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Sample records for articular cartilage chondrocytes

  1. Chondroprotective Effect of Kartogenin on CD44-Mediated Functions in Articular Cartilage and Chondrocytes

    OpenAIRE

    Ono, Yohei; Ishizuka, Shinya; Knudson, Cheryl B.; Knudson, Warren

    2014-01-01

    Objective: A recent report identified the small molecule kartogenin as a chondrogenic and chondroprotective agent. Since changes in hyaluronan metabolism occur during cartilage degeneration in osteoarthritis, we began studies to determine whether there was a connection between extracellular hyaluronan, CD44–hyaluronan interactions and the effects of kartogenin on articular chondrocytes. Methods: Chondrocytes cultured in monolayers, bioengineered neocartilages, or cartilage explants were treat...

  2. 3D Hydrogel Scaffolds for Articular Chondrocyte Culture and Cartilage Generation.

    Science.gov (United States)

    Smeriglio, Piera; Lai, Janice H; Yang, Fan; Bhutani, Nidhi

    2015-01-01

    Human articular cartilage is highly susceptible to damage and has limited self-repair and regeneration potential. Cell-based strategies to engineer cartilage tissue offer a promising solution to repair articular cartilage. To select the optimal cell source for tissue repair, it is important to develop an appropriate culture platform to systematically examine the biological and biomechanical differences in the tissue-engineered cartilage by different cell sources. Here we applied a three-dimensional (3D) biomimetic hydrogel culture platform to systematically examine cartilage regeneration potential of juvenile, adult, and osteoarthritic (OA) chondrocytes. The 3D biomimetic hydrogel consisted of synthetic component poly(ethylene glycol) and bioactive component chondroitin sulfate, which provides a physiologically relevant microenvironment for in vitro culture of chondrocytes. In addition, the scaffold may be potentially used for cell delivery for cartilage repair in vivo. Cartilage tissue engineered in the scaffold can be evaluated using quantitative gene expression, immunofluorescence staining, biochemical assays, and mechanical testing. Utilizing these outcomes, we were able to characterize the differential regenerative potential of chondrocytes of varying age, both at the gene expression level and in the biochemical and biomechanical properties of the engineered cartilage tissue. The 3D culture model could be applied to investigate the molecular and functional differences among chondrocytes and progenitor cells from different stages of normal or aberrant development. PMID:26484414

  3. Chondrocytes, Mesenchymal Stem Cells, and Their Combination in Articular Cartilage Regenerative Medicine.

    Science.gov (United States)

    Nazempour, A; Van Wie, B J

    2016-05-01

    Articular cartilage (AC) is a highly organized connective tissue lining, covering the ends of bones within articulating joints. Its highly ordered structure is essential for stable motion and provides a frictionless surface easing load transfer. AC is vulnerable to lesions and, because it is aneural and avascular, it has limited self-repair potential which often leads to osteoarthritis. To date, no fully successful treatment for osteoarthritis has been reported. Thus, the development of innovative therapeutic approaches is desperately needed. Autologous chondrocyte implantation, the only cell-based surgical intervention approved in the United States for treating cartilage defects, has limitations because of de-differentiation of articular chondrocytes (AChs) upon in vitro expansion. De-differentiation can be abated if initial populations of AChs are co-cultured with mesenchymal stem cells (MSCs), which not only undergo chondrogenesis themselves but also support chondrocyte vitality. In this review we summarize studies utilizing AChs, non-AChs, and MSCs and compare associated outcomes. Moreover, a comprehensive set of recent human studies using chondrocytes to direct MSC differentiation, MSCs to support chondrocyte re-differentiation and proliferation in co-culture environments, and exploratory animal intra- and inter-species studies are systematically reviewed and discussed in an innovative manner allowing side-by-side comparisons of protocols and outcomes. Finally, a comprehensive set of recommendations are made for future studies. PMID:26987846

  4. Flavonoid Compound Icariin Activates Hypoxia Inducible Factor-1α in Chondrocytes and Promotes Articular Cartilage Repair.

    Science.gov (United States)

    Wang, Pengzhen; Zhang, Fengjie; He, Qiling; Wang, Jianqi; Shiu, Hoi Ting; Shu, Yinglan; Tsang, Wing Pui; Liang, Shuang; Zhao, Kai; Wan, Chao

    2016-01-01

    Articular cartilage has poor capability for repair following trauma or degenerative pathology due to avascular property, low cell density and migratory ability. Discovery of novel therapeutic approaches for articular cartilage repair remains a significant clinical need. Hypoxia is a hallmark for cartilage development and pathology. Hypoxia inducible factor-1alpha (HIF-1α) has been identified as a key mediator for chondrocytes to response to fluctuations of oxygen availability during cartilage development or repair. This suggests that HIF-1α may serve as a target for modulating chondrocyte functions. In this study, using phenotypic cellular screen assays, we identify that Icariin, an active flavonoid component from Herba Epimedii, activates HIF-1α expression in chondrocytes. We performed systemic in vitro and in vivo analysis to determine the roles of Icariin in regulation of chondrogenesis. Our results show that Icariin significantly increases hypoxia responsive element luciferase reporter activity, which is accompanied by increased accumulation and nuclear translocation of HIF-1α in murine chondrocytes. The phenotype is associated with inhibiting PHD activity through interaction between Icariin and iron ions. The upregulation of HIF-1α mRNA levels in chondrocytes persists during chondrogenic differentiation for 7 and 14 days. Icariin (10-6 M) increases the proliferation of chondrocytes or chondroprogenitors examined by MTT, BrdU incorporation or colony formation assays. Icariin enhances chondrogenic marker expression in a micromass culture including Sox9, collagen type 2 (Col2α1) and aggrecan as determined by real-time PCR and promotes extracellular matrix (ECM) synthesis indicated by Alcian blue staining. ELISA assays show dramatically increased production of aggrecan and hydroxyproline in Icariin-treated cultures at day 14 of chondrogenic differentiation as compared with the controls. Meanwhile, the expression of chondrocyte catabolic marker genes

  5. Flavonoid Compound Icariin Activates Hypoxia Inducible Factor-1α in Chondrocytes and Promotes Articular Cartilage Repair.

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    Pengzhen Wang

    Full Text Available Articular cartilage has poor capability for repair following trauma or degenerative pathology due to avascular property, low cell density and migratory ability. Discovery of novel therapeutic approaches for articular cartilage repair remains a significant clinical need. Hypoxia is a hallmark for cartilage development and pathology. Hypoxia inducible factor-1alpha (HIF-1α has been identified as a key mediator for chondrocytes to response to fluctuations of oxygen availability during cartilage development or repair. This suggests that HIF-1α may serve as a target for modulating chondrocyte functions. In this study, using phenotypic cellular screen assays, we identify that Icariin, an active flavonoid component from Herba Epimedii, activates HIF-1α expression in chondrocytes. We performed systemic in vitro and in vivo analysis to determine the roles of Icariin in regulation of chondrogenesis. Our results show that Icariin significantly increases hypoxia responsive element luciferase reporter activity, which is accompanied by increased accumulation and nuclear translocation of HIF-1α in murine chondrocytes. The phenotype is associated with inhibiting PHD activity through interaction between Icariin and iron ions. The upregulation of HIF-1α mRNA levels in chondrocytes persists during chondrogenic differentiation for 7 and 14 days. Icariin (10-6 M increases the proliferation of chondrocytes or chondroprogenitors examined by MTT, BrdU incorporation or colony formation assays. Icariin enhances chondrogenic marker expression in a micromass culture including Sox9, collagen type 2 (Col2α1 and aggrecan as determined by real-time PCR and promotes extracellular matrix (ECM synthesis indicated by Alcian blue staining. ELISA assays show dramatically increased production of aggrecan and hydroxyproline in Icariin-treated cultures at day 14 of chondrogenic differentiation as compared with the controls. Meanwhile, the expression of chondrocyte catabolic

  6. Type II collagen peptide is able to accelerate embryonic chondrocyte differentiation: an association with articular cartilage matrix resorption in osteoarthrosis

    Directory of Open Access Journals (Sweden)

    Elena Vasil'evna Chetina

    2010-01-01

    Conclusion. The effect of CP on gene expression and collagen decomposition activity depends on the morphotype of embryonic chondrocytes. Lack of effect of CP on collagen decomposition activity in both the embryonic hypertrophic chondrocytes and the cartilage explants from OA patients supports the hypothesis that the hypertrophic morphotype is a dominant morphotype of articular chondrocytes in OA. Moreover, collagen decomposition products can be involved in the resorption of matrix in OA and in the maintenance of chronic nature of the pathology.

  7. Quantitative analysis of rough endoplasmic reticulum in chondrocytes of articular and tracheal cartilage of rabbits following the systemic administration of hydrocortisone.

    OpenAIRE

    T. Itani; Kanai, K.; Watanabe, J.; Ogawa, R; Kanamura, S

    1992-01-01

    The rough endoplasmic reticulum (RER) in chondrocytes was analysed stereologically in articular cartilage of knee joints and in tracheal cartilage of rabbits injected intramuscularly with 5 mg/kg hydrocortisone daily for 4 wk. In articular cartilage, RER area per unit cytoplasmic volume decreased in chondrocytes in all (superficial, middle and deep) zones, although the volume of glycogen deposits per unit cytoplasmic volume increased in the middle and deep zones. RER area per chondrocyte also...

  8. Reactive oxygen species induce expression of vascular endothelial growth factor in chondrocytes and human articular cartilage explants

    OpenAIRE

    Fay, Jakob; Varoga, Deike; Wruck, Christoph J.; Kurz, Bodo; Goldring, Mary B.; Pufe, Thomas

    2006-01-01

    Vascular endothelial growth factor (VEGF) promotes cartilage-degrading pathways, and there is evidence for the involvement of reactive oxygen species (ROS) in cartilage degeneration. However, a relationship between ROS and VEGF has not been reported. Here, we investigate whether the expression of VEGF is modulated by ROS. Aspirates of synovial fluid from patients with osteoarthritis (OA) were examined for intra-articular VEGF using ELISA. Immortalized C28/I2 chondrocytes and human knee cartil...

  9. Articular chondrocytes and mesenchymal stem cells seeded on biodegradable scaffolds for the repair of cartilage in a rat osteochondral defect model.

    Science.gov (United States)

    Dahlin, Rebecca L; Kinard, Lucas A; Lam, Johnny; Needham, Clark J; Lu, Steven; Kasper, F Kurtis; Mikos, Antonios G

    2014-08-01

    This work investigated the ability of co-cultures of articular chondrocytes and mesenchymal stem cells (MSCs) to repair articular cartilage in osteochondral defects. Bovine articular chondrocytes and rat MSCs were seeded in isolation or in co-culture onto electrospun poly(ɛ-caprolactone) (PCL) scaffolds and implanted into an osteochondral defect in the trochlear groove of 12-week old Lewis rats. Additionally, a blank PCL scaffold and untreated defect were investigated. After 12 weeks, the extent of cartilage repair was analyzed through histological analysis, and the extent of bone healing was assessed by quantifying the total volume of mineralized bone in the defect through microcomputed tomography. Histological analysis revealed that the articular chondrocytes and co-cultures led to repair tissue that consisted of more hyaline-like cartilage tissue that was thicker and possessed more intense Safranin O staining. The MSC, blank PCL scaffold, and empty treatment groups generally led to the formation of fibrocartilage repair tissue. Microcomputed tomography revealed that while there was an equivalent amount of mineralized bone formation in the MSC, blank PCL, and empty treatment groups, the defects treated with chondrocytes or co-cultures had negligible mineralized bone formation. Overall, even with a reduced number of chondrocytes, co-cultures led to an equal level of cartilage repair compared to the chondrocyte samples, thus demonstrating the potential for the use of co-cultures of articular chondrocytes and MSCs for the in vivo repair of cartilage defects. PMID:24927682

  10. Recombinant equine interleukin-1β induces putative mediators of articular cartilage degradation in equine chondrocytes

    OpenAIRE

    Tung, J. T.; Fenton, J. I.; Arnold, C; Alexander, L.; Yuzbasiyan-Gurkan, V.; Venta, P J; Peters, T. L.; Orth, M W; Richardson, D. W.; Caron, J P

    2002-01-01

    Interleukin-1 is considered a central mediator of cartilage loss in osteoarthritis in several species, however an equine recombinant form of this cytokine is not readily available for in vitro use in equine osteoarthritis research. Equine recombinant interleukin-1β was cloned and expressed and its effects on the expression and activity of selected chondrocytic proteins implicated in cartilage matrix degradation were characterized. Reverse transcriptase polymerase chain reaction methods were u...

  11. Green fluorescent protein as marker in chondrocytes overexpressing human insulin-like growth factor-1 for repair of articular cartilage defects in rabbits

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shao-kun; LIU Yi; SONG Zhi-ming; FU Chang-feng; XU Xin-xiang

    2007-01-01

    Objective:To label the primary articular chondrocytes overexpressing human insulin-like growth factor ( hIGF-1 ) with green fluorescent protein (GFP) for repair of articular cartilage defects in rabbits. Methods:GFP cDNA was inserted into pcDNA3.1-hIGF-1 to label the expression vector.The recombinant vector,pcGI,a mammalian expression vector with multiple cloning sites under two respective cytomegalovirus promoters/enhancers,was transfected into the primary articular chondrocytes with the help of lipofectamine.After the positive cell clones were selected by G418,G418-resistant chondrocytes were cultured in medium for 4 weeks.The stable expression of hIGF-1 in the articular chondrocytes was determined by in situ hybridization and immunocytochemical analysis and the GFP was confirmed under a fluorescence microscope. Methyl thiazolyl tetrazolium (MTT) and flow cytometer methods were employed to determine the effect of transfection on proliferation of chondrocytes. Gray value was used to analyze quantitatively the expression of type Ⅱ collagen. Results:The expression of hIGF-1 and GFP was confirmed in transfected chondrocytes by in situ hybridization, immunocytochemical analysis and fluorescence microscope observation. Green articular chondrocytes overexpressing hIGF-1 could expand and maintain their chondrogenic phenotypes for more than 4 weeks.After the transfection of IGF-1,the proliferation of chondrocytes was enhanced and the chondrocytes could effectively maintain the expression of type Ⅱ collagen. Conclusions:The hIGF-1 eukaryotic expression vector containing GFP marker gene has been successfully constructed.GFP,which can be visualized in real time and in situ, is stably expressed in articular chondrocytes overexpressing hIGF-1.The labeled articular chondrocytes overexpressing hIGF-1 can be applied in cell-mediated gene therapy as well as for other biomedical purposes of transgenic chondrocytes.

  12. ACTIVITY OF CANONICAL WNT SIGNAL SYSTEM IN HYALINE CARTILAGE ARTICULAR CHONDROCYTES IN PROCESS OF SYNOVIAL JOINT DEVELOPMENT

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    A.O. Molotkov

    2009-03-01

    Full Text Available Canonical and non-canonical Wnt systems are essential regulators of chondrogenesis and bone development. However, the roles of these systems in synovial joint development are not well studied. To determine if canonical Wnt system is active in developing articular chondrocytes we used immunohistochemistry for в-galactosidase and doublecortin (cell-type specific marker for articular chondrocytes to double label sections through joint regions of E14.5, E18.5, P10 and adult mice. Here the following results are presented. Canonical Wnt signal system does not work in developing articular chondrocytes at early embryonic stages (E14.5; it is active in the articular chondrocytes at late embryonic stages (E16.5-E18.5 and during postnatal development (P7-P10, but is turned off again in the adult articular chondrocytes. These results suggest that canonical Wnt signaling is being regulated during articular chondrocytes differentiation and joint formation.

  13. EFFECT OF LOW SELENIUM ON CHONDROCYTE DIFFERENTIATION AND DIFFERENTIAL EXPRESSION OF COLLAGEN TYPES Ⅰ , Ⅱ AND X IN ARTICULAR CARTILAGE FROM MINI-PIGS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective According to the distribution of low selenium areas, low nutrition state of the residents and the affecting cartilage growth and articular cartilage of Kashin-Beck Disease(KBD),the chondrocyte differentia- tion and differential expression of collagen types Ⅰ , Ⅱ and Ⅹ in articular cartilage from Chinese mini-pigs treated with low selenium were investigated in order to gain insight into the effects of these conditions on chondrocyte differ- entiation in KBD cartilage. Mothods Eleven male juvenile mini-pigs, aged from 4 weeks to 6 weeks after birth, were divided into 3 groups. The Se content in the diet of the “low Se” group was 0. 035mg/kg diet, and 0. 175 mg/kg diet in the control. For Se-supplemented group 0. 390mg /kg diet was added. The content of Se in blood was assayed at the beginning and at the end of each experiment. Samples of articular cartilage were taken from the right femur condylus, and collagen types Ⅰ , Ⅱ and Ⅹ in articular cartilage were analyzed by immunohistochemistry and in situ hybridization. Results ①All cartilage samples from juvenile mini-pigs fed with low selenium diet revealed a re- duction in type Ⅹ collagen mRNA expression in the hypertrophic chondrocytes as shown by in situ hybridization, and reduced type Ⅹ collagen deposition in the lower hypertrophic zone as shown by immunohistochemistry. ②Addition of selenium to the diet restored the type Ⅹ collagen to normal level. ③Type Ⅱ collagen was evenly distributed over the entire articular cartilage in all experimental and control groups. Type Ⅱ collagen mRNA signals were most prominent in the upper articular layer as well as in the hypertrophic zone in all groups. Type Ⅱ collagen expression was restrict- ed to the zone of endochondral ossification in all experimental groups and the control. Conclusion Low selenium has an down-regulatory role on the synthesis and deposition of collagen type Ⅹ in hypertrophic chondrocytes in articular cartilage of

  14. Imaging of articular cartilage

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    Bhawan K Paunipagar

    2014-01-01

    Full Text Available We tried to review the role of magnetic resonance imaging (MRI in understanding microscopic and morphologic structure of the articular cartilage. The optimal protocols and available spin-echo sequences in present day practice are reviewed in context of common pathologies of articular cartilage. The future trends of articular cartilage imaging have been discussed with their appropriateness. In diarthrodial joints of the body, articular cartilage is functionally very important. It is frequently exposed to trauma, degeneration, and repetitive wear and tear. MRI has played a vital role in evaluation of articular cartilage. With the availability of advanced repair surgeries for cartilage lesions, there has been an increased demand for improved cartilage imaging techniques. Recent advances in imaging strategies for native and postoperative articular cartilage open up an entirely new approach in management of cartilage-related pathologies.

  15. Articular chondrocyte metabolism and osteoarthritis

    Energy Technology Data Exchange (ETDEWEB)

    Leipold, H.R.

    1989-01-01

    The three main objectives of this study were: (1) to determine if depletion of proteoglycans from the cartilage matrix that occurs during osteoarthritis causes a measurable increase of cartilage proteoglycan components in the synovial fluid and sera, (2) to observe what effect intracellular cAMP has on the expression of matrix components by chondrocytes, and (3) to determine if freshly isolated chondrocytes contain detectable levels of mRNA for fibronectin. Canine serum keratan sulfate and hyaluronate were measured to determine if there was an elevation of these serum glycosaminoglycans in a canine model of osteoarthritis. A single intra-articular injection of chymopapain into a shoulder joint increased serum keratan sulfate 10 fold and hyaluronate less than 2 fold in 24 hours. Keratan sulfate concentrations in synovial fluids of dogs about one year old were unrelated to the presence of spontaneous cartilage degeneration in the joints. High keratan sulfate in synovial fluids correlated with higher keratan sulfate in serum. The mean keratan sulfate concentration in sera of older dogs with osteoarthritis was 37% higher than disease-free controls, but the difference between the groups was not statistically significant. Treatment of chondrocytes with 0.5 millimolar (mM) dibutyryl cAMP (DBcAMP) caused the cells to adopt a more rounded morphology. There was no difference between the amount of proteins synthesized by cultures treated with DBcAMP and controls. The amount of fibronectin (FN) in the media of DBcAMP treated cultures detected by an ELISA was specifically reduced, and the amount of {sup 35}S-FN purified by gelatin affinity chromatography decreased. Moreover, the percentage of FN containing the extra domain. A sequence was reduced. Concomitant with the decrease in FN there was an increase in the concentration of keratan sulfate.

  16. Snorc is a novel cartilage specific small membrane proteoglycan expressed in differentiating and articular chondrocytes

    DEFF Research Database (Denmark)

    Heinonen, J; Taipaleenmäki, H; Roering, P; Takatalo, M; Harkness, L; Sandholm, J; Uusitalo-Järvinen, H; Kassem, M; Kiviranta, I; Laitala-Leinonen, T; Säämänen, A-M

    2011-01-01

    expressed in Cos7 cells, and the cell lysate was studied for putative glycosaminoglycan attachment by digestion with chondroitinase ABC and Western blotting. RESULTS: The predicted molecule is a small, 121 amino acids long type I single-pass transmembrane chondroitin sulfate proteoglycan, that contains ER...... signal peptide, lumenal/extracellular domain with several threonines/serines prone to O-N-acetylgalactosamine modification, and a cytoplasmic tail with a Ying-yang site prone to phosphorylation or O-N-acetylglucosamine modification. It is highly conserved in mammals with orthologs in all vertebrate...... models demonstrated similar expression profiles with Sox9, Acan and Col2a1 and up-regulation by BMP-2. Based on its cartilage specific expression, the molecule was named Snorc, (Small NOvel Rich in Cartilage). CONCLUSION: A novel cartilage specific molecule was identified which marks the differentiating...

  17. Dedifferentiated Human Articular Chondrocytes Redifferentiate to a Cartilage-Like Tissue Phenotype in a Poly(ε-Caprolactone/Self-Assembling Peptide Composite Scaffold

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    Lourdes Recha-Sancho

    2016-06-01

    Full Text Available Adult articular cartilage has a limited capacity for growth and regeneration and, with injury, new cellular or biomaterial-based therapeutic platforms are required to promote repair. Tissue engineering aims to produce cartilage-like tissues that recreate the complex mechanical and biological properties found in vivo. In this study, a unique composite scaffold was developed by infiltrating a three-dimensional (3D woven microfiber poly (ε-caprolactone (PCL scaffold with the RAD16-I self-assembling nanofibers to obtain multi-scale functional and biomimetic tissue-engineered constructs. The scaffold was seeded with expanded dedifferentiated human articular chondrocytes and cultured for four weeks in control and chondrogenic growth conditions. The composite constructs were compared to control constructs obtained by culturing cells with 3D woven PCL scaffolds or RAD16-I independently. High viability and homogeneous cell distribution were observed in all three scaffolds used during the term of the culture. Moreover, gene and protein expression profiles revealed that chondrogenic markers were favored in the presence of RAD16-I peptide (PCL/RAD composite or alone under chondrogenic induction conditions. Further, constructs displayed positive staining for toluidine blue, indicating the presence of synthesized proteoglycans. Finally, mechanical testing showed that constructs containing the PCL scaffold maintained the initial shape and viscoelastic behavior throughout the culture period, while constructs with RAD16-I scaffold alone contracted during culture time into a stiffer and compacted structure. Altogether, these results suggest that this new composite scaffold provides important mechanical requirements for a cartilage replacement, while providing a biomimetic microenvironment to re-establish the chondrogenic phenotype of human expanded articular chondrocytes.

  18. Effects of vimentin disruption on the mechanoresponses of articular chondrocyte.

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    Chen, Cheng; Yin, Li; Song, Xiongbo; Yang, Hao; Ren, Xiang; Gong, Xiaoyuan; Wang, Fuyou; Yang, Liu

    2016-01-01

    Human articular cartilage is subjected to repetitive mechanical loading during life time. As the only cellular component of articular cartilage, chondrocytes play a key role in the mechanotransduction within this tissue. The mechanoresponses of chondrocytes are largely determined by the cytoskeleton. Vimentin intermediate filaments, one of the major cytoskeletal components, have been shown to regulate chondrocyte phenotype. However, the contribution of vimentin in chondrocyte mechanoresponses remains less studied. In this study, we seeded goat articular chondrocytes on a soft polyacrylamide gel, and disrupted the vimentin cytoskeleton using acrylamide. Then we applied a transient stretch or compression to the cells, and measured the changes of cellular stiffness and traction forces using Optical Magnetic Twisting Cytometry and Traction Force Microscopy, respectively. In addition, to study the effects of vimentin disruption on the intracellular force generation, we treated the cells with a variety of reagents that are known to increase or decrease cytoskeletal tension. We found that, after a compression, the contractile moment and cellular stiffness were not affected in untreated chondrocytes, but were decreased in vimentin-disrupted chondrocytes; after a stretch, vimentin-disrupted chondrocytes showed a lower level of fluidization-resolidification response compared to untreated cells. Moreover, vimentin-disrupted chondrocytes didn't show much difference to control cells in responding to reagents that target actin and ROCK pathway, but showed a weaker response to histamine and isoproterenol. These findings confirmed chondrocyte vimentin as a major contributor in withstanding compressive loading, and its minor role in regulating cytoskeletal tension. PMID:26616052

  19. Articular cartilage stem cell signalling

    OpenAIRE

    Karlsson, Camilla; Lindahl, Anders

    2009-01-01

    The view of articular cartilage as a non-regeneration organ has been challenged in recent years. The articular cartilage consists of distinct zones with different cellular and molecular phenotypes, and the superficial zone has been hypothesized to harbour stem cells. Furthermore, the articular cartilage demonstrates a distinct pattern regarding stem cell markers (that is, Notch-1, Stro-1, and vascular cell adhesion molecule-1). These results, in combination with the positive identification of...

  20. Colonies in engineered articular cartilage express superior differentiation.

    Science.gov (United States)

    Selvaratnam, L; Abd Rahim, S; Kamarul, T; Chan, K Y; Sureshan, S; Penafort, R; Ng, C L L

    2005-07-01

    In view of poor regeneration potential of the articular cartilage, in-vitro engineering of cartilage tissue offers a promising option for progressive joint disease. This study aims to develop a biologically engineered articular cartilage for autologous transplantation. The initial work involved determination of chondrocyte yield and viability, and morphological analysis. Cartilage was harvested from the knee, hip and shoulder joints of adult New Zealand white rabbits and chondrocytes were isolated by enzymatic digestion of the extra-cellular matrix before serial cultivation in DMEM/Ham's F12 media as monolayer cultures. No differences were noted in cell yield. Although chondrocytes viability was optimal (>93%) following harvest from native cartilage, their viability tended to be lowered on passaging. Chondrocytes aggregated in isogenous colonies comprising ovoid cells with intimate intracellular contacts and readily exhibited Safranin-O positive matrix; features typically associated with articular cartilage in-vivo. However, chondrocytes also existed concurrently in scattered bipolar/multipolar forms lacking Safranin-O expression. Therefore, early data demonstrated successful serial culture of adult chondrocytes with differentiated morphology seen in established chondrocyte colonies synthesizing matrix proteoglycans. PMID:16381284

  1. Engineering articular cartilage using newly developed carrageenan basedhydrogels

    OpenAIRE

    Popa, Elena Geta

    2014-01-01

    Articular cartilage holds specific functionality in the human body creating smooth gliding areas and allowing the joints to move easily without pain. However, due to its avascular nature and to the low metabolic activity of the constituent cells-the chondrocytes, cartilage has a low regenerative potential. The current surgical options to treat damaged cartilage are not long lasting and involve frequent revisions. Tissue engineering may provide an alternative approach for cartilage...

  2. Fracture of articular cartilage.

    Science.gov (United States)

    Chin-Purcell, M V; Lewis, J L

    1996-11-01

    Crack formation and propagation is a significant element of the degeneration process in articular cartilage. In order to understand this process, and separate the relative importance of structural overload and material failure, methods for measuring the fracture toughness of cartilage are needed. In this paper, two such methods are described and used to measure fracture properties of cartilage from the canine patella. A modified single edge notch (MSEN) specimen was used to measure J, and a trouser tear test was used to measure T, both measures of fracture toughness with units of kN/m. A pseudo-elastic modulus was also obtained from the MSEN test. Several potential error sources were examined, and results for the MSEN test compared with another method for measuring the fracture parameter for urethane rubber. Good agreement was found. The two test methods were used to measure properties of cartilage from the patellae of 12 canines: 4-9 specimens from each of 12 patellae, with 5 right-left pairs were tested. Values of J ranged from 0.14-1.2 kN/m. J values correlated with T and were an average of 1.7 times larger than T. A variety of failure responses was seen in the MSEN tests, consequently a grade of 0 to 3 was assigned to each test, where 0 represented a brittle-like crack with minimal opening and 3 represented plastic flow with no crack formation. The initial cracks in 12/82 specimens did not propagate and were assigned to grade 3. The method for reducing data in the MSEN test assumed pseudo-elastic response and could not be used for the grade 3 specimens. Stiffness did not correlate with J. Neither J nor T was statistically different between right-left pairs, but varied between animals. The test methods appear useful for providing a quantitative measure of fracture toughness for cartilage and other soft materials. PMID:8950659

  3. Induced superficial chondrocyte death reduces catabolic cartilage damage in murine posttraumatic osteoarthritis.

    Science.gov (United States)

    Zhang, Minjie; Mani, Sriniwasan B; He, Yao; Hall, Amber M; Xu, Lin; Li, Yefu; Zurakowski, David; Jay, Gregory D; Warman, Matthew L

    2016-08-01

    Joints that have degenerated as a result of aging or injury contain dead chondrocytes and damaged cartilage. Some studies have suggested that chondrocyte death precedes cartilage damage, but how the loss of chondrocytes affects cartilage integrity is not clear. In this study, we examined whether chondrocyte death undermines cartilage integrity in aging and injury using a rapid 3D confocal cartilage imaging technique coupled with standard histology. We induced autonomous expression of diphtheria toxin to kill articular surface chondrocytes in mice and determined that chondrocyte death did not lead to cartilage damage. Moreover, cartilage damage after surgical destabilization of the medial meniscus of the knee was increased in mice with intact chondrocytes compared with animals whose chondrocytes had been killed, suggesting that chondrocyte death does not drive cartilage damage in response to injury. These data imply that chondrocyte catabolism, not death, contributes to articular cartilage damage following injury. Therefore, therapies targeted at reducing the catabolic phenotype may protect against degenerative joint disease. PMID:27427985

  4. Derepression of miRNA-138 contributes to loss of the human articular chondrocyte phenotype

    OpenAIRE

    Seidl, C; Martinez-Sanchez, A; Murphy, CL

    2016-01-01

    Objective: To investigate the function of microRNA-138 (miR-138) in human articular chondrocytes (HACs). Methods: The expression of miR-138 in intact cartilage and cultured chondrocytes and the effects of miR-138 overexpression on chondrocyte marker genes were investigated. Targets of miR-138 relevant to chondrocytes were identified and verified by overexpression of synthetic miRNA mimics and inhibitors, luciferase assays, chromatin immunoprecipitation, and RNA immunoprecipitation o...

  5. Articular cartilage: from formation to tissue engineering.

    Science.gov (United States)

    Camarero-Espinosa, Sandra; Rothen-Rutishauser, Barbara; Foster, E Johan; Weder, Christoph

    2016-05-26

    Hyaline cartilage is the nonlinear, inhomogeneous, anisotropic, poro-viscoelastic connective tissue that serves as friction-reducing and load-bearing cushion in synovial joints and is vital for mammalian skeletal movements. Due to its avascular nature, low cell density, low proliferative activity and the tendency of chondrocytes to de-differentiate, cartilage cannot regenerate after injury, wear and tear, or degeneration through common diseases such as osteoarthritis. Therefore severe damage usually requires surgical intervention. Current clinical strategies to generate new tissue include debridement, microfracture, autologous chondrocyte transplantation, and mosaicplasty. While articular cartilage was predicted to be one of the first tissues to be successfully engineered, it proved to be challenging to reproduce the complex architecture and biomechanical properties of the native tissue. Despite significant research efforts, only a limited number of studies have evolved up to the clinical trial stage. This review article summarizes the current state of cartilage tissue engineering in the context of relevant biological aspects, such as the formation and growth of hyaline cartilage, its composition, structure and biomechanical properties. Special attention is given to materials development, scaffold designs, fabrication methods, and template-cell interactions, which are of great importance to the structure and functionality of the engineered tissue. PMID:26923076

  6. Dedifferentiated Human Articular Chondrocytes Redifferentiate to a Cartilage-Like Tissue Phenotype in a Poly(ε-Caprolactone)/Self-Assembling Peptide Composite Scaffold

    OpenAIRE

    Lourdes Recha-Sancho; Moutos, Franklin T.; Jordi Abellà; Farshid Guilak; Semino, Carlos E.

    2016-01-01

    Adult articular cartilage has a limited capacity for growth and regeneration and, with injury, new cellular or biomaterial-based therapeutic platforms are required to promote repair. Tissue engineering aims to produce cartilage-like tissues that recreate the complex mechanical and biological properties found in vivo. In this study, a unique composite scaffold was developed by infiltrating a three-dimensional (3D) woven microfiber poly (ε-caprolactone) (PCL) scaffold with the RAD16-I self-asse...

  7. Serum-free media for articular chondrocytes in vitro expansion

    Institute of Scientific and Technical Information of China (English)

    SHAO Xin-xin; Neil A.Duncan; LIN Lin; FU Xin; ZHANG Ji-ying; YU Chang-long

    2013-01-01

    Background In vitro chondrocyte expansion is a major challenge in cell-based therapy for human articular cartilage repair.Classical culture conditions usually use animal serum as a medium supplement,which raises a number of undesirable questions.In the present study,two kinds of defined,serum-free media were developed to expand chondrocytes in monolayer culture for the purpose of cartilage tissue engineering.Methods Bovine chondrocytes were expanded in serum-free media supplemented with fibroblast growth factor-2 and platelet-derived growth factor or fibroblast growth factor-2 and insulin-like growth factor.Expansion culture in a conventional 10% fetal bovine serum (FBS) medium served as control.Fibronectin coating was used to help cell adhesion in serum-free medium.Next,in vitro three-dimensional pellet culture was used to evaluate the chondrocyte capacity.Cell pellets were expanded in different media to re-express the differentiated phenotype (re-differentiation) and to form cartilaginous tissue.The pellets were assessed by glycosaminoglycans contents,collagen II,collagen I and collagen X immunohistological staining.Results Chondrocytes cultured in serum-free media showed no proliferation difference than cells grown with 10% FBS medium.In addition,chondrocytes expanded in both serum-free media expressed more differentiated phenotypes at the end of monolayer culture,as indicated by higher gene expression ratios of collagen type Ⅱ to collagen type Ⅰ.Pellets derived from chondrocytes cultured in both serum-free media displayed comparable chondrogenic capacities to pellets from cells expanded in 10% FBS medium.Conclusion These findings provide alternative culture approaches for chondrocytes in vitro expansion,which may benefit the clinical use of autologous chondrocytes implantation.

  8. Postnatal development of articular cartilage

    NARCIS (Netherlands)

    Turnhout, van M.C.

    2010-01-01

    Articular cartilage (AC) is the thin layer of tissue that covers the ends of the bones in the synovial joints in mammals. Functional adult AC has depth-dependent mechanical properties that are not yet present at birth. These depth-dependent mechanical properties in adult life are the result of a dep

  9. Development of artificial articular cartilage.

    Science.gov (United States)

    Oka, M; Ushio, K; Kumar, P; Ikeuchi, K; Hyon, S H; Nakamura, T; Fujita, H

    2000-01-01

    Attempts have been made to develop an artificial articular cartilage on the basis of a new viewpoint of joint biomechanics in which the lubrication and load-bearing mechanisms of natural and artificial joints are compared. Polyvinyl alcohol hydrogel (PVA-H), 'a rubber-like gel', was investigated as an artificial articular cartilage and the mechanical properties of this gel were improved through a new synthetic process. In this article the biocompatibility and various mechanical properties of the new improved PVA-H is reported from the perspective of its usefulness as an artificial articular cartilage. As regards lubrication, the changes in thickness and fluid pressure of the gap formed between a glass plate and the specimen under loading were measured and it was found that PVA-H had a thicker fluid film under higher pressures than polyethylene (PE) did. The momentary stress transmitted through the specimen revealed that PVA-H had a lower peak stress and a longer duration of sustained stress than PE, suggesting a better damping effect. The wear factor of PVA-H was approximately five times that of PE. Histological studies of the articular cartilage and synovial membranes around PVA-H implanted for 8-52 weeks showed neither inflammation nor degenerative changes. The artificial articular cartilage made from PVA-H could be attached to the underlying bone using a composite osteochondral device made from titanium fibre mesh. In the second phase of this work, the damage to the tibial articular surface after replacement of the femoral surface in dogs was studied. Pairs of implants made of alumina, titanium or PVA-H on titanium fibre mesh were inserted into the femoral condyles. The two hard materials caused marked pathological changes in the articular cartilage and menisci, but the hydrogel composite replacement caused minimal damage. The composite osteochondral device became rapidly attached to host bone by ingrowth into the supporting mesh. The clinical implications of

  10. Role of Chondrocytes in Cartilage Formation, Progression of Osteoarthritis and Cartilage Regeneration

    Science.gov (United States)

    Akkiraju, Hemanth; Nohe, Anja

    2016-01-01

    Articular cartilage (AC) covers the diarthrodial joints and is responsible for the mechanical distribution of loads across the joints. The majority of its structure and function is controlled by chondrocytes that regulate Extracellular Matrix (ECM) turnover and maintain tissue homeostasis. Imbalance in their function leads to degenerative diseases like Osteoarthritis (OA). OA is characterized by cartilage degradation, osteophyte formation and stiffening of joints. Cartilage degeneration is a consequence of chondrocyte hypertrophy along with the expression of proteolytic enzymes. Matrix Metalloproteinases (MMPs) and A Disintegrin and Metalloproteinase with Thrombospondin Motifs (ADAMTS) are an example of these enzymes that degrade the ECM. Signaling cascades involved in limb patterning and cartilage repair play a role in OA progression. However, the regulation of these remains to be elucidated. Further the role of stem cells and mature chondrocytes in OA progression is unclear. The progress in cell based therapies that utilize Mesenchymal Stem Cell (MSC) infusion for cartilage repair may lead to new therapeutics in the long term. However, many questions are unanswered such as the efficacy of MSCs usage in therapy. This review focuses on the role of chondrocytes in cartilage formation and the progression of OA. Moreover, it summarizes possible alternative therapeutic approaches using MSC infusion for cartilage restoration. PMID:27347486

  11. Nanocomposite Scaffold for Chondrocyte Growth and Cartilage Tissue Engineering: Effects of Carbon Nanotube Surface Functionalization

    OpenAIRE

    Chahine, Nadeen O.; Collette, Nicole M.; Thomas, Cynthia B.; Genetos, Damian C.; Loots, Gabriela G

    2014-01-01

    The goal of this study was to assess the long-term biocompatibility of single-wall carbon nanotubes (SWNTs) for tissue engineering of articular cartilage. We hypothesized that SWNT nanocomposite scaffolds in cartilage tissue engineering can provide an improved molecular-sized substrate for stimulation of chondrocyte growth, as well as structural reinforcement of the scaffold's mechanical properties. The effect of SWNT surface functionalization (-COOH or -PEG) on chondrocyte viability and bioc...

  12. Growth differentiation factor-5 stimulates the growth and anabolic metabolism of articular chondrocytes

    Institute of Scientific and Technical Information of China (English)

    Xu Peng; Guo Xiong; Yao Jianfeng; Zhang Yingang; Klaus von der Mark

    2005-01-01

    Objective: To observe the effect of growth differentiation factor-5 (GDF-5) on the growth and anabolic metabolism of articular chondrocytes. Methods: The articular chondrocytes isolated from rats were treated with various concentrations of rmGDF-5, and the growth of chondrocytes measured by MTT assay, the cellular cartilage matrices formation detected sulfated glycosaminoglycan by Alcian blue staining and type Ⅱ collagen by RT-PCR,the collagen phenotypic expression of chondrocytes detected by immunofluorescence. Results: After 7 days culture,MTT assay showed that GDF-5 enhanced the growth of chondrocytes in a dose-dependent manner, RT-PCR showed that GDF-5 clearly induced the synthesis of type Ⅱ collagen because of the col2a1 mRNA band more and more strong in a dose-dependent. Chondrocytes were cultured with GDF-5 for 14 days, the intensity of Alcian blue staining was greatly enhanced, especially, at a high concentration of 1000ng/ml, and GDF-5 enhanced the accumulation of the Alcian blue-stainable material in a concentration-dependent manner and in a does-dependent manner. Chondrocytes were cultured with GDF-5 for 21 days, immunofluorescent staining of type Ⅱ collagen was clear, the type Ⅰ and X collagen were negative. Conclusion: GDF-5 enhanced the growth of mature articular chondrocytes, and stimulated the cellular cartilage matrices formation, but did not change the collagen phenotypic expression of chondrocytes in mono-layer culture.

  13. Implication of interleukin 18 in production of matrix metalloproteinases in articular chondrocytes in arthritis: direct effect on chondrocytes may not be pivotal

    OpenAIRE

    Dai, S.; Shan, Z; Nishioka, K.; Yudoh, K

    2005-01-01

    Objective: To clarify the effect of interleukin (IL) 18 on cartilage degeneration by studying the profile of IL18 receptor (IL18R) on chondrocytes and the direct effect of IL18 on production of matrix metalloproteinases (MMPs), aggrecanases, and tissue inhibitors of metalloproteinases (TIMPs) in articular chondrocytes.

  14. Nanosized fibers' effect on adult human articular chondrocytes behavior

    International Nuclear Information System (INIS)

    Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. - Highlights: ► Chondrocyte behavior in nanofiber-coated microfiber versus microfiber scaffolds ► High porosity (> 90%) and large pore sizes (a few hundred μm) of nanofibrous scaffolds ► Proliferation enhanced by presence of nanofibers ► Differentiation not significantly affected ► Cell attachment improved in presence of both nanofibers and serum

  15. One intra-articular injection of hyaluronan prevents cell death and improves cell metabolism in a model of injured articular cartilage in the rabbit

    NARCIS (Netherlands)

    Jansen, Edwin J. P.; Ernans, Pieter J.; Douw, Conny M.; Guidemond, Nick A.; Van Rhijn, Lodewijk W.; Bulstra, Sjoerd K.; Kuijer, Roell

    2008-01-01

    The purpose of this study was to determine the effect of one intra-articular injection of hyaluronan on chondrocyte death and metabolism in injured cartilage. Twenty-three 6-month-old rabbits received partial-thickness articular cartilage defects created on each medial femoral condyle. In order to e

  16. Advances in the Surgical Management of Articular Cartilage Defects

    OpenAIRE

    Stein, Spencer; Strauss, Eric; Bosco, Joseph

    2013-01-01

    Objective: The purpose of this review is to gain insight into the latest methods of articular cartilage implantation (ACI) and to detail where they are in the Food and Drug Administration approval and regulatory process. Design: A PubMed search was performed using the phrase “Autologous Chondrocyte Implantation” alone and with the words second generation and third generation. Additionally, clinicaltrials.gov was searched for the names of the seven specific procedures and the parent company we...

  17. Growth Differentiation Factor-5 Stimulates the Growth and Anabolic Metabolism of Articular Chondrocytes

    Institute of Scientific and Technical Information of China (English)

    Xu Peng; Yao Jianfeng; Guo Xiong; Zhang Yingang; Klaus von der Mark

    2009-01-01

    Objective: To observe the effect of growth differentiation factor-5 (GDF-5) on the growth and anabolic metabolism of articular chondrocytes. Methods: The articular chondrocytes isolated from rats were treated with various concentrations of rmGDF-5, and the growth of chondrocytes measured by MTr assay, the cellular cartilage matrices formation detected sulfated glycosaminoglycan by Alcian blue staining and type 11 collagen by RT-PCR, the collagen phenotypic expression of chondrocytes detected by immunofluorescence. Results: After 7 days culture, MTF assay showed that GDF-5 enhanced the growth of ehondrocytes in a dose-dependent manner, RT-PCR showed that GDF-5 clearly induced the synthesis of type Ⅱ collagen because of the colal mRNA band more and more strong in a dose-dependent. Chondrocytes were cultured with GDF-5 for 14 days, the intensity of Alcian blue staining was gready enhanced, especially, at a high concentration of 1000ng/ml, and GDF-5 enhanced the accumulation of the Alcian blue-stainable material in a concentration-dependent manner and in a does-dependent manner. Chondrocytes were cultured with GDF-5 for 21 days, immunofluorescent staining of type Ⅱ collagen was clear, the type Ⅰ and Ⅹ collagen were negative. Conclusion: GDF-5 enhanced the growth of mature articular chon-drocytes, and stimulated the cellular cartilage matrices formation, but did not change the collagen phenotypic ex-pression of chondrocytes in mono-layer culture.

  18. Metabolic Effects of Avocado/Soy Unsaponifiables on Articular Chondrocytes

    Directory of Open Access Journals (Sweden)

    Louis Lippiello

    2008-01-01

    Full Text Available Avocado/soy unsaponifiable (ASU components are reported to have a chondroprotective effect by virtue of anti-inflammatory and proanabolic effects on articular chondrocytes. The identity of the active component(s remains unknown. In general, sterols, the major component of unsaponifiable plant material have been demonstrated to be anti-inflammatory in vitro and in animal models. These studies were designed to clarify whether the sterol content of ASU preparations were the primary contributors to biological activity in articular chondrocytes. ASU samples were analyzed by high pressure liquid chromatography (HPLC and GC mass spectrometry. The sterol content was normalized between diverse samples prior to in vitro testing on bovine chondrocytes. Anabolic activity was monitored by uptake of 35-sulfate into proteoglycans and quantitation of labeled hydroxyproline and proline content after incubation with labeled proline. Anti-inflammatory activity was assayed by measuring reduction of interleukin-1 (IL-1-induced synthesis of PGE2 and metalloproteases and release of label from tissue prelabeled with S-35.All ASU samples exerted a similar time-dependent up-regulation of 35-sulfate uptake in bovine cells reaching a maximum of greater than 100% after 72 h at sterol doses of 1–10 μg/ml. Non-collagenous protein (NCP and collagen synthesis were similarly up-regulated. All ASU were equally effective in dose dependently inhibiting IL-1-induced MMP-3 activity (23–37%, labeled sulfate release (15–23% and PGE2 synthesis (45–58%. Up-regulation of glycosaminoglycan and collagen synthesis and reduction of IL-1 effects in cartilage are consistent with chondroprotective activity. The similarity of activity of ASU from diverse sources when tested at equal sterol levels suggests sterols are important for biologic effects in articular chondrocytes.

  19. The use of dynamic culture devices in articular cartilage tissue engineering.

    OpenAIRE

    Akmal, M.

    2006-01-01

    Tissue engineered repair of articular cartilage has now become a clinical reality with techniques for cell culture having advanced from laboratory experimentation to clinical application. Despite the advances in the use of this technology in clinical applications, the basic cell culture techniques for autologous chondrocytes are still based on primitive in-vitro monolayer culture methods. Articular chondrocytes are known to undergo fibroblastic change in monolayer culture as this is not their...

  20. Identification of latexin by a proteomic analysis in rat normal articular cartilage

    Directory of Open Access Journals (Sweden)

    Kouri Juan B

    2010-06-01

    Full Text Available Abstract Background Osteoarthritis (OA is characterized by degeneration of articular cartilage. Animal models of OA induced are a widely used tool in the study of the pathogenesis of disease. Several proteomic techniques for selective extraction of proteins have provided protein profiles of chondrocytes and secretory patterns in normal and osteoarthritic cartilage, including the discovery of new and promising biomarkers. In this proteomic analysis to study several proteins from rat normal articular cartilage, two-dimensional electrophoresis and mass spectrometry (MS were used. Interestingly, latexin (LXN was found. Using an immunohistochemical technique, it was possible to determine its localization within the chondrocytes from normal and osteoarthritic articular cartilage. Results In this study, 147 proteins were visualized, and 47 proteins were identified by MS. A significant proportion of proteins are involved in metabolic processes and energy (32%, as well as participating in different biological functions including structural organization (19%, signal transduction and molecular signaling (11%, redox homeostasis (9%, transcription and protein synthesis (6%, and transport (6%. The identified proteins were assigned to one or more subcellular compartments. Among the identified proteins, we found some proteins already recognized in other studies such as OA-associated proteins. Interestingly, we identified LXN, an inhibitor of mammalian carboxypeptidases, which had not been described in articular cartilage. Immunolabeling assays for LXN showed a granular distribution pattern in the cytoplasm of most chondrocytes of the middle, deep and calcified zones of normal articular cartilage as well as in subchondral bone. In osteoarthritic cartilage, LXN was observed in superficial and deep zones. Conclusions This study provides the first proteomic analysis of normal articular cartilage of rat. We identified LXN, whose location was demonstrated by

  1. Evaluation on Cartilage Morphology after Intra-Articular Injection of Titanium Dioxide Nanoparticles in Rats

    International Nuclear Information System (INIS)

    Nano scale wear particles would generate from orthopedic implants with nano scale surface topography because of residual stress. In this study, the effect of TiO2 nanoparticles on articular cartilage was investigated by intra-articular injection in rats. Using contrast-enhanced high-resolution micro computed tomography (micro-CT) technology, the decreased thickness of articular cartilage in distal femur was determined at 1, 7, 14, and 30 days after nanoparticle exposure. A strong linear correlation (r=0.928, P2 nanoparticles, cartilage thickness showed time-dependent decrease, and cartilage volume was decreased too. Further, the histopathological examination showed the edema chondrocyte and shrinked nucleus in the radial and calcified zone of cartilage. The ultrastructure of articular cartilage implied that the chondrocytes was degenerated, expressing as the condensed chromatin, the dilated endoplasmic reticulum, and the rich mitochondria. Even, the fragments of ruptured endoplasmic reticulum were observed in the cytoplasm of chondrocytes at postexposure day 30. Results indicate that potential damage of articular cartilage was induced by particles existed in knee joint and imply that the bio monitoring should be strengthened in patients with prostheses replacement.

  2. The Regulatory Role of Signaling Crosstalk in Hypertrophy of MSCs and Human Articular Chondrocytes

    Directory of Open Access Journals (Sweden)

    Leilei Zhong

    2015-08-01

    Full Text Available Hypertrophic differentiation of chondrocytes is a main barrier in application of mesenchymal stem cells (MSCs for cartilage repair. In addition, hypertrophy occurs occasionally in osteoarthritis (OA. Here we provide a comprehensive review on recent literature describing signal pathways in the hypertrophy of MSCs-derived in vitro differentiated chondrocytes and chondrocytes, with an emphasis on the crosstalk between these pathways. Insight into the exact regulation of hypertrophy by the signaling network is necessary for the efficient application of MSCs for articular cartilage repair and for developing novel strategies for curing OA. We focus on articles describing the role of the main signaling pathways in regulating chondrocyte hypertrophy-like changes. Most studies report hypertrophic differentiation in chondrogenesis of MSCs, in both human OA and experimental OA. Chondrocyte hypertrophy is not under the strict control of a single pathway but appears to be regulated by an intricately regulated network of multiple signaling pathways, such as WNT, Bone morphogenetic protein (BMP/Transforming growth factor-β (TGFβ, Parathyroid hormone-related peptide (PTHrP, Indian hedgehog (IHH, Fibroblast growth factor (FGF, Insulin like growth factor (IGF and Hypoxia-inducible factor (HIF. This comprehensive review describes how this intricate signaling network influences tissue-engineering applications of MSCs in articular cartilage (AC repair, and improves understanding of the disease stages and cellular responses within an OA articular joint.

  3. Morphological evidence of the shedding of chondrocytes from the articular surface in neonatal rats: relationship to the interlacunar network.

    Science.gov (United States)

    Cole, M B; Narine, K R; Ellinger, J

    1983-08-01

    The superficial zone of the femoral head articular cartilage of 5- to 15-day old rats was examined by light and electron microscopy for evidence of shedding into the joint space. Chondrocytes deepest in the superficial zone were round, surrounded by a capsule, and connected to adjacent chondrocytes by the interlacunar network, whereas cells in the middle of the zone appeared similar but with less cytoplasm. At the circular surface, chondrocytes were small, with pyknotic nuclei and poorly defined organelles. These cells occasionally protruded from the articular surface but maintained at least partial connection with the network and their capsule. Depressions in the articular surface were lined with material similar to that of the network and were the only locations found where the network did not terminate at a cell surface. This static evidence suggested at least two hypotheses: 1) Degenerating chondrocytes moved up through the superficial zone to the articular surface and were shed into the joint space. This movement may be facilitated by the network as part of neonatal cartilage development. 2) During joint formation, the surface of the articular cartilage was eroded down to the chondrocytes, which were exposed to the joint fluid, causing cell degeneration, death, and shedding. Evidence of cell shedding was rarely seen after 2 weeks of age. Likewise, the interlacunar network disappeared from the superficial zone during this period. A physiological as well as structural relationship may exist between the chondrocytes and interlacunar network. PMID:6625202

  4. Lubricin is expressed in chondrocytes derived from osteoarthritic cartilage encapsulated in poly(ethylene glycol diacrylate scaffold

    Directory of Open Access Journals (Sweden)

    G. Musumeci

    2011-09-01

    Full Text Available Osteoarthritis (OA is characterized by degenerative changes within joints that involved quantitative and/or qualitative alterations of cartilage and synovial fluid lubricin, a mucinous glycoprotein secreted by synovial fibroblasts and chondrocytes. Modern therapeutic methods, including tissue-engineering techniques, have been used to treat mechanical damage of the articular cartilage but to date there is no specific and effective treatment. This study aimed at investigating lubricin immunohistochemical expression in cartilage explant from normal and OA patients and in cartilage constructions formed by Poly (ethylene glycol (PEG based hydrogels (PEG-DA encapsulated OA chondrocytes. The expression levels of lubricin were studied by immunohistochemistry: i in tissue explanted from OA and normal human cartilage; ii in chondrocytes encapsulated in hydrogel PEGDA from OA and normal human cartilage. Moreover, immunocytochemical and western blot analysis were performed in monolayer cells from OA and normal cartilage. The results showed an increased expression of lubricin in explanted tissue and in monolayer cells from normal cartilage, and a decreased expression of lubricin in OA cartilage. The chondrocytes from OA cartilage after 5 weeks of culture in hydrogels (PEGDA showed an increased expression of lubricin compared with the control cartilage. The present study demonstrated that OA chondrocytes encapsulated in PEGDA, grown in the scaffold and were able to restore lubricin biosynthesis. Thus our results suggest the possibility of applying autologous cell transplantation in conjunction with scaffold materials for repairing cartilage lesions in patients with OA to reduce at least the progression of the disease.

  5. Advances in treatment of articular cartilage injuries

    Directory of Open Access Journals (Sweden)

    Yuan-cheng LI

    2013-05-01

    Full Text Available Cartilage is a kind of terminally differentiated tissue devoid of vessel or nerve, and it is difficult to repair by itself after damage. Many studies for the treatment of cartilage injuries were performed in recent years aiming at repair of the structure and restoration of its function for injured joint. This article reviews the traditional methods of treatment for cartilage injuries, such as joint lavage with the aid of arthroscope, abrasion chondroplasty, laser abrasion and chondroplasty, and drilling of the subchondral bone-marrow space. The research advances in treatment of articular cartilage injuries with tissue engineering were summarized.

  6. Andrographolide Enhances Proliferation and Prevents Dedifferentiation of Rabbit Articular Chondrocytes: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Li-ke Luo

    2015-01-01

    Full Text Available As the main active constituent of Andrographis paniculata that was applied in treatment of many diseases including inflammation in ancient China, andrographolide (ANDRO was found to facilitate reduction of edema and analgesia in arthritis. This suggested that ANDRO may be promising anti-inflammatory agent to relieve destruction and degeneration of cartilage after inflammation. In this study, the effect of ANDRO on rabbit articular chondrocytes in vitro was investigated. Results showed that not more than 8 μM ANDRO did no harm to chondrocytes (P0.05. The viability assay, hematoxylin-eosin, safranin O, and immunohistochemical staining also showed better performances in ANDRO groups. As to the doses, 3 μM ANDRO showed the best performance. The results indicate that ANDRO can accelerate proliferation of rabbit articular chondrocytes in vitro and meanwhile maintain the phenotype, which may provide valuable references for further exploration on arthritis.

  7. Articular cartilage repair and the evolving role of regenerative medicine

    Directory of Open Access Journals (Sweden)

    Pieter K Bos

    2010-10-01

    Full Text Available Pieter K Bos1, Marloes L van Melle1, Gerjo JVM van Osch1,21Department of Orthopaedic Surgery, Erasmus MC, Rotterdam, the Netherlands; 2Department of Otorhinolaryngology, Erasmus MC, Rotterdam, the NetherlandsAbstract: Among the growing applications of regenerative medicine, clinical articular cartilage repair has now been used for 2 decades and forms a successful example of translational medicine. Cartilage is characterized by a limited intrinsic repair capacity following injury. Articular cartilage defects cause symptoms, are not spontaneously repaired, and are generally believed to result in early osteoarthritis. Marrow stimulation techniques, osteochondral transplantation, and cell-based therapies, such as autologous chondrocyte implantation (ACI and use of mesenchymal stem cells (MSCs, are used for tissue regeneration, symptom relief, and prevention of further joint degeneration. The exact incidence of cartilage defects and the natural outcome of joints with these lesions are unclear. Currently available cartilage repair techniques are designed for defect treatment in otherwise healthy joints and limbs, mostly in young adults. The natural history studies presented in this review estimated that the prevalence of cartilage lesions in this patient group ranges from 5% to 11%. The background and results from currently available randomized clinical trials of the three mostly used cartilage repair techniques are outlined in this review. Osteochondral transplantation, marrow stimulation, and ACI show improvement of symptoms with an advantage for cell-based techniques, but only a suggestion that risk for joint degeneration can be reduced. MSCs, characterized by their good proliferative capacity and the potential to differentiate into different mesenchymal lineages, form an attractive alternative cell source for cartilage regeneration. Moreover, MSCs provide a regenerative microenvironment by the secretion of bioactive factors. This trophic activity

  8. Development of artificial articular cartilage

    Indian Academy of Sciences (India)

    Biswajit Bera

    2009-10-01

    The present study describes the development of artificial articular cartilage on the basis of mimicking structural gel properties and mechanical gel properties of natural articular cartilage. It is synthesized from PVA/Si nanocomposite containing 20% Tetra ethoxy silane (TEOS) by sol–gel method. Mechanical strength of Poly(vinyl alcohol), PVA is improved up to 35 MPa. Manufacturing method is adopted considering colloidal stability of nano silica particle in PVA sol at specific pH = 1. An adhesive is also prepared from PVA/Si nanocomposite containing 40% TEOS for firm attachment of artificial articular cartilage on underlying bone with high bond strength.

  9. Andrographolide Enhances Proliferation and Prevents Dedifferentiation of Rabbit Articular Chondrocytes: An In Vitro Study

    OpenAIRE

    Li-ke Luo; Qing-jun Wei; Lei Liu; Li Zheng; Jin-min Zhao

    2015-01-01

    As the main active constituent of Andrographis paniculata that was applied in treatment of many diseases including inflammation in ancient China, andrographolide (ANDRO) was found to facilitate reduction of edema and analgesia in arthritis. This suggested that ANDRO may be promising anti-inflammatory agent to relieve destruction and degeneration of cartilage after inflammation. In this study, the effect of ANDRO on rabbit articular chondrocytes in vitro was investigated. Results showed that n...

  10. Alterations in periarticular bone and cross talk between subchondral bone and articular cartilage in osteoarthritis.

    Science.gov (United States)

    Goldring, Steven R

    2012-08-01

    The articular cartilage and the subchondral bone form a biocomposite that is uniquely adapted to the transfer of loads across the diarthrodial joint. During the evolution of the osteoarthritic process biomechanical and biological processes result in alterations in the composition, structure and functional properties of these tissues. Given the intimate contact between the cartilage and bone, alterations of either tissue will modulate the properties and function of the other joint component. The changes in periarticular bone tend to occur very early in the development of OA. Although chondrocytes also have the capacity to modulate their functional state in response to loading, the capacity of these cells to repair and modify their surrounding extracellular matrix is relatively limited in comparison to the adjacent subchondral bone. This differential adaptive capacity likely underlies the more rapid appearance of detectable skeletal changes in OA in comparison to the articular cartilage. The OA changes in periarticular bone include increases in subchondral cortical bone thickness, gradual decreases in subchondral trabeular bone mass, formation of marginal joint osteophytes, development of bone cysts and advancement of the zone of calcified cartilage between the articular cartilage and subchondral bone. The expansion of the zone of calcified cartilage contributes to overall thinning of the articular cartilage. The mechanisms involved in this process include the release of soluble mediators from chondrocytes in the deep zones of the articular cartilage and/or the influences of microcracks that have initiated focal remodeling in the calcified cartilage and subchondral bone in an attempt to repair the microdamage. There is the need for further studies to define the pathophysiological mechanisms involved in the interaction between subchondral bone and articular cartilage and for applying this information to the development of therapeutic interventions to improve the

  11. Pregnane X receptor knockout mice display aging-dependent wearing of articular cartilage.

    Directory of Open Access Journals (Sweden)

    Kotaro Azuma

    Full Text Available Steroid and xenobiotic receptor (SXR and its murine ortholog, pregnane X receptor (PXR, are nuclear receptors that are expressed at high levels in the liver and the intestine where they function as xenobiotic sensors that induce expression of genes involved in detoxification and drug excretion. Recent evidence showed that SXR and PXR are also expressed in bone tissue where they mediate bone metabolism. Here we report that systemic deletion of PXR results in aging-dependent wearing of articular cartilage of knee joints. Histomorphometrical analysis showed remarkable reduction of width and an enlarged gap between femoral and tibial articular cartilage in PXR knockout mice. We hypothesized that genes induced by SXR in chondrocytes have a protective effect on articular cartilage and identified Fam20a (family with sequence similarity 20a as an SXR-dependent gene induced by the known SXR ligands, rifampicin and vitamin K2. Lastly, we demonstrated the biological significance of Fam20a expression in chondrocytes by evaluating osteoarthritis-related gene expression of primary articular chondrocytes. Consistent with epidemiological findings, our results indicate that SXR/PXR protects against aging-dependent wearing of articular cartilage and that ligands for SXR/PXR have potential role in preventing osteoarthritis caused by aging.

  12. Pregnane X receptor knockout mice display aging-dependent wearing of articular cartilage.

    Science.gov (United States)

    Azuma, Kotaro; Casey, Stephanie C; Urano, Tomohiko; Horie-Inoue, Kuniko; Ouchi, Yasuyoshi; Blumberg, Bruce; Inoue, Satoshi

    2015-01-01

    Steroid and xenobiotic receptor (SXR) and its murine ortholog, pregnane X receptor (PXR), are nuclear receptors that are expressed at high levels in the liver and the intestine where they function as xenobiotic sensors that induce expression of genes involved in detoxification and drug excretion. Recent evidence showed that SXR and PXR are also expressed in bone tissue where they mediate bone metabolism. Here we report that systemic deletion of PXR results in aging-dependent wearing of articular cartilage of knee joints. Histomorphometrical analysis showed remarkable reduction of width and an enlarged gap between femoral and tibial articular cartilage in PXR knockout mice. We hypothesized that genes induced by SXR in chondrocytes have a protective effect on articular cartilage and identified Fam20a (family with sequence similarity 20a) as an SXR-dependent gene induced by the known SXR ligands, rifampicin and vitamin K2. Lastly, we demonstrated the biological significance of Fam20a expression in chondrocytes by evaluating osteoarthritis-related gene expression of primary articular chondrocytes. Consistent with epidemiological findings, our results indicate that SXR/PXR protects against aging-dependent wearing of articular cartilage and that ligands for SXR/PXR have potential role in preventing osteoarthritis caused by aging. PMID:25749104

  13. Strain-Dependent Oxidant Release in Articular Cartilage Originates from Mitochondria

    OpenAIRE

    J, Brouillette M; S, Ramakrishnan P; M, Wagner V; E, Sauter E; J, Journot B; O, McKinley T; A, Martin J

    2013-01-01

    Mechanical loading is essential for articular cartilage homeostasis and plays a central role in the cartilage pathology, yet the mechanotransduction processes that underlie these effects remain unclear. Previously we showed that lethal amounts of reactive oxygen species (ROS) were liberated from the mitochondria in response to mechanical insult, and that chondrocyte deformation may be a source of ROS. To this end, we hypothesized that mechanically-induced mitochondrial ROS is related to the m...

  14. Synergy between Piezo1 and Piezo2 channels confers high-strain mechanosensitivity to articular cartilage

    Science.gov (United States)

    Lee, Whasil; Leddy, Holly A.; Chen, Yong; Lee, Suk Hee; Zelenski, Nicole A.; McNulty, Amy L.; Wu, Jason; Beicker, Kellie N.; Coles, Jeffrey; Zauscher, Stefan; Grandl, Jörg; Sachs, Frederick; Liedtke, Wolfgang B.

    2014-01-01

    Diarthrodial joints are essential for load bearing and locomotion. Physiologically, articular cartilage sustains millions of cycles of mechanical loading. Chondrocytes, the cells in cartilage, regulate their metabolic activities in response to mechanical loading. Pathological mechanical stress can lead to maladaptive cellular responses and subsequent cartilage degeneration. We sought to deconstruct chondrocyte mechanotransduction by identifying mechanosensitive ion channels functioning at injurious levels of strain. We detected robust expression of the recently identified mechanosensitive channels, PIEZO1 and PIEZO2. Combined directed expression of Piezo1 and -2 sustained potentiated mechanically induced Ca2+ signals and electrical currents compared with single-Piezo expression. In primary articular chondrocytes, mechanically evoked Ca2+ transients produced by atomic force microscopy were inhibited by GsMTx4, a PIEZO-blocking peptide, and by Piezo1- or Piezo2-specific siRNA. We complemented the cellular approach with an explant-cartilage injury model. GsMTx4 reduced chondrocyte death after mechanical injury, suggesting a possible therapy for reducing cartilage injury and posttraumatic osteoarthritis by attenuating Piezo-mediated cartilage mechanotransduction of injurious strains. PMID:25385580

  15. Intra-articular injection of Torin 1 reduces degeneration of articular cartilage in a rabbit osteoarthritis model

    Science.gov (United States)

    Cheng, N-T.; Cui, Y-P.

    2016-01-01

    Objectives Recent studies have shown that systemic injection of rapamycin can prevent the development of osteoarthritis (OA)-like changes in human chondrocytes and reduce the severity of experimental OA. However, the systemic injection of rapamycin leads to many side effects. The purpose of this study was to determine the effects of intra-articular injection of Torin 1, which as a specific inhibitor of mTOR which can cause induction of autophagy, is similar to rapamycin, on articular cartilage degeneration in a rabbit osteoarthritis model and to investigate the mechanism of Torin 1’s effects on experimental OA. Methods Collagenase (type II) was injected twice into both knees of three-month-old rabbits to induce OA, combined with two intra–articular injections of Torin 1 (400 nM). Degeneration of articular cartilage was evaluated by histology using the Mankin scoring system at eight weeks after injection. Chondrocyte degeneration and autophagosomes were observed by transmission electron microscopy. Matrix metallopeptidase-13 (MMP-13) and vascular endothelial growth factor (VEGF) expression were analysed by quantitative RT-PCR (qPCR).Beclin-1 and light chain 3 (LC3) expression were examined by Western blotting. Results Intra-articular injection of Torin 1 significantly reduced degeneration of the articular cartilage after induction of OA. Autophagosomes andBeclin-1 and LC3 expression were increased in the chondrocytes from Torin 1-treated rabbits. Torin 1 treatment also reduced MMP-13 and VEGF expression at eight weeks after collagenase injection. Conclusion Our results demonstrate that intra-articular injection of Torin 1 reduces degeneration of articular cartilage in collagenase-induced OA, at least partially by autophagy activation, suggesting a novel therapeutic approach for preventing cartilage degeneration and treating OA. Cite this article: N-T. Cheng, A. Guo, Y-P. Cui. Intra-articular injection of Torin 1 reduces degeneration of articular cartilage in a

  16. Advanced Strategies for Articular Cartilage Defect Repair

    Directory of Open Access Journals (Sweden)

    Fergal J. O'Brien

    2013-02-01

    Full Text Available Articular cartilage is a unique tissue owing to its ability to withstand repetitive compressive stress throughout an individual’s lifetime. However, its major limitation is the inability to heal even the most minor injuries. There still remains an inherent lack of strategies that stimulate hyaline-like articular cartilage growth with appropriate functional properties. Recent scientific advances in tissue engineering have made significant steps towards development of constructs for articular cartilage repair. In particular, research has shown the potential of biomaterial physico-chemical properties significantly influencing the proliferation, differentiation and matrix deposition by progenitor cells. Accordingly, this highlights the potential of using such properties to direct the lineage towards which such cells follow. Moreover, the use of soluble growth factors to enhance the bioactivity and regenerative capacity of biomaterials has recently been adopted by researchers in the field of tissue engineering. In addition, gene therapy is a growing area that has found noteworthy use in tissue engineering partly due to the potential to overcome some drawbacks associated with current growth factor delivery systems. In this context, such advanced strategies in biomaterial science, cell-based and growth factor-based therapies that have been employed in the restoration and repair of damaged articular cartilage will be the focus of this review article.

  17. Chondrogenic Differentiation of Human Adipose-Derived Stem Cells: A New Path in Articular Cartilage Defect Management?

    Directory of Open Access Journals (Sweden)

    Jan-Philipp Stromps

    2014-01-01

    Full Text Available According to data published by the Centers for Disease Control and Prevention, over 6 million people undergo a variety of medical procedures for the repair of articular cartilage defects in the U.S. each year. Trauma, tumor, and age-related degeneration can cause major defects in articular cartilage, which has a poor intrinsic capacity for healing. Therefore, there is substantial interest in the development of novel cartilage tissue engineering strategies to restore articular cartilage defects to a normal or prediseased state. Special attention has been paid to the expansion of chondrocytes, which produce and maintain the cartilaginous matrix in healthy cartilage. This review summarizes the current efforts to generate chondrocytes from adipose-derived stem cells (ASCs and provides an outlook on promising future strategies.

  18. Nitric oxide compounds have different effects profiles on human articular chondrocyte metabolism

    OpenAIRE

    de Andrés, María C.; Maneiro, Emilia; Martín, Miguel A.; Arenas, Joaquín; Francisco J Blanco

    2013-01-01

    Introduction The pathogenesis of osteoarthritis (OA) is characterized by the production of high amounts of nitric oxide (NO), as a consequence of up-regulation of chondrocyte-inducible nitric oxide synthase (iNOS) induced by inflammatory cytokines. NO donors represent a powerful tool for studying the role of NO in the cartilage in vitro. There is no consensus about NO effects on articular cartilage in part because the differences between the NO donors available. The aim of this work is to com...

  19. Imaging diagnosis of the articular cartilage disorders

    International Nuclear Information System (INIS)

    Objective: To evaluate the diagnosis and differential diagnosis among the chronic osteoarthritis, rheumatoid arthritis and other chronic cartilage lesions on the plain films and MR images. Methods: Eighty-nine cases, including 115 joints, underwent plain film and MRI examination, and enhanced MRI scan was performed on 32 of them, including 44 joints. MRI scan sequences consisted of T1WI, T2WI + PDWI, STIR, and 3D FS SPGR. There were 90 knee joints in this group and each of the articular cartilage was divided into four parts: patella, femoral medial condyle, femoral lateral condyle, and tibia facet on MR images. The cartilage disorders were classified according to the outerbridge method. In addition, 61 cases including 75 joints were observed as a control group on the plain films and MR images. Results: 115 cartilage lesions were found on MR images, in which thinness of the cartilage (58 cases, 50.4%), bone changes under the cartilage (22 cases, 19.7%), medullar edema (22 cases, 19.7%), and synovial hyperplasia (52 cases, 45.2%) were seen. The patella cartilage was the most likely affected part (81/90, 90%). So the patellar cartilage lesions were divided as group 1 (grade I-II) and group 2 (grade III-IV) on MR images, which were compared with the plain film signs. The narrowing of the joint space and saccules under the articular surface were statistically significant with each other, and χ2 values were 9.349 and 9.885, respectively (P=0.002). Conclusion: No constant signs could be seen on the plain films with grade I-II cartilage disorders. While the narrowing joint space and saccules under the joint surface could be seen on them with grade III-IV cartilage disorders, which were mainly correlated with the cartilage disorders and bone changes under the articular cartilages. A combination of the plain films and MR images is the best imaging method for examining the joints and joint cartilages. Enhanced MRI scan is very helpful on the diagnosis and differential

  20. Modeling IL-1 induced degradation of articular cartilage.

    Science.gov (United States)

    Kar, Saptarshi; Smith, David W; Gardiner, Bruce S; Li, Yang; Wang, Yang; Grodzinsky, Alan J

    2016-03-15

    In this study, we develop a computational model to simulate the in vitro biochemical degradation of articular cartilage explants sourced from the femoropatellar grooves of bovine calves. Cartilage explants were incubated in culture medium with and without the inflammatory cytokine IL-1α. The spatio-temporal evolution of the cartilage explant's extracellular matrix components is modelled. Key variables in the model include chondrocytes, aggrecan, collagen, aggrecanase, collagenase and IL-1α. The model is first calibrated for aggrecan homeostasis of cartilage in vivo, then for data on (explant) controls, and finally for data on the IL-1α driven proteolysis of aggrecan and collagen over a 4-week period. The model was found to fit the experimental data best when: (i) chondrocytes continue to synthesize aggrecan during the cytokine challenge, (ii) a one to two day delay is introduced between the addition of IL-1α to the culture medium and subsequent aggrecanolysis, (iii) collagen degradation does not commence until the total concentration of aggrecan (i.e. both intact and degraded aggrecan) at any specific location within the explant becomes ≤1.5 mg/ml and (iv) degraded aggrecan formed due to the IL-1α induced proteolysis of intact aggrecan protects the collagen network while collagen degrades in a two-step process which, together, significantly modulate the collagen network degradation. Under simulated in vivo conditions, the model predicts increased aggrecan turnover rates in the presence of synovial IL-1α, consistent with experimental observations. Such models may help to infer the course of events in vivo following traumatic joint injury, and may also prove useful in quantitatively evaluating the efficiency of various therapeutic molecules that could be employed to avoid or modify the course of cartilage disease states. PMID:26874194

  1. Evolution of Autologous Chondrocyte Repair and Comparison to Other Cartilage Repair Techniques

    Directory of Open Access Journals (Sweden)

    Ashvin K. Dewan

    2014-01-01

    Full Text Available Articular cartilage defects have been addressed using microfracture, abrasion chondroplasty, or osteochondral grafting, but these strategies do not generate tissue that adequately recapitulates native cartilage. During the past 25 years, promising new strategies using assorted scaffolds and cell sources to induce chondrocyte expansion have emerged. We reviewed the evolution of autologous chondrocyte implantation and compared it to other cartilage repair techniques. Methods. We searched PubMed from 1949 to 2014 for the keywords “autologous chondrocyte implantation” (ACI and “cartilage repair” in clinical trials, meta-analyses, and review articles. We analyzed these articles, their bibliographies, our experience, and cartilage regeneration textbooks. Results. Microfracture, abrasion chondroplasty, osteochondral grafting, ACI, and autologous matrix-induced chondrogenesis are distinguishable by cell source (including chondrocytes and stem cells and associated scaffolds (natural or synthetic, hydrogels or membranes. ACI seems to be as good as, if not better than, microfracture for repairing large chondral defects in a young patient’s knee as evaluated by multiple clinical indices and the quality of regenerated tissue. Conclusion. Although there is not enough evidence to determine the best repair technique, ACI is the most established cell-based treatment for full-thickness chondral defects in young patients.

  2. Oxygen, nitric oxide and articular cartilage

    Directory of Open Access Journals (Sweden)

    B Fermor

    2007-04-01

    Full Text Available Molecular oxygen is required for the production of nitric oxide (NO, a pro-inflammatory mediator that is associated with osteoarthritis and rheumatoid arthritis. To date there has been little consideration of the role of oxygen tension in the regulation of nitric oxide production associated with arthritis. Oxygen tension may be particularly relevant to articular cartilage since it is avascular and therefore exists at a reduced oxygen tension. The superficial zone exists at approximately 6% O2, while the deep zone exists at less than 1% O2. Furthermore, oxygen tension can alter matrix synthesis, and the material properties of articular cartilage in vitro.The increase in nitric oxide associated with arthritis can be caused by pro-inflammatory cytokines and mechanical stress. Oxygen tension significantly alters endogenous NO production in articular cartilage, as well as the stimulation of NO in response to both mechanical loading and pro-inflammatory cytokines. Mechanical loading and pro-inflammatory cytokines also increase the production of prostaglandin E2 (PGE2. There is a complex interaction between NO and PGE2, and oxygen tension can alter this interaction. These findings suggest that the relatively low levels of oxygen within the joint may have significant influences on the metabolic activity, and inflammatory response of cartilage as compared to ambient levels. A better understanding of the role of oxygen in the production of inflammatory mediators in response to mechanical loading, or pro-inflammatory cytokines, may aid in the development of strategies for therapeutic intervention in arthritis.

  3. The ECM-Cell Interaction of Cartilage Extracellular Matrix on Chondrocytes

    Directory of Open Access Journals (Sweden)

    Yue Gao

    2014-01-01

    Full Text Available Cartilage extracellular matrix (ECM is composed primarily of the network type II collagen (COLII and an interlocking mesh of fibrous proteins and proteoglycans (PGs, hyaluronic acid (HA, and chondroitin sulfate (CS. Articular cartilage ECM plays a crucial role in regulating chondrocyte metabolism and functions, such as organized cytoskeleton through integrin-mediated signaling via cell-matrix interaction. Cell signaling through integrins regulates several chondrocyte functions, including differentiation, metabolism, matrix remodeling, responses to mechanical stimulation, and cell survival. The major signaling pathways that regulate chondrogenesis have been identified as wnt signal, nitric oxide (NO signal, protein kinase C (PKC, and retinoic acid (RA signal. Integrins are a large family of molecules that are central regulators in multicellular biology. They orchestrate cell-cell and cell-matrix adhesive interactions from embryonic development to mature tissue function. In this review, we emphasize the signaling molecule effect and the biomechanics effect of cartilage ECM on chondrogenesis.

