A Preliminary Study of Combined Detection of COMP, TIMP-1, and MMP-3 in Synovial Fluid: Potential Indicators of Osteoarthritis Progression

Investigating the Anti-Inflammatory, Analgesic, and Chondroprotective Effects of Gynostemma pentaphyllum (Thunb.) Makino in Osteoarthritis: An In Vitro and In Vivo Study

Osteoarthritis (OA) is an age-related disease characterized by inflammation, pain, articular cartilage damage, synovitis, and irreversible disability. Gynostemma pentaphyllum (Thunb.) Makino (GP), a herbal medicine traditionally used in East Asia for its anti-inflammatory properties, was investigated for its potential to modulate OA pathology and symptoms. This study evaluated GP's efficacy in inhibiting pain, functional decline, and cartilage destruction in monosodium iodoacetate-induced OA and acetic acid-induced writhing models. Additionally, the effects of GP on OA-related inflammatory targets were assessed via mRNA and protein expression in rat knee cartilage and lipopolysaccharide-induced RAW 264.7 cells. The GP group demonstrated significant pain relief, functional improvement, and cartilage protection. Notably, GP inhibited key inflammatory mediators, including interleukin (IL)-1β, IL-6, matrix metalloproteinases (MMP)-3 and MMP-13, cyclooxygenase-2, and prostaglandin E receptor 2, surpassing the effects of active controls. These findings suggest that GP is a promising candidate for disease-modifying OA drugs and warrants further comprehensive studies.

Validation of a rapid collagenase activity detection technique based on fluorescent quenched gelatin with synovial fluid samples

BACKGROUND

Measuring collagenase activity is crucial in the field of joint health and disease management. Collagenases, enzymes responsible for collagen degradation, play a vital role in maintaining the balance between collagen synthesis and breakdown in joints. Dysregulation of collagenase activity leads to joint tissue degradation and diseases such as rheumatoid arthritis and osteoarthritis. The development of methods to measure collagenase activity is essential for diagnosis, disease severity assessment, treatment monitoring, and identification of therapeutic targets.

RESULTS

This study aimed to validate a rapid collagenase activity detection technique using synovial fluid samples. Antibody microarray analysis was initially performed to quantify the levels of matrix metalloproteinase-9 (MMP-9), a major collagenase in joints. Subsequently, the developed gelatin-based test utilizing fluorescence measurement was used to determine collagenase activity. There was a significant correlation between the presence of MMP-9 and collagenase activity. In addition, Lower Limit of Detection and Upper Limit of Detection can be preliminary estimated as 8 ng/mL and 48 ng/mL respectively.

CONCLUSIONS

The developed technique offers a potential point-of-care assessment of collagenase activity, providing real-time information for clinicians and researchers. By accurately quantifying collagenase activity, healthcare professionals can optimize patient care, improve treatment outcomes, and contribute to the understanding and management of joint-related disorders. Further research and validation are necessary to establish the full potential of this rapid collagenase activity detection method in clinical practice.

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

OBJECTIVES

Prior studies have demonstrated elevated inflammatory cytokine concentrations in the synovial fluid of articular fracture patients postinjury. Similarly, CT-based fracture energy measurements have been correlated with posttraumatic osteoarthritis risk after pilon fracture. The purpose of this study was to determine the associations between synovial fluid cytokine levels, fracture energy, and overall trauma to the body in articular fracture patients.

METHODS

Acute tibial plateau, tibial plafond, and rotational ankle fracture patients were prospectively enrolled from December 2011 through January 1, 2019. Synovial fluid concentrations of interleukin-1 beta, interleukin-1 receptor antagonist, IL-6, IL-8, IL-10, matrix metallopeptidase-1, MMP-3, and MMP-13 were quantified. Patient CT scans were used to calculate fracture energy. The Injury Severity Score (ISS) was used to relate cytokine levels to whole-body injury severity. Spearman rho correlation coefficients were calculated to assess the relationship between injury severity metrics and synovial fluid cytokine, chemokine, and matrix metallopeptidase concentrations.

