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Atta G, Tempfer H, Kaser-Eichberger A, Traweger A, Heindl LM, Schroedl F. Is the human sclera a tendon-like tissue? A structural and functional comparison. Ann Anat 2021; 240:151858. [PMID: 34798297 DOI: 10.1016/j.aanat.2021.151858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 09/22/2021] [Accepted: 11/09/2021] [Indexed: 12/17/2022]
Abstract
Collagen rich connective tissues fulfill a variety of important functions throughout the human body, most of which having to resist mechanical challenges. This review aims to compare structural and functional aspects of tendons and sclera, two tissues with distinct location and function, but with striking similarities regarding their cellular content, their extracellular matrix and their low degree of vascularization. The description of these similarities meant to provide potential novel insight for both the fields of orthopedic research and ophthalmology.
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Affiliation(s)
- Ghada Atta
- Department of Ophthalmology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Institute for Tendon and Bone Regeneration, Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Herbert Tempfer
- Institute for Tendon and Bone Regeneration, Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Alexandra Kaser-Eichberger
- Center for Anatomy and Cell Biology, Institute of Anatomy and Cell Biology - Salzburg, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg, Austria
| | - Andreas Traweger
- Institute for Tendon and Bone Regeneration, Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Salzburg, Austria; Austrian Cluster for Tissue Regeneration, Vienna, Austria
| | - Ludwig M Heindl
- Department of Ophthalmology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany; Center for Integrated Oncology (CIO) Aachen - Bonn - Cologne - Düsseldorf, Cologne, Germany
| | - Falk Schroedl
- Center for Anatomy and Cell Biology, Institute of Anatomy and Cell Biology - Salzburg, Paracelsus Medical University, Strubergasse 21, 5020 Salzburg, Austria.
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2
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Ozdogan CY, Kenar H, Davun KE, Yucel D, Doger E, Alagoz S. An in vitro 3D diabetic human skin model from diabetic primary cells. Biomed Mater 2020; 16:015027. [PMID: 33331294 DOI: 10.1088/1748-605x/abc1b1] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Diabetes mellitus, a complex metabolic disorder, leads to many health complications like kidney failure, diabetic heart disease, stroke, and foot ulcers. Treatment approaches of diabetes and identification of the mechanisms underlying diabetic complications of the skin have gained importance due to continued rapid increase in the diabetes incidence. A thick and pre-vascularized in vitro 3D type 2 diabetic human skin model (DHSM) was developed in this study. The methacrylated gelatin (GelMA) hydrogel was produced by photocrosslinking and its pore size (54.85 ± 8.58 μm), compressive modulus (4.53 ± 0.67 kPa) and swelling ratio (17.5 ± 2.2%) were found to be suitable for skin tissue engineering. 8% GelMA hydrogel effectively supported the viability, spreading and proliferation of human dermal fibroblasts. By isolating dermal fibroblasts, human umbilical vein endothelial cells and keratinocytes from type 2 diabetic patients, an in vitro 3D type 2 DHSM, 12 mm in width and 1.86 mm thick, was constructed. The skin model consisted of a continuous basal epidermal layer and a dermal layer with blood capillary-like structures, ideal for evaluating the effects of anti-diabetic drugs and wound healing materials and factors. The functionality of the DHSM was showed by applying a therapeutic hydrogel into its central wound; especially fibroblast migration to the wound site was evident in 9 d. We have demonstrated that DHSM is a biologically relevant model with sensitivity and predictability in evaluating the diabetic wound healing potential of a therapeutic material.
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Affiliation(s)
- Candan Yilmaz Ozdogan
- Experimental and Clinical Research Center, Diabetes and Obesity Research Laboratory, Kocaeli University, Kocaeli, Turkey. Department of Biology, Graduate School of Natural and Applied Sciences, Kocaeli University, Kocaeli, Turkey
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Lassaigne CC, Boyer C, Sautier L, Taeymans O. Ultrasound of the normal canine supraspinatus tendon: comparison with gross anatomy and histology. Vet Rec 2019; 186:e14. [PMID: 31767697 DOI: 10.1136/vr.105552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 10/28/2019] [Accepted: 11/04/2019] [Indexed: 11/03/2022]
Abstract
BACKGROUND This study aimed to compare the ultrasonographic and histological features of the supraspinatus tendon (ST) and its peculiar appearance in contrast with the biceps brachii tendon. METHODS For this purpose, 19 non-lame dog cadavers were subjected to an ultrasonographic and histologic evaluation of both shoulders after postmortem examination. RESULTS Close to their insertion on the greater tubercle, all STs displayed a widened portion with a deep central hypoechoic area lacking a fibrillar pattern, when compared with its more proximal aspect and adjacent biceps brachii. Histologically this deep portion corresponded to poorly organised collagen bundles interspersed within a myxoid substance mainly composed of mucopolysaccharides. This central myxoid area with collagen disarray was responsible for the reduced echogenicity on ultrasound. CONCLUSION The focal widening of the ST insertion and its central mucopolysaccharidic composition could be an anatomical adaptation to marked forces specifically applied to this tendon. However, the ultrasound and histological appearances are very similar to those described in tendinosis, which represents a confounding factor in diagnosing tendonitis at the insertion of the supraspinatus. In the absence of other ultrasonographic criteria of tendinopathy, a hypoechoic central area in the ST near its insertion should be considered normal.
