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ID PMID Title PublicationDate abstract
31131543 IL-7R gene polymorphisms among patients with rheumatoid arthritis: A case-control study. 2019 Jul BACKGROUND: Rheumatoid arthritis (RA) is the most common inflammatory disease which refers to bony erosions and joint destruction largely caused by genetic factors. Our study aimed to explore whether interleukin-7 receptor (IL-7R) gene polymorphisms influenced RA risk in the Han Chinese population. METHODS: Five single nucleotide polymorphisms (SNPs) in IL-7R gene were successfully genotyped using Agena MassARRAY platform. The associations between IL-7R polymorphisms and RA were evaluated by the Chi-squared test, T test, genetic model analysis, and haplotype analysis. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) using logistic regression analysis. RESULTS: Rs969129 and rs6451231 in the IL-7R gene were associated with an increased risk of RA in the allele model (OR = 1.25, 95% CI = 1.05-1.49, p = 0.013; OR = 1.23, 95% CI = 1.03-1.48, p = 0.023), respectively. In the genetic models, rs969129 and rs6451231 were associated with an increased risk of RA. After stratification analysis by age, rs969129 and rs6451231 were associated with an increased risk of RA in patients (age <54). After stratification analysis by gender, rs6451231 was associated with an increased risk of RA in males, while rs969129 was found to be associated with an elevated risk of RA in females. And there was a strong linkage disequilibrium among the four SNPs (rs969129, rs118137916, rs10053847, and rs6451231). CONCLUSION: These results suggested rs969129 and rs6451231 in the IL-7R gene were associated with an increased risk of RA in the Han Chinese population.
31607368 Origin and function of synovial macrophage subsets during inflammatory joint disease. 2019 Mononuclear phagocytes, including monocytes and macrophages, are a central component of the host's innate immune system designated to protect against invading pathogens. However, these cells do not only interact with various parts of the innate and adaptive immune system, but also fulfill indispensable duties during the control of tissue homeostasis and organ function. Moreover, macrophages are crucially involved in tissue remodeling and repair in response to damage. Simultaneously, mononuclear phagocytes might also contribute to the pathogenesis of various inflammatory and autoimmune diseases. In particular, their potential role in inflammatory joint diseases such as rheumatoid arthritis (RA) has drawn increasing attention and substantially shaped our general understanding of the role of monocytes and macrophages during health and disease. This review summarizes our current knowledge about the origin and function of mononuclear phagocytes within the joint and addresses their involvement in joint inflammation.
31648940 Association between HTLV-1 infection and adverse health outcomes: a systematic review and 2020 Jan BACKGROUND: Human T-cell lymphotropic virus type 1 (HTLV-1) is a human retrovirus that causes a lifelong infection. Several diseases, including an aggressive form of leukaemia, have been designated as associated with HTLV-1, whereby having HTLV-1 is a necessary condition for diagnosis. Beyond these diseases, there is uncertainty about other health effects of HTLV-1. We aimed to synthesise evidence from epidemiological studies on associations between health outcomes and HTLV-1. METHODS: For this systematic review and meta-analysis, we searched Embase, MEDLINE, MEDLINE In-Process, and Global Health for publications from their inception to July, 2018. We included cohort, case-control, and controlled cross-sectional studies that compared mortality or morbidity between people with and without HTLV-1. We excluded studies of psychiatric conditions, of symptoms or clinical findings only, of people who had undergone blood