RESULTS

Eighty-seven patients were enrolled with 42 had a tibial plateau fractures (OTA/AO 41B1-2, 41B2-14, 41B3-3, 41C1-3, 41C2-4, 41C3-16), 24 patients had a tibial plafond fracture (OTA/AO 43B1-2, 43B2-4, 43B3-5, 43C1-2, 43C2-3, 43C3-8), and 21 had a rotational ankle fracture (OTA/AO 44B1-3, 44B2-3, 44B3-6, 44C1-4, 44C2-5). Fracture energy significantly differed between fracture patterns, with ankle fractures involving substantially less fracture energy (median = 2.92 J) than plafond (10.85 J, P < 0.001) and plateau fractures (13.05 J, P < 0.001). After adjustment for multiple comparisons, MMP-3 was significantly correlated with transformed fracture energy (r = 0.41, 95% confidence interval [CI], 0.22-0.58, P < 0.001), while IL-1β was significantly correlated with the Injury Severity Score (Spearman ρ = 0.31, 95% CI, 0.08-0.49, P = 0.004).

CONCLUSIONS

Synovial fluid MMP-3 concentration was significantly correlated with CT-quantified fracture energy in intra-articular fracture patients. Given that in clinical practice fracture energy tends to correlate with posttraumatic osteoarthritis risk, MMP-3 may warrant further investigation for its role in posttraumatic osteoarthritis development after articular fracture.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Impact of diabetes mellitus on osteoarthritis: a scoping review on biomarkers

Osteoarthritis (OA) commonly affects the knee and hip joints and accounts for 19.3% of disability-adjusted life years and years lived with disability worldwide (Refs , ). Early management is important in order to avoid disability uphold quality of life (Ref. ). However, a lack of awareness of subclinical and early symptomatic stages of OA often hampers early management (Ref. ). Moreover, late diagnosis of OA among those with severe disease, at a stage when OA management becomes more complicated is common (Refs , , , ). Established risk factors for the development and progression of OA include increasing age, female, history of trauma and obesity (Ref. ). Recent studies have also drawn a link between OA and metabolic syndrome, which is characterized by insulin resistance, dyslipidaemia and hypertension (Refs , ).

Knee Osteotomy Decreases Joint Inflammation Based on Synovial Histology and Synovial Fluid Analysis

PURPOSE

To examine the biological changes in the joints of patients with knee osteoarthritis (OA) before and after around-knee osteotomy (AKO), focusing on synovial fluid (SF) and synovial pathological changes.

METHODS

Patients who underwent AKO for medial compartment knee OA between 2019 and 2021 were examined. SF and synovium were obtained at the time of AKO and plate removal after bone union (mean, 16.8 months [range: 11-38 months] postoperatively). SF volume and interleukin (IL)-6 concentrations in SF were assayed using enzyme-linked immunosorbent assay. Synovitis was assessed histologically using a semiquantitative scoring system. Macrophage infiltration was assessed by immunohistochemistry using a semiquantitative score for F4/80 expression. The M1/M2 ratio was calculated using percentage of cells positive for CD80 and CD163. The expression of proinflammatory cytokines was assessed by the percentage of IL-1β- and IL-6-positive cells. The number of vascular endothelial growth factor-positive luminal structures was counted to assess angiogenesis. The change in each parameter was compared before and after AKO using the Wilcoxon matched-pairs signed-rank test.

RESULTS

Twenty-four knees of 21 patients were included. SF volume and IL-6 concentration significantly decreased postoperatively (12.6 ± 2.1 mL vs 4.2 ± 0.6 mL; P < .0001 and 50.5 ± 8.6 pg/mL vs 20.7 ± 3.8 pg/mL; P = .0001, respectively). A significant reduction in synovitis score (P = .0001), macrophage infiltration (P < .0003), M1/M2 ratio (P < .0007), angiogenesis (P < .0001), and the percentage of IL-1β- and IL-6-positive cells in the intima (P < .008 and P < .002, respectively) was found after AKO.

CONCLUSIONS

SF volume and IL-6 concentrations in the SF decreased and inflammatory synovium pathology improved after AKO. In addition to biomechanical changes, the biological environment of the joint can be improved after AKO.

LEVEL OF EVIDENCE

Level IV, retrospective therapeutic case series.