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Affiliation(s)
| | - Charlotte Boyer
- Biopôle, Unité d'Histologie, d'Embryologie et d'Anatomie pathologique, Ecole Nationale Veterinaire d'Alfort, Maisons-Alfort, Île-de-France, France
| | - Lucile Sautier
- Biopôle, Unité d'Histologie, d'Embryologie et d'Anatomie pathologique, Ecole Nationale Veterinaire d'Alfort, Maisons-Alfort, Île-de-France, France
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Pownder SL, Caserto BG, Hayashi K, Norman ML, Potter HG, Koff MF. Magnetic resonance imaging and histologic features of the supraspinatus tendon in nonlame dogs. Am J Vet Res 2018; 79:836-844. [DOI: 10.2460/ajvr.79.8.836] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Brennan DA, Conte AA, Kanski G, Turkula S, Hu X, Kleiner MT, Beachley V. Mechanical Considerations for Electrospun Nanofibers in Tendon and Ligament Repair. Adv Healthc Mater 2018; 7:e1701277. [PMID: 29603679 DOI: 10.1002/adhm.201701277] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/15/2018] [Indexed: 12/22/2022]
Abstract
Electrospun nanofibers possess unique qualities such as nanodiameter, high surface area to volume ratio, biomimetic architecture, and tunable chemical and electrical properties. Numerous studies have demonstrated the potential of nanofibrous architecture to direct cell morphology, migration, and more complex biological processes such as differentiation and extracellular matrix (ECM) deposition through topographical guidance cues. These advantages have created great interest in electrospun fibers for biomedical applications, including tendon and ligament repair. Electrospun nanofibers, despite their nanoscale size, generally exhibit poor mechanical properties compared to larger conventionally manufactured polymer fiber materials. This invites the question of what role electrospun polymer nanofibers can play in tendon and ligament repair applications that have both biological and mechanical requirements. At first glance, the strength and stiffness of electrospun nanofiber grafts appear to be too low to fill the rigorous loading conditions of these tissues. However, there are a number of strategies to enhance and tune the mechanical properties of electrospun nanofiber grafts. As researchers design the next-generation electrospun tendon and ligament grafts, it is critical to consider numerous physiologically relevant mechanical criteria and to evaluate graft mechanical performance in conditions and loading environments that reflect in vivo conditions and surgical fixation methods.
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Affiliation(s)
- David A. Brennan
- Department of Biomedical Engineering Rowan University 201 Mullica Hill Road, Rowan Hall Glassboro NJ 08028 USA
| | - Adriano A. Conte
- Department of Biomedical Engineering Rowan University 201 Mullica Hill Road, Rowan Hall Glassboro NJ 08028 USA
| | - Gregory Kanski
- Cooper Bone and Joint Institute and Cooper Medical School, Rowan University 3 Cooper Plaza Camden NJ 08103 USA
| | - Stefan Turkula
- Cooper Bone and Joint Institute and Cooper Medical School, Rowan University 3 Cooper Plaza Camden NJ 08103 USA
| | - Xiao Hu
- Department of Biomedical Engineering Rowan University 201 Mullica Hill Road, Rowan Hall Glassboro NJ 08028 USA
- Department of Physics and Astronomy Rowan University 201 Mullica Hill Road, Rowan Hall Glassboro NJ 08028 USA
| | - Matthew T. Kleiner
- Cooper Bone and Joint Institute and Cooper Medical School, Rowan University 3 Cooper Plaza Camden NJ 08103 USA
| | - Vince Beachley
- Department of Biomedical Engineering Rowan University 201 Mullica Hill Road, Rowan Hall Glassboro NJ 08028 USA
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Abrams GD, Luria A, Carr RA, Rhodes C, Robinson WH, Sokolove J. Association of synovial inflammation and inflammatory mediators with glenohumeral rotator cuff pathology. J Shoulder Elbow Surg 2016; 25:989-97. [PMID: 26775747 DOI: 10.1016/j.jse.2015.10.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 10/06/2015] [Accepted: 10/18/2015] [Indexed: 02/01/2023]
Abstract
HYPOTHESIS We hypothesized that patients with full-thickness rotator cuff tears would have greater synovial inflammation compared with those without rotator cuff tear pathology, with gene expression relating to histologic findings. METHODS Synovial sampling was performed in 19 patients with full-thickness rotator cuff tears (RTC group) and in 11 patients without rotator cuff pathology (control group). Cryosections were stained and examined under light microscopy and confocal fluorescent microscopy for anti-cluster CD45 (common leukocyte antigen), anti-CD31 (endothelial), and anti-CD68 (macrophage) cell surface markers. A grading system was used to quantitate synovitis under light microscopy, and digital image analysis was used to quantify the immunofluorescence staining area. Quantitative polymerase chain reaction was performed for validated inflammatory markers. Data were analyzed with analysis of covariance, Mann-Whitney U, and Spearman rank order testing, with significance set at α = .05. RESULTS The synovitis score was significantly increased in the RTC group compared with controls. Immunofluorescence demonstrated significantly increased staining for CD31, CD45, and CD68 in the RTC vs control group. CD45+/68- cells were found perivascularly, with CD45+/68+ cells toward the joint lining edge of the synovium. Levels of matrix metalloproteinase-3 (MMP-3) and interleukin-6 were significantly increased in the RTC group, with a positive correlation between the synovitis score and MMP-3 expression. CONCLUSIONS Patients with full-thickness rotator cuff tears have greater levels of synovial inflammation, angiogenesis, and MMP-3 upregulation compared with controls. Gene expression of MMP-3 correlates with the degree of synovitis.
