1
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Perrin S, Protic S, Bretegnier V, Laurendeau I, de Lageneste OD, Panara N, Ruckebusch O, Luka M, Masson C, Maillard T, Coulpier F, Pannier S, Wicart P, Hadj-Rabia S, Radomska KJ, Zarhrate M, Ménager M, Vidaud D, Topilko P, Parfait B, Colnot C. MEK-SHP2 inhibition prevents tibial pseudarthrosis caused by NF1 loss in Schwann cells and skeletal stem/progenitor cells. Sci Transl Med 2024; 16:eadj1597. [PMID: 38924432 DOI: 10.1126/scitranslmed.adj1597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 01/15/2024] [Accepted: 05/24/2024] [Indexed: 06/28/2024]
Abstract
Congenital pseudarthrosis of the tibia (CPT) is a severe pathology marked by spontaneous bone fractures that fail to heal, leading to fibrous nonunion. Half of patients with CPT are affected by the multisystemic genetic disorder neurofibromatosis type 1 (NF1) caused by mutations in the NF1 tumor suppressor gene, a negative regulator of RAS-mitogen-activated protein kinase (MAPK) signaling pathway. Here, we analyzed patients with CPT and Prss56-Nf1 knockout mice to elucidate the pathogenic mechanisms of CPT-related fibrous nonunion and explored a pharmacological approach to treat CPT. We identified NF1-deficient Schwann cells and skeletal stem/progenitor cells (SSPCs) in pathological periosteum as affected cell types driving fibrosis. Whereas NF1-deficient SSPCs adopted a fibrotic fate, NF1-deficient Schwann cells produced critical paracrine factors including transforming growth factor-β and induced fibrotic differentiation of wild-type SSPCs. To counteract the elevated RAS-MAPK signaling in both NF1-deficient Schwann cells and SSPCs, we used MAPK kinase (MEK) and Src homology 2 containing protein tyrosine phosphatase 2 (SHP2) inhibitors. Combined MEK-SHP2 inhibition in vivo prevented fibrous nonunion in the Prss56-Nf1 knockout mouse model, providing a promising therapeutic strategy for the treatment of fibrous nonunion in CPT.
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Affiliation(s)
- Simon Perrin
- Université Paris Est Creteil, INSERM, IMRB, 94000 Creteil, France
| | - Sanela Protic
- Université Paris Est Creteil, INSERM, IMRB, 94000 Creteil, France
| | | | - Ingrid Laurendeau
- INSERM UMR S1016, Institut Cochin, Université Paris Cité, 75014 Paris, France
| | | | - Nicolas Panara
- INSERM UMR S1016, Institut Cochin, Université Paris Cité, 75014 Paris, France
| | - Odile Ruckebusch
- Université Paris Est Creteil, INSERM, IMRB, Plateforme de Cytométrie en flux, 94000 Creteil, France
| | - Marine Luka
- Paris Cité University, Imagine Institute, Laboratory of Inflammatory Responses and Transcriptomic Networks in Diseases, Atip-Avenir Team, INSERM UMR 1163, 75015 Paris, France
- Labtech Single-Cell@Imagine, Imagine Institute, INSERM UMR 1163, 75015 Paris, France
| | - Cécile Masson
- Bioinformatics Core Facility, Institut Imagine-Structure Fédérative de Recherche Necker, INSERM U1163, 75015 Paris, France
- INSERM US24/CNRS UAR3633, Paris Cité University, 75015 Paris, France
| | - Théodora Maillard
- Service de Médecine Génomique des Maladies de Système et d'Organe, Hôpital Cochin, DMU BioPhyGen, Assistance Publique-Hôpitaux de Paris, AP-HP, Centre-Université Paris Cité, F-75014 Paris, France
| | - Fanny Coulpier
- Université Paris Est Creteil, INSERM, IMRB, 94000 Creteil, France
| | - Stéphanie Pannier
- Department of Pediatric Orthopedic Surgery and Traumatology, Necker-Enfants Malades Hospital, AP-HP, Paris Cité University, 75015 Paris, France
| | - Philippe Wicart
- Department of Pediatric Orthopedic Surgery and Traumatology, Necker-Enfants Malades Hospital, AP-HP, Paris Cité University, 75015 Paris, France
| | - Smail Hadj-Rabia
- Department of Dermatology, Reference Center for Rare Skin Diseases (MAGEC), Imagine Institute, Necker-Enfants Malades Hospital, AP-HP, Paris Cité University, 75015 Paris, France
| | | | - Mohammed Zarhrate
- INSERM US24/CNRS UAR3633, Paris Cité University, 75015 Paris, France
- Genomics Core Facility, Institut Imagine-Structure Fédérative de Recherche Necker, INSERM U1163, 75015 Paris, France
| | - Mickael Ménager
- Paris Cité University, Imagine Institute, Laboratory of Inflammatory Responses and Transcriptomic Networks in Diseases, Atip-Avenir Team, INSERM UMR 1163, 75015 Paris, France
- Labtech Single-Cell@Imagine, Imagine Institute, INSERM UMR 1163, 75015 Paris, France
| | - Dominique Vidaud
- INSERM UMR S1016, Institut Cochin, Université Paris Cité, 75014 Paris, France
- Service de Médecine Génomique des Maladies de Système et d'Organe, Hôpital Cochin, DMU BioPhyGen, Assistance Publique-Hôpitaux de Paris, AP-HP, Centre-Université Paris Cité, F-75014 Paris, France
| | - Piotr Topilko
- Université Paris Est Creteil, INSERM, IMRB, 94000 Creteil, France
| | - Béatrice Parfait
- INSERM UMR S1016, Institut Cochin, Université Paris Cité, 75014 Paris, France
- Service de Médecine Génomique des Maladies de Système et d'Organe, Hôpital Cochin, DMU BioPhyGen, Assistance Publique-Hôpitaux de Paris, AP-HP, Centre-Université Paris Cité, F-75014 Paris, France
| | - Céline Colnot
- Université Paris Est Creteil, INSERM, IMRB, 94000 Creteil, France
