101
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Tsutsumi R, Tran MP, Cooper KL. Changing While Staying the Same: Preservation of Structural Continuity During Limb Evolution by Developmental Integration. Integr Comp Biol 2018; 57:1269-1280. [PMID: 28992070 DOI: 10.1093/icb/icx092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
More than 150 years since Charles Darwin published "On the Origin of Species", gradual evolution by natural selection is still not fully reconciled with the apparent sudden appearance of complex structures, such as the bat wing, with highly derived functions. This is in part because developmental genetics has not yet identified the number and types of mutations that accumulated to drive complex morphological evolution. Here, we consider the experimental manipulations in laboratory model systems that suggest tissue interdependence and mechanical responsiveness during limb development conceptually reduce the genetic complexity required to reshape the structure as a whole. It is an exciting time in the field of evolutionary developmental biology as emerging technical approaches in a variety of non-traditional laboratory species are on the verge of filling the gaps between theory and evidence to resolve this sesquicentennial debate.
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Affiliation(s)
- Rio Tsutsumi
- Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093-0380, USA
| | - Mai P Tran
- Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093-0380, USA
| | - Kimberly L Cooper
- Division of Biological Sciences, University of California San Diego, La Jolla, CA 92093-0380, USA
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102
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Schneider RA. Neural crest and the origin of species-specific pattern. Genesis 2018; 56:e23219. [PMID: 30134069 PMCID: PMC6108449 DOI: 10.1002/dvg.23219] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 12/20/2022]
Abstract
For well over half of the 150 years since the discovery of the neural crest, the special ability of these cells to function as a source of species-specific pattern has been clearly recognized. Initially, this observation arose in association with chimeric transplant experiments among differentially pigmented amphibians, where the neural crest origin for melanocytes had been duly noted. Shortly thereafter, the role of cranial neural crest cells in transmitting species-specific information on size and shape to the pharyngeal arch skeleton as well as in regulating the timing of its differentiation became readily apparent. Since then, what has emerged is a deeper understanding of how the neural crest accomplishes such a presumably difficult mission, and this includes a more complete picture of the molecular and cellular programs whereby neural crest shapes the face of each species. This review covers studies on a broad range of vertebrates and describes neural-crest-mediated mechanisms that endow the craniofacial complex with species-specific pattern. A major focus is on experiments in quail and duck embryos that reveal a hierarchy of cell-autonomous and non-autonomous signaling interactions through which neural crest generates species-specific pattern in the craniofacial integument, skeleton, and musculature. By controlling size and shape throughout the development of these systems, the neural crest underlies the structural and functional integration of the craniofacial complex during evolution.
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Affiliation(s)
- Richard A. Schneider
- Department of Orthopedic SurgeryUniversity of California at San Francisco, 513 Parnassus AvenueS‐1161San Francisco, California
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103
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Font Tellado S, Chiera S, Bonani W, Poh PS, Migliaresi C, Motta A, Balmayor ER, van Griensven M. Heparin functionalization increases retention of TGF-β2 and GDF5 on biphasic silk fibroin scaffolds for tendon/ligament-to-bone tissue engineering. Acta Biomater 2018; 72:150-166. [PMID: 29550439 DOI: 10.1016/j.actbio.2018.03.017] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 02/28/2018] [Accepted: 03/07/2018] [Indexed: 02/08/2023]
Abstract
The tendon/ligament-to-bone transition (enthesis) is a highly specialized interphase tissue with structural gradients of extracellular matrix composition, collagen molecule alignment and mineralization. These structural features are essential for enthesis function, but are often not regenerated after injury. Tissue engineering is a promising strategy for enthesis repair. Engineering of complex tissue interphases such as the enthesis is likely to require a combination of biophysical, biological and chemical cues to achieve functional tissue regeneration. In this study, we cultured human primary adipose-derived mesenchymal stem cells (AdMCs) on biphasic silk fibroin scaffolds with integrated anisotropic (tendon/ligament-like) and isotropic (bone/cartilage like) pore alignment. We functionalized those scaffolds with heparin and explored their ability to deliver transforming growth factor β2 (TGF-β2) and growth/differentiation factor 5 (GDF5). Heparin functionalization increased the amount of TGF-β2 and GDF5 remaining attached to the scaffold matrix and resulted in biological effects at low growth factor doses. We analyzed the combined impact of pore alignment and growth factors on AdMSCs. TGF-β2 and pore anisotropy synergistically increased the expression of tendon/ligament markers and collagen I protein content. In addition, the combined delivery of TGF-β2 and GDF5 enhanced the expression of cartilage markers and collagen II protein content on substrates with isotropic porosity, whereas enthesis markers were enhanced in areas of mixed anisotropic/isotropic porosity. Altogether, the data obtained in this study improves current understanding on the combined effects of biological and structural cues on stem cell fate and presents a promising strategy for tendon/ligament-to-bone regeneration. STATEMENT OF SIGNIFICANCE Regeneration of the tendon/ligament-to-bone interphase (enthesis) is of significance in the repair of ruptured tendons/ligaments to bone to improve implant integration and clinical outcome. This study proposes a novel approach for enthesis regeneration based on a biomimetic and integrated tendon/ligament-to-bone construct, stem cells and heparin-based delivery of growth factors. We show that heparin can keep growth factors local and biologically active at low doses, which is critical to avoid supraphysiological doses and associated side effects. In addition, we identify synergistic effects of biological (growth factors) and structural (pore alignment) cues on stem cells. These results improve current understanding on the combined impact of biological and structural cues on the multi-lineage differentiation capacity of stem cells for regenerating complex tissue interphases.
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104
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Jensen PT, Lambertsen KL, Frich LH. Assembly, maturation, and degradation of the supraspinatus enthesis. J Shoulder Elbow Surg 2018; 27:739-750. [PMID: 29329904 DOI: 10.1016/j.jse.2017.10.030] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 10/22/2017] [Accepted: 10/27/2017] [Indexed: 02/01/2023]
Abstract
The development of the rotator cuff enthesis is still poorly understood. The processes in the early and late developmental steps are gradually elucidated, but it is still unclear how cell activities are coordinated during development and maturation of the structured enthesis. This review summarizes current knowledge about development and age-related degradation of the supraspinatus enthesis. Healing and repair of an injured and degenerated supraspinatus enthesis also remain a challenge, as the original graded transitional tissue of the fibrocartilaginous insertion is not re-created after the tendon is surgically reattached to bone. Instead, mechanically inferior and disorganized tissue forms at the healing site because of scar tissue formation. Consequently, the enthesis never reaches mechanical properties comparable to those of the native enthesis. So far, no novel biologic healing approach has been successful in enhancing healing of the injured enthesis. The results revealed in this review imply the need for further research to pave the way for better treatment of patients with rotator cuff disorder.
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Affiliation(s)
- Peter T Jensen
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Kate L Lambertsen
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Lars H Frich
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Department of Orthopaedics and Traumatology, Odense University Hospital, Odense, Denmark.
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105
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Gorissen BMC, Wolschrijn CF, van Rietbergen B, Rieppo L, Saarakkala S, van Weeren PR. Trabecular and subchondral bone development of the talus and distal tibia from foal to adult in the warmblood horse. Anat Histol Embryol 2018; 47:206-215. [DOI: 10.1111/ahe.12341] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 01/11/2018] [Indexed: 01/13/2023]
Affiliation(s)
- B. M. C. Gorissen
- Department of Pathobiology, Anatomy and Physiology Division; Faculty of Veterinary Medicine; Utrecht University; Utrecht The Netherlands
| | - C. F. Wolschrijn
- Department of Pathobiology, Anatomy and Physiology Division; Faculty of Veterinary Medicine; Utrecht University; Utrecht The Netherlands
| | - B. van Rietbergen
- Department of Biomedical Engineering; Orthopaedic Biomechanics Division; Eindhoven University of Technology; Eindhoven The Netherlands
| | - L. Rieppo
- Research Unit of Medical Imaging; Physics and Technology; Faculty of Medicine; University of Oulu; Oulu Finland
| | - S. Saarakkala
- Research Unit of Medical Imaging; Physics and Technology; Faculty of Medicine; University of Oulu; Oulu Finland
- Medical Research Center; University of Oulu; Oulu University Hospital; Oulu Finland
- Department of Diagnostic Radiology; Oulu University Hospital; Oulu Finland
| | - P. R. van Weeren
- Department of Equine Sciences; Faculty of Veterinary Medicine; Utrecht University; Utrecht The Netherlands
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106
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Lee-Barthel A, Lee CA, Vidal MA, Baar K. Localized BMP-4 release improves the enthesis of engineered bone-to-bone ligaments. TRANSLATIONAL SPORTS MEDICINE 2018. [DOI: 10.1002/tsm2.9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- A. Lee-Barthel
- Department of Biomedical Engineering; University of California Davis; Davis CA USA
| | - C. A. Lee
- Department of Orthopaedic Surgery; University of California Davis; Sacramento CA USA
| | - M. A. Vidal
- Department of Surgical and Radiological Sciences; University of California Davis; Davis CA USA
| | - K. Baar
- Department of Neurobiology, Physiology, and Behavior; University of California Davis; Davis CA USA
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107
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Cong XX, Rao XS, Lin JX, Liu XC, Zhang GA, Gao XK, He MY, Shen WL, Fan W, Pioletti D, Zheng LL, Liu HH, Yin Z, Low BC, Schweitzer R, Ouyang H, Chen X, Zhou YT. Activation of AKT-mTOR Signaling Directs Tenogenesis of Mesenchymal Stem Cells. Stem Cells 2018; 36:527-539. [PMID: 29315990 DOI: 10.1002/stem.2765] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 12/04/2017] [Accepted: 12/04/2017] [Indexed: 01/28/2023]
Abstract
Tendon repair is a clinical challenge because of the limited understanding on tenogenesis. The synthesis of type I collagen (Collagen I) and other extracellular matrix are essential for tendon differentiation and homeostasis. Current studies on tenogenesis focused mostly on the tenogenic transcriptional factors while the signaling controlling tenogenesis on translational level remains largely unknown. Here, we showed that mechanistic target of rapamycin (mTOR) signaling was activated by protenogenic growth factor, transforming growth factors beta1, and insulin-like growth factor-I. The expression of mTOR was upregulated during tenogenesis of mesenchymal stem cells (MSCs). Moreover, mTOR was downregulated in human tendinopathy tissues and was inactivated upon statin treatment. Both inhibition and depletion of AKT or mTOR significantly reduced type I collagen production and impaired tenogenesis of MSCs. Tendon specific-ablation of mTOR resulted in tendon defect and reduction of Collagen I. However, there is no evident downregulation of tendon associated collagens at the transcription level. Our study demonstrated that AKT-mTOR axis is a key mediator of tendon differentiation and provided a novel therapeutic target for tendinopathy and tendon injuries. Stem Cells 2018;36:527-539.
