Macrophage-derived mir-100-5p orchestrates synovial proliferation and inflammation in rheumatoid arthritis through mTOR signaling.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by synovial inflammation, causing substantial disability and reducing life quality. While macrophages are widely appreciated as a master regulator in the inflammatory response of RA, the precise mechanisms underlying the regulation of proliferation and inflammation in RA-derived fibroblast-like synoviocytes (RA-FLS) remain elusive. Here, we provide extensive evidence to demonstrate that macrophage contributes to RA microenvironment remodeling by extracellular vesicles (sEVs) and downstream miR-100-5p/ mammalian target of rapamycin (mTOR) axis. RESULTS: We showed that bone marrow derived macrophage (BMDM) derived-sEVs (BMDM-sEVs) from collagen-induced arthritis (CIA) mice (cBMDM-sEVs) exhibited a notable increase in abundance compared with BMDM-sEVs from normal mice (nBMDM-sEVs). cBMDM-sEVs induced significant RA-FLS proliferation and potent inflammatory responses. Mechanistically, decreased levels of miR-100-5p were detected in cBMDM-sEVs compared with nBMDM-sEVs. miR-100-5p overexpression ameliorated RA-FLS proliferation and inflammation by targeting the mTOR pathway. Partial attenuation of the inflammatory effects induced by cBMDM-sEVs on RA-FLS was achieved through the introduction of an overexpression of miR-100-5p. CONCLUSIONS: Our work reveals the critical role of macrophages in exacerbating RA by facilitating the transfer of miR-100-5p-deficient sEVs to RA-FLS, and sheds light on novel disease mechanisms and provides potential therapeutic targets for RA interventions.

Repurposed drug agomelatine is therapeutic against collagen-induced arthritis via iNOS targeting.

BACKGROUND: The most promising biologics tumor necrosis factor α (TNFα) inhibitors are effective in treating rheumatoid arthritis (RA) in only 50-70 % of the cases; thus, new drugs targeting TNFα-mediated inflammation are required. METHODS: Firstly, the drugs that could inhibit FLS proliferation and TNFα induced inflammatory cytokine production were screened. Secondly, treatment effects of the identified drugs were screened in collagen-induced arthritis (CIA) mouse model. Thirdly, the inhibitory effect of the identified drug, agomelatine (AOM), on TNFα induced inflammatory cytokine production and NF-κB activity were confirmed. Fourthly, bioinformatics was applied to predict the binding target of AOM and the binding was confirmed, and the already known inhibitor of target was used to test the treatment effect for CIA mouse model. Finally, the effect of AOM on signaling pathway was tested and on TNFα induced inflammatory cytokine production was observed after inhibiting the target. RESULTS: AOM effectively inhibited TNFα-induced NF-κB activation, NF-κB p65 translocation, and inflammatory cytokines production in vitro and was therapeutic against CIA. The mechanistic study indicated inducible nitric oxide synthase (iNOS) as the binding target of AOM. 1400 W, a known inhibitor of iNOS, could effectively treat CIA by decreasing iNOS activity and the levels of inflammatory cytokines. The inhibitory effect of AOM on TNFα-induced inflammation was further elucidated by 1400 W, or NF-κB p65 inhibitor JSH-23, indicating that AOM is therapeutic against CIA via iNOS/ERK/p65 signaling pathway after binding with iNOS. CONCLUSIONS: AOM is therapeutic against CIA via inhibition of the iNOS/ERK/p65 signaling pathway after binding with iNOS.

Targeting glycolytic pathway in fibroblast-like synoviocytes for rheumatoid arthritis therapy: challenges and opportunities.

INTRODUCTION: Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by hyperplastic synovium, pannus formation, immune cell infiltration, and potential articular cartilage damage. Notably, fibroblast-like synoviocytes (FLS), especially rheumatoid arthritis fibroblast-like synoviocytes (RAFLS), exhibit specific overexpression of glycolytic enzymes, resulting in heightened glycolysis. This elevated glycolysis serves to generate ATP and plays a pivotal role in immune regulation, angiogenesis, and adaptation to hypoxia. Key glycolytic enzymes, such as hexokinase 2 (HK2), phosphofructose-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), and pyruvate kinase M2 (PKM2), significantly contribute to the pathogenic behavior of RAFLS. This increased glycolysis activity is regulated by various signaling pathways. MATERIALS AND METHODS: A comprehensive literature search was conducted to retrieve relevant studies published from January 1, 2010, to the present, focusing on RAFLS glycolysis, RA pathogenesis, glycolytic regulation pathways, and small-molecule drugs targeting glycolysis. CONCLUSION: This review provides a thorough exploration of the pathological and physiological characteristics of three crucial glycolytic enzymes in RA. It delves into their putative regulatory mechanisms, shedding light on their significance in RAFLS. Furthermore, the review offers an up-to-date overview of emerging small-molecule candidate drugs designed to target these glycolytic enzymes and the upstream signaling pathways that regulate them. By enhancing our understanding of the pathogenic mechanisms of RA and highlighting the pivotal role of glycolytic enzymes, this study contributes to the development of innovative anti-rheumatic therapies.

