Search for: rheumatoid arthritis    methotrexate    autoimmune disease    biomarker    gene expression    GWAS    HLA genes    non-HLA genes   

ID PMID Title PublicationDate abstract
30532219 Development and validation of a prognostic multivariable model to predict insufficient cli 2018 OBJECTIVE: The objective was to predict insufficient response to 3 months methotrexate (MTX) in DMARD naïve rheumatoid arthritis patients. METHODS: A Multivariable logistic regression model of rheumatoid arthritis patients starting MTX was developed in a derivation cohort with 285 patients starting MTX in a clinical multicentre, stratified single-blinded trial, performed in seven secondary care clinics and a tertiary care clinic. The model was validated in a validation cohort with 102 patients starting MTX at a tertiary care clinic. Outcome was insufficient response (disease activity score (DAS)28 >3.2) after 3 months of MTX treatment. Clinical characteristics, lifestyle variables, genetic and metabolic biomarkers were determined at baseline in both cohorts. These variables were dichotomized and used to construct a multivariable prediction model with backward logistic regression analysis. RESULTS: The prediction model for insufficient response in the derivation cohort, included: DAS28>5.1, Health Assessment Questionnaire>0.6, current smoking, BMI>25 kg/m2, ABCB1 rs1045642 genotype, ABCC3 rs4793665 genotype, and erythrocyte-folate<750 nmol/L. In the derivation cohort, AUC of ROC curve was 0.80 (95%CI: 0.73-0.86), and 0.80 (95%CI: 0.69-0.91) in the validation cohort. Betas of the prediction model were transformed into total risk score (range 0-8). At cutoff of ≥4, probability for insufficient response was 44%. Sensitivity was 71%, specificity 72%, with positive and negative predictive value of 72% and 71%. CONCLUSIONS: A prognostics prediction model for insufficient response to MTX in 2 prospective RA cohorts by combining genetic, metabolic, clinical and lifestyle variables was developed and validated. This model satisfactorily identified RA patients with high risk of insufficient response to MTX.
29352842 Amylin in the insulin resistance of patients with rheumatoid arthritis. 2018 May OBJECTIVES: Amylin, which is co-secreted with insulin, plays a role in glycemic regulation and is impaired in type 2 diabetes. In the present study we assess, for the first time, the implication of amylin in the development of insulin resistance (IR) in rheumatoid arthritis (RA). METHODS: This was a cross-sectional study involving 361 non-diabetic individuals, 151 patients with RA and 210 sex-matched controls. Insulin, C-peptide, amylin, lipoprotein serum concentrations, and IR indexes by homeostatic model assessment (HOMA2) were evaluated in patients and controls. A multivariable analysis, adjusted for IR-related factors, was performed to determine the differences between patients and controls vis-à-vis amylin and how it is related to IR in RA. RESULTS: Insulin, C-peptide and HOMA2-IR indexes were higher in RA patients than in controls. Amylin serum levels were found to be upregulated in RA patients compared to controls (1.36 ± 0.81 vs. 1.79 ± 1.51 ng/ml, p=0.011), although this difference was lost after adjusting for covariates (p=0.46). While amylin positively correlated with the presence of rheumatoid factor (beta coef. 0.90 [95%CI -0.23-1.56], p=0.009) and SDAI (beta coef 0.01 [95%CI 0.00-0.03], p=0.034), no significant association with other disease activity scores, glucocorticoid intake, methotrexate use or TNF-alpha inhibitors was found. CONCLUSIONS: IR in RA does not appear to be mediated by amylin. This would imply that the mechanisms associated with IR in RA patients differ from those at work in type 2 diabetes.
29627826 Meibomian Gland Dysfunction in Primary and Secondary Sjögren Syndrome. 2018 PURPOSE: We hypothesized that women with primary (pSS) and secondary Sjögren syndrome (sSS; with systemic lupus erythematosus [SLE] or rheumatoid arthritis [RA]) have meibomian gland dysfunction (MGD). We sought to test our hypothesis. METHODS: Subjects with pSS, sSS + SLE, sSS + RA, and non-SS-related MGD were recruited from the Sjögren's Syndrome Foundation or outpatient clinics at Tufts University School of Dental Medicine or Brigham and Women's Hospital. The control population was recruited from the Greater Boston area. After providing written informed consent, the subjects underwent an eye examination and/or completed two questionnaires that assess symptoms of dry eye disease (DED). RESULTS: Our results demonstrate that pSS and sSS patients have MGD. These subjects had meibomian gland orifice metaplasia, an increased number of occluded meibomian gland orifices, and a reduced quality of meibomian gland secretions. Further, patients with pSS, sSS + SLE, sSS + RA, and MGD had significant alterations in their tear film, lid margin, cornea, and conjunctiva. Symptoms of DED were increased ∼10-fold in all pSS, sSS, and MGD groups relative to controls. CONCLUSIONS: Our findings support our hypothesis and show that individuals with pSS, sSS + SLE, and sSS + RA have MGD. In addition, our study indicates that patients with pSS and sSS have both aqueous-deficient and evaporative DED.