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Affiliation(s)
- Xiao Xia Cong
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Xi Sheng Rao
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Jun Xin Lin
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Xiao Ceng Liu
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Guang An Zhang
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Xiu Kui Gao
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Min Yi He
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Wei Liang Shen
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China.,Department of Orthopaedic Surgery, the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Wei Fan
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Dominique Pioletti
- Laboratory of Biomechanical Orthopedics, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland
| | - Li Ling Zheng
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Huan Huan Liu
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Zi Yin
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China
| | - Boon Chuan Low
- Mechanobiology Institute, Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Ronen Schweitzer
- Portland Shriners Hospital, Oregon Health and Science University, Portland, Oregon, USA
| | - Hongwei Ouyang
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China.,China Orthopedic Regenerative Medicine Group (CORMed), Hangzhou, People's Republic of China
| | - Xiao Chen
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China.,China Orthopedic Regenerative Medicine Group (CORMed), Hangzhou, People's Republic of China
| | - Yi Ting Zhou
- Department of Biochemistry and Molecular Biology, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.,Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine, Hangzhou, People's Republic of China.,China Orthopedic Regenerative Medicine Group (CORMed), Hangzhou, People's Republic of China
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108
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Hirasawa T, Kuratani S. Evolution of the muscular system in tetrapod limbs. ZOOLOGICAL LETTERS 2018; 4:27. [PMID: 30258652 PMCID: PMC6148784 DOI: 10.1186/s40851-018-0110-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 09/04/2018] [Indexed: 05/16/2023]
Abstract
While skeletal evolution has been extensively studied, the evolution of limb muscles and brachial plexus has received less attention. In this review, we focus on the tempo and mode of evolution of forelimb muscles in the vertebrate history, and on the developmental mechanisms that have affected the evolution of their morphology. Tetrapod limb muscles develop from diffuse migrating cells derived from dermomyotomes, and the limb-innervating nerves lose their segmental patterns to form the brachial plexus distally. Despite such seemingly disorganized developmental processes, limb muscle homology has been highly conserved in tetrapod evolution, with the apparent exception of the mammalian diaphragm. The limb mesenchyme of lateral plate mesoderm likely plays a pivotal role in the subdivision of the myogenic cell population into individual muscles through the formation of interstitial muscle connective tissues. Interactions with tendons and motoneuron axons are involved in the early and late phases of limb muscle morphogenesis, respectively. The mechanism underlying the recurrent generation of limb muscle homology likely resides in these developmental processes, which should be studied from an evolutionary perspective in the future.
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Affiliation(s)
- Tatsuya Hirasawa
- Laboratory for Evolutionary Morphology, RIKEN Center for Biosystems Dynamics Research (BDR), 2-2-3 Minatojima-minami, Chuo-ku, Kobe, Hyogo 650-0047 Japan
| | - Shigeru Kuratani
- Laboratory for Evolutionary Morphology, RIKEN Center for Biosystems Dynamics Research (BDR), 2-2-3 Minatojima-minami, Chuo-ku, Kobe, Hyogo 650-0047 Japan
- Evolutionary Morphology Laboratory, RIKEN Cluster for Pioneering Research (CPR), 2-2-3 Minatojima-minami, Chuo-ku, Kobe, Hyogo 650-0047 Japan
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109
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Wang H, Yi J, Li X, Xiao Y, Dhakal K, Zhou J. ALS-associated mutation SOD1 G93A leads to abnormal mitochondrial dynamics in osteocytes. Bone 2018; 106:126-138. [PMID: 29030231 PMCID: PMC5718158 DOI: 10.1016/j.bone.2017.10.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 10/05/2017] [Accepted: 10/09/2017] [Indexed: 12/13/2022]
Abstract
While the death of motor neuron is a pathological hallmark of amyotrophic lateral sclerosis (ALS), defects in other cell types or organs may also actively contribute to ALS disease progression. ALS patients experience progressive skeletal muscle wasting that may not only exacerbate neuronal degeneration, but likely has a significant impact on bone function. In our previous published study, we have discovered severe bone loss in an ALS mouse model with overexpression of ALS-associated mutation SOD1G93A (G93A). Here we further provide a mechanistic understanding of the bone loss in ALS animal and cellular models. Combining mitochondrial fluorescent indicators and confocal live cell imaging, we discovered abnormalities in mitochondrial network and dynamics in primary osteocytes derived from the same ALS mouse model G93A. Those mitochondrial defects occur in ALS mice after the onset of neuromuscular symptoms, indicating that mitochondria in bone cells respond to muscle atrophy during ALS disease progression. To examine whether ALS mutation has a direct contribution to mitochondrial dysfunction independent of muscle atrophy, we evaluated mitochondrial morphology and motility in cultured osteocytes (MLO-Y4) with overexpression of mitochondrial targeted SOD1G93A. Compared with osteocytes overexpressing the wild type SOD1 as a control, the SOD1G93A osteocytes showed similar defects in mitochondrial network and dynamic as that of the primary osteocytes derived from the ALS mouse model. In addition, we further discovered that overexpression of SOD1G93A enhanced the expression level of dynamin-related protein 1 (Drp1), a key protein promoting mitochondrial fission activity, and reduced the expression level of optic atrophy protein 1 (OPA1), a key protein related to mitochondrial fusion. A specific mitochondrial fission inhibitor (Mdivi-1) partially reversed the effect of SOD1G93A on mitochondrial network and dynamics, indicating that SOD1G93A likely promotes mitochondrial fission, but suppresses the fusion activity. Our data provide the first evidence that mitochondria show abnormality in osteocytes derived from an ALS mouse model. The accumulation of mutant SOD1G93A protein inside mitochondria directly causes dysfunction in mitochondrial dynamics in cultured MLO-Y4 osteocytes. In addition, the ALS mutation SOD1G93A-mediated dysfunction in mitochondrial dynamics is associated with an enhanced apoptosis in osteocytes, which could be a potential mechanism underlying the bone loss during ALS progression.
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Affiliation(s)
- Huan Wang
- Kansas City University of Medicine and Bioscience, Kansas City, MO, USA
| | - Jianxun Yi
- Kansas City University of Medicine and Bioscience, Kansas City, MO, USA
| | - Xuejun Li
- Kansas City University of Medicine and Bioscience, Kansas City, MO, USA
| | - Yajuan Xiao
- Kansas City University of Medicine and Bioscience, Kansas City, MO, USA
| | - Kamal Dhakal
- Kansas City University of Medicine and Bioscience, Kansas City, MO, USA
| | - Jingsong Zhou
- Kansas City University of Medicine and Bioscience, Kansas City, MO, USA.
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110
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Lim J, Munivez E, Jiang MM, Song IW, Gannon F, Keene DR, Schweitzer R, Lee BH, Joeng KS. mTORC1 Signaling is a Critical Regulator of Postnatal Tendon Development. Sci Rep 2017; 7:17175. [PMID: 29215029 PMCID: PMC5719403 DOI: 10.1038/s41598-017-17384-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 11/24/2017] [Indexed: 12/11/2022] Open
Abstract
Tendons transmit contractile forces between musculoskeletal tissues. Whereas the biomechanical properties of tendons have been studied extensively, the molecular mechanisms regulating postnatal tendon development are not well understood. Here we examine the role of mTORC1 signaling in postnatal tendon development using mouse genetic approaches. Loss of mTORC1 signaling by removal of Raptor in tendons caused severe tendon defects postnatally, including decreased tendon thickness, indicating that mTORC1 is necessary for postnatal tendon development. By contrast, activation of mTORC1 signaling in tendons increased tendon cell numbers and proliferation. In addition, Tsc1 conditional knockout mice presented severely disorganized collagen fibers and neovascularization in the tendon midsubstance. Interestingly, collagen fibril diameter was significantly reduced in both Raptor and Tsc1 conditional knockout mice, albeit with variations in severity. We performed RNA-seq analysis using Achilles tendons to investigate the molecular changes underlying these tendon phenotypes. Raptor conditional knockout mice showed decreased extracellular matrix (ECM) structure-related gene expression, whereas Tsc1 conditional knockout mice exhibited changes in genes regulating TGF-β/BMP/FGF signaling, as well as in genes controlling ECM structure and disassembly. Collectively, our studies suggest that maintaining physiological levels of mTORC1 signaling is essential for postnatal tendon development and maturation.
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Affiliation(s)
- Joohyun Lim
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Elda Munivez
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Ming-Ming Jiang
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - I-Wen Song
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Francis Gannon
- Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Douglas R Keene
- Research Center, Shriners Hospital for Children, Portland, OR, 97239, USA
| | - Ronen Schweitzer
- Research Center, Shriners Hospital for Children, Portland, OR, 97239, USA
| | - Brendan H Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA.
| | - Kyu Sang Joeng
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
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111
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Abstract
During embryogenesis, the musculoskeletal system develops while containing within itself a force generator in the form of the musculature. This generator becomes functional relatively early in development, exerting an increasing mechanical load on neighboring tissues as development proceeds. A growing body of evidence indicates that such mechanical forces can be translated into signals that combine with the genetic program of organogenesis. This unique situation presents both a major challenge and an opportunity to the other tissues of the musculoskeletal system, namely bones, joints, tendons, ligaments and the tissues connecting them. Here, we summarize the involvement of muscle-induced mechanical forces in the development of various vertebrate musculoskeletal components and their integration into one functional unit.
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Affiliation(s)
- Neta Felsenthal
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Elazar Zelzer
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
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112
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Ahn JO, Chung JY, Kim DH, Im W, Kim SH. Differences of RNA Expression in the Tendon According to Anatomic Outcomes in Rotator Cuff Repair. Am J Sports Med 2017; 45:2995-3003. [PMID: 28661723 DOI: 10.1177/0363546517713198] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Despite increased understanding of the pathophysiology of rotator cuff tears and the evolution of rotator cuff repair, healing failure remains a substantial problem. The critical roles played by biological factors have been emphasized, but little is known of the implications of gene expression profile differences at the time of repair. PURPOSE To document the relationship between the perioperative gene expression of healed and unhealed rotator cuffs by RNA microarray analysis. STUDY DESIGN Case-control study; Level of evidence, 3. METHODS Superior (supraspinatus involvement) and posterosuperior (supraspinatus and infraspinatus involvement) tears were included in the study. Samples of rotator cuff tendons were prospectively collected during rotator cuff surgery. Three samples were harvested at the tendon ends of tears from the anterior, middle (apex), and posterior parts using an arthroscopic punch. Seven patients with an unhealed rotator cuff were matched one-to-one with patients with a healed rotator cuff by sex, age, tear size, and fatty degeneration of rotator cuff muscles. mRNA microarray analysis was used to identify genetic differences between healed and unhealed rotator cuff tendons. Gene ontology and gene association files were obtained from the Gene Ontology Consortium, and the Gene Ontology system in DAVID was used to identify enhanced biological processes. RESULTS Microarray analyses identified 262 genes that were differentially expressed by at least 1.5-fold between the healed and unhealed groups. Overall, in the healed group, 103 genes were significantly downregulated, and 159 were significantly upregulated. DAVID Functional Annotation Cluster analysis showed that in the healed group, the genes most upregulated were related to the G protein-coupled receptor protein signaling pathway and to the neurological system. On the other hand, the genes most downregulated were related to immune and inflammatory responses. BMP5 was the gene most upregulated in the healed group, and the majority of downregulated genes were involved in the immune/inflammatory response. CONCLUSION The downregulation of inflammatory response genes and the upregulation of cell differentiation genes in torn rotator cuffs at the time of surgery are related to rotator cuff healing. These results provide useful baseline information for future biological studies on rotator cuff healing.
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Affiliation(s)
- Jin-Ok Ahn
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul, Republic of Korea
| | - Jin-Young Chung
- Department of Veterinary Internal Medicine and Institute of Veterinary Science, College of Veterinary Medicine, Kangwon National University, Chuncheon, Republic of Korea
| | - Do Hoon Kim
- Department of Orthopedic Surgery, College of Medicine, Seoul National University Hospital, Seoul National University, Seoul, Republic of Korea
| | - Wooseok Im
- Department of Neurology, Biomedical Research Institute, Seoul National University Hospital, Seoul National University, Seoul, Republic of Korea
| | - Sae Hoon Kim
- Department of Orthopedic Surgery, College of Medicine, Seoul National University Hospital, Seoul National University, Seoul, Republic of Korea
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113
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Asahara H, Inui M, Lotz MK. Tendons and Ligaments: Connecting Developmental Biology to Musculoskeletal Disease Pathogenesis. J Bone Miner Res 2017; 32:1773-1782. [PMID: 28621492 PMCID: PMC5585011 DOI: 10.1002/jbmr.3199] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 06/08/2017] [Accepted: 06/14/2017] [Indexed: 01/09/2023]
Abstract
Tendons and ligaments provide connections between muscle and bone or bone and bone to enable locomotion. Damage to tendons and ligaments caused by acute or chronic injury or associated with aging and arthritis is a prevalent cause of disability. Improvements in approaches for the treatment of these conditions depend on a better understanding of tendon and ligament development, cell biology, and pathophysiology. This review focuses on recent advances in the discovery of transcription factors that control ligament and tendon cell differentiation, how cell and extracellular matrix homeostasis are altered in disease, and how this new insight can lead to novel therapeutic approaches. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Hiroshi Asahara
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
- Department of Systems BioMedicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Masafumi Inui
- Laboratory of Animal Regeneration Systemology, Department of Life Science, School of Agriculture, Meiji University, Kanagawa, 214-8571
| | - Martin K. Lotz
- Department of Molecular Medicine, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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114
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Arvind V, Huang AH. Mechanobiology of limb musculoskeletal development. Ann N Y Acad Sci 2017; 1409:18-32. [PMID: 28833194 DOI: 10.1111/nyas.13427] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 05/30/2017] [Accepted: 06/07/2017] [Indexed: 12/26/2022]
Abstract
While there has been considerable progress in identifying molecular regulators of musculoskeletal development, the role of physical forces in regulating induction, differentiation, and patterning events is less well understood. Here, we highlight recent findings in this area, focusing primarily on model systems that test the mechanical regulation of skeletal and tendon development in the limb. We also discuss a few of the key signaling pathways and mechanisms that have been implicated in mechanotransduction and highlight current gaps in knowledge and opportunities for further research in the field.
