, Huang HY, He Q, Liu Y, Ma CG, Tang QQ. Down-regulation of type I Runx2 mediated by dexamethasone is required for 3T3-L1 adipogenesis. Mol Endocrinol 2012; 26:798-808. [PMID: 22422618 DOI: 10.1210/me.2011-1287] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Runx2, a runt-related transcriptional factor family member, is involved in the regulation of osteoblast differentiation. Interestingly, it is abundant in growth-arrested 3T3-L1 preadipocytes and was dramatically down-regulated during adipocyte differentiation. Knockdown of Runx2 expression promoted 3T3-L1 adipocyte differentiation, whereas overexpression inhibited adipocyte differentiation and promoted the trans-differentiation of 3T3-L1 preadipocytes to bone cells. Runx2 was down-regulated specifically by dexamethasone (DEX). Only type I Runx2 was expressed in 3T3-L1 preadipocytes. Using luciferase assay and chromatin immunoprecipitation-quantitative PCR analysis, it was found that DEX repressed this type of Runx2 at the transcriptional level through direct binding of the glucocorticoid receptor (GR) to a GR-binding element in the Runx2 P2 promoter. Further studies indicated that GR recruited histone deacetylase 1 to the Runx2 P2 promoter which then mediated the deacetylation of histone H4 and down-regulated Runx2 expression. Runx2 might play its repressive role through the induction of p27 expression, which blocked 3T3-L1 adipocyte differentiation by inhibiting mitotic clonal expansion. Taken together, we identified Runx2 as a new downstream target of DEX and explored a new pathway between DEX, Runx2, and p27 which contributed to the mechanism of the 3T3-L1 adipocyte differentiation.
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Affiliation(s)
- You-you Zhang
- Key Laboratory of Molecular Medicine, the Ministry of Education; Department of Biochemistry and Molecular Biology, Fudan University Shanghai Medical College, Shanghai 200032, PR China
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39
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Qiu N, Xiao Z, Cao L, Buechel MM, David V, Roan E, Quarles LD. Disruption of Kif3a in osteoblasts results in defective bone formation and osteopenia. J Cell Sci 2012; 125:1945-57. [PMID: 22357948 DOI: 10.1242/jcs.095893] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We investigated whether Kif3a in osteoblasts has a direct role in regulating postnatal bone formation. We conditionally deleted Kif3a in osteoblasts by crossing osteocalcin (Oc; also known as Bglap)-Cre with Kif3a(flox/null) mice. Conditional Kif3a-null mice (Kif3a(Oc-cKO)) had a 75% reduction in Kif3a transcripts in bone and osteoblasts. Conditional deletion of Kif3a resulted in the reduction of primary cilia number by 51% and length by 27% in osteoblasts. Kif3a(Oc-cKO) mice developed osteopenia by 6 weeks of age unlike Kif3a(flox/+) control mice, as evidenced by reductions in femoral bone mineral density (22%), trabecular bone volume (42%) and cortical thickness (17%). By contrast, Oc-Cre;Kif3a(flox/+) and Kif3a(flox/null) heterozygous mice exhibited no skeletal abnormalities. Loss of bone mass in Kif3a(Oc-cKO) mice was associated with impaired osteoblast function in vivo, as reflected by a 54% reduction in mineral apposition rate and decreased expression of Runx2, osterix (also known as Sp7 transcription factor 7; Sp7), osteocalcin and Dmp1 compared with controls. Immortalized osteoblasts from Kif3a(Oc-cKO) mice exhibited increased cell proliferation, impaired osteoblastic differentiation, and enhanced adipogenesis in vitro. Osteoblasts derived from Kif3a(Oc-cKO) mice also had lower basal cytosolic calcium levels and impaired intracellular calcium responses to fluid flow shear stress. Sonic hedgehog-mediated Gli2 expression and Wnt3a-mediated β-catenin and Axin2 expression were also attenuated in Kif3a(Oc-cKO) bone and osteoblast cultures. These data indicate that selective deletion of Kif3a in osteoblasts disrupts primary cilia formation and/or function and impairs osteoblast-mediated bone formation through multiple pathways including intracellular calcium, hedgehog and Wnt signaling.
