OBJECTIVE: To investigate the relationship between trace elements in synovial fluid and cartilage and severity of knee osteoarthritis (KOA). METHODS: Patients with KOA who underwent knee arthrocentesis or total knee arthroplasty (TKA) were recruited based on inclusion criteria between June 2021 and December 2021. Synovial fluid samples were obtained during knee arthrocentesis and TKA, and participants were divided into the mild group (grading Ⅰ/Ⅱ) and the severe group (grading Ⅲ/Ⅳ) according to the Kellgren-Lawrence grading (K-L grading). Cartilage samples with different degrees of wear were collected during the TKA from the same patient and were divided into mild wear (0-1 point) and severe wear (2-4 points) groups based on the Pelletier score. The contents of copper (Cu), zinc (Zn), and manganese (Mn) in synovial fluid and cartilage were evaluated by inductively coupled plasma mass spectrometry, and the differences between groups were compared. RESULTS: A total of 33 synovial fluid samples were collected, including 19 specimens from 14 patients who underwent knee arthrocentesis of mild group, with 5 bilateral sides knee arthrocentesis in them, and 14 specimens from 14 TKA patients of severe group. The patients were significantly younger in the mild group than in the severe group ( P<0.05), but there was no significant difference in gender or body mass index between the two groups ( P>0.05). Nineteen pairs of cartilage samples with mild and severe wear were collected from severe KOA patients (K-L grading Ⅲ and Ⅳ), including 9 males and 10 females, with an average age of 70.4 years (range, 58-80 years). The body mass index ranged from 21.2 to 30.7 kg/m ², with an average of 25.6 kg/m ². The content of Zn in synovial fluid and cartilage from KOA patients was the highest, followed by Cu, and Mn was the lowest. The Cu content in synovial fluid was significantly higher in the severe group than in the mild group ( P<0.05), and in the severe wear group than in the mild wear group ( P<0.05). There was no significant difference in Zn and Mn content between the two groups ( P>0.05). CONCLUSION The Cu content increases with the severity of cartilage wear in patients with KOA.
Male ; Female ; Humans ; Aged ; Osteoarthritis, Knee/surgery* ; Synovial Fluid ; Trace Elements ; Knee Joint/surgery* ; Cartilage, Articular ; Zinc

Objective To identify the potential long non-coding RNA (lncRNA) expressed in rheumatoid arthritis (RA) synovium key to RA onset and investigate its association with immune cell infiltration. Methods RA synovium data were downloaded from the GEO database and normalized. The lncRNAs key to RA onset were identified using multiple machine learning methods. Infiltration of 22 immune cell populations in RA synovium was measured by cell-type identification by estimating relative subsets of RNA transcripts (CIBER-SORT). The relationship between the key lncRNA and infiltrating immune cells was analyzed. Finally, real-time quantitative PCR was applied to validate the expression of the key lncRNA in RA synovial cells. Results lncRNA human leukocyte antigen complex P5(HCP5) was identified as the key lncRNA associated with RA onset. Infiltration analysis revealed increased abundance of CD8⁺ T cells, γδ T cells, and M1 macrophages while decreased abundance of M2 macrophages in RA synovial tissue. Correlation analysis demonstrated that the lncRNA HCP5 expression was positively associated with the infiltration abundance of CD8⁺ T cells, γδ T cells, and M1 macrophages in RA synovial tissue. Furthermore,the expression of lncRNA HCP5 in RA synovial cells was up-regulated. Conclusion lncRNA HCP5 expression is up-regulated in RA synovial tissue and potentially associated with immune cells infiltration.
Humans ; Arthritis, Rheumatoid ; CD8-Positive T-Lymphocytes ; HLA Antigens/metabolism* ; RNA, Long Noncoding/metabolism* ; Synovial Membrane/metabolism*

Humans ; Synovial Fluid ; MicroRNAs/genetics* ; Exosomes/genetics* ; Osteoarthritis/genetics* ; Synovial Membrane