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2
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Ahmed R, Uppuganti S, Derasari S, Meyer J, Pennings JS, Elefteriou F, Nyman JS. Identifying Bone Matrix Impairments in a Mouse Model of Neurofibromatosis Type 1 (NF1) by Clinically Translatable Techniques. J Bone Miner Res 2022; 37:1603-1621. [PMID: 35690920 PMCID: PMC9378557 DOI: 10.1002/jbmr.4633] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/25/2022] [Accepted: 06/04/2022] [Indexed: 11/06/2022]
Abstract
Three-to-four percent of children with neurofibromatosis type 1 (NF1) present with unilateral tibia bowing, fracture, and recalcitrant healing. Alkaline phosphatase (ALP) enzyme therapy prevented poor bone mineralization and poor mechanical properties in mouse models of NF1 skeletal dysplasia; but transition to clinical trials is hampered by the lack of a technique that (i) identifies NF1 patients at risk of tibia bowing and fracture making them eligible for trial enrollment and (ii) monitors treatment effects on matrix characteristics related to bone strength. Therefore, we assessed the ability of matrix-sensitive techniques to provide characteristics that differentiate between cortical bone from mice characterized by postnatal loss of Nf1 in Osx-creTet-Off ;Nf1flox/flox osteoprogenitors (cKO) and from wild-type (WT) mice. Following euthanasia at two time points of bone disease progression, femur and tibia were harvested from both genotypes (n ≥ 8/age/sex/genotype). A reduction in the mid-diaphysis ultimate force during three-point bending at 20 weeks confirmed deleterious changes in bone induced by Nf1 deficiency, regardless of sex. Pooling females and males, low bound water (BW), and low cortical volumetric bone mineral density (Ct.vBMD) were the most accurate outcomes in distinguishing cKO from WT femurs with accuracy improving with age. Ct.vBMD and the average unloading slope (Avg-US) from cyclic reference point indentation tests were the most sensitive in differentiating WT from cKO tibias. Mineral-to-matrix ratio and carbonate substitution from Raman spectroscopy were not good classifiers. However, when combined with Ct.vBMD and BW (femur), they helped predict bending strength. Nf1 deficiency in osteoprogenitors negatively affected bone microstructure and matrix quality with deficits in properties becoming more pronounced with duration of Nf1 deficiency. Clinically measurable without ionizing radiation, BW and Avg-US are sensitive to deleterious changes in bone matrix in a preclinical model of NF1 bone dysplasia and require further clinical investigation as potential indicators of an onset of bone weakness in children with NF1. © 2022 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Rafay Ahmed
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.,Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sasidhar Uppuganti
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.,Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Shrey Derasari
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Joshua Meyer
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Jacquelyn S Pennings
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.,Center for Musculoskeletal Research, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Florent Elefteriou
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA.,Department of Orthopaedic Surgery, Baylor College of Medicine, Houston, TX, USA
| | - Jeffry S Nyman
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.,Center for Bone Biology, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA.,Center for Musculoskeletal Research, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN, USA
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3
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Avolio E, Katare R, Thomas AC, Caporali A, Schwenke D, Carrabba M, Meloni M, Caputo M, Madeddu P. Cardiac pericyte reprogramming by MEK inhibition promotes arteriologenesis and angiogenesis of the ischemic heart. J Clin Invest 2022; 132:e152308. [PMID: 35349488 PMCID: PMC9106362 DOI: 10.1172/jci152308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 03/23/2022] [Indexed: 11/17/2022] Open
Abstract
Pericytes (PCs) are abundant yet remain the most enigmatic and ill-defined cell population in the heart. Here, we investigated whether PCs can be reprogrammed to aid neovascularization. Primary PCs from human and mouse hearts acquired cytoskeletal proteins typical of vascular smooth muscle cells (VSMCs) upon exclusion of EGF/bFGF, which signal through ERK1/2, or upon exposure to the MEK inhibitor PD0325901. Differentiated PCs became more proangiogenic, more responsive to vasoactive agents, and insensitive to chemoattractants. RNA sequencing revealed transcripts marking the PD0325901-induced transition into proangiogenic, stationary VSMC-like cells, including the unique expression of 2 angiogenesis-related markers, aquaporin 1 (AQP1) and cellular retinoic acid-binding protein 2 (CRABP2), which were further verified at the protein level. This enabled us to trace PCs during in vivo studies. In mice, implantation of Matrigel plugs containing human PCs plus PD0325901 promoted the formation of αSMA+ neovessels compared with PC only. Two-week oral administration of PD0325901 to mice increased the heart arteriolar density, total vascular area, arteriole coverage by PDGFRβ+AQP1+CRABP2+ PCs, and myocardial perfusion. Short-duration PD0325901 treatment of mice after myocardial infarction enhanced the peri-infarct vascularization, reduced the scar, and improved systolic function. In conclusion, myocardial PCs have intrinsic plasticity that can be pharmacologically modulated to promote reparative vascularization of the ischemic heart.
