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ID PMID Title PublicationDate abstract
30346187 Capturing patients' symptom expression and spouses' cardiovascular responses continuously: 2018 Dec INTRODUCTION: Spousal caregivers face increased cardiovascular risks; lab studies suggest that autonomic reactivity to patients' physical suffering may play a role. To evaluate this mechanism in daily life, our pilot study characterized the feasibility of recruiting couples for a multimethod, in-home assessment. We examined the usability of the resulting data in an effort to link spousal cardiovascular changes to patient pain expression during couples' everyday interactions. METHOD: For two 48-hr periods, individuals with rheumatoid arthritis (RA) and their partners wore heart monitors while audio-recordings captured couples' in-home interactions. Interbeat intervals were subsetted in 1-, 2-, and 5-min windows before and after each pain expression. Pre-post difference scores in high-frequency heart rate variability (HF-HRV) and heart rate were examined. RESULTS: Of the 17 screened RA patients, 11 were ineligible, and 3 partners declined. The 3 participating couples completed all study activities. The resulting 288 hr of recordings were coded for patients' RA symptom expression, which varied from none to an average of 11 times daily. One couple had sufficient data for physiological analysis: Contrary to prediction, spouse HF-HRV significantly increased after patient symptom expression. CONCLUSIONS: Recruitment rates mirrored other couples studies, and enrolled couples complied with study procedures. In-home conversations were reliably coded and successfully linked to spousal ongoing cardiovascular activity. Preliminary findings highlight the importance of optimal sampling windows and suggest symptom expression as a relevant process for some spouses but not others. We offer recommendations for efficiently scaling up the method in future studies. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
29280011 High burden of adverse events is associated with reduced remission rates in early rheumato 2018 Jun Adverse events (AEs) are common during disease-modifying antirheumatic drug (DMARD) treatment, but their influence on treatment results is unclear. We studied AEs in relation to disease activity in early rheumatoid arthritis (RA). Ninety-nine patients started intensive treatment with three conventional synthetic DMARDs (csDMARDs) and oral prednisolone, and were randomized to a 6-month induction treatment with infliximab or placebo. All AEs during the first 12 months of treatment were recorded. We scored each AE based on severity (scale 1-4) and defined the burden of AEs as the sum of these scores. Patients were divided into tertiles according to the burden of AEs. As outcomes, we assessed 28-joint disease activity score (DAS28) levels and remission rates at 12 and 24 months. Three hundred thirty-one AEs in 99 patients were reported, and 27 (8%) were categorized as severe or serious. Mean burden of AEs per patient was 5.4 ± 4.3. Seventy-nine AEs (24%) led to temporary (n = 52) or permanent (n = 27) csDMARD discontinuation. Of discontinuations, 1, 21, and 57 were detected in the first, second, and third tertiles, respectively. DAS28 remission rates decreased across tertiles at 12 months (94, 94, and 76%; p for linearity 0.029) and at 24 months (90, 86, and 70%; p for linearity 0.021). Mean DAS28 levels increased across tertiles at 12 months (1.5 ± 1.0, 1.7 ± 0.9, and 1.9 ± 1.2; p for linearity 0.021) and at 24 months (1.4 ± 0.8, 1.6 ± 1.0, and 1.9 ± 1.1; p for linearity 0.007). High burden of AEs is associated with higher disease activity and lower likelihood of remission in early RA.