  4. Expression of Transient Receptor Potential Vanilloid (TRPV Channels in Different Passages of Articular Chondrocytes

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    Richard Barrett-Jolley

    2012-04-01

    Full Text Available Ion channels play important roles in chondrocyte mechanotransduction. The transient receptor potential vanilloid (TRPV subfamily of ion channels consists of six members. TRPV1-4 are temperature sensitive calcium-permeable, relatively non-selective cation channels whereas TRPV5 and TRPV6 show high selectivity for calcium over other cations. In this study we investigated the effect of time in culture and passage number on the expression of TRPV4, TRPV5 and TRPV6 in articular chondrocytes isolated from equine metacarpophalangeal joints. Polyclonal antibodies raised against TRPV4, TRPV5 and TRPV6 were used to compare the expression of these channels in lysates from first expansion chondrocytes (P0 and cells from passages 1–3 (P1, P2 and P3 by western blotting. TRPV4, TRPV5 and TRPV6 were expressed in all passages examined. Immunohistochemistry and immunofluorescence confirmed the presence of these channels in sections of formalin fixed articular cartilage and monolayer cultures of methanol fixed P2 chondrocytes. TRPV5 and TRPV6 were upregulated with time and passage in culture suggesting that a shift in the phenotype of the cells in monolayer culture alters the expression of these channels. In conclusion, several TRPV channels are likely to be involved in calcium signaling and homeostasis in chondrocytes.

  5. CCN1 Regulates Chondrocyte Maturation and Cartilage Development.

    Science.gov (United States)

    Zhang, Yongchun; Sheu, Tzong-Jen; Hoak, Donna; Shen, Jie; Hilton, Matthew J; Zuscik, Michael J; Jonason, Jennifer H; O'Keefe, Regis J

    2016-03-01

    WNT/β-CATENIN signaling is involved in multiple aspects of skeletal development, including chondrocyte differentiation and maturation. Although the functions of β-CATENIN in chondrocytes have been extensively investigated through gain-of-function and loss-of-function mouse models, the precise downstream effectors through which β-CATENIN regulates these processes are not well defined. Here, we report that the matricellular protein, CCN1, is induced by WNT/β-CATENIN signaling in chondrocytes. Specifically, we found that β-CATENIN signaling promotes CCN1 expression in isolated primary sternal chondrocytes and both embryonic and postnatal cartilage. Additionally, we show that, in vitro, CCN1 overexpression promotes chondrocyte maturation, whereas inhibition of endogenous CCN1 function inhibits maturation. To explore the role of CCN1 on cartilage development and homeostasis in vivo, we generated a novel transgenic mouse model for conditional Ccn1 overexpression and show that cartilage-specific CCN1 overexpression leads to chondrodysplasia during development and cartilage degeneration in adult mice. Finally, we demonstrate that CCN1 expression increases in mouse knee joint tissues after meniscal/ligamentous injury (MLI) and in human cartilage after meniscal tear. Collectively, our data suggest that CCN1 is an important regulator of chondrocyte maturation during cartilage development and homeostasis. © 2015 American Society for Bone and Mineral Research. PMID:26363286

  6. Oxygen, nitric oxide and articular cartilage

    OpenAIRE

    Fermor, B.; Christensen, S. E.; I Youn; J M Cernanec; C M Davies; Weinberg, J. B.

    2007-01-01

    Molecular oxygen is required for the production of nitric oxide (NO), a pro-inflammatory mediator that is associated with osteoarthritis and rheumatoid arthritis. To date there has been little consideration of the role of oxygen tension in the regulation of nitric oxide production associated with arthritis. Oxygen tension may be particularly relevant to articular cartilage since it is avascular and therefore exists at a reduced oxygen tension. The superficial zone exists at approximately 6% O...

  7. Articular cartilage collagen: an irreplaceable framework?

    OpenAIRE

    Eyre, D. R.; Weis, M A; J-J Wu

    2006-01-01

    Adult articular cartilage by dry weight is two-thirds collagen. The collagen has a unique molecular phenotype. The nascent type II collagen fibril is a heteropolymer, with collagen IX molecules covalently linked to the surface and collagen XI forming the filamentous template of the fibril as a whole. The functions of collagens IX and XI in the heteropolymer are far from clear but, evidently, they are critically important since mutations in COLIX and COLXI genes can result in chondrodysplasia ...

  8. Andrographolide Exerts Chondroprotective Activity in Equine Cartilage Explant and Suppresses Interleukin-1β-Induced MMP-2 Expression in Equine Chondrocyte Culture

    OpenAIRE

    Tangyuenyong, Siriwan; Viriyakhasem, Nawarat; Peansukmanee, Siriporn; Kongtawelert, Prachya; Ongchai, Siriwan

    2014-01-01

    Cartilage erosion in degenerative joint diseases leads to lameness in affected horses. It has been reported that andrographolide from Andrographis paniculata inhibited cartilage matrix-degrading enzymes. This study aimed to explore whether this compound protects equine cartilage degradation in the explant culture model and to determine its effect on matrix metalloproteinase-2 (MMP-2) expression, a matrix-degrading enzyme, in equine chondrocyte culture. Equine articular cartilage explant cultu...

  9. An ovine in vitro model for chondrocyte-based scaffold-assisted cartilage grafts

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    Endres Michaela

    2012-11-01

    Full Text Available Abstract Background Scaffold-assisted autologous chondrocyte implantation is an effective clinical procedure for cartilage repair. From the regulatory point of view, the ovine model is one of the suggested large animal models for pre-clinical studies. The aim of our study was to evaluate the in vitro re-differentiation capacity of expanded ovine chondrocytes in biomechanically characterized polyglycolic acid (PGA/fibrin biomaterials for scaffold-assisted cartilage repair. Methods Ovine chondrocytes harvested from adult articular cartilage were expanded in monolayer and re-assembled three-dimensionally in PGA-fibrin scaffolds. De- and re-differentiation of ovine chondrocytes in PGA-fibrin scaffolds was assessed by histological and immuno-histochemical staining as well as by real-time gene expression analysis of typical cartilage marker molecules and the matrix-remodelling enzymes matrix metalloproteinases (MMP -1, -2 and −13 as well as their inhibitors. PGA scaffolds characteristics including degradation and stiffness were analysed by electron microscopy and biomechanical testing. Results Histological, immuno-histochemical and gene expression analysis showed that dedifferentiated chondrocytes re-differentiate in PGA-fibrin scaffolds and form a cartilaginous matrix. Re-differentiation was accompanied by the induction of type II collagen and aggrecan, while MMP expression decreased in prolonged tissue culture. Electron microscopy and biomechanical tests revealed that the non-woven PGA scaffold shows a textile structure with high tensile strength of 3.6 N/mm2 and a stiffness of up to 0.44 N/mm2, when combined with gel-like fibrin. Conclusion These data suggest that PGA-fibrin is suited as a mechanically stable support structure for scaffold-assisted chondrocyte grafts, initiating chondrogenic re-differentiation of expanded chondrocytes.

  10. Novel aspects to the structure of rabbit articular cartilage

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    ap Gwynn I.

    2002-12-01

    Full Text Available Applying cryo and modified chemical preparation techniques, mainly for scanning electron microscopy, revealed entirely new aspects to the structure of the radial zone of rabbit tibial plateau articular cartilage. The aggrecan component of the extracellular matrix was contained radially in columns, each with a diameter of 1-3mm, by a tightly packed matrix of collagen fibrils. The collagen fibrils were arranged radially, some straight and others in an opposed spiral arrangement, with regularly repeating patterns. This organization existed in the regions surrounding the columns of chondrocytes, known as chondrons. The load bearing property of the tissue was explained by the directed flow and containment of the interstitial fluid, modulated by the protein-carbohydrate complexes, along these collagen bounded tubular structures. The reason why such a structure has not been described previously may be that it is not retained by aldehyde fixation followed by dehydration, the method commonly used for tissue preparation for electron microscopy.

  11. Type III Collagen, a Fibril Network Modifier in Articular Cartilage*

    OpenAIRE

    Wu, Jiann-Jiu; Weis, Mary Ann; Kim, Lammy S.; Eyre, David R.

    2010-01-01

    The collagen framework of hyaline cartilages, including articular cartilage, consists largely of type II collagen that matures from a cross-linked heteropolymeric fibril template of types II, IX, and XI collagens. In the articular cartilages of adult joints, type III collagen makes an appearance in varying amounts superimposed on the original collagen fibril network. In a study to understand better the structural role of type III collagen in cartilage, we find that type III collagen molecules...

  12. Magnetic resonance imaging of articular cartilage at 3 tesla

    International Nuclear Information System (INIS)

    Smooth motor function can be maintained by articular cartilage. When the cartilage is injured, edema occurs, and as degeneration progresses, the cartilage thins and the cartilage matrix decreases. Magnetic resonance (MR) imaging allows noninvasive evaluation of these changes. Fat suppression proton density- and T2-weighted imaging are useful in the morphologic evaluation of articular cartilage. High resolution, 3-tesla MR imaging provides more detailed evaluation. Biochemical information from T2 mapping, T1ρ mapping, and delayed gadolinium-enhanced MR imaging of cartilage (dGEMRIC) is useful for early diagnosis of cartilage injury and evaluation of cartilage repair. The role of MR imaging in evaluating articular cartilage will increase in the future aging society. (author)

  13. Immortalization of human articular chondrocytes and induction of their phenotype

    Institute of Scientific and Technical Information of China (English)

    何清义; 李起鸿; 杨柳; 许建中

    2003-01-01

    Objective To immortalize human articular chondrocytes (HACs) using gene transfection and to maintain stable phenotype of transformed HACs after induction.Methods HACs were transfected with the retroviral vector pLXSN encoding human papillomavirus 16E7 (HPV16E7), and the transformed clones were sorted and proliferated. Karyotype analysis, clone forming tests and nude mice tumor forming tests were applied to check the characteristics of the transformation. Type Ⅱ collagen of transformed chondrocytes was inducted with free serum medium (FSM) supplemented with nutridoma-sp and ascorbate. Results Immortalized HACs were isolated with fifty passages achieved. The HPV16E7 transformed cells were confirmed to be benign. Induction of FSM with nutridoma-sp and ascorbate promoted type Ⅱ collagen of transformed chondrocytes to the high levels of normal chondrocytes. Conclusion HACs transformed with HPV16E7 survive for long periods in vitro, and type Ⅱ collagen can maintain stability after induction.

  14. Mechanical Stress and ATP Synthesis are coupled by Mitochondrial Oxidants in Articular Cartilage

    OpenAIRE

    Wolff, Katherine J; Ramakrishnan, Prem S.; Brouillette, Marc J.; Journot, Brice; Mckinley, Todd O; Buckwalter, JA; Martin, James A.

    2012-01-01

    Metabolic adaptation of articular cartilage under joint loading is evident and matrix synthesis seems to be critically tied to ATP. Chondrocytes utilize the glycolytic pathway for energy requirements but seem to require mitochondrial reactive oxygen species (ROS) to sustain ATP synthesis. The role of ROS in regulating ATP reserves under a mechanically active environment is not clear. It is believed that physiological strains cause deformation of the mitochondria, potentially releasing ROS for...

  15. Linking Cellular and Mechanical Processes in Articular Cartilage Lesion Formation: A Mathematical Model

    OpenAIRE

    Kapitanov, Georgi I.; Wang, Xiayi; Ayati, Bruce P; Brouillette, Marc J.; Martin, James A.

    2016-01-01

    A severe application of stress on articular cartilage can initiate a cascade of biochemical reactions that can lead to the development of osteoarthritis. We constructed a multiscale mathematical model of the process with three components: cellular, chemical, and mechanical. The cellular component describes the different chondrocyte states according to the chemicals these cells release. The chemical component models the change in concentrations of those chemicals. The mechanical component cont...

  16. Phosphorylation of proteoglycans from human articular cartilage

    International Nuclear Information System (INIS)

    Previous studies have shown that sulfated proteoglycans from human articular and epiphyseal cartilage were phosphorylated. These macromolecules contribute to the stiffness and resiliency of this tissue. We demonstrate here that the phosphate moieties are an integral part of proteoglycan subunits. Specifically, evidence is presented which indicates that proteoglycan monomers contain 3 to 4 phosphate moieties per core protein and that these appear to exist as phosphoserine residues. Furthermore, the data illustrate that human articular cartilage also contains more than 20 different phosphoproteins, some of which are closely associated with proteoglycan aggregates. Proteoglycan subunits were purified from extracts of articular cartilage or from media fractions which had been used to label tissue specimens with 32P-orthophosphate. Chemical and radiographic analyses revealed that the phosphate concentration with respect to sulfate and uronic acid content remained constant when purified proteoglycan monomers were subjected to equilibrium ultracentrifugation and size-exclusion chromatography. That the phosphate moieties were bound to proteoglycan monomers via monoester linkages was indicated by the release of 32P-orthophosphate from proteoglycan subunits incubated under mild alkaline conditions or reacted with acid or alkaline phosphatases. Identification of serine residues in the core protein as the sites of phosphorylation was made by autoradiography of thin layer plates on which hydrolyzed samples of purified 32P-proteoglycan subunits had been subjected to 2-dimensional electrophoresis/chromatography. Quantification of 3 to 4 phosphate moieties per core protein of 200,000 daltons was made by chemical analysis of inorganic phosphate released from proteoglycans by acid hydrolysis

  17. Nanosized fibers' effect on adult human articular chondrocytes behavior

    Energy Technology Data Exchange (ETDEWEB)

    Stenhamre, Hanna [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden); Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Thorvaldsson, Anna, E-mail: anna.thorvaldsson@swerea.se [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden); Swerea IVF, Mölndal (Sweden); Enochson, Lars [Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Walkenström, Pernilla [Swerea IVF, Mölndal (Sweden); Lindahl, Anders [Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg (Sweden); Brittberg, Mats [Cartilage Research Unit, University of Gothenburg, Department Orthopaedics, Kungsbacka Hospital, Kungsbacka (Sweden); Gatenholm, Paul [Biopolymer Technology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Gothenburg (Sweden)

    2013-04-01

    Tissue engineering with chondrogenic cell based therapies is an expanding field with the intention of treating cartilage defects. It has been suggested that scaffolds used in cartilage tissue engineering influence cellular behavior and thus the long-term clinical outcome. The objective of this study was to assess whether chondrocyte attachment, proliferation and post-expansion re-differentiation could be influenced by the size of the fibers presented to the cells in a scaffold. Polylactic acid (PLA) scaffolds with different fiber morphologies were produced, i.e. microfiber (MS) scaffolds as well as nanofiber-coated microfiber scaffold (NMS). Adult human articular chondrocytes were cultured in the scaffolds in vitro up to 28 days, and the resulting constructs were assessed histologically, immunohistochemically, and biochemically. Attachment of cells and serum proteins to the scaffolds was affected by the architecture. The results point toward nano-patterning onto the microfibers influencing proliferation of the chondrocytes, and the overall 3D environment having a greater influence on the re-differentiation. In the efforts of finding the optimal scaffold for cartilage tissue engineering, studies as the current contribute to the knowledge of how to affect and control chondrocytes behavior. - Highlights: ► Chondrocyte behavior in nanofiber-coated microfiber versus microfiber scaffolds ► High porosity (> 90%) and large pore sizes (a few hundred μm) of nanofibrous scaffolds ► Proliferation enhanced by presence of nanofibers ► Differentiation not significantly affected ► Cell attachment improved in presence of both nanofibers and serum.

  18. The study on the mechanical characteristics of articular cartilage in simulated microgravity

    Institute of Scientific and Technical Information of China (English)

    Hai-Jun Niu; Qing Wang; Yue-Xiang Wang; Ang Li; Lian-Wen Sun; Yan Yan; Fan Fan; De-Yu Li; Yu-Bo Fan

    2012-01-01

    The microgravity environment of a long-term space flight may induce acute changes in an astronaut's musculo-skeletal systems.This study explores the effects of simulated microgravity on the mechanical characteristics of articular cartilage.Six rats underwent tail suspension for 14 days and six additional rats were kept under normal earth gravity as controls.Swelling strains were measured using high-frequency ultrasound in all cartilage samples subject to osmotic loading.Site-specific swelling strain data were used in a triphasic theoretical model of cartilage swelling to determine the uniaxial modulus of the cartilage solid matrix.No severe surface irregularities were found in the cartilage samples obtained from the control or tail-suspended groups.For the tail-suspended group,the thickness of the cartilage at a specified site,as determined by ultrasound echo,showed a minor decrease.The uniaxial modulus of articular cartilage at the specified site decreased significantly,from (6.31 ± 3.37) MPa to (5.05 ± 2.98) MPa (p < 0.05).The histology-stained image of a cartilage sample also showed a reduced number of chondrocytes and decreased degree of matrix staining.These results demonstrated that the 14 d simulated microgravity induced significant effects on the mechanical characteristics of articular cartilage.This study is the first attempt to explore the effects of simulated microgravity on the mechanical characteristics of articular cartilage using an osmotic loading method and a triphasic model.The conclusions may provide reference information for manned space flights and a better understanding of the effects of microgravity on the skeletal system.

  19. Procyanidin B3 prevents articular cartilage degeneration and heterotopic cartilage formation in a mouse surgical osteoarthritis model.

    Directory of Open Access Journals (Sweden)

    Hailati Aini

    Full Text Available Osteoarthritis (OA is a common disease in the elderly due to an imbalance in cartilage degradation and synthesis. Heterotopic ossification (HO occurs when ectopic masses of endochondral bone form within the soft tissues around the joints and is triggered by inflammation of the soft tissues. Procyanidin B3 (B3 is a procyanidin dimer that is widely studied due to its high abundance in the human diet and antioxidant activity. Here, we evaluated the role of B3 isolated from grape seeds in the maintenance of chondrocytes in vitro and in vivo. We observed that B3 inhibited H(2O(2-induced apoptosis in primary chondrocytes, suppressed H(2O(2- or IL-1ß-induced nitric oxide synthase (iNOS production, and prevented IL-1ß-induced suppression of chondrocyte differentiation marker gene expression in primary chondrocytes. Moreover, B3 treatment enhanced the early differentiation of ATDC5 cells. To examine whether B3 prevents cartilage destruction in vivo, OA was surgically induced in C57BL/6J mice followed by oral administration of B3 or vehicle control. Daily oral B3 administration protected articular cartilage from OA and prevented chondrocyte apoptosis in surgically-induced OA joints. Furthermore, B3 administration prevented heterotopic cartilage formation near the surgical region. iNOS protein expression was enhanced in the synovial tissues and the pseudocapsule around the surgical region in OA mice fed a control diet, but was reduced in mice that received B3. Together, these data indicated that in the OA model, B3 prevented OA progression and heterotopic cartilage formation, at least in a part through the suppression of iNOS. These results support the potential therapeutic benefits of B3 for treatment of human OA and heterotopic ossification.

  20. Novel Elements of the Chondrocyte Stress Response Identified Using an in Vitro Model of Mouse Cartilage Degradation.

    Science.gov (United States)

    Wilson, Richard; Golub, Suzanne B; Rowley, Lynn; Angelucci, Constanza; Karpievitch, Yuliya V; Bateman, John F; Fosang, Amanda J

    2016-03-01

    The destruction of articular cartilage in osteoarthritis involves chondrocyte dysfunction and imbalanced extracellular matrix (ECM) homeostasis. Pro-inflammatory cytokines such as interleukin-1α (IL-1α) contribute to osteoarthritis pathophysiology, but the effects of IL-1α on chondrocytes within their tissue microenvironment have not been fully evaluated. To redress this we used label-free quantitative proteomics to analyze the chondrocyte response to IL-1α within a native cartilage ECM. Mouse femoral heads were cultured with and without IL-1α, and both the tissue proteome and proteins released into the media were analyzed. New elements of the chondrocyte response to IL-1α related to cellular stress included markers for protein misfolding (Armet, Creld2, and Hyou1), enzymes involved in glutathione biosynthesis and regeneration (Gstp1, Gsto1, and Gsr), and oxidative stress proteins (Prdx2, Txn, Atox1, Hmox1, and Vnn1). Other proteins previously not associated with the IL-1α response in cartilage included ECM components (Smoc2, Kera, and Crispld1) and cysteine proteases (cathepsin Z and legumain), while chondroadherin and cartilage-derived C-type lectin (Clec3a) were identified as novel products of IL-1α-induced cartilage degradation. This first proteome-level view of the cartilage IL-1α response identified candidate biomarkers of cartilage destruction and novel targets for therapeutic intervention in osteoarthritis. PMID:26794603

  1. Effects of Chondroitinase ABC-Mediated Proteoglycan Digestion on Decellularization and Recellularization of Articular Cartilage.

    Directory of Open Access Journals (Sweden)

    Catherine A Bautista

    Full Text Available Articular cartilage has a limited capacity to heal itself and thus focal defects often result in the development of osteoarthritis. Current cartilage tissue engineering strategies seek to regenerate injured tissue by creating scaffolds that aim to mimic the unique structure and composition of native articular cartilage. Decellularization is a novel strategy that aims to preserve the bioactive factors and 3D biophysical environment of the native extracellular matrix while removing potentially immunogenic factors. The purpose of this study was to develop a procedure that can enable decellularization and recellularization of intact articular cartilage matrix. Full-thickness porcine articular cartilage plugs were decellularized with a series of freeze-thaw cycles and 0.1% (w/v sodium dodecyl sulfate detergent cycles. Chondroitinase ABC (ChABC was applied before the detergent cycles to digest glycosaminoglycans in order to enhance donor chondrocyte removal and seeded cell migration. Porcine synovium-derived mesenchymal stem cells were seeded onto the decellularized cartilage scaffolds and cultured for up to 28 days. The optimized decellularization protocol removed 94% of native DNA per sample wet weight, while collagen content and alignment were preserved. Glycosaminoglycan depletion prior to the detergent cycles increased removal of nuclear material. Seeded cells infiltrated up to 100 μm into the cartilage deep zone after 28 days in culture. ChABC treatment enhances decellularization of the relatively dense, impermeable articular cartilage by reducing glycosaminoglycan content. ChABC treatment did not appear to affect cell migration during recellularization under static, in vitro culture, highlighting the need for more dynamic seeding methods.

  2. Follistatin Alleviates Synovitis and Articular Cartilage Degeneration Induced by Carrageenan

    Science.gov (United States)

    Yamada, Jun; Abula, Kahaer; Inoue, Makiko; Sekiya, Ichiro; Muneta, Takeshi

    2014-01-01

    Activins are proinflammatory cytokines which belong to the TGFβ superfamily. Follistatin is an extracellular decoy receptor for activins. Since both activins and follistatin are expressed in articular cartilage, we hypothesized that activin-follistatin signaling participates in the process of joint inflammation and cartilage degeneration. To test this hypothesis, we examined the effects of follistatin in a carrageenan-induced mouse arthritis model. Synovitis induced by intra-articular injection of carrageenan was significantly alleviated by preinjection with follistatin. Macrophage infiltration into the synovial membrane was significantly reduced in the presence of follistatin. In addition, follistatin inhibited proteoglycan erosion induced by carrageenan in articular cartilage. These data indicate that activin-follistatin signaling is involved in joint inflammation and cartilage homeostasis. Our data suggest that follistatin can be a new therapeutic target for inflammation-induced articular cartilage degeneration. PMID:25574420

  3. Simultaneous Magnetic Resonance Imaging and Consolidation Measurement of Articular Cartilage

    Directory of Open Access Journals (Sweden)

    Robert Mark Wellard

    2014-05-01

    Full Text Available Magnetic resonance imaging (MRI offers the opportunity to study biological tissues and processes in a non-disruptive manner. The technique shows promise for the study of the load-bearing performance (consolidation of articular cartilage and changes in articular cartilage accompanying osteoarthritis. Consolidation of articular cartilage involves the recording of two transient characteristics: the change over time of strain and the hydrostatic excess pore pressure (HEPP. MRI study of cartilage consolidation under mechanical load is limited by difficulties in measuring the HEPP in the presence of the strong magnetic fields associated with the MRI technique. Here we describe the use of MRI to image and characterize bovine articular cartilage deforming under load in an MRI compatible consolidometer while monitoring pressure with a Fabry-Perot interferometer-based fiber-optic pressure transducer.

  4. Stimulation by concanavalin A of cartilage-matrix proteoglycan synthesis in chondrocyte cultures

    Energy Technology Data Exchange (ETDEWEB)

    Yan, W.Q.; Nakashima, K.; Iwamoto, M.; Kato, Y. (Osaka Univ. (Japan))

    1990-06-15

    The effect of concanavalin A on proteoglycan synthesis by rabbit costal and articular chondrocytes was examined. Chondrocytes were seeded at low density and grown to confluency in medium supplemented with 10% fetal bovine serum, and then the serum concentration was reduced to 0.3%. At the low serum concentration, chondrocytes adopted a fibroblastic morphology. Addition of concanavalin A to the culture medium induced a morphologic alteration of the fibroblastic cells to spherical chondrocytes and increased by 3- to 4-fold incorporation of (35S)sulfate and (3H)glucosamine into large chondroitin sulfate proteoglycan that was characteristically found in cartilage. The stimulation of incorporation of labeled precursors reflected real increases in proteoglycan synthesis, as chemical analyses showed a 4-fold increase in the accumulation of macromolecules containing hexuronic acid in concanavalin A-maintained cultures. Furthermore, the effect of concanavalin A on (35S)sulfate incorporation into proteoglycans was greater than that of various growth factors or hormones. However, concanavalin A had smaller effects on (35S)sulfate incorporation into small proteoglycans and (3H)glucosamine incorporation into hyaluronic acid and chondroitinase AC-resistant glycosaminoglycans. Since other lectins tested, such as wheat germ agglutinin, lentil lectin, and phytohemagglutinin, had little effect on (35S)sulfate incorporation into proteoglycans, the concanavalin A action on chondrocytes seems specific. Although concanavalin A decreased (3H)thymidine incorporation in chondrocytes, the stimulation of proteoglycan synthesis could be observed in chondrocytes exposed to the inhibitor of DNA synthesis, cytosine arabinoside. These results indicate that concanavalin A is a potent modulator of proteoglycan synthesis by chondrocytes.

  5. The determination of apoptosis rates on articular cartilages of ovariectomized rats with and without alendronate treatment.

    Science.gov (United States)

    Acar, Nuray; Balkarli, Huseyin; Soyuncu, Yetkin; Ozbey, Ozlem; Celik-Ozenci, Ciler; Korkusuz, Petek; Ustunel, Ismail

    2016-06-01

    Osteoporosis (OP) is a major health problem characterized by compromised bone strength. Osteoarthritis (OA) is a joint disease that progresses slowly and is characterized by breakdown of the cartilage matrix. Alendronate (ALN), a nitrogen-containing bisphosphonate (BIS), inhibits bone loss and increases bone mineralization, and has been used clinically for the treatment of OP. It is still controversial whether BIS is effective in inhibiting the progression of OA. Chondrocyte apoptosis has been described in both human and experimentally induced OA models. In our study we aimed to detect whether ALN could protect articular cartilage from degeneration and reduce apoptosis rates in experimentally OA induced rats. For this rats were ovariectomized (ovex), nine weeks after operation rats were injected 30 µg/kg/week ALN subcutaneously for six weeks. After six weeks articular cartilages were obtained. We did Safranin O staining and Mankin and Pritzker scorings to evaluate degeneration and investigated the expressions of p53, cleaved caspase 3, Poly ADP-ribose (PAR), Poly ADP-ribose polymerase 1 (PARP 1), and applied TUNEL technique to determine apoptotis rates. We found a significant decrease in glycosaminoglycan (GAG) amount and increased apoptosis which indicates damage on articular cartilages of ovex rats. GAG amount was higher and apoptosis rate was lower on articular cartilages of ALN treated ovex rats compared to the ovex group. In contrary to studies showing that early ALN treatment has a protective effect, our study shows late ALN treatment has a chondroprotective effect on articular cartilage since we treated rats nine weeks after ovariectomy. PMID:26631351

  6. IKKα/CHUK regulates extracellular matrix remodeling independent of its kinase activity to facilitate articular chondrocyte differentiation.

    Directory of Open Access Journals (Sweden)

    Eleonora Olivotto

    remodeling leading to chondrocyte differentiation. Chondrocytes are the unique cell component in articular cartilage, which are quiescent and maintain ECM integrity during tissue homeostasis. In OA, chondrocytes reacquire the capacity to proliferate and differentiate and their activation results in pronounced cartilage degeneration. Τηυσ, our findings are also of potential relevance for defining the onset and/or progression of OA disease.

  7. REGENERATION OF ARTICULAR CARTILAGE UNDER THE IMPLANTATION OF BONE MATRIX

    Directory of Open Access Journals (Sweden)

    Yuri M. Iryanov, Nikolay A. Kiryanov, Olga V. Dyuriagina , Tatiana Yu. Karaseva, Evgenii A. Karasev

    2015-07-01

    Full Text Available Background: The damage or loss of articular cartilage is costly medical problem. The purpose of this work – morphological analysis of reparative chondrogenesis when implanted in the area of the knee joint cartilage of granulated mineralized bone matrix. Material and Methods: The characteristic features of the knee cartilage regeneration studied experimentally in pubertal Wistar rats after modeling a marginal perforated defect and implantation of granulated mineralized bone matrix obtained according to original technology without heat and demineralizing processing into the injury zone. Results: This biomaterial established to have pronounced chondro- and osteoinductive properties, and to provide prolonged activation of reparative process, accelerated organotypical remodeling and restoration of the articular cartilage injured. Conclusion: The data obtained demonstrate the efficacy of МВМ in clinical practice for the treatment of diseases and injuries of the articular cartilage.

  8. The Biological Effects of Sex Hormones on Rabbit Articular Chondrocytes from Different Genders

    OpenAIRE

    Shwu Jen Chang; Shyh Ming Kuo; Yen Ting Lin; Shan-Wei Yang

    2014-01-01

    The aim of this study was to investigate the biological effects of sex hormones (17 β -estradiol and testosterone) on rabbit articular chondrocytes from different genders. We cultured primary rabbit articular chondrocytes from both genders with varying concentration of sex hormones. We evaluate cell proliferation and biochemical functions by MTT and GAG assay. The chondrocyte function and phenotypes were analyzed by mRNA level using RT-PCR. Immunocytochemical staining was also used to evaluat...

  9. Ongoing studies of cell-based therapies for articular cartilage defects in Japan

    Directory of Open Access Journals (Sweden)

    Ogura T

    2014-12-01

    Full Text Available Takahiro Ogura,1 Akihiro Tsuchiya,2 Shuichi Mizuno1 1Department of Orthopedic Surgery, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA; 2Funabashi Orthopaedic Hospital Sports Medicine Center, Funabashi, Chiba, Japan Abstract: Recently, cell-based therapies have generated great interest in the repair of articular cartilage defects and degeneration. Surgical treatments for these indications have multiple options, including marrow stimulation, osteochondral autograft transplant, and autologous chondrocyte implantation. The autologous chondrocyte implantation technique has been improved using a cell scaffold and other devices. Meanwhile, advanced cell-based therapies, including cultured stem cell treatment, have been studied in clinical trials. Most studies have been designed and authorized by institutional review boards and/or the regulatory agencies of the investigators’ countries. For cellular products in regenerative medicine, regulations of many countries are amenable to expedited approval. This paper aims to provide an update on ongoing and prospective cell-based therapies, focusing on articular cartilage injury at designated institutions authorized by the Japanese Pharmaceutical and Medical Device Agency. Keywords: autologous chondrocyte implantation, mesenchymal stem cell, knee joint

  10. Promotion of the articular cartilage proteoglycan degradation by T-2 toxin and selenium protective effect

    Institute of Scientific and Technical Information of China (English)

    Si-yuan LI; Jun-ling CAO; Zhong-li SHI; Jing-hong CHEN; Zeng-tie ZHANG; Clare E. HUGHES; Bruce CATERSON

    2008-01-01

    Objective: To identify the relationship between T-2 toxin and Kashin-Beck disease (KBD), the effects of T-2 toxin on aggrecan metabolism in human chondrocytes and cartilage were investigated in vitro. Methods: Chondrocytes were isolated from human articular cartilage and cultured in vitro. Hyaluronic acid (HA), soluble CD44 (sCD44), IL-1β and TNF-α levels in supernatants were measured by enzyme-linked immunosorbent assay (ELISA). CD44 content in chondrocyte membrane was determined by flow cytometry (FCM). CD44, hyaluronic acid synthetase-2 (HAS-2) and aggrecanases mRNA levels in chondrocytes were determined using reverse transcription polymerase chain reaction (RT-PCR). Immunocytochemical method was used to investigate expressions of BC-13, 3-B-3(-) and 2-B-6 epitopes in the cartilage reconstructed in vitro. Results: T-2 toxin inhibited CD44, HAS-2, and aggrecan mRNA expressions, but promoted aggrecanase-2 mRNA expression. Meanwhile, CD44 expression was found to be the lowest in the chondrocytes cultured with T-2 toxin and the highest in control plus selenium group. In addition,ELISA results indicated that there were higher sCD44, IL-1β and TNF-α levels in T-2 toxin group. Similarly, higher HA levels were also observed in T-2 toxin group using radioimmunoprecipitation assay (RIPA). Furthermore, using monoclonal antibodies BC-13, 3-B-3 and 2-B-6, strong positive immunostaining was found in the reconstructed cartilage cultured with T-2 toxin, whereas no positive staining or very weak staining was observed in the cartilage cultured without T-2 toxin. Selenium could partly inhibit the effects of T-2 toxin above. Conclusion: T-2 toxin could inhibit aggrecan synthesis, promote aggrecanases and pro-inflammatory cytokines production, and consequently induce aggrecan degradation in chondrocytes. These will perturb metabolism balance between aggrecan synthesis and degradation in cartilage, inducing aggrecan loss in the end, which may be the initiation of the cartilage

  11. Experimental articular cartilage repair in the Göttingen minipig

    DEFF Research Database (Denmark)

    Christensen, Bjørn Borsøe; Foldager, Casper Bindzus; Olesen, Morten Lykke;

    2015-01-01

    BACKGROUND: A gold standard treatment for articular cartilage injuries is yet to be found, and a cost-effective and predictable large animal model is needed to bridge the gap between in vitro studies and clinical studies. Ideally, the animal model should allow for testing of clinically relevant...... treatments and the biological response should be reproducible and comparable to humans. This allows for a reliable translation of results to clinical studies.This study aimed at verifying the Göttingen minipig as a pre-clinical model for articular cartilage repair by testing existing clinical cartilage...

  12. Mesenchymal stem cells as a potent cell source for articular cartilage regeneration

    Institute of Scientific and Technical Information of China (English)

    Mohamadreza; Baghaban; Eslaminejad; Elham; Malakooty; Poor

    2014-01-01

    Since articular cartilage possesses only a weak capac-ity for repair, its regeneration potential is considered one of the most important challenges for orthopedic surgeons. The treatment options, such as marrow stimulation techniques, fail to induce a repair tissue with the same functional and mechanical properties of native hyaline cartilage. Osteochondral transplantation is considered an effective treatment option but is as-sociated with some disadvantages, including donor-site morbidity, tissue supply limitation, unsuitable mechani-cal properties and thickness of the obtained tissue. Although autologous chondrocyte implantation results in reasonable repair, it requires a two-step surgical pro-cedure. Moreover, chondrocytes expanded in culture gradually undergo dedifferentiation, so lose morpho-logical features and specialized functions. In the search for alternative cells, scientists have found mesenchymal stem cells(MSCs) to be an appropriate cellular mate-rial for articular cartilage repair. These cells were origi-nally isolated from bone marrow samples and further investigations have revealed the presence of the cells in many other tissues. Furthermore, chondrogenic dif-ferentiation is an inherent property of MSCs noticedat the time of the cell discovery. MSCs are known to exhibit homing potential to the damaged site at which they differentiate into the tissue cells or secrete a wide spectrum of bioactive factors with regenerative proper-ties. Moreover, these cells possess a considerable im-munomodulatory potential that make them the general donor for therapeutic applications. All of these topics will be discussed in this review.

  13. Age-related differential gene and protein expression in postnatal cartilage canal and osteochondral junction chondrocytes.

    Science.gov (United States)

    Duesterdieck-Zellmer, Katja; Semevolos, Stacy; Kinsley, Marc; Riddick, Tara

    2015-01-01

    Wnt/β-catenin, Indian hedgehog (Ihh)/Parathyroid-related peptide (PTHrP) and retinoid signaling pathways regulate cartilage differentiation, growth, and function during development and play a key role in endochondral ossification. The objective of this study was to elucidate the gene and protein expression of signaling molecules of these regulatory pathways in chondrocytes surrounding cartilage canals and the osteochondral junction during neonatal and pre-adolescent development. This study revealed cell-specific and age-related differences in gene and protein expression of signaling molecules of these regulatory pathways. A trend for higher gene expression of PTHrP along the cartilage canals and Ihh along the osteochondral junction suggests the presence of paracrine feedback in articular-epiphyseal cartilage. Differential expression of canonical (β-catenin, Wnt-4, Lrp4, Lrp6) and noncanonical Wnt signaling (Wnt-5b, Wnt-11) and their inhibitors (Dkk1, Axin1, sFRP3, sFRP5, Wif-1) surrounding the cartilage canals and osteochondral junction provides evidence of the complex interactions occurring during endochondral ossification. PMID:25479004

  14. Study of the collagen structure in the superficial zone and physiological state of articular cartilage using a 3D confocal imaging technique

    Directory of Open Access Journals (Sweden)

    Zheng Ming H

    2008-07-01

    the collagen network in the superficial zone during early physiological alteration of articular cartilage. The fibre confocal imaging technology used in this study has allowed developing confocal arthroscopy for in vivo studying the chondrocytes in different depth of articular cartilage. Therefore, the current study has potential to develop an in vivo 3D histology for diagnosis of early osteoarthritis.

  15. Three-year clinical outcome after chondrocyte transplantation using a hyaluronan matrix for cartilage repair

    Energy Technology Data Exchange (ETDEWEB)

    Nehrer, S. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.nehrer@meduniwien.ac.at; Domayer, S. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Dorotka, R. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Schatz, K. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Bindreiter, U. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Kotz, R. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2006-01-15

    Repair of articular cartilage represents a significant clinical problem and although various new techniques - including the use of autologous chondrocytes - have been developed within the last century the clinical efficacy of these procedures is still discussed controversially. Although autologous chondrocyte transplantation (ACT) has been widely used with success, it has several inherent limitations, including its invasive nature and problems related to the use of the periosteal flap. To overcome these problems autologous chondrocytes transplantation combined with the use of biodegradable scaffolds has received wide attention. Among these, a hyaluronan-based scaffold has been found useful for inducing hyaline cartilage regeneration. In the present study, we have investigated the mid-term efficacy and safety of Hyalograft[reg] C grafts in a group of 36 patients undergoing surgery for chronic cartilage lesions of the knee. Clinical Outcome was assessed prospectively before and at 12, 24, and 36 months after surgery. No major adverse events have been reported during the 3-year follow-up. Significant improvements of the evaluated scores were observed (P < 0.02) at 1 year and a continued increase of clinical performance was evident at 2 and 3 years follow-up. Patients under 30 years of age with single lesions showed statistically significant improvements at all follow-up visits compared to those over 30 with multiple defects (P < 0.01). Hyalograft[reg] C compares favorably with classic ACT and is particularly indicated in younger patients with single lesions. The graft can be implanted through a miniarthrotomy and needs no additional fixation with sutures except optional fibrin gluing at the defect borders. These results suggest that Hyalograft[reg] C is a valid alternative to ACT.

  16. Resurfacing Damaged Articular Cartilage to Restore Compressive Properties

    OpenAIRE

    Grenier, Stephanie; Donnelly, Patrick E; Gittens, Jamila; Torzilli, Peter A.

    2014-01-01

    Surface damage to articular cartilage is recognized as the initial underlying process causing the loss of mechanical function in early-stage osteoarthritis. In this study, we developed structure-modifying treatments to potentially prevent, stabilize or reverse the loss in mechanical function. Various polymers (chondroitin sulfate, carboxymethylcellulose, sodium hyaluronate) and photoinitiators (riboflavin, irgacure 2959) were applied to the surface of collagenase-degraded cartilage and crossl...

  17. Comparison of three types of chondrocytes in collagen scaffolds for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lu [Department of Plastic and Reconstructive Surgery, Shanghai Tissue Engineering Center, Shanghai 9th People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai (China); Spector, Myron, E-mail: luzhangmd@gmail.co [Tissue Engineering, VA Boston Healthcare System, Boston, MA (United States)

    2009-08-15

    The objective of this study was to compare the chondrogenesis in type I and II collagen scaffolds seeded with chondrocytes from three types of cartilage, after four weeks of culture: auricular (AU), articular (AR) and meniscal (ME). Related aims were to investigate the expression of a contractile muscle actin isoform, alpha-smooth muscle actin (SMA), in the cells in the scaffold and to determine the presence of a lubricating glycoprotein, lubricin, in the constructs. Adult goat AU, AR and ME chondrocytes were seeded into two types of collagen scaffolds: type II collagen and type I/III collagen. After four weeks of culture, the constructs were prepared for histochemical and immunohistochemical analysis of the distribution of glycosaminoglycan (GAG), types I and II collagen, elastin, SM and lubricin. AU constructs contained substantially more tissue than the AR and ME samples. The AU constructs exhibited neocartilage, but no elastin. There were no notable differences between the type I and II collagen scaffolds. Novel findings were the expression of SMA by the AU cells in the scaffolds and the presence of lubricin in the AR and AU constructs. AU cells have the capability to produce cartilage in collagen scaffolds under conditions in which there is little histogenesis by AR and ME cells.

  18. Modulation of Apoptosis and Differentiation by the Treatment of Sulfasalazine in Rabbit Articular Chondrocytes

    OpenAIRE

    Lee, Won Kil; Kang, Jin Seok

    2016-01-01

    This study was conducted to examine the cellular regulatory mechanisms of sulfasalazine (SSZ) in rabbit articular chondrocytes treated with sodium nitroprusside (SNP). Cell phenotype was determined, and the MTT assay, Western blot analysis and immunofluorescence staining of type II collagen was performed in control, SNP-treated and SNP plus SSZ (50~200 μg/mL) rabbit articular chondrocytes. Cellular proliferation was decreased significantly in the SNP-treated group compared with that in the co...

  19. Characterization of pediatric microtia cartilage: a reservoir of chondrocytes for auricular reconstruction using tissue engineering strategies.

    Science.gov (United States)

    Melgarejo-Ramírez, Y; Sánchez-Sánchez, R; García-López, J; Brena-Molina, A M; Gutiérrez-Gómez, C; Ibarra, C; Velasquillo, C

    2016-09-01

    The external ear is composed of elastic cartilage. Microtia is a congenital malformation of the external ear that involves a small reduction in size or a complete absence. The aim of tissue engineering is to regenerate tissues and organs clinically implantable based on the utilization of cells and biomaterials. Remnants from microtia represent a source of cells for auricular reconstruction using tissue engineering. To examine the macromolecular architecture of microtia cartilage and behavior of chondrocytes, in order to enrich the knowledge of this type of cartilage as a cell reservoir. Auricular cartilage remnants were obtained from pediatric patients with microtia undergoing reconstructive procedures. Extracellular matrix composition was characterized using immunofluorescence and histological staining methods. Chondrocytes were isolated and expanded in vitro using a mechanical-enzymatic protocol. Chondrocyte phenotype was analyzed using qualitative PCR. Microtia cartilage preserves structural organization similar to healthy elastic cartilage. Extracellular matrix is composed of typical cartilage proteins such as type II collagen, elastin and proteoglycans. Chondrocytes displayed morphological features similar to chondrocytes derived from healthy cartilage, expressing SOX9, COL2 and ELN, thus preserving chondral phenotype. Cell viability was 94.6 % during in vitro expansion. Elastic cartilage from microtia has similar characteristics, both architectural and biochemical to healthy cartilage. We confirmed the suitability of microtia remnant as a reservoir of chondrocytes with potential to be expanded in vitro, maintaining phenotypical features and viability. Microtia remnants are an accessible source of autologous cells for auricular reconstruction using tissue engineering strategies. PMID:27566509

  20. Strain-dependent oxidant release in articular cartilage originates from mitochondria.

    Science.gov (United States)

    Brouillette, M J; Ramakrishnan, P S; Wagner, V M; Sauter, E E; Journot, B J; McKinley, T O; Martin, J A

    2014-06-01

    Mechanical loading is essential for articular cartilage homeostasis and plays a central role in the cartilage pathology, yet the mechanotransduction processes that underlie these effects remain unclear. Previously, we showed that lethal amounts of reactive oxygen species (ROS) were liberated from the mitochondria in response to mechanical insult and that chondrocyte deformation may be a source of ROS. To this end, we hypothesized that mechanically induced mitochondrial ROS is related to the magnitude of cartilage deformation. To test this, we measured axial tissue strains in cartilage explants subjected to semi-confined compressive stresses of 0, 0.05, 0.1, 0.25, 0.5, or 1.0 MPa. The presence of ROS was then determined by confocal imaging with dihydroethidium, an oxidant sensitive fluorescent probe. Our results indicated that ROS levels increased linearly relative to the magnitude of axial strains (r(2) = 0.87, p 40%. By contrast, hydrostatic stress, which causes minimal tissue strain, had no significant effect. Cell-permeable superoxide dismutase mimetic Mn(III)tetrakis (1-methyl-4-pyridyl) porphyrin pentachloride significantly decreased ROS levels at 0.5 and 0.25 MPa. Electron transport chain inhibitor, rotenone, and cytoskeletal inhibitor, cytochalasin B, significantly decreased ROS levels at 0.25 MPa. Our findings strongly suggest that ROS and mitochondrial oxidants contribute to cartilage mechanobiology. PMID:23896937

  1. Culture of bovine articular chondrocytes in funnel-like collagen-PLGA hybrid sponges

    Energy Technology Data Exchange (ETDEWEB)

    Lu Hongxu; Ko, Young-Gwang; Kawazoe, Naoki; Chen Guoping, E-mail: Guoping.Chen@nims.go.jp [Tissue Regeneration Materials Unit, International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2011-08-15

    Three-dimensional porous scaffolds play an important role in tissue engineering and regenerative medicine. Structurally, these porous scaffolds should have an open and interconnected porous architecture to facilitate a homogeneous cell distribution. Moreover, the scaffolds should be mechanically strong to support new tissue formation. We developed a novel type of funnel-like collagen sponge using embossing ice particulates as a template. The funnel-like collagen sponges could promote the homogeneous cell distribution, ECM production and chondrogenesis. However, the funnel-like collagen sponges deformed during cell culture due to their weak mechanical strength. To solve this problem, we reinforced the funnel-like collagen sponges with a knitted poly(D,L-lactic-co-glycolic acid) (PLGA) mesh by hybridizing these two types of materials. The hybrid scaffolds were used to culture bovine articular chondrocytes. The cell adhesion, distribution, proliferation and chondrogenesis were investigated. The funnel-like structure promoted the even cell distribution and homogeneous ECM production. The PLGA knitted mesh protected the scaffold from deformation during cell culture. Histological and immunohistochemical staining and cartilaginous gene expression analyses revealed the cartilage-like properties of the cell/scaffold constructs after in vivo implantation. The hybrid scaffold, composed of a funnel-like collagen sponge and PLGA mesh, would be a useful tool for cartilage tissue engineering.

  2. A Validated Model of the Pro- and Anti-inflammatory Cytokine Balancing Act in Articular Cartilage Lesion Formation

    Directory of Open Access Journals (Sweden)

    Xiayi eWang

    2015-03-01

    Full Text Available Traumatic injuries of articular cartilage result in the formation of a cartilage lesion and contribute to cartilage degeneration and the risk of osteoarthritis (OA. A better understanding of the framework for the formation of a cartilage lesion formation would be helpful in therapy development. Towards this end, we present an age and space-structured model of articular cartilage lesion formation after a single blunt impact. This model modifies the reaction-diffusion-delay models in Graham et al. (2012 (single impact and Wang et al. (2014 (cyclic loading, focusing on the balancing act' between pro- and anti-inflammatory cytokines. Age structure is introduced to replace the delay terms for cell transitions used in these earlier models; we find age structured models to be more flexible in representing the underlying biological system and more tractable computationally. Numerical results show a successful capture of chondrocyte behavior and chemical activities associated with the cartilage lesion after the initial injury; experimental validation of our computational results is presented. We anticipate that our in silico model of cartilage damage from a single blunt impact can be used to provide information that may not be easily obtained through in in vivo or in vitro studies.

  3. A validated model of the pro- and anti-inflammatory cytokine balancing act in articular cartilage lesion formation.

    Science.gov (United States)

    Wang, Xiayi; Brouillette, Marc J; Ayati, Bruce P; Martin, James A

    2015-01-01

    Traumatic injuries of articular cartilage result in the formation of a cartilage lesion and contribute to cartilage degeneration and the risk of osteoarthritis (OA). A better understanding of the framework for the formation of a cartilage lesion formation would be helpful in therapy development. Toward this end, we present an age and space-structured model of articular cartilage lesion formation after a single blunt impact. This model modifies the reaction-diffusion-delay models in Graham et al. (2012) (single impact) and Wang et al. (2014) (cyclic loading), focusing on the "balancing act" between pro- and anti-inflammatory cytokines. Age structure is introduced to replace the delay terms for cell transitions used in these earlier models; we find age structured models to be more flexible in representing the underlying biological system and more tractable computationally. Numerical results show a successful capture of chondrocyte behavior and chemical activities associated with the cartilage lesion after the initial injury; experimental validation of our computational results is presented. We anticipate that our in silico model of cartilage damage from a single blunt impact can be used to provide information that may not be easily obtained through in in vivo or in vitro studies. PMID:25806365

  4. Wnt/β-catenin signaling of cartilage canal and osteochondral junction chondrocytes and full thickness cartilage in early equine osteochondrosis.

    Science.gov (United States)

    Kinsley, Marc A; Semevolos, Stacy A; Duesterdieck-Zellmer, Katja F

    2015-10-01

    The objective of this study was to elucidate gene and protein expression of Wnt signaling molecules in chondrocytes of foals having early osteochondrosis (OC) versus normal controls. The hypothesis was that increased expression of components of Wnt signaling pathway in osteochondral junction (OCJ) and cartilage canal (CC) chondrocytes would be found in early OC when compared to controls. Paraffin-embedded osteochondral samples (7 OC, 8 normal) and cDNA from whole cartilage (7 OC, 10 normal) and chondrocytes surrounding cartilage canals and osteochondral junctions captured with laser capture microdissection (4 OC, 6 normal) were obtained from femoropatellar joints of 17 immature horses. Equine-specific Wnt signaling molecule mRNA expression levels were evaluated by two-step real-time qPCR. Spatial tissue protein expression of β-catenin, Wnt-11, Wnt-4, and Dkk-1 was determined by immunohistochemistry. There was significantly decreased Wnt-11 and increased β-catenin, Wnt-5b, Dkk-1, Lrp6, Wif-1, Axin1, and SC-PEP gene expression in early OC cartilage canal chondrocytes compared to controls. There was also significantly increased β-catenin gene expression in early OC osteochondral junction chondrocytes compared to controls. Based on this study, abundant gene expression differences in OC chondrocytes surrounding cartilage canals suggest pathways associated with catabolism and inhibition of chondrocyte maturation are targeted in early OC pathogenesis. PMID:25676127

  5. Nanocomposite scaffold for chondrocyte growth and cartilage tissue engineering: effects of carbon nanotube surface functionalization.

    Science.gov (United States)

    Chahine, Nadeen O; Collette, Nicole M; Thomas, Cynthia B; Genetos, Damian C; Loots, Gabriela G

    2014-09-01

    The goal of this study was to assess the long-term biocompatibility of single-wall carbon nanotubes (SWNTs) for tissue engineering of articular cartilage. We hypothesized that SWNT nanocomposite scaffolds in cartilage tissue engineering can provide an improved molecular-sized substrate for stimulation of chondrocyte growth, as well as structural reinforcement of the scaffold's mechanical properties. The effect of SWNT surface functionalization (-COOH or -PEG) on chondrocyte viability and biochemical matrix deposition was examined in two-dimensional cultures, in three-dimensional (3D) pellet cultures, and in a 3D nanocomposite scaffold consisting of hydrogels+SWNTs. Outcome measures included cell viability, histological and SEM evaluation, GAG biochemical content, compressive and tensile biomechanical properties, and gene expression quantification, including extracellular matrix (ECM) markers aggrecan (Agc), collagen-1 (Col1a1), collagen-2 (Col2a1), collagen-10 (Col10a1), surface adhesion proteins fibronectin (Fn), CD44 antigen (CD44), and tumor marker (Tp53). Our findings indicate that chondrocytes tolerate functionalized SWNTs well, with minimal toxicity of cells in 3D culture systems (pellet and nanocomposite constructs). Both SWNT-PEG and SWNT-COOH groups increased the GAG content in nanocomposites relative to control. The compressive biomechanical properties of cell-laden SWNT-COOH nanocomposites were significantly elevated relative to control. Increases in the tensile modulus and ultimate stress were observed, indicative of a tensile reinforcement of the nanocomposite scaffolds. Surface coating of SWNTs with -COOH also resulted in increased Col2a1 and Fn gene expression throughout the culture in nanocomposite constructs, indicative of increased chondrocyte metabolic activity. In contrast, surface coating of SWNTs with a neutral -PEG moiety had no significant effect on Col2a1 or Fn gene expression, suggesting that the charged nature of the -COOH surface

  6. Suppression of glycosaminoglycan synthesis by articular cartilage, but not of hyaluronic acid synthesis by synovium, after exposure to radiation

    International Nuclear Information System (INIS)

    We recently found that injection of 2 mCi of yttrium 90 (90Y; approximately 23,000 rads) into normal canine knees stimulated glycosaminoglycan (GAG) synthesis by femoral condylar cartilage. The present investigation was conducted to determine whether radiation affects cartilage metabolism directly. Rates of GAG synthesis and degradation in normal canine articular cartilage were studied following irradiation. Cultured synovium from the same knees was treated similarly, to determine the effects of irradiation on hyaluronic acid synthesis. Twenty-four hours after exposure to 1,000 rads, 10,000 rads, or 50,000 rads, 35S-GAG synthesis by the cartilage was 93%, 69%, and 37%, respectively, of that in control, nonirradiated cartilage. The effect was not rapidly reversible: 120 hours after exposure to 50,000 rads, GAG synthesis remained at only 28% of the control level. Autoradiography showed marked suppression of 35S uptake by chondrocytes after irradiation. Cartilage GAG degradation was also increased following irradiation: 4 hours and 8 hours after exposure to 50,000 rads, the cartilage GAG concentration was only 66% and 54%, respectively, of that at time 0, while corresponding values for control, nonirradiated cartilage were 90% and 87%. In contrast to its effects on cartilage GAG metabolism, radiation at these levels had no effect on synovial hyaluronic acid synthesis

  7. Suppression of glycosaminoglycan synthesis by articular cartilage, but not of hyaluronic acid synthesis by synovium, after exposure to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hugenberg, S.T.; Myers, S.L.; Brandt, K.D.

    1989-04-01

    We recently found that injection of 2 mCi of yttrium 90 (90Y; approximately 23,000 rads) into normal canine knees stimulated glycosaminoglycan (GAG) synthesis by femoral condylar cartilage. The present investigation was conducted to determine whether radiation affects cartilage metabolism directly. Rates of GAG synthesis and degradation in normal canine articular cartilage were studied following irradiation. Cultured synovium from the same knees was treated similarly, to determine the effects of irradiation on hyaluronic acid synthesis. Twenty-four hours after exposure to 1,000 rads, 10,000 rads, or 50,000 rads, 35S-GAG synthesis by the cartilage was 93%, 69%, and 37%, respectively, of that in control, nonirradiated cartilage. The effect was not rapidly reversible: 120 hours after exposure to 50,000 rads, GAG synthesis remained at only 28% of the control level. Autoradiography showed marked suppression of 35S uptake by chondrocytes after irradiation. Cartilage GAG degradation was also increased following irradiation: 4 hours and 8 hours after exposure to 50,000 rads, the cartilage GAG concentration was only 66% and 54%, respectively, of that at time 0, while corresponding values for control, nonirradiated cartilage were 90% and 87%. In contrast to its effects on cartilage GAG metabolism, radiation at these levels had no effect on synovial hyaluronic acid synthesis.

  8. THE FUNCTIONAL EFFECTIVENESS OF A CELL-ENGINEERED CONSTRUCT FOR THE REGENERATION OF ARTICULAR CARTILAGE

    Directory of Open Access Journals (Sweden)

    V. I. Sevastianov

    2015-04-01

    Full Text Available The aim of this study is an analysis of the functional effectiveness of a biomedical cell product consisting of a biopolymer microheterogeneous collagen-containing hydrogel (BMCH, human adipose-derived mesenchymal stromal cells (hADMSCs, and chondrogenic induction medium in the regeneration of articular cartilage. Materials and methods. The test model of the adjuvant arthritis was used (female Soviet Chinchilla rabbits with the further development into osteoarthrosis (OA combined with the clinical, biochemical, radiological, and histochemical trials. Results. On Day 92 of the OA model it has been found that the intra-articular introduction of a BMCH with hADMSCs into the left knee joint (n = 3 30 days after the OA modeling, as opposed to the right joint (negative control, n = 3, stimulates the regenerative processes of the cartilaginous tissue structure characterized by the formation of chondrocyte «columns», the emergence of isogenic groups in the intracellular matrix and the regeneration of its structure. Upon the intra-articular introduction of a BMCH (n = 3 such effects are markedly less pronounced. Conclusions. A significant regenerative potential of a cell-engineered construct of human articular tissue (CEC ATh has been proven. It is possible to presume that biostimulating properties of CEC ATh are due to the activating effect of a biomedical cell product on the stem cell migration processes from the surrounding tissue into the injured area with their subsequent differentiation. 

  9. Simvastatin induces differentiation of rabbit articular chondrocytes via the ERK-1/2 and p38 kinase pathways.

    Science.gov (United States)

    Han, Yohan; Kim, Song Ja

    2016-08-15

    Statins are competitive inhibitors of hydroxy-methyl-glutaryl Coenzyme A (HMG-CoA) reductase, a key enzyme involved in the conversion of HMG-CoA to the cholesterol precursor mevalonate. Some statins, such as simvastatin (simvastatin), have been shown to have anti-cancer and anti-inflammatory effects, reducing cartilage degradation in osteoarthritic rabbits in vivo. However, the regulatory mechanisms undergirding simvastatin mediated chondrocyte differentiation have not been well elucidated. Thus, we investigated the action and mechanism of simvastatin on differentiation of rabbit articular chondrocytes through western blot analyses, RT-PCR, and immunohistochemical (IHC) and immunofluorescence (IF) staining. Simvastatin treatment was found to induce type II collagen expression and sulfated-proteoglycan synthesis in a dose- and time-dependent manner. Indeed, RT-PCR revealed increased expression of type II collagen on treatment with simvastatin. Both IHC and IF staining indicated differentiation of chondrocytes. Simvastatin treatment reduced activation of ERK-1/2 and stimulated activation of p38 kinase. Inhibition of ERK-1/2 with PD98059 enhanced simvastatin induced differentiation, whereas inhibition of p38 kinase with SB203580 inhibited simvastatin induced differentiation. Simvastatin treatment also inhibits loss of type II collagen in serial monolayer culture. Collectively, our results indicate that ERK-1/2 and p38 kinase regulate simvastatin-induced differentiation of chondrocytes in opposing manners. Thus, these findings suggest that simvastatin may be a potential therapeutic drug for osteoarthritis. PMID:27475840

  10. Different hyaluronic acid morphology modulates primary articular chondrocyte behavior in hyaluronic acid-coated polycaprolactone scaffolds

    OpenAIRE

    Lebourg, Myriam; Rodenas Rochina, Joaquín; Sousa, Tiago; Mano, J. F.; Gómez Ribelles, J. L.

    2013-01-01

    Scaffolds for cartilage tissue engineering should promote both adequate biomechanical environment and chondrogenic stimulation. Hyaluronic acid (HA) has been used in cartilage engineering for its chondrogenic and chondroprotective properties, nevertheless its mechanical properties are limited. Influence of HA microstructure in chondrocyte response has not been addressed yet. In this work, polycaprolactone (PCL) scaffolds were modified using HA following two coating str...

  11. Spatially resolved elemental distributions in articular cartilage

    International Nuclear Information System (INIS)

    In this study, the nuclear microprobe technique is employed to analyse the chemistry of joint cartilage in order to correlate internal structures of the collagen network with the elemental distribution. The samples were taken from pig's knee joint. 30 μm thick coronar cross-sections were prepared by means of cryosectioning and freeze-drying. We performed simultaneously particle induced X-ray emission (PIXE), Rutherford backscattering spectrometry (RBS) and elastic recoil detection analysis (ERDA). Thus we obtained spatially resolved distributions of the elements H, C, N, O, P, S, Cl, K and Ca. The main components of the organic matrix are H, C, N and O. It was shown that their relations vary with the cartilage structures. It could be shown that zones with aligned collagen fibrils contain less sulphur and potassium but more chlorine. The higher chlorine concentration is remarkable because newest biochemical studies found that hypochloric acid is involved in cartilage degradation. Furthermore, the calcium distribution is still of great interest. Its correlation to structural changes inside the cartilage is still being discussed. It could be disproved that zones of higher calcium concentration are related to the aligned structures of the collagen network

  12. A suppressive effect of prostaglandin E2 on the expression of SERPINE1/plasminogen activator inhibitor-1 in human articular chondrocytes: An in vitro pilot study

    Directory of Open Access Journals (Sweden)

    Kayo Masuko

    2009-04-01

    Full Text Available Kayo Masuko1, Minako Murata2, Naoya Suematsu1, Kazuki Okamoto1, Kazuo Yudoh2, Hiroyuki Shimizu3, Moroe Beppu3, Hiroshi Nakamura4, Tomohiro Kato11Department of Biochemistry; 2Department of Frontier Medicine, Institute of Medical Science; 3Department of Orthopedic Surgery, St. Marianna University School of Medicine, Kawasaki-shi, Kanagawa, Japan; 4Department of Joint Disease and Rheumatism, Nippon Medical School, Bunkyo-ku, Tokyo, JapanAbstract: Prostaglandin E2 (PGE2 is expressed in articular joints with inflammatory arthropathy and may exert catabolic effects leading to cartilage degradation. As we observed in a preliminary experiment that PGE2 suppressed the expression of SERPINE1/plasminogen activator inhibitor (PAI-1 mRNA in chondrocytes, we focused on the effect of PGE2 on PAI-1 in a panel of cultured chondrocytes obtained from osteoarthritic patients. Specifically, articular cartilage specimens were obtained from patients with osteoarthritis who underwent joint surgery. Isolated chondrocytes were cultured in vitro as a monolayer and stimulated with PGE2. Stimulated cells and culture supernatants were analyzed using Western blotting and enzyme-linked immunosorbent assay. The results confirmed that the in vitro PGE2 stimulation suppressed the expression of PAI-1 in the tested chondrocyte samples. The inhibitory effect was partly abrogated by an antagonist of EP4 receptor of PGE2, but not by an EP2 antagonist. Although PGE2 induced activations of mitogen-activated protein kinases (MAPK, blocking of the MAPK did not abrogate the suppressive effect of PGE2, implying a distinct signaling pathway. In summary, prostaglandin is suggested to modulate the plasminogen system in chondrocytes. Further elucidation of the interaction might open a new avenue to understand the degradative process of cartilage.Keywords: chondrocyte, prostaglandin, PGE2, PAI-1

  13. Modulation of Apoptosis and Differentiation by the Treatment of Sulfasalazine in Rabbit Articular Chondrocytes

    Science.gov (United States)

    Lee, Won Kil; Kang, Jin Seok

    2016-01-01

    This study was conducted to examine the cellular regulatory mechanisms of sulfasalazine (SSZ) in rabbit articular chondrocytes treated with sodium nitroprusside (SNP). Cell phenotype was determined, and the MTT assay, Western blot analysis and immunofluorescence staining of type II collagen was performed in control, SNP-treated and SNP plus SSZ (50~200 μg/mL) rabbit articular chondrocytes. Cellular proliferation was decreased significantly in the SNP-treated group compared with that in the control (p < 0.01). SSZ treatment clearly increased the SNP-reduced proliferation levels in a concentration-dependent manner (p < 0.01). SNP treatment induced significant dedifferentiation and inflammation compared with control chondrocytes (p < 0.01). Type II collagen expression levels increased in a concentration-dependent manner in response to SSZ treatment but were unaltered in SNP-treated chondrocytes (p < 0.05 and < 0.01, respectively). Cylooxygenase-2 (COX-2) expression increased in a concentration-dependent manner in response to SSZ treatment but was unaltered in SNP-treated chondrocytes (p < 0.05). Immunofluorescence staining showed that SSZ treatment increased type II collagen expression compared with that in SNP-treated chondrocytes. Furthermore, phosphorylated extracellular regulated kinase (pERK) expression levels were decreased significantly in the SNP-treated group compared with those in control chondrocytes (p < 0.01). Expression levels of pERK increased in a concentration-dependent manner by SSZ but were unaltered in SNP-treated chondrocytes. pp38 kinase expression levels increased in a concentration-dependent manner by SSZ but were unaltered in control chondrocytes (p < 0.01). In summary, SSZ significantly inhibited nitric oxide-induced cell death and dedifferentiation, and regulated extracellular regulated kinases 1 and 2 and p38 kinase in rabbit articular chondrocytes. PMID:27123162

  14. Nanomechanical phenotype of chondroadherin-null murine articular cartilage.

    Science.gov (United States)

    Batista, Michael A; Nia, Hadi T; Önnerfjord, Patrik; Cox, Karen A; Ortiz, Christine; Grodzinsky, Alan J; Heinegård, Dick; Han, Lin

    2014-09-01

    Chondroadherin (CHAD), a class IV small leucine rich proteoglycan/protein (SLRP), was hypothesized to play important roles in regulating chondrocyte signaling and cartilage homeostasis. However, its roles in cartilage development and function are not well understood, and no major osteoarthritis-like phenotype was found in the murine model with CHAD genetically deleted (CHAD(-/-)). In this study, we used atomic force microscopy (AFM)-based nanoindentation to quantify the effects of CHAD deletion on changes in the biomechanical function of murine cartilage. In comparison to wild-type (WT) mice, CHAD-deletion resulted in a significant ≈70-80% reduction in the indentation modulus, Eind, of the superficial zone knee cartilage of 11 weeks, 4 months and 1 year old animals. This mechanical phenotype correlates well with observed increases in the heterogeneity collagen fibril diameters in the surface zone. The results suggest that CHAD mainly plays a major role in regulating the formation of the collagen fibrillar network during the early skeletal development. In contrast, CHAD-deletion had no appreciable effects on the indentation mechanics of middle/deep zone cartilage, likely due to the dominating role of aggrecan in the middle/deep zone. The presence of significant rate dependence of the indentation stiffness in both WT and CHAD(-/-) knee cartilage suggested the importance of both fluid flow induced poroelasticity and intrinsic viscoelasticity in murine cartilage biomechanical properties. Furthermore, the marked differences in the nanomechanical behavior of WT versus CHAD(-/-) cartilage contrasted sharply with the relative absence of overt differences in histological appearance. These observations highlight the sensitivity of nanomechanical tools in evaluating structural and mechanical phenotypes in transgenic mice. PMID:24892719

  15. Role of Insulin-Transferrin-Selenium in Auricular Chondrocyte Proliferation and Engineered Cartilage Formation in Vitro

    Directory of Open Access Journals (Sweden)

    Xia Liu

    2014-01-01

    Full Text Available The goal of this study is to determine the effects of Insulin-Transferrin-Selenium (ITS on proliferation of auricular chondrocytes and formation of engineered cartilage in vitro. Pig auricular monolayer chondrocytes and chondrocyte pellets were cultured in media containing 1% ITS at different concentrations of fetal bovine serum (FBS, 10%, 6%, 2%, 0%, or 10% FBS alone as a control for four weeks. Parameters including cell proliferation in monolayer, wet weight, collagen type I/II/X (Col I, II, X and glycosaminoglycan (GAG expression, GAG content of pellets and gene expression associated with cartilage formation/dedifferentiation (lost cartilage phenotype/hypertrophy within the chondrocyte pellets were assessed. The results showed that chondrocytes proliferation rates increased when FBS concentrations increased (2%, 6%, 10% FBS in ITS supplemented groups. In addition, 1% ITS plus 10% FBS significantly promoted cell proliferation than 10% FBS alone. No chondrocytes grew in ITS alone medium. 1% ITS plus 10% FBS enhanced cartilage formation in terms of size, wet weight, cartilage specific matrices, and homogeneity, compared to 10% FBS alone group. Furthermore, ITS prevented engineered cartilage from dedifferentiation (i.e., higher index of Col II/Col I mRNA expression and expression of aggrecan and hypertrophy (i.e., lower mRNA expression of Col X and MMP13. In conclusion, our results indicated that ITS efficiently enhanced auricular chondrocytes proliferation, retained chondrogenic phenotypes, and promoted engineered cartilage formation when combined with FBS, which is potentially used as key supplementation in auricular chondrocytes and engineered cartilage culture.

  16. Protocols for the in vitro design of animal articular cartilage based on tissue engineering methods

    Directory of Open Access Journals (Sweden)

    Diego Correa

    2012-10-01

    Full Text Available The articular cartilage is the structure that covers the joint ends. It has some specific tasks crucial to the correct joint physiology. It may experience a large amount of injuries that could generate considerable disabilities. Unfortunately its selfrepair capacity is too limited; therefore, many treatments have been developed with partial success, given the suboptimal biomechanical behavior of the resultant tissue. Given that, Tissue Engineering offers an alternative, based on the design of a new tissue with biological and biomechanical features which resembles the native tissue. In this work, the authors describe the methodologies followed to accomplish that goal, studying the chondrocytes harvesting, the cellular cultures, the scaffold seeding processes, the mechanical stimulation and the structural and biomechanical evaluation. Finally, exposed some of the preliminary results, as a experimental validation of the methods proposed are.

  17. Analysis of friction between articular cartilage and polyvinyl alcohol hydrogel artificial cartilage.

    Science.gov (United States)

    Li, Feng; Wang, Anmin; Wang, Chengtao

    2016-05-01

    Many biomaterials are being used to repair damaged articular cartilage. In particular, poly vinyl alcohol hydrogel has similar mechanical properties to natural cartilage under compressive and shearing loading. Here, three-factor and two-level friction experiments and long-term tests were conducted to better evaluate its tribological properties. The friction coefficient between articular cartilage and the poly vinyl alcohol hydrogel depended primarily on the three factors of load, speed, and lubrication. When the speed increased from 10 to 20 mm/s under a load of 10 N, the friction coefficient increased from 0.12 to 0.147. When the lubricant was changed from Ringer's solution to a hyaluronic acid solution, the friction coefficient decreased to 0.084 with loads as high as 22 N. The poly vinyl alcohol hydrogel was severely damaged and lost its top surface layers, which were transferred to the articular cartilage surface. Wear was observed in the surface morphologies, which indicated the occurrence of surface adhesion of bovine cartilage. Surface fatigue and adhesive wear was the dominant wear mechanism. PMID:26970769

  18. The evolution of articular cartilage imaging and its impact on clinical practice

    International Nuclear Information System (INIS)

    Over the past four decades, articular cartilage imaging has developed rapidly. Imaging now plays a critical role not only in clinical practice and therapeutic decisions but also in the basic research probing our understanding of cartilage physiology and biomechanics. (orig.)

  19. Use of micro-computed tomography to evaluate the effects of exercise on preventing the degeneration of articular cartilage in tail-suspended rats

    Science.gov (United States)

    Luan, Hui-Qin; Sun, Lian-Wen; Huang, Yun-Fei; Wu, Xin-tong; Niu, Haijun; Liu, Hong; Fan, Yu-Bo

    2015-07-01

    Space flight has been shown to induce bone loss and muscle atrophy, which could initiate the degeneration of articular cartilage. Countermeasures to prevent bone loss and muscle atrophy have been explored, but few spaceflight or ground-based studies have focused on the effects on cartilage degeneration. In this study, we investigated the effects of exercise on articular cartilage deterioration in tail-suspended rats. Thirty-two female Sprague-Dawley rats were randomly divided into four groups (n = 8 in each): tail suspension (TS), tail suspension plus passive motion (TSP), tail suspension plus active exercise (TSA), and control (CON) groups. In the TS, TSP, and TSA groups, the rat hindlimbs were unloaded for 21 days by tail suspension. Next, the cartilage thickness and volume, and the attenuation coefficient of the distal femur were evaluated by micro-computed tomography (μCT). Histological analysis was used to assess the surface integrity of the cartilage, cartilage thickness, and chondrocytes. The results showed that: (1) the cartilage thickness on the distal femur was significantly lower in the TS and TSP groups compared with the CON and TSA groups; (2) the cartilage volume in the TS group was significantly lower compared with the CON, TSA, and TSP groups; and (3) histomorphology showed that the chondrocytes formed clusters where the degree of matrix staining was lower in the TS and TSP groups. There were no significant differences between any of these parameters in the CON and TSA groups. The cartilage thickness measurements obtained by μCT and histomorphology correlated well. In general, tail suspension could induce articular cartilage degeneration, but active exercise was effective in preventing this degeneration in tail-suspended rats.

  20. Zn deposition at the bone cartilage interface in equine articular cartilage

    Science.gov (United States)

    Bradley, D. A.; Moger, C. J.; Winlove, C. P.

    2007-09-01

    In articular cartilage metalloproteinases, a family of enzymes whose function relies on the presence of divalent cations such as Zn and Ca plays a central role in the normal processes of growth and remodelling and in the degenerative and inflammatory processes of arthritis. Another important enzyme, alkaline phosphatase, involved in cartilage mineralisation also relies on metallic cofactors. The local concentration of divalent cations is therefore of considerable interest in cartilage pathophysiology and several authors have used synchrotron X-ray fluorescence (XRF) to map metal ion distributions in bone and cartilage. We report use of a bench-top XRF analytical microscope, providing spatial resolution of 10 μm and applicable to histological sections, facilitating correlation of the distribution with structural features. The study seeks to establish the elemental distribution in normal tissue as a precursor to investigation of changes in disease. For six samples prepared from equine metacarpophalangeal joint, we observed increased concentration of Zn and Sr ions around the tidemark between normal and mineralised cartilage. This is believed to be an active site of remodelling but its composition has hitherto lacked detailed characterization. We also report preliminary results on two of the samples using Proton-Induced X-ray Emission (PIXE). This confirms our previous observations using synchrotron-based XRF of enhanced deposition of Sr and Zn at the surface of the subchondral bone and in articular cartilage.

  1. Zn deposition at the bone-cartilage interface in equine articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.A. [Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom)], E-mail: D.A.Bradley@surrey.ac.uk; Moger, C.J.; Winlove, C.P. [School of Physics, University of Exeter, Exeter, EX4 4QL (United Kingdom)

    2007-09-21

    In articular cartilage metalloproteinases, a family of enzymes whose function relies on the presence of divalent cations such as Zn and Ca plays a central role in the normal processes of growth and remodelling and in the degenerative and inflammatory processes of arthritis. Another important enzyme, alkaline phosphatase, involved in cartilage mineralisation also relies on metallic cofactors. The local concentration of divalent cations is therefore of considerable interest in cartilage pathophysiology and several authors have used synchrotron X-ray fluorescence (XRF) to map metal ion distributions in bone and cartilage. We report use of a bench-top XRF analytical microscope, providing spatial resolution of 10 {mu}m and applicable to histological sections, facilitating correlation of the distribution with structural features. The study seeks to establish the elemental distribution in normal tissue as a precursor to investigation of changes in disease. For six samples prepared from equine metacarpophalangeal joint, we observed increased concentration of Zn and Sr ions around the tidemark between normal and mineralised cartilage. This is believed to be an active site of remodelling but its composition has hitherto lacked detailed characterization. We also report preliminary results on two of the samples using Proton-Induced X-ray Emission (PIXE). This confirms our previous observations using synchrotron-based XRF of enhanced deposition of Sr and Zn at the surface of the subchondral bone and in articular cartilage.