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Affiliation(s)
- Geoffrey D Abrams
- Department of Orthopedic Surgery, Stanford University, Stanford, CA, USA; VA Palo Alto Healthcare System, Palo Alto, CA, USA.
| | - Ayala Luria
- VA Palo Alto Healthcare System, Palo Alto, CA, USA
| | | | | | - William H Robinson
- VA Palo Alto Healthcare System, Palo Alto, CA, USA; Division of Immunology/Rheumatology, Stanford University, Stanford, CA, USA
| | - Jeremy Sokolove
- VA Palo Alto Healthcare System, Palo Alto, CA, USA; Division of Immunology/Rheumatology, Stanford University, Stanford, CA, USA
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Spall BF, Fransson BA, Martinez SA, Wilkinson TE. Tendon Volume Determination on Magnetic Resonance Imaging of Supraspinatus Tendinopathy. Vet Surg 2016; 45:386-91. [PMID: 26909657 DOI: 10.1111/vsu.12452] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
OBJECTIVE To determine the supraspinatus tendon volume using magnetic resonance imaging (MRI) in dogs with non-calcified supraspinatus tendinopathy (NCST), in dogs with orthopedic disease other than NCST, and in healthy dogs. STUDY DESIGN Case series. ANIMALS Twenty-two dogs (18 client-owned dogs; 4 purpose-bred dogs). METHODS Dogs undergoing shoulder MRI were categorized as NCST if they were diagnosed with NCST only, had histologic confirmed diagnosis, underwent surgical treatment, and were available for follow-up longer than 4 months. Dogs with MRI performed for a forelimb lameness because of a diagnosis other than NCST were categorized as orthopedic control (OC). Healthy dogs from an unrelated study were categorized as healthy controls (HC). Tendon volume was determined from MRI using public domain software and compared across categories. RESULTS The study included 9 NCST dogs, 9 OC dogs, and 4 HC dogs. The median tendon volume for NCST was 1,323 mm(3), OC was 630 mm(3), and HC was 512 mm(3). The volume was significantly higher in the NCST than OC (P = .0012) and HC (P = .003). There was no difference between OC and HC (P = .76). CONCLUSION Dogs diagnosed with NCST had higher supraspinatus tendon volumes compared to dogs with other orthopedic disorders and healthy dogs.
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Lamplot JD, Angeline M, Angeles J, Beederman M, Wagner E, Rastegar F, Scott B, Skjong C, Mass D, Kang R, Ho S, Shi LL. Distinct effects of platelet-rich plasma and BMP13 on rotator cuff tendon injury healing in a rat model. Am J Sports Med 2014; 42:2877-87. [PMID: 25193888 DOI: 10.1177/0363546514547171] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Although platelet-rich plasma (PRP) is used clinically to augment tendon healing, bone morphogenetic protein-13 (BMP13) may provide a better therapeutic avenue to improve early tendon healing and repair. HYPOTHESIS Exogenous expression of BMP13 in tenocytes will up-regulate genes involved in tendon healing. Direct delivery of adenovirus-mediated BMP13 (AdBMP13) into the injured rat supraspinatus tendon will increase biomechanical properties. STUDY DESIGN Controlled laboratory study. METHODS Exogenous expression of BMP13 and the major growth factors in PRP (transforming growth factor-β1 [TGF-β1], vascular endothelial growth factor-A [VEGF-A], and platelet-derived growth factor-BB [PDGF-BB]) was accomplished by using recombinant adenoviral vectors. The expression of tendon- and matrix-associated genes in growth factor-treated tenocytes was analyzed by use of semiquantitative reverse-transcription polymerase chain reaction. A total of 32 rats with supraspinatus defect were divided into 4 groups and injected with adenovirus-containing green fluorescent protein (AdGFP; negative control), PRP, AdBMP13, or PRP+AdBMP13. All rats were sacrificed at 2 weeks after surgery, and tendons were harvested for biomechanical testing and histologic analysis. RESULTS BMP13 up-regulated type III collagen expression compared with AdGFP control and PRP growth factors (P < .01). BMP13 and PRP growth factors each up-regulated fibronectin expression (P < .01). There was an increase in stress to failure in each of the 3 treatment groups (P < .05 for PRP; P < .01 for AdBMP13 or PRP+AdBMP13) compared with AdGFP control. AdBMP13 demonstrated higher stress to failure than did the PRPs (P < .01). The addition of PRP did not increase the BMP13-enhanced stress to failure or stiffness. The biomechanical results were further supported by histologic analysis of the retrieved samples. CONCLUSION Exogenous expression of BMP13 enhances tendon healing more effectively than PRP as assessed by tendon- and matrix-associated gene expression, biomechanical testing, and histologic analysis. CLINICAL RELEVANCE While PRP is used in the clinical setting, BMP13 may be explored as a superior biofactor to improve rotator cuff tendon healing and reduce the incidence of retears.
