Synovial Fluid Cytokine Levels Research Articles

Low-Protein Diet Inhibits the Synovial Tissue Macrophage Pro-Inflammatory Polarization Via NRF2/SIRT3/SOD2/ROS Pathway in K/BxN Rheumatoid Arthritis Mice.

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by pain, swelling, stiffness, and impaired function. Attenuating inflammation is a crucial objective in RA management. Diet and nutrition are believed to influence RA symptomatology, with a low-protein diet being one potential nutritional strategy, although its underlying mechanisms remain to be fully elucidated. In this research, serum derived from arthritic transgenic K/BxN mice was administered to naive mice to establish a K/BxN rheumatoid arthritis model. Physiological assessments and histological staining were performed to evaluate joint pathology. (Enzyme-linked immunosorbent assay) ELISA was used to measure inflammatory cytokines. Flow cytometry and immunofluorescence were applied to characterize macrophage phenotypes. Transcriptomic analysis elucidated molecular pathways under the effect of a low-protein diet and verified by immunoblotting. Mitochondrial reactive oxygen species (ROS) was detected by Mito-SOX. Protein expression was silenced through the application of siRNA transfection. Our results indicate that a low-protein diet significantly alleviates disease symptoms and decreases pro-inflammatory cytokine levels in synovial fluid. Furthermore, this dietary intervention inhibits M1 macrophage polarization while promoting a shift towards the M2 phenotype. Transcriptomic analysis revealed that the beneficial effects of the low-protein diet in alleviating rheumatoid arthritis are closely linked to the NRF2 pathway. In vitro, low protein treatment can promote the activity of NRF2 via inhibiting the ubiquitin mediated proteolysis and activate the NRF2/SIRT3/SOD2 pathway to inhibit the production of ROS, which will further inhibit the M1 macrophage polarization. NRF2 knockdown can abolish the effects of low-protein treatment, indicating that the inhibition of M1 polarization and the anti-inflammatory response induced by low-protein treatment are dependent on NRF2. In summary, our findings propose that low-protein diet can inhibit synovial macrophage M1 polarization via activating NRF2/SIRT3/SOD2 pathway to reduce mitochondrial ROS production. This mechanism effectively decreases synovial inflammation and alleviates RA symptoms.

The Relationship Between Intra-articular Fracture Energy and a Patient's Inflammatory Response.

Prior studies have demonstrated elevated inflammatory cytokine concentrations in the synovial fluid of articular fracture patients postinjury. Similarly, CT-based fracture energy measurements have been correlated with posttraumatic osteoarthritis risk after pilon fracture. The purpose of this study was to determine the associations between synovial fluid cytokine levels, fracture energy, and overall trauma to the body in articular fracture patients. Acute tibial plateau, tibial plafond, and rotational ankle fracture patients were prospectively enrolled from December 2011 through January 1, 2019. Synovial fluid concentrations of interleukin-1 beta, interleukin-1 receptor antagonist, IL-6, IL-8, IL-10, matrix metallopeptidase-1, MMP-3, and MMP-13 were quantified. Patient CT scans were used to calculate fracture energy. The Injury Severity Score (ISS) was used to relate cytokine levels to whole-body injury severity. Spearman rho correlation coefficients were calculated to assess the relationship between injury severity metrics and synovial fluid cytokine, chemokine, and matrix metallopeptidase concentrations. Eighty-seven patients were enrolled with 42 had a tibial plateau fractures (OTA/AO 41B1-2, 41B2-14, 41B3-3, 41C1-3, 41C2-4, 41C3-16), 24 patients had a tibial plafond fracture (OTA/AO 43B1-2, 43B2-4, 43B3-5, 43C1-2, 43C2-3, 43C3-8), and 21 had a rotational ankle fracture (OTA/AO 44B1-3, 44B2-3, 44B3-6, 44C1-4, 44C2-5). Fracture energy significantly differed between fracture patterns, with ankle fractures involving substantially less fracture energy (median = 2.92 J) than plafond (10.85 J, P < 0.001) and plateau fractures (13.05 J, P < 0.001). After adjustment for multiple comparisons, MMP-3 was significantly correlated with transformed fracture energy (r = 0.41, 95% confidence interval [CI], 0.22-0.58, P < 0.001), while IL-1β was significantly correlated with the Injury Severity Score (Spearman ρ = 0.31, 95% CI, 0.08-0.49, P = 0.004). Synovial fluid MMP-3 concentration was significantly correlated with CT-quantified fracture energy in intra-articular fracture patients. Given that in clinical practice fracture energy tends to correlate with posttraumatic osteoarthritis risk, MMP-3 may warrant further investigation for its role in posttraumatic osteoarthritis development after articular fracture. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Analysis of synovial biomarkers with a multiplex protein microarray in patients with PJI undergoing revision arthroplasty of the hip or knee joint.

