Effects of ankylosing spondylitis on cardiovascular disease: aMendelian randomization study.

Objective: Accumulating evidence suggests that patients with ankylosing spondylitis (AS) have an elevated risk for cardiovascular disease (CVD) and cardiovascular death, however, whether AS has causal effects on the risk of CVD is unclear.Two-sample Mendelian randomization (MR) was utilizedto examine the probable causal link between them. Methods: Summary statistics from publicly released genome-wide association studies (GWAS) was used to perform MR analyses. Genetically predicted AS was selected as the exposure variable from published GWAS meta-analyses. CVD was adopted as the outcome variable. The inverse variant weighted method was employed to obtain the casual estimates. The robustness of the results was also examined by evaluating the pleiotropy and heterogeneity of single-nucleotide polymorphisms. Results: According to MR analyses, genetic susceptibility to AS was associated with a high risk of heart failure and ischemic stroke, while negativelygenetic susceptibility was found between AS and peripheral atherosclerosis. No statistical relationship was found between AS and venous thromboembolism, atrial fibrillation, coronary atherosclerosis, and valvular heart disease. Sensitivity analysis showed no evidence of horizontal pleiotropy or heterogeneity. Conclusion: The present study suggests that AS exerts causal effects on the risk of CVD, including heart failure, ischemic stroke, and peripheral atherosclerosis.

Identification of hub genes and transcription factors in patients with primary gout complicated with atherosclerosis.

Evidence shows that primary gout is prone to develop to atherosclerosis, but the mechanism of its occurrence is still not fully clarified. The aim of this study was to explore the molecular mechanism of the occurrence of this complication in gout. The gene expression profiles of primary gout and atherosclerosis were downloaded from the gene expression omnibus database. Overlapping differentially expressed genes (DEGs) between gout and atherosclerosis were identified. The biological roles of common DEGs were explored through enrichment analyses. Hub genes were identified using protein-protein interaction networks. The immune infiltrations of 28 types of immune cells in gout and control samples from GSE160170 were evaluated by the ssGSEA method. Transcription factors (TFs) were predicted using Transcriptional Regulatory Relationships Unraveled by Sentence Based Text Mining (TRRUST) database. A total of 168 overlapping DEGs were identified. Functional enrichment analyses indicated that DEGs were mostly enriched in chemokine signaling pathway, regulation of actin cytoskeleton, and TNF signaling pathway. CytoScape demonstrated 11 hub genes and two gene cluster modules. The immune infiltration analysis showed that the expression of DEGs in gout was significantly upregulated in activated CD4 T cells, gamma delta T cells, T follicular helper cell, CD56dim natural killer cells, and eosinophil. TRRUST predicted one TF, RUNX family transcription factor 1. Our study explored the pathogenesis of gout with atherosclerosis and discovered the immune infiltration of gout. These results may guide future experimental research and clinical transformation.

TLR9 regulates the autophagy-lysosome pathway to promote dendritic cell maturation and activation by activating the TRAF6-cGAS-STING pathway.

Dysregulated maturation and activation of dendritic cells (DCs) play a significant role in the progression of systemic lupus erythematosus (SLE). The autophagy-lysosome pathway has been identified as a potential mechanism to inhibit DC activation and maturation, but its precise workings remain unclear. We investigated the role and regulatory mechanism of TLR9 in modulating the autophagy-lysosome pathway and DCs activation. The mRNA and protein expressions were assessed using qRT-PCR and/or western blot. NZBW/F1 mice was used to construct a lupus nephritis (LN) model in vivo. Cell apoptosis was analyzed by TUNEL staining. Flow cytometry was adopted to analyze DCs surface markers. Lyso-tracker red staining was employed to analyze lysosome acidification. Levels of anti-dsDNA, cytokines, C3, C4, urine protein and urine creatinine were examined by ELISA. The results showed that TLR9 was markedly increased in SLE patients, and its expression was positively correlated with SLEDAI scores and dsDNA level. Conversely, TLR9 expression showed a negative correlation with C3 and C4 levels. Loss-of function experiments demonstrated that TLR9 depletion exerted a substantial inhibition of renal injury, inflammation, and DCs numbers. Additionally, upregulation of TLR9 promoted DCs maturation and activation through activation of autophagy and lysosome acidification. Further investigation revealed that TLR9 targeted TRAF6 to activate the cGAS-STING pathway. Rescue experiments revealed that inactivation of the cGAS/STING signaling pathway could reverse the promoting effects of TLR9 upregulation on DCs maturation, activation, and autophagy-lysosome pathway. Overall, our findings suggested that TLR9 activated the autophagy-lysosome pathway to promote DCs maturation and activation by activating TRAF6-cGAS-STING pathway, thereby promoting SLE progression.