29678503 Caffeine inhibits STAT1 signaling and downregulates inflammatory pathways involved in auto 2018 Jul Caffeine is a widely consumed pharmacologically active product. We focused on characterizing immunomodulatory effects of caffeine on peripheral blood mononuclear cells. Caffeine at high doses showed a robust downregulatory effect on cytokine activity and genes related to several autoimmune diseases including lupus and rheumatoid arthritis. Dose-dependent validation experiments showed downregulation at the mRNA levels of key inflammation-related genes including STAT1, TNF, IFNG, and PPARG. TNF and PPARG were suppressed even with the lowest caffeine dose tested, which corresponds to the serum concentration of caffeine after administration of one cup of coffee. Cytokine levels of IL-8, MIP-1β, IL-6, IFN-γ, GM-CSF, TNF, IL-2, IL-4, MCP-1, and IL-10 were decreased significantly with caffeine treatment. Upstream regulator analysis suggests that caffeine inhibits STAT1 signaling, which was confirmed by showing reduced phosphorylated STAT1 after caffeine treatment. Further studies exploring disease-modulating potential of caffeine in autoimmune diseases and further exploring the mechanisms involved are warranted.
30071881 BATF regulates collagen-induced arthritis by regulating T helper cell differentiation. 2018 Aug 2 BACKGROUND: We recently demonstrated that BATF, a member of the activator protein-1 (AP-1) family, regulates osteoarthritic cartilage destruction. Here, we explored the roles and regulatory mechanisms of BATF in collagen-induced arthritis (CIA) in mice. METHODS: CIA and K/BxN serum transfer were used to generate inflammatory arthritis models in wild-type (WT) and Batf(-/-) mice. RA manifestations were determined by examining CIA incidence, clinical score, synovitis, synovial hyperplasia, angiogenesis in inflamed synovium, pannus formation, bone erosion, and cartilage destruction. Immune features in RA were analyzed by examining immune cell populations and cytokine production. RESULTS: BATF was upregulated in the synovial tissues of joints in which inflammatory arthritis had been caused by CIA or K/BxN serum transfer. The increases in CIA incidence, clinical score, and autoantibody production in CIA-induced WT mice were completely abrogated in the corresponding Batf(-/-) DBA/1 J mice. Genetic ablation of Batf also inhibited CIA-induced synovitis, synovial hyperplasia, angiogenesis in synovial tissues, pannus formation, bone erosion, and cartilage destruction. Batf knockout inhibited the differentiation of T helper (Th)17 cells and the conversion of CD4(+)Foxp3(+) cells to CD4(+)IL-17(+) cells. However, BATF did not modulate the functions of fibroblast-like synoviocytes (FLS), including the expressions of chemokines, matrix-degrading enzymes, vascular endothelial growth factor, and receptor activator of NF-κB ligand (RANKL). CONCLUSION: Our findings indicate that BATF crucially mediates CIA by regulating Th cell differentiation without directly affecting the functions of FLS.
