Synovium and blood capillaries at the femoral attachment of anterior cruciate ligament are significantly abundant than those at the tibial attachment / Sinovial y capilares sanguíneos en la inserción femoral del ligamento cruzado anterior son significativamente más abundantes que los de la inserción tibial

SUMMARY: The anterior cruciate ligament (ACL) is a ligament that mainly controls the anterior and rotational mobility of the knee joint, and its surface is covered by a synovial membrane with large number of blood vessels. In general, nutritional supply to the ligament is from many capillaries in the adjacent synovium. However, statistical studies of the capillaries distributed to the ACL are insufficient. In this study, we examined cross-sectional histological images of the femoral attachment (femoral level), middle level of the tendon (middle level), and tibial attachment (tibial level) of the ACL and statistically analyzed blood capillary distribution among the three levels. The ACLs of 10 cadavers were divided into 5 equal sections, and 4mm-thick paraffin sections were made at the femoral level, middle level, and tibial level, and then hematoxylin-eosin (HE) staining were performed. The area of each transverse section was measured using Image-J 1.51n (U. S. National Institutes of Health, Bethesda, MD, USA). Fiber bundles of the ACL were relatively small and sparse in cross-sectional area at the femoral level and became larger and denser toward the tibial level. Many blood levels. The synovium at the attachment of ACL covered the surface of the fiber bundle and also penetrated deeply between the fiber bundles. In particular, the blood capillaries were densely distributed in the synovium at the femoral attachment rather than another two levels. Indeed, the number of capillaries were also most abundant in the femoral level. The cross-sectional ACL area at the femoral level is significantly small, however, the blood capillaries were most abundant. Therefore, when the ACL is injured, its reconstruction with preservation of the femoral ligamentous remnant may be clinically useful for remodeling of the grafted tendon.

El ligamento cruzado anterior (LCA) es un ligamento que controla principalmente la movilidad anterior y rotacional de la articulación de la rodilla, y su superficie está cubierta por una membrana sinovial con gran cantidad de vasos sanguíneos. En general, el suministro de nutrientes al ligamento proviene de muchos capilares en la sinovial adyacente. Sin embargo, los estudios estadísticos de los capilares distribuidos en el LCA son insuficientes. En este estudio, examinamos imágenes histológicas trans- versales de la inserción femoral (nivel femoral), el nivel medio del tendón (nivel medio) y la inserción tibial (nivel tibial) del LCA y analizamos estadísticamente la distribución de los capilares sanguíneos entre los tres niveles. Los LCA de 10 cadáveres se dividieron en 5 secciones iguales y se realizaron cortes en parafina de 4 µm de espesor a nivel femoral, medio y tibial, y luego se realizó tinción con hematoxilina-eosina (HE). El área de cada sección transversal se midió utilizando Image-J 1.51n (Institutos Nacionales de Salud de EE. UU., Bethesda, MD, EE. UU.). Los haces de fibras del LCA eran relativamente pequeños y escasos en el área de la sección transversal a nivel femoral y se hicieron más grandes y más densos hacia el nivel tibial. La membrana sinovial en la unión del LCA cubría la superficie del haz de fibras y también penetraba profundamente entre entre los haces de fibras. En particular, los capilares sanguíneos estaban densamente distribuidos en la unión femoral de la sinovial respecto a los otros dos niveles. De hecho, el número de capilares también fue más abundante a nivel femoral. El área transversal del LCA a nivel femoral era significativamente pequeña, sin embargo, los capilares sanguíneos fueron los más abundantes. Por lo tanto, cuando hay una lesión del LCA su reconstrucción con preservación del ligamento femoral remanente puede ser clínicamente útil para remodelar el tendón injertado.

The expression of long non-coding RNA human leukocyte antigen complex P5(lncRNA HCP5) in synovial tissue of patients with rheumatoid arthritis is up-regulated and correlated with immune cell infiltration / 细胞与分子免疫学杂志

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.