29148078 Soluble TAM receptor tyrosine kinases in rheumatoid arthritis: correlation with disease ac 2018 Apr The TAM receptor tyrosine kinases (TAM RTK) are a subfamily of receptor tyrosine kinases, the role of which in autoimmune diseases such as systemic lupus erythematosus has been well explored, while their functions in rheumatoid arthritis (RA) remain largely unknown. In this study, we investigated the role of soluble TAM receptor tyrosine kinases (sAxl/sMer/sTyro3) in patients with RA. A total of 306 RA patients, 100 osteoarthritis (OA) patients and 120 healthy controls (HCs) were enrolled into this study. The serum concentrations of sAxl/sMer/sTyro3 were measured by enzyme-linked immunosorbent assay (ELISA), then the associations between sAxl/sMer/sTyro3 levels and clinical features of RA patients were analysed. We also investigated whether sTyro3 could promote osteoclast differentiation in vitro in RA patients. The results showed that compared with healthy controls (HCs), sTyro3 levels in the serum of RA patients were elevated remarkably and sMer levels were decreased significantly, whereas there was no difference between HCs and RA patients on sAxl levels. The sTyro3 levels were correlated weakly but positively with white blood cells (WBC), immunoglobulin (Ig)M, rheumatoid factor (RF), swollen joint counts, tender joint counts, total sharp scores and joint erosion scores. Conversely, there were no significant correlations between sMer levels and the above indices. Moreover, RA patients with high disease activity also showed higher sTyro3 levels. In-vitro osteoclast differentiation assay showed further that tartrate-resistant acid phosphatase (TRAP)(+) osteoclasts were increased significantly in the presence of sTyro3. Collectively, our study indicated that serum sTyro3 levels were elevated in RA patients and correlated positively with disease activity and bone destruction, which may serve as an important participant in RA pathogenesis.
29922913 Effectiveness of foot orthoses in patients with rheumatoid arthritis related to disability 2018 Dec BACKGROUND: Epidemiological studies consistently report a 90% prevalence of foot pain. Mechanical and other non-pharmacological interventions such as orthoses and footwear can play an important role in managing foot pathology in patients whose systemic disease is controlled. The effectiveness of treatment with insoles has been examined in various randomised controlled trials, which have reported immediate clinical improvements, with reduced foot pain and disability and enhanced functionality. The aim of this systematic review is to determine the effectiveness of foot orthoses in patients with rheumatoid arthritis (RA), in comparison with other treatments, in terms of enhanced disability and reduced pain. METHODS: A systematic review and meta-analysis was conducted of a number of randomised controlled trials focusing on patients with RA. The search was conducted in Cochrane, CINAHL, PubMed, EMBASE, SCOPUS and Cuiden, by means of an independent peer review. The Mesh terms and fields used were foot, ankle, joint, RA, foot, orthosis, insole and foot orthosis. RESULTS: Of the initial 118 studies considered, 5 were included in the final systematic review and meta-analysis. These five studies had enrolled a total of 301 participants, with follow-up periods ranging from 4 to 36 months. Although the use of orthoses seems to alleviate foot pain, our meta-analysis did not reveal statistically significant differences between control and intervention groups regarding long- and short-term pain relief and/or reduced disability. CONCLUSIONS: Foot orthoses can relieve pain and disability and enhance patients, but no significant differences were found between control and intervention groups.
29070529 Anticitrullinated protein/peptide antibody multiplexing defines an extended group of ACPA- 2018 Feb INTRODUCTION: The second generation anticycliccitrullinated peptide (anti-CCP2) assay detects the majority but not all anticitrullinated protein/peptide antibodies (ACPA). Anti-CCP2-positive rheumatoid arthritis (RA) is associated with HLA-DRB1* shared epitope (SE) alleles and smoking. Using a multiplex assay to detect multiple specific ACPA, we have investigated the fine specificity of individual ACPA responses and the biological impact of additional ACPA reactivity among anti-CCP2-negative patients. METHODS: We investigated 2825 patients with RA and 551 healthy controls with full data on anti-CCP2, HLA-DRB1* alleles and smoking history concerning reactivity against 16 citrullinated peptides and arginine control peptides with a multiplex array. RESULTS: The prevalence of the 16 ACPA specificities ranged from 9% to 58%. When reactivity to arginine peptides was subtracted, the mean diagnostic sensitivity increased by 3.2% with maintained 98% specificity. Of the anti-CCP2-negative patients, 16% were found to be ACPA positive. All ACPA specificities associated with SE, and all but one with smoking. Correction for arginine reactivity also conveyed a stronger association with SE for 13/16 peptides. Importantly, when all ACPA specificities were analysed together, SE and smoking associated with RA in synergy among ACPA positive, but not among ACPA-negative subjects also in the anti-CCP2-negative subset. CONCLUSIONS: Multiplexing detects an enlarged group of ACPA-positive but anti-CCP2-negative patients with genetic and environmental attributes previously assigned to anti-CCP2-positive patients. The individual correction for arginine peptide reactivity confers both higher diagnostic sensitivity and stronger association to SE than gross ACPA measurement.
