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OBJECTIVE: The etiology of osteoarthritis (OA) is unknown, however, there appears to be a significant contribution from genetics. We have identified recombinant inbred strains of mice derived from LG/J (large) and SM/J (small) strains that vary significantly in their ability to repair articular cartilage and susceptibility to post-traumatic OA due to their genetic composition. Here, we report cartilage repair phenotypes in the same strains of mice in which OA susceptibility was analyzed previously, and determine the genetic correlations between phenotypes. DESIGN: We used 12 recombinant inbred strains, including the parental strains, to test three phenotypes: ear-wound healing (n = 263), knee articular cartilage repair (n = 131), and post-traumatic OA (n = 53) induced by the surgical destabilization of the medial meniscus (DMM). Genetic correlations between various traits were calculated as Pearson's correlation coefficients of strain means. RESULTS: We found a significant positive correlation between ear-wound healing and articular cartilage regeneration (r = 0.71; P = 0.005). We observed a strong inverse correlation between articular cartilage regeneration and susceptibility to OA based on maximum (r = -0.54; P = 0.036) and summed Osteoarthritis Research Society International (OARSI) scores (r = -0.56; P = 0.028). Synovitis was not significantly correlated with articular cartilage regeneration but was significantly positively correlated with maximum (r = 0.63; P = 0.014) and summed (r = 0.70; P = 0.005) OARSI scores. Ectopic calcification was significantly positively correlated with articular cartilage regeneration (r = 0.59; P = 0.021). CONCLUSIONS: Using recombinant inbred strains, our study allows, for the first time, the measurement of genetic correlations of regeneration phenotypes with degeneration phenotypes, characteristic of OA (cartilage degeneration, synovitis). We demonstrate that OA is positively correlated with synovitis and inversely correlated with the ability to repair cartilage. These results suggest an addition to the risk paradigm for OA from a focus on degeneration to regeneration.
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Cartílago Articular/lesiones , Oído Externo/lesiones , Osteoartritis de la Rodilla/genética , Regeneración/genética , Cicatrización de Heridas/genética , Animales , Cartílago Articular/fisiología , Modelos Animales de Enfermedad , Cartílago Auricular/lesiones , Cartílago Auricular/fisiología , Oído Externo/fisiología , Meniscos Tibiales/cirugía , Ratones , Ratones Endogámicos , Osteoartritis de la Rodilla/fisiopatología , Fenotipo , Regeneración/fisiología , Cicatrización de Heridas/fisiologíaRESUMEN
OBJECTIVE: Anterior cruciate ligament (ACL) injury initiates a cascade of events often leading to osteoarthritis (OA). ACL reconstruction does not alter the course of OA, suggesting that heightened OA risk is likely due to factors in addition to the joint instability. We showed that torn ACL remnants express periostin (POSTN) in the acute phase of injury. Considering that ACL injury predisposes to OA and that POSTN is associated with cartilage metabolism, we hypothesize that ACL injury affects chondrocytes via POSTN. DESIGN: Cartilage was obtained from osteoarthritic patients and ACL remnants were collected from patients undergoing ACL reconstruction. Crosstalk between ACL remnants and chondrocytes was studied in a transwell co-culture system. Expression of POSTN and other anabolic and catabolic genes was assessed via real-time polymerase chain reaction (PCR). Immunostaining for periostin was performed in human and mouse cartilage. The impact of exogenous periostin and siRNA-mediated ablation of periostin on matrix metabolism and cell migration was examined. Furthermore, the effect of anabolic (transforming growth factor beta 1 [TGF-ß1]) and catabolic (interleukin 1 beta [IL-1ß]) factors on POSTN expression was investigated. RESULTS: ACL remnants induced expression of POSTN, MMP13 and ADAMTS4. Periostin levels were significantly higher in osteoarthritic compared to normal cartilage. Exogenous periostin induced MMP13 expression and cell migration, and repressed COL1A1 expression while POSTN knockdown inhibited expression of both anabolic and catabolic genes and impeded cell migration. TGF-ß1 and IL-1ß treatment did not alter POSTN expression but influenced chondrocyte metabolism as determined by quantification of anabolic and catabolic genes via real-time PCR. CONCLUSIONS: ACL remnants can exert paracrine effects on cartilage, altering cellular homeostasis. Over time, this metabolic imbalance could contribute to OA development.