Triptolide inhibits inflammatory response and migration of fibroblast like synovial cells in rheumatoid arthritis through the circRNA 0003353/JAK2/STAT3 signaling pathway / 南方医科大学学报

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.

Effect of miR-124a on collagen-induced arthritis in mice and the underlying mechanisms / 中南大学学报(医学版)

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.

Lipoma Arborescente: uma causa de sinovite crônica? / Lipoma Arborescens: a cause of chronic synovitis?

O lipoma arborescente é uma causa incomum de lesão intra-articular que se apresenta como aumento de volume articular indolor, lentamente progressivo, que persiste por muitos anos e é acompanhado por derrames articulares intermitentes. O envolvimento de sítios extra-articulares é incomum, mas pode ocorrer em bainhas tendíneas e bursas. A ressonância magnética é o melhor exame para o diagnóstico, embora a biópsia sinovial possa ser necessária em alguns casos. Relatamos três casos com o objetivo de destacar o espectro clínico da doença, as características da imagem e a resposta ao tratamento imunossupressor.

Lipoma arborescens is an uncommon cause of intra-articular masses that presents as slowly progressive painless swelling of the joint, which persists for many years and is accompanied by intermittent effusions. Extra-articular site(s) involvement is unusual, but can occur in tendon sheaths and bursas. Magnetic resonance imaging is the best diagnostic exam, although synovial biopsy may be necessary. We report three cases in order to highlight the clinical spectrum and imaging features of the disease, so that early diagnosis and appropriate treatment can be given.

Effect of Xinfeng Capsules-containing serum on TNF-α-induced apoptosis and inflammation of fibroblast-like synoviocytes in rheumatoid arthritis / 中国中药杂志

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.

Effect of moxibustion on PI3K/Akt/mTOR signaling pathway in foot-pad synovium in rats with rheumatoid arthritis / 中国针灸

OBJECTIVE@#To observe the effect of moxibustion on phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin protein (PI3K/Akt/mTOR) signaling pathway in the foot-pad synovial tissue in rats with rheumatoid arthritis (RA), and to explore the mechanism of moxibustion for treating RA.@*METHODS@#Forty healthy SD rats were randomly divided into a control group, a model group, a moxibustion group, a cigarette-moxibustion group and a medication group, 8 rats in each group. The RA model was established with subcutaneous injection of complete Freund's adjuvant (CFA) in the left hind foot-pad under wind, cold and wet environment in the model group, the moxibustion group, the cigarette-moxibustion group and the medication group. The rats in the moxibustion group were treated with moxibustion at "Zusanli" (ST 36) for 20 min; the rats in the cigarette-moxibustion group were treated with moxibustion of ordinary cigarette at "Zusanli" (ST 36) for 20 min; the rats in the medication group were treated with tripterygium glycosides suspension (0.8 mg/100 g) by gavage. All the intervention was given once a day for 15 days. The left hind foot-pad volume was measured before and after modeling and after 15-day intervention. After 15-day intervention, the serum levels of IL-17 and IL-23 were detected by ELISA method, and the expression levels of PI3K, Akt and mTOR in synovial tissue of left hind foot-pad were detected by Western blot method.@*RESULTS@#The volume of left hind foot-pad, the serum levels of IL-23 and IL-17 and the expression of PI3K, Akt and mTOR in synovial tissue of left hind foot-pad in the model group were higher than those in the control group (@*CONCLUSION@#Moxibustion may play a therapeutic effect on RA by inhibiting the level of IL-23, IL-17 and the activity PI3K/Akt/mTOR, and regulating inflammatory response and autophagy.