Diagnosing a (low-grade) periprosthetic joint infection (PJI) after hip or knee arthroplasty remains a diagnostic challenge. The aim of this study was to evaluate the utility of using a novel multiplex protein microarray system for synovial biomarkers in determining PJI in patients undergoing revision knee or hip arthroplasty. The individual synovial fluid levels of 12 cytokines (IL-1b, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, IL-17, GM-CSF, TNF-α, and INF-γ) were analysed with a novel multiplex protein microarray system in 32 patients undergoing revision hip (n = 22) or knee (n = 10) arthroplasty. Cases were classified into septic and aseptic groups on basis of pre- and interoperative findings: [PJI (n = 14) vs. non-PJI (n = 18)]. Receiver operator characteristic (ROC) curves were calculated to assess the discriminatory strength of the individual parameters. A multiple regression model was used to determine the utility of using a combination of the tested cytokines to determine the infection status. The levels of all of the evaluated cytokines were significantly elevated in the PJI-group. Best sensitivity and specificity were found for IL-6, followed by IL-1b, IL-10, and IL-17. The multiple regression models revealed a combination of IL-2, IL-4, IL-5, IL6, lL-12, and GM-CSF to be associated with the best sensitivity (100%) and specificity (88.9%) for a cut-off value of 0.41, with a likelihood ratio of 9.0. Analysis of individual synovial fluid cytokine levels showed both high sensitivity and high specificity in diagnosing PJI. A combined model using several cytokines showed even higher sensitivity and specificity in diagnosing PJI and could thus be a useful predictive tool to determine the probability of PJI in patients with a painful prosthesis. Diagnostic IV.

Postoperative Serum Cytokine Levels Are Associated With Early Stiffness After Total Knee Arthroplasty: A Prospective Cohort Study

BackgroundInflammatory cytokines have been implicated in organ fibrosis; however, their role in the development of arthrofibrosis after total knee arthroplasty (TKA) has not been well explored. The purpose of this study is to assess whether perioperative synovial fluid or blood plasma cytokine levels are associated with reduced early post-TKA range of motion. MethodsA total of 179 patients with end-stage idiopathic osteoarthritis undergoing TKA were enrolled in this prospective cohort study. Synovial fluid and blood plasma were collected prearthrotomy and plasma was collected longitudinally in the postacute care unit and on postoperative days (PODs) 1 and 2. Stiffness was defined as ≤95° range of motion measured with a goniometer at 6 weeks (±2 weeks). ResultsThirty-two of 162 (19.8%) patients analyzed were stiff at 6 weeks postoperatively. Postoperative plasma levels of 9 cytokines (Eotaxin3, IL-5, IL12_23p40, IP10, VEGF, IL-7, IL-12p70, IL-16, IL-17a) were significantly different between stiff and nonstiff patients on POD1 and/or POD2. An association between preoperative plasma and synovial fluid cytokine levels and the development of postoperative stiffness was not detected. ConclusionThe results of this study suggest that there is a distinct acute postoperative cytokine response profile in patients who develop stiffness 6 weeks after TKA. This profile was characterized by significant differences in levels of 9 cytokines over the first 2 postoperative days. These results identify cytokines that are potential biomarkers for risk of early stiffness after TKA and may play a role in the pathophysiology of this outcome.