Research Progress in Single-herb Chinese Medicine and Compound Medicine for Knee Osteoarthritis

Due to an increase in the aging population, osteoarthritis (OA), especially knee osteoarthritis (KOA), has increasingly become one of the diseases affecting the quality of life of the elderly. As the pathogenesis of KOA is still unclear, Western medicine treatment lacks specificity, and surgical treatment is difficult to cover all patients. Therefore, in recent years, traditional Chinese medicine (TCM) for the conservative treatment of KOA has received increasing attention. The advantages of TCM are clear, such as relief of symptoms, fewer adverse reactions, and wider applicability to patients. This paper mainly discusses the research progress in single-herb TCM and TCM compounds for KOA, aiming to demonstrate the effectiveness of TCM in the treatment of KOA. It also provides ideas for future research on the treatment of KOA by TCM and the pathogenesis of knee osteoarthritis.

Classification of distinct osteoarthritis subtypes with different knee joint tissues by gene expression profiles

Aims

Knee osteoarthritis (OA) involves a variety of tissues in the joint. Gene expression profiles in different tissues are of great importance in order to understand OA.

Methods

First, we obtained gene expression profiles of cartilage, synovium, subchondral bone, and meniscus from the Gene Expression Omnibus (GEO). Several datasets were standardized by merging and removing batch effects. Then, we used unsupervised clustering to divide OA into three subtypes. The gene ontology and pathway enrichment of three subtypes were analyzed. CIBERSORT was used to evaluate the infiltration of immune cells in different subtypes. Finally, OA-related genes were obtained from the Molecular Signatures Database for validation, and diagnostic markers were screened according to clinical characteristics. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to verify the effectiveness of markers.

Results

C1 subtype is mainly concentrated in the development of skeletal muscle organs, C2 lies in metabolic process and immune response, and C3 in pyroptosis and cell death process. Therefore, we divided OA into three subtypes: bone remodelling subtype (C1), immune metabolism subtype (C2), and cartilage degradation subtype (C3). The number of macrophage M0 and activated mast cells of C2 subtype was significantly higher than those of the other two subtypes. COL2A1 has significant differences in different subtypes. The expression of COL2A1 is related to age, and trafficking protein particle complex subunit 2 is related to the sex of OA patients.

Conclusion

This study linked different tissues with gene expression profiles, revealing different molecular subtypes of patients with knee OA. The relationship between clinical characteristics and OA-related genes was also studied, which provides a new concept for the diagnosis and treatment of OA.

sCTX II is a better biomarker than sMMP-3 to identify early knee osteoarthritis

The aim of this study is to assess the ability of serum MMP-3 and serum CTX-II levels to differentiate between normal and early knee osteoarthritis case (eKOA). Subjects with clinical features of primary knee osteoarthritis of K-L Grade I and K-L Grade II with ages more than 45 years were included in the case group (98), and healthy adults with ages less than 40 years were included in the control group (80). Those having knee pain for the last 3 months but having no radiological features were labeled as K-L grade I and those having minimal osteophytes on radiographs were labeled as K-L Grade II. Antero-posterior views of knee and serum levels of MMP-3 and CTX II were estimated. Cases show significantly higher values of both biomarkers than in controls (p < 0.0001). Both biomarkers show significantly higher values with an increase in K-L Grades, that is, K-L Grade 0 versus I (MMP-3: p = 0.003; CTX-II: p = 0.002), K-L Grade I versus II (MMP-3: p < 0.000; CTX-II: p < 0.000). Multivariate analysis shows the dependence of both biomarkers only on K-L Grades. ROC analysis suggests cutoff value between KL Grade 0 and Grade I (MMP-3: 12.25 ng/mL; CTX II: 407.50 pg/mL) and between K L Grade I and Grade II (MMP-3: 18.37 ng/mL; CTX II: 528.00 pg/mL). The discriminating ability of CTX II is superior between normal population and eKOA (CTX II: Accuracy: 66.83%, p = 0.0002; MMP-3: Accuracy: 50.39%, p = 0.138), but MMP-3 is superior than CTX II between eKOA and mild KOA (CTX II:67.52%, p < 0.000; MMP-3: 70.69%, p < 0.000).