Expression of cartilage oligomeric matrix protein in the synovial chondromatosis of the temporomandibular joint / 北京大学学报(医学版)

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.

decoction induces apoptosis by activating Fas/caspase-8 pathway in rheumatoid arthritis fibroblast-like synoviocytes / 南方医科大学学报

OBJECTIVE@#To explore the effect of decoction (DGNTD) on cell apoptosis and TNF receptor super family 6 (Fas)/caspase-8 pathway in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS).@*METHODS@#FLS isolated from the synovial tissue of RA patients were cultured and identified using immunofluorescence staining. The cells were treated with 10% blank serum (blank control group), 10% sera containing low, moderate or high doses of DGNTD, or 20 μmol/mL KR-33493 (a Fas inhibitor) combined with 10% serum containing high-dose DGNTD. MTT assay was used to detect the proliferation of the cells after the treatments. Apoptosis of the cells was detected at 48 h in each group using Hoechst 33342 staining and flow cytometry with annexin V-FITC/PI staining. The mRNA and protein expressions of Fas, FADD, caspase-8 and caspase-3 in the cells at 48 h were detected using qPCR and Western blotting.@*RESULTS@#Immunofluorescence staining identified the cultured cells as FLS. Treatment with DGNTD-containing sera significantly inhibited the proliferation of FLS, and the inhibitory effects were enhanced as the dose and intervention time increased ( < 0.05). Hoechst 33342 staining and flow cytometry showed that the sera containing different doses of DGNTD significantly promoted apoptosis of FLS ( < 0.05). The expression levels of Fas, FADD, caspase-8, and caspase-3 at both mRNA and protein levels were significantly increased in the cells after treatment with different doses of DGNTD-containing sera ( < 0.05). The application of KR-33493 obviously reversed the effects of DGNTD on the FLS ( < 0.05).@*CONCLUSIONS@#DGNTD can induce apoptosis of the FLS by activating Fas/caspase-8 signaling pathway.

Effect of (, TLZT) gel preparation on p53 /miR-502-5p /NF-κBp65 in synovial tissue of knee osteoarthritis / 中国骨伤

OBJECTIVE@#To observe effects of (, TLZT) gel preparation on p53, miR-502-5p, NF-κBp65 in synovial tissue of knee osteoarthritis (KOA), and to explore mechanism of TLZT gel preparation in treating KOA.@*METHODS@#Thirthy-six Wistar rats aged 8 weeks and weighed 200 to 220 g (meaned 208 g) were randomly divided into normal group, model group and traditional Chinese medicine (TCM) group, 12 rats in each group. KOA model was established by modified Hulth method. After 4 weeks of modeling, TCM group treated with TLZT gel preparation for external use, 3 times daily for 2 weeks;normal group and model group were fed normally without intervention. After treatment, morphological changes of specimens in each group were observed, changes of miR-502-5p in synovial tissue were detected by qPCR, and contents of p53, NF-κBp65, IL-1β, TNF-α, MMP-13 in synovial tissue were detected by qPCR and Western Blot respectively.@*RESULTS@#(1)Morphological observation of specimens showed that the articular cartilage in model group was hyaline and uneven, the synovial membranes were hypertrophic and proliferative with a large number of inflammatory cells infiltrating, the joint fluid was thicker in texture;the articular cartilage in TCM group was more transparent and smooth, synovial hyperplasia was mild with a small amount of inflammatory cell infiltration, the texture of articular fluid was clear and sparse. (2) Compared with normal group, content of miR-502-5p of synovial tissue in model and TCM group were increased, mRNA and expression of p53 decreased, expression of NF-κBp65, IL-1β, TNF-α, MMP-13 increased. (3)Compared with model group, content of miR-502-5p in synovial tissue of TCM group decreased (<0.05), mRNA and protein expression of p53 increased (<0.05), mRNA and protein expression of NF-κBp65, IL-1β, TNF-α, MMP-13 decreased (<0.05).@*CONCLUSION@#Expression of p53, miR-502 -5p, NF -κBp65 in synovial tissue is closely related to synovial hyperplasia and inflammatory reaction, TLZT gel preparation may reduce proliferation and inflammatory reaction of KOA synovium by regulating the expression of p53, miR- 502-5p, NF-κBp65 in synovial tissues.