transfusion or organ transplant, and of population groups defined by a behavioural characteristic putting them at increased risk of co-infection with another virus. We extracted the risk estimates (relative risks [RRs] or odds ratios [ORs]) that reflected the greatest degree of control for potential confounders. We did a random-effects meta-analysis for groups of effect estimates where case ascertainment methods, age groups, and confounders were similar, presenting pooled estimates with 95% CIs and prediction intervals. FINDINGS: Of the 3318 identified studies, 39 met the inclusion criteria, examining 42 clinical conditions between them. The adjusted risk of death due to any cause was higher in people with HTLV-1 when compared with HTLV-1-negative counterparts (RR 1·57, 95% CI 1·37-1·80). From meta-analysis, HTLV-1 was associated with increased odds of seborrheic dermatitis (OR 3·95, 95% CI 1·99-7·81), Sjogren's syndrome (3·25, 1·85-5·70), and, inversely, with lower relative risk of gastric cancer (RR 0·45, 0·28-0·71). There were a further 14 diseases with significant associations or substantially elevated risk with HTLV-1 from single studies (eczema [children]; bronchiectasis, bronchitis and bronchiolitis [analysed together]; asthma [males]; fibromyalgia; rheumatoid arthritis; arthritis; tuberculosis; kidney and bladder infections; dermatophytosis; community acquired pneumonia; strongyloides hyperinfection syndrome; liver cancer; lymphoma other than adult T-cell leukaemia-lymphoma; and cervical cancer). INTERPRETATION: There is a broad range of diseases studied in association with HTLV-1. However, the elevated risk for death among people with HTLV-1 is not explained by available studies of morbidity. Many of the diseases shown to be associated with HTLV-1 are not fatal, and those that are (eg, leukaemia) occur too rarely to account for the observed mortality effect. There are substantial research gaps in relation to HTLV-1 and cardiovascular, cerebrovascular, and metabolic disease. The burden of disease associated with the virus might be broader than generally recognised. FUNDING: Commonwealth Department of Health, Australia.
31320744 Overweight/obesity affects histological features and inflammatory gene signature of synovi 2019 Jul 18 Overweight/obesity influence disease burden and clinical outcome of Rheumatoid Arthritis (RA). The impact of overweight/obesity on synovial tissue (ST) inflammation is largely unknown. Here, we investigated the histological and transcriptional signature of ST obtained from RA in different disease phases (disease onset, failure to first-line conventional DMARDs and in sustained clinical and ultrasound remission) finding that overweight/obese DMARDs naive RA showed higher likelihood of follicular synovitis, higher IHC scores for sublining inflammatory cells (CD68(+), CD21(+) and CD20(+)) and higher IL-1RA plasma levels than normal weight RA. Regardless to the synovitis pattern, overweight/obese DMARDs naive RA showed a worse clinical response to "Treat-to-target" (T2T) than normal weight RA at 6 and 12 months follow-up. Conversely, MTX-IR RA did not show significant differences in synovial inflammation based on BMI category. Overweight/obese RA in stable clinical and US remission showed higher degree of residual synovitis in terms of sublining CD68(+), CD20(+) cells and lining and sublining CD3(+) compared to normal weight RA. Finally, gene expression profile analysis revealed that ST of overweight/obese DMARDs naive RA is enriched by CCL3 and MyD88 compared to normal weight RA in sustained disease remission, the latter correlating with BMI and IHC scores for synovial CD68(+) cells. These findings suggest that indeed overweight/obese RA show higher degree of synovitis at disease onset and after remission achievement that influences the response rate to T2T and should be considered within the management of patients with RA.
