Polychromatic Flow Cytometric Analysis of Stromal Vascular Fraction from Lipoaspirate and Microfragmented Counterparts Reveals Sex-Related Immunophenotype Differences

Mesenchymal stem/stromal cells or medicinal signaling cells (MSC)-based therapy holds promise as a beneficial strategy for treating knee OA (osteoarthritis), but there is no standardized protocols nor mechanistic understanding. In order to gain a better insight into the human MSC from adipose tissue applied for autologous OA treatment, we performed extensive comparative immunophenotyping of the stromal vascular fraction from lipoaspirate or microfragmented lipoaspirates by polychromatic flow cytometry and investigated the cellular components considered responsible for cartilage regeneration. We found an enrichment of the regenerative cellular niche of the clinically applied microfragmented stromal vascular fraction. Sex-related differences were observed in the MSC marker expression and the ratio of the progenitor cells from fresh lipoaspirate, which, in female patients, contained a higher expression of CD90 on the three progenitor cell types including pericytes, a higher expression of CD105 and CD146 on CD31^highCD34^high endothelial progenitors as well as of CD73 on supra-adventitialadipose stromal cells. Some of these MSC-expression differences were present after microfragmentation and indicated a differential phenotype pattern of the applied MSC mixture in female and male patients. Our results provide a better insight into the heterogeneity of the adipose MSC subpopulations serving as OA therapeutics, with an emphasis on interesting differences between women and men.

IL-40: A New B Cell-Associated Cytokine Up-Regulated in Rheumatoid Arthritis Decreases Following the Rituximab Therapy and Correlates With Disease Activity, Autoantibodies, and NETosis

Background

Interleukin 40 (IL-40) is a newly identified B cell-associated cytokine implicated in humoral immune responses and B cell homeostasis. As B cells play a pivotal role in autoimmunity, we investigated the function of IL-40 in rheumatoid arthritis (RA).

Methods

IL-40 expression was determined in the synovial tissue from RA and osteoarthritis (OA) patients. IL-40 was analysed in the serum/synovial fluid of patients with RA (n=50), systemic lupus erythematosus (SLE, n=69), OA (n=44), and healthy controls (HC, n=50). We assessed the changes of IL-40 levels in RA patients following the B cell depletion by rituximab (n=29) or after the TNF inhibition by adalimumab (n=25). We examined the relationship between IL-40, disease activity, autoantibodies, cytokines, and NETosis markers. Effect of IL-40 on synovial fibroblasts was determined.

Results

IL-40 was overexpressed in RA synovial tissue, particularly by synovial lining and infiltrating immune cells. The levels of IL-40 were up-regulated in the synovial fluid of RA versus OA patients (p<0.0001). Similarly, IL-40 was increased in the serum of RA patients compared to HC, OA, or SLE (p<0.0001 for all) and decreased after 16 and 24 weeks (p<0.01 and p<0.01) following rituximab treatment. No significant effect of adalimumab on IL-40 was observed. IL-40 levels in RA patients correlated with rheumatoid factor-IgM and anti-cyclic citrullinated peptides (anti-CCP) in the serum (p<0.0001 and p<0.01), as well as in the synovial fluid (p<0.0001 and p<0.001). Synovial fluid IL-40 was also associated with disease activity score DAS28 (p<0.05), synovial fluid leukocyte count (p<0.01), neutrophil attractants IL-8 (p<0.01), MIP-1α (p<0.01), and markers of neutrophil extracellular traps externalization (NETosis) such as proteinase 3 (p<0.0001) and neutrophil elastase (p<0.0001). Synovial fibroblasts exposed to IL-40 increased the secretion of IL-8 (p<0.01), MCP-1 (p<0.05), and MMP-13 (p<0.01) compared to the unstimulated cells.

Conclusions

We show the up-regulation of IL-40 in RA and its decrease following B cell depleting therapy. The association of IL-40 with autoantibodies, chemokines, and markers of NETosis may imply its potential involvement in RA development. Moreover, IL-40 up-regulates the secretion of chemokines and MMP-13 in synovial fibroblasts, indicating its role in the regulation of inflammation and tissue destruction in RA.

A potential diagnostic serum immunological marker panel to differentiate between primary and secondary knee osteoarthritis

Inflammation contributes to knee osteoarthritis (KOA) where many immunological mediators participate in its initiation and progression. Most clinicians manage primary (pKOA) and secondary osteoarthritis (sKOA) alike. Whether immunological profiles of pKOA and sKOA differ remains obscure. Hence, we aimed to differentially identify potential serum immunologic diagnostic markers of pKOA and of sKOA. This case control study used 46 KOA patients (pKOA, n = 30; sKOA, n = 16), and 60 age, gender matched controls (normal healthy, n = 30; systemic lupus erythematosus [SLE] disease controls, n = 30) where serum was assayed for cytokines (TNF-α, IL-1β, IL-6, IL-10) and nitric oxide derivatives (NOx). Sandwich ELISA assessed cytokine levels, while the ‘Griess assay’ quantified NOx levels. The diagnostic accuracy of optimal marker combinations was evaluated by the CombiROC web tool. Compared with pKOA, sKOA serum displayed significantly elevated levels of pro inflammatory cytokines (TNF-α, IL-1β, IL-6) with a concurrent decrease in the anti-inflammatory cytokine, IL-10 (P<0.05). This was reiterated by significantly higher Th1:Th2 (TNF-α: IL-10) serum cytokine ratio observed in sKOA compared to that of pKOA. The CombiROC curves identified TNF-α, IL-1β, IL-6 and NOx as the best performing panel of potential diagnostic markers to discriminate pKOA from control groups (~97% accuracy, 90% Sensitivity [SE] and 98% specificity [SP]), while TNF-α, IL-1β and IL-6 discriminated sKOA from control groups (~100% accuracy, 100% SE, and 98% SP). The study identified discrete serum immune biomarker panels to differentiate between pKOA (TNF-α, IL-1β, IL-6 and NOx) and sKOA (TNF-α, IL-1β and IL-6). These findings may assist in developing distinct therapeutic agents for the two types of KOA.

Inflammatory factors are crucial for the pathogenesis of post-traumatic osteoarthritis confirmed by a novel porcine model: "Idealized" anterior cruciate ligament reconstruction" and gait analysis

OBJECTIVE

To determine whether idealized anterior cruciate ligament reconstruction (IACL-R) restores normal gait features, and whether inflammatory factors are involved in the pathogenesisof post-traumatic osteoarthritis (PTOA).

METHODS

Fourteen mature female minipigs were allocated to a sham group (n = 7) or an IACL-R group (n = 7). Load asymmetry during gait was recorded using a pressure-sensing walkway measurement system to evaluate the gait features of the right knee joint before and after surgery. Inflammatory factors (including interleukin [IL]-1α, IL-1β, IL-2, IL-6, IL-8, IL-18, tumor necrosis factor-α, and granulocyte-macrophage colony-stimulating factor) in synovial fluid were measured using Luminex assays before and after surgery. Cartilage integrity and the subchondral bone plate of the right knee were evaluated using histology and imaging at 3 months postoperatively.

RESULTS

Swing time and stance time returned to their preoperative values on day 31, while maximum force, contact area, peak force ,and impulse returned to their preoperative values on day 45 after the surgery in the IACL-R group (P = 0.073, 0.053, 0.107, 0.052, 0.152, and 0.059, respectively).Thus, IACL-R restored normal gait. Compared with their preoperative concentrations, all tested inflammatory factors showed significantly increased concentrations in the synovial fluid in the IACL-R group, especially at 3, 7, and 15 days postoperatively. X-ray, computed tomography, magnetic resonance imaging, and histological data showed severe cartilage damage in the IACL-R model.

CONCLUSION

IACL-R restored normal gait features but caused significant cartilage damage, indicating that significantly elevated inflammatory factors maybe crucial for the pathogenesis of PTOA.

Serum progranulin to TNF-α ratio in patients with gonarthrosis

OBJECTIVE

Progranulin (PGRN) is a growth factor that has antiinflammatory, immunosuppressive, and chondroprotective effects. It blocks Tumor Necrosis Factor-α (TNF-α) signal pathway by binding its receptor. Recently, it has been claimed that PGRN may be overexpressed in patients with Osteoarthritis (OA). However, these patients tend to be obese and obesity also may be one of the factors that affect PGRN levels. The aim of this study was to compare the PGRN levels of patients with Knee OA (KOA) with that of healthy controls by eliminating the effect of obesity and to evaluate PGRN-to-Tumor Necrosis Factor-α (TNF-α) ratio in KOA, both of which were investigated first in literature by this study.

METHODS

A total of 80 individuals (40 patients with KOA and 40 healthy controls) were included in this study. The patients and controls were divided into two groups according to their Body Mass Indexes (BMI): nonobese (BMI between 18.5 and 24.9) and obese (BMI of 30 or higher). Each of the groups included 20 subjects and had an equal number of men and women. Blood samples were obtained from all participants, and the serum PGRN and TNF-α levels were measured using commercial ELISA kits.

RESULTS

There was no difference among groups in terms of age (P = 0.416) and gender distribution. There was no statistical difference among study groups with regard to serum PGRN levels. Serum TNF-α levels were significantly higher in obese controls (P < 0.001) and nonobese patients (P = 0.003) compared to that of nonobese healthy controls. Correspondingly, serum PGRN-to-TNF-α ratio was considerably lower in obese controls (P < 0.001) and nonobese patients (P < 0.001) by comparison with that of nonobese healthy controls.

CONCLUSION

We determined that both obesity and KOA increased serum TNF-α levels and concordantly decreased serum PGRNto- TNF-α ratio. The results of the study suggest that the activation of the PGRN pathway and/or the inhibition of the TNFα pathway may be essential in terms of the reestablishment of the disrupted inflammatory balance in patients with KOA.

LEVEL OF EVIDENCE

Level III, Diagnostic study.

Association of Gut Microbiome and Vitamin D Deficiency in Knee Osteoarthritis Patients: A Pilot Study

BACKGROUND

Few preclinical studies have shown that Knee osteoarthritis (KOA) is linked to gut microbiome dysbiosis and chronic inflammation. This pilot study was designed to look at the gut microbiome composition in KOA patients and normal individuals with or without vitamin D deficiency (VDD, serum vitamin D <30 ng/mL).

METHODS

This pilot study was conducted prospectively in 24 participants. The faecal samples of all the participants were taken for DNA extraction. The V3-V4 region of 16s rRNA was amplified, and the library was prepared and sequenced on the Illumina Miseq platform.

RESULTS

The mean (±SD) age was 45.5 (±10.2) years with no defined comorbidities. Of 447 total Operational Taxonomic Units (OTUs), a differential abundance of 16 nominally significant OTUs between the groups was observed. Linear discriminate analysis (LEfSe) revealed a significant difference in bacteria among the study groups. Pseudobutyrivibrio and Odoribacter were specific for VDD, while Parabacteroides, Butyricimonas and Gordonibacter were abundant in the KOA_VDD group, and Peptococcus, Intestimonas, Delftia and Oribacterium were abundant in the KOA group. About 80% of bacterial species were common among different groups and hence labelled as core bacterial species. However, the core microbiome of KOA and VDD groups were not seen in the KOA_VDD group, suggesting that these bacterial groups were affected by the interaction of the KOA and VDD factors.