CODD-Pred: A Web Server for Efficient Target Identification and Bioactivity Prediction of Small Molecules

Target identification and bioactivity prediction are critical steps in the drug discovery process. Here we introduce CODD-Pred (COmprehensive Drug Design Predictor), an online web server with well-curated data sets from the GOSTAR database, which is designed with a dual purpose of predicting potential protein drug targets and computing bioactivity values of small molecules. We first designed a double molecular graph perception (DMGP) framework for target prediction based on a large library of 646 498 small molecules interacting with 640 human targets. The framework achieved a top-5 accuracy of over 80% for hitting at least one target on both external validation sets. Additionally, its performance on the external validation set comprising 200 molecules surpassed that of four existing target prediction servers. Second, we collected 56 targets closely related to the occurrence and development of cancer, metabolic diseases, and inflammatory immune diseases and developed a multi-model self-validation activity prediction (MSAP) framework that enables accurate bioactivity quantification predictions for small-molecule ligands of these 56 targets. CODD-Pred is a handy tool for rapid evaluation and optimization of small molecules with specific target activity. CODD-Pred is freely accessible at http://codd.iddd.group/.

Relationship between knee osteophytes and calcitonin gene-related peptide concentrations of serum and synovial fluid in knee of osteoarthritis

To explore the relationship between knee osteophytes of osteoarthritic knee and calcitonin gene-related peptide (CGRP) concentrations of serum and synovial fluid (SF). 65 patients with knee medial compartment osteoarthritis (OA) were recruited and examined with weight-bearing radiographs of the entire lower limb. The concentrations of CGRP in serum/SF were also detected in surgery. The relationship between the concentrations of CGRP in serum/SF and osteophyte scores were detected with Spearman rank correlation coefficient. CGRP concentrations in serum and SF were significantly correlated with osteophyte score of overall knee respectively (R = 0.462, P < .001; R = 0.435, P < .001). In addition, a correlation tended to be observed about the relationship between CGRP concentrations in serum and SF and osteophyte scores of medial compartment (R = 0.426, P < .001; R = 0.363, P = .003), and osteophyte scores of lateral compartment (R = 0.429, P < .001; R = 0.444, P < .001). In this study, the relationship between CGRP in serum/SF and knee osteophyte scores in different subregions were explored, which showed significant positive correlations, that possibly reflecting the contribution of CGRP influencing osteophyte formation. Positive correlations between osteophyte scores and CGRP suggest that CGRP promote the growth of osteophyte formation. It has the potential to be selected as a biomarker for the assessment of severity in knee OA patients and predict the progression of knee OA. It also provides a potential therapeutic target to delay the progression and relieve the symptom of OA.

Research Progress on the Pathogenesis of Knee Osteoarthritis

Knee osteoarthritis (KOA) is a chronic joint bone disease characterized by inflammatory destruction and hyperplasia of bone. Its main clinical symptoms are joint mobility difficulties and pain, severe cases can lead to limb paralysis, which poses major pressure to the quality of life and mental health of patients, but also brings serious economic burden to society. The occurrence and development of KOA is influenced by many factors, including systemic factors and local factors. The joint biomechanical changes caused by aging, trauma and obesity, abnormal bone metabolism caused by metabolic syndrome, the effects of cytokines and related enzymes, genetic and biochemical abnormalities caused by plasma adiponectin, etc. all directly or indirectly lead to the occurrence of KOA. However, there is little literature that systematically and comprehensively integrates macro- and microscopic KOA pathogenesis. Therefore, it is necessary to comprehensively and systematically summarize the pathogenesis of KOA in order to provide a better theoretical basis for clinical treatment.

Cartilage regeneration and inflammation modulation in knee osteoarthritis following injection of allogeneic adipose-derived mesenchymal stromal cells: a phase II, triple-blinded, placebo controlled, randomized trial

BACKGROUND

Intra-articular injection of mesenchymal stromal cells (MSCs) with immunomodulatory features and their paracrine secretion of regenerative factors proposed a noninvasive therapeutic modality for cartilage regeneration in knee osteoarthritis (KOA).

METHODS

Total number of 40 patients with KOA enrolled in two groups. Twenty patients received intra-articular injection of 100 × 10⁶ allogeneic adipose-derived mesenchymal stromal cells (AD-MSCs), and 20 patients as control group received placebo (normal saline). Questionnaire-based measurements, certain serum biomarkers, and some cell surface markers were evaluated for 1 year. Magnetic resonance imaging (MRI) before and 1 year after injection was performed to measure possible changes in the articular cartilage.