31267570 Increased risk of developing Crohn's disease or ulcerative colitis in 17 018 patients whi 2019 Aug BACKGROUND: Anti-TNFα agents have revolutionised management of chronic inflammatory diseases. Paradoxically, these agents might provoke development of de novo autoimmune diseases. AIM: To examine whether there is an increased risk of developing Crohn's disease (CD) and ulcerative colitis (UC) while under treatment with anti-TNFα agents for diseases other than inflammatory bowel disease (IBD) METHODS: A nationwide cohort study, based on Danish health registries, of all patients who utilised anti-TNFα agents for non-IBD indications. Included were patients, who had diseases for which anti-TNFα agent is indicated (rheumatoid arthritis, psoriasis/psoriatic arthritis, ankylosing spondylitis, others). The observation period for development of de novo IBD started from 2004. Exposed patients had received at least one dose of anti-TNFα. RESULTS: In total 17 018 individuals with autoimmune diseases were exposed to anti-TNFα (the vast majority had infliximab, etanercept and adalimumab), and 63 308 individuals were not. Patients treated with etanercept had an increased risk of being diagnosed with CD and UC while under treatment, adjusted hazard ratio 2.0 [95% CI: 1.4-2.8] and 2.0 [95% CI: 1.5-2.8], respectively. The corresponding hazards ratios for infliximab were 1.3 [95% CI: 0.8-2.2] and 1.0 [95% CI:0.6-1.6], and for adalimumab 1.2 [95% CI: 0.8-1.8] and 0.6 [95% CI: 0.3-1.0]. CONCLUSIONS: Patients treated for autoimmune diseases with anti-TNFα had an increased risk of being diagnosed with CD or UC while under treatment with etanercept. The nature of this association is uncertain. This finding has relevance to clinical care and insights into common mechanisms of the pathophysiology of these diseases.
30184197 Burden for Parents of Patients With Schizophrenia-A Nationwide Comparative Study of Parent 2019 Jun 18 BACKGROUND: The study aimed to (1) compare the risk of health care use, adverse health status, and work productivity loss of parents of patients with schizophrenia to parents of patients with multiple sclerosis (MS), rheumatoid arthritis (RA), epilepsy, and healthy controls; and (2) evaluate such outcome measures while considering disease severity of schizophrenia. METHODS: Based on linkage of Swedish registers, at least one parent was included (n = 18215) of patients with schizophrenia (information 2006-2013, n = 10883). Similarly, parental information was linked to patients with MS, RA, epilepsy, and matched healthy controls, comprising 11292, 15516, 34715, and 18408 parents, respectively. Disease severity of schizophrenia was analyzed. Different regression models yielding odds ratios (OR), hazard ratios (HR), or relative risks (RR) with 95% confidence intervals (CI) were run. RESULTS: Psychiatric health care use, mainly due to anxiety and affective disorders, showed a strongly increasing trend for parents of patients with schizophrenia throughout the observation period. During the follow-up, these parents had an up to 2.7 times higher risk of specialized psychiatric health care and receipt of social welfare benefits than other parents. Parents of the moderately severely ill patients with schizophrenia had higher risk estimates for psychiatric health care (RR: 1.12; 95% CI: 1.07-1.17) compared with parents of least severely ill patients. CONCLUSIONS: Parents of patients with schizophrenia have a considerably higher risk of psychiatric health care and social welfare benefit receipt than other parents. Psychiatric health care use worsens over time and with increasing disease severity of the offspring.
30474154 Estimating cross-population genetic correlations of causal effect sizes. 2019 Mar Recent studies have examined the genetic correlations of single-nucleotide polymorphism (SNP) effect sizes across pairs of populations to better understand the genetic architectures of complex traits. These studies have estimated ρ g , the cross-population correlation of joint-fit effect sizes at genotyped SNPs. However, the value of ρ g depends both on the cross-population correlation of true causal effect sizes ( ρ b ) and on the similarity in linkage disequilibrium (LD) patterns in the two populations, which drive tagging effects. Here, we derive the value of the ratio ρ g / ρ b as a function of LD in each population. By applying existing methods to obtain estimates of ρ g , we can use this ratio to estimate ρ b . Our estimates of ρ b were equal to 0.55 ( SE = 0.14) between Europeans and East Asians averaged across nine traits in the Genetic Epidemiology Research on Adult Health and Aging data set, 0.54 ( SE = 0.18) between Europeans and South Asians averaged across 13 traits in the UK Biobank data set, and 0.48 ( SE = 0.06) and 0.65 ( SE = 0.09) between Europeans and East Asians in summary statistic data sets for type 2 diabetes and rheumatoid arthritis, respectively. These results implicate substantially different causal genetic architectures across continental populations.