28444172 Risk of venous thromboembolism in patients with psoriatic arthritis, psoriasis and rheumat 2018 Oct 14 AIMS: To determine the risk of venous thromboembolism (VTE) defined as the combined endpoint of deep venous thrombosis (DVT) and pulmonary embolism (PE) among patients with psoriatic arthritis (PsA), psoriasis and rheumatoid arthritis (RA) compared with population controls. METHODS AND RESULTS: A cohort study was conducted in a primary care medical record database in the UK with data from 1994-2014 among patients with PsA, RA, or psoriasis. Cox proportional hazards models were used to calculate the relative hazards for DVT, PE, and VTE. An interaction with disease modifying anti-rheumatic drugs (DMARD) was hypothesized a priori and was significant. Patients with PsA (n = 12 084), RA (n = 51 762), psoriasis (n = 194 288) and controls (n = 1 225 571) matched on general practice and start date were identified. Patients with RA (with and without a DMARD prescription) and patients with mild psoriasis had significantly elevated risks of VTE (HR 1.35, 1.29, and 1.07, respectively) after adjusting for traditional risk factors. Severe psoriasis and PsA prescribed a DMARD had an elevated but not statistically significant risk for VTE. Findings were similar for DVT. The age-and-sex-adjusted risk of PE was elevated in RA, severe psoriasis and PsA patients prescribed a DMARD. CONCLUSION: While systemic inflammation is a risk factor for VTE, the risk of VTE compared with controls is different among patients with three different inflammatory disorders: RA, PsA, and psoriasis.
29287311 Hypomethylation of CYP2E1 and DUSP22 Promoters Associated With Disease Activity and Erosiv 2018 Apr OBJECTIVE: Epigenetic modifications have previously been associated with rheumatoid arthritis (RA). In this study, we aimed to determine whether differential DNA methylation in peripheral blood cell subpopulations is associated with any of 4 clinical outcomes among RA patients. METHODS: Peripheral blood samples were obtained from 63 patients in the University of California, San Francisco RA cohort (all satisfied the American College of Rheumatology classification criteria; 57 were seropositive for rheumatoid factor and/or anti-cyclic citrullinated protein). Fluorescence-activated cell sorting was used to separate the cells into 4 immune cell subpopulations (CD14+ monocytes, CD19+ B cells, CD4+ naive T cells, and CD4+ memory T cells) per individual, and 229 epigenome-wide DNA methylation profiles were generated using Illumina HumanMethylation450 BeadChips. Differentially methylated positions and regions associated with the Clinical Disease Activity Index score, erosive disease, RA Articular Damage score, Sharp score, medication at time of blood draw, smoking status, and disease duration were identified using robust regression models and empirical Bayes variance estimators. RESULTS: Differential methylation of CpG sites associated with clinical outcomes was observed in all 4 cell types. Hypomethylated regions in the CYP2E1 and DUSP22 gene promoters were associated with active and erosive disease, respectively. Pathway analyses suggested that the biologic mechanisms underlying each clinical outcome are cell type-specific. Evidence of independent effects on DNA methylation from smoking, medication use, and disease duration were also identified. CONCLUSION: Methylation signatures specific to RA clinical outcomes may have utility as biomarkers or predictors of exposure, disease progression, and disease severity.