CONCLUSION

Parabacteroides, Butyricimonas, Pseudobutyrivibrio, Odoribacter and Gordonibacter are the predominant bacteria in vitamin D deficient patients with or without KOA. Together these results indicate an association between the gut microbiome, vitamin D and knee osteoarthritis.

Potential Mechanism of Action of Current Point-of-Care Autologous Therapy Treatments for Osteoarthritis of the Knee-A Narrative Review

Osteoarthritis (OA) is a progressive degenerative disease that manifests as pain and inflammation and often results in total joint replacement. There is significant interest in understanding how intra-articular injections made from autologous blood or bone marrow could alleviate symptoms and potentially intervene in the progression of the disease. There is in vitro an in vivo evidence that suggests that these therapies, including platelet-rich plasma (PRP), autologous anti-inflammatories (AAIs), and concentrated bone marrow aspirate (cBMA), can interrupt cartilage matrix degradation driven by pro-inflammatory cytokines. This review analyzes the evidence for and against inclusion of white blood cells, the potential role of platelets, and the less studied potential role of blood plasma when combining these components to create an autologous point-of-care therapy to treat OA. There has been significant focus on the differences between the various autologous therapies. However, evidence suggests that there may be more in common between groups and perhaps we should be thinking of these therapies on a spectrum of the same technology, each providing significant levels of anti-inflammatory cytokines that can be antagonists against the inflammatory cytokines driving OA symptoms and progression. While clinical data have demonstrated symptom alleviation, more studies will need to be conducted to determine whether these preclinical disease-modifying findings translate into clinical practice.

Loganin ameliorates cartilage degeneration and osteoarthritis development in an osteoarthritis mouse model through inhibition of NF-κB activity and pyroptosis in chondrocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Corni Fructus (CF), the red fruit of Cornus officinalis Siebold & Zucc, has been used both as food and medicinal herb in traditional Chinese medicine (TCM). Loganin is a major iridoid glycoside and one of the quality control indexes of CF. In TCM clinical practice, prescription containing CF is commonly used to treat osteoarthritis (OA), but the underlying mechanisms of loganin are not yet utterly understood.

AIM OF THE STUDY

The aims of the present study are to confirm the therapeutic effects of loganin in an OA mouse model and to determine the mechanisms involved in the OA protective effects.

MATERIALS AND METHODS

The destabilization of the medial meniscus (DMM) procedure was performed on the right knee of 8-week-old C57BL/6 male mice. 30 or 100 μg/ml of loganin was then injected into articular space twice a week for 8 and 12-week. Safranin O/Fast green staining, H&E staining, micro-CT analysis were performed to analyze structural and morphological changes. The protein expression of collagen type II (Col2), metalloproteinase-3 (Mmp3), matrix metalloproteinase 13 (Mmp13) collagen type X (Col10), cryopyrin and caspase-1 were detected by immunochemistry staining. Immuno-fluorescence assay was performed to assess changes in expression of CD31, endomucin, p65 and p-I-κB.

RESULTS

Results of histomorphometry showed that loganin delays the progression of OA in the DMM model. In cartilage, loganin decreased the OARSI score, increasing hyaline cartilage (HC) thickness and decreasing calcified cartilage (CC) thickness. Moreover, loganin inhibited osteophyte formation, reduced the bone volume fraction (BV/TV), lowered trabecular thickness (Tb.Th) and increased trabecular separation (Tb.Sp) in subchondral bone. Mechanistically, loganin increased the expressions of Col2, decreases the expression of Mmp3, Mmp13, Col10, cryopyrin and caspase-1 in cartilage. In parallel, loganin inhibited the expression of CD31 and endomucin in subchondral bone. Furthermore, loganin suppressed nuclear translocation of p65 protein, and decreased the amount of p-I-κB in chondrocytes.

CONCLUSIONS

In summary, these results uncovered that loganin inhibits NF-κB signaling and attenuates cartilage matrix catabolism and pyroptosis of chondrocytes in articular cartilage. Loganin may serve as a potential therapeutic agent for OA treatment.

[Increased proportion and abnormal phenotype of NK cells in peripheral blood of patients with knee osteoarthritis]

Objective To investigate the distribution and phenotypic characteristics of natural killer (NK) cells in the peripheral blood of knee osteoarthritis (KOA) patients. Methods Flow cytometry was used to detect and compare the distribution of NK cells and the expression of their surface functional receptors in the peripheral blood of healthy controls without KOA and patients with KOA, such as human leukocyte antigen DR (HLA-DR) and natural cytotoxicity receptor 3 (NCR3/NKP30). Results The proportion of NK cells in the peripheral blood of KOA patients was significantly up-regulated, especially CD16bright NK cells. The expression of HLA-DR molecules on the surface of NK cells with KOA was up-regulated, while the expression of NKP30 was significantly down-regulated. Conclusion The proportion of NK cells in the peripheral blood of KOA patients increases, and the cells show the up-regulated expression of CD16 and HLA-DR and the down-regulated expression of NKP30.

Efficacy and safety of duloxetine in osteoarthritis: a systematic review and meta-analysis

About 21% of adults with osteoarthritis (OA) are diagnosed with concomitant depression in addition to chronic pain. Duloxetine, an anti-depressant medication, has been recently approved for managing Knee OA. We performed a systematic review to ascertain the efficacy and safety of duloxetine for OA. We searched MEDLINE, EMBASE, Web of Science, Google Scholar, and the Cochrane Database from inception to December 2018. Randomized clinical trials (RCTs) assessing the efficacy and/or safety of duloxetine versus placebo in OA patients were included. Data extraction and quality assessment were undertaken by two independent reviewers. Seven RCTs (n = 2,102 participants) met our inclusion criteria, and five RCTs (n = 1,713) were eligible for meta-analysis. The results of our analyses indicate that duloxetine has statistically significant, moderate benefits on pain, function, and quality of life in knee OA patients for up to 13 weeks. Reported incidences of gastrointestinal adverse events were three to four times higher in participants who received duloxetine versus placebo. Duloxetine may be an effective treatment option for individuals with knee OA, but use of the drug is associated with a significantly higher risk of adverse events. Patient preferences and clinicians' judgment must be considered before the initiation of duloxetine.

Synovial fluid monocyte/macrophage subsets and their correlation to patient-reported outcomes in osteoarthritic patients: a cohort study

BACKGROUND

Chronic, low-grade inflammation of the synovium (synovitis) is a hallmark of osteoarthritis (OA), thus understanding of OA immunobiology, mediated by immune effectors, is of importance. Specifically, monocytes/macrophages (MΦs) are known to be abundantly present in OA joints and involved in OA progression. However, different subsets of OA MΦs have not been investigated in detail, especially in terms of their relationship with patient-reported outcome measures (PROMs). We hypothesized that levels of synovial fluid (SF) MΦ subsets are indicative of joint function and quality of life in patients with OA, and can therefore serve as biomarkers and therapeutic targets for OA.

METHODS

In this cohort study, synovial fluid leukocytes (SFLs, N = 86) and peripheral blood mononuclear cells (n = 53) from patients with knee OA were characterized. Soluble MΦ receptors and chemokine (sCD14, sCD163, CCL2, CX3CL1) levels were detected in SF using immunoassays. Linear models, adjusted for sex, age and body mass index, were used to determine associations between SF MΦs and soluble factors with PROMs (N = 83). Pearson correlation was calculated to determine correlation between MΦ subsets, T cells and soluble factors.

RESULTS

SF MΦs were the most abundant SFLs. Within these, the double-positive CD14+CD16+-MΦ subset is enriched in knee OA SF compared to the circulation. Importantly, MΦ subset ratios correlated with PROMs, specially stiffness, function and quality of life. Interestingly, the SF CD14+CD16+-MΦ subset ratio correlated with SF chemokine (C-C motif) ligand 2 (CCL2) levels but not with levels of sCD163 or sCD14; we found no association between PROMs and either SF CCL2, sCD163, sCD14 or CX3CL1 (which was below detection levels). All SF MΦs displayed high levels of HLA-DR, suggesting an activated phenotype. Correlation between OA SF MΦ subsets and activated CD4+ T cell subsets suggests modulation of CD4+ T cell activation by MΦs.

CONCLUSION

SF MΦ subsets are associated with knee OA PROMs and display an activated phenotype, which may lead to modulation of CD4+ T cell activation. Knee OA SF MΦ subsets could serve as knee OA function biomarkers and as targets of novel therapeutics.

Conditional Macrophage Depletion Increases Inflammation and Does Not Inhibit the Development of Osteoarthritis in Obese Macrophage Fas-Induced Apoptosis-Transgenic Mice

OBJECTIVE

To investigate whether short-term, systemic depletion of macrophages can mitigate osteoarthritis (OA) following injury in the setting of obesity.

METHODS

CSF-1R-GFP+ macrophage Fas-induced apoptosis (MaFIA)-transgenic mice that allow conditional depletion of macrophages were placed on a high-fat diet and underwent surgery to induce knee OA. A small molecule (AP20187) was administrated to deplete macrophages in MaFIA mice. The effects of macrophage depletion on acute joint inflammation, OA severity, and arthritic bone changes were evaluated using histology and micro-computed tomography. Immunohistochemical analysis was performed to identify various immune cells. The levels of serum and synovial fluid cytokines were also measured.

RESULTS

Macrophage-depleted mice had significantly fewer M1 and M2 macrophages in the surgically operated joints relative to controls and exhibited decreased osteophyte formation immediately following depletion. Surprisingly, macrophage depletion did not attenuate the severity of OA in obese mice; instead, it induced systemic inflammation and led to a massive infiltration of CD3+ T cells and particularly neutrophils, but not B cells, into the injured joints. Macrophage-depleted mice also demonstrated a markedly increased number of proinflammatory cytokines including granulocyte colony-stimulating factor, interleukin-1β (IL-1β), IL-6, IL-8, and tumor necrosis factor in both serum and joint synovial fluid, although the mice showed a trend toward decreased levels of insulin and leptin in serum after macrophage depletion.

CONCLUSION

Our findings indicate that macrophages are vital for modulating homeostasis of immune cells in the setting of obesity and suggest that more targeted approaches of depleting specific macrophage subtypes may be necessary to mitigate inflammation and OA in the setting of obesity.