30845214 A novel nonsense variant in SUPT20H gene associated with Rheumatoid Arthritis identified b 2019 The triggering and development of Rheumatoid Arthritis (RA) is conditioned by environmental and genetic factors. Despite the identification of more than one hundred genetic variants associated with the disease, not all the cases can be explained. Here, we performed Whole Exome Sequencing in 9 multiplex families (N = 30) to identify rare variants susceptible to play a role in the disease pathogenesis. We pre-selected 77 genes which carried rare variants with a complete segregation with RA in the studied families. Follow-up linkage and association analyses with pVAAST highlighted significant RA association of 43 genes (p-value < 0.05 after 106 permutations) and pinpointed their most likely causal variant. We re-sequenced the 10 most significant likely causal variants (p-value ≤ 3.78*10-3 after 106 permutations) in the extended pedigrees and 9 additional multiplex families (N = 110). Only one SNV in SUPT20H: c.73A>T (p.Lys25*), presented a complete segregation with RA in an extended pedigree with early-onset cases. In summary, we identified in this study a new variant associated with RA in SUPT20H gene. This gene belongs to several biological pathways like macro-autophagy and monocyte/macrophage differentiation, which contribute to RA pathogenesis. In addition, these results showed that analyzing rare variants using a family-based approach is a strategy that allows to identify RA risk loci, even with a small dataset.
31203157 BMP9 inhibits the proliferation and migration of fibroblast-like synoviocytes in rheumatoi 2019 Sep Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease; its pathogenesis remains unclear. Fibroblast-like synoviocytes (FLSs) play a vital role in the pathogenesis of RA. BMP9, a member of the bone morphogenetic protein (BMP) family, has been reported to play a critical role in both normal physiological processes and the pathology of various diseases. In this study, we explored the function and underlying mechanisms of BMP9 in the proliferation and migration of RA FLSs. We found that BMP9 expression was significantly downregulated in the synovial tissues of RA patients, compared with those of OA patients; BMP9 expression was also low in adjuvant-induced arthritis (AA) samples. Additionally, inhibition of BMP9 expression by BMP9 siRNA increased the proliferation of AA FLSs, and the expression of c-Myc, Cyclin D1, MMP-2, and MMP-9, but not TIMP-1, in AA FLSs. However, AA FLSs transfected with the overexpression vector PEX-3-BMP9 showed reduced proliferation and expression of c-Myc, Cyclin D1, MMP-2, and MMP-9, but not TIMP-1. Further studies indicate that BMP9 may induce the activation of the PI3K/AKT signaling pathway. Thus, these data indicate that BMP9 may play a critical role in the proliferation and migration of FLSs through the activation of the AKT signaling pathway.
30615240 EBV-positive mucocutaneous ulcer arising in rheumatoid arthritis patients treated with met 2019 Jan Methotrexate (MTX) is currently used as first-line anchor drug for rheumatoid arthritis (RA). Therefore, the number of MTX-associated lymphoproliferative disorders, including Epstein-Barr virus-positive mucocutaneous ulcer (EBVMCU), has increased. Some aspects of MTX-associated EBVMCU (MTX-EBVMCU), particularly clinical behavior and treatment for RA after MTX cessation, have not been well described. Herein, we report nine cases of MTX-EBVMCU with clinical information regarding RA. Seven of nine patients showed spontaneous regression (SR) after immunosuppressive (IS) cessation. The other two required cytotoxic chemotherapy. Eventually, all achieved complete remission. No patients experienced EBVMCU relapse. Eight patients had RA flare after IS cessation. To control the RA activity, rituximab was administered to three patients. The remaining patients were treated by other agents. Regarding the RA activity, all were in the status of low disease activity or clinical remission. In conclusion, MTX-associated EBVMCU has an indolent clinical course and SR after IS cessation can be expected. After the withdrawal of MTX, the majority of patients experience RA flare and required treatment. In our series, RA was well controlled without reinitiating MTX. Therefore, to prevent the EBVMCU relapse, it might be advisable to avoid MTX reintroduction, and rituximab might be the more preferable agent for RA treatment.