29683356 Is current smoking status and its relationship to anti-cyclic citrullinated peptide antibo 2018 Sep OBJECTIVE: To assess the association between smoking, anti-cyclic citrullinated peptide (anti-CCP) antibody status, and clinical efficacy of biological therapies in rheumatoid arthritis (RA) patients. METHOD: This retrospective clinical practice setting study included 1349 RA patients from the METEOR database (aged >18 years). We collected data on sociodemographics, smoking status (smoker, <10, 10-19, and >20 cigarettes/day; ex-smoker; non-smoker), baseline disease activity parameters and anti-CCP, previous disease-modifying anti-rheumatic drugs (DMARDs), biological therapy, combined therapy (steroids and DMARDs), and follow-up disease activity. Clinical efficacy was assessed by European League Against Rheumatism (EULAR) good/moderate response rates for all aggregated biological therapies, based on both smoking and anti-CCP status. RESULTS: The non-smoking RA patients were more often female at biological therapy initiation than the ex-smokers and smokers (91.1% vs 60.4% and 67.9%, respectively, p < 0.001), and ex-smokers were older than non-smokers and smokers (mean ± sd 56.5 ± 11.1, 53.5 ± 13.3 and 51.3 ± 11.0 years old, respectively; p < 0.001). In total, 845 (62.6%) were non-smokers, 214 (15.9%) ex-smokers, and 290 (21.5%) smokers [daily cigarettes smoked: 148 (11%) <11; 61 (4.5%) 11-20; and 81 (6%) >20]. Anti CCP-antibody status was similar in both groups. Non-smokers showed higher baseline DAS28 than ex-smokers and smokers (5.0 ± 1.5 vs 4.7 ± 1.4 and 4.7 ± 1.4, respectively; p < 0.001) and used more baseline steroids and DMARDs. A higher EULAR response rate was observed in non-smokers than in ex-smokers and smokers (73% vs 65% and 64.1%, respectively; p = 0.004). Drug survival was higher in non-smokers compared to ex-smokers and smokers [57.7 months (46.4-53.8), 38.6 (30.3-46.8), and 50.1 (41.8-58.4); p < 0.001, respectively]. CONCLUSION: In daily clinical practice, non-smokers respond better than smokers to biological therapy, but this does not result in better drug survival.
30223787 Data-driven human transcriptomic modules determined by independent component analysis. 2018 Sep 17 BACKGROUND: Analyzing the human transcriptome is crucial in advancing precision medicine, and the plethora of over half a million human microarray samples in the Gene Expression Omnibus (GEO) has enabled us to better characterize biological processes at the molecular level. However, transcriptomic analysis is challenging because the data is inherently noisy and high-dimensional. Gene set analysis is currently widely used to alleviate the issue of high dimensionality, but the user-defined choice of gene sets can introduce biasness in results. In this paper, we advocate the use of a fixed set of transcriptomic modules for such analysis. We apply independent component analysis to the large collection of microarray data in GEO in order to discover reproducible transcriptomic modules that can be used as features for machine learning. We evaluate the usability of these modules across six studies, and demonstrate (1) their usage as features for sample classification, and also their robustness in dealing with small training sets, (2) their regularization of data when clustering samples and (3) the biological relevancy of differentially expressed features. RESULTS: We identified 139 reproducible transcriptomic modules, which we term fundamental components (FCs). In studies with less than 50 samples, FC-space classification model outperformed their gene-space counterparts, with higher sensitivity (p < 0.01). The models also had higher accuracy and negative predictive value (p < 0.01) for small data sets (less than 30 samples). Additionally, we observed a reduction in batch effects when data is clustered in the FC-space. Finally, we found that differentially expressed FCs mapped to GO terms that were also identified via traditional gene-based approaches. CONCLUSIONS: The 139 FCs provide biologically-relevant summarization of transcriptomic data, and their performance in low sample settings suggest that they should be employed in such studies in order to harness the data efficiently.
29303005 Bone-targeted methotrexate-alendronate conjugate inhibits osteoclastogenesis in vitro and 2018 Nov Rheumatoid arthritis (RA), a disease that causes joint destruction and bone erosion, is related to osteoclast activity. RA is generally treated with methotrexate (MTX). In this study, a MTX-Alendronate (ALN) conjugate was synthesized and characterized. The conjugate dramatically inhibited osteoclast formation and bone resorption compared with MTX and ALN used alone or in combination. Due to the characteristics of ALN, the MTX-ALN conjugate can adhere to the exposed bone surface and enhance drug accumulation in the pathological region for targeted therapy against osteoclastogenesis. Additionally, MTX was rapidly released in the presence of lysozyme under mildly acidic conditions, similar to inflammatory tissue and osteoclast-surviving conditions, which contributes to inflammatory inhibition; this was confirmed by the presence of pro-inflammatory cytokines. Our study highlights the use of the MTX-ALN conjugate as a potential therapeutic approach for RA by targeting osteoclastogenesis.