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Affiliation(s)
- Varun Arvind
- Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Alice H Huang
- Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, New York, New York
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115
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Blecher R, Krief S, Galili T, Assaraf E, Stern T, Anekstein Y, Agar G, Zelzer E. The Proprioceptive System Regulates Morphologic Restoration of Fractured Bones. Cell Rep 2017; 20:1775-1783. [PMID: 28834742 PMCID: PMC5575358 DOI: 10.1016/j.celrep.2017.07.073] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Revised: 07/12/2017] [Accepted: 07/20/2017] [Indexed: 12/29/2022] Open
Abstract
Successful fracture repair requires restoration of bone morphology and mechanical integrity. Recent evidence shows that fractured bones of neonatal mice undergo spontaneous realignment, dubbed "natural reduction." Here, we show that natural reduction is regulated by the proprioceptive system and improves with age. Comparison among mice of different ages revealed, surprisingly, that 3-month-old mice exhibited more rapid and effective natural reduction than newborns. Fractured bones of null mutants for transcription factor Runx3, lacking functional proprioceptors, failed to realign properly. Blocking Runx3 expression in the peripheral nervous system, but not in limb mesenchyme, recapitulated the null phenotype, as did inactivation of muscles flanking the fracture site. Egr3 knockout mice, which lack muscle spindles but not Golgi tendon organs, displayed a less severe phenotype, suggesting that both receptor types, as well as muscle contraction, are required for this regulatory mechanism. These findings uncover a physiological role for proprioception in non-autonomous regulation of skeletal integrity.
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Affiliation(s)
- Ronen Blecher
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; Department of Orthopedic Surgery, Assaf Harofeh Medical Center, Zerrifin 70300, Israel, affiliated with the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Sharon Krief
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Tal Galili
- Department of Statistics and Operations Research, Tel Aviv University, Tel Aviv 69978, Israel
| | - Eran Assaraf
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel; Department of Orthopedic Surgery, Assaf Harofeh Medical Center, Zerrifin 70300, Israel, affiliated with the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Tomer Stern
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yoram Anekstein
- Department of Orthopedic Surgery, Assaf Harofeh Medical Center, Zerrifin 70300, Israel, affiliated with the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Gabriel Agar
- Department of Orthopedic Surgery, Assaf Harofeh Medical Center, Zerrifin 70300, Israel, affiliated with the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Elazar Zelzer
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
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116
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Butterfield NC, Qian C, Logan MPO. Pitx1 determines characteristic hindlimb morphologies in cartilage micromass culture. PLoS One 2017; 12:e0180453. [PMID: 28746404 PMCID: PMC5528256 DOI: 10.1371/journal.pone.0180453] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 05/18/2017] [Indexed: 01/13/2023] Open
Abstract
The shapes of homologous skeletal elements in the vertebrate forelimb and hindlimb are distinct, with each element exquisitely adapted to their divergent functions. Many of the signals and signalling pathways responsible for patterning the developing limb bud are common to both forelimb and hindlimb. How disparate morphologies are generated from common signalling inputs during limb development remains poorly understood. We show that, similar to what has been shown in the chick, characteristic differences in mouse forelimb and hindlimb cartilage morphology are maintained when chondrogenesis proceeds in vitro away from the endogenous limb bud environment. Chondrogenic nodules that form in high-density micromass cultures derived from forelimb and hindlimb buds are consistently different in size and shape. We described analytical tools we have developed to quantify these differences in nodule morphology and demonstrate that characteristic hindlimb nodule morphology is lost in the absence of the hindlimb-restricted limb modifier gene Pitx1. Furthermore, we show that ectopic expression of Pitx1 in the forelimb is sufficient to generate nodule patterns characteristic of the hindlimb. We also demonstrate that hindlimb cells are less adhesive to the tissue culture substrate and, within the limb environment, to the extracellular matrix and to each other. These results reveal autonomously programmed differences in forelimb and hindlimb cartilage precursors of the limb skeleton are controlled, at least in part, by Pitx1 and suggest this has an important role in generating distinct limb-type morphologies. Our results demonstrate that the micromass culture system is ideally suited to study cues governing morphogenesis of limb skeletal elements in a simple and experimentally tractable in vitro system that reflects in vivo potential.
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Affiliation(s)
- Natalie C. Butterfield
- Division of Developmental Biology, Medical Research Council – National Institute for Medical Research, London, United Kingdom
| | - Chen Qian
- Confocal Image Analysis Lab, Medical Research Council – National Institute for Medical Research, London, United Kingdom
| | - Malcolm P. O. Logan
- Division of Developmental Biology, Medical Research Council – National Institute for Medical Research, London, United Kingdom
- * E-mail:
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117
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Deymier AC, An Y, Boyle JJ, Schwartz AG, Birman V, Genin GM, Thomopoulos S, Barber AH. Micro-mechanical properties of the tendon-to-bone attachment. Acta Biomater 2017; 56:25-35. [PMID: 28088669 DOI: 10.1016/j.actbio.2017.01.037] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 12/14/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
The tendon-to-bone attachment (enthesis) is a complex hierarchical tissue that connects stiff bone to compliant tendon. The attachment site at the micrometer scale exhibits gradients in mineral content and collagen orientation, which likely act to minimize stress concentrations. The physiological micromechanics of the attachment thus define resultant performance, but difficulties in sample preparation and mechanical testing at this scale have restricted understanding of structure-mechanical function. Here, microscale beams from entheses of wild type mice and mice with mineral defects were prepared using cryo-focused ion beam milling and pulled to failure using a modified atomic force microscopy system. Micromechanical behavior of tendon-to-bone structures, including elastic modulus, strength, resilience, and toughness, were obtained. Results demonstrated considerably higher mechanical performance at the micrometer length scale compared to the millimeter tissue length scale, describing enthesis material properties without the influence of higher order structural effects such as defects. Micromechanical investigation revealed a decrease in strength in entheses with mineral defects. To further examine structure-mechanical function relationships, local deformation behavior along the tendon-to-bone attachment was determined using local image correlation. A high compliance zone near the mineralized gradient of the attachment was clearly identified and highlighted the lack of correlation between mineral distribution and strain on the low-mineral end of the attachment. This compliant region is proposed to act as an energy absorbing component, limiting catastrophic failure within the tendon-to-bone attachment through higher local deformation. This understanding of tendon-to-bone micromechanics demonstrates the critical role of micrometer scale features in the mechanics of the tissue. STATEMENT OF SIGNIFICANCE The tendon-to-bone attachment (enthesis) is a complex hierarchical tissue with features at a numerous scales that dissipate stress concentrations between compliant tendon and stiff bone. At the micrometer scale, the enthesis exhibits gradients in collagen and mineral composition and organization. However, the physiological mechanics of the enthesis at this scale remained unknown due to difficulty in preparing and testing micrometer scale samples. This study is the first to measure the tensile mechanical properties of the enthesis at the micrometer scale. Results demonstrated considerably enhanced mechanical performance at the micrometer length scale compared to the millimeter tissue length scale and identified a high-compliance zone near the mineralized gradient of the attachment. This understanding of tendon-to-bone micromechanics demonstrates the critical role of micrometer scale features in the mechanics of the tissue.
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118
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Matthews DG, Albertson RC. Effect of craniofacial genotype on the relationship between morphology and feeding performance in cichlid fishes. Evolution 2017; 71:2050-2061. [PMID: 28598501 DOI: 10.1111/evo.13289] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 05/12/2017] [Accepted: 05/22/2017] [Indexed: 01/11/2023]
Abstract
The relationship between morphology and performance is complex, but important for understanding the adaptive nature of morphological variation. Recent studies have sought to better understand this system by illuminating the interconnectedness of different functional systems; however, the role of genetics is often overlooked. In this study, we attempt to gain insights into this relationship by examining the effect of genotypic variation at putative craniofacial loci on the relationship between morphology and feeding performance in cichlids. We studied two morphologically disparate species, as well as a morphologically intermediate hybrid population. We assessed feeding performance, jaw protrusion, and general facial morphology for each fish. We also genotyped hybrid animals at six previously identified craniofacial loci. Cichlid species were found to differ in facial geometry, kinematic morphology, and performance. Significant correlations were also noted between these variables; however, the explanatory power of facial geometry in predicting performance was relatively poor. Notably, when hybrids were grouped by genotype, the relationship between shape and performance improved. This relationship was especially robust in animals with the specialist allele at sox9b, a well-characterized regulator of craniofacial development. These data suggest a novel role for genotype in influencing complex relationships between form and function.
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Affiliation(s)
- David G Matthews
- Department of Biology, University of Massachusetts Amherst, Amherst, Massachusetts, 01003
| | - R Craig Albertson
- Department of Biology, University of Massachusetts Amherst, Amherst, Massachusetts, 01003
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119
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Font Tellado S, Bonani W, Balmayor ER, Foehr P, Motta A, Migliaresi C, van Griensven M. * Fabrication and Characterization of Biphasic Silk Fibroin Scaffolds for Tendon/Ligament-to-Bone Tissue Engineering. Tissue Eng Part A 2017; 23:859-872. [PMID: 28330431 DOI: 10.1089/ten.tea.2016.0460] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Tissue engineering is an attractive strategy for tendon/ligament-to-bone interface repair. The structure and extracellular matrix composition of the interface are complex and allow for a gradual mechanical stress transfer between tendons/ligaments and bone. Thus, scaffolds mimicking the structural features of the native interface may be able to better support functional tissue regeneration. In this study, we fabricated biphasic silk fibroin scaffolds designed to mimic the gradient in collagen molecule alignment present at the interface. The scaffolds had two different pore alignments: anisotropic at the tendon/ligament side and isotropic at the bone side. Total porosity ranged from 50% to 80% and the majority of pores (80-90%) were <100-300 μm. Young's modulus varied from 689 to 1322 kPa depending on the type of construct. In addition, human adipose-derived mesenchymal stem cells were cultured on the scaffolds to evaluate the effect of pore morphology on cell proliferation and gene expression. Biphasic scaffolds supported cell attachment and influenced cytoskeleton organization depending on pore alignment. In addition, the gene expression of tendon/ligament, enthesis, and cartilage markers significantly changed depending on pore alignment in each region of the scaffolds. In conclusion, the biphasic scaffolds fabricated in this study show promising features for tendon/ligament-to-bone tissue engineering.