Strawberries Improve Pain and Inflammation in Obese Adults with Radiographic Evidence of Knee Osteoarthritis

Osteoarthritis (OA), the most common form of arthritis, is a significant public health burden in U.S. adults. Among its many risk factors, obesity is a key player, causing inflammation, pain, impaired joint function, and reduced quality of life. Dietary polyphenols and other bioactive compounds in berries, curcumin, and tea have shown effects in ameliorating pain and inflammation in OA, but few clinical studies have been reported. The purpose of the present study was to examine the effects of dietary strawberries on pain, markers of inflammation, and quality of life indicators in obese adults with OA of the knee. In a randomized, double-blind cross-over trial, adults with radiographic evidence of knee OA (n = 17; body mass index (BMI): (mean ± SD) 39.1 ± 1.5; age (years): 57 ± 7) were randomized to a reconstituted freeze-dried strawberry beverage (50 g/day) or control beverage daily, each for 12 weeks, separated by a 2-week washout phase (total duration, 26 weeks). Blood draws and assessments of pain and quality of life indicators were conducted using the Visual Analog Scale for Pain (VAS Pain), Measures of Intermittent and Constant Osteoarthritis Pain (ICOAP), and Health Assessment Questionnaire-Disability Index (HAQ-DI) questionnaires, which were completed at baseline and at weeks 12, 14, and 26 of the study. Among the serum biomarkers of inflammation and cartilage degradation, interleukin (IL)-6, IL-1β, and matrix metalloproteinase (MMP)-3 were significantly decreased after strawberry vs. control treatment (all p < 0.05). Strawberry supplementation also significantly reduced constant, intermittent, and total pain as evaluated by the ICOAP questionnaire as well as the HAQ-DI scores (all p < 0.05). No effects of treatment were noted on serum C-reactive protein (CRP), nitrite, glucose, and lipid profiles. Dietary strawberries may have significant analgesic and anti-inflammatory effects in obese adults with established knee OA.

Presence of IL-17 in synovial fluid identifies a potential inflammatory osteoarthritic phenotype

Purpose

Osteoarthritis (OA) is a common and heterogeneous arthritic disorder. Patients suffer pain and their joints are characterized by articular cartilage loss and osteophyte formation. Risk factors for OA include age and obesity with inflammation identified as a key mediator of disease pathogenesis. Interleukin-17A (IL-17) is a pro-inflammatory cytokine that has been implicated in inflammatory diseases such as rheumatoid arthritis. IL-17 can upregulate expression of inflammatory cytokines and adipocytokines. The aim of this study was to evaluate IL-17 levels in the synovial fluid of patients with end-stage knee and hip OA in relation to inflammation- and pain-related cytokines and adipocytokines in synovial fluid and serum, and clinical and radiographic disease parameters.

Methods

This is a cross-sectional study of 152 patients undergoing total hip and knee arthroplasty for OA. IL-17, IL-6, leptin, adiponectin, visfatin, resistin, C-C Motif Chemokine Ligand 2 (CCL2), C-C Motif Chemokine Ligand 7 (CCL7) and nerve growth factor (NGF) protein levels were measured in synovial fluid and serum using enzyme-linked immunosorbent assay (ELISA). Baseline characteristics included age, sex, body mass index, co-morbidities, pain and function, and radiographic analyses (OA features, K&L grade, minimal joint space width).

Results

14 patients (9.2%) had detectable IL-17 in synovial fluid. These patients had significantly higher median concentrations of IL-6, leptin, resistin, CCL7 and NGF. Osteophytes, sclerosis and minimum joint space width were significantly reduced in patients with detectable IL-17 in synovial fluid. No differences were found in pain, function and comorbidities. IL-17 concentrations in synovial fluid and serum were moderately correlated (r = 0.482).

Conclusion

The presence of IL-17 in the synovial fluid therefore identifies a substantial subset of primary end-stage OA patients with distinct biological and clinical features. Stratification of patients on the basis of IL-17 may identify those responsive to therapeutic targeting.

Epigallocatechin-3-O-gallate modulates global microRNA expression in interleukin-1β-stimulated human osteoarthritis chondrocytes: potential role of EGCG on negative co-regulation of microRNA-140-3p and ADAMTS5

PURPOSE

MicroRNAs (miRNAs) are short, non-coding RNAs involved in almost all cellular processes. Epigallocatechin-3-O-gallate (EGCG) is a green tea polyphenol and is known to exert anti-arthritic effects by inhibiting genes associated with osteoarthritis (OA). This study was undertaken to investigate the global effect of EGCG on interleukin-1β (IL-1β)-induced expression of miRNAs in human chondrocytes.

METHODS

Human chondrocytes were derived from OA cartilage and then treated with EGCG and IL-1β. Human miRNA microarray technology was used to determine the expression profile of 1347 miRNAs. Microarray results were verified by taqman assays and transfection of chondrocytes with miRNA inhibitors.

RESULTS

Out of 1347 miRNAs, EGCG up-regulated expression of 19 miRNAs and down-regulated expression of 17 miRNAs, whereas expression of 1311 miRNAs remains unchanged in IL-1β-stimulated human OA chondrocytes. Bioinformatics approach showed that 3`UTR of ADAMTS5 mRNA contains the 'seed-matched-sequence' for hsa-miR-140-3p. IL-1β-induced expression of ADAMTS5 correlated with down-regulation of hsa-miR-140-3p. Importantly, EGCG inhibited IL-1β-induced ADAMTS5 expression and up-regulated the expression of hsa-miR-140-3p. This EGCG-induced co-regulation between ADAMTS5 and hsa-miR-140-3p becomes reversed in OA chondrocytes transfected with anti-miR-140-3p.

CONCLUSIONS

This study provides an important insight into the molecular basis of the reported anti-arthritic effects of EGCG. Our data indicate that the potential of EGCG in OA chondrocytes may be related to its ability to globally inhibit inflammatory response via modulation of miRNAs expressions.

The effect of pomegranate juice on clinical signs, matrix metalloproteinases and antioxidant status in patients with knee osteoarthritis

BACKGROUND

Osteoarthritis (OA) is one of the commonest forms of musculoskeletal disorders that leads to joint degeneration and has a major impact on patients' quality of life. Experimental and in vitro studies have suggested the protective roles of pomegranate juice (PJ) as a rich antioxidant source for mitigating cartilage inflammation. In this interventional study, 38 patients with knee OA were randomly divided into two groups: PJ or control for 6 weeks to evaluate the effect of this intervention on clinical signs, inflammation and antioxidant status.

RESULTS

Significant decreases in Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) total score (P = 0.01), stiffness score (P = 0.00) and physical function score (P = 0.01) were observed in PJ group after the intervention. The means of serum levels of matrix metalloproteinase (MMP)-13 was significantly decreased (P = 0.02) and glutathione peroxidase was increased in the intervention group compared with the control group after the study period (P = 0.02).

CONCLUSIONS

According to the findings of this clinical trial, PJ consumption can improve physical function and stiffness, decrease breakdown cartilage enzymes and increase antioxidant status in patients with knee OA. © 2016 Society of Chemical Industry.

Expression profile of cytokines and chemokines in osteoarthritis patients: Proinflammatory roles for CXCL8 and CXCL11 to chondrocytes

There are interactions between immune response and destruction of articular cartilage/synovial tissue in osteoarthritis (OA), which leads to chronic inflammation and systemic failure of joints. However, the role of immunological factors in the pathogenesis of OA has not been fully elucidated. In this study, expressions of 47 cytokines and chemokines were tested in the peripheral bloods and synovial fluids from 13 normal controls (NCs) and 31 OA patients. The primary chondrocytes, which were isolated from cartilages of OA patients, were stimulated by recombinant CXCL8 and CXCL11 to analyze the proliferation, cytokine secretion, and signaling pathways. The levels of IL-17A, CXCL8, CXCL9, and CXCL11 were elevated in the serum and synovial fluids of OA patients. Moreover, expressions of CXCL8 and CXCL11 were remarkably increased in the synovial fluids of late stage OA. Stimulation of CXCL8/11 resulted in the reduction of primary chondrocytes proliferation with downregulation of G2-M stage but elevation of S stage and apoptosis cells. The secretions of proinflammatory cytokines and MMPs were also increased upon stimulation. Furthermore, CXCL8/11 stimulation induced the higher expressions of phosphorylated STAT3, NF-kB p50 and JNK, but not p38MAPK or ERK1/2. Our findings suggested that CXCL8 and CXCL11 promoted the apoptosis and suppressed the proliferation of chondrocytes probably via influencing JAK-STAT, NF-kB and JNK MAPK signaling pathway and enhancing the expressions of other proinflammatory cytokines. CXCL8/11 may aggravate the disease progression of OA, and may also be served as new therapeutic targets for treatment of OA.

Effect of Mud-Bath Therapy on Serum Biomarkers in Patients with Knee Osteoarthritis: Results from a Randomized Controlled Trial

BACKGROUND

Balneotherapy is one of the most commonly used non-pharmacological approaches for osteoarthritis (OA). Recent data indicate that some biomarkers could be useful to predict OA progression and to assess therapeutic response.

OBJECTIVES

To evaluate the effects of mud-bath therapy on serum biomarkers in patients with knee OA.

METHODS

The study group comprised 103 patients with primary symptomatic bilateral knee OA who were randomly assigned to receive a cycle of mud-bath therapy over a period of 2 weeks or to continue their standard therapy alone. Clinical and biochemical parameters were assessed at baseline and after 2 weeks. Clinical assessments included global pain score on a visual analogue scale (VAS) and the Western Ontario and McMaster Universities Index (WOMAC) subscores for knee OA. Cartilage oligomeric matrix protein (COMP), C-terminal cross-linked telopeptide type II collagen (CTX-II), myeloperoxidase (MPO) and high sensitivity C-reactive protein (hsCRP) serum levels were assessed by ELISA.

RESULTS

At the end of mud-bath therapy we observed a statistically significant improvement in VAS and WOMAC subscores. Serum levels of COMP, MPO and hsCRP did not show any significant modification in either group, while a significant increase (P < 0.001) in CTX-II serum levels was observed in the mud-bath group after the treatment.

CONCLUSIONS

A cycle of mud-bath therapy added to the usual treatment had a beneficial effect on pain and function in patients with knee OA. The evaluation of serum biomarkers showed a significant increase of CTX-II only, perhaps due to an increase of cartilage turnover induced by thermal stress.

A double-blind, placebo-controlled, randomised, clinical study on the effectiveness of collagen peptide on osteoarthritis

BACKGROUND

Recent studies show that enzymatically hydrolysed collagen, the collagen peptide, is absorbed and distributed to joint tissues and has analgesic and anti-inflammatory properties. A double-blind, placebo-controlled, randomised trial with collagen peptides isolated from pork skin (PCP) and bovine bone (BCP) sources was carried out to study the effectiveness of orally supplemented collagen peptide to control the progression of osteoarthritis in patients diagnosed with knee osteoarthritis. Improvement in treatment was assessed with reduction in Western Ontario McMaster Universities (WOMAC), visual analogue scale (VAS) and quality of life (QOL) scores from baseline to 13 weeks (Visit 7). Safety and tolerability were also evaluated.

RESULTS

There was significant reduction from baseline to Visit 7 in the primary end points of WOMAC and VAS scores and in the secondary end point of QOL score in subjects with PCP and BCP groups, while in subjects with placebo group the end point indices remained unaltered. Furthermore, all the score levels of WOMAC, VAS and QOL decreased significantly (P < 0.01) in the study group compared to placebo group in Visit 7.