Interaction between rheumatoid arthritis and mediterranean diet on the risk of cardiovascular disease for the middle aged and elderly from National Health and Nutrition Examination Survey (NHANES).

BACKGROUND: Cardiovascular diseases (CVD) occurrence were associated with rheumatoid arthritis (RA) and Mediterranean diet (MD), but few studies have been conducted to explore the combined effect. This study was to outline the relationship of coexistence of RA and MD on the risk of CVD based on the National Health and Nutrition Examination Survey (NHANES) database. METHODS: The data of this cross-sectional study was from the NHANES 2005-2010. The definition of CVD and RA was based on the self-reported questions, respectively; and the alternate MD Index assessed all participants' adherence to the MD. Weighted multivariate logistic regression was adopted to explore the relationship of RA, MD on the risk of CVD, and coexistence effect of RA and MD. The additive interaction was evaluated by the relative excess risk due to interaction (RERI), attributable proportion (AP) and the synergy index (SI). The multiplicative interaction was evaluated by odds ratio (OR) and 95% confidence interval (CI) of product-term. RESULTS: A total of 3,352 participants from NHANES database who were divided into CVD group (n = 385) and non-CVD group (n = 2,967). The result indicated that RA (Model 1: OR = 3.98, 95%CI: 2.76-5.73; Model 2: OR = 2.65, 95%CI: 1.69-4.16) and low adherence to the MD (Model 1: OR = 1.82, 95%CI: 1.13-2.93; Model 2: OR = 1.67, 95%CI:1.01-2.77) was associated with an increased risk of CVD, respectively. Additionally, we observed the additive (RERI = 4.76, 95% CI: 0.52-9.00; AP = 0.74, 95% CI: 0.54-0.95; SI = 8.21, 95% CI: 1.48-45.51) and multiplicative (OR = 3.63, 95% CI: 1.44-9.15) interaction of RA and low adherence to the MD on the risk of CVD. CONCLUSION: RA and MD were associated with CVD occurrence, respectively, and there may be an interaction between RA and MD for the development of CVD.

SIRT1 is transcriptionally repressed by YY1 and suppresses ferroptosis in rheumatoid arthritis.

BACKGROUND: Sirtuin 1 (SIRT1) is reported downregulated in rheumatoid arthritis (RA), and the protective effects of SIRT1 on tissue damage and organ failure may be related to cellular ferroptosis. However, the exact mechanism by which SIRT1 regulates RA remains unclear. METHODS: Quantitative real-time PCR (qPCR) and western blot assays were performed to explore the expressions of SIRT1 and Yin Yang 1 (YY1). CCK-8 assay was used for cytoactive detection. The interaction between SIRT1 and YY1 was validated by dual-luciferase reporter gene assay and chromatin immunoprecipitation (ChIP). DCFH-DA assay and iron assay were applied to detect the reactive oxygen species (ROS) and iron ion levels. RESULTS: In the serum of RA patients, SIRT1 was downregulated, but YY1 was upregulated. In LPS-induced synoviocytes, SIRT1 could increase cell viability and decrease ROS and iron levels. Mechanistically, YY1 downregulated the expression of SIRT1 by inhibiting its transcription. YY1 overexpression partly revised the effects of SIRT1 on ferroptosis in synoviocytes. CONCLUSION: SIRT1 is transcriptionally repressed by YY1 and inhibits the ferroptosis of synoviocytes induced by LPS, so as to relieve the pathological process of RA. Therefore, SIRT1 might be a new diagnosis and therapeutic target of RA.