Effect of Sodium Hyaluronate on Inflammatory Cytokine Levels in Synovial Fluid of Patients with Knee Osteoarthritis

This study evaluated the efficacy of intraarticular injection of sodium hyaluronate in the treatment of knee osteoarthritis and its influence on the levels of stromal cell-derived factor-1 and matrix metalloproteinases 3, 9 and 13 in the synovial fluid of patients with knee osteoarthritis. A total of 180 patients with knee osteoarthritis treated in the orthopaedic outpatient department of the Hubei Provincial Hospital from April 2015 to April 2017 were selected as the research objects and all of them were given intraarticular injection of sodium hyaluronate with synovial fluid extracted before the injection, 1 and 3 mo after the injection, and the level of stromal cell-derived factor-1 and matrix metalloproteinases 3, 9, 13 were determined using a sandwich enzyme-linked immunosorbent assay method. After 3 mo of treatment, the effect on the efficacy of patient’s gender, age, body mass index, swollen joint degree, involved joint space, Kellgren and Lawrence grading as well as tibiofemoral angle were observed and studied. Among the 180 cases there were 132 cases with 73.3% effective rate and 48 cases of with ineffective rate of 26.7%. Significant differences were found in the levels of stromal cell-derived factor-1, matrix metalloproteinases 3, 9 and 13 in the synovial fluid before the treatment, 1 and 3 mo after the treatment (p 1.7 in joint effusion and osteoarthritis involving tibiofemoral joint gap. In the treatment of knee osteoarthritis, the intraarticular injection of sodium hyaluronate could effectively reduce the levels of stromal cell-derived factor-1, matrix metalloproteinases 3, 9 and 13 in synovial fluid and decrease inflammatory reaction. But it should be used with great caution for treating patients with moderate and severe knee osteoarthritis involving tibial and femoral joints with the joint effusion graded above II or bone contusion.

Inflammatory cytokines and matrix metalloproteinases in the synovial fluid after intra-articular elbow fracture

Post-traumatic elbow contracture remains a common and challenging complication with often unsatisfactory outcomes. Although the etiology is unknown, elevated or abnormal post-fracture synovial fluid cytokine levels may result in the migration of fibroblasts to the capsule and contribute to capsular pathology. Thus, the purpose of this study was to characterize the cytokine composition in the synovial fluid fracture hematoma of patients with intra-articular elbow fractures. The elbow synovial fluid fracture hematoma of 11 patients with intra-articular elbow fractures was analyzed for CTXII (C-terminal telopeptides of type II collagen [a cartilage breakdown product]) as well as 15 cytokines and matrix metalloproteinases (MMPs) including interferon γ, interleukin (IL) 1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor α, MMP-1, MMP-2, MMP-3, MMP-9, and MMP-10. The uninjured, contralateral elbow served as a matched control. Mean concentrations of each factor were compared between the fluid from fractured elbows and the fluid from control elbows. The levels of 14 of 15 measured cytokines and MMPs-interferon γ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor α, MMP-1, MMP-3, MMP-9, and MMP-10-were significantly higher in the fractured elbows. In addition, post hoc power analysis revealed that 10 of 14 significant differences were detected with greater than 90% power. The mean concentration of CTXII was not significantly different between groups. These results demonstrate a proinflammatory environment after fracture that may be the catalyst to the development of post-traumatic elbow joint contracture. The cytokines with elevated levels were similar, although not identical, to the cytokines with elevated levels in studies of other weight-bearing joints, indicating the elbow responds uniquely to trauma.

Curcumin reduces inflammation in knee osteoarthritis rats through blocking TLR4 /MyD88/NF-κB signal pathway.

Preclinical Research & Development Curcumin has been shown to possess a series of beneficial effects, such as antiinflammatory, antioxidant, analgesic, and promoting healing. However, the effect and relative mechanism of curcumin on knee osteoarthritis (OA) have not been elucidated. The aim of this study is to explore the protective effect of curcumin on monosodium iodoacetate (MIA)-induced OA. Forty-eight rats were randomized into four experimental groups: control group, OA group, OA + PBS group, and OA + curcumin group, respectively. A single intraarticular injection of MIA was applied to establish the rat model of knee OA. Hematoxylin-eosin staining was used to evaluate histological changes of knee joint. The paw withdrawal threshold was collected and the expression of synovial fluid cytokine levels was measured by ELISA. The protein expression of TRL-4, MyD88, p-IκBα, NF-κB, TNF-α, IL-1β, and IL6 was measured by western blot. Treating with curcumin can significantly reduce joint diameter and Mankin's score, and increase the paw withdrawal threshold. The expression of synovial fluid inflammatory biomarkers, IL-6, IL-1β, and TNF-α in the OA + curcumin group were lower than that in OA and OA + PBS group. The protein expression of the TLR4 receptor was increased in the OA, OA + PBS, and OA + curcumin group compared to the control group. However, curcumin treatment can significantly decrease the expression of MyD88, p-IκBα, NF-κB, TNF-α, IL-1β, and IL6 in OA + curcumin group. These findings may indicate that curcumin could block TLR4/NF-κB signal pathway, and reduce inflammation level to prevent knee wound in OA rats. Curcumin may be a feasible kind of medicament in the treatment of knee OA.