CONCLUSION

The study demonstrated that collagen peptides are potential therapeutic agents as nutritional supplements for the management of osteoarthritis and maintenance of joint health.

The effect of sodium hyaluronate treating knee osteoarthritis on synovial fluid interleukin -1β and clinical treatment mechanism

In order to explore the influence of sodium hyaluronate on knee osteoarthritis (KOA) patients synovial fluid interleukin -1β (IL-1β) and analyze its clinical mechanism, this study analyzed 40 cases of KOA patients in our hospital's orthopaedic department, randomly divided them into two groups: Sodium hyaluronate group (group A) and normal saline group (group B), each consists 20 patients. Besides, we selected another 20 patients as normal control group. Group A treated knee joint cavity by injecting sodium hyaluronate, and group B injected knee joint cavity in equal amount of normal saline, once a week for five weeks. Collect respectively knee joint synovial fluid in patients of group A and group B before treatment and after five weeks of treatment, detect the content of knee joint synovial fluid IL-1βin of all the three groups by using enzyme linked immunosorbent assay (ELISA). We can conclude that (1) IL-1β content of knee joint synovial fluid in KOA patients before treatment was significantly higher than healthy people; (2) IL-1β content of group A knee joint synovial fluid after treatment was significantly reduced than before treatment, there was no significant difference for group BIL-1β content before and after treatment; (3) there was no significant difference between group A knee joint synovial fluid IL-1β content after treatment and healthy people. Thus it can be proved that content of IL-1β in knee joint synovial fluid KOA patients is higher than healthy people; sodium hyaluronate can reduce the content of IL-1β in synovial joints and can be effective in the treatment of knee osteoarthritis.

Effects of an exercise therapy protocol on inflammatory markers, perception of pain, and physical performance in individuals with knee osteoarthritis

Establishing prevention and therapeutic strategies for osteoarthritis (OA) is necessary to minimize functional disability and the impact of the disease on society. The aim of this study was to determine the effects of an exercise therapy protocol on inflammatory markers, perception of pain, and physical performance in individuals with OA of the knee. The protocol consisted of flexibility training and muscle strengthening over 12 weeks with three 80-min sessions per week. Peripheral blood was collected to determine serum levels of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and soluble forms of the TNF-α receptor (sTNFR1 and sTNFR2). A clinical assessment of the musculoskeletal system and Western Ontario and McMaster Universities (WOMAC) questionnaire were applied to evaluate the specific symptoms of knee OA. Pain intensity was evaluated using a visual analog scale (VAS). All measurements were taken before and after the intervention. Twenty-two individuals (mean age 58.8 ± 6.4 years) completed the protocol. A decrease in the perception of pain was evident on VAS (p < 0.001) and pain subscale of the WOMAC (p < 0.001). In addition, there was a reduction in serum levels of IL-6 (p < 0.001). However, changes in the levels of the TNF-α and its soluble receptors were not statistically significant. Physical function subscale score and the WOMAC global score improved significantly (p < 0.001). The training also promoted an increase in the progression load for all muscles groups analyzed (p < 0.001). Our data suggest that the exercise therapy protocol could be a strategy for reducing IL-6 levels, managing pain, and improving function in individuals with OA of the knee. However, more studies are necessary to investigate the issue.

Cordycepin modulates inflammatory and catabolic gene expression in interleukin-1beta-induced human chondrocytes from advanced-stage osteoarthritis: an in vitro study

Cordycepin is widely used as for its various pharmacological activities, such as anti-inflammation, anti-angiogenesis, anti-aging, anti-tumor and anti-proliferation. However, the precise role of cordycepin on chondrocytes is not clear. In the present study, we examined the inhibitory effects of cordycepin on interleukin-1 beta (IL-1β)-induced glycosaminoglycan (GAG) release, nitric oxide production as well as gene expressions of inflammatory and catabolic mediators in human cartilage and chondrocytes. Cartilage explants and human chondrocytes were cultured in the absence or in the presence of IL-1β (10 ng/ml) and with or without cordycepin (5-100 μM). GAG content in the cartilage explants was measured by using the dimethylmethylene blue method and Safranin O staining. Nitric oxide level was determined by Griess reaction. Expressions of MMP-1, MMP-13, cathepsin K, cathepsin S, ADAMTS-4 (a disintegrin and metalloproteinase with thrombospondin motifs-4) and ADAMTS-5, inducible nitric oxide synthase (iNOS) and cyclooxgenase-2 (COX-2) were evaluated by real-time quantitative PCR. We found that cordycepin suppressed IL-1β-stimulated GAG release. Gene expressions of catabolic enzymes, including MMP-1, MMP-13, cathepsin K, cathepsin S, ADAMTS-4 and ADAMTS-5, were decreased by cordycepin in a dose-dependent manner. In addition, cordycepin inhibited IL-1β-induced COX-2 and iNOS expression at the transcript level as well as blocked NO production. Our results suggest that cordycepin may possess chondroprotective effect by preventing cartilage denegation and interfering inflammatory response in the pathogenesis of OA.

Decoy receptor 3 suppresses B cell functions and has a negative correlation with disease activity in rheumatoid arthritis

OBJECTIVES

The decoy receptor 3 (DcR3) is a member of the tumour necrosis factor (TNF) receptor superfamily and may regulate inflammation. The aim of this study was to investigate the role of DcR3 in B cell functions and its correlation to disease activity in patients with rheumatoid arthritis (RA).

METHODS

The concentrations of DcR3 and TNF-α were measured by ELISA. B cell proliferation was assessed by quantification of 3H-thymidine uptake. Staphylococcus aureus Cowan (SAC) strain were used to stimulate B cell proliferation and TNF-α production.

RESULTS

Compared to the osteoarthritis (OA) patients, the RA group had higher synovial DcR3 levels (3273.6±1623.2 vs. 1594.8±1190.0 pg/ml, p=0.003), which were negatively correlated with the serum erythrocyte sedimentation rate and Disease Activity Score using 28 joint counts (DAS28) scores (r=-0.560, p=0.002; r=-0.579, p<0.001, respectively). Although the RA B cells have more active characteristics, B cell proliferation induced by SAC was successfully suppressed by recombinant DcR3.Fc fusion protein with an average inhibition of 44.8%. Moreover, DcR3.Fc fusion protein was found to suppress SAC-induced TNF-α production by B cells in 8 RA patients (average inhibition 47.0%).

CONCLUSIONS

The results of our study indicated that the inhibition of B cell functions by DcR3 may partially explain the negative correlation between DcR3 level and disease activity in RA patients. Our findings imply that DcR3 may be used as a biomarker for disease activity and a potential therapeutic agent in the treatment of RA.

Effects of intensive diet and exercise on knee joint loads, inflammation, and clinical outcomes among overweight and obese adults with knee osteoarthritis: the IDEA randomized clinical trial

IMPORTANCE

Knee osteoarthritis (OA), a common cause of chronic pain and disability, has biomechanical and inflammatory origins and is exacerbated by obesity.

OBJECTIVE

To determine whether a ≥10% reduction in body weight induced by diet, with or without exercise, would improve mechanistic and clinical outcomes more than exercise alone.

DESIGN, SETTING, AND PARTICIPANTS

Single-blind, 18-month, randomized clinical trial at Wake Forest University between July 2006 and April 2011. The diet and exercise interventions were center-based with options for the exercise groups to transition to a home-based program. Participants were 454 overweight and obese older community-dwelling adults (age ≥55 years with body mass index of 27-41) with pain and radiographic knee OA.

INTERVENTIONS

Intensive diet-induced weight loss plus exercise, intensive diet-induced weight loss, or exercise.

MAIN OUTCOMES AND MEASURES

Mechanistic primary outcomes: knee joint compressive force and plasma IL-6 levels; secondary clinical outcomes: self-reported pain (range, 0-20), function (range, 0-68), mobility, and health-related quality of life (range, 0-100).

RESULTS

Three hundred ninety-nine participants (88%) completed the study. Mean weight loss for diet + exercise participants was 10.6 kg (11.4%); for the diet group, 8.9 kg (9.5%); and for the exercise group, 1.8 kg (2.0%). After 18 months, knee compressive forces were lower in diet participants (mean, 2487 N; 95% CI, 2393 to 2581) compared with exercise participants (2687 N; 95% CI, 2590 to 2784, pairwise difference [Δ](exercise vs diet )= 200 N; 95% CI, 55 to 345; P = .007). Concentrations of IL-6 were lower in diet + exercise (2.7 pg/mL; 95% CI, 2.5 to 3.0) and diet participants (2.7 pg/mL; 95% CI, 2.4 to 3.0) compared with exercise participants (3.1 pg/mL; 95% CI, 2.9 to 3.4; Δ(exercise vs diet + exercise) = 0.39 pg/mL; 95% CI, -0.03 to 0.81; P = .007; Δ(exercise vs diet )= 0.43 pg/mL; 95% CI, 0.01 to 0.85, P = .006). The diet + exercise group had less pain (3.6; 95% CI, 3.2 to 4.1) and better function (14.1; 95% CI, 12.6 to 15.6) than both the diet group (4.8; 95% CI, 4.3 to 5.2) and exercise group (4.7; 95% CI, 4.2 to 5.1, Δ(exercise vs diet + exercise) = 1.02; 95% CI, 0.33 to 1.71; P(pain) = .004; 18.4; 95% CI, 16.9 to 19.9; Δ(exercise vs diet + exercise), 4.29; 95% CI, 2.07 to 6.50; P(function )< .001). The diet + exercise group (44.7; 95% CI, 43.4 to 46.0) also had better physical health-related quality of life scores than the exercise group (41.9; 95% CI, 40.5 to 43.2; Δ(exercise vs diet + exercise) = -2.81; 95% CI, -4.76 to -0.86; P = .005).

CONCLUSIONS AND RELEVANCE

Among overweight and obese adults with knee OA, after 18 months, participants in the diet + exercise and diet groups had more weight loss and greater reductions in IL-6 levels than those in the exercise group; those in the diet group had greater reductions in knee compressive force than those in the exercise group.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00381290.

[Xinfeng Capsule improves cardiopulmonary function of knee osteoarthritis rats by BTLA-HVEM signaling pathway to induce Treg immune tolerance]

AIM

To observe the effects of Xinfeng Capsule (XFC) on cardiopulmonary function of knee osteoarthritis (KOA) rats and explore its molecular mechanism.

METHODS

Forty rats were randomly divided into normal control (NC) group, model control (MC) group, glucosamine control (GS) group and XFC group, 10 in each group. All rats were induced to KOA by injected papain and L-Cys into the right knee joint except NC group. Fourteen days after modeling, NC and MC groups were given normal saline (0.01 g/kg), GS and XFC groups were given glucosamine (0.098 g/kg) and XFC suspension (0.375 g/kg), respectively. Cardiac and pulmonary function were detected by ultrasonography and animal spirometry, respectively. B and T lymphocyte attenuator (BTLA), herpesvirus entry mediator (HVEM), interleukin (IL)-17, IL-4, transforming growth factor-beta (TGF-β1) were detected by ELISA; CD4(+);CD25(+);Treg and CD4(+); CD25(+);Foxp3(+); Treg were detected by flow cytometry.