31146626 Low frequency of septic arthritis after arthrocentesis and intra-articular glucocorticoid 2019 Sep Objective: The aim of this study was to evaluate the risk of septic arthritis (SA) in patients who received an intra-articular (IA) glucocorticoid (GC) injection and to describe the characteristics of these patients. Methods: All patients undergoing IA procedures at the orthopaedic and rheumatological departments on the Danish island of Funen from January 2006 to December 2013 were identified in the central database and included by register extraction. Patients who developed a clinically inflamed joint and positive synovial fluid culture within 14 days after IA GC injection were considered as having SA. Retrospectively, data on age, gender, affected joint location, bacterial agent, pre-existing inflammatory disorder, and death within 30 days were extracted from the patient files. According to local recommendations, a non-touch sterile technique was used for IA procedures. Patients were informed about the risk of SA and advised to seek medical attention on suspicion of infection or lack of improvement. Results: In total, 22 370 IA procedures were performed. Among these, 14 118 GC injections and 8252 arthrocenteses were undertaken. Only 11 patients were diagnosed with SA (0.08%, 95% confidence interval 0.03-0.12). Risk factors for SA were male gender, age, and pre-existing joint disease. Conclusion: We found a low frequency of SA subsequent to IA GC injections. Older patients with pre-existing joint disease are at higher risk of developing SA.
30612115 Risk of serious infections in patients with rheumatoid arthritis treated in routine care w 2019 Mar OBJECTIVE: To estimate (1) crude and age-and gender-adjusted incidence rates (IRs) of serious infections (SI) and (2) relative risks (RR) of SI in patients with rheumatoid arthritis (RA) initiating treatment with abatacept, rituximab or tocilizumab in routine care. METHODS: This is an observational cohort study conducted in parallel in Denmark and Sweden including patients with RA in Denmark (DANBIO) and Sweden (Anti-Rheumatic Treatment in Sweden Register/Swedish Rheumatology Quality Register) who started abatacept/rituximab/tocilizumab in 2010-2015. Patients could contribute to more than one treatment course. Incident SI (hospitalisations listing infection) and potential confounders were identified through linkage to national registries. Age- and gender-adjusted IRs of SI per 100 person years and additionally adjusted RRs of SI during 0-12 and 0-24 months since start of treatment were assessed (Poisson regression). Country-specific RRs were pooled using inverse variance weighting. RESULTS: We identified 8987 treatment courses (abatacept: 2725; rituximab: 3363; tocilizumab: 2899). At treatment start, rituximab-treated patients were older, had longer disease duration and more previous malignancies; tocilizumab-treated patients had higher C reactive protein. During 0-12 and 0-24 months of follow-up, 456 and 639 SI events were identified, respectively. The following were the age- and gender-adjusted 12-month IRs for abatacept/rituximab/tocilizumab: 7.1/8.1/6.1 for Denmark and 6.0/6.4/4.7 for Sweden. The 24-month IRs were 6.1/7.5/5.2 for Denmark and 5.6/5.8/4.3 for Sweden. Adjusted 12-month RRs for tocilizumab versus rituximab were 0.82 (0.50 to 1.36) for Denmark and 0.76 (0.57 to 1.02) for Sweden, pooled 0.78 (0.61 to 1.01); for abatacept versus rituximab 0.94 (0.55 to 1.60) for Denmark and 0.86 (0.66 to 1.13) for Sweden, pooled 0.88 (0.69 to 1.12); and for abatacept versus tocilizumab 1.15 (0.69 to 1.90) for Denmark and 1.14 (0.83 to 1.55) for Sweden, pooled 1.13 (0.91 to 1.42). The adjusted RRs for 0-24 months were similar. CONCLUSION: For patients starting abatacept, rituximab or tocilizumab, differences in baseline characteristics were seen. Numerical differences in IR of SI between drugs were observed. RRs seemed to vary with drug (tocilizumab < abatacept < rituximab) but should be interpreted with caution due to few events and risk of residual confounding.