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Affiliation(s)
- Elisa Avolio
- Bristol Medical School, Translational Health Sciences, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Rajesh Katare
- Department of Physiology, HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Anita C. Thomas
- Bristol Medical School, Translational Health Sciences, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Andrea Caporali
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Daryl Schwenke
- Department of Physiology, HeartOtago, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Michele Carrabba
- Bristol Medical School, Translational Health Sciences, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Marco Meloni
- University/BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, United Kingdom
| | - Massimo Caputo
- Bristol Medical School, Translational Health Sciences, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
| | - Paolo Madeddu
- Bristol Medical School, Translational Health Sciences, and Bristol Heart Institute, University of Bristol, Bristol, United Kingdom
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4
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Harder A. MEK inhibitors - novel targeted therapies of neurofibromatosis associated benign and malignant lesions. Biomark Res 2021; 9:26. [PMID: 33863389 PMCID: PMC8052700 DOI: 10.1186/s40364-021-00281-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/30/2021] [Indexed: 12/18/2022] Open
Abstract
MAP/ERK kinase 1 and 2 (MEK 1/2) inhibitors (MEKi) are investigated in several trials to treat lesions that arise from pathogenic variants of the Neurofibromatosis type 1 and type 2 genes (NF1, NF2). These trials showed that MEKi are capable to shrink volume of low grade gliomas and plexiform neurofibromas in NF1. Targeting other lesions being associated with a high morbidity in NF1 seems to be promising. Due to involvement of multiple pathways in NF2 associated lesions as well as in malignant tumors, MEKi are also used in combination therapies. This review outlines the current state of MEKi application in neurofibromatosis and associated benign and malignant lesions.
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Affiliation(s)
- Anja Harder
- Institute of Pathology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 14, 06120, Halle (Saale), Germany. .,Institute of Neuropathology, University Hospital Münster, Münster, Germany. .,Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus - Senftenberg, the Brandenburg Medical School Theodor Fontane and the University of Potsdam, Potsdam, Germany.
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5
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Deo N, El-Hoss J, Kolind M, Mikulec K, Peacock L, Little DG, Schindeler A. JNK inhibitor CC-930 reduces fibrosis in a murine model of Nf1-deficient fracture repair. J Appl Biomed 2018. [DOI: 10.1016/j.jab.2018.01.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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6
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Abstract
INTRODUCTION Neurofibromatosis type 1 (NF1) is an autosomal dominantly inherited tumor predisposition syndrome with an incidence of one in 3000-4000 individuals with no currently effective therapies. The NF1 gene encodes neurofibromin, which functions as a negative regulator of RAS. NF1 is a chronic multisystem disorder affecting many different tissues. Due to cell-specific complexities of RAS signaling, therapeutic approaches for NF1 will likely have to focus on a particular tissue and manifestation of the disease. Areas covered: We discuss the multisystem nature of NF1 and the signaling pathways affected due to neurofibromin deficiency. We explore the cell-/tissue-specific molecular and cellular consequences of aberrant RAS signaling in NF1 and speculate on their potential as therapeutic targets for the disease. We discuss recent genomic, transcriptomic, and proteomic studies combined with molecular, cellular, and biochemical analyses which have identified several targets for specific NF1 manifestations. We also consider the possibility of patient-specific gene therapy approaches for NF1. Expert opinion: The emergence of NF1 genotype-phenotype correlations, characterization of cell-specific signaling pathways affected in NF1, identification of novel biomarkers, and the development of sophisticated animal models accurately reflecting human pathology will continue to provide opportunities to develop therapeutic approaches to combat this multisystem disorder.