OBJECTIVES: Rheumatoid arthritis (RA) is a chronic autoimmune disease. MicroRNA has been shown to play an important role in RA. MicroRNA-124a (miR-124a) has anti-proliferative and anti-inflammatory effects in RA fibroblast synovial cells. This study aims to explore the effects of miR-124a overexpression on arthritis in collagen-induced arthritis (CIA) mice and the underlying mechanisms. METHODS: Bovine type II collagen and complete Ferris adjuvant were used to induce CIA model from DBA/1 mice. Twenty-eight days after initial immunization (D28), CIA mice were randomly divided into a model group, a miR-124a treatment group, and a negative control (NC) group. Physiological saline, miR-124a agomir, and miR-124a agomir NC were injected into the skin at the tail root of mice every 3 days for 4 times, respectively. The degree of joint swelling and arthritis index of mice were recorded accordingly. Sixty-three days after initial immunization (D63), the mice were sacrificed to obtain the synovial tissue of ankle joint. HE staining was used to observe the proliferation of synovial cell, infiltration of inflammatory cell, pannus, and bone erosion of synovial tissues; TUNEL staining was used to detect cell apoptosis; qRT-PCR was used to detect the mRNA expression of miR-124a, phosphatidylinositol-3-kinase catalytic subunit alpha (PIK3CA) and its downstream genes Bcl-2 and Bax. Immunohistochemistry was used to detect the protein expression of PIK3CA, Bcl-2, and Bax protein in synovial tissues of each group. RESULTS: Different degrees of swelling presented in the paws of DBA/1 mice at D28, which indicated the CIA model was constructed successfully. Forty-eight days after initial immunization (D48), the paws of mice in the miR-124a treatment group were only slightly red and swollen, while the paws of mice in the model group and the NC group were obviously red and swollen. The arthritis index of mice in the miR-124a treatment group were decreased significantly compared to the NC group at D51, D53, D59, and D62 (51, 53, 59, 62 days after initial immunization) (all P<0.05). Sixty-three days after initial immunization (D63), HE staining indicated that the scores of synovial cell proliferation, inflammatory cell infiltration, synovial pannus, and bone erosion were significantly reduced in the miR-124a treatment group (P<0.05 or P<0.01), while cell apoptosis was increased in the miR-124a treatment group compared with the model group and NC group (P<0.01 or P<0.001). Besides, the expression of miR-124a and Bax in the synovial tissue in miR-124a treatment group was significantly higher than those in the model group and NC group (P<0.01 or P<0.001), while the expressions of PIK3CA and Bcl-2 were decreased (P<0.05 or P<0.01 or P<0.001), and the ratio of Bcl-2 to Bax was significantly decreased (P<0.01 or P<0.001). CONCLUSIONS Overexpression of miR-124a can reduce arthritis in CIA mice bacause it could promote synovial cell apoptosis and inhibit synovial cell proliferation via targeting PIK3CA and regulating its downstream pathways.
Animals ; Arthritis, Experimental/metabolism* ; Arthritis, Rheumatoid/genetics* ; Cattle ; Cell Proliferation ; Class I Phosphatidylinositol 3-Kinases/metabolism* ; Mice ; Mice, Inbred DBA ; MicroRNAs/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Synovial Membrane ; bcl-2-Associated X Protein/metabolism*

OBJECTIVE: To investigate the effect of triptolide (TPL) on inflammatory response and migration of fibroblast like synovial cells (FLS) in rheumatoid arthritis (RA-FLS) and the mechanism of circular noncoding RNA (circRNA) 0003353 for mediating this effect. METHODS: We collected peripheral blood mononuclear cells (PBMCs) and serum samples from 50 hospitalized RA patients and 30 healthy individuals for detecting the expression of circRNA 0003353, immune and inflammatory indexes (ESR, CRP, RF, anti-CCP, IgA, IgG, IgM, C3, and C4) and DAS28 score. Cultured RA-FLS was treated with 10 ng/mL TPL and transfected with a circRNA 0003353 overexpression plasmid, and cell counting kit-8 (CCK-8) assay and Transwell assay were used to detect the changes in the viability and migration of the cells. Enzyme-linked immunosorbent assay (ELISA) was used to examine the cytokines IL-4, IL-6, and IL-17, and real-time fluorescence quantitative PCR (RT-qPCR) was performed to detect the expression of circRNA 003353; Western blotting was used to detect the expressions of p-JAK2, pSTAT3, JAK2 and STAT3 proteins in the treated cells. RESULTS: The expression of circRNA 0003353 was significantly increased in PBMCs from RA patients and showed a good performance in assisting the diagnosis of RA (AUC=90.5%, P < 0.001, 95% CI: 0.83-0.98). CircRNA 0003353 expression was positively correlated with ESR, RF and DAS28 (P < 0.05). Treatment with TPL significantly decreased the expression of circRNA 0003353, suppressed the viability and migration ability, decreased the expressions of IL-6 and IL-17, and increased the expression IL-4 in cultured RA-FLS in a time-dependent manner (P < 0.01). TNF-α stimulation of RA-FLS significantly increased the ratios of p-JAK2/JAK2 and p-STAT3/STAT3, which were obviously lowered by TPL treatment (P < 0.01). TPL-treated RA-FLS overexpressing circRNA 0003353 showed significantly increased cell viability and migration ability with decreased IL-4 expression and increased IL-6 and IL-17 expressions and ratios of p-JAK2/ JAK2 and p-STAT3/STAT3 (P < 0.01). CONCLUSION The expression of circRNA 0003353 is increased in PBMCs in RA patients and in RA-FLS. TPL treatment can regulate JAK2/STAT3 signal pathway and inhibit the inflammatory response and migration of RA-FLS through circRNA 0003353.
Arthritis, Rheumatoid/pathology* ; Cells, Cultured ; Diterpenes/pharmacology* ; Epoxy Compounds/pharmacology* ; Fibroblasts/pathology* ; Humans ; Interleukin-17/metabolism* ; Interleukin-4/metabolism* ; Interleukin-6/metabolism* ; Janus Kinase 2/metabolism* ; Leukocytes, Mononuclear/metabolism* ; Phenanthrenes/pharmacology* ; RNA, Circular/metabolism* ; STAT3 Transcription Factor/metabolism* ; Signal Transduction/drug effects* ; Synovial Membrane/pathology*