RESULTS

Compared with NC group, body mass, levels of early diastolic peak flow velocity (E), early diastolic peak flow velocity/atrial peak flow velocity (E/A), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), 25% forced expiratory flow (FEF25), 50% forced expiratory flow (FEF50), 75% forced expiratory flow (FEF75), maximal mid-expiratory flow (MMF), peak expiratory flow (PEF), expressions of BTLA, HVEM, IL-4, CD4(+);CD25(+);Treg and CD4(+);CD25(+);Foxp3(+); Treg significantly decreased, and TGF-β1, IL-17 significantly increased in MC group (P<0.01 or P<0.05). Compared with MC group, weight, levels of E, E/A, FEV1, FEF50, FEF75, PEF, BTLA, HVEM, IL-4, CD4(+);CD25(+);Treg and CD4(+);CD25(+);Foxp3(+); Treg significantly increased, and Mankin score, cardiacindex (CI), lung index (LI), TGF-β1, IL-17 significantly decreased in GS and XFC groups (P<0.01 or P<0.05); Compared with GS group, weight and Treg were significantly elevated in XFC group (P<0.01 or P<0.05).

CONCLUSION

XFC can decrease Mankin scores of cartilage and improve cardiopulmonary function of KOA rats. Its mechanism may be enhancing BTLA-HVEM negative co-stimulatory signals, inducing Treg immune tolerance, up-regulating IL-4, down-regulating IL-17, TGF-β1, then to inhibit abnormal inflammatory immune response.

Anti-inflammatory effects of low-dose radiotherapy. Indications, dose, and radiobiological mechanisms involved

Low-dose radiotherapy (LD-RT) has been used for several benign diseases, including arthrodegenerative and inflammatory pathologies. Despite its effectiveness in clinical practice, little is known about the mechanisms through which LD-RT modulates the various phases of the inflammatory response and about the optimal dose fractionation. The objective of this review is to deepen knowledge about the most effective LD-RT treatment schedule and radiobiological mechanisms underlying the anti-inflammatory effects of LD-RT in various in vitro experiments, in vivo studies, and clinical studies.

[Effects of Pilose antler polypeptide on apoptosis of chondrocyte and related cytokines in experimental knee osteoarthritis]

OBJECTIVE

To explore the effects of Pilose antler polypeptide on apoptosis of chondrocyte and related cytokines in experimental knee osteoarthritis.

METHODS

Totally 64 New Zealand White rabbits of 6 months old were randomly divided into 2 groups:normal group(n=8)and model group (n=56). Model group was surgically induced into knee osteoarthritis model by method of Hulth. After successful modeling,the rabbits of model group were further divided into 2 groups: Pilose antler polypeptide-treatment group (n=24) and control group (n=24). Pilose antler polypeptide-treatment group received 0.5 ml intraarticular injection of Pilose antler polypeptide dilution liquid once per 2 days for 30 days while control group received 0.5 ml intra-articular injection of physiological saline. On days 7, 15 and 30 after intervention, articular cartilage samples and synovial fluid were collected respectively. The morphological changes of articular cartilage under optical microscope and the structural change of chondrocyte were observed by transmission electron microscopy. The levels of interleukin-1beta and tumor necrosis factor-alpha in synovial fluid was detected by Enzyme-linked Immunosorbent Assay.

RESULTS

Along with the extending of time, articular cartilage degenerated gradually and chondrocytes apoptosis increased significantly. On days 7,15 and 30 after intervention, the chondrocyte apoptosis index of the Pilose antler polypeptide-treatment group were (20.30 +/- 1.23), (28.60 +/- 2.37), (37.10 +/- 1.82) and those of control group were (31.50 +/- 2.44), (34.40 +/- 1.77), (42.30 +/- 2.33). There were significant differences between them (P<0.05). At the same time, the chondrocyte apoptosis index of the Pilose antler polypeptide-treatment group were lower than those of control group,which had a statistical significance (P<0.05). On days 7,15 and 30 after intervention, the levels of interleukin-1beta in synovia fluid of Pilose antler polypeptide-treatment group were (15.81 +/- 1.26), (12.59 +/- 1.42), (9.57 +/- 0.92) microg/L and the level of tumor necrosis factor-alpha were (48.47 +/- 2.64), (43.46 +/- 1.33), (40.96 +/- 1.05) microg/L, with statistical differences(P<0.05). The levels of interleukin-1beta in synovia fluid of control group were (18.92 +/- 1.83), (20.25 +/- 2.76), (22.13 +/- 2.24) microg/L and the levels of tumor necrosis factor-alpha were (57.92 +/- 2.12), (60.25 +/- 1.48), (63.35 +/- 2.15) microg/L. At the same period,the levels of interleukin-1beta and tumor necrosis factor-alpha were lower than those of the control group,which had a statistical significance (P<0.05).

CONCLUSION

Pilose antler polypeptide can inhibit chondrocytes apoptosis, decrease the levels of interleukin-1beta and tumor necrosis factor-alpha and delay the degeneration of articular cartilage to some extent.

[Experimental study on invigorating kidney and activating blood on preventing and curing SD rats with knee osteoarthritis]

OBJECTIVE

To explore the effects and mechanism of invigorating kidney and activating blood, invigorating kidney and expelling wind on hemorheology, IL-1β and TNF-α of SD rats with knee osteoarthritis, then definite the evolution of muscle certified turning into heumatism and compare the effect of Chinese herbal.

METHODS

One hundred and eighty SD rats with 3-month-old (each weight was 185 to 215 g) received intra-articular injection of papain solution for establishing knee OA models. All rats were randomly divided into activating blood group, preventing group, expelling wind group, invigorating kidney group, invigorating kidney and activating blood group and model group. Laboratory indexes were obtained at the 30th, 60th, 90th days after gastric perfusion, which including state of mind, activity, fur, weight, joint swelling, largely image, hemorheology, inflammation and HE pathological appearance.

RESULTS

After operation, rats appeared blood stasis and swelling and difficulty crawling. There was significant difference of hemorheology in invigorating kidney and activating blood group the content of IL-1β and TNF-α was obviously lower than model group (P < 0.05 ). While the content of IL-1β and TNF-α on the early stage was obviously higher than late stage (P < 0.05).

CONCLUSION

Knee osteoarthritis mainly show synovial inflammation at the early stage, inflammation at early stage is more severe than late; invigorating kidney and activating blood decoction can inhibit the knee cartilage injury, improve blood circulation and prevent local inflammatory reaction. Activating blood decoction and invigorating kidney and activating blood Decoction have certain curative effect in early time, but the effects of invigorating kidney and activating blood Decoction is more effective than other on the late stage.

[Randomized controlled clinical trials of red-hot filiform needle puncturing for knee ostarthritis and inflammatory cytokines in knee articular fluid in senile knee ostarthritis patients]

OBJECTIVE

To observe the effect of red-hot filiform needle puncturing on the pain severity of knee ostarthritis (OA) and the inflammatory cytokine levels in the knee articular cavity (KAC) fluid in senile knee OA patients so as to find a better therapy for knee OA.

METHODS

A total of 200 senile knee OA outpatients (who signed an informed consent) were randomized into treatment group and control group (n = 100/group) according to a random number table and their visiting sequence. Futu (LI 18), Neixiyan (EX-LE 4), Yanglingquan (GB 34), Yinlingquan (SP 9), Zusanli (ST 36), etc. on the affected side of the body were punctured with red-hot filiform needles (cauterized on an alcohol burner) or routine filiform needles, with the needles retained for 30 min. The treatment was conducted once every other day, 15 sessions altogether. Before and after the treatment, the patients' KAC fluid was sampled for assaying the contents of IL-1, IL-6 and tumor necrosis factor (TNF)-alpha with enzyme-linked immunosorbent assay (ELISA). The pain severity was tested by using visual analogue scale (VAS) and the comprehensive therapeutic effect was evaluated by using clinical symptoms and signs, functional activity and pain degrees.

RESULTS

In comparison with pre-treatment, IL-1, IL-6 and TNF-alpha contents in KAC fluid were decreased significantly in both treatment and control groups (P < 0.01). The IL-1, IL-6 and TNF-alpha levels were considerably lower in the treatment group than in the control group following the treatment (P < 0.01), suggesting a marked relief of inflammation in the affected knee joint. Compared to pre-treatment, the severity scores of illness state of both treatment and control groups were decreased remarkably (P < 0.01), and the VAS score of the treatment group was significantly lower than that of the control group after the treatment (P < 0.05). Of the two 100 knee OA outpatients in the treatment and control groups, 29 (29%) and 21 (21%) were controlled in their symptoms and signs; 46 (46%) and 34 (34%) experienced apparent improvement; 18 (18%) and 29 (29%) were effective; 7 (7%) and 16 (16%) failed in the treatment. The comprehensive therapeutic effect of the treatment group was significantly superior to that of the control group (P < 0.01).

CONCLUSION

Red-hot filiform needle puncturing is superior to routine filiform needle puncturing in relieving senile knee OA and in reducing inflammatory cytokine levels in knee OA patients.

Human knee synovial fluid cytokines correlated with grade of knee osteoarthritis--a pilot study

The purpose of this pilot study was to evaluate the cytokine profile of human knee synovial fluid and correlate this with the subject's degree of articular cartilage degradation, radiographic score, and synovial histology.

MATERIALS AND METHODS

Synovial fluid was withdrawn before knee meniscectomy in 12 subjects with varying degrees of osteoarthritis and assayed for 21 cytokines, using a multiplex cytokine assay and flow cytometry instrumentation. Articular cartilage surfaces were scored by a single orthopaedic surgeon on the basis of the International Cartilage Repair Society (ICRS) classification during the arthroscopy, and posterior-anterior knee radiographs were graded using the Kellgren-Lawrence (KL) classification. Synovial biopsies were taken in four zones at the time of surgery for histological analysis.

RESULTS

Significant concentration differences in IL-2, IL-5, MCP-1, and MIP-1 were found between subjects with advanced arthritis and subjects with little or no arthritis on the ICRS scale (p < .05). No such differences could be appreciated using KL scores. There was no correlation between histology samples and visualized surface osteoarthritis.

CONCLUSION

This data suggests a molecular basis of disease progression, with higher levels of cytokines indicative of greater degrees of osteoarthritis. These results add pilot data that can assist investigators in conducting a comparative observational study of the levels of inflammatory cytokines with radiologic and arthroscopic assessments of osteoarthritis.

[Study on correlation between the pathological changes under arthroscopy and the cytokine levels in the knee osteoarthritis of the Blood Stasis type]

OBJECTIVE

To explore the correlation between cytokine levels and the pathological changes under arthroscopy in knee osteoarthritis of Blood Stasis type.