Fexofenadine protects against lipopolysaccharide-induced acute lung injury by targeting cytosolic phospholipase A2.

OBJECTIVE: Acute lung injury (ALI) causes acute respiratory distress syndrome, with a high mortality rate of 40%, with currently available pharmacological treatments. Cytosolic phospholipase A2 (cPLA2) plays a critical role in the lipopolysaccharide (LPS)-induced pathology of ALI. This study assessed the therapeutic effects of fexofenadine (FFD), an on-market small-molecule drug that can target cPLA2 in LPS-induced ALI. METHODS: Primary macrophages obtained from the bone marrow of wild-type and cPLA2 knockout mice and the alveolar macrophage cell line, MHS were used to test the inhibitory effect of FFD on the cPLA2/ERK/p65 signaling pathway, NF-κB p65 translocation, and cytokine and chemokine production. An LPS-induced ALI mouse model was used to assess the treatment effects of FFD. Flow cytometry detected subsets of macrophages and neutrophils. cPLA2 activity and downstream hydrolysates were detected. Treatment with a cPLA2 inhibitor or NF-κB p65 inhibitor confirmed that FFD functioned through the cPLA2/ERK/p65 signaling pathway by targeting cPLA2. RESULTS: FFD reduced the infiltration of macrophages and neutrophils, decreased the protein secretion in bronchoalveolar lavage fluid, and reduced the production of TNFα, IL-1ß, IL-6, MCP-1, and IL-8 in the lung, bronchoalveolar lavage fluid, and sera of LPS-induced ALI mice. FFD inhibited cPLA2 activity, suppressed the cPLA2/ERK/p65 signaling pathway, inhibited translocation of p65, and decreased the production of cytokines, chemokines, and downstream hydrolysates of cPLA2, arachidonic acid, and leukotriene B4. CONCLUSION: FFD inhibits the cPLA2/ERK/p65 signaling pathway by targeting cPLA2. Therefore, FFD is promising as a therapeutic against cPLA2-involved diseases, particularly ALI.

Clinical value of YKL-40 in patients with polymyositis/dermatomyositis: A cross-sectional study and a systematic review.

INTRODUCTION: We performed a cross-sectional study to investigate the clinical usefulness of YKL-40 in patients with dermatomyositis (DM) and conducted a systematic review to summarize the clinical value of YKL-40 in patients with polymyositis (PM)/DM. MATERIALS AND METHODS: A cross-sectional study and a systematic review were performed to study the clinical value of YKL-40 in patients with PM/DM. Serum YKL-40 level was detected using enzyme-linked immunosorbent assay, and its association with clinical and laboratory parameters was analyzed. In the systematic review, electronic databases of OVID Embase, OVID Medline, and web of science were searched to collect studies that reported clinical use of YKL-40 in patients with PM/DM. RESULTS: In the cross-sectional study, serum YKL-40 level was higher in patients with DM than in healthy controls (median [interquartile range]: 84.09 [52.72-176.4] ng/ml versus 27.37 [12.30-53.58] ng/ml, p < 0.0001). Serum levels of YKL-40 were associated with the course of DM (r = -0.469, p < 0.001), CRP (r = 0.303, p = 0.043), CK (r = 0.263, p = 0.037), and global disease activity (r = 0.628, p < 0.001). The area under the ROC curve was 0.835 (95% confidence interval 0.751-0.920). In the systematic review, a total of four studies were included with moderate to high quality. Serum level of YKL-40 has the possibility for diagnosing PM/DM, identifying PM/DM patients with interstitial lung disease (ILD) or rapid progress ILD, and predicting death. CONCLUSION: Serum YKL-40 level is a possible useful biomarker for PM/DM diagnosis and may be used to predict prognosis.