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Lesiones del Ligamento Cruzado Anterior/complicaciones , Cartílago Articular/metabolismo , Moléculas de Adhesión Celular/biosíntesis , Condrocitos/metabolismo , Osteoartritis de la Rodilla/etiología , Lesiones del Ligamento Cruzado Anterior/metabolismo , Lesiones del Ligamento Cruzado Anterior/patología , Cartílago Articular/patología , Moléculas de Adhesión Celular/genética , Células Cultivadas , Condrocitos/patología , Regulación de la Expresión Génica , Humanos , Osteoartritis de la Rodilla/metabolismo , Osteoartritis de la Rodilla/patología , ARN/genéticaRESUMEN
OBJECTIVE: To assess the impact of osteoarthritis (OA) on the meniscus by comparing transcripts and biological processes in the meniscus between patients with and without OA. DESIGN: RNA microarrays were used to identify transcripts differentially expressed (DE) in meniscus obtained from 12 OA and 12 non-OA patients. The non-OA specimens were obtained at the time of arthroscopic partial meniscectomy. Real-time PCR was performed on selected transcripts. Biological processes and gene-networking was examined computationally. Transcriptome signatures were mapped with 37 OA-related transcripts to evaluate how meniscus gene expression relates to that of OA cartilage. RESULTS: We identified 168 transcripts significantly DE between OA (75 elevated, 93 repressed) and non-OA samples (≥1.5-fold). Among these, CSN1S1, COL10A1, WIF1, and SPARCL1 were the most prominent transcripts elevated in OA meniscus, POSTN and VEGFA were most highly repressed in OA meniscus. Transcripts elevated in OA meniscus represented response to external stimuli, cell migration and cell localization while those repressed in OA meniscus represented histone deacetylase activity (related to epigenetics) and skeletal development. Numerous long non-coding RNAs (lncRNAs) were DE between the two groups. When segregated by OA-related transcripts, two distinct clustering patterns appeared: OA meniscus appeared to be more inflammatory while non-OA meniscus exhibited a "repair" phenotype. CONCLUSIONS: Numerous transcripts with potential relevance to the pathogenesis of OA are DE in OA and non-OA meniscus. These data suggest an involvement of epigenetically regulated histone deacetylation in meniscus tears as well as expression of lncRNAs. Patient clustering based on transcripts related to OA in articular cartilage confirmed distinct phenotypes between injured (non-OA) and OA meniscus.
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Perfilación de la Expresión Génica , Menisco/metabolismo , Osteoartritis/metabolismo , Anciano , Estudios de Casos y Controles , Epigénesis Genética , Femenino , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Reacción en Cadena en Tiempo Real de la Polimerasa , TranscriptomaRESUMEN
Animal models of osteoarthritis (OA) are essential tools for investigating the development of the disease on a more rapid timeline than human OA. Mice are particularly useful due to the plethora of genetically modified or inbred mouse strains available. The majority of available mouse models of OA use a joint injury or other acute insult to initiate joint degeneration, representing post-traumatic osteoarthritis (PTOA). However, no consensus exists on which injury methods are most translatable to human OA. Currently, surgical injury methods are most commonly used for studies of OA in mice; however, these methods may have confounding effects due to the surgical/invasive injury procedure itself, rather than the targeted joint injury. Non-invasive injury methods avoid this complication by mechanically inducing a joint injury externally, without breaking the skin or disrupting the joint. In this regard, non-invasive injury models may be crucial for investigating early adaptive processes initiated at the time of injury, and may be more representative of human OA in which injury is induced mechanically. A small number of non-invasive mouse models of PTOA have been described within the last few years, including intra-articular fracture of tibial subchondral bone, cyclic tibial compression loading of articular cartilage, and anterior cruciate ligament (ACL) rupture via tibial compression overload. This review describes the methods used to induce joint injury in each of these non-invasive models, and presents the findings of studies utilizing these models. Altogether, these non-invasive mouse models represent a unique and important spectrum of animal models for studying different aspects of PTOA.