METHODS

From 2009.2 to 2010.3, 90 patients with knee osteoarthritis were reviewed. Among the patients, 17 patients were male and 73 patients were female, ranging in age from 40 to 70 years, averaged 57.2 years, the duration of the disease ranged from 1 month to 10 years, with a mean of 3.4 years. Thirty-one patients had osteoarthritis in left knee, and 59 patients in right knee. The patients had the syndrome of blood stasis. All the patients had pain and morning stiffness; most patients had joint interlocking; and all the patients didn't have joint swelling. The synovial fluid was collected before surgery, and ELISA was used to detect the contents of interleukin-1beta and transforming growth factor-beta1. At the same time, the pathological changes of the joint were observed under the arthroscopy. Based on the above datum analysis, the severity of knee osteoarthritis of blood stasis type was studied, and the correlation between different types of pathological changes under arthroscopy and cytokine levels was analyzed.

RESULTS

The contents of IL-1beta and TGF-beta1 in synovial fluid were (28.18 +/- 5.57) pg/ml and (51.69 +/- 6.56) pg/ml respectively. The level of IL-1beta of grade III-IV cartilage degeneration was (30.65 +/- 3.48) pg/ml, which was significantly higher than (20.55 +/- 3.50) pg/ml of grade I-II cartilage degeneration group; the level of TGF-beta1 of grade I-II cartilage degeneration was (58.18 +/- 3.98) pg/ml,which was significantly higher than (49.59 +/- 5.83) pg/ml of grade II-IV cartilage degeneration group. IL-1beta and cartilage degeneration was positively correlated, the correlation coefficient was 0.744; TGF-beta1 and cartilage degeneration was negatively correlated, the correlation coefficient was -0.563. The level of IL-1beta of grade II-III synovial hyperplasia was (33.48 +/- 2.95) pg/ml, which was significantly higher than (25.40 +/- 4.50) pg/ml of grade I synovial hyperplasia group; IL-beta was positively correlated with synovial hyperplasia, the cor- relation coefficient was 0.801. The levels of IL-1beta of grade I osteophyte formation was (34.18 +/- 2.69) pg/ml, which was significantly higher than (25.74 +/- 4.48) pg/ml of grade 0 osteophyte formation group; the level of TGF-beta 1 of grade 0 osteophyte formation was (53.11 +/- 6.78) pg/ml, which was higher than (48.21 +/- 4.47) pg/ml of grade I osteophyte formation group. IL-1beta was positively correlated with osteophyte formation, the correlation coefficient was 0.762; TGF-beta1 was negatively correlated with osteophyte formation, the correlation coefficient was - 0.340.

CONCLUSION

All the patients with knee osteoarthritis identified as blood stasis syndrome have pathological changes such as articular cartilage degeneration and synovial hyperplasia. The level of IL-1beta has important reference value to estimate the severity of cartilage degeneration, synovial hyperplasia and osteophyte proliferation.

Pharmacoproteomic study of the effects of chondroitin and glucosamine sulfate on human articular chondrocytes

INTRODUCTION

Chondroitin sulfate (CS) and glucosamine sulfate (GS) are symptomatic slow-acting drugs for osteoarthritis (OA) widely used in clinic. Despite their widespread use, knowledge of the specific molecular mechanisms of their action is limited. The aim of this work is to explore the utility of a pharmacoproteomic approach for the identification of specific molecules involved in the pharmacological effect of GS and CS.

METHODS

Chondrocytes obtained from three healthy donors were treated with GS 10 mM and/or CS 200 μg/mL, and then stimulated with interleukin-1β (IL-1β) 10 ng/mL. Whole cell proteins were isolated 24 hours later and resolved by two-dimensional electrophoresis. The gels were stained with SYPRORuby. Modulated proteins were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF/TOF) mass spectrometry. Real-time PCR and Western blot analyses were performed to validate our results.

RESULTS

A total of 31 different proteins were altered by GS or/and CS treatment when compared to control. Regarding their predicted biological function, 35% of the proteins modulated by GS are involved in signal transduction pathways, 15% in redox and stress response, and 25% in protein synthesis and folding processes. Interestingly, CS affects mainly energy production (31%) and metabolic pathways (13%), decreasing the expression levels of ten proteins. The chaperone GRP78 was found to be remarkably increased by GS alone and in combination with CS, a fact that unveils a putative mechanism for the reported anti-inflammatory effect of GS in OA. On the other hand, the antioxidant enzyme superoxide dismutase 2 (SOD2) was significantly decreased by both drugs and synergistically by their combination, thus suggesting a drug-induced decrease of the oxidative stress caused by IL-1β in chondrocytes.

CONCLUSIONS

CS and GS differentially modulate the proteomic profile of human chondrocytes. This pharmacoproteomic approach unravels the complex intracellular mechanisms that are modulated by these drugs on IL1β-stimulated human articular chondrocytes.

Cytokine receptor-like factor 1 is highly expressed in damaged human knee osteoarthritic cartilage and involved in osteoarthritis downstream of TGF-beta

Osteoarthritis (OA) is the most prevalent joint disease and is characterized by pain and functional loss of the joint. However, the pathogenic mechanism of OA remains unclear, and no drug therapy for preventing its progress has been established. To identify genes related to the progress of OA, the gene expression profiles of paired intact and damaged cartilage obtained from OA patients undergoing joint substitution were compared using oligo microarrays. Using functional categorization combined with gene ontology and a statistical analysis, five genes were found to be highly expressed in damaged cartilage (HBEGF, ASUS, CRLF1, LOX, CDA), whereas three genes were highly expressed in intact tissues (CHST2, PTPRD, CPAN6). Among these genes, the upregulated expression of CRLF1 was reconfirmed using real-time PCR, and the in vivo expression of CRLF1 was detected in clusters of chondrocytes and fibrocartilage-like cells in damaged OA cartilages using in situ hybridization. In vitro, the transcriptional level of CRLF1 was positively regulated by TGF-beta1 in the mouse chondrogenic cell line ATDC5. Additionally, the CRLF1/CLC complex promoted the proliferation of ATDC5 cells and suppressed the expression level of aggrecan and type II collagen. Our data suggest that the CRLF1/CLC complex disrupts cartilage homeostasis and promotes the progress of OA by enhancing the proliferation of chondrocytes and suppressing the production of cartilage matrix. A component of the complex, CRLF1, may be useful as a biomarker of OA; and the corresponding receptor is a potential new drug target for OA.

A high interleukin 1 receptor antagonist/IL-1beta ratio occurs naturally in knee osteoarthritis

OBJECTIVE

To assess the interleukin 1 receptor antagonist (IL-1Ra)/IL-1beta ratio in synovial fluid (SF) of patients with knee osteoarthritis (OA) or rheumatoid arthritis (RA) to determine a possible relation between cytokine level and disease activity.

METHODS

IL-1beta and IL-1Ra concentrations were measured by ELISA in knee SF from patients with OA (n = 42) or RA (n = 11). For OA patients, pain and disability were assessed by a visual analog scale (VAS) and the Lequesne index. RA disease activity was assessed using the Disease Activity Score 28 Joint Count (DAS28).

RESULTS

Patients with OA showed lower median levels of IL-1beta and IL-1Ra in SF than patients with RA (p < 0.001) but a higher IL-1Ra/IL-1beta ratio: 1793 (584-6221) versus 773.5 (187.64-1570.5) (p = 0.05). For patients with OA, the IL-1Ra/IL-1beta ratio was not associated with pain or disability. For patients with RA, the IL-1Ra/IL-1beta ratio and IL-1Ra and IL-1beta levels were related to SF white blood cell count.

CONCLUSION

High endogenous IL-1Ra/IL-1beta ratio occurs in SF from knee OA and does not correlate with pain or Lequesne index. Our results suggest that intraarticular injection of IL-1Ra might be self-limited in patients with knee OA and a naturally high SF ratio.

Selective iNOS inhibitor 1400W enhances anti-catabolic IL-10 and reduces destructive MMP-10 in OA cartilage. Survey of the effects of 1400W on inflammatory mediators produced by OA cartilage as detected by protein antibody array

OBJECTIVES

In osteoarthritis (OA), the balance between catabolic and anabolic mediators and their regulators in cartilage is disturbed. Proinflammatory cytokine interleukin-1 (IL-1) plays a central role in cartilage destruction and nitric oxide (NO) mediates many of its destructive effects. In the present study, we investigated the secretion of 40 mediators related to inflammation or cartilage degradation by OA cartilage samples with a protein antibody array. The effects of IL-1 and a selective iNOS-inhibitor 1400W on the mediator release were also studied.

METHODS

Cartilage tissue was obtained from the leftover pieces of total knee replacement surgery from OA patients. Protein antibody array was used to measure production of 40 mediators in the culture medium. ELISA was used to confirm the antibody array results.

RESULTS

OA cartilage secreted spontaneously 15 out of the 40 measured mediators. IL-1Beta enhanced production of 11 of these inflammatory mediators in OA cartilage along with increased NO production. Treatment with a selective iNOS inhibitor 1400W enhanced the production of IL-10, while the levels of MMP-10 were reduced in IL-1 -treated OA cartilage.

CONCLUSION

OA cartilage produces many of the mediators involved in the pathogenesis of OA. The ability of 1400W to enhance levels of anti-catabolic IL-10 and to reduce levels of destructive MMP-10 points to the anti-inflammatory mechanisms that iNOS-inhibitors may have.

The lack of correlation between the increased frequency of allele IL-1RN*2 of interleukin-1 receptor antagonist gene in Czech patients with knee osteoarthritis and the markers of cartilage degradation

Primary OA is a common multifactorial disease with not fully clarified molecular factors influencing the development of the disease. Among factors disturbing the cartilage integrity are cytokines, such as IL-1, which can stimulate proteinases, resulting in the cartilage destruction. In this regard, IL-1RA competing with IL-1 for binding to its receptor may act as an inhibitor of cartilage breakdown. Because of the possible functional implications, we tested VNTR polymorphism in the second intron of the IL-1RN gene as a putative factor of susceptibility to knee OA. Fifty patients with primary knee OA (diagnosed according to ACR criteria) and 170 healthy controls were included into the study. PCR using primers flanking the VNTR region containing variable numbers of an 86-bp tandem repeat was employed to test the hypothesis. An increased frequency and carriage rate of the IL-1RN*2 allele was found in OA patients in comparison with controls (28 % vs. 15 %, P = 0.0013, OR = 2.97; 95% CI 1.55-5.68 for frequency; 52.5 % vs. 25.3 %, P = 0.0019, OR = 2.95; 95% CI 1.54-5.68 for carriage rate). In addition, a higher frequency of genotype IL-1RN*1/*2 in OA patients was observed as compared with controls (42 % vs. 20.6 %, P = 0.0032, OR = 2.79; 95% CI 1.42-5.48). These results suggest that the IL-1RN*2 allele might represent a factor of susceptibility to OA; however, no correlation between this allele and the markers of cartilage degradation was found.