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Affiliation(s)
- Sònia Font Tellado
- 1 Department of Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich , Munich, Germany
| | - Walter Bonani
- 2 Department of Industrial Engineering, BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento , Trento, Italy .,3 Trento Research Unit, INSTM-National Interuniversity Consortium of Materials Science and Technology , Trento, Italy
| | - Elizabeth R Balmayor
- 1 Department of Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich , Munich, Germany
| | - Peter Foehr
- 4 Department of Orthopaedics and Sports Orthopaedics, Klinikum rechts der Isar, Technical University of Munich , Munich, Germany
| | - Antonella Motta
- 2 Department of Industrial Engineering, BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento , Trento, Italy
| | - Claudio Migliaresi
- 2 Department of Industrial Engineering, BIOtech Research Center and European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Trento , Trento, Italy .,3 Trento Research Unit, INSTM-National Interuniversity Consortium of Materials Science and Technology , Trento, Italy
| | - Martijn van Griensven
- 1 Department of Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich , Munich, Germany
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120
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Huang AH. Coordinated development of the limb musculoskeletal system: Tendon and muscle patterning and integration with the skeleton. Dev Biol 2017; 429:420-428. [PMID: 28363737 DOI: 10.1016/j.ydbio.2017.03.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 03/16/2017] [Accepted: 03/27/2017] [Indexed: 12/14/2022]
Abstract
Functional movement and stability of the limb depends on an organized and fully integrated musculoskeletal system composed of skeleton, muscle, and tendon. Much of our current understanding of musculoskeletal development is based on studies that focused on the development and differentiation of individual tissues. Likewise, research on patterning events have been largely limited to the primary skeletal elements and the mechanisms that regulate soft tissue patterning, the development of the connections between tissues, and their interdependent development are only beginning to be elucidated. This review will therefore highlight recent exciting discoveries in this field, with an emphasis on tendon and muscle patterning and their integrated development with the skeleton and skeletal attachments.
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Affiliation(s)
- Alice H Huang
- Icahn School of Medicine at Mount Sinai, Department of Orthopaedics, 1 Gustave Levy Place, Box 1188, New York, NY 10029, United States.
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121
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Scleraxis is required for maturation of tissue domains for proper integration of the musculoskeletal system. Sci Rep 2017; 7:45010. [PMID: 28327634 PMCID: PMC5361204 DOI: 10.1038/srep45010] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 02/20/2017] [Indexed: 12/17/2022] Open
Abstract
Scleraxis (Scx) is a basic helix-loop-helix transcription factor that is expressed persistently in tendons/ligaments, but transiently in entheseal cartilage. In this study, we generated a novel ScxCre knock-in (KI) allele, by in-frame replacement of most of Scx exon 1 with Cre recombinase (Cre), to drive Cre expression using Scx promoter and to inactivate the endogenous Scx. Reflecting the intensity and duration of endogenous expression, Cre-mediated excision occurs in tendinous and ligamentous tissues persistently expressing Scx. Expression of tenomodulin, a marker of mature tenocytes and ligamentocytes, was almost absent in tendons and ligaments of ScxCre/Cre KI mice lacking Scx to indicate defective maturation. In homozygotes, the transiently Scx-expressing entheseal regions such as the rib cage, patella cartilage, and calcaneus were small and defective and cartilaginous tuberosity was missing. Decreased Sox9 expression and phosphorylation of Smad1/5 and Smad3 were also observed in the developing entheseal cartilage, patella, and deltoid tuberosity of ScxCre/Cre KI mice. These results highlighted the functional importance of both transient and persistent expression domains of Scx for proper integration of the musculoskeletal components.
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122
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Grier W, Moy A, Harley B. Cyclic tensile strain enhances human mesenchymal stem cell Smad 2/3 activation and tenogenic differentiation in anisotropic collagen-glycosaminoglycan scaffolds. Eur Cell Mater 2017; 33:227-239. [PMID: 28319248 PMCID: PMC5453510 DOI: 10.22203/ecm.v033a14] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Stem cell research arose from the need to explore new therapeutic possibilities for intractable and lethal diseases. Although musculoskeletal disorders are basically nonlethal, their high prevalence and relative ease of performing clinical trials have facilitated the clinical application of stem cells in this field. However, few reliable clinical studies have been published, despite the plethora of in vitro and preclinical studies in stem cell research for regenerative medicine in the musculoskeletal system. Stem cell therapy can be applied locally for bone, cartilage and tendon regeneration. Candidate disease modalities in bone regeneration include large bone defects, nonunion of fractures, and osteonecrosis. Focal osteochondral defect and osteoarthritis are current targets for cartilage regeneration. For tendon regeneration, bone-tendon junction problems such as rotator cuff tears are hot topics in clinical research. To date, the literature supporting stem cell-based therapies comprises mostly case reports or case series. Therefore, high-quality evidence, including from randomised clinical trials, is necessary to define the role of cell-based therapies in the treatment of musculoskeletal disorders. It is imperative that clinicians who adopt stem cell treatment into their practices possess a good understanding of the natural course of the disease. It is also highly recommended that treating physicians do not thrust aside the concomitant use of established measures until stem cell therapy is evidently proved worthy in terms of efficacy and cost. The purpose of this review is to summarise on the current status of stem cell application in the orthopaedic field along with the author's view of future prospects.
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Affiliation(s)
- W.K. Grier
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - A.S. Moy
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - B.A.C. Harley
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA,Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA,Address for correspondence: B.A.C. Harley, Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 110 Roger Adams Laboratory, 600 S. Mathews Ave, Urbana, IL 61801, USA, Telephone number: +1 2172447112, Fax number: +1 2173335052,
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123
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Remédio L, Gribble KD, Lee JK, Kim N, Hallock PT, Delestrée N, Mentis GZ, Froemke RC, Granato M, Burden SJ. Diverging roles for Lrp4 and Wnt signaling in neuromuscular synapse development during evolution. Genes Dev 2017; 30:1058-69. [PMID: 27151977 PMCID: PMC4863737 DOI: 10.1101/gad.279745.116] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 03/31/2016] [Indexed: 11/25/2022]
Abstract
In this study, Remédio et al. use mice and zebrafish to show that muscle prepatterning in mammals and zebrafish is established by different mechanisms. Their findings demonstrate that Agrin/Lrp4/MuSK signaling plays an essential role in neuromuscular synapse formation in both fish and mammals, whereas Wnt signaling is dispensable. Motor axons approach muscles that are prepatterned in the prospective synaptic region. In mice, prepatterning of acetylcholine receptors requires Lrp4, a LDLR family member, and MuSK, a receptor tyrosine kinase. Lrp4 can bind and stimulate MuSK, strongly suggesting that association between Lrp4 and MuSK, independent of additional ligands, initiates prepatterning in mice. In zebrafish, Wnts, which bind the Frizzled (Fz)-like domain in MuSK, are required for prepatterning, suggesting that Wnts may contribute to prepatterning and neuromuscular development in mammals. We show that prepatterning in mice requires Lrp4 but not the MuSK Fz-like domain. In contrast, prepatterning in zebrafish requires the MuSK Fz-like domain but not Lrp4. Despite these differences, neuromuscular synapse formation in zebrafish and mice share similar mechanisms, requiring Lrp4, MuSK, and neuronal Agrin but not the MuSK Fz-like domain or Wnt production from muscle. Our findings demonstrate that evolutionary divergent mechanisms establish muscle prepatterning in zebrafish and mice.
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Affiliation(s)
- Leonor Remédio
- Molecular Neurobiology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University Medical School, New York, New York 10016, USA
| | - Katherine D Gribble
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Jennifer K Lee
- Molecular Neurobiology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University Medical School, New York, New York 10016, USA
| | - Natalie Kim
- Molecular Neurobiology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University Medical School, New York, New York 10016, USA
| | - Peter T Hallock
- Molecular Neurobiology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University Medical School, New York, New York 10016, USA
| | - Nicolas Delestrée
- Center for Motor Neuron Biology and Disease, Columbia University, New York, New York 10032, USA; Department of Pathology and Cell Biology, Columbia University, New York, New York 10032, USA; Department of Neurology, Columbia University, New York, New York 10032, USA
| | - George Z Mentis
- Center for Motor Neuron Biology and Disease, Columbia University, New York, New York 10032, USA; Department of Pathology and Cell Biology, Columbia University, New York, New York 10032, USA; Department of Neurology, Columbia University, New York, New York 10032, USA
| | - Robert C Froemke
- Molecular Neurobiology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University Medical School, New York, New York 10016, USA
| | - Michael Granato
- Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Steven J Burden
- Molecular Neurobiology Program, Helen L. and Martin S. Kimmel Center for Biology and Medicine at the Skirball Institute of Biomolecular Medicine, New York University Medical School, New York, New York 10016, USA
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124
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Schwartz AG, Galatz LM, Thomopoulos S. Enthesis regeneration: a role for Gli1+ progenitor cells. Development 2017; 144:1159-1164. [PMID: 28219952 DOI: 10.1242/dev.139303] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 02/13/2017] [Indexed: 12/14/2022]
Abstract
The tendon enthesis originates from a specific pool of hedgehog-active Gli1+ progenitor cells that differentiate and produce mineralized fibrocartilage. The current study investigated the regenerative capacity of this cell population by comparing the responses of early postnatal and mature entheses to injury. Lineage tracing studies demonstrated that the original Gli1+ cell population had the capacity to heal immature entheses after injury, but this capacity was lost after the cells differentiated into mature fibrochondrocytes. To further examine the involvement of Gli1+ cells and hedgehog signaling in enthesis healing, Gli1 expression was examined via lineage tracing approaches and the effect of Smo deletion was examined in the injured entheses. Immature injured entheses retained high levels of Gli1 expression, a marker of hedgehog activation, consistent with non-injured controls. In contrast, injured mature entheses had few Gli1+ cells early in the healing process, with limited recovery of the cell population later in the healing process. These results suggest that the presence of activated hedgehog signaling in enthesis cells early in the healing process may enhance healing of enthesis injuries by mimicking developmental processes.
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Affiliation(s)
- Andrea G Schwartz
- Department of Orthopedic Surgery, Washington University, St. Louis, MO 63110, USA
| | - Leesa M Galatz
- Department of Orthopedic Surgery, Icahn School of Medicine at Mount Sinai Hospital, Mount Sinai Health System, New York, NY 10029, USA
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Columbia University, New York, NY 10032, USA .,Department of Biomedical Engineering, Columbia University, New York, NY 10032, USA
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125
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Harris SE, Rediske M, Neitzke R, Rakian A. Periodontal Biology: Stem Cells, Bmp2 Gene, Transcriptional Enhancers, and Use of Sclerostin Antibody and Pth for Treatment of Periodontal Disease and Bone Loss. CELL, STEM CELLS AND REGENERATIVE MEDICINE 2017; 3:10.16966/2472-6990.113. [PMID: 29457146 PMCID: PMC5813290 DOI: 10.16966/2472-6990.113] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The periodontium is a complex tissue with epithelial components and a complex set of mesodermal derived alveolar bone, cellular and a cellular cementum, and tendon like ligaments (PDL). The current evidence demonstrates that the major pool of periodontal stem cells is derived from a population of micro vascular associated aSMA-positive stem/progenitor (PSC) cells that by lineage tracing form all three major mesodermal derived components of the periodontium. With in vitro aSMA+ stem cells, transcriptome and chip- seq experiments, the gene network and enhancer maps were determined at several differentiation states of the PSC. Current work on the role of the Bmp2 gene in the periodontal stem cell differentiation demonstrated that this Wnt regulated gene, Bmp2, is necessary for differentiation to all three major mesodermal derived component of the periodontium. The mechanism and use of Sclerostin antibody as an activator of Wnt signaling and Bmp2 gene as a potential route to treat craniofacial bone loss is discussed. As well, the mechanism and use of Pth in the treatment of periodontal bone loss or other craniofacial bone loss is presented in this review.