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Lesiones del Ligamento Cruzado Anterior , Cartílago Articular/lesiones , Modelos Animales de Enfermedad , Traumatismos de la Rodilla/complicaciones , Ratones , Osteoartritis de la Rodilla/etiología , Tibia/lesiones , Animales , Fracturas Intraarticulares , Fracturas de la TibiaRESUMEN
OBJECTIVE: C-C chemokine receptor type 5 (CCR5) has been implicated in rheumatoid arthritis and several inflammatory diseases, where its blockade resulted in reduced joint destruction. However, its role in modulating cartilage and bone changes in post-traumatic osteoarthritis (OA) has not yet been investigated. In this study, we investigated changes in articular cartilage, synovium and bone in a post-traumatic OA model using CCR5-deficient (CCR5(-/-)) mice. METHOD: Destabilization of the medial meniscus (DMM) was performed on the right knee of 10-week old CCR5(-/-) and C57BL/6J wild-type (WT) mice to induce post-traumatic OA. The contralateral left knee served as sham-operated control. Knee joints were analyzed at 4-, 8- and 12-weeks after surgery to evaluate cartilage degeneration and synovitis by histology, and bone changes via micro-CT. RESULTS: Our findings showed that CCR5(-/-) mice exhibited significantly less cartilage degeneration than WT mice at 8- and 12-weeks post-surgery. CCR5(-/-) mice showed some altered bone parameters 18- and 22-weeks of age, but body size and weight were not affected. The effect of CCR5-ablation was insignificant at all time points post-surgery for synovitis and for bone parameters such as bone volume/total volume, connectivity density index (CDI), structure model index (SMI), subchondral bone plate thickness, and trabecular bone number, thickness and spacing. CONCLUSION: These findings suggest that CCR5(-/-) mice developed less cartilage degeneration, which may indicate a potential protective role of CCR5-ablation in cartilage homeostasis. There were no differences in bone or synovial response to surgery suggesting that CCR5 functions primarily in cartilage during the development of post-traumatic OA.
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Cartílago Articular/patología , Fémur/diagnóstico por imagen , Osteoartritis de la Rodilla/genética , Receptores CCR5/genética , Membrana Sinovial/patología , Tibia/diagnóstico por imagen , Lesiones de Menisco Tibial , Animales , Modelos Animales de Enfermedad , Fémur/patología , Traumatismos de la Rodilla/complicaciones , Ratones , Ratones Noqueados , Osteoartritis de la Rodilla/diagnóstico , Osteoartritis de la Rodilla/etiología , Tibia/patología , Microtomografía por Rayos XRESUMEN
Osteoarthritis affects the whole joint structure with progressive changes in cartilage, menisci, ligaments and subchondral bone, and synovial inflammation. Biomarkers are being developed to quantify joint remodelling and disease progression. This article was prepared following a working meeting of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis convened to discuss the value of biochemical markers of matrix metabolism in drug development in osteoarthritis. The best candidates are generally molecules or molecular fragments present in cartilage, bone or synovium and may be specific to one type of joint tissue or common to them all. Many currently investigated biomarkers are associated with collagen metabolism in cartilage or bone, or aggrecan metabolism in cartilage. Other biomarkers are related to non-collagenous proteins, inflammation and/or fibrosis. Biomarkers in osteoarthritis can be categorised using the burden of disease, investigative, prognostic, efficacy of intervention, diagnostic and safety classification. There are a number of promising candidates, notably urinary C-terminal telopeptide of collagen type II and serum cartilage oligomeric protein, although none is sufficiently discriminating to differentiate between individual patients and controls (diagnostic) or between patients with different disease severities (burden of disease), predict prognosis in individuals with or without osteoarthritis (prognostic) or perform so consistently that it could function as a surrogate outcome in clinical trials (efficacy of intervention). Future avenues for research include exploration of underlying mechanisms of disease and development of new biomarkers; technological development; the 'omics' (genomics, metabolomics, proteomics and lipidomics); design of aggregate scores combining a panel of biomarkers and/or imaging markers into single diagnostic algorithms; and investigation into the relationship between biomarkers and prognosis.
