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Heggli I, Teixeira GQ, Iatridis JC, Neidlinger‐Wilke C, Dudli S. The role of the complement system in disc degeneration and Modic changes. JOR Spine 2024; 7:e1312. [PMID: 38312949 PMCID: PMC10835744 DOI: 10.1002/jsp2.1312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 12/15/2023] [Accepted: 01/04/2024] [Indexed: 02/06/2024] Open
Abstract
Disc degeneration and vertebral endplate bone marrow lesions called Modic changes are prevalent spinal pathologies found in chronic low back pain patients. Their pathomechanisms are complex and not fully understood. Recent studies have revealed that complement system proteins and interactors are dysregulated in disc degeneration and Modic changes. The complement system is part of the innate immune system and plays a critical role in tissue homeostasis. However, its dysregulation has also been associated with various pathological conditions such as rheumatoid arthritis and osteoarthritis. Here, we review the evidence for the involvement of the complement system in intervertebral disc degeneration and Modic changes. We found that only a handful of studies reported on complement factors in Modic changes and disc degeneration. Therefore, the level of evidence for the involvement of the complement system is currently low. Nevertheless, the complement system is tightly intertwined with processes known to occur during disc degeneration and Modic changes, such as increased cell death, autoantibody production, bacterial defense processes, neutrophil activation, and osteoclast formation, indicating a contribution of the complement system to these spinal pathologies. Based on these mechanisms, we propose a model how the complement system could contribute to the vicious cycle of tissue damage and chronic inflammation in disc degeneration and Modic changes. With this review, we aim to highlight a currently understudied but potentially important inflammatory pathomechanism of disc degeneration and Modic changes that may be a novel therapeutic target.
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Affiliation(s)
- Irina Heggli
- Center of Experimental Rheumatology, Department of RheumatologyUniversity Hospital Zurich, University of ZurichZurichSwitzerland
- Department of Physical Medicine and RheumatologyBalgrist University Hospital, Balgrist Campus, University of ZurichZurichSwitzerland
- Leni and Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | - Graciosa Q. Teixeira
- Institute of Orthopedic Research and Biomechanics, Trauma Research Centre, Ulm UniversityUlmGermany
| | - James C. Iatridis
- Leni and Peter W. May Department of OrthopaedicsIcahn School of Medicine at Mount SinaiNew YorkNew YorkUSA
| | | | - Stefan Dudli
- Center of Experimental Rheumatology, Department of RheumatologyUniversity Hospital Zurich, University of ZurichZurichSwitzerland
- Department of Physical Medicine and RheumatologyBalgrist University Hospital, Balgrist Campus, University of ZurichZurichSwitzerland
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2
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Zou Z, Li H, Yu K, Ma K, Wang Q, Tang J, Liu G, Lim K, Hooper G, Woodfield T, Cui X, Zhang W, Tian K. The potential role of synovial cells in the progression and treatment of osteoarthritis. EXPLORATION (BEIJING, CHINA) 2023; 3:20220132. [PMID: 37933282 PMCID: PMC10582617 DOI: 10.1002/exp.20220132] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 06/15/2023] [Indexed: 11/08/2023]
Abstract
Osteoarthritis (OA), the commonest arthritis, is characterized by the progressive destruction of cartilage, leading to disability. The Current early clinical treatment strategy for OA often centers on anti-inflammatory or analgesia medication, weight loss, improved muscular function and articular cartilage repair. Although these treatments can relieve symptoms, OA tends to be progressive, and most patients require arthroplasty at the terminal stages of OA. Recent studies have shown a close correlation between joint pain, inflammation, cartilage destruction and synovial cells. Consequently, understanding the potential mechanisms associated with the action of synovial cells in OA could be beneficial for the clinical management of OA. Therefore, this review comprehensively describes the biological functions of synovial cells, the synovium, together with the pathological changes of synovial cells in OA, and the interaction between the cartilage and synovium, which is lacking in the present literature. Additionally, therapeutic approaches based on synovial cells for OA treatment are further discussed from a clinical perspective, highlighting a new direction in the treatment of OA.