29884228 Elevated levels of plasma symmetric dimethylarginine and increased arginase activity as po 2018 Jun 8 BACKGROUND: Rheumatoid arthritis (RA) patients are at high risk of developing cardiovascular disease (CVD). In RA, chronic inflammation may lead to endothelial dysfunction, an early indicator of CVD, owing to diminished nitric oxide (NO) production. Because L-arginine is the sole precursor of NO, we hypothesized that levels of L-arginine metabolic products reflecting NO metabolism are altered in patients with RA. METHODS: Plasma samples from patients with RA (n = 119) and age- and sex-matched control subjects (n = 238) were used for this study. Using LC-MS/MS, we measured plasma levels of free L-arginine, L-ornithine, L-citrulline, L-N(G)-monomethyl arginine (MMA), asymmetric dimethylarginine (ADMA), and symmetric dimethylarginine (SDMA). We compared global arginine bioavailability ratio (GABR) (i.e., ratio of L-arginine to L-ornithine + L-citrulline) and arginine methylation index (ArgMI) (i.e., ADMA + SDMA/MMA) in patients with RA vs. control subjects. Plasma arginase activity was measured using a sensitive arginase assay kit. The relationship of L-arginine metabolites and arginase activity to CVD risk factors was evaluated using Pearson's chi-square test. RESULTS: Compared with healthy control subjects, the RA cohort showed significantly lower levels of plasma L-arginine (46.11 ± 17.29 vs. 74.2 ± 22.53 μmol/L, p < 0.001) and GABR (0.36 ± 0.16 vs. 0.73 ± 0.24, p < 0.001), elevated levels of ADMA (0.76 ± 0.12 vs. 0.62 ± 0.12 μmol/L, p < 0.001), SDMA (0.54 ± 0.14 vs. 0.47 ± 0.13 μmol/L, p < 0.001), and ArgMI (6.51 ± 1.86 vs. 5.54 ± 1.51, p < 0.001). We found an approximately fourfold increase in arginase activity (33.8 ± 1.1 vs. 8.4 ± 0.8 U/L, p < 0.001), as well as elevated levels of arginase-mediated L-arginine catalytic product L-ornithine (108.64 ± 30.26 vs. 69.3 ± 20.71 μmol/L, p < 0.001), whereas a nitric oxide synthase (NOS) catalytic product, the L-citrulline level, was diminished in RA (30.32 ± 9.93 vs. 36.17 ± 11.64 μmol/L, p < 0.001). Patients with RA with existing CVD had higher arginase activity than patients with RA without CVD (p = 0.048). CONCLUSIONS: Global L-arginine bioavailability was diminished, whereas plasma arginase activity, ADMA, and SDMA levels were elevated, in patients with RA compared with healthy control subjects. Plasma SDMA was associated with hypertension and hyperlipidemia in patients with RA. This dysregulated L-arginine metabolism may function as a potential indicator of CVD risk in patients with RA.
30311063 Prevalence of degenerative joint disease of the temporomandibular joint: a systematic revi 2019 May OBJECTIVES: The purpose of this systematic review was to evaluate evidence about the prevalence of degenerative joint disease (DJD) of the temporomandibular joints (TMJ). MATERIALS AND METHODS: We performed search on electronic databases and gray literature from their inception to January 2018. Studies reporting prevalence data of DJD on TMJ were included. DJD was assessed through clinical and imaging diagnosis. Studies risk of bias was evaluated using the Critical Appraisal Checklist for Studies Reporting Prevalence Data. RESULTS: From 1082 studies, 32 were identified, and the sample size included 3435 subjects. They were clustered into two groups: the first comprised studies that reported prevalence of DJD in TMJ secondary to rheumatic systemic diseases like juvenile idiopathic arthritis (JIA) and rheumatoid arthritis (RA) and the second group comprised studies that reported prevalence of DJD on temporomandibular disorder patients. The prevalence of DJD on JIA patients ranged from 40.42% (n = 47) to 93.33% (n = 15) and on RA patients from 45.00% (n = 20) to 92.85% (n = 56). Among TMD patients, the prevalence of DJD reported according to patients ranged from 18.01% (n = 1038) to 84.74% (n = 118) and reported according to joints ranged from 17.97% (n = 178) to 77.23% (n = 224). CONCLUSION: This review attempts to high prevalence of DJD in patients with systemic rheumatic disease and a less prevalent, but still high, occurrence in patients with TMD without systemic involvement. CLINICAL RELEVANCE: Specialist doctors and dentists should be alert to not underestimate and to correctly diagnose DJD of the TMJ early in patients with rheumatic disease and TMD.
29605707 Epigenome-wide association studies for systemic autoimmune diseases: The road behind and t 2018 Nov Epigenetics is known to be an important mechanism in the pathogenesis of autoimmune diseases. Epigenetic variations can act as integrators of environmental and genetic exposures and propagate activated states in immune cells. Studying epigenetic alterations by means of genome-wide approaches promises to unravel novel molecular mechanisms related to disease etiology, disease progression, clinical manifestations and treatment responses. This paper reviews what we have learned in the last five years from epigenome-wide studies for three systemic autoimmune diseases, namely systemic lupus erythematosus, primary Sjögren's syndrome, and rheumatoid arthritis. We examine the degree of epigenetic sharing between different diseases and the possible mediating role of epigenetic associations in genetic and environmental risks. Finally, we also shed light into the use of epigenetic markers towards a better precision medicine regarding disease prediction, prevention and personalized treatment in systemic autoimmunity.