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The objective of the study was to evaluate cytokine concentration and profile of lipid peroxidation in synovial fluid of patients with osteoarthritis and concomitant defects of articular surfaces. Material and methods Synovial fluid samples were taken from 102 patients with osteoarthritis of the knee joint. Patients with rheumatoid arthritis, osteoarthritis of a post-traumatic etiology, and somatic diseases that could affect results of the study were excluded from the study. Thirty control samples originated from deceased donors of both genders. Synovial fluid was extracted in compliance with Ministry of Health Order No. 694 dtd July 21, 1978, p. 2.24 Guidelines of forensic medical examination in the USSR. Results Findings of laboratory studies showed statistically significant differences in synovial fluid cytokine levels depending on absence or presence of defects on the tibial condyles. Biochemical tests revealed greater changes in lipid peroxidation in patients with articular defects. Total level of lipid peroxidation products resulting in the formation of conjugated dienes (CD), malondialdehyde (MDA) was shown to increase in both groups of patients being significantly higher in patients with defects on articular surfaces. Primary (conjugated dienes) and secondary (malondialdehyde) lipid peroxidation products accumulated in the synovial fluid of the patients with the levels being significantly increased in both groups with no changes in the CD/MDA ratio. Patients with defects on articular surfaces demonstrated increased formation of primary products, and non-defect group showed greater formation of secondary products. Antioxidant enzyme, catalase, appeared to me more active in patients of Group I. Conclusion The findings can be used to evaluate defects on articular surface and identify strategies of medication therapy.

Synovial fluid cytokine levels in diagnosis of indolent prosthetic shoulder joint infection

Periprosthetic joint infection is one of the most serious complications associated with arthroplasty surgery and poses great diagnostic difficulty. Traditional diagnostic methods used to diagnose infection in the lower extremity are less accurate for shoulder prosthetic joint infection due to the indolent nature of the most common pathogen, Propionibacterium acnes. In addition to preoperative lab work and intraoperative tissue cultures, a more recent tool for the evaluation of periprosthetic infection has been analysis of synovial fluid for antimicrobial peptides and cytokines. Investigation of synovial biomarkers such as α-defensin and interleukins offers improved ability to more accurately diagnose prosthetic shoulder joint infection.

Inflammatory cytokine levels in synovial fluid 3, 4days postoperatively and its correlation with early-phase functional recovery after anterior cruciate ligament reconstruction: a cohort study.

BackgroundSynovial fluid was collected prior to and at 3 to 4 days after ACL reconstruction to investigate the correlation between inflammatory cytokine levels in the acute phase after surgery and physical functional recovery at 3 months postoperatively.Methods For this purpose, 79 patients with ACL reconstruction using semitendinosus tendons were included in the study. Median days from injury to surgery were 80 days (13–291 days). Synovial fluid was obtained just before surgery and at 3 to 4 days after surgery. Physical activity of each patient was evaluated at 3 months postoperatively, and scored from 0 (hard to walk) to 5 (run). Patients able to jog (score 4) or run (score 5) were considered as the “quick recovery” group and others (scores 1–3) as the “delayed recovery” group.ResultsPhysical activity recovery scores in the early surgery group (preoperative period less than 60 days; Group I) were significantly better than those in the delayed surgery group (Group II). Among the cytokines tested, TNF-alpha and IL10 levels in synovial fluid were significantly higher in Group II at 3 to 4 days postoperatively, while levels of these cytokines were quite comparable preoperatively between the groups. Increased IL1-beta expression was noted in the delayed recovery group at 3 to 4 days postoperatively. In addition, levels of IL6, IL10 and IFN-gamma also tended to increase in patients with delayed recovery.ConclusionDelayed ACL reconstruction increases levels of inflammatory cytokines in synovial fluid after surgery and correlates with a prolonged recovery of short-period physical activity of the patients.