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Affiliation(s)
- Stephen E Harris
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Michael Rediske
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Rebecca Neitzke
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Audrey Rakian
- Department of Periodontics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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126
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McKenzie JA, Buettmann E, Abraham AC, Gardner MJ, Silva MJ, Killian ML. Loss of scleraxis in mice leads to geometric and structural changes in cortical bone, as well as asymmetry in fracture healing. FASEB J 2016; 31:882-892. [PMID: 27864378 DOI: 10.1096/fj.201600969r] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/07/2016] [Indexed: 01/08/2023]
Abstract
Scleraxis (Scx) is a known regulator of tendon development, and recent work has identified the role of Scx in bone modeling. However, the role of Scx in fracture healing has not yet been explored. This study was conducted to identify the role of Scx in cortical bone development and fracture healing. Scx green fluorescent protein-labeled (ScxGFP) reporter and Scx-knockout (Scx-mutant) mice were used to assess bone morphometry and the effects of fracture healing on Scx localization and gene expression, as well as callus healing response. Botulinum toxin (BTX) was used to investigate muscle unloading effects on callus shape. Scx-mutant long bones had structural and mechanical defects. Scx gene expression was elevated and bmp4 was decreased at 24 h after fracture. ScxGFP+ cells were localized throughout the healing callus after fracture. Scx-mutant mice demonstrated disrupted callus healing and asymmetry. Asymmetry of Scx-mutant callus was not due to muscle unloading. Wild-type littermates (age matched) served as controls. This is the first study to explore the role of Scx in cortical bone mechanics and fracture healing. Deletion of Scx during development led to altered long bone properties and callus healing. This study also demonstrated that Scx may play a role in the periosteal response during fracture healing.-McKenzie, J. A., Buettmann, E., Abraham, A. C., Gardner, M. J., Silva, M. J., Killian, M. L. Loss of scleraxis in mice leads to geometric and structural changes in cortical bone, as well as asymmetry in fracture healing.
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Affiliation(s)
- Jennifer A McKenzie
- Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Evan Buettmann
- Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Adam C Abraham
- Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Michael J Gardner
- Department of Orthopedic Surgery, Stanford University, Redwood City, California, USA; and
| | - Matthew J Silva
- Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Megan L Killian
- Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, Missouri, USA; .,Department of Biomedical Engineering, University of Delaware, Newark, Delaware, USA
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127
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Abstract
Tendons are important components of our musculoskeletal system. Injuries to these tissues are very common, resulting from occupational-related injuries, sports-related trauma, and age-related degeneration. Unfortunately, there are few treatment options, and current therapies rarely restore injured tendons to their original function. An improved understanding of the pathways regulating their development and repair would have significant impact in stimulating the formulation of regenerative-based approaches for tendon injury. The zebrafish provides an ideal system in which to perform genetic and chemical screens to identify new pathways involved in tendon biology. Until recently, there had been few descriptions of tendons and ligaments in the zebrafish and their similarity to mammalian tendon tissues. In this chapter, we describe the development of the zebrafish tendon and ligament tissues in the context of their gene expression, structure, and interactions with neighboring musculoskeletal tissues. We highlight the similarities with tendon development in higher vertebrates, showing that the craniofacial tendons and ligaments in zebrafish morphologically, molecularly, and structurally resemble mammalian tendons and ligaments from embryonic to adult stages. We detail methods for fluorescent in situ hybridization and immunohistochemistry as an assay to examine morphological changes in the zebrafish musculoskeleton. Staining assays such as these could provide the foundation for screen-based approaches to identify new regulators of tendon development, morphogenesis, and repair. These discoveries would provide new targets and pathways to study in the context of regenerative medicine-based approaches to improve tendon healing.
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Affiliation(s)
- J W Chen
- Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States
| | - J L Galloway
- Massachusetts General Hospital, Boston, MA, United States; Harvard Medical School, Boston, MA, United States
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128
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Ghebes CA, van Lente J, Post JN, Saris DBF, Fernandes H. High-Throughput Screening Assay Identifies Small Molecules Capable of Modulating the BMP-2 and TGF-β1 Signaling Pathway. SLAS DISCOVERY 2016; 22:40-50. [PMID: 27628690 DOI: 10.1177/1087057116669346] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Modulating the bone morphogenetic protein 2 (BMP-2) and transforming growth factor-β1 (TGF-β1) signaling pathways is essential during tendon/ligament (T/L) healing. Unfortunately, growth factor delivery in situ is far from trivial and, in many cases, the necessary growth factors are not approved for clinical use. Here we used a BMP-2 and a TGF-β1 reporter cell line to screen a library of 1280 Food and Drug Administration-approved small molecules and identify modulators of both signaling pathways. We identified four compounds capable of modulating BMP and TGF signaling on primary human tendon-derived cells (huTCs) and describe their effects on proliferation and differentiation of these cells.
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Affiliation(s)
- Corina-Adriana Ghebes
- 1 MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Jéré van Lente
- 1 MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Janine Nicole Post
- 1 MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Daniel B F Saris
- 1 MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands.,2 Department of Orthopaedics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Hugo Fernandes
- 1 MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands.,3 Center for Neuroscience and Cell Biology (CNC), Stem Cells and Drug Screening Lab, University of Coimbra, Coimbra, Portugal
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129
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Havis E, Bonnin MA, Esteves de Lima J, Charvet B, Milet C, Duprez D. TGFβ and FGF promote tendon progenitor fate and act downstream of muscle contraction to regulate tendon differentiation during chick limb development. Development 2016; 143:3839-3851. [PMID: 27624906 DOI: 10.1242/dev.136242] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 08/25/2016] [Indexed: 01/02/2023]
Abstract
The molecular programme underlying tendon development has not been fully identified. Interactions with components of the musculoskeletal system are important for limb tendon formation. Limb tendons initiate their development independently of muscles; however, muscles are required for further tendon differentiation. We show that both FGF/ERK MAPK and TGFβ/SMAD2/3 signalling pathways are required and sufficient for SCX expression in chick undifferentiated limb cells, whereas the FGF/ERK MAPK pathway inhibits Scx expression in mouse undifferentiated limb mesodermal cells. During differentiation, muscle contraction is required to maintain SCX, TNMD and THBS2 expression in chick limbs. The activities of FGF/ERK MAPK and TGFβ/SMAD2/3 signalling pathways are decreased in tendons under immobilisation conditions. Application of FGF4 or TGFβ2 ligands prevents SCX downregulation in immobilised limbs. TGFβ2 but not FGF4 prevent TNMD and THBS2 downregulation under immobilisation conditions. We did not identify any intracellular crosstalk between both signalling pathways in their positive effect on SCX expression. Independently of each other, both FGF and TGFβ promote tendon commitment of limb mesodermal cells and act downstream of mechanical forces to regulate tendon differentiation during chick limb development.
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Affiliation(s)
- Emmanuelle Havis
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7622, Inserm U1156, IBPS-Developmental Biology Laboratory, Paris F-75005, France
| | - Marie-Ange Bonnin
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7622, Inserm U1156, IBPS-Developmental Biology Laboratory, Paris F-75005, France
| | - Joana Esteves de Lima
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7622, Inserm U1156, IBPS-Developmental Biology Laboratory, Paris F-75005, France
| | - Benjamin Charvet
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7622, Inserm U1156, IBPS-Developmental Biology Laboratory, Paris F-75005, France
| | - Cécile Milet
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7622, Inserm U1156, IBPS-Developmental Biology Laboratory, Paris F-75005, France
| | - Delphine Duprez
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7622, Inserm U1156, IBPS-Developmental Biology Laboratory, Paris F-75005, France
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130
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Grier WK, Iyoha EM, Harley BAC. The influence of pore size and stiffness on tenocyte bioactivity and transcriptomic stability in collagen-GAG scaffolds. J Mech Behav Biomed Mater 2016; 65:295-305. [PMID: 27614271 DOI: 10.1016/j.jmbbm.2016.08.034] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 01/31/2023]
Abstract
Orthopedic injuries, particularly those involving tendons and ligaments, are some of the most commonly treated musculoskeletal ailments, but are associated with high costs and poor outcomes. A significant barrier in the design of biomaterials for tendon tissue engineering is the rapid de-differentiation observed for primary tenocytes once removed from the tendon body. Herein, we evaluate the use of an anisotropic collagen-glycosaminoglycan (CG) scaffold as a tendon regeneration platform. We report the effects of structural properties of the scaffold (pore size, collagen fiber crosslinking density) on resultant tenocyte bioactivity, viability, and gene expression. In doing so we address a standing hypothesis that scaffold anisotropy and strut flexural rigidity (stiffness) co-regulate long-term maintenance of a tenocyte phenotype. We report changes in equine tenocyte specific gene expression profiles and bioactivity across a homologous series of anisotropic collagen scaffolds with defined changes in pore size and crosslinking density. Anisotropic scaffolds with higher crosslinking densities and smaller pore sizes were more able to resist cell-mediated contraction forces, promote increased tenocyte metabolic activity, and maintain and increase expression of tenogenic gene expression profiles. These results suggest that control over scaffold strut flexural rigidity via crosslinking and porosity provides an ideal framework to resolve structure-function maps relating the influence of scaffold anisotropy, stiffness, and nutrient biotransport on tenocyte-mediated scaffold remodeling and long-term phenotype maintenance.
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Affiliation(s)
- William K Grier
- Dept. of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ehiremen M Iyoha
- Dept. of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Brendan A C Harley
- Dept. of Chemical & Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
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131
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Colasanto MP, Eyal S, Mohassel P, Bamshad M, Bonnemann CG, Zelzer E, Moon AM, Kardon G. Development of a subset of forelimb muscles and their attachment sites requires the ulnar-mammary syndrome gene Tbx3. Dis Model Mech 2016; 9:1257-1269. [PMID: 27491074 PMCID: PMC5117227 DOI: 10.1242/dmm.025874] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 07/28/2016] [Indexed: 01/02/2023] Open
Abstract
In the vertebrate limb over 40 muscles are arranged in a precise pattern of attachment via muscle connective tissue and tendon to bone and provide an extensive range of motion. How the development of somite-derived muscle is coordinated with the development of lateral plate-derived muscle connective tissue, tendon and bone to assemble a functional limb musculoskeletal system is a long-standing question. Mutations in the T-box transcription factor, TBX3, have previously been identified as the genetic cause of ulnar-mammary syndrome (UMS), characterized by distinctive defects in posterior forelimb bones. Using conditional mutagenesis in mice, we now show that TBX3 has a broader role in limb musculoskeletal development. TBX3 is not only required for development of posterior forelimb bones (ulna and digits 4 and 5), but also for a subset of posterior muscles (lateral triceps and brachialis) and their bone eminence attachment sites. TBX3 specification of origin and insertion sites appears to be tightly linked with whether these particular muscles develop and may represent a newly discovered mechanism for specification of anatomical muscles. Re-examination of an individual with UMS reveals similar previously unrecognized muscle and bone eminence defects and indicates a conserved role for TBX3 in regulating musculoskeletal development. Summary: The ulnar-mammary syndrome (UMS) gene, Tbx3, is required for development of posterior forelimb bones, muscles and their attachment sites. This broadens the UMS phenotype and suggests a new muscle-specification model.
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Affiliation(s)
- Mary P Colasanto
- Department of Human Genetics, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA
| | - Shai Eyal
- Department of Molecular Genetics, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Payam Mohassel
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institutes of Health, Building 35, Room 2A-116, MSC 3705, 35 Convent Drive, Bethesda, MD 20892-3705, USA
| | - Michael Bamshad
- University of Washington School of Medicine, Department of Pediatrics, Division of Genetic Medicine, 1959 NE Pacific Street HSB I-607-F, Seattle, WA 98195-7371, USA
| | - Carsten G Bonnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institutes of Health, Building 35, Room 2A-116, MSC 3705, 35 Convent Drive, Bethesda, MD 20892-3705, USA
| | - Elazar Zelzer
- Department of Molecular Genetics, Weizmann Institute of Science, 234 Herzl Street, Rehovot 76100, Israel
| | - Anne M Moon
- Weis Center for Research, Geisinger Clinic, 100 North Academy Avenue, Danville, PA 17822, USA
| | - Gabrielle Kardon
- Department of Human Genetics, University of Utah, 15 North 2030 East, Salt Lake City, UT 84112, USA
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132
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Shwartz Y, Viukov S, Krief S, Zelzer E. Joint Development Involves a Continuous Influx of Gdf5-Positive Cells. Cell Rep 2016; 15:2577-87. [PMID: 27292641 PMCID: PMC4920976 DOI: 10.1016/j.celrep.2016.05.055] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/28/2016] [Accepted: 05/15/2016] [Indexed: 11/20/2022] Open
Abstract
Synovial joints comprise several tissue types, including articular cartilage, the capsule, and ligaments. All of these compartments are commonly assumed to originate from an early set of Gdf5-expressing progenitors populating the interzone domain. Here, we provide evidence that joints develop through a continuous influx of cells into the interzone, where they contribute differentially to forming joint tissues. Using a knockin Gdf5-CreER(T2) mouse, we show that early labeling of Gdf5-positive interzone cells failed to mark the entire organ. Conversely, multiple Cre activation steps indicated a contribution of these cells to various joint compartments later in development. Spatiotemporal differences between Gdf5 and tdTomato reporter expression support the notion of a continuous recruitment process. Finally, differential contribution of Gdf5-positive cells to various tissues suggests that the spatiotemporal dynamics of Gdf5 expression may instruct lineage divergence. This work supports the influx model of joint development, which may apply to other organogenic processes.