29802743 Fracture healing in a collagen-induced arthritis rat model: Radiology and histology eviden 2018 Nov This research was designed to investigate the fracture healing pattern in a rheumatoid arthritis (RA) rat model. A mid-shaft femur fracture (RA + F) model and normal fracture (NF) model as control were established. Micro-CT, H&E staining, TB staining, SO staining, tartrate-resistant acid phosphates, and immunohistochemistry test were performed. In the micro-CT images and H&E stains, fracture gaps were evident in the RA + F group 4 and 8 weeks after fracture. In detail, the bone mineral density, the ratio of bone volume to tissue volume, and trabecular thickness of the RA + F group were significantly lower than those of the NF group at all time points. Trabecular number value was significantly lower in the RA + F group 4 weeks after surgery in comparison with that of the NF group. Furthermore, the structure model index test result of the RA + F group was significantly higher than that of the NF group at all time points. TB staining and SO staining test results showed that the NF group had more cartilaginous callus in the earlier stage of bone healing process (4 weeks), and less cartilage callus formation in the later stage (8 weeks) in comparison with that of the RA + F group. Osteoclasts statistics score in the NF group were obviously lower than that of the RA + F group at all time points. MMP-3 and OPN protein levels of the fracture area in the RA + F group were significantly higher than those in the NF group. This study improves the understanding of the bone healing characteristics in patients with RA. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2876-2885, 2018.
29338762 Predictors of remission with etanercept-methotrexate induction therapy and loss of remissi 2018 Jan 16 BACKGROUND: The aim was to analyze characteristics that predict remission induction and subsequent loss of remission in patients with moderately active rheumatoid arthritis (RA) who received full-dose combination etanercept plus methotrexate induction therapy followed by reduced-dose etanercept or etanercept withdrawal. METHODS: Patients with Disease Activity Score based on 28-joint count (DAS28) >3.2 and ≤5.1 received open-label etanercept 50 mg once weekly (QW) plus methotrexate for 36 weeks. Those who achieved DAS28 low disease activity by 36 weeks were randomized to double-blind treatment with etanercept 50 mg or 25 mg QW plus methotrexate or placebo plus methotrexate for 52 weeks. All analyses were adjusted for the continuous baseline variables of their respective remission outcomes. RESULTS: Younger age, body mass index (BMI) <30 kg/m(2), and lower Health Assessment Questionnaire (HAQ) score at baseline were significant predictors of week-36 remission (P < 0.05) based on DAS28, Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI). Baseline DAS28, SDAI, and CDAI were significantly predictive of all three remission endpoints (P < 0.05). For all three treatments, the strongest predictors of loss of DAS28 remission included failure to achieve sustained remission (DAS28 < 2.6 at weeks 12, 20, 28, and 36) with induction therapy, higher DAS28/SDAI/CDAI at randomization and at 1 month, increase in DAS28/SDAI/CDAI at 1 month, and increase in DAS28/CDAI/SDAI components and patient-reported outcomes (PROs) at 1 month. With the exception of not achieving sustained remission, very similar significant predictors were observed for loss of SDAI and CDAI remission. CONCLUSION: These findings suggest that patients with moderately active RA who are younger and have lower BMI, lower HAQ, and lower disease activity at baseline are most likely to achieve remission when receiving combination etanercept and methotrexate induction therapy. In addition, patients who fail to achieve sustained remission with induction therapy and those with worse disease activity and PROs at early time points after initiating maintenance therapy with a full-dose or reduced-dose etanercept-methotrexate regimen or methotrexate monotherapy are most likely to lose remission across all treatment arms. These findings may help guide clinicians' decision-making as they treat patients to remission and beyond. TRIAL REGISTRATION: ClinicalTrials.gov, NCT00565409 . Registered on 28 November 2007.
