Caspase-1 Level in Synovial Fluid Is High in Patients with Spondyloarthropathy but Not in Patients with Gout

Activation of caspase-1 by NALP3 inflammasomes has been shown to be important in initiating acute gouty arthritis. The objectives of this study were to measure the levels of caspase-1 in synovial fluid in gout and various arthritides, and to elucidate the clinical significance of caspase-1 levels in synovial fluid. Caspase-1, IL-1beta, IL-18, and uric acid were measured in synovial fluid from 112 patients with gout and other arthritides, such as rheumatoid arthritis, osteoarthritis, and spondyloarthropathy. Caspase-1 in synovial fluid from patients with crystal-induced arthritis, inflammatory arthritis, osteoarthritis, and spondyloarthropathy was 35.9 +/- 86.7, 49.7 +/- 107.7, 2.1 +/- 7.0, and 152.6 +/- 155.7 pg/mL, respectively. The mean level and the frequency of high levels (> or =125 pg/mL) of caspase-1 in spondyloarthropathy were significantly higher than those in the other arthritides including gout. Caspase-1 was detectible in the synovial fluid of patients with the various arthritides. Contrary to our hypothesis, the caspase-1 level in the synovial fluid of patients with gout was not higher than in that of other arthritides. High levels of caspase-1 may be helpful in differentiating spondyloarthropathy from other arthritides.

Biomarkers for identifying the early phases of osteoarthritis secondary to medial patellar luxation in dogs

The levels of tartrate resistant acid phosphatase (TRAP), matrix metalloproteinase-2 (MMP-2), and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in synovial fluid (SF) and serum in cases of canine osteoarthritis (OA) were measured. OA was induced by a surgically-created medial patellar luxation in the left stifle of 24 dogs. SF and blood samples were collected at 1.5- and 3-month intervals, respectively. Every 3 months, one dog was euthanatized to collect tissue samples from both stifles. TRAP levels in SF and serum were measured using a spectrophotometer, and TRAP-positive cells in joint tissues were identified by enzyme histochemistry. MMP-2 and TIMP-2 in SF and serum were detected by Western blotting and ELISA, respectively. TRAP in SF from the stifles and serum was significantly increased (p < 0.05) after 3 months. TIMP-2 in SF and serum was significantly decreased (p < 0.05), whereas MMP-2 in SF was significantly increased (p < 0.05) during the progression of OA. Histochemistry revealed an increased number of TRAP-positive cells in tissues from OA-affected joints. Assays measuring TRAP, MMP-2, and TIMP-2 in SF and serum, and methods that detect increased numbers of TRAP-positive cells in the joint tissues can play an important role in identifying the early phases of degenerative changes in canine joint components.

Status of lipid peroxidation, glutathione, ascorbic acid, vitamin E and antioxidant enzymes in patients with osteoarthritis.

BACKGROUND: The exact pro-oxidant and antioxidant status in osteoarthritis patients is still not clear. To add a new insight to the question, changes in the erythrocyte lipid peroxidation products (MDA), levels of glutathione (GSH), ascorbic acid and plasma vitamin E (nonenzymatic antioxidant parameters); and activities of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase in erythrocytes and plasma glutathione - S - transferase (GST) were measured in patients with osteoarthritis. AIM: This work was undertaken to assess oxidative stress and antioxidant status in patients with osteoarthritis. SETTINGS AND DESIGN: The study was conducted in 20 patients and compared to controls. Levels of erythrocyte MDA, GSH, ascorbic acid, plasma vitamin E; and activities of antioxidant enzymes were measured in patients with osteoarthritis. MATERIALS AND METHODS: Erythrocyte GSH was measured by the method of Beutler et al. Ascorbic acid levels were measured by the method of Tietz. Plasma vitamin E levels were measured by the method of Baker et al. MDA was determined as the measure of thio barbituric acid reactive substances (TBARS). SOD activity in the hemolysate was measured by the method of Misra and Fridovich. Activity of catalase was measured by the method of Beers and Sizer. GPX activity was measured as described by Paglia and Valentine in erythrocytes and Plasma GST activity was measured as described by Warholm et al. These parameters were measured in 20 patients and compared to controls. STATISTICAL ANALYSIS: Statistical analysis between group 1 (controls) and group 2 (patients) was performed by the student's t - test using the stat -view package. RESULTS: It was observed that there was a significant increase in erythrocyte MDA levels; SOD, GPX and plasma GST activities; and a significant decrease in erythrocyte GSH, ascorbic acid, plasma vitamin E levels and catalase activity in patients with osteoarthritis when compared to controls. CONCLUSIONS: The results of our study suggest higher oxygen-free radical production, evidenced by increased MDA and decreased GSH, ascorbic acid, vitamin E and catalase activity, support to the oxidative stress in osteoarthritis. The increased activities of antioxidant enzymes may be a compensatory regulation in response to increased oxidative stress.