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Affiliation(s)
- Ni Qiu
- Department of Medicine, the University of Tennessee Health Science Center, Memphis, TN 38165, USA
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40
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Liang B, Cotter MM, Chen D, Hernandez CJ, Zhou G. Ectopic expression of SOX9 in osteoblasts alters bone mechanical properties. Calcif Tissue Int 2012; 90:76-89. [PMID: 22143895 PMCID: PMC3272153 DOI: 10.1007/s00223-011-9550-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 11/11/2011] [Indexed: 12/28/2022]
Abstract
Osteoporosis is a common skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. We previously demonstrated that Col1a1-SOX9 transgenic (TG) mice, in which SOX9 specifically expresses in osteoblasts driven by a 2.3-kb Col1a1 promoter, display osteopenia during the early postnatal stage. In this study, to further analyze the osteopenia phenotype and especially the effect of the osteoblast-specific expression of SOX9 on bone mechanical properties, we performed bone geometry and mechanical property analysis of long bones from Col1a1-SOX9 TG mice and wild-type littermates (WT) at different time points. Interestingly, after body weight adjustment, TG mice had similar whole-bone strength as WT mice but significantly thinner cortical bone, lower elastic modulus, and higher moment of inertia. Thus, osteoblast-specific SOX9 expression results in altered bone structure and material properties. Furthermore, the expression levels of Pcna, Col1a1, osteocalcin, and the Opg/Rankl ratio in TG mice were significantly lower until 4 months of age compared with WT mice, suggesting that TG mice have dysregulated bone homeostasis. Finally, bone marrow stromal cells (MSCs) isolated from TG mice display enhanced adipocyte differentiation and decreased osteoblast differentiation in vitro, suggesting that osteoblast-specific expression of SOX9 can lead to altered mesenchymal stem cell differentiation potentials. In conclusion, our study implies that SOX9 activity has to be tightly regulated in the adult skeleton to ensure optimal bone quality.
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Affiliation(s)
- Bojian Liang
- Department of Orthopaedics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, U. S. A
| | - Meghan M. Cotter
- Department of Anatomy, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, U. S. A
| | - Dongxing Chen
- Department of Orthopaedics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, U. S. A
| | - Christopher J. Hernandez
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, U.S.A
| | - Guang Zhou
- Department of Orthopaedics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, U. S. A
- Department of Genetics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, U. S. A
- Case Comprehensive Cancer Center, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, U. S. A
- Corresponding author: Guang Zhou, Ph.D., Department of Orthopaedics, BRB, Room 328, Case Western Reserve University, 2109 Adelbert Road, Cleveland, OH 44106, U. S. A., Tel: (216) 368-2260, Fax: (216) 368-1332,
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Doetschman T, Barnett JV, Runyan RB, Camenisch TD, Heimark RL, Granzier HL, Conway SJ, Azhar M. Transforming growth factor beta signaling in adult cardiovascular diseases and repair. Cell Tissue Res 2011; 347:203-23. [PMID: 21953136 DOI: 10.1007/s00441-011-1241-3] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 09/02/2011] [Indexed: 01/15/2023]
Abstract
The majority of children with congenital heart disease now live into adulthood due to the remarkable surgical and medical advances that have taken place over the past half century. Because of this, adults now represent the largest age group with adult cardiovascular diseases. It includes patients with heart diseases that were not detected or not treated during childhood, those whose defects were surgically corrected but now need revision due to maladaptive responses to the procedure, those with exercise problems and those with age-related degenerative diseases. Because adult cardiovascular diseases in this population are relatively new, they are not well understood. It is therefore necessary to understand the molecular and physiological pathways involved if we are to improve treatments. Since there is a developmental basis to adult cardiovascular disease, transforming growth factor beta (TGFβ) signaling pathways that are essential for proper cardiovascular development may also play critical roles in the homeostatic, repair and stress response processes involved in adult cardiovascular diseases. Consequently, we have chosen to summarize the current information on a subset of TGFβ ligand and receptor genes and related effector genes that, when dysregulated, are known to lead to cardiovascular diseases and adult cardiovascular deficiencies and/or pathologies. A better understanding of the TGFβ signaling network in cardiovascular disease and repair will impact genetic and physiologic investigations of cardiovascular diseases in elderly patients and lead to an improvement in clinical interventions.