30254017 Redox-active trace metal-induced release of high mobility group box 1(HMGB1) and inflammat 2018 Nov Rheumatoid arthritis (RA) is a chronic autoimmune systemic inflammatory disease that is characterized by synovial inflammation and bone erosion. We have investigated the mechanism(s) by which essential trace metals may initiate and propagate inflammatory phenotypes in synovial fibroblasts. We used HIG-82, rabbit fibroblast-like synovial cells (FLS), as a model system for potentially initiating RA through oxidative stress. We used potassium peroxychromate (PPC, Cr(+5)), ferrous chloride (FeCl(2,) Fe(+2)), and cuprous chloride (CuCl, Cu(+)) trace metal agents as exogenous pro-oxidants. Intracellular ROS was quantified by fluorescence microscopy and confirmed by flow cytometry (FC). Protein expression levels were measured by western blot and FC, while ELISA was used to quantify the levels of cytokines. Trace metal agents in different valence states acted as exogenous pro-oxidants that generate reactive oxygen species (ROS), which signal through TLR4 stimulation. ROS/TLR4- coupled activation resulted in the release of HMGB1, TNF-α, IL-1β, and IL-10 in conjunction with upregulation of myeloid-related protein (MRP8/14) inflammatory markers that may contribute to the RA pathophysiology. Our results indicate that oxidant-induced TLR4 activation can release HMGB1 in combination with other inflammatory cytokines to mediate pro-inflammatory actions that contribute to RA pathogenesis. The pathway by which inflammatory and tissue erosive changes may occur in this model system possibly underlies the need for functioning anti-HMGB1-releasing agents and antioxidants that possess both dual trace metal chelating and oxidant scavenging properties in a directed combinatorial therapy for RA.
29752727 Clinical periodontal status and inflammatory cytokines in primary Sjögren syndrome and rh 2018 Aug BACKGROUND: The aim of the present study is to compare the clinical periodontal findings as well as gingival crevicular fluid (GCF) and plasma levels of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), interferon gamma (IFN-γ) and caspase-1 in primary Sjögren syndrome (pSS) and rheumatoid arthritis (RA) subjects. METHODS: In the present case control study plasma and GCF samples were collected, full-mouth recordings comprising plaque index (PI), bleeding on probing (BOP) and probing depth (PD) were performed in 44 subjects with pSS, 39 subjects with RA and 30 systemically healthy subjects. Plasma and GCF TNF-α, IL-1β, IFN-gamma and caspase-1 levels were determined by enzyme-linked immunosorbent assay. RESULTS: There were no differences in GCF and plasma levels of IFN-γ and TNF-α in all the study groups (p > 0.05). GCF levels of IL-1β were higher in pSS group than healthy group (p = 0.035). Caspase-1 GCF levels were significantly higher in pSS group than RA group (p = 0.032). Highest plasma IL-1β levels were detected in pSS compared to RA and healthy groups (p < 0.001). Healthy group has higher caspase-1 plasma levels than pSS and RA groups (p < 0.001). CONCLUSIONS: The results of the present study reveal that the periodontal status of patients with pSS does not differ from systemically healthy subjects. Further studies involving longitudinal assessments on larger populations with standardized patient inclusion criteria are needed to confirm the findings.
29652792 Influence of Blue Mussel (Mytilus edulis) Intake on Disease Activity in Female Patients wi 2018 Apr 13 Rheumatoid Arthritis (RA) is a chronic inflammatory disease. This study evaluates the effect of blue mussel intake on disease activity and quality of life in women with RA. Thirty-nine women with established RA and a disease activity score 28 (DAS28) >3.0 were recruited to a randomized 2 × 11-week cross-over dietary intervention. The participants continued with their medication and habitual diet and exchanged one cooked meal a day, five days a week, with a meal including 75 g blue mussels or 75 g meat. Diets were switched after an eight week washout period. Data regarding quality of life (SF-36), blood lipids, erythrocyte sediment rate (ESR), C-reactive protein (CRP) and tender and swollen joints were examined at the start and end of each dietary period. Thirty women completed one period, and twenty-three completed both. Intake of the blue mussel diet led to a significant reduction of DAS28-CRP (p = 0.048), but not DAS28. The number of EULAR (European League Against Rheumatism) criteria moderate and good responders were higher when consuming blue mussel diet (p = 0.036). Blood lipids did not change. To conclude, blue mussel intake reduced disease symptoms in women with RA and improved perceived health. The reported effects need to be confirmed by non-patient reported outcomes, such as inflammation markers.