Downregulation of Sox8 mediates monosodium urate crystal-induced autophagic impairment of cartilage in gout arthritis.

The deposition of monosodium urate (MSU) crystals in arthritic joints of gout seriously damages cartilage. This study aimed to investigate whether MSU crystal-induced cartilage impairment was related to autophagic signaling. mRNAs of cartilage from MSU-induced gouty arthritis rat model were sequenced. MSU crystal-treated human chondrocytes were used to evaluate the function of Sox8. The recombinant Sox8 lentiviral vector (lenti-Sox8) was applied to upregulate the expression of Sox8. Transfection of the mRFP-GFP-LC3 plasmid was evaluated by confocal microscopy. The autophagic vacuoles were stained with monodansylcadaverine and examined by flow cytometry. The morphology of autophagosomes was observed by transmission electron microscopy. The ratio of LC3-II/I in the presence or absence of bafilomycin A1 and the expression levels of Beclin1, Sox8, p-PI3K, PI3K, p-AKT, AKT, p-mTOR, and mTOR were detected by Western blot. In vivo, the effect of Sox8 on cartilage of acute gouty model rats was evaluated by safranin-O/fast green staining and Western blot. The expression of Sox8 was significantly downregulated both in vivo and in vitro. In chondrocytes, MSU crystals reduced the expression of Sox8, inhibited the PI3K/AKT/mTOR signaling pathway, and increased the level of autophagy. Overexpression of Sox8 notably inhibited MSU crystal-induced autophagy by rescuing the phosphorylation levels in the PI3K/AKT/mTOR signaling pathway. In vivo, overexpression of Sox8 remarkably alleviated cartilage damage in acute gouty model rats. These results indicate that downregulation of Sox8 plays an important role in MSU-induced chondrocyte autophagy by modulating PI3K/AKT/mTOR signaling, and overexpression of Sox8 may serve as a novel therapy to prevent the impairment of cartilage in gout arthritis.

SIRT1 is transcriptionally repressed by YY1 and suppresses ferroptosis in rheumatoid arthritis

Abstract Background Sirtuin 1 (SIRT1) is reported downregulated in rheumatoid arthritis (RA), and the protective effects of SIRT1 on tissue damage and organ failure may be related to cellular ferroptosis. However, the exact mechanism by which SIRT1 regulates RA remains unclear. Methods Quantitative real-time PCR (qPCR) and western blot assays were performed to explore the expressions of SIRT1 and Yin Yang 1 (YY1). CCK-8 assay was used for cytoactive detection. The interaction between SIRT1 and YY1 was validated by dual-luciferase reporter gene assay and chromatin immunoprecipitation (ChIP). DCFH-DA assay and iron assay were applied to detect the reactive oxygen species (ROS) and iron ion levels. Results In the serum of RA patients, SIRT1 was downregulated, but YY1 was upregulated. In LPS-induced synoviocytes, SIRT1 could increase cell viability and decrease ROS and iron levels. Mechanistically, YY1 downregulated the expression of SIRT1 by inhibiting its transcription. YY1 overexpression partly revised the effects of SIRT1 on ferroptosis in synoviocytes. Conclusion SIRT1 is transcriptionally repressed by YY1 and inhibits the ferroptosis of synoviocytes induced by LPS, so as to relieve the pathological process of RA. Therefore, SIRT1 might be a new diagnosis and therapeutic target of RA. Highlights Combining SIRT1 with synoviocytes ferroptosis in rheumatoid arthritis for the first time. The transcription factor YY1 combined to the SIRT1 promoter in synovial cells and inhibited its expression and functional roles. The inhibition of SIRT1 with YY1 decreased the ferroptosis in synoviocytes.

Potential biomarkers for active renal involvement in systemic lupus erythematosus patients.