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Liu JC, Lengner CJ, Gaur T, Lou Y, Hussain S, Jones MD, Borodic B, Colby JL, Steinman HA, van Wijnen AJ, Stein JL, Jones SN, Stein GS, Lian JB. Runx2 protein expression utilizes the Runx2 P1 promoter to establish osteoprogenitor cell number for normal bone formation. J Biol Chem 2011; 286:30057-70. [PMID: 21676869 DOI: 10.1074/jbc.m111.241505] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Runt-related transcription factor, Runx2, is essential for osteogenesis and is controlled by both distal (P1) and proximal (P2) promoters. To understand Runx2 function requires determination of the spatiotemporal activity of P1 and P2 to Runx2 protein production. We generated a mouse model in which the P1-derived transcript was replaced with a lacZ reporter allele, resulting in loss of P1-derived protein while simultaneously allowing discrimination between the activities of the two promoters. Loss of P1-driven expression causes developmental defects with cleidocranial dysplasia-like syndromes that persist in the postnatal skeleton. P1 activity is robust in preosteogenic mesenchyme and at the onset of bone formation but decreases as bone matures. Homozygous Runx2-P1(lacZ/lacZ) mice have a normal life span but exhibit severe osteopenia and compromised bone repair in adult mice because of osteoblastic defects and not increased osteoclastic resorption. Gene expression profiles of bone, immunohistochemical studies, and ex vivo differentiation using calvarial osteoblasts and marrow stromal cells identified mechanisms for the skeletal phenotype. The findings indicate that P1 promoter activity is necessary for generating a threshold level of Runx2 protein to commit sufficient osteoprogenitor numbers for normal bone formation. P1 promoter function is not compensated via the P2 promoter. However, the P2 transcript with compensatory mechanisms from bone morphogenetic protein (BMP) and Wnt signaling is adequate for mineralization of the bone tissue that does form. We conclude that selective utilization of the P1 and P2 promoters enables the precise spatiotemporal expression of Runx2 necessary for normal skeletogenesis and the maintenance of bone mass in the adult.
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Affiliation(s)
- Julie C Liu
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
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He N, Xiao Z, Yin T, Stubbs J, Li L, Quarles LD. Inducible expression of Runx2 results in multiorgan abnormalities in mice. J Cell Biochem 2011; 112:653-65. [PMID: 21268087 DOI: 10.1002/jcb.22968] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Runx2 is a transcription factor controlling skeletal development, and is also expressed in extraskeletal tissues where its function is not well understood. Existing Runx2 mutant and transgenic mouse models do not allow the necessary control of Runx2 expression to understand its functions in different tissues. We generated conditional, doxycyline-inducible, triple transgenic mice (CMV-Cre;ROSA26-neo(flox/+)-rtTA;Tet-O-Runx2) to investigate the effects of wide spread overexpression of Runx2. Osteoblasts isolated from CMV-Cre;ROSA26-neo(flox/+)-rtTA; Tet-O-Runx2 mice demonstrated a dose-dependent effect of doxycycline to stimulate Runx2 transgene expression. Doxycycline administration to CMV-Cre;ROSA26-neo(flox/+)-rtTA;Tet-O-Runx2 mice induced Runx2 transgene expression in all tissues tested, with the highest levels observed in kidney, ovary, and bone. Runx2 overexpression resulted in deceased body size and reduced viability. With regard to bone, Runx2 overexpressing mice paradoxically displayed profound osteopenia and diminished osteogenesis. Induced expression of Runx2 in extraskeletal tissues resulted in ectopic calcification and induction of the osteogenic program in a limited number of tissues, including lung and muscle. In addition, the triple transgenic mice showed evidence of a myeloproliferative disorder and an apparent inhibition of lymphocyte development. Thus, overexpression of Runx2 both within and outside of the skeleton can have diverse biological effects. Use of tissue specific Cre mice will allow this model to be used to conditionally and inducibly overexpress Runx2 in different tissues and provide a means to study the post-natal tissue- and cell context-dependent functions of Runx2.