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Affiliation(s)
- Joseph D Lamplot
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Michael Angeline
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Jovito Angeles
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Maureen Beederman
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Eric Wagner
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Farbod Rastegar
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Bryan Scott
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Christian Skjong
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Daniel Mass
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Richard Kang
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Sherwin Ho
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
| | - Lewis L Shi
- Department of Orthopaedic Surgery and Rehabilitation Medicine, The University of Chicago Medical Center, Chicago, Illinois, USA
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Cheng CW, Solorio LD, Alsberg E. Decellularized tissue and cell-derived extracellular matrices as scaffolds for orthopaedic tissue engineering. Biotechnol Adv 2014; 32:462-84. [PMID: 24417915 PMCID: PMC3959761 DOI: 10.1016/j.biotechadv.2013.12.012] [Citation(s) in RCA: 241] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 12/27/2013] [Accepted: 12/31/2013] [Indexed: 02/07/2023]
Abstract
The reconstruction of musculoskeletal defects is a constant challenge for orthopaedic surgeons. Musculoskeletal injuries such as fractures, chondral lesions, infections and tumor debulking can often lead to large tissue voids requiring reconstruction with tissue grafts. Autografts are currently the gold standard in orthopaedic tissue reconstruction; however, there is a limit to the amount of tissue that can be harvested before compromising the donor site. Tissue engineering strategies using allogeneic or xenogeneic decellularized bone, cartilage, skeletal muscle, tendon and ligament have emerged as promising potential alternative treatment. The extracellular matrix provides a natural scaffold for cell attachment, proliferation and differentiation. Decellularization of in vitro cell-derived matrices can also enable the generation of autologous constructs from tissue specific cells or progenitor cells. Although decellularized bone tissue is widely used clinically in orthopaedic applications, the exciting potential of decellularized cartilage, skeletal muscle, tendon and ligament cell-derived matrices has only recently begun to be explored for ultimate translation to the orthopaedic clinic.
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Affiliation(s)
- Christina W Cheng
- Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Wickenden Building, Rm 218, Cleveland, OH, USA; Department of Orthopaedic Surgery, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH, USA.
| | - Loran D Solorio
- Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Wickenden Building, Rm 218, Cleveland, OH, USA.
| | - Eben Alsberg
- Department of Biomedical Engineering, Case Western Reserve University, 10900 Euclid Avenue, Wickenden Building, Rm 218, Cleveland, OH, USA; Department of Orthopaedic Surgery, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH, USA; National Center for Regenerative Medicine, Division of General Medical Sciences, Case Western Reserve University, Cleveland, OH, USA.
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10
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Abstract
Matrix metalloproteinases (MMP) are involved in the development of tendinopathy. These potent enzymes completely degrade all components of the connective tissue, modify the extracellular matrix (ECM), and mediate the development of painful tendinopathy. To control the local activity of activated proteinases, the same cells produce tissue inhibitors of metalloproteinases (TIMP). These latter bind to the enzyme and prevent degradation. The balance between the activities of MMPs and TIMPs regulates tendon remodeling, whereas an imbalance produces a collagen dis-regulation and disturbances in tendons. ADAMs (a disintegrin and metalloproteinase) are cell membrane-linked enzymes with proteolytic and cell signaling functions. ADAMTSs (ADAM with thrombospondin motifs) are secreted into the circulation and constitute a heterogenous family of proteases with both anabolic and catabolic functions. Further studies are needed to better define the mechanism of action, and whether these new strategies are safe and effective in larger models.
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Affiliation(s)
- Angelo Del Buono
- Department of Orthopaedic and Trauma Surgery, Campus Biomedico University of Rome, Italy
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Del Buono A, Oliva F, Longo UG, Rodeo SA, Orchard J, Denaro V, Maffulli N. Metalloproteases and rotator cuff disease. J Shoulder Elbow Surg 2012; 21:200-8. [PMID: 22244063 DOI: 10.1016/j.jse.2011.10.020] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 10/22/2011] [Accepted: 10/24/2011] [Indexed: 02/07/2023]
Abstract
The molecular changes occurring in rotator cuff tears are still unknown, but much attention has been paid to better understand the role of matrix metalloproteinases (MMP) in the development of tendinopathy. These are potent enzymes that, once activated, can completely degrade all components of the connective tissue, modify the extracellular matrix (ECM), and mediatethe development of painful tendinopathy and tendon rupture. To control the local activity of activated proteinases, the same cells produce tissue inhibitors of metalloproteinases (TIMP) that bind to the enzymes and prevent degradation. The balance between the activities of MMPs and TIMPs regulates tendon remodeling, whereas an imbalance produces a collagen dis-regulation and disturbances intendons. ADAMs (a disintegrin and metalloproteinase) are cell membrane-linked enzymes with proteolytic and cell signaling functions. ADAMTSs (ADAM with thrombospondin motifs) are secreted into the circulation, and constitute a heterogenous family of proteases with both anabolic and catabolic functions. Biologic modulation of endogenous MMP activity to basal levels may reduce pathologic tissue degradation and favorably influence healing after rotator cuff repair. Further studies are needed to better define the mechanism of action, and whether these new strategies are safe and effective in larger models.