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Affiliation(s)
- James A Walker
- a Center for Genomic Medicine , Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA
| | - Meena Upadhyaya
- b Division of Cancer and Genetics , Cardiff University , Cardiff , UK
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7
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Stevenson DA, Hanson H, Stevens A, Carey J, Viskochil D, Sheng X, Wheeler K, Slater H. Quantitative Ultrasound and Tibial Dysplasia in Neurofibromatosis Type 1. J Clin Densitom 2018; 21:179-184. [PMID: 28438404 DOI: 10.1016/j.jocd.2017.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Accepted: 03/23/2017] [Indexed: 01/14/2023]
Abstract
Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder associated with unilateral anterolateral bowing with subsequent fracture and nonunion. In infancy, physiologic bowing of the lower leg can be confused with pathologic tibial dysplasia in NF1. Little is known about the bone physiology of the tibiae prior to fracture or predictors of fracture. The aim of this study was to characterize bone quality of bowed tibiae prior to fracture in NF1 using quantitative ultrasound (QUS). Bone quality was assessed on both tibiae (the non-bowed and bowed tibiae) using QUS to measure speed of sound (SOS) at the mid-shaft in 23 individuals with NF1. SOS (m/s) was determined and Z-scores generated using cross-sectional reference data of the same sex and age. The mean difference in SOS Z-scores when comparing the bowed tibia vs the individual's contralateral unaffected tibia was statistically significant with lower mean Z-scores in the bowed tibia (p = 0.001). Radiographs of all individuals with a clinical diagnosis of anterolateral bowing were reviewed, and in 2 individuals the radiographs showed minimal bowing with absence of characteristic cortical thickening and medullary canal narrowing in NF1-related tibial dysplasia, suggesting physiologic bowing. In both individuals, the Z-scores of the bowed leg were not lower than the unaffected leg supporting the suggestion of physiologic bowing rather than pathologic tibial dysplasia. These data show that dysplastic tibiae in NF1 prior to fracture and nonunion have abnormal bone quality with significant decreases in SOS even though radiographically the tibiae show a thickened cortex. These data also suggest that QUS can help distinguish dysplastic bowing vs physiologic bowing in infancy in NF1. QUS is an effective quantitative outcome measure for trials aimed at improving tibial bowing to prevent fracture, and it is a potential aid in diagnosis and clinical management in NF1.
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Affiliation(s)
- David A Stevenson
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA; Department of Pediatrics, Division of Medical Genetics, Stanford University, Stanford, CA, USA.
| | - Heather Hanson
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Austin Stevens
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - John Carey
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - David Viskochil
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Xiaoming Sheng
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Karen Wheeler
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Hillarie Slater
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
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8
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Summers MA, Vasiljevski ER, Mikulec K, Peacock L, Little DG, Schindeler A. Developmental dosing with a MEK inhibitor (PD0325901) rescues myopathic features of the muscle-specific but not limb-specific Nf1 knockout mouse. Mol Genet Metab 2018; 123:518-525. [PMID: 29477258 DOI: 10.1016/j.ymgme.2018.02.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 02/15/2018] [Accepted: 02/15/2018] [Indexed: 12/11/2022]
Abstract
Neurofibromatosis Type 1 (NF1) is a common autosomal dominant genetic disorder While NF1 is primarily associated with predisposition for tumor formation, muscle weakness has emerged as having a significant impact on quality of life. NF1 inactivation is linked with a canonical upregulation Ras-MEK-ERK signaling. This in this study we tested the capacity of the small molecule MEK inhibitor PD0325901 to influence the intramyocellular lipid accumulation associated with NF1 deficiency. Established murine models of tissue specific Nf1 deletion in skeletal muscle (Nf1MyoD-/-) and limb mesenchyme (Nf1Prx1-/-) were tested. Developmental PD0325901 dosing of dams pregnant with Nf1MyoD-/- progeny rescued the phenotype of day 3 pups including body weight and lipid accumulation by Oil Red O staining. In contrast, PD0325901 treatment of 4 week old Nf1Prx1-/- mice for 8 weeks had no impact on body weight, muscle wet weight, activity, or intramyocellular lipid. Examination of day 3 Nf1Prx1-/- pups showed differences between the two tissue-specific knockout strains, with lipid staining greatest in Nf1MyoD-/- mice, and fibrosis higher in Nf1Prx1-/- mice. These data show that a MEK/ERK dependent mechanism underlies NF1 muscle metabolism during development. However, crosstalk from Nf1-deficient non-muscle mesenchymal cells may impact upon muscle metabolism and fibrosis in neonatal and mature myofibers.