OBJECTIVE: To examine the expression of chemokine receptor CCR10 on monocytes/macrophages in the joints of patients with rheumatoid arthritis (RA), and to investigate the role of chemokine CCL28 and its receptor CCR10 in the migration of RA monocytes and its mechanism. METHODS: The expression of CCR10 in synovial tissues from 8 RA patients, 4 osteoarthritis (OA) patients, and 4 normal controls was analyzed by immunohistochemistry, and cell staining was scored on a 0-5 scales. Flow cytometry was used to measure the percentage of CCR10 positive cells in CD14⁺ monocytes from peripheral blood of 26 RA patients and 20 healthy controls, as well as from synovial fluid of 15 RA patients. The chemotactic migration of monocytes from RA patients and healthy controls in response to CCL28 was evaluated using an in vitro Transwell system. Western blotting was conducted to assess phosphorylation of the extracellular signal-regulated kinase (ERK) and protein kinase B (Akt) pathways in RA monocytes upon CCL28 treatment. RESULTS: CCR10 was predominantly expressed in RA synovial lining cells and sublining macrophages, endothelial cells, and lymphocytes. CCR10 expression was significantly increased on lining cells and sublining macrophages in RA synovial tissue compared with OA and normal synovial tissue (both P < 0.01). The patients with RA had markedly elevated expression of CCR10 on peripheral blood CD14⁺ monocytes compared with the healthy controls [(15.6±3.0)% vs. (7.7±3.8)%, P < 0.01]. CCR10 expression on synovial fluid monocytes from the RA patients was (32.0±15.0)%, which was significantly higher than that on RA peripheral blood monocytes (P < 0.01). In vitro, CCL28 caused significant migration of CD14⁺ monocytes from peripheral blood of the RA patients and the healthy controls at concentrations ranging from 10-100 μg/L (all P < 0.01). The presence of neutralizing antibody to CCR10 greatly suppressed CCL28-driven chemotaxis of RA monocytes (P < 0.01). Stimulation of RA monocytes with CCL28 induced a remarkable increase in phosphorylation of ERK and Akt (both P < 0.05). ERK inhibitor (U0126) and phosphatidylinositol 3-kinase (PI3K) inhibitor (LY294002) strongly reduced the migration of RA monocytes in response to CCL28 (both P < 0.01). CONCLUSION RA patients had increased CCR10 expression on peripheral blood, synovial fluid, and synovial tissue monocytes/macrophages. CCL28 ligation to CCR10 promoted RA monocyte migration through activation of the ERK and PI3K/Akt signaling pathways. The CCL28-CCR10 pathway could participate in monocyte recruitment into RA joints, thereby contributing to synovial inflammation and bone destruction.
Humans ; Monocytes/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Endothelial Cells/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Arthritis, Rheumatoid ; Synovial Membrane ; Chemokines, CC/metabolism* ; Synovial Fluid ; Osteoarthritis ; Receptors, CCR10/metabolism*