29973648 The chemokine receptor CCR7 is a promising target for rheumatoid arthritis therapy. 2019 Oct The chemokine receptor CCR7 and its ligands CCL19 and CCL21 guide the homing and positioning of dendritic and T cells in lymphoid organs, thereby contributing to several aspects of adaptive immunity and immune tolerance. In the present study, we investigated the role of CCR7 in the pathogenesis of collagen-induced arthritis (CIA). By using a novel anti-human CCR7 antibody and humanized CCR7 mice, we evaluated CCR7 as a target in this autoimmune model of rheumatoid arthritis (RA). Ccr7-deficient mice were completely resistant to CIA and presented severely impaired antibody responses to collagen II (CII). Selective CCR7 expression on dendritic cells restored arthritis severity and anti-CII antibody titers. Prophylactic and therapeutic treatment of humanized CCR7 mice with anti-human CCR7 mAb 8H3-16A12 led to complete resistance to CIA and halted CIA progression, respectively. Our data demonstrate that CCR7 signaling is essential for the induction of CIA and identify CCR7 as a potential therapeutic target in RA.
31386311 Exosomal long noncoding RNAs in aging and age-related diseases. 2019 Dec Molecules secreted by cells into the internal environment during aging, including those secreted in exosomes, have long been a matter of concern. Those cells that absorb exosomes, also known as recipient cells, exhibit certain phenotypic changes because of the regulatory role of functional molecules (including proteins and nucleic acids) released in exosomes. Involvement of noncoding RNAs (ncRNAs) in the regulation of aging has received increasing attention, and long ncRNAs (lncRNAs) have become one of the research hotspots in recent years. LncRNAs carried by exosomes play a role in intercellular communication between adjacent and distant cells. Moreover, exosomal lncRNAs promote the decline of organ functions and the development of age-related diseases, including atherosclerosis, Type 2 diabetes, osteoporosis, osteoarthritis, rheumatoid arthritis, Parkinson's disease, multiple sclerosis, and cancer. Here, we review the regulatory roles of exosomal lncRNAs in aging and age-related diseases.
30802366 Activation of the Peroxisome Proliferator-Activated Receptor γ Coactivator 1β/NFATc1 Pat 2019 Aug OBJECTIVE: Activation of osteoclastogenesis at the bone site in rheumatoid arthritis (RA) is well established. The mechanisms by which circulating osteoclast precursors contribute are still unclear. Peroxisome proliferator-activated receptor γ coactivator 1β (PGC-1β) is implicated in transcriptional regulation of osteoclastogenesis in mouse models. This study was undertaken to investigate the contribution of PGC-1β to circulating osteoclast precursors and its link to bone destruction in RA. METHODS: PGC-1β expression in RA peripheral blood CD14+ monocytes was increased and showed correlation with joint destruction shown on radiographs. Cells from RA patients or healthy controls were transfected with a lentivirus vector for PGC-1β gene silencing or overexpression and cultured with macrophage colony-stimulating factor and RANKL. Bone resorption activity, bone-degrading enzymes, and signaling molecules were measured in these mature osteoclasts. RESULTS: Increased nuclear accumulation of PGC-1β was observed in RA peripheral blood CD14+ monocytes, and these cells had stronger osteoclastogenesis than in healthy controls. PGC-1β protein expression was positively correlated with radiographic joint destruction (r = 0.396-0.413; all P < 0.05). PGC-1β knockdown suppressed (51-82% reduction) the expression of cathepsin K, tartrate-resistant acid phosphatase (TRAP), and matrix metalloproteinase 9 (MMP-9), as well as osteoclast differentiation and bone resorption activity. Conversely, PGC-1β overexpression increased these markers (by 1.5-1.8-fold) and osteoclastogenesis. VIVIT, an inhibitor of NFATc1 activation, inhibited the effect of overexpressed PGC-1β by reducing cathepsin K, TRAP, and MMP-9 expression. Chromatin immunoprecipitation assay and dual-luciferase reporter gene assay showed PGC-1β bound to NFATc1 promoter, leading to transcriptional activation. CONCLUSION: Activation of the PGC-1β/NFATc1 pathway in circulating osteoclast precursors was associated with bone destruction in RA. This may represent a new treatment target.