  2. Zn deposition at the bone-cartilage interface in equine articular cartilage

    International Nuclear Information System (INIS)

    In articular cartilage metalloproteinases, a family of enzymes whose function relies on the presence of divalent cations such as Zn and Ca plays a central role in the normal processes of growth and remodelling and in the degenerative and inflammatory processes of arthritis. Another important enzyme, alkaline phosphatase, involved in cartilage mineralisation also relies on metallic cofactors. The local concentration of divalent cations is therefore of considerable interest in cartilage pathophysiology and several authors have used synchrotron X-ray fluorescence (XRF) to map metal ion distributions in bone and cartilage. We report use of a bench-top XRF analytical microscope, providing spatial resolution of 10 μm and applicable to histological sections, facilitating correlation of the distribution with structural features. The study seeks to establish the elemental distribution in normal tissue as a precursor to investigation of changes in disease. For six samples prepared from equine metacarpophalangeal joint, we observed increased concentration of Zn and Sr ions around the tidemark between normal and mineralised cartilage. This is believed to be an active site of remodelling but its composition has hitherto lacked detailed characterization. We also report preliminary results on two of the samples using Proton-Induced X-ray Emission (PIXE). This confirms our previous observations using synchrotron-based XRF of enhanced deposition of Sr and Zn at the surface of the subchondral bone and in articular cartilage

  3. Mechanical stress and ATP synthesis are coupled by mitochondrial oxidants in articular cartilage.

    Science.gov (United States)

    Wolff, Katherine J; Ramakrishnan, Prem S; Brouillette, Marc J; Journot, Brice J; McKinley, Todd O; Buckwalter, Joseph A; Martin, James A

    2013-02-01

    Metabolic adaptation of articular cartilage under joint loading is evident and matrix synthesis seems to be critically tied to ATP. Chondrocytes utilize the glycolytic pathway for energy requirements but seem to require mitochondrial reactive oxygen species (ROS) to sustain ATP synthesis. The role of ROS in regulating ATP reserves under a mechanically active environment is not clear. It is believed that physiological strains cause deformation of the mitochondria, potentially releasing ROS for energy production. We hypothesized that mechanical loading stimulates ATP synthesis via mitochondrial release of ROS. Bovine osteochondral explants were dynamically loaded at 0.5 Hz with amplitude of 0.25 MPa for 1 h. Cartilage response to mechanical loading was assessed by imaging with dihydroethidium (ROS indicator) and a Luciferase-based ATP assay. Electron transport inhibitor rotenone and mitochondrial ROS scavenger MitoQ significantly suppressed mechanically induced ROS production and ATP synthesis. Our findings indicate that mitochondrial ROS are produced as a result of physiological mechanical strains. Taken together with our previous findings of ROS involvement in blunt impact injuries, mitochondrial ROS are important contributors to cartilage metabolic adaptation and their precise role in the pathogenesis of osteoarthritis warrants further investigation. PMID:22930474

  4. Melanocortin 1 receptor-signaling deficiency results in an articular cartilage phenotype and accelerates pathogenesis of surgically induced murine osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Julia Lorenz

    Full Text Available Proopiomelanocortin-derived peptides exert pleiotropic effects via binding to melanocortin receptors (MCR. MCR-subtypes have been detected in cartilage and bone and mediate an increasing number of effects in diathrodial joints. This study aims to determine the role of MC1-receptors (MC1 in joint physiology and pathogenesis of osteoarthritis (OA using MC1-signaling deficient mice (Mc1re/e. OA was surgically induced in Mc1re/e and wild-type (WT mice by transection of the medial meniscotibial ligament. Histomorphometry of Safranin O stained articular cartilage was performed with non-operated controls (11 weeks and 6 months and 4/8 weeks past surgery. µCT-analysis for assessing epiphyseal bone architecture was performed as a longitudinal study at 4/8 weeks after OA-induction. Collagen II, ICAM-1 and MC1 expression was analysed by immunohistochemistry. Mc1re/e mice display less Safranin O and collagen II stained articular cartilage area compared to WT prior to OA-induction without signs of spontaneous cartilage surface erosion. This MC1-signaling deficiency related cartilage phenotype persisted in 6 month animals. At 4/8 weeks after OA-induction cartilage erosions were increased in Mc1re/e knees paralleled by weaker collagen II staining. Prior to OA-induction, Mc1re/e mice do not differ from WT with respect to bone parameters. During OA, Mc1re/e mice developed more osteophytes and had higher epiphyseal bone density and mass. Trabecular thickness was increased while concomitantly trabecular separation was decreased in Mc1re/e mice. Numbers of ICAM-positive chondrocytes were equal in non-operated 11 weeks Mc1re/e and WT whereas number of positive chondrocytes decreased during OA-progression. Unchallenged Mc1re/e mice display smaller articular cartilage covered area without OA-related surface erosions indicating that MC1-signaling is critical for proper cartilage matrix integrity and formation. When challenged with OA, Mc1re/e mice develop a more

  5. T2 star relaxation times for assessment of articular cartilage at 3 T: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Mamisch, Tallal Charles [University Bern, Department of Orthopedic Surgery, Inselspital, Bern (Switzerland); University Bern, Magnetic Resonance Spectroscopy and Methodology, Department of Clinical Research, Bern (Switzerland); Hughes, Timothy [Siemens Medical Solutions, Erlangen (Germany); Mosher, Timothy J. [Penn State University College of Medicine, Musculoskeletal Imaging and MRI, Department of Radiology, Hershey, PA (United States); Mueller, Christoph [University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Trattnig, Siegfried [Medical University of Vienna, MR Center - High Field MR, Department of Radiology, Vienna (Austria); Boesch, Chris [University Bern, Magnetic Resonance Spectroscopy and Methodology, Department of Clinical Research, Bern (Switzerland); Welsch, Goetz Hannes [University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Medical University of Vienna, MR Center - High Field MR, Department of Radiology, Vienna (Austria)

    2012-03-15

    T2 mapping techniques use the relaxation constant as an indirect marker of cartilage structure, and the relaxation constant has also been shown to be a sensitive parameter for cartilage evaluation. As a possible additional robust biomarker, T2* relaxation time is a potential, clinically feasible parameter for the biochemical evaluation of articular cartilage. The knees of 15 healthy volunteers and 15 patients after microfracture therapy (MFX) were evaluated with a multi-echo spin-echo T2 mapping technique and a multi-echo gradient-echo T2* mapping sequence at 3.0 Tesla MRI. Inline maps, using a log-linear least squares fitting method, were assessed with respect to the zonal dependency of T2 and T2* relaxation for the deep and superficial regions of healthy articular cartilage and cartilage repair tissue. There was a statistically significant correlation between T2 and T2* values. Both parameters demonstrated similar spatial dependency, with longer values measured toward the articular surface for healthy articular cartilage. No spatial variation was observed for cartilage repair tissue after MFX. Within this feasibility study, both T2 and T2* relaxation parameters demonstrated a similar response in the assessment of articular cartilage and cartilage repair tissue. The potential advantages of T2*-mapping of cartilage include faster imaging times and the opportunity for 3D acquisitions, thereby providing greater spatial resolution and complete coverage of the articular surface. (orig.)

  6. T2 star relaxation times for assessment of articular cartilage at 3 T: a feasibility study

    International Nuclear Information System (INIS)

    T2 mapping techniques use the relaxation constant as an indirect marker of cartilage structure, and the relaxation constant has also been shown to be a sensitive parameter for cartilage evaluation. As a possible additional robust biomarker, T2* relaxation time is a potential, clinically feasible parameter for the biochemical evaluation of articular cartilage. The knees of 15 healthy volunteers and 15 patients after microfracture therapy (MFX) were evaluated with a multi-echo spin-echo T2 mapping technique and a multi-echo gradient-echo T2* mapping sequence at 3.0 Tesla MRI. Inline maps, using a log-linear least squares fitting method, were assessed with respect to the zonal dependency of T2 and T2* relaxation for the deep and superficial regions of healthy articular cartilage and cartilage repair tissue. There was a statistically significant correlation between T2 and T2* values. Both parameters demonstrated similar spatial dependency, with longer values measured toward the articular surface for healthy articular cartilage. No spatial variation was observed for cartilage repair tissue after MFX. Within this feasibility study, both T2 and T2* relaxation parameters demonstrated a similar response in the assessment of articular cartilage and cartilage repair tissue. The potential advantages of T2*-mapping of cartilage include faster imaging times and the opportunity for 3D acquisitions, thereby providing greater spatial resolution and complete coverage of the articular surface. (orig.)

  7. Effect of Collagen Type I or Type II on Chondrogenesis by Cultured Human Articular Chondrocytes

    NARCIS (Netherlands)

    Rutgers, M.; Saris, D.B.F.; Vonk, L.A.; Rijen, van M.H.P.; Akrum, V.; Langeveld, D.; Boxtel, van A.; Dhert, W.J.A.; Creemers, L.B.

    2013-01-01

    Introduction: Current cartilage repair procedures using autologous chondrocytes rely on a variety of carriers for implantation. Collagen types I and II are frequently used and valuable properties of both were shown earlier in vitro, although a preference for either was not demonstrated. Recently, ho

  8. Evaluation of influence of proteoglycans on hydration of articular cartilage with the use of ultrasound

    Directory of Open Access Journals (Sweden)

    Yi-yi YANG

    2015-04-01

    Full Text Available Objective To monitor the changes in hydration behaviour of articular cartilage induced by degradation of proteoglycans, and to explore the effect of proteoglycans on hydration behaviour of articular cartilage by using high-frequency ultrasound. Methods Twelve porcine patellae with smooth cartilage surface were prepared and equally divided into two groups: normal group without any enzyme treatment, and trypsin group they were treated with 0.25% trypsin for 8h to digest proteoglycan in the cartilage. The hydration behaviour of the cartilage tissue was scanned by high-frequency ultrasound system with a central frequency of 25MHz. Parameters including cartilage hydration strain and cartilage thickness were measured. The histopathological changes in the articular cartilage were observed under a light microscope. Results It took approximately 20min to reach equilibrium during the hydration process in the normal cartilages, while proteoglycan-degraded cartilage took only about 5min to achieve equilibrium. The equilibrium strain of normal cartilage was 3.5%±0.5%. The degradation of proteoglycans induced a significant decrease in equilibrium strain (1.8%±0.2%, P0.05. Conclusion Proteoglycans play an important role in hydration behaviour of articular cartilage. The degradation of proteoglycans could induce degeneration of cartilage structure and decrease in hydration behaviour after dehydration. DOI: 10.11855/j.issn.0577-7402.2015.03.03

  9. Preliminary investigation of intrinsic UV fluorescence spectroscopic changes associated with proteolytic digestion of bovine articular cartilage

    Science.gov (United States)

    Lewis, William; Padilla-Martinez, Juan-Pablo; Ortega-Martinez, Antonio; Franco, Walfre

    2016-03-01

    Degradation and destruction of articular cartilage is the etiology of osteoarthritis (OA), an entity second only to cardiovascular disease as a cause of disability in the United States. Joint mechanics and cartilage biochemistry are believed to play a role in OA; an optical tool to detect structural and chemical changes in articular cartilage might offer benefit for its early detection and treatment. The objective of the present study was to identify the spectral changes in intrinsic ultraviolet (UV) fluorescence of cartilage that occur after proteolytic digestion of cartilage. Bovine articular cartilage samples were incubated in varying concentrations of collagenase ranging from 10ug/mL up to 5mg/mL for 18 hours at 37°C, a model of OA. Pre- and post-incubation measurements were taken of the UV excitation-emission spectrum of each cartilage sample. Mechanical tests were performed to determine the pre- and post-digestion force/displacement ratio associated with indentation of each sample. Spectral changes in intrinsic cartilage fluorescence and stiffness of the cartilage were associated with proteolytic digestion. In particular, changes in the relative intensity of fluorescence peaks associated with pentosidine crosslinks (330 nm excitation, 390 nm emission) and tryptophan (290 nm excitation, 340 nm emission) were found to correlate with different degrees of cartilage digestion and cartilage stiffness. In principle, it may be possible to use UV fluorescence spectral data for early detection of damage to articular cartilage, and as a surrogate measure for cartilage stiffness.

  10. Delivering Agents Locally into Articular Cartilage by Intense MHz Ultrasound

    Science.gov (United States)

    Nieminen, Heikki J.; Ylitalo, Tuomo; Suuronen, Jussi-Petteri; Rahunen, Krista; Salmi, Ari; Saarakkala, Simo; Serimaa, Ritva; Hæggström, Edward

    2015-01-01

    There is no cure for osteoarthritis. Current drug delivery relies on systemic delivery or injections into the joint. Because articular cartilage (AC) degeneration can be local and drug exposure outside the lesion can cause adverse effects, localized drug delivery could permit new drug treatment strategies. We investigated whether intense megahertz ultrasound (frequency: 1.138 MHz, peak positive pressure: 2.7 MPa, Ispta: 5 W/cm2, beam width: 5.7 mm at −6 dB, duty cycle: 5%, pulse repetition frequency: 285 Hz, mechanical index: 1.1) can deliver agents into AC without damaging it. Using ultrasound, we delivered a drug surrogate down to a depth corresponding to 53% depth of the AC thickness without causing histologically detectable damage to the AC. This may be important because early osteoarthritis typically exhibits histopathologic changes in the superficial AC. In conclusion, we identify intense megahertz ultrasound as a technique that potentially enables localized non-destructive delivery of osteoarthritis drugs or drug carriers into articular cartilage. PMID:25922135

  11. Therapeutic effect of the saponin fraction from Clematis chinensis Osbeck roots on osteoarthritis induced by monosodium iodoacetate through protecting articular cartilage.

    Science.gov (United States)

    Wu, Wenjun; Xu, Xianxiang; Dai, Yue; Xia, Lunzhu

    2010-04-01

    The objective of the present study was to investigate the effect of the saponin fraction from Clematis chinensis Osbeck roots (SFC) on an osteoarthritis model in rats and to explore its underlying mechanisms. Osteoarthritis was induced by intraarticular injection of monosodium iodoacetate (MIA) into knee joints of rats, and SFC and diclofenac were orally administered once a day for 28 consecutive days. Joint swelling, macroscopic observation, histological assessment and proteoglycan (PG) degradation were examined. In vitro, cultured rabbit chondrocytes were stimulated with MIA and sodium nitroprusside (SNP), respectively. The effects of SFC on MIA- and SNP-induced chondrocyte injury were examined by MTT assay. It was shown that SFC (50, 100, 200 mg/kg) dose-dependently reduced cartilage injury and PG degradation induced by MIA. Diclofenac (4 mg/kg) only slightly alleviated cartilage injury and PG degradation. SFC also prevented SNP- or MIA-induced rabbit chondrocyte impairment. These results indicate that SFC is effective in ameliorating joint destruction and cartilage erosion in MIA-induced osteoarthritic in rats, and the mechanisms of action for protecting articular cartilage are through preventing extracellular matrix degradation and chondrocyte injury. PMID:19655297

  12. Multiphasic modeling of charged solute transport across articular cartilage: Application of multi-zone finite-bath model.

    Science.gov (United States)

    Arbabi, Vahid; Pouran, Behdad; Weinans, Harrie; Zadpoor, Amir A

    2016-06-14

    Charged and uncharged solutes penetrate through cartilage to maintain the metabolic function of chondrocytes and to possibly restore or further breakdown the cartilage tissue in different stages of osteoarthritis. In this study the transport of charged solutes across the various zones of cartilage was quantified, taken into account the physicochemical interactions between the solute and the cartilage constituents. A multiphasic finite-bath finite element (FE) model was developed to simulate equine cartilage diffusion experiments that used a negatively charged contrast agent (ioxaglate) in combination with serial micro-computed tomography (micro-CT) to measure the diffusion. By comparing the FE model with the experimental data both the diffusion coefficient of ioxaglate and the fixed charge density (FCD) were obtained. In the multiphasic model, cartilage was divided into multiple (three) zones to help understand how diffusion coefficient and FCD vary across cartilage thickness. The direct effects of charged solute-FCD interaction on diffusion were investigated by comparing the diffusion coefficients derived from the multiphasic and biphasic-solute models. We found a relationship between the FCD obtained by the multiphasic model and ioxaglate partitioning obtained from micro-CT experiments. Using our multi-zone multiphasic model, diffusion coefficient of the superficial zone was up to ten-fold higher than that of the middle zone, while the FCD of the middle zone was up to almost two-fold higher than that of the superficial zone. In conclusion, the developed finite-bath multiphasic model provides us with a non-destructive method by which we could obtain both diffusion coefficient and FCD of different cartilage zones. The outcomes of the current work will also help understand how charge of the bath affects the diffusion of a charged molecule and also predict the diffusion behavior of a charged solute across articular cartilage. PMID:27033729

  13. Biochemical analysis of normal articular cartilage in horses.

    Science.gov (United States)

    Vachon, A M; Keeley, F W; McIlwraith, C W; Chapman, P

    1990-12-01

    Articular cartilage specimens from the distal articular surface of 32 radiocarpal bones from 24 2- to 5-year-old horses were analyzed. The total collagen content was determined on the basis of the 4-hydroxyproline content, using a colorimetric method. A method for estimating the proportions of types-I and -II collagen by measuring spectrophotometric densities of specific cyanogen bromide peptide bands from mixtures of types-I and -II collagen on sodium dodecyl sulfate-polyacrylamide gels was used. The cyanogen bromide peptides representative of each collagen types-I and -II were identified. The peptide ratios were then computed for each of several standards of type-I and -II mixtures. A standard curve was derived from the correlation between these ratios and the corresponding proportions of type-II collagen in standard mixtures. Galactosamine and glucosamine content (hexosamines) were measured by ion chromatography. The galactosamine-to-glucosamine ratio, chondroitin sulfate and keratan sulfate values, and total glycosaminoglycan content were derived from the measured hexosamine content. The total collagen content averaged 556 mg/g (55.6 mg/100 mg) of tissue (dry weight, [dw]). Type-II collagen was the major collagen type in normal articular cartilage specimens. The ratio of the area under the alpha 1 (II)CB10 peak to the area under the alpha 1 (I)CB 7,8 + alpha 1 (II)CB11 peak was a second-order polynomial function of the proportion of type-II collagen in the specimens. The mean galactosamine and glucosamine content were 20.6 mg/g and 7.9 mg/g (dw), respectively. The mean galactosamine-to-glucosamine ratio was 3.74 +/- 0.62.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2085215

  14. Articular Cartilage Thickness Measured with US is Not as Easy as It Appears

    DEFF Research Database (Denmark)

    Torp-Pedersen, Søren; Bartels, E. M.; Wilhjelm, Jens E.;

    2011-01-01

    Background: Theoretically, the high spatial resolution of US makes it well suited to monitor the decrease in articular cartilage thickness in osteoarthritis. A requirement is, however, that the borders of the cartilage are correctly identified and that the cartilage ismeasured under orthogonal in...

  15. Articular cartilage thickness measured with US is not as easy as it appears

    DEFF Research Database (Denmark)

    Torp-Pedersen, S; Bartels, E M; Wilhjelm, Jens E.;

    2011-01-01

    Theoretically, the high spatial resolution of US makes it well suited to monitor the decrease in articular cartilage thickness in osteoarthritis. A requirement is, however, that the borders of the cartilage are correctly identified and that the cartilage is measured under orthogonal insonation. I...

  16. Chondrocyte Senescence and Telomere Regulation: Implications in Cartilage Aging and Cancer (A Brief Review)

    OpenAIRE

    Mollano, Anthony V; Martin, James A.; Buckwalter, Joseph A

    2002-01-01

    Recent studies on osteoarthritis and the cartilage aging in our laboratory demonstrate that chronologic age correlates with molecular changes in human chondrocytes that affect cell cycle control and replicative life span. These findings indicate that age-related changes in chondrocytes may explain the heightened risk for development of primary osteoarthritis (OA) with increasing age. Concomitant studies of human chondrosarcoma suggest that these aging mechanisms may also play a role in preven...

  17. Regeneration of articular cartilage using adipose stem cells.

    Science.gov (United States)

    Im, Gun-Il

    2016-07-01

    Articular cartilage (AC) has limited potential for self-regeneration and damage to AC eventually leads to the development and progression of osteoarthritis (OA). Cell implantation strategies have emerged as a new treatment modality to regenerate AC. Adipose stem cells/adipose-derived stromal cells (ASCs) have gained attention due to their abundance, excellent proliferative potential, and minimal morbidity during harvest. These advantages lower the cost of cell therapy by circumventing time-consuming procedure of culture expansion. ASCs have drawn attention as a potential source for cartilage regeneration since the feasibility of chondrogenesis from ASCs was first reported. After several groups reported inferior chondrogenesis from ASCs, numerous methods were devised to overcome the intrinsic properties. Most in vivo animal studies have reported good results using predifferentiated or undifferentiated, autologous or allogeneic ASCs to regenerate cartilage in osteochondral defects or surgically-induced OA. In this review, we summarize literature on the isolation and in vitro differentiation processes of ASCs, in vivo studies to regenerate AC in osteochondral defects and OA using ASCs, and clinical applications of ASCs. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1830-1844, 2016. PMID:26990234

  18. Deginerative changes of femoral articular cartilage in the knee : comparative study of specimen sonography and pathology

    International Nuclear Information System (INIS)

    To determine the sonographic findings of degenerative change in femoral articular cartilage of the knee by comparative study of specimen sonography and pathology. We obtained 40 specimens of cartilage of the femur (20 medial and 20 lateral condylar) from 20 patients with osteoarthritis of the knee who had undergone total knee replacement. The specimens were placed in a saline-filled container and sonography was performed using a 10-MHz linear transducer. Sonographic abnormalities were evaluated at the cartilage surface, within the cartilage, and at the bone-cartilage interface, and were compared with the corresponding pathologic findings. In addition, cartilage thickness was measured at a representative portion of each femoral cartilage specimen and was compared with the thickness determined by sonography. 'Dot' lesions, irregularity or loss of the hyperechoic line, were demonstrated by sonography at the saline-cartilage interface of 14 cartilages. Pathologic examination showed that these findings corresponded to cleft, detachment, erosion, and degeneration. Irregularities in the hyperechoic line at the bone-cartilage interface were revealed by sonography in eight cartilages and were related to irregularity or loss of tidemark, downward displacement of the cartilage, and subchondral callus formation. Dot lesions, corresponding to cleft and degeneration, were noted within one cartilage. Cartilage thickness measured on specimen and by sonography showed no significant difference (p=0.446). Specimen sonography suggested that articular cartilage underwent degenerative histopathological change. Cartilage thickness measured by sonography exactly reflected real thickness

  19. Gold Nanoparticles of Diameter 13 nm Induce Apoptosis in Rabbit Articular Chondrocytes

    Science.gov (United States)

    Huang, Hao; Quan, Ying-yao; Wang, Xiao-ping; Chen, Tong-sheng

    2016-05-01

    Gold nanoparticles (AuNPs) have been widely used in biomedical science including antiarthritic agents, drug loading, and photothermal therapy. In this report, we studied the effects of AuNPs with diameters of 3, 13, and 45 nm, respectively, on rabbit articular chondrocytes. AuNPs were capped with citrate and their diameter and zeta potential were measured by dynamic light scattering (DLS). Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay after the rabbit articular chondrocytes were pre-incubated with 3, 13, and 45 nm AuNPs, respectively, for 24 h. Flow cytometry (FCM) analysis with annexin V/propidium iodide (PI) double staining and fluorescence imaging with Hoechst 33258 staining were used to determine the fashion of AuNPs-induced chondrocyte death. Further, 13 nm AuNPs (2 nM) significantly induced chondrocyte death accompanying apoptotic characteristics including mitochondrial damage, externalization of phosphatidylserine and nuclear concentration. However, 3 nm AuNPs (2 nM) and 45 nm (0.02 nM) AuNPs did not induce cytotoxicity in chondrocytes. Although 13 nm AuNPs (2 nM) increased the intracellular reactive oxygen species (ROS) level, pretreatment with Nacetyl cysteine (NAC), a ROS scavenger, did not prevent the cytotoxicity induced by 13 nm AuNPs, indicating that 13 nm AuNPs (2 nM) induced ROS-independent apoptosis in chondrocytes. These results demonstrate the size-dependent cytotoxicity of AuNPs in chondrocytes, which must be seriously considered when using AuNPs for treatment of osteoarthritis (OA).

  20. Gold Nanoparticles of Diameter 13 nm Induce Apoptosis in Rabbit Articular Chondrocytes.

    Science.gov (United States)

    Huang, Hao; Quan, Ying-Yao; Wang, Xiao-Ping; Chen, Tong-Sheng

    2016-12-01

    Gold nanoparticles (AuNPs) have been widely used in biomedical science including antiarthritic agents, drug loading, and photothermal therapy. In this report, we studied the effects of AuNPs with diameters of 3, 13, and 45 nm, respectively, on rabbit articular chondrocytes. AuNPs were capped with citrate and their diameter and zeta potential were measured by dynamic light scattering (DLS). Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay after the rabbit articular chondrocytes were pre-incubated with 3, 13, and 45 nm AuNPs, respectively, for 24 h. Flow cytometry (FCM) analysis with annexin V/propidium iodide (PI) double staining and fluorescence imaging with Hoechst 33258 staining were used to determine the fashion of AuNPs-induced chondrocyte death. Further, 13 nm AuNPs (2 nM) significantly induced chondrocyte death accompanying apoptotic characteristics including mitochondrial damage, externalization of phosphatidylserine and nuclear concentration. However, 3 nm AuNPs (2 nM) and 45 nm (0.02 nM) AuNPs did not induce cytotoxicity in chondrocytes. Although 13 nm AuNPs (2 nM) increased the intracellular reactive oxygen species (ROS) level, pretreatment with Nacetyl cysteine (NAC), a ROS scavenger, did not prevent the cytotoxicity induced by 13 nm AuNPs, indicating that 13 nm AuNPs (2 nM) induced ROS-independent apoptosis in chondrocytes. These results demonstrate the size-dependent cytotoxicity of AuNPs in chondrocytes, which must be seriously considered when using AuNPs for treatment of osteoarthritis (OA). PMID:27178054

  1. Curcumin synergizes with resveratrol to stimulate the MAPK signaling pathway in human articular chondrocytes in vitro.

    Science.gov (United States)

    Shakibaei, Mehdi; Mobasheri, Ali; Buhrmann, Constanze

    2011-05-01

    The mitogen-activated protein kinase (MAPK) pathway is stimulated in differentiated chondrocytes and is an important signaling cascade for chondrocyte differentiation and survival. Pro-inflammatory cytokines such as interleukin 1β (IL-1β) play important roles in the pathogenesis of osteoarthritis (OA) and rheumatoid arthritis (RA). In this study, we investigated whether curcumin and resveratrol can synergistically inhibit the catabolic effects of IL-1β, specifically the inhibition of the MAPK and subsequent apoptosis in human articular chondrocytes. Chondrocytes were either left untreated or treated with 10 ng/ml IL-1β or 1 μM U0126, a specific inhibitor of MAPK pathway alone for the indicated time periods or pre-treated with 10 μM curcumin, 10 μM resveratrol or 10 μM resveratrol and 10 μM curcumin for 4 h followed by co-treatment with 10 ng/ml IL-1β or 1 μM U0126 and 10 μM resveratrol, 10 μM curcumin or 10 μM resveratrol and 10 μM curcumin for the indicated time periods. Cultures were evaluated by immunoblotting and transmission electron microscopy. Incubation of chondrocytes with IL-1β resulted in induction of apoptosis, downregulation of β1-integrins and the extracellular signal-regulated kinase 1/2 (Erk1/2). Interestingly, U0126 induced apoptosis and blocked the above-mentioned proteins in a similar way to IL-1β. Furthermore, curcumin and resveratrol inhibited IL-1β- or U0126-induced apoptosis and downregulation of β1-integrins and Erk1/2 in human articular chondrocytes. These results suggest that combining these two natural compounds activates MEK/Erk signaling, a pathway that is involved in the maintenance of chondrocyte differentiation and survival. PMID:21484156

  2. PKCa Agonists Enhance the Protective Effect of Hyaluronic Acid on Nitric Oxide-Induced Apoptosis of Articular Chondrocytes in Vitro

    Directory of Open Access Journals (Sweden)

    Jian-lin Zhou

    2013-12-01

    The results may be showed that PKCa regulate the expresion of caspase-3, which contribute to the apoptosis of chondrocytes induced by NO. PKC α agonists enhance the protective effect of hyaluronic acid on nitric oxide-induced articular chondrocytes apoptosis.

  3. Hyperosmolarity regulates SOX9 mRNA posttranscriptionally in human articular chondrocytes

    OpenAIRE

    Tew, Simon R.; Peffers, Mandy J.; McKay, Tristan R; Lowe, Emma T.; Khan, Wasim S; Hardingham, Timothy E.; Clegg, Peter D

    2009-01-01

    The transcription factor SOX9 regulates cartilage extracellular matrix gene expression and is essential for chondrocyte differentiation. We previously showed that activation of p38 MAPK by cycloheximide in human chondrocytes leads to stabilization of SOX9 mRNA (Tew SR and Hardingham TE. J Biol Chem 281: 39471–39479, 2006). In this study we investigated whether regulation of p38 MAPK caused by changes in osmotic pressure could control SOX9 mRNA levels expression by a similar mechanism. Primary...

  4. A biphasic finite element study on the role of the articular cartilage superficial zone in confined compression

    OpenAIRE

    Guo, Hongqiang; Maher, Suzanne A; Torzilli, Peter A.

    2014-01-01

    The aim of this study was to investigate the role of the superficial zone on the mechanical behavior of articular cartilage. Confined compression of articular cartilage was modeled using a biphasic finite element analysis to calculate the one-dimensional deformation of the extracellular matrix (ECM) and movement of the interstitial fluid through the ECM and articular surface. The articular cartilage was modeled as an inhomogeneous, nonlinear hyperelastic biphasic material with depth and strai...

  5. Viscoelastic properties of bovine knee joint articular cartilage: dependency on thickness and loading frequency

    OpenAIRE

    Espino, Daniel M; Shepherd, Duncan ET; Hukins, David WL

    2014-01-01

    Background The knee is an incongruent joint predisposed to developing osteoarthritis, with certain regions being more at risk of cartilage degeneration even in non-osteoarthrosed joints. At present it is unknown if knee regions prone to cartilage degeneration have similar storage and/or loss stiffness, and frequency-dependent trends, to other knee joint cartilage. The aim of this study was to determine the range of frequency-dependent, viscoelastic stiffness of articular cartilage across the ...

  6. Contact mechanics of articular cartilage layers asymptotic models

    CERN Document Server

    Argatov, Ivan

    2015-01-01

    This book presents a comprehensive and unifying approach to articular contact mechanics with an emphasis on frictionless contact interaction of thin cartilage layers. The first part of the book (Chapters 1–4) reviews the results of asymptotic analysis of the deformational behavior of thin elastic and viscoelastic layers. A comprehensive review of the literature is combined with the authors’ original contributions. The compressible and incompressible cases are treated separately with a focus on exact solutions for asymptotic models of frictionless contact for thin transversely isotropic layers bonded to rigid substrates shaped like elliptic paraboloids. The second part (Chapters 5, 6, and 7) deals with the non-axisymmetric contact of thin transversely isotropic biphasic layers and presents the asymptotic modelling methodology for tibio-femoral contact. The third part of the book consists of Chapter 8, which covers contact problems for thin bonded inhomogeneous transversely isotropic elastic layers, and Cha...

  7. Botanical Extracts from Rosehip (Rosa canina), Willow Bark (Salix alba), and Nettle Leaf (Urtica dioica) Suppress IL-1 beta-Induced NF-kappa B Activation in Canine Articular Chondrocytes

    OpenAIRE

    Shakibaei, Mehdi; Allaway, David; Nebrich, Simone; Mobasheri, Ali

    2012-01-01

    The aim of this study was to characterize the anti-inflammatory mode of action of botanical extracts from rosehip (Rosa canina), willow bark (Salix alba), and nettle leaf (Urtica dioica) in an in vitro model of primary canine articular chondrocytes. Methods. The biological effects of the botanical extracts were studied in chondrocytes treated with IL-1 beta for up to 72h. Expression of collagen type II, cartilage-specific proteoglycan (CSPG), beta 1-integrin, SOX-9, COX-2, and MMP-9 and MMP-1...

  8. Botanical Extracts from Rosehip (Rosa canina), Willow Bark (Salix alba), and Nettle Leaf (Urtica dioica) Suppress IL-1β-Induced NF-κB Activation in Canine Articular Chondrocytes

    OpenAIRE

    Mehdi Shakibaei; David Allaway; Simone Nebrich; Ali Mobasheri

    2012-01-01

    The aim of this study was to characterize the anti-inflammatory mode of action of botanical extracts from rosehip (Rosa canina), willow bark (Salix alba), and nettle leaf (Urtica dioica) in an in vitro model of primary canine articular chondrocytes. Methods. The biological effects of the botanical extracts were studied in chondrocytes treated with IL-1β for up to 72 h. Expression of collagen type II, cartilage-specific proteoglycan (CSPG), β1-integrin, SOX-9, COX-2, and MMP-9 and MMP-13 was e...

  9. Minced articular cartilage--basic science, surgical technique, and clinical application.

    Science.gov (United States)

    McCormick, Frank; Yanke, Adam; Provencher, Matthew T; Cole, Brian J

    2008-12-01

    Minced articular cartilage procedures are attractive surgical approaches for repairing articular cartilage, as they are 1-staged, autologous, and inserted on a carrier that can potentially be placed arthroscopically. The principle of mincing the autologous donor cartilage is to create a larger surface area for cartilage expansion. Placement on a scaffold carrier allows for a chondro-inductive and chondro-conductive milieu. Early animal and preclinical models have demonstrated hyaline-like tissue repair. Further work needs to be conducted in this promising approach. PMID:19011553

  10. Berberine induces dedifferentiation by actin cytoskeleton reorganization via phosphoinositide 3-kinase/Akt and p38 kinase pathways in rabbit articular chondrocytes.

    Science.gov (United States)

    Yu, Seon-Mi; Cho, Hongsik; Kim, Gwang-Hoon; Chung, Ki-Wha; Seo, Sung-Yum; Kim, Song-Ja

    2016-04-01

    Osteoarthritis is a nonrheumatologic joint disease characterized by progressive degeneration of the cartilage extracellular matrix. Berberine (BBR) is an isoquinoline alkaloid used in traditional Chinese medicine, the majority of which is extracted from Huang Lian (Coptis chinensis). Although numerous studies have revealed the anticancer activity of BBR, its effects on normal cells, such as chondrocytes, and the molecular mechanisms underlying its actions remain elusive. Therefore, we examined the effects of BBR on rabbit articular chondrocytes, and the underlying molecular mechanisms, focusing on actin cytoskeletal reorganization. BBR induced dedifferentiation by inhibiting activation of phosphoinositide-3(PI3)-kinase/Akt and p38 kinase. Furthermore, inhibition of p38 kinase and PI3-kinase/Akt with SB203580 and LY294002, respectively, accelerated the BBR-induced dedifferentiation. BBR also caused actin cytoskeletal architecture reorganization and, therefore, we investigated if these effects were involved in the dedifferentiation. Disruption of the actin cytoskeleton by cytochalasin D reversed the BBR-induced dedifferentiation by activating PI3-kinase/Akt and p38 kinase. In contrast, the induction of actin filament aggregation by jasplakinolide accelerated the BBR-induced dedifferentiation via PI3-kinase/Akt inhibition and p38 kinase activation. Taken together, these data suggest that BBR strongly induces dedifferentiation, and actin cytoskeletal reorganization is a crucial requirement for this effect. Furthermore, the dedifferentiation activity of BBR appears to be mediated via PI3-kinase/Akt and p38 kinase pathways in rabbit articular chondrocytes. PMID:26851252

  11. Multi-parametric MRI characterization of enzymatically degraded articular cartilage.

    Science.gov (United States)

    Nissi, Mikko J; Salo, Elli-Noora; Tiitu, Virpi; Liimatainen, Timo; Michaeli, Shalom; Mangia, Silvia; Ellermann, Jutta; Nieminen, Miika T

    2016-07-01

    Several laboratory and rotating frame quantitative MRI parameters were evaluated and compared for detection of changes in articular cartilage following selective enzymatic digestion. Bovine osteochondral specimens were subjected to 44 h incubation in control medium or in collagenase or chondroitinase ABC to induce superficial collagen or proteoglycan (glycosaminoglycan) alterations. The samples were scanned at 9.4 T for T1 , T1 Gd (dGEMRIC), T2 , adiabatic T1 ρ , adiabatic T2 ρ , continuous-wave T1 ρ , TRAFF2 , and T1 sat relaxation times and for magnetization transfer ratio (MTR). For reference, glycosaminoglycan content, collagen fibril orientation and biomechanical properties were determined. Changes primarily in the superficial cartilage were noted after enzymatic degradation. Most of the studied parameters were sensitive to the destruction of collagen network, whereas glycosaminoglycan depletion was detected only by native T1 and T1 Gd relaxation time constants throughout the tissue and by MTR superficially. T1 , adiabatic T1 ρ , adiabatic T2 ρ , continuous-wave T1 ρ , and T1 sat correlated significantly with the biomechanical properties while T1 Gd correlated with glycosaminoglycan staining. The findings indicated that most of the studied MRI parameters were sensitive to both glycosaminoglycan content and collagen network integrity, with changes due to enzymatic treatment detected primarily in the superficial tissue. Strong correlation of T1 , adiabatic T1ρ , adiabatic T2 ρ , continuous-wave T1 ρ , and T1 sat with the altered biomechanical properties, reflects that these parameters were sensitive to critical functional properties of cartilage. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1111-1120, 2016. PMID:26662555

  12. Hyaluronan fragments activate nitric oxide synthase and the production of nitric oxide by articular chondrocytes

    OpenAIRE

    Iacob, Stanca; Knudson, Cheryl B.

    2005-01-01

    Chondrocyte CD44 receptors anchor hyaluronan to the cell surface, enabling the assembly and retention of proteoglycan aggregates in the pericellular matrix. Hyaluronan–CD44 interactions also provide signaling important for maintaining cartilage homeostasis. Disruption of chondrocyte–hyaluronan contact alters CD44 occupancy, initiating alternative signaling cascades. Treatment with hyaluronan oligosaccharides is one approach to uncouple CD44 receptors from its native ligand, hyaluronan. In bov...

  13. Effects of immobilization on thickness of superficial zone of articular cartilage of patella in rats

    Directory of Open Access Journals (Sweden)

    Khadija Iqbal

    2012-01-01

    Conclusion: Each segment of superficial zone behaves differentially on immobilization and remobilization. Perhaps a much longer duration of remobilization is required to reverse changes of immobilization in articular cartilage and plays a significant role in knee joint movements.

  14. A Validated Model of the Pro- and Anti-Inflammatory Cytokine Balancing Act in Articular Cartilage Lesion Formation

    OpenAIRE

    Wang, Xiayi; Brouillette, Marc J.; Ayati, Bruce P; Martin, James A.

    2015-01-01

    Traumatic injuries of articular cartilage result in the formation of a cartilage lesion and contribute to cartilage degeneration and the risk of osteoarthritis (OA). A better understanding of the framework for the formation of a cartilage lesion formation would be helpful in therapy development. Toward this end, we present an age and space-structured model of articular cartilage lesion formation after a single blunt impact. This model modifies the reaction-diffusion-delay models in Graham et ...

  15. Protein-based injectable hydrogels towards the regeneration of articular cartilage

    OpenAIRE

    Poveda Reyes, Sara

    2016-01-01

    [EN] Articular cartilage is a tissue with low capacity for self-restoration due to its avascularity and low cell population. It is located on the surface of the subchondral bone covering the diarthrodial joints. Degeneration of articular cartilage can appear in athletes, in people with genetic degenerative processes (osteoarthritis or rheumatoid arthritis) or due to a trauma; what produces pain, difficulties in mobility and progressive degeneration that finally leads to joint failure. Self-re...

  16. Ontogeny of rat chondrocyte proliferation: studies in embryo, adult and osteoarthritic (OA) cartilage

    Institute of Scientific and Technical Information of China (English)

    Madaí A GóMEZ-CAMARILLO; Juan B.KOURI

    2005-01-01

    The aim of this work was to study the ontogeny of chondrocyte cell division using embryo, adult and osteoarthritic (OA) cartilage. We searched for mitosis phases and performed a comparative evaluation of mitotic index, basic fibroblast growth factor b (FGFb), transforming growth factor β1 (TGF-β1) receptors, cyclin dependent kinase (CDK1)and Cyclin-B expression in fetal, neonate, 3, 5, 8 weeks old rats and experimental OA. Our results showed that mitosis phases were observed in all normal cartilage studied, although, we found a decrease in mitotic index in relation to tissue development. No mitosis was detected in OA cartilage. We also found a statistical significant reduction in cell number in OA cartilage, compared with the normal tissue. Furthermore, FGFb and TGF-β1 receptors diminished in relation to tissue development, and were very scarce in experimental OA. Western blot assays showed CDK-1 expression in all cases, including human-OA cartilage. Similar results were observed for Cyclin-B, except for 8 weeks, when it was not expressed. Our results suggest that cell division seems to be scarce, if not absent within the OA cartilage studied.Nevertheless, the existence of factors essential for cell division leaves open the question concerning chondrocyte proliferation in OA cartilage, which is likely to be present in the early stages of the disease.

  17. Effect of microcavitary alginate hydrogel with different pore sizes on chondrocyte culture for cartilage tissue engineering

    International Nuclear Information System (INIS)

    In our previous work, a novel microcavitary hydrogel was proven to be effective for proliferation of chondrocytes and maintenance of chondrocytic phenotype. In present work, we further investigated whether the size of microcavity would affect the growth and the function of chondrocytes. By changing the stirring rate, gelatin microspheres in different sizes including small size (80–120 μm), middle size (150–200 μm) and large size (250–300 μm) were prepared. And then porcine chondrocytes were encapsulated into alginate hydrogel with various sizes of gelatin microspheres. Cell Counting Kit-8 (CCK-8), Live/dead staining and real-time PCR were used to analyze the effect of the pore size on cell proliferation and expression of specific chondrocytic genes. According to all the data, cells cultivated in microcavitary hydrogel, especially in small size, had preferable abilities of proliferation and higher expression of cartilaginous markers including type II collagen, aggrecan and cartilage oligomeric matrix protein (COMP). Furthermore, it was shown by western blot assay that the culture of chondrocytes in microcavitary hydrogel could improve the proliferation of cells potentially by inducing the Erk1/2-MAPK pathway. Taken together, this study demonstrated that chondrocytes favored microcavitary alginate hydrogel with pore size within the range of 80–120 μm for better growth and ECM synthesis, in which Erk1/2 pathway was involved. This culture system would be promising for cartilage tissue engineering. - Highlights: • A novel model with microcavitary structure was set up to study the interaction between cells and materials. • Microcavitary alginate hydrogel could enhance the proliferation of chondrocytes and promote the expression of cartilaginous genes as compared with plain alginate hydrogel. • Cells in microcavitary alginate hydrogel with pore size within the range of 80–120 μm were capable of better growth and ECM synthesis

  18. Effect of microcavitary alginate hydrogel with different pore sizes on chondrocyte culture for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Lei; Yao, Yongchang [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Wang, Dong-an, E-mail: DAWang@ntu.edu.sg [National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Division of Bioengineering, School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637457 (Singapore); Chen, Xiaofeng, E-mail: chenxf@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China)

    2014-01-01

    In our previous work, a novel microcavitary hydrogel was proven to be effective for proliferation of chondrocytes and maintenance of chondrocytic phenotype. In present work, we further investigated whether the size of microcavity would affect the growth and the function of chondrocytes. By changing the stirring rate, gelatin microspheres in different sizes including small size (80–120 μm), middle size (150–200 μm) and large size (250–300 μm) were prepared. And then porcine chondrocytes were encapsulated into alginate hydrogel with various sizes of gelatin microspheres. Cell Counting Kit-8 (CCK-8), Live/dead staining and real-time PCR were used to analyze the effect of the pore size on cell proliferation and expression of specific chondrocytic genes. According to all the data, cells cultivated in microcavitary hydrogel, especially in small size, had preferable abilities of proliferation and higher expression of cartilaginous markers including type II collagen, aggrecan and cartilage oligomeric matrix protein (COMP). Furthermore, it was shown by western blot assay that the culture of chondrocytes in microcavitary hydrogel could improve the proliferation of cells potentially by inducing the Erk1/2-MAPK pathway. Taken together, this study demonstrated that chondrocytes favored microcavitary alginate hydrogel with pore size within the range of 80–120 μm for better growth and ECM synthesis, in which Erk1/2 pathway was involved. This culture system would be promising for cartilage tissue engineering. - Highlights: • A novel model with microcavitary structure was set up to study the interaction between cells and materials. • Microcavitary alginate hydrogel could enhance the proliferation of chondrocytes and promote the expression of cartilaginous genes as compared with plain alginate hydrogel. • Cells in microcavitary alginate hydrogel with pore size within the range of 80–120 μm were capable of better growth and ECM synthesis.

  19. Cartilage in facet joints of patients with ankylosing spondylitis (AS) shows signs of cartilage degeneration rather than chondrocyte hypertrophy: implications for joint remodeling in AS

    OpenAIRE

    Bleil, Janine; Sieper, Joachim; Maier, Rene; Schlichting, Uwe; Hempfing, Axel; Syrbe, Uta; Appel, Heiner

    2015-01-01

    Introduction In ankylosing spondylitis (AS), joint remodeling leading to joint ankylosis involves cartilage fusion. Here, we analyzed whether chondrocyte hypertrophy is involved in cartilage fusion and subsequent joint remodeling in AS. Methods We assessed the expression of chondrocyte hypertrophy markers runt-related transcription factor 2 (Runx2), type X collagen (COL10), matrix metalloproteinase 13 (MMP13), osteocalcin and beta-catenin and the expression of positive bone morphogenic protei...

  20. MR diffusion weighted imaging experimental study on early stages of articular cartilage degeneration of knee

    International Nuclear Information System (INIS)

    Objective: To study the appearance of MR diffusion weighted imaging in early stages of cartilage degeneration and to detect its values. Methods: In 20 goat left knees, intra- articular injection of 5 units of papain was performed causing a loss of cartilage proteoglycan. Twenty right knees were used as control group. MR diffusion weighted imaging was performed at 24 hours after intra-articular injection of papain. ADC of each part of articular cartilage was measured and compared with each other. The proteoglycan content was measured biochemically and histochemically. Routine MRI and DWI were performed in 100 patients with osteoarthritis and 20 healthy people. The ADC of each interested part of articular cartilage was measured and compared with each other. Results: In experimental control group, the ADCav of articular cartilage was (14.2±2.3) x 10-4 mm2/s. In early stages of cartilage degeneration group, the ADCav of articular cartilage was (17.5±4.2) x 10-4 mm2/s. The ADCav of the control group was lower than that of the early stages of cartilage degeneration group (t=2.709; P=0.016). The proteloglycan content of articular cartilage was 4.22 x 106 μg/kg in control group, and 0.82 x 106 μg/kg in experimental group at 24 hours after injection of papain. The difference between control group and experimental group was significant (t=2.705, P=0.018). In healthy people, the ADCav of articular cartilage was (7.6±2.2) x 10-4 mm2/s. In osteoarthritis group, the ADCav of articular cartilage was (10.3±4.2) x 10-4 mm2/s. The ADCav in the healthy group was significantly lower than that in the osteoarthritis group (t=2.609,P=0.014). Conclusion: DWI is an useful method in detecting early stages of cartilage degeneration which can not be showed on routine sequences. (authors)

  1. Comparison of nonlinear mechanical properties of bovine articular cartilage and meniscus.

    Science.gov (United States)

    Danso, E K; Honkanen, J T J; Saarakkala, S; Korhonen, R K

    2014-01-01

    Nonlinear, linear and failure properties of articular cartilage and meniscus in opposing contact surfaces are poorly known in tension. Relationships between the tensile properties of articular cartilage and meniscus in contact with each other within knee joints are also not known. In the present study, rectangular samples were prepared from the superficial lateral femoral condyle cartilage and lateral meniscus of bovine knee joints. Tensile tests were carried out with a loading rate of 5mm/min until the tissue rupture. Nonlinear properties of the toe region, linear properties in larger strains, and failure properties of both tissues were analysed. The strain-dependent tensile modulus of the toe region, Young's modulus of the linear region, ultimate tensile stress and toughness were on average 98.2, 8.3, 4.0 and 1.9 times greater (p<0.05) for meniscus than for articular cartilage. In contrast, the toe region strain, yield strain and failure strain were on average 9.4, 3.1 and 2.3 times greater (p<0.05) for cartilage than for meniscus. There was a significant negative correlation between the strain-dependent tensile moduli of meniscus and articular cartilage samples within the same joints (r=-0.690, p=0.014). In conclusion, the meniscus possesses higher nonlinear and linear elastic stiffness and energy absorption capability before rupture than contacting articular cartilage, while cartilage has longer nonlinear region and can withstand greater strains before failure. These findings point out different load carrying demands that both articular cartilage and meniscus have to fulfil during normal physiological loading activities of knee joints. PMID:24182695

  2. Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair

    OpenAIRE

    Mithoefer, Kai; Saris, Daniel B.F.; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J.; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats

    2011-01-01

    Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for t...

  3. Cartilage-derived extracellular matrix extract promotes chondrocytic phenotype in three-dimensional tissue culture.

    Science.gov (United States)

    Youngstrom, Daniel W; Cakstina, Inese; Jakobsons, Eriks

    2016-05-01

    Cell transplantation is a promising regenerative therapy for cartilage degeneration. However, obtaining sufficient numbers of cells for this purpose is a challenge, due a lack of autologous donor tissue and the difficulty of culturing chondrocytes in vitro. Tissue engineering strategies that induce or maintain chondrocytic phenotype may solve these problems by (1) broadening the range of available donor tissue, and (2) facilitating the expansion of these cells while controlling phenotypic drift. In this study, bone marrow-derived mesenchymal stem cells (MSCs) and cartilage-derived cells (CDCs) were cultured on composite hydrogels containing agarose and homogenized cartilage extracellular matrix (ECM). MSCs cultured on agarose-ECM scaffolds did not show significant signs of chondrogenic differentiation in the absence of additional cues. However, CDCs cultured on agarose-ECM scaffolds proliferated more rapidly than their ECM-free counterparts and MSCs, while retaining chondrocytic morphology. These results were corroborated via expression of cartilage marker genes: in autologous constructs, SOX 9 expression was upregulated by 12.6 ± 5.3-fold, and COL II was upregulated by 2.0 ± 0.3-fold. Agarose-ECM composite hydrogels are therefore useful for expanding partially differentiated CDCs for applications in regenerative medicine. PMID:25707441

  4. X-ray dark field imaging of human articular cartilage: Possible clinical application to orthopedic surgery

    International Nuclear Information System (INIS)

    Despite its convenience and non-invasiveness on daily clinical use, standard X-ray radiography cannot show articular cartilage. We developed a novel type of X-ray dark field imaging (DFI), which forms images only by a refracted beam with very low background illumination. We examined a disarticulated distal femur and a shoulder joint with surrounding soft tissue and skin, both excised from a human cadaver at the BL20B2 synchrotron beamline at SPring-8. The field was 90 mm wide and 90 mm high. Articular cartilage of the disarticulated distal femur was obvious on DFI, but not on standard X-ray images. Furthermore, DFI allowed visualization in situ of articular cartilage of the shoulder while covered with soft tissue and skin. The gross appearance of the articular cartilage on the dissected section of the proximal humerus was identical to the cartilage shown on the DFI image. These results suggested that DFI could provide a clinically accurate method of assessing articular cartilage. Hence, DFI would be a useful imaging tool for diagnosing joint disease such as osteoarthritis

  5. Study on the Microstructure of Human Articular Cartilage/Bone Interface

    Institute of Scientific and Technical Information of China (English)

    Yaxiong Liu; Qin Lian; Jiankang He; Jinna Zhao; Zhongmin Jin; Dichen Li

    2011-01-01

    For improving the theory of gradient microstructure of cartilage/bone interface, human distal femurs were studied. Scanning Electron Microscope (SEM), histological sections and MicroCT were used to observe, measure and model the microstructure of cartilage/bone interface. The results showed that the cartilage/bone interface is in a hierarchical structure which is composed of four different tissue layers. The interlocking of hyaline cartilage and calcified cartilage and that of calcified cartilage and subchondral bone are in the manner of"protrusion-pore" with average diameter of 17.0 μm and 34.1 μm respectively. In addition, the cancellous bone under the cartilage is also formed by four layer hierarchical structure, and the adjacent layers are connected by bone trabecula in the shape of H, I and Y, forming a complex interwoven network structure. Finally, the simplified structure model of the cartilage/bone interface was proposed according to the natural articular cartilage/bone interface. The simplified model is a 4-layer gradient biomimetic structure, which corresponds to four different tissues of natural cartilage/bone interface. The results of this work would be beneficial to the design of bionic scaffold for the tissue engineering of articular cartilage/bone.

  6. Exosomes from IL-1β stimulated synovial fibroblasts induce osteoarthritic changes in articular chondrocytes

    OpenAIRE

    Kato, Tomohiro; Miyaki, Shigeru; Ishitobi, Hiroyuki; Nakamura, Yoshihiro; Nakasa, Tomoyuki; Lotz, Martin K.; Ochi, Mitsuo

    2014-01-01

    Introduction Osteoarthritis (OA) is a whole joint disease, and characterized by progressive degradation of articular cartilage, synovial hyperplasia, bone remodeling and angiogenesis in various joint tissues. Exosomes are a type of microvesicles (MVs) that may play a role in tissue-tissue and cell-cell communication in homeostasis and diseases. We hypothesized that exosomes function in a novel regulatory network that contributes to OA pathogenesis and examined the function of exosomes in comm...

  7. The application of POSS nanostructures in cartilage tissue engineering: the chondrocyte response to nanoscale geometry.

    Science.gov (United States)

    Oseni, Adelola O; Butler, Peter E; Seifalian, Alexander M

    2015-11-01

    Despite extensive research into cartilage tissue engineering (CTE), there is still no scaffold ideal for clinical applications. Various synthetic and natural polymers have been investigated in vitro and in vivo, but none have reached widespread clinical use. The authors investigate the potential of POSS-PCU, a synthetic nanocomposite polymer, for use in CTE. POSS-PCU is modified with silsesquioxane nanostructures that improve its biological and physical properties. The ability of POSS-PCU to support the growth of ovine nasoseptal chondrocytes was evaluated against a polymer widely used in CTE, polycaprolactone (PCL). Scaffolds with varied concentrations of the POSS molecule were also synthesized to investigate their effect on chondrocyte growth. Chondrocytes were seeded onto scaffold disks (PCU negative control; POSS-PCU 2%, 4%, 6%, 8%; PCL). Cytocompatibilty was evaluated using cell viability, total DNA, collagen and GAG assays. Chondrocytes cultured on POSS-PCU (2% POSS) scaffolds had significantly higher viability than PCL scaffolds (p PCU scaffolds compared with PCL (p > 0.05). POSS-PCU (6% and 8% POSS) had improved viability and proliferation over an 18 day culture period compared with 2% and 4% POSS-PCU (p PCU has excellent potential for use in CTE. It supports the growth of chondrocytes in vitro and the POSS modification significantly enhances the growth and proliferation of nasoseptal chondrocytes compared with traditional scaffolds such as PCL. PMID:23576328

  8. Micromass co-culture of human articular chondrocytes and human bone marrow mesenchymal stem cells to investigate stable neocartilage tissue formation in vitro

    Directory of Open Access Journals (Sweden)

    S Giovannini

    2010-10-01

    Full Text Available Cell therapies for articular cartilage defects rely on expanded chondrocytes. Mesenchymal stem cells (MSC represent an alternative cell source should their hypertrophic differentiation pathway be prevented. Possible cellular instruction between human articular chondrocytes (HAC and human bone marrow MSC was investigated in micromass pellets. HAC and MSC were mixed in different percentages or incubated individually in pellets for 3 or 6 weeks with and without TGF-beta1 and dexamethasone (±T±D as chondrogenic factors. Collagen II, collagen X and S100 protein expression were assessed using immunohistochemistry. Proteoglycan synthesis was evaluated applying the Bern score and quantified using dimethylmethylene blue dye binding assay. Alkaline phosphatase activity (ALP was detected on cryosections and soluble ALP measured in pellet supernatants. HAC alone generated hyaline-like discs, while MSC formed spheroid pellets in ±T±D. Co-cultured pellets changed from disc to spheroid shape with decreasing number of HAC, and displayed random cell distribution. In -T-D, HAC expressed S100, produced GAG and collagen II, and formed lacunae, while MSC did not produce any cartilage-specific proteins. Based on GAG, collagen type II and S100 expression chondrogenic differentiation occurred in -T-D MSC co-cultures. However, quantitative experimental GAG and DNA values did not differ from predicted values, suggesting only HAC contribution to GAG production. MSC produced cartilage-specific matrix only in +T+D but underwent hypertrophy in all pellet cultures. In summary, influence of HAC on MSC was restricted to early signs of neochondrogenesis. However, MSC did not contribute to the proteoglycan deposition, and HAC could not prevent hypertrophy of MSC induced by chondrogenic stimuli.

  9. Xenotransplantation of pig chondrocytes: therapeutic potential and barriers for cartilage repair.

    Science.gov (United States)

    Sommaggio, R; Uribe-Herranz, M; Marquina, M; Costa, C

    2016-01-01

    Transplantation may be the best option for the repair of many cartilage lesions including early osteoarthritis. Currently, autologous and allogeneic chondrocytes are grafted into cartilage defects to treat selected patients with moderate clinical success. However, their limited use justifies exploring novel therapies for cartilage repair. Xenotransplantation could become a solution by offering high cell availability, quality and genetic engineering capabilities. The rejection process of xenogeneic cartilage is thus being elucidated in order to develop counteractive strategies. Initial studies determined that pig cartilage xenografts are rejected by a slow process comprising humoral and cellular responses in which the galactose α1,3-galactose antigen participates. Since then, our group has identified key mechanisms of the human response to pig chondrocytes (PCs). In particular, human antibody and complement contribute to PC rejection by inducing a pro-inflammatory milieu. Furthermore, PCs express and up-regulate molecules which are functionally relevant for a variety of cellular immune responses (SLA-I, the potent co-stimulatory molecule CD86, and adhesion molecules VCAM-1 and ICAM-1). These participate by triggering a T cell response, as well as supporting a prominent role of the innate immune responses led by natural killer (NK) cells and monocytes/macrophages. Human NK cells lyse PCs by using selected NK activating receptors, whereas human monocytes are activated by PCs to secrete cytokines and chemokines. All this knowledge sets the bases for the development of genetic engineering approaches designed to avert rejection of xenogeneic chondrocytes and leads the way to developing new clinical applications for cartilage repair. PMID:27377665

  10. Characterization of human primary chondrocytes of osteoarthritic cartilage at varying severity

    Institute of Scientific and Technical Information of China (English)

    YIN Jing; YANG Zheng; CAO Yong-ping; GE Zi-gang

    2011-01-01

    Background There is a difficulty in evaluating the in vivo functionality of individual chondrocytes,and there is much heterogeneity among cartilage affected by osteoarthritis (OA).In this study,in vitro cultured chondrocytes harvested from varying stages of degeneration were studied as a projective model to further understand the pathogenesis of osteoarthritis.Methods Cartilage of varying degeneration of end-stage OA was harvested,while cell yield and matrix glycosaminoglycan (GAG) content were measured.Cell morphology,proliferation,and gene expression of collagen type Ⅰ,Ⅱ,and Ⅹ,aggrecan,matrix metalloproteinase 13 (MMP-13),and ADAMTS5 of the acquired chondrocytes were measured during subsequent in vitro culture.Results Both the number of cells and the GAG content increased with increasing severity of OA.Cell spreading area increased and gradually showed spindle-like morphology during in vitro culture.Gene expression of collagen type Ⅱ,collagen type X as well as GAG decreased with severity of cartilage degeneration,while expression of collagen type Ⅰ increased.Expression of MMP-13 increased with severity of cartilage degeneration,while expression of ADAMTS-5 remained stable.Expression of collagen type Ⅱ,X,GAG,and MMP-13 substantially decreased with in vitro culture.Expression of collagen type Ⅰ increased with in vitro cultures,while expression of ADAMTS 5 remained stable.Conclusions Expression of functional genes such as collagen type Ⅱ and GAG decreased during severe degeneration of OA cartilage and in vitro dedifferentiation.Gene expression of collagen Ⅰ and MMP-13 increased with severity of cartilage degeneration.

  11. Articular Cartilage Evaluation After TruFit Plug Implantation Analyzed by Delayed Gadolinium-Enhanced MRI of Cartilage (dGEMRIC)

    NARCIS (Netherlands)

    Bekkers, J.E.J.; Bartels, L.W.; Vincken, K.L.; Dhert, W.J.A.; Creemers, L.B.; Saris, D.B.F.

    2013-01-01

    Background: Quantitative MRI of articular cartilage has rapidly developed in recent years and provides the clinician with a noninvasive tool to determine the biological consequence of an intervention. Purpose: To evaluate the quality of intra-articular cartilage, using the dGEMRIC scanning techniqu

  12. Articular cartilage repair with recombinant human type II collagen/polylactide scaffold in a preliminary porcine study.

    Science.gov (United States)

    Muhonen, Virpi; Salonius, Eve; Haaparanta, Anne-Marie; Järvinen, Elina; Paatela, Teemu; Meller, Anna; Hannula, Markus; Björkman, Mimmi; Pyhältö, Tuomo; Ellä, Ville; Vasara, Anna; Töyräs, Juha; Kellomäki, Minna; Kiviranta, Ilkka

    2016-05-01

    The purpose of this study was to investigate the potential of a novel recombinant human type II collagen/polylactide scaffold (rhCo-PLA) in the repair of full-thickness cartilage lesions with autologous chondrocyte implantation technique (ACI). The forming repair tissue was compared to spontaneous healing (spontaneous) and repair with a commercial porcine type I/III collagen membrane (pCo). Domestic pigs (4-month-old, n = 20) were randomized into three study groups and a circular full-thickness chondral lesion with a diameter of 8 mm was created in the right medial femoral condyle. After 3 weeks, the chondral lesions were repaired with either rhCo-PLA or pCo together with autologous chondrocytes, or the lesion was only debrided and left untreated for spontaneous repair. The repair tissue was evaluated 4 months after the second operation. Hyaline cartilage formed most frequently in the rhCo-PLA treatment group. Biomechanically, there was a trend that both treatment groups resulted in better repair tissue than spontaneous healing. Adverse subchondral bone reactions developed less frequently in the spontaneous group (40%) and the rhCo-PLA treated group (50%) than in the pCo control group (100%). However, no statistically significant differences were found between the groups. The novel rhCo-PLA biomaterial showed promising results in this proof-of-concept study, but further studies will be needed in order to determine its effectiveness in articular cartilage repair. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:745-753, 2016. PMID:26573959

  13. Articular cartilage lesions of the knee. MRI of tibial condylar fractures

    International Nuclear Information System (INIS)

    Lesions of the articular cartilage are rarely observed in convensional radiography and CT, and may be one of the most important prognostic factors in assessing traumatic or degenerative disorders at the knee joints. To discuss the usefulness of MRI for detecting cartilage lesions, knees with tibial condylar fractures were examined with MRI. 47 patients with tibial condylar fractures were reviewed 4 months to 15 years (average of 4 years) after the fractures. Good to excellent results were obtained in 91.5% of them. It is known that anatomical reduction of conventional radiography is not consistent with the clinical outcome, because radiography can show the changes of bones only. However, the results of MRI examinations are consistent with the clinical outcome, because they can directly show the state of the articular surface, such as defects of cartilage in the joint. In my study, no abnormality of well repaired joint surfaces employing MRI were observed in the patients with excellent or good results, and various degrees of cartilage lesions were detected using MRI in the other patients. MRI is a useful method for noninvasively determining the integrity of articular cartilage, detecting cartilage lesions and degenerative disorders of tibial condyle, and also may be useful in studying and following the natural aging process in osteoarthritis following intra-articular fractures. (author) 52 refs

  14. Noncontact evaluation of articular cartilage degeneration using a novel ultrasound water jet indentation system.

    Science.gov (United States)

    Lu, M-H; Zheng, Y P; Huang, Q-H; Ling, C; Wang, Q; Bridal, L; Qin, L; Mak, A

    2009-01-01

    We previously reported a noncontact ultrasound water jet indentation system for measuring and mapping tissue mechanical properties. The key idea was to utilize a water jet as an indenter as well as the coupling medium for high-frequency ultrasound. In this paper, the system was employed to assess articular cartilage degeneration, using stiffness ratio as an indicator of the mechanical properties of samples. Both the mechanical and acoustical properties of intact and degenerated bovine patellar articular cartilage (n = 8) were obtained in situ. It was found that the stiffness ratio was reduced by 44 +/- 17% after the articular cartilage was treated by 0.25% trypsin at 37 degrees C for 4 h while no significant difference in thickness was observed between the intact and degenerated samples. A significant decrease of 36 +/- 20% in the peak-to-peak amplitude of ultrasound echoes reflected from the cartilage surface was also found for the cartilage samples treated by trypsin. The results also showed that the stiffness obtained with the new method highly correlated with that measured using a standard mechanical testing protocol. A good reproducibility of the measurements was demonstrated. The present results showed that the ultrasound water jet indentation system may provide a potential tool for the non-destructive evaluation of articular cartilage degeneration by simultaneously obtaining mechanical properties, acoustical properties, and thickness data. PMID:19011965

  15. Repair of articular cartilage defects in minipigs by microfracture surgery and BMSCs transplantation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective: To investigate the feasibility of minimal invasive repair of cartilage defect by arthroscope-aided microfracture surgery and autologous transplantation of mesenchymal stem cells. Methods: Bone marrow of minipigs was taken out and the bone marrow derived mesenchymal stem cells (BMSCs) were isolated and cultured to passage 3. Then 6 minipigs were randomly divided into 2 groups with 6 knees in each group. After the articular cartilage defect was induced in each knee. the left defect received microfracture surgery and was injected with 2. 5 ml BMSCs cells at a concentration of 3×107 cells/ml into the articular cavity; while right knee got single microfracture or served as blank control group. The animals were killed at 8 or 16 weeks, and the repair tissue was histologically and immunohistochemically examined for the presence of type Ⅱ collagen and glycosaminoglycans (GAGs) at 8 and 16 weeks. Results:Eight weeks after the surgery, the overlying articular surface of the cartilage defect showed normal color and integrated to adjacent cartilage. And 16 weeks after surgery, hyaline cartilage was observed at the repairing tissues and immunostaining indicated the diffuse presence of this type Ⅱ collagen and GAGs throughout the repair cartilage in the treated defects. Single microfracture group had the repairing of fibro-cartilage, while during the treatment, the defects of blank group were covered with fewer fiber tissues, and no blood capillary growth or any immunological rejection was observed. Conclusion:Microfracture technique and BMSCs transplantation to repair cartilage defect is characterized with minimal invasion and easy operation, and it will greatly promote the regeneration repair of articular cartilage defect.

  16. Magnetic resonance imaging of articular cartilage abnormalities of the far posterior femoral condyle of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Ogino, Shuhei; Huang, Thomas; Watanabe, Atsuya; Iranpour-Boroujeni, Tannaz; Yoshioka, Hiroshi (Dept. of Radiology, Brigham and Women' s Hospital, Boston, MA (United States)), e-mail: hiroshi@uci.edu

    2010-01-15

    Background: Incidental articular cartilage lesions of the far posterior femoral condyle (FPFC) are commonly detected. Whether or not these cartilage lesions are symptomatic or clinically significant is unknown. Purpose: To characterize and assess prevalence of articular cartilage abnormalities of the FPFC and associated bone marrow edema (BME) and/or internal derangements through magnetic resonance (MR) images. Material and Methods: 654 knee MR examinations were reviewed retrospectively. Sagittal fast spin-echo proton density-weighted images with and without fat suppression were acquired with a 1.5T scanner, and were evaluated by two readers by consensus. The following factors were assessed: 1) the prevalence of cartilage abnormalities, 2) laterality, 3) the type of cartilage abnormalities, 4) cartilage abnormality grading, 5) associated BME, 6) complications such as meniscal injury and cruciate ligament injury, and 7) knee alignment (femorotibial angle [FTA]). Results: Articular cartilage abnormalities of the FPFC were demonstrated in 157 of the 654 patients (24%). Of these, 40 patients demonstrated medial and lateral FPFC cartilage abnormalities and were thus counted as 80 cases. Focal lateral FPFC abnormalities were demonstrated in 117 of 197 cases (59.4%), while diffuse lateral FPFC abnormalities were demonstrated in 24 of 197 cases (12.2%). Focal medial FPFC abnormalities were demonstrated in 23 of 197 cases (11.6%), while diffuse medial FPFC abnormalities were demonstrated in 33 of 197 cases (16.8%). No statistically significant pattern of associated BME, FTA, or internal derangements including meniscal and cruciate ligament injury was demonstrated. Conclusion: Articular cartilage abnormalities of the FPFC are common and were demonstrated in 24% of patients or 30% of cases. Lateral FPFC abnormalities occur 2.5 times more frequently than medial FPFC abnormalities and were more frequently focal compared with medial cohorts. BME is associated in 36.5% of cases

  17. Development of a Valid and Reliable Knee Articular Cartilage Condition–Specific Study Methodological Quality Score

    OpenAIRE

    Joshua D Harris; Erickson, Brandon J.; Cvetanovich, Gregory L.; Abrams, Geoffrey D.; McCormick, Frank M.; Gupta, Anil K.; Nikhil N. Verma; Bach, Bernard R.; Cole, Brian J.

    2014-01-01

    Background: Condition-specific questionnaires are important components in evaluation of outcomes of surgical interventions. No condition-specific study methodological quality questionnaire exists for evaluation of outcomes of articular cartilage surgery in the knee. Purpose: To develop a reliable and valid knee articular cartilage–specific study methodological quality questionnaire. Study Design: Cross-sectional study. Methods: A stepwise, a priori–designed framework was created for developme...

  18. [Basophilic line of the articular cartilage in normal and various pathological states].

    Science.gov (United States)

    Gongadze, L R

    1987-04-01

    Epiphyses of long tubular bones in the man and animals of various age, as well as experimental material of the adjuvant arthritis, with special reference to the basal part of the articular cartilage have been studied by means of histological, histochemical and histometrical methods. The structural-chemical organization of the basophilic line (tidemark) of the articular cartilage ensures its barrier role and participation in regulating selective permeability. Reconstruction of the tidemark in the process of physiological ageing and in cases of the articular pathology is aimed to preserve its integrity and in this way a complete differentiation of the noncalcified and calcified structures is secured. Disturbance of the basophilic line results in changes of the articular selective permeability, in invasion of vessels and structural elements of the bone marrow, and in development of profound distrophic and destructive changes of the cartilage--in deforming artrosis. Deflations in the structural-chemical organization of the tidemark indicate certain disturbances in the state of the system articular cartilage--subchondral bone. These data can be of prognostic importance. PMID:3606408

  19. Mitogenic and metabolic actions of epidermal growth factor on rat articular chondrocytes: modulation by fetal calf serum, transforming growth factor-beta, and tyrphostin.

    Science.gov (United States)

    Ribault, D; Khatib, A M; Panasyuk, A; Barbara, A; Bouizar, Z; Mitrovic, R D

    1997-01-15

    The effects of human recombinant epidermal growth factor (EGF) on rat articular chondrocytes from humeral and femoral head cartilage of 21-day-old Wistar rats were analyzed. The cells were cultured under standard conditions as monolayers. Cell proliferation was studied by [3H]thymidine incorporation and determination of DNA content, proteoglycan synthesis by [35S]sulfate incorporation, and collagen synthesis by [3H]proline incorporation. The presence of specific receptors was confirmed by [125I]-EGF binding and that of EGF and EGF-receptor (EGF-R) mRNA by reverse transcription and the polymerase chain reaction. EGF (0.5-2.5 ng/ml) stimulated [3H]thymidine incorporation and increased DNA content of cultures. The effect was strongest when serum concentration was low ( or =7.5%) serum concentrations. The EGF-induced effect on deoxynucleic acid synthesis was inhibited by transforming growth factor-beta and tyrphostin, a tyrosine kinase inhibitor that blocks the phosphorylation of tyrosine residues on EGF-R. Cultured rat articular chondrocytes possess a single class of high-affinity binding sites (Kd 0.18 nM). There were about 4.5 x 10(9) binding sites per microgram of DNA or about 37,800 binding sites per cell with 8.3 pg DNA per cell. Cultured cells contained EGF mRNA and EGF-R mRNA. Incubation of cells with EGF for 24 h decreased the EGF mRNA transcripts and increased the EGF-R mRNA levels. These findings suggest that EGF probably takes part in the regulation of chondrocyte activity under normal and presumably pathological conditions. PMID:9016808

  20. Tissue engineering for articular cartilage repair – the state of the art

    OpenAIRE

    Johnstone, B.; Alini, M.; M Cucchiarini; GR Dodge; Eglin, D.; F Guilak; Madry, H.; Mata, A.; RL Mauck; CE Semino; MJ Stoddart

    2013-01-01

    Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the cu...

  1. Alterations in periarticular bone and cross talk between subchondral bone and articular cartilage in osteoarthritis

    OpenAIRE

    Goldring, Steven R.

    2012-01-01

    The articular cartilage and the subchondral bone form a biocomposite that is uniquely adapted to the transfer of loads across the diarthrodial joint. During the evolution of the osteoarthritic process biomechanical and biological processes result in alterations in the composition, structure and functional properties of these tissues. Given the intimate contact between the cartilage and bone, alterations of either tissue will modulate the properties and function of the other joint component. T...

  2. Original Functional Rehabilitation Programme Based on Healing Physiology After Reconstruction of Articular Cartilage in Knee Joint

    OpenAIRE

    Guliyan, Volodymyr; Plenzler, Marcin; Straszewski, Dariusz; Paśnik, Marcin; Korbolewska, Olga; Suszczyński, Wojciech; Śmigielski, Robert

    2014-01-01

    Objectives: The evaluation of the quality of articular cartilage remodelling by means of arthroscopy findings and MRI imaging in a patient, who completed the original rehabilitation program. Methods: The rehabilitation program was conducted according to the Carolina Medical Center rehabilitation protocol. The patient was a 46 years old woman with fourth-degree cartilage damage (Outerbridge classification) located on the right medial femoral condyle of the following size: 1.5x2cm and 1x1.5cm. ...

  3. Collagen metabolism of human osteoarthritic articular cartilage as modulated by bovine collagen hydrolysates

    OpenAIRE

    Saskia Schadow; Hans-Christian Siebert; Günter Lochnit; Jens Kordelle; Markus Rickert; Jürgen Steinmeyer

    2013-01-01

    Destruction of articular cartilage is a characteristic feature of osteoarthritis (OA). Collagen hydrolysates are mixtures of collagen peptides and have gained huge public attention as nutriceuticals used for prophylaxis of OA. Here, we evaluated for the first time whether different bovine collagen hydrolysate preparations indeed modulate the metabolism of collagen and proteoglycans from human OA cartilage explants and determined the chemical composition of oligopeptides representing collagen ...

  4. Pulsed CO2 laser for intra-articular cartilage vaporization and subchondral bone perforation in horses

    Science.gov (United States)

    Nixon, Alan J.; Roth, Jerry E.; Krook, Lennart P.

    1991-05-01

    A pulsed carbon dioxide laser was used to vaporize articular cartilage in four horses, and perforate the cartilage and subchondral bone in four horses. Both intercarpal joints were examined arthroscopically and either a 1 cm cartilage crater or a series of holes was created in the third carpal bone of one joint. The contralateral carpus served as a control. The horses were evaluated clinically for 8 weeks, euthanatized and the joints examined radiographically, grossly, and histologically. Pulsed carbon dioxide laser vaporized cartilage readily but penetrated bone poorly. Cartilage vaporization resulted in no greater swelling, heat, pain on flexion, lameness, or synovial fluid reaction than the sham procedure. Laser drilling resulted in a shallow, charred hole with a tenacious carbon residue, and in combination with the thermal damage to deeper bone, resulted in increased swelling, mild lameness and a low-grade, but persistent synovitis. Cartilage removal by laser vaporization resulted in rapid regrowth with fibrous and fibrovascular tissue and occasional regions of fibrocartilage at week 8. The subchondral bone, synovial membrane, and draining lymph nodes appeared essentially unaffected by the laser cartilage vaporization procedure. Conversely, carbon dioxide laser drilling of subchondral bone resulted in poor penetration, extensive areas of thermal necrosis of bone, and significant secondary damage to the apposing articular surface of the radial carpal bone. The carbon dioxide laser is a useful intraarticular instrument for removal of cartilage and has potential application in inaccessible regions of diarthrodial joints. It does not penetrate bone sufficiently to have application in subchondral drilling.

  5. Quantitative MRI Evaluation of Articular Cartilage Using T2 Mapping Following Hip Arthroscopy for Femoroacetabular Impingement

    Science.gov (United States)

    Mayer, Stephanie W.; Wagner, Naomi; Fields, Kara G.; Wentzel, Catherine; Burge, Alissa; Potter, Hollis G.; Lyman, Stephen; Kelly, Bryan T.

    2016-01-01

    Objectives: Cam-type femoroacetabular impingement (FAI) causes a shearing and delamination injury to the acetabular articular cartilage due to a mismatch between the size of the femoral head and the acetabulum. This mechanism is thought to lead to early osteoarthritis in this population. Cam decompression has been advocated to eliminate impingement, with the ultimate goal of halting the progression of articular cartilage delamination. Although outcomes following this procedure in the young adult population have been favorable at short and medium term follow up, it is not known whether the articular cartilage itself is protected from further injury by changing the biomechanics of the joint with decompression of the cam morphology. The purpose of this study is to compare the pre- and post-operative integrity of the acetabular articular cartilage using T2 mapping to determine if hip arthroscopy is protective of the articular cartilage at short- to medium term follow up. Methods: Males between 18 and 35 years of age who had pre-operative T2 mapping MRIs, underwent hip arthroscopy for cam or mixed-type FAI with an alpha angle greater than 50°, and had at least 2 year follow-up were identified. Post-operative MRIs were performed and T2 relaxation times in the transition zone and weight bearing articular cartilage in the anterosuperior acetabulum at deep and superficial chondral layers were recorded at nine points on three sagittal sequences on pre and post-operative MRIs. A paired t-test was used to compare T2 relaxation values between pre-operative and post-operative scans. Results: Eleven hips were evaluated. Mean age was 26.3 years (range 21 - 35). Mean follow up time to post-operative T2 mapping MRI was 2.6 years (range 2.4 - 2.7). The change in T2 relaxation time was not significantly different between pre- and post-operative MRI scans for any of the nine regions in the deep zone of the acetabular cartilage (p=0.065 - 0.969) or the superficial zone of the

  6. Diffusion and near-equilibrium distribution of MRI and CT contrast agents in articular cartilage

    International Nuclear Information System (INIS)

    Charged contrast agents have been used both in vitro and in vivo for estimation of the fixed charge density (FCD) in articular cartilage. In the present study, the effects of molecular size and charge on the diffusion and equilibrium distribution of several magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents were investigated. Full thickness cartilage disks (Oe = 4.0 mm, n = 64) were prepared from fresh bovine patellae. Contrast agent (gadopentetate: Magnevist (registered) , gadodiamide: Omniscan(TM), ioxaglate: Hexabrix(TM) or sodium iodide: NaI) diffusion was allowed either through the articular surface or through the deep cartilage. CT imaging of the samples was conducted before contrast agent administration and after 1, 5, 9, 16, 25 and 29 h (and with three samples after 2, 3, 4 and 5 days) diffusion using a clinical peripheral quantitative computed tomography (pQCT) instrument. With all contrast agents, the diffusion through the deep cartilage was slower when compared to the diffusion through the articular surface. With ioxaglate, gadopentetate and gadodiamide it took over 29 h for diffusion to reach the near-equilibrium state. The slow diffusion of the contrast agents raise concerns regarding the validity of techniques for FCD estimation, as these contrast agents may not reach the equilibrium state that is assumed. However, since cartilage composition, i.e. deep versus superficial, had a significant effect on diffusion, imaging of the nonequilibrium diffusion process might enable more accurate assessment of cartilage integrity.