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Affiliation(s)
- Zaijun Zou
- Department of Sports MedicineThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
| | - Han Li
- Department of Sports MedicineThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
| | - Kai Yu
- Department of Bone and JointCentral Hospital of Zhuang He CityDalianLiaoningChina
| | - Ke Ma
- Department of Clinical MedicineChina Medical UniversityShenyangLiaoningChina
| | - Qiguang Wang
- National Engineering Research Center for BiomaterialsSichuan UniversityChengduSichuanChina
| | - Junnan Tang
- Department of CardiologyThe First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenanChina
| | - Guozhen Liu
- School of MedicineThe Chinese University of Hong Kong (Shenzhen)ShenzhenGuangdongChina
| | - Khoon Lim
- Christchurch Regenerative Medicine and Tissue Engineering Group (CReaTE)Department of Orthopaedic Surgery and Musculoskeletal MedicineUniversity of OtagoChristchurchNew Zealand
| | - Gary Hooper
- Christchurch Regenerative Medicine and Tissue Engineering Group (CReaTE)Department of Orthopaedic Surgery and Musculoskeletal MedicineUniversity of OtagoChristchurchNew Zealand
| | - Tim Woodfield
- Christchurch Regenerative Medicine and Tissue Engineering Group (CReaTE)Department of Orthopaedic Surgery and Musculoskeletal MedicineUniversity of OtagoChristchurchNew Zealand
| | - Xiaolin Cui
- Department of Sports MedicineThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
- School of MedicineThe Chinese University of Hong Kong (Shenzhen)ShenzhenGuangdongChina
- Christchurch Regenerative Medicine and Tissue Engineering Group (CReaTE)Department of Orthopaedic Surgery and Musculoskeletal MedicineUniversity of OtagoChristchurchNew Zealand
| | - Weiguo Zhang
- Department of Sports MedicineThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
- Key Laboratory of Molecular Mechanisms for Repair and Remodeling of Orthopaedic DiseasesLiaoning ProvinceDalianLiaoningChina
| | - Kang Tian
- Department of Sports MedicineThe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoningChina
- Key Laboratory of Molecular Mechanisms for Repair and Remodeling of Orthopaedic DiseasesLiaoning ProvinceDalianLiaoningChina
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Proteomic Analysis of Synovial Fibroblasts and Articular Chondrocytes Co-Cultures Reveals Valuable VIP-Modulated Inflammatory and Degradative Proteins in Osteoarthritis. Int J Mol Sci 2021; 22:ijms22126441. [PMID: 34208590 PMCID: PMC8235106 DOI: 10.3390/ijms22126441] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 12/20/2022] Open
Abstract
Osteoarthritis (OA) is the most common musculoskeletal disorder causing a great disability and a reduction in the quality of life. In OA, articular chondrocytes (AC) and synovial fibroblasts (SF) release innate-derived immune mediators that initiate and perpetuate inflammation, inducing cartilage extracellular matrix (ECM) degradation. Given the lack of therapies for the treatment of OA, in this study, we explore biomarkers that enable the development of new therapeutical approaches. We analyze the set of secreted proteins in AC and SF co-cultures by stable isotope labeling with amino acids (SILAC). We describe, for the first time, 115 proteins detected in SF-AC co-cultures stimulated by fibronectin fragments (Fn-fs). We also study the role of the vasoactive intestinal peptide (VIP) in this secretome, providing new proteins involved in the main events of OA, confirmed by ELISA and multiplex analyses. VIP decreases proteins involved in the inflammatory process (CHI3L1, PTX3), complement activation (C1r, C3), and cartilage ECM degradation (DCN, CTSB and MMP2), key events in the initiation and progression of OA. Our results support the anti-inflammatory and anti-catabolic properties of VIP in rheumatic diseases and provide potential new targets for OA treatment.
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Galindo-Izquierdo M, Pablos Alvarez JL. Complement as a Therapeutic Target in Systemic Autoimmune Diseases. Cells 2021; 10:cells10010148. [PMID: 33451011 PMCID: PMC7828564 DOI: 10.3390/cells10010148] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 12/16/2022] Open
Abstract
The complement system (CS) includes more than 50 proteins and its main function is to recognize and protect against foreign or damaged molecular components. Other homeostatic functions of CS are the elimination of apoptotic debris, neurological development, and the control of adaptive immune responses. Pathological activation plays prominent roles in the pathogenesis of most autoimmune diseases such as systemic lupus erythematosus, antiphospholipid syndrome, rheumatoid arthritis, dermatomyositis, and ANCA-associated vasculitis. In this review, we will review the main rheumatologic autoimmune processes in which complement plays a pathogenic role and its potential relevance as a therapeutic target.
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Petrović T, Trbojević-Akmačić I. Lectin and Liquid Chromatography-Based Methods for Immunoglobulin (G) Glycosylation Analysis. EXPERIENTIA SUPPLEMENTUM (2012) 2021; 112:29-72. [PMID: 34687007 DOI: 10.1007/978-3-030-76912-3_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Immunoglobulin (Ig) glycosylation has been shown to dramatically affect its structure and effector functions. Ig glycosylation changes have been associated with different diseases and show a promising biomarker potential for diagnosis and prognosis of disease advancement. On the other hand, therapeutic biomolecules based on structural and functional features of Igs demand stringent quality control during the production process to ensure their safety and efficacy. Liquid chromatography (LC) and lectin-based methods are routinely used in Ig glycosylation analysis complementary to other analytical methods, e.g., mass spectrometry and capillary electrophoresis. This chapter covers analytical approaches based on LC and lectins used in low- and high-throughput N- and O-glycosylation analysis of Igs, with the focus on immunoglobulin G (IgG) applications. General principles and practical examples of the most often used LC methods for Ig purification are described, together with typical workflows for N- and O-glycan analysis on the level of free glycans, glycopeptides, subunits, or intact Igs. Lectin chromatography is a historical approach for the analysis of lectin-carbohydrate interactions and glycoprotein purification but is still being used as a valuable tool in Igs purification and glycan analysis. On the other hand, lectin microarrays have found their application in the rapid screening of glycan profiles on intact proteins.