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Affiliation(s)
- Matthew A Summers
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics & Child Heath, Faculty of Medicine, University of Sydney, Camperdown, NSW, Australia
| | - Emily R Vasiljevski
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics & Child Heath, Faculty of Medicine, University of Sydney, Camperdown, NSW, Australia
| | - Kathy Mikulec
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - Lauren Peacock
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - David G Little
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics & Child Heath, Faculty of Medicine, University of Sydney, Camperdown, NSW, Australia
| | - Aaron Schindeler
- Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Westmead, NSW, Australia; Discipline of Paediatrics & Child Heath, Faculty of Medicine, University of Sydney, Camperdown, NSW, Australia.
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9
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Deo N, Cheng TL, Mikulec K, Peacock L, Little DG, Schindeler A. Improved union and bone strength in a mouse model of NF1 pseudarthrosis treated with recombinant human bone morphogenetic protein-2 and zoledronic acid. J Orthop Res 2018; 36:930-936. [PMID: 28767180 DOI: 10.1002/jor.23672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 07/29/2017] [Indexed: 02/04/2023]
Abstract
Tibial pseudarthrosis associated with Neurofibromatosis type 1 (NF1) is an orthopedic condition with consistently poor clinical outcomes. Using a murine model that features localized double inactivation of the Nf1 gene in an experimental tibial fracture, we tested the effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) and/or the bisphosphonate zoledronic acid (ZA). Tibiae were harvested at 3 weeks for analysis, at which time there was negligible healing in un-treated control fractures (7% union). In contrast, rhBMP-2 and rhBMP-2/ZA groups showed significantly greater union (87% and 93%, p < 0.01 for both). Treatment with rhBMP-2 led to a 12-fold increase in callus bone volume and this was further increased in the rhBMP-2/ZA group. Mechanical testing of the healed rhBMP-2 and rhBMP-2/ZA fractures showed that the latter group had significantly higher mechanical strength and was restored to that of the un-fractured contralateral leg. Co-treatment with rhBMP-2/ZA also reduced fibrous tissue infiltration at the fracture site compared to rhBMP alone (p = 0.068). These data support the future clinical investigation of this combination of anabolic and anti-resorptive agents for the treatment of NF1 pseudarthrosis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:930-936, 2018.
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Affiliation(s)
- Nikita Deo
- Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, New South Wales, 2145, Australia.,Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, Sydney, Australia
| | - Tegan L Cheng
- Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, New South Wales, 2145, Australia.,Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, Sydney, Australia
| | - Kathy Mikulec
- Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, New South Wales, 2145, Australia
| | - Lauren Peacock
- Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, New South Wales, 2145, Australia
| | - David G Little
- Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, New South Wales, 2145, Australia.,Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, Sydney, Australia
| | - Aaron Schindeler
- Orthopaedic Research and Biotechnology Unit, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, New South Wales, 2145, Australia.,Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, Sydney, Australia
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10
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Zhang W, Chen E, Chen M, Ye C, Qi Y, Ding Q, Li H, Xue D, Gao X, Pan Z. IGFBP7 regulates the osteogenic differentiation of bone marrow-derived mesenchymal stem cells via Wnt/β-catenin signaling pathway. FASEB J 2018; 32:2280-2291. [PMID: 29242275 DOI: 10.1096/fj.201700998rr] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Insulin-like growth factor-binding protein 7 (IGFBP7), a low-affinity IGF binder, may play an important role in bone metabolism. However, its function in osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (BMSCs) remains unclear. Therefore, we investigated its effects on osteogenic differentiation. Overexpression of IGFBP7 enhanced the expression of osteo-specific genes and proteins, and IGFBP7 knockdown decreased osteogenesis-specific markers. More mineral deposits and higher alkaline phosphatase activity were observed after the up-regulation of IGFBP7. Moreover, β-catenin levels were up-regulated by the overexpression of IGFBP7 or the addition of extracellular IGFBP7 protein and were reduced by the depletion of IGFBP7. The increase in osteogenic differentiation due to the overexpression of IGFBP7 was partially decreased by specific Wnt/β-catenin signaling inhibitors. Using a rat tibial osteotomy model, a sheet of IGFBP7-overexpressing BMSCs improved bone healing, as demonstrated by imaging, biomechanical, and histologic analyses. Taken together, these findings indicate that IGFBP7 regulates the osteogenic differentiation of BMSCs partly via the Wnt/β-catenin signaling pathway.-Zhang, W., Chen, E., Chen, M., Ye, C., Qi, Y., Ding, Q., Li, H., Xue, D., Gao, X., Pan, Z. IGFBP7 regulates the osteogenic differentiation of bone marrow-derived mesenchymal stem cells via Wnt/β-catenin signaling pathway.