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OBJECTIVE: Joint trauma can lead to a spectrum of acute lesions, including cartilage degradation, ligament or meniscus tears, and synovitis, all potentially associated with osteoarthritis (OA). This study was undertaken to generate and validate a murine model of knee joint trauma following noninvasive controlled injurious compression in vivo. METHODS: The right knees of 8-week-old mice were placed in a hyperflexed position and subjected to compressive joint loading at 1 of 3 peak forces (3N, 6N, or 9N) for 60 cycles in a single loading period and harvested on days 5, 9, and 14 after loading (n = 3-5 for each time point and for each loading). The left knees were not loaded and were used as the contralateral control. Histologic, immunohistochemical, and enzyme-linked immunosorbent assay analyses were performed to evaluate acute pathologic features in chondrocyte viability, cartilage matrix metabolism, synovial reaction, and serum cartilage oligomeric matrix protein (COMP) levels. RESULTS: Acute joint pathology was associated with increased injurious loads. All loading regimens induced chondrocyte apoptosis, cartilage matrix degradation, disruption of cartilage collagen fibril arrangement, and increased levels of serum COMP. We also observed that 6N loading induced mild synovitis by day 5, whereas at 9N, with tearing of the anterior cruciate ligament, severe posttraumatic synovitis and ectopic cartilage formation were observed. CONCLUSION: We have established a murine model of knee joint trauma with different degrees of overloading in vivo. Our results suggest that immediate therapies particularly targeted to apoptosis and synovial cell proliferation could affect the acute posttraumatic reaction to potentially limit chronic consequences and OA.
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Proteína de la Matriz Oligomérica del Cartílago/metabolismo , Traumatismos de la Rodilla/metabolismo , Articulación de la Rodilla/metabolismo , Proteínas Matrilinas/metabolismo , Membrana Sinovial/metabolismo , Animales , Apoptosis , Proliferación Celular , Condrocitos/metabolismo , Condrocitos/patología , Traumatismos de la Rodilla/patología , Articulación de la Rodilla/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Membrana Sinovial/patología , Factores de Tiempo , Soporte de Peso/fisiologíaRESUMEN
Osteoarthritis affects the whole joint structure with progressive changes in cartilage, menisci, ligaments and subchondral bone, and synovial inflammation. Biomarkers are being developed to quantify joint remodelling and disease progression. This article was prepared following a working meeting of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis convened to discuss the value of biochemical markers of matrix metabolism in drug development in osteoarthritis. The best candidates are generally molecules or molecular fragments present in cartilage, bone or synovium and may be specific to one type of joint tissue or common to them all. Many currently investigated biomarkers are associated with collagen metabolism in cartilage or bone, or aggrecan metabolism in cartilage. Other biomarkers are related to non-collagenous proteins, inflammation and/or fibrosis. Biomarkers in osteoarthritis can be categorised using the burden of disease, investigative, prognostic, efficacy of intervention, diagnostic and safety classification. There are a number of promising candidates, notably urinary C-terminal telopeptide of collagen type II and serum cartilage oligomeric protein, although none is sufficiently discriminating to differentiate between individual patients and controls (diagnostic) or between patients with different disease severities (burden of disease), predict prognosis in individuals with or without osteoarthritis (prognostic) or perform so consistently that it could function as a surrogate outcome in clinical trials (efficacy of intervention). Future avenues for research include exploration of underlying mechanisms of disease and development of new biomarkers; technological development; the 'omics' (genomics, metabolomics, proteomics and lipidomics); design of aggregate scores combining a panel of biomarkers and/or imaging markers into single diagnostic algorithms; and investigation into the relationship between biomarkers and prognosis.
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Biomarcadores/metabolismo , Osteoartritis/metabolismo , Cartílago Articular/metabolismo , Progresión de la Enfermedad , Humanos , Osteoartritis/patología , Membrana Sinovial/metabolismoRESUMEN
OBJECTIVE: Aging and obesity contribute to the initiation and progression of osteoarthritis with little information on their relation to gene expression in joint tissues, particularly the meniscus. Here, we test the hypothesis that patient age and body mass index (BMI) correlate with the expression of osteoarthritis- and obesity-related gene signatures in the meniscus. DESIGN: Meniscus was obtained from patients (N=68) undergoing arthroscopic partial meniscectomy. The mRNA expression of 24 osteoarthritis-related and 4 obesity-related genes in meniscus was assessed by quantitative real-time PCR. The relationship between gene expression and patient age and BMI was analyzed using Spearman's rank-order correlation. Hierarchical cluster dendrogram and heat map were generated to study inter-gene associations. RESULTS: Age was negatively correlated (P<0.05) with the expression of MMP-1 (r=-0.447), NFκB2 (r=-0.361), NFκBIA (r=-0.312), IκBA (r=-0.308), IL-8 (r=-0.305), ADAMTS-4 (r=-0.294), APLN (apelin) (r=-0.250) and IL-6 (r=-0.244). Similarly, BMI was negatively correlated with the expression of APLN (r=-0.328), ACAN (r=-0.268) and MMP-1 (r=-0.261). After adjusting for the correlation between age and BMI (r=0.310; P=0.008), the only independent effect of BMI on gene expression was for APLN (r=-0.272). However, age had an independent effect on the expression on ADAMTS-4 (r=-0.253), MMP-1 (r=-0.399), IL-8 (r=-0.327), COL1A1 (r=-0.287), NFκBIA (r=-0.278), NFκB2 (r=-0.312) and IκBA (r=-0.299). The gene correlation analysis identified four clusters of potentially relevant genes: transcription factors, matrix-degrading enzymes, cytokines and chemokines, and obesity genes. CONCLUSION: Age and BMI were negatively correlated with several osteoarthritis- and obesity-related genes. Although the bulk of these changes appeared to be driven by age, expression of APLN was related to BMI. Inter-gene correlation analysis implicated a common role for strongly correlated genes. Although age-related variations in gene expression appear to be more relevant than obesity-related differences for the role of the meniscus in osteoarthritis development, further investigation into the role of APLN in meniscus and joint health is warranted.