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Affiliation(s)
- Yulia Shwartz
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sergey Viukov
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sharon Krief
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Elazar Zelzer
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
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133
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Kanazawa T, Gotoh M, Ohta K, Shiba N, Nakamura KI. Three-dimensional ultrastructural analysis of development at the supraspinatus insertion by using focused ion beam/scanning electron microscope tomography in rats. J Orthop Res 2016; 34:969-76. [PMID: 26599103 DOI: 10.1002/jor.23111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 11/20/2015] [Indexed: 02/04/2023]
Abstract
To obtain a successful outcome after rotator cuff repair, the repaired tendon must be biologically anchored to the bone. However, the histological structure at the repaired tendon-bone interface differs from that of the site of normal tendon insertion. Therefore, analyzing postnatal development in detail will contribute to understanding the repaired tendon-bone interface after rotator cuff repair. In this study, we analyzed postnatal development at the tendon-bone insertion in terms of temporal changes in SOX9/SCX expression and three-dimensional (3D) ultrastructure with FIB/SEM tomography, a new scanning electron microscopic method. Sixteen postnatal Sprague-Dawley rats were used for the study. One-, two-, three-, and four-week-old rats were sacrificed and both right and left shoulders were removed; eight normal supraspinatus tendon insertions were isolated for each time point. At each time point, four specimens were evaluated with fluorescent immunostaining for SOX9/SCX expression, and the remaining four specimens were evaluated with FIB/SEM tomography. Even in postnatal development, SOX9(+) /SCX(+) expression was observed at the tendon insertion; expression gradually decreased with postnatal development at the normal tendon insertion. In 3D ultrastructure, the morphology of the cells and the number/orientation of the cell processes drastically changed by postnatal week 4. The pattern of SOX9/SCX expression and 3D ultrastructural changes obtained in this study contribute to an understanding of the complicated development of normal tendon-bone insertion. Therefore, this study helps elucidate the pathophysiology of tendon-bone insertion, especially in cases of rotator cuff tear and repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:969-976, 2016.
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Affiliation(s)
- Tomonoshin Kanazawa
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine, 67 Asahi-machi, Kurume City, Fukuoka, 830-0011, Japan.,Department of Orthopaedic Surgery, Kurume University School of Medicine, 67 Asahi-machi, Fukuoka, Kurume City, Fukuoka, 830-0011, Japan
| | - Masafumi Gotoh
- Department of Orthopaedic Surgery, Kurume University School of Medicine, 67 Asahi-machi, Fukuoka, Kurume City, Fukuoka, 830-0011, Japan
| | - Keisuke Ohta
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine, 67 Asahi-machi, Kurume City, Fukuoka, 830-0011, Japan
| | - Naoto Shiba
- Department of Orthopaedic Surgery, Kurume University School of Medicine, 67 Asahi-machi, Fukuoka, Kurume City, Fukuoka, 830-0011, Japan
| | - Kei-Ichiro Nakamura
- Division of Microscopic and Development Anatomy, Department of Anatomy, Kurume University School of Medicine, 67 Asahi-machi, Kurume City, Fukuoka, 830-0011, Japan
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134
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Subramanian A, Schilling TF. Tendon development and musculoskeletal assembly: emerging roles for the extracellular matrix. Development 2016; 142:4191-204. [PMID: 26672092 DOI: 10.1242/dev.114777] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Tendons and ligaments are extracellular matrix (ECM)-rich structures that interconnect muscles and bones. Recent work has shown how tendon fibroblasts (tenocytes) interact with muscles via the ECM to establish connectivity and strengthen attachments under tension. Similarly, ECM-dependent interactions between tenocytes and cartilage/bone ensure that tendon-bone attachments form with the appropriate strength for the force required. Recent studies have also established a close lineal relationship between tenocytes and skeletal progenitors, highlighting the fact that defects in signals modulated by the ECM can alter the balance between these fates, as occurs in calcifying tendinopathies associated with aging. The dynamic fine-tuning of tendon ECM composition and assembly thus gives rise to the remarkable characteristics of this unique tissue type. Here, we provide an overview of the functions of the ECM in tendon formation and maturation that attempts to integrate findings from developmental genetics with those of matrix biology.
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Affiliation(s)
- Arul Subramanian
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697-2300, USA
| | - Thomas F Schilling
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697-2300, USA
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135
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Shukunami C, Yoshimoto Y, Takimoto A, Yamashita H, Hiraki Y. Molecular characterization and function of tenomodulin, a marker of tendons and ligaments that integrate musculoskeletal components. JAPANESE DENTAL SCIENCE REVIEW 2016; 52:84-92. [PMID: 28408960 PMCID: PMC5390337 DOI: 10.1016/j.jdsr.2016.04.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/16/2016] [Accepted: 04/01/2016] [Indexed: 01/14/2023] Open
Abstract
Tendons and ligaments are dense fibrous bands of connective tissue that integrate musculoskeletal components in vertebrates. Tendons connect skeletal muscles to the bone and function as mechanical force transmitters, whereas ligaments bind adjacent bones together to stabilize joints and restrict unwanted joint movement. Fibroblasts residing in tendons and ligaments are called tenocytes and ligamentocytes, respectively. Tenomodulin (Tnmd) is a type II transmembrane glycoprotein that is expressed at high levels in tenocytes and ligamentocytes, and is also present in periodontal ligament cells and tendon stem/progenitor cells. Tnmd is related to chondromodulin-1 (Chm1), a cartilage-derived angiogenesis inhibitor, and both Tnmd and Chm1 are expressed in the CD31− avascular mesenchyme. The conserved C-terminal hydrophobic domain of these proteins, which is characterized by the eight Cys residues to form four disulfide bonds, may have an anti-angiogenic function. This review highlights the molecular characterization and function of Tnmd, a specific marker of tendons and ligaments.
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Affiliation(s)
- Chisa Shukunami
- Department of Molecular Biology and Biochemistry, Division of Basic Life Sciences, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553, Japan
| | - Yuki Yoshimoto
- Department of Molecular Biology and Biochemistry, Division of Basic Life Sciences, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553, Japan
| | - Aki Takimoto
- Department of Cellular Differentiation, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
| | - Hiroshi Yamashita
- Department of Molecular Biology and Biochemistry, Division of Basic Life Sciences, Institute of Biomedical and Health Sciences, Hiroshima University, Hiroshima 734-8553, Japan
| | - Yuji Hiraki
- Department of Cellular Differentiation, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
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136
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Rockel JS, Yu C, Whetstone H, Craft AM, Reilly K, Ma H, Tsushima H, Puviindran V, Al-Jazrawe M, Keller GM, Alman BA. Hedgehog inhibits β-catenin activity in synovial joint development and osteoarthritis. J Clin Invest 2016; 126:1649-63. [PMID: 27018594 DOI: 10.1172/jci80205] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 02/11/2016] [Indexed: 12/21/2022] Open
Abstract
Both the WNT/β-catenin and hedgehog signaling pathways are important in the regulation of limb development, chondrocyte differentiation, and degeneration of articular cartilage in osteoarthritis (OA). It is not clear how these signaling pathways interact in interzone cell differentiation and synovial joint morphogenesis. Here, we determined that constitutive activation of hedgehog signaling specifically within interzone cells induces joint morphological changes by selectively inhibiting β-catenin-induced Fgf18 expression. Stabilization of β-catenin or treatment with FGF18 rescued hedgehog-induced phenotypes. Hedgehog signaling induced expression of a dominant negative isoform of TCF7L2 (dnTCF7L2) in interzone progeny, which may account for the selective regulation of β-catenin target genes observed. Knockdown of TCF7L2 isoforms in mouse chondrocytes rescued hedgehog signaling-induced Fgf18 downregulation, while overexpression of the human dnTCF7L2 orthologue (dnTCF4) in human chondrocytes promoted the expression of catabolic enzymes associated with OA. Similarly, expression of dnTCF4 in human chondrocytes positively correlated with the aggrecanase ADAMTS4. Consistent with our developmental findings, activation of β-catenin also attenuated hedgehog-induced or surgically induced articular cartilage degeneration in mouse models of OA. Thus, our results demonstrate that hedgehog inhibits selective β-catenin target gene expression to direct interzone progeny fates and articular cartilage development and disease. Moreover, agents that increase β-catenin activity have the potential to therapeutically attenuate articular cartilage degeneration as part of OA.
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137
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Zieba J, Forlenza KN, Khatra JS, Sarukhanov A, Duran I, Rigueur D, Lyons KM, Cohn DH, Merrill AE, Krakow D. TGFβ and BMP Dependent Cell Fate Changes Due to Loss of Filamin B Produces Disc Degeneration and Progressive Vertebral Fusions. PLoS Genet 2016; 12:e1005936. [PMID: 27019229 PMCID: PMC4809497 DOI: 10.1371/journal.pgen.1005936] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 02/24/2016] [Indexed: 12/02/2022] Open
Abstract
Spondylocarpotarsal synostosis (SCT) is an autosomal recessive disorder characterized by progressive vertebral fusions and caused by loss of function mutations in Filamin B (FLNB). FLNB acts as a signaling scaffold by linking the actin cytoskleteon to signal transduction systems, yet the disease mechanisms for SCT remain unclear. Employing a Flnb knockout mouse, we found morphologic and molecular evidence that the intervertebral discs (IVDs) of Flnb–/–mice undergo rapid and progressive degeneration during postnatal development as a result of abnormal cell fate changes in the IVD, particularly the annulus fibrosus (AF). In Flnb–/–mice, the AF cells lose their typical fibroblast-like characteristics and acquire the molecular and phenotypic signature of hypertrophic chondrocytes. This change is characterized by hallmarks of endochondral-like ossification including alterations in collagen matrix, expression of Collagen X, increased apoptosis, and inappropriate ossification of the disc tissue. We show that conversion of the AF cells into chondrocytes is coincident with upregulated TGFβ signaling via Smad2/3 and BMP induced p38 signaling as well as sustained activation of canonical and noncanonical target genes p21 and Ctgf. These findings indicate that FLNB is involved in attenuation of TGFβ/BMP signaling and influences AF cell fate. Furthermore, we demonstrate that the IVD disruptions in Flnb–/–mice resemble aging degenerative discs and reveal new insights into the molecular causes of vertebral fusions and disc degeneration. Whereas there is a large foundation of knowledge concerning skeletal formation and development, identifying the molecular changes behind Intervertebral Disc (IVD) aging and degeneration has been a challenge. The loss of Filamin B, a protein component of the cell’s cytoskeletal structure, gives rise to Spondylocarpotarsal Synostosis, a rare genetic disorder characterized by fusions of the vertebral bodies. Similarly, mice lacking the Filamin B protein show fusions of the vertebral bodies. We found that these fusions are caused by the early degeneration and eventual ossification of the IVDs. Our study demonstrates that this degeneration is caused by the increase in TGFβ and BMP activity, developmental pathways essential in bone and cartilage formation. These findings represent a significant step forward in our understanding of the molecular basis of IVD degeneration. as well as revealing filamin B’s role in TGFβ/BMP signaling regulation. Moreover, we demonstrate that the study of the rare disease spondylocarpotarsal synostosis in a model organism can uncover mechanisms underlying more common diseases. Finally, our findings provide a model system that will facilitate further discoveries regarding disc degeneration, which affects a significant proportion of the population.