  7. Diffusion and near-equilibrium distribution of MRI and CT contrast agents in articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Silvast, Tuomo S; Toeyraes, Juha [Department of Clinical Neurophysiology, Kuopio University Hospital, PO Box 1777, 70211 Kuopio (Finland); Kokkonen, Harri T; Jurvelin, Jukka S [Department of Physics, University of Kuopio, PO Box 1627, 70211 Kuopio (Finland); Quinn, Thomas M [Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, Quebec H3A 2B2 (Canada); Nieminen, Miika T [Department of Diagnostic Radiology, Oulu University Hospital, PO Box 50, 90029, Oulu (Finland)], E-mail: Tuomo.Silvast@uku.fi

    2009-11-21

    Charged contrast agents have been used both in vitro and in vivo for estimation of the fixed charge density (FCD) in articular cartilage. In the present study, the effects of molecular size and charge on the diffusion and equilibrium distribution of several magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents were investigated. Full thickness cartilage disks (Oe = 4.0 mm, n = 64) were prepared from fresh bovine patellae. Contrast agent (gadopentetate: Magnevist (registered) , gadodiamide: Omniscan(TM), ioxaglate: Hexabrix(TM) or sodium iodide: NaI) diffusion was allowed either through the articular surface or through the deep cartilage. CT imaging of the samples was conducted before contrast agent administration and after 1, 5, 9, 16, 25 and 29 h (and with three samples after 2, 3, 4 and 5 days) diffusion using a clinical peripheral quantitative computed tomography (pQCT) instrument. With all contrast agents, the diffusion through the deep cartilage was slower when compared to the diffusion through the articular surface. With ioxaglate, gadopentetate and gadodiamide it took over 29 h for diffusion to reach the near-equilibrium state. The slow diffusion of the contrast agents raise concerns regarding the validity of techniques for FCD estimation, as these contrast agents may not reach the equilibrium state that is assumed. However, since cartilage composition, i.e. deep versus superficial, had a significant effect on diffusion, imaging of the nonequilibrium diffusion process might enable more accurate assessment of cartilage integrity.

  8. Diffusion and near-equilibrium distribution of MRI and CT contrast agents in articular cartilage.

    Science.gov (United States)

    Silvast, Tuomo S; Kokkonen, Harri T; Jurvelin, Jukka S; Quinn, Thomas M; Nieminen, Miika T; Töyräs, Juha

    2009-11-21

    Charged contrast agents have been used both in vitro and in vivo for estimation of the fixed charge density (FCD) in articular cartilage. In the present study, the effects of molecular size and charge on the diffusion and equilibrium distribution of several magnetic resonance imaging (MRI) and computed tomography (CT) contrast agents were investigated. Full thickness cartilage disks (Ø = 4.0 mm, n = 64) were prepared from fresh bovine patellae. Contrast agent (gadopentetate: Magnevist((R)), gadodiamide: Omniscan, ioxaglate: Hexabrix or sodium iodide: NaI) diffusion was allowed either through the articular surface or through the deep cartilage. CT imaging of the samples was conducted before contrast agent administration and after 1, 5, 9, 16, 25 and 29 h (and with three samples after 2, 3, 4 and 5 days) diffusion using a clinical peripheral quantitative computed tomography (pQCT) instrument. With all contrast agents, the diffusion through the deep cartilage was slower when compared to the diffusion through the articular surface. With ioxaglate, gadopentetate and gadodiamide it took over 29 h for diffusion to reach the near-equilibrium state. The slow diffusion of the contrast agents raise concerns regarding the validity of techniques for FCD estimation, as these contrast agents may not reach the equilibrium state that is assumed. However, since cartilage composition, i.e. deep versus superficial, had a significant effect on diffusion, imaging of the nonequilibrium diffusion process might enable more accurate assessment of cartilage integrity. PMID:19864699

  9. Cartilage Engineering and Microgravity

    Science.gov (United States)

    Toffanin, R.; Bader, A.; Cogoli, A.; Carda, C.; Fantazzini, P.; Garrido, L.; Gomez, S.; Hall, L.; Martin, I.; Murano, E.; Poncelet, D.; Pörtner, R.; Hoffmann, F.; Roekaerts, D.; Ronney, P.; Triebel, W.; Tummers, M.

    2005-06-01

    The complex effects of mechanical forces and growth factors on articular cartilage development still need to be investigated in order to identify optimal conditions for articular cartilage repair. Strictly controlled in vitro studies under modelled or space microgravity conditions can improve our understanding of the fundamental role of gravity in articular cartilage development. The main objective of this Topical Team is to use modelled microgravity as a tool to elucidate the fundamental science of cartilage regeneration. Particular attention is, therefore, given to the effects of physical forces under altered gravitational conditions, applied using controlled bioreactor systems, on cell metabolism, cell differentiation and tissue development. Specific attention is also directed toward the potential advantages of using magnetic resonance methods for the non-destructive characterisation of scaffolds, chondrocytes-polymer constructs and tissue engineered cartilage.

  10. Primary cilia attenuate hedgehog signalling in neoplastic chondrocytes

    OpenAIRE

    Ho, L.; Ali, S A; Al-Jazrawe, M; R. Kandel; Wunder, J S; Alman, B. A.

    2012-01-01

    Primary cilia can act as either a negative or positive regulator of the hedgehog (Hh) signaling pathway. Many cartilage tumors are characterized by abnormal activation of the Hh pathway. Here, we report that the presence of primary cilia occurs at a low frequency (12.4%) in neoplastic chondrocytes from malignant human chondrosarcomas, compared with chondrocytes from normal articular cartilage (67.7%). To determine the function of primary cilia in cartilaginous neoplasia, we studied benign car...

  11. SHP2-Deficiency in Chondrocytes Deforms Orofacial Cartilage and Ciliogenesis in Mice.

    Science.gov (United States)

    Kamiya, Nobuhiro; Shen, Jingling; Noda, Kazuo; Kitami, Megumi; Feng, Gen-Sheng; Chen, Di; Komatsu, Yoshihiro

    2015-11-01

    Congenital orofacial abnormalities are clinically seen in human syndromes with SHP2 germline mutations such as LEOPARD and Noonan syndrome. Recent studies demonstrate that SHP2-deficiency leads to skeletal abnormalities including scoliosis and cartilaginous benign tumor metachondromatosis, suggesting that growth plate cartilage is a key tissue regulated by SHP2. The role and cellular mechanism of SHP2 in the orofacial cartilage, however, remains unknown. Here, we investigated the postnatal craniofacial development by inducible disruption of Shp2 in chondrocytes. Shp2 conditional knockout (cKO) mice displayed severe deformity of the mandibular condyle accompanied by disorganized, expanded cartilage in the trabecular bone region, enhanced type X collagen, and reduced Erk production. Interestingly, the length of primary cilia, an antenna like organelle sensing environmental signaling, was significantly shortened, and the number of primary cilia was reduced in the cKO mice. The expression levels of intraflagellar transports (IFTs), essential molecules in the assembly and function of primary cilia, were significantly decreased. Taken together, lack of Shp2 in orofacial cartilage led to severe defects of ciliogenesis through IFT reduction, resulting in mandibular condyle malformation and cartilaginous expansion. Our study provides new insights into the molecular pathogenesis of SHP2-deficiency in cartilage and helps to understand orofacial and skeletal manifestations seen in patients with SHP2 mutations. PMID:25919282

  12. Topographical mapping of biochemical properties of articular cartilage in the equine fetlock joint

    NARCIS (Netherlands)

    Brama, P.A.J.; Tekoppele, J.M.; Bank, R.A.; Karssenberg, D.; Barneveld, A.; Weeren, P.R. van

    2000-01-01

    The aim of this study was to evaluate topographical differences in the biochemical composition of the extracellular matrix of articular cartilage of the normal equine fetlock joint. Water content, DNA content, glycosaminoglycan (GAG) content and a number of characteristics of the collagen network (t

  13. Glucosamine:chondroitin or ginger root extract have little effect on articular cartilage in swine

    Science.gov (United States)

    Sows are culled at a high rate from breeding herds due to musclo-skeletal problems and lameness. Research in our laboratory has shown that even first-parity sows have significant amounts of osteochondritic lesions of their articular cartilage. Glusoamine chondroitin and ginger root extract have both...

  14. Cycloolefin-Copolymer/Polyethylene (COC/PE) Blend Assists with the Creation of New Articular Cartilage

    Czech Academy of Sciences Publication Activity Database

    Petrtýl, M.; Bastl, Zdeněk; Kruliš, Zdeněk; Hulejová, H.; Polanská, M.; Lísal, J.; Danešová, J.; Černý, P.

    294-I, - (2010), s. 120-132. ISSN 1022-1360 R&D Projects: GA ČR GA106/06/0761 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40500505 Keywords : articular cartilage * biomaterials * cycloolefin-copolymer blend Subject RIV: CF - Physical ; Theoretical Chemistry

  15. Botanical Extracts from Rosehip (Rosa canina, Willow Bark (Salix alba, and Nettle Leaf (Urtica dioica Suppress IL-1β-Induced NF-κB Activation in Canine Articular Chondrocytes

    Directory of Open Access Journals (Sweden)

    Mehdi Shakibaei

    2012-01-01

    Full Text Available The aim of this study was to characterize the anti-inflammatory mode of action of botanical extracts from rosehip (Rosa canina, willow bark (Salix alba, and nettle leaf (Urtica dioica in an in vitro model of primary canine articular chondrocytes. Methods. The biological effects of the botanical extracts were studied in chondrocytes treated with IL-1β for up to 72 h. Expression of collagen type II, cartilage-specific proteoglycan (CSPG, β1-integrin, SOX-9, COX-2, and MMP-9 and MMP-13 was examined by western blotting. Results. The botanical extracts suppressed IL-1β-induced NF-κB activation by inhibition of IκBα phosphorylation, IκBα degradation, p65 phosphorylation, and p65 nuclear translocation. These events correlated with downregulation of NF-κB targets including COX-2 and MMPs. The extracts also reversed the IL-1β-induced downregulation of collagen type II, CSPG, β1-integrin, and cartilage-specific transcription factor SOX-9 protein expression. In high-density cultures botanical extracts stimulated new cartilage formation even in the presence of IL-1β. Conclusions. Botanical extracts exerted anti-inflammatory and anabolic effects on chondrocytes. The observed reduction of IL-1β-induced NF-κB activation suggests that further studies are warranted to demonstrate the effectiveness of plant extracts in the treatment of OA and other conditions in which NF-κB plays pathophysiological roles.

  16. Electrospun gelatin/polycaprolactone nanofibrous membranes combined with a coculture of bone marrow stromal cells and chondrocytes for cartilage engineering

    Directory of Open Access Journals (Sweden)

    He X

    2015-03-01

    Full Text Available Xiaomin He,1,* Bei Feng,1,2,* Chuanpei Huang,1 Hao Wang,1 Yang Ge,1 Renjie Hu,1 Meng Yin,1 Zhiwei Xu,1 Wei Wang,1 Wei Fu,1,2 Jinghao Zheng1 1Department of Pediatric Cardiothoracic Surgery, 2Institute of Pediatric Translational Medicine, Shanghai Children’s Medical Center School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Electrospinning has recently received considerable attention, showing notable potential as a novel method of scaffold fabrication for cartilage engineering. The aim of this study was to use a coculture strategy of chondrocytes combined with electrospun gelatin/polycaprolactone (GT/PCL membranes, instead of pure chondrocytes, to evaluate the formation of cartilaginous tissue. We prepared the GT/PCL membranes, seeded bone marrow stromal cell (BMSC/chondrocyte cocultures (75% BMSCs and 25% chondrocytes in a sandwich model in vitro, and then implanted the constructs subcutaneously into nude mice for 12 weeks. Gross observation, histological and immunohistological evaluation, glycosaminoglycan analyses, Young’s modulus measurement, and immunofluorescence staining were performed postimplantation. We found that the coculture group formed mature cartilage-like tissue, with no statistically significant difference from the chondrocyte group, and labeled BMSCs could differentiate into chondrocyte-like cells under the chondrogenic niche of chondrocytes. This entire strategy indicates that GT/PCL membranes are also a suitable scaffold for stem cell-based cartilage engineering and may provide a potentially clinically feasible approach for cartilage repairs. Keywords: electrospinning, nanocomposite, cartilage tissue engineering, nanomaterials, stem cells

  17. T2* mapping of articular cartilage: current status of research and first clinical applications.

    Science.gov (United States)

    Andreisek, Gustav; Weiger, Markus

    2014-01-01

    T2* mapping is a relatively new method for the compositional assessment of the articular cartilage. Typically, a multigradient echo or an ultrashort echo time imaging technique with a range of short and very short echo times is used. In most studies, imaging is performed at a high field strength, that is, 3 and 7 T. Postprocessing includes exponential fitting of relaxation decay and manual region-of-interest-based measurements of T2* times on T2* maps. Detailed analyses of T2* times of articular cartilage have shown distinct T2* components with shorter and longer T2* times. Moreover, there is a zonal distribution with a significant depthwise gradient of T2*, with relatively short times near the osteochondral junction and relatively long times at the cartilage's surface. T2* times of normal articular cartilage at the knee are, when averaged over the whole cartilage thickness and using monoexponential fitting, approximately 20 milliseconds. The results of recent studies have shown a good test-retest as well as interreader and intrareader reliabilities for T2* mapping. This article provides a descriptive review of the current literature, briefly discusses the technique itself, and provides an outlook on future research questions and possible clinical applications. PMID:24056113

  18. Effects of low-intensity pulsed ultrasound in repairing injured articular cartilage

    Institute of Scientific and Technical Information of China (English)

    JIA Xiao-lin; CHEN Wen-zhi; ZHOU Kun; WANG Zhi-biao

    2005-01-01

    Objective: To investigate the effects of low-intensity pulsed ultrasound in repairing injured articular cartilage. Methods: Ten adult New Zealand rabbits with bilateral full-thickness osteochondral defects on the cartilage surface of intercondylar fossas were used in this study. The wounds in the left knees were treated with low-intensity pulsed ultrasound as the experimental group. The right knees received no treatment as the control group. All the animals were killed at 8 weeks after injury and the tissues in the wounds were collected for gross appearance grading, histological grading and proteoglycan quantity. Results: The scores of the gross appearance grades, histological grades and the optical density of toluidine blue of the tissues in the experimental group were significantly higher than those of the controls at 8 weeks after injury (P<0.05). Conclusions: Low-intensity pulsed ultrasound can accelerate the repair of injured articular cartilage.

  19. Microstructure of Temporomandibular Joint Cartilage after Intra-Articular Betamethasone Sodium Phosphate/Betamethasone Dipropionate Injection during the Early Stage of Experimental Osteoarthrosis

    Directory of Open Access Journals (Sweden)

    Irina N. Kostina

    2014-06-01

    Full Text Available Objective: to study the morphological changes in cartilage after a single intra-articular betamethasone sodium phosphate (BSP/betamethasone dipropionate (BDP injection during the early stage of experimental osteoarthrosis (OA of the temporomandibular joint (TMJ. Material and Methods: The experiment was performed on 18 male rabbits aged 6 months .The first group consisted of 9 healthy rabbits. The second group included 9 rabbits with mechanically induced TMJ OA. For 5 days, 3 hours daily, a load (with a force of 200N on the TMJ was imposed. In the left TMJ of the second group of rabbits, betamethasone was injected intra-articularly in different doses: 0.1 ml (n=3, 0.3 ml (n=3, and 0.5 ml (n=3. The right TMJ was used for comparison. A combined anesthesia was applied each experimental day. Rabbits of both groups were sacrificed on days 7, 14, and 30 with introductory combined anesthesia and intravenous injection of Zoletil 100® 20 mg/kg to stop their breathing. Results: Betamethasone caused destruction of the chondrocytes, fragmentation of collagen fibers, deficit of proteoglycans (PGs and glycosaminoglycans (GAGs, thinning of the cartilage, and contributed to the progression of TMJ OA. Conclusion: The optimal dose of BSP/BDP for intra-articular injection in the early stages of TMJ OA must be within the range of 0.1-0.3 ml|0.7-1.5 mg.

  20. Fetal mesenchymal stromal cells differentiating towards chondrocytes acquire a gene expression profile resembling human growth plate cartilage.

    Directory of Open Access Journals (Sweden)

    Sandy A van Gool

    Full Text Available We used human fetal bone marrow-derived mesenchymal stromal cells (hfMSCs differentiating towards chondrocytes as an alternative model for the human growth plate (GP. Our aims were to study gene expression patterns associated with chondrogenic differentiation to assess whether chondrocytes derived from hfMSCs are a suitable model for studying the development and maturation of the GP. hfMSCs efficiently formed hyaline cartilage in a pellet culture in the presence of TGFβ3 and BMP6. Microarray and principal component analysis were applied to study gene expression profiles during chondrogenic differentiation. A set of 232 genes was found to correlate with in vitro cartilage formation. Several identified genes are known to be involved in cartilage formation and validate the robustness of the differentiating hfMSC model. KEGG pathway analysis using the 232 genes revealed 9 significant signaling pathways correlated with cartilage formation. To determine the progression of growth plate cartilage formation, we compared the gene expression profile of differentiating hfMSCs with previously established expression profiles of epiphyseal GP cartilage. As differentiation towards chondrocytes proceeds, hfMSCs gradually obtain a gene expression profile resembling epiphyseal GP cartilage. We visualized the differences in gene expression profiles as protein interaction clusters and identified many protein clusters that are activated during the early chondrogenic differentiation of hfMSCs showing the potential of this system to study GP development.

  1. Identification of stable normalization genes for quantitative real-time PCR in porcine articular cartilage

    Directory of Open Access Journals (Sweden)

    McCulloch Ryan S

    2012-11-01

    Full Text Available Abstract Background Expression levels for genes of interest must be normalized with an appropriate reference, or housekeeping gene, to make accurate comparisons of quantitative real-time PCR results. The purpose of this study was to identify the most stable housekeeping genes in porcine articular cartilage subjected to a mechanical injury from a panel of 10 candidate genes. Results Ten candidate housekeeping genes were evaluated in three different treatment groups of mechanically impacted porcine articular cartilage. The genes evaluated were: beta actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hydroxymethylbilane synthase, hypoxanthine phosphoribosyl transferase, peptidylprolyl isomerase A (cyclophilin A, ribosomal protein L4, succinate dehydrogenase flavoprotein subunit A, TATA box binding protein, and tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein—zeta polypeptide. The stability of the genes was measured using geNorm, BestKeeper, and NormFinder software. The four most stable genes measured via geNorm were (most to least stable succinate dehydrogenase flavoprotein, subunit A, peptidylprolyl isomerase A, glyceraldehyde-3-phosphate dehydrogenase, beta actin; the four most stable genes measured via BestKeeper were glyceraldehyde-3-phosphate dehydrogenase, peptidylprolyl isomerase A, beta actin, succinate dehydrogenase flavoprotein, subunit A; and the four most stable genes measured via NormFinder were peptidylprolyl isomerase A, succinate dehydrogenase flavoprotein, subunit A, glyceraldehyde-3-phosphate dehydrogenase, beta actin. Conclusions BestKeeper, geNorm, and NormFinder all generated similar results for the most stable genes in porcine articular cartilage. The use of these appropriate reference genes will facilitate accurate gene expression studies of porcine articular cartilage and suggest appropriate housekeeping genes for articular cartilage studies in other species.

  2. Now approaches to the treatment of articular cartilage lesions

    Directory of Open Access Journals (Sweden)

    M. Coviello

    2011-01-01

    Full Text Available Various approaches to the treatment of cartilage defects have been proposed in the literature; reparative and regenerative methods and, more recently, the Maioregen technique are currently available.

  3. Viscoelastic properties of bovine articular cartilage attached to subchondral bone at high frequencies

    Directory of Open Access Journals (Sweden)

    Shepherd Duncan ET

    2009-06-01

    Full Text Available Abstract Background Articular cartilage is a viscoelastic material, but its exact behaviour under the full range of physiological loading frequencies is unknown. The objective of this study was to measure the viscoelastic properties of bovine articular cartilage at loading frequencies of up to 92 Hz. Methods Intact tibial plateau cartilage, attached to subchondral bone, was investigated by dynamic mechanical analysis (DMA. A sinusoidally varying compressive force of between 16 N and 36 N, at frequencies from 1 Hz to 92 Hz, was applied to the cartilage surface by a flat indenter. The storage modulus, loss modulus and phase angle (between the applied force and the deformation induced were determined. Results The storage modulus, E', increased with increasing frequency, but at higher frequencies it tended towards a constant value. Its dependence on frequency, f, could be represented by, E' = Aloge (f + B where A = 2.5 ± 0.6 MPa and B = 50.1 ± 12.5 MPa (mean ± standard error. The values of the loss modulus (4.8 ± 1.0 MPa mean ± standard deviation were much less than the values of storage modulus and showed no dependence on frequency. The phase angle was found to be non-zero for all frequencies tested (4.9 ± 0.6°. Conclusion Articular cartilage is viscoelastic throughout the full range of frequencies investigated. The behaviour has implications for mechanical damage to articular cartilage and the onset of osteoarthritis. Storage modulus increases with frequency, until the plateau region is reached, and has a higher value than loss modulus. Furthermore, loss modulus does not increase with loading frequency. This means that more energy is stored by the tissue than is dissipated and that this effect is greater at higher frequencies. The main mechanism for this excess energy to be dissipated is by the formation of cracks.

  4. Hyaluronan Does Not Affect Bupivacaine’s Inhibitory Action on Voltage-Gated Potassium Channel Activities in Bovine Articular Chondrocytes

    OpenAIRE

    William Hester; Jinnan Yang; Guo-Yong Wang; Sen Liu; Michael J O'Brien; Savoie, Felix H.; Zongbing You

    2012-01-01

    Objectives. The objective of this paper is to determine if hyaluronan affects bupivacaine's anesthetic function. Methods. Whole cell patch clamp recordings were performed on bovine articular chondrocytes cultured in 60 mm dishes. The chondrocytes were treated with phosphate-buffered saline (control group), 7.5 mg/mL hyaluronan (Orthovisc), 0.25% bupivacaine, or a mixture of 7.5 mg/mL hyaluronan and 0.25% bupivacaine. Outward currents were elicited by step depolarization from −90 mV to 150 mV ...

  5. Looping Mediated Interaction between the Promoter and 3′ UTR Regulates Type II Collagen Expression in Chondrocytes

    OpenAIRE

    Jash, Arijita; Yun, Kangsun; Sahoo, Anupama; So, Jae-Seon; Im, Sin-Hyeog

    2012-01-01

    Type II collagen is the major component of articular cartilage and is mainly synthesized by chondrocytes. Repeated sub-culturing of primary chondrocytes leads to reduction of type II collagen gene (Col2a1) expression, which mimics the process of chondrocyte dedifferentiation. Although the functional importance of Col2a1 expression has been extensively investigated, mechanism of transcriptional regulation during chondrocyte dedifferentiation is still unclear. In this study, we have investigate...

  6. In vitro of quantitative MR imaging of early degenerative changes in human articular cartilage

    International Nuclear Information System (INIS)

    To assess the applicability of quantitative MR microscopy for the detection of glycosaminoglycan (GAG) depletion as an early sign of degeneration in the articular cartilage of humans treated by trypsin. Four cartilage-bone blocks were obtained from the patient who had suffered from osteoarthritis of the knee and underwent a total knee replacement arthroscopy. Each articular cartilage segment was resected as to a round disk shape (8 mm in diameter) with a remnant of subchondral bone 1 mm in thickness. Four different culture solutions were prepared, and these solutions were 0.2 mg/ml of trypsin solution (group 1), 1 mM of Gd (DTPA) 2-mixed trypsin solution (group 2), phosphate buffered saline (PBS) (group 3), and 1 mM of Gd (DTPA) 2-mixed PBS (group 4). The cartilages were cultured and then MR imagings were performed every hour for 5 hrs, and we continued the additional cultures of 24 hrs, 36 hrs and 48 hrs. Three imaging sequences were used: T1-weighted spin echo (TR/TE, 450/22), proton density turbo spin echo with fat suppression (TR/TE, 3000/25), and CPMG (Carr-Purcell-Meiboom-Gill) (TR/TE/TI, 760/21-168, 360). MR imaging data were analyzed with pixel-by-pixel comparisons in all groups. The GAG loss in the articular cartilage was increased proportionately to the culture duration. Mean changes of T1 relaxation time were 1.2% for group 1, -1.9% for group 3, -54.7% for group 2 and -64.2% for group 4 (p< 0.05). When comparing by linear profile on the T1-weighted images, SNR increased and T1 relaxation time decreased for group 2 and 4, as the culture duration increased (p< 0.05). On the correlation analysis, there is significant correlation between GAG loss and Gd (DTPA) 2-enhancement for group 2 (p=0.0431), but there was no significant difference for group 4 (p=0.0918). More enhancement with Gd (DTPA) 2-was noted for group 2 than for group 4. Group 2 showed a diffuse enhancement in all the layers of cartilage, but for group 4, prominent enhancement was noted only in

  7. Determining Tension-Compression Nonlinear Mechanical Properties of Articular Cartilage from Indentation Testing.

    Science.gov (United States)

    Chen, Xingyu; Zhou, Yilu; Wang, Liyun; Santare, Michael H; Wan, Leo Q; Lu, X Lucas

    2016-04-01

    The indentation test is widely used to determine the in situ biomechanical properties of articular cartilage. The mechanical parameters estimated from the test depend on the constitutive model adopted to analyze the data. Similar to most connective tissues, the solid matrix of cartilage displays different mechanical properties under tension and compression, termed tension-compression nonlinearity (TCN). In this study, cartilage was modeled as a porous elastic material with either a conewise linear elastic matrix with cubic symmetry or a solid matrix reinforced by a continuous fiber distribution. Both models are commonly used to describe the TCN of cartilage. The roles of each mechanical property in determining the indentation response of cartilage were identified by finite element simulation. Under constant loading, the equilibrium deformation of cartilage is mainly dependent on the compressive modulus, while the initial transient creep behavior is largely regulated by the tensile stiffness. More importantly, altering the permeability does not change the shape of the indentation creep curves, but introduces a parallel shift along the horizontal direction on a logarithmic time scale. Based on these findings, a highly efficient curve-fitting algorithm was designed, which can uniquely determine the three major mechanical properties of cartilage (compressive modulus, tensile modulus, and permeability) from a single indentation test. The new technique was tested on adult bovine knee cartilage and compared with results from the classic biphasic linear elastic curve-fitting program. PMID:26240062

  8. A biphasic finite element study on the role of the articular cartilage superficial zone in confined compression.

    Science.gov (United States)

    Guo, Hongqiang; Maher, Suzanne A; Torzilli, Peter A

    2015-01-01

    The aim of this study was to investigate the role of the superficial zone on the mechanical behavior of articular cartilage. Confined compression of articular cartilage was modeled using a biphasic finite element analysis to calculate the one-dimensional deformation of the extracellular matrix (ECM) and movement of the interstitial fluid through the ECM and articular surface. The articular cartilage was modeled as an inhomogeneous, nonlinear hyperelastic biphasic material with depth and strain-dependent material properties. Two loading conditions were simulated, one where the superficial zone was loaded with a porous platen (normal test) and the other where the deep zone was loaded with the porous platen (upside down test). Compressing the intact articular cartilage with 0.2 MPa stress reduced the surface permeability by 88%. Removing the superficial zone increased the rate of change for all mechanical parameters and decreased the fluid support ratio of the tissue, resulting in increased tissue deformation. Apparent permeability linearly increased after superficial removal in the normal test, yet it did not change in the upside down test. Orientation of the specimen affected the time-dependent biomechanical behavior of the articular cartilage, but not equilibrium behavior. The two tests with different specimen orientations resulted in very different apparent permeabilities, suggesting that in an experimental study which quantifies material properties of an inhomogeneous material, the specimen orientation should be stated along with the permeability result. The current study provides new insights into the role of the superficial zone on mechanical behavior of the articular cartilage. PMID:25465194

  9. Cell expansion of human articular chondrocytes on macroporous gelatine scaffolds-impact of microcarrier selection on cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Sofia; Kratz, Gunnar [Laboratory for Reconstructive Plastic Surgery, Department of Clinical and Experimental Medicine, Linkoeping University, SE-581 85 Linkoeping (Sweden); Wetteroe, Jonas [Rheumatology/AIR, Department of Clinical and Experimental Medicine, Linkoeping University, SE-581 85 Linkoeping (Sweden); Tengvall, Pentti, E-mail: sofia.pettersson@liu.se [Institute of Clinical Sciences, Department of Biomaterials, The Sahlgrenska Academy at University of Gothenburg, SE-405 30 Gothenburg (Sweden)

    2011-12-15

    This study investigates human chondrocyte expansion on four macroporous gelatine microcarriers (CultiSpher) differing with respect to two manufacturing processes-the amount of emulsifier used during initial preparation and the gelatine cross-linking medium. Monolayer-expanded articular chondrocytes from three donors were seeded onto the microcarriers and cultured in spinner flask systems for a total of 15 days. Samples were extracted every other day to monitor cell viability and establish cell counts, which were analysed using analysis of variance and piecewise linear regression. Chondrocyte densities increased according to a linear pattern for all microcarriers, indicating an ongoing, though limited, cell proliferation. A strong chondrocyte donor effect was seen during the initial expansion phase. The final cell yield differed significantly between the microcarriers and our results indicate that manufacturing differences affected chondrocyte densities at this point. Remaining cells stained positive for chondrogenic markers SOX-9 and S-100 but extracellular matrix formation was modest to undetectable. In conclusion, the four gelatine microcarriers supported chondrocyte adhesion and proliferation over a two week period. The best yield was observed for microcarriers produced with low emulsifier content and cross-linked in water and acetone. These results add to the identification of optimal biomaterial parameters for specific cellular processes and populations.

  10. Effect of corticosteroids on articular cartilage: have animal studies said everything?

    Science.gov (United States)

    Vandeweerd, Jean-Michel; Zhao, Yang; Nisolle, Jean-François; Zhang, Wenhui; Zhihong, Liu; Clegg, Peter; Gustin, Pascal

    2015-10-01

    Intra-articular (IA) corticosteroids (CS) have been used in the treatment of osteoarthritis for many years, although their effects on articular cartilage are not fully understood. To identify whether previous animal studies have provided enough evidence about the effects of CS, we undertook a systematic review that identified 35 relevant in vivo animal experimental studies between 1965 and 2014 assessing the effects of CS on either normal cartilage, or in either induced osteoarthritis (OA) or synovitis. The quality of the methodology was assessed. Deleterious effects, both structural and biochemical, have mainly been reported in rabbits and are associated with frequent administration of CS, sometimes at high dose and with systemic side effects. In dogs, four identified studies concluded that there were beneficial effects with methylprednisolone acetate (MPA) and triamcinolone hexacetonide therapy. In horses, MPA was mostly deleterious, while triamcinolone acetonide had positive effects in one study highly rated at quality assessment. However, many methodological weaknesses have been identified, such as the lack of pharmacokinetic and pharmocodynamics data and the large variation in doses between studies, the limited selection criteria at baseline, the absence of blinding, and the lack of statistics or appropriate controls for testing the effects of the vehicle of the drug. Those methodological weaknesses weaken the conclusions of numerous studies that assess beneficial or deleterious effects of CS on articular cartilage. Animal studies have not yet provided definitive data, and further research is required into the role of CS in articular pathobiology. PMID:26211421

  11. Increasing lateral tibial slope: is there an association with articular cartilage changes in the knee?

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Nasir; Shepel, Michael; Leswick, David A.; Obaid, Haron [University of Saskatchewan, Department of Medical Imaging, Royal University Hospital, and College of Medicine, Saskatoon, Saskatchewan (Canada)

    2014-04-15

    The geometry of the lateral tibial slope (LTS) plays an important role in the overall biomechanics of the knee. Through this study, we aim to assess the impact of LTS on cartilage degeneration in the knee. A retrospective analysis of 93 knee MRI scans (1.5 T or 3 T) for patients aged 20-45 years with no history of trauma or knee surgery, and absence of internal derangement. The LTS was calculated using the circle method. Chondropathy was graded from 0 (normal) to 3 (severe). Linear regression analysis was used for statistical analysis (p < 0.05). In our cohort of patients, a statistically significant association was seen between increasing LTS and worsening cartilage degenerative changes in the medial patellar articular surface and the lateral tibial articular surface (p < 0.05). There was no statistically significant association between increasing LTS and worsening chondropathy of the lateral patellar, medial trochlea, lateral trochlea, medial femoral, lateral femoral, and medial tibial articular surfaces. Our results show a statistically significant association between increasing LTS and worsening cartilage degenerative changes in the medial patella and the lateral tibial plateau. We speculate that increased LTS may result in increased femoral glide over the lateral tibial plateau with subsequent increased external rotation of the femur predisposing to patellofemoral articular changes. Future arthroscopic studies are needed to further confirm our findings. (orig.)

  12. Increasing lateral tibial slope: is there an association with articular cartilage changes in the knee?

    International Nuclear Information System (INIS)

    The geometry of the lateral tibial slope (LTS) plays an important role in the overall biomechanics of the knee. Through this study, we aim to assess the impact of LTS on cartilage degeneration in the knee. A retrospective analysis of 93 knee MRI scans (1.5 T or 3 T) for patients aged 20-45 years with no history of trauma or knee surgery, and absence of internal derangement. The LTS was calculated using the circle method. Chondropathy was graded from 0 (normal) to 3 (severe). Linear regression analysis was used for statistical analysis (p < 0.05). In our cohort of patients, a statistically significant association was seen between increasing LTS and worsening cartilage degenerative changes in the medial patellar articular surface and the lateral tibial articular surface (p < 0.05). There was no statistically significant association between increasing LTS and worsening chondropathy of the lateral patellar, medial trochlea, lateral trochlea, medial femoral, lateral femoral, and medial tibial articular surfaces. Our results show a statistically significant association between increasing LTS and worsening cartilage degenerative changes in the medial patella and the lateral tibial plateau. We speculate that increased LTS may result in increased femoral glide over the lateral tibial plateau with subsequent increased external rotation of the femur predisposing to patellofemoral articular changes. Future arthroscopic studies are needed to further confirm our findings. (orig.)

  13. Experimental study of tissue-engineered cartilage allograft with RNAi chondrocytes in vivo

    Directory of Open Access Journals (Sweden)

    Wang ZH

    2014-05-01

    Full Text Available Zhenghui Wang,1 Xiaoli Li,2 Xi-Jing He,3 Xianghong Zhang,1 Zhuangqun Yang,4 Min Xu,1 Baojun Wu,1 Junbo Tu,5 Huanan Luo,1 Jing Yan11Department of Otolaryngology – Head and Neck Surgery, 2Department of Dermatology, 3Department of Orthopedics, The Second Hospital, Xi’an Jiaotong University, 4Department of Plastic and Burns Surgery, The First Hospital, Xi’an Jiaotong University, 5Department of Oral and Maxillofacial Plastic Surgery, The Stomatological Hospital, Xi’an Jiaotong University, Xi’an, People’s Republic of ChinaPurpose: To determine the effects of RNA interference (RNAi on chondrocyte proliferation, function, and immunological rejection after allogenic tissue-engineered cartilage transplantation within bone matrix gelatin scaffolds.Methods: Seven million rat normal and RNAi chondrocytes were harvested and separately composited with fibrin glue to make the cell suspension, and then transplanted subcutaneously into the back of Sprague Dawley rats after being cultured for 10 days in vitro. Untransplanted animals served as the control group. The allograft and immunological response were examined at 1, 2, 4, 8, and 12 months postoperatively with hematoxylin and eosin histochemical staining, immunohistochemical staining (aggrecan, type II collagen, class I and II major histocompatibility complex, and flow cytometry for peripheral blood cluster of differentiation 4+ (CD4+ and CD8+ T-cells.Results: There was no infection or death in the rats except one, which died in the first week. Compared to the control group, the RNAi group had fewer eukomonocytes infiltrated, which were only distributed around the graft. The ratio of CD4+/CD8+ T-cells in the RNAi group was significantly lower than the normal one (P<0.05. There were many more positively stained chondrocytes and positively stained areas around the cells in the RNAi group, which were not found in the control group.Conclusion: The aggrecanase-1 and aggrecanase-2 RNAi for chondrocytes

  14. Highly nonlinear stress-relaxation response of articular cartilage in indentation: Importance of collagen nonlinearity.

    Science.gov (United States)

    Mäkelä, J T A; Korhonen, R K

    2016-06-14

    Modern fibril-reinforced computational models of articular cartilage can include inhomogeneous tissue composition and structure, and nonlinear mechanical behavior of collagen, proteoglycans and fluid. These models can capture well experimental single step creep and stress-relaxation tests or measurements under small strains in unconfined and confined compression. Yet, it is known that in indentation, especially at high strain velocities, cartilage can express highly nonlinear response. Different fibril reinforced poroelastic and poroviscoelastic models were used to assess measured highly nonlinear stress-relaxation response of rabbit articular cartilage in indentation. Experimentally measured depth-dependent volume fractions of different tissue constituents and their mechanical nonlinearities were taken into account in the models. In particular, the collagen fibril network was modeled using eight separate models that implemented five different constitutive equations to describe the nonlinearity. These consisted of linear elastic, nonlinear viscoelastic and multiple nonlinear elastic representations. The model incorporating the most nonlinearly increasing Young׳s modulus of collagen fibrils as a function of strain captured best the experimental data. Relative difference between the model and experiment was ~3%. Surprisingly, the difference in the peak forces between the experiment and the model with viscoelastic collagen fibrils was almost 20%. Implementation of the measured volume fractions did not improve the ability of the model to capture the measured mechanical data. These results suggest that a highly nonlinear formulation for collagen fibrils is needed to replicate multi-step stress-relaxation response of rabbit articular cartilage in indentation with high strain rates. PMID:27130474

  15. A Novel Model for the Mass Transfer of Articular Cartilage: Rolling Depression Load Device

    Science.gov (United States)

    Fan, Zhenmin; Zhang, Chunqiu; Liu, Haiying; Xu, Baoshan; Li, Jiang; Gao, Lilan

    The mass transfer is one of important aspects to maintain the physiological activity proper of tissue, specially, cartilage cannot run without mechanical environment. The mechanical condition drives nutrition in and waste out in the cartilage tissue, the change of this process plays a key role for biological activity. Researchers used to adopt compression to study the mass transfer in cartilage, here we firstly establish a new rolling depression load (RDL) device, and also put this device into practice. The device divided into rolling control system and the compression adjusting mechanism. The rolling control system makes sure the pure rolling and uniform speed of roller applying towards cultured tissue. The compression adjusting mechanism can realize different compressive magnitudes and uniform compression. Preliminary test showed that rolling depression load indeed enhances the process of mass transfer articular cartilage.

  16. Freeze-thaw treatment effects on the dynamic mechanical properties of articular cartilage

    Directory of Open Access Journals (Sweden)

    Muldrew Ken

    2010-10-01

    Full Text Available Abstract Background As a relatively non-regenerative tissue, articular cartilage has been targeted for cryopreservation as a method of mitigating a lack of donor tissue availability for transplant surgeries. In addition, subzero storage of articular cartilage has long been used in biomedical studies using various storage temperatures. The current investigation studies the potential for freeze-thaw to affect the mechanical properties of articular cartilage through direct comparison of various subzero storage temperatures. Methods Both subzero storage temperature as well as freezing rate were compared using control samples (4°C and samples stored at either -20°C or -80°C as well as samples first snap frozen in liquid nitrogen (-196°C prior to storage at -80°C. All samples were thawed at 37.5°C to testing temperature (22°C. Complex stiffness and hysteresis characterized load resistance and damping properties using a non-destructive, low force magnitude, dynamic indentation protocol spanning a broad loading rate range to identify the dynamic viscoelastic properties of cartilage. Results Stiffness levels remained unchanged with exposure to the various subzero temperatures. Hysteresis increased in samples snap frozen at -196°C and stored at -80°C, though remained unchanged with exposure to the other storage temperatures. Conclusions Mechanical changes shown are likely due to ice lens creation, where frost heave effects may have caused collagen damage. That storage to -20°C and -80°C did not alter the mechanical properties of articular cartilage shows that when combined with a rapid thawing protocol to 37.5°C, the tissue may successfully be stored at subzero temperatures.

  17. Evaluation using MRI T2 mapping of the articular cartilage after anterior cruciate ligament injury in young athletes

    International Nuclear Information System (INIS)

    Articular cartilage damage coexisting in the anterior cruciate ligament (ACL) injury in young athletes is not rare. We evaluated the conditions of the articular cartilage using MRI T2 mapping method and compared the vesults with the findings of arthroscopy. From June to August in 2010, we performed ACL reconstruction in 31 patients. We selected 17 cases (eleven men and six women, mean age 19.1 years old), all of whom were athletes and the under 29 years old. Articular cartilage damage was observed in six out of 10 cases, and their T2 values were high on MRI T2 mapping. On the other hand, damage was observed only in one out of seven cases, and T2 values were in the normal level of the mapping. Using MRI T2 mapping, we can evaluate the articular cartilage at an early phase noninvasively. MRI T2 mapping is useful and effective for athletes. (author)

  18. Effect of a Herbal-Leucine mix on the IL-1β-induced cartilage degradation and inflammatory gene expression in human chondrocytes

    Directory of Open Access Journals (Sweden)

    Haqqi Tariq M

    2011-08-01

    Full Text Available Abstract Background Conventional treatments for the articular diseases are often effective for symptom relief, but can also cause significant side effects and do not slow the progression of the disease. Several natural substances have been shown to be effective at relieving the symptoms of osteoarthritis (OA, and preliminary evidence suggests that some of these compounds may exert a favorable influence on the course of the disease. The objective of this study was to investigate the anti-inflammatory/chondroprotective potential of a Herbal and amino acid mixture containing extract of the Uncaria tomentosa, Boswellia spp., Lepidium meyenii and L-Leucine on the IL-1β-induced production of nitric oxide (NO, glycosaminoglycan (GAG, matrix metalloproteinases (MMPs, aggrecan (ACAN and type II collagen (COL2A1 in human OA chondrocytes and OA cartilage explants. Methods Primary OA chondrocytes or OA cartilage explants were pretreated with Herbal-Leucine mixture (HLM, 1-10 μg/ml and then stimulated with IL-1β (5 ng/ml. Effect of HLM on IL-1β-induced gene expression of iNOS, MMP-9, MMP-13, ACAN and COL2A1 was verified by real time-PCR. Estimation of NO and GAG release in culture supernatant was done using commercially available kits. Results HLM tested in these in vitro studies was found to be an effective anti-inflammatory agent, as evidenced by strong inhibition of iNOS, MMP-9 and MMP-13 expression and NO production in IL-1β-stimulated OA chondrocytes (p Leucine mixture (HLM up-regulation of ACAN and COL2A1 expression in IL-1β-stimulated OA chondrocytes was also noted (p Conclusion Our data suggests that HLM could be chondroprotective and anti-inflammatory agent in arthritis, switching chondrocyte gene expression from catabolic direction towards anabolic and regenerative, and consequently this approach may be potentially useful as a new adjunct therapeutic/preventive agent for OA or injury recovery.

  19. Activated platelet-rich plasma improves adipose-derived stem cell transplantation efficiency in injured articular cartilage

    OpenAIRE

    Pham, Phuc Van; Bui, Khanh Hong-Thien; Ngo, Dat Quoc; Vu, Ngoc Bich; Truong, Nhung Hai; Phan, Nhan Lu-Chinh; Le, Dung Minh; Duong, Triet Dinh; Nguyen, Thanh Duc; Le, Vien Tuong; Phan, Ngoc Kim

    2013-01-01

    Introduction Adipose-derived stem cells (ADSCs) have been isolated, expanded, and applied in the treatment of many diseases. ADSCs have also been used to treat injured articular cartilage. However, there is controversy regarding the treatment efficiency. We considered that ADSC transplantation with activated platelet-rich plasma (PRP) may improve injured articular cartilage compared with that of ADSC transplantation alone. In this study, we determined the role of PRP in ADSC transplantation t...

  20. The collagen structure of equine articular cartilage, characterized using polarization-sensitive optical coherence tomography

    Science.gov (United States)

    Ugryumova, Nadya; Attenburrow, Don P.; Winlove, C. Peter; Matcher, Stephen J.

    2005-08-01

    Optical coherence tomography and polarization-sensitive optical coherence tomography images of equine articular cartilage are presented. Measurements were made on intact joint surfaces. Significant (e.g. × 2) variations in the intrinsic birefringence were found over spatial scales of a few millimetres, even on samples taken from young (18 month) animals that appeared visually homogeneous. A comparison of data obtained on a control tissue (equine flexor tendon) further suggests that significant variations in the orientation of the collagen fibres relative to the plane of the joint surface exist. Images of visually damaged cartilage tissue show characteristic features both in terms of the distribution of optical scatterers and of the birefringent components.

  1. The collagen structure of equine articular cartilage, characterized using polarization-sensitive optical coherence tomography

    International Nuclear Information System (INIS)

    Optical coherence tomography and polarization-sensitive optical coherence tomography images of equine articular cartilage are presented. Measurements were made on intact joint surfaces. Significant (e.g. x 2) variations in the intrinsic birefringence were found over spatial scales of a few millimetres, even on samples taken from young (18 month) animals that appeared visually homogeneous. A comparison of data obtained on a control tissue (equine flexor tendon) further suggests that significant variations in the orientation of the collagen fibres relative to the plane of the joint surface exist. Images of visually damaged cartilage tissue show characteristic features both in terms of the distribution of optical scatterers and of the birefringent components

  2. T2* mapping for articular cartilage assessment: principles, current applications, and future prospects

    International Nuclear Information System (INIS)

    With advances in joint preservation surgery that are intended to alter the course of osteoarthritis by early intervention, accurate and reliable assessment of the cartilage status is critical. Biochemically sensitive MRI techniques can add robust biomarkers for disease onset and progression, and therefore, could be meaningful assessment tools for the diagnosis and follow-up of cartilage abnormalities. T2* mapping could be a good alternative because it would combine the benefits of biochemical cartilage evaluation with remarkable features including short imaging time and the ability of high-resolution three-dimensional cartilage evaluation - without the need for contrast media administration or special hardware. Several in vitro and in vivo studies, which have elaborated on the potential of cartilage T2* assessment in various cartilage disease patterns and grades of degeneration, have been reported. However, much remains to be understood and certain unresolved questions have become apparent with these studies that are crucial to the further application of this technique. This review summarizes the principles of the technique and current applications of T2* mapping for articular cartilage assessment. Limitations of recent studies are discussed and the potential implications for patient care are presented. (orig.)

  3. T2* mapping for articular cartilage assessment: principles, current applications, and future prospects

    Energy Technology Data Exchange (ETDEWEB)

    Hesper, Tobias; Bittersohl, Daniela; Krauspe, Ruediger; Zilkens, Christoph [University Duesseldorf, Department of Orthopaedics Medical Faculty, Duesseldorf (Germany); Hosalkar, Harish S. [Center of Hip Preservation and Children' s Orthopaedics, San Diego, CA (United States); Welsch, Goetz H. [Medical University of Vienna, MR Center, Department of Radiology, Vienna (Austria); Bittersohl, Bernd [University Duesseldorf, Department of Orthopaedics Medical Faculty, Duesseldorf (Germany); Heinrich-Heine University, Medical School, Department of Orthopaedics, Duesseldorf (Germany)

    2014-10-15

    With advances in joint preservation surgery that are intended to alter the course of osteoarthritis by early intervention, accurate and reliable assessment of the cartilage status is critical. Biochemically sensitive MRI techniques can add robust biomarkers for disease onset and progression, and therefore, could be meaningful assessment tools for the diagnosis and follow-up of cartilage abnormalities. T2* mapping could be a good alternative because it would combine the benefits of biochemical cartilage evaluation with remarkable features including short imaging time and the ability of high-resolution three-dimensional cartilage evaluation - without the need for contrast media administration or special hardware. Several in vitro and in vivo studies, which have elaborated on the potential of cartilage T2* assessment in various cartilage disease patterns and grades of degeneration, have been reported. However, much remains to be understood and certain unresolved questions have become apparent with these studies that are crucial to the further application of this technique. This review summarizes the principles of the technique and current applications of T2* mapping for articular cartilage assessment. Limitations of recent studies are discussed and the potential implications for patient care are presented. (orig.)

  4. Influence of Cartilage Extracellular Matrix Molecules on Cell Phenotype and Neocartilage Formation

    OpenAIRE

    Grogan, Shawn P.; Chen, Xian; Sovani, Sujata; Taniguchi, Noboru; Colwell, Clifford W.; Lotz, Martin K; D'Lima, Darryl D

    2013-01-01

    Interaction between chondrocytes and the cartilage extracellular matrix (ECM) is essential for maintaining the cartilage's role as a low-friction and load-bearing tissue. In this study, we examined the influence of cartilage zone-specific ECM on human articular chondrocytes (HAC) in two-dimensional and three-dimensional (3D) environments. Two culture systems were used. SYSTEM 1: HAC were cultured on cell-culture plates that had been precoated with the following ECM molecules for 7 days: decor...

  5. Effect of the disruption of three cytoskeleton components on chondrocyte metabolism in rabbit knee cartilage

    Institute of Scientific and Technical Information of China (English)

    Duan Wangping; Wei Lei; Cao Xiaoming; Guo Heng; Wang Lei; Hao Yongzhuang; Wei Xiaochun

    2014-01-01

    Background Chondrocytes' phenotype and biosynthesis of matrix are dependent on having an intact cytoskeletal structure.Microfilaments,microtubules,and intermediate filaments are three important components of the cytoskeletal structure of chondrocytes.The aims of this study were to determine and compare the effects of the disruption of these three cytoskeletal elements on the apoptosis and matrix synthesis by rabbit knee chondrocytes in vitro.Methods Chondrocytes were isolated from full-thickness knee cartilage of two-month-old rabbits using enzymatic methods (n=24).The isolated cells were stabilized for three days and then exposed to low,medium,and high doses of chemical agents that disrupt the three principal cytoskeletal elements of interest:colchicine for microtubules,acrylamide for intermediate filaments,and cytochalasin D for actin microfilaments.A group of control cells were treated with carrier.Early apoptosis was assessed using the Annexin-FITC binding assay by flow cytometry on days 1 and 2 after exposure to the disrupting chemical agents.The components and distribution of the cytoskeleton within the cells were analyzed by laser scanning confocal microscopy (LSCM) with immunofluorescence staining on day 3.The mRNA levels of aggrecan (AGG) and type Ⅱ collagen (Col-2) and their levels in culture medium were analyzed using real-time PCR and enzymelinked immunosorbent serologic assay (ELISA) on days 3,6,and 9.Results In the initial drug-dose-response study,there was no significant difference in the vitality of cells treated with 0.1 μmol/L colchicine,2.5 mmol/L acrylamide,and 10 μg/L cytochalasin D for two days when compared with the control group of cells.The concentrations of colchicine and acrylamide treatment selected above significantly decreased the number of viable cells over the nine-day culture and disrupted significantly more cell nuclei.Real-time PCR and ELISA results showed that the mRNA levels and medium concentrations of AGG and Col-2 were

  6. Hyaluronic Acid-Binding Scaffold for Articular Cartilage Repair

    OpenAIRE

    Unterman, Shimon A.; Gibson, Matthew; Lee, Janice H.; Crist, Joshua; Chansakul, Thanissara; Yang, Elaine C.; Jennifer H. Elisseeff

    2012-01-01

    Hyaluronic acid (HA) is an extracellular matrix molecule with multiple physical and biological functions found in many tissues, including cartilage. HA has been incorporated in a number of biomaterial and scaffold systems. Howegver, HA in the material may be difficult to control if it is not chemically modified and chemical modification of HA may negatively impact biological function. In this study, we developed a poly(ethylene glycol) hydrogel with noncovalent HA-binding capabilities and eva...

  7. Pathological change of articular cartilage in the mandibular head treated with immunosuppressant FK 506

    OpenAIRE

    Ueno, T; Kagawa, T; Kanou, M.; Fujii, T.; Fukunaga, J.; Mizukawa, N.; Sugahara, T.; Yamamoto, T.

    2004-01-01

    While several reports have documented immunosuppressant-induced osteoporosis, the exact mechanism of the pathological change of the joint remains to be clarified. In the present study, we have demonstrated the pathological change of the articular cartilage in the mandibular head of five Sprague-Dawley rats administered with the immunosuppressant FK 506 for 28 days. Three-dimensional micro-computed tomography of the mandibular heads in treated rats showed a ...

  8. Differential gene expression of the intermediate and outer interzone layers of developing articular cartilage in murine embryos.

    Science.gov (United States)

    Jenner, Florien; IJpma, Arne; Cleary, Mairead; Heijsman, Daphne; Narcisi, Roberto; van der Spek, Peter J; Kremer, Andreas; van Weeren, René; Brama, Pieter; van Osch, Gerjo J V M

    2014-08-15

    Nascent embryonic joints, interzones, contain a distinct cohort of progenitor cells responsible for the formation of the majority of articular tissues. However, to date the interzone has largely been studied using in situ analysis for candidate genes in the context of the embryo rather than using an unbiased genome-wide expression analysis on isolated interzone cells, leaving significant controversy regarding the exact role of the intermediate and outer interzone layers in joint formation. Therefore, in this study, using laser capture microdissection (three biological replicates), we selectively harvested the intermediate and outer interzones of mouse embryos at gestational age 15.5 days, just prior to cavitation, when the differences between the layers should be most profound. Microarray analysis (Agilent Whole Mouse Genome Oligo Microarrays) was performed and the differential gene expression between the intermediate interzone cells and outer interzone cells was examined by performing a two-sided paired Student's t-test and pathway analysis. One hundred ninety-seven genes were differentially expressed (≥ 2-fold) between the intermediate interzone and the outer interzone with a P-value ≤ 0.01. Of these, 91 genes showed higher expression levels in the intermediate interzone and 106 were expressed higher in the outer interzone. Pathway analysis of differentially expressed genes suggests an important role for inflammatory processes in the interzone layers, especially in the intermediate interzone, and hence in joint and articular cartilage development. The high representation of genes relevant to chondrocyte hypertrophy and endochondral ossification in the outer interzone suggests that it undergoes endochondral ossification. PMID:24738827

  9. Poroelastic response of articular cartilage by nanoindentation creep tests at different characteristic lengths.

    Science.gov (United States)

    Taffetani, M; Gottardi, R; Gastaldi, D; Raiteri, R; Vena, P

    2014-07-01

    Nanoindentation is an experimental technique which is attracting increasing interests for the mechanical characterization of articular cartilage. In particular, time dependent mechanical responses due to fluid flow through the porous matrix can be quantitatively investigated by nanoindentation experiments at different penetration depths and/or by using different probe sizes. The aim of this paper is to provide a framework for the quantitative interpretation of the poroelastic response of articular cartilage subjected to creep nanoindentation tests. To this purpose, multiload creep tests using spherical indenters have been carried out on saturated samples of mature bovine articular cartilage achieving two main quantitative results. First, the dependence of indentation modulus in the drained state (at equilibrium) on the tip radius: a value of 500 kPa has been found using the large tip (400 μm radius) and of 1.7 MPa using the smaller one (25 μm). Secon, the permeability at microscopic scale was estimated at values ranging from 4.5×10(-16) m(4)/N s to 0.1×10(-16) m(4)/N s, from low to high equivalent deformation. Consistently with a poroelastic behavior, the size-dependent response of the indenter displacement disappears when characteristic size and permeability are accounted for. For comparison purposes, the same protocol was applied to intrinsically viscoelastic homogeneous samples of polydimethylsiloxane (PDMS): both indentation modulus and time response have been found size-independent. PMID:24814573

  10. Electrostatic and Non-Electrostatic Contributions of Proteoglycans to the Compressive Equilibrium Modulus of Bovine Articular Cartilage

    OpenAIRE

    Guterl, Clare Canal; Hung, Clark T.; Ateshian, Gerard A.

    2010-01-01

    This study presents direct experimental evidence for assessing the electrostatic and nonelectrostatic contributions of proteoglycans to the compressive equilibrium modulus of bovine articular cartilage. Immature and mature bovine cartilage samples were tested in unconfined compression and their depth-dependent equilibrium compressive modulus was determined using strain measurements with digital image correlation analysis. The electrostatic contribution was assessed by testing samples in isoto...

  11. Articular cartilage echography as a criterion of the evolution of osteoarthritis of the knee.

    Science.gov (United States)

    Martino, F; Ettorre, G C; Patella, V; Macarini, L; Moretti, B; Pesce, V; Resta, L

    1993-01-01

    We propose a modification of the Aisen's technique by which precise reproducible measurements of articular cartilage thickness of the knee is possible. A group of 23 patients with severe osteoarthritis was studied by ultra-sound (US) before knee prosthesis surgery. Evaluation with US was performed by a real-time scanner with a 7.5 MHz linear probe with upper-patellar transverse scans tangent to the upper patellar pole at 90 degrees knee flexion. The cartilage thickness was measured within the weight-bearing area. After surgery, on the corresponding gross pathological specimen, US re-evaluation and histological measurements were made. Results of pre- and post-operative ultrasonography (US) data were compared with histological data and a good correlation between these measurements was found (p(t) > 10%). Preoperative measurements ranged from 2.4 to 0.3 mm. In order to obtain normal reference values of the articular cartilage within the weight-bearing area of the femoral trochlea for comparison, a group of 10 control subjects was also studied with US as above. The US data were then compared with computed tomography (arthro-CT) evaluations. No significant differences in mean values were found between the two imaging techniques (2.2 mm versus 2.3 mm for the lateral condyle and 2.3 versus 2.3 for the medial condyle, respectively). We conclude that ultra-sound measurement of articular cartilage thickness of femoral condyles is a sensitive and reproducible technique which permits early diagnosis and management of knee arthropathy and also quantification of cartilage damage. PMID:7995680

  12. The mechanism of inhibition of endothelin-1-induced stimulation of DNA synthesis in rat articular chondrocytes.

    Science.gov (United States)

    Khatib, A M; Ribault, D; Quintero, M; Barbara, A; Fiet, J; Mitrovic, D R

    1997-09-19

    Endothelin-1 (ET-1) is a potent mitogen for rat articular chondrocytes (AC) in short term culture (24 h). Prolonged incubation (72 h) of AC with ET-1 resulted in inhibition of [3H]thymidine incorporation. This inhibition seemed to be mediated by prostaglandins (PGs) released in response to ET-1, since indomethacin (INDO) enhanced ET-1-induced [3H]thymidine incorporation. In agreement with this hypothesis, exogenous prostaglandins (PGE2, PGF2alpha and TxB2) blocked all basal, ET-1-induced and ET-1 induced-INDO-enhanced [3H]thymidine incorporation and ET-1 stimulated PGE2 release in a time and concentration-dependent manner. INDO also blocked cGMP production and 6-anilino-5,8-quinolinedione, a relatively specific inhibitor of cGMP formation, enhanced the stimulation and suppressed the inhibition of ET-1-induced DNA synthesis. In addition, 8-bromo-cGMP, an analogue of cGMP, blocked at all time periods studied, both basal and ET-1-induced incorporations of [3H]thymidine. Thus, PGs produced in response to ET-1 counteract the ET-1-induced stimulation of [3H]thymidine incorporation into rat AC by increasing cGMP production. PMID:9324043

  13. The Immunosuppressant FTY720 (Fingolimod enhances Glycosaminoglycan depletion in articular cartilage

    Directory of Open Access Journals (Sweden)

    Stradner Martin H

    2011-12-01

    Full Text Available Abstract Background FTY720 (Fingolimod is a novel immunosuppressive drug investigated in clinical trials for organ transplantation and multiple sclerosis. It acts as a functional sphingosine-1-phosphate (S1P receptor antagonist, thereby inhibiting the egress of lymphocytes from secondary lymphoid organs. As S1P is able to prevent IL-1beta induced cartilage degradation, we examined the direct impact of FTY720 on cytokine induced cartilage destruction. Methods Bovine chondrocytes were treated with the bioactive phosphorylated form of FTY720 (FTY720-P in combination with IL-1beta or TNF-alpha. Expression of MMP-1,-3.-13, iNOS and ADAMTS-4,-5 and COX-2 was evaluated using quantitative real-time PCR and western blot. Glycosaminoglycan depletion from cartilage explants was determined using a 1,9-dimethylene blue assay and safranin O staining. Results FTY720-P significantly reduced IL-1beta and TNF-alpha induced expression of iNOS. In contrast FTY720-P increased MMP-3 and ADAMTS-5 mRNA expression. Furthermore depletion of glycosaminoglycan from cartilage explants by IL-1beta and TNF-alpha was significantly enhanced by FTY720-P in an MMP-3 dependent manner. Conclusions Our results suggest that FTY720 may enhance cartilage degradation in pro-inflammatory environment.

  14. Discrimination of healthy and osteoarthritic articular cartilage by Fourier transform infrared imaging and Fisher's discriminant analysis.

    Science.gov (United States)

    Mao, Zhi-Hua; Yin, Jian-Hua; Zhang, Xue-Xi; Wang, Xiao; Xia, Yang

    2016-02-01

    Fourier transform infrared spectroscopic imaging (FTIRI) technique can be used to obtain the quantitative information of content and spatial distribution of principal components in cartilage by combining with chemometrics methods. In this study, FTIRI combining with principal component analysis (PCA) and Fisher's discriminant analysis (FDA) was applied to identify the healthy and osteoarthritic (OA) articular cartilage samples. Ten 10-μm thick sections of canine cartilages were imaged at 6.25μm/pixel in FTIRI. The infrared spectra extracted from the FTIR images were imported into SPSS software for PCA and FDA. Based on the PCA result of 2 principal components, the healthy and OA cartilage samples were effectively discriminated by the FDA with high accuracy of 94% for the initial samples (training set) and cross validation, as well as 86.67% for the prediction group. The study showed that cartilage degeneration became gradually weak with the increase of the depth. FTIRI combined with chemometrics may become an effective method for distinguishing healthy and OA cartilages in future. PMID:26977354

  15. Biochemical and metabolic abnormalities in normal and osteoarthritic human articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, J.; Treadwell, B.V.; Mankin, H.J.

    1984-01-01

    Incorporation of radioactive precursors into macromolecules was studied with human normal and osteoarthritic articular cartilage organ culture. Analysis of the salt extracted matrix components separated by cesium chloride buoyant density gradient centrifugation showed an increase in the specific activities of all gradient fractions prepared from the osteoarthritic cartilage. Further analysis of these fractions showed the osteoarthritic cartilage contained 5 times as much sulfate incorporated into proteoglycans, and an even greater amount of 3H-glucosamine incorporated into material sedimenting to the middle of the gradient. Greater than half of this radioactive middle fraction appears to be hyaluronate, as judged by the position it elutes from a DEAE column and its susceptibility to hyaluronidase digestion. This study supports earlier findings showing increased rates of macromolecular synthesis in osteoarthritis, and in addition, an even greater synthetic rate for hyaluronic acid is demonstrated.

  16. Composite three-dimensional woven scaffolds with interpenetrating network hydrogels to create functional synthetic articular cartilage.

    Science.gov (United States)

    Liao, I-Chien; Moutos, Franklin T; Estes, Bradley T; Zhao, Xuanhe; Guilak, Farshid

    2013-12-17

    The development of synthetic biomaterials that possess mechanical properties that mimic those of native tissues remains an important challenge to the field of materials. In particular, articular cartilage is a complex nonlinear, viscoelastic, and anisotropic material that exhibits a very low coefficient of friction, allowing it to withstand millions of cycles of joint loading over decades of wear. Here we show that a three-dimensionally woven fiber scaffold that is infiltrated with an interpenetrating network hydrogel can provide a functional biomaterial that provides the load-bearing and tribological properties of native cartilage. An interpenetrating dual-network "tough-gel" consisting of alginate and polyacrylamide was infused into a porous three-dimensionally woven poly(ε-caprolactone) fiber scaffold, providing a versatile fiber-reinforced composite structure as a potential acellular or cell-based replacement for cartilage repair. PMID:24578679

  17. The Application of Polysaccharide Biocomposites to Repair Cartilage Defects

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-01-01

    Full Text Available Owing to own nature of articular cartilage, it almost has no self-healing ability once damaged. Despite lots of restore technologies having been raised in the past decades, no repair technology has smoothly substituted for damaged cartilage using regenerated cartilage tissue. The approach of tissue engineering opens a door to successfully repairing articular cartilage defects. For instance, grafting of isolated chondrocytes has huge clinical potential for restoration of cartilage tissue and cure of chondral injury. In this paper, SD rats are used as subjects in the experiments, and they are classified into three groups: natural repair (group A, hyaluronic acid repair (group B, and polysaccharide biocomposites repair (hyaluronic acid hydrogel containing chondrocytes, group C. Through the observation of effects of repairing articular cartilage defects, we concluded that cartilage repair effect of polysaccharide biocomposites was the best at every time point, and then the second best was hyaluronic acid repair; both of them were better than natural repair. Polysaccharide biocomposites have good biodegradability and high histocompatibility and promote chondrocytes survival, reproduction, and spliting. Moreover, polysaccharide biocomposites could not only provide the porous network structure but also carry chondrocytes. Consequently hyaluronic acid-based polysaccharide biocomposites are considered to be an ideal biological material for repairing articular cartilage.

  18. The influence of collagen network integrity on the accumulation of gadolinium-based MR contrast agents in articular cartilage

    International Nuclear Information System (INIS)

    Delayed gadolinium-enhanced MR imaging of cartilage is used to quantify the proteoglycan loss in early osteoarthritis. It is assumed that T 1 after Gd-DTPA administration in the near equilibrium state reflects selective proteoglycan loss from cartilage. To investigate the influence of the collagen network integrity on contrast accumulation, the relaxation rates ΔR1 and ΔR2 were compared after Gd-DTPA administration in a well established model of osteoarthritis. Collagen or proteoglycan depletion was induced by the proteolytic enzymes papain and collagenase in healthy bovine patellar cartilage. Using a dedicated MRI sequence, T1 and T2 maps were simultaneously acquired before and 11 h after Gd-DTPA administration. Depth-dependent profiles of ΔR1 and ΔR2 were calculated in healthy, proteoglycan and collagen-depleted articular cartilage and the mean values of different cartilage layers were compared using the Mann-Whitney-U test. In superficial layers (1 mm) there was no significant difference (p > 0.05) in either ΔR1 or ΔR2 between proteoglycan-depleted (16.6 ± 1.2 s-1, 15.9 ± 1.0 s-1) and collagen-depleted articular cartilage (15.3 ± 0.9 s-1, 15.5 ± 0.9 s-1). In deep layers (3 mm) both parameters were significantly higher (p = 0.005, 0.03) in proteoglycan-depleted articular cartilage (12.3 ± 1.1 s-1, 9.8 ± 0.8 s-1) than in collagen-depleted articular cartilage (9.1 ± 1.1 s-1, 8.7 ± 0.7 s-1). Both proteoglycan loss and alterations in the collagen network influence the accumulation of Gd-DTPA in articular cartilage with significant differences between superficial and deep cartilage layers. (orig.)

  19. Autologous chondrocyte implantation (ACI for the treatment of large and complex cartilage lesions of the knee

    Directory of Open Access Journals (Sweden)

    Ossendorf Christian

    2011-05-01

    Full Text Available Abstract Background Complex cartilage lesions of the knee including large cartilage defects, kissing lesions, and osteoarthritis (OA represent a common problem in orthopaedic surgery and a challenging task for the orthopaedic surgeon. As there is only limited data, we performed a prospective clinical study to investigate the benefit of autologous chondrocyte implantation (ACI for this demanding patient population. Methods Fifty-one patients displaying at least one of the criteria were included in the present retrospective study: (1. defect size larger than 10 cm2; (2. multiple lesions; (3. kissing lesions, cartilage lesions Outerbridge grade III-IV, and/or (4. mild/moderate osteoarthritis (OA. For outcome measurements, the International Cartilage Society's International Knee Documentation Committee's (IKDC questionnaire, as well as the Cincinnati, Tegner, Lysholm and Noyes scores were used. Radiographic evaluation for OA was done using the Kellgren score. Results and Discussion Patient's age was 36 years (13-61, defects size 7.25 (3-17.5 cm2, previous surgical procedures 1.94 (0-8, and follow-up 30 (12-63 months. Instruments for outcome measurement indicated significant improvement in activity, working ability, and sports. Mean ICRS grade improved from 3.8 preoperatively to grade 3 postoperatively, Tegner grade 1.4 enhanced to grade 3.39. The Cincinnati score enhanced from 25.65 to 66.33, the Lysholm score from 33.26 to 64.68, the Larson score from 43.59 to 79.31, and Noyes score from 12.5 to 46.67, representing an improvement from Cincinnati grade 3.65 to grade 2.1. Lysholm grade 4 improved to grade 3.33, and Larson grade 3.96 to 2.78 (Table 1, (p Table 1 Mean scores and grades at surgery (Tx and at follow-up Tx Follow-up Score Grade Score Grade ICRS 4 3 Tegner 1 3 Noyes 13 47 Cincinnati 26 4 66 2 Lysholm 33 4 65 3 Larson 44 4 79 3 Conclusion Our results suggest that ACI provides mid-term results in patients with complex cartilage lesions of

  20. Effects of tenoxicam and aspirin on the metabolism of proteoglycans and hyaluronan in normal and osteoarthritic human articular cartilage.

    OpenAIRE

    Manicourt, Daniel; Druetz-Van Egeren, A; Haazen, L.; Nagant de Deuxchaisnes, C

    1994-01-01

    1. As nonsteroidal anti-inflammatory drugs may impair the ability of the chondrocyte to repair its damaged extracellular matrix, we explored the changes in the metabolism of newly synthesized proteoglycan (PG) and hyaluronan (HA) molecules produced by tenoxicam and aspirin in human normal cartilage explants and in osteoarthritic (OA) cartilage from age-matched donors. 2. Explants were sampled from the medial femoral condyle and were classified by use of Mankin's histological-histochemical gra...

  1. The pro-inflammatory cytokine 14-3-3ε is a ligand of CD13 in cartilage

    OpenAIRE

    Nefla, Meriam; Sudre, Laure; Denat, Guillaume; Priam, Sabrina; André-Leroux, Gwenaelle; Jacques, Claire

    2015-01-01

    ABSTRACT Osteoarthritis is a whole-joint disease characterized by the progressive destruction of articular cartilage involving abnormal communication between subchondral bone and cartilage. Our team previously identified 14-3-3ε protein as a subchondral bone soluble mediator altering cartilage homeostasis. The aim of this study was to investigate the involvement of CD13 (also known as aminopeptidase N, APN) in the chondrocyte response to 14-3-3ε. After identifying CD13 in chondrocytes, we kno...

  2. Of mice, men and elephants: the relation between articular cartilage thickness and body mass.

    Directory of Open Access Journals (Sweden)

    Jos Malda

    Full Text Available Mammalian articular cartilage serves diverse functions, including shock absorption, force transmission and enabling low-friction joint motion. These challenging requirements are met by the tissue's thickness combined with its highly specific extracellular matrix, consisting of a glycosaminoglycan-interspersed collagen fiber network that provides a unique combination of resilience and high compressive and shear resistance. It is unknown how this critical tissue deals with the challenges posed by increases in body mass. For this study, osteochondral cores were harvested post-mortem from the central sites of both medial and lateral femoral condyles of 58 different mammalian species ranging from 25 g (mouse to 4000 kg (African elephant. Joint size and cartilage thickness were measured and biochemical composition (glycosaminoclycan, collagen and DNA content and collagen cross-links densities were analyzed. Here, we show that cartilage thickness at the femoral condyle in the mammalian species investigated varies between 90 µm and 3000 µm and bears a negative allometric relationship to body mass, unlike the isometric scaling of the skeleton. Cellular density (as determined by DNA content decreases with increasing body mass, but gross biochemical composition is remarkably constant. This however need not affect life-long performance of the tissue in heavier mammals, due to relatively constant static compressive stresses, the zonal organization of the tissue and additional compensation by joint congruence, posture and activity pattern of larger mammals. These findings provide insight in the scaling of articular cartilage thickness with body weight, as well as in cartilage biochemical composition and cellularity across mammalian species. They underscore the need for the use of appropriate in vivo models in translational research aiming at human applications.

  3. Interleukin-1 induced nitric oxide inhibits sulphation of glycosaminoglycan chains in human articular chondrocytes.

    Science.gov (United States)

    Hickery, M S; Bayliss, M T

    1998-10-23

    Incubation of human articular cartilage explants with interleukin-1alpha (IL-1alpha) inhibited the rate of [35S]sulphate incorporation into glycosaminoglycan (GAG) chains concomitant with an increase in nitric oxide (NO) production. Measurement of the [35S]sulphate showed that IL-1alpha inhibited the synthesis of both keratan sulphate and chondroitin sulphate (CS) chains to a similar extent. This effect was reversed by the NO synthase inhibitor Nomega-iminoethyl-l-ornithine (l-NIO). Analysis of alkali borohydride cleaved GAG chains showed that IL-1alpha had no effect on their size. Similarly when GAG chains were coupled to xyloside the size of the GAG chains attached to the exogenous acceptor decreased but IL-1alpha had no further effect on hydrodynamic size. IL-1alpha did, however, inhibit [35S]sulphate incorporation into xyloside-linked CS chains. In both experiments l-NIO reversed the inhibitory effect on sulphation. Disaccharide analysis of the [35S]GAG chains showed that IL-1alpha preferentially inhibited sulphation of the 6-sulphated isomer and that l-NIO reversed this effect. Thus, IL-1alpha-induced NO mediates the inhibition of sulphate incorporation and alters the sulphation pattern of newly synthesised GAG chains. PMID:9795242

  4. Gender differences in knee joint cartilage thickness, volume and articular surface areas: assessment with quantitative three-dimensional MR imaging

    International Nuclear Information System (INIS)

    Objective: To compare the cartilage thickness, volume, and articular surface areas of the knee joint between young healthy, non-athletic female and male individuals. Subjects and design. MR imaging was performed in 18 healthy subjects without local or systemic joints disease (9 female, age 22.3±2.4 years, and 9 male, age 22.2.±1.9 years), using a fat-suppressed FLASH 3D pulse sequence (TR=41 ms, TE=11 ms, FA=30 ) with sagittal orientation and a spatial resolution of 2x0.31x0.31 mm3. After three-dimensional reconstruction and triangulation of the knee joint cartilage plates, the cartilage thickness (mean and maximal), volume, and size of the articular surface area were quantified, independent of the original section orientation. Results and conclusions: Women displayed smaller cartilage volumes than men, the percentage difference ranging from 19.9% in the patella, to 46.6% in the medial tibia. The gender differences of the cartilage thickness were smaller, ranging from 2.0% in the femoral trochlea to 13.3% in the medial tibia for the mean thickness, and from 4.3% in the medial femoral condyle to 18.3% in the medial tibia for the maximal cartilage thickness. The differences between the cartilage surface areas were similar to those of the volumes, with values ranging from 21.0% in the femur to 33.4% in the lateral tibia. Gender differences could be reduced for cartilage volume and surface area when normalized to body weight and body weight x body height. The study demonstrates significant gender differences in cartilage volume and surface area of men and women, which need to be taken into account when retrospectively estimating articular cartilage loss in patients with symptoms of degenerative joint disease. Differences in cartilage volume are primarily due to differences in joint surface areas (epiphyseal bone size), not to differences in cartilage thickness. (orig.)

  5. Studies on the hyaluronate binding properties of newly synthesized proteoglycans purified from articular chondrocyte cultures

    Energy Technology Data Exchange (ETDEWEB)

    Sandy, J.D.; Plaas, A.H.

    1989-06-01

    Primary cultures of rabbit articular chondrocytes have been maintained for 10 days and labeled with (35S)sulfate, (3H)leucine, and (35S)cysteine in pulse-chase protocols to study the structure and hyaluronate binding properties of newly synthesized proteoglycan monomers. Radiolabeled monomers were purified from medium and cell-layer fractions by dissociative CsCl gradient centrifugation with bovine carrier monomer, and analyzed for hyaluronate binding affinity on Sepharose CL-2B in 0.5 M Na acetate, 0.1% Triton X-100, pH 6.8. Detergent was necessary to prevent self-association of newly synthesized monomers during chromatography. Monomers secreted during a 30-min pulse labeling with (35S)sulfate had a low affinity relative to carrier. Those molecules released into the medium during the first 12 h of chase remained in the low affinity form whereas those retained by the cell layer rapidly acquired high affinity. In cultures where more than 90% of the preformed cell-layer proteoglycan was removed by hyaluronidase digestion before radiolabeling the newly synthesized low affinity monomers also rapidly acquired high affinity if retained in the cell layer. Cultures labeled with amino acid precursors were used to establish the purity of monomer preparations and to isolate core proteins for study. Leucine- or cysteine-labeled core proteins derived from either low or high affinity monomer preparations migrated as a single major species on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with electrophoretic mobility very similar to that of core protein derived from extracted proteoglycan monomer. Purified low affinity monomers were converted to the high affinity form by treatment at pH 8.6; however, this change was prevented by guanidinium-HCl at concentrations above 0.8 M.

  6. Homology of lubricin and superficial zone protein (SZP): products of megakaryocyte stimulating factor (MSF) gene expression by human synovial fibroblasts and articular chondrocytes localized to chromosome 1q25.