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Affiliation(s)
- Tea Petrović
- Glycoscience Research Laboratory, Genos Ltd., Zagreb, Croatia
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Hayes AJ, Melrose J. Aggrecan, the Primary Weight-Bearing Cartilage Proteoglycan, Has Context-Dependent, Cell-Directive Properties in Embryonic Development and Neurogenesis: Aggrecan Glycan Side Chain Modifications Convey Interactive Biodiversity. Biomolecules 2020; 10:E1244. [PMID: 32867198 PMCID: PMC7564073 DOI: 10.3390/biom10091244] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/19/2020] [Accepted: 08/23/2020] [Indexed: 02/06/2023] Open
Abstract
This review examines aggrecan's roles in developmental embryonic tissues, in tissues undergoing morphogenetic transition and in mature weight-bearing tissues. Aggrecan is a remarkably versatile and capable proteoglycan (PG) with diverse tissue context-dependent functional attributes beyond its established role as a weight-bearing PG. The aggrecan core protein provides a template which can be variably decorated with a number of glycosaminoglycan (GAG) side chains including keratan sulphate (KS), human natural killer trisaccharide (HNK-1) and chondroitin sulphate (CS). These convey unique tissue-specific functional properties in water imbibition, space-filling, matrix stabilisation or embryonic cellular regulation. Aggrecan also interacts with morphogens and growth factors directing tissue morphogenesis, remodelling and metaplasia. HNK-1 aggrecan glycoforms direct neural crest cell migration in embryonic development and is neuroprotective in perineuronal nets in the brain. The ability of the aggrecan core protein to assemble CS and KS chains at high density equips cartilage aggrecan with its well-known water-imbibing and weight-bearing properties. The importance of specific arrangements of GAG chains on aggrecan in all its forms is also a primary morphogenetic functional determinant providing aggrecan with unique tissue context dependent regulatory properties. The versatility displayed by aggrecan in biodiverse contexts is a function of its GAG side chains.
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Affiliation(s)
- Anthony J Hayes
- Bioimaging Research Hub, Cardiff School of Biosciences, Cardiff University, Cardiff CF10 3AX, Wales, UK
| | - James Melrose
- Raymond Purves Laboratory, Institute of Bone and Joint Research, Kolling Institute of Medical Research, Northern Sydney Local Health District, Royal North Shore Hospital, St. Leonards 2065, NSW, Australia
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney 2052, NSW, Australia
- Sydney Medical School, Northern, The University of Sydney, Faculty of Medicine and Health at Royal North Shore Hospital, St. Leonards 2065, NSW, Australia
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Identifying effector molecules, cells, and cytokines of innate immunity in OA. Osteoarthritis Cartilage 2020; 28:532-543. [PMID: 32044352 DOI: 10.1016/j.joca.2020.01.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 01/29/2020] [Accepted: 01/30/2020] [Indexed: 02/06/2023]
Abstract
Inflammatory changes are observed in affected joints of osteoarthritis (OA) patients and are thought to be involved in the pathology that develops along OA progression. This narrative review provides an overview of the various cell types that are present in the joint during OA and which alarmins, cytokines, chemokines, growth factors, and other mediators they produce. Moreover, the involvement of more systemic processes like inflammaging and its associated cellular senescence in the context of OA are discussed.
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8
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Lubbers R, van Schaarenburg RA, Kwekkeboom JC, Levarht EWN, Bakker AM, Mahdad R, Monteagudo S, Cherifi C, Lories RJ, Toes REM, Ioan-Facsinay A, Trouw LA. Complement component C1q is produced by isolated articular chondrocytes. Osteoarthritis Cartilage 2020; 28:675-684. [PMID: 31634584 DOI: 10.1016/j.joca.2019.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 09/10/2019] [Accepted: 09/21/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Inflammation and innate immune responses may contribute to development and progression of Osteoarthritis (OA). Chondrocytes are the sole cell type of the articular cartilage and produce extracellular-matrix molecules. How inflammatory mediators reach chondrocytes is incompletely understood. Previous studies have shown that chondrocytes express mRNA encoding complement proteins such as C1q, suggesting local protein production, which has not been demonstrated conclusively. The aim of this study is to explore C1q production at the protein level by chondrocytes. DESIGN We analysed protein expression of C1q in freshly isolated and cultured human articular chondrocytes using Western blot, ELISA and flow cytometry. We examined changes in mRNA expression of collagen, MMP-1 and various complement genes upon stimulation with pro-inflammatory cytokines or C1q. mRNA expression of C1 genes was determined in articular mouse chondrocytes. RESULTS Primary human articular chondrocytes express genes encoding C1q, C1QA, C1QB, C1QC, and secrete C1q to the extracellular medium. Stimulation of chondrocytes with pro-inflammatory cytokines upregulated C1QA, C1QB, C1QC mRNA expression, although this was not confirmed at the protein level. Extracellular C1q bound to the chondrocyte surface dose dependently. In a pilot study, binding of C1q to chondrocytes resulted in changes in the expression of collagens with a decrease in collagen type 2 and an increase in type 10. Mouse articular chondrocytes also expressed C1QA, C1QB, C1QC, C1R and C1S at the mRNA level. CONCLUSIONS C1q protein can be expressed and secreted by human articular chondrocytes and is able to bind to chondrocytes influencing the relative collagen expression.