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Affiliation(s)
- Nan He
- The Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Xiao Z, Dallas M, Qiu N, Nicolella D, Cao L, Johnson M, Bonewald L, Quarles LD. Conditional deletion of Pkd1 in osteocytes disrupts skeletal mechanosensing in mice. FASEB J 2011; 25:2418-32. [PMID: 21454365 DOI: 10.1096/fj.10-180299] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We investigated whether polycystin-1 is a bone mechanosensor. We conditionally deleted Pkd1 in mature osteoblasts/osteocytes by crossing Dmp1-Cre with Pkd1(flox/m1Bei) mice, in which the m1Bei allele is nonfunctional. We assessed in wild-type and Pkd1-deficient mice the response to mechanical loading in vivo by ulna loading and ex vivo by measuring the response of isolated osteoblasts to fluid shear stress. We found that conditional Pkd1 heterozygotes (Dmp1-Cre;Pkd1(flox/+)) and null mice (Pkd1(Dmp1-cKO)) exhibited a ∼ 40 and ∼ 90% decrease, respectively, in functional Pkd1 transcripts in bone. Femoral bone mineral density (12 vs. 27%), trabecular bone volume (32 vs. 48%), and cortical thickness (6 vs. 17%) were reduced proportionate to the reduction of Pkd1 gene dose, as were mineral apposition rate (MAR) and expression of Runx2-II, Osteocalcin, Dmp1, and Phex. Anabolic load-induced periosteal lamellar MAR (0.58 ± 0.14; Pkd1(Dmp1-cKO) vs. 1.68 ± 0.34 μm/d; control) and increases in Cox-2, c-Jun, Wnt10b, Axin2, and Runx2-II gene expression were significantly attenuated in Pkd1(Dmp1-cKO) mice compared with controls. Application of fluid shear stress to immortalized osteoblasts from Pkd1(null/null) and Pkd1(m1Bei/m1Bei)-derived osteoblasts failed to elicit the increments in cytosolic calcium observed in wild-type controls. These data indicate that polycystin-1 is essential for the anabolic response to skeletal loading in osteoblasts/osteocytes.
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Affiliation(s)
- Zhousheng Xiao
- Department of Medicine, The University of Tennessee Health Science Center, Memphis, TN 38165, USA.