29764963 Reducing Missed Opportunities for Influenza Vaccination in Patients with Rheumatoid Arthri 2018 Aug OBJECTIVE: To assess a multimodal intervention for reducing missed opportunities for outpatient influenza vaccination in individuals with rheumatoid arthritis (RA). METHODS: Patients with RA were enrolled from a single center and each rheumatology outpatient visit was tracked for missed opportunities for influenza vaccination, defined as a visit in which an unvaccinated patient without contraindications remained unvaccinated or lacked documentation of vaccine recommendation in the electronic medical record (EMR). Providers then received a multimodal intervention consisting of an education session, EMR alerts, and weekly provider-specific e-mail reminders. Missed opportunities before and after the intervention were compared, and the determinants of missed opportunities were analyzed. RESULTS: A total of 228 patients with RA were enrolled (904 preintervention visits) and 197 returned for at least 1 postintervention visit (721 postintervention visits). The preintervention frequency of any missed opportunities for influenza vaccination was 47%. This was reduced to 23% postintervention (p < 0.001). Among those vaccinated, the relative hazard for influenza vaccination post- versus preintervention period was 1.24 (p = 0.038). Younger age, less frequent office visits, higher erythrocyte sedimentation rate, and negative attitudes about vaccines were each independently associated with missed opportunities preintervention. Postintervention, these factors were no longer associated with missed opportunities; however, the intervention was not as effective in non-Hispanic black patients, non-English speakers, those residing outside of the New York City metropolitan area, and those reporting prior adverse reactions to vaccines. CONCLUSION: Improved uptake of influenza vaccination in patients with RA is possible using a multimodal approach. Certain subgroups may need a more potent intervention for equivalent efficacy.
29738359 Genomic Profile and Pathologic Features of Diffuse Large B-Cell Lymphoma Subtype of Methot 2018 Jul Rheumatoid arthritis patients often develop the diffuse large B-cell lymphoma subtype of methotrexate-associated lymphoproliferative disorder (DLBCL). We characterized the genomic profile and pathologic characteristics of 20 biopsies using an integrative approach. DLBCL was associated with extranodal involvement, a high/high-intermediate international prognostic index in 53% of cases, and responded to MTX withdrawal. The phenotype was nongerminal center B-cell in 85% of samples and Epstein-Barr encoding region positive (EBER) in 65%, with a high proliferation index and intermediate MYC expression levels. The immune microenvironment showed high numbers of CD8 cytotoxic T lymphocytes and CD163 M2 macrophages with an (CD163/CD68) M2 ratio of 3.6. Its genomic profile was characterized by 3p12.1-q25.31, 6p25.3, 8q23.1-q24.3, and 12p13.33-q24.33 gains, 6q22.31-q24.1 and 13q21.33-q34 losses, and 1p36.11-p35.3 copy neutral loss-of-heterozygosity. This profile was closer to nongerminal center B-cell DLBCL not-otherwise-specified, but with characteristic 3q, 12q, and 20p gains and lower 9p losses (P<0.05). We successfully verified array results using fluorescent DNA in situ hybridization on PLOD2, MYC, WNT1, and BCL2. Protein immunohistochemistry revealed that DLBCL expressed high IRF4 (6p25.3) and SELPLG (12q24.11) levels, intermediate TNFRSF14 (1p36.32; the exons 1 to 3 were unmutated), BTLA (3q13.2), PLOD2 (3q24), KLHL6 (3q27.1), and MYC (8q24.21) levels, and low AICDA (12p13.31) and EFNB2 (13q33.3) levels. The correlation between the DNA copy number and protein immunohistochemistry was confirmed for BTLA, PLOD2, and EFNB2. The characteristics of EBER versus EBER cases were similar, with the exception of specific changes: EBER cases had higher numbers of CD163 M2 macrophages and FOXP3 regulatory T lymphocytes, high programmed cell death 1 ligand 1 expression levels, slightly fewer genomic changes, and 3q and 4p focal gains. In conclusion, DLBCL has a characteristic genomic profile with 3q and 12 gains, 13q loss, different expression levels of relevant pathogenic biomarkers, and a microenvironment with high numbers of cytotoxic T lymphocytes and M2 macrophages.