Activating and inhibitory receptors on synovial fluid natural killer cells of arthritis patients: role of CD94/NKG2A in control of cytokine secretion

Natural killer (NK) cells are activated early during inflammatory events and contribute to the shaping of the ensuing adaptive immune response. To further understand the role for NK cells in inflammation, we investigated the phenotype and function of synovial fluid (SF) NK cells from patients with chronic joint inflammation, as well as from patients with transient inflammation of the knee following trauma. We confirm that synovial NK cells are similar to the well-characterized CD56(bright) peripheral blood (PB) NK-cell subset present in healthy individuals. However, compared to this PB subset the synovial NK cells express a higher degree of activation markers including CD69 and NKp44, the latter being up-regulated also on CD56(bright) NK cells in the PB of patients. Activated synovial NK cells produced interferon-gamma and tumour necrosis factor, and the production was further up-regulated by antibody masking of CD94/NKG2A, and down-regulated by target cells expressing human leucocyte antigen-E in complex with peptides known to engage CD94/NKG2A. We conclude that synovial NK cells have an activated phenotype and that CD94/NKG2A is a key regulator of synovial NK-cell cytokine synthesis.

Dual impact of chronic liver disease and amaebiasis on immunopathogenesis of primary osteoarthritis in Egyptians

Sixty cases with primary knee OA were equally categorized into six groups with EHI (Gs 1, 2, 3) or without (Gs 4, 5, 6). GI included cases with HCV, GII cases with RHS & HCV and GIII cases with a history of non-active schistosomiasis whereas Gs 4, 5 & 6 included cases without EHI. Clinical examination with inclusion criteria of pathological manifestations w\as associated with biochemical evaluation of adhesion molecules (E-selectin, P-selectin, intracellular adhesion molecule-3 "ICAM-3") in plasma and synovial fluid. Synovial fluid indices (IgG, IgA, IgM, & C3) were evaluated as well as indices of inflammation and oxidative stress (Beta 2 microglobulin, Haptaglobulin, fibronectin, total thiol, superoxide dismutase, thiobarbituric acid reactive substance & hyaluronan) in synovial fluid and indices activating fibrogenesis in serum and plasma (procollagen III, plasma prolidase, Interleukin-1 beta, Interleukin-6 & TNF alpha). The results showed a positive relationship between indices activating vascular damage, fibrogenesis and immuno-inflammatory response with higher change magnitude in EHI cases particularly with combined HCV & RHS. This implement the dual role of hepatic insult and intestinal amoebiasis on immune mediated mechanisms activating inflammatory response in OA cases reflecting common signaling pathways associated with pathogenesis of multifaceted origin.

Elevated IL-6 levels in the synovial fluid of osteoarthritis patients stem from plasma cells

OBJECTIVE

To analyse the levels of interleukin-6 (IL-6) in the synovial fluids and sera of patients with osteoarthritis (OA) and to identify the IL-6-secreting cells.

METHODS

Serum, synovial fluid, synovial tissue, and articular cartilage samples were collected from 49 OA patients with end-stage knee or hip OA who underwent joint replacement surgery. Serum and synovial fluid levels of IL-6 were measured by enzyme-linked immunosorbent assay (ELISA) and IL-6-secreting cells were identified by immunohistochemistry.

RESULTS

Eight out of 49 patients (16%) exhibited elevated IL-6 levels in the synovial fluids, averaging at 2022+/-526 pg/mL, while the levels in the rest of the patients averaged at 132+/-19 pg/mL. The sera levels of all patients were comparable in the 10 pg/mL range. Immunohistochemical analyses revealed plasma cells in the synovial lining of the high producers as the source of IL-6.

CONCLUSIONS

Synovial fluid IL-6 levels may help to classify OA patients and may point to a subgroup with a particular impact from their immune system.

Synovial fluid and peripheral blood immune complexes of patients with rheumatoid arthritis induce apoptosis in cytokine-activated chondrocytes

The destruction of cartilage is an important characteristic of rheumatoid arthritis (RA). Immune complexes (IC) are usually found in high amounts in RA synovial fluids (SF) and in the superficial layers of RA cartilage. The objective of this study was to investigate if IC have a direct influence on proliferation, survival and production of nitric oxide (NO) of cytokine-activated chondrocytes. Primary bovine chondrocytes were incubated with cytokines (huIL-1alpha, bovIFN-gamma, huTNF-alpha) and IC containing precipitates of peripheral blood (PB) and/or synovial fluid (SF) of 14 RA patients, 5 osteoarthritis (OA) patients and 10 healthy age and sex-matched controls. After 48 h, chondrocyte viability, proliferation, apoptosis, NO production and oxygen radical levels were measured. Staining with May-Grünwald-Giemsa after incubation with IC of RA PB and SF, showed apoptotic chondrocytes with condensation of the nuclei. The proliferation rates of cytokine-activated chondrocytes, incubated with sera and SF IC of RA patients were significantly decreased compared to chondrocytes, incubated with sera and SF IC of OA patients and compared to sera of controls. Quantitative evaluation of apoptotic cells by annexin-V/propidium iodide and TUNEL assays revealed a significant increase after incubation with sera and SF IC of RA patients, compared to control sera and OAs sera and SF. In all TUNEL positive samples, active-caspase-3-positive cells were found. There was a significant increase of chondrocyte NO production, after incubation with SF IC of RA patients, compared to OA SF. These results support the hypothesis that IC, present in serum and SF of RA patients, have a profound influence on chondrocyte growth, NO production and apoptosis, contributing to cartilage destruction in RA.

[Effects of electroacupuncture on synovia IL-1beta and TNF-alpha contents in the rabbit with knee osteoarthritis]

OBJECTIVE

To observe the effect of electroacupuncture (EA) on synovia IL-1beta and TNF-alpha contents in rabbits with knee osteoarthritis (KOA).

METHODS

A total of 40 New Zealand rabbits were randomly divided into control, model, massage and EA groups. KOA model was established by gypsum fixing method. EA (2 Hz, 1-3 mA) was applied to left "Xiyan" (EX-LE 5), "Yanglingquan" (GB 34), "Xuehai" (SP 10), "Zusanli" (ST 36) and "Liangqiu" (ST 34) for 30 min, once daily and continuously for 21 days. For massage group, the affected knee joint was pressed, kneaded, stretched and rotated repeatedly for 15 min every time, followed by forced running about 100 m. The intra-joint synovia was collected (0.4-0.6 mL) for detecting the contents of IL-1beta and TNF-alpha with radioimmunoassay.

RESULTS

No IL-1beta and TNF-alpha were detected in the synovia in control group, while in the other 3 groups, synovia IL-1beta and TNF-alpha levels increased significantly. Before treatment, no significant differences were found among model, EA and massage groups in the levels of IL-1beta and TNF-alpha (P > 0.05), while after the treatment the two indexes both decreased considerably (P < 0.05). Compared with model group, the two indexes were remarkably lower (P < 0.05), but no significant differences were found between EA and massage groups in synovia IL-1beta and TNF-alpha contents (P > 0.05).

CONCLUSION

Both EA and massage can effectively suppress the release of synovia IL-1beta and TNF-alpha in KOA of rabbits, which may contribute to the effect of acupuncture in the treatment of osteoarthritis.

B Cell Clonal Expansion and Somatic Hypermutation of Ig Variable Heavy Chain Genes in the Synovial Membrane of Patients with Osteoarthritis

Inflammatory mediators have been explored as possible factors in the initiation and/or progression of osteoarthritis (OA). This study shows that synovial infiltration by B lymphocytes is present in almost half of the knee OA cases. The degree of B lymphocyte infiltration is associated with more pronounced synovial inflammation and with the presence of plasma cells and lymphoid follicles in more severe cases. To examine whether these B cells are merely bystanders or could be involved in the pathogenesis of OA, we analyzed the Ig H chain variable region (V(H)) genes of B cells recovered from the synovial membrane of five OA patients with marked B cell infiltration. Sequence analysis of CDR3 regions of rearranged VDJ genes revealed clonal or oligoclonal B cell expansions in all cases. Expanded B cell clones in four of five OA patients showed clustered somatic mutations, occurring mainly in the CDRs and with a high replacement-to-silent ratio (>2.9), indicating that these cells are postgerminal center B cells that had been positively selected through their Ag receptor. These data demonstrate the presence in inflamed knee OA synovium of clonally expanded, Ag-driven B cells that may contribute to the development or progression of the disease.

High molecular weight hyaluronic acid down-regulates the gene expression of osteoarthritis-associated cytokines and enzymes in fibroblast-like synoviocytes from patients with early osteoarthritis

OBJECTIVE

Activated synoviocytes play important roles in the progression of human osteoarthritis (OA). Intra-articular injection of high molecular weight hyaluronic acid (HMW-HA) has been used as viscosupplementation for knee OA but its effect on synoviocytes remains undisclosed. This study aims to investigate the effects of HMW-HA on the gene expression of 16 OA-associated cytokines and enzymes, including interleukin (IL)-1beta, IL-6, IL-8, leukemia inhibitory factor (LIF), tumor necrosis factor (TNF)-alpha, TNF-alpha converting enzyme (TACE), matrix metalloproteinase (MMP)-1, MMP-2, MMP-3, MMP-9, MMP-13, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, aggrecanase-1, aggrecanase-2, and inducible nitric oxide synthase (iNOS), in fibroblast-like synoviocytes (FLS) from patients with early stage OA.

METHOD

Synovial fluid-derived FLS were obtained from the knees of 15 patients with early stage OA. IL-1-stimulated or unstimulated FLS were cultured with or without the treatment of 600-800kDa HMW-HA. Moreover, blocking experiments with anti-CD44 monoclonal antibodies (mAb) were used to examine the involvement of CD44 in HMW-HA effects. We designed and validated the real-time quantitative polymerase chain reaction (Q-PCR) assays with SYBR Green dyes for simultaneous quantification of the expression of the 16 genes.

RESULTS

HMW-HA down-regulated IL-8 and iNOS gene expression in unstimulated FLS and down-regulated aggrecanase-2 and TNF-alpha gene expression in IL-1-stimulated FLS. CD44 blocking inhibited the down-regulatory effects of HMW-HA on gene expression.

CONCLUSION

HMW-HA may have a structure-modifying effect for OA by down-regulation of aggrecanase-2 in FLS. HMW-HA also has an anti-inflammatory effect by down-regulation of TNF-alpha, IL-8, and iNOS in FLS. These effects may be mediated through the interaction of CD44 and HMW-HA.