Objective: This study aimed to identify the key genes related to active renal involvement in patients with systemic lupus erythematosus (SLE). Methods: Microarray datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between SLE patients with active renal involvement and those who did not have active renal involvement were identified by R software. Hub genes were identified using protein-protein interaction networks. The relationships between the expression levels of identified hub genes and SLEDAI were subjected to linear correlation analysis. The diagnostic accuracy of the hub genes was evaluated with the area under the curve of the receiver operating characteristic curve (ROC-AUC). Transcription factors (TFs) were predicted. The expression levels of different hub genes and histopathological patterns were also examined. Results: A total of 182 DEGs were identified. Enrichment analysis indicated that DEGs were primarily enriched in neutrophil degranulation, neutrophil activation involved in immune response and neutrophil activation. The expression levels of 12 identified hub genes were verified. Ten of the 12 hub genes were positively associated with SLEDAI. The combination model of DEFA4, CTSG, RETN, CEACAM8, TOP2A, LTF, MPO, ELANE, BIRC5, and LCN2 had a certain diagnostic accuracy in detecting renal involvement with high disease activity in SLE patients. The expressions of five predicted TFs were validated by GSE65391 dataset. Conclusion: This work explored the pathogenesis of renal involvement in SLE. These results may guide future experimental research and clinical transformation.

One of the active ingredients in Paeoniae Radix Alba functions as JAK1 inhibitor in rheumatoid arthritis.

Objective: We aimed to explore and verify the mechanism underlying the action of the active ingredients of Paeoniae Radix Alba (PRA) in the treatment of rheumatoid arthritis (RA). Methods: The protein targets of PRA's six active ingredients and RA were identified. Then, the intersection of the two groups was studied. The drug-target network was constructed, visualized, and analyzed by Cytoscape software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were performed to analyze these genes. Furthermore, we validated our predictions of the potential targets through a docking study. Finally, the anti-inflammatory effect of Palbinone (PB), one of the active ingredients of PRA, was tested by conducting in vitro and in vivo studies. Results: Six active ingredients of PRA were identified, and 103 overlapping genes were discovered. Functional enrichment analysis indicated that the genes are mostly enriched in IL-17 signaling pathway, Th17 cell differentiation, and the FoxO, ErbB, and TNF signaling pathways. 10 hub genes and two gene cluster modules were identified by Cytoscape. Molecular docking analysis proved that PB was able to bind to the ATP binding site of Janus kinase (JAK)1, thereby acting as a potential inhibitor of JAK1. In vitro and in vivo studies demonstrated that PB exerts its anti-inflammatory role via the inhibition of JAK1. Conclusion: We constructed a multitarget pharmacological network of PRA in RA treatment. PB, one of the active compounds of PRA, was demonstrated to be a promising inhibitor of JAK1.

IRF9 and XAF1 as Diagnostic Markers of Primary Sjogren Syndrome.

Objective: Primary Sjogren syndrome (pSS) is characterized by lymphocytic infiltration of the salivary and lacrimal glands. It is a chronic systemic autoimmune disease. Genetic contributions and disturbed biological systems are the two major causes of pSS, but its etiology is unclear. This study is aimed at identifying potential pSS diagnostic markers and mechanisms at the transcriptome level. Methods: Whole blood datasets of patients with pSS were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified using the online tool, GEO2R. R software was used to perform enrichment analyses to understand the functions and enriched pathways of the DEGs. A protein-protein interaction network was constructed to identify hub genes and significant gene clusters. The least absolute shrinkage and selection operator logistic regression was used to screen pSS diagnostic markers. The expression level and diagnostic performance of the identified genes were tested using another GEO dataset. Results: A total of 221 DEGs were screened from the whole blood samples of 161 patients with pSS and 59 healthy controls. Functional enrichment analysis demonstrated that DEGs were mostly enriched in defense response to virus, response to virus, and type I interferon signaling pathway. Cytoscape identified 10 hub genes and two gene clusters. IRF9 (AUC = 0.799) and XAF1 (AUC = 0.792) were identified as pSS diagnostic markers. The expression levels of the two identified genes were validated by GSE51092. Conclusion: IRF9 and XAF1 were identified as diagnostic markers. The potential underlying molecular mechanism of pSS was explored.

Clinical Values of the Identified Hub Genes in Systemic Lupus Erythematosus.