28834390 Implementation of Treat-to-Target for Rheumatoid Arthritis in the US: Analysis of Baseline 2018 May OBJECTIVE: A treat-to-target (TTT) strategy is recommended in rheumatoid arthritis (RA). However, health care providers' adherence to TTT in clinical practice remains unclear. We examined adherence to TTT in RA at US rheumatology sites. METHODS: We used baseline information from the randomized controlled Treat-to-Target in RA: Collaboration to Improve Adoption and Adherence trial, which recruited 641 patients from 46 providers practicing at 11 US sites. We obtained data on the implementation of TTT, patient covariates, provider characteristics, and site variables. We examined the implementation of TTT using 4 cardinal features: recording a disease target, recording a disease activity measure, engaging in shared decision-making, and changing treatment if not at disease target. These features were assessed across sites and providers. We calculated a TTT implementation score as the percentage of features noted. We examined the association between patient, provider, and site covariates and TTT implementation score using proportional odds models. RESULTS: The implementation of TTT at baseline was suboptimal: 64.3% of visits had none of the TTT components present, 33.1% had 1 component, 2.3% had 2 components, and 0.3% had all components. The implementation of TTT was significantly different across providers and sites (P < 0.0001 for all). In the multivariable model, we observed that more experience as a rheumatologist was associated with a higher implementation score (P = 0.01 for trend). Compared with fellows, providers with >20 years of experience in practice were more likely to have more TTT components recorded (odds ratio 7.68 [95% confidence interval 1.46-40.52]). CONCLUSION: We found that adherence to a TTT strategy in RA was suboptimal, and it differed across providers and sites.
29303700 The eumusc.net standards of care for rheumatoid arthritis: importance and current implemen 2018 Mar OBJECTIVES: The eumusc.net standards of care (SOCs) for rheumatoid arthritis (RA) aimed to improve quality of care across Europe. This study investigated importance and implementation of each standard according to patients and health care professionals (HCPs) in the Netherlands and identified barriers towards implementation. METHODS: Dutch patients, rheumatologists and rheumatology nurses rated importance and implementation (0-10 numeric rating scale (NRS); 10=most important/best implemented) for each of the 20 SOCs. A care gap, adjusted for importance, was calculated: (100=highest gap). Statistical differences between a) patients and HCPs and b) subgroups of patients (demographics, health) were tested. Additionally, patients indicated agreement (0-10) with 6 implementation barriers. RESULTS: 386 patients and 91 HCPs were included. Both ranked adequate disease modifying anti-rheumatic drug treatment (9.3(SD1.2), 9.2(SD0.8)), access to care in emergencies (9.2(SD1.2), 9.2(SD1.0)) and regular re-appraisal when treatment fails (9.2(SD1.3), 9.0(SD1.0)) the most important SOCs, and these were among the best implemented (NRS≥8.5) SOCs. After accounting for applicability, patients and HCP identified care gaps for early diagnosis (25.5(SD32.0), 22.3(SD16.3)), availability of a treatment plan (25.1(SD22.7), 25.7(SD18.5)) and patients also for a regular schedule of assessment of disease (28.6(SD25.5)).Patients with poorer health or higher education scored systematically lower on care received while sharing similar priorities. Patients and HCPs considered limited reimbursement of specific health services a main barrier for implementation and patients additionally identified limited time of physicians. CONCLUSIONS: Dutch patients and HCPs overall agreed on priorities in care and found relevant SOCs well implemented. However, suggestions for improvement were raised especially by patients with poorer health and/or higher education.
29422084 Anti-CD11b antibody treatment suppresses the osteoclast generation, inflammatory cell infi 2018 Feb 8 BACKGROUND: Previously we established an arthritis-prone FcγRIIB-deficient mouse strain (designated KO1). Anti-mouse CD11b mAb (5C6) has been reported to inhibit the recruitment of peripheral CD11b(+) myelomonocytic cells from the blood to the inflammatory site. These cells include neutrophils and monocytes, both of which play important roles in the development of arthritis. Here we treated KO1 mice with 5C6 mAb in order to study its effect on arthritis development. METHODS: To evaluate the disease-preventive effect of 5C6, 4-month-old preclinical KO1 mice were divided into three groups: the first treated with 5C6 for 6 months, the second treated with normal rat IgG for 6 months, as a control, and the third left untreated. Arthritis severity and immunological abnormalities were compared among the groups, along with transcriptional levels of several important arthritis-related factors in ankle joints, spleen, and peripheral blood cells. RESULTS: The 5C6 treatment ameliorated arthritis in KO1 mice, showing decreases in inflammatory cell infiltration and osteoclast formation. Analysis of transcriptional levels in ankle joints revealed that compared with the two control groups, the 5C6-treated group showed downregulated expression of RANK, RANKL, MCP-1, RANTES, TNFα, and IL-6, and at the same time showed significantly up-regulated expression of the decoy receptor for RANKL, i.e. osteoprotegerin. In addition, the disease suppression was associated with the lower serum levels of autoantibodies, and the decreased frequencies of activated B cells and plasma cells. The expression levels of B cell activation/differentiation-related cytokines were suppressed in spleen and peripheral leukocytes of the 5C6-treated mice. Intriguingly, while untreated KO1 mice spontaneously developed marked monocytosis, the 5C6-treated mice showed the significantly down-regulated frequency of monocytes. CONCLUSIONS: The outcome of 5C6 treatment was complex, in which the 5C6-mediated disease-preventive effect is likely due on one hand to the decrease in the recruitment of inflammatory cells and osteoclast precursor monocytes from the periphery into the joints, and on the other hand to the suppression of B cell activation/maturation and of autoantibody production via the suppression of B cell stimulating cytokine production. The lower levels of these cytokines may be the secondary effect of the lower frequency of monocytes, since monocytes/macrophages are the major producers of these cytokines.