The aim of this paper was to observe the effect of Xinfeng Capsules(XFC)-containing serum on the apoptosis and inflammation of fibroblast-like synoviocytes(FLS) in rheumatoid arthritis(RA) induced by tumor necrosis factor-α(TNF-α), so as to investigate the mechanism of XFC in the treatment of RA. RA-FLS immortalized cell line was established, and XFC drug-containing serum was prepared. CCK-8, ELISA, RT-qPCR, immunofluorescence and TUNEL were used to observe the effect of XFC-containing serum on RA-FLS apoptosis and inflammatory indexes. CCK-8 results showed that the optimal concentration and time of TNF-α on RA-FLS were 10 ng·mL~(-1) and 48 h, respectively; and the optimal concentration and time of XFC on RA-FLS were 6.48 mg·g~(-1) and 72 h, respectively. The results of ELISA showed that compared with RA-FLS group, the expressions of TNF-α, IL-1β, IL-6, IL-8 in TNF-α+RA-FLS group were significantly increased, while the expressions of IL-4 and IL-10 were significantly decreased(P<0.01); after intervention with XFC-containing serum, the expressions of TNF-α, IL-1β, IL-6, IL-8 were significantly decreased, whereas the expressions of IL-4 and IL-10 were significantly increased(P<0.01). The results of RT-qPCR showed that compared with RA-FLS group, the mRNA expressions of Fas, FasL, caspase-3, caspase-8, Bax, Bcl-X1 in TNF-α+RA-FLS group were significantly decreased, while the mRNA expression of Bcl-2 was significantly increased(P<0.001); after intervention with XFC-containing serum, the mRNA expressions of Fas, FasL, caspase-3, caspase-8, Bax, Bcl-X1 were significantly increased, whereas the mRNA expression of Bcl-2 was significantly decreased(P<0.01). The results of immunofluorescence showed that compared with RA-FLS group, the protein expressions of caspase-3 and Bax in TNF-α+RA-FLS group was significantly lower than those in RA-FLS group(P<0.05); after intervention with XFC-containing serum, the protein expressions of caspase-3 and Bax were significantly increased, whereas the protein expression of Bcl-2 was significantly decreased(P<0.05). TUNEL results showed that compared with RA-FLS group, the apoptosis of TNF-α+RA-FLS group was decreased(P<0.05); after intervention with XFC-containing serum, the apoptosis was significantly increased(P<0.05). One of the mechanisms of XFC in the treatment of RA is to promote the apoptosis of RA-FLS and inhibit its inflammatory reaction.
Apoptosis ; Arthritis, Rheumatoid/genetics* ; Capsules ; Cells, Cultured ; Drugs, Chinese Herbal ; Fibroblasts ; Humans ; Inflammation ; Synovial Membrane ; Synoviocytes ; Tumor Necrosis Factor-alpha/genetics*

OBJECTIVE: To detect the expression of cartilage oligomeric matrix protein (COMP) in the synovial chondromatosis of the temporomandibular joint (TMJSC), and to discuss the possible interactions between COMP, transforming growth factor (TGF)-β3, TGF-β1 and bone morphogenetic protein-2 (BMP-2) in the development of this neoplastic disease. METHODS: Patients in Peking University School and Hospital of Stomatology from January 2011 to February 2020 were selected, who had complete medical records, TMJSC was verified histologically after operation. The expressions of COMP, TGF-β3, TGF-β1 and BMP-2 in the TMJSC of the temporomandibular joint were detected by immunohistochemistry and quantitative real-time PCR (RT-PCR) at the protein level and mRNA level respectively, compared with the normal synovial tissue of temporomandibular joint. The histological morphology, protein expression and distribution of TMJSC tissues were observed microscopically, and the positive staining proteins were counted and scored. SPSS 22.0 statistical software was used to analyze the expression differences between the related proteins in TMJSC tissue and the normal synovial tissue of temporomandibular joint and to compare their differences. P < 0.05 indicated that the difference was statistically significant. RESULTS: Immunohistochemical results showed that the positive expression of COMP in TMJSC tissues was mostly found in synovial tissues and chondrocytes adjacent to synovial tissues, and the difference was statistically significant, compared with the normal temporomandibular joint synovial tissues. The positive expression of COMP was significantly different between recurrent TMJSC and non-recurrent ones. The positive expressions of TGF-β3, TGF-β1 and BMP-2 were higher than the normal synovial tissue, and were also mostly found in the synovial cells and adjacent chondrocytes, which was further confirmed by Western blot. According to the RT-PCR results, the expressions of COMP, TGF-β3, TGF-β1 and BMP-2 in TMJSC were higher than those in the normal synovial tissue. CONCLUSION The expression of COMP in TMJSC of temporomandibular joint increased significantly, compared with the normal synovial tissue. There may be interactions between COMP and cytokines related to the proliferation and differentiation, like TGF-β3, TGF-β1 and BMP-2, which may play a potential role in the pathogenesis of TMJSC.
Cartilage Oligomeric Matrix Protein/genetics* ; Chondromatosis, Synovial ; Humans ; Synovial Membrane ; Temporomandibular Joint ; Transforming Growth Factor beta3