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Envejecimiento , Índice de Masa Corporal , Cartílago Articular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Meniscos Tibiales/metabolismo , Obesidad/metabolismo , Osteoartritis/metabolismo , Proteínas ADAM/metabolismo , Proteína ADAMTS4 , Adolescente , Adulto , Anciano , Envejecimiento/metabolismo , Apelina , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Proteínas I-kappa B/metabolismo , Interleucina-8/metabolismo , Masculino , Metaloproteinasa 1 de la Matriz/metabolismo , Persona de Mediana Edad , Inhibidor NF-kappaB alfa , Subunidad p52 de NF-kappa B/metabolismo , Obesidad/epidemiología , Obesidad/genética , Osteoartritis/epidemiología , Osteoartritis/genética , Procolágeno N-Endopeptidasa/metabolismo , Análisis por Matrices de Proteínas , Reacción en Cadena en Tiempo Real de la Polimerasa , Lesiones de Menisco Tibial , Estados Unidos/epidemiologíaRESUMEN
INTRODUCTION: Little evidence is available on the natural course of osteoarthritis (OA) development and the genes that protect and predispose individuals to it. This study was designed to compare strain-dependent development of OA and its association with tissue regeneration in mice. Two recombinant inbred lines LGXSM-6 and LGXSM-33 generated from LG/J and SM/J intercross were used. Previous studies indicated that LGXSM-6 can regenerate both articular cartilage and ear hole punch while LGXSM-33 cannot. METHODS: Transection of the medial meniscotibial ligament was performed on 10-week-old male mice to induce OA. Cartilage damage was analyzed by histology and bone morphology was evaluated using micro-computed tomography (CT). Ear punches were performed and evaluated by measurement of residual hole diameter. RESULTS: Cartilage analysis showed that LGXSM-33 developed a significantly higher grade of OA than LGXSM-6. Bone analysis showed that LGXSM-33 had substantial subchondral bone and trabecular bone thickening 8 weeks post-surgery, while LGXSM-6 showed bone loss over time. We also confirmed that LGXSM-6 can heal ear tissues significantly better than LGXSM-33. CONCLUSIONS: OA was found to be negatively correlated with the degree of tissue regeneration. LGXSM-33, a poor healer of ear tissues (and articular cartilage), developed more OA compared to LGXSM-6, which had better regenerative ability for ear tissues and articular cartilage. The phenotypic differences observed here are due to genetic differences further suggesting that similar sets of physiological processes and gene variants may mediate variation in OA development and tissue regeneration.