    Science.gov (United States)

    Jay, G D; Tantravahi, U; Britt, D E; Barrach, H J; Cha, C J

    2001-07-01

    We have previously identified megakaryocyte stimulating factor (MSF) gene expression by synovial fibroblasts as the origin of lubricin in the synovial cavity. Lubricin is a mucinous glycoprotein responsible for the boundary lubrication of articular cartilage. MSF has a significant homology to vitronectin and is composed of 12 exons. RNA was purified from human synovial fibroblasts and articular chondrocytes grown in vitro from tissue explants obtained from subjects without degenerative joint disease. RT-PCR was used with multiple complimentary primer pairs spanning the central mucin expressing exon 6 of the MSF gene and individual exons on both the N- and C-terminal sides of exon 6. Exons 2, 4 and 5 appear to be variably expressed by synovial fibroblasts and articular chondrocytes. Lubricating mucin, in the form of MSF, is expressed by both chondrocytes and synovial fibroblasts in vitro. Both lubricin and superficial zone protein (SZP), a related proteoglycan, share a similar primary structure but could differ in post-translational modifications with O-linked oligosaccharides which are predominant in lubricin and with limited amounts chondroitin and keratan sulfate found in SZP. Since most of the MSF exons are involved in the expression of lubricating mucin, a strong homology to vitronectin persists. It is therefore appropriate to consider that both SZP and lubricin occupy a new class of biomolecules termed tribonectins. Screening of a human genome bacterial artificial chromsome (BAC) library with a cDNA primer pair complimentary for exon 6 identified two clones. Both clones were complimentary for chromosome 1q25 by in situ hybridization. This same locus was previously implicated in camptodactyl-arthropathy-pericarditis syndrome (CAP) by genetic mapping. It is hypothesized that CAP, a large joint arthropathy, may be associated with ineffective boundary lubrication provided by synovial fluid. PMID:11518279

  7. Effects of refrigeration and freezing on the electromechanical and biomechanical properties of articular cartilage.

    Science.gov (United States)

    Changoor, Adele; Fereydoonzad, Liah; Yaroshinsky, Alex; Buschmann, Michael D

    2010-06-01

    In vitro electromechanical and biomechanical testing of articular cartilage provide critical information about the structure and function of this tissue. Difficulties obtaining fresh tissue and lengthy experimental testing procedures often necessitate a storage protocol, which may adversely affect the functional properties of cartilage. The effects of storage at either 4°C for periods of 6 days and 12 days, or during a single freeze-thaw cycle at -20°C were examined in young bovine cartilage. Non-destructive electromechanical measurements and unconfined compression testing on 3 mm diameter disks were used to assess cartilage properties, including the streaming potential integral (SPI), fibril modulus (Ef), matrix modulus (Em), and permeability (k). Cartilage disks were also examined histologically. Compared with controls, significant decreases in SPI (to 32.3±5.5% of control values, prefrigeration at 4°C, but no significant changes were detected at day 6. A trend toward detecting a decrease in SPI (to 94.2±6.2% of control values, p=0.083) was identified following a single freeze-thaw cycle, but no detectable changes were observed for any biomechanical parameters. All numbers are mean±95% confidence interval. These results indicate that fresh cartilage can be stored in a humid chamber at 4°C for a maximum of 6 days with no detrimental effects to cartilage electromechanical and biomechanical properties, while one freeze-thaw cycle produces minimal deterioration of biomechanical and electromechanical properties. A comparison to literature suggested that particular attention should be paid to the manner in which specimens are thawed after freezing, specifically by minimizing thawing time at higher temperatures. PMID:20887036

  8. The effects of proteoglycan and type II collagen on T1rho relaxation time of articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Won Seok; Yoo, Hye Jin; Hong, Sung Hwan; Choi, Ja Young [Dept. of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2015-02-15

    To evaluate the effects of proteoglycan and type II collagen within articular cartilage on T1rho relaxation time of articular cartilage. This study was exempted by the institutional and animal review boards, and informed consent was not required. Twelve porcine patellae were assigned to three groups of control, trypsin-treated (proteoglycan-degraded), or collagenase-treated (collagen-degraded). The T1rho images were obtained with a 3 tesla magnetic resonance imaging scanner with a single loop coil. Statistical differences were detected by analysis of variance to evaluate the effects of the enzyme on T1rho relaxation time. Safranin-O was used to stain proteoglycan in the articular cartilage and immunohistochemical staining was performed for type II collagen. Mean T1rho values of the control, trypsin-treated, and collagenase-treated groups were 37.72 +/- 5.82, 57.53 +/- 8.24, and 45.08 +/- 5.31 msec, respectively (p < 0.001). Histology confirmed a loss of proteoglycan and type II collagen in the trypsin- and collagenase-treated groups. Degradation of proteoglycans and collagen fibers in the articular cartilage increased the articular cartilage T1rho value.

  9. Treatment with recombinant lubricin attenuates osteoarthritis by positive feedback loop between articular cartilage and subchondral bone in ovariectomized rats.

    Science.gov (United States)

    Cui, Zhuang; Xu, Changpeng; Li, Xue; Song, Jinqi; Yu, Bin

    2015-05-01

    Osteoarthritis (OA) is a most commonly multifactorial degenerative joint disease along with the aging population, particularly in postmenopausal women. During the onset of OA, articular cartilage and subchondral bone act in concert as a functional unit. This present study is to investigate the effects of early or late treatment with recombinant lubricin on the onset of osteoarthritis (OA) in ovariectomized (OVX) rats. We found that both early and late recombinant lubricin treatments attenuated the onset of OA by positive feedback loop between articular cartilage and subchondral bone, although late treatment contributed to a lesser effect compared with early treatment. Specifically, treatment with recombinant lubricin protected articular cartilage from degeneration, demonstrated by lower proteoglycan loss, lower OARSI scores, less calcification cartilage zone and reduced immunostaining for collagen X (Col X) and matrix metalloproteinase (MMP-13) but increased the expression of lubricin, in comparison with vehicle-treated OVX rat group. Further, chondroprotective effects of lubricin normalized bone remodeling in subchondral bone underneath. It's suggested that treatment with recombinant lubricin inhibited the elevation of TRAP and Osterix positive cells in OVX rats and led to the normalization of subchondral bone microarchitectures with the suppression of subsidence of bone volume ratio (BV/TV) and trabecular thickness (Tb.Th) and the increase of trabecular separation (Tb.Sp) in vehicle-treated OVX rats. What's more, the normalization of subchondral bone in turn attenuated the articular cartilage erosion by inhibiting vascular invasion from subchondral bone to calcified cartilage zone, exemplified by inhibiting the elevation of CD31 positive cells in calcified cartilage and angiography in subchondral bone. Together, these results shed light that both early and late recombinant lubricin treatments attenuate the onset of OA by balancing the interplay between articular

  10. IFT88 influences chondrocyte actin organization and biomechanics

    OpenAIRE

    Z. Wang; Wann, A.K.T.; Thompson, C L; Hassen, A.; Wang, W; Knight, M.M.

    2016-01-01

    Summary Objectives Primary cilia are microtubule based organelles which control a variety of signalling pathways important in cartilage development, health and disease. This study examines the role of the intraflagellar transport (IFT) protein, IFT88, in regulating fundamental actin organisation and mechanics in articular chondrocytes. Methods The study used an established chondrocyte cell line with and without hypomorphic mutation of IFT88 (IFT88orpk). Confocal microscopy was used to quantif...

  11. Study on nano-structured hydroxyapatite/zirconia stabilized yttria on healing of articular cartilage defect in rabbit

    Directory of Open Access Journals (Sweden)

    Amir Sotoudeh

    2013-05-01

    Full Text Available PURPOSE: Articular Cartilage has limited potential for self-repair and tissue engineering approaches attempt to repair articular cartilage by scaffolds. We hypothesized that the combined hydroxyapatite and zirconia stabilized yttria would enhance the quality of cartilage healing. METHODS: In ten New Zealand white rabbits bilateral full-thickness osteochondral defect, 4 mm in diameter and 3 mm depth, was created on the articular cartilage of the patellar groove of the distal femur. In group I the scaffold was implanted into the right stifle and the same defect was created in the left stifle without any transplant (group II. Specimens were harvested at 12 weeks after implantation, examined histologically for morphologic features, and stained immunohistochemically for type-II collagen. RESULTS: In group I the defect was filled with a white translucent cartilage tissue In contrast, the defects in the group II remained almost empty. In the group I, the defects were mostly filled with hyaline-like cartilage evidenced but defects in group II were filled with fibrous tissue with surface irregularities. Positive immunohistochemical staining of type-II collagen was observed in group I and it was absent in the control group. CONCLUSION: The hydroxyapatite/yttria stabilized zirconia scaffold would be an effective scaffold for cartilage tissue engineering.

  12. In vivo articular cartilage deformation: noninvasive quantification of intratissue strain during joint contact in the human knee

    Science.gov (United States)

    Chan, Deva D.; Cai, Luyao; Butz, Kent D.; Trippel, Stephen B.; Nauman, Eric A.; Neu, Corey P.

    2016-01-01

    The in vivo measurement of articular cartilage deformation is essential to understand how mechanical forces distribute throughout the healthy tissue and change over time in the pathologic joint. Displacements or strain may serve as a functional imaging biomarker for healthy, diseased, and repaired tissues, but unfortunately intratissue cartilage deformation in vivo is largely unknown. Here, we directly quantified for the first time deformation patterns through the thickness of tibiofemoral articular cartilage in healthy human volunteers. Magnetic resonance imaging acquisitions were synchronized with physiologically relevant compressive loading and used to visualize and measure regional displacement and strain of tibiofemoral articular cartilage in a sagittal plane. We found that compression (of 1/2 body weight) applied at the foot produced a sliding, rigid-body displacement at the tibiofemoral cartilage interface, that loading generated subject- and gender-specific and regionally complex patterns of intratissue strains, and that dominant cartilage strains (approaching 12%) were in shear. Maximum principle and shear strain measures in the tibia were correlated with body mass index. Our MRI-based approach may accelerate the development of regenerative therapies for diseased or damaged cartilage, which is currently limited by the lack of reliable in vivo methods for noninvasive assessment of functional changes following treatment.

  13. Elastoviscous Transitions of Articular Cartilage Reveal a Mechanism of Synergy between Lubricin and Hyaluronic Acid

    Science.gov (United States)

    Bonnevie, Edward D.; Galesso, Devis; Secchieri, Cynthia; Cohen, Itai; Bonassar, Lawrence J.

    2015-01-01

    When lubricated by synovial fluid, articular cartilage provides some of the lowest friction coefficients found in nature. While it is known that macromolecular constituents of synovial fluid provide it with its lubricating ability, it is not fully understood how two of the main molecules, lubricin and hyaluronic acid, lubricate and interact with one another. Here, we develop a novel framework for cartilage lubrication based on the elastoviscous transition to show that lubricin and hyaluronic acid lubricate by distinct mechanisms. Such analysis revealed nonspecific interactions between these molecules in which lubricin acts to concentrate hyaluronic acid near the tissue surface and promotes a transition to a low friction regime consistent with the theory of viscous boundary lubrication. Understanding the mechanics of synovial fluid not only provides insight into the progression of diseases such as arthritis, but also may be applicable to the development of new biomimetic lubricants. PMID:26599797

  14. Increased physical activity severely induces osteoarthritic changes in knee joints with papain induced sulfate-glycosaminoglycan depleted cartilage

    OpenAIRE

    Siebelt, M.; Groen, H.C.; Koelewijn, S. J.; de Blois, E.; Sandker, M.; Waarsing, J. H.; Müller, C.(Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, Sternwartstr. 7, 96049 , Bamberg, Germany); van Osch, G. J. V. M.; de Jong, M.; Weinans, H.H.

    2014-01-01

    Introduction Articular cartilage needs sulfated-glycosaminoglycans (sGAGs) to withstand high pressures while mechanically loaded. Chondrocyte sGAG synthesis is regulated by exposure to compressive forces. Moderate physical exercise is known to improve cartilage sGAG content and might protect against osteoarthritis (OA). This study investigated whether rat knee joints with sGAG depleted articular cartilage through papain injections might benefit from moderate exercise, or whether this increase...

  15. Effect of nitric oxide synthase inhibitor on proteoglycan metabolism in repaired articular cartilage in rabbits

    Institute of Scientific and Technical Information of China (English)

    孙炜; 金大地; 王吉兴; 秦立赟; 刘晓霞

    2003-01-01

    Objective: To study the effect of nitric oxide synthase inhibitor, S-methyl thiocarbamate (SMT), on proteoglycan metabolism in repaired articular cartilage in rabbits. Methods: Twenty-four male New Zealand white rabbits, aged 8 months and weighing 2.5 kg±0.2 kg, were used in this study. Cartilage defects in full thickness were created on the intercondylar articular surface of bilateral femurs of all the rabbits. Then the rabbits were randomly divided into 3 groups (n=8 in each group). The defects in one group were filled with fibrin glue impregnated with recombinant human bone morphogenetic protein-2 (rhBMP-2, BMP group), in one group with fibrin glue impregnated with rhBMP-2 and hypodermic injection with SMT (SMT group) and in the other group with nothing (control group). All the animals were killed at one year postoperatively. The tissue sections were stained with safranine O-fast green and analyzed by Quantiment 500 system to determine the content of glycosaminoglycan through measuring the percentage of safranine O-stained area, the thickness of cartilages and the mean gray scale (average stain intensity). Radiolabelled sodium sulphate (Na235SO4) was used to assess the proteoglycan synthesis. Results: At one year postoperatively, the percentage of safranine O-stained area, the mean gray scale and the cartilage thickness of the repaired tissues in SMT group were significantly higher than those of BMP group (P<0.01) and the control group (P<0.05). Result of incorporation of Na235SO4 showed that the proteoglycan synthesis in SMT group was higher than those of BMP group and the control group (P<0.01). Conclusions: SMT, a nitric oxide synthase inhibitor, can significantly increase the content of glycosaminoglycan and proteoglycan synthesis, and computer-based image analysis is a reliable method for evaluating proteoglycan metabolism.

  16. Designed composites for mimicking compressive mechanical properties of articular cartilage matrix.

    Science.gov (United States)

    Zhu, Youjia; Wu, Hua; Sun, Shaofa; Zhou, Ting; Wu, Jingjing; Wan, Ying

    2014-08-01

    Collagen, chitosan-polycaprolactone (CH-PCL) copolymer with PCL content of around 40wt% and chondroitin sulfate (CS) were mixed together at various ratios to prepare collagen/CH-PCL/CS composites and the resulting composites were used to build stratified porous scaffolds that are potentially applicable for articular cartilage repair. The ternary composites were designed in such a way that collagen content in the scaffolds decreased from the top layer to the bottom layer while the content of CH-PCL and CS altered in a reversed trend in order to reach partial similarity to cartilage matrix in the composition of main components. Porous structures inside collagen/CH-PCL/CS scaffolds were constructed using a low-temperature deposition processing technique and graded average pore-size and porosity for the scaffolds were established. Such produced scaffolds were further crosslinked using 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide under optimized conditions, and the obtained scaffolds showed well-defined elastic compressive properties. Compressive modulus (E) and stress at 10% strain (σ10) of full scaffolds in wet state reached about 2.8MPa and 0.3MPa, respectively, and meanwhile, E and σ10 of layers inside hydrated scaffolds changed in a gradient-increased manner from the top layer to the bottom layer with significant differences between contiguous layers, which partially mimics compressive mechanical properties of cartilage matrix. In addition, in vitro culture of cell-scaffold constructs exhibited that scaffolds were able to well support the ingrowth and migration of seeded cells, and cells also showed relatively uniform distribution throughout the scaffolds. These results suggest that the presently developed collagen/CH-PCL/CS scaffolds have promising potential for applications in articular cartilage repair. PMID:24793172

  17. Tissue engineering for articular cartilage repair – the state of the art

    Directory of Open Access Journals (Sweden)

    B Johnstone

    2013-05-01

    Full Text Available Articular cartilage exhibits little capacity for intrinsic repair, and thus even minor injuries or lesions may lead to progressive damage and osteoarthritic joint degeneration, resulting in significant pain and disability. While there have been numerous attempts to develop tissue-engineered grafts or patches to repair focal chondral and osteochondral defects, there remain significant challenges in the clinical application of cell-based therapies for cartilage repair. This paper reviews the current state of cartilage tissue engineering with respect to different cell sources and their potential genetic modification, biomaterial scaffolds and growth factors, as well as preclinical testing in various animal models. This is not intended as a systematic review, rather an opinion of where the field is moving in light of current literature. While significant advances have been made in recent years, the complexity of this problem suggests that a multidisciplinary approach – combining a clinical perspective with expertise in cell biology, biomechanics, biomaterials science and high-throughput analysis will likely be necessary to address the challenge of developing functional cartilage replacements. With this approach we are more likely to realise the clinical goal of treating both focal defects and even large-scale osteoarthritic degenerative changes in the joint.

  18. Linkage of chondroitin-sulfate to type I collagen scaffolds stimulates the bioactivity of seeded chondrocytes in vitro.

    NARCIS (Netherlands)

    Susante, J.L.C. van; Pieper, J.S.; Buma, P.; Kuppevelt, A.H.M.S.M. van; Beuningen, H.M. van; Kraan, P.M. van der; Veerkamp, J.H.; Berg, W.B. van den; Veth, R.P.H.

    2001-01-01

    An increasing amount of interest is focused on the potential use of tissue-engineered articular cartilage implants, for repair of defects in the joint surface. In this perspective, various biodegradable scaffolds have been evaluated as a vehicle to deliver chondrocytes into a cartilage defect. This

  19. [Growth behavior of chondrocytes on various biomaterials].

    Science.gov (United States)

    Rudert, M; Hirschmann, F; Wirth, C J

    1999-01-01

    Chondrocytes can be cultured on different three-dimensional culture systems suitable for transplantation to enhance the repair of localized cartilage defects. Articular cartilage chondrocytes from adult rabbit knees and from bovine calf metacarpophalangeal joints were isolated by enzymatic digestion and cultured in a monolayer system to amplify cell count. After amplification the cells were seeded on different biocompatible materials. We investigated two types of bioresorbable polymer fleece matrices (a composite fleece of polydioxanon and polyglactin and a resorbable poly-L-lactic acid fleece) and lyophilized dura as a biological carrier. On all three types of transport media the phenotypic and morphological appearance of cultured chondrocytes could be observed. The production of glycosaminoglycans was revealed by Alcian blue staining and immunohistochemical detection of Chondroitin-4 and 6-sulfate in the created constructs. The material properties of the carriers allow for transplantation of the artificial cartilage-like products into full thickness articular cartilage defects and could therefore improve the minor intrinsic healing capacity of cartilage tissue. Bioartificial cartilage may become a future perspective in the treatment options of orthopaedic and plastic surgery. PMID:10081046

  20. Delayed Gadolinium-Enhanced Magnetic Resonance Imaging (dGEMRIC) of Hip Joint Cartilage: Better Cartilage Delineation after Intra-Articular than Intravenous Gadolinium Injection

    DEFF Research Database (Denmark)

    Boesen, M.; Jensen, K.E.; Quistgaard, E.; Danneskiold-Samsøe, B.; Thomsen, C.; Østergaard, Mikkel; Bliddal, H.

    2006-01-01

    PURPOSE: To investigate and compare delayed gadolinium (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in the hip joint using intravenous (i.v.) or ultrasound-guided intra-articular (i.a.) Gd-DTPA injection. MATERIAL AND METHODS: In 10 patients (50% males, mean age 58...

  1. A biochemical model for characterising the surface-active phospolipid bilayer of articular cartilage relative to acid-base equilibrium

    OpenAIRE

    Z. Pawlak; J. Kotynska; Figaszewski, Z A; A. Gadomski; A. Gudaniec; A. Oloyede

    2008-01-01

    Purpose: This paper, addresses the question of how changes in acid - base equilibrium influence change in thecharge density of the phospholipid bilayer on articular cartilage surfaces during lubrication.Design/methodology/approach: Liposomes have been used to mimic biological phospholipid membranes onarticular cartilage surface where proteins are bounded, ions are transported, energy is transducted, and cellular processestake place. The charge density of the membrane was determined as a funct...

  2. Effects of 99Tc-MDP on synoviocytes and articular chondrocytes apoptosis associated factors on CIA rats

    International Nuclear Information System (INIS)

    Objective: Collagen induced arthritis (CIA) rats is an animal model of human rheumatoid arthritis (RA). It is widely used in research of the pathogenesis and the therapeutic targets of RA. This paper was to investigate the therapeutic action of 99Tc-methylene diphosphonic acid (MDP) on CIA rats and its effects on the expression of apoptosis associated factor bcl-2 and bax in synoviocytes and articular chondrocytes. Methods: CIA rat models were carried out by subcutaneous injection with bovine collagen II and incomplete Freud's adjuvant. Rats were divided into four groups: control group, CIA model group (the CIA rats were infused with physiological saline via tail vein daily), 99Tc-MDP group (the C1A rats were injected with 99Tc-Mi)P 0.04 μg 99Tc/kg via tail vein daily) and methotrexate (MTX) group (the CIA rats were injected with MTX 1 mg/kg via tail vein weekly). The signs of arthritis were evaluated by arthritis index (AI) scores. Immunohistochemistry was performed to detect the expression of bcl-2 and bax in synoviocytes and articular chondrocytes. SPSS 13.0 was used for data analysis. Results: (1) The signs of arthritis, AI scores and pathological changes of arthrosynovitis in CIA rats were significantly improved by 99Tc-MDP or MTX. (2) The expression of bcl-2 and box in the synoviocytes of CIA model group [(39.30 ± 0.53) %, (27.37 ± 2.45)%] was significantly increased compared with control group [(7.56 ± 1. 18)% , (6.14 ± 1.71) % ; q = 46.27, 24.57, all P 99Tc-M DP group and MTX group, the level of bcl-2 was remarkably decreased [(30.24 ± 2.09) %, (27.25 ± 3.33) %] compared with CIA model group (q = 13.20, 17.56, all P 99Tc-MDP group [(26. 58 ± 2. 52) %] and MTX group [(27.06 ± 1.92) %] was remarksbly increased [(24.26 ± 2.75) %, (23.53 ± 0.74) % ; q = 6.53, 7.01, all P 99Tc-MDP could improve the signs of arthritis, meanwhile regulate the expression of bcl-2 and bax in synoviocytes and articular ehondrocytes, suggesting that one of the therapeutic

  3. Effects of friction on the unconfined compressive response of articular cartilage: a finite element analysis.

    Science.gov (United States)

    Spilker, R L; Suh, J K; Mow, V C

    1990-05-01

    A finite element analysis is used to study a previously unresolved issue of the effects of platen-specimen friction on the response of the unconfined compression test; effects of platen permeability are also determined. The finite element formulation is based on the linear KLM biphasic model for articular cartilage and other hydrated soft tissues. A Galerkin weighted residual method is applied to both the solid phase and the fluid phase, and the continuity equation for the intrinsically incompressible binary mixture is introduced via a penalty method. The solid phase displacements and fluid phase velocities are interpolated for each element in terms of unknown nodal values, producing a system of first order differential equations which are solved using a standard numerical finite difference technique. An axisymmetric element of quadrilateral cross-section is developed and applied to the mechanical test problem of a cylindrical specimen of soft tissue in unconfined compression. These studies show that interfacial friction plays a major role in the unconfined compression response of articular cartilage specimens with small thickness to diameter ratios. PMID:2345443

  4. Characterization and Localization of Citrullinated Proteoglycan Aggrecan in Human Articular Cartilage.

    Directory of Open Access Journals (Sweden)

    Tibor T Glant

    Full Text Available Rheumatoid arthritis (RA is an autoimmune disease of the synovial joints. The autoimmune character of RA is underscored by prominent production of autoantibodies such as those against IgG (rheumatoid factor, and a broad array of joint tissue-specific and other endogenous citrullinated proteins. Anti-citrullinated protein antibodies (ACPA can be detected in the sera and synovial fluids of RA patients and ACPA seropositivity is one of the diagnostic criteria of RA. Studies have demonstrated that RA T cells respond to citrullinated peptides (epitopes of proteoglycan (PG aggrecan, which is one of the most abundant macromolecules of articular cartilage. However, it is not known if the PG molecule is citrullinated in vivo in human cartilage, and if so, whether citrulline-containing neoepitopes of PG (CitPG can contribute to autoimmunity in RA.CitPG was detected in human cartilage extracts using ACPA+ RA sera in dot blot and Western blot. Citrullination status of in vitro citrullinated recombinant G1 domain of human PG (rhG1 was confirmed by antibody-based and chemical methods, and potential sites of citrullination in rhG1 were explored by molecular modeling. CitPG-specific serum autoantibodies were quantified by enzyme-linked immunosorbent assays, and CitPG was localized in osteoarthritic (OA and RA cartilage using immunohistochemistry.Sera from ACPA+ RA patients reacted with PG purified from normal human cartilage specimens. PG fragments (mainly those containing the G1 domain from OA or RA cartilage extracts were recognized by ACPA+ sera but not by serum from ACPA- individuals. ACPA+ sera also reacted with in vitro citrullinated rhG1 and G3 domain-containing fragment(s of PG. Molecular modeling suggested multiple sites of potential citrullination within the G1 domain. The immunohistochemical localization of CitPG was different in OA and RA cartilage.CitPG is a new member of citrullinated proteins identified in human joints. CitPG could be found in

  5. Micro- and Nanomechanical Analysis of Articular Cartilage by Indentation-Type Atomic Force Microscopy: Validation with a Gel-Microfiber Composite

    OpenAIRE

    LOPARIC, Marko; Wirz, Dieter; Daniels, A. U.; Raiteri, Roberto; VanLandingham, Mark R.; Guex, Geraldine; Martin, Ivan; Aebi, Ueli; Stolz, Martin

    2010-01-01

    As documented previously, articular cartilage exhibits a scale-dependent dynamic stiffness when probed by indentation-type atomic force microscopy (IT-AFM). In this study, a micrometer-size spherical tip revealed an unimodal stiffness distribution (which we refer to as microstiffness), whereas probing articular cartilage with a nanometer-size pyramidal tip resulted in a bimodal nanostiffness distribution. We concluded that indentation of the cartilage's soft proteoglycan (PG) gel gave rise to...

  6. Vulnerability of the Superficial Zone of Immature Articular Cartilage to Compressive Injury

    Energy Technology Data Exchange (ETDEWEB)

    Rolauffs, R.; Muehleman, C; Li, J; Kurz, B; Kuettner, K; Frank, E; Grodzinsky, A

    2010-01-01

    The zonal composition and functioning of adult articular cartilage causes depth-dependent responses to compressive injury. In immature cartilage, shear and compressive moduli as well as collagen and sulfated glycosaminoglycan (sGAG) content also vary with depth. However, there is little understanding of the depth-dependent damage caused by injury. Since injury to immature knee joints most often causes articular cartilage lesions, this study was undertaken to characterize the zonal dependence of biomechanical, biochemical, and matrix-associated changes caused by compressive injury. Disks from the superficial and deeper zones of bovine calves were biomechanically characterized. Injury to the disks was achieved by applying a final strain of 50% compression at 100%/second, followed by biomechanical recharacterization. Tissue compaction upon injury as well as sGAG density, sGAG loss, and biosynthesis were measured. Collagen fiber orientation and matrix damage were assessed using histology, diffraction-enhanced x-ray imaging, and texture analysis. Injured superficial zone disks showed surface disruption, tissue compaction by 20.3 {+-} 4.3% (mean {+-} SEM), and immediate biomechanical impairment that was revealed by a mean {+-} SEM decrease in dynamic stiffness to 7.1 {+-} 3.3% of the value before injury and equilibrium moduli that were below the level of detection. Tissue areas that appeared intact on histology showed clear textural alterations. Injured deeper zone disks showed collagen crimping but remained undamaged and biomechanically intact. Superficial zone disks did not lose sGAG immediately after injury, but lost 17.8 {+-} 1.4% of sGAG after 48 hours; deeper zone disks lost only 2.8 {+-} 0.3% of sGAG content. Biomechanical impairment was associated primarily with structural damage. The soft superficial zone of immature cartilage is vulnerable to compressive injury, causing superficial matrix disruption, extensive compaction, and textural alteration, which results

  7. Expression Profiling and Functional Implications of a Set of Zinc Finger Proteins, ZNF423, ZNF470, ZNF521, and ZNF780B, in Primary Osteoarthritic Articular Chondrocytes

    Directory of Open Access Journals (Sweden)

    Maria Mesuraca

    2014-01-01

    Full Text Available Articular chondrocytes are responsible for the maintenance of healthy articulations; indeed, dysregulation of their functions, including the production of matrix proteins and matrix-remodeling proteases, may result in fraying of the tissue and development of osteoarthritis (OA. To explore transcriptional mechanisms that contribute to the regulation of chondrocyte homeostasis and may be implicated in OA development, we compared the gene expression profile of a set of zinc finger proteins potentially linked to the control of chondrocyte differentiation and/or functions (ZNF423, ZNF470, ZNF521, and ZNF780B in chondrocytes from patients affected by OA and from subjects not affected by OA. This analysis highlighted a significantly lower expression of the transcript encoding ZNF423 in chondrocytes from OA, particularly in elderly patients. Interestingly, this decrease was mirrored by the similarly reduced expression of PPARγ, a known target of ZNF423 with anti-inflammatory and chondroprotective properties. The ZNF521 mRNA instead was abundant in all primary chondrocytes studied; the RNAi-mediated silencing of this gene significantly altered the COL2A/COL1 expression ratio, associated with the maintenance of the differentiated phenotype, in chondrocytes cultivated in alginate beads. These results suggest a role for ZNF423 and ZNF521 in the regulation of chondrocyte homeostasis and warrant further investigations to elucidate their mechanism of action.

  8. 99mTc-labeled chondroitin sulfate-uptake by chondrocytes and cartilage. Potential agent for osteoarthritis imaging?

    International Nuclear Information System (INIS)

    Aim: Chondroitin sulfate (CS) is an endogenous component of cartilage proteoglycan which could monitor osteoarthritic cartilage degradation after radiolabeling. This substance is used in the treatment of human osteoarthritis as a slow acting symptomatic drug (CONDROSULF; Sanova Pharma, Vienna; Ibsa, Switzerland). Material and Methods: Radiolabeling of CS was performed using 99mTcO4-/stannous chloride in 0.50 M sodium acetate buffer at pH 5.0. The quality control of the tracer was performed using ITLC-SG chromatography and 0.2 M saline in 10% ethanol as solvent to detect colloid content. Aluminium oxide IB-F TLC-sheets and ethanol as solvent were used to estimate free pertechnetate. For uptake studies cultured human chondrocytes and age-matched cartilage were used. Uptake of the tracer in chondrocytes was studied in monolayer and in suspension cultures at 370C. Uptake was monitored for a total of 120-180 minutes, samples being drawn every 10 minutes. Because the commercially available drug Condrosulf contains calcium stearate as additive to improve the resorption of the drug, we investigated also the uptake with and without additive. Results: The tracer was stable over 6h period after labeling (95% of the radiochemical purity). In plasma the stability was lower amounting to 75%. Viability of chondrocytes after incubation with either CS-preparation was found by trypan blue exclusion to be above 95 %. Uptake of the tracer performed in monolayer ± additives was low and amounted to 0.5%±0.05%, n=6. The cells were saturated already after an incubation interval of 10 minutes. In suspension cultures a maximal uptake of 1.0%±0.1%, n=6 and 5.9%±0.65%, n=6 was found, without and with additives, respectively, the saturation was achieved after 100 min. Thus, not only the resorption of the drug is enhanced by Ca-stearate, but also uptake increases in presence of this additive. Using human rib cartilage the uptake of the tracer was much higher amounting to 4.9%±2.3%, n=6

  9. Fourier-transform infrared anisotropy in cross and parallel sections of tendon and articular cartilage

    Directory of Open Access Journals (Sweden)

    Bidthanapally Aruna

    2008-10-01

    Full Text Available Abstract Background Fourier Transform Infrared Imaging (FTIRI is used to investigate the amide anisotropies at different surfaces of a three-dimensional cartilage or tendon block. With the change in the polarization state of the incident infrared light, the resulting anisotropic behavior of the tissue structure is described here. Methods Thin sections (6 μm thick were obtained from three different surfaces of the canine tissue blocks and imaged at 6.25 μm pixel resolution. For each section, infrared imaging experiments were repeated thirteen times with the identical parameters except a 15° increment of the analyzer's angle in the 0° – 180° angular space. The anisotropies of amide I and amide II components were studied in order to probe the orientation of the collagen fibrils at different tissue surfaces. Results For tendon, the anisotropy of amide I and amide II components in parallel sections is comparable to that of regular sections; and tendon's cross sections show distinct, but weak anisotropic behavior for both the amide components. For articular cartilage, parallel sections in the superficial zone have the expected infrared anisotropy that is consistent with that of regular sections. The parallel sections in the radial zone, however, have a nearly isotropic amide II absorption and a distinct amide I anisotropy. Conclusion From the inconsistency in amide anisotropy between superficial to radial zone in parallel section results, a schematic model is used to explain the origins of these amide anisotropies in cartilage and tendon.

  10. Curcumin reduces prostaglandin E2, matrix metalloproteinase-3 and proteoglycan release in the secretome of interleukin 1β-treated articular cartilage [v1; ref status: indexed, http://f1000r.es/1cl

    Directory of Open Access Journals (Sweden)

    Abigail L Clutterbuck

    2013-07-01

    Full Text Available Objective: Curcumin (diferuloylmethane is a phytochemical with potent anti-inflammatory and anti-oxidant properties, and has therapeutic potential for the treatment of a range of inflammatory diseases, including osteoarthritis (OA. The aim of this study was to determine whether non-toxic concentrations of curcumin can reduce interleukin-1beta (IL-1β-stimulated inflammation and catabolism in an explant model of cartilage inflammation. Methods: Articular cartilage explants and primary chondrocytes were obtained from equine metacarpophalangeal joints. Curcumin was added to monolayer cultured primary chondrocytes and cartilage explants in concentrations ranging from 3μM-100μM. Prostaglandin E2 (PGE2 and matrix metalloproteinase (MMP-3 release into the secretome of IL-1β-stimulated explants was measured using a competitive ELISA and western blotting respectively. Proteoglycan (PG release in the secretome was measured using the 1,9-dimethylmethylene blue (DMMB assay. Cytotoxicity was assessed with a live/dead assay in monolayer cultures after 24 hours, 48 hours and five days, and in explants after five days. Results: Curcumin induced chondrocyte death in primary cultures (50μM p<0.001 and 100μM p<0.001 after 24 hours. After 48 hours and five days, curcumin (≥25μM significantly increased cell death (p<0.001 both time points. In explants, curcumin toxicity was not observed at concentrations up to and including 25μM after five days. Curcumin (≥3μM significantly reduced IL-1β-stimulated PG (p<0.05 and PGE2 release (p<0.001 from explants, whilst curcumin (≥12μM significantly reduced MMP-3 release (p<0.01. Conclusion: Non-cytotoxic concentrations of curcumin exert anti-catabolic and anti-inflammatory effects in cartilage explants.

  11. Curcumin reduces prostaglandin E2, matrix metalloproteinase-3 and proteoglycan release in the secretome of interleukin 1β-treated articular cartilage [v2; ref status: indexed, http://f1000r.es/1ks

    Directory of Open Access Journals (Sweden)

    Abigail L Clutterbuck

    2013-08-01

    Full Text Available Objective: Curcumin (diferuloylmethane is a phytochemical with potent anti-inflammatory and anti-oxidant properties, and has therapeutic potential for the treatment of a range of inflammatory diseases, including osteoarthritis (OA. The aim of this study was to determine whether non-toxic concentrations of curcumin can reduce interleukin-1beta (IL-1β-stimulated inflammation and catabolism in an explant model of cartilage inflammation. Methods: Articular cartilage explants and primary chondrocytes were obtained from equine metacarpophalangeal joints. Curcumin was added to monolayer cultured primary chondrocytes and cartilage explants in concentrations ranging from 3μM-100μM. Prostaglandin E2 (PGE2 and matrix metalloproteinase (MMP-3 release into the secretome of IL-1β-stimulated explants was measured using a competitive ELISA and western blotting respectively. Proteoglycan (PG release in the secretome was measured using the 1,9-dimethylmethylene blue (DMMB assay. Cytotoxicity was assessed with a live/dead assay in monolayer cultures after 24 hours, 48 hours and five days, and in explants after five days. Results: Curcumin induced chondrocyte death in primary cultures (50μM p<0.001 and 100μM p<0.001 after 24 hours. After 48 hours and five days, curcumin (≥25μM significantly increased cell death (p<0.001 both time points. In explants, curcumin toxicity was not observed at concentrations up to and including 25μM after five days. Curcumin (≥3μM significantly reduced IL-1β-stimulated PG (p<0.05 and PGE2 release (p<0.001 from explants, whilst curcumin (≥12μM significantly reduced MMP-3 release (p<0.01. Conclusion: Non-cytotoxic concentrations of curcumin exert anti-catabolic and anti-inflammatory effects in cartilage explants.

  12. The influence of collagen network integrity on the accumulation of gadolinium-based MR contrast agents in articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Wiener, Edzard; Schmidt, C.; Diederichs, G. [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie; Settles, M. [Klinikum rechts der Isar, Muenchen (Germany). Inst. fuer Roentgendiagnostik; Weirich, G. [Klinikum Rechts der Isar, Muenchen (Germany). Inst. fuer Pathologie und Pathologische Anatomie

    2011-03-15

    Delayed gadolinium-enhanced MR imaging of cartilage is used to quantify the proteoglycan loss in early osteoarthritis. It is assumed that T 1 after Gd-DTPA administration in the near equilibrium state reflects selective proteoglycan loss from cartilage. To investigate the influence of the collagen network integrity on contrast accumulation, the relaxation rates {delta}R1 and {delta}R2 were compared after Gd-DTPA administration in a well established model of osteoarthritis. Collagen or proteoglycan depletion was induced by the proteolytic enzymes papain and collagenase in healthy bovine patellar cartilage. Using a dedicated MRI sequence, T{sub 1} and T{sub 2} maps were simultaneously acquired before and 11 h after Gd-DTPA administration. Depth-dependent profiles of {delta}R1 and {delta}R2 were calculated in healthy, proteoglycan and collagen-depleted articular cartilage and the mean values of different cartilage layers were compared using the Mann-Whitney-U test. In superficial layers (1 mm) there was no significant difference (p > 0.05) in either {delta}R1 or {delta}R2 between proteoglycan-depleted (16.6 {+-} 1.2 s{sup -1}, 15.9 {+-} 1.0 s{sup -1}) and collagen-depleted articular cartilage (15.3 {+-} 0.9 s{sup -1}, 15.5 {+-} 0.9 s{sup -1}). In deep layers (3 mm) both parameters were significantly higher (p = 0.005, 0.03) in proteoglycan-depleted articular cartilage (12.3 {+-} 1.1 s{sup -1}, 9.8 {+-} 0.8 s{sup -1}) than in collagen-depleted articular cartilage (9.1 {+-} 1.1 s{sup -1}, 8.7 {+-} 0.7 s{sup -1}). Both proteoglycan loss and alterations in the collagen network influence the accumulation of Gd-DTPA in articular cartilage with significant differences between superficial and deep cartilage layers. (orig.)

  13. Effect of short-term enzymatic treatment on cell migration and cartilage regeneration: in vitro organ culture of bovine articular cartilage.

    Science.gov (United States)

    Seol, Dongrim; Yu, Yin; Choe, Hyeonghun; Jang, Keewoong; Brouillette, Marc J; Zheng, Hongjun; Lim, Tae-Hong; Buckwalter, Joseph A; Martin, James A

    2014-07-01

    Depending on the damage extent and adjacent tissue condition in traumatic cartilage injury, it is possible to heal the tissue by resident cells. Unlike autologous chondrocyte implantation, short-term enzymatic treatment is an effective single-step procedure without extra cell expansion. Moreover, this method has been shown to significantly increase cellularity in lesion edges, resulting in enhanced integration and interfacial strength. We hypothesize that the locally digested extracellular matrix by treatment allows effortless cell migration from the adjacent tissue. Full-thickness cartilage discs and osteochondral explants were prepared from mature bovine stifle joints. These specimens were treated with collagenase in a culture medium. Two concentrations, 0.25 and 0.5 mg/mL, were used with various treating time of 10, 30, and 180 min. The cartilages were subsequently washed and cultured with fibrin hydrogel. The effect of enzymatic treatment on cell migration was apparent in both experiments of the cartilage disc and full-thickness cartilage defect model. In the disc culture, the treatment resulted in an approximately three to four times higher number of migrated cells than nontreated control. In short-term collagenase-treated groups, the proteoglycan (PG) loss was localized in the edge of tissue with minimal cell death. The treatment also accelerated cell migration in the full-thickness cartilage defects and some cells differentiated into chondrocytes with the deposit of PG. Gene expression results could support the characteristics of migrated cells, which had migratory ability and chondrogenic differentiation potential with overexpression of collagen type I and II, respectively. Based on these results, short-term enzymatic treatment, which can accelerate cell migration into traumatically injured cartilage, has great potential for clinical application. PMID:24428547

  14. Oxygen tension affects lubricin expression in chondrocytes.

    Science.gov (United States)

    Hatta, Taku; Kishimoto, Koshi N; Okuno, Hiroshi; Itoi, Eiji

    2014-10-01

    We assessed the effects of oxygen tension on lubricin expression in bovine chondrocytes and cartilage explants and a role for hypoxia-inducible transcription factor (HIF)-1α in regulating lubricin expression was investigated using a murine chondroprogenitor cell line, ATDC5, and bovine chondrocytes isolated from superficial and middle/deep zones of femoral cartilage. ATDC5 cells and bovine chondrocytes were cultured in micromass under different oxygen tensions (21%, 5%, and 1%). ATDC5 cells and middle/deep zone chondrocytes that initially had low lubricin expression levels were also cultured with or without transforming growth factor (TGF)-β1. Quantitative reverse transcription (RT)-PCR was used to determine lubricin and chondrogenic marker gene mRNA levels and immunohistochemistry was used to assess lubricin protein expression. Explant cartilage plugs cultured under different oxygen tensions were also subjected to immunohistological analysis for lubricin. HIF-1α gene silencing was achieved by electroporatic transfer into ATDC5 cells. A low oxygen tension reduced lubricin gene expression levels in bovine superficial chondrocytes, TGF-β1-treated middle/deep zone chondrocytes, and TGF-β1-treated ATDC5 cells. Lubricin expression in explant cartilage was also suppressed under hypoxia. HIF-1α gene silencing in ATDC5 cells attenuated the lubricin expression response to the oxygen tension. These results corroborate with previous studies that the oxygen tension regulates lubricin gene expression and suggest that HIF-1α plays an important role in this regulation. The normal distribution of lubricin in articular cartilage may be due to the hypoxic oxygen environment of cartilage as it is an avascular tissue. An oxygen tension gradient may be a key factor for engineering cartilage tissue with a layered morphology. PMID:24712343

  15. Clinical Trial and In Vitro Study for the Role of Cartilage and Synovia in Acute Articular Infection

    DEFF Research Database (Denmark)

    Langenmair, E. R.; Kubosch, E. J.; Salzmann, G. M.;

    2015-01-01

    Objective. Osteoarthritis is a long-term complication of acute articular infections. However, the roles of cartilage and synovia in this process are not yet fully understood. Methods. Patients with acute joint infections were enrolled in a prospective clinical trial and the cytokine composition o...

  16. Variation in viscoelastic properties of bovine articular cartilage below, up to and above healthy gait-relevant loading frequencies

    OpenAIRE

    Sadeghi, Hamid; Espino, Daniel M; Shepherd, Duncan ET

    2015-01-01

    The aim of this study was to determine the variation in viscoelastic properties of femoral head bovine articular cartilage, on-bone, over five orders of magnitude of loading frequency. These frequencies ranged from below, up to and above healthy gait-relevant frequencies, using

  17. Reproducibility and accuracy of quantitative assessment of articular cartilage volume measurements with 3.0 tesla magnetic resonance imaging

    Institute of Scientific and Technical Information of China (English)

    XING Wei; SHENG Jing; CHEN Wen-hua; TIAN Jian-ming; ZHANG Li-rong; WANG Dong-qing

    2011-01-01

    Background Quantitative magnetic resonance imaging (qMRI) of articular cartilage represents a powerful tool in osteoarthritis research, but has so far been confined to a field strength of 1.5 T. The aim of the study was to determine the reproducibility and accuracy of qMRI assessments of the knee cartilage volume by comparing quantitative swine cartilage volumes of the sagittal (sag) multi echo data imagine combination water-excitation (MEDICwe) sequence and the fast low-angle shoot water-excitation (FLASHwe) sequence at 3.0-T MRI to directly measured volumes (DMV) of the surgically removed articular cartilage.Methods Test-retest MRI was acquired in 20 swine knees. Two sag FLASHwe sequences and two sag MEDICwe sequences (spatial resolution 0.4 mm × 0.4 mm × 1.0 mm of 3-dimension (3D) were acquired at 3-T MRI in a knee.Articular cartilage volume was calculated from 3D reformations of the MRI by using a manual program. Calculated volumes were compared with DMV of the surgically removed articular cartilage. Knee joint cartilage plates were quantified paired in order.Results In the knee joint of swine, reproducibility errors (paired analysis) for cartilage volume were 2.5% to 3.2% with sag FLASHwe, and 1.6% to 3.0% with sag MEDICwe. Correlation coefficients between results obtained with qMRI and DMV ranged from 0.90 to 0.98 for cartilage volume. Systematic pairwise difference between results obtained with qMRI and DMV ranged from -1.1% to 2.8%. Random pairwise differences between results obtained with qMRI and DMV ranged from (2.9 ±2.4)% to (6.8±4.5)%.Conclusions FLASHwe and MEDICwe sequences permit highly accurate and reproducible analysis of cartilage volume in the knee joints of swine at 3-T MRI. Cartilage volume reproducibility for the MEDICwe data is slightly higher than the FLASHwe data.

  18. Contraction-induced Mmp13 and-14 expression by goat articular chondrocytes in collagen type I but not type II gels

    NARCIS (Netherlands)

    Berendsen, Agnes D.; Vonk, Lucienne A.; Zandieh-Doulabi, Behrouz; Everts, Vincent; Bank, Ruud A.

    2012-01-01

    Collagen gels are promising scaffolds to prepare an implant for cartilage repair but several parameters, such as collagen concentration and composition as well as cell density, should be carefully considered, as they are reported to affect phenotypic aspects of chondrocytes. In this study we investi

  19. Saponin-rich fraction from Clematis chinensis Osbeck roots protects rabbit chondrocytes against nitric oxide-induced apoptosis via preventing mitochondria impairment and caspase-3 activation

    OpenAIRE

    Wu, Wenjun; Gao, Xinghua; Xu, Xianxiang; Luo, Yubin; Liu, Mei; Xia, Yufeng; Dai, Yue

    2012-01-01

    Our previous study reported that the saponin-rich fraction from Clematis chinensis Osbeck roots (SFC) could effectively alleviate experimental osteoarthritis induced by monosodium iodoacetate in rats through protecting articular cartilage and inhibiting local inflammation. The present study was performed to investigate the preventive effects of SFC on articular chondrocyte, and explore the underlying mechanisms. Primary rabbit chondrocytes were cultured and exposed to sodium nitroprusside (SN...

  20. Integrity of articular cartilage on T2 mapping associated with meniscal signal change

    International Nuclear Information System (INIS)

    Objective: The purpose of this study was to investigate the relationship between T2 relaxation values (T2 RVs) within the superficial zone of articular cartilage and different types of meniscal degeneration/tear. Materials and methods: A review of 310 consecutive knee MRIs which included an 8 echo T2 relaxation sequence, in patients referred for standard clinical indications, was performed independently and in blinded fashion by 2 observers. The posterior horns of the medial and lateral menisci were each evaluated and divided into 4 subgroups: Normal (control), Grade I/II meniscal signal, Grade III meniscal signal-simple tear (Grade III-S), and Grade III meniscal signal-complex tear (Grade III-C). After exclusion criteria were applied, the medial meniscal group consisted of 65 controls and 133 patients, while the lateral meniscal group consisted of 143 controls and 55 patients. T2 RVs were measured by an observer blinded to the clinical history and MRI grading. Measurements were obtained over the superficial zone of femoral and tibial articular cartilage adjacent to the center of the posterior horn of each meniscus to ensure consistency between measurements. Analysis of covariance adjusting for age and gender was used to compare T2 RVs between patients and controls. Results: T2 RVs were significantly increased in patients with Grade III-C meniscal tears compared to controls over the medial tibial plateau (MTP; p = 0.0001) and lateral tibial plateau (LTP; p = 0.0008). T2 RVs were not increased in patients with Grade III-C meniscal tears over the medial femoral condyle (MFC; p = 0.11) or lateral femoral condyle (LFC; p = 0.99). Grade I/II meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.15), LFC (p = 0.69), MTP (p = 0.42), or LTP (p = 0.50). Grade III-S meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.54), LFC (p = 0.43), MTP (p = 0.30), or LTP (p = 0.38). Conclusion: Grade III-C meniscal tears are associated with

  1. Integrity of articular cartilage on T2 mapping associated with meniscal signal change

    Energy Technology Data Exchange (ETDEWEB)

    Kai, Brian [Department of Radiology, University of British Columbia, UBC Hospital, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5 (Canada); Mann, Sumeer A. [Department of Radiology, University of Alberta, Walter Mackenzie Health Sciences Center, Edmonton, AB, T6G 2B7 (Canada); King, Chris [Department of Radiology, University of British Columbia, UBC Hospital, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5 (Canada); Forster, Bruce B., E-mail: bruce.forster@vch.ca [Department of Radiology, University of British Columbia, UBC Hospital, 2211 Wesbrook Mall, Vancouver, BC, V6T 2B5 (Canada)

    2011-09-15

    Objective: The purpose of this study was to investigate the relationship between T2 relaxation values (T2 RVs) within the superficial zone of articular cartilage and different types of meniscal degeneration/tear. Materials and methods: A review of 310 consecutive knee MRIs which included an 8 echo T2 relaxation sequence, in patients referred for standard clinical indications, was performed independently and in blinded fashion by 2 observers. The posterior horns of the medial and lateral menisci were each evaluated and divided into 4 subgroups: Normal (control), Grade I/II meniscal signal, Grade III meniscal signal-simple tear (Grade III-S), and Grade III meniscal signal-complex tear (Grade III-C). After exclusion criteria were applied, the medial meniscal group consisted of 65 controls and 133 patients, while the lateral meniscal group consisted of 143 controls and 55 patients. T2 RVs were measured by an observer blinded to the clinical history and MRI grading. Measurements were obtained over the superficial zone of femoral and tibial articular cartilage adjacent to the center of the posterior horn of each meniscus to ensure consistency between measurements. Analysis of covariance adjusting for age and gender was used to compare T2 RVs between patients and controls. Results: T2 RVs were significantly increased in patients with Grade III-C meniscal tears compared to controls over the medial tibial plateau (MTP; p = 0.0001) and lateral tibial plateau (LTP; p = 0.0008). T2 RVs were not increased in patients with Grade III-C meniscal tears over the medial femoral condyle (MFC; p = 0.11) or lateral femoral condyle (LFC; p = 0.99). Grade I/II meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.15), LFC (p = 0.69), MTP (p = 0.42), or LTP (p = 0.50). Grade III-S meniscal signal was not associated with elevated T2 RVs over the MFC (p = 0.54), LFC (p = 0.43), MTP (p = 0.30), or LTP (p = 0.38). Conclusion: Grade III-C meniscal tears are associated with

  2. Chondroptosis in alkaptonuric cartilage.

    Science.gov (United States)

    Millucci, Lia; Giorgetti, Giovanna; Viti, Cecilia; Ghezzi, Lorenzo; Gambassi, Silvia; Braconi, Daniela; Marzocchi, Barbara; Paffetti, Alessandro; Lupetti, Pietro; Bernardini, Giulia; Orlandini, Maurizio; Santucci, Annalisa

    2015-05-01

    Alkaptonuria (AKU) is a rare genetic disease that affects the entire joint. Current standard of treatment is palliative and little is known about AKU physiopathology. Chondroptosis, a peculiar type of cell death in cartilage, has been so far reported to occur in osteoarthritis, a rheumatic disease that shares some features with AKU. In the present work, we wanted to assess if chondroptosis might also occur in AKU. Electron microscopy was used to detect the morphological changes of chondrocytes in damaged cartilage distinguishing apoptosis from its variant termed chondroptosis. We adopted histological observation together with Scanning Electron Microscopy and Transmission Electron Microscopy to evaluate morphological cell changes in AKU chondrocytes. Lipid peroxidation in AKU cartilage was detected by fluorescence microscopy. Using the above-mentioned techniques, we performed a morphological analysis and assessed that AKU chondrocytes undergo phenotypic changes and lipid oxidation, resulting in a progressive loss of articular cartilage structure and function, showing typical features of chondroptosis. To the best of our knowledge, AKU is the second chronic pathology, following osteoarthritis, where chondroptosis has been documented. Our results indicate that Golgi complex plays an important role in the apoptotic process of AKU chondrocytes and suggest a contribution of chondroptosis in AKU pathogenesis. These findings also confirm a similarity between osteoarthritis and AKU. PMID:25336110

  3. Chondrogenic differentiation of mouse embryonic stem cells promoted by mature chondrocytes

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to direct embryonic stem (ES) cells to differentiate into chondrocytes, a chondrogenic envi-ronment provided by mature chondrocytes was investigated. Flk-1 positive cells sorted from pre-differentiated mouse ES cells were mixed with adult porcine articular chondrocytes, seeded on biodegradable scaffolds, and then implanted subcutaneously into nude mice. The cell-scaffold com-plexes formed cartilage tissues after 4 weeks, which was demonstrated by histology and anti-type II collagen antibody staining. Positive staining of mouse Major Histocompatibility Complex class I molecules confirmed that part of the chondrocytes were derived from mouse ES cells. The current study established a new approach for directing ES cell differentiation.

  4. Proteomic and redox-proteomic evaluation of homogentisic acid and ascorbic acid effects on human articular chondrocytes.

    Science.gov (United States)

    Braconi, Daniela; Laschi, Marcella; Taylor, Adam M; Bernardini, Giulia; Spreafico, Adriano; Tinti, Laura; Gallagher, James A; Santucci, Annalisa

    2010-11-01

    Alkaptonuria (AKU) is a rare genetic disease associated with the accumulation of homogentisic acid (HGA) and its oxidized/polymerized products in connective tissues up to the deposition of melanin-like pigments (ochronosis). Since little is known on the effects of HGA and its metabolites on articular cells, we carried out a proteomic and redox-proteomic analysis to investigate how HGA and ascorbic acid (ASC) affect the human chondrocytic protein repertoire. We settled up an in vitro model using a human chondrocytic cell line to evaluate the effects of 0.33 mM HGA, alone or combined with ASC. We found that HGA and ASC significantly affect the levels of proteins with specific functions in protein folding, cell organization and, notably, stress response and cell defense. Increased protein carbonyls levels were found either in HGA or ASC treated cells, and evidences produced in this paper support the hypothesis that HGA-induced stress might be mediated by protein oxidation. Our finding can lay the basis towards the settling up of more sophisticated models to study AKU and ochronosis. PMID:20665660

  5. Influence of cytochalasin D-induced changes in cell shape on proteoglycan synthesis by cultured articular chondrocytes

    International Nuclear Information System (INIS)

    There is growing evidence that cell shape regulates both proliferation and differentiated gene expression in a variety of cell types. The authors have explored the relationship between the morphology of articular chondrocytes in culture and the amount and type of proteoglycan they synthesize, using cytochalasin D to induce reversible cell rounding. When chondrocytes were prevented from spreading or when spread cells were induced to round up, 35SO4 incorporation into proteoglycan was stimulated. Incorporation into the cell layer was stimulated more than into the medium. When the cells were allowed to respread by removing cytochalasin D, proteoglycan synthesis returned to control levels. Cytochalasin D-induced stimulation of 35SO4 incorporation reflected an increase in core protein synthesis rather than lengthening of glycosaminoglycan chains, because [3H]serine incorporation into core protein was also stimulated. Cytochalasm D-treatment of cells in suspension caused no further stimulation of 35SO4 incorporation, suggesting that the observed effects were due to cell rounding rather than exposure to cytochalasin D per se

  6. Age-related decrease in the responsiveness of rat articular chondrocytes to EGF is associated with diminished number and affinity for the ligand of cell surface binding sites.

    Science.gov (United States)

    Ribault, D; Habib, M; Abdel-Majid, K; Barbara, A; Mitrovic, D

    1998-01-12

    The effect of age on the responsiveness of articular chondrocytes (AC) to epidermal growth factor (EGF) was examined. Cells were isolated by digesting cartilage fragments from the humeral and femoral heads of 21-day old, 8- and 14-month old rats with collagenase. The cells were cultured under standard conditions, as monolayers. DNA synthesis was measured by [3H]thymidine incorporation and cell proliferation by the DNA content of subconfluent cultures. [125I]EGF binding and the amounts of EGF and EGF-receptor mRNAs were determined using confluent cells. DNA synthesis was decreased with age of animals. EGF stimulated DNA synthesis in cultures in 1- and 8-month old rats at low serum concentrations (< 5%), and in cultures in 14-month old animals at high serum concentrations. It also increased 5-day DNA content of cultures compared to serum-treated controls but this effect was weak in cultures in 14-month old rats. The number of high affinity binding sites for [125I]EGF decreased from 37,800 in the 1-month old to 1950 in the 14-month old rat AC. The apparent dissociation constant (Kd) also decreased with age: 0.18 nmol/l in the 1-month old; 0.12 nmol/l in the 8-month old; and 0.07 nmol/l in the 14-month old cells. AC in older rats contained more EGF mRNA and less EGF-receptor mRNA. Incubation of the cells with EGF resulted in down regulation of the EGF- and upregulation of EGF-receptor mRNA expressions. These findings show the age-related quantitative and qualitative alterations in EGF and EGF-receptor which may account, at least in part, for the diminished responsiveness of senescent AC to EGF. PMID:9509392

  7. Gene expression profile of the cartilage tissue spontaneously regenerated in vivo by using a novel double-network gel: Comparisons with the normal articular cartilage

    Directory of Open Access Journals (Sweden)

    Kurokawa Takayuki

    2011-09-01

    Full Text Available Abstract Background We have recently found a phenomenon that spontaneous regeneration of a hyaline cartilage-like tissue can be induced in a large osteochondral defect by implanting a double-network (DN hydrogel plug, which was composed of poly-(2-Acrylamido-2-methylpropanesulfonic acid and poly-(N, N'-Dimetyl acrylamide, at the bottom of the defect. The purpose of this study was to clarify gene expression profile of the regenerated tissue in comparison with that of the normal articular cartilage. Methods We created a cylindrical osteochondral defect in the rabbit femoral grooves. Then, we implanted the DN gel plug at the bottom of the defect. At 2 and 4 weeks after surgery, the regenerated tissue was analyzed using DNA microarray and immunohistochemical examinations. Results The gene expression profiles of the regenerated tissues were macroscopically similar to the normal cartilage, but showed some minor differences. The expression degree of COL2A1, COL1A2, COL10A1, DCN, FMOD, SPARC, FLOD2, CHAD, CTGF, and COMP genes was greater in the regenerated tissue than in the normal cartilage. The top 30 genes that expressed 5 times or more in the regenerated tissue as compared with the normal cartilage included type-2 collagen, type-10 collagen, FN, vimentin, COMP, EF1alpha, TFCP2, and GAPDH genes. Conclusions The tissue regenerated by using the DN gel was genetically similar but not completely identical to articular cartilage. The genetic data shown in this study are useful for future studies to identify specific genes involved in spontaneous cartilage regeneration.

  8. MRI properties of a unique hypo-intense layer in degraded articular cartilage

    Science.gov (United States)

    Wang, Nian; Badar, Farid; Xia, Yang

    2015-11-01

    To investigate the characteristics of a hypo-intense laminar appearance in articular cartilage under external loading, microscopic magnetic resonance imaging (μMRI) T1, T2 and T1ρ experiments of a total of 15 specimens of healthy and trypsin-degraded cartilage were performed at different soaking solutions (saline and 100 mM phosphate buffered saline (PBS)). T2 and T1ρ images of the healthy tissue in saline showed no load-induced laminar appearance, while a hypo-intense layer was clearly visible in the deep part of the degraded tissue at the magic angle. A significant difference was found between T2 values at 0° and 55° (from 16.5  ±  2.8 ms to 20.2  ±  2.7 ms, p  =  0.0005), and at 0° and 90° (16.5  ±  2.8 ms to 21.3  ±  2.6 ms, p  <  0.0001) in saline solution. In contrast, this hypo-intense laminar appearance largely disappeared when tissue was soaked in PBS. The visualization of this hypo-intensity appearance in different soaking mediums calls for caution in interpreting the data of relaxation times, chemical exchange and collagen fiber deformation.

  9. MR evaluation of the articular cartilage of the femoral head during traction. Correlation with resected femoral head

    Energy Technology Data Exchange (ETDEWEB)

    Nakanishi, K. [Osaka Seamens Insurance Hospital (Japan). Dept. of Radiology; Tanaka, H.; Narumi, Y.; Nakamura, H. [Osaka Univ. Medical School (Japan). Dept. of Radiology; Nishii, T.; Masuhara, K. [Osaka Univ. Medical School (Japan). Dept. of Orthopedic Surgery

    1999-01-01

    Objective: The purpose was to evaluate the articular cartilage of the hip joint with MR during traction and compare the findings with the resected specimen or arthroscopic findings. Material and Methods: Eight healthy volunteers, 5 patients with osteonecrosis, 5 with acetabular dysplasia, and 5 with advanced osteoarthrosis underwent MR imaging to evaluate the articular cartilage of the hip joint. Coronal fat-suppressed 3D spoiled gradient-echo (SPGR) images were obtained during traction. Identical imaging was performed of all the resected femoral heads of the osteonecrosis and advanced osteoarthrosis patients, and was correlated with the macroscopic pathological findings. Results: The traction was effective and the femoral articular cartilage was clearly identified in all 8 control subjects, and in all cases of osteonecrosis and acetabular dysplasia. In 4 cases of osteonecrosis, chondral fracture was identified in the boundary between the necrosis and the normal area. In all cases of advanced osteoarthrosis, cartilage was identified only at the medial side. The MR images of osteonecrosis and advanced osteoarthrosis corresponded well with the MR images of the resected femoral heads and the macroscopic findings. (orig.)

  10. The collagen structure of equine articular cartilage characterized using polarization-sensitive optical coherence tomography and non-linear microscopy

    Science.gov (United States)

    Mansfield, Jessica C.; Ugryumova, Nadya; Knapp, Karen M.; Matcher, Stephen J.

    2006-09-01

    Equine articular cartilage has been imaged using both polarization-sensitive optical coherence tomography (PS-OCT) and non-linear microscopy. PS-OCT has been used to spatially map the birefringence in the cartilage and we have found that in the vicinity of the lesion the images display a characteristic disruption in the regular birefringence bands shown by normal cartilage. We also note that significant (e.g. x2) variations in the apparent birefringence of samples taken from young (18 month) animals that otherwise appear visually homogeneous are found over spatial scales of a few millimeters. We have also imaged the cartilage using non-linear microscopy and compare the scans taken with second harmonic generation (SHG) light and the two photon fluorescence (TPF) light. SHG images collected using 800 nm excitation reveals the spatial distribution of collagen fibers, whilst TPF images clearly shows the distribution of intracellular and pericellular fluorophores.

  11. A novel fibroblast growth factor receptor 1 inhibitor protects against cartilage degradation in a murine model of osteoarthritis

    Science.gov (United States)

    Xu, Wei; Xie, Yangli; Wang, Quan; Wang, Xiaofeng; Luo, Fengtao; Zhou, Siru; Wang, Zuqiang; Huang, Junlan; Tan, Qiaoyan; Jin, Min; Qi, Huabing; Tang, Junzhou; Chen, Liang; Du, Xiaolan; Zhao, Chengguang; Liang, Guang; Chen, Lin

    2016-01-01

    The attenuated degradation of articular cartilage by cartilage-specific deletion of fibroblast growth factor receptor 1 (FGFR1) in adult mice suggests that FGFR1 is a potential target for treating osteoarthritis (OA). The goal of the current study was to investigate the effect of a novel non-ATP-competitive FGFR1 inhibitor, G141, on the catabolic events in human articular chondrocytes and cartilage explants and on the progression of cartilage degradation in a murine model of OA. G141 was screened and identified via cell-free kinase-inhibition assay. In the in vitro study, G141 decreased the mRNA levels of catabolic markers ADAMTS-5 and MMP-13, the phosphorylation of Erk1/2, JNK and p38 MAPK, and the protein level of MMP-13 in human articular chondrocytes. In the ex vivo study, proteoglycan loss was markedly reduced in G141 treated human cartilage explants. For the in vivo study, intra-articular injection of G141 attenuated the surgical destabilization of the medial meniscus (DMM) induced cartilage destruction and chondrocyte hypertrophy and apoptosis in mice. Our data suggest that pharmacologically antagonize FGFR1 using G141 protects articular cartilage from osteoarthritic changes, and intra-articular injection of G141 is potentially an effective therapy to alleviate OA progression. PMID:27041213

  12. A biochemical model for characterising the surface-active phospolipid bilayer of articular cartilage relative to acid-base equilibrium

    Directory of Open Access Journals (Sweden)

    Z. Pawlak

    2008-01-01

    Full Text Available Purpose: This paper, addresses the question of how changes in acid - base equilibrium influence change in thecharge density of the phospholipid bilayer on articular cartilage surfaces during lubrication.Design/methodology/approach: Liposomes have been used to mimic biological phospholipid membranes onarticular cartilage surface where proteins are bounded, ions are transported, energy is transducted, and cellular processestake place. The charge density of the membrane was determined as a function of pH and electrolyte concentration fromthe microelectrophoretic method. Liposome membrane was prepared as an aqueous solution of NaCl under variouspH conditions. Microelectrophoresis was used to examine the local acid-base equilibrium of the electrolytes with themembrane surface, which can be considered to model the phospholipids interface in articular cartilage.Findings: The adsorbed ions (H+, OH-, Na+, Cl- which are present in the electrically charged solutions of liposomemembrane comprising phosphatidycholine (PC, were found to exhibit pH-responsive quasi-periodic behavior.Research limitations/implications: We have established that the acid-base dissociation behavior inphospholipid bilayers of articular cartilage is a key to understanding biolubrication processes. For example,previous investigators found that the formation of the multilayer of polyisopeptide/hyaluronic acid depends onsurface properties such as film thickness, surface friction, surface wetability; wetness and swelling behavior.Future work should consider the adsorption of polyelectrolyte ions, e.g., the glycoprotein lubricin and hyaluronan,on the liposome membrane surface in the presence of H+ and OH- ions.Originality/value: A novel model of the joints’ phospholipid bilayers has been created using liposome membraneThis model can be applied in the investigation of polyelectrolyte ions such as lubricin, in articular cartilage. Wehave demonstrated that the acid-base processes on

  13. Delayed Gadolinium-Enhanced Magnetic Resonance Imaging (dGEMRIC) of Hip Joint Cartilage: Better Cartilage Delineation after Intra-Articular than Intravenous Gadolinium Injection

    International Nuclear Information System (INIS)

    Purpose: To investigate and compare delayed gadolinium (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in the hip joint using intravenous (i.v.) or ultrasound-guided intra-articular (i.a.) Gd-DTPA injection. Material and Methods: In 10 patients (50% males, mean age 58 years) with clinical and radiographic hip osteoarthritis (OA; Kellgren score II-III), MRI of the hip was performed twice on a clinical 1.5T MR scanner: On day 1, before and 90-180 min after 0.3 mmol/kg body weight i.v. Gd-DTPA and, on day 8, 90-180 min after ultrasound-guided i.a. injection of a 4 mmol/l Gd-DTPA solution. Coronal STIR, coronal T1 fat-saturated spin-echo, and a cartilage-sensitive gradient-echo sequence (3D T1 SPGR) in the sagittal plane were applied. Results: Both the post-i.v. and post-i.a. Gd-DTPA images showed significantly higher signal-to-noise (SNR) and contrast-to-noise (CNR) in the joint cartilage compared to the non-enhanced images ( P <0.002). I.a. Gd-DTPA provided significantly higher SNR and CNR compared to i.v. Gd-DTPA ( P <0.01). Furthermore, a better delineation of the cartilage in the synovial/cartilage zone and of the chondral/subchondral border was observed. Conclusion: The dGEMRIC MRI method markedly improved delineation of hip joint cartilage compared to non-enhanced MRI. The i.a. Gd-DTPA provided the best cartilage delineation. dGEMRIC is a clinically applicable MRI method that may improve identification of early subtle cartilage damage and the accuracy of volume measurements of hip joint cartilage

  14. Effect of low-energy shock waves in microfracture holes in the repair of articular cartilage defects in a rabbit model

    Institute of Scientific and Technical Information of China (English)

    WANG Qi; LI Zhong-li; FU Yang-mu; WANG Zhi-gang; WEI Min; ZHAO Bin; ZHANG Li; ZHU Juan-li

    2011-01-01

    Background Microfracture is a type of bone marrow stimulation in arthroscopic cartilage repair. However, the overall concentration of the mesenchymal stem cells is quite low and declines with age, and in the end the lesion is filled by fibrocartilage. The aim of this research was to investigate a novel method of enhancing microfracture by determining whether low-energy shock waves in microfracture holes would facilitate cartilage repair in a rabbit model.Methods Full-thickness cartilage defects were created at the medial femoral condyle of 36 mature New Zealand white rabbits without penetrating subchondral bone. The rabbits were randomly divided into three groups. In experimental group A, low-energy shock-wave therapy was performed in microfracture holes (diameter, 1 mm) at an energy flux density (EFD) of 0.095 m J/mm2 and 200 impulses by DolorClast Master (Electro Medical Systems SA, Switzerland)microprobe (diameter, 0.8 mm). In experimental group B, microfracture was performed alone. The untreated rabbits served as a control group. At 4, 8, and 12 weeks after the operations, repair tissues at the defects were analyzed stereologically, histologically, and immunohistochemically.Results The defects were filled gradually with repair tissues in experimental groups A and B, and no repair tissues had formed in the control group at 12 weeks. Repair tissues in experimental group A contained more chondrocytes,proteoglycans, and collagen type Ⅱ than those in experimental group B. In experimental group B, fibrous tissues had formed at the defects at 8 and 12 weeks. Histological analysis of experimental group A showed a better Wakitani score (P <0.05) than in experimental group B at 8 and 12 weeks after the operation.Conclusions In the repair of full-thickness articular cartilage defects in rabbits, low-energy shock waves in microfracture holes facilitated the production of hyaline-like cartilage repair tissues more than microfracture alone. This model demonstrates a new

  15. A large-molecular-weight polyanion, synthesized via ring-opening metathesis polymerization, as a lubricant for human articular cartilage.

    Science.gov (United States)

    Wathier, Michel; Lakin, Benjamin A; Bansal, Prashant N; Stoddart, Stephanie S; Snyder, Brian D; Grinstaff, Mark W

    2013-04-01

    A large-molecular-weight polyanion is found to possess lubricating properties for cartilage. The polyanion, sodium poly(7-oxanorbornene-2-carboxylate), is synthesized by ring-opening metathesis polymerization of methyl 5-oxanorbornene-2-carboxylate. When dissolved in aqueous solution and applied to the surface of human cartilage it reduces the friction at the interface and acts as a lubricant. Its performance is similar to that of synovial fluid and superior to those of saline and Synvisc in an ex vivo human cartilage plug-on-plug model. The polymer is also not readily degraded by hyaluronidase or cytotoxic to human chondrocytes in vitro. As such, this polymer is a new type of viscosupplement, and the results provide insight into the design requirements for synthesizing highly efficacious synthetic biolubricants. PMID:23496043

  16. Specificity of Fourier Transform Infrared (FTIR) Microspectroscopy to Estimate Depth-Wise Proteoglycan Content in Normal and Osteoarthritic Human Articular Cartilage

    OpenAIRE

    Saarakkala, Simo; Julkunen, Petro

    2010-01-01

    Background: Fourier transform infrared (FTIR) microspectroscopy is a promising method for estimating the depth-wise composition of articular cartilage. The aim was to compare the specificity of two earlier introduced, presumably proteoglycan (PG)–specific FTIR parameters (i.e., absorption in the carbohydrate region with and without normalization with Amide I absorption) to estimate the reference PG content of normal and osteoarthritic human articular cartilage. This study is a direct continua...

  17. The Effect of Negative Poisson’s Ratio Polyurethane Scaffolds for Articular Cartilage Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Yeong Jun Park

    2013-01-01

    Full Text Available An auxetic polyurethane (PU scaffold was prepared to investigate chondrocyte proliferation under compressive stimulation for cartilage regeneration. To give a negative Poisson’s ratio to the PU scaffold, volumetric compression with a 3 : 1 ratio was applied during heat treatment. For the control PU scaffold, the Poisson’s ratio was 0.9 ± 0.25 with elongation at 20% of the strain range. Poisson’s ratio for experimental specimens was approximately −0.4 ± 0.12 under the same conditions. In cell proliferation tests, cells were cultivated within the prepared scaffold under compression with a 20% strain range. With a 20% strain range elongation, the compressive load was approximately 0.3 N. The experimental group showed a 1.3 times higher cellular proliferation rate than that of the control group after 3 days in culture. At day 5 of culture, however, the rate of proliferation of the control group increased so that there was no significant difference between groups. However, collagen content (produced by the cells in the cell-proliferated medium was 1.5 times higher in the experimental group after 5 days in culture. This may have been due to the effectiveness of the auxetic structure of the scaffold. An isotropic compressive load was transmitted to the cells due to the negative Poisson ratio of the scaffold.

  18. Measurement of articular cartilage volumes in the normal knee by magnetic resonance imaging. Can cartilage volumes be estimated from physical characteristics?

    International Nuclear Information System (INIS)

    In recent times several studies have been performed on magnetic resonance imaging (MRI) sequences for imaging cartilage. A fat-suppressed three-dimensional sequence is one such noteworthy example. More recent studies have reported that the total volume of cartilage in a knee joint can be elucidated using this sequence. Based on these studies, we hypothesized that the total volume of cartilage in the knee joint may reflect certain other physical characteristics. The purpose of the current study was to clarify the articular cartilage volumes of the patella and femur in the human knee joints of healthy adults using MRI and to analyze the correlation of these volumes with other physical characteristics. The material comprised 68 knees of 68 Japanese healthy volunteers, aged from their twenties to their forties (37 men and 31 women) who had no past history of joint disease or trauma in the legs. The knees were imaged by MRI with a fat-suppressed three-dimensional sequence, and the cartilage volumes were calculated by computer processing. The factors analyzed were age, body weight, height, leg length, foot size, circumferences of the thigh and lower leg, the distance between medial and lateral femoral condyles, the diameter of the tibial head, body mass index, general joint laxity, quadriceps angle, and leg-heel alignment. The mean cartilage volume was 7.6±1.6 cm3 (8.3±1.6 cm3 in men, 6.7±0.9 cm3 in women). It was significantly larger in men than in women. However, the volume positively correlated with body weight, height, leg length, and foot size, without distinction of gender or age. Based on these data, a multiple regression analysis was developed: cartilage volume 0.113 x height-11.053. We concluded that the cartilage volume depends on physical size regardless of gender, and it can be estimated from factors of physical size. (author)

  19. A novel computational modelling to describe the anisotropic, remodelling and reorientation behaviour of collagen fibrres in articular cartilage

    CERN Document Server

    Cortez, S; Alves, J L

    2016-01-01

    In articular cartilage the orientation of collagen fibres is not uniform, varying mostly with the depth on the tissue. Besides, the biomechanical response of each layer of the articular cartilage differs from the neighbouring ones, evolving through thickness as a function of the distribution, density and orientation of the collagen fibres. Based on a finite element implementation, a new continuum formulation is proposed to describe the remodelling and reorientation of the collagen fibres under arbitrary mechanical loads: the cartilaginous tissue is modelled based on a hyperelastic formulation, being the ground isotropic matrix described by a neo-Hookean law and the fibrillar anisotropic part modelled by a new anisotropic formulation introduced for the first time in the present work, in which both reorientation and remodelling are taken into account. To characterize the orientation of fibres, a structure tensor is defined to represent the expected distribution and orientation of fibres around a reference direc...

  20. Effects of non-steroidal anti-inflammatory drugs on cell proliferation and death in cultured epiphyseal-articular chondrocytes of fetal rats

    International Nuclear Information System (INIS)

    Previous reports indicated that non-steroidal anti-inflammatory drugs (NSAIDs) suppress bone repair. Our previous study further found that ketorolac delayed the endochondral bone formation, and the critical effective timing was at the early stage of repair. Furthermore, we found that NSAIDs suppressed proliferation and induced cell death of cultured osteoblasts. In this study, we hypothesized that chondrocytic proliferation and death, which plays an important role at the early stage of endochondral bone formation, might be affected by NSAIDs. Non-selective NSAIDs, indomethacin, ketorolac, diclofenac and piroxicam; cyclooxygenase-2 (COX-2) selective NSAIDs, celecoxib and DFU (an analog of rofecoxib); prostaglandins (PGs), PGE1, PGE2 and PGF2α; and each NSAID plus each PG were tested. The effects of NSAIDs on proliferation, cell cycle kinetics, cytotoxicity and cell death of epiphyseal-articular chondrocytes of fetal rats were examined. The results showed that all the tested NSAIDs, except DFU, inhibited thymidine incorporation of chondrocytes at a concentration range (10-8 to 10-4 M) covering the theoretic therapeutic concentrations. Cell cycle was arrested by NSAIDs at the G /G1 phase. Upon a 24 h treatment, LDH leakage and cell death (both apoptosis and necrosis) were significantly induced by the four non-selective NSAIDs in chondrocyte cultures. However, COX-2 inhibitors revealed non-significant effects on cytotoxicity of chondrocytes except higher concentration of celecoxib (10-4 M). Replenishments of PGE1, PGE2 or PGF2α could not reverse the effects of NSAIDs on chondrocytic proliferation and cytotoxicity. In this study, we found that therapeutic concentrations of non-selective NSAIDs caused proliferation suppression and cell death of chondrocytes, suggesting these adverse effects may be one of the reasons that NSAIDs delay the endochondral ossification during bone repair found in previous studies. Furthermore, these effects of NSAIDs may act via PG

  1. Engineering Cartilage

    Science.gov (United States)

    ... Research Matters NIH Research Matters March 3, 2014 Engineering Cartilage Artistic rendering of human stem cells on ... situations has been a major goal in tissue engineering. Cartilage contains water, collagen, proteoglycans, and chondrocytes. Collagens ...