Increased elastic modulus of the synovial membrane in a rat ACLT model of osteoarthritis revealed by atomic force microscopy

This study aimed to explore changes in nanoscale elastic modulus of the synovium using atomic force microscopy (AFM) in addition to investigate changes in synovial histomorphology and secretory function in osteoarthritis (OA) in a rat anterior cruciate ligament transection (ACLT) model. Sprague-Dawley rats were randomly assigned to sham control and ACLT OA groups. All right knee joints were harvested at 4, 8, or 12 weeks (W) after surgery for histological assessment of cartilage damage and synovitis in both the anterior and posterior capsules. AFM imaging and nanoscale biomechanical testing were conducted to measure the elastic modulus of the synovial collagen fibrils. Immunohistochemistry was used to visualize the expression of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and matrix metalloproteinase-3 (MMP-3) in the synovium. The OA groups exhibited progressive development of disease in the cartilage and synovium. Histopathological scores of the synovium in the OA groups increased gradually. Significant differences were observed between all OA groups except for the posterior 4W group. The synovial fibril arrangement in all OA groups was significantly disordered. The synovial fibrils in all ACLT OA groups at each time point were stiffer than those in the sham controls. OA rats displayed a significantly higher expression of IL-1β and MMP3 in the anterior capsule. In summary, synovial stiffening was closely associated with joint degeneration and might be a factor contributing to synovitis and increased production of proinflammatory mediators. Our data provided insights into the role of synovitis, particularly stiffening of the synovium, in OA pathogenesis.

IL-22 increases the production of sFRP3 by FLS in inflammatory joint diseases

Rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) are inflammatory diseases with different bone remodeling patterns. Fibroblast-like synoviocytes (FLS) are cells involved in the transition from an acute and reparable phase to a chronic and persistent stage in these diseases. The distinction of joint phenotypes involves inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-17, and IL-22 directly or through key signaling pathways such as Wnt. To evaluate the role of FLS as the source of Wnt antagonists (sFRP3/FRZB and Dkk1) in the synovia, levels of TNF- α, IL-17, IL-22, Dkk1, and sFRP3 were measured by ELISA directly in the synovial fluid of patients with RA, PsA, or AS. Dkk1 and sFRP3 were also measured in the FLS culture supernatants after different inflammatory stimulus. sFRP3 and Dkk1 are constitutively expressed by FLS. IL-22 and sFRP3 were positively correlated (r=0.76; P<0.01) in synovial fluid. The stimulation of FLS with IL-22, but not TNF-alpha and IL-17, increased the production of sFRP3. No stimulus altered the basal expression of Dkk1. These results showed, for the first time, the ability of IL-22 to increase the expression of sFRP3/FRZB by human FLS in both in vitro and ex vivo models. This finding linked IL-22 to local inhibition of Wnt signaling and possibly to blockade of osteogenesis. Furthermore, FLS presented as a source of this inhibitor in synovial fluid, assigning to this cell a bone injury mechanism.

Surgical Treatment for Diffuse Pigmented Villonodular Synovitis of the Ankle by A Combined Open and Arthroscopic Synovectomy: A Case Report / 대한족부족관절학회지

Pigmented villonodular synovitis (PVNS) is a rare proliferative disease involving the synovial membranes. Complete excision with a total synovectomy is important for diffuse type PVNS because of its high recurrence rate. In the ankle, complete excision of diffuse type PVNS is difficult due to the anatomical structure of the ankle joint. This paper reports the author's experience of surgical treatment with combined open and arthroscopic synovectomy. In this manner, it is expected that the complications of the open procedure and the recurrence rate of arthroscopic procedure can be reduced.