Effects of medications on incidence and risk of knee and hip joint replacement in patients with osteoarthritis: a systematic review and meta-analysis.

BACKGROUND: This systematic review and meta-analysis aimed to investigate the incidence and risk of knee and hip replacement in patients with osteoarthritis (OA) treated with different medications. METHODS: OVID MEDLINE, OVID EMBASE, Cochrane and Web of Science electronic databases were searched from inception to May 4th, 2022. Clinical trials, including randomized controlled trials, cohort studies and case-control studies, were selected. The meta-analysis effect size was estimated using either incidence with 95% confidence intervals (CIs) or odds ratio (OR)/relative risk (RR) with 95% CIs. The risk of bias and heterogeneity among studies were assessed and analyzed. RESULTS: Forty studies were included, involving 6,041,254 participants. The incidence of joint replacement in patients with OA varied according to the study design and treatments. The incidence of knee arthroplasty varied from 0 to 70.88%, while the incidence of hip arthroplasty varied from 11.71 to 96.43%. Compared to non-users, bisphosphonate users had a reduced risk of knee replacement (RR = 0.71, 95% CI: 0.66-0.77; adjusted hazard ratio [aHR] = 0.76, 95% CI: 0.70-0.83). Compared to intra-articular corticosteroid users, hyaluronic acid (HA) users had a higher risk of knee arthroplasty (RR = 1.76, 95% CI: 1.38-2.25). No publication bias was observed. CONCLUSIONS: Bisphosphonate treatment is associated with a reduced risk of knee replacement. More studies are needed to validate our results due to the limited number of eligible studies and high heterogeneity among studies.

Neoplasm Risk in Patients With Rheumatoid Arthritis Treated With Fostamatinib: A Systematic Review and Meta-analysis.

Objective: This study aimed to assess neoplasm risk in patients with rheumatoid arthritis (RA) treated with fostamatinib. Methods: Studies were collected from electronic databases of OVID Medline, OVID EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science. We included studies that reported neoplasms in patients with RA treated with fostamatinib. Study selection was repeated by two reviewers based on the study selection criteria. Data were collected and methodological quality assessment was performed. Data were pooled using the Peto odds ratio (OR) with a 95% confidence interval (CI). Subgroup analyses of the fostamatinib dose, trial duration, neoplasm nature, and neoplasm-originating systems were conducted. A funnel plot was used to estimate publication bias, and sensitivity analysis was performed to test the robustness of the results. Results: Seven trials involving 4,971 participants showing low to moderate risk of bias were included. Compared with the placebo, fostamatinib use was not associated with the risks of overall neoplasms (Peto OR = 2.62, 95%CI 0.97-7.10), malignant neoplasms (Peto OR = 3.08, 95%CI 0.96-9.91), or benign neoplasms (Peto OR = 1.71, 95%CI 0.26-11.36). Nevertheless, compared with the placebo, a longer duration of fostamatinib use had a higher risk of malignant neoplasms (Peto OR = 4.49, 95%CI 1.03-19.60) at 52 weeks. As for malignant neoplasms in the digestive system, lower doses of fostamatinib reduced the neoplasm risk (100 mg bid vs 150 mg qd: Peto OR = 0.06, 95%CI 0.01-0.59). Sensitivity analysis showed no significant differences in the effective trends, and no publication bias was found. Conclusion: Fostamatinib is not associated with the risks of overall neoplasms as compared to placebo. Nevertheless, a longer duration of fostamatinib use may be associated with a risk of malignant neoplasms and higher doses of fostamatinib may increase malignant neoplasms in the digestive system. Further well-planned cohort studies with a larger study population are needed to elucidate these outcomes. Systematic Review Registration: PROSPERO (CRD42020202121).

Elevated Serum IGFBP-2 and CTGF Levels Are Associated with Disease Activity in Patients with Dermatomyositis.