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Qiu N, Cao L, David V, Quarles LD, Xiao Z. Kif3a deficiency reverses the skeletal abnormalities in Pkd1 deficient mice by restoring the balance between osteogenesis and adipogenesis. PLoS One 2010; 5:e15240. [PMID: 21151991 PMCID: PMC2996304 DOI: 10.1371/journal.pone.0015240] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Accepted: 11/02/2010] [Indexed: 11/18/2022] Open
Abstract
Pkd1 localizes to primary cilia in osteoblasts and osteocytes. Targeted deletion of Pkd1 in osteoblasts results in osteopenia and abnormalities in Runx2-mediated osteoblast development. Kif3a, an intraflagellar transport protein required for cilia function, is also expressed in osteoblasts. To assess the relationship between Pkd1 and primary cilia function on bone development, we crossed heterozygous Pkd1- and Kif3a-deficient mice to create compound Pkd1 and Kif3a-deficient mice. Pkd1 haploinsufficiency (Pkd1(+/Δ)) resulted in osteopenia, characterized by decreased bone mineral density, trabecular bone volume, and cortical thickness. In addition, deficiency of Pkd1 resulted in impaired osteoblastic differentiation and enhanced adipogenesis in both primary osteoblasts and/or bone marrow stromal cell cultures. These changes were associated with decreased Runx2 expression, increased PPARγ expression, and impaired hedgehog signaling as evidenced by decreased Gli2 expression in bone and osteoblast cultures. In contrast, heterozygous Kif3a(+/Δ) mice display no abnormalities in skeletal development or osteoblast function, but exhibited decreased adipogenic markers in bone and impaired adipogenesis in vitro in association with decreased PPARγ expression and upregulation of Gli2. Superimposed Kif3a deficiency onto Pkd1(+/Δ) mice paradoxically corrected the effects of Pkd1 deficiency on bone mass, osteoblastic differentiation, and adipogenesis. In addition, Runx2, PPARγ and Gli2 expression in bone and osteoblasts were normalized in compound double Pkd1(+/Δ) and Kif3a(+/Δ) heterozygous mice. The administration of sonic hedgehog, overexpression of Gli2, and the PC1 C-tail construct all increased Gli2 and Runx2-II expression, but decreased PPARγ2 gene expression in C3H10T1/2 cells. Our findings suggest a role for Pkd1 and Kif3a to counterbalance the regulation of osteogenesis and adipogenesis through differential regulation of Runx2 and PPARγ by Gli2.
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Affiliation(s)
- Ni Qiu
- Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, China
- Division of Nephrology, Department of Medicine, the University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Li Cao
- Division of Nephrology, Department of Medicine, the University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Valentin David
- Division of Nephrology, Department of Medicine, the University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - L. Darryl Quarles
- Division of Nephrology, Department of Medicine, the University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Zhousheng Xiao
- Division of Nephrology, Department of Medicine, the University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
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Challen GA, Goodell MA. Runx1 isoforms show differential expression patterns during hematopoietic development but have similar functional effects in adult hematopoietic stem cells. Exp Hematol 2010; 38:403-16. [PMID: 20206228 DOI: 10.1016/j.exphem.2010.02.011] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Revised: 02/25/2010] [Accepted: 02/25/2010] [Indexed: 12/27/2022]
Abstract
OBJECTIVE RUNX1 (also known as acute myeloid leukemia 1) is an essential regulator of hematopoiesis and has multiple isoforms arising from differential splicing and utilization of two promoters. We hypothesized that the rare Runx1c isoform has a distinct role in hematopoietic stem cells (HSCs). MATERIALS AND METHODS We have characterized the expression pattern of Runx1c in mouse embryos and human embryonic stem cell (hESC)-derived embryoid bodies using in situ hybridization and expression levels in mouse and human HSCs by real-time polymerase chain reaction. We then determined the functional effects of Runx1c using enforced retroviral overexpression in mouse HSCs. RESULTS We observed differential expression profiles of RUNX1 isoforms during hematopoietic differentiation of hESCs. The RUNX1a and RUNX1b isoforms were expressed consistently throughout hematopoietic differentiation, whereas the RUNX1c isoform was only expressed at the time of emergence of definitive HSCs. RUNX1c was also expressed in the AGM region of E10.5 to E11.5 mouse embryos, the region where definitive HSCs arise. These observations suggested that the RUNX1c isoform may be important for the specification or function of definitive HSCs. However, using retroviral overexpression to study the effect of RUNX1 isoforms on HSCs in a gain-of-function system, no discernable functional difference could be identified between RUNX1 isoforms in mouse HSCs. Overexpression of both RUNX1b and RUNX1c induced quiescence in mouse HSCs in vitro and in vivo. CONCLUSIONS Although the divergent expression profiles of Runx1 isoforms during development suggest specific roles for these proteins at different stages of HSC maturation, we could not detect an important functional distinction in adult mouse HSCs using our assay systems.