Objective: This study was conducted to identify the biomarkers and mechanisms associated with systemic lupus erythematosus(SLE) at a transcriptome level. Methods: Microarray datasets were downloaded, and differentially expressed genes (DEGs) were identified. Enrichment and protein-protein interaction networks were analyzed, and hub genes were discovered. The levels of top 10 hub genes were validated by another dataset. The diagnostic accuracy of the hub genes was evaluated with the area under the curve of the receiver operating characteristic curve (ROC-AUC). The odds ratios (OR) and 95% confidence intervals (CI) of the relationship between clinical manifestations and hub genes were estimated with multivariable logistic regression. The relationships between the expression levels of the 10 identified hub genes and SLEDAI scores were subjected to linear correlation analysis. Changes in the expression levels of the hub genes during patient follow-up were examined through one-way repeated measures ANOVA. Results: A total of 136 DEGs were identified. Enrichment analysis indicated that DEGs were primarily enriched in type I interferon-associated pathways. The identified hub genes were verified by the GSE65391 dataset. The 10 hub genes had good diagnostic performances. Seven (except IFI6, OAS1 and IFIT3) of the 10 hub genes were positively associated with SLEDAI. The combination models of IFIT3, ISG15, MX2, and IFIH1 were effective in diagnosing mucosal ulcers among patients with SLE. The expression levels of IRF7, IFI35, IFIT3, and ISG15 decreased compared with the baseline expression (not significantly). Conclusions: In this work, the clinical values of the identified hub genes in SLE were demonstrated.

Identification of hub genes and transcription factors in patients with rheumatoid arthritis complicated with atherosclerosis.

The aim of this study was to explore the overlapping key genes, pathway networks and transcription factors (TFs) related to the pathogenesis of rheumatoid arthritis (RA) and atherosclerosis. The gene expression profiles of RA and atherosclerosis were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) between RA and atherosclerosis were identified. The biological roles of common DEGs were explored through enrichment analysis. Hub genes were identified using protein-protein interaction networks. TFs were predicted using Transcriptional Regulatory Relationships Unraveled by Sentence Based Text Mining (TRRUST) database. The hub genes and TFs were validated with other datasets. The networks between TFs and hub genes were constructed by CytoScape software. A total of 131 DEGs (all upregulated) were identified. Functional enrichment analyses indicated that DEGs were mostly enriched in leukocyte migration, neutrophil activation, and phagocytosis. CytoScape demonstrated 12 hub genes and one gene cluster module. Four of the 12 hub genes (CSF1R, CD86, PTPRC, and CD53) were validated by other datasets. TRRUST predicted two TFs, including Spi-1 proto-oncogene (SPI1) and RUNX family transcription factor 1(RUNX1). The expression of RUNX1 was validated with another dataset. Our study explored the common pathogenesis of RA and atherosclerosis. These results may guide future experimental research and clinical transformation.

OX40-Fc Fusion Protein Alleviates PD-1-Fc-Aggravated Rheumatoid Arthritis by Inhibiting Inflammatory Response.

BACKGROUND: Researches have confirmed that the abnormal signals of OX40 and PD-1 lead to the changes of T cell biological behavior, thus participating the immunopathological process of RA. However, the pathogenesis of RA immunopathological process has not been clarified yet. METHODS: 30 DBA/1 mice were randomly divided into 5 groups (6 mice per group): control group, collagen-induced arthritis (CIA) group, PD-1-Fc/CIA group, OX40-Fc/CIA group, and PD-1-Fc + OX40-Fc/CIA group. The pathological changes in mice joints were observed by H&E staining. The proportion of CD4+ T, CD8+ T, CD28+, and CD19+ cells in peripheral blood mononuclear cells (PBMCs) was detected by flow cytometry. Serum inflammatory factors (CRP, IL-2, IL-4, IL-1ß, INF-γ) and bone metabolism-related genes (CTX-I, TRACP-5b, BALP) were detected by ELISA assay. Western blotting was applied to measure the NF-κB signaling pathway-related protein (p-IKKß, p-IκBα, p50) expression in synovial tissue of mice joint. RESULTS: Compared with the control group, CIA mice showed significant increases in arthritis score and pathological score. In the CIA group, a marked decrease was identified in the proportion of CD8+ T, CD19+, and CD68+ cells. Additionally, the CIA group was associated with upregulation of secretion of inflammatory factors in serum and expression of bone metabolism-related genes and NF-κB pathway-related proteins. Compared with the CIA group, the same indexes above showed a further aggravation in the PD-1-Fc group while all indexes improved in the OX40-Fc group. Besides, OX40-Fc fusion protein slowed down significantly the further deterioration of CIA mouse pathological process caused by PD-1-Fc fusion protein. CONCLUSION: OX40-Fc fusion protein alleviates PD-1-Fc-aggravated RA by inhibiting inflammatory response. This research provides biological markers with clinical significance for diagnosis and prognosis of RA, as well as offers theoretical and experimental foundation to the new targets for immune intervention.