29378619 Chromosome conformation signatures define predictive markers of inadequate response to met 2018 Jan 29 BACKGROUND: There is a pressing need in rheumatoid arthritis (RA) to identify patients who will not respond to first-line disease-modifying anti-rheumatic drugs (DMARD). We explored whether differences in genomic architecture represented by a chromosome conformation signature (CCS) in blood taken from early RA patients before methotrexate (MTX) treatment could assist in identifying non-response to DMARD and, whether there is an association between such a signature and RA specific expression quantitative trait loci (eQTL). METHODS: We looked for the presence of a CCS in blood from early RA patients commencing MTX using chromosome conformation capture by EpiSwitchâ„¢. Using blood samples from MTX responders, non-responders and healthy controls, a custom designed biomarker discovery array was refined to a 5-marker CCS that could discriminate between responders and non-responders to MTX. We cross-validated the predictive power of the CCS by generating 150 randomized groups of 59 early RA patients (30 responders and 29 non-responders) before MTX treatment. The CCS was validated using a blinded, independent cohort of 19 early RA patients (9 responders and 10 non-responders). Last, the loci of the CCS markers were mapped to RA-specific eQTL. RESULTS: We identified a 5-marker CCS that could identify, at baseline, responders and non-responders to MTX. The CCS consisted of binary chromosome conformations in the genomic regions of IFNAR1, IL-21R, IL-23, CXCL13 and IL-17A. When tested on a cohort of 59 RA patients, the CCS provided a negative predictive value of 90.0% for MTX response. When tested on a blinded independent validation cohort of 19 early RA patients, the signature demonstrated a true negative response rate of 86 and a 90% sensitivity for detection of non-responders to MTX. Only conformations in responders mapped to RA-specific eQTL. CONCLUSIONS: Here we demonstrate that detection of a CCS in blood in early RA is able to predict inadequate response to MTX with a high degree of accuracy. Our results provide a proof of principle that a priori stratification of response to MTX is possible, offering a mechanism to provide alternative treatments for non-responders to MTX earlier in the course of the disease.
30384579 Paricalcitol inhibits the Wnt/beta-catenin signaling pathway and ameliorates experimentall 2018 Oct 31 Background/aim: The Wnt/ß-catenin pathway has important biological activities, including the differentiation of cells and joint formations. The aim of our study was to determine the effect of paricalcitol on experimentally induced arthritis. Materials and methods: Type II collagen combined with Freund's adjuvant was applied to induce arthritis in Wistar albino female rats. Paricalcitol (0.3 μg/kg daily) was subcutaneously injected starting 1 day after collagen applications (prophylactic group) or 1 day after the onset of arthritis (therapeutic group), until day 29. Results: The 29th day arthritis scores were lower compared to the 13th day scores in the paricalcitol groups (P < 0.05), while they were higher in the arthritis group (P < 0.05). Marked cartilage-bone destruction and extensive perisynovial inflammation were detected in the arthritis group. Decreased cartilage-bone destruction and perisynovial inflammation in the paws were observed in the paricalcitol groups. The tissue mRNA levels of DKK1, Wnt5a, and axin-2 were higher in the arthritis group than in the control group. In the paricalcitol groups, mRNA expressions were lower than in the arthritis group. Conclusion: The present study shows that the Wnt/ß-catenin signaling pathway is active in arthritis. Moreover, paricalcitol ameliorates arthritis via inhibiting the Wnt/ß-catenin pathway. Paricalcitol and the Wnt/ß-catenin pathway are candidates for research in human rheumatoid arthritis.