Efectos de Diclofenac, Celecoxib y sulfato de glucosamina sobre marcadores inflamatorios en cultivo de condrocitos de pacientes con osteoartritis / Articular cartilage in osteoarthritic patients: effects of diclofenac, celecoxib and glucosamine sulfate on inflammatory markers

La osteoartritis (OA) es una enfermedad articular crónica, progresiva que se instala como consecuencia de un proceso complejo que involcra alteraciones mecánicas y biológicas del sistema músculo-esquelético, siendo resultante de múltiples interacciones entre factores genéticos e injurias extrínsecas. La patogenia de esta enfermedad se ralaciona con alta y desviada producción de citokinas flogógenas y de enzimas proteolíticas, que degradan y destruyen la matriz extracelular en tejidos articulares y peri-articulares. Se estudiaron 20 casos con OA, de los cuales se obtuvo cartílago durante intervenciones quirúrgicas programadas. El cartílago se cultivó en medio Dulbecco-Eagle, con o sin agregado de AINEs o condromodulares. En los sobrenadantes se determinaron óxido nítrico por reacción de Giess y la medición espectrofotométrica; y colagenasa por ELISA doble sándwich en presencia de anticuerpos monoclonales. En ausencia de AINEs, los cultivos de condrocitos produjeron 1950 ± 665ng/ml de MMP-1, La adición de Diclofenac redujo esa cifra a 1140 ± 155 ng/ml, aunque esta diferencia no fue estadisticamente significativa, (p<0.60). Por el contrario, Celecoxib redujo el nivel de la enzima a 760 ± 75ng/ml (p<0,01) y la Glucosamina también provocó un descenso (950 ± 89 ng/ml) significativo (p<0.05). Los niveles de ON en ausencia de AINEs llegaron a 47,3 ± 4,9 µM. Su producción no varió significativamente con la adición de Diclofenac, Ceecoxib o Glucosamina (p=ns). Los resultados indicarían la incapacidad de Diclofenac para modificar la generación de enzimas proteolíticas, mientras que Celecoxib y Glucosamina disminuyen su producción significativamente. Ninguno de los fármacos utilizados en nuestro trabajo ha logrado alterar la concentración de ON. Muchos integrantes quedan aún sin resolver y todavía se carece de fármacos de eficacia comprobada para alterar el curso natural de la enfermedad.

Osteoarthritis is a chronic and progressive joint disease. It is established by a complex process involving mechanical and biological alterations of the musculoskeletal system, which are generated by a great variety of interactions between genetic factors and extrinsic injuries. The pathogenesis of this disease is related to an increased and divergent production of inflammatory markers and proteolytic enzymes that promote the degradation and destruction of the extracellular matrix of articular and periarticular tissues. Cartilage samples were taken from 20 osteoarthritic patients during programmed surgical interventions. The cartilage samples were cultured in Dulbecco-Eagle medium, with or without the addition of NSAIDs or modulators of chondrocyte metabolism. The content of nitric oxide in the supernatant was quantified using the Griess reaction; the concentration of MMP-1 was quantified via double-sandwich ELISA. Untreated chondrocyte cultures produced 1950 +/- 665 ng/ml MMP-1. With the addition of Diclofenac this value decreased to 1140 +/- 155 ng/ml, although this difference was not statistically significant (p < 0.06). However, in the presence of Celecoxib the level significantly dropped to 760 +/- 75 ng/ml (p < 0.01). Although the addition ofglucosamine did not produce such a noticeable reduction in the level of MMP-1 (950 +/- 89 ng/ml), it was statistically significant (p < 0.05). On the contrary, none of the drugs (Diclofenac, Celecoxib, Glucosamine) modified the level of nitric oxide which had a mean value of 47.3 +/- 4.9 microM in the control samples. This investigation evidenced the inability of Diclofenac to significantly modify the production of proteolytic enzymes in osteoarthritic chondrocyte cultures. However, both Celecoxib and Glucosamine significantly reduced the production of MMP-1. On the contrary, none of the drugs used in this study managed to modify the concentration of nitric oxide. To the present day, no drugs have been found to be...

Structure and secretory activity of cultured chondrocytes from patients with osteoarthritis

Cartilage samples were taken from OA patients in order to describe and quantify pro-inflammatory mediators. Samples were cultured under aseptic conditions in Dulbecco's modified Eagle medium at 37°C for 10 days. Control samples, taken from non-inflammatory cartilage, were cultured under the same conditions. The levels of NO-2 and NO-3 were measured in the supernatant using a spectrophotometric assay. The activity of MMP-1 was quantified by ELISA.The concentration of NO-x was 47.3 ± 4.1 µM in the OA cartilague and 10.7 ± 1.8 µM in the controls. The average MMP-1 activity was 3,650 ± 387 ng/ml in the OA cartilage and 2,150 ± 190 ng/ml in the control samples. These increased values of MMP-1 and NO- x observed in the OA cartilage suggest a higher catabolic activity. A morphological analysis of OA chondral tissue using light microscopy shows that the surface of the tissue is characterized by the presence of aggregated chondrocytes or "clones" but in the deeper areas isolated cells are found. These results could be a significant contribution towards the identification of biological markers indicating the presence of OA activity