  2. Variations in radiographic appearance of articular cartilage of knee joints in persons of 35 to 65 years of age

    OpenAIRE

    Himani Pulivarthi; Vasantha Maddikunta; P. Koteswara Rao

    2015-01-01

    Background: Osteoarthritis is a slowly progressive degenerative disease characterized by gradual loss of articular cartilage. Osteoarthritis is not a normal process of ageing processes. Age related changes are distinct from osteoarthritic changes but when coupled with certain precipitating factors like obesity, muscle weakness and neurological dysfunction may play an important role in the causation of osteoarthritis. Osteoarthritis occurrence appears to increase with patient's age in a non-li...

  3. Experimental articular cartilage repair in the Göttingen minipig: the influence of multiple defects per knee

    OpenAIRE

    Christensen, Bjørn Borsøe; Foldager, Casper Bindzus; Olesen, Morten Lykke; Vingtoft, Louise; Rölfing, Jan Hendrik Duedal; Ringgaard, Steffen; Lind, Martin

    2015-01-01

    Background A gold standard treatment for articular cartilage injuries is yet to be found, and a cost-effective and predictable large animal model is needed to bridge the gap between in vitro studies and clinical studies. Ideally, the animal model should allow for testing of clinically relevant treatments and the biological response should be reproducible and comparable to humans. This allows for a reliable translation of results to clinical studies.This study aimed at verifying the Göttingen ...

  4. A fibrin/hyaluronic acid hydrogel for the delivery of mesenchymal stem cells and potential for articular cartilage repair

    OpenAIRE

    Snyder, Timothy N; Madhavan, Krishna; Intrator, Miranda; Dregalla, Ryan C.; Park, Daewon

    2014-01-01

    Background Osteoarthritis (OA) is a degenerative joint disease affecting approximately 27 million Americans, and even more worldwide. OA is characterized by degeneration of subchondral bone and articular cartilage. In this study, a chondrogenic fibrin/hyaluronic acid (HA)-based hydrogel seeded with bone marrow-derived mesenchymal stem cells (BMSCs) was investigated as a method of regenerating these tissues for OA therapy. This chondrogenic hydrogel system can be delivered in a minimally invas...

  5. Low-Frequency High-Magnitude Mechanical Strain of Articular Chondrocytes Activates p38 MAPK and Induces Phenotypic Changes Associated with Osteoarthritis and Pain

    Directory of Open Access Journals (Sweden)

    Derek H. Rosenzweig

    2014-08-01

    Full Text Available Osteoarthritis (OA is a debilitating joint disorder resulting from an incompletely understood combination of mechanical, biological, and biochemical processes. OA is often accompanied by inflammation and pain, whereby cytokines associated with chronic OA can up-regulate expression of neurotrophic factors such as nerve growth factor (NGF. Several studies suggest a role for cytokines and NGF in OA pain, however the effects of changing mechanical properties in OA tissue on chondrocyte metabolism remain unclear. Here, we used high-extension silicone rubber membranes to examine if high mechanical strain (HMS of primary articular chondrocytes increases inflammatory gene expression and promotes neurotrophic factor release. HMS cultured chondrocytes displayed up-regulated NGF, TNFα and ADAMTS4 gene expression while decreasing TLR2 expression, as compared to static controls. HMS culture increased p38 MAPK activity compared to static controls. Conditioned medium from HMS dynamic cultures, but not static cultures, induced significant neurite sprouting in PC12 cells. The increased neurite sprouting was accompanied by consistent increases in PC12 cell death. Low-frequency high-magnitude mechanical strain of primary articular chondrocytes in vitro drives factor secretion associated with degenerative joint disease and joint pain. This study provides evidence for a direct link between cellular strain, secretory factors, neo-innervation, and pain in OA pathology.

  6. Type II and VI collagen in nasal and articular cartilage and the effect of IL-1 alpha on the distribution of these collagens

    NARCIS (Netherlands)

    I.D.C. Jansen; A.P. Hollander; D.J. Buttle; V. Everts

    2010-01-01

    The distribution of type II and VI collagen was immunocytochemically investigated in bovine articular and nasal cartilage. Cartilage explants were used either fresh or cultured for up to 4 weeks with or without interleukin 1α (IL-1α). Sections of the explants were incubated with antibodies for both

  7. Effects of mesenchymal stem cells on interleukin-1β-treated chondrocytes and cartilage in a rat osteoarthritic model.

    Science.gov (United States)

    Tang, Jilei; Cui, Weiding; Song, Fanglong; Zhai, Chenjun; Hu, Hansheng; Zuo, Qiang; Fan, Weimin

    2015-08-01

    In the present study, the effects and mechanisms of mesenchymal stem cells (MSCs) on interleukin (IL)-1β-stimulated rat chondrocytes, as well as cartilage from a rat model of osteoarthritis (OA) induced by anterior cruciate ligament transection and medial meniscectomy were investigated. Confluent rat chondrocytes were treated with IL-1β (10 ng/ml), then cultured indirectly with or without MSCs at a ratio of 2:1. Total RNA and protein were collected at various time-points, and western blot and reverse transcription-quantitative polymerase chain reaction analyses were used to investigate the expression of type II collagen (Col2), aggrecan, matrix metalloproteinase-13 (MMP-13) and cyclooxygenase-2 (COX-2). The activation of extracellular signal-regulated kinases 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB) p65 and inhibitory-κ-B-α (IκBα) were also assessed by western blotting. In addition, the in vivo effects of MSCs in a rat OA model were assessed by histology and western blot analysis. The results indicated that in vitro, IL-1β markedly upregulated the expression of MMP-13, COX-2, phosphorylated ERK1/2, JNK, p38 MAPK and NF-κB p65, and inhibited the expression of Col2, aggrecan and IκBα. Conversely, MSCs enhanced the expression of Col2, aggrecan and IκBα, and inhibited the expression of MMP-13 and NF-κB p65 in IL-1β-stimulated rat chondrocytes. In vivo histological and western blot analyses revealed analogous results to the in vitro findings. The results of the present study demonstrated that MSCs suppressed the inflammatory response and extracellular matrix degradation in IL-1β‑induced rat chondrocytes, as well as cartilage in a osteoarthritic rat model, in part via the NF-κB signaling pathway. PMID:25892273

  8. An ultrasound biomicroscopic and water jet ultrasound indentation method for detecting the degenerative changes of articular cartilage in a rabbit model of progressive osteoarthritis.

    Science.gov (United States)

    Wang, Yuexiang; Huang, Yan-Ping; Liu, Aijun; Wan, Wenbo; Zheng, Yong-Ping

    2014-06-01

    It is important to assess the early degeneration of articular cartilage associated with osteoarthritis (OA) for early intervention and treatment planning. Previously, we have developed a high frequency ultrasound and water jet indentation method for the morphologic, acoustic and mechanical assessment of articular cartilage, using the enzymatic digestion as a model of osteoarthritic degeneration. No naturally degenerated articular cartilage has been tested with the developed method. In this study, we aimed to determine the usefulness of the developed method for detecting the natural degeneration of articular cartilage in a standard surgical model of OA in rabbits. Forty adult New Zealand white female rabbits were used in this study, which included 30 experimental rabbits undergoing the right anterior cruciate ligament transection surgery and 10 control rabbits. At the 3rd, 6th, and 9th week post-surgery, 10 experimental rabbits were sacrificed, respectively, for assessment of the knee cartilage quality. The cartilage at the medial and lateral femoral condyles and tibial plateaus (four points) was measured by the high frequency ultrasound biomicroscopy, the water jet ultrasound indentation and a contact mechanical indentation test before a histopathologic analysis for grading of degeneration severity. Measured parameters were compared among different groups classified either by post-surgery time or by histopathologic grade. The results showed a general trend of increase for ultrasound roughness index and a general trend of decrease for integrated reflection coefficient, stiffness coefficient from water-jet indentation and Young's modulus (E) from the mechanical indentation with the increase of post-surgery time. Comparisons among groups with different histopathologic grades showed similar trend with the increase of degeneration severity. The water jet ultrasound indentation method was demonstrated to be an effective method to measure the mechanical properties of the

  9. Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair: International Cartilage Repair Society Recommendations Based on Current Scientific Evidence and Standards of Clinical Care

    OpenAIRE

    Mithoefer, Kai; Saris, Daniel B.F.; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J.; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats

    2011-01-01

    Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for t...

  10. 碱性成纤维细胞生长因子转染兔关节软骨细胞的研究%Transfection of basic fibroblast growth factor in rabbits' articular chondrocytes

    Institute of Scientific and Technical Information of China (English)

    曾庆彩; 鲍丽娟; 龙源深; 杨炎馨; 董文其; 李明

    2004-01-01

    背景:软骨细胞体外培养困难和表型难以维持是软骨组织工程研究的一大难题.目的:探讨碱性成纤维细胞生长因子(basic Fibroblast Growth Factor,bFGF)基因转染兔关节软骨细胞后对培养的关节软骨细胞形态、分裂增殖及代谢等方面的影响.设计:完全随机对照实验研究.地点和方法:实验在解放军第一军医大学热带军队卫生学系完成,对象为兔软骨细胞(3周龄新西兰新生兔购于第一军医大学实验动物中心).干预:将bFGF基因克隆于真核表达载体pHβ0AP-1中,构建重组真核表达载体pHβ-bFGF,转染兔关节软骨细胞.G418筛选阳性克隆,检测阳性细胞bFGF基因的表达水平.测定培养软骨细胞的DNA含量、糖醛酸含量、软骨细胞增殖情况及进行细胞周期分析.主要观察指标:DNA含量、糖醛酸含量、软骨细胞增殖情况及细胞周期分析.结果:bFGF基因转染软骨细胞表型未见显著变化;bFGF基因转染组、载体对照组、空白对照组DNA含量分别为(77.37±6 21),(40.39±4.33),(33.77±4.25)μg/瓶(P<0.01),糖醛酸含量分别为(308.8±10.2),(77.9±8.7),(80.2±10.5)μg/瓶(P<0.01),软骨细胞G1期分别为59.3±2.1,69.5±4.0,73.1±3.9(P<0.05).结论:bFGF转染关节软骨细胞后,可显著促进细胞分裂增殖并缩短细胞周期,为软骨组织工程研究提供新的技术路线及理论基础.%BACKGROUND: The difficulties in the culture in vitro of chondrocytes and in the maintenance of phenotype are big problems in the research of cartilage engineering.OBJECTIVE: To discuss the impact of basic fibroblast growth factor(bFGF)gene on the morphology, division, proliferation and metabolism of chondrocytes in culture after the transfection in articular chondrocytes of rabbits.DESIGN: A complete randomized controlled study was conducted.SETTING and PARTICIPANTS: The study was completed in the Department of Military Tropical Medicine and Hygiene, First Military Medical

  11. Comparative digital cartilage histology for human and common osteoarthritis models

    OpenAIRE

    Pedersen DR; Goetz JE; Kurriger GL; Martin JA

    2013-01-01

    Douglas R Pedersen, Jessica E Goetz, Gail L Kurriger, James A MartinDepartment of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA, USAPurpose: This study addresses the species-specific and site-specific details of weight-bearing articular cartilage zone depths and chondrocyte distributions among humans and common osteoarthritis (OA) animal models using contemporary digital imaging tools. Histological analysis is the gold-standard research tool for evaluating cartilage healt...

  12. Pathology of the calcified zone of articular cartilage in post-traumatic osteoarthritis in rat knees.

    Directory of Open Access Journals (Sweden)

    Melissa Schultz

    Full Text Available This study aimed to investigate the pathology occurring at the calcified zone of articular cartilage (CZC in the joints afflicted with post-traumatic osteoarthritis (PTOA.Rats underwent bilateral anterior cruciate ligament (ACL transection and medial meniscectomy to induce PTOA. Sham surgery was performed on another five rats to serve as controls. The rats were euthanized after four weeks of surgery and tibial plateaus were dissected for histology. The pathology of PTOA, CZC area and the tidemark roughness at six pre-defined locations on the tibial plateaus were quantified by histomorphometry.PTOA developed in the knees, generally more severe at the medial plateau than the lateral plateau, of rats in the experimental group. The CZC area was unchanged in the PTOA joints, but the topographic variations of CZC areas that presented in the control knees were reduced in the PTOA joints. The tidemark roughness decreased in areas of the medial plateau of PTOA joints and that was inversely correlated with the Mankin's score of PTOA pathology.Reduced tidemark roughness and unchanged CZC area differentiate PTOA from primary osteoarthritis, which is generally believed to have the opposite pathology at CZC, and may contribute to the distinct disease progression of the two entities of arthropathy.

  13. Intra-articular delivery of kartogenin-conjugated chitosan nano/microparticles for cartilage regeneration.

    Science.gov (United States)

    Kang, Mi Lan; Ko, Ji-Yun; Kim, Ji Eun; Im, Gun-Il

    2014-12-01

    We developed an intra-articular (IA) drug delivery system to treat osteoarthritis (OA) that consisted of kartogenin conjugated chitosan (CHI-KGN). Kartogenin, which promotes the selective differentiation of mesenchymal stem cells (MSCs) into chondrocytes, was conjugated with low-molecular-weight chitosan (LMWCS) and medium-molecular-weight chitosan (MMWCS) by covalent coupling of kartogenin to each chitosan using an ethyl(dimethylaminopropyl) carbodiimide (EDC)/N-hydroxysuccinimide (NHS) catalyst. Nanoparticles (NPs, 150 ± 39 nm) or microparticles (MPs, 1.8 ± 0.54 μm) were fabricated from kartogenin conjugated-LMWCS and -MMWCS, respectively, by an ionic gelation using tripolyphosphate (TPP). The in vitro release profiles of kartogenin from the particles showed sustained release for 7 weeks. When the effects of the CHI-KGN NPs or CHI-KGN MPs were evaluated on the in vitro chondrogenic differentiation of human bone marrow MSCs (hBMMSCs), the CHI-KGN NPs and CHI-KGN MPs induced higher expression of chondrogenic markers from cultured hBMMSCs than unconjugated kartogenin. In particular, hBMMSCs treated with CHI-KGN NPs exhibited more distinct chondrogenic properties in the long-term pellet cultures than those treated with CHI-KGN MPs. The in vivo therapeutic effects of CHI-KGN NPs or CHI-KGN MPs were investigated using a surgically-induced OA model in rats. The CHI-KGN MPs showed longer retention time in the knee joint than the CHI-KGN NPs after IA injection in OA rats. The rats treated with CHI-KGN NPs or CHI-KGN MPs by IA injection showed much less degenerative changes than untreated control or rats treated with unconjugated kartogenin. In conclusion, CHI-KGN NPs or CHI-KGN MPs can be useful polymer-drug conjugates as an IA drug delivery system to treat OA. PMID:25241157

  14. Lubricin reduces cartilage--cartilage integration.

    Science.gov (United States)

    Schaefer, Dirk B; Wendt, David; Moretti, Matteo; Jakob, Marcel; Jay, Gregory D; Heberer, Michael; Martin, Ivan

    2004-01-01

    Cartilage integration in vivo does not occur, such that even cartilage fissures do not heal. This could be due not only to the limited access of chondrocytes to the wound, but also to exogenous factors. In this paper, we tested the hypothesis that lubricin, a lubricating protein physiologically present in the synovial fluid, reduces the integrative cartilage repair capacity. Disk/ring composites of bovine articular cartilage were prepared using concentric circular blades and cultured for 6 weeks with or without treatment with 250 microg/ml lubricin applied three times per week. Following culture, the percentage of contact area between the disks and the rings, as assessed by light microscopy, were equal in both groups. The adhesive strength of the integration interface, as assessed by push-out mechanical tests, was markedly and significantly lower in lubricin-treated specimens (2.5 kPa) than in the controls (28.7 kPa). Histological observation of Safranin-O stained cross-sections confirmed the reduced integration in the lubricin treated composites. Our findings suggest that the synovial milieu, by providing lubrication of cartilage surfaces, impairs cartilage--cartilage integration. PMID:15299281

  15. Spontaneous Minced Cartilage Procedure for Unexpectedly Large Femoral Condyle Surface Defect.

    Science.gov (United States)

    Salzmann, G M; Baumann, G A; Preiss, S

    2016-01-01

    Articular cartilage defects at the knee joint are being identified and treated with increasing frequency. Chondrocytes may have strongest potential to generate high-quality repair tissue within the defective region, in particular when large diameter defects are present. Autologous chondrocyte implantation is not available in every country. We present a case where we spontaneously covered an acute cartilage defect, which was significantly larger than expected and loose during initial arthroscopic inspection after reading preoperative MRI, by mincing the separated fragment and directly implanting the autologous cartilage chips into the defective region. PMID:27504207

  16. Glycoconjugate expression of chondrocytes and perichondrium during hyaline cartilage development in the rat.

    OpenAIRE

    Zschäbitz, A; Krahn, V; Gabius, H J; Weiser, H; Khaw, A; Biesalski, H. K.; Stofft, E

    1995-01-01

    Alterations in the expression of glycoconjugate structures during cartilage development in the chondrocranium, nasal skeleton, Meckel's cartilage, limb buds, vertebral bodies and ribs were investigated comparatively in 13 to 21-d-old rat embryos. The binding patterns of 24 biotinylated lectins were analysed in serial sections and compared with results obtained using histochemical methods. Proteoglycan distribution, assessed by conventional staining procedures, was not associated with lectin b...

  17. EFFECTS OF AGE ON VISCOELASTICITY AND DEFORMATION RECOVERY OF ARTICULAR CHONDROCYTES%软骨细胞黏弹性及恢复变形与年龄相关性研究

    Institute of Scientific and Technical Information of China (English)

    张全有; 陈维毅; 卫小春; 李春江; 刘琳琳

    2009-01-01

    The aim of this study was to characterize the age-related changes of viscoelastic properties and deformation recovery of rabbit chondrocytes in natural development of articular cartilage. The micropipette aspiration combined with a standard linear viscoelastic solid model was used to quantify all parameters of chondrocytes from different age groups. Results indicate that the viscoelastic properties of chondrocytes in old group exhibited a significantly lower instantaneous modulus (E_0), equilibrium modulus (E_∞), and apparent viscosity (μ) compared with those of young group (p 0.1). The process of creep and deformation recovery of chondrocytes has changed significantly during natural development. The time t_E that old chondrocytes need to reach equilibrium is significantly less than young and adult ones (p 0.05). At the same time, maximal creep displacement L_M in old group dramatically higher than young and adult group (p 0.05). Comparisons of the deformation recovery ratio of different age groups before 8 seconds have shown that the ratio value of young group is significantly higher than those of adult and old ones (p 0.05). Additionally, there were no significant correlation between the viscoelastic parameters and the ratio of the cell to micropipette diameter. These results may be helpful for chondrocyte-based cartilage tissue engineering.%本文旨在表征年龄对软骨细胞在自然生长过程中的黏弹性和恢复变形能力的影响.结果表明:年龄对软骨细胞黏弹性及其恢复变形能力产生显著影响,老年组软骨细胞各项黏弹性参数值均明显高于幼年和中年组软骨细胞(p0.05);老年组软骨细胞蠕变达到平衡态所需时间t_E显著小于幼年和中年组(p0.05).老年组软骨细胞最大蠕变位移L_M显著大于幼年和中年组(p0.05).老年组软骨细胞恢复变形时间t_R显著大于幼年和中年组(p0.05).恢复变形前8s的分析发现,幼年组软骨细胞恢复变形率K_y显

  18. The effect of a slightly acidic somatomedin peptide (ILAs) on the sulphation of proteoglycans from articular and growth plate chondrocytes in culture

    International Nuclear Information System (INIS)

    Chondrocyte cultures were prepared from rabbit growth plate (GPC) and articular (ARC) chondrocytes. These two cell types have distinct morphological characteristics. The cells reached maximum numbers by days 10 and 21 for ARC and GPC, respectively. The proteoglycans (PG) contained in the cellular pool were extracted and purified by DEAE cellulose chromatography. The effect of a partially purified somatomedin peptide with insulin-like activity on [35S]sulphate incorporation into PG was evaluated. In both ARC and GPC a significant stimulation of [35S]sulphate uptake into PG subunits was obtained with 1 ng Eq./ml of somatomedin peptide. In order to obtain the same stimulatory effect with porcine insulin, a 1000-fold greater concentration was required. The electrophoretic patterns of the PG subunits on acrylamide-agarose electrophoresis were identical on control incubations and after stimulation with the somatomedin peptide. These data demonstrate in vitro biological activity of this peptide on well differentiated articular and epiphyseal growth plate chondrocytes in culture. These cultures appear to provide a sensitive biological assay for somatomedin peptides. (author)

  19. Chondrocyte outgrowth into a gelatin scaffold in a single impact load model of damage/repair – effect of BMP-2

    Directory of Open Access Journals (Sweden)

    Vincent Thea

    2007-12-01

    Full Text Available Abstract Background Articular cartilage has little capacity for repair in vivo, however, a small number of studies have shown that, in vitro, a damage/repair response can be induced. Recent work by our group has shown that cartilage can respond to single impact load and culture by producing repair cells on the articular surface. The purpose of this study was to identify whether chondrocyte outgrowth into a 3D scaffold could be observed following single impact load and culture. The effect of bone morphogenic-2 (BMP-2 on this process was investigated. Methods Cartilage explants were single impact loaded, placed within a scaffold and cultured for up to 20 days +/- BMP-2. Cell numbers in the scaffold, on and extruding from the articular surface were quantified and the immunohistochemistry used to identify the cellular phenotype. Results Following single impact load and culture, chondrocytes were observed in a 3D gelatin scaffold under all culture conditions. Chondrocytes were also observed on the articular surface of the cartilage and extruding out of the parent cartilage and on to the cartilage surface. BMP-2 was demonstrated to quantitatively inhibit these events. Conclusion These studies demonstrate that articular chondrocytes can be stimulated to migrate out of parent cartilage following single impact load and culture. The addition of BMP-2 to the culture medium quantitatively reduced the repair response. It may be that the inhibitory effect of BMP-2 in this experimental model provides a clue to the apparent inability of articular cartilage to heal itself following damage in vivo.

  20. The effect of supplementation of a glutamine precursor on the growth plate, articular cartilage and cancellous bone in fundectomy-induced osteopenic bone.

    Science.gov (United States)

    Tomaszewska, Ewa; Dobrowolski, Piotr; Prost, Łukasz; Hułas-Stasiak, Monika; Muszyński, Siemowit; Blicharski, Tomasz

    2016-05-01

    The aim of the study was to investigate the effect of 2-oxoglutaric acid (2-Ox) supplementation (a precursor of glutamine and hydroxyproline, the most abundant amino acid of collagen) on cartilage and bone in pigs after fundectomy. Pigs at the age of forty days were subjected to fundectomy and divided into two groups depending on 2-Ox supplementation (at the daily dosage of 0.4 g/kg of body weight). Other pigs were sham operated. Pigs were euthanized at the age of eight months. An analysis of the morphometry of trabeculae, growth plate and articular cartilage in fundectomy-induced osteopenic bone was performed. Moreover, the levels of expression of osteocalcin, osteopontin and osteoprotegerin in trabecular bone and osteocalcin in articular cartilage were evaluated. Articular cartilage was thinnest in fundectomized pigs and thickest in 2-Ox-supplemented animals after fundectomy. Moreover, 2-Ox supplementation after fundectomy enhanced the total thickness of the growth plate and trabeculae in fundectomized pigs. The most evident signal for osteocalcin and osteoprotegerin in trabecular bone was in sham-operated and 2-Ox-supplemented pigs; a low reaction was observed in the fundectomized group. Additionally, as a long-term postoperative consequence, a change was observed in the expression of osteocalcin in articular cartilage. It seems that 2-Ox is suitable for use in preventing the negative effects of fundectomy on cancellous bone and cartilage. PMID:26725871

  1. The DNA Repair Enzyme Apurinic/Apyrimidinic Endonuclease (Apex Nuclease 2 Has the Potential to Protect against Down-Regulation of Chondrocyte Activity in Osteoarthritis

    Directory of Open Access Journals (Sweden)

    Naoko Yui

    2014-08-01

    Full Text Available Apurinic/apyrimidinic endonuclease 2 (Apex 2 plays a critical role in DNA repair caused by oxidative damage in a variety of human somatic cells. We speculated that chondrocyte Apex 2 may protect against the catabolic process of articular cartilage in osteoarthritis (OA. Higher levels of Apex 2 expression were histologically observed in severely compared with mildly degenerated OA cartilage from STR/OrtCrlj mice, an experimental model which spontaneously develops OA. The immunopositivity of Apex 2 was significantly correlated with the degree of cartilage degeneration. Moreover, the OA-related catabolic factor interleukin-1β induced the expression of Apex 2 in chondrocytes, while Apex 2 silencing using small interfering RNA reduced chondrocyte activity in vitro. The expression of Apex 2 in chondrocytes therefore appears to be associated with the degeneration of articular cartilage and could be induced by an OA-related catabolic factor to protect against the catabolic process of articular cartilage. Our findings suggest that Apex 2 may have the potential to prevent the catabolic stress-mediated down-regulation of chondrocyte activity in OA.

  2. μ-XRF and μ-XANES at calcification fronts of human articular cartilage

    International Nuclear Information System (INIS)

    Full text: One of the main threats to human health from heavy metals is associated with exposure to lead (Pb), which is associated with chronic diseases in the nervous, hematopoietic, skeletal, renal and endocrine system. Although much progress has been made to limit Pb exposure in industrialized countries, primarily through the elimination of leaded gasoline, workplace exposures and leaded pipes, most adults have already accumulated a substantial body burden of Pb. Most of the affiliated Pb is deposited in human bones, where it is stored up to 20 years and accounts for 90.95 of the total lead body burden. Pb is able to displace Ca2+ by cation exchange processes in the hydroxyapatite crystal (the main constituent of bone) and is liberated from it in cases of increased bone turnover such as osteoporosis, pregnancy, hyperthyroidism and hyperparathyroidism. Besides these phenomenological studies on the release of Pb from human calcified tissue analytical studies are essential to gain insight on storage sites and storage mechanisms on a microscopic scale. Therefore detailed synchrotron radiation induced micro x-ray fluorescence analyses (SR μ - XRF) have been carried out to study the distribution of Pb in bones from human joints (femoral heads and patellas). As a very recent result we found a highly specific accumulation of Pb in the tidemark, which is a metabolically active mineralization front (thickness about 5 - 10 μm) between calcified and non-calcified articular cartilage and plays an important role in developing osteoarthritis. From the results obtained for single tidemark bones one would expect an accumulation of Pb in both tidemarks of bones showing tidemark duplication. However, Pb shows a strong accumulation at the older of the two tidemarks, while it is not present at the younger one. A comparison of the Pb distribution with the one of other tidemark-seekers (e.g. Zn) exhibits a time difference in the accumulation of different metals at the calcification

  3. Autologous bone marrow concentrate: review and application of a novel intra-articular orthobiologic for cartilage disease.

    Science.gov (United States)

    Sampson, Steven; Botto-van Bemden, Angie; Aufiero, Danielle

    2013-09-01

    Younger adults, aged 65 years; however, the limited long-term durability of implanted prostheses decreases the preference of using such methods in more active patients aged cell-based orthobiologic injection therapies (pertaining to therapeutic injectables that aim to restore the biologic environment and/or structural components of diseased or damaged musculoskeletal tissue) is of tremendous interest for younger, more active patients, and is even more appealing in that such therapy can be delivered at point-of-care in the clinic during an office visit. Notably, the exponential rate of progress in biotechnology has allowed for immediate application of myriad novel therapies prior to clear evidence of benefit from randomized clinical trials. Orthobiologic intra-articular injection therapies include HA and platelet-rich plasma (PRP). We report on current, available findings for a third-generation intra-articular orthobiologic injectable therapy for cartilage disease, bone marrow concentrate (BMC). Bone marrow concentrate contains mesenchymal stem cells (MSCs), hematopoetic stem cells, platelets (containing growth factors), and cytokines. The anti-inflammatory and immunomodulatory properties of bone marrow stem cells (BMSCs) can facilitate regeneration of tissue. Additionally, BMSCs enhance the quality of cartilage repair by increasing aggrecan content and tissue firmness. Following bone marrow aspiration (BMA), BMC is easily prepared using centrifugation, and is available for a same-day procedure with minimal manipulation of cells, thus complying with US Food and Drug Association (FDA) restrictions. To date, there are no published randomized controlled trials on the efficacy of use of autologous BMC intra-articular injections performed as a same-day in-office procedure for treating patients with cartilage disease; however, several publications have reported the ease of use of this method, its strong safety profile, and the fundamental science suggesting great

  4. Intra-articular injection of synovium-derived mesenchymal stem cells and hyaluronic acid promote regeneration of massive cartilage defects in rabbits

    Directory of Open Access Journals (Sweden)

    Vyacheslav Ogay

    2014-01-01

    Full Text Available Introduction: The purpose of this study was to investigate whether intra-articular injection of synovium-derived mesenchymal stem cells (SD MSCs with low molecular weight hyaluronic acid (HA could promote regeneration of massive cartilage in rabbits. Material and methods: The SD MSCs were harvested from the knees of 10 Flemish giant rabbits, expanded in culture, and characterized. A reproducible 4-mm cylindrical defect was created in the intercondylar groove area using a kit for the mosaic chondroplasty of femoral condyle COR (De Puy, Mitek. The defect was made within the cartilage layer without destruction of subchondral bone. Two weeks after the cartilage defect, SD MSCs (2 × 106 cell/0.15 ml were suspended in 0.5% low molecular weight HA (0.15 ml and injected into the left knee, and HA solution (0.30 ml alone was placed into the right knee. Cartilage regeneration in the experimental and control groups were evaluated by macroscopically and histologically at 10, 30, and 60 days. Results: On day 10, after intra-articular injection of SD MSCs, we observed an early process of cartilage regeneration in the defect area. Histological studies revealed that cartilage defect was covered by a thin layer of spindle-shaped undifferentiated cells and proliferated chodroblasts. In contrast, an injection of HA did not induce reparation of cartilage in the defect area. At 30 days, macroscopic observation showed that the size of cartilage defect after SD MSC injection was significantly smaller than after HA injection. Histological score was also better in the MSC- treated intercondylar defect. At 60 days after MSC treatment, cartilage defect was nearly nonexistent and looked similar to an intact cartilage. Conclusion: Thus, intra-articular injection of SD MSCs can adhere to the defect in the intercondylar area, and promote cartilage regeneration in rabbits.

  5. Evaluation of grades 3 and 4 chondromalacia of the knee using T2*-weighted 3D gradient-echo articular cartilage imaging

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, B.J. [Dept. of Radiology, Univ. of Miami School of Medicine, FL (United States)

    2001-06-01

    Objective. To determine the accuracy of T2*-weighted three-dimensional (3D) gradient-echo articular cartilage imaging in the identification of grades 3 and 4 chondromalacia of the knee.Design and patients. A retrospective evaluation of 80 patients who underwent both arthroscopic and MRI evaluation was performed. The 3D images were interpreted by one observer without knowledge of the surgical results. The medial and lateral femoral condyles, the medial and lateral tibial plateau, the patellar cartilage and trochlear groove were evaluated. MR cartilage images were considered positive if focal reduction of cartilage thickness was present (grade 3 chondromalacia) or if complete loss of cartilage was present (grade 4 chondromalacia). Comparison of the 3D MR results with the arthroscopic findings was performed.Results. Eighty patients were included in the study group. A total of 480 articular cartilage sites were evaluated with MRI and arthroscopy. Results of MR identification of grades 3 and 4 chondromalacia, all sites combined, were: sensitivity 83%, specificity 97%, false negative rate 17%, false positive rate 3%, positive predictive value 87%, negative predictive value 95%, overall accuracy 93%.Conclusion. The results demonstrate that T2*-weighted 3D gradient-echo articular cartilage imaging can identify grades 3 and 4 chondromalacia of the knee. (orig.)

  6. Dependence of light attenuation and backscattering on collagen concentration and chondrocyte density in agarose scaffolds

    International Nuclear Information System (INIS)

    Optical coherence tomography (OCT) has been applied for high resolution imaging of articular cartilage. However, the contribution of individual structural elements of cartilage on OCT signal has not been thoroughly studied. We hypothesize that both collagen and chondrocytes, essential structural components of cartilage, act as important light scatterers and that variation in their concentrations can be detected by OCT through changes in backscattering and attenuation. To evaluate this hypothesis, we established a controlled model system using agarose scaffolds embedded with variable collagen concentrations and chondrocyte densities. Using OCT, we measured the backscattering coefficient (µb) and total attenuation coefficient (µt) in these scaffolds. Along our hypothesis, light backscattering and attenuation in agarose were dependent on collagen concentration and chondrocyte density. Significant correlations were found between µt and chondrocyte density (ρ = 0.853, p < 0.001) and between µt and collagen concentration (ρ = 0.694, p < 0.001). µb correlated significantly with chondrocyte density (ρ = 0.504, p < 0.001) but not with collagen concentration (ρ = 0.103, p = 0.422) of the scaffold. Thus, quantitation of light backscattering and, especially, attenuation could be valuable when evaluating the integrity of soft tissues, such as articular cartilage with OCT. (paper)

  7. Articular cartilage-derived cells hold a strong osteogenic differentiation potential in comparison to mesenchymal stem cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Salamon, Achim, E-mail: achim.salamon@med.uni-rostock.de [Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany); Jonitz-Heincke, Anika, E-mail: anika.jonitz@med.uni-rostock.de [Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medical Center, Doberaner Straße 142, D-18057 Rostock (Germany); Adam, Stefanie, E-mail: stefanie.adam@med.uni-rostock.de [Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany); Rychly, Joachim, E-mail: joachim.rychly@med.uni-rostock.de [Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany); Müller-Hilke, Brigitte, E-mail: brigitte.mueller-hilke@med.uni-rostock.de [Institute of Immunology, Rostock University Medical Center, Schillingallee 68, D-18057 Rostock (Germany); Bader, Rainer, E-mail: rainer.bader@med.uni-rostock.de [Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medical Center, Doberaner Straße 142, D-18057 Rostock (Germany); Lochner, Katrin, E-mail: katrin.lochner@med.uni-rostock.de [Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medical Center, Doberaner Straße 142, D-18057 Rostock (Germany); Peters, Kirsten, E-mail: kirsten.peters@med.uni-rostock.de [Department of Cell Biology, Rostock University Medical Center, Schillingallee 69, D-18057 Rostock (Germany)

    2013-11-01

    Cartilaginous matrix-degenerative diseases like osteoarthritis (OA) are characterized by gradual cartilage erosion, and also by increased presence of cells with mesenchymal stem cell (MSC) character within the affected tissues. Moreover, primary chondrocytes long since are known to de-differentiate in vitro and to be chondrogenically re-differentiable. Since both findings appear to conflict with each other, we quantitatively assessed the mesenchymal differentiation potential of OA patient cartilage-derived cells (CDC) towards the osteogenic and adipogenic lineage in vitro and compared it to that of MSC isolated from adipose tissue (adMSC) of healthy donors. We analyzed expression of MSC markers CD29, CD44, CD105, and CD166, and, following osteogenic and adipogenic induction in vitro, quantified their expression of osteogenic and adipogenic differentiation markers. Furthermore, CDC phenotype and proliferation were monitored. We found that CDC exhibit an MSC CD marker expression pattern similar to adMSC and a similar increase in proliferation rate during osteogenic differentiation. In contrast, the marked reduction of proliferation observed during adipogenic differentiation of adMSC was absent in CDC. Quantification of differentiation markers revealed a strong osteogenic differentiation potential for CDC, however almost no capacity for adipogenic differentiation. Since in the pathogenesis of OA, cartilage degeneration coincides with high bone turnover rates, the high osteogenic differentiation potential of OA patient-derived CDC may affect clinical therapeutic regimens aiming at autologous cartilage regeneration in these patients. - Highlights: • We analyze the mesenchymal differentiation capacity of cartilage-derived cells (CDC). • CDC express mesenchymal stem cell (MSC) markers CD29, CD44, CD105, and CD166. • CDC and MSC proliferation is reduced in adipogenesis and increased in osteogenesis. • Adipogenic differentiation is virtually absent in CDC, but

  8. Articular cartilage-derived cells hold a strong osteogenic differentiation potential in comparison to mesenchymal stem cells in vitro

    International Nuclear Information System (INIS)

    Cartilaginous matrix-degenerative diseases like osteoarthritis (OA) are characterized by gradual cartilage erosion, and also by increased presence of cells with mesenchymal stem cell (MSC) character within the affected tissues. Moreover, primary chondrocytes long since are known to de-differentiate in vitro and to be chondrogenically re-differentiable. Since both findings appear to conflict with each other, we quantitatively assessed the mesenchymal differentiation potential of OA patient cartilage-derived cells (CDC) towards the osteogenic and adipogenic lineage in vitro and compared it to that of MSC isolated from adipose tissue (adMSC) of healthy donors. We analyzed expression of MSC markers CD29, CD44, CD105, and CD166, and, following osteogenic and adipogenic induction in vitro, quantified their expression of osteogenic and adipogenic differentiation markers. Furthermore, CDC phenotype and proliferation were monitored. We found that CDC exhibit an MSC CD marker expression pattern similar to adMSC and a similar increase in proliferation rate during osteogenic differentiation. In contrast, the marked reduction of proliferation observed during adipogenic differentiation of adMSC was absent in CDC. Quantification of differentiation markers revealed a strong osteogenic differentiation potential for CDC, however almost no capacity for adipogenic differentiation. Since in the pathogenesis of OA, cartilage degeneration coincides with high bone turnover rates, the high osteogenic differentiation potential of OA patient-derived CDC may affect clinical therapeutic regimens aiming at autologous cartilage regeneration in these patients. - Highlights: • We analyze the mesenchymal differentiation capacity of cartilage-derived cells (CDC). • CDC express mesenchymal stem cell (MSC) markers CD29, CD44, CD105, and CD166. • CDC and MSC proliferation is reduced in adipogenesis and increased in osteogenesis. • Adipogenic differentiation is virtually absent in CDC, but

  9. Gene Transfer Strategies to Promote Chondrogenesis and Cartilage Regeneration.

    Science.gov (United States)

    Im, Gun-Il

    2016-04-01

    Gene transfer has been used experimentally to promote chondrogenesis and cartilage regeneration. While it is controversial to apply gene therapy for nonlethal conditions such as cartilage defect, there is a possibility that the transfer of therapeutic transgenes may dramatically increase the effectiveness of cell therapy and reduce the quantity of cells that are needed to regenerate cartilage. Single or combination of growth factors and transcription factors has been transferred to mesenchymal stem cells or articular chondrocytes using both nonviral and viral approaches. The current challenge for the clinical applications of genetically modified cells is ensuring the safety of gene therapy while guaranteeing effectiveness. Viral gene delivery methods have been mainstays currently with enhanced safety features being recently refined. On the other hand, efficiency has been greatly improved in nonviral delivery. This review summarizes the history and recent update on the gene transfer to enhance chondrogenesis from stem cells or articular chondrocytes. PMID:26414246

  10. Variations in radiographic appearance of articular cartilage of knee joints in persons of 35 to 65 years of age

    Directory of Open Access Journals (Sweden)

    Himani Pulivarthi

    2015-01-01

    Full Text Available Background: Osteoarthritis is a slowly progressive degenerative disease characterized by gradual loss of articular cartilage. Osteoarthritis is not a normal process of ageing processes. Age related changes are distinct from osteoarthritic changes but when coupled with certain precipitating factors like obesity, muscle weakness and neurological dysfunction may play an important role in the causation of osteoarthritis. Osteoarthritis occurrence appears to increase with patient's age in a non-linear fashion. The prevalence of disease increases dramatically after the age of 50 years, likely because of age related alterations in collagen and proteoglycan synthesis coupled with diminished nutrient supply to the cartilage. Methods: In this paper presenting the naked eye assessment of radiographic appearance of articular cartilage of knee joints of 100 persons (both men and women of 35 to 65 years of age with symptoms like pain and stiffness of the joint. Results: Parameters like changes in the joint space width, the presence or absence of osteophytes and subchondral sclerosis and cysts were noted. The correlation between the patient's age, sex, symptoms and radiological appearance were observed. Conclusion: Osteoarthritis has a higher prevalence and more often generalized in women than in men. Before the age of 50 years, the incidence of osteoarthritis is low and men have a slightly higher prevalence than women, but after the age of 50 years, the disease becomes more frequent and women have a much higher prevalence with a female to male ration of about 12:1. The reason for this is sex difference in cartilage volume. [Int J Res Med Sci 2015; 3(1.000: 22-26

  11. The significance of electromechanical and osmotic forces in the nonequilibrium swelling behavior of articular cartilage in tension.

    Science.gov (United States)

    Grodzinsky, A J; Roth, V; Myers, E; Grossman, W D; Mow, V C

    1981-11-01

    Studies were conducted of some of the nonequilibrium, electrolyte-activated, electromechanical and osmotic processes that can affect the tensile properties of articular cartilage. We measured changes in tensile force that were induced by altering the ionic environment of strips of cartilage held at fixed length. We compared the kinetics of changes in these macroscopically measured isometric tensile forces to theoretical estimates of the time constants that characterize the underlying physical and chemical mechanisms occurring within the cartilage specimens during the experiment. Changes in the tensile force induced by changing the bath neutral salt concentration surrounding the specimen appear to be rate-limited by the diffusion of the salt into the specimen. That is, the mechanical stress relaxation process resulting from changes in salt concentration seems to be occurring at least as rapidly as the diffusion of salt into the matrix. When the bath concentration of CaCl2 or HCl is varied, the rate of change in the resulting isometric stresses indicates that Ca++ and H+ ions are binding to the cartilage matrix macromolecules. PMID:7311487

  12. Transforming growth factor-beta 1 stimulates synthesis of proteoglycan aggregates in calf articular cartilage organ cultures

    Energy Technology Data Exchange (ETDEWEB)

    Morales, T.I. (Bone Research Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, MD (United States))

    1991-04-01

    Previous work showed that transforming growth factor-beta 1 (TGF-beta 1), added alone to bovine cartilage organ cultures, stimulated (35S)sulfate incorporation into macromolecular material but did not investigate the fidelity of the stimulated system to maintain synthesis of cartilage-type proteoglycans. This paper provides evidence that chondrocytes synthesize the appropriate proteoglycan matrix under TGF-beta 1 stimulation: (1) there is a coordinated increase in hyaluronic acid and proteoglycan monomer synthesis, (2) link-stable proteoglycan aggregates are assembled, (3) the hybrid chondroitin sulfate/keratan sulfate monomeric species is synthesized, and (4) there is an increase in protein core synthesis. Some variation in glycosylation patterns was observed when proteoglycans synthesized under TGF-beta 1 stimulation were compared to those synthesized under basal conditions. Thus comparing TGF-beta 1 to basal samples respectively, the monomers were larger (Kav on Sepharose CL-2B = 0.29 vs 0.41), the chondroitin sulfate chains were longer by approximately 3.5 kDa, the percentage of total glycosaminoglycan in keratan sulfate increased slightly from approximately 4% (basal) to approximately 6%, and the unsulfated disaccharide decreased from 28% (basal) to 12%. All of these variations are in the direction of a more anionic proteoglycan. Since the ability of proteoglycans to confer resiliency to the cartilage matrix is directly related to their anionic nature, these changes would presumably have a beneficial effect on tissue function.

  13. Integration of Stem Cell to Chondrocyte-Derived Cartilage Matrix in Healthy and Osteoarthritic States in the Presence of Hydroxyapatite Nanoparticles.

    Science.gov (United States)

    Dua, Rupak; Comella, Kristin; Butler, Ryan; Castellanos, Glenda; Brazille, Bryn; Claude, Andrew; Agarwal, Arvind; Liao, Jun; Ramaswamy, Sharan

    2016-01-01

    We investigated the effectiveness of integrating tissue engineered cartilage derived from human bone marrow derived stem cells (HBMSCs) to healthy as well as osteoarthritic cartilage mimics using hydroxyapatite (HA) nanoparticles immersed within a hydrogel substrate. Healthy and diseased engineered cartilage from human chondrocytes (cultured in agar gels) were integrated with human bone marrow stem cell (HBMSC)-derived cartilaginous engineered matrix with and without HA, and evaluated after 28 days of growth. HBMSCs were seeded within photopolymerizable poly (ethylene glycol) diacrylate (PEGDA) hydrogels. In addition, we also conducted a preliminary in vivo evaluation of cartilage repair in rabbit knee chondral defects treated with subchondral bone microfracture and cell-free PEGDA with and without HA. Under in vitro conditions, the interfacial shear strength between tissue engineered cartilage derived from HBMSCs and osteoarthritic chondrocytes was significantly higher (p < 0.05) when HA nanoparticles were incorporated within the HBMSC culture system. Histological evidence confirmed a distinct spatial transition zone, rich in calcium phosphate deposits. Assessment of explanted rabbit knees by histology demonstrated that cellularity within the repair tissues that had filled the defects were of significantly higher number (p < 0.05) when HA was used. HA nanoparticles play an important role in treating chondral defects when osteoarthritis is a co-morbidity. We speculate that the calcified layer formation at the interface in the osteoarthritic environment in the presence of HA is likely to have attributed to higher interfacial strength found in vitro. From an in vivo standpoint, the presence of HA promoted cellularity in the tissues that subsequently filled the chondral defects. This higher presence of cells can be considered important in the context of accelerating long-term cartilage remodeling. We conclude that HA nanoparticles play an important role in engineered

  14. Integration of Stem Cell to Chondrocyte-Derived Cartilage Matrix in Healthy and Osteoarthritic States in the Presence of Hydroxyapatite Nanoparticles.

    Directory of Open Access Journals (Sweden)

    Rupak Dua

    Full Text Available We investigated the effectiveness of integrating tissue engineered cartilage derived from human bone marrow derived stem cells (HBMSCs to healthy as well as osteoarthritic cartilage mimics using hydroxyapatite (HA nanoparticles immersed within a hydrogel substrate. Healthy and diseased engineered cartilage from human chondrocytes (cultured in agar gels were integrated with human bone marrow stem cell (HBMSC-derived cartilaginous engineered matrix with and without HA, and evaluated after 28 days of growth. HBMSCs were seeded within photopolymerizable poly (ethylene glycol diacrylate (PEGDA hydrogels. In addition, we also conducted a preliminary in vivo evaluation of cartilage repair in rabbit knee chondral defects treated with subchondral bone microfracture and cell-free PEGDA with and without HA. Under in vitro conditions, the interfacial shear strength between tissue engineered cartilage derived from HBMSCs and osteoarthritic chondrocytes was significantly higher (p < 0.05 when HA nanoparticles were incorporated within the HBMSC culture system. Histological evidence confirmed a distinct spatial transition zone, rich in calcium phosphate deposits. Assessment of explanted rabbit knees by histology demonstrated that cellularity within the repair tissues that had filled the defects were of significantly higher number (p < 0.05 when HA was used. HA nanoparticles play an important role in treating chondral defects when osteoarthritis is a co-morbidity. We speculate that the calcified layer formation at the interface in the osteoarthritic environment in the presence of HA is likely to have attributed to higher interfacial strength found in vitro. From an in vivo standpoint, the presence of HA promoted cellularity in the tissues that subsequently filled the chondral defects. This higher presence of cells can be considered important in the context of accelerating long-term cartilage remodeling. We conclude that HA nanoparticles play an important role in

  15. Comparison of articular cartilage repair with different hydrogel-human umbilical cord blood-derived mesenchymal stem cell composites in a rat model

    OpenAIRE

    Chung, Jun Young; Song, Minjung; Ha, Chul-Won; Kim, Jin-A; Lee, Choong-Hee; Park, Yong-Beom

    2014-01-01

    Introduction The present work was designed to explore the feasibility and efficacy of articular cartilage repair using composites of human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) and four different hydrogels in a rat model. Methods Full-thickness articular cartilage defects were created at the trochlear groove of femur in both knees of rats. Composites of hUCB-MSCs and four different hydrogels (group A, 4% hyaluronic acid; group B, 3% alginate:30% pluronic (1:1, v/v); ...

  16. Type II and VI collagen in nasal and articular cartilage and the effect of IL-1 alpha on the distribution of these collagens

    OpenAIRE

    Jansen, I.D.C.; Hollander, A P; Buttle, D. J.; Everts, V.

    2010-01-01

    The distribution of type II and VI collagen was immunocytochemically investigated in bovine articular and nasal cartilage. Cartilage explants were used either fresh or cultured for up to 4 weeks with or without interleukin 1α (IL-1α). Sections of the explants were incubated with antibodies for both types of collagen. Microscopic analyses revealed that type II collagen was preferentially localized in the interchondron matrix whereas type VI collagen was primarily found in the direct vicinity o...

  17. An exploration of the ability of tepoxalin to ameliorate the degradation of articular cartilage in a canine in vitro model

    Directory of Open Access Journals (Sweden)

    Clegg Peter D

    2009-07-01

    Full Text Available Abstract Background To study the ability of tepoxalin, a dual inhibitor of cyclooxygenase (COX and lipoxygenase (LOX and its active metabolite to reduce the catabolic response of cartilage to cytokine stimulation in an in vitro model of canine osteoarthritis (OA. Grossly normal cartilage was collected post-mortem from seven dogs that had no evidence of joint disease. Cartilage explants were cultured in media containing the recombinant canine interleukin-1β (IL-1β at 100 ng/ml and recombinant human oncostatin-M (OSM at 50 ng/ml. The effects of tepoxalin and its metabolite were studied at three concentrations (1 × 10-5, 1 × 10-6 and 1 × 10-7 M. Total glycosaminoglycan (GAG and collagen (hydroxyproline release from cartilage explants were used as outcome measures of proteoglycan and collagen depletion respectively. PGE2 and LTB4 assays were performed to study the effects of the drug on COX and LOX activity. Results Treatment with IL-1β and OSM significantly upregulated both collagen (p = 0.004 and proteoglycan (p = 0.001 release from the explants. Tepoxalin at 10-5 M and 10-6 M caused a decrease in collagen release from the explants (p = 0.047 and p = 0.075. Drug treatment showed no effect on GAG release. PGE2 concentration in culture media at day 7 was significantly increased by IL-1β and OSM and treatment with both tepoxalin and its metabolite showed a trend towards dose-dependent reduction of PGE2 production. LTB4 concentrations were too low to be quantified. Cytotoxicity assays suggested that neither tepoxalin nor its metabolite had a toxic effect on the cartilage chondrocytes at the concentrations and used in this study. Conclusion This study provides evidence that tepoxalin exerts inhibition of COX and can reduce in vitro collagen loss from canine cartilage explants at a concentration of 10-5 M. We can conclude that, in this model, tepoxalin can partially inhibit the development of cartilage degeneration when it is available locally to

  18. Celastrol, an NF-κB inhibitor, ameliorates hypercalciuria and articular cartilage lesions in a mouse model of secondary osteoporosis.

    Science.gov (United States)

    Liu, Xiaodong; Cai, Feng; Zhang, Yan; Yang, Anli; Liu, Liang

    2016-04-01

    Notwithstanding compelling contribution of NF-κB to the progression of osteoporosis has been reported, little is known regarding direct inhibition of NF-κB benefiting osteoporosis. In this study, therefore, we evaluated the role of celastrol, an NF-κB inhibitor, in a mouse model of secondary osteoporosis. Animals were divided into three groups as Sham (control), SO (secondary osteoporosis) and SO + CA (secondary osteoporosis treated with celastrol). Significant decreases in body weight and body fat were observed following celastrol treatment in SO group, but leptin levels were much higher. Celastrol also exhibited a significant decrease in urinary calcium excretion. Moreover, other important events were observed after celastrol treatment, covering substantial decrements in serum concentrations of PTH, TRAP-5b, CTX and DPD, improved structure of articular cartilage and cancellous bone (revealed by H&E and safranin-O staining), and significant decline in levels of NF-κB (P65), MMP-1, and MMP-9. These findings demonstrated that celastrol treatment not only improved abnormal lipid metabolism and hypercalciuria in mice subjected to secondary osteoporosis, but also ameliorated articular cartilage lesions. Our results provided evidence of targeted therapy for NF-κB in the clinical treatment of secondary osteoporosis. PMID:26980429

  19. High Density Infill in Cracks and Protrusions from the Articular Calcified Cartilage in Osteoarthritis in Standardbred Horse Carpal Bones

    Directory of Open Access Journals (Sweden)

    Sheila Laverty

    2015-04-01

    Full Text Available We studied changes in articular calcified cartilage (ACC and subchondral bone (SCB in the third carpal bones (C3 of Standardbred racehorses with naturally-occurring repetitive loading-induced osteoarthritis (OA. Two osteochondral cores were harvested from dorsal sites from each of 15 post-mortem C3 and classified as control or as showing early or advanced OA changes from visual inspection. We re-examined X-ray micro-computed tomography (µCT image sets for the presence of high-density mineral infill (HDMI in ACC cracks and possible high-density mineralized protrusions (HDMP from the ACC mineralizing (tidemark front (MF into hyaline articular cartilage (HAC. We hypothesized and we show that 20-µm µCT resolution in 10-mm diameter samples is sufficient to detect HDMI and HDMP: these are lost upon tissue decalcification for routine paraffin wax histology owing to their predominant mineral content. The findings show that µCT is sufficient to discover HDMI and HDMP, which were seen in 2/10 controls, 6/9 early OA and 8/10 advanced OA cases. This is the first report of HDMI and HDMP in the equine carpus and in the Standardbred breed and the first to rely solely on µCT. HDMP are a candidate cause for mechanical tissue destruction in OA.

  20. An initial experimental study-the value of gadolinium-enhanced MRI and delay enhanced MRI in detecting articular cartilage degeneration of the rabbit knee

    International Nuclear Information System (INIS)

    Objective: To explore the appearance and value of early and delaye Gadolinium- enhanced MRI in detecting aricular cartilage generation of rabbit knee. Methods: Twenty adult New Zealand rabbits were randomly divided into five groups (A, B, C, D, E). Intra-articular injection of Papain was performed to establish animal models of different stages of cartilage degeneration in the right knees of A, B, C, D groups, and MR scan was conducted 24 hours,one week one month and three months after the last Papain injection. The knees were scanned bilaterally with T1WI and 3D-FS-SPGR in sagittal plane. The signal intensity ratio between articular cartilage and surrounding soft tissue was measured at plain scan and 0, 2, 4 hours after intravenous injection of gadolinium (Gd-DTPA). The articular cartilage was pathologically examined (HE and alcican blue stain). Results: In 3D-FS-SPGR sequence, it showed significant difference in the SIR between processing side of four groups (F=7.961, P1WI sequence in detecting the change of cartilage signal intensity. (2)SIR on early and delayed Gadolinium-enhanced MRI has the ability in evaluating the early stage change of cartilage degeneration. (authors)

  1. Hyaline articular cartilage dissected by papain: light and scanning electron microscopy and micromechanical studies.

    OpenAIRE

    O'Connor, P; Brereton, J D; Gardner, D.L.

    1984-01-01

    Papain was used to digest the hyaline femoral condylar cartilages of 30 adult Wistar rats. Matrix proteoglycan degradation was assessed by the light microscopy of paraffin sections stained with toluidine blue. The extent of surface structural change was estimated by scanning electron microscopy, and the structural integrity of the hyaline cartilage tested by the controlled impact of a sharp pin. The results demonstrated an early loss of cartilage metachromasia, increasing with time of papain ...

  2. Leukocyte and Platelet Rich Plasma (L-PRP) Versus Leukocyte and Platelet Rich Fibrin (L-PRF) For Articular Cartilage Repair of the Knee: A Comparative Evaluation in an Animal Model

    OpenAIRE

    Kazemi, Davoud; Fakhrjou, Ashraf

    2015-01-01

    Background: Articular cartilage injuries of the knee are among the most debilitating injuries leading to osteoarthritis due to limited regenerative capability of cartilaginous tissue. The use of platelet concentrates containing necessary growth factors for cartilage healing has recently emerged as a new treatment method. Objectives: The efficacy of two types of different platelet concentrates were compared in the treatment of acute articular cartilage injuries of the knee in an animal model. ...

  3. Altered swelling and ion fluxes in articular cartilage as a biomarker in osteoarthritis and joint immobilization: a computational analysis

    Science.gov (United States)

    Manzano, Sara; Manzano, Raquel; Doblaré, Manuel; Doweidar, Mohamed Hamdy

    2015-01-01

    In healthy cartilage, mechano-electrochemical phenomena act together to maintain tissue homeostasis. Osteoarthritis (OA) and degenerative diseases disrupt this biological equilibrium by causing structural deterioration and subsequent dysfunction of the tissue. Swelling and ion flux alteration as well as abnormal ion distribution are proposed as primary indicators of tissue degradation. In this paper, we present an extension of a previous three-dimensional computational model of the cartilage behaviour developed by the authors to simulate the contribution of the main tissue components in its behaviour. The model considers the mechano-electrochemical events as concurrent phenomena in a three-dimensional environment. This model has been extended here to include the effect of repulsion of negative charges attached to proteoglycans. Moreover, we have studied the fluctuation of these charges owning to proteoglycan variations in healthy and pathological articular cartilage. In this sense, standard patterns of healthy and degraded tissue behaviour can be obtained which could be a helpful diagnostic tool. By introducing measured properties of unhealthy cartilage into the computational model, the severity of tissue degeneration can be predicted avoiding complex tissue extraction and subsequent in vitro analysis. In this work, the model has been applied to monitor and analyse cartilage behaviour at different stages of OA and in both short (four, six and eight weeks) and long-term (11 weeks) fully immobilized joints. Simulation results showed marked differences in the corresponding swelling phenomena, in outgoing cation fluxes and in cation distributions. Furthermore, long-term immobilized patients display similar swelling as well as fluxes and distribution of cations to patients in the early stages of OA, thus, preventive treatments are highly recommended to avoid tissue deterioration. PMID:25392400

  4. Finite difference time domain model of ultrasound propagation in agarose scaffold containing collagen or chondrocytes.

    Science.gov (United States)

    Inkinen, Satu I; Liukkonen, Jukka; Malo, Markus K H; Virén, Tuomas; Jurvelin, Jukka S; Töyräs, Juha

    2016-07-01

    Measurement of ultrasound backscattering is a promising diagnostic technique for arthroscopic evaluation of articular cartilage. However, contribution of collagen and chondrocytes on ultrasound backscattering and speed of sound in cartilage is not fully understood and is experimentally difficult to study. Agarose hydrogels have been used in tissue engineering applications of cartilage. Therefore, the aim of this study was to simulate the propagation of high frequency ultrasound (40 MHz) in agarose scaffolds with varying concentrations of chondrocytes (1 to 32 × 10(6) cells/ml) and collagen (1.56-200 mg/ml) using transversely isotropic two-dimensional finite difference time domain method (FDTD). Backscatter and speed of sound were evaluated from the simulated pulse-echo and through transmission measurements, respectively. Ultrasound backscatter increased with increasing collagen and chondrocyte concentrations. Furthermore, speed of sound increased with increasing collagen concentration. However, this was not observed with increasing chondrocyte concentrations. The present study suggests that the FDTD method may have some applicability in simulations of ultrasound scattering and propagation in constructs containing collagen and chondrocytes. Findings of this study indicate the significant role of collagen and chondrocytes as ultrasound scatterers and can aid in development of modeling approaches for understanding how cartilage architecture affects to the propagation of high frequency ultrasound. PMID:27475127

  5. Inhibition of β-catenin signaling causes defects in postnatal cartilage development

    OpenAIRE

    Chen, Mo; Zhu, Mei; Awad, Hani; Li, Tian-Fang; Sheu, Tzong-Jen; Boyce, Brendan F; Chen, Di; O'Keefe, Regis J.

    2008-01-01

    The Wnt/β-catenin signaling pathway is essential for normal skeletal development because conditional gain or loss of function of β-catenin in cartilage results in embryonic or early postnatal death. To address the role of β-catenin in postnatal skeletal growth and development, Col2a1-ICAT transgenic mice were generated. Mice were viable and had normal size at birth, but became progressively runted. Transgene expression was limited to the chondrocytes in the growth plate and articular cartilag...

  6. Cartilage-selective genes identified in genome-scale analysis of non-cartilage and cartilage gene expression

    Directory of Open Access Journals (Sweden)

    Cohn Zachary A

    2007-06-01

    Full Text Available Abstract Background Cartilage plays a fundamental role in the development of the human skeleton. Early in embryogenesis, mesenchymal cells condense and differentiate into chondrocytes to shape the early skeleton. Subsequently, the cartilage anlagen differentiate to form the growth plates, which are responsible for linear bone growth, and the articular chondrocytes, which facilitate joint function. However, despite the multiplicity of roles of cartilage during human fetal life, surprisingly little is known about its transcriptome. To address this, a whole genome microarray expression profile was generated using RNA isolated from 18–22 week human distal femur fetal cartilage and compared with a database of control normal human tissues aggregated at UCLA, termed Celsius. Results 161 cartilage-selective genes were identified, defined as genes significantly expressed in cartilage with low expression and little variation across a panel of 34 non-cartilage tissues. Among these 161 genes were cartilage-specific genes such as cartilage collagen genes and 25 genes which have been associated with skeletal phenotypes in humans and/or mice. Many of the other cartilage-selective genes do not have established roles in cartilage or are novel, unannotated genes. Quantitative RT-PCR confirmed the unique pattern of gene expression observed by microarray analysis. Conclusion Defining the gene expression pattern for cartilage has identified new genes that may contribute to human skeletogenesis as well as provided further candidate genes for skeletal dysplasias. The data suggest that fetal cartilage is a complex and transcriptionally active tissue and demonstrate that the set of genes selectively expressed in the tissue has been greatly underestimated.

  7. Del1 Knockout Mice Developed More Severe Osteoarthritis Associated with Increased Susceptibility of Chondrocytes to Apoptosis

    Science.gov (United States)

    Wang, Zhen; Tran, Misha C.; Bhatia, Namrata J.; Hsing, Alexander W.; Chen, Carol; LaRussa, Marie F.; Fattakhov, Ernst; Rashidi, Vania; Jang, Kyu Yun; Choo, Kevin J.; Nie, Xingju; Mathy, Jonathan A.; Longaker, Michael T.; Dauskardt, Reinhold H.; Helms, Jill A.; Yang, George P.

    2016-01-01

    Objective We identified significant expression of the matricellular protein, DEL1, in hypertrophic and mature cartilage during development. We hypothesized that this tissue-specific expression indicated a biological role for DEL1 in cartilage biology. Methods Del1 KO and WT mice had cartilage thickness evaluated by histomorphometry. Additional mice underwent medial meniscectomy to induce osteoarthritis, and were assayed at 1 week for apoptosis by TUNEL staining and at 8 weeks for histology and OA scoring. In vitro proliferation and apoptosis assays were performed on primary chondrocytes. Results Deletion of the Del1 gene led to decreased amounts of cartilage in the ears and knee joints in mice with otherwise normal skeletal morphology. Destabilization of the knee led to more severe OA compared to controls. In vitro, DEL1 blocked apoptosis in chondrocytes. Conclusion Osteoarthritis is among the most prevalent diseases worldwide and increasing in incidence as our population ages. Initiation begins with an injury resulting in the release of inflammatory mediators. Excessive production of inflammatory mediators results in apoptosis of chondrocytes. Because of the limited ability of chondrocytes to regenerate, articular cartilage deteriorates leading to the clinical symptoms including severe pain and decreased mobility. No treatments effectively block the progression of OA. We propose that direct modulation of chondrocyte apoptosis is a key variable in the etiology of OA, and therapies aimed at preventing this important step represent a new class of regenerative medicine targets. PMID:27505251

  8. Articular cartilage damage with intramedullary lesion (bone bruise) in anterior cruciate ligament rupture

    International Nuclear Information System (INIS)

    We evaluated the relationship between the intramedullary lesion on MRI and cartilage damage in patients associated with acute anterior cruciate ligament (ACL) rupture. Thirty-two cases documented by MRI and arthroscopy within one month from injury underwent ACL reconstruction using ST-G, and arthroscopy was performed again after surgery. The mean term between reconstruction and postoperative arthroscopy was twelve months. The cartilage damage on arthroscopy was compared with the intramedullary lesion on MRI. Cartilage damage was observed in 9 cases (28.1%) during the initial arthroscopy and in 16 cases (50.0%) during the second arthroscopy. Intramedullary lesion was detected in all 32 cases (total: 73 lesions) on MRI. Intramedullary lesion leading to cartilage damage was common in the geographic-type lateral femoral condyle. There was significant difference between the lateral meniscus tear and the cartilage damage of the lateral compartment. (author)

  9. Articular cartilage damage with intramedullary lesion (bone bruise) in anterior cruciate ligament rupture

    Energy Technology Data Exchange (ETDEWEB)

    Ide, Shuya; Ohdera, Toshihiro; Tokunaga, Masami; Hiroshima, Shiro; Yoshimoto, Eiji [Fukuoka Orthopaedic Hospital (Japan)

    2002-09-01

    We evaluated the relationship between the intramedullary lesion on MRI and cartilage damage in patients associated with acute anterior cruciate ligament (ACL) rupture. Thirty-two cases documented by MRI and arthroscopy within one month from injury underwent ACL reconstruction using ST-G, and arthroscopy was performed again after surgery. The mean term between reconstruction and postoperative arthroscopy was twelve months. The cartilage damage on arthroscopy was compared with the intramedullary lesion on MRI. Cartilage damage was observed in 9 cases (28.1%) during the initial arthroscopy and in 16 cases (50.0%) during the second arthroscopy. Intramedullary lesion was detected in all 32 cases (total: 73 lesions) on MRI. Intramedullary lesion leading to cartilage damage was common in the geographic-type lateral femoral condyle. There was significant difference between the lateral meniscus tear and the cartilage damage of the lateral compartment. (author)

  10. Influence of osteoarthritis grade on molecular signature of human cartilage.

    Science.gov (United States)

    Zhou, Shuanhu; Thornhill, Thomas S; Meng, Fangang; Xie, Li; Wright, John; Glowacki, Julie

    2016-03-01

    Articular chondrocytes maintain cartilage matrix turnover and have the capacity for anabolic and catabolic activities that can be influenced by injury and disease. This study tested the hypothesis that catabolic genes are upregulated with regional osteoarthritis (OA) disease severity within a joint. With IRB approval, specimens of knee cartilage obtained as discarded tissues from subjects undergoing arthroplasty were partitioned for each subject by OA disease severity and evaluated for gene expression by RT-PCR. There was regional OA grade-associated upregulation of expected inflammatory mediators TNF-α, TNF receptors, IFN-γ, and interleukins as well as genes encoding proteolytic enzymes, including Adamts-5 and MMPs. Osteoclast-related genes, cathepsin K, tartrate-resistant acid phosphatase (TRAP), RANKL, RANK, M-CSF, and c-fms, but not osteoprotegerin, were induced in advanced grades. In vitro treatment of normal human chondrocytes with interleukin-1β upregulated similar genes; this provides evidence that chondrocytes per se can be the source of osteoclast-related factors. Immunohistochemical staining showed that RANK- and RANKL-positive cells were abundant in advanced grades, especially in chondrocyte clusters. This suggests a possible autocrine mechanism by which an osteoclast phenotype is induced in articular chondrocytes. In sum, these studies identified gene expression signatures in human OA cartilage based upon regional disease severity within a joint. There was an effect of OA Grade on expression of osteoclastic lytic enzymes and regulatory factors in human articular chondrocytes. Induction of an osteoclast-like phenotype in chondrocytes may be part of OA progression and suggests specific therapeutic approaches. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:454-462, 2016. PMID:26336057

  11. Gremlin 1, frizzled-related protein, and Dkk-1 are key regulators of human articular cartilage homeostasis: Article recommendation on F1000Prime

    NARCIS (Netherlands)

    Leijten, J.C.H.; Emons, J.; Sticht, C.; Gool, van S.; Decker, E.; Uitterlinden, A.; Rappold, G.; Hofman, A.; Rivadeneira, F.; Scherjon, S.; Wit, J.M.; Meurs, van J.; Blitterswijk, van C.A.; Karperien, H.B.J.

    2012-01-01

    By using wide transcriptome analysis, these authors unraveled distinct fingerprints for human articular and growth plate cartilage and identified bone morphogenetic protein (BMP) and Wnt signaling inhibitors (GREM1, FRZB and DKK1) as the most differentially expressed. Furthermore, they confirmed the

  12. Tailored PVA/ECM Scaffolds for Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    Elena Stocco

    2014-01-01

    Full Text Available Articular cartilage lesions are a particular challenge for regenerative medicine due to cartilage low self-ability repair in case of damage. Hence, a significant goal of musculoskeletal tissue engineering is the development of suitable structures in virtue of their matrix composition and biomechanical properties. The objective of our study was to design in vitro a supporting structure for autologous chondrocyte growth. We realized a biohybrid composite scaffold combining a novel and nonspecific extracellular matrix (ECM, which is decellularized Wharton’s jelly ECM, with the biomechanical properties of the synthetic hydrogel polyvinyl alcohol (PVA. Wharton’s jelly ECM was tested for its ability in promoting scaffold colonization by chondrocytes and compared with polyvinyl alcohol itself and the more specific decellularized cartilage matrix. Our preliminary evidences highlighted the chance of using Wharton’s jelly ECM in combination with PVA hydrogels as an innovative and easily available scaffold for cartilage restoration.

  13. PEP-1-FK506BP12 inhibits matrix metalloproteinase expression in human articular chondrocytes and in a mouse carrageenan-induced arthritis model.

    Science.gov (United States)

    Hwang, Hyun Sook; Park, In Young; Kim, Dae Won; Choi, Soo Young; Jung, Young Ok; Kim, Hyun Ah

    2015-07-01

    The 12 kDa FK506-binding protein (FK506BP12), an immunosuppressor, modulates T cell activation via calcineurin inhibition. In this study, we investigated the ability of PEP-1-FK506BP12, consisting of FK506BP12 fused to the protein transduction domain PEP-1 peptide, to suppress catabolic responses in primary human chondrocytes and in a mouse carrageenan-induced paw arthritis model. Western blotting and immunofluorescence analysis showed that PEP-1-FK506BP12 efficiently penetrated chondrocytes and cartilage explants. In interleukin-1β (IL-1β)-treated chondrocytes, PEP-1-FK506BP12 significantly suppressed the expression of catabolic enzymes, including matrix metalloproteinases (MMPs)-1, -3, and -13 in addition to cyclooxygenase-2, at both the mRNA and protein levels, whereas FK506BP12 alone did not. In addition, PEP-1-FK506BP12 decreased IL-1β-induced phosphorylation of the mitogen-activated protein kinase (MAPK) complex (p38, JNK, and ERK) and the inhibitor kappa B alpha. In the mouse model of carrageenan-induced paw arthritis, PEP-1-FK506BP12 suppressed both carrageenan-induced MMP-13 production and paw inflammation. PEP-1-FK506BP12 may have therapeutic potential in the alleviation of OA progression. PMID:25887750

  14. Delayed Gadolinium-Enhanced Magnetic Resonance Imaging (dGEMRIC) of Hip Joint Cartilage: Better Cartilage Delineation after Intra-Articular than Intravenous Gadolinium Injection

    DEFF Research Database (Denmark)

    Boesen, M.; Jensen, K.E.; Quistgaard, E.; Danneskiold-Samsøe, B.; Thomsen, C.; Østergaard, Mikkel; Bliddal, H.

    2006-01-01

    PURPOSE: To investigate and compare delayed gadolinium (Gd-DTPA)-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in the hip joint using intravenous (i.v.) or ultrasound-guided intra-articular (i.a.) Gd-DTPA injection. MATERIAL AND METHODS: In 10 patients (50% males, mean age 58...... years) with clinical and radiographic hip osteoarthritis (OA; Kellgren score II-III), MRI of the hip was performed twice on a clinical 1.5T MR scanner: On day 1, before and 90-180 min after 0.3 mmol/kg body weight i.v. Gd-DTPA and, on day 8, 90-180 min after ultrasound-guided i.a. injection of a 4 mmol....../l Gd-DTPA solution. Coronal STIR, coronal T1 fat-saturated spin-echo, and a cartilage-sensitive gradient-echo sequence (3D T1 SPGR) in the sagittal plane were applied. RESULTS Both the post-i.v. and post-i.a. Gd-DTPA images showed significantly higher signal-to-noise (SNR) and contrast-to-noise (CNR...

  15. Tissue engineering of cartilage in space

    OpenAIRE

    Freed, Lisa E.; Langer, Robert; Martin, Ivan; Pellis, Neal R.; Vunjak-Novakovic, Gordana

    1997-01-01

    Tissue engineering of cartilage, i.e., the in vitro cultivation of cartilage cells on synthetic polymer scaffolds, was studied on the Mir Space Station and on Earth. Specifically, three-dimensional cell-polymer constructs consisting of bovine articular chondrocytes and polyglycolic acid scaffolds were grown in rotating bioreactors, first for 3 months on Earth and then for an additional 4 months on either Mir (10−4–10−6 g) or Earth (1 g). This mission provided a unique opportunity to study the...

  16. Enzymatic digestion of articular cartilage results in viscoelasticity changes that are consistent with polymer dynamics mechanisms

    Directory of Open Access Journals (Sweden)

    June Ronald K

    2009-11-01

    Full Text Available Abstract Background Cartilage degeneration via osteoarthritis affects millions of elderly people worldwide, yet the specific contributions of matrix biopolymers toward cartilage viscoelastic properties remain unknown despite 30 years of research. Polymer dynamics theory may enable such an understanding, and predicts that cartilage stress-relaxation will proceed faster when the average polymer length is shortened. Methods This study tested whether the predictions of polymer dynamics were consistent with changes in cartilage mechanics caused by enzymatic digestion of specific cartilage extracellular matrix molecules. Bovine calf cartilage explants were cultured overnight before being immersed in type IV collagenase, bacterial hyaluronidase, or control solutions. Stress-relaxation and cyclical loading tests were performed after 0, 1, and 2 days of incubation. Results Stress-relaxation proceeded faster following enzymatic digestion by collagenase and bacterial hyaluronidase after 1 day of incubation (both p ≤ 0.01. The storage and loss moduli at frequencies of 1 Hz and above were smaller after 1 day of digestion by collagenase and bacterial hyaluronidase (all p ≤ 0.02. Conclusion These results demonstrate that enzymatic digestion alters cartilage viscoelastic properties in a manner consistent with polymer dynamics mechanisms. Future studies may expand the use of polymer dynamics as a microstructural model for understanding the contributions of specific matrix molecules toward tissue-level viscoelastic properties.

  17. An in vitro comparative study of T2 and T2* mappings of human articular cartilage at 3-Tesla MRI using histology as the standard of reference

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the correlations between T2 value, T2* value, and histological grades of degenerated human articular cartilage. T2 mapping and T2* mapping of nine tibial osteochondral specimens were obtained using a 3-T MRI after total knee arthroplasty. A total of 94 ROIs were analyzed. Histological grades were assessed using the David-Vaudey scale. Spearman's rho correlation analysis and Pearson's correlation analysis were performed. The mean relaxation values in T2 map with different histological grades (0, 1, 2) of the cartilage were 51.9 ± 9.2 ms, 55.8 ± 12.8 ms, and 59.6 ± 10.2 ms, respectively. The mean relaxation values in T2* map with different histological grades (0, 1, 2) of the cartilage were 20.3 ± 10.3 ms, 21.1 ± 12.4 ms, and 15.4 ± 8.5 ms, respectively. Spearman's rho correlation analysis confirmed a positive correlation between T2 value and histological grade (ρ = 0.313, p < 0.05). Pearson's correlation analysis revealed a significant negative correlation between T2 and T2* (r = -0.322, p < 0.05). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, this correlation was not statistically significant in this study (ρ = -0.192, p = 0.129). T2 mapping was correlated with histological degeneration, and it may be a good biomarker for osteoarthritis in human articular cartilage. However, the strength of the correlation was weak (ρ = 0.313). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, the correlation was not statistically significant. Therefore, T2 mapping may be more appropriate for the initial diagnosis of articular cartilage degeneration in the knee joint. Further studies on T2* mapping are needed to confirm its reliability and mechanism in cartilage degeneration. (orig.)

  18. In vivo cartilage regeneration induced by a double-network hydrogel: Evaluation of a novel therapeutic strategy for femoral articular cartilage defects in a sheep model.