29720252 Estrogen induces St6gal1 expression and increases IgG sialylation in mice and patients wit 2018 May 2 BACKGROUND: Rheumatoid arthritis (RA) preferentially affects women, with the peak incidence coinciding with estrogen decrease in menopause. Estrogen (E2) may therefore have intrinsic immune-regulatory properties that vanish with menopause. Fc sialylation is a crucial factor determining the inflammatory effector function of antibodies. We therefore analyzed whether E2 affects immunoglobulin G (IgG) sialylation. METHODS: Postmenopausal (ovariectomized) mice were immunized with ovalbumin and treated with E2 or vehicle. Total and ovalbumin-specific IgG concentrations, sialylation, and Fcγ receptor expression were analyzed. Postmenopausal women with RA receiving hormone replacement therapy, including E2, or no treatment were analyzed for IgG sialylation. Furthermore, effects of E2 on the expression of the sialylation enzyme β-galactoside α2,6-sialyltransferase 1 (St6Gal1) were studied in mouse and human antibody-producing cells. RESULTS: E2 treatment significantly increased Fc sialylation of total and ovalbumin-specific IgG in postmenopausal mice. Furthermore, E2 led to increased expression of inhibitory Fcγ receptor IIb on bone marrow leukocytes. Treatment with E2 also increased St6Gal1 expression in mouse and human antibody-producing cells, providing a mechanistic explanation for the increase in IgG-Fc sialylation. In postmenopausal women with RA, treatment with E2 significantly increased the Fc sialylation of IgG. CONCLUSIONS: E2 induces anti-inflammatory effector functions in IgG by inducing St6Gal1 expression in antibody-producing cells and by increasing Fc sialylation. These observations provide a mechanistic explanation for the increased risk of RA in conditions with low estrogen levels such as menopause.
30537799 Collagen II-primed Foxp3 Transduced T Cells Ameliorate Collagen-induced Arthritis in Rats: 2018 Aug 12 Regulatory T cells (Tregs) play a major role in the prevention of autoimmune diseases. Transfer of Foxp3 gene into conventional T cells converts their phenotype to regulatory T cells. Therefore, the question arises as to whether adoptively transferred in vitro differentiated Treg cells specific for a locally expressed antigen might have better inhibitory effects on the progression of the disease as compared with antigen-nonspecific T reg cells. Herein, we investigated the therapeutic potential of primed and unprimed retrovirus mediated Foxp3-overexpression T cells following intravenously injected of these cells into affected rats with collagen-induced arthritis (CIA), an animal model of rheumatoid arthritis. Our analyses demonstrate that systemic administration of collagen II primed Foxp3-transduced T cells could markedly ameliorate CIA inflammatory responses at clinical (p<0.0014) and pathological exchanges including cellular infiltration (p=0.002), bone erosion (p=0.0013) and synovial hyperplasia (p=0.002). In contrast, collagen II unprimed Foxp3-transduced T cells like as collagen II primed or unprimed GFP-transduced T cells did not reveal any beneficial effects on arthritis features as compared with untreated group (p>0.05). Therefore, we believe that collagen II primed Foxp3-transduced T cells are interacting locally and systemically with immune cells which reveled with decreasing of T cells infiltration into joints along with specific CII IgG production. Considering the results described here, it appears that the using patients' T cells which previously exposed to specific antigens may have more effective therapeutic advantage in the production of induced regulatory T cells in the treatment of arthritis.
29080328 Clinical and functional significance of STEAP4-splice variant in CD14(+) monocytes in pati 2018 Mar Tumour necrosis factor alpha (TNF)-α-induced adipose-related protein (TIARP) is a negative regulator of inflammation in arthritis model mice. In humans, six-transmembrane epithelial antigen of prostate 4 (STEAP4) (human counterpart of TIARP) is also expressed in CD14(+) monocytes from patients with rheumatoid arthritis (RA). Recently, highly levels of exon 3-spliced variant STEAP4 (v-STEAP4) expression have been observed in porcine lung. The aim of this study is to elucidate the expression and functional role of v-STEAP4, comparing it with that of STEAP4, in the pathogenesis of arthritis. We identified v-STEAP4 in CD14(+) cells. The expression of STEAP4 and v-STEAP4 was higher in patients with RA than in healthy participants. We also found that STEAP4 and v-STEAP4 were correlated positively with C-reactive protein and that their expression was decreased after treatment with an interleukin (IL)-6 antagonist in patients with RA. To investigate further the role of STEAP4 and v-STEAP4, we produced STEAP4 and v-STEAP4 over-expressing human monocytic cell lines (THP-1) for functional analysis. In the v-STEAP4 over-expressing cells, the production of IL-6 was suppressed significantly, but TNF-α was increased significantly through lipopolysaccharide (LPS) stimulation. Immunoblot analysis revealed that phosphorylated (p-)nuclear factor kappa B (NF-κB) was increased after LPS stimulation and degradation of nuclear factor kappa B inhibitor alpha (IκBα) was sustained, whereas p-signal transducer and activator of transcription 3 (STAT-3) was decreased with v-STEAP4. We identified specific up-regulation of v-STEAP4 in RA monocytes. V-STEAP4 might play a crucial role in the production of TNF-α and IL-6 through NF-κB and STAT-3 pathways, resulting in the generation of RA.