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Artritis Experimental/patología , Huesos/patología , Cartílago Articular/patología , Osteoartritis/patología , Animales , Artritis Experimental/diagnóstico por imagen , Artritis Experimental/genética , Artritis Experimental/fisiopatología , Huesos/diagnóstico por imagen , Cartílago Articular/fisiología , Oído Externo/lesiones , Oído Externo/fisiología , Predisposición Genética a la Enfermedad , Masculino , Ligamento Colateral Medial de la Rodilla/lesiones , Ratones , Ratones Endogámicos , Osteoartritis/diagnóstico por imagen , Osteoartritis/genética , Osteoartritis/fisiopatología , Regeneración/fisiología , Especificidad de la Especie , Cicatrización de Heridas/fisiología , Microtomografía por Rayos XRESUMEN
On November fourth and fifth 2010 a group of more than 100 international investigators gathered in Atlanta for the second Osteoarthritis (OA) Biomarkers Global Initiative workshop titled "Genetics and Genomics: New Targets in OA". The first workshop took place in April 2009 and focused on in vitro (soluble) biomarkers whilst the third and final workshop will take place in 2012 and will focus on imaging biomarkers. The OA Research Society International (OARSI) has organized the workshops. In addition to OARSI, the National Institute of Arthritis, Musculoskeletal and Skin Diseases, the Arthritis Foundation, Amgen, Genzyme, the American Orthopaedic Society for Sports Medicine and Pfizer sponsored the second meeting. It was clear from this meeting that experiments in the genetics, epigenetics and genomics of OA, are yielding valuable insights into the etiology of this heterogeneous disease but that much still needs to be learnt. Combining genetic insights with conventional biomarkers and imaging modalities may provide scientists with the enhanced tools to understand this complex disease. With those tools in hand, clinicians and industry can develop protocols to ultimately improve patient care.
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Investigación Biomédica , Osteoartritis/genética , Biomarcadores , Genómica/tendencias , HumanosRESUMEN
Osteoarthritis (OA) biomarkers that can measure and predict the full spectrum of disease progression and outcomes are needed, but few, if any, such biomarkers have been validated for this purpose. The Osteoarthritis Research Society International (OARSI) has organized an OA Biomarkers Global Initiative. As a part of this Initiative, three workshops have been planned to occur over the next 4 years to focus on identifying and removing obstacles to progress in the field and planning the way forward. In addition to OARSI, the National Institute of Arthritis, Musculoskeletal, and Skin Disease, the Arthritis Foundation, the Orthopaedic Research Society, and the American Orthopaedic Sports Medicine Society cosponsored the first meeting April 23-24, 2009. Organizers brought together thought and research leaders in the field, young investigators, biomarkers researchers with insights from other fields, clinical investigators with a responsibility for OA sample and resource management, funding agencies, and commercial entities with an interest in the commercial propagation as well as the application of markers in OA.
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Osteoartritis/clasificación , Biomarcadores/análisis , Investigación Biomédica/normas , Progresión de la Enfermedad , Humanos , Reproducibilidad de los ResultadosRESUMEN
This study has assessed the relative proportions of type I and II collagens and IIA procollagen in full depth biopsies of repair tissue in a large sample of patients treated with autologous chondrocyte implantation (ACI). Sixty five full depth biopsies were obtained from knees of 58 patients 8-60 months after treatment by ACI alone (n=55) or in combination with mosaicplasty (n=10). In addition articular cartilage was examined from eight individuals (aged 10-50) as controls. Morphology and semi-quantitative immunohistochemistry for collagen types I and II and procollagen IIA in the repair tissue were studied. Repair cartilage thickness was 2.89+/-1.5 mm and there was good basal integration between the repair cartilage, calcified cartilage and subchondral bone. Sixty five percent of the biopsies were predominantly fibrocartilage (mostly type I collagen and IIA procollagen), 15% were hyaline cartilage (mostly type II collagen), 17% were of mixed morphology and 3% were fibrous tissue (mostly type I collagen). Type II collagen and IIA procollagen were usually found in the lower regions near the bone and most type II collagen was present 30-60 months after treatment. The presence of type IIA procollagen in the repair tissue supports our hypothesis that this is indicative of a developing cartilage, with the ratio of type II collagen:procollagen IIA increasing from <2% in the first two years post-treatment to 30% three to five years after treatment. This suggests that cartilage repair tissue produced following ACI treatment, is likely to take some years to mature.