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Affiliation(s)
- R Lubbers
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands.
| | - R A van Schaarenburg
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands; Charles River, Leiden, the Netherlands
| | - J C Kwekkeboom
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands
| | - E W N Levarht
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands
| | - A M Bakker
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands
| | - R Mahdad
- Department of Orthopedic Surgery, Alrijne Hospital, Leiderdorp, the Netherlands
| | - S Monteagudo
- Laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| | - C Cherifi
- Laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| | - R J Lories
- Laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium; Division of Rheumatology, University Hospitals Leuven, Belgium
| | - R E M Toes
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands
| | - A Ioan-Facsinay
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands
| | - L A Trouw
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands; Department of Immunohematology and Blood Transfusion, Leiden University Medical, Center, Leiden, the Netherlands.
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Nicolas J, Magli S, Rabbachin L, Sampaolesi S, Nicotra F, Russo L. 3D Extracellular Matrix Mimics: Fundamental Concepts and Role of Materials Chemistry to Influence Stem Cell Fate. Biomacromolecules 2020; 21:1968-1994. [PMID: 32227919 DOI: 10.1021/acs.biomac.0c00045] [Citation(s) in RCA: 261] [Impact Index Per Article: 65.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Synthetic 3D extracellular matrices (ECMs) find application in cell studies, regenerative medicine, and drug discovery. While cells cultured in a monolayer may exhibit unnatural behavior and develop very different phenotypes and genotypes than in vivo, great efforts in materials chemistry have been devoted to reproducing in vitro behavior in in vivo cell microenvironments. This requires fine-tuning the biochemical and structural actors in synthetic ECMs. This review will present the fundamentals of the ECM, cover the chemical and structural features of the scaffolds used to generate ECM mimics, discuss the nature of the signaling biomolecules required and exploited to generate bioresponsive cell microenvironments able to induce a specific cell fate, and highlight the synthetic strategies involved in creating functional 3D ECM mimics.
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Affiliation(s)
- Julien Nicolas
- Université Paris-Saclay, CNRS, Institut Galien Paris-Saclay, , 92296 Châtenay-Malabry, France
| | - Sofia Magli
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Piazza della Scienza 2, 20126 Milan, Italy
| | - Linda Rabbachin
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Piazza della Scienza 2, 20126 Milan, Italy
| | - Susanna Sampaolesi
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Piazza della Scienza 2, 20126 Milan, Italy
| | - Francesco Nicotra
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Piazza della Scienza 2, 20126 Milan, Italy
| | - Laura Russo
- University of Milano-Bicocca, Department of Biotechnology and Biosciences, Piazza della Scienza 2, 20126 Milan, Italy
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10
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Complement activation and regulation in rheumatic disease. Semin Immunol 2019; 45:101339. [DOI: 10.1016/j.smim.2019.101339] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 10/24/2019] [Accepted: 10/24/2019] [Indexed: 01/02/2023]
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Rogerson FM, Last K, Golub SB, Gauci SJ, Stanton H, Bell KM, Fosang AJ. ADAMTS-9 in Mouse Cartilage Has Aggrecanase Activity That Is Distinct from ADAMTS-4 and ADAMTS-5. Int J Mol Sci 2019; 20:ijms20030573. [PMID: 30699963 PMCID: PMC6387038 DOI: 10.3390/ijms20030573] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/14/2019] [Accepted: 01/24/2019] [Indexed: 01/18/2023] Open
Abstract
A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS)-4 and ADAMTS-5 are the principal aggrecanases in mice and humans; however, mice lacking the catalytic domain of both enzymes (TS-4/5∆cat) have no skeletal phenotype, suggesting there is an alternative aggrecanase for modulating normal growth and development in these mice. We previously identified aggrecanase activity that (a) cleaved at E↓G rather than E↓A bonds in the aggrecan core protein, and (b) was upregulated by retinoic acid but not IL-1α. The present study aimed to identify the alternative aggrecanase. Femoral head cartilage explants from TS-4/5∆cat mice were stimulated with IL-1α or retinoic acid and total RNA was analysed by microarray. In addition to ADAMTS-5 and matrix metalloproteinase (MMP)-13, which are not candidates for the novel aggrecanase, the microarray analyses identified MMP-11, calpain-5 and ADAMTS-9 as candidate aggrecanases upregulated by retinoic acid. When calpain-5 and MMP-11 failed to meet subsequent criteria, ADAMTS-9 emerged as the most likely candidate for the novel aggrecanase. Immunohistochemistry revealed ADAMTS-9 expression throughout the mouse growth plate and strong expression, particularly in the proliferative zone of the TS-4/5-∆cat mice. In conclusion, ADAMTS-9 has a novel specificity for aggrecan, cleaving primarily at E↓G rather than E↓A bonds in mouse cartilage. ADAMTS-9 might have more important roles in normal skeletal development compared with ADAMTS-4 and ADAMTS-5, which have key roles in joint pathology.
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Affiliation(s)
- Fraser M Rogerson
- University of Melbourne Department of Paediatrics, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
- Royal Melbourne Institute of Technology, 124 La Trobe Street, Melbourne, Victoria 3000, Australia.
| | - Karena Last
- University of Melbourne Department of Paediatrics, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
| | - Suzanne B Golub
- University of Melbourne Department of Paediatrics, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
| | - Stephanie J Gauci
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
| | - Heather Stanton
- University of Melbourne Department of Paediatrics, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
| | - Katrina M Bell
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
| | - Amanda J Fosang
- University of Melbourne Department of Paediatrics, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
- Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Victoria 3052, Australia.