Effects of ACL Reconstructive Surgery on Temporal Variations of Cytokine Levels in Synovial Fluid.

Anterior cruciate ligament (ACL) reconstruction restores knee stability but does not reduce the incidence of posttraumatic osteoarthritis induced by inflammatory cytokines. The aim of this research was to longitudinally measure IL-1β, IL-6, IL-8, IL-10, and TNF-α levels in patients subjected to ACL reconstruction using bone-patellar tendon-bone graft. Synovial fluid was collected within 24–72 hours of ACL rupture (acute), 1 month after injury immediately prior to surgery (presurgery), and 1 month thereafter (postsurgery). For comparison, a “control” group consisted of individuals presenting chronic ACL tears. Our results indicate that levels of IL-6, IL-8, and IL-10 vary significantly over time in reconstruction patients. In the acute phase, the levels of these cytokines in reconstruction patients were significantly greater than those in controls. In the presurgery phase, cytokine levels in reconstruction patients were reduced and comparable with those in controls. Finally, cytokine levels increased again with respect to control group in the postsurgery phase. The levels of IL-1β and TNF-α showed no temporal variation. Our data show that the history of an ACL injury, including trauma and reconstruction, has a significant impact on levels of IL-6, IL-8, and IL-10 in synovial fluid but does not affect levels of TNF-α and IL-1β.

The effects of nonsteroidal anti-inflammatory drugs on clinical outcomes, synovial fluid cytokine concentration and signal transduction pathways in knee osteoarthritis. A randomized open label trial

We investigated the effects of celecoxib, diclofenac, and ibuprofen on the disease-specific quality of life, synovial fluid cytokines and signal transduction pathways in symptomatic knee osteoarthritis (OA). Ninety patients scheduled for a total knee arthroplasty (TKA) were randomized to six groups that were treated with low and high dosages of celecoxib, diclofenac or ibuprofen. At the time of the first admission (T0) and at surgery (T1=14 days after beginning of the nonsteroidal anti-inflammatory drugs (NSAIDs)), samples of knee synovial fluid were obtained from each patient for analysis. During the surgery the synovial tissue was harvested from the knee of patients. The Western Ontario and McMaster universities (WOMAC) score was used to evaluate the patient disease-specific quality of life at T0 and T1. Microarray tests performed at T0 and T1 were used to evaluate the effects of NSAIDs on Tumor necrosis factor (TNF)-alpha, Interleukin-6 (IL-6), IL8 and Vascular endothelial growth factor (VEGF) concentration in the synovial fluid. Western blot assays evaluated the effects of NSAIDs on MAP kinase (MAPK) signal transduction pathway in the synovial membrane. NSAID treatment induced a statistically significant improvement in the WOMAC score and a statistically significant decrease in the IL-6, VEGF and TNF-alpha concentration in the synovial fluid. Higher dosages of NSAIDs provided a greater improvement in the disease-specific quality of life of patients and lower concentrations of pro-inflammatory cytokines in the synovial fluid. Inhibition of MAPKs was noted after NSAID treatment. Short-term NSAID treatment improves the patient disease-specific quality of life with a parallel decrease in pro-inflammatory synovial fluid cytokine levels in knee OA. Signal transduction pathways may be involved in regulating the anti-inflammatory effects of NSAIDs. ClinicalTrial.gov: NCT01860833.

