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Anna Osiecka-Iwan, Stanislaw Moskalewski, Anna Hyc
INTRODUCTION: We have previously observed that rat synovial membranes incubated in medium containing cartilage interstitial fluid (CIF) responded by changes in the expression of hyaluronan synthases (HAS1 and HAS2), collagen type I, versican, aggrecan, lubricin, matrix metalloproteinases 2 and 3 (MMP2 and MMP3), tissue inhibitors of metalloproteinases (TIMP1, 2 and 3), transforming growth factor β1 (TGFβ1), tumor necrosis factor (TNF), interleukin (IL) 1β and IL-6. The aim of the study was to evaluate the influence of particular cytokines found in CIF on the gene expression of extracellular matrix (ECM) proteins in synovial membrane cells...
2016: Folia Histochemica et Cytobiologica
R Leonardi, R-E Perrotta, L-E Almeida, C Loreto, G Musumeci
To understand the molecular basis of temporomandibular joint (TMJ) pathologies, we aimed to investigate the lubricin levels in the TMJ synovial fluid (SF) of patients with mild to severe internal derangements (IDs)._Material and Methods: A total, 34 joints were the study group. Only patients, with a Wilkes stage of III, IV and V were included, in this sample. Control group consisted of SF from eight joints, from patients undergoing to orthognatic surgery. Concentrations of lubricin in the SF from both samples were measured using ELISA system...
October 1, 2016: Medicina Oral, Patología Oral y Cirugía Bucal
Kazumasa Miyatake, Kenjiro Iwasa, Sean M McNary, Gordon Peng, A Hari Reddi
OBJECTIVE: Superficial zone protein (SZP)/lubricin/PRG4 functions as a boundary lubricant in articular cartilage to decrease friction and wear. As articular cartilage lubrication is critical for normal joint function, the accumulation of SZP at the surface of cartilage is important for joint homeostasis. Recently, a heterocyclic compound called kartogenin (KGN) was found to induce chondrogenic differentiation and enhance mRNA expression of lubricin. The objective of this study was to determine whether KGN can stimulate synthesis of SZP in superficial zone, articular chondrocytes...
October 2016: Cartilage
Kathryn A Solka, Ira J Miller, Thomas M Schmid
Lubricin is a secreted, mucin-like glycoprotein and proteoglycan abundant in synovial fluid that provides boundary lubrication and prevents cell adhesion in synovial joints. The antilubricin S6.79 monoclonal antibody recognizes an O-linked glycopeptide epitope in lubricin's mucin domain. The central, long mucin domain of lubricin is extensively O-glycosylated with Gal(β1-3)GalNAc-O-Ser/Thr, and about two thirds of the O-glycosylated sites are capped with sialic acid. Our aim was to determine whether removal of sialic acid by sialidase could improve the detection of lubricin in a number of human tissues using the S6...
September 28, 2016: Journal of Histochemistry and Cytochemistry: Official Journal of the Histochemistry Society
Sara Edsfeldt, Björn Holm, Margit Mahlapuu, Carol Reno, David A Hart, Monica Wiig
PURPOSE: To investigate the anti-adhesive mechanisms of PXL01 in sodium hyaluronate (HA) by using the rabbit lactoferrin peptide, rabPXL01 in HA, in a rabbit model of healing tendons and tendon sheaths. The mechanism of action for PXL01 in HA is interesting since a recent clinical study of the human lactoferrin peptide PXL01 in HA administered around repaired tendons in the hand showed improved digit mobility. MATERIALS AND METHODS: On days 1, 3, and 6 after tendon injury and surgical repair, reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) was used to assess mRNA expression levels for genes encoding the mucinous glycoprotein PRG4 (also called lubricin) and a subset of matrix proteins, cytokines, and growth factors involved in flexor tendon repair...
September 23, 2016: Upsala Journal of Medical Sciences
Alessandro Lambiase, Benjamin D Sullivan, Tannin A Schmidt, David A Sullivan, Gregory Jay, Edward R Truitt, Alice Bruscolini, Marta Sacchetti, Flavio Mantelli
PURPOSE: The objective of this clinical trial (NCT02507934) was to assess the efficacy and safety of recombinant human lubricin as compared to a 0.18% sodium hyaluronate (HA) eye drop in subjects with moderate dry eye disease (DED). METHODS: DEWS Grade 2-3 subjects were randomized to use lubricin (N=19, 51.9±11.8 years) or HA (N=20, 61.8±13.3 years). After a saline washout period, subjects administered BID therapy for 7 days, followed by instillation as needed (2-6 drops per eye) for 7 days...