30591403 Crosstalk between tumor necrosis factor-alpha signaling and aryl hydrocarbon receptor sign 2019 Mar OBJECTIVES: To examine the influence of smoking on biologics treatment against different therapeutic targets, such as TNFα, IL-6, and T cell, in rheumatoid arthritis (RA) and elucidate the underlying molecular mechanism. METHODS: The association between drug-discontinuation due to poor therapeutic response and smoking status was analyzed individually in biologics against different therapeutic targets by a multivariable logistic regression analysis using the "NinJa" Registry, one of the largest cohorts of Japanese RA patients. In vitro enhancement of TNFα-induced NF-κB activation and subsequent proinflammatory cytokine production by cigarette chemical components was examined by RT-PCR, qPCR, ELISA, and western blotting using an immortalized rheumatoid synovial cell line, MH7A. RESULTS: The rate of drug-discontinuation due to poor therapeutic response was higher in the current smoking group than in the never- or ever-smoking groups (the odds ratio of current/never smoking: 2.189, 95%CI; 1.305-3.672,P = 0.003; current/ever: 1.580, 95%CI; 0.879-2.839,P = 0.126) in the TNF inhibitor (TNFi) treatment group. However, this tendency was not observed in either the IL-6 or T cell inhibitor treatment groups. Cigarette smoke chemical components, such as benzo[α]pyrene, known as aryl hydrocarbon receptor (AhR) ligands, themselves activated NF-κB and induced proinflammatory cytokines, IL-1β and IL-6. Furthermore, they also significantly enhanced TNFα-induced NF-κB activation and proinflammatory cytokine production. This enhancement was dominantly inhibited by Bay 11-7082, an NF-κB inhibitor. CONCLUSIONS: These results suggest a crosstalk between TNFα signaling and AhR signaling in NF-κB activation which may constitute one of the molecular mechanisms underlying the higher incidence of drug-discontinuation in RA patients undergoing TNFi treatment with smoking habits.
30217117 Safety and effectiveness of abatacept in Japanese non-elderly and elderly patients with rh 2019 Sep Objectives: To investigate the safety, effectiveness, and risk-benefit balance of intravenous abatacept (ABA) in non-elderly (<65 years: NEG) and elderly (≥65 years: EG) rheumatoid arthritis patients. Methods: This sub-analysis of an all-cases postmarketing surveillance in Japan assessed safety in all enrolled patients and effectiveness in those with Disease Activity Score 28 based on C-reactive protein (DAS28-CRP) measurements at ≥2 time points including baseline. Risk-benefit was evaluated based on infections and DAS28-CRP improvement >1.2. Results: The NEG and EG of the safety analysis set comprised 2,170 and 1,712 patients, respectively; corresponding 6-month ABA retention rates were 80.2% and 77.1%. The NEG had fewer adverse drug reactions (14.5% vs. 17.2%, p = .021) and infections (4.8% vs. 7.2%, p = .002) than the EG. DAS28-CRP changed similarly between groups. The proportion of patients with low-risk/high-benefit and high-risk/low-benefit were 33.1% and 6.9% (NEG) and 29.7% and 9.0% (EG). Low-risk/high-benefit patients were younger, had shorter disease duration and fewer comorbidities, and were with less use of oral glucocorticoid and prior biologics, more use of methotrexate and higher DAS28-CRP than high-risk/low-benefit patients at baseline. Conclusion: ABA was well tolerated and similarly efficacious in the EG and NEG. Identification of factors related to low-risk/high-benefit may aid appropriate patient selection.