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Affiliation(s)
- Jennifer Zieba
- Department of Human Genetics, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
| | - Kimberly Nicole Forlenza
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
| | - Jagteshwar Singh Khatra
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
| | - Anna Sarukhanov
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
| | - Ivan Duran
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
| | - Diana Rigueur
- Department of Molecular, Cell, and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America
| | - Karen M. Lyons
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
- Department of Molecular, Cell, and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America
| | - Daniel H. Cohn
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
- Department of Molecular, Cell, and Developmental Biology, University of California at Los Angeles, Los Angeles, California, United States of America
| | - Amy E. Merrill
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, California, United States of America
- Department of Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California, Los Angeles, California, United States of America
| | - Deborah Krakow
- Department of Human Genetics, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
- Department of Orthopaedic Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California, United States of America
- * E-mail:
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138
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Mechanobiology of TGFβ signaling in the skeleton. Matrix Biol 2016; 52-54:413-425. [PMID: 26877077 DOI: 10.1016/j.matbio.2016.02.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 02/05/2016] [Accepted: 02/08/2016] [Indexed: 12/12/2022]
Abstract
Physical and biochemical cues play fundamental roles in the skeleton at both the tissue and cellular levels. The precise coordination of these cues is essential for skeletal development and homeostasis, and disruption of this coordination can drive disease progression. The growth factor TGFβ is involved in both the regulation of and cellular response to the physical microenvironment. It is essential to summarize the current findings regarding the mechanisms by which skeletal cells integrate physical and biochemical cues so that we can identify and address remaining gaps that could ultimately improve skeletal health. In this review, we describe the role of TGFβ in mechanobiological signaling in bone and cartilage at the tissue and cellular levels. We provide detail on how static and dynamic physical cues at the macro-level are transmitted to the micro-level, ultimately leading to regulation at each level of the TGFβ pathway and to cell differentiation. The continued integration of engineering and biological approaches is needed to answer many remaining questions, such as the mechanisms by which cells generate a coordinated response to physical and biochemical cues. We propose one such mechanism, through which the combination of TGFβ and an optimal physical microenvironment leads to synergistic induction of downstream TGFβ signaling.
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139
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Cell Signaling in Tenocytes: Response to Load and Ligands in Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 920:79-95. [DOI: 10.1007/978-3-319-33943-6_7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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140
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Wang M, Nasiri AR, Broadus AE, Tommasini SM. Periosteal PTHrP Regulates Cortical Bone Remodeling During Fracture Healing. Bone 2015; 81:104-111. [PMID: 26164475 PMCID: PMC4641003 DOI: 10.1016/j.bone.2015.07.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 06/15/2015] [Accepted: 07/06/2015] [Indexed: 11/16/2022]
Abstract
Parathyroid hormone-related protein (PTHrP) is widely expressed in the fibrous outer layer of the periosteum (PO), and the PTH/PTHrP type I receptor (PTHR1) is expressed in the inner PO cambial layer. The cambial layer gives rise to the PO osteoblasts (OBs) and osteoclasts (OCs) that model/remodel the cortical bone surface during development as well as during fracture healing. PTHrP has been implicated in the regulation of PO modeling during development, but nothing is known as regards a role of PTHrP in this location during fracture healing. We propose that PTHrP in the fibrous layer of the PO may be a key regulatory factor in remodeling bone formation during fracture repair. We first assessed whether PTHrP expression in the fibrous PO is associated with PO osteoblast induction in the subjacent cambial PO using a tibial fracture model in PTHrP-lacZ mice. Our results revealed that both PTHrP expression and osteoblast induction in PO were induced 3 days post-fracture. We then investigated a potential functional role of PO PTHrP during fracture repair by performing tibial fracture surgery in 10-week-old CD1 control and PTHrP conditional knockout (PTHrP cKO) mice that lack PO PTHrP. We found that callus size and formation as well as woven bone mineralization in PTHrP cKO mice were impaired compared to that in CD1 mice. Concordant with these findings, functional enzyme staining revealed impaired OB formation and OC activity in the cKO mice. We conclude that deleting PO PTHrP impairs cartilaginous callus formation, maturation and ossification as well as remodeling during fracture healing. These data are the initial genetic evidence suggesting that PO PTHrP may induce osteoblastic activity and regulate fracture healing on the cortical bone surface.
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Affiliation(s)
- Meina Wang
- Department of Orthopaedics and Rehabilitation, Yale University, New Haven, CT 06520, USA; Department of Internal Medicine, Yale University, New Haven, CT 06520, USA.
| | - Ali R Nasiri
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA.
| | - Arthur E Broadus
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA.
| | - Steven M Tommasini
- Department of Orthopaedics and Rehabilitation, Yale University, New Haven, CT 06520, USA.
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141
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Regan JN, Waning DL, Guise TA. Skeletal muscle Ca(2+) mishandling: Another effect of bone-to-muscle signaling. Semin Cell Dev Biol 2015; 49:24-9. [PMID: 26593325 DOI: 10.1016/j.semcdb.2015.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 11/13/2015] [Indexed: 01/06/2023]
Abstract
Our appreciation of crosstalk between muscle and bone has recently expanded beyond mechanical force-driven events to encompass a variety of signaling factors originating in one tissue and communicating to the other. While the recent identification of new 'myokines' has shifted some focus to the role of muscle in this partnership, bone-derived factors and their effects on skeletal muscle should not be overlooked. This review summarizes some previously known mediators of bone-to-muscle signaling and also recent work identifying a new role for bone-derived TGF-β as a cause of skeletal muscle weakness in the setting of cancer-induced bone destruction. Oxidation of the ryanodine receptor/calcium release channel (RyR1) in skeletal muscle occurs via a TGF-β-Nox4-RyR1 axis and leads to calcium mishandling and decreased muscle function. Multiple points of potential therapeutic intervention were identified, from preventing the bone destruction to stabilizing the RYR1 calcium channel. This new data reinforces the concept that bone can be an important source of signaling factors in pathphysiological settings.
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Affiliation(s)
- Jenna N Regan
- Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - David L Waning
- Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Theresa A Guise
- Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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142
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Anthwal N, Peters H, Tucker AS. Species-specific modifications of mandible shape reveal independent mechanisms for growth and initiation of the coronoid. EvoDevo 2015; 6:35. [PMID: 26568815 PMCID: PMC4644282 DOI: 10.1186/s13227-015-0030-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/12/2015] [Indexed: 01/10/2023] Open
Abstract
Background The variation in mandibular morphology of mammals reflects specialisations for different diets. Omnivorous and carnivorous mammals posses large mandibular coronoid processes, while herbivorous mammals have proportionally smaller or absent coronoids. This is correlated with the relative size of the temporalis muscle that forms an attachment to the coronoid process. The role of this muscle attachment in the development of the variation of the coronoid is unclear. Results By comparative developmental biology and mouse knockout studies, we demonstrate here that the initiation and growth of the coronoid are two independent processes, with initiation being intrinsic to the ossifying bone and growth dependent upon the extrinsic effect of muscle attachment. A necessary component of the intrinsic patterning is identified as the paired domain transcription factor Pax9. We also demonstrate that Sox9 plays a role independent of chondrogenesis in the growth of the coronoid process in response to muscle interaction. Conclusions The mandibular coronoid process is initiated by intrinsic factors, but later growth is dependent on extrinsic signals from the muscle. These extrinsic influences are hypothesised to be the basis of the variation in coronoid length seen across the mammalian lineage.
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Affiliation(s)
- Neal Anthwal
- Department of Craniofacial Development and Stem Cell Biology, Dental Institute, King's College London, London, SE1 9RT UK
| | - Heiko Peters
- Institute of Genetic Medicine, International Centre for Life, Newcastle University, Newcastle upon Tyne, NE1 3BZ UK
| | - Abigail S Tucker
- Department of Craniofacial Development and Stem Cell Biology, Dental Institute, King's College London, London, SE1 9RT UK
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143
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Abstract
The development of the vertebrate skeleton reflects its evolutionary history. Cartilage formation came before biomineralization and a head skeleton evolved before the formation of axial and appendicular skeletal structures. This review describes the processes that result in endochondral and intramembranous ossification, the important roles of growth and transcription factors, and the consequences of mutations in some of the genes involved. Following a summary of the origin of cartilage, muscle, and tendon cell lineages in the axial skeleton, we discuss the role of muscle forces in the formation of skeletal architecture and assembly of musculoskeletal functional units. Finally, ontogenetic patterning of bones in response to mechanical loading is reviewed.This article is part of a Special Issue entitled "Muscle Bone Interactions".
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Affiliation(s)
- Agnes D Berendsen
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard University, USA
| | - Bjorn R Olsen
- Department of Developmental Biology, Harvard School of Dental Medicine, Harvard University, USA.
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144
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Abstract
Muscle and bone are two intimately connected tissues. A coordinated interplay between these tissues at mechanical levels is required for their development, function and ageing. Evidence is emerging that several genes and molecular pathways exert a pleiotropic effect on both muscle and bone. Bone morphogenetic proteins (BMPs) are secreted signal factors belonging to the transforming growth factor β (TGFβ) superfamily. BMPs have an essential role during bone and cartilage formation and maintenance. Recently, we and others have demonstrated that the BMP pathway also has a role in controlling adult skeletal muscle mass. Thus, BMPs become crucial regulators of both bone and muscle formation and homeostasis. In this review we will discuss the signalling downstream BMP and its role in muscle-bone interaction. This article is part of a Special Issue entitled "Muscle Bone Interactions".
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Affiliation(s)
- Roberta Sartori
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, 35129 Padova, Italy; Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy.
| | - Marco Sandri
- Dulbecco Telethon Institute, Venetian Institute of Molecular Medicine, 35129 Padova, Italy; Department of Biomedical Sciences, University of Padova, 35121 Padova, Italy; Telethon Institute of Genetics and Medicine (TIGEM), 80131 Napoli, Italy.
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145
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Killian ML, Thomopoulos S. Scleraxis is required for the development of a functional tendon enthesis. FASEB J 2015; 30:301-11. [PMID: 26443819 DOI: 10.1096/fj.14-258236] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 09/08/2015] [Indexed: 11/11/2022]
Abstract
The attachment of dissimilar materials is a major engineering challenge, yet this challenge is seemingly overcome in biology. This study aimed to determine how the transcription factor Scleraxis (Scx) influences the development and maturation of the tendon-to-bone attachment (enthesis). Mice with conditional knockout (cKO) for Scx (Scx(flx/-), Prx1Cre(+)) and wild-type [(WT) Scx(flx/+) or Scx(flx/flx)] littermates were killed at postnatal days 7-56 (P7-P56). Enthesis morphometry, histology, and collagen alignment were investigated throughout postnatal growth. Enthesis tensile mechanical properties were also assessed. Laser microdissection of distinct musculoskeletal tissues was performed at P7 for WT, cKO, and muscle-unloaded (botulinum toxin A treated) attachments for quantitative PCR. cKO mice were smaller, with altered bone shape and impaired enthesis morphology, morphometry, and organization. Structural alterations led to altered mechanical properties; cKO entheses demonstrated reduced strength and stiffness. In P7 attachments, cKO mice had reduced expression of transforming growth factor (TGF) superfamily genes in fibrocartilage compared with WT mice. In conclusion, deletion of Scx led to impairments in enthesis structure, which translated into impaired functional (i.e., mechanical) outcomes. These changes may be driven by transient signaling cues from mechanical loading and growth factors.