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Affiliation(s)
- Grant A Challen
- Stem Cells and Regenerative Medicine Center, Baylor College of Medicine, Houston, Tex. 77030, USA
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Zhu H, Bendall AJ. Dlx5 Is a cell autonomous regulator of chondrocyte hypertrophy in mice and functionally substitutes for Dlx6 during endochondral ossification. PLoS One 2009; 4:e8097. [PMID: 19956613 PMCID: PMC2779492 DOI: 10.1371/journal.pone.0008097] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Accepted: 11/04/2009] [Indexed: 01/18/2023] Open
Abstract
The axial and appendicular skeleton of vertebrates develops by endochondral ossification, in which skeletogenic tissue is initially cartilaginous and the differentiation of chondrocytes via the hypertrophic pathway precedes the differentiation of osteoblasts and the deposition of a definitive bone matrix. Results from both loss-of-function and misexpression studies have implicated the related homeobox genes Dlx5 and Dlx6 as partially redundant positive regulators of chondrocyte hypertrophy. However, experimental perturbations of Dlx expression have either not been cell type specific or have been done in the context of endogenous Dlx5 expression. Thus, it has not been possible to conclude whether the effects on chondrocyte differentiation are cell autonomous or whether they are mediated by Dlx expression in adjacent tissues, notably the perichondrium. To address this question we first engineered transgenic mice in which Dlx5 expression was specifically restricted to immature and differentiating chondrocytes and not the perichondrium. Col2a1-Dlx5 transgenic embryos and neonates displayed accelerated chondrocyte hypertrophy and mineralization throughout the endochondral skeleton. Furthermore, this transgene specifically rescued defects of chondrocyte differentiation characteristic of the Dlx5/6 null phenotype. Based on these results, we conclude that the role of Dlx5 in the hypertrophic pathway is cell autonomous. We further conclude that Dlx5 and Dlx6 are functionally equivalent in the endochondral skeleton, in that the requirement for Dlx5 and Dlx6 function during chondrocyte hypertrophy can be satisfied with Dlx5 alone.
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Affiliation(s)
- Hui Zhu
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Andrew J. Bendall
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
- * E-mail:
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Xiao Z, Zhang S, Cao L, Qiu N, David V, Quarles LD. Conditional disruption of Pkd1 in osteoblasts results in osteopenia due to direct impairment of bone formation. J Biol Chem 2009; 285:1177-87. [PMID: 19887454 DOI: 10.1074/jbc.m109.050906] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
PKD1 (polycystin-1), the disease-causing gene for ADPKD, is widely expressed in various cell types, including osteoblasts, where its function is unknown. Although global inactivation of Pkd1 in mice results in abnormal skeletal development, the presence of polycystic kidneys and perinatal lethality confound ascertaining the direct osteoblastic functions of PKD1 in adult bone. To determine the role of PKD1 in osteoblasts, we conditionally inactivated Pkd1 in postnatal mature osteoblasts by crossing Oc (osteocalcin)-Cre mice with floxed Pkd1 (Pkd1(flox/m1Bei)) mice to generate conditional heterozygous (Oc-Cre;Pkd1(flox/+)) and homozygous (Oc-Cre;Pkd1(flox/m1Bei)) Pkd1-deficient mice. Cre-mediated recombination (Pkd1(Delta flox)) occurred exclusively in bone. Compared with control mice, the conditional deletion of Pkd1 from osteoblasts resulted in a gene dose-dependent reduction in bone mineral density, trabecular bone volume, and cortical thickness. In addition, mineral apposition rates and osteoblast-related gene expression, including Runx2-II (Runt-related transcription factor 2), osteocalcin, osteopontin, and bone sialoprotein, were reduced proportionate to the reduction of Pkd1 gene dose in bone of Oc-Cre;Pkd1(flox/+) and Oc-Cre;Pkd1(flox/m1Bei) mice. Primary osteoblasts derived from Oc-Cre;Pkd1(flox/m1Bei) displayed impaired differentiation and suppressed activity of the phosphatidylinositol 3-kinase-Akt-GSK3beta-beta-catenin signaling pathways. The conditional deletion of Pkd1 also resulted in increased adipogenesis in bone marrow and in osteoblast cultures. Thus, PKD1 directly functions in osteoblasts to regulate bone formation.