Pigmented Villonodular Synovitis Developing in the Knee of a Rheumatoid Arthritis Patient Mistaken as a Rheumatoid Arthritis Flare-Up / 대한내과학회지

Pigmented villonodular synovitis is a benign tumor arising from synovial fibroblasts or histiocytes. There are diffuse and localized forms: the former involves the entire synovium and the latter consists of nodules, small tumefactions, or pedunculated masses. The knee is the joint most commonly affected and the clinical diagnosis is difficult, so initial misdiagnosis is common. We report a case of pigmented villonodular synovitis developing in the knee of rheumatoid arthritis (RA) patient, mistaken for an RA flare-up.

The Risk of Cardiovascular Disease and Diabetes in Rheumatoid Arthritis Patients: A Propensity Score Analysis

BACKGROUND: Rheumatoid arthritis (RA) is a systemic inflammatory disease that manifests as joint damage or athletic disability via sustained inflammation of the synovial membrane. The risk of cardiovascular disease (CVD) is higher in RA patients. This study aimed at evaluating the association between CVD comorbidities and RA by comparing a pharmacotherapy group with a non-pharmacotherapy group. METHODS: Patient sample data from the Health Insurance Review and Assessment Service (HIRA-NPS-2016) were used. Inverse probability of treatment weighting (IPTW) using the propensity score was used to minimize the differences in patient characteristics. Logistic regression analysis was used to evaluate the risk of CVD comorbidities. RESULTS: The analyses included 1,207,213 patients, of which 33,122 (2.8%) had RA. The odds ratios (OR) of CVD comorbidities were increased in RA patients; ischemic heart disease (IHD: OR 1.75; 95% CI 1.73, 1.77), cerebral infarction (CERI: OR 1.28; 95% CI 1.26, 1.30), hypertension (HTN: OR 1.44; 95% CI 1.43, 1.45), diabetes mellitus (DM: OR 2.04; 95% CI 2.03, 2.06), and dyslipidemia (DL: OR 3.49; 95% CI 3.47, 3.51). The ORs of IHD, CERI, HTN, and DM in the traditional DMARD and biologic treatment groups were decreased, compared with those in the non-pharmacotherapy group. CONCLUSIONS: Thus, CVD risk was higher in RA patients, considering age, sex, and socioeconomic status. Appropriate pharmacotherapy could decrease the risk of CVD comorbidities in RA patients.

Angiopoietin-Like Protein 2 Induces Synovial Inflammation in the Facet Joint Leading to Degenerative Changes via Interleukin-6 Secretion

STUDY DESIGN: Experimental human study. PURPOSE: To determine whether angiopoietin-like protein 2 (ANGPTL2) is highly expressed in the hyperplastic facet joint (FJ) synovium and whether it activates interleukin-6 (IL-6) secretion in FJ synoviocytes. OVERVIEW OF LITERATURE: Mechanical stress-induced synovitis is partially, but significantly, responsible for degenerative and subsequently osteoarthritic changes in the FJ tissues in patients with lumbar spinal stenosis (LSS). However, the underlying molecular mechanism remains unclear. IL-6 is highly expressed in degenerative FJ synovial tissue and is responsible for local chronic inflammation. ANGPTL2, an inflammatory and mechanically induced mediator, promotes the expression of IL-6 in many cells. METHODS: FJ tissues were harvested from five patients who had undergone lumbar surgery. Immunohistochemistry for ANGPTL2, IL-6, and cell markers was performed in the FJ tissue samples. After cultured synoviocytes from the FJ tissues were subjected to mechanical stress, ANGPTL2 expression and secretion were measured quantitatively using real-time quantitative reverse-transcription–polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA), respectively. Following ANGPTL2 administration in the FJ synoviocytes, anti-nuclear factor-κB (NF-κB) activation was investigated using immunocytochemistry, and IL-6 expression and secretion were assayed quantitatively with or without NF-κB inhibitor. Moreover, we assessed whether ANGPTL2-induced IL-6 modulates leucocyte recruitment in the degenerative process by focusing on the monocyte chemoattractant protein-1 (MCP-1) expression. RESULTS: ANGPTL2 and IL-6 were highly expressed in the hyperplastic FJ synovium samples. ANGPTL2 was co-expressed in both, fibroblast-like and macrophage-like synoviocytes. Further, the expression and secretion of ANGPTL2 in the FJ synoviocytes increased in response to stimulation by mechanical stretching. ANGPTL2 protein promoted the nuclear translocation of NF-κB and induced IL-6 expression and secretion in the FJ synoviocytes. This effect was reversed following treatment with NF-κB inhibitor. Furthermore, ANGPTL2-induced IL-6 upregulated the MCP-1 expression in the FJ synoviocytes. CONCLUSIONS: Mechanical stress-induced ANGPTL2 promotes chronic inflammation in the FJ synovium by activating IL-6 secretion, leading to FJ degeneration and subsequent LSS.