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Affiliation(s)
- Angelo Del Buono
- Department of Orthopaedic and Trauma Surgery, Campus Biomedico, University of Rome, Rome, Italy
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12
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Shirachi I, Gotoh M, Mitsui Y, Yamada T, Nakama K, Kojima K, Okawa T, Higuchi F, Nagata K. Collagen production at the edge of ruptured rotator cuff tendon is correlated with postoperative cuff integrity. Arthroscopy 2011; 27:1173-9. [PMID: 21752571 DOI: 10.1016/j.arthro.2011.03.078] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 03/13/2011] [Accepted: 03/16/2011] [Indexed: 02/02/2023]
Abstract
PURPOSE The purpose was to evaluate the correlation between messenger RNA (mRNA) expression of collagen at the edge of the ruptured rotator cuff tendon and postoperative cuff integrity. METHODS The edge of the ruptured tendon was sampled during open rotator cuff surgery in 12 patients with full-thickness rotator cuff tears (mean age, 58.2 years). The mean period from symptom onset was 9.3 months (range, 1 to 36 months), and the mean tear size was 4.1 cm. As controls, rotator cuff tendons with no gross rupture were taken from 5 fresh cadavers. Production of type I and type III collagen was examined by real-time reverse transcription polymerase chain reaction. By use of magnetic resonance imaging, postoperative cuff integrity was evaluated based on the classification of Sugaya et al. and then scored, ranging from 5 points for type I to 1 point for type V. RESULTS Looking at the mRNA of type I and type III collagen in tendons, we found that the expression of mRNA for both collagen types in ruptured tendons was significantly greater than in control tendons (P = .0462 for type I collagen and P = .0306 for type III collagen). Correlating the mRNA of type I and type III collagen with repaired cuff integrity on postoperative magnetic resonance imaging, we found a close relation between expression of mRNA for both collagen types and postoperative rotator cuff integrity (r = 0.63 [P = .038] for type I collagen and r = 0.626 [P = .03] for type III collagen). Furthermore, expression of type I collagen mRNA showed a significant inverse correlation with the period from symptom onset (r = -0.845, P < .0005). CONCLUSIONS This study showed that expression of mRNA for type I and type III collagen at the edge of the ruptured rotator cuff tendon was significantly correlated with postoperative cuff integrity and that mRNA expression for type I collagen was significantly associated with the period from symptom onset. These results may suggest that conservative treatment should not be prolonged if patients do not respond within a certain period. LEVEL OF EVIDENCE Level III, prognostic case-control study.
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Affiliation(s)
- Isao Shirachi
- Department of Orthopedic Surgery, Kurume University, Kurume, Japan
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Chaudhury S, Dicko C, Burgess M, Vollrath F, Carr AJ. Fourier transform infrared spectroscopic analysis of normal and torn rotator-cuff tendons. ACTA ACUST UNITED AC 2011; 93:370-7. [DOI: 10.1302/0301-620x.93b3.25470] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We have used Fourier transform infrared spectroscopy (FTIR) to characterise the chemical and structural composition of the tendons of the rotator cuff and to identify structural differences among anatomically distinct tears. Such information may help to identify biomarkers of tears and to provide insight into the rates of healing of different sizes of tear. The infrared spectra of 81 partial, small, medium, large and massive tears were measured using FTIR and compared with 11 uninjured control tendons. All the spectra were classified using standard techniques of multivariate analysis. FTIR readily differentiates between normal and torn tendons, and different sizes of tear. We identified the key discriminating molecules and spectra altered in torn tendons to be carbohydrates/phospholipids (1030 cm−1 to 1200 cm−1), collagen (1300 cm−1 to 1700 cm−1 and 3000 cm−1 to 3350 cm−1) and lipids (2800 cm−1 to 3000 cm−1). Our study has shown that FTIR spectroscopy can identify tears of the rotator cuff of varying size based upon distinguishable chemical and structural features. The onset of a tear is mainly associated with altered structural arrangements of collagen, with changes in lipids and carbohydrates. The approach described is rapid and has the potential to be used peri-operatively to determine the quality of the tendon and the extent of the disease, thus guiding surgical repair.
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Affiliation(s)
- S. Chaudhury
- Department of Orthopaedics, Nuffield Orthopaedic Centre, University of Oxford, Oxford OX3 7LD, UK
| | - C. Dicko
- Department of Zoology University of Oxford, Oxford OX1 3PS, UK
| | - M. Burgess
- Department of Orthopaedics, Nuffield Orthopaedic Centre, University of Oxford, Oxford OX3 7LD, UK
| | - F. Vollrath
- Department of Zoology University of Oxford, Oxford OX1 3PS, UK
| | - A. J. Carr
- Department of Orthopaedics, Nuffield Orthopaedic Centre, University of Oxford, Oxford OX3 7LD, UK
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Klinger HM, Koelling S, Baums MH, Kahl E, Steckel H, Smith MM, Schultz W, Miosge N. Cell biological and biomechanical evaluation of two different fixation techniques for rotator cuff repair. Scand J Med Sci Sports 2009; 19:329-37. [PMID: 18397194 DOI: 10.1111/j.1600-0838.2008.00791.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Our objective was to evaluate the cell biology and biomechanical aspects of the healing process after two different techniques in open rotator cuff surgery - double-loaded bio-absorbable suture anchors combined with so-called arthroscopic Mason-Allen stitches (AAMA) and a trans-osseous suture technique combined with traditional modified Mason-Allen stitches (SMMA). Thirty-six mature sheep were randomized into two repair groups. After 6, 12, or 26 weeks, evaluation of the reinsertion site of the infraspinatus tendon was performed. The mechanical load-to-failure and stiffness results did not indicate a significant difference between the two groups. After 26 weeks, fibrocartilage was sparse in the AAMA group, whereas the SMMA group showed the most pronounced amount of fibrocartilage. We found no ultrastructural differences in collagen fiber organization between the two groups. The relative expression of collagen type II mRNA in the normal group was 1.11. For the AAMA group, 6 weeks after surgery, the relative expression was 55.47, whereas for the SMMA group it was 1.90. This in vivo study showed that the AAMA group exhibited a tendon-to-bone healing process more favorable in its cell biology than that of the traditional SMMA technique. Therefore, the AAMA technique might also be more appropriate for arthroscopic repair.