Background: Insulin-like growth factor-binding proteins (IGFBPs) and connective tissue growth factor (CTGF) participate in angiogenesis. Dermatomyositis (DM) is characterized by microvasculopathy-derived skin lesions. Here, we investigated the clinical significance of serum IGFBP and CTGF levels in DM patients. Methods: In this study, 65 DM patients and 30 healthy controls were enrolled. Serum IGFBP and CTGF levels were examined by ELISA, and their correlation with clinical and laboratory findings was analyzed by Spearman's correlation. Results: Serum IGFBP-2, IGFBP-4, and CTGF levels were higher in DM patients than in healthy controls (median (quartile): 258.9 (176.4-326.1) ng/mL vs. 167.7 (116.1-209.4) ng/mL, p < 0.0001; 450.4 (327.3-631.8) ng/mL vs. 392.2 (339.0-480.2) ng/mL, p = 0.04; and 45.71 (38.54-57.45) ng/mL vs. 35.52 (30.23-41.52) ng/mL, p = 0.001, respectively). IGFBP-2 and CTGF levels were positively correlated with cutaneous (r = 0.257, p = 0.040 and r = 0.427, p = 0.015, respectively) and global (r = 0.380, p = 0.002 and r = 0.292, p = 0.019, respectively) disease activity in DM patients. Conclusion: Serum IGFBP-2 and CTGF levels were increased in patients with DM and correlated with cutaneous and global disease activity.

Effects of medications on incidence and risk of knee and hip joint replacement in patients with osteoarthritis: a systematic review and meta-analysis

Abstract Background: This systematic review and meta-analysis aimed to investigate the incidence and risk of knee and hip replacement in patients with osteoarthritis (OA) treated with different medications. Methods: OVID MEDLINE, OVID EMBASE, Cochrane and Web of Science electronic databases were searched from inception to May 4th, 2022. Clinical trials, including randomized controlled trials, cohort studies and case-control studies, were selected. The meta-analysis effect size was estimated using either incidence with 95% confidence intervals (CIs) or odds ratio (OR)/relative risk (RR) with 95% CIs. The risk of bias and heterogeneity among studies were assessed and analyzed. Results: Forty studies were included, involving 6,041,254 participants. The incidence of joint replacement in patients with OA varied according to the study design and treatments. The incidence of knee arthroplasty varied from 0 to 70.88%, while the incidence of hip arthroplasty varied from 11.71 to 96.43%. Compared to non-users, bisphosphonate users had a reduced risk of knee replacement (RR = 0.71, 95% CI: 0.66-0.77; adjusted hazard ratio [aHR] = 0.76, 95% CI: 0.70-0.83). Compared to intra-articular corticosteroid users, hyaluronic acid (HA) users had a higher risk of knee arthroplasty (RR = 1.76, 95% CI: 1.38-2.25). No publication bias was observed. Conclusion: Bisphosphonate treatment is associated with a reduced risk of knee replacement. More studies are needed to validate our results due to the limited number of eligible studies and high heterogeneity among studies.

Belimumab for Immune-Mediated Necrotizing Myopathy Associated With Anti-SRP Antibodies: A Case Report and Retrospective Review of Patients Treated With Anti-B-Cell Therapy in a Single Center and Literature.

Background: Immune-mediated necrotizing myopathy (IMNM) is characterized by markedly elevated creatinine kinase and histologically scattered necrotic muscle fibers and generally associated with autoantibodies against signal recognition particle (SRP) or 3-hydroxy-3-methylglutaryl-coA-reductase (HMGCR). Poor clinical response to conventional therapies and relapses commonly occur in severe cases. Anti-B-cell therapies have been used in refractory/relapsing cases. Methods: The characteristics of a patient with IMNM associated with anti-SRP antibodies including physical examination, laboratory tests, and disease activity assessment were evaluated. Conventional therapy, belimumab treatment schedule, and follow-up data were recorded. Medical records of IMNM patients treated in our department from September 2014 to June 2021 were reviewed to evaluate the efficacy and safety of anti-B-cell therapy for anti-SRP IMNM. A literature review of patients with anti-SRP IMNM treated with anti-B-cell therapies was performed. Results: We describe a case of a 47-year-old woman with IMNM associated with anti-SRP antibodies who relapsed twice after conventional therapy but showed good response and tolerance to belimumab at 28 weeks follow-up. In this review, three patients from our department were treated with rituximab. Two of the three patients rapidly improved after treatment. Twenty patients and five retrospective studies were included in the literature review. All patients were administered rituximab as an anti-B-cell drug. Conclusion: Despite a lack of rigorous clinical trials, considerable experience demonstrated that anti-B-cell therapy might be effective for patients with IMNM associated with anti-SRP antibodies. Belimumab in association with steroids might be an encouraging option for refractory/relapsing cases.