Role of TLR4/NF-κB pathway for early change of synovial membrane in knee osteoarthritis rats / 中国骨伤

OBJECTIVE@#To study role of TLR4/NF-κB pathway for early change of synovial membrane in knee osteoarthritis rats.@*METHODS@#Eighteen male SD rats weighted (200±20) g were randomly divided into 2 groups, namely control and model group, and 9 in each group. Knee OA model group was established by using modified Hulth method in model group. Control group was not treated. Synovial tissue and serum was extracted at 4 and 21 d after operation. Expression of CD14, TLR4, IL-1β, TNF-α, ADAMTS-4, MMP-13 were detected by real-time PCR respectively. NF-κB p65 protein was detected by Western-blot; serum concentrations of haluronic acid (HA), N-propeptide of type III procollagen(PIIINP) was detected by Elisa.@*RESULTS@#Expression of CD14, ADAMTS-4, and NF-κB p65 in model group were higher than that of control group at 4 and 21 days after operation, while expression of TLR4, IL-1β, TNF-α and MMP-13 were higher than that of control group at 21 days after operation(<0.01). Concentration of PIIINP and HA in model group were higher than that of control group at 4 days after operation, while there was no significant difference at 21 days after operation.@*CONCLUSIONS@#NF-κB pathway could mediate occurrence of KOA by early activating and triggeringg synovial increasingly secreting inflammatory secretion CD14, TLR4, IL-1β, TNF-α, ADAMTS-4, MMP-13, PIIINP and HA.

High Expression of Multidrug Resistance Gene-1 Can Aggravate Resistance to Methotrexate in Rheumatoid Arthritis Patients / 中国医学科学院学报

Objective To explore the role of multidrug resistance gene-1(MDR1)gene in methotrexate(MTX)resistance in patients with rheumatoid arthritis(RA).Methods Fibroblast-like synoviocytes(FLS)from RA patients were infected with recombinant adenovirus Ad-EGFP-MDR1 to obtain MDR1 over-expressed RA FLS.The transcription level of MDR1 gene and the expression level of its coding product P-glycoprotein(P-gp) rotein were detected by real-time PCR and Western blot analysis.The efflux function was verified by rhodamine 123 efflux assay.The resistance to MTX was detected by MTT assay.Results RA FLS were infected with recombinant adenovirus Ad-EGFP-MDR1;72 hours later,the particles size in MDR1 over-expressed RA FLS increased,the cell volume became larger,and the growth rate decreased.The transcription level of MDR1(1.4325±0.3924 0.0650±0.0070;=6.035,=0.004),the expression level of P-gp protein(1.8667±0.2857 0.9367±0.0551;=5.536,=0.005),and the ability of extracellular rhodamine 123(979.43±196.81 1680.06±147.04;=-4.940,=0.008) in MDR1 over-expressed RA FLS were significantly higher than those of negative virus control RA-FLS,and the survival rate of MDR1 over-expressed RA FLS was significantly increased at each concentration of MTX(<0.05).Conclusion The high expression of MDR1 can affect the efflux ability to MTX by up-regulating the expression of P-gp,thus enhancing the drug resistance to MTX in RA FLS.