Abstract 3: Apolipoprotein A-I Inhibits Streptococcal Cell Wall-Induced Arthritis in the Rat in an ABCA1-dependent Manner

Introduction. Arthritis is a chronic inflammatory disease characterized by joint inflammation and destruction, reduced high-density lipoprotein (HDL) levels, and increased cardiovascular risk. Objective To determine if apolipoprotein (apo) A-I, the main HDL apolipoprotein, prevents joint inflammation in arthritis. Methods and Results In vivo: Arthritis was induced in female Lewis rats with a single 15 mg/kg intraperitoneal streptococcal cell wall peptidoglycan-polysaccharide (PG-PS) injection and quantified as a combined forepaw and hindpaw inflammation score. Arthritis progressed from an initial, acute phase of joint inflammation during the first 4 days post-PG-PS administration to remission by day 8, followed by chronic joint inflammation up to sacrifice at day 21. Two intravenous infusions of lipid-free apoA-I (8 mg/kg) 24 h pre- and 24 h post-PG-PS injection reduced the acute and chronic joint inflammation by 63±9% at day 3 and by 61±8% at day 21. Infusion of apoA-I at days 7, 9 and 11 post-PG-PS injection reduced the chronic response by 43±11% at day 21. ApoA-I infusions at 24 h prior to and at days 1, 7, 9, 11 post-PG-PS injection reduced joint inflammation by 61±5% at day 3 and by 90±5% at day 21 (p&lt;0.05 for all vs saline infusion). These beneficial effects of apoA-I were accompanied by a reduced inflammatory white blood cell count, reduced pro-inflammatory cytokine levels in synovial fluid, and reduced macrophage accumulation, toll-like receptor 2 (TLR2) and inflammatory cytokine expression in synovial tissue. In vitro: Human monocyte-derived macrophages (HMDMs) were pre-incubated with lipid-free apoA-I, then stimulated with PG-PS (20 μg/mL). Pre-incubation with apoA-I inhibited PG-PS-induced TLR2 and MyD88, a TLR2 adapter protein, expression. Nuclear factor-κB activation and pro-inflammatory cytokine production were also attenuated. These anti-inflammatory effects of apoA-I were abolished in HMDMs transfected with ATP-binding cassette transporter 1 (ABCA1) siRNA. Conclusions These findings establish that apoA-I attenuates PG-PS induced arthritis in the rat. These effects may involve ABCA-1 and inhibition of TLR2 expression and activation.

Dynamic analysis of cytokine expression in synovial fluid after anterior cruciate ligament reconstruction surgery

Purpose: Synovial fluid is an interstitial fluid secreted by fibroblast-like cells in the synovial membrane. It is a highly viscous liquid containing hyaluronic acid and various cytokines. The physiological functions of synovial fluid include reduction of friction, shock absorption, nutrient, and waste transportation in the joint. In addition, previous reports showed that mesenchymal stem cell-like cells, those are considered to contribute the tissue regeneration, reside in synovial fluid and the number of these cells increased after joint injury. These data strongly suggest that condition of synovial fluid may greatly influence joint homeostasis. This study aims the dynamic analysis of cytokine levels in synovial fluid after anterior cruciate ligament reconstruction surgery (ACL-R). Since ACL-R patients are regarded as a high-risk osteoarthritis (OA) group as it was reported that more than 30% of ACL-R patients develop radiographic OA on an average of 7.8 years after surgery, with most patients having no evidence of OA at the time of ACL-R, we expect that this study will give us critical information to identify prognostic factors for joint degeneration after injury. Methods: This study was approved by the Ethics Committee of this institute. All patients included in this study gave their full, written, informed consent for participation prior to the operative procedure. Synovial fluid was obtained from the patients who underwent ACL-R from January till August 2012 in our university hospital (Just before surgery, at day 3, at 3 weeks, and at 5 weeks post surgery: 26 samples, female: 13 male: 13, 14-62 year-old, average 30 year-old). Cytokine levels in synovial fluid were measured by ELISA (R and D systems, MN). In this report, we examined TNF-alpha and IL1-beta as pro-inflammatory cytokines and BMP7 as an anti-inflammatory and anti-catabolic factor for articular cartilage. Pearson's correlation coefficient test, Wilcoxon single-rank test, or Mann-Whitney's U-test were employed for the statistical analysis and values of p < 0.05 were considered significant. Results: Before ACL-R, average volume of synovial fluid was 7.6+/-7.2ml although it varied from individual patient (Max 15.5ml, Min 0.5ml). In all patients, synovial fluid volume surged around 3-fold at day 3 post surgery (average 21.6+/-8.0ml, Max 25ml, Min 7.8ml). In most patients, synovial fluid volume returned to the basal level within 3 weeks post surgery. Concentrations of TNF-alpha and IL1-beta were significantly increased at day 3 post surgery if compared to those at pre-operation (p<0.05). In addition, the concentration of TNF-alpha was positively correlated with the volume of synovial fluid at pre-operation (r=0.995, p<0.01) and day3 post-operation (r=0.535, p<0.05) while IL1-beta levels were not at any time point. Throughout the time point, BMP7 levels were very low and did not change significantly at pre- and post-operation. Surprisingly, BMP7 levels were positively correlated with IL1-beta levels at day 3 post-operation (r=0.59, p<0.01). These suggest that BMP7 may have subtle anti-inflammatory/anti-catabolic effect on cartilage at the acute inflammatory stage after joint injury. Conclusion: This is a longitudinal study of dynamic analysis of cytokine levels in synovial fluid from each patient undergoing ACL-R. In this report, we examined the levels of TNF-alpha, IL1-beta, and BMP7 in synovial fluid and observed that TNF-alpha levels were significantly correlated with the volume of synovial fluid.