OBJECTIVE: To observe the therapeutic effects of different waves of electroacupuncture (EA) on knee osteoarthritis (KOA), and to explore the mechanism of different waves of EA on promoting cartilage repair. METHODS: Ninety- seven patients with KOA were randomly divided into a dilatational wave group (32 cases, 2 cases dropped off), a continuous wave group (32 cases, 2 cases dropped off) and a discontinuous wave group (33 cases, 3 cases dropped off). The same acupoints of Xuehai (SP 10), Liangqiu (ST 34), Dubi (ST 35) and Neixiyan (EX-LE 4) were selected in the three groups. The dilatational wave (frequency of 2 Hz/10 Hz) was used in the dilatational wave group, the continuous wave (frequency of 10 Hz) was used in the continuous wave group, and the discontinuous wave (frequency of 10 Hz) was used in the discontinuous wave group. All the needles were retained for 30 min. All the treatment was given 3 times a week (on Monday, Wednesday and Friday) for 4 weeks. Lysholm knees scoring scale (LKSS) was used to evaluate the knee joint function before and after treatment, and the content of transforming growth factor-β1 (TGF-β1) in the joint effusion before and after treatment was determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared before treatment, the total score and each score of LKSS were increased after treatment in the three groups (all <0.05). The improvements of total score, pain score, instability score, swelling score of LKSS in the continuous wave group and the dilatational wave group were superior to those in the discontinuous wave group (all <0.05). The content of TGF-β1 in the joint effusion in each group was increased after treatment (<0.05), and the improvement in dilatational wave group was superior to thoes in the continuous wave group and the discontinuous wave group (all <0.05). CONCLUSION The three different waves of EA could all improve the clinical symptoms of KOA, which may promote cartilage repair by increasing TGF-β1 content. The dilatational wave had the best overall effect, which can be used as a clinical optimal treatment.
Acupuncture Points ; Electroacupuncture ; Humans ; Knee Joint ; Osteoarthritis, Knee ; therapy ; Synovial Fluid ; chemistry ; Transforming Growth Factor beta1 ; analysis ; Treatment Outcome

Joint contracture is one of the common musculoskeletal disorders. It has seriously disturbed patients' activities of daily living in various aspects. The pathogenesis of it is eager to explore to distinct degree. Nowadays the thickeness and fibrosis of joint capsular is redarded as the major reason to joint contracture. It is reported that excessive fibroblasts and myofibroblasts activity, collagen hyperplasia, and extracellular matrix (ECM) deposition in these fibrotic condtions lead to the contracture. In addition, upregulators of myofibroblast and collagen synthesis, transforming growth factor-beta 1 (TGF-β1), and connective tissue growth factor (CTGF) were shown to be increased. Altered levels of cytokines were also thought to play a role in this process as elevated levelsof tumor necrosis factor-α(TNF-α), matrix metalloproteinases(MMPs) and abnormal distribution tissue inhibitors of MMPs(TIMPs) were demonstrated in contracted capsules. At present, the methods for clinical treatment of joint contracture mainly include two major categories:stretching therapy, physical factor therapy, exercise therapy, botulinum toxin injection and other non-surgical treatments, arthroscopic lysis, open lysis, and other surgical treatments. Surgical treatment is performed when non-surgical treatment is difficult to achieve further improvement. It has a good effect on mild to moderate joint contracture, but it is difficult to completely restore joint activity for serious joint contracture. Although clinical treatment methods are diverse, the clinical effects are staggered and the effectiveness of their treatment is controversial. Joint contracture is an important challenge faced by orthopedics and rehabilitation physicians, therapists and patients. The review summarized the pathogenesisand treatment of joint contracture and provided a theoretical basis for clinical diagnosis and treatment.
Activities of Daily Living ; Contracture ; Fibroblasts ; Fibrosis ; Humans ; Joint Capsule ; Transforming Growth Factor beta1