[The influence of laser irradiation of low-power density on an experimental cartilage damage in rabbit knee-joints: an in vivo investigation considering macroscopic, histological and immunohistochemical changes]

In a total of 45 rabbits, knee-joint arthrosis was induced according to the Hulth & Telhag model. Depending on the post-operative survival time, the cartilage was investigated macroscopically, histologically and immunohistochemically (within a period of 10 days to 8 months). Thereafter, the influence of laser irradiation at a wavelength of 692.6 nm and energy densities of 1 and 4 J/cm2 on the cartilage morphology seven days following the exposure was examined. After joint instability surgery it was found out that the cartilage changes in the main stress area (MSA) and in regions outside the main stress area (ROMSA) progressed differently. Various qualitative and semi-quantitative changes were found for collagens I, II, IV and V, and for the glycoproteins fibronectin and tenascin. Immunohistochemically, there was a growing expression of collagen I in the apical layers, collagen II showed a stronger pericellular expression, and collagen IV showed, after an initial growth of the pericellular expression, a reduced territorial expression and a stronger apical-interterritorial expression in the osteoarthrotic cartilage. For fibronectin, the cellular expression turned out to grow in the ROMSA. In the MSA it decreased, but at the same time the interterritorial expression grew. For Tanascin, there was a decrease of the interterritorial expression in the radial zone while the pericellular and interterritorial expression of the apical layers of the osteoarthrotic cartilage grew. Lasing proved to significantly influence the osteoarthrotically changed cartilage when applied at an energy density of 1 J/cm2, i.e., the morphological changes had not yet progressed to the extent the control group had. Both the chondrocyte density and the glucosaminoglycan content turned out to be higher. When lasing was applied at higher energy densities, no significant difference among the control groups was found. Thus, it could be demonstrated in vivo that an arthrotic process decelerates through the influence of laser light of low-energy densities.

Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation

OBJECTIVE

Both matrix metalloprotease (MMP) activity and cathepsin K (CK) activity have been implicated in cartilage turnover. We investigated the relative contribution of MMP activity and CK activity in cartilage degradation using ex vivo and in vivo models.

METHODS

Bovine articular cartilage 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 (GAG), hydroxyproline, and cross-linked C-telopeptide fragments of type II collagen (CTX-II), which were compared to immunohistochemical evaluations of proteoglycans and CTX-II. We assessed MMP expression by gelatine zymography and CK expression by immunohistochemistry. In vivo, CTX-II release was measured from CK-deficient mice.

RESULTS

OSM and TNF-alpha combined induced significant (P<0.01) increase in cartilage degradation products measured by hydroxyproline and CTX-II compared to vehicle control. The cytokines potently induced MMP expression, assessed by zymography, and CK expression investigated by immunohistochemistry. Inhibition of MMP activity completely abrogated hydroxyproline and CTX-II release (P<0.01) and GAG release (P<0.05). In contrast, E64 resulted in increased CTX-II release by 100% (P<0.05) and inhibited GAG release by 30%. Up-regulation of CTX-II fragments was confirmed in 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 collagen metabolism.

Expressionsanalyse verschiedener Kollagene und Zytokine in Knorpelzellen aus arthrotisch veränderten Hüft- und Kniegelenken

AIM

Osteoarthritis (OA) is characterized by an irreversible destruction of articular cartilage. This is associated with a multiplicity of factors, causing an increased catabolic metabolism in cartilage. However, the prevalence of the OA is very variable in different joints. Therefore , we conducted a comparative analysis of chondrocytes derived from knee and hip joints with respect to their expression of inflammatory factors, such as IL-1beta, IL-1beta-receptorantagonist, iNOS, components of cartilage matrix (collagen I, II, and VI) as well as vimentin.

METHODS

Different cytokines and proteins were detected by immune-histochemical staining of cartilage samples ex vivo. Further, chondrocytes were isolated from OA knee and hip joints, expanded in vitro and gene expression patterns were investigated by quantitative RT-PCR.

RESULTS

Chondrocytes from knee and hip joints of OA patients express collagenes I, II and VI, IL-1beta and IL-1beta-RA, iNOS as well as Vimentin. A significant difference in gene expression patterns was not found in chondrocytes from the hip joints versus the knee joint ex vivo or in primary culture cells in vitro. However, in vitro the expression of type I collagen exceeded the expression of type II collagen. The IL-1beta-expression was high ex vivo, remained low during primary culture but was significantly elevated after primary culture in hip chondrocytes.

CONCLUSION

Osteoarthritic gene expression patterns in cells derived from hip or knee joints ex vivo and in primary culture were not significantly different. We conclude that the rather frequent occurrence of OA in these joints in comparison to the ankle joint may be associated with a close physiological relation of cells in these joints. However, future studies which will include ankle cartilage must be investigated in further detail.

Synovial fluid levels of anti-cyclic citrullinated peptide antibodies and IgA rheumatoid factor in rheumatoid arthritis, psoriatic arthritis, and osteoarthritis

OBJECTIVE

To assess the levels of anti-cyclic citrullinated peptide (anti-CCP) and IgA rheumatoid factor (IgA-RF) in synovial fluids of patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and osteoarthritis (OA).

METHODS

Knee effusions of 29 patients with RA (23 women, 6 men; mean +/- SD age 60 +/- 15 years), 20 with PsA (6 women, 14 men; mean age 51 +/- 12 years), and 19 with OA (9 women, 10 men; mean age 73 +/- 11.8 years) were aspirated, tested for white blood cell (WBC) counts, centrifuged, and stored at -20 degrees . Sera of 22, 11, and 12 of these patients with RA, PsA, and OA, respectively, were similarly stored. IgG anti-CCP and IgA-RF were detected by enzyme-linked immunosorbent assay. Erythrocyte sedimentation rate and C-reactive protein levels were used as measures of disease activity.

RESULTS

Mean levels of synovial fluid anti-CCP and IgA-RF were significantly increased in RA joint effusions compared with PsA and OA (anti-CCP: 150 +/- 134, 34 +/- 29, and 24 +/- 26 units, respectively [P < 0.003]; IgA-RF: 76 +/- 77, 15.7 +/- 10, and 18 +/- 20 units, respectively). No significant difference was noted between OA and PsA. A significant correlation was found between synovial fluid anti-CCP and serum anti-CCP and IgA-RF. In patients with RA, a significant correlation was found between synovial fluid WBC counts and IgA-RF (P = 0.03) and serum IgA-RF (P = 0.008), but not between synovial fluid and serum anti-CCP levels. In RA patients, C-reactive protein correlated with serum IgA-RF.

CONCLUSION

Anti-CCP and IgA-RF were significantly increased in synovial fluid of RA in comparison with PsA and OA patients.

Ultrasmall supraparamagnetic iron oxide-enhanced magnetic resonance imaging of antigen-induced arthritis: a comparative study between SHU 555 C, ferumoxtran-10, and ferumoxytol

OBJECTIVES

We sought to compare the ability of 3 ultrasmall superparamagnetic iron oxides (USPIOs) to detect and characterize antigen-induced arthritis with MR imaging.

MATERIALS AND METHODS

A monoarthritis was induced in the right knee of 18 rats. The left knee served as a normal control. Knees underwent magnetic resonance (MR) imaging before, up to 2 hours, and 24 hours after injection (p.i.) of 200 mumol Fe/kg SHU 555 C (n= 6), ferumoxtran-10 (n = 6), or ferumoxytol (n = 6), using T2-2D-SE 100/20,40,60,80/90 (TR/TE/flipangle), T2*-3D-spoiled gradient recalled (SPGR) 100/15/38, and T1-3D-SPGR 50/1,7/60 sequences.

RESULTS

Quantitative signal to noise ratio and DeltaSI data of arthritic knees on T1- and T2*-weighted MR images showed no significant differences between the 3 USPIOs (P > 0.05). At 2 hours p.i., SNR and DeltaSI data were significantly increased from baseline on T1-weighted images and significantly decreased on T2*-weighted images (P < 0.001). At 24 hours p.i., the T1-enhancement returned to baseline, whereas the T2*-enhancement remained significantly elevated (P < 0.001). Immunostains demonstrated an USPIO compartmentalization in macrophages in the arthritic synovium.

CONCLUSIONS

Based on the relatively small number of animals in our study group, inflammation in antigen-induced arthritis can be equally detected and characterized with any of the three USPIOs evaluated.

Synovial fluid macrophages are capable of osteoclast formation and resorption

To determine whether synovial fluid (SF) macrophages isolated from the SF of osteoarthritis (OA), rheumatoid arthritis (RA) and pyrophosphate arthropathy (PPA) joints are capable of osteoclast formation, and to investigate the cellular and humoral factors required for this to occur, SF macrophages (CD14+) were isolated from the knee joint SF from patients with OA, RA and PPA and cultured for up to 14 days with macrophage-colony stimulating factor (M-CSF) and soluble receptor activator for nuclear factor-kappaB ligand (RANKL) or tumour-necrosis factor-alpha (TNFalpha) and interleukin-1alpha (IL-1alpha). Osteoclast differentiation was assessed by expression of tartrate-resistant acid phosphatase (TRAP) and vitronectin receptor (VNR), F-actin ring formation and lacunar resorption. Osteoclast formation and lacunar resorption was seen in RANKL-treated cultures of SF macrophages isolated from OA, RA and PPA joints with the largest amount of resorption noted in RA and PPA SF macrophage cultures. In TNFalpha/IL-1alpha-treated RA and PPA SF macrophage cultures, osteoclasts capable of lacunar resorption were also formed. Lacunar resorption was more extensive in RANKL than TNFalpha/IL-1alpha-treated cultures. These findings indicate that SF macrophages are capable of differentiating into mature osteoclasts capable of lacunar resorption. M-CSF in combination with RANKL or TNFalpha/IL-1alpha was required for osteoclast formation. As inflammatory synovial fluids contain an increase in the number of macrophages and an increase in the amounts of RANKL, TNFalpha and IL-1alpha, these findings suggest that one means whereby bone erosions may form in rheumatoid or crystal arthritis is by differentiation of synovial fluid macrophages into osteoclasts.

VIP down-regulates TLR4 expression and TLR4-mediated chemokine production in human rheumatoid synovial fibroblasts

OBJECTIVES

Vasoactive intestinal peptide (VIP) has demonstrated therapeutic effects in arthritis by inhibiting both innate and acquired immune responses. We investigated the potential effects of VIP in the regulation of Toll-like receptor (TLR) expression and function in synovial fibroblasts from patients with rheumatoid arthritis (RA) and osteoarthritis (OA).

METHODS

Cultured fibroblast-like synoviocytes (FLS) were obtained from patients with RA and OA. The effects of VIP on basal or TNF-alpha or lipopolysaccharide (LPS)-induced TLR2, TLR4 and MyD88 expression and its effects on TLR4-mediated CCL2 and CXCL8 chemokine production were studied by reverse transcription-polymerase chain reaction, western blotting and enzyme-linked immunosorbent assay.

RESULTS

TLR2, TLR4 and MyD88 mRNA expression was increased in RA FLS compared with OA FLS. The largest increase was observed for TLR4 and there was also overexpression at the protein level in RA FLS. TLR4 and MyD88 mRNA and proteins were induced by LPS and TNF-alpha in RA FLS. VIP down-regulated the induced but not the constitutive expression of TLR4 and MyD88 in RA FLS. VIP treatment decreased CCL2 and CXCL8 chemokine production in response to TLR4 activation with LPS in RA FLS.

CONCLUSIONS

We demonstrate that VIP down-regulates LPS and TNF-alpha activation of TLR4 expression and the TLR4 functional response in terms of proinflammatory chemokine production. These studies suggest that the pleiotropic anti-inflammatory actions of VIP involve inhibitory effects on TLR4 expression and signalling.