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Stephenson EL, Yong VW. Pro-inflammatory roles of chondroitin sulfate proteoglycans in disorders of the central nervous system. Matrix Biol 2018; 71-72:432-442. [PMID: 29702175 DOI: 10.1016/j.matbio.2018.04.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 04/21/2018] [Accepted: 04/21/2018] [Indexed: 02/06/2023]
Abstract
The extracellular matrix of the central nervous system is an interconnected network of proteins and sugars. It is crucial for homeostasis, but its remodeling in neurological diseases impacts both injury and repair. Here we introduce an extracellular matrix family member that participates in immune-matrix interactions, the chondroitin sulfate proteoglycans. Chondroitin sulfate proteoglycans integrate signals from the microenvironment to activate immune cells, and they boost inflammatory responses by binding immunological receptors including toll-like receptors, selectins, CD44, and β1 integrin. Chondroitin sulfate proteoglycans also bind signaling molecules for immune cells such as cytokines and chemokines, and they activate matrix-degrading enzymes. Chondroitin sulfate proteoglycans accumulate in the damaged CNS, including during traumatic brain/spinal cord injury and multiple sclerosis, and they help drive pathogenesis. This Review aims to give new insights into the remodeling of chondroitin sulfate proteoglycans during inflammation, and how these matrix glycoproteins are able to drive neuroinflammation.
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Affiliation(s)
- Erin L Stephenson
- Hotchkiss Brain Institute and the University of Calgary, Calgary, Alberta, Canada
| | - V Wee Yong
- Hotchkiss Brain Institute and the University of Calgary, Calgary, Alberta, Canada.
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13
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Silawal S, Triebel J, Bertsch T, Schulze-Tanzil G. Osteoarthritis and the Complement Cascade. CLINICAL MEDICINE INSIGHTS. ARTHRITIS AND MUSCULOSKELETAL DISORDERS 2018; 11:1179544117751430. [PMID: 29434479 PMCID: PMC5805003 DOI: 10.1177/1179544117751430] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/07/2017] [Indexed: 12/11/2022]
Abstract
Accumulating evidence demonstrates that complement activation is involved in the pathogenesis of osteoarthritis (OA). However, the intimate complement regulation and cross talk with other signaling pathways in joint-associated tissues remain incompletely understood. Recent insights are summarized and discussed here, to put together a more comprehensive picture of complement involvement in OA pathogenesis. Complement is regulated by several catabolic and inflammatory mediators playing a key role in OA. It seems to be involved in many processes observed during OA development and progression, such as extracellular cartilage matrix (ECM) degradation, chondrocyte and synoviocyte inflammatory responses, cell lysis, synovitis, disbalanced bone remodeling, osteophyte formation, and stem cell recruitment, as well as cartilage angiogenesis. In reverse, complement can be activated by various ECM components and their cleavage products, which are released during OA-associated cartilage degradation. There are, however, some other cartilage ECM components that can inhibit complement, underlining the diverse effects of ECM on the complement activation. It is hypothesized that complement might also be directly activated by mechanical stress, thereby contributing to OA. The question arises whether keeping the complement activation in balance could represent a future therapeutic strategy in OA treatment and in the prevention of its progression.
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Affiliation(s)
- Sandeep Silawal
- Department of Anatomy, Paracelsus Medical University, Nuremberg, Germany
- Institute of Anatomy, Paracelsus Medical University, Salzburg, Germany
| | - Jakob Triebel
- Institute for Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, Nuremberg General Hospital, Paracelsus Medical University, Nuremberg, Germany
| | - Thomas Bertsch
- Institute for Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, Nuremberg General Hospital, Paracelsus Medical University, Nuremberg, Germany
| | - Gundula Schulze-Tanzil
- Department of Anatomy, Paracelsus Medical University, Nuremberg, Germany
- Institute of Anatomy, Paracelsus Medical University, Salzburg, Germany
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14
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Abstract
PURPOSE OF THE REVIEW Mounting evidence supports a role of low-grade inflammation in the pathophysiology of osteoarthritis (OA). We review and discuss the role of synovitis, complement activation, cytokines, and immune cell population in OA. RECENT FINDINGS Using newer imaging modalities, synovitis is found in the majority of knees with OA. Complement activation and pro-inflammatory cytokines play a significant role in the development of cartilage destruction and synovitis. Immune cell infiltration of OA synovial tissue by sub-populations of T cells and activated macrophages correlates with OA disease progression and pain. The innate and acquired immune system plays a key role in the low-grade inflammation found associated with OA. Targets of these pathways my hold promise for future disease-modifying osteoarthritis drugs (DMOADs).
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Affiliation(s)
| | - Adrian Filiberti
- Department of Medicine, University of Oklahoma Health Sciences Center, 975 N.E. 10th St, BRC 256, Oklahoma City, OK, 73104, USA
| | - Syed Ali Husain
- Department of Medicine, University of Oklahoma Health Sciences Center, 975 N.E. 10th St, BRC 256, Oklahoma City, OK, 73104, USA
| | - Mary Beth Humphrey
- Department of Medicine, University of Oklahoma Health Sciences Center, 975 N.E. 10th St, BRC 256, Oklahoma City, OK, 73104, USA.
- Oklahoma City Veterans Affairs, Oklahoma City, OK, USA.