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Affiliation(s)
- Wei Zhang
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Erman Chen
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Mo Chen
- Department of Rheumatology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Department of Nephrology, Hangzhou Hospital of Traditional Chinese Medicine, Hangzhou, China
| | - Chenyi Ye
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Yiying Qi
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Qianhai Ding
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Hang Li
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Deting Xue
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Xiang Gao
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
| | - Zhijun Pan
- Department of Orthopedics, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China.,Research Institute of Orthopaedics, Zhejiang University, Hangzhou, China
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11
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Tahaei SE, Couasnay G, Ma Y, Paria N, Gu J, Lemoine BF, Wang X, Rios JJ, Elefteriou F. The reduced osteogenic potential of Nf1-deficient osteoprogenitors is EGFR-independent. Bone 2018; 106:103-111. [PMID: 29032173 PMCID: PMC5694354 DOI: 10.1016/j.bone.2017.10.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 09/28/2017] [Accepted: 10/10/2017] [Indexed: 12/26/2022]
Abstract
Neurofibromatosis type 1 (NF1) is a common genetic disorder caused by mutations in the NF1 gene. Recalcitrant bone healing following fracture (i.e. pseudarthrosis) is one of the most problematic skeletal complications associated with NF1. The etiology of this condition is still unclear; thus, pharmacological options for clinical management are limited. Multiple studies have shown the reduced osteogenic potential of Nf1-deficient osteoprogenitors. A recent transcriptome profiling investigation revealed that EREG and EGFR, encoding epiregulin and its receptor Epidermal Growth Factor Receptor 1, respectively, were among the top over-expressed genes in cells of the NF1 pseudarthrosis site. Because EGFR stimulation is known to inhibit osteogenic differentiation, we hypothesized that increased EREG and EGFR expression in NF1-deficient skeletal progenitors may contribute to their reduced osteogenic differentiation potential. In this study, we first confirmed via single-cell mRNA sequencing that EREG over-expression was associated with NF1 second hit somatic mutations in human bone cells, whereas Transforming Growth Factor beta 1 (TGFβ1) expression was unchanged. Second, using ex-vivo recombined Nf1-deficient mouse bone marrow stromal cells (mBMSCs), we show that this molecular signature is conserved between mice and humans, and that epiregulin generated by these cells is overexpressed and active, whereas soluble TGFβ1 expression and activity are not affected. However, blocking either epiregulin function or EGFR signaling by EGFR1 or pan EGFR inhibition (using AG-1478 and Poziotinib respectively) did not correct the differentiation defect of Nf1-deficient mBMSCs, as measured by the expression of Alpl, Ibsp and alkaline phosphatase activity. These results suggest that clinically available drugs aimed at inhibiting EGFR signaling are unlikely to have a significant benefit for the management of bone non-union in children with NF1 PA.
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Affiliation(s)
- S E Tahaei
- Department of Pharmacology, Vanderbilt University, Nashville, TN, United States; Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, United States
| | - G Couasnay
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, United States
| | - Y Ma
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, United States
| | - N Paria
- Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital for Children, Dallas, TX, United States
| | - J Gu
- Baylor Institute for Immunology Research, Dallas, TX, United States
| | - B F Lemoine
- Baylor Institute for Immunology Research, Dallas, TX, United States
| | - X Wang
- Baylor Institute for Immunology Research, Dallas, TX, United States
| | - J J Rios
- Seay Center for Musculoskeletal Research, Texas Scottish Rite Hospital for Children, Dallas, TX, United States; Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, United States; McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, United States; Department of Orthopaedic Surgery, UT Southwestern Medical Center, Dallas, TX, United States
| | - F Elefteriou
- Department of Orthopedic Surgery, Baylor College of Medicine, Houston, TX, United States; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States.