    Science.gov (United States)

    Kitamura, Nobuto; Yokota, Masashi; Kurokawa, Takayuki; Gong, Jian Ping; Yasuda, Kazunori

    2016-09-01

    The purpose of this study was to establish the efficacy of a therapeutic strategy for an articular cartilage defect using a poly-(2-acrylamido-2-methylpropanesulfonic acid)/poly-(N,N'-dimethyl acrylamide) DN gel in a sheep model. Seventeen mature sheep were used in this study. We created a 6.0-mm osteochondral defect in the femoral trochlea of the patellofemoral (PF) joint and the medial condyle of the tibiofemoral (TF) joint. A cylindrical DN gel plug was implanted into the defect of the right knee so that a vacant space of the planned depths of 2.0 mm in group I, 3.0 mm in group II, and 4.0 mm in group III were left. In the left knee, we created a defect with the same depth as the right knee. The regenerated tissues were evaluated with the O'Driscoll score and real-time PCR analysis of the cartilage marker genes at 12 weeks. The DN gel implanted defect of group II in the PF and TF joints was completely filled with a sufficient volume of the proteoglycan-rich tissue stained with Safranin-O. The score showed that group II was significantly greater than groups I and III when treated with DN gel in the PF joint (p = 0.0441, p = 0.0174, respectively) and in the TF joint (p = 0.0019, p = 0.0006, respectively). This study has clarified the short-term efficacy of the cartilage regeneration strategy using the DN gel in a sheep model. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2159-2165, 2016. PMID:27087198

  19. Nanopolymers Delivery of the Bone Morphogenetic Protein-4 Plasmid to Mesenchymal Stem Cells Promotes Articular Cartilage Repair In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Junjun Shi

    2012-01-01

    Full Text Available The clinical application of viral vectors for gene therapy is limited for biosafety consideration. In this study, to promote articular cartilage repair, poly (lactic-co glycolic acid (PLGA nanopolymers were used as non-viral vectors to transfect rabbit mesenchymal stem cells (MSCs with the pDC316-BMP4-EGFP plasmid. The cytotoxicity and transfection efficiency in vitro were acceptable measuring by CCK-8 and flow cytometry. After transfection, Chondrogenic markers (mRNA of Col2a1, Sox9, Bmp4, and Agg of experimental cells (MSCs being transfected with BMP-4 plasmid by PLGA nanopolymers were increased more than those of control cells (MSCs being transfected with naked BMP-4 plasmid alone. In vivo study, twelve rabbits (24 knees with large full thickness articular cartilage defects were randomly divided into the experimental group (MSCs being transfected with BMP-4 plasmid by PLGA nanopolymers and the control group (MSCs being transfected with naked BMP-4 plasmid. The experimental group showed better regeneration than the control group 6 and 12 weeks postoperatively. Hyaline-like cartilage formed at week 12 in the experimental group, indicating the local delivery of BMP-4 plasmid to MSCs by PLGA nanopolymers improved articular cartilage repair significantly. PLGA nanopolymers could be a promising and effective non-viral vector for gene therapy in cartilage repair.

  20. Initial results of in vivo high-resolution morphological and biochemical cartilage imaging of patients after matrix-associated autologous chondrocyte transplantation (MACT) of the ankle

    International Nuclear Information System (INIS)

    The aim of this study was to use morphological as well as biochemical (T2 and T2* relaxation times and diffusion-weighted imaging (DWI)) magnetic resonance imaging (MRI) for the evaluation of healthy cartilage and cartilage repair tissue after matrix-associated autologous chondrocyte transplantation (MACT) of the ankle joint. Ten healthy volunteers (mean age, 32.4 years) and 12 patients who underwent MACT of the ankle joint (mean age, 32.8 years) were included. In order to evaluate possible maturation effects, patients were separated into short-term (6-13 months) and long-term (20-54 months) follow-up cohorts. MRI was performed on a 3.0-T magnetic resonance (MR) scanner using a new dedicated eight-channel foot-and-ankle coil. Using high-resolution morphological MRI, the magnetic resonance observation of cartilage repair tissue (MOCART) score was assessed. For biochemical MRI, T2 mapping, T2* mapping, and DWI were obtained. Region-of-interest analysis was performed within native cartilage of the volunteers and control cartilage as well as cartilage repair tissue in the patients subsequent to MACT. The overall MOCART score in patients after MACT was 73.8. T2 relaxation times (∝50 ms), T2* relaxation times (∝16 ms), and the diffusion constant for DWI (∝1.3) were comparable for the healthy volunteers and the control cartilage in the patients after MACT. The cartilage repair tissue showed no significant difference in T2 and T2* relaxation times (p≥0.05) compared to the control cartilage; however, a significantly higher diffusivity (∝1.5; p<0.05) was noted in the cartilage repair tissue. The obtained results suggest that besides morphological MRI and biochemical MR techniques, such as T2 and T2* mapping, DWI may also deliver additional information about the ultrastructure of cartilage and cartilage repair tissue in the ankle joint using high-field MRI, a dedicated multichannel coil, and sophisticated sequences. (orig.)

  1. Incorporation of hyaluronic acid into collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Tang Shunqing [Department of Biomedical Engineering, Jinan University, Guangzhou 510632 (China); Spector, Myron [Tissue Engineering, VA Boston Healthcare System, Boston, MA 02130 (United States)

    2007-09-15

    Hyaluronic acid (HA), a principal matrix molecule in many tissues, is present in high amounts in articular cartilage. HA contributes in unique ways to the physical behavior of the tissue, and has been shown to have beneficial effects on chondrocyte activity. The goal of this study was to incorporate graduated amounts of HA into type I collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis in vitro. The results demonstrated that the amount of contraction of HA/collagen scaffolds by adult canine articular chondrocytes increased with the HA content of the scaffolds. The greatest amount of chondrogenesis after two weeks was found in the scaffolds which had undergone the most contraction. HA can play a useful role in adjusting the mechanical behavior of tissue engineering scaffolds and chondrogenesis in chondrocyte-seeded scaffolds.

  2. Incorporation of hyaluronic acid into collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis

    International Nuclear Information System (INIS)

    Hyaluronic acid (HA), a principal matrix molecule in many tissues, is present in high amounts in articular cartilage. HA contributes in unique ways to the physical behavior of the tissue, and has been shown to have beneficial effects on chondrocyte activity. The goal of this study was to incorporate graduated amounts of HA into type I collagen scaffolds for the control of chondrocyte-mediated contraction and chondrogenesis in vitro. The results demonstrated that the amount of contraction of HA/collagen scaffolds by adult canine articular chondrocytes increased with the HA content of the scaffolds. The greatest amount of chondrogenesis after two weeks was found in the scaffolds which had undergone the most contraction. HA can play a useful role in adjusting the mechanical behavior of tissue engineering scaffolds and chondrogenesis in chondrocyte-seeded scaffolds

  3. Quantitative T2 mapping evaluation for articular cartilage lesions in a rabbit model of anterior cruciate ligament transection osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    WEI Zheng-mao; DU Xiang-ke; HUO Tian-long; LI Xu-bin; QUAN Guang-nan; LI Tian-ran; CHENG Jin; ZHANG Wei-tao

    2012-01-01

    Background Quantitative T2 mapping has been a widely used method for the evaluation of pathological cartilage properties,and the histological assessment system of osteoarthritis in the rabbit has been published recently.The aim of the study was to investigate the effectiveness of quantitative T2 mapping evaluation for articular cartilage lesions of a rabbit model of anterior cruciate ligament transection (ACLT) osteoarthritis.Methods Twenty New Zealand White (NZW) rabbits were divided into ACLT surgical group and sham operated group equally.The anterior cruciate ligaments of the rabbits in ACLT group were transected,while the joints were closed intactly in sham operated group.Magnetic resonance (MR) examinations were performed on 3.0T MR unit at week 0,week 6,and week 12.T2 values were computed on GE ADW4.3 workstation.All rabbits were killed at week 13,and left knees were stained with Haematoxylin and Eosin.Semiquantitative histological grading was obtained according to the osteoarthritis cartilage histopathology assessment system.Computerized image analysis was performed to quantitate the immunostained collagen type Ⅱ.Results The average MR T2 value of whole left knee cartilage in ACLT surgical group ((29.05±12.01) ms) was significantly higher than that in sham operated group ((24.52±7.97) ms) (P=0.024) at week 6.The average T2 value increased to (32.18±12.79) ms in ACLT group at week 12,but remained near the baseline level ((27.66±8.08) ms) in the sham operated group (P=0.03).The cartilage lesion level of left knee in ACLT group was significantly increased at week 6 (P=0.005) and week 12 (P <0.001).T2 values had positive correlation with histological grading scores,but inverse correlation with optical densities (OD) of type Ⅱ collagen.Conclusion This study demonstrated the reliability and practicability of quantitative T2 mapping for the cartilage injury of rabbit ACLT osteoarthritis model.

  4. Second-look arthroscopic evaluation of the articular cartilage after primary single-bundle and double-bundle anterior cruciate ligament reconstructions

    Institute of Scientific and Technical Information of China (English)

    WANG Hai-jun; AO Ying-fang; CHEN Lian-xu; GONG Xi; WANG Yong-jian; MAYong; LEUNG Kevin; Kar Ming; YU Jia-kuo

    2011-01-01

    Background Several reports have shown the progression of articular cartilage degeneration after anterior cruciate ligament (ACL) reconstruction.No report has been published about the cartilage comparing changes after single-bundle (SB) and double-bundle (DB) ACL reconstructions.The purpose of this study was to evaluate the articular cartilage changes after SB and DB ACL reconstructions by second-look arthroscopy.Methods Ninety-nine patients who received arthroscopic ACL reconstruction were retrospectively reviewed at an average of 14 months after reconstruction,58 patients underwent SB ACL reconstruction and 41 patients underwent DB ACL reconstruction.Hamstring tendon autografts were used in all patients.Second-look arthroscopy was done in conjunction with the tibial staple fixation removal at least one year after the initial ACL reconstruction.Arthroscopic evaluation and grading of the articular cartilage degeneration for all patients were performed at the initial ACL reconstruction,and at the second-look arthroscopy.Results The average cartilage degeneration at the patellofemoral joint (PFJ) was found significantly worsened after both SB and DB ACL reconstructions.This worsening were not seen at medial tibiofemoral joint (TFJ) and lateral TFJ.Grade Ⅱ cartilage damage was the most common.At second-look arthroscopy,the average patellar cartilage degeneration was 1.14±0.14 (at first look 0.52±0.11) for the SB group,and 1.22±0.15 (at first look 0.56±0.12) for the DB group.The average trochlear cartilage degeneration was 1.05±0.16 (at fist look 0.10±0.06) and 0.66±0.17 (at fist look 0.17±0.09),respectively.The average patellar cartilage degeneration showed no significant difference in both groups.However,the average trochlea cartilage degeneration in DB group was significantly less than in SB group.Conclusions Patellofemoral cartilage degeneration continued to aggravate after ACL reconstruction.DB ACL reconstruction could significantly decrease the trochlea

  5. Mesenchymal stem cells promote articular cartilage repair and regeneration%间充质干细胞促进关节软骨的修复与再生

    Institute of Scientific and Technical Information of China (English)

    朱瑜琪; 王金荣; 王智耀

    2015-01-01

    背景:关节软骨损伤后,软骨组织几乎没有修复能力,关节软骨损伤的修复一直是临床工作的难点。  目的:探讨修复关节软骨损伤的干细胞种类及其生物学特性,明确干细胞在修复关节软骨损伤中的作用及优缺点。  方法:由第一作者检索1998至2015年PubMed数据及CNKI中国期刊全文数据库,英文检索词“Articular cartilage injury,Mesenchymal stem cels,regeneration”;中文检索词“关节软骨损伤,间充质干细胞,再生”,纳入47篇文献进行分析。  结果与结论:关节软骨损伤最有效的修复方案是以细胞为基础的治疗方法,来源于骨髓、脂肪及脐血的间充质干细胞均有较强的成软骨特性和克隆能力。骨髓间充质干细胞具有更高的分化潜能,对软骨缺损有修复作用,来源于脐血的间充质干细胞致瘤性低,脂肪源性干细胞的生长增殖速度更快。干细胞复合天然载体材料如胶原、明胶、纤维蛋白和藻酸盐等可促进细胞黏附、分化和增殖,以此构建组织工程软骨将有效修复关节软骨缺损。%BACKGROUND:After articular cartilage injury, the injured cartilage almost has no self-healing ability. Articular cartilage injury repair has been always a difficulty in clinical work. OBJECTIVE:To explore the types and biological characteristics of stem cels for articular cartilage repair and to ensure the role and relative merits of stem cel transplantation in articular cartilage repair. METHODS:PubMed and CNKI were retrieved by the first author for relevant articles published from 1998 to 2015 using the keywords of “articular cartilage injury, mesenchymal stem cels, regeneration” in English and Chinese, respectively. Finaly, 47 articles were included in result analysis. RESULTS AND CONCLUSION: Stem cel therapy is the most effective method for repair of articular cartilage injury. Mesenchymal stem cels from bone

  6. Microstructural modeling of collagen network mechanics and interactions with the proteoglycan gel in articular cartilage.

    Science.gov (United States)

    Quinn, T M; Morel, V

    2007-01-01

    Cartilage matrix mechanical function is largely determined by interactions between the collagen fibrillar network and the proteoglycan gel. Although the molecular physics of these matrix constituents have been characterized and modern imaging methods are capable of localized measurement of molecular densities and orientation distributions, theoretical tools for using this information for prediction of cartilage mechanical behavior are lacking. We introduce a means to model collagen network contributions to cartilage mechanics based upon accessible microstructural information (fibril density and orientation distributions) and which self-consistently follows changes in microstructural geometry with matrix deformations. The interplay between the molecular physics of the collagen network and the proteoglycan gel is scaled up to determine matrix material properties, with features such as collagen fibril pre-stress in free-swelling cartilage emerging naturally and without introduction of ad hoc parameters. Methods are developed for theoretical treatment of the collagen network as a continuum-like distribution of fibrils, such that mechanical analysis of the network may be simplified by consideration of the spherical harmonic components of functions of the fibril orientation, strain, and stress distributions. Expressions for the collagen network contributions to matrix stress and stiffness tensors are derived, illustrating that only spherical harmonic components of orders 0 and 2 contribute to the stress, while orders 0, 2, and 4 contribute to the stiffness. Depth- and compression-dependent equilibrium mechanical properties of cartilage matrix are modeled, and advantages of the approach are illustrated by exploration of orientation and strain distributions of collagen fibrils in compressed cartilage. Results highlight collagen-proteoglycan interactions, especially for very small physiological strains where experimental data are relatively sparse. These methods for

  7. Studies of the articular cartilage proteoglycan aggrecan in health and osteoarthritis. Evidence for molecular heterogeneity and extensive molecular changes in disease.

    Science.gov (United States)

    Rizkalla, G; Reiner, A; Bogoch, E; Poole, A R

    1992-01-01

    Changes in the structure of the proteoglycan aggrecan (PG) of articular cartilage were determined immunochemically by RIA and gel chromatography and related to cartilage degeneration documented histologically by the Mankin grading system. Monoclonal antibodies to glycosaminoglycan epitopes were used. In all cartilages, three chondroitin sulfate (CS)-rich populations of large size were observed in addition to a smaller keratan sulfate (KS)-rich population. In grades 7-13 OA cartilages (phase II), molecules were significantly larger than the equivalent molecules of grades 2-6 (phase I). CS chain lengths remained unchanged. In most OA cartilages, a CS epitope 846 was elevated in content, this being most marked in phase II (mean: fivefold). Loss of uronic acid, KS, and hyaluronic acid were only pronounced in phase II OA because of variations in normal contents. Aggregation of PG was unchanged (50-60%) or reduced in OA cartilages, but molecules bearing epitope 846 exhibited almost complete aggregation in normal cartilages. This study provides evidence for the capacity of OA cartilage to synthesize new aggrecan molecules to replace those damaged and lost by disease-related changes. It also defines two phases of PG change in OA: an early predominantly degenerate phase I followed by a net reparative phase II accompanied by net loss of these molecules. Images PMID:1281828

  8. The interplay between chondrocyte redifferentiation pellet size and oxygen concentration.

    Directory of Open Access Journals (Sweden)

    Betul Kul Babur

    Full Text Available Chondrocytes dedifferentiate during ex vivo expansion on 2-dimensional surfaces. Aggregation of the expanded cells into 3-dimensional pellets, in the presence of induction factors, facilitates their redifferentiation and restoration of the chondrogenic phenotype. Typically 1×10(5-5×10(5 chondrocytes are aggregated, resulting in "macro" pellets having diameters ranging from 1-2 mm. These macropellets are commonly used to study redifferentiation, and recently macropellets of autologous chondrocytes have been implanted directly into articular cartilage defects to facilitate their repair. However, diffusion of metabolites over the 1-2 mm pellet length-scales is inefficient, resulting in radial tissue heterogeneity. Herein we demonstrate that the aggregation of 2×10(5 human chondrocytes into micropellets of 166 cells each, rather than into larger single macropellets, enhances chondrogenic redifferentiation. In this study, we describe the development of a cost effective fabrication strategy to manufacture a microwell surface for the large-scale production of micropellets. The thousands of micropellets were manufactured using the microwell platform, which is an array of 360×360 µm microwells cast into polydimethylsiloxane (PDMS, that has been surface modified with an electrostatic multilayer of hyaluronic acid and chitosan to enhance micropellet formation. Such surface modification was essential to prevent chondrocyte spreading on the PDMS. Sulfated glycosaminoglycan (sGAG production and collagen II gene expression in chondrocyte micropellets increased significantly relative to macropellet controls, and redifferentiation was enhanced in both macro and micropellets with the provision of a hypoxic atmosphere (2% O2. Once micropellet formation had been optimized, we demonstrated that micropellets could be assembled into larger cartilage tissues. Our results indicate that micropellet amalgamation efficiency is inversely related to the time cultured as

  9. Viscoelastic properties of chondrons enzymatically isolated from rabbit knee articular cartilage in virto%兔膝关节软骨单位微管吸吮黏弹性力学分析

    Institute of Scientific and Technical Information of China (English)

    段王平; 孙振伟; 李琦; 郝永壮; 王立; 陈维毅; 卫小春

    2011-01-01

    目的 探讨体外急性消化软骨单位的生物力学特性.方法 成年8月龄新西兰白兔8只,随机分为两组,各4只.无菌条件下剖取双膝关节全层软骨,一组采用常规质量浓度0.4%的pronase酶和质量浓度0.025%的Ⅱ型胶原酶依次消化为软骨细胞;另一组采用质量浓度0.3%的dispase酶和质量浓度0.2%的Ⅱ型胶原酶联合搅拌消化3 h为软骨单位.利用微管吸吮结合半无限体细胞力学模型定量分析急性消化软骨细胞及软骨单位黏弹性力学特性,包括平衡模量(E∞)、瞬间模量(E0)和表观黏性(μ)等黏弹性参数.结果 成年软骨细胞在0.2-0.4 kPa恒定微管负压下,表现为典型黏弹性固体特征,即在微管中产生瞬间微小变形,随后发生形率单调减小的蠕变过程,其到达平衡状态时间为(110±18)s.成年软骨单位在微管吸吮负压提高到1.0~1.2 kPa时,与软骨细胞发生同样的黏弹性蠕变行为,但其瞬间吸入微管内的长度明显减少,且到达平衡状态的时间缩短为(36.5±4.5)s.同时,软骨单位黏弹性参数平衡模量(E∞)、瞬间模量(E0)和表观黏性(μ)均明显高于软骨细胞.结论 与软骨细胞相比,成年软骨单位同样表现为黏弹性固体特征,但其黏弹性力学特性明显提高.%Objective To characterize the biomechanical behavior and properties of the chondrons enzymatically isolated from rabbit knee articular cartilage in virto. Methods Eight months old New Zealand white rabbits were randomly divided into chondroctye and chondron groups (4 rabbits in each group). In chondrocyte groups, the full articular cartilages from both knees were enzymatically isolated to chondrocytes by 0.4% pronase and 0.025% collagenase type-Ⅱ in turn. In chondron groups, chondrons were obtained from articular cartilage using the mixture of 0.3% dispase (a neutral protease) and 0.2% collagenase type-Ⅱin at 37C for 3 h. The micropipette aspiration was used to quantify changes in

  10. The Effect of Chondroitin Sulphate and Hyaluronic Acid on Chondrocytes Cultured within a Fibrin-Alginate Hydrogel

    Directory of Open Access Journals (Sweden)

    Christopher J. Little

    2014-09-01

    Full Text Available Osteoarthritis is a painful degenerative joint disease that could be better managed if tissue engineers can develop methods to create long-term engineered articular cartilage tissue substitutes. Many of the tissue engineered cartilage constructs currently available lack the chemical stimuli and cell-friendly environment that promote the matrix accumulation and cell proliferation needed for use in joint cartilage repair. The goal of this research was to test the efficacy of using a fibrin-alginate hydrogel containing hyaluronic acid (HA and/or chondroitin sulphate (CS supplements for chondrocyte culture. Neonatal porcine chondrocytes cultured in fibrin-alginate hydrogels retained their phenotype better than chondrocytes cultured in monolayer, as evidenced by analysis of their relative expression of type II versus type I collagen mRNA transcripts. HA or CS supplementation of the hydrogels increased matrix glycosaminoglycan (GAG production during the first week of culture. However, the effects of these supplements on matrix accumulation were not additive and were no longer observed after two weeks of culture. Supplementation of the hydrogels with CS or a combination of both CS and HA increased the chondrocyte cell population after two weeks of culture. Statistical analysis indicated that the HA and CS treatment effects on chondrocyte numbers may be additive. This research suggests that supplementation with CS and/or HA has positive effects on cartilage matrix production and chondrocyte proliferation in three-dimensional (3D fibrin-alginate hydrogels.

  11. Studies of the humoral factors produced by layered chondrocyte sheets.

    Science.gov (United States)

    Hamahashi, K; Sato, M; Yamato, M; Kokubo, M; Mitani, G; Ito, S; Nagai, T; Ebihara, G; Kutsuna, T; Okano, T; Mochida, J

    2015-01-01

    The authors aimed to repair and regenerate articular cartilage with layered chondrocyte sheets, produced using temperature-responsive culture dishes. The purpose of this study was to investigate the humoral factors produced by layered chondrocyte sheets. Articular chondrocytes and synovial cells were harvested during total knee arthroplasty. After co-culture, the samples were divided into three groups: a monolayer, 7 day culture sheet group (group M); a triple-layered, 7 day culture sheet group (group L); and a monolayer culture group with a cell count identical to that of group L (group C). The secretion of collagen type 1 (COL1), collagen type 2 (COL2), matrix metalloproteinase-13 (MMP13), transforming growth factor-β (TGFβ), melanoma inhibitory activity (MIA) and prostaglandin E2 (PGE2) were measured by enzyme-linked immunosorbent assay (ELISA). Layered chondrocyte sheets produced the most humoral factors. PGE2 expression declined over time in group C but was significantly higher in groups M and L. TGFβ expression was low in group C but was significantly higher in groups M and L (p<0.05). Our results suggest that the humoral factors produced by layered chondrocyte sheets may contribute to cartilaginous tissue repair and regeneration. PMID:23165985

  12. Protein phosphorylation on tyrosine restores expression and glycosylation of cyclooxygenase-2 by 2-deoxy-D-glucose-caused endoplasmic reticulum stress in rabbit articular chondrocyte

    Directory of Open Access Journals (Sweden)

    Seon-Mi Yu

    2012-05-01

    Full Text Available 2-deoxy-D-glucose(2DG-caused endoplasmic reticulum (ERstress inhibits protein phosphorylation at tyrosine residues.However, the accurate regulatory mechanisms, which determinethe inflammatory response of chondrocytes to ER stress via proteintyrosine phosphorylation, have not been systematicallyevaluated. Thus, in this study, we examined whether proteinphosphorylation at tyrosine residues can modulate the expressionand glycosylation of COX-2, which is reduced by 2DG-inducedER stress. We observed that protein tyrosine phosphatase (PTP inhibitors,sodium orthovanadate (SOV, and phenylarsine oxide(PAO significantly decreased expression of ER stress inducibleproteins, glucose-regulated protein 94 (GRP94, and CCAAT/ enhancer-binding-protein- related gene (GADD153, which was inducedby 2DG. In addition, we demonstrated that SOV and PAOnoticeably restored the expression and glycosylation of COX-2 aftertreatment with 2DG. These results suggest that protein phosphorylationof tyrosine residues plays an important role in theregulation of expression and glycosylation during 2DG-inducedER stress in rabbit articular chondrocytes. [BMB reports 2012;45(5: 317-322

  13. Collagene order of articular cartilage by clinical magnetic resonance images and its age dependency

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, P.; Gruender, W. [Inst. of Medical Physics and Biophysics, Univ. of Leipzig (Germany)

    2005-07-01

    The present papers describes a novel method to obtain information on the degree of order of the collagen network of the knee meniscal cartilage by means of a single clinical MRI. Images were obtained from 34 healthy volunteers aged between 6 and 76 years as well as from one patient with clinically-diagnosed arthrosis at the age of 32 and 37 years. A siemens vision (1.5 T) MRT with TR = 750 ms, TE = 50 ms, FoV = 160 mm, and Matrix 512 x 512 was used for this purpose. The MR signal intensities of the cartilage were read out along slices with constant height above the subchondral bone and plotted versus the actual angle to the external magnetic field. The obtained intensity curves were fitted by a model distribution, and the degree of order of the collagen fibers was calculated. For the knee meniscal cartilage, there was an age-dependency of the degree of order and a significant deviation of the volunteer with arthrosis from the normal curve. The results are discussed in view of the arcade model and of a possible use of non-invasive clinical MRT for the detection of early arthrotic changes of cartilage. (orig.)

  14. Collagene order of articular cartilage by clinical magnetic resonance images and its age dependency

    International Nuclear Information System (INIS)

    The present papers describes a novel method to obtain information on the degree of order of the collagen network of the knee meniscal cartilage by means of a single clinical MRI. Images were obtained from 34 healthy volunteers aged between 6 and 76 years as well as from one patient with clinically-diagnosed arthrosis at the age of 32 and 37 years. A siemens vision (1.5 T) MRT with TR = 750 ms, TE = 50 ms, FoV = 160 mm, and Matrix 512 x 512 was used for this purpose. The MR signal intensities of the cartilage were read out along slices with constant height above the subchondral bone and plotted versus the actual angle to the external magnetic field. The obtained intensity curves were fitted by a model distribution, and the degree of order of the collagen fibers was calculated. For the knee meniscal cartilage, there was an age-dependency of the degree of order and a significant deviation of the volunteer with arthrosis from the normal curve. The results are discussed in view of the arcade model and of a possible use of non-invasive clinical MRT for the detection of early arthrotic changes of cartilage. (orig.)

  15. Debridement of cartilage lesions before autologous chondrocyte implantation by open or transarthroscopic techniques: a comparative study using post-mortem materials.

    Science.gov (United States)

    Drobnic, M; Radosavljevic, D; Cör, A; Brittberg, M; Strazar, K

    2010-04-01

    We compared the quality of debridement of chondral lesions performed by four arthroscopic (SH, shaver; CU, curette; SHCU, shaver and curette; BP, bipolar electrodes) and one open technique (OPEN, scalpel and curette) which are used prior to autologous chondrocyte implantation (ACI). The ex vivo simulation of all five techniques was carried out on six juvenile equine stifle joints. The OPEN, SH and SHCU techniques were tested on knees harvested from six adult human cadavers. The most vertical walls with the least adjacent damage to cartilage were obtained with the OPEN technique. The CU and SHCU methods gave inferior, but still acceptable results whereas the SH technique alone resulted in a crater-like defect and the BP method undermined the cartilage wall. The subchondral bone was severely violated in all the equine samples which might have been peculiar to this model. The predominant depth of the debridement in the adult human samples was at the level of the calcified cartilage. Some minor penetrations of the subchondral end-plate were induced regardless of the instrumentation used. Our study suggests that not all routine arthroscopic instruments are suitable for the preparation of a defect for ACI. We have shown that the preferred debridement technique is either open or arthroscopically-assisted manual curettage. The use of juvenile equine stifles was not appropriate for the study of the cartilage-subchondral bone interface. PMID:20357342

  16. The in vivo effects of unloading and compression on T1-Gd (dGEMRIC) relaxation times in healthy articular knee cartilage at 3.0 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Mayerhoefer, Marius E.; Kainberger, Franz; Weber, Michael; Nemec, Stefan; Friedrich, Klaus M.; Dirisamer, Albert; Trattnig, Siegfried [Medical University of Vienna, Department of Radiology, MR Center, Vienna (Austria); Welsch, Goetz H. [Medical University of Vienna, Department of Radiology, MR Center, Vienna (Austria); University of Erlangen, Department of Trauma Surgery, Erlangen (Germany); Mamisch, Tallal C. [University Bern, Department of Orthopaedic Surgery, Inselspital, Bern (Switzerland)

    2010-02-15

    The purpose was to investigate the in vivo effects of unloading and compression on T1-Gd relaxation times in healthy articular knee cartilage. Ten volunteers were enrolled, and dGEMRIC images of their right knee joints were obtained using 3.0-T MR at three timepoints: directly following exercise (''baseline''), approximately 15 min after unloading (''unloading'') and during application of a compressive force (50% of the body weight) generated by a loading device via a footplate (''compression''). Our analysis of variance of pooled data from all cartilage zones demonstrated a significant mean T1-Gd decrease of 56.6 ms between baseline and compression (p < 0.001), and a significant mean decrease of 42.1 ms between unloading and compression (p < 0.001). No significant difference was found between baseline and unloading. Higher mean T1-Gd values were observed in the cartilage contact zone (central femoral and tibial zones; 698.3 {+-} 162.2 ms) than in the non-contact zone (anterior and posterior femoral and tibial zones, and dorsal femoral zone; 662.9 {+-} 149.3 ms; p < 0.01). T1-Gd times appear to be sensitive to mechanical cartilage stress, and thus, further studies are warranted that investigate the relationship between the biochemical load response and the biomechanical properties of articular cartilage. (orig.)

  17. Impact of the charge density of phospholipid bilayers on lubrication of articular cartilage surfaces2O3-ZrO2(nano) (12 mol% CeO2) ceramics

    OpenAIRE

    Z. Pawlak; J. Kotynska; Figaszewski, Z A; A. Oloyede; A. Gadomski; A. Gudaniec

    2007-01-01

    Purpose: We attempt to answer the question how some changes in acid - base equilibrium have an impact on the charge density of a phospholipid bilayer formed during lubrication occurring at articular cartilage surfaces.Design/methodology/approach: Liposomes have been used to mimic biological phospholipid membranes on articular cartilage surface where proteins are bounded, ions are transported, energy is transducted, and cellular processes are taking place. The charge density of the membrane wa...

  18. Acetylation reduces SOX9 nuclear entry and ACAN gene transactivation in human chondrocytes.

    Science.gov (United States)

    Bar Oz, Michal; Kumar, Ashok; Elayyan, Jinan; Reich, Eli; Binyamin, Milana; Kandel, Leonid; Liebergall, Meir; Steinmeyer, Juergen; Lefebvre, Veronique; Dvir-Ginzberg, Mona

    2016-06-01

    Changes in the content of aggrecan, an essential proteoglycan of articular cartilage, have been implicated in the pathophysiology of osteoarthritis (OA), a prevalent age-related, degenerative joint disease. Here, we examined the effect of SOX9 acetylation on ACAN transactivation in the context of osteoarthritis. Primary chondrocytes freshly isolated from degenerated OA cartilage displayed lower levels of ACAN mRNA and higher levels of acetylated SOX9 compared with cells from intact regions of OA cartilage. Degenerated OA cartilage presented chondrocyte clusters bearing diffused immunostaining for SOX9 compared with intact cartilage regions. Primary human chondrocytes freshly isolated from OA knee joints were cultured in monolayer or in three-dimensional alginate microbeads (3D). SOX9 was hypo-acetylated in 3D cultures and displayed enhanced binding to a -10 kb ACAN enhancer, a result consistent with higher ACAN mRNA levels than in monolayer cultures. It also co-immunoprecipitated with SIRT1, a major deacetylase responsible for SOX9 deacetylation. Finally, immunofluorescence assays revealed increased nuclear localization of SOX9 in primary chondrocytes treated with the NAD SIRT1 cofactor, than in cells treated with a SIRT1 inhibitor. Inhibition of importin β by importazole maintained SOX9 in the cytoplasm, even in the presence of NAD. Based on these data, we conclude that deacetylation promotes SOX9 nuclear translocation and hence its ability to activate ACAN. PMID:26910618

  19. Combined role of type IX collagen and cartilage oligomeric matrix protein in cartilage matrix assembly: Cartilage oligomeric matrix protein counteracts type IX collagen-induced limitation of cartilage collagen fibril growth in mouse chondrocyte cultures

    NARCIS (Netherlands)

    Blumbach, K.; Bastiaansen-Jenniskens, Y.M.; Groot, J. de; Paulsson, M.; Osch, G.J.V.M. van; Zaucke, F.

    2009-01-01

    Objective. Defects in the assembly and composition of cartilage extracellular matrix are likely to result in impaired matrix integrity and increased susceptibility to cartilage degeneration. The aim of this study was to determine the functional interaction of the collagen fibril-associated proteins

  20. Characterization of chondrocyte sheets prepared using a co-culture method with temperature-responsive culture inserts.

    Science.gov (United States)

    Kokubo, Mami; Sato, Masato; Yamato, Masayuki; Mitani, Genya; Kutsuna, Toshiharu; Ebihara, Goro; Okano, Teruo; Mochida, Joji

    2016-06-01

    Conventional culture methods using temperature-responsive culture dishes require 4-5 weeks to prepare layered chondrocyte sheets that can be used in articular cartilage repair and regeneration. This study investigated whether the use of synovial tissue obtained from the same joint as the chondrocyte nutritive supply source could more quickly facilitate the preparation of chondrocyte sheets. After culturing derived synoviocytes and chondrocytes together (i.e. combined culture or co-culture) on temperature-responsive inserts, chondrocyte growth was assessed and a molecular analysis of the chondrocyte sheets was performed. Transplantable tissue could be obtained more quickly using this method (average 10.5 days). Real-time polymerase chain reaction and immunostaining of the three-layer chondrocyte sheets confirmed the significant expression of genes critical to cartilage maintenance, including type II collagen (COL2), aggrecan-1 and tissue metallopeptidase inhibitor 1. However, the expression of COL1, matrix metalloproteinase 3 (MMP3), MMP13 and A-disintegrin and metalloproteinase with thrombospondin motifs 5 was suppressed. The adhesive factor fibronectin-1 (FN1) was observed in all sheet layers, whereas in sheets generated using conventional preparation methods positive FN1 immunostaining was observed only on the surface of the sheets. The results indicate that synoviocyte co-cultures provide an optimal environment for the preparation of chondrocyte sheets for tissue transplantation and are particularly beneficial for shortening the required culture period. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23868865

  1. Mechanical Forces Induce Changes in VEGF and VEGFR-1/sFlt-1 Expression in Human Chondrocytes

    Directory of Open Access Journals (Sweden)

    Rainer Beckmann

    2014-09-01

    Full Text Available Expression of the pro-angiogenic vascular endothelial growth factor (VEGF stimulates angiogenesis and correlates with the progression of osteoarthritis. Mechanical joint loading seems to contribute to this cartilage pathology. Cyclic equibiaxial strains of 1% to 16% for 12 h, respectively, induced expression of VEGF in human chondrocytes dose- and frequency-dependently. Stretch-mediated VEGF induction was more prominent in the human chondrocyte cell line C-28/I2 than in primary articular chondrocytes. Twelve hours of 8% stretch induced VEGF expression to 175% of unstrained controls for at least 24 h post stretching, in promoter reporter and enzyme-linked immunosorbent assay (ELISA studies. High affinity soluble VEGF-receptor, sVEGFR-1/sFlt-1 was less stretch-inducible than its ligand, VEGF-A, in these cells. ELISA assays demonstrated, for the first time, a stretch-mediated suppression of sVEGFR-1 secretion 24 h after stretching. Overall, strained chondrocytes activate their VEGF expression, but in contrast, strain appears to suppress the secretion of the major VEGF decoy receptor (sVEGFR-1/sFlt-1. The latter may deplete a biologically relevant feedback regulation to inhibit destructive angiogenesis in articular cartilage. Our data suggest that mechanical stretch can induce morphological changes in human chondrocytes in vitro. More importantly, it induces disturbed VEGF signaling, providing a molecular mechanism for a stress-induced increase in angiogenesis in cartilage pathologies.

  2. Prolonged application of high fluid shear to chondrocytes recapitulates gene expression profiles associated with osteoarthritis.

    Directory of Open Access Journals (Sweden)

    Fei Zhu

    Full Text Available BACKGROUND: Excessive mechanical loading of articular cartilage producing hydrostatic stress, tensile strain and fluid flow leads to irreversible cartilage erosion and osteoarthritic (OA disease. Since application of high fluid shear to chondrocytes recapitulates some of the earmarks of OA, we aimed to screen the gene expression profiles of shear-activated chondrocytes and assess potential similarities with OA chondrocytes. METHODOLOGY/PRINCIPAL FINDINGS: Using a cDNA microarray technology, we screened the differentially-regulated genes in human T/C-28a2 chondrocytes subjected to high fluid shear (20 dyn/cm(2 for 48 h and 72 h relative to static controls. Confirmation of the expression patterns of select genes was obtained by qRT-PCR. Using significance analysis of microarrays with a 5% false discovery rate, 71 and 60 non-redundant transcripts were identified to be ≥2-fold up-regulated and ≤0.6-fold down-regulated, respectively, in sheared chondrocytes. Published data sets indicate that 42 of these genes, which are related to extracellular matrix/degradation, cell proliferation/differentiation, inflammation and cell survival/death, are differentially-regulated in OA chondrocytes. In view of the pivotal role of cyclooxygenase-2 (COX-2 in the pathogenesis and/or progression of OA in vivo and regulation of shear-induced inflammation and apoptosis in vitro, we identified a collection of genes that are either up- or down-regulated by shear-induced COX-2. COX-2 and L-prostaglandin D synthase (L-PGDS induce reactive oxygen species production, and negatively regulate genes of the histone and cell cycle families, which may play a critical role in chondrocyte death. CONCLUSIONS/SIGNIFICANCE: Prolonged application of high fluid shear stress to chondrocytes recapitulates gene expression profiles associated with osteoarthritis. Our data suggest a potential link between exposure of chondrocytes/cartilage to abnormal mechanical loading and the pathogenesis

  3. An experimental fatigue study of a porous scaffold for the regeneration of articular cartilage

    OpenAIRE

    VIKINGSSON, LINE KARINA ALVA; Gómez-Tejedor, José Antonio; Gallego Ferrer, Gloria; Gómez Ribelles, José Luís

    2015-01-01

    The aim of this experimental study is to predict the long-term mechanical behavior of a porous scaffold implanted in a cartilage defect for tissue engineering purpose. Fatigue studies were performed by up to 100,000 unconfined compression cycles in a polycaprolactone (PCL) scaffold with highly interconnected pores architecture. The scaffold compliance, stress strain response and hysteresis energy have been measured after different number of fatigue cycles, while the morphology has been observ...

  4. Modeling the Insulin-Like Growth Factor System in Articular Cartilage.

    Directory of Open Access Journals (Sweden)

    Lihai Zhang

    Full Text Available IGF signaling is involved in cell proliferation, differentiation and apoptosis in a wide range of tissues, both normal and diseased, and so IGF-IR has been the focus of intense interest as a promising drug target. In this computational study on cartilage, we focus on two questions: (i what are the key factors influencing IGF-IR complex formation, and (ii how might cells regulate IGF-IR complex formation? We develop a reaction-diffusion computational model of the IGF system involving twenty three parameters. A series of parametric and sensitivity studies are used to identify the key factors influencing IGF signaling. From the model we predict the free IGF and IGF-IR complex concentrations throughout the tissue. We estimate the degradation half-lives of free IGF-I and IGFBPs in normal cartilage to be 20 and 100 mins respectively, and conclude that regulation of the IGF half-life, either directly or indirectly via extracellular matrix IGF-BP protease concentrations, are two critical factors governing the IGF-IR complex formation in the cartilage. Further we find that cellular regulation of IGF-II production, the IGF-IIR concentration and its clearance rate, all significantly influence IGF signaling. It is likely that negative feedback processes via regulation of these factors tune IGF signaling within a tissue, which may help explain the recent failures of single target drug therapies aimed at modifying IGF signaling.

  5. Modeling the Insulin-Like Growth Factor System in Articular Cartilage

    Science.gov (United States)

    Zhang, Lihai; Smith, David W.; Gardiner, Bruce S.; Grodzinsky, Alan J.

    2013-01-01

    IGF signaling is involved in cell proliferation, differentiation and apoptosis in a wide range of tissues, both normal and diseased, and so IGF-IR has been the focus of intense interest as a promising drug target. In this computational study on cartilage, we focus on two questions: (i) what are the key factors influencing IGF-IR complex formation, and (ii) how might cells regulate IGF-IR complex formation? We develop a reaction-diffusion computational model of the IGF system involving twenty three parameters. A series of parametric and sensitivity studies are used to identify the key factors influencing IGF signaling. From the model we predict the free IGF and IGF-IR complex concentrations throughout the tissue. We estimate the degradation half-lives of free IGF-I and IGFBPs in normal cartilage to be 20 and 100 mins respectively, and conclude that regulation of the IGF half-life, either directly or indirectly via extracellular matrix IGF-BP protease concentrations, are two critical factors governing the IGF-IR complex formation in the cartilage. Further we find that cellular regulation of IGF-II production, the IGF-IIR concentration and its clearance rate, all significantly influence IGF signaling. It is likely that negative feedback processes via regulation of these factors tune IGF signaling within a tissue, which may help explain the recent failures of single target drug therapies aimed at modifying IGF signaling. PMID:23840540

  6. Chondroitin sulphate and heparan sulphate sulphation motifs and their proteoglycans are involved in articular cartilage formation during human foetal knee joint development.

    Science.gov (United States)

    Melrose, James; Isaacs, Marc D; Smith, Susan M; Hughes, Clare E; Little, Christopher B; Caterson, Bruce; Hayes, Anthony J

    2012-09-01

    Novel sulphation motifs within the glycosaminoglycan chain structure of chondroitin sulphate (CS) containing proteoglycans (PGs) are associated with sites of growth, differentiation and repair in many biological systems and there is compelling evidence that they function as molecular recognition sites that are involved in the binding, sequestration or presentation of soluble signalling molecules (e.g. morphogens, growth factors and cytokines). Here, using monoclonal antibodies 3B3(-), 4C3 and 7D4, we examine the distribution of native CS sulphation motifs within the developing connective tissues of the human foetal knee joint, both during and after joint cavitation. We show that the CS motifs have broad, overlapping distributions within the differentiating connective tissues before the joint has fully cavitated; however, after cavitation, they all localise very specifically to the presumptive articular cartilage tissue. Comparisons with the labelling patterns of heparan sulphate (HS), HS-PGs (perlecan, syndecan-4 and glypican-6) and FGF-2, molecules with known signalling roles in development, indicate that these also become localised to the future articular cartilage tissue after joint cavitation. Furthermore, they display interesting, overlapping distributions with the CS motifs, reflective of early tissue zonation. The overlapping expression patterns of these molecules at this site suggests they are involved, or co-participate, in early morphogenetic events underlying articular cartilage formation; thus having potential clinical relevance to mechanisms involved in its repair/regeneration. We propose that these CS sulphation motifs are involved in modulating the signalling gradients responsible for the cellular behaviours (proliferation, differentiation, matrix turnover) that shape the zonal tissue architecture present in mature articular cartilage. PMID:22617995

  7. Human platelet releasates combined with polyglycolic acid scaffold promote chondrocyte differentiation and phenotypic maintenance

    Indian Academy of Sciences (India)

    Giulia Bernardini; Federico Chellini; Bruno Frediani; Adriano Spreafico; Annalisa Santucci

    2015-03-01

    In the present study, we aimed to demonstrate the differentiating properties of platelet-rich plasma releasates (PRPr) on human chondrocytes seeded on a polygtlycolic acid (PGA) 3D scaffold. Gene expression and biochemical analysis were carried out to assess the improved quality of our PGA-based cartilage constructs supplemented with PRPr. We observed that the use of PRPr as cell cultures supplementation to PGA-chondrocyte constructs may promote chondrocyte differentiation, and thus may contribute to maintaining the chondrogenic phenotype longer than conventional supplementation by increasing high levels of important chondrogenic markers (e.g. sox9, aggrecan and type II collagen), without induction of type I collagen. Moreover, our constructs were analysed for the secretion and deposition of important ECM molecules (sGAG, type II collagen, etc.). Our results indicate that PRPr supplementation may synergize with PGA-based scaffolds to stimulate human articular chondrocyte differentiation, maturation and phenotypic maintenance.

  8. Increased adipogenesis in cultured embryonic chondrocytes and in adult bone marrow of dominant negative Erg transgenic mice.

    Directory of Open Access Journals (Sweden)

    Sébastien Flajollet

    Full Text Available In monolayer culture, primary articular chondrocytes have an intrinsic tendency to lose their phenotype during expansion. The molecular events underlying this chondrocyte dedifferentiation are still largely unknown. Several transcription factors are important for chondrocyte differentiation. The Ets transcription factor family may be involved in skeletal development. One family member, the Erg gene, is mainly expressed during cartilage formation. To further investigate the potential role of Erg in the maintenance of the chondrocyte phenotype, we isolated and cultured chondrocytes from the rib cartilage of embryos of transgenic mice that express a dominant negative form of Erg (DN-Erg during cartilage formation. DN-Erg expression in chondrocytes cultured for up to 20 days did not affect the early dedifferentiation usually observed in cultured chondrocytes. However, lipid droplets accumulated in DN-Erg chondrocytes, suggesting adipocyte emergence. Transcriptomic analysis using a DNA microarray, validated by quantitative RT-PCR, revealed strong differential gene expression, with a decrease in chondrogenesis-related markers and an increase in adipogenesis-related gene expression in cultured DN-Erg chondrocytes. These results indicate that Erg is involved in either maintaining the chondrogenic phenotype in vitro or in cell fate orientation. Along with the in vitro studies, we compared adipocyte presence in wild-type and transgenic mice skeletons. Histological investigations revealed an increase in the number of adipocytes in the bone marrow of adult DN-Erg mice even though no adipocytes were detected in embryonic cartilage or bone. These findings suggest that the Ets transcription factor family may contribute to the homeostatic balance in skeleton cell plasticity.

  9. The pro-inflammatory cytokine 14-3-3ε is a ligand of CD13 in cartilage.

    Science.gov (United States)

    Nefla, Meriam; Sudre, Laure; Denat, Guillaume; Priam, Sabrina; Andre-Leroux, Gwenaëlle; Berenbaum, Francis; Jacques, Claire

    2015-09-01

    Osteoarthritis is a whole-joint disease characterized by the progressive destruction of articular cartilage involving abnormal communication between subchondral bone and cartilage. Our team previously identified 14-3-3ε protein as a subchondral bone soluble mediator altering cartilage homeostasis. The aim of this study was to investigate the involvement of CD13 (also known as aminopeptidase N, APN) in the chondrocyte response to 14-3-3ε. After identifying CD13 in chondrocytes, we knocked down CD13 with small interfering RNA (siRNA) and blocking antibodies in articular chondrocytes. 14-3-3ε-induced MMP-3 and MMP-13 was significantly reduced with CD13 knockdown, which suggests that it has a crucial role in 14-3-3ε signal transduction. Aminopeptidase N activity was identified in chondrocytes, but the activity was unchanged after stimulation with 14-3-3ε. Direct interaction between CD13 and 14-3-3ε was then demonstrated by surface plasmon resonance. Using labeled 14-3-3ε, we also found that 14-3-3ε binds to the surface of chondrocytes in a manner that is dependent on CD13. Taken together, these results suggest that 14-3-3ε might directly bind to CD13, which transmits its signal in chondrocytes to induce a catabolic phenotype similar to that observed in osteoarthritis. The 14-3-3ε-CD13 interaction could be a new therapeutic target in osteoarthritis. PMID:26208633

  10. The pro-inflammatory cytokine 14-3-3ε is a ligand of CD13 in cartilage

    Science.gov (United States)

    Nefla, Meriam; Sudre, Laure; Denat, Guillaume; Priam, Sabrina; Andre-Leroux, Gwenaëlle; Berenbaum, Francis; Jacques, Claire

    2015-01-01

    ABSTRACT Osteoarthritis is a whole-joint disease characterized by the progressive destruction of articular cartilage involving abnormal communication between subchondral bone and cartilage. Our team previously identified 14-3-3ε protein as a subchondral bone soluble mediator altering cartilage homeostasis. The aim of this study was to investigate the involvement of CD13 (also known as aminopeptidase N, APN) in the chondrocyte response to 14-3-3ε. After identifying CD13 in chondrocytes, we knocked down CD13 with small interfering RNA (siRNA) and blocking antibodies in articular chondrocytes. 14-3-3ε-induced MMP-3 and MMP-13 was significantly reduced with CD13 knockdown, which suggests that it has a crucial role in 14-3-3ε signal transduction. Aminopeptidase N activity was identified in chondrocytes, but the activity was unchanged after stimulation with 14-3-3ε. Direct interaction between CD13 and 14-3-3ε was then demonstrated by surface plasmon resonance. Using labeled 14-3-3ε, we also found that 14-3-3ε binds to the surface of chondrocytes in a manner that is dependent on CD13. Taken together, these results suggest that 14-3-3ε might directly bind to CD13, which transmits its signal in chondrocytes to induce a catabolic phenotype similar to that observed in osteoarthritis. The 14-3-3ε–CD13 interaction could be a new therapeutic target in osteoarthritis. PMID:26208633

  11. Evaluation of the repair of full-thickness articular cartilage defects filled with autologous exogenous fibrin clot: An experimental study in the shoulder joint of dogs

    Directory of Open Access Journals (Sweden)

    Avki S.

    2003-01-01

    Full Text Available To determine whether the optimizing effect of an exogenous fibrin clot in the repair of full–thickness articular cartilage defects is valid when joint motions are restricted, standard osteochondral defects were constituted in the articular surface of the humeral head in 16 adult dogs. The defects in 8 dogs were packed with fibrin clots that had been prepared exogenously from each animal and the defects of the other animals were left empty. The operated limbs were inactivated for 2 weeks postoperatively and the healing response was then examined using routine histology at 2, 4, 8 and 12-week intervals. Although the clot-filled and control (empty defects initially healed through proliferation of fibrous connective tissue; the clot-filled defects finally modulated into fibrocartilage with completed subchondral bone formation. The clot-filled defects demonstrated a more advanced reparative tissue which was congruent with the intact articular surface from 4 weeks after the intervention.

  12. Millicurrent stimulation of human articular chondrocytes cultivated in a collagen type-I gel and of human osteochondral explants

    Directory of Open Access Journals (Sweden)

    Silny Jiri

    2010-08-01

    Full Text Available Abstract Background Here we investigate the effect of millicurrent treatment on human chondrocytes cultivated in a collagen gel matrix and on human osteochondral explants. Methods Human chondrocytes from osteoarthritic knee joints were enzymatically released and transferred into a collagen type-I gel. Osteochondral explants and cell-seeded gel samples were cultivated in-vitro for three weeks. Samples of the verum groups were stimulated every two days by millicurrent treatment (3 mA, sinusoidal signal of 312 Hz amplitude modulated by two super-imposed signals of 0.28 Hz, while control samples remained unaffected. After recovery, collagen type-I, type-II, aggrecan, interleukin-1β, IL-6, TNFα and MMP13 were examined by immunohistochemistry and by real time PCR. Results With regard to the immunostainings 3 D gel samples and osteochondral explants did not show any differences between treatment and control group. The expression of all investigated genes of the 3 D gel samples was elevated following millicurrent treatment. While osteochondral explant gene expression of col-I, col-II and Il-1β was nearly unaffected, aggrecan gene expression was elevated. Following millicurrent treatment, IL-6, TNFα, and MMP13 gene expression decreased. In general, the standard deviations of the gene expression data were high, resulting in rarely significant results. Conclusions We conclude that millicurrent stimulation of human osteoarthritic chondrocytes cultivated in a 3 D collagen gel and of osteochondral explants directly influences cell metabolism.

  13. Enhanced cleavage of type II collagen by collagenases in osteoarthritic articular cartilage.

    OpenAIRE

    Billinghurst, R.C.; Dahlberg, L; Ionescu, M.; Reiner, A; Bourne, R; Rorabeck, C; Mitchell, P; Hambor, J; Diekmann, O.; Tschesche, H; Chen, J; Van Wart, H; Poole, A. R.

    1997-01-01

    We demonstrate the direct involvement of increased collagenase activity in the cleavage of type II collagen in osteoarthritic human femoral condylar cartilage by developing and using antibodies reactive to carboxy-terminal (COL2-3/4C(short)) and amino-terminal (COL2-1/4N1) neoepitopes generated by cleavage of native human type II collagen by collagenase matrix metalloproteinase (MMP)-1 (collagenase-1), MMP-8 (collagenase-2), and MMP-13 (collagenase-3). A secondary cleavage followed the initia...

  14. ERK activation is required for hydrostatic pressure induced-tensile changes in engineered articular cartilage

    OpenAIRE

    DuRaine, G D; Athanasiou, K.A.

    2012-01-01

    The objective of this study was to identify the ERK 1/2 involvement in the changes in compressive and tensile mechanical properties associated with hydrostatic pressure treatment of self-assembled cartilage constructs. In study 1, ERK 1/2 phosphorylation was detected by immunoblot following application of hydrostatic pressure (1 hour of static 10MPa) applied at day 10-14 of self-assembly culture. In study 2, ERK 1/2 activation was blocked during hydrostatic pressure application on days 10-14....

  15. Articular cartilage defect detectability in human knees with MR-arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Engel, A. [Orthopaedic Clinic, Univ. of Vienna (Austria); Kramer, J. [MR-Inst., Univ. of Vienna (Austria); Stiglbauer, R. [MR-Inst., Univ. of Vienna (Austria); Hajek, P.C. [MR-Inst., Univ. of Vienna (Austria); Imhof, H. [MR-Inst., Univ. of Vienna (Austria)

    1993-04-01

    One hundred and thirteen knee joints were examined, of which 48 showed damage of the hyaline cartilage in one or more locations. For the evaluation of the magnetic resonance (MR) arthrographic images we used the macroscopic staging according to Outerbridge, the defect staging according to Bauer, as well as a new MR-arthrographic staging. The results of the evaluation were compared with the surgical findings in 61 knee joints. This revealed a sensitivity of 86 %, a specificity of 100 % and accuracy of 90 %. All lesions that could not be classified on MR-arthrography were of stage-I chondromalacia. (orig.)

  16. Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation

    DEFF Research Database (Denmark)

    Sondergaard, B C; Henriksen, K; Wulf, H;

    2006-01-01

    explants were stimulated with oncostatin M (OSM) 10 ng/ml and tumor necrosis factor-alpha (TNF-alpha) 20 ng/ml in the presence or absence of the broad-spectrum MMP inhibitor GM6001 and the cysteine protease inhibitor, E64. Cartilage degradation was evaluated in the conditioned medium by glycosaminoglycans...... vivo in CK null mice. CONCLUSION: Inhibition of MMP activity reduced both proteoglycan loss and type II collagen degradation. In contrast, inhibition of cysteine proteases resulted in an increase rather than a decrease in MMP derived fragments of collagen type II degradation, CTX-II, suggesting altered...

  17. Fisiopatología celular de la osteoartritis: el condrocito articular como protagonista = Osteoarthritis cellular pathophysiology: The articular chondrocyte as a central player

    OpenAIRE

    Sánchez Naranjo, Julio César; López Zapata, Diego Fernando

    2011-01-01

    La osteoartritis es una de las enfermedades más prevalentes y que más discapacidad produce en todo el mundo, lo que ocasiona costos altos para el paciente y la sociedad. En años recientes se ha venido obteniendo información importante sobre el funcionamiento normal del condrocito, la única célula presente en el cartílago articular y responsable de la síntesis de matriz extracelular. El condrocito responde a las condiciones fluctuantes del medio, generadas por los cambios de presión, modifican...

  18. An in vitro comparative study of T2 and T2* mappings of human articular cartilage at 3-Tesla MRI using histology as the standard of reference

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Taehee; Park, Sunghoon [Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Ajou University Medical Center, Musculoskeletal Imaging Laboratory, Suwon (Korea, Republic of); Min, Byoung-Hyun [Ajou University School of Medicine, Department of Orthopaedic Surgery, Suwon (Korea, Republic of); Ajou University School of Medicine, Cartilage Regeneration Center, Suwon (Korea, Republic of); Yoon, Seung-Hyun [Ajou University School of Medicine, Cartilage Regeneration Center, Suwon (Korea, Republic of); Kim, Hakil [INHA University, School of Information and Communication Engineering, Incheon (Korea, Republic of); Lee, Hyun Young [Ajou University Medical Center, Regional Clinical Trial Center, Suwon (Korea, Republic of); Yonsei University College of Medicine, Department of Biostatistics, Seoul (Korea, Republic of); Kwack, Kyu-Sung [Ajou University School of Medicine, Department of Radiology, Suwon (Korea, Republic of); Ajou University Medical Center, Musculoskeletal Imaging Laboratory, Suwon (Korea, Republic of); Ajou University School of Medicine, Cartilage Regeneration Center, Suwon (Korea, Republic of)

    2014-07-15

    The aim of this study was to evaluate the correlations between T2 value, T2* value, and histological grades of degenerated human articular cartilage. T2 mapping and T2* mapping of nine tibial osteochondral specimens were obtained using a 3-T MRI after total knee arthroplasty. A total of 94 ROIs were analyzed. Histological grades were assessed using the David-Vaudey scale. Spearman's rho correlation analysis and Pearson's correlation analysis were performed. The mean relaxation values in T2 map with different histological grades (0, 1, 2) of the cartilage were 51.9 ± 9.2 ms, 55.8 ± 12.8 ms, and 59.6 ± 10.2 ms, respectively. The mean relaxation values in T2* map with different histological grades (0, 1, 2) of the cartilage were 20.3 ± 10.3 ms, 21.1 ± 12.4 ms, and 15.4 ± 8.5 ms, respectively. Spearman's rho correlation analysis confirmed a positive correlation between T2 value and histological grade (ρ = 0.313, p < 0.05). Pearson's correlation analysis revealed a significant negative correlation between T2 and T2* (r = -0.322, p < 0.05). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, this correlation was not statistically significant in this study (ρ = -0.192, p = 0.129). T2 mapping was correlated with histological degeneration, and it may be a good biomarker for osteoarthritis in human articular cartilage. However, the strength of the correlation was weak (ρ = 0.313). Although T2* values showed a decreasing trend with an increase in cartilage degeneration, the correlation was not statistically significant. Therefore, T2 mapping may be more appropriate for the initial diagnosis of articular cartilage degeneration in the knee joint. Further studies on T2* mapping are needed to confirm its reliability and mechanism in cartilage degeneration. (orig.)

  19. Demonstration of the therapeutic effect of /sup 35/S labelled L-cystine in articular and intervertebral cartilage as well as in skeletal musculature

    Energy Technology Data Exchange (ETDEWEB)

    Schmiegelow, P.; Puschmann, M.; Giese, U.

    1984-01-16

    Clinical experience has obviously shown a positive effect of application of sulfated amino acids on degenerative cartilage diseases. L-Cystin, presumed to be of therapeutic effect, was autoradiographically localized in articular, columnar and intervertebral cartilage as well as in skeletal musculature. In 10 days old NMRI-mice, we had shown a dose-dependent incorporation of the radioactively labelled /sup 35/S-Cystin in hair follicle. These statistically significant differences had been measured by quantitative autoradiographical microscope photometry. The sulfated amino acids are also proven in nail matrix, nail hyponychium as well as in cartilage and skeletal musculature. Besides a localization of radioactively labelled L-Cystin in tissues, presumed as target organs of a therapeutic effect, there is still lacking an experimental proof of efficacy on cell proliferation and functional metabolism e.g. in arthrosis by suitable animal models.

  20. Demonstration of the therapeutic effect of 35S labelled L-cystine in articular and intervertebral cartilage as well as in skeletal musculature

    International Nuclear Information System (INIS)

    Clinical experience has obviously shown a positive effect of application of sulfated amino acids on degenerative cartilage diseases. L-Cystin, presumed to be of therapeutic effect, was autoradiographically localized in articular, columnar and intervertebral cartilage as well as in skeletal musculature. In 10 days old NMRI-mice, we had shown a dose-dependent incorporation of the radioactively labelled 35S-Cystin in hair follicle. These statistically significant differences had been measured by quantitative autoradiographical microscope photometry. The sulfated amino acids are also proven in nail matrix, nail hyponychium as well as in cartilage and skeletal musculature. Besides a localization of radioactively labelled L-Cystin in tissues, presumed as target organs of a therapeutic effect, there is still lacking an experimental proof of efficacy on cell proliferation and functional metabolism e.g. in arthrosis by suitable animal models. (orig.)

  1. Prostaglandin E2 regulates the expression of connective tissue growth factor (CTGF/CCN2 in human osteoarthritic chondrocytes via the EP4 receptor

    Directory of Open Access Journals (Sweden)

    Nakamura Hiroshi

    2010-01-01

    Full Text Available Abstract Background The regulatory mechanisms of the expression of connective tissue growth factor/CCN family member 2 (CTGF/CCN2 in human articular chondrocytes have not been clarified. We investigated the effect of prostaglandin E2 (PGE2 on CTGF/CCN2 expression in chondrocytes. Findings Articular cartilage samples were obtained from patients with osteoarthritis (OA and chondrocytes were isolated and cultured in vitro. Chondrocytes were stimulated with PGE2, PGE receptor (EP-specific agonists, or interleukin (IL-1. CTGF expression was analyzed using quantitative polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay. The inhibitory effects of EP receptor antagonists (for EP2 and EP4 against PGE2 stimulation were also investigated. Stimulation of chondrocytes with PGE2 or IL-1 significantly suppressed CTGF expression. The suppressive effect of PGE2 was reproduced by EP2/EP4 receptor agonists but not by EP1/EP3 receptor agonists, and was partially blocked by an EP4 receptor antagonist, suggesting that the EP4 receptor has a dominant role. Conclusions PGE2 may be involved in the regulation of CTGF/CCN2 expression in human articular chondrocytes via the EP4 receptor. Elucidation of EP4-mediated signaling in chondrocytes may contribute to a better understanding of the effects of PGE2 in arthritis.

  2. Finite Element Analysis Of Large Deformation Of Articular Cartilage In Upper Ankle Joint Of Occupant In Military Vehicles During Explosion

    Directory of Open Access Journals (Sweden)

    Klekiel T.

    2015-09-01

    Full Text Available The paper presents the analysis of the load of lower limbs of occupants in the armoured military vehicle, which has been destroyed by detonation of the Improvised Explosive Device (IED charge under the vehicle. A simplified model of the human lower limb focused on upper ankle joint was developed in order to determine the reaction forces in joints and load in particular segments during the blast load. The model of upper ankle joint, include a tibia and an ankle bone with corresponding articular cartilage, has been developed. An analysis of the stress distribution under the influence of forces applied at different angles to the biomechanical axis of a limb has been performed. We analyzed the case of the lower limb of a sitting man leaning his feet on the floor. It has been shown that during a foot pronation induced by a knee outward deviation, the axial load on the foot causes significantly greater tension in the tibia. At the same time it has been shown that within the medial malleolus, tensile stresses occur on the surface of the bone which may lead to fracture of the medial malleolus. It is a common case of injuries caused by loads on foot of passengers in armored vehicles during a mine or IED load under the vehicle. It was shown that the outward deviation of the knee increases the risk of the foot injury within the ankle joint.

  3. Downregulation of protein kinase CK2 activity facilitates tumor necrosis factor-α-mediated chondrocyte death through apoptosis and autophagy.

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    Sung Won Lee

    Full Text Available Despite the numerous studies of protein kinase CK2, little progress has been made in understanding its function in chondrocyte death. Our previous study first demonstrated that CK2 is involved in apoptosis of rat articular chondrocytes. Recent studies have suggested that CK2 downregulation is associated with aging. Thus examining the involvement of CK2 downregulation in chondrocyte death is an urgently required task. We undertook this study to examine whether CK2 downregulation modulates chondrocyte death. We first measured CK2 activity in articular chondrocytes of 6-, 21- and 30-month-old rats. Noticeably, CK2 activity was downregulated in chondrocytes with advancing age. To build an in vitro experimental system for simulating tumor necrosis factor (TNF-α-induced cell death in aged chondrocytes with decreased CK2 activity, chondrocytes were co-treated with CK2 inhibitors and TNF-α. Viability assay demonstrated that CK2 inhibitors facilitated TNF-α-mediated chondrocyte death. Pulsed-field gel electrophoresis, nuclear staining, flow cytometry, TUNEL staining, confocal microscopy, western blot and transmission electron microscopy were conducted to assess cell death modes. The results of multiple assays showed that this cell death was mediated by apoptosis. Importantly, autophagy was also involved in this process, as supported by the appearance of a punctuate LC3 pattern and autophagic vacuoles. The inhibition of autophagy by silencing of autophage-related genes 5 and 7 as well as by 3-methyladenine treatment protected chondrocytes against cell death and caspase activation, indicating that autophagy led to the induction of apoptosis. Autophagic cells were observed in cartilage obtained from osteoarthritis (OA model rats and human OA patients. Our findings indicate that CK2 down regulation facilitates TNF-α-mediated chondrocyte death through apoptosis and autophagy. It should be clarified in the future if autophagy observed is a consequence

  4. Advances in understanding cartilage remodeling [v1; ref status: indexed, http://f1000r.es/5e6

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    Yefu Li

    2015-08-01

    Full Text Available Cartilage remodeling is currently among the most popular topics in osteoarthritis research. Remodeling includes removal of the existing cartilage and replacement by neo-cartilage. As a loss of balance between removal and replacement of articular cartilage develops (particularly, the rate of removal surpasses the rate of replacement, joints will begin to degrade. In the last few years, significant progress in molecular understanding of the cartilage remodeling process has been made. In this brief review, we focus on the discussion of some current “controversial” observations in articular cartilage degeneration: (1 the biological effect of transforming growth factor-beta 1 on developing and mature articular cartilages, (2 the question of whether aggrecanase 1 (ADAMTS4 and aggrecanase 2 (ADAMTS5 are key enzymes in articular cartilage destruction, and (3 chondrocytes versus chondron in the development of osteoarthritis. It is hoped that continued discussion and investigation will follow to better clarify these topics. Clarification will be critical for those in search of novel therapeutic targets for the treatment of osteoarthritis.

  5. Changes in the Loading of Tibial Articular Cartilage Following Varus and Valgus Mechanical Axis of Lower Extremity: A Finite Element Model Study

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    Halil Atmaca

    2014-06-01

    Full Text Available Objective: To evaluate changes in the loading of tibial articular cartilage following varus and valgus mechanical axis of lower extremity. Methods: Three- Dimensional (3D solid models were created on MIMICS ® by using DICOM formatted longitudinal computed tomography scans. Respectively 2.5°, 5°, 7.5°, 10°, 12.5° and 15° varus and valgus osteotomies were performed to 3D solid models. ANSYS ® WorkbenchTM (Version 12 was used to analyze the stress/load distribution, that is to say MES (maximum equivalent stress- von Mises stres, which affect the tibia cartilage in the finite element model obtained by MIMICS ® . Results: MES of the tibial cartilage was measured 0.860 MPa in the reference model. With regard to the varus models, MES was measured 0.935 MPa in 2.5° varus model, 1.010 MPa in 5°, 1.113 MPa in 7.5°, 1.247 MPa in 10°, 1.388 MPa in 12.5° and 1.530 MPa in 15° varus model. MES was measured 0.813, 0.792, 0.769, 0.745, 0.718 and 0.690 MPa in 2.5°, 5°, 7.5°, 10°, 12.5° and 15° valgus osteotomy models respectively (p=0.028. Conclusion: MES increased in all models of varus position when was compared with reference and valgus models. The decrease of load bearing on tibial articular cartilage in valgus position was lower and statistically different than the reference and varus models. This study clearly showed that tibia cartilage is more sensitive to load bearing in varus position than the valgus positioned lower extremity mechanical axis.

  6. An experimental fatigue study of a porous scaffold for the regeneration of articular cartilage.

    Science.gov (United States)

    Vikingsson, L; Gómez-Tejedor, J A; Gallego Ferrer, G; Gómez Ribelles, J L

    2015-05-01

    The aim of this experimental study is to predict the long-term mechanical behavior of a porous scaffold implanted in a cartilage defect for tissue engineering purpose. Fatigue studies were performed by up to 100,000 unconfined compression cycles in a polycaprolactone (PCL) scaffold with highly interconnected pores architecture. The scaffold compliance, stress-strain response and hysteresis energy have been measured after different number of fatigue cycles, while the morphology has been observed by scanning electron microscopy at the same fatigue times. To simulate the growing tissue in the scaffold/tissue construct, the scaffold was filled with an aqueous solution of polyvinyl alcohol (PVA) and subjected to repeating cycles of freezing and thawing that increase the hydrogel stiffness. Fatigue studies show that the mechanical loading provokes failure of the dry scaffold at a smaller number of deformation cycles than when it is immersed in water, and also that 100,000 compressive dynamic cycles do not affect the scaffold/gel construct. This shows the stability of the scaffold implanted in a chondral defect and gives a realistic simulation of the mechanical performance from implantation of the empty scaffold to regeneration of the new tissue inside the scaffold's pores. PMID:25814177

  7. Evaluation of Labral Pathology and Hip Articular Cartilage in Patients with Femoroacetabular Impingement (FAI): Comparison of Multidetector CT Arthrography and MR Arthrography

    International Nuclear Information System (INIS)

    To compare the multidetector computed tomography (MDCT) arthrography (CTa) and magnetic resonance (MR) arthrography (MRa) findings with surgical findings in patients with femoroacetabular impingement (FAI) and to evaluate the diagnostic performance of these methods. Labral pathology and articular cartilage were prospectively evaluated with MRa and CTa in 14 hips of 14 patients. The findings were evaluated by two musculoskeletal radiologists with 10 and 20 years of experience, respectively. Sensitivity, specificity, accuracy, and positive predictive value were determined using surgical findings as the standard of reference. While the disagreement between observers was recorded in two cases of labral tearing with MRa, there was a complete consensus with CTa. Disagreement between observers was found in four cases of femoral cartilage loss with both MRa and CTa. Disagreement was also recorded in only one case of acetabular cartilage loss with both methods. The percent sensitivity, specificity, and accuracy for correctly assessing the labral tearing were as follows for MRa/CTa, respectively: 100/100, 50/100, 86/100 (p<0.05). The same values for acetabular cartilage assessment were 89/56, 40/60, 71/71 (p>0.05) and for femoral cartilage assessment were 100/75, 90/70, 86/71 (p>0.05). Inter-observer reliability value showed excellent agreement for labral tearing with CTa (κ=1.0). Inter-observer agreement was substantial to excellent with regard to acetabular cartilage assessment with MRa and CTa (κ=0.76 for MRa and κ=0.86 for CTa) Inter-observer reliability with CTa is excellent for labral tearing assessment. CTa seems to have an equal sensitivity and a higher specificity than MRa for the detection of labral pathology. MRa is better, but not statistically significantly, in demonstrating acetabular and femoral cartilage pathology

  8. Fisiopatología celular de la osteoartritis: el condrocito articular como protagonista = Osteoarthritis cellular pathophysiology: The articular chondrocyte as a central player

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    Sánchez Naranjo, Julio César

    2011-06-01

    Full Text Available La osteoartritis es una de las enfermedades más prevalentes y que más discapacidad produce en todo el mundo, lo que ocasiona costos altos para el paciente y la sociedad. En años recientes se ha venido obteniendo información importante sobre el funcionamiento normal del condrocito, la única célula presente en el cartílago articular y responsable de la síntesis de matriz extracelular. El condrocito responde a las condiciones fluctuantes del medio, generadas por los cambios de presión, modificando su composición iónica y alterando el transporte de solutos y agua en su membrana. Esta capacidad de respuesta es clave para el mantenimiento de la matriz extracelular y, por ende, de un cartílago funcional. Diversos factores relacionados con enfermedades crónicas metabólicas inician una cascada de eventos que termina con una respuesta inadecuada del condrocito ante la carga mecánica, lo cual lleva a un predominio del catabolismo de la matriz y a un cartílago defectuoso que es la base del desarrollo de la osteoartritis. En este proceso están implicadas diversas citocinas y hormonas que afectan la homeostasis del cartílago y que pueden constituirse en blancos terapéuticos prometedores.

  9. The value of water-excitation 3D FLASH and fat-saturated PDw TSE MR imaging for detecting and grading articular cartilage lesions of the knee

    International Nuclear Information System (INIS)

    To evaluate the diagnostic accuracy of water-excitation (WE) 3D FLASH and fat-saturated (FS) proton density-weighted (PDw) TSE MR imaging for detecting, grading, and sizing articular cartilage lesions of the knee. A total of 26 patients underwent MR imaging prior to arthroscopy with the following sequences: (1) WE 3D FLASH: 28/11 ms, scan time: 4 min 58 s, flip angle: 40 ; (2) FS PDw TSE: 3433/15 ms, scan time: 6 min 15 s, flip angle: 180 . Grade and size of the detected lesions were quantified and compared with the results of arthroscopy for each compartment. The sensitivity, specificity, positive and negative predictive values, and accuracy for detecting cartilage lesions were 46%, 92%, 81%, 71% and 74% for WE 3D FLASH and 91%, 98%, 96%, 94% and 95% for FS PDw TSE MR imaging. WE 3D FLASH correlated significantly with arthroscopy for grading on the patella (P<0.0001) and the femoral trochlea (P=0.02) and for sizing on the femoral trochlea (P=0.03). FS PDw correlated significantly (P<0.0001) with arthroscopy for grading and sizing on all compartments. FS PDw TSE is an accurate method for detecting, grading and sizing articular cartilage lesions of the knee and yielded superior results relative to WE 3D FLASH MR imaging. (orig.)

  10. Stability of housekeeping genes in human intervertebral disc, endplate and articular cartilage cells in multiple conditions for reliable transcriptional analysis.

    Science.gov (United States)

    Lopa, S; Ceriani, C; Cecchinato, R; Zagra, L; Moretti, M; Colombini, A

    2016-01-01

    Quantitative gene expression analysis is widely used to evaluate the expression of specific tissue markers. To obtain reliable data it is essential to select stable housekeeping genes whose expression is not influenced by the anatomical origin of cells or by the culture conditions. No studies have evaluated housekeeping gene stability in intervertebral disc (IVD) cells and only few studies using cartilaginous endplate (CEP) and articular cartilage (AC) cells are present in the literature. We analysed the stability of four candidate housekeeping genes (GAPDH, TBP, YWHAZ and RPL13A) in human cells isolated from nucleus pulposus (NP) and annulus fibrosus (AF), CEP and AC. Cell isolation, expansion, cryoconservation, and differentiation in 3D pellets were tested. GeNorm, NormFinder, BestKeeper tools and the comparative ΔCt method were used to evaluate housekeeping gene stability. In each cell population, TBP alone or combined with YWHAZ was identified as the best normaliser in both monolayer and 3D pellets. GAPDH was the best performer only for AC cells in monolayer. In most culture conditions considering groups of two or more cell types, TBP was the most stable and YWHAZ was the second choice. GAPDH was the best performer only in 3D pellets with factors for AC and AF combined with CEP cells. RPL13A was the most stable only for AF with CEP cells at isolation. Our findings will be useful to properly design the experimental set-up of studies involving IVD, CEP or AC cells in different culture conditions, in order to obtain accurate and high quality data from quantitative gene expression analysis. PMID:27232666

  11. Saponin-rich fraction from Clematis chinensis Osbeck roots protects rabbit chondrocytes against nitric oxide-induced apoptosis via preventing mitochondria impairment and caspase-3 activation.

    Science.gov (United States)

    Wu, Wenjun; Gao, Xinghua; Xu, Xianxiang; Luo, Yubin; Liu, Mei; Xia, Yufeng; Dai, Yue

    2013-03-01

    Our previous study reported that the saponin-rich fraction from Clematis chinensis Osbeck roots (SFC) could effectively alleviate experimental osteoarthritis induced by monosodium iodoacetate in rats through protecting articular cartilage and inhibiting local inflammation. The present study was performed to investigate the preventive effects of SFC on articular chondrocyte, and explore the underlying mechanisms. Primary rabbit chondrocytes were cultured and exposed to sodium nitroprusside (SNP), a NO donor. After treatment with different concentrations of SFC (30, 100, 300, 1,000 μg/ml) for 24 h, nucleic morphology, apoptotic rate, mitochondrial function and caspase-3 activity of chondrocytes were examined. The results showed that SNP induced remarkable apoptosis of rabbit chondrocytes evidenced by Hoechst 33258 staining and flow cytometry analysis, and SFC prevented the apoptosis in a concentration-dependent manner. Further studies indicated that SFC could prevent the depolarization of mitochondrial membrane potential (∆ψm) in SNP-treated chondrocytes and suppress the activation of caspase-3. It can be concluded that the protection of SFC on articular chondrocytes is associated with the anti-apoptosis effects via inhibiting the mitochondrion impairment and caspase-3 activation. PMID:22821055

  12. The 3-D collagen structure of equine articular cartilage, characterized using variable-angle-of-incidence polarization-sensitive optical coherence tomography

    Science.gov (United States)

    Ugryumova, Nadya; Gangnus, Sergei V.; Matcher, Stephen J.

    2005-08-01

    Polarization-sensitive optical coherence tomography has been used to spatially map the birefringence of equine articular cartilage. Images obtained in the vicinity of visible osteoarthritic lesions display a characteristic disruption of the regular birefringence bands shown by normal cartilage. We also note that significant (e.g. ×2) variations in the apparent birefringence of samples taken from young (18 month) animals that otherwise appear visually homogeneous are found over spatial scales of a few millimeters. We suggest that whilst some of this variation may be due to changes in the intrinsic birefringence of the tissue, the 3-D orientation of the collagen fibers relative to the plane of the joint surface should also be taken into account. We propose a method based on multiple angles of illumination to determine the polar angle of the collagen fibers.

  13. Variable angle-of-incidence polarization-sensitive optical coherence tomography: its use to study the 3D collagen structure of equine articular cartilage

    Science.gov (United States)

    Ugryumova, Nadya; Gangnus, Sergei V.; Matcher, Stephen J.