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15
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Lau D, Elezagic D, Hermes G, Mörgelin M, Wohl AP, Koch M, Hartmann U, Höllriegl S, Wagener R, Paulsson M, Streichert T, Klatt AR. The cartilage-specific lectin C-type lectin domain family 3 member A (CLEC3A) enhances tissue plasminogen activator-mediated plasminogen activation. J Biol Chem 2017; 293:203-214. [PMID: 29146595 DOI: 10.1074/jbc.m117.818930] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 11/03/2017] [Indexed: 01/25/2023] Open
Abstract
C-type lectin domain family 3 member A (CLEC3A) is a poorly characterized protein belonging to the superfamily of C-type lectins. Its closest homologue tetranectin binds to the kringle 4 domain of plasminogen and enhances its association with tissue plasminogen activator (tPA) thereby enhancing plasmin production, but whether CLEC3A contributes to plasminogen activation is unknown. Here, we recombinantly expressed murine and human full-length CLEC3As as well as truncated forms of CLEC3A in HEK-293 Epstein-Barr nuclear antigen (EBNA) cells. We analyzed the structure of recombinant CLEC3A by SDS-PAGE and immunoblot, glycan analysis, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, size-exclusion chromatography, circular dichroism spectroscopy, and electron microscopy; compared the properties of the recombinant protein with those of CLEC3A extracted from cartilage; and investigated its tissue distribution and extracellular assembly by immunohistochemistry and immunofluorescence microscopy. We found that CLEC3A mainly occurs as a monomer, but also forms dimers and trimers, potentially via a coiled-coil α-helix. We also noted that CLEC3A can be modified with chondroitin/dermatan sulfate side chains and tends to oligomerize to form higher aggregates. We show that CLEC3A is present in resting, proliferating, and hypertrophic growth-plate cartilage and assembles into an extended extracellular network in cultures of rat chondrosarcoma cells. Further, we found that CLEC3A specifically binds to plasminogen and enhances tPA-mediated plasminogen activation. In summary, we have determined the structure, tissue distribution, and molecular function of the cartilage-specific lectin CLEC3A and show that CLEC3A binds to plasminogen and participates in tPA-mediated plasminogen activation.
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Affiliation(s)
- Daniela Lau
- Institute for Clinical Chemistry, University of Cologne, D-50924 Cologne, Germany
| | - Dzemal Elezagic
- Institute for Clinical Chemistry, University of Cologne, D-50924 Cologne, Germany
| | - Gabriele Hermes
- Institute for Clinical Chemistry, University of Cologne, D-50924 Cologne, Germany
| | - Matthias Mörgelin
- Department of Clinical Sciences Lund, Division of Infection Medicine, Biomedical Center (BMC), Lund University, SE-221 00 Lund, Sweden
| | - Alexander P Wohl
- Center for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany
| | - Manuel Koch
- Center for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany; Institute for Dental Research and Oral Musculoskeletal Biology, Medical Faculty, University of Cologne, D-50931 Cologne, Germany
| | - Ursula Hartmann
- Center for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany
| | | | - Raimund Wagener
- Center for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, D-50931 Cologne, Germany
| | - Mats Paulsson
- Center for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany; Center for Molecular Medicine Cologne (CMMC), University of Cologne, D-50931 Cologne, Germany; Cologne Excellence Cluster on Cellular Stress Responses in Ageing-associated Diseases (CECAD), University of Cologne, D-50931 Cologne, Germany
| | - Thomas Streichert
- Institute for Clinical Chemistry, University of Cologne, D-50924 Cologne, Germany
| | - Andreas R Klatt
- Institute for Clinical Chemistry, University of Cologne, D-50924 Cologne, Germany.
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16
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Trouw LA, Pickering MC, Blom AM. The complement system as a potential therapeutic target in rheumatic disease. Nat Rev Rheumatol 2017; 13:538-547. [DOI: 10.1038/nrrheum.2017.125] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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17
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Vinatier C, Merceron C, Guicheux J. Osteoarthritis: from pathogenic mechanisms and recent clinical developments to novel prospective therapeutic options. Drug Discov Today 2016; 21:1932-1937. [PMID: 27616187 DOI: 10.1016/j.drudis.2016.08.011] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 07/28/2016] [Accepted: 08/30/2016] [Indexed: 11/24/2022]
Abstract
Osteoarthritis (OA) is a degenerative joint disease that, despite recent progress, has no curative treatment. Considerable research has recently been initiated to identify new potential therapeutic targets. In this review, we will set forth some of the major discoveries in the past 5 years, notably those dealing with the identification of pathogenic factors [hypoxia-inducible factors (HIFs), complement, transforming growth factor (TGF)-β and zinc-ZIP8]. New drugs and concepts currently in clinical development [anti-nerve growth factor (NGF), mesenchymal stromal cells and fibroblast growth factor (FGF)-18] will then be addressed. Finally, we will consider prospective avenues that could lead to mid-to-long-term developments of novel therapeutic concepts, notably those dealing with autophagy regulation and induced pluripotent stem cells.