Circ_0001947 promotes cell proliferation, invasion, migration and inflammation and inhibits apoptosis in human rheumatoid arthritis fibroblast-like synoviocytes through miR-671-5p/STAT3 axis.

BACKGROUND: Circular RNAs (circRNAs) have emerged as vital regulators in the development of rheumatoid arthritis (RA). In this study, we aimed to explore the functions and mechanisms of circ_0001947 in RA. METHODS: The expression of circ_0001947, microRNA-671-5p (miR-671-5p) and signal transducer and activator of transcription 3 (STAT3) was determined by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell Counting Kit-8 (CCK-8) assay, 5'-ethynyl-2'-deoxyuridine (EdU) assay, flow cytometry analysis, transwell assay and wound-healing assay were performed to assess cell proliferation, apoptosis, invasion and migration. The concentrations of inflammatory factors were examined with enzyme-linked immunosorbent assay (ELISA) kits. Dual-luciferase reporter assay was used to analyze the relationships of circ_0001947, miR-671-5p and STAT3. RESULTS: Circ_0001947 was upregulated in RA patients and RA-FLSs. Knockdown of circ_0001947 repressed cell proliferation, invasion, migration and inflammatory response and facilitated apoptosis in RA-FLSs. Circ_0001947 served as the sponge for miR-671-5p and the inhibitory effect of circ_0001947 in RA-FLS progression was reversed by miR-671-5p inhibition. STAT3 was the target gene of miR-671-5p. MiR-671-5p overexpression restrained RA-FLS growth, invasion, migration and inflammation and promoted apoptosis, but STAT3 upregulation reversed the impacts. CONCLUSION: Circ_0001947 contributed to the progression of RA-FLSs by elevating STAT3 through adsorbing miR-671-5p.

Ten genes are considered as potential biomarkers for the diagnosis of dermatomyositis.

OBJECTIVE: This study aimed to identify the biomarkers and mechanisms for dermatomyositis (DM) progression at the transcriptome level through a combination of microarray and bioinformatic analyses. METHOD: Microarray datasets for skeletal muscle of DM and healthy control (HC) were downloaded from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were identified by using GEO2R. Enrichment analyses were performed to understand the functions and enriched pathways of DEGs. A protein-protein interaction network was constructed to identify hub genes. The top 10 hub genes were validated by other GEO datasets. The diagnostic accuracy of the top 10 hub genes for DM was evaluated using the area under the curve of the receiver operating characteristic curve. RESULT: A total of 63 DEGs were identified between 10 DM samples and 9 HC samples. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that DEGs are mostly enriched in response to virus, defense response to virus, and type I interferon signaling pathway. 10 hub genes and 3 gene cluster modules were identified by Cytoscape. The identified hub genes were verified by GSE1551 and GSE11971 datasets and proven to be potential biomarkers for the diagnosis of DM. CONCLUSION: Our work identified 10 valuable genes as potential biomarkers for the diagnosis of DM and explored the potential underlying molecular mechanism of the disease.

LncRNA GAS5 alleviates rheumatoid arthritis through regulating miR-222-3p/Sirt1 signalling axis.