Expression of cyclooxygenase-1 and -2 in rheumatoid arthritis synovium

The aim of this study was to investigate the expression and localization of cyclooxygenase-1 and -2 (COX-1 and COX-2) in synovial tissues from patients with rheumatoid arthritis (RA). Synovial tissues from 9 patients with RA and 5 patients with osteoarthritis (OA) were examined for COX-1 and COX-2 expressions by immunohistochemical staining using 2 polydonal COX-1 and COX-2 antibodies. In RA synovia, synovial lining cells showed intense immunostaining for COX-1, whereas slight to moderate staining was observed in inflammatory cells, stromal fibroblast-like cells and vascular endothelial cells. There was no significant difference in COX-1 expression between RA and OA synovia. The localization of COX-2 expression dearly differed from that of COX-1 expression, being most intense in inflammatory cells. However, there was no difference in COX-1 and COX-2 expressions between RA and OA synovial tissues. Our observations support that inflammatory mechanisms modulated by COX-1 and COX-2 in chronic RA synovium might be similar to those in chronic OA synovium.

Incremento en la produccion de colagenasa en incubado de sinoviocitos de pacientes com artritis reumatoidea y osteoartrosis / Collagenase production increases in rheumatoid arthritis and ostheoarthritis synoviocytes incubated

El cartílago articular es un tejido paucicelular, con colágeno y proteoglicanos en la matriz extracelular. Su degradación es función de los sinoviocitos, que segregan metaloproteasas que catabolizan a los proteoglicanos. Se distinguen los sinoviocitos A o macrofágicos y los sinoviocitos B o fibroblásticos. La destrucción de proteoglicanos puede ser LT- dependiente o independiente. Nuestro objetivo fue estudiar ex vívo el rol de los sinoviocitos, sin la influencia del sistema inmune. Líquido sinovial de pacientes de ambos sexos, 70ñ2años, con OA(6) y AR(6), vírgenes de tratamiento, se centrifugó 30 minutos a 1500 g, para aislar sinoviocitos. El sedimento se incubó 6 hs en medio Dulbecco-Eagles, con 26 mM de HEPES Gibco, NaHCO3 ( 0.5g/l), glutamina (2 mM), estreptomicina (100mg/l), penicilina (1 U/ml) y anfotericina B (2.5mg/l). Identidad y viabilidad celulares se determinaron con técnicas citopatológicas. Las muestras control provinieron de artritis traumática o patología osteoarticular no-inflamatoria. Con anticuerpos monoclonales anti-MMPs(10mg/ml), previo bloqueo de producción de proteínas inespecíficas con albúmina sérica bovina, se midió actividad colagenasa (MMP-1) antes y después de incubar con ELISA-doble-sandwich. Con streptavidin-peroxidasa se desarrolló color y por absorbancia a 410 nm, se leyó la complejación de los anticuerpos marcados. La secreción de MMP-1 por sinovio-citos AR fue 1373ñ115 ng/ml. Con 6 hs de incubado aumentó hasta 2143ñ132ng/l (-56 por ciento)(p<0.0001), probablemente por la hipercelularidad. Los sinoviocitos OA secretaron 276 ñ 23 ng/ml , y 542 ñ 47 ng/ml tras la incubación (96 por ciente)(p<0.001). Hay paralelismo entre la producción de MMP-1 y la observación microscópica. Sinoviocitos con abundante citoplasma corresponden a altos niveles de enzima. La baja secreción de MMPs responde a escasa población celular y núcleos picnóticos. Aunque en AR la producción de MMPs fue 4.6 veces mayor que en OA, en cambio el incremento porcentual tras la incubación fue casi el doble en OA que en AR. Esos resultados confirman que la producción enzimática varía con la inflamación, que es mayor en los procesos agudos, y que la incubación de sinoviocitos permite detectar cambios patológicos locales

Synovial fluid collagenase and acid prosphatase in rheumatoid arthritis and osteoarthritis

Svnovial fluid from the knee joints of 3l rheumatoid arthritis [RA] patients [17 active and 14 inactive] and 27 patients with osteoarthritis [OA] were studied to detect the enzymatic activity of collagenase and acid phosphatase. The activity of both enzymes showed a significant increase in patients with active RA than those with inactive disease synovial fluid collagenase and acid phosphatase in RA patients Showed a significant correlation with ESR, morning stiffness, Pain Score, articular index and grip strength while an insignificant correlation with age and disease duration was recorded. There was a significant increase in the activity of both enzymes in RA patients when compared with OA patients