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Affiliation(s)
- Claire Vinatier
- INSERM, UMRS 791-LIOAD, STEP Group, Nantes, France; Nantes University, UFR Odontology, Nantes, France
| | - Christophe Merceron
- INSERM, UMRS 791-LIOAD, STEP Group, Nantes, France; Nantes University, UFR Odontology, Nantes, France
| | - Jerome Guicheux
- INSERM, UMRS 791-LIOAD, STEP Group, Nantes, France; Nantes University, UFR Odontology, Nantes, France; CHU Nantes, PHU4 OTONN, Nantes, France.
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18
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Struglics A, Okroj M, Swärd P, Frobell R, Saxne T, Lohmander LS, Blom AM. The complement system is activated in synovial fluid from subjects with knee injury and from patients with osteoarthritis. Arthritis Res Ther 2016; 18:223. [PMID: 27716448 PMCID: PMC5052889 DOI: 10.1186/s13075-016-1123-x] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 09/16/2016] [Indexed: 01/13/2023] Open
Abstract
Background The complement system is suggested to be involved in the pathogenesis of osteoarthritis (OA), and proinflammatory cytokines may play a role in OA development by inducing proteases. The association between complement factors, cytokines and OA has not been investigated. The aim of the present study was to explore the involvement of the complement system after knee trauma and in OA. Methods C4d, C3bBbP and soluble terminal complement complex (sTCC) resulting from complement activation were immunoassayed in synovial fluid from subjects with healthy knees (reference), OA, rheumatoid arthritis (RA; positive control), pyrophosphate arthritis (PPA; positive control) and knee injury; other biomarkers were previously assessed. Magnetic resonance imaging was used to assess joint injuries. Results Compared with levels in the reference group, the median concentrations of C4d, C3bBbP and sTCC in the OA, RA, PPA and knee injury groups were 2- to 34-fold increased (p < 0.001 to p = 0.044). For the knee injury group, the median concentrations of C4d, C3bBbP and sTCC were 5- to 12-fold increased (p < 0.001) at the day of injury; after 3–12 weeks, C3bBbP and sTCC concentrations were similar to reference levels; and C4d was still increased several years after injury. In the 0–12 weeks period after injury, the concentrations of C4d, C3bBbP and sTCC correlated positively with levels of interleukin (IL)-1β, IL-6 and tumour necrosis factor α (rs range 0.232–0.547); none of the measured complement factors correlated with proteolytic fragments of aggrecan or cartilage oligomeric matrix protein. Knees with osteochondral fracture, with or without disrupted cortical bone, had higher concentrations of C4d (p = 0.014, p = 0.004) and sTCC (p = 0.004, p < 0.001) compared with knees without fractures. Conclusions The complement system is activated in OA and after knee injury. Following knee injury, this activation is instant and associated with inflammation as well as with the presence of osteochondral fractures. Electronic supplementary material The online version of this article (doi:10.1186/s13075-016-1123-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- André Struglics
- Department of Clinical Sciences Lund, Orthopaedics, Lund University, Faculty of Medicine, BMC C12, SE-221 84, Lund, Sweden.
| | - Marcin Okroj
- Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Faculty of Medicine, Lund, Sweden.,Department of Medical Biotechnology, Intercollegiate Faculty of Biotechnology UG-MUG, Medical University of Gdańsk, Gdańsk, Poland
| | - Per Swärd
- Department of Clinical Sciences Lund, Orthopaedics, Lund University, Faculty of Medicine, BMC C12, SE-221 84, Lund, Sweden
| | - Richard Frobell
- Department of Clinical Sciences Lund, Orthopaedics, Lund University, Faculty of Medicine, BMC C12, SE-221 84, Lund, Sweden
| | - Tore Saxne
- Department of Clinical Sciences Lund, Rheumatology, Lund University, Faculty of Medicine, Lund, Sweden
| | - L Stefan Lohmander
- Department of Clinical Sciences Lund, Orthopaedics, Lund University, Faculty of Medicine, BMC C12, SE-221 84, Lund, Sweden
| | - Anna M Blom
- Department of Translational Medicine, Division of Medical Protein Chemistry, Lund University, Faculty of Medicine, Lund, Sweden
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19
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Melin Fürst C, Åhrman E, Bratteby K, Waldemarson S, Malmström J, Blom AM. Quantitative Mass Spectrometry To Study Inflammatory Cartilage Degradation and Resulting Interactions with the Complement System. THE JOURNAL OF IMMUNOLOGY 2016; 197:3415-3424. [PMID: 27630166 DOI: 10.4049/jimmunol.1601006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/14/2016] [Indexed: 12/25/2022]
Abstract
Joint diseases are often characterized by inflammatory processes that result in pathological changes in joint tissues, including cartilage degradation and release of components into the synovial fluid. The complement system plays a central role in promoting the inflammation. Because several cartilage proteins are known to interact with complement, causing either activation or inhibition of the system, we aimed to investigate these interactions comprehensively. Bovine cartilage explants were cultured with IL-1α to induce cartilage degradation, followed by incubation with human serum. Label-free selected reaction monitoring mass spectrometry was used to specifically quantify complement proteins interacting with the cartilage explant. In parallel, the time-dependent degradation of cartilage was detected using mass spectrometry analysis (liquid chromatography-tandem mass spectrometry). Complement proteins resulting from activation of the classical, alternative, and terminal pathways were detected on IL-1α-stimulated cartilage at time points when clear alterations in extracellular matrix composition had occurred. Increased levels of the complement activation product C4d, as detected by ELISA in serum after incubation with IL-1α-stimulated cartilage, confirmed the selected reaction monitoring results indicating complement activation. Further, typical activated (cleaved) C3 fragments were detected by Western blotting in extracts of IL-1α-stimulated cartilage. No complement activation was triggered by cartilage cultured in the absence of IL-1α. Components released from IL-1α-stimulated cartilage during culture had an inhibitory effect on complement activation. These were released after a longer incubation period with IL-1α and may represent a feedback reaction to cartilage-triggered complement activation observed after a shorter incubation period.