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Affiliation(s)
- H-M Klinger
- Department of Orthopedic Surgery, Georg-August-University, Goettingen, Germany.
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15
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Ganesan K, Tiwari M, Balachandran C, Manohar BM, Puvanakrishnan R. Estrogen and testosterone attenuate extracellular matrix loss in collagen-induced arthritis in rats. Calcif Tissue Int 2008; 83:354-64. [PMID: 18931819 DOI: 10.1007/s00223-008-9183-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Accepted: 09/11/2008] [Indexed: 10/21/2022]
Abstract
Rheumatoid arthritis (RA) is a sexually dimorphic, autoimmune inflammatory disorder affecting the joints. Joint disability in RA results primarily from loss of matrix components (collagen and glycosoaminoglycan) in the cartilage and synovium. This study was carried out to understand the effect of physiological levels of testosterone, estrogen, and progesterone on oxidative stress-induced changes in matrix composition in rat synovium in arthritis. Arthritis induction in castrated and ovariectomized rats resulted in enhanced oxidative stress and this was assessed by lipid peroxidation levels and depletion of antioxidants. This, in turn, led to significantly (p < 0.01) increased levels of TNF-alpha and matrix metalloproteinase-2 (MMP-2), subsequently resulting in loss of collagen, elastin, and glycosoaminoglycan (GAG) and disorganization of reticulin as evidenced by biochemical quantitation and also by staining for collagen, reticulin, and elastin. Treatment with physiological doses of dihydrotestosterone (25 mg topically) and estrogen (5 microg/0.1 ml subcutaneously) restored the antioxidant levels significantly (p < 0.05) and reduced the levels of TNF-alpha and MMP-2, with estrogen exhibiting a higher potency. This, in turn, attenuated the damage to reticulin organization as well as the loss of collagen and GAG in the articular tissues. However, elastin loss could not be attenuated by either treatment. Progesterone (2 mg/0.1 ml subcutaneously) was not shown to have any significance in disease modification, and on the contrary, it inhibited the protective effects of estrogen. However, progesterone contributed to increased collagen levels in the tissues.
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Affiliation(s)
- Kalaivani Ganesan
- Department of Biotechnology, Central Leather Research Institute, Adyar, Chennai, 600 020, India
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16
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Abstract
Twenty-five years ago, the Journal of Orthopaedic Research published its first volume, which included five articles covering topics in tendon and ligament research. Since then, the body of tendon and ligament research has continued to increase exponentially. This review summarizes major advancements in tendon and ligament research since the initial publication of this journal. The purpose of this article is not to provide an in-depth review of all of tendon and ligament research, but instead to provide a concise literature review of some of the major and recurring areas of research. The general topics covered over the last 25 years include tissue properties, tendinopathy, healing, and engineered scaffolds.
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Affiliation(s)
- LeAnn M Dourte
- McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 36th Street and Hamilton Walk, Philadelphia, Pennsylvania 19104-6081, USA
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17
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Cen L, Liu W, Cui L, Zhang W, Cao Y. Collagen tissue engineering: development of novel biomaterials and applications. Pediatr Res 2008; 63:492-6. [PMID: 18427293 DOI: 10.1203/pdr.0b013e31816c5bc3] [Citation(s) in RCA: 417] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Scientific investigations involving collagen have inspired tissue engineering and design of biomaterials since collagen fibrils and their networks primarily regulate and define most tissues. The collagen networks form a highly organized, three-dimensional architecture to entrap other ingredients. Biomaterials are expected to function as cell scaffolds to replace native collagen-based extracellular matrix. The composition and properties of biomaterials used as scaffold for tissue engineering significantly affect the regeneration of neo-tissues and influence the conditions of collagen engineering. The complex scenario of collagen characteristics, types, fibril arrangement, and collagen structure-related functions (in a variety of connective tissues including bone, cartilage, tendon, skin and cornea) are addressed in this review. Discussion will focus on nanofibrillar assemblies and artificial synthetic peptides that mimic either the fibrillar structure or the elemental components of type I collagen as illustrated by their preliminary applications in tissue engineering. Conventional biomaterials used as scaffolds in engineering collagen-containing tissues are also discussed. The design of novel biomaterials and application of conventional biomaterials will facilitate development of additional novel tissue engineering bioproducts by refining the currently available techniques. The field of tissue engineering will ultimately be advanced by increasing control of collagen in native tissue and by continual manipulation of biomaterials.