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12
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O’Donnell C, Foster J, Mooney R, Beebe C, Donaldson N, Heare T. Congenital Pseudarthrosis of the Tibia. JBJS Rev 2017; 5:e3. [DOI: 10.2106/jbjs.rvw.16.00068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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13
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Ghadakzadeh S, Kannu P, Whetstone H, Howard A, Alman BA. β‐Catenin modulation in neurofibromatosis type 1 bone repair: therapeutic implications. FASEB J 2016; 30:3227-37. [DOI: 10.1096/fj.201500190rr] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 05/31/2017] [Indexed: 12/12/2022]
Affiliation(s)
- Saber Ghadakzadeh
- Division of Developmental and Stem Cell BiologyUniversity of Toronto Toronto Ontario Canada
- Institute of Medical ScienceUniversity of Toronto Toronto Ontario Canada
| | - Peter Kannu
- Division of Developmental and Stem Cell BiologyUniversity of Toronto Toronto Ontario Canada
- Institute of Medical ScienceUniversity of Toronto Toronto Ontario Canada
- Bone Health CentreHospital for Sick Children Toronto Ontario Canada
| | - Heather Whetstone
- Division of Developmental and Stem Cell BiologyUniversity of Toronto Toronto Ontario Canada
| | - Andrew Howard
- Bone Health CentreHospital for Sick Children Toronto Ontario Canada
- Division of Orthopaedic SurgeryHospital for Sick Children Toronto Ontario Canada
| | - Benjamin A. Alman
- Division of Developmental and Stem Cell BiologyUniversity of Toronto Toronto Ontario Canada
- Institute of Medical ScienceUniversity of Toronto Toronto Ontario Canada
- Department of Orthopaedic SurgeryDuke University Durham North Carolina USA
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Overexpression of HSPA1A enhances the osteogenic differentiation of bone marrow mesenchymal stem cells via activation of the Wnt/β-catenin signaling pathway. Sci Rep 2016; 6:27622. [PMID: 27279016 PMCID: PMC4899801 DOI: 10.1038/srep27622] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/23/2016] [Indexed: 12/04/2022] Open
Abstract
HSPA1A, which encodes cognate heat shock protein 70, plays important roles in various cellular metabolic pathways. To investigate its effects on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), its expression level was compared between undifferentiated and differentiated BMSCs. Rat HSPA1A overexpression in BMSCs increased osteoblast-specific gene expression, alkaline phosphatase activity, and mineral deposition in vitro. Moreover, it upregulated β-catenin and downregulated DKK1 and SOST. The enhanced osteogenesis due to HSPA1A overexpression was partly rescued by a Wnt/β-catenin inhibitor. Additionally, using a rat tibial fracture model, a sheet of HSPA1A-overexpressing BMSCs improved bone fracture healing, as determined by imaging and histological analysis. Taken together, these findings suggest that HSPA1A overexpression enhances osteogenic differentiation of BMSCs, partly through Wnt/β-catenin.
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Rhodes SD, Yang FC. Aberrant Myeloid Differentiation Contributes to the Development of Osteoporosis in Neurofibromatosis Type 1. Curr Osteoporos Rep 2016; 14:10-5. [PMID: 26932441 DOI: 10.1007/s11914-016-0298-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neurofibromatosis type 1 (NF1), also known as von Recklinghausen disease, is a common autosomal dominant genetic disorder affecting approximately 1 in 3000 individuals worldwide. NF1 results from heritable or spontaneous mutations of the NF1 tumor suppressor gene. NF1 encodes the protein neurofibromin, which functions to negatively regulate Ras-activity. Approximately 50 % of NF1 patients develop osteopenia or osteoporosis, resulting in significantly increased rates of long-bone fracture and morbidity. While defective osteoblast bone anabolism has been implicated as a central factor in the pathogenesis of NF1 associated skeletal deficits, recent data suggest that NF1 (Nf1) haploinsufficiency within the hematopoietic compartment, particularly in osteoclasts and myeloid progenitors, plays a pivotal role in engendering NF1 osseous manifestations. In this chapter, we review the latest data from clinical studies and murine models delineating a critical role for hematopoietic compartment, myeloid progenitors of NF1 (Nf1) haploinsufficient and their progeny-osteoclasts, in the pathogenesis of NF1 associated osteopenia/osteoporosis and discuss putative targets for future therapeutics.
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Affiliation(s)
- Steven D Rhodes
- Department of Pediatrics, Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Feng-Chun Yang
- Sylvester Comprehensive Cancer Center, Department of Biochemistry and Molecular Biology, University of Miami School of Medicine, R. Bunn Gautier Building, 417 1011 NW 15th street, Locator R-629, Miami, FL, 33136, USA.
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16
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Capturing the wide variety of impaired fracture healing phenotypes in Neurofibromatosis Type 1 with eight key factors: a computational study. Sci Rep 2016; 7:20010. [PMID: 26822862 PMCID: PMC4731811 DOI: 10.1038/srep20010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 11/27/2015] [Indexed: 02/07/2023] Open
Abstract
Congenital pseudarthrosis of the tibia (CPT) is a rare disease which normally presents itself during early childhood by anterolateral bowing of the tibia and spontaneous tibial fractures. Although the exact etiology of CPT is highly debated, 40–80% of CPT patients are carriers of a mutation in the Neurofibromatosis Type 1 (NF1) gene, which can potentially result in an altered phenotype of the skeletal cells and impaired bone healing. In this study we use a computational model of bone regeneration to examine the effect of the Nf1 mutation on bone fracture healing by altering the parameter values of eight key factors which describe the aberrant cellular behaviour of Nf1 haploinsufficient and Nf1 bi-allelically inactivated cells. We show that the computational model is able to predict the formation of a hamartoma as well as a wide variety of CPT phenotypes through different combinations of altered parameter values. A sensitivity analysis by “Design of Experiments” identified the impaired endochondral ossification process and increased infiltration of fibroblastic cells as key contributors to the degree of severity of CPT. Hence, the computational model results have added credibility to the experimental hypothesis of a genetic cause (i.e. Nf1 mutation) for CPT.