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Cartílago Articular/cirugía , Condrocitos/trasplante , Colágeno Tipo II/metabolismo , Colágeno Tipo I/metabolismo , Fibrocartílago/metabolismo , Técnicas para Inmunoenzimas/métodos , Adulto , Biomarcadores/metabolismo , Biopsia , Cartílago Articular/metabolismo , Cartílago Articular/patología , Trasplante de Células , Condrocitos/metabolismo , Fibrocartílago/patología , Técnica del Anticuerpo Fluorescente Directa , HumanosRESUMEN
OBJECTIVE: To provide a more complete picture of the effect of interleukin-1 beta (IL-1beta) on adult human articular chondrocyte gene expression, in contrast to the candidate gene approach. DESIGN: Chondrocytes from human knee cartilage were cultured in medium containing IL-1beta. Changes in gene expression were analyzed by microarray and reverse transcriptase-polymerase chain reaction analysis. The ability of transforming growth factor beta-1 (TGF-beta1), fibroblast growth factor (FGF)-18, and bone morphogenetic protein 2 (BMP-2) to alter the effects of IL-1beta was analyzed. Computational analysis of the promoter regions of differentially expressed genes for transcription factor binding motifs was performed. RESULTS: IL-1beta-treated human chondrocytes showed significant increases in the expression of granulocyte colony stimulating factor-3, endothelial leukocyte adhesion molecule 1 and leukemia inhibitory factor as well as for a large group of chemokines that include CXCL1, CXCL2, CXCL3, CXCL5, CXCL6, CXCL8, CCL2, CCL3, CCL4, CCL5, CCL8, CCL20, CCL3L1, CX3CL1 and the cytokine IL-6. As expected, the mRNA for matrix metalloproteinase (MMP)-13 and BMP-2 also increased while mRNA for the matrix genes COL2A1 and aggrecan was down-regulated. A subset of chemokines increased rapidly at very low levels of IL-1beta. The phenotype induced by IL-1beta was partially reversed by TGF-beta1, but not by BMP-2. In the presence of IL-1beta, FGF-18 increased expression of ADAMTS-4, aggrecan, BMP-2, COL2A1, CCL3, CCL4, CCL20, CXCL1, CXCL3, CXCL6, IL-1beta, IL-6, and IL-8 and decreased ADAMTS-5, MMP-13, CCL2, and CCL8. Computational analysis revealed a high likelihood that the most up-regulated chemokines are regulated by the transcription factors myocyte enhancer binding factor-3 (MEF-3), CCAAT/enhancer binding protein (C/EBP) and nuclear factor-kappa B (NF-kappaB). CONCLUSION: IL-1beta has a diverse effect on gene expression profile in human chondrocytes affecting matrix genes as well as chemokines and cytokines. TGF-beta1 has the ability to antagonize some of the phenotype induced by IL-1beta.
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Artritis/metabolismo , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Factores de Crecimiento de Fibroblastos/antagonistas & inhibidores , Interleucina-1beta/antagonistas & inhibidores , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Artritis/genética , Células Cultivadas , Quimiocinas/metabolismo , Quimiocinas/farmacología , Regulación de la Expresión Génica/genética , Humanos , Interleucina-1beta/farmacología , FN-kappa B/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Regulación hacia ArribaRESUMEN
OBJECTIVE: Oxidative stress occurs when the metabolic balance of a cell is disrupted through exposure to excess pro-oxidant. Whilst it is known that unregulated production or exposure to exogenous sources of pro-oxidants induces chondrocyte cell death and degrades matrix components in vitro, relatively little is known of the effects of pro-oxidants on articular cartilage in situ. The objective of this study was to determine if a single exposure to the pro-oxidant hydrogen peroxide (H(2)O(2)) induces a degenerative phenotype. METHODS: Articular cartilage explants were obtained from skeletally mature bovine steers and exposed to a single dose of hydrogen peroxide (0.1-1.0 mM) and cultured for up to 21 days. Cell death, and sulfated glycosaminoglycan loss into the medium and gene expression were quantitatively determined. Adoption of an abnormal chondrocyte phenotype was analyzed through the expression of 3B3(-), nitrotyrosine and procollagen type IIA epitopes in cartilage explants. RESULTS: Cell death occurred primarily at the surface zone of cartilage in a dose-dependent manner in H(2)O(2) treated explants, and supplementation of standard serum-free medium with insulin-selenium-transferrin significantly reduced cell death (>fourfold). Nitric oxide synthase-2 gene expression and proteoglycan loss increased in oxidant treated explants in a concentration-dependent manner. Antibody labeling to 3B3(-), procollagen type IIA and nitrotyrosine was present in all treated explants but absent in untreated explants. CONCLUSIONS: This study demonstrates that a single exposure to high levels of pro-oxidant causes the expression of genes and antibody epitopes that are associated with early degenerative changes observed in experimental osteoarthritis.