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Affiliation(s)
- Lian Cen
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
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18
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Johns DE, Athanasiou KA. Design characteristics for temporomandibular joint disc tissue engineering: learning from tendon and articular cartilage. Proc Inst Mech Eng H 2007; 221:509-26. [PMID: 17822153 DOI: 10.1243/09544119jeim158] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Tissue engineering of chondrocytic or fibroblastic musculoskeletal tissues has been relatively well studied compared with that of the temporomandibular joint (TMJ) disc. Early attempts at tissue engineering the disc have been misguided owing to a lack of understanding of the composition and function of the TMJ disc. The objective of this review is to compare the TMJ disc with a chondrocytic tissue (hyaline articular cartilage) and a fibroblastic tissue (tendon) to understand better the properties of this fibrocartilaginous tissue. The TMJ disc has 25 times more glycosaminoglycan (GAG) per dry weight than tendon but half that of articular cartilage. The disc's tensile modulus is six times more than cartilage but orders less than tendon. The GAG content and tensile modulus suggest that the TMJ disc is characterized as a tissue between hyaline cartilage and tendon, but the disc appears more tendon like when considering its collagen make-up and cell content. Like tendon, the TMJ disc contains primarily collagen type I at 85 per cent per dry weight, while articular cartilage has 30 per cent less collagen, which is type II. Knowledge of quantitative comparisons between joint tissues can give extensive insight into how to improve tissue engineering of the TMJ disc.
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Affiliation(s)
- D E Johns
- Department of Bioengineering, Rice University, Houston, Texas 77251, USA
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19
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Abstract
Tendons are able to respond to mechanical forces by altering their structure, composition, and mechanical properties--a process called tissue mechanical adaptation. The fact that mechanical adaptation is effected by cells in tendons is clearly understood; however, how cells sense mechanical forces and convert them into biochemical signals that ultimately lead to tendon adaptive physiological or pathological changes is not well understood. Mechanobiology is an interdisciplinary study that can enhance our understanding of mechanotransduction mechanisms at the tissue, cellular, and molecular levels. The purpose of this article is to provide an overview of tendon mechanobiology. The discussion begins with the mechanical forces acting on tendons in vivo, tendon structure and composition, and its mechanical properties. Then the tendon's response to exercise, disuse, and overuse are presented, followed by a discussion of tendon healing and the role of mechanical loading and fibroblast contraction in tissue healing. Next, mechanobiological responses of tendon fibroblasts to repetitive mechanical loading conditions are presented, and major cellular mechanotransduction mechanisms are briefly reviewed. Finally, future research directions in tendon mechanobiology research are discussed.
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Affiliation(s)
- James H-C Wang
- MechanoBiology Laboratory, Department of Orthopaedic Surgery, University of Pittsburgh, 210 Lothrop St., BST, E1647, Pittsburgh, PA 15213, USA.
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20
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Lo IKY, Boorman R, Marchuk L, Hollinshead R, Hart DA, Frank CB. Matrix molecule mRNA levels in the bursa and rotator cuff of patients with full-thickness rotator cuff tears. Arthroscopy 2005; 21:645-51. [PMID: 15944617 DOI: 10.1016/j.arthro.2005.03.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE The purpose of this study was to evaluate at the mRNA level a subset of extracellular matrix molecules relevant during healing and remodeling of rotator cuff tears. TYPE OF STUDY Controlled laboratory study. METHODS Bursal and rotator cuff tissue from the margin of the rotator cuff tear were harvested from 10 patients (mean age, 57.5 +/- 7.3 years) undergoing surgical repair of full-thickness rotator cuff tears. There were six male and four female patients with a mean duration of symptoms of 14.6 months (range, 2 to 60 months). The mean tear size was 4.4 cm. In addition, tissue was obtained from 6 cadaveric specimens with no gross evidence of rotator cuff tearing. Reverse transcription polymerase chain reaction (RT-PCR) was performed for type I, II, and III collagen, biglycan, decorin, and aggrecan, and normalized to the housekeeping gene GAPDH. RESULTS RT-PCR showed that both the bursa and rotator cuff margin had increased mRNA levels for type I and type III collagen in patients with full-thickness rotator cuff tears when compared with normal cadaveric controls. In addition, there was a significant decrease in decorin mRNA levels and an increase in aggrecan mRNA levels in the rotator cuff margin of torn rotator cuff tendons when compared with normal cadaveric controls. CONCLUSIONS These results suggest that both the bursa and rotator cuff margin of patients with rotator cuff tears are actively remodeling after injury and that both tissues may potentially contribute to the healing process following repair. CLINICAL RELEVANCE These findings may help clinicians determine what aspects of the repair process can be manipulated to affect optimal ruptured tendon repair.
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Affiliation(s)
- Ian K Y Lo
- McCaig Centre for Joint Injury and Arthritis Research, University of Calgary, Calgary, Alberta, Canada.
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21
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Abstract
Disorganized, haphazard ineffective healing is a constant feature of chronic tendinopathy. Normal tendon is composed mostly of type I collagen. Tendinopathic tendons, conversely, have a greater proportion of type III collagen, which is associated with tendon rupture. Matrix metalloproteinases (MMPs) are involved in remodelling of the extracellular matrix (ECM) of tendons, because they are either up- or down-regulated in tendinopathy. A balance between MMPs and tissue inhibitors of metalloproteinases is required to maintain tendon homeostasis. The mechanism of activation of MMPs is poorly understood, and their precise role in tendinopathy is unclear.