    2006-02-01

    Polarization-sensitive optical coherence tomography has been used to spatially map the birefringence of equine articular cartilage. The polar orientation of the collagen fibers relative to the plane of the joint surface must be taken into account if a quantitative measurement of true birefringence is required. Using a series of images taken at different angles of illumination, we determine the fiber polar angle and true birefringence at one site on a sample of equine cartilage, on the assumption that the fibers lie within the plane of imaging. We propose a more general method based on the extended Jones matrix formalism to determine both the polar and azimuthal orientation of the collagen fibers as well as the true birefringence as functions of depth.

  14. Knee-joint articular cartilage demonstrated by magnetic resonance tomography. MR chondrovolumetry using a fat-suppressed FLASH-3D sequence

    International Nuclear Information System (INIS)

    A fat-suppressed FLASH-3D sequence was optimized on healthy volunteers. A fresh cardaveric knee joint was removed from a 82-year-old man and immediately imaged without being frozen or fixed. MRT was carried out at 1.5 T and 25 mT/m (Vision, Siemens, Erlangen, Germany) with a conventional CP knee coil. Sagittal and transverse sections were acquired perpendicular to the articular surfaces, and then, parallel to these imaging planes, anatomical sections were obtained with a diamond band saw. The volumes of the patellar, tibial and femoral cartilages were determined from both the images and the sections, using an image analysing system. Signal intensities and contrast-to-noise ratios depend on the parameters used. The highest contrast between the cartilage and the periarticular tissues was obtained at a flip angel of 30 (TR=60 ms, TE=11 ms). However, a flip angle of 60 was judged to provide optimal subjective image quality. Using these parameters, the deviations between the radiological and the anatomical cartilage volumes were -4.7% in the patella, -3.1% in the tibial plateau and -4.2% in the femur. The volumes of the knee-joint cartilages may be accurately determined with MRT if an appropriate pulse sequence is chosen. (orig./VHE)

  15. The search for negative amplitude components in quasi-continuous distributions of relaxation times: the example of 1H magnetization exchange in articular cartilage and hydrated collagen

    International Nuclear Information System (INIS)

    When inverting nuclear magnetic resonance relaxation data in order to obtain quasi-continuous distributions of relaxation times for fluids in porous media, it is common practice to impose a non-negative (NN) constraint on the distributions. While this approach can be useful in reducing the effects of data distortion and/or preventing wild oscillations in the distributions, it may give misleading results in the presence of real negative amplitude components. Here, some examples of valid negative components for articular cartilage and hydrated collagen are given. Articular cartilage is a connective tissue, consisting mainly of collagen, proteoglycans and water, which can be considered, in many aspects, as a porous medium. Separate T1 relaxation data are obtained for low-mobility ('solid') macromolecular 1H and for higher-mobility ('liquid') 1H by the separation of these components in free induction decays, with α denoting the solid/liquid 1H ratio. When quasi-continuous distributions of relaxation times (T1) of the solid and liquid signal components of cartilage or collagen are computed from experimental relaxation data without imposing the usual NN constraint, valid negative peaks may appear. The features of the distributions, in particular negative peaks, and the fact that peaks at longer times for macromolecular and water protons are at essentially the same T1, are interpreted as the result of a magnetization exchange between these two spin pools. For the only-slightly-hydrated collagen samples, with α>1, the exchange leads to small negative peaks at short T1 times for the macromolecular component. However, for the cartilage, with substantial hydration or for a strongly hydrated collagen sample, both with α1H ratio, α. The solid-to-liquid exchange times are found to be in the range from 10 ms to a few tens of ms at all hydration levels. The results may be of interest for the application of magnetization exchange contrast in the imaging of articular cartilage

  16. RNA Microarray Analysis of Macroscopically Normal Articular Cartilage from Knees Undergoing Partial Medial Meniscectomy: Potential Prediction of the Risk for Developing Osteoarthritis.

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    Muhammad Farooq Rai

    Full Text Available (i To provide baseline knowledge of gene expression in macroscopically normal articular cartilage, (ii to test the hypothesis that age, body-mass-index (BMI, and sex are associated with cartilage RNA transcriptome, and (iii to predict individuals at potential risk for developing "pre-osteoarthritis" (OA based on screening of genetic risk-alleles associated with OA and gene transcripts differentially expressed between normal and OA cartilage.Healthy-appearing cartilage was obtained from the medial femoral notch of 12 knees with a meniscus tear undergoing arthroscopic partial meniscectomy. Cartilage had no radiographic, magnetic-resonance-imaging or arthroscopic evidence for degeneration. RNA was subjected to Affymetrix microarrays followed by validation of selected transcripts by microfluidic digital polymerase-chain-reaction. The underlying biological processes were explored computationally. Transcriptome-wide gene expression was probed for association with known OA genetic risk-alleles assembled from published literature and for comparison with gene transcripts differentially expressed between healthy and OA cartilage from other studies.We generated a list of 27,641 gene transcripts in healthy cartilage. Several gene transcripts representing numerous biological processes were correlated with age and BMI and differentially expressed by sex. Based on disease-specific Ingenuity Pathways Analysis, gene transcripts associated with aging were enriched for bone/cartilage disease while the gene expression profile associated with BMI was enriched for growth-plate calcification and OA. When segregated by genetic risk-alleles, two clusters of study patients emerged, one cluster containing transcripts predicted by risk studies. When segregated by OA-associated gene transcripts, three clusters of study patients emerged, one of which is remarkably similar to gene expression pattern in OA.Our study provides a list of gene transcripts in healthy

  17. A stem cell-based approach to cartilage repair.

    Science.gov (United States)

    Johnson, Kristen; Zhu, Shoutian; Tremblay, Matthew S; Payette, Joshua N; Wang, Jianing; Bouchez, Laure C; Meeusen, Shelly; Althage, Alana; Cho, Charles Y; Wu, Xu; Schultz, Peter G

    2012-05-11

    Osteoarthritis (OA) is a degenerative joint disease that involves the destruction of articular cartilage and eventually leads to disability. Molecules that promote the selective differentiation of multipotent mesenchymal stem cells (MSCs) into chondrocytes may stimulate the repair of damaged cartilage. Using an image-based high-throughput screen, we identified the small molecule kartogenin, which promotes chondrocyte differentiation (median effective concentration = 100 nM), shows chondroprotective effects in vitro, and is efficacious in two OA animal models. Kartogenin binds filamin A, disrupts its interaction with the transcription factor core-binding factor β subunit (CBFβ), and induces chondrogenesis by regulating the CBFβ-RUNX1 transcriptional program. This work provides new insights into the control of chondrogenesis that may ultimately lead to a stem cell-based therapy for osteoarthritis. PMID:22491093

  18. Chondrocytes expressing intracellular collagen type II enter the cell cycle and co-express collagen type I in monolayer culture.

    Science.gov (United States)

    Tekari, Adel; Luginbuehl, Reto; Hofstetter, Willy; Egli, Rainer J

    2014-11-01

    For autologous chondrocyte transplantation, articular chondrocytes are harvested from cartilage tissue and expanded in vitro in monolayer culture. We aimed to characterize with a cellular resolution the synthesis of collagen type II (COL2) and collagen type I (COL1) during expansion in order to further understand why these cells lose the potential to form cartilage tissue when re-introduced into a microenvironment that supports chondrogenesis. During expansion for six passages, levels of transcripts encoding COL2 decreased to COL2/COL1-double positive phenotype during expansion, and the COL2 positive cells were able to enter the cell cycle. While the fraction of COL2 positive cells decreased from 70% to 95%. In parallel to the decrease of the fraction of COL2 positive cells, the cells' potential to form cartilage-like tissue in pellet cultures steadily decreased. Intracellular staining for COL2 enables for characterization of chondrocyte lineage cells in more detail with a cellular resolution, and it may allow predicting the effectiveness of expanded chondrocytes to form cartilage-like tissue. PMID:25043137

  19. Effect of transforming growth factor-β3 on mono and multilayer chondrocytes.

    Science.gov (United States)

    Sefat, Farshid; Youseffi, Mansour; Khaghani, Seyed Ali; Soon, Chin Fhung; Javid, Farideh

    2016-07-01

    Articular cartilage is an avascular and flexible connective tissue found in joints. It produces a cushioning effect at the joints and provides low friction to protect the ends of the bones from wear and tear/damage. It has poor repair capacity and any injury can result pain and loss of mobility. Transforming growth factor-beta (TGF-β), a cytokine superfamily, regulates cell function, including differentiation and proliferation. Although the function of the TGF-βs in various cell types has been investigated, their function in cartilage repair is as yet not fully understood. The effect of TGF-β3 in biological regulation of primary chondrocyte was investigated in this work. TGF-β3 provided fibroblastic morphology to chondrocytes and therefore overall reduction in cell proliferation was observed. The length of the cells supplemented with TGF-β3 were larger than the cells without TGF-β3 treatment. This was caused by the fibroblast like cells (dedifferentiated chondrocytes) which occupied larger areas compared to cells without TGF-β3 addition. The healing process of the model wound closure assay of chondrocyte multilayer was slowed down by TGF-β3, and this cytokine negatively affected the strength of chondrocyte adhesion to the cell culture surface. PMID:27108397

  20. Age-related changes in the sulphation of the chondroitin sulphate linkage region from human articular cartilage aggrecan.

    Science.gov (United States)

    Lauder, R M; Huckerby, T N; Brown, G M; Bayliss, M T; Nieduszynski, I A

    2001-09-01

    The chondroitin sulphate (CS) linkage regions have been isolated from human articular cartilage aggrecan (from 10- to 72-year-olds) by chondroitin ABC endolyase digestion and size-exclusion chromatography. Linkage region hexasaccharides have been characterized and their abundance estimated by high-pH anion-exchange chromatography. The basic structure for the CS linkage region oligosaccharides identified from human aggrecan is as follows: DeltaUA(beta1-3)GalNAc[0S/4S/6S](beta1-4)GlcA(beta1-3)Gal[0S/6S](beta1-3)Gal(beta1-4)Xyl, where DeltaUA represents 4,5-unsaturated hexuronic acid, 4S and 6S represent an O-ester sulphate group on C-4 and C-6 respectively, and 0S represents zero sulphation. There are significant age-related changes in the abundance of the various N-acetylgalactosamine (GalNAc) sulphation forms identified, occurring up to approx. 20 years old. During the period from 10 to 20 years old the level of GalNAc 6-sulphation at the linkage region increases from approx. 43% to approx. 75%, while there is a corresponding reduction in unsulphated (approx. 30% to approx. 20%) and 4-sulphated (approx. 25% to approx. 6%) GalNAc residues. There is also an increase in the incidence of linkage region galactose 6-sulphation (approx. 2% to approx. 10%) which was only observed in linkage regions with GalNAc 6-sulphation. Beyond 20 years old there are few changes in the relative abundance of these GalNAc sulphation variants; however, there is a slight increase in the abundance of 6-sulphation between approx. 20 years old and approx. 40 years old and a slight decrease in its abundance beyond approx. 40 years old. Our data show that in the majority of chains from tissues of all ages the GalNAc residue closest to the linkage region is 6-sulphated, but the level of GalNAc 6-sulphation within the linkage region is lower than the average level observed within the repeat region. PMID:11513754

  1. The Role of Sirtuins in Cartilage Homeostasis and Osteoarthritis.

    Science.gov (United States)

    Dvir-Ginzberg, Mona; Mobasheri, Ali; Kumar, Ashok

    2016-07-01

    The past decade has witnessed many advances in the understanding of sirtuin biology and related regulatory circuits supporting the capacity of these proteins to serve as energy-sensing molecules that contribute to healthspan in various tissues, including articular cartilage. Hence, there has been a significant increase in new investigations that aim to elucidate the mechanisms of sirtuin function and their roles in cartilage biology, skeletal development, and pathologies such as osteoarthritis (OA), rheumatoid arthritis (RA), and intervertebral disc degeneration (IVD). The majority of the work carried out to date has focused on SIRT1, although SIRT6 has more recently become a focus of some investigations. In vivo work with transgenic mice has shown that Sirt1 and Sirt6 are essential for maintaining cartilage homeostasis and that the use of sirtuin-activating molecules such as resveratrol may have beneficial effects on cartilage anabolism. Current thinking is that SIRT1 exerts positive effects on cartilage by encouraging chondrocyte survival, especially under stress conditions, which may provide a mechanism supporting the use of sirtuin small-molecule activators (STACS) for future therapeutic interventions in OA and other degenerative pathologies of joints, especially those that involve articular cartilage. PMID:27289467

  2. Assessment of chemical species of lead accumulated in tidemarks of human articular cartilage by X-ray absorption near-edge structure analysis

    Energy Technology Data Exchange (ETDEWEB)

    Meirer, Florian [Atominstitut, Vienna University of Technology, 1020 Wien (Austria); MiNALab, CMM-Irst, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Italy); Pemmer, Bernhard, E-mail: bpemmer@ati.ac.at [Atominstitut, Vienna University of Technology, 1020 Wien (Austria); Pepponi, Giancarlo [MiNALab, CMM-Irst, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Trento (Italy); Zoeger, Norbert; Wobrauschek, Peter [Atominstitut, Vienna University of Technology, 1020 Wien (Austria); Sprio, Simone; Tampieri, Anna [Istituto di Scienza e Tecnologia dei Materiali Ceramici CNR, Faenca (Italy); Goettlicher, Joerg; Steininger, Ralph; Mangold, Stefan [Institute for Synchrotron Radiation, Karlsruhe Institute of Technology, Campus South, 76344 Eggenstein-Leopoldshafen (Germany); Roschger, Paul [Ludwig Boltzmann Institute of Osteology, Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 4th Medical Department, Hanusch Hospital, Vienna (Austria); Berzlanovich, Andrea [Department of Forensic Medicine, Medical University of Vienna, A-1090 Vienna (Austria); Hofstaetter, Jochen G. [Ludwig Boltzmann Institute of Osteology, Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 4th Medical Department, Hanusch Hospital, Vienna (Austria); Department of Orthopaedics, Vienna General Hospital, Medical University of Vienna, A-1090 Vienna (Austria); Streli, Christina [Atominstitut, Vienna University of Technology, 1020 Wien (Austria)

    2011-03-01

    Lead is a toxic trace element that shows a highly specific accumulation in the transition zone between calcified and non-calcified articular cartilage, the so-called ‘tidemark’. Excellent agreement has been found between XANES spectra of synthetic Pb-doped carbonated hydroxyapatite and spectra obtained in the tidemark region and trabecular bone of normal human samples, confirming that in both tissues Pb is incorporated into the hydroxyapatite crystal structure of bone. During this study the µ-XANES set-up at the SUL-X beamline at ANKA was tested and has proven to be well suited for speciation of lead in human mineralized tissue samples. A highly specific accumulation of the toxic element lead was recently measured in the transition zone between non-calcified and calcified normal human articular cartilage. This transition zone, the so-called ‘tidemark’, is considered to be an active calcification front of great clinical importance. However, little is known about the mechanisms of accumulation and the chemical form of Pb in calcified cartilage and bone. Using spatially resolved X-ray absorption near-edge structure analysis (µ-XANES) at the Pb L{sub 3}-edge, the chemical state of Pb in the osteochondral region was investigated. The feasibility of the µ-XANES set-up at the SUL-X beamline (ANKA synchrotron light source) was tested and confirmed by comparing XANES spectra of bulk Pb-reference compounds recorded at both the XAS and the SUL-X beamline at ANKA. The µ-XANES set-up was then used to investigate the tidemark region of human bone (two patella samples and one femoral head sample). The spectra recorded at the tidemark and at the trabecular bone were found to be highly correlated with the spectra of synthetic Pb-doped carbonated hydroxyapatite, suggesting that in both of these very different tissues Pb is incorporated into the hydroxyapatite structure.

  3. Assessment of chemical species of lead accumulated in tidemarks of human articular cartilage by X-ray absorption near-edge structure analysis

    International Nuclear Information System (INIS)

    Lead is a toxic trace element that shows a highly specific accumulation in the transition zone between calcified and non-calcified articular cartilage, the so-called ‘tidemark’. Excellent agreement has been found between XANES spectra of synthetic Pb-doped carbonated hydroxyapatite and spectra obtained in the tidemark region and trabecular bone of normal human samples, confirming that in both tissues Pb is incorporated into the hydroxyapatite crystal structure of bone. During this study the µ-XANES set-up at the SUL-X beamline at ANKA was tested and has proven to be well suited for speciation of lead in human mineralized tissue samples. A highly specific accumulation of the toxic element lead was recently measured in the transition zone between non-calcified and calcified normal human articular cartilage. This transition zone, the so-called ‘tidemark’, is considered to be an active calcification front of great clinical importance. However, little is known about the mechanisms of accumulation and the chemical form of Pb in calcified cartilage and bone. Using spatially resolved X-ray absorption near-edge structure analysis (µ-XANES) at the Pb L3-edge, the chemical state of Pb in the osteochondral region was investigated. The feasibility of the µ-XANES set-up at the SUL-X beamline (ANKA synchrotron light source) was tested and confirmed by comparing XANES spectra of bulk Pb-reference compounds recorded at both the XAS and the SUL-X beamline at ANKA. The µ-XANES set-up was then used to investigate the tidemark region of human bone (two patella samples and one femoral head sample). The spectra recorded at the tidemark and at the trabecular bone were found to be highly correlated with the spectra of synthetic Pb-doped carbonated hydroxyapatite, suggesting that in both of these very different tissues Pb is incorporated into the hydroxyapatite structure

  4. Three-dimensional spin-lattice relaxation time in the rotating frame imaging and quantitation of articular cartilage at 7.0 T MR

    International Nuclear Information System (INIS)

    in the transitional, calcified layer and global cartilage (F=6.436, P1ρ-weighted imaging of porcine patellar cartilage at 7.0 T with high image quality. T1ρ maps can be used to quantify the laminar structures in 3D-T1ρ-weighted images of articular cartilage, which pave the way to evaluate early osteoarthritis and cartilage regeneration. (authors)

  5. A tetracycline expression system in combination with Sox9 for cartilage tissue engineering.

    Science.gov (United States)

    Yao, Yi; He, Yu; Guan, Qian; Wu, Qiong

    2014-02-01

    Cartilage tissue engineering using controllable transcriptional therapy together with synthetic biopolymer scaffolds shows higher potential for overcoming chondrocyte degradation and constructing artificial cartilages both in vivo and in vitro. Here, the potential regulating tetracycline expression (Tet-on) system was used to express Sox9 both in vivo and in vitro. Chondrocyte degradation was measured in vitro and overcome by Soxf9 expression. Experiments confirmed the feasibility of the combined use of Sox9 and Tet-on system in cartilage tissue engineering. Engineered poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds were seeded with recombinant chondrocytes which were transfected with Tet-induced Sox9 expression; the scaffolds were implanted under the skin of 8-week-old rats. The experimental group was injected with Dox in the abdomen, while the control group was injected with normal saline. After 4 or 8 days of implantation in vivo, the newly formed pieces of articular chondrocytes were taken out and measured. Dox injection in vivo showed positive effect on recombinant chondrocytes, in which Sox9 expression was up-regulated by an inducible system with specific matrix proteins. The results demonstrate this controllable transcriptional therapy is a potential approach for tissue engineering. PMID:24321708

  6. Glucose transport and metabolism in chondrocytes: a key to understanding chondrogenesis, skeletal development and cartilage degradation in osteoarthritis

    OpenAIRE

    A. Mobasheri; Vannucci, S.J.; Bondy, C A; Carter, S D; Innes, J.F.; Arteaga, M F; E. Trujillo; Ferraz, I; Shakibaei, M.; Martín Vasallo, P.

    2002-01-01

    Despite the recognition that degenerative cartilage disorders like osteoarthritis (OA) and osteochondritis dissecans (OCD) may have nutritional abnormalities at the root of their pathogenesis, balanced dietary supplementation programs have played a secondary role in their management. This review emphasizes the importance and role of nutritional factors such as glucose and glucose-derived sugars (i.e. glucosamine sulfate and vitamin C) in the development, ma...

  7. A biomimetic three-dimensional woven composite scaffold for functional tissue engineering of cartilage

    Science.gov (United States)

    Moutos, Franklin T.; Freed, Lisa E.; Guilak, Farshid

    2007-02-01

    Tissue engineering seeks to repair or regenerate tissues through combinations of implanted cells, biomaterial scaffolds and biologically active molecules. The rapid restoration of tissue biomechanical function remains an important challenge, emphasizing the need to replicate structural and mechanical properties using novel scaffold designs. Here we present a microscale 3D weaving technique to generate anisotropic 3D woven structures as the basis for novel composite scaffolds that are consolidated with a chondrocyte-hydrogel mixture into cartilage tissue constructs. Composite scaffolds show mechanical properties of the same order of magnitude as values for native articular cartilage, as measured by compressive, tensile and shear testing. Moreover, our findings showed that porous composite scaffolds could be engineered with initial properties that reproduce the anisotropy, viscoelasticity and tension-compression nonlinearity of native articular cartilage. Such scaffolds uniquely combine the potential for load-bearing immediately after implantation in vivo with biological support for cell-based tissue regeneration without requiring cultivation in vitro.

  8. Texture analysis of articular cartilage traumatic changes in the knee calculated from morphological 3.0 T MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Boutsikou, Konstantina [Department of Medical Radiologic Technology, Technological Educational Institute of Athens, Ag.Spyridonos, Egaleo, Athens 12210 (Greece); Kostopoulos, Spiros; Glotsos, Dimitris; Cavouras, Dionisis [Department of Medical Instruments Technology, Technological Educational Institute of Athens, Ag.Spyridonos, Egaleo, Athens 12210 (Greece); Lavdas, Eleftherios; Oikonomou, Georgia [Department of Medical Radiologic Technology, Technological Educational Institute of Athens, Ag.Spyridonos, Egaleo, Athens 12210 (Greece); Malizos, Konstantinos [Department of Orthopaedic Surgery, University of Thessaly, School of Health Sciences, University Hospital of Larissa, Biopolis, Larissa 41110 (Greece); Fezoulidis, Ioannis V. [Department of Radiology, University of Thessaly, School of Health Sciences, University Hospital of Larissa, Biopolis, Larissa 41110 (Greece); Vlychou, Marianna, E-mail: mvlychou@med.uth.gr [Department of Radiology, University of Thessaly, School of Health Sciences, University Hospital of Larissa, Biopolis, Larissa 41110 (Greece)

    2013-08-15

    Objectives: In the present work, we aim to identify changes in the cartilage texture of the injured knee in young, physically active, patients by computer analysis of MRI images based on 3.0 T morphological sequences. Methods: Fifty-three young patients with training injury or trauma in one knee underwent MRI and arthroscopy. Textural features were computed from the MRI images of the knee-cartilages and two classes were formed of 28 normal and 16 with pathology only in the medial femoral condyle (MFC) cartilage. Results: Textural features with statistically significant differences between the two classes were found only at the MFC and the medial tibial condyle (MTC) areas. Three features-combinations, at the MFC or the MTC, maximized the between classes separation, thus, rendering alterations in cartilage texture due to injury more evident. The MFC cartilage in the pathology class was found more inhomogeneous in the distribution of gray-levels and of lower texture anisotropy and the opposed MTC cartilage, though normal on MRI and arthroscopy, was found to have lower texture anisotropy than cartilage in the normal class. Conclusion: Texture analysis may be used as an adjunct to morphological MR imaging for improving the detection of subtle cartilage changes and contributes to early therapeutic approach.

  9. Texture analysis of articular cartilage traumatic changes in the knee calculated from morphological 3.0 T MR imaging

    International Nuclear Information System (INIS)

    Objectives: In the present work, we aim to identify changes in the cartilage texture of the injured knee in young, physically active, patients by computer analysis of MRI images based on 3.0 T morphological sequences. Methods: Fifty-three young patients with training injury or trauma in one knee underwent MRI and arthroscopy. Textural features were computed from the MRI images of the knee-cartilages and two classes were formed of 28 normal and 16 with pathology only in the medial femoral condyle (MFC) cartilage. Results: Textural features with statistically significant differences between the two classes were found only at the MFC and the medial tibial condyle (MTC) areas. Three features-combinations, at the MFC or the MTC, maximized the between classes separation, thus, rendering alterations in cartilage texture due to injury more evident. The MFC cartilage in the pathology class was found more inhomogeneous in the distribution of gray-levels and of lower texture anisotropy and the opposed MTC cartilage, though normal on MRI and arthroscopy, was found to have lower texture anisotropy than cartilage in the normal class. Conclusion: Texture analysis may be used as an adjunct to morphological MR imaging for improving the detection of subtle cartilage changes and contributes to early therapeutic approach

  10. MR imaging of the articular cartilage of the knee with arthroscopy as gold standard: assessment of methodological quality of clinical studies

    International Nuclear Information System (INIS)

    The purpose of this study was to assess the methodological quality of articles addressing the value of MR imaging of the knee cartilage with arthroscopy as a standard. Relevant papers were selected after Medline review (MEDLINE database search including the terms ''cartilage'' ''knee'', ''MR'' and ''arthroscopy''). Two observers reviewed independently 29 selected articles to determine how each study had met 15 individual standards that had been previously developed to assess the methodological quality of clinical investigations. The following criteria were met in variable percentage of articles including adequate definition of purpose (100%), statistical analysis (90%), avoidance of verification bias (86%), patient population description (83%), reference standard (79%), review bias (79%), study design (66%), inclusion criteria (41%) and method of analysis (41.5%), avoidance of diagnostic-review bias (24%), exclusion criteria (21%), indeterminate examination results (17%), analysis criteria (14%), interobserver reliability (14%) and intraobserver reliability (7%). The assessment of the methodological quality of clinical investigations addressing the value of MR imaging in the evaluation of the articular cartilage of the knee with arthroscopy as the standard of reference demonstrated that several standards were rarely met in the literature. Efforts should be made to rely on clearly defined lesion criteria and to determine reliability of the observations. (orig.)

  11. Comparative digital cartilage histology for human and common osteoarthritis models

    Directory of Open Access Journals (Sweden)

    Pedersen DR

    2013-02-01

    Full Text Available Douglas R Pedersen, Jessica E Goetz, Gail L Kurriger, James A MartinDepartment of Orthopaedics and Rehabilitation, University of Iowa, Iowa City, IA, USAPurpose: This study addresses the species-specific and site-specific details of weight-bearing articular cartilage zone depths and chondrocyte distributions among humans and common osteoarthritis (OA animal models using contemporary digital imaging tools. Histological analysis is the gold-standard research tool for evaluating cartilage health, OA severity, and treatment efficacy. Historically, evaluations were made by expert analysts. However, state-of-the-art tools have been developed that allow for digitization of entire histological sections for computer-aided analysis. Large volumes of common digital cartilage metrics directly complement elucidation of trends in OA inducement and concomitant potential treatments.Materials and methods: Sixteen fresh human knees, 26 adult New Zealand rabbit stifles, and 104 bovine lateral plateaus were measured for four cartilage zones and the cell densities within each zone. Each knee was divided into four weight-bearing sites: the medial and lateral plateaus and femoral condyles.Results: One-way analysis of variance followed by pairwise multiple comparisons (Holm–Sidak method at a significance of 0.05 clearly confirmed the variability between cartilage depths at each site, between sites in the same species, and between weight-bearing articular cartilage definitions in different species.Conclusion: The present study clearly demonstrates multisite, multispecies differences in normal weight-bearing articular cartilage, which can be objectively quantified by a common digital histology imaging technique. The clear site-specific differences in normal cartilage must be taken into consideration when characterizing the pathoetiology of OA models. Together, these provide a path to consistently analyze the volume and variety of histologic slides necessarily generated

  12. Relationship between knee alignment and T1ρ values of articular cartilage and menisci in patients with knee osteoarthritis

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ligong, E-mail: ligong.wang@hotmail.com [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); School of Radiation Medicine and Protection, Medical College of Soochow University, School for Radiological and interdisciplinary Sciences (RAD-X), Soochow University, Suzhou, Jiangsu 215123 (China); Vieira, Renata La Rocca, E-mail: relarocca@gmail.com [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Rybak, Leon D., E-mail: Leon.Rybak@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Babb, James S., E-mail: James.Babb@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Chang, Gregory, E-mail: gregory.chang@nyumc.org [Quantitative Multinuclear Musculoskeletal Imaging Group (QMMIG), Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY 10016 (United States); Krasnokutsky, Svetlana, E-mail: Svetlana.Krasnokutsky@nyumc.org [Department of Rheumatology, New York University Hospital for Joint Diseases, 301 East 17th Street, New York, NY 10003 (United States); Abramson, Steven, E-mail: StevenB.Abramson@nyumc.org [Department of Rheumatology, New York University Hospital for Joint Diseases, 301 East 17th Street, New York, NY 10003 (United States); and others

    2013-11-01

    Objective: To assess the relationship between knee alignment and subregional T1ρ values of the femorotibial cartilage and menisci in patients with mild (Kellgren–Lawrence grade 1) to moderate (KL3) osteoarthritis (OA) at 3 T. Materials and methods: 26 subjects with a clinical diagnosis of KL1-3 OA were included and subdivided into three subgroups: varus, valgus, and neutral. All subjects were evaluated on a 3 T MR scanner. Mann–Whitney and Wilcoxon signed rank tests were performed to determine any statistically significant differences in subregional T1ρ values of femorotibial cartilage and menisci among the three subgroups of KL1-3 OA patients. Results: Medial femoral anterior cartilage subregion in varus group had significantly higher (p < 0.05) T1ρ values than all cartilage subregions in valgus group. Medial tibial central cartilage subregion had significantly higher T1ρ values (p < 0.05) than lateral tibial central cartilage subregion in varus group. The posterior horn of the medial meniscus in neutral group had significantly higher T1ρ values (p < 0.0029) than all meniscus subregions in valgus group. Conclusion: There exists some degree of association between knee alignment and subregional T1ρ values of femorotibial cartilage and menisci in patients with clinical OA.

  13. Priming Adipose-Derived Mesenchymal Stem Cells with Hyaluronan Alters Growth Kinetics and Increases Attachment to Articular Cartilage

    Directory of Open Access Journals (Sweden)

    Peter Succar

    2016-01-01

    Full Text Available Background. Biological therapeutics such as adipose-derived mesenchymal stem cell (MSC therapy are gaining acceptance for knee-osteoarthritis (OA treatment. Reports of OA-patients show reductions in cartilage defects and regeneration of hyaline-like-cartilage with MSC-therapy. Suspending MSCs in hyaluronan commonly occurs in animals and humans, usually without supporting data. Objective. To elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics. Methods. Using a range of hyaluronan concentrations, we measured MSC adherence and proliferation on culture plastic surfaces and a novel cartilage-adhesion assay. We employed time-course and dispersion imaging to assess MSC binding to cartilage. Cytokine profiling was also conducted on the MSC-secretome. Results. Hyaluronan had dose-dependent effects on growth kinetics of MSCs at concentrations of entanglement point (1 mg/mL. At higher concentrations, viscosity effects outweighed benefits of additional hyaluronan. The cartilage-adhesion assay highlighted for the first time that hyaluronan-primed MSCs increased cell attachment to cartilage whilst the presence of hyaluronan did not. Our time-course suggested patients undergoing MSC-therapy for OA could benefit from joint-immobilisation for up to 8 hours. Hyaluronan also greatly affected dispersion of MSCs on cartilage. Conclusion. Our results should be considered in future trials with MSC-therapy using hyaluronan as a vehicle, for the treatment of OA.

  14. Relationship between knee alignment and T1ρ values of articular cartilage and menisci in patients with knee osteoarthritis

    International Nuclear Information System (INIS)

    Objective: To assess the relationship between knee alignment and subregional T1ρ values of the femorotibial cartilage and menisci in patients with mild (Kellgren–Lawrence grade 1) to moderate (KL3) osteoarthritis (OA) at 3 T. Materials and methods: 26 subjects with a clinical diagnosis of KL1-3 OA were included and subdivided into three subgroups: varus, valgus, and neutral. All subjects were evaluated on a 3 T MR scanner. Mann–Whitney and Wilcoxon signed rank tests were performed to determine any statistically significant differences in subregional T1ρ values of femorotibial cartilage and menisci among the three subgroups of KL1-3 OA patients. Results: Medial femoral anterior cartilage subregion in varus group had significantly higher (p < 0.05) T1ρ values than all cartilage subregions in valgus group. Medial tibial central cartilage subregion had significantly higher T1ρ values (p < 0.05) than lateral tibial central cartilage subregion in varus group. The posterior horn of the medial meniscus in neutral group had significantly higher T1ρ values (p < 0.0029) than all meniscus subregions in valgus group. Conclusion: There exists some degree of association between knee alignment and subregional T1ρ values of femorotibial cartilage and menisci in patients with clinical OA

  15. A comparison of multi-echo spin-echo and triple-echo steady-state T2 mapping for in vivo evaluation of articular cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Juras, Vladimir; Szomolanyi, Pavol [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-Guided Therapy, Vienna (Austria); Institute of Measurement Science, Department of Imaging Methods, Bratislava (Slovakia); Bohndorf, Klaus; Kronnerwetter, Claudia; Hager, Benedikt; Zbyn, Stefan [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-Guided Therapy, Vienna (Austria); Heule, Rahel; Bieri, Oliver [University of Basel Hospital, Division of Radiological Physics, Department of Radiology, Basel (Switzerland); Trattnig, Siegfried [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-Guided Therapy, Vienna (Austria); Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna (Austria); Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Austrian Cluster for Tissue Regeneration, Vienna (Austria)

    2016-06-15

    To assess the clinical relevance of T{sub 2} relaxation times, measured by 3D triple-echo steady-state (3D-TESS), in knee articular cartilage compared to conventional multi-echo spin-echo T{sub 2}-mapping. Thirteen volunteers and ten patients with focal cartilage lesions were included in this prospective study. All subjects underwent 3-Tesla MRI consisting of a multi-echo multi-slice spin-echo sequence (CPMG) as a reference method for T{sub 2} mapping, and 3D TESS with the same geometry settings, but variable acquisition times: standard (TESSs 4:35min) and quick (TESSq 2:05min). T{sub 2} values were compared in six different regions in the femoral and tibial cartilage using a Wilcoxon signed ranks test and the Pearson correlation coefficient (r). The local ethics committee approved this study, and all participants gave written informed consent. The mean quantitative T{sub 2} values measured by CPMG (mean: 46±9ms) in volunteers were significantly higher compared to those measured with TESS (mean: 31±5ms) in all regions. Both methods performed similarly in patients, but CPMG provided a slightly higher difference between lesions and native cartilage (CPMG: 90ms→61ms [31%],p=0.0125;TESS 32ms→24ms [24%],p=0.0839). 3D-TESS provides results similar to those of a conventional multi-echo spin-echo sequence with many benefits, such as shortening of total acquisition time and insensitivity to B{sub 1} and B{sub 0} changes. (orig.)

  16. An evaluation of chondrocyte morphology and gene expression on superhydrophilic vertically-aligned multi-walled carbon nanotube films

    Energy Technology Data Exchange (ETDEWEB)

    Antonioli, Eliane, E-mail: eliane.antonioli@einstein.br [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Lobo, Anderson O., E-mail: aolobo@univap.br [Laboratory of Biomedical Nanotechnology, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Ferretti, Mario, E-mail: ferretti@einstein.br [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Ortophedic Division, Federal University of Sao Paulo, SP (Brazil); Cohen, Moises, E-mail: m.cohen@uol.com.br [Research and Education Institute, Hospital Israelita Albert Einstein, Sao Paulo, SP (Brazil); Ortophedic Division, Federal University of Sao Paulo, SP (Brazil); Marciano, Fernanda R., E-mail: femarciano@uol.com.br [Laboratory of Biomedical Nanotechnology, Universidade do Vale do Paraiba, Sao Jose dos Campos, Sao Paulo (Brazil); Corat, Evaldo J., E-mail: corat@las.inpe.br [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, Sao Paulo (Brazil); Trava-Airoldi, Vladimir J., E-mail: vladimir@las.inpe.br [Laboratorio Associado de Sensores e Materiais, Instituto Nacional de Pesquisas Espaciais, Sao Jose dos Campos, Sao Paulo (Brazil)

    2013-03-01

    Cartilage serves as a low-friction and wear-resistant articulating surface in diarthrodial joints and is also important during early stages of bone remodeling. Recently, regenerative cartilage research has focused on combinations of cells paired with scaffolds. Superhydrophilic vertically aligned carbon nanotubes (VACNTs) are of particular interest in regenerative medicine. The aim of this study is to evaluate cell expansion of human articular chondrocytes on superhydrophilic VACNTs, as well as their morphology and gene expression. VACNT films were produced using a microwave plasma chamber on Ti substrates and submitted to an O{sub 2} plasma treatment to make them superhydrophilic. Human chondrocytes were cultivated on superhydrophilic VACNTs up to five days. Quantitative RT-PCR was performed to measure type I and type II Collagen, Sox9, and Aggrecan mRNA expression levels. The morphology was analyzed by scanning electron microscopy (SEM) and confocal microscopy. SEM images demonstrated that superhydrophilic VACNTs permit cell growth and adhesion of human chondrocytes. The chondrocytes had an elongated morphology with some prolongations. Chondrocytes cultivated on superhydrophilic VACNTs maintain the level expression of Aggrecan, Sox9, and Collagen II determined by qPCR. This study was the first to indicate that superhydrophilic VACNTs may be used as an efficient scaffold for cartilage or bone repair. Highlights: Black-Right-Pointing-Pointer Chondrocytes were cultivated on Superhydrophilic Vertically Aligned Multiwall Carbon Nanotubes (VACNT). Black-Right-Pointing-Pointer We have shown a correlation between gene expression and thermodynamics aspects. Black-Right-Pointing-Pointer Superhydrhophilic VACNT will be an excellent substrate for cartilage and bone tissue regeneration.

  17. An evaluation of chondrocyte morphology and gene expression on superhydrophilic vertically-aligned multi-walled carbon nanotube films

    International Nuclear Information System (INIS)

    Cartilage serves as a low-friction and wear-resistant articulating surface in diarthrodial joints and is also important during early stages of bone remodeling. Recently, regenerative cartilage research has focused on combinations of cells paired with scaffolds. Superhydrophilic vertically aligned carbon nanotubes (VACNTs) are of particular interest in regenerative medicine. The aim of this study is to evaluate cell expansion of human articular chondrocytes on superhydrophilic VACNTs, as well as their morphology and gene expression. VACNT films were produced using a microwave plasma chamber on Ti substrates and submitted to an O2 plasma treatment to make them superhydrophilic. Human chondrocytes were cultivated on superhydrophilic VACNTs up to five days. Quantitative RT-PCR was performed to measure type I and type II Collagen, Sox9, and Aggrecan mRNA expression levels. The morphology was analyzed by scanning electron microscopy (SEM) and confocal microscopy. SEM images demonstrated that superhydrophilic VACNTs permit cell growth and adhesion of human chondrocytes. The chondrocytes had an elongated morphology with some prolongations. Chondrocytes cultivated on superhydrophilic VACNTs maintain the level expression of Aggrecan, Sox9, and Collagen II determined by qPCR. This study was the first to indicate that superhydrophilic VACNTs may be used as an efficient scaffold for cartilage or bone repair. Highlights: ► Chondrocytes were cultivated on Superhydrophilic Vertically Aligned Multiwall Carbon Nanotubes (VACNT). ► We have shown a correlation between gene expression and thermodynamics aspects. ► Superhydrhophilic VACNT will be an excellent substrate for cartilage and bone tissue regeneration.

  18. Immunomagnetic sorting and differentiation of mesenchymal stem cells in human articular cartilage%人关节软骨来源CD105~+/CD166~+间充质干细胞的分选及其多向分化特性的鉴定

    Institute of Scientific and Technical Information of China (English)

    常红星; 杨柳; 李忠; 陈光兴; 刘军; 文亚名; 戴刚

    2009-01-01

    目的 建立免疫磁珠技术高效分选人关节软骨CD166~+/CD105~+间充质干细胞(MSCs)的方法,并鉴定其多向分化特性.方法 酶消化法获取5例手术切除的膝关节软骨组织细胞,并行原代(P~0代)和传代(P~2、P~4、P~6代)培养;流式细胞仪检测其中CD166~+/CD105~+细胞百分比.比较免疫磁珠连续法与间断法分选P~4代培养细胞中CD166~+/CD105~+细胞的所需时间、分选细胞活度及其百分比和收获率.对连续法分选CD166~+/CD105~+细胞进行成骨、成软骨、成脂肪诱导,Gomori钙钴法碱性磷酸酶(Ale)、Ⅱ型胶原免疫组化、油红O染色检测其分化特性.结果 人关节软骨组织分离细胞和原代培养细胞中的CD105~+/CD166~+细胞百分比较低[(1.13±0.68)%、(5.16±3.59)%],传代培养细胞中的CD105~+/CD166~+细胞百分比随传代次数增加而明显增高[P~2、P~4、P~6代培养细胞中CD166~+/CD105~+细胞百分比分别为(12.68±2.59)%、(17.81±3.80)%、(19.36±3.93)%](P0.05).免疫磁珠连续法分选P4代培养细胞中CD105~+/CD166~+细胞的百分比高于间断分选法[(93.8±3.95)%vs(90.1±2.43)%,P0.05).连续法分选CD166~+/CD105~+细胞成骨诱导后ALP染色阳性;成软骨诱导前Ⅱ型胶原弱阳性,诱导后Ⅱ型胶原附性;成脂肪诱导后,细胞内可见脂肪滴,油红O染色阳性.结论 人关节软骨P~4、P~6代培养细胞中的MSCs比例较高.免疫磁珠连续法能够高效了分选人关节软骨MSCs,所分选的MSCs具有成骨、成软骨及成脂肪分化功能.%Objective To establish a simple and feasible method of immunomagnetic separation of CD166~+/CD105~+ mesenchymal stem cells (MSCs) from human articular cartilage. Methods The CD166~+/ CD105~+ MSCs in chondrocytes were isolated and cultured from 5 tissue samples of human knee articular carti-lage with primary osteoarthritis ( OA). The percentage of double positive cells were analyzed by flow cytometry just after digested, and in passages 0,2,4 and 6

  19. Research progress of knee articular cartilage injury%方申雲范海涛刘蜀彬

    Institute of Scientific and Technical Information of China (English)

    方申雲; 范海涛; 刘蜀彬

    2014-01-01

    本文通过系统回顾分析中老年患者膝关节软骨损伤的流行病学特点、病因及可能的发病机制,进而探讨软骨损伤后的危害性,归纳外科治疗膝关节软骨损伤术式的选择及存在的优缺点,以及软骨损伤最新研究进展情况。%Based review of systems analysis in elderly patients with knee cartilage injury epidemiology,etiology and pathogenesis,then discuss the dangers of cartilage injury,summed up selection of surgical treatment of knee cartilage damage and there are advantages and disadvantages,as well as cartilage damage study on the latest development.

  20. Altered swelling and ion fluxes in articular cartilage as a biomarker in osteoarthritis and joint immobilization: a computational analysis

    OpenAIRE

    Manzano, Sara; Manzano, Raquel; Doblaré, Manuel; Doweidar, Mohamed Hamdy

    2015-01-01

    In healthy cartilage, mechano-electrochemical phenomena act together to maintain tissue homeostasis. Osteoarthritis (OA) and degenerative diseases disrupt this biological equilibrium by causing structural deterioration and subsequent dysfunction of the tissue. Swelling and ion flux alteration as well as abnormal ion distribution are proposed as primary indicators of tissue degradation. In this paper, we present an extension of a previous three-dimensional computational model of the cartilage ...

  1. Tauroursodeoxycholic acid suppresses endoplasmic reticulum stress in the chondrocytes of patients with osteoarthritis.

    Science.gov (United States)

    Liu, Chao; Cao, Yongping; Yang, Xin; Shan, Pengcheng; Liu, Heng

    2015-10-01

    The main pathogenic events in osteoarthritis (OA) include loss and abnormal remodeling of cartilage extracellular matrix. The present study aimed to evaluate the protective effect of tauroursodeoxycholic acid on chondrocyte apoptosis induced by endoplasmic reticulum (ER) stress. Articular cartilage tissues were collected from 18 patients who underwent total knee arthroplasty and were analyzed histologically. Subsequently, chondrocyte apoptosis was assessed by TUNEL. Quantitative polymerase chain reaction and western blot analysis were employed to evaluate gene and protein expression, respectively, of ER stress markers, including glucose‑regulated protein 78 (GRP78), growth arrest and DNA‑damage‑inducible gene 153 (GADD153) and caspase‑12 along with type II collagen. Chondrocytes obtained from osteoarthritis patients at different stages were cultured in three conditions including: No treatment (CON group), tunicamycin treatment to induce ER stress (ERS group) and tauroursodeoxycholic acid treatment after 4 h of tunicamycin (TDA group); and cell proliferation, apoptosis, function and ER stress level were assessed. Degradation of cartilage resulted in histological damage with more apoptotic cartilage cells observed. Of note, GRP78, GADD153 and caspase‑12 mRNA and protein expression increased gradually from grade I to III cartilage tissue, while type II collagen expression decreased. Tunicamycin induced ER stress, as shown by a high expression of ER stress markers, reduced cell proliferation, increased apoptosis and decreased synthesis of type II collagen. Notably, tauroursodeoxycholic acid treatment resulted in the improvement of tunicamycin‑induced ER stress. These results indicated that ER stress is highly involved in the tunicamycin‑induced apoptosis in chondrocytes, which can be prevented by tauroursodeoxycholic acid. PMID:26238983

  2. The search for negative amplitude components in quasi-continuous distributions of relaxation times: the example of {sup 1}H magnetization exchange in articular cartilage and hydrated collagen

    Energy Technology Data Exchange (ETDEWEB)

    Fantazzini, Paola; Galassi, Francesca [Department of Physics, University of Bologna, Viale Berti Pichat 6/2, 40127 Bologna (Italy); Bortolotti, Villiam [Department of DICAM, University of Bologna, Viale del Risorgimento 2, 40136 Bologna (Italy); Brown, Robert J S [953 West Bonita Avenue, Claremont, CA 91711-4193 (United States); Vittur, Franco, E-mail: paola.fantazzini@unibo.it [Department of Life Sciences, University of Trieste, via Giorgeri 1, 24137 (Italy)

    2011-06-15

    When inverting nuclear magnetic resonance relaxation data in order to obtain quasi-continuous distributions of relaxation times for fluids in porous media, it is common practice to impose a non-negative (NN) constraint on the distributions. While this approach can be useful in reducing the effects of data distortion and/or preventing wild oscillations in the distributions, it may give misleading results in the presence of real negative amplitude components. Here, some examples of valid negative components for articular cartilage and hydrated collagen are given. Articular cartilage is a connective tissue, consisting mainly of collagen, proteoglycans and water, which can be considered, in many aspects, as a porous medium. Separate T{sub 1} relaxation data are obtained for low-mobility ('solid') macromolecular {sup 1}H and for higher-mobility ('liquid') {sup 1}H by the separation of these components in free induction decays, with {alpha} denoting the solid/liquid {sup 1}H ratio. When quasi-continuous distributions of relaxation times (T{sub 1}) of the solid and liquid signal components of cartilage or collagen are computed from experimental relaxation data without imposing the usual NN constraint, valid negative peaks may appear. The features of the distributions, in particular negative peaks, and the fact that peaks at longer times for macromolecular and water protons are at essentially the same T{sub 1}, are interpreted as the result of a magnetization exchange between these two spin pools. For the only-slightly-hydrated collagen samples, with {alpha}>1, the exchange leads to small negative peaks at short T{sub 1} times for the macromolecular component. However, for the cartilage, with substantial hydration or for a strongly hydrated collagen sample, both with {alpha}<<1, the behavior is reversed, with a negative peak for water at short times. The validity of a negative peak may be accepted (dismissed) by a high (low) cost of NN in error of fit

  3. 3D Culture of Chondrocytes in Gelatin Hydrogels with Different Stiffness

    Directory of Open Access Journals (Sweden)

    Xiaomeng Li

    2016-07-01

    Full Text Available Gelatin hydrogels can mimic the microenvironments of natural tissues and encapsulate cells homogeneously, which makes them attractive for cartilage tissue engineering. Both the mechanical and biochemical properties of hydrogels can affect the phenotype of chondrocytes. However, the influence of each property on chondrocyte phenotype is unclear due to the difficulty in separating the roles of these properties. In this study, we aimed to study the influence of hydrogel stiffness on chondrocyte phenotype while excluding the role of biochemical factors, such as adhesion site density in the hydrogels. By altering the degree of methacryloyl functionalization, gelatin hydrogels with different stiffnesses of 3.8, 17.1, and 29.9 kPa Young’s modulus were prepared from the same concentration of gelatin methacryloyl (GelMA macromers. Bovine articular chondrocytes were encapsulated in the hydrogels and cultured for 14 days. The influence of hydrogel stiffness on the cell behaviors including cell viability, cell morphology, and maintenance of chondrogenic phenotype was evaluated. GelMA hydrogels with high stiffness (29.9 kPa showed the best results on maintaining chondrogenic phenotype. These results will be useful for the design and preparation of scaffolds for cartilage tissue engineering.

  4. Lactoferrin inhibits dexamethasone-induced chondrocyte impairment from osteoarthritic cartilage through up-regulation of extracellular signal-regulated kinase 1/2 and suppression of FASL, FAS, and Caspase 3

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Yihui [Department of Orthopaedics, Yangpu District Central Hospital Affiliated to Tongji University School of Medicine, 450 Tengyue Road, Shanghai (China); Xue, Huaming [Department of Orthopaedics, Yangpu District Central Hospital Affiliated to Tongji University School of Medicine, 450 Tengyue Road, Shanghai (China); Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom); Francis, Wendy [Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom); Davies, Andrew P. [Department of Orthopaedics and Trauma, Moriston Hospital, Swansea (United Kingdom); Pallister, Ian; Kanamarlapudi, Venkateswarlu [Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom); Xia, Zhidao, E-mail: zhidao.xia@gmail.com [Institute of Life Science, College of Medicine, Swansea University, Singleton Park (United Kingdom)

    2013-11-08

    Highlights: •Dex exerts dose-dependant inhibition of HACs viability and induction of apoptosis. •Dex-induced impairment of chondrocytes was attenuated by rhLF. •ERK and FASL/FAS signaling are involved in the effects of rhLF. •OA patients with glucocorticoid-induced cartilage damage may benefit from treatment with rhLF. -- Abstract: Dexamethasone (Dex) is commonly used for osteoarthritis (OA) with excellent anti-inflammatory and analgesic effect. However, Dex also has many side effects following repeated use over prolonged periods mainly through increasing apoptosis and inhibiting proliferation. Lactoferrin (LF) exerts significantly anabolic effect on many cells and little is known about its effect on OA chondrocytes. Therefore, the aim of this study is to investigate whether LF can inhibit Dex-induced OA chondrocytes apoptosis and explore its possible molecular mechanism involved in. MTT assay was used to determine the optimal concentration of Dex and recombinant human LF (rhLF) on chondrocytes at different time and dose points. Chondrocytes were then stimulated with Dex in the absence or presence of optimal concentration of rhLF. Cell proliferation and viability were evaluated using MTT and LIVE/DEAD assay, respectively. Cell apoptosis was evaluated by multi-parameter apoptosis assay kit using both confocal microscopy and flow cytometry, respectively. The expression of extracellular signal-regulated kinase (ERK), FAS, FASL, and Caspase-3 (CASP3) at the mRNA and protein levels were examined by real-time polymerase chain reaction (PCR) and immunocytochemistry, respectively. The optimal concentration of Dex (25 μg/ml) and rhLF (200 μg/ml) were chosen for the following experiments. rhLF significantly reversed the detrimental effect of Dex on chondrocytes proliferation, viability, and apoptosis. In addition, rhLF significantly prevented Dex-induced down-regulation of ERK and up-regulation of FAS, FASL, and CASP3. These findings demonstrated that rhLF acts as

  5. Reduced articular cartilage thickness in joints without a history of active arthritis in children with juvenile idiopathic arthritis

    DEFF Research Database (Denmark)

    Pradsgaard, Dan Østergaard; Spannow, Anne Helene; Heuck, Carsten;

    joint cartilage thickness (Cth) between healthy children and JIA children measured by US (1). But are there any differences in Cth measured by US between healthy children and joints without a history of activity among JIA children’s. Aim: To investigate a possible effect of the inflammatory process on......, and 189 2nd PIP joints. Cartilage thickness was measured perpendicular to the bone surface. History of joint activity was found by review of medical records. An age-, and sex-matched healthy cohort investigated in a previous study served as a control group (2), age, 10.9 (6-16), girls/boys (177...... joints never directly affected by arthritic activity during the history of the child’s disease course. Furthermore we wanted to compare joint cartilage thickness within the JIA group in joints with or without a history of activity. Methods: We included 95 Danish JIA children. Age, mean (range) 10...

  6. O gel de plasma rico em plaquetas propicia a regeneração da cartilagem articular do joelho de ovelhas Platelet-rich plasma gel promotes regeneration of articular cartilage in knees of sheeps

    Directory of Open Access Journals (Sweden)

    Márcio de Oliveira Carneiro

    2013-04-01

    Full Text Available OBJETIVO: Avaliar a regeneração da cartilagem articular em defeitos osteocondrais do joelho induzidos pelo plasma rico em plaquetas (PRP autógeno. MÉTODOS: Defeitos osteocondrais produzidos no sulco troclear de ambos os joelhos de dez ovelhas foram preenchidos com PRP autógeno à direita e deixados vazios à esquerda. Avaliação macroscópica e histológica foram efetuadas 12 semanas mais tarde. Os resultados foram avaliados por um escore geral de ambas as avaliações macroscópica e histológica comparativamente entre os lados por meio do teste pareado de Wilcoxon. RESULTADOS: o aspecto macroscópico não foi uniforme entre os animais, nem diferiu entre os joelhos direitos e esquerdos (p=0,03125; em nenhum caso o tecido regenerado se nivelou com a cartilagem normal circundante. Ao exame histológico, cartilagem aparentemente normal não foi detectada em nenhum joelho, mas uma cartilagem pouco diferenciada estava presente em sete joelhos direitos e em três joelhos esquerdos. Tecido fibrocartilaginoso estava presente nos joelhos restantes, com diferença significante no escore geral entre os joelhos direitos e esquerdos (p=0,0313. CONCLUSÃO: o PRP como usado neste estudo tem propriedades reparativas da cartilagem articular no joelho de ovelhas, principalmente por estimular a formação de tecido fibrocartilaginoso. Trabalho Experimental.OBJECTIVE: to assess the regeneration of osteochondral defects in the joint cartilage of the knee induced by autologous platelet-rich plasma (pRp. METHODS: osteochondral defects produced in the trochlear groove of both knees of ten sheep; defects of the right knees were filled with autologous pRp and the left knees were left unfilled. macroscopic and microscopic evaluation was carried out 12 week later. the results were evaluated by the total score of both macroscopic and microscopic evaluations comparing the two sides through the wilcoxon paired test. RESULTS: macroscopic appearance was not uniform among

  7. Optimized alkylated cyclodextrin polysulphates with reduced risks on thromboembolic accidents improve osteoarthritic chondrocyte metabolism

    OpenAIRE

    Groeneboer, Sara; Lambrecht, Stijn; Dhollander, Aad; Jacques, Peggy; Cruyssen, Bert Vander; Lories, Rik J.; Devreese, Katrien; Chiers, Koen; Elewaut, Dirk; Verbruggen, Gust

    2011-01-01

    Objectives. To compare the ability of different cyclodextrin polysulphate (CDPS) derivatives to affect human articular cartilage cell metabolism in vitro. Methods. OA chondrocytes were cultured in alginate and exposed to 5 µg/ml of 2,3,6-tri-O-methyl-β-cyclodextrin (ME-CD), 2,3-di-O-methyl-6-sulphate-β-cyclodextrin (ME-CD-6-S), 2,6-di-O-methyl-3-sulphate-β-cyclodextrin (ME-CD-3-S), (2-carboxyethyl)-β-CDPS (CE-CDPS), (2-hydroxypropyl)-β-CDPS (HP-CDPS), 6-monoamino-6-monodeoxy-β-CDPS (MA-CDPS) ...

  8. 透明质酸对关节软骨蛋白聚糖aggrecan的影响%Effect of hyaluronic acid on articular cartilage proteoglycan aggrecan

    Institute of Scientific and Technical Information of China (English)

    杜国辉; 屈爱存; 陈建英; 贺艳丽

    2011-01-01

    目的 研究关节腔注射透明质酸对兔骨关节炎软骨基质的保护作用.方法 关节骨液用软骨素酶ABC降解,丹磺酰肼柱前衍生.采用NH2色谱柱,流动相为乙腈-10 mmol/L醋酸溶液-10 mmol/L醋酸钠溶液(7616:8),荧光检测器检测,激发波长350 nm,发射波长530 nm,流速为1mL/min.结果 透明质酸可减少兔关节滑液中C4S、C6S的含量.结论 关节腔注射透明质酸可抑制兔软骨蛋白聚糖的降解或上调蛋白聚糖的合成,维持关节软骨正常的新陈代谢.%Purpose To investigate the protective effect of intra-articular injection of hyaluronic acid on cartilage matrix in rabbit osteoarthritis. Methods Joint synovial fluid was degraded by chondroitinase ABC, and then derived with dansylhydrazine. The derivatized sample was separated on NH2 column. The mobile phase of acetonitrile- acetic acid- sodium acetate (76:16:8) was used. Detected with fluorescence detector, the excitation wavelength (λex) and emission wavelength (λem) were 350 and 530 nm, respectively. The flow rate was 1.0 mL/min. Results Hyaluronic acid could decrease the contents of C4S and C6S in rabbit joint synovial fluid. Conclusion The intra-articular injection of hyaluronic acid can reduce the degradation of aggrecan and/or enhance the synthesis of aggrecan in the joint tissues of rabbit osteoarthritis, and maintain the normal metabolism of articular cartilage.

  9. Optimization of transport media for human chondrocytes

    International Nuclear Information System (INIS)

    Full text: Autologous chondrocytes transplantation is a method used in treatment of cartilage defects in joints. Small fragments of patient healthy cartilage are removed and sent to a laboratory or tissue bank for cultivating chondrocytes. Obtained cells are reimplanted into areas of damaged cartilage. Since the transport of cartilage from a recovery site to a cell culture laboratory may be extended, it is very important to optimize the cartilage storage conditions in order to provide specimens with the best cell viability. Fresh human cartilage is stored in Ringer's solution or in normal saline at 4 degree C. Supplements such as hyaluronic acid and glucosamine have been shown to have chondroprotective effects. The aim of this experiment was to evaluate potential new storage media for improving chondrocytes viability. Cartilage fragments were harvested from fresh human femoral condyles. Cartilage samples from each condyle were separately stored at 4 degree C in: normal saline, Ringer solution, normal saline amended with hyaluronic acid and normal saline amended with glucosamine. The cartilage from each donor for each storage method was assayed for viability by MTT reduction assay on the day of recovery and after duration of one, two, three, six, twelve, and twenty-one days. Chondrocytes viability decreased with time in all media except for normal saline amended with glucosamine. The decline in chondrocytes viability was especially distinct for samples maintained in normal saline amended with hyaluronic acid when compared with standard media (normal saline and Ringer solution). In contrast, chondrocytes viability remained high for the whole duration of the experiment in samples maintained in normal saline amended with glucosamine. This finding suggests that the glucosamine supplementation of normal saline reduces the decline in chondrocytes viability and consequently extends the acceptable storage period of cartilage specimens. Further investigations are needed to

  10. Molecular analysis of chondrocytes cultured in agarose in response to dynamic compression

    Directory of Open Access Journals (Sweden)

    Mallein-Gerin Frédéric

    2008-09-01

    Full Text Available Abstract Background Articular cartilage is exposed to high mechanical loads under normal physiological conditions and articular chondrocytes regulate the composition of cartilaginous matrix, in response to mechanical signals. However, the intracellular pathways involved in mechanotransduction are still being defined. Using the well-characterized chondrocyte/agarose model system and dynamic compression, we report protocols for preparing and characterizing constructs of murine chondrocytes and agarose, and analyzing the effect of compression on steady-state level of mRNA by RT-PCR, gene transcription by gene reporter assay, and phosphorylation state of signalling molecules by Western-blotting. The mouse model is of particular interest because of the availability of a large choice of bio-molecular tools suitable to study it, as well as genetically modified mice. Results Chondrocytes cultured in agarose for one week were surrounded by a newly synthesized pericellular matrix, as revealed by immunohistochemistry prior to compression experiments. This observation indicates that this model system is suitable to study the role of matrix molecules and trans-membrane receptors in cellular responsiveness to mechanical stress. The chondrocyte/agarose constructs were then submitted to dynamic compression with FX-4000C™ Flexercell® Compression Plus™ System (Flexcell. After clearing proteins off agarose, Western-blotting analysis showed transient activation of Mitogen-activated protein kinases (MAPK in response to dynamic compression. After assessment by capillary electrophoresis of the quality of RNA extracted from agarose, steady-state levels of mRNA expression was measured by real time PCR. We observed an up-regulation of cFos and cJun mRNA levels as a response to compression, in accordance with the mechanosensitive character observed for these two genes in other studies using cartilage explants submitted to compression. To explore further the

  11. The Effects of Extracellular Matrix on Tissue Engineering Construction of Cartilage in Vitro

    Institute of Scientific and Technical Information of China (English)

    YU Li; LI Fa-tao; TANG Ming-qiao; YAN Wei-qun

    2006-01-01

    The effects of various cartilage extracellular matrix on the construction of rabbit growth plate cartilage tissue in vitro were studied. The results show that collagen, proteoglycan and hyaluronic acid can promote the growth of cultured chondrocytes but the effects of various cartilage extracellular matrix(ECM)on chondrocyte differentiation are different. Collagen can promote the hypertrophy of chondrocytes while proteoglycan and hyaluronic acid inhibit the transition of mature chondrocytes into hypertrophied chondrocytes.

  12. Effects of anti-arthritic drugs on proteoglycan synthesis by equine cartilage.

    Science.gov (United States)

    Frean, S P; Cambridge, H; Lees, P

    2002-08-01

    The concentration-effect relationships of phenylbutazone, indomethacin, betamethasone, pentosan polysulphate (PPS) and polysulphated glycosaminoglycan (PSGAG), on proteoglycan synthesis by equine cultured chondrocytes grown in monolayers, and articular cartilage explants were measured. The effect of PSGAG on interleukin-1beta induced suppression of proteogycan synthesis was also investigated. Proteoglycan synthesis was measured by scintillation assay of radiolabelled sulphate (35SO4) incorporation. Polysulphated glycosaminoglycan and PPS stimulated proteoglycan synthesis in chondrocyte monolayers in a concentration-related manner with maximal effects being achieved at a concentration of 10 microg/mL. Polysulphated glycosaminoglycan reversed the concentration-related suppression of proteoglycan synthesis induced by interleukin-1beta. Neither PSGAG nor PPS exerted significant effects on radiolabel incorporation in cartilage explants. Betamethasone suppressed proteoglycan synthesis by both chondrocytes and explants at high concentrations (0.1-100 microg/mL), but the effect was not concentration-related. At low concentrations (0.001-0.05 microg/mL) betamethasone neither increased nor decreased proteoglycan synthesis. Phenylbutazone and indomethacin increased radiolabel incorporation in chondrocyte cultures but not in cartilage explants at low (0.1, 1 and 10 microg/mL), but not at high (20 and 100 microg/mL) concentrations. These findings may be relevant to the clinical use of these drugs in the treatment of equine disease. PMID:12213118

  13. Extracorporeal shockwave therapy promotes chondrogenesis in cartilage tissue engineering: A hypothesis based on previous evidence.

    Science.gov (United States)

    Ji, Qiaodan; He, Chengqi

    2016-06-01

    The dearth of intrinsic regenerative capacity of articular cartilage makes it a challenge to deal with the cartilage defects. Among all the recommended clinical options, cartilage tissue engineering (CTE) which is highlighted of dominant features and less drawbacks for functional cartilage restoration, has been emphasized recently. Shock waves, a mode of therapeutic mechanical forces, utilized in extracorporeal shockwave therapy (ESWT), is hypothesized to enhance proliferation, chondrogenic differentiation, and cartilage extracellular matrix production of target cells seeded on bioactive scaffolds. The hypothesis is firstly based on cellular mechanotransduction by which cells convent the shockwave mechanical signals into biochemical responses via integrins, iron channels, cytoskeletal filaments, growth factor receptors and nuclei. Secondly, by modulating gene expression and up-regulating the release of various growth factors which are of vital importance in three-dimensional cartilage culture environment, ESWT holds a promising potential to favor the cell sources (e.g. chondrocytes and stem cells) to mimic the optimal functional cartilage. In all, on the basis of cellular mechanotransduction and previous evidence, the hypothesis is developed to support the beneficial effects of ESWT on chondrogenesis in CTE. If this hypothesis is confirmed, shockwaves may allow a better success in combination with other stimulating factors for cartilage repair. There is a paucity of studies investigating the assistant role of shockwave stimulation in CTE. Further research is required to elucidate the mechanisms, and explore effectiveness and appropriate protocols of this novel stimulative factor in cartilage tissue engineering. PMID:27142133

  14. Lesiones del cartílago articular de la rodilla en zona de carga. Artroscopia en 120 pacientes: Arthroscopy in 120 patients Lesions of the articular cartilage of the knee in a burden zone

    Directory of Open Access Journals (Sweden)

    Guillermo Reyes Chirino

    2005-03-01

    Full Text Available Se realizó un estudio retrospectivo en el Hospital Universitario "Abel Santamaría Cuadrado" de Pinar del Río en el periodo de enero/1999 a enero/2003 en 120 pacientes atendidos en el servicio de Ortopedia y Traumatología que presentaron lesiones del cartílago articular de las rodillas en zonas de carga de peso, tratados por cirugía artroscópica; con el objetivo de evaluar los factores que influyeron en la evolución de estos pacientes. De la muestra solo el 13.3 % fueron excelentes, el 35 % se evaluaron de bien, mientras el 38.3 % fueron regular y el 13.3 % con malos resultados. El peso corporal, las deformidades angulares de las rodillas, otras lesiones mecánicas asociadas, el estado de la masa muscular y la extensión y profundidad de las lesiones cartilaginosas influyeron notablemente en la evolución de estos pacientes según nuestros resultados así como la edad y el sexo.A retrospective study is performed at Abel Santamaría Cuadrado Hospital in Pinar del Río from January 1999 to January 2003 in 120 patients assisted in the Service of Orthopedics and Traumatology who presented with lesions in the articular cartilage of the knee in weight load areas, managed with asthroscopic surgery, in order to evaluate the factor which influenced the progress of these patients. Out of the sample, only 13.3 % was excellent, 35 % was good, whereas 38.3 % was not good and 13.3 % was poor. Body weight, knee angular deformities, other related mechanic lesions significantly influenced the progress of these patients, according to our results as well as age and sex.

  15. The Results of Fetal Chondrocytes Transplantation in Patients with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Natalya Krivoruchko

    2014-12-01

    Full Text Available Introduction. Nowadays anti-inflammatory and immunosuppressive therapy has significantly improved the quality of life and prognosis of rheumatoid arthritis (RA. Nevertheless, there are still many patients with progressive rheumatoid inflammation, resulting in the destruction of joints. Cell therapy seems like a promising direction in rheumatology. The aim of our research was to evaluate the efficacy of fetal chondrocyte transplantation in patients with RA.Methods. We examined 60 patients with rheumatoid arthritis (I - III stages between 20 and 63 years of age. They were divided into 2 groups: the first group underwent the fetal chondrocytes transplantation (n = 40, and the second was a control group who got conservative therapy (n = 20. Donor cells were taken from the chondrogenic layer of the humerus or femur heads and hip condyles of human embryos in gestation for 17-20 weeks. A suspension of fetal chondrocytes injected into affected areas of the articular surfaces under X-ray control. Cell viability was determined before the injection. Efficacy of the therapy was assessed by clinical, instrumental, and laboratory tests. This clinical trial was allowed by The Ministry of Public Health and Ethics Committee. All of our patients gave informed consent for the fetal chondrocytes transplantation.Results. Evaluation of the clinical manifestations of RA in the first group of patients showed 3.7 times decrease in pain and 1.6 times relief of synovitis. Complete reduction of contracture was observed in 82% of patients in the first group. Morphometric changes in X-ray demonstrated inhibition of the destruction in articular cartilage and surfaces of bones after transplantation of fetal chondrocytes. The dynamics of morphological changes in synovium showed 2.5 times reduction of the inflammatory reaction. Transplantation of fetal chondrocytes led to a significant reduction in ESR, CRP, fibrinogen , γ-globulin after a period of 12 months (p < 0

  16. Influence of intra-articular administration of trichostatin a on autologous osteochondral transplantation in a rabbit model.

    Science.gov (United States)

    Hou, Huacheng; Zheng, Ke; Wang, Guanghu; Ikegawa, Shiro; Zheng, Minghao; Gao, Xiang; Qin, Jinzhong; Teng, Huajian; Jiang, Qing

    2015-01-01

    Autologous osteochondral transplantation (AOT) is a method for articular cartilage repair. However, several disadvantages of this method have been reported, such as transplanted cartilage degeneration and the lack of a connection between the grafted and adjacent cartilage tissues. To evaluate the effect of intra-articular administration of trichostatin A (TSA) on AOT, we conducted a case control study in a rabbit model. International Cartilage Repair Society (ICRS) macroscopic scores, the modified O'Driscoll histology scores, and real-time PCR were utilized to evaluate the results. At 4 weeks, both macroscopic and histological assessments showed that there was no significant difference between the TSA and control groups. However, the mean macroscopic and histological scores for the TSA-treated group were significantly higher than the scores for the control group at 12 weeks. TSA was shown to directly reduce collagen type II (COL2), aggrecan, matrix metalloproteinase (MMP), and a disintegrin and metalloproteinase domain with thrombospondin motifs 5 (ADAMTS-5) expression and to simultaneously repress the upregulation of MMP-3, MMP-9, and MMP-13 levels induced by interleukin 1β (IL-1β) in chondrocytes. In conclusion, TSA protects AOT grafts from degeneration, which may provide a benefit in the repair of articular cartilage injury. PMID:25866784

  17. Influence of Intra-Articular Administration of Trichostatin A on Autologous Osteochondral Transplantation in a Rabbit Model

    Directory of Open Access Journals (Sweden)

    Huacheng Hou

    2015-01-01

    Full Text Available Autologous osteochondral transplantation (AOT is a method for articular cartilage repair. However, several disadvantages of this method have been reported, such as transplanted cartilage degeneration and the lack of a connection between the grafted and adjacent cartilage tissues. To evaluate the effect of intra-articular administration of trichostatin A (TSA on AOT, we conducted a case control study in a rabbit model. International Cartilage Repair Society (ICRS macroscopic scores, the modified O’Driscoll histology scores, and real-time PCR were utilized to evaluate the results. At 4 weeks, both macroscopic and histological assessments showed that there was no significant difference between the TSA and control groups. However, the mean macroscopic and histological scores for the TSA-treated group were significantly higher than the scores for the control group at 12 weeks. TSA was shown to directly reduce collagen type II (COL2, aggrecan, matrix metalloproteinase (MMP, and a disintegrin and metalloproteinase domain with thrombospondin motifs 5 (ADAMTS-5 expression and to simultaneously repress the upregulation of MMP-3, MMP-9, and MMP-13 levels induced by interleukin 1β (IL-1β in chondrocytes. In conclusion, TSA protects AOT grafts from degeneration, which may provide a benefit in the repair of articular cartilage injury.

  18. ECHO: the executable chondrocyte

    NARCIS (Netherlands)

    Scholma, J.; Schivo, S.; Kerkhofs, J.; Langerak, R.; Karperien, M.; Pol, van de J.; Geris, L.; Post, J.N.

    2014-01-01

    Introduction: We recently presented ANIMO (Analysis of Networks with Interactive Modeling), a software tool for modeling dynamic molecular networks for use by biologists [1, 2]. We used ANIMO to generate a computational model of articular cartilage. Materials and methods: Based on a largescale lite

  19. Remobilization causes site-specific cyst formation in immobilization-induced knee cartilage degeneration in an immobilized rat model.

    Science.gov (United States)

    Nagai, Momoko; Ito, Akira; Tajino, Junichi; Iijima, Hirotaka; Yamaguchi, Shoki; Zhang, Xiangkai; Aoyama, Tomoki; Kuroki, Hiroshi

    2016-06-01

    An understanding of the articular cartilage degenerative process is necessary for the prevention and treatment of joint disease. The present study aimed to examine how long-term immobilization-induced cartilage degeneration is aggravated by remobilization. Sixty 8-week-old male Wistar rats were used in this study. The unilateral knee joint was immobilized using an external fixator for 8 weeks. The rats were killed at 0 and 3 days, and at 1, 2, 4 and 8 weeks after removing the fixator. After the rats were killed, the maximum knee extension angles were measured. Histological sections at the medial mid-condylar region (non-contact, transitional and contact regions of the femur and tibia) were prepared and scored. The cartilage thickness and number of chondrocytes were measured, and CD44 and Col2-3/4c expression levels were assessed immunohistochemically. The histological assessment revealed progressive aggravation of cartilage degeneration in the transitional region, with a decreased number of chondrocytes and CD44-positive chondrocytes as well as poor scoring over time, particularly in the tibia. Cyst formation was confirmed in the transitional region of the tibia at 8 weeks post-remobilization. The cartilage thickness in the transitional region was thicker than that in the contact region, particularly in the tibia. Col2-3/4c expression was observed in the non-contact and transitional regions, and the knee extension angle was recovered. In conclusion, immobilization-induced cartilage degeneration was aggravated by remobilization over time in the transitional region, followed by observations of a decreased number of chondrocytes and morphological disparity between different cartilage regions. PMID:26989984

  20. Efficient, Low-Cost Nucleofection of Passaged Chondrocytes.

    Science.gov (United States)

    Parreno, Justin; Delve, Elizabeth; Andrejevic, Katarina; Paez-Parent, Sabrina; Wu, Po-Han; Kandel, Rita

    2016-01-01

    Nucleofection of chondrocytes has been shown to be an adequate method of transfection. Using Amaxa's nucleofection system, transfection efficiencies up to 89% were achievable for vector (pmaxGFP) and 98% for siRNA (siGLO) into passaged chondrocytes. However, such methods rely on costly commercial kits with proprietary reagents limiting its use in basic science labs and in clinical translation. Bovine-passaged chondrocytes were plated in serum reduced media conditionsand then nucleofected using various in laboratory-produced buffers. Cell attachment, confluency, viability, and transfection efficiency was assessed following nucleofection. For each parameter the buffers were scored and a final rank for each buffer was determined. Buffer denoted as 1M resulted in no significant difference for cell attachment, confluency, and viability as compared to non-nucleofected controls. Nucleofection in 1M buffer, in the absence of DNA vectors, resulted in increased col2, ki67, ccnd1 mRNA levels, and decreased col1 mRNA levels at 4 days of culture. Flow cytometry revealed that the transfection efficiency of 1M buffer was comparable to that obtained using the Amaxa commercial kit. siRNA designed against lamin A/C resulted in an average reduction of lamin A and C proteins to 19% and 8% of control levels, respectively. This study identifies a cost-effective, efficient method of nonviral nucleofection of bovine-passaged chondrocytes using known buffer formulations. Human-passaged chondrocytes could also be successfully nucleofected in 1M buffer. Thus this method should facilitate cost-efficient gene targeting of cells used for articular cartilage repair in a research setting. PMID:26958320

  1. Doublecortin May Play a Role in Defining Chondrocyte Phenotype

    Directory of Open Access Journals (Sweden)

    Dongxia Ge

    2014-04-01

    Full Text Available Embryonic development of articular cartilage has not been well understood and the role of doublecortin (DCX in determination of chondrocyte phenotype is unknown. Here, we use a DCX promoter-driven eGFP reporter mouse model to study the dynamic gene expression profiles in mouse embryonic handplates at E12.5 to E13.5 when the condensed mesenchymal cells differentiate into either endochondral chondrocytes or joint interzone cells. Illumina microarray analysis identified a variety of genes that were expressed differentially in the different regions of mouse handplate. The unique expression patterns of many genes were revealed. Cytl1 and 3110032G18RIK were highly expressed in the proximal region of E12.5 handplate and the carpal region of E13.5 handplate, whereas Olfr538, Kctd15, and Cited1 were highly expressed in the distal region of E12.5 and the metacarpal region of E13.5 handplates. There was an increasing gradient of Hrc expression in the proximal to distal direction in E13.5 handplate. Furthermore, when human DCX protein was expressed in human adipose stem cells, collagen II was decreased while aggrecan, matrilin 2, and GDF5 were increased during the 14-day pellet culture. These findings suggest that DCX may play a role in defining chondrocyte phenotype.

  2. Development and potential of a biomimetic chitosan/type Ⅱ collagen scaffold for cartilage tissue engineering

    Institute of Scientific and Technical Information of China (English)

    SHI De-hai; CAI Dao-zhang; ZHOU Chang-ren; RONG Li-min; WANG Kun; XU Yi-chun

    2005-01-01

    Background Damaged articular cartilage has very limited capacity for spontaneous healing. Tissue engineering provides a new hope for functional cartilage repair. Creation of an appropriate cell carrier is one of the critical steps for successful tissue engineering. With the supposition that a biomimetic construct might promise to generate better effects, we developed a novel composite scaffold and investigated its potential for cartilage tissue engineering. Methods Chitosan of 88% deacetylation was prepared via a modified base reaction procedure. A freeze-drying process was employed to fabricate a three-dimensional composite scaffold consisting of chitosan and type Ⅱcollagen. The scaffold was treated with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide. Ultrastructure and tensile strength of the matrix were carried out to assess its physico-chemical properties. After subcutaneous implantation in rabbits, its in vivo biocompatibility and degradability of the scaffold were determined. Its capacity to sustain chondrocyte growth and biosynthesis was evaluated through cell-scaffold co-culture in vitro. Results The fabricated composite matrix was porous and sponge-like with interconnected pores measuring from 100-250 μm in diameter. After cross-linking, the scaffold displayed enhanced tensile strength. Subcutaneous implantation results indicated the composite matrix was biocompatible and biodegradable. In intro cell-scaffold culture showed the scaffold sustaine