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Affiliation(s)
- Zhousheng Xiao
- Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas 66160, USA
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Abstract
Runx2 controls the commitment of mesenchymal cells to the osteoblastic lineage. Distinct promoters, designated P1 and P2, give rise to functionally similar Runx2-II and Runx2-I isoforms. We postulate that this dual promoter gene structure permits temporal and spatial adjustments in the amount of Runx2 isoforms necessary for optimal bone development. To evaluate the gene dose-dependent effect of Runx2 isoforms on bone development, we intercrossed selective Runx2-II(+/-) with nonselective Runx2-II(+/-)/Runx2-I(+/-) mice to create compound mutant mice: Runx2-II(+/-), Runx2-II(+/-)/Runx2-I(+/-), Runx2-II(-/-), Runx2-II(-/-)/Runx2-I(+/-), Runx2-II(-/-)/Runx2-I(-/-). Analysis of the different Runx2-deficient genotypes showed gene dose-dependent differences in the level of expression of the Runx2 isoforms. In addition, we found that Runx2-I is predominately expressed in the perichondrium and proliferating chondrocytes, whereas Runx2-II is expressed in hypertrophic chondrocytes and metaphyseal osteoblasts. Newborn mice showed impaired development of a mineralized skeleton, bone length, and widening of the hypertrophic zone that were proportionate to the reduction in total Runx2 protein expression. Osteoblast differentiation ex vivo was also proportionate to total amount of Runx2 expression that correlated with reduced Runx2 binding to the osteocalcin promoter by quantitative chromatin immunoprecipitation analysis. Functional analysis of P1 and P2 promoters showed differential regulation of the two promoters in osteoblastic cell lines. These findings support the possibility that the total amount of Runx2 derived from two isoforms and the P1 and P2 promoters, by regulating the time, place, and amount of Runx2 in response to changing environmental cues, impacts on bone development.
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Abstract
OBJECTIVE Mutations in the RUNX2 gene, a master regulator of bone formation, have been identified in cleidocranial dysplasia (CCD) patients. CCD is a rare autosomal-dominant disease characterized by the delayed closure of cranial sutures, defects in clavicle formation, and supernumerary teeth. The purposes of this study were to identify genetic causes of two CCD nuclear families and to report their clinical phenotypes. MATERIALS AND METHODS We identified two CCD nuclear families and performed mutational analyses to clarify the underlying molecular genetic etiology. RESULTS Mutational analysis revealed a novel nonsense mutation (c.273T>A, p.L93X) in family 1 and a de novo missense one (c.673C>T, p.R225W) in family 2. Individuals with a nonsense mutation showed maxillary hypoplasia, delayed eruption, multiple supernumerary teeth, and normal stature. In contrast, an individual with a de novo missense mutation in the Runt domain showed only one supernumerary tooth and short stature. CONCLUSIONS Mutational and phenotypic analyses showed that the severity of mutations on the skeletal system may not necessarily correlate with that of the disruption of tooth development.
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Affiliation(s)
- H-M Ryoo
- Department of Cell and Developmental Biology, Dental Research Institute and BK21 Program, School of Dentistry, Seoul National University, Seoul 110-768, Korea
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