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Affiliation(s)
- Merzesh Magra
- Department of Trauma and Orthopaedic Surgery, Keele University School of Medicine, Thornburrow Drive, Hartshill, Stoke-on-Trent, ST4 7QB Staffordshire, UK
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22
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Lo IKY, Marchuk LL, Hollinshead R, Hart DA, Frank CB. Matrix metalloproteinase and tissue inhibitor of matrix metalloproteinase mRNA levels are specifically altered in torn rotator cuff tendons. Am J Sports Med 2004; 32:1223-9. [PMID: 15262646 DOI: 10.1177/0363546503262200] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Rotator cuff tears are a cause of pain and disability in the shoulder. The molecular changes associated with rotator cuff tearing are unclear. A subset of matrix metalloproteinases and tissue inhibitors of metalloproteinase, which are involved in extracellular matrix remodeling and degradation, were evaluated. HYPOTHESIS There would be an increase in the mRNA level of specific matrix metalloproteinase and a decrease in the mRNA level of specific tissue inhibitors of metalloproteinase in rotator cuff tendon tissue obtained from patients with rotator cuff tears. STUDY DESIGN Controlled laboratory study. METHODS Tissue was obtained from 10 patients undergoing rotator cuff repair for full-thickness rotator cuff tears. Also, tissue was obtained from cadaveric specimens with no gross evidence of rotator cuff tearing. Reverse transcription polymerase chain reaction was performed for the collagenases (MMP-1, MMP-8, MMP-13), the stromelysins (MMP-3, MMP-10, MMP-11), and the tissue inhibitors of metalloproteinase (TIMP-1, TIMP-2, TIMP-3, TIMP-4). Western blotting was performed to confirm the mRNA changes demonstrated in collagenase-3 (MMP-13). RESULTS There was a significant increase in collagenase-3 (MMP-13) mRNA levels, a decrease in stromelysin-1 (MMP-3) mRNA levels, and a decrease in tissue inhibitor of metalloproteinase-2, -3, and -4 mRNA levels. Western blotting demonstrated an increase in the active form of collagenase-3 (MMP-13) in rotator cuff tendon tears. CONCLUSIONS The mRNA levels of specific matrix metalloproteinases and tissue inhibitors of metalloproteinase are altered in torn rotator cuff tendons. CLINICAL RELEVANCE With the known action of the matrix metalloproteinases and tissue inhibitors of metalloproteinase in extra-cellular matrix remodeling, these findings suggest that their roles in remodeling of rotator cuff tears should be further investigated.
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23
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Affiliation(s)
- G Riley
- Rheumatology Research Unit, Addenbrooke's Hospital, Cambridge CB2 2NH, UK
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24
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Takahashi S, Nakajima M, Kobayashi M, Wakabayashi I, Miyakoshi N, Minagawa H, Itoi E. Effect of recombinant basic fibroblast growth factor (bFGF) on fibroblast-like cells from human rotator cuff tendon. TOHOKU J EXP MED 2002; 198:207-14. [PMID: 12630552 DOI: 10.1620/tjem.198.207] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Rotator cuff tendon cells (RCC) derived from surgical samples showed fibroblast-like morphology. Histological staining demonstrated collagen secretion by RCC. Immunohistological findings revealed that RCC secreted type I and III collagen, but not type II collagen. In addition, the SDS-PAGE analysis suggested that RCC predominantly produced type I collagen. Basic fibroblast growth factor (bFGF) had a stimulatory effect on the proliferation of RCC dose-dependently up to 1 ng/ml. Administration of bFGF suppressed the secretion of collagens from RCC in a dose-dependent manner.
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Affiliation(s)
- Shu Takahashi
- Department of Orthopedic Surgery, Akita University School of Medicine, Akita 010-8543, Japan.
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25
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Riechert K, Labs K, Lindenhayn K, Sinha P. Semiquantitative analysis of types I and III collagen from tendons and ligaments in a rabbit model. J Orthop Sci 2001; 6:68-74. [PMID: 11289589 DOI: 10.1007/s007760170027] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The present study presents a simple and reliable micro-method for the semiquantitative analysis of types I and III collagen in tendons and ligaments in a rabbit model. After pretreatment of the analytical material by homogenization, a double cyanogen bromide cleavage was performed and the peptide fragments were visualized by polyacrylamide gel electrophoresis and silvcr staining. On the basis of this procedure, the method presented here can be used to analyze very small amounts of sample material (less than 10microg) by electrophoresis. The results of the study showed that type I collagen is predominant in the ligaments and the tendons of the knee, e.g., medial and lateral collateral ligaments. anterior and posterior cruciate ligaments. patellar tendon, achilles tendon, and semitendinosus tendon. However, a markedly higher proportion of type III collagen was detected in the ligaments (approximately 10%) than in the tendons (approximately 5%). The ligaments differ markedly from the tendons in biochemical mapping; the ligaments are functionally and metabolically the more active tissue and have a higher adaptation potential.
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Affiliation(s)
- K Riechert
- Department of Orthopaedics, Humboldt-University Charité, Berlin, Germany
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