INTRODUCTION: Rheumatoid arthritis (RA) is an autoimmune disease that affects millions of people. Fibroblast-like synoviocytes (FLSs) located in rheumatoid panni play a pivotal role in the formation of RA. The long noncoding RNA (lncRNA) GAS5 is reportedly downregulated in rheumatoid arthritis. However, its detailed mechanism in RA remains to be explored. This study investigated the roles and related mechanisms of GAS5 in RA. METHODS: The expression levels of GAS5, miR-222-3p, and sirtuin 1 (Sirt1) were evaluated by quantitative PCR (qPCR). Cell proliferation was analyzed by CCK-8 and BrdU assays. Cell apoptosis was assessed by flow cytometry and western blotting. Enzyme-linked immunosorbent assay (ELISA) was utilized to evaluate the levels of TNF-α, IL-1ß, and IL-6. The interaction between GAS5 or Sirt1 and miR-222-3p was predicted by starBase and validated by dual-luciferase reporter assay. RESULTS: GAS5 expression was found to be downregulated in the serum samples of RA patients and in RA-FLSs. GAS5 overexpression or the inhibition of miR-222-3p impeded the activity of RA-FLSs by repressing their proliferation and inflammation and by promoting apoptosis. Mechanistically, GAS5 indirectly regulates Sirt1 expression by binding miR-222-3p. Further experiments confirmed that Sirt1 overexpression restored the anti-RA activity of GAS5 under miR-222-3p mimic. CONCLUSIONS: The miR-222-3p/Sirt1 axis was found to be critical for the function of GAS5 in regulating the proliferation, inflammation, and apoptosis of RA-FLSs. These data indicate GAS5 activation as a potential therapeutic strategy for RA progression.

Immune Function and Mechanism of Costimulating Molecules PD-1 and OX40 in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a T lymphocyte-mediated autoimmune disease, although its immune mechanism has not been fully studied. In this study, healthy controls (HC), osteoarthritis patients (OA), and RA patients were enrolled, and mice were evenly divided into control, collagen-induced arthritis (CIA), PD-1 Fc/CIA (PD-1 Fc membrane fusion protein administered to CIA mice), OX40 Fc/CIA (OX40 Fc membrane fusion protein administered to CIA mice), and PD-1 Fc + OX40 Fc/CIA groups. The expressions of programmed death-1 (PD-1) and OX40 in CD4+ T lymphocytes and the levels of sPD-1, immunoglobulin, and proinflammatory factors in patients and mice were measured. The results showed that the expression levels of PD-1 and OX40 in CD4+ T lymphocytes separated from the peripheral blood and synovial fluid of RA patients and the spleen of CIA mice were observably elevated. The levels of soluble PD-1, interleukin (IL)-2, IL-4, IL-5, IL-17, and interferon-γ (IFN-γ) in RA patients obviously increased. In animal experiments, PD-1 Fc not only increased the serum levels of immunoglobulin G (IgG), IgG1, and IgG2a in CIA mice, but also increased the levels of IL-4, IL-2, IL-5, IL-17, and IFN-γ in mouse spleen cells and joint tissues, which, however, were reversed by OX40 Fc. In conclusion, OX40 inhibition could reverse the progression of RA caused by PD-1 blocking, and PD-1 might be a potential target for RA. Clinical Trials.gov ID: HGH2018012203.

The association between serum uric acid level and changes of MRI findings in knee osteoarthritis: A retrospective study (A STROBE-compliant article).

The objective of this study was to examine whether Magnetic resonance imaging (MRI) features of knee osteoarthritis (OA) had an association with the level of serum uric acid (SUA). The MRI of the OA patients from June 2015 to July 2017 were studied. The patients fulfilled the following inclusion criteria: 1) meet American College of Rheumatology (ACR) radiological and clinical criteria for OA of the knee, 2) age ≤ 65years old, 3) Body mass index (BMI) < 25 kg/m. Patients with OA were categorized into two groups based on the level of SUA. Patients with SUA level lower than 360 umol/L were recruited into the first group and the others were the second group. Odds ratios (OR) and 95% confidence intervals (CI) for SUA level and different MRI patterns were estimated with multivariable logistic regression.71 patients were included in this research. The mean age of the first group was 54.5 ±â€Š8.4 and the second group was 55.6 ±â€Š6.4. The Body Mass Index (BMI) of two groups was 22.7 ±â€Š1.3 and 23.23 ±â€Š1.9 separately. The mean SUA and creatinine (CR) level of the second group were 433.8 ±â€Š70.6 umol/L and 80.1 ±â€Š23.9 umol/L. There were statistically more focal erosions, osteophytes, bone marrow lesions and synovitis in the MRIs of the second group. A positive association between SUA level and synovitis as well as soft tissue swelling in MRIs was observed in patients with knee OA (OR = 1.017; 1.008, 95% CI: 1.007-1.028; 1.000-1.016). In conclusion, subjects with higher SUA level were more likely to have MRI abnormalities. OA patients need to lower their SUA level in order to keep the disease from progressing.