Differences in synovial fluid cytokine levels but not in synovial tissue cell infiltrate between anti-citrullinated peptide/protein antibody-positive and –negative rheumatoid arthritis patients

IntroductionComparative data on synovial cell infiltrate and cytokine levels in anti citrullinated peptide/protein antibody (ACPA)-positive and ACPA negative rheumatoid arthritis (RA) patients are scarce. Our aim was to analyze synovial cell infiltrate and synovial fluid (SF) levels of cytokines in patients with RA according to the presence or absence of ACPA in serum.MethodsA cross-sectional study in a single center including consecutive RA patients was performed. Patients were defined as 'ACPA negative' if serum was negative to two different ACPAs [second generation commercial anti-cyclic citrullinated peptide antibodies (CCP2) and chimeric fibrin/filaggrin citrullinated antibodies]. Parallel synovial tissue (ST) biopsies and SF were obtained by knee arthroscopy. Synovial cell infiltrate and endothelial cells were analyzed by immunohistochemistry and SF levels of Th1, Th2, Th17 and pro-inflammatory cytokines by Quantibody(R) Human Array.ResultsA total of 83 patients underwent arthroscopy, with a mean age of 55.9 ± 12 years, and mean disease duration of 45 months (interquartile range, IQR 10.8 to 122). 62% were female and 77% were ACPA positive. No significant differences were found in clinical variables, acute phase reactants, synovial cell infiltrate or lymphoid neogenesis (LN) between ACPA positive and negative patients. However ACPA positive patients had significantly higher levels of IL-1β, IL-10, IL-17 F and CC chemokine ligand 20 (CCL-20) than ACPA negative patients.ConclusionsIn our cohort of patients with RA no significant differences were found in synovial cell infiltrate or synovial LN according to ACPA status. However, ACPA positive patients had higher levels of T-cell derived and pro-inflammatory cytokines than ACPA negative patients. As systemic and local inflammation was similar in the two groups, these findings support a distinct synovial physiopathology.

Effects of exercise therapy on knee joint function and synovial fluid cytokine levels in patients with knee osteoarthritis

The aims of this study were to observe the effect of exercise therapy on the function of the knee joint and the levels of cytokines and cytokine-related genes, specifically tumor necrosis factor-α (TNF-α), high sensitivity C-reactive protein (hs-CRP) and matrix metalloproteinase-3 (MMP-3), in the synovial joints of patients with knee osteoarthritis (KOA) and to explore its mechanism of action. A total of 100 KOA patients were divided into a treatment group (n=50) and a control group (n=50) according to the order of admission. The patients in the treatment group were treated with diclofenac sodium combined with exercise therapy and the patients in the control group were treated with diclofenac sodium only. The function of the knee joint and the therapeutic efficacy was evaluated and the TNF-α, hs-CRP and MMP-3 levels in the synovial fluid were measured following 4weeks of treatment. The results revealed that the knee joint index score and the TNF-α, hs-CRP and MMP-3 levels in the synovial fluid decreased significantly in the KOA patients of the two groups following treatment (P<0.05). Compared with the control group, the knee joint index score and the TNF-α, hs-CRP and MMP-3 levels in the synovial joints were lower and the therapeutic efficacy was increased in the patients of the treatment group (P<0.05). In brief, exercise therapy may decrease cytokine and cytokine-related gene levels in the synovial fluid and inhibit inflammatory factor-mediated cartilage degradation in KOA patients, thus, effectively improving the clinical symptoms of KOA.