RESULTS

Forty patients allocated including 4 men (10%) and 36 women (90%) with average age of 56.1 ± 7.2 years in control group and 52.8 ± 7.5 years in AD-MSCs group. Four patients (two patients from AD-MSCs group and two patients from the control group) excluded during the study. Clinical outcome measures showed improvement in AD-MSCs group. Hyaluronic acid and cartilage oligomeric matrix protein levels in blood serum decreased significantly in patients who received AD-MSCs (P < 0.05). Although IL-10 level significantly increased after 1 week (P < 0.05), the serum level of inflammatory markers dramatically decreased after 3 months (P < 0.001). Expressions of CD3, CD4, and CD8 have a decreasing trend during 6-month follow-up (P < 0.05), (P < 0.001), and (P < 0.001), respectively. However, the number of CD25⁺ cells increased remarkably in the treatment group 3 months after intervention (P < 0.005). MRI findings showed a slight increase in the thickness of tibial and femoral articular cartilages in AD-MSCs group. The changes were significant in the medial posterior and medial anterior areas of ​​the tibia with P < 0.01 and P < 0.05, respectively.

CONCLUSION

Inter-articular injection of AD-MSCs in patients with KOA is safe. Laboratory data, MRI findings, and clinical examination of patients at different time points showed notable articular cartilage regeneration and significant improvement in the treatment group.

TRIAL REGISTRATION

Iranian registry of clinical trials (IRCT, https://en.irct.ir/trial/46 ), IRCT20080728001031N23. Registered 24 April 2018.

Can serum MMP-3 diagnose early knee osteoarthritis?

Aims

This study aims to assess the ability of serum MMP-3 levels to differentiate between normal knee with primary knee osteoarthritis (KOA) and its ability to differentiate between various severity grades.

Material & methods

The study included 80 cases of primary knee osteoarthritis (KOA) and 80 young individuals with no features of KOA.

Results

The subjects in Case group were younger (52.80 ± 10.31 years) than in Control group (28.55 ± 5.98 years) (p = 0.001). The BMI of Case group (27.5 ± 4.81 kg/m2) was significantly higher than in Control group (25.40 ± 5.71 kg/m2) (p = 0.012). Mean sMMP-3 level in Cases (59.85 ± 39.92 ng/ml) was significantly higher than in Controls (14.52 ± 6.09 ng/ml) (p = 0.0001). There was no gender difference in biomarker values in Cases (p = 0.1) and in Controls (p = 0.88). The level of sMMP-3 rises with increasing age in cases only (p = 0.0001). MMP-3 values were significantly elevated in cases in the sub-categories of BMI within case group and control group (>0.05) but higher in cases in normal, overweight and obese subcategories (p < 0.05). Serum MMP-3 level differs significantly between K-L grade 0-I (p = 0.004), K-L grade I-II (p = 0.000), K-L grade II-III (p = 0.007) and also between K-L grade III-IV (p = 0.02). Biomarker showed moderate positive correlation with KL grade (r = 0.68, p = 0.000) and age (r = 0.38, p = 0.000) and weak positive correlation with WOMAC score (r = 0.289, p = 0.009). The receiver operative curve (ROC) analysis suggested a cut off value of sMMP-3 as 20.03 ng/ml between Control group and Case group, as 12.25 ng/ml between K-L grade 0-I; as 18.37 ng/ml between K-L grade I-II; as 55.60 ng/ml between K-L grade II-III; as 102.0 ng/ml between K-L grade III-IV.

Conclusions

sMMP-3 estimation as a tool has a good discriminatory power to differentiate between healthy and a diseased knee (KOA) and between severity grades. It can be used as a test to identify individuals with KL grade I and II of KOA.

Transcriptomic analyses of joint tissues during osteoarthritis development in a rat model reveal dysregulated mechanotransduction and extracellular matrix pathways

OBJECTIVE

Transcriptomic changes in joint tissues during the development of osteoarthritis (OA) are of interest for the discovery of biomarkers and mechanisms of disease. The objective of this study was to use the rat medial meniscus transection (MMT) model to discover stage and tissue-specific transcriptomic changes.