31526674 Repeat exchange transfusion for treatment of severe babesiosis. 2019 Oct We report a case of severe babesiosis presenting with 43% parasitemia in a 73-year-old splenectomized woman on etanercept for rheumatoid arthritis. She initially was treated aggressively with clindamycin and quinine and exchange transfusion. Despite a post-exchange drop in parasitemia to 7.6%, it rebounded to 11.4% on hospital day 5 accompanied by new onset high fevers and hypoxia. She improved after a second exchange transfusion and ultimately resolved her infection after 12 weeks of antibabesial antibiotics. Although exchange transfusion is commonly used in immunocompromised hosts, there is a dearth of information about repeat exchange transfusion, including the risk for and outcome of repeat exchange. We performed a literature search for other cases of repeat exchange transfusion for severe Babesia microti infection and compared our case with those in other published reports.
30876808 Interactions between cadherin-11 and platelet-derived growth factor receptor-alpha signali 2019 Jun 1 Cadherins are homophilic cell-to-cell adhesion molecules that help cells respond to environmental changes. Newly formed cadherin junctions are associated with increased cell phosphorylation, but the pathways driving this signaling response are largely unknown. Since cadherins have no intrinsic signaling activity, this phosphorylation must occur through interactions with other signaling molecules. We previously reported that cadherin-11 engagement activates joint synovial fibroblasts, promoting inflammatory and degradative pathways important in rheumatoid arthritis (RA) pathogenesis. Our objective in this study was to discover interacting partners that mediate cadherin-11 signaling. Protein array screening showed that cadherin-11 extracellular binding domains linked to an Fc domain (cad11Fc) induced platelet-derived growth factor (PDGFR)-α phosphorylation in synovial fibroblasts and glioblastoma cells. PDGFRs are growth factor receptor tyrosine kinases that promote cell proliferation, survival, and migration in mesodermally derived cells. Increased PDGFR activity is implicated in RA pathology and associates with poor prognosis in several cancers, including sarcoma and glioblastoma. PDGFRα activation by cadherin-11 signaling promoted fibroblast proliferation, a signaling pathway independent from cadherin-11-stimulated IL-6 or matrix metalloproteinase (MMP)-3 release. PDGFRα phosphorylation mediated most of the cad11Fc-induced phosphatidyl-3-kinase (PI3K)/Akt activation, but only part of the mitogen-activated protein kinase (MAPK) response. PDGFRα-dependent signaling did not require cell cadherin-11 expression. Rather, cad11Fc immunoprecipitated PDGFRα, indicating a direct interaction between cadherin-11 and PDGFRα extracellular domains. This study is the first to report an interaction between cadherin-11 and PDGFRα and adds to our growing understanding that cadherin-growth factor receptor interactions help balance the interplay between tissue growth and adhesion.
30465880 Neuraxial TNF and IFN-beta co-modulate persistent allodynia in arthritic mice. 2019 Feb In rheumatoid arthritis, joint pain can persist despite resolution of swelling. Similarly, in the murine K/BxN serum transfer model, a persistent tactile allodynia is observed after the resolution of joint inflammation (post-inflammatory pain) in male mice. Here, we found female wild type (WT) mice show inflammatory, but reduced post-inflammatory tactile allodynia. The transition to the post-inflammatory phenotype is dependent on TLR4 signaling. At the spinal level, we found differences in TNF and IFNβ mRNA expression in WT and TLR4 deficient males. In wild type male and female mice, there is differential temporal spinal expression of TNF and IFNβ. In WT males, blockade of TNF or administration of IFNβ was insufficient to affect the persistent allodynia. However, co-administration of intrathecal (IT) IFNβ and anti-TNF antibodies in male WT mice permanently reversed tactile allodynia. IT IFNβ treatment induces expression of anti-inflammatory proteins, contributing to the beneficial effect. Together, these experiments illustrated differences in the transition to chronic tactile allodynia in male and female animals and the complexities of effective pharmacologic interventions.