29959183 Non-classical monocytes as mediators of tissue destruction in arthritis. 2018 Oct OBJECTIVES: Bone destruction in rheumatoid arthritis is mediated by osteoclasts (OC), which are derived from precursor cells of the myeloid lineage. The role of the two monocyte subsets, classical monocytes (expressing CD115, Ly6C and CCR2) and non-classical monocytes (which are CD115 positive, but low in Ly6C and CCR2), in serving as precursors for OC in arthritis is still elusive. METHODS: We investigated CCR2(-/-) mice, which lack circulating classical monocytes, crossed into hTNFtg mice for the extent of joint damage. We analysed monocyte subsets in hTNFtg and K/BxN serum transfer arthritis by flow cytometry. We sorted monocyte subsets and analysed their potential to differentiate into OC and their transcriptional response in response to RANKL by RNA sequencing. With these data, we performed a gene ontology enrichment analysis and gene set enrichment analysis. RESULTS: We show that in hTNFtg arthritis local bone erosion and OC generation are even enhanced in the absence of CCR2. We further show the numbers of non-classical monocytes in blood are elevated and are significantly correlated with histological signs of joint destruction. Sorted non-classical monocytes display an increased capacity to differentiate into OCs. This is associated with an increased expression of signal transduction components of RANK, most importantly TRAF6, leading to an increased responsiveness to RANKL. CONCLUSION: Therefore, non-classical monocytes are pivotal cells in arthritis tissue damage and a possible target for therapeutically intervention for the prevention of inflammatory joint damage.
30064915 Contribution of ancient human remains analysis to the understanding of the variability in 2018 Nov Genetic investigations on ancient human remains affected by rheumatological pathologies are a research field of particular interest for identifying the pathogenesis of diseases, especially those having an autoimmune background such as spondyloarthopaties (SpA). Reliable studies concerning this topic require collaboration between multiple disciplines, usually starting from paleopathologic observations up to molecular genetic screening. Here, we focused our investigation in a medieval necropolis in the Basque Country (13th-15th century, N = 163), which presents a high frequency of joint pathologies through two approaches: on the one hand, the analysis of joint manifestations for the differential diagnosis of the SpA and, on the other hand, the determination of the alleles of the HLA-B gene. The morphological analysis allowed determining that 30% of the individuals had rheumatic bone manifestations, with SpA being the most frequent (45%). The genetic analysis of individuals with and without pathologies, based on the study of the HLA-B gene, allowed finding 17 alleles for this gene, with HLA-B40, HLA-B27 and HLA-B35 being the most frequent. Although these alleles have been traditionally described as genetic markers associated to the development of SpA, in this study they were also found in individuals with other rheumatic diseases (osteoarthritis and rheumatoid arthritis) and even in individuals without pathologies. These data confirm the complexity of the relationship of the HLA-B gene variants with SpA, since it is not possible to establish a diagnosis of SpA with these variants alone. However, we suggest that allele HLA-B40, in combination with some specific rheumatic bone manifestations, facilitates the diagnosis of SpA.
29784872 SIRT1 inhibits rheumatoid arthritis fibroblast-like synoviocyte aggressiveness and inflamm 2018 Jun 29 Rheumatoid arthritis (RA) is an autoimmune disease of the joints characterized by synovial hyperplasia and chronic inflammation. Fibroblast-like synoviocytes (FLS) play a central role in RA initiation, progression, and perpetuation. Prior studies showed that sirtuin 1 (SIRT1), a deacetylase participating in a broad range of transcriptional and metabolic regulations, may impact cell proliferation and inflammatory responses. However, the role of SIRT1 in RA-FLS was unclear. Here, we explored the effects of SIRT1 on the aggressiveness and inflammatory responses of cultured RA-FLS. SIRT1 expression was significantly lower in synovial tissues and FLS from RA patients than from healthy controls. Overexpression of SIRT1 significantly inhibited RA-FLS proliferation, migration, and invasion. SIRT1 overexpression also significantly increased RA-FLS apoptosis and caspase-3 and -8 activity. Focusing on inflammatory phenotypes, we found SIRT1 significantly reduced RA-FLS secretion of TNF-α, IL-6, IL-8, and IL-1β. Mechanistic studies further revealed SIRT1 suppressed NF-κB pathway by reducing p65 protein expression, phosphorylation, and acetylation in RA-FLS. Our results suggest SIRT1 is a key regulator in RA pathogenesis by suppressing aggressive phenotypes and inflammatory response of FLS. Enhancing SIRT1 expression or function in FLS could be therapeutic beneficial for RA by inhibiting synovial hyperplasia and inflammation.