Asunto(s)
Cartílago Articular/metabolismo , Osteoartritis/metabolismo , Estrés Oxidativo/fisiología , Procolágeno/metabolismo , Animales , Biomarcadores/metabolismo , Cartílago Articular/citología , Cartílago Articular/efectos de los fármacos , Bovinos , Muerte Celular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Masculino , Técnicas de Cultivo de TejidosRESUMEN
OBJECTIVES: The 5-yr longitudinal study tested the hypothesis that serum and urinary markers of type II collagen metabolism would be associated with radiological progression of disease in patients with mild-to-moderate knee osteoarthritis (OA). METHODS: Synthesis of type IIA collagen and degradation of total type II collagen were assessed in 135 patients with mild-to-moderate knee OA over 5 yrs using serum concentration of the N-propeptide of collagen type IIA (PIIANP) and urinary excretion of crosslinked C-telopeptide (CTX-II), respectively. The markers were measured at baseline, 2, 3 and 5 yrs' follow-up corresponding to X-ray time points. Analysis of variance (ANOVA) was performed to determine longitudinal changes over 5 yrs in the biomarkers in all patients and between progressors and non-progressors. RESULTS: Complete X-ray progression data over 5 yrs, serum PIIANP and urinary CTX-II were available for 84/135 patients. There were 24 progressors and 60 non-progressors. Overall, over the 5-yr study period average PIIANP and CTX-II levels were higher in progressors compared with non-progressors (P < 0.05 for both, ANOVA). The patients with serum PIIANP in the highest quartile of 5-yr levels of PIIANP had a significantly higher risk of progression than the other patients [relative risk (95% CI): 3.2 (1.1-9.2)]. Increased levels of urinary CTX-II were also associated with a higher risk of progression with a relative risk (95% CI) of 3.4 (1.2-9.4) in patients with 5-yr levels above the median. The risk of progression was highest in patients with 5-yr levels of PIIANP in the highest quartile and/or CTX-II in the two highest quartiles with a relative risk (95% CI) of progression, 11.8 (2.5-54). CONCLUSIONS: The data presented here suggest that progression of knee OA is associated with alterations of systemic levels of biological markers of type II collagen metabolism. The data also suggest that the combined measurement of serum PIIANP and urinary CTX-II may be useful to identify patients with knee OA at increased risk of disease progression.
Asunto(s)
Colágeno Tipo II/metabolismo , Osteoartritis de la Rodilla/metabolismo , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Colágeno Tipo I/orina , Colágeno Tipo II/biosíntesis , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Dimensión del Dolor , Fragmentos de Péptidos/sangre , Péptidos/orina , Procolágeno/sangre , Radiografía , Índice de Severidad de la EnfermedadRESUMEN
While a great deal of information is available on the cellular and molecular biology of cartilage degradation, less is known about anabolism in normal cartilage and degenerating cartilage. A consistent amount of evidence is now available on the neo-synthesis of matrix molecules and enzymes in OA: the entire cell metabolism appears to be increased leading to the hypothesis that chondrocytes in OA are actually "activated". This chapter will focus on anabolic events that are now known to occur in articular cartilage. We will begin to view articular cartilage as a complex three-dimensional tissue in which local events may be different. We will also be interested in viewing the development of degenerative arthritis as a continuum from functionally normal tissue to degeneration.
Asunto(s)
Anabolizantes/metabolismo , Cartílago Articular/patología , Osteoartritis/metabolismo , Proteína Morfogenética Ósea 2 , Proteínas Morfogenéticas Óseas/metabolismo , Cartílago Articular/metabolismo , Condrocitos/metabolismo , Colágeno Tipo II/metabolismo , Humanos , Interleucina-1/metabolismo , Factor de Crecimiento Transformador beta/metabolismoRESUMEN
This study examines the age at which a femoral physeal failure ceased to occur in a mouse model of medial collateral ligament (MCL) testing. Biomechanical testing of the MCL with load to failure can result in physeal failure rather than MCL failure in skeletally immature animals. Failure mode depended significantly on age (p<0.05). Sixty percent of the knees tested at 4 months failed at the physis rather than at the ligament, whereas, only ten percent of the knees tested at 5 and 6 months failed at the physis. The mean ultimate force to failure for the specimens in which the failure occurred at the ligament was 8.1 N with a higher values for the right side versus the left (p<0.05). For the specimens in which the failure occurred at the physis, the mean ultimate force to failure was 11.2 N. We now consider that 5 month old mice are functionally skeletally mature and old enough to be tested biomechanically with few failures at the physis.