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17
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Hojjat-Farsangi M. Targeting non-receptor tyrosine kinases using small molecule inhibitors: an overview of recent advances. J Drug Target 2015. [DOI: 10.3109/1061186x.2015.1068319] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Mohammad Hojjat-Farsangi
- Department of Oncology-Pathology, Immune and Gene Therapy Lab, Cancer Center Karolinska (CCK), Karolinska University Hospital Solna and Karolinska Institute, Stockholm, Sweden and
- Department of Immunology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
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Zhang W, Xue D, Hu D, Xie T, Tao Y, Zhu T, Chen E, Pan Z. Secreted klotho protein attenuates osteogenic differentiation of human bone marrow mesenchymal stem cells in vitro via inactivation of the FGFR1/ERK signaling pathway. Growth Factors 2015; 33:356-65. [PMID: 26607681 DOI: 10.3109/08977194.2015.1108313] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Increasing evidence indicates that the osteogenic differentiation of mesenchymal stem cells (MSCs) is related to bone formation, heterotopic ossification, and even vascular calcification. Therefore, it is essential to understand the microenvironment that regulates these processes. The Klotho gene plays an important role in tissue mineralization, and its secreted protein functions as a hormone. We investigated the effects of secreted Klotho protein on the osteogenesis of human bone marrow MSC (hBMSCs). To this end, the cells received osteogenic medium with or without Klotho protein. The results showed that osteoblast-specific gene expression and mineral deposition were decreased when MSCs were incubated with Klotho. Klotho reduced the expression of fibroblast growth factor receptor 1 (FGFR1) and phosphorylated extracellular signal-regulated kinase 1/2. However, both MEK and FGFR1 inhibitors delayed bone mineral formation more than Klotho. These data suggest that secreted Klotho protein attenuates the osteogenic differentiation of hBMSCs in vitro through FGFR1/ERK signaling.
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Affiliation(s)
- Wei Zhang
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Deting Xue
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Dongcai Hu
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Tao Xie
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Yiqing Tao
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Ting Zhu
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Erman Chen
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
| | - Zhijun Pan
- a Department of Orthopedics , Second Affiliated Hospital, School of Medicine, Zhejiang University , Hangzhou , People's Republic of China
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Seime T, Kolind M, Mikulec K, Summers MA, Cantrill L, Little DG, Schindeler A. Inducible cell labeling and lineage tracking during fracture repair. Dev Growth Differ 2014; 57:10-23. [PMID: 25389084 DOI: 10.1111/dgd.12184] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 09/24/2014] [Accepted: 09/28/2014] [Indexed: 12/26/2022]
Abstract
Mouse models incorporating inducible Cre-ERT2/LoxP recombination coupled with sensitive fluorescent reporter lines are being increasingly used to track cell lineages in vivo. In this study we use two inducible reporter strains, Ai9iCol2a1 (Ai9×Col2a1-creERT2) to track contribution of chondrogenic progenitors during bone regeneration in a closed fracture model and Ai9i UBC (Ai9×UBC-creERT2) to examine methods for inducing localized recombination. By comparing with Ai9 littermate controls as well as inducible reporter mice not dosed with tamoxifen, we revealed significant leakiness of the CreERT2 system, particularly in the bone marrow of both lines. These studies highlight the challenges associated with highly sensitive reporters that may be activated without induction in tissues where the CreERT2 fusion is expressed. Examination of the growth plate in the Ai9iCol2a1 strain showed cells of the osteochondral lineage (cell co-staining with chondrocyte and osteoblast markers) labeled with the tdTom reporter. However, no such labeling was noted in healing fractures of Ai9iCol2a1 mice. Attempts to label a single limb using intramuscular injection of 4-hydroxytamoxifen in the Ai9i UBC strain resulted in complete labeling of the entire animal, comparable to intraperitoneal injection. While a challenge to interpret, these data are nonetheless informative regarding the limitations of these inducible reporter models, and justify caution and expansive controls in future studies using such models.
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Affiliation(s)
- Till Seime
- Department of Orthopaedic Research & Biotechnology, The Children's Hospital at Westmead, Locked Bag 4001, Westmead, Sydney, NSW, 2145, Australia; MCI Management Center Innsbruck, A-6020 Innsbruck, Austria
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