September 7, 2016: Ocular Surface
Erin Teeple, Naga Padmini Karamchedu, Katherine M Larson, Ling Zhang, Gary J Badger, Braden C Fleming, Gregory D Jay
The purpose of this study was to determine the effects of arthroscopic irrigation on cartilage superficial zone lubricin and surface friction. Arthroscopic partial meniscectomy is one of the most commonly performed orthopedic surgeries in the United States, but rates of osteoarthritis progression following this procedure are high. The effect of arthroscopic irrigation on articular surface lubrication has not been previously considered as a contributing factor in outcomes after arthroscopy. Fourteen bovine stifle joints were randomized to receive arthroscopic irrigation (n=7) or no treatment (n=7)...
September 6, 2016: Journal of Biomechanics
H L Reesink, A E Watts, H O Mohammed, G D Jay, A J Nixon
OBJECTIVE: The goals of this study were (1) to quantify proteoglycan 4 (PRG4) gene expression; (2) to assess lubricin immunostaining; and (3) to measure synovial fluid lubricin concentrations in clinical and experimental models of equine carpal osteoarthritis (OA). DESIGN: Lubricin synovial fluid concentrations and cartilage and synovial membrane PRG4 expression were analyzed in research horses undergoing experimental OA induction (n = 8) and in equine clinical patients with carpal OA (n = 58)...
August 4, 2016: Osteoarthritis and Cartilage
L Martin-Alarcon, T A Schmidt
The rheological properties of synovial fluid (SF) are largely attributed to the presence of high molecular weight hyaluronan (HA). However, rheological differences between SF and pure HA solutions suggest that SF proteins actively contribute towards the bulk viscoelasticity of this biological fluid. Due to various experimental challenges involved with the rheometry of low-viscosity biological fluids, the macromolecular interactions in SF and their relative rheological importance are still a matter of active discussion...
July 29, 2016: Biorheology
Hiroyasu Ogawa, Kazu Matsumoto, Nobuo Terabayashi, Kenji Kawashima, Kentaro Takeuchi, Haruhiko Akiyama
OBJECTIVES: Although lubricin plays a role in controlling inflammation and pain as well as being a mechanical lubricant, clinical relevance of lubricin concentration in synovial fluid (SF) is unknown. The purpose was to determine whether lubricin concentration in SF is associated with the clinical status of the knee. METHODS: SF was obtained from 61 knee joints from patients who underwent any knee surgery with several stages of knee osteoarthritis. Lubricin/PRG4 concentration in SF was measured by enzyme-linked immunosorbent assay (ELISA)...
July 20, 2016: Modern Rheumatology
Amjad Askary, Joanna Smeeton, Sandeep Paul, Simone Schindler, Ingo Braasch, Nicholas A Ellis, John Postlethwait, Craig T Miller, J Gage Crump
Synovial joints are the lubricated connections between the bones of our body that are commonly affected in arthritis. It is assumed that synovial joints first evolved as vertebrates came to land, with ray-finned fishes lacking lubricated joints. Here, we examine the expression and function of a critical lubricating protein of mammalian synovial joints, Prg4/Lubricin, in diverse ray-finned fishes. We find that Prg4 homologs are specifically enriched at the jaw and pectoral fin joints of zebrafish, stickleback, and gar, with genetic deletion of the zebrafish prg4b gene resulting in the same age-related degeneration of joints as seen in lubricin-deficient mice and humans...
2016: ELife
Anna Hyc, Stanislaw Moskalewski, Anna Osiecka-Iwan
Articular cartilage and the synovial membrane both ensure the smooth action of synovial joints; however, the influence of chondrocytes on synovial metabolism remains unclear. The secretory activity of chondrocytes is usually studied in cell cultures and may differ from that in intact cartilage. According to McCutchen's theory of 'weeping' joint lubrication, loading of the articular cartilage during motion squeezes the fluid with lubricating properties from the cartilage. The purpose of the study was to obtain cartilage interstitial fluid (CIF) from intact cartilage and to evaluate its influence on gene expression in the synovial membrane cells...
September 2016: International Journal of Molecular Medicine
Sabrina Jahn, Jasmine Seror, Jacob Klein
The major synovial joints such as hips and knees are uniquely efficient tribological systems, able to articulate over a wide range of shear rates with a friction coefficient between the sliding cartilage surfaces as low as 0.001 up to pressures of more than 100 atm. No human-made material can match this. The means by which such surfaces maintain their very low friction has been intensively studied for decades and has been attributed to fluid-film and boundary lubrication. Here, we focus especially on the latter: the reduction of friction by molecular layers at the sliding cartilage surfaces...
July 11, 2016: Annual Review of Biomedical Engineering
Kirk J Samaroo, Mingchee Tan, David Putnam, Lawrence J Bonassar
The glycoprotein, lubricin, is the primary boundary lubricant of articular cartilage and has been shown to prevent cartilage damage after joint injury. In this study, a library of eight bottle-brush copolymers were synthesized to mimic the structure and function of lubricin. Polyethylene glycol (PEG) grafted onto a polyacrylic acid (pAA) core mimicked the hydrophilic mucin-like domain of lubricin, and a thiol terminus anchored the polymers to cartilage surfaces much like lubricin's C-terminus. These copolymers, abbreviated as pAA-g-PEG, rapidly bound to cartilage surfaces with binding time constants ranging from 20 to 39 min, and affected lubrication under boundary mode conditions with coefficients of friction ranging from 0...