Mitochondrial mutagenesis correlates with the local inflammatory environment in arthritis

BackgroundTo examine the association between mitochondrial mutagenesis and the proinflammatory microenvironment in patients with inflammatory arthritis.MethodsFifty patients with inflammatory arthritis underwent arthroscopy and synovial tissue biopsies, synovial fluid and clinical...

Cytokine profile of autologous conditioned serum for treatment of osteoarthritis, in vitroeffects on cartilage metabolism and intra-articular levels after injection

IntroductionIntraarticular administration of autologous conditioned serum (ACS) recently demonstrated some clinical effectiveness in treatment of osteoarthritis (OA). The current study aims to evaluate the in vitro effects of ACS on cartilage proteoglycan (PG) metabolism, its composition and the effects on synovial fluid (SF) cytokine levels following intraarticular ACS administration.MethodsThe effect of conditioned serum on PG metabolism of cultured OA cartilage explants was compared to unconditioned serum. The effect of serum conditioning on levels of interleukin-1beta (IL-1β), IL-4, IL-6, IL-10, IL-13, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), osteoprotegerin (OPG), oncostatin M (OSM), interleukin-1 receptor (IL-1ra) and transforming growth factor beta (TGF-β) were measured by multiplex ELISA. As TNF-α levels were found to be increased in conditioned serum, the effect of TNF-α inhibition by etanercept on PG metabolism was studied in cartilage explants cultured in the presence of conditioned serum. Furthermore, cytokine levels in SF were measured three days after intraarticular ACS injection in OA patients to verify their retention time in the joint space.ResultsPG metabolism was not different in the presence of conditioned serum compared to unconditioned serum. Levels of the anti-inflammatory cytokines IL-1ra, TGF-β, IL-10 as well as of pro-inflammatory cytokines IL-1β, IL-6, TNF-α and OSM were increased. IL-4, IL-13 and IFN-γ levels remained similar, while OPG levels decreased. TNF-α inhibition did not influence PG metabolism in cartilage explant culture in the presence of condtioned serum. Although OPG levels were higher and TGF-β levels were clearly lower in ACS than in SF, intraarticular ACS injection in OA patients did not result in significant changes in these cytokine levels.ConclusionsACS for treatment of osteoarthritis contains increased levels of anti-inflammatory as well as pro-inflammatory cytokines, in particular TNF-α, but conditioned serum does not seem to have a net direct effect on cartilage metabolism, even upon inhibition of TNF-α. The fast intraarticular clearance of cytokines in the injected ACS may explain the limited effects found previously in vivo.

Radiographic severity of knee osteoarthritis is conditional on interleukin 1 receptor antagonist gene variations

BackgroundA lack of biomarkers that identify patients at risk for severe osteoarthritis (OA) complicates development of disease-modifying OA drugs.ObjectiveTo determine whether inflammatory genetic markers could stratify patients with knee OA...

Joint Injury and Osteoarthritis: Soluble Mediators in the Course and Treatment of Cartilage Pathology

Osteoarthritis is a disabling disease of the aging generation, which results in loss of quality of life and increased healthcare costs. Cytokines appear to play an important role in the cartilaginous degeneration characterizing the pathological process. Increasing experience is being gained with cytokine-modulating therapies aimed at interfering with effects of chondrodegradative cytokines in the synovial fluid. Although in vitro and in vivo effectiveness of several of these therapies has been demonstrated, clinical effectiveness remains disputable, which may be related to the low levels of inflammatory cytokines found in osteoarthritic joints. By contrast, directly after joint trauma, which has been shown to predispose to early osteoarthritis, synovial fluid cytokine levels are strongly increased. Cytokine-modulating therapies, however, have hardly been considered for this indication. Increased knowledge of intra-articular soluble mediators correlating with cartilage pathology will lead to further development of cytokine-modulating products and, eventually, to effective inhibition of cartilage degeneration, in both the osteoarthritic as well as injured joints.