DESIGN

Sham or MMT surgeries were performed in mature rats. Cartilage, menisci and synovium were scored for histopathological changes at 2, 4 and 6 weeks post-surgery and processed for RNA-sequencing. Differentially expressed genes (DEG) were used to identify pathways and mechanisms. Published transcriptomic datasets from animal models and human OA were used to confirm and extend present findings.

RESULTS

The total number of DEGs was already high at 2 weeks (723 in meniscus), followed by cartilage (259) and synovium (42) and declined to varying degrees in meniscus and synovium but increased in cartilage at 6 weeks. The most upregulated genes included tenascins. The 'response to mechanical stimulus' and extracellular matrix-related pathways were enriched in both cartilage and meniscus. Pathways that were enriched in synovium at 4 weeks indicate processes related to synovial hyperplasia and fibrosis. Synovium also showed upregulation of IL-11 and several MMPs. The mechanical stimulus pathway included upregulation of the mechanoreceptors PIEZO1, PIEZO2 and TRPV4 and nerve growth factor. Analysis of data from prior RNA-sequencing studies of animal models and human OA support these findings.

CONCLUSION

These results indicate several shared pathways that are affected during OA in cartilage and meniscus and support the role of mechanotransduction and other pathways in OA pathogenesis.

Soluble and EV-Associated Diagnostic and Prognostic Biomarkers in Knee Osteoarthritis Pathology and Detection

Osteoarthritis (OA) is the most common degenerative disease of the connective tissue of the human musculoskeletal system. Despite its widespread prevalence, there are many limitations in its diagnosis and treatment. OA diagnosis currently relies on the presence of clinical symptoms, sometimes accompanied by changes in joint X-rays or MRIs. Biomarkers help not only to diagnose early disease progression but also to understand the process of OA in many ways. In this article, we briefly summarize information on articular joints and joint tissues, the pathogenesis of OA and review the literature about biomarkers in the field of OA, specifically inflammatory cytokines/chemokines, proteins, miRNA, and metabolic biomarkers found in the blood, synovial fluid and in extracellular vesicles.

The Diagnostic and Prognostic Value of Synovial Fluid Analysis in Joint Diseases

Liquid biopsy is an emergent test method for the diagnosis and prognosis in the clinic. Joint fluid, also known as synovial fluid, contains a variety of bioactive constituents that can be selectively detected and further evaluated in a convenient fashion. Therefore, synovial fluid analysis functions as a specific form of liquid biopsy and plays a vital role in numerous joint diseases. In spite of the component analysis of aspirated synovial fluid beingconsidered as the gold standard for diagnosis of joint infections, biopsy of joint fluid benefits the initial diagnosis and long-term prognosis of degenerative, inflammatory, autoimmune, traumatic, congenital, and even neoplastic joint diseases. The convenience and accuracy for disease evaluation are significantly elevated as a result of the combination of synovial fluid analysis and other novel clinical technologies. In this review, we shed light on the latent role of synovial fluid in the diagnosis and prognosis of articular diseases and proposed future prospects for relevant research in this field.

[Developments in Research on the Relationship Between Matrix Metalloproteinases and Osteoarthritis]

Matrix metalloproteinases (MMPs) acquired their names because they depend on metal ions such as Ca 2+ and Zn 2+ as their cofactors. Members of this family of proteins share a similar structure consisting of five functionally distinct structural domains. MMPs, including MMP-1, MMP-3, MMP-9, and MMP-13, are key substances that promote cartilage matrix degradation and play an important role in the occurrence and progression of osteoarthritis (OA). MMPs boost the development of OA through the degradation of extracellular matrix proteins of chondrocytes, the promotion of inflammation, and other mechanisms, and are hence attracting extensive and increasing attention from the medical community. OA is a common degenerative disease that occurs in the joints and is associated with aging, metabolism, infections, genetics, exercise, and other predisposing factors. The pathological changes it causes can lead to a series of clinical symptoms such as joint pain, morning stiffness, and restricted joint movement, severely affecting patients' quality of life. The pathogenic mechanism of this highly prevalent disease is still unclear. At present, there is no effective treatment available for disease improvement. In the future, selective inhibition of MMPs, the key enzymes, may become an effective therapeutic approach. Focusing on the pathogenic effects of MMPs in OA, we herein reviewed the latest findings on the role of MMPs in the occurrence and progression of OA.