28937414 Rheumatoid arthritis and citrullination. 2018 Jan PURPOSE OF REVIEW: Dysregulated citrullination is a key element that drives the production and maintenance of antibodies to citrullinated proteins, a hallmark in rheumatoid arthritis (RA). This article reviews recent literature on the origin of citrullinated antigens in RA. RECENT FINDINGS: The study of synovial fluid from patients with RA has provided important insights into the identity of citrullinated proteins that accumulate in the RA joint (the RA citrullinome) and mechanisms that control their generation. SUMMARY: Citrullinating enzymes (peptidylarginine deiminases, PADs) are tightly controlled to limit their hyperactivation. Calcium and redox conditions are important regulators of PAD activity. Studies suggest that citrullination is dysregulated both intra- and extracellularly in RA. In neutrophils, host (i.e., perforin and the membrane attack complex) and bacterial (i.e., toxins) pore-forming proteins induce prominent calcium influx, cytolysis, and hyperactivation of PADs. These factors likely drive hypercitrullination in the RA joint and at extraarticular sites of disease initiation, respectively. As oxidizing conditions present in the extracellular environment are known to inactivate PADs, extracellular citrullination in RA probably requires the constant release of active enzymes from dying cells and may be accelerated by autoantibodies that activate PADs.
30593388 The importance of inhibition of a catabolic pathway of methotrexate metabolism in its effi 2019 Jan Methotrexate (MTX), an antifolate, is the anchor drug for the treatment of rheumatoid arthritis (RA). It is inexpensive, effective, and generally safe. When clinical response is inadequate, biological therapies are commonly used in combination with MTX. However, biological agents have safety concerns (i.e. infections, malignancy) and the addition of a biologic agent is expensive, making strategies to improve MTX efficacy important. Inhibition of pathways of folate metabolism involving purine metabolism by MTX, have been traditionally emphasized as important in MTX efficacy. However, inhibition MTX catabolism may also be important. MTX is irreversibly hydroxylated to form 7-hydroxy methotrexate (7-OH-MTX) by aldehyde oxidase (EC 1.2.3.1) (AOX). Catabolism of MTX to 7-OH-MTX is the first metabolic process imposed on an oral dose of MTX and will alter subsequent interactions of MTX with other enzymes. 7-OH-MTX is less potent than MTX in the treatment of rat adjuvant arthritis. RA patients with a low capacity to catabolize MTX to 7-OH-MTX do better clinically than individuals who are rapid formers of 7-OH-MTX. Therefore, altering the catabolism of MTX may be an innovative way to improve MTX efficacy. Raloxifene is a FDA-approved therapy for postmenopausal osteoporosis and for the reduction of invasive breast cancers but has no known activity in RA. Raloxifene is a potent inhibitor of human liver AOX. Postmenopausal women with RA frequently have low bone mineral density and would be candidates for raloxifene and MTX combination therapy. The effect of raloxifene on MTX metabolism has never been studied. Our hypothesis is that in postmenopausal women with RA and osteoporosis treated with MTX and raloxifene, the inhibition of AOX with resultant decreased formation of 7-OH MTX; will increase MTX levels and improve MTX efficacy. This hypothesis could be studied in an open-label, proof of concept clinical study in individuals before and after the addition of raloxifene. Red blood cell MTX and 7-OH-MTX levels and RA disease activity (DAS28) would be measured. In possible future studies, there are dietary substances, as supplements, (e.g. epigallocatechin gallate in green tea and resveratrol) which inhibit human liver AOX which could be evaluated.