30883553 The effects of laser acupuncture on the modulation of cartilage extracellular matrix macro 2019 OBJECTIVES: Articular cartilage damage related to irreversible physical disability affects most patients with chronic rheumatoid arthritis (RA). Strategies targeting the preservation of cartilage function are needed. Laser acupuncture (LA) can be an emerging alternative therapy for RA; however, its molecular mechanism underlying the beneficial effect on cartilage has not been elucidated. This study aimed to examine the potential chondroprotective effects of LA on extracellular matrix (ECM) macromolecules and proinflammatory cytokines in the articular cartilage of adjuvant-induced arthritis (AIA) rats and explore its related mechanisms. DESIGN: Monoarthritis was induced in adult male Sprague-Dawley rats (250-300 g) via intraarticular injection of complete Freund's adjuvant (CFA) into the tibiotarsal joint. Animals were treated with LA at BL60 and KI3 acupoints three days after CFA administration with a 780 nm GaAlAs laser at 15 J/cm2 daily for ten days. The main outcome measures including paw circumference, paw withdrawal threshold, histopathology and immunoassays of tumor necrosis factor-α (TNF-α), collagen type II (CoII), cartilage oligomeric matrix protein (COMP) were analyzed. RESULTS: LA significantly reduced ankle edema and inflammation-induced hyperalgesia in AIA rats (P < 0.05). Moreover, the TNF-α levels were significantly decreased while CoII, COMP and proteoglycans proteins were significantly enhanced following LA stimulation of the AIA cartilage compared to those treated with sham-LA (P < 0.05). CONCLUSIONS: LA attenuates cartilage degradation in AIA rat by suppressing TNF-α activation and up-regulating ECM macromolecules, suggesting LA might be of potential clinical interest in RA treatment.
31376624 Rhein inhibits ATP-triggered inflammatory responses in rheumatoid rat fibroblast-like syno 2019 Oct Rheumatoid arthritis (RA) is a chronic and systemic inflammatory disorder, which may lead to joint disabilities. So far the pathogenesis of RA remains largely undetermined, and there are still no potent drugs for clinical treatment. Rhein, a natural bioactive anthraquinone derivative, exhibited significant anti-inflammatory activities demonstrated by previous studies. Here we aimed to investigate the effects of rhein on ATP-induced inflammation responses in fibroblast-like synoviocytes isolated from a rat model of collagen induced arthritis (CIA). Our results showed that ATP triggered rapid cytosolic calcium concentration ([Ca(2+)](c)) increase depending on extracellular Ca(2+) entry. Given the major P2 subtypes expressed in rat synoviocytes were P2X(4) and P2Y(2) receptors, ATP-elicited calcium entry should be mainly resulted from activating P2X(4). Interestingly, rhein could effectively block the ATP-induced [Ca(2+)](c) increases in a dose-dependent manner. Besides, rhein also suppressed the production of intracellular reactive oxygen species (ROS) induced by ATP in synoviocytes that was resulted from P2X(4)-mediated Ca(2+) entry. Brilliant blue G (BBG), which can block P2X(4) receptor at high concentration, showed similar suppressive effects on above responses. Furthermore, in lipopolysaccharide-primed cells, application of ATP synergistically promoted the gene expression of cyclooxygenase-2, interleukin-6 and matrix metalloproteinase-9. Both rhein and BBG attenuated these inflammatory gene expressions enhanced by ATP. Above data together suggested a potential anti-arthritic role of rhein by inhibiting ATP-induced [Ca(2+)](c) increase, ROS production and inflammatory gene expression targeting P2X(4) in CIA rat synoviocytes, which will provide a novel insight in the therapy of RA.