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Affiliation(s)
- Camilla Melin Fürst
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, S-205 02 Malmö, Sweden
| | - Emma Åhrman
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, S-221 84 Lund, Sweden; and
| | - Klas Bratteby
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, S-205 02 Malmö, Sweden
| | - Sofia Waldemarson
- Department of Immunotechnology, Lund University, S-223 81 Lund, Sweden
| | - Johan Malmström
- Division of Infection Medicine, Department of Clinical Sciences Lund, Lund University, S-221 84 Lund, Sweden; and
| | - Anna M Blom
- Division of Medical Protein Chemistry, Department of Translational Medicine, Lund University, S-205 02 Malmö, Sweden;
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21
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Emerging targets in osteoarthritis therapy. Curr Opin Pharmacol 2015; 22:51-63. [PMID: 25863583 DOI: 10.1016/j.coph.2015.03.004] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 03/17/2015] [Indexed: 02/08/2023]
Abstract
Osteoarthritis (OA) is a destructive joint disease in which the initiation may be attributed to direct injury and mechanical disruption of joint tissues, but the progressive changes are dependent on active cell-mediated processes that can be observed or inferred during the generally long time-course of the disease. Based on clinical observations and experimental studies, it is now recognized a that it is possible for individual patients to exhibit common sets of symptoms and structural abnormalities due to distinct pathophysiological pathways that act independently or in combination. Recent research that has focused on the underlying mechanisms involving biochemical cross talk among the cartilage, synovium, bone, and other joint tissues within a background of poorly characterized genetic factors will be addressed in this review.
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22
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Role of Complement on Broken Surfaces After Trauma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 865:43-55. [PMID: 26306442 DOI: 10.1007/978-3-319-18603-0_3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Activation of both the complement and coagulation cascade after trauma and subsequent local and systemic inflammatory response represent a major scientific and clinical problem. After severe tissue injury and bone fracture, exposure of innate immunity to damaged cells and molecular debris is considered a main trigger of the posttraumatic danger response. However, the effects of cellular fragments (e.g., histones) on complement activation remain enigmatic. Furthermore, direct effects of "broken" bone and cartilage surfaces on the fluid phase response of complement and its interaction with key cells of connective tissues are still unknown. Here, we summarize data suggesting direct and indirect complement activation by extracellular and cellular danger associated molecular patterns. In addition, key complement components and the corresponding receptors (such as C3aR, C5aR) have been detected on "exposed surfaces" of the damaged regions. On a cellular level, multiple effects of complement activation products on osteoblasts, osteoclasts, chondrocytes and mesenchymal stem cells have been found.In conclusion, the complement system may be activated by trauma-altered surfaces and is crucially involved in connective tissue healing and posttraumatic systemic inflammatory response.
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23
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Gaudet AD, Popovich PG. Extracellular matrix regulation of inflammation in the healthy and injured spinal cord. Exp Neurol 2014; 258:24-34. [PMID: 25017885 DOI: 10.1016/j.expneurol.2013.11.020] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 11/18/2013] [Accepted: 11/19/2013] [Indexed: 02/06/2023]
Abstract
Throughout the body, the extracellular matrix (ECM) provides structure and organization to tissues and also helps regulate cell migration and intercellular communication. In the injured spinal cord (or brain), changes in the composition and structure of the ECM undoubtedly contribute to regeneration failure. Less appreciated is how the native and injured ECM influences intraspinal inflammation and, conversely, how neuroinflammation affects the synthesis and deposition of ECM after CNS injury. In all tissues, inflammation can be initiated and propagated by ECM disruption. Molecules of ECM newly liberated by injury or inflammation include hyaluronan fragments, tenascins, and sulfated proteoglycans. These act as "damage-associated molecular patterns" or "alarmins", i.e., endogenous proteins that trigger and subsequently amplify inflammation. Activated inflammatory cells, in turn, further damage the ECM by releasing degradative enzymes including matrix metalloproteinases (MMPs). After spinal cord injury (SCI), destabilization or alteration of the structural and chemical compositions of the ECM affects migration, communication, and survival of all cells - neural and non-neural - that are critical for spinal cord repair. By stabilizing ECM structure or modifying their ability to trigger the degradative effects of inflammation, it may be possible to create an environment that is more conducive to tissue repair and axon plasticity after SCI.
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Affiliation(s)
- Andrew D Gaudet
- Center for Brain and Spinal Cord Repair, Department of Neuroscience, College of Medicine, The Ohio State University, 670 Biomedical Research Tower, 460 West 12th Ave., Columbus, OH 43210, USA.
| | - Phillip G Popovich
- Center for Brain and Spinal Cord Repair, Department of Neuroscience, College of Medicine, The Ohio State University, 670 Biomedical Research Tower, 460 West 12th Ave., Columbus, OH 43210, USA.
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