July 15, 2016: Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society
Zenon Pawlak, Adam Gadomski, Michal Sojka, Wieslaw Urbaniak, Piotr Bełdowski
The amphoteric effect on the friction between the bovine cartilage/cartilage contacts has been found to be highly sensitive to the pH of an aqueous solution. The cartilage surface was characterized using a combination of the pH, wettability, as well as the interfacial energy and friction coefficient testing methods to support lamellar-repulsive mechanism of hydration lubrication. It has been confirmed experimentally that phospholipidic multi-bilayers are essentially described as lamellar frictionless lubricants protecting the surface of the joints against wear...
October 1, 2016: Colloids and Surfaces. B, Biointerfaces
Harry M Roberts, Jonathan P Moore, Claire L Griffith-McGeever, Matthew B Fortes, Jeanette M Thom
PURPOSE: Our aim was to investigate lubricin, cartilage oligomeric matrix protein (COMP), and femoral cartilage deformation in response to different biomechanical loading of the knee joint (running vs cycling). METHODS: Serum lubricin and COMP concentrations (enzyme-linked immunosorbent assay), and femoral cartilage thickness (suprapatellar transverse ultrasonography) were determined in 11 male runners (age: 40 ± 6 years; weight: 76 ± 8 kg) and 11 male cyclists (35 ± 12 years; 75 ± 5 kg) at baseline, immediately after, and 30 min after vigorous exercise (time trial: 10-km run or 25-km cycle)...
August 2016: European Journal of Applied Physiology
Bram Peters, Janneke H M Schuurs-Hoeijmakers, Joris Fuijkschot, Annette Reimer, Michiel van der Flier, Dorien Lugtenberg, Esther P A H Hoppenreijs
BACKGROUND: Camptodactyly-arthropathy-coxa vara-pericarditis (CACP, OMIM: #208250) syndrome is a rare autosomal recessive disease that can be difficult to recognise not only because of its wide clinical variability but also because of its clinical resemblance to juvenile idiopathic arthritis (JIA). PRG4 is the only gene so far known to be associated with CACP syndrome. Children with CACP syndrome lack the glycoprotein lubricin due to recessive mutations in PRG4. Lubricin serves as a lubricant in joints, tendons and visceral cavities (pleural cavity, pericardium) and inhibits synovial proliferation...
2016: Pediatric Rheumatology Online Journal
Heidi L Reesink, Edward D Bonnevie, Sherry Liu, Carolyn R Shurer, Michael J Hollander, Lawrence J Bonassar, Alan J Nixon
Lubricin is a mucinous, synovial fluid glycoprotein that enables near frictionless joint motion via adsorption to the surface of articular cartilage and its lubricating properties in solution. Extensive O-linked glycosylation within lubricin's mucin-rich domain is critical for its boundary lubricating function; however, it is unknown exactly how glycosylation facilitates cartilage lubrication. Here, we find that the lubricin glycome is enriched with terminal β-galactosides, known binding partners for a family of multivalent lectins called galectins...
2016: Scientific Reports
Giovanna Nalesso, Bethan Lynne Thomas, Joanna Claire Sherwood, Jing Yu, Olga Addimanda, Suzanne Elizabeth Eldridge, Anne-Sophie Thorup, Leslie Dale, Georg Schett, Jochen Zwerina, Noha Eltawil, Costantino Pitzalis, Francesco Dell'Accio
OBJECTIVE: Both excessive and insufficient activation of WNT signalling results in cartilage breakdown and osteoarthritis. WNT16 is upregulated in the articular cartilage following injury and in osteoarthritis. Here, we investigate the function of WNT16 in osteoarthritis and the downstream molecular mechanisms. METHODS: Osteoarthritis was induced by destabilisation of the medial meniscus in wild-type and WNT16-deficient mice. Molecular mechanisms and downstream effects were studied in vitro and in vivo in primary cartilage progenitor cells and primary chondrocytes...
May 4, 2016: Annals of the Rheumatic Diseases
Lu Luo, Adam R O'Reilly, Stephen D Thorpe, Conor T Buckley, Daniel J Kelly
Engineering tissues with a structure and spatial composition mimicking those of native articular cartilage (AC) remains a challenge. This study examined if infrapatellar fat pad-derived stem cells (FPSCs) can be used to engineer cartilage grafts with a bulk composition and a spatial distribution of matrix similar to the native tissue. In an attempt to mimic the oxygen gradients and mechanical environment within AC, FPSC-laden hydrogels (either 2 mm or 4 mm in height) were confined to half of their thickness and/or subjected to dynamic compression (DC)...
May 3, 2016: Journal of Tissue Engineering and Regenerative Medicine
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