Efficacy of sCOMP and sCTX-I in Diagnosis of Knee Osteoarthritis

OBJECTIVE

The aim of this study was to evaluate the efficacy of serum cartilage oligomeric matrix protein (sCOMP) and  serum C-terminal cross-linked telopeptide of type I collagen (sCTX-I) in identifying disease severity in knee osteoarthritis (KOA) cases.

METHODS

A total of 150 individuals (100 cases and 50 controls) were recruited. They were assessed clinically and radiologically with WOMAC score and knee radiographs respectively, while biochemical assessment was done by serum COMP and serum CTX-I level.

RESULTS

There were significant differences in serum levels between healthy individuals and KOA patients of both, sCOMP (01.16 ± 0.39 vs 17.38 ± 4.99 U/L; p = 0.01) and sCTX-I (0.35 ± 0.14 vs 4.59 ± 1.69; p = 0.02). There was a statistically significant difference between serum levels of CTX-I between K-L grade I and grade II (4.59 ± 1.69 vs 4.60 ± 1.17 ng/mL; p = 0.03) but no significant difference was seen in the sCOMP levels between K-L grade I and grade II (14.60 ± 6.47 vs 17.47 ± 4.99 U/L; p = 0.14).

CONCLUSION

Our findings reveal that both sCOMP and sCTX-I are very effective in distinguishing between healthy adults and those affected by KOA. Only CTX-I was also able to distinguish between K-L grades I and II, while sCOMP failed. Further, use of these two biomarkers to differentiate between K-L grade II, III and IV is limited and lacks sufficient discriminating power, hence not recommended.

Changes in the Synovial Fluid Cytokine Profile of the Knee Between an Acute Anterior Cruciate Ligament Injury and Surgical Reconstruction

BACKGROUND

Changes in the intra-articular inflammatory state during the immediate period after an acute anterior cruciate ligament (ACL) rupture are not well defined.

PURPOSE

To evaluate changes in the concentration of select proinflammatory and anti-inflammatory synovial fluid cytokines during the interval between an ACL injury and surgical reconstruction.

STUDY DESIGN

Descriptive laboratory study.

METHODS

In patients with an acute ACL injury, a synovial fluid sample was obtained from the injured knee during the initial office visit within 2 weeks of the inciting traumatic event. An additional synovial fluid sample was collected at the time of ACL reconstruction just before the surgical incision. Synovial fluid samples from both the acute injury and the surgery time points were processed with a protease inhibitor, and the concentrations of 10 cytokines of interest were measured using a multiplex magnetic bead immunoassay. The primary outcome was the change in cytokine concentrations between time points.

RESULTS

A total of 20 patients with a mean age of 30.2 ± 8.3 years were included. The acute injury synovial fluid samples were collected at 6.6 ± 3.8 days after the injury. The surgical synovial fluid samples were collected at 31.6 ± 15.6 days after the acute injury samples. Based on a series of linear mixed-effects models to control for the effect of concomitant meniscal injuries and by-patient variability, there was a statistically significant increase in the concentrations of RANTES and bFGF and a statistically significant decrease in the concentrations of IL-6, MCP-1, MIP-1β, TIMP-1, IL-1Ra, and VEGF between time points.

CONCLUSION

This study demonstrates the ongoing alterations in the intra-articular microenvironment during the initial inflammatory response in the acute postinjury period. We identified 6 synovial fluid cytokines that significantly decreased and 2 that significantly increased between the first clinical presentation shortly after the injury and the time of surgery 1 month later.

CLINICAL RELEVANCE

This study describes the molecular profile of the inflammatory changes between the time of an acute ACL injury and the time of surgical reconstruction 1 month later. A greater understanding of the acute inflammatory response within the knee may be helpful in identifying the optimal timing for a surgical intervention that balances the risk of chondral damage with the likelihood of successful, well-healed reconstruction.

Effects of Exercise Training Alone and in Combination With Kinesio Taping on Pain, Functionality, and Biomarkers Related to the Cartilage Metabolism in Knee Osteoarthritis

OBJECTIVE

To investigate the effects of exercise training alone and in combination with kinesio taping on pain, functionality, and circulating cartilage oligomeric matrix protein (COMP), and matrix metalloproteinase (MMP)-1, and -3 at rest and immediately after walking exercise in knee osteoarthritis (OA).