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Affiliation(s)
- Megan L Killian
- Department of Orthopedic Surgery, Washington University, St. Louis, Missouri, USA
| | - Stavros Thomopoulos
- Department of Orthopedic Surgery, Washington University, St. Louis, Missouri, USA
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146
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Abstract
Amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease, is a fatal neuromuscular disorder characterized by degeneration of motor neurons and by skeletal muscle atrophy. Although the death of motor neurons is a pathological hallmark of ALS, the potential role of other organs in disease progression remains to be elucidated. Skeletal muscle and bone are the two largest organs in the human body. They are responsible not only for locomotion but also for maintaining whole body normal metabolism and homeostasis. Patients with ALS display severe muscle atrophy, which may reflect intrinsic defects in mitochondrial respiratory function and calcium (Ca) signaling in muscle fibers, in addition to the role of axonal withdrawal associated with ALS progression. Incidence of fractures is high in ALS patients, indicating there are potential bone defects in individuals with this condition. There is a lifelong interaction between skeletal muscle and bone. The severe muscle degeneration that occurs during ALS progression may potentially have a significant impact on bone function, and the defective bone may also contribute significantly to neuromuscular degeneration in the course of the disease. Due to the nature of the rapid and severe neuromuscular symptoms, a majority of studies on ALS have focused on neurodegeneration. Just a few studies have explored the possible contribution of muscle defects, even fewer on bone defects, and fewer still on possible muscle-bone crosstalk in ALS. This review article discusses current studies on bone defects and potential defects in muscle-bone crosstalk in ALS.
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Affiliation(s)
- Jingsong Zhou
- Department of Physiology, Kansas City University of Medicine and Biosciences, 1750 Independence Ave., Kansas City, MO, 64106, USA,
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147
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Fan Y, Richelme S, Avazeri E, Audebert S, Helmbacher F, Dono R, Maina F. Tissue-Specific Gain of RTK Signalling Uncovers Selective Cell Vulnerability during Embryogenesis. PLoS Genet 2015; 11:e1005533. [PMID: 26393505 PMCID: PMC4579069 DOI: 10.1371/journal.pgen.1005533] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 08/25/2015] [Indexed: 12/04/2022] Open
Abstract
The successive events that cells experience throughout development shape their intrinsic capacity to respond and integrate RTK inputs. Cellular responses to RTKs rely on different mechanisms of regulation that establish proper levels of RTK activation, define duration of RTK action, and exert quantitative/qualitative signalling outcomes. The extent to which cells are competent to deal with fluctuations in RTK signalling is incompletely understood. Here, we employ a genetic system to enhance RTK signalling in a tissue-specific manner. The chosen RTK is the hepatocyte growth factor (HGF) receptor Met, an appropriate model due to its pleiotropic requirement in distinct developmental events. Ubiquitously enhanced Met in Cre/loxP-based Rosa26stopMet knock-in context (Del-R26Met) reveals that most tissues are capable of buffering enhanced Met-RTK signalling thus avoiding perturbation of developmental programs. Nevertheless, this ubiquitous increase of Met does compromise selected programs such as myoblast migration. Using cell-type specific Cre drivers, we genetically showed that altered myoblast migration results from ectopic Met expression in limb mesenchyme rather than in migrating myoblasts themselves. qRT-PCR analyses show that ectopic Met in limbs causes molecular changes such as downregulation in the expression levels of Notum and Syndecan4, two known regulators of morphogen gradients. Molecular and functional studies revealed that ectopic Met expression in limb mesenchyme does not alter HGF expression patterns and levels, but impairs HGF bioavailability. Together, our findings show that myoblasts, in which Met is endogenously expressed, are capable of buffering increased RTK levels, and identify mesenchymal cells as a cell type vulnerable to ectopic Met-RTK signalling. These results illustrate that embryonic cells are sensitive to alterations in the spatial distribution of RTK action, yet resilient to fluctuations in signalling levels of an RTK when occurring in its endogenous domain of activity. The need to achieve precise control of RTK activation is highlighted by human pathologies such as congenital malformations and cancers caused by aberrant RTK signalling. Identifying strategies to restrain RTK activity in cancer and/or to reactivate RTKs for counteracting degenerative processes is the focus of intense research efforts. We designed a genetic system to enhance RTK signalling during mouse embryogenesis in order to examine the competence of cells to deal with changes in RTK inputs. Our data reveal that most embryonic cells are capable of: 1) handling moderate perturbations in Met-RTK expression levels, 2) imposing a threshold of intracellular signalling activation despite elevated Met-RTK inputs, and/or 3) integrating variable quantitative levels of Met-RTK signalling within biological responses. Our results also establish that certain cell types, such as limb mesenchyme, are particularly vulnerable to alterations of the spatial distribution of RTK expression. The vulnerability of limb mesenchyme to enhanced Met levels is illustrated by gene expression changes, by interference with HGF chemoattractant effects, and by loss of accessibility to incoming myoblasts, leading to limb muscle defects. These findings highlight how resilience versus vulnerability to RTK fluctuation is strictly linked to cell competence and to the robustness of the developmental programs they undergo.
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Affiliation(s)
- Yannan Fan
- Aix-Marseille Université, CNRS, IBDM UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Sylvie Richelme
- Aix-Marseille Université, CNRS, IBDM UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Emilie Avazeri
- Aix-Marseille Université, CNRS, IBDM UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Stéphane Audebert
- Aix-Marseille Université UM 105, CNRS UMR7258, Inserm U1068, CRCM, Institut Paoli-Calmettes, Marseille, France
| | - Françoise Helmbacher
- Aix-Marseille Université, CNRS, IBDM UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Rosanna Dono
- Aix-Marseille Université, CNRS, IBDM UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
| | - Flavio Maina
- Aix-Marseille Université, CNRS, IBDM UMR 7288, Parc Scientifique de Luminy, Case 907, Marseille, France
- * E-mail:
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148
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Gaut L, Duprez D. Tendon development and diseases. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 5:5-23. [PMID: 26256998 DOI: 10.1002/wdev.201] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 06/15/2015] [Accepted: 06/20/2015] [Indexed: 12/22/2022]
Abstract
Tendon is a uniaxial connective tissue component of the musculoskeletal system. Tendon is involved in force transmission between muscle and bone. Tendon injury is very common and debilitating but tendon repair remains a clinical challenge for orthopedic medicine. In vertebrates, tendon is mainly composed of type I collagen fibrils, displaying a parallel organization along the tendon axis. The tendon-specific spatial organization of type I collagen provides the mechanical properties for tendon function. In contrast to other components of the musculoskeletal system, tendon biology is poorly understood. An important goal in tendon biology is to understand the mechanisms involved in the production and assembly of type I collagen fibrils during development, postnatal formation, and healing processes in order to design new therapies for tendon repair. In this review we highlight the current understanding of the molecular and mechanical signals known to be involved in tenogenesis during development, and how development provides insights into tendon healing processes. WIREs Dev Biol 2016, 5:5-23. doi: 10.1002/wdev.201 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Ludovic Gaut
- CNRS UMR 7622, IBPS-Developmental Biology Laboratory, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, IBPS-Developmental Biology Laboratory, Paris, France.,Inserm U1156, Paris, France
| | - Delphine Duprez
- CNRS UMR 7622, IBPS-Developmental Biology Laboratory, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, IBPS-Developmental Biology Laboratory, Paris, France.,Inserm U1156, Paris, France
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149
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Shea CA, Rolfe RA, Murphy P. The importance of foetal movement for co-ordinated cartilage and bone development in utero : clinical consequences and potential for therapy. Bone Joint Res 2015; 4:105-16. [PMID: 26142413 PMCID: PMC4602203 DOI: 10.1302/2046-3758.47.2000387] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Construction of a functional skeleton is accomplished
through co-ordination of the developmental processes of chondrogenesis,
osteogenesis, and synovial joint formation. Infants whose movement in
utero is reduced or restricted and who subsequently suffer
from joint dysplasia (including joint contractures) and thin hypo-mineralised
bones, demonstrate that embryonic movement is crucial for appropriate
skeletogenesis. This has been confirmed in mouse, chick, and zebrafish
animal models, where reduced or eliminated movement consistently yields
similar malformations and which provide the possibility of experimentation
to uncover the precise disturbances and the mechanisms by which
movement impacts molecular regulation. Molecular genetic studies have
shown the important roles played by cell communication signalling
pathways, namely Wnt, Hedgehog, and transforming growth factor-beta/bone
morphogenetic protein. These pathways regulate cell behaviours such
as proliferation and differentiation to control maturation of the
skeletal elements, and are affected when movement is altered. Cell
contacts to the extra-cellular matrix as well as the cytoskeleton
offer a means of mechanotransduction which could integrate mechanical
cues with genetic regulation. Indeed, expression of cytoskeletal
genes has been shown to be affected by immobilisation. In addition
to furthering our understanding of a fundamental aspect of cell control
and differentiation during development, research in this area is
applicable to the engineering of stable skeletal tissues from stem
cells, which relies on an understanding of developmental mechanisms
including genetic and physical criteria. A deeper understanding
of how movement affects skeletogenesis therefore has broader implications
for regenerative therapeutics for injury or disease, as well as
for optimisation of physical therapy regimes for individuals affected
by skeletal abnormalities. Cite this article: Bone Joint Res 2015;4:105–116
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Affiliation(s)
- C A Shea
- Trinity College Dublin, College Green, Dublin, D2, Ireland
| | | | - P Murphy
- Trinity College Dublin, College Green, Dublin, D2, Ireland
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150
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Lee JH, Pryce BA, Schweitzer R, Ryder MI, Ho SP. Differentiating zones at periodontal ligament-bone and periodontal ligament-cementum entheses. J Periodontal Res 2015; 50:870-80. [PMID: 26031604 DOI: 10.1111/jre.12281] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND OBJECTIVE The structural and functional integrity of bone-periodontal ligament (PDL)-cementum complex stems from the load-bearing attachment sites (entheses) between soft (PDL) and hard (bone, cementum) tissues. These attachment sites are responsible for the maintenance of a bone-PDL-cementum complex biomechanical function. The objective was to investigate changes in spatiotemporal expression of key biomolecules in developing and functionally active entheses. MATERIAL AND METHODS Multilabeling technique was performed on hemimandibles of 3 wk and 3 mo-old scleraxis-GFP transgenic mice for CD146, CD31, NG2, osterix and bone sialoprotein. Regions of dominant stretch within the PDL were evaluated by identifying directionality of collagen fibrils, PDL fibroblasts and PDL cell cytoskeleton. RESULTS CD146+ cells adjacent to CD31+ vasculature were identified at PDL-bone enthesis. NG2+ cells were located at coronal bone-PDL and apical cementum-PDL entheses in the 3-wk-old group, but at 3 mo, NG2 was positive at the entheses of the apical region and alveolar crest. NG2 and osterix were colocalized at the osteoid and cementoid regions of the PDL-bone and PDL-cementum entheses. Bone sialoprotein was prominent at the apical region of 3-wk-old mice. The directionality of collagen fibers, fibroblasts and their cytoskeleton overlapped, except in the apical region of 3 wk. CONCLUSION Colocalization of biomolecules at zones of the PDL adjacent to attachment sites may be essential for the formation of precementum and osteoid interfaces at a load-bearing bone-PDL-tooth fibrous joint. Biophysical cues resulting from development and function can regulate recruitment and differentiation of stem cells potentially from a vascular origin toward osteo- and cemento-blastic lineages at the PDL-bone and PDL-cementum entheses. Investigating the coupled effect of biophysical and biochemical stimuli leading to cell differentiation at the functional attachment sites is critical for developing regeneration strategies to enable functional reconstruction of the periodontal complex.
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Affiliation(s)
- J-H Lee
- Division of Biomaterials and Bioengineering, Department of Preventive and Restorative Dental Sciences, University of California at San Francisco, San Francisco, CA, USA
| | - B A Pryce
- Portland Shriner's Research Center, Oregon Health & Science University, Portland, OR, USA
| | - R Schweitzer
- Portland Shriner's Research Center, Oregon Health & Science University, Portland, OR, USA
| | - M I Ryder
- Division of Periodontology, Department of Orofacial Sciences, University of California at San Francisco, San Francisco, CA, USA
| | - S P Ho
- Division of Biomaterials and Bioengineering, Department of Preventive and Restorative Dental Sciences, University of California at San Francisco, San Francisco, CA, USA
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