Toll-like receptor-9 is involved in the development of B cell stimulating factor-induced systemic lupus erythematosus.

The objective of the present study was to investigate the role of Toll-like receptor (TLR)-9 in B lymphocyte stimulating factor (BLyS)-induced systemic lupus erythematosus (SLE) in mice. The anti-double stranded (ds)DNA antibody titer, levels of complement proteins (C3 and C4), interleukin (IL)-10 and the disease activity [assessed by the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level] were measured. A total of 21 transgenic female mice (aged 8-10 weeks and weighing 30-40 g) expressing the Epstein-Barr virus membrane antigen, BLLF1, were studied. Mice were randomly divided into the control, the BLyS inhibition and the TLR-9 inhibition groups, with 7 mice in each group. Mice in the blank control group received intraperitoneal injections of normal saline, mice in the BLyS inhibition group received intraperitoneal injections of anti-BR3 monoclonal antibody (5,000 ng/day) and mice in the TLR-9 inhibition group received intraperitoneal injections of anti-human TLR-9 antibody (250 ng/day). The treatment regimens continued for 10 days, followed by the collection of peripheral venous blood. The relative levels of TLR-9 mRNA were measured by reverse transcription-quantitative polymerase chain reaction. Furthermore, the BLyS protein concentration and IL-10 levels were measured by ELISA. TLR-9 mRNA, BLyS, IL-10, anti-dsDNA antibody titer, C3, C4, ESR and CRP levels of the blank control group were significantly higher than those of the other two groups (P<0.05). The differences in comparison of these indexes between the BLyS inhibition and TLR-9 inhibition groups were not statistically significant (P>0.05), with the exception of TLR-9 mRNA and BLyS. In conclusion, the TLR-9 signaling pathway may be important for BLyS-induced SLE, and regulation of the inflammatory immune level.

[Fosinopril up-regulates and ameliorates the Ang II induced down-expression of klotho gene in NRK-52E].

OBJECTIVE: To investigate the effect of fosinopril (Fos) on regulating klotho gene expression and elucidate the mechanism of Fos regulating the Angiotensin II (AngII) -induced down-expression of klotho gene. METHODS: Culture cells, NRK-52E, were incubated with media either AngII or Fos or both of all. Experimental groups incubated with Fos (10(-5) mol/L) were divided according to variant points of time for 0 (control), 3, 6, 12, 24 h. Different concentration of Fos was selected to incubated with culture cells for 0 (control), 10(-9) 10(-8), 10(-7), 10(-6), 10(-5) mol/L at the optimal time point (24 h). Five groups, which were A: control; B: AngII (10(-7) mol/L); C: Fos(10(-5) mol/L); D: AngII (10(-7) mol/L) + Fos(10(-5) mol/L) and E: Cells pretreated with Fos(10(-5) mol/L)12 h incubated with AngII (10(-7) mol/L) were divided to observe the effect of Fos on expression of klotho induced by AngII. RT-PCR and immunohistochemistry (IHC) were applied to evaluate the klotho mRNA and protein expression, respectively. RESULTS: Fos up-regulated klotho mRNA in time-dependent manner, and independent of dose-dependent manner; AngII obviously decreased the levels of kloltho mRNA and protein expression in NRK-52E as compared to the control (P < 0.05), the down-regulating effect was reversed by incubating both with AngII and Fos (P < 0.05), and Fos could inhibit the down-regulated expression of klotho gene induced by Ang II in NRK-52E. CONCLUSION: Fosinopril up-regulates klotho mRNA in time-dependent manner, and inhibits the down-regulated expression of klotho gene induced by Ang II.