DESIGN

A total of 22 female patients diagnosed with knee OA were randomly divided into the exercise training (ET) or exercise training plus kinesio taping (ET + KT) groups. The patients in the ET performed exercise training for 6 weeks. The patients in the ET + KT group were applied with kinesio tape in addition to the exercise training for 6 weeks. In both groups, 20 minutes of walking exercise were performed before and after the interventions. The pain and functional status of the patients were assessed using visual analogue scale (VAS) and Western Ontario McMasters Osteoarthritis Index (WOMAC) before and after the intervention at rest, respectively. Blood samples were taken at rest and immediately after the walking exercise before and after the interventions for the analysis of COMP, MMP-1, and MMP-3 levels.

RESULTS

In both groups, pain and functionality scores were significantly improved after the interventions (P < 0.05). COMP, MMP-1 and MMP-3 levels were higher immediately after walking exercise when compared with rest in both groups before and after the intervention (P < 0.05).

CONCLUSIONS

Exercise training and exercise training plus kinesio taping improved pain and physical function; however, the COMP, MMP-1, and MMP-3 levels did not change.

Vicenin 3 ameliorates ECM degradation by regulating the MAPK pathway in SW1353 chondrocytes

Aberrant destruction of the articular extracellular matrix (ECM) has been considered to be one of the pathological features of osteoarthritis (OA) which results in chondrocyte changes and articular cartilage degeneration. The MAPK signaling pathway serves a key role by releasing cartilage-degrading enzymes from OA chondrocytes. However, the use of MAPK inhibitors for OA is hindered by their potential long-term toxicity. Vicenin 3 is one of the major components of the Jian-Gu injection which is effective in the clinical treatment of OA. However, its potential impact on OA remain poorly understood. Therefore, the present study aimed to assess the effects of vicenin 3 on interleukin (IL)-1β-treated SW1353 chondrocytes, which mimic the microenvironment of OA. These chondrocytes were pretreated with vicenin 3 (0, 5 and 20 µM) for 1 h and subsequently stimulated with IL-1β (10 ng/ml) for 24 h. Nitric oxide (NO) production was measured using the Griess reaction, whereas the production of prostaglandin E2 (PGE2), matrix metalloproteinases (MMPs), A disintegrin-like and metalloproteinase with thrombospondin motifs (ADAMTSs), collagen type II and aggrecan were measured using ELISA. The mRNA expression of MMPs and ADAMTSs were measured using reverse transcription-quantitative PCR. The protein expression levels of MAPK were measured using western blotting. Vicenin 3 was found to significantly inhibit IL-1β-induced production of NO and PGE. Increments in the expression levels of MMP-1, MMP-3, MMP-13, ADAMTS-4 and ADAMTS-5 induced by IL-1β, in addition to the IL-1β-induced degradation of collagen type II and aggrecan, were all reversed by vicenin 3 treatment. Furthermore, vicenin 3 suppressed IL-1β-stimulated MAPK activation, an effect that was similar to that exerted by SB203580, a well-known p38 MAPK inhibitor. In conclusion, vicenin 3 may confer therapeutic potential similar to that of the p38 MAPK inhibitor for the treatment of OA.

Biomarkers of Joint Damage in Osteoarthritis: Current Status and Future Directions

Osteoarthritis (OA) is a disease of the whole joint organ, characterized by the loss of cartilage, and structural changes in bone including the formation of osteophytes, causing disability and loss of function. It is also associated with systemic mediators and low-grade inflammation. Currently, there is negligible/no availability of specific biomarkers that can be used to facilitate the diagnosis and treatment of OA. The most unmet clinical need is, however, related to the monitoring of disease progression over a short period that can be used in clinical trials. In this review, the value of biomarkers identified over the past decade has been highlighted. These biomarkers are associated with the synthesis and breakdown of cartilage, including collagenous and noncollagenous biomarkers, inflammatory and anti-inflammatory biomarkers, expressed in the biological fluid such as serum, synovial fluid, and urine. Broad validation of novel and clinically applicable biomarkers and their involvement in the pathways are particularly needed for early-stage diagnosis, monitoring disease progression, and severity and examining new drugs to mitigate the effects of this highly prevalent and debilitating condition.