Objective: Our previous studies revealed that normal synovial exosomes promoted chondrogenesis, and microRNA (miR)-19b-3p independently related to osteoarthritis (OA) risk. Subsequently, this study intended to further explore the effect of OA fibroblast-like synoviocyte (OA-FLS) exosomal miR-19b-3p on OA ferroptosis and its potential mechanisms.Methods: Interleukin (IL)-1β-stimulated chondrocytes and medial meniscus surgery were used to construct the OA cellular model and the OA rat model, respectively. OA-FLS exosomes with/without miR-19b-3p modification were added to the IL-1β-stimulated chondrocytes and OA rat models, followed by direct miR-19b-3p mimic/inhibitor transfection with/without SLC7A11 overexpression plasmids. miR-19b-3p, ferroptosis-related markers (malondialdehyde (MDA), glutathione (GSH)/oxidized glutathione (GSSG), ferrous ion (Fe²⁺), glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), and acyl-CoA synthetase long-chain family member 4 (ACSL4)), mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) levels were detected.Results: Enhanced ferroptosis reflected by dysregulated ferroptosis-related markers, a reduced MMP, and an increased ROS was observed in cartilage tissues from OA patients vs. controls, IL-1β-stimulated chondrocytes vs. normal ones, and OA rat models vs. sham, so did miR-19b-3p. OA-FLS exosomes promoted MDA, Fe²⁺, ACSL4, and ROS but reduced cell viability, GSH/GSSG, GPX4, SLC7A11, and MMP in IL-1β-stimulated chondrocytes, whose effect was enhanced by miR-19b-3p mimics and attenuated by miR-19b-3p inhibitors. miR-19b-3p negatively regulated SLC7A11 and directly bound to SLC7A11 via luciferase reporter gene assay. Furthermore, SLC7A11 overexpression weakened miR-19b-3p mimics’ effect on ferroptosis-related markers, MMP, or ROS in IL-1β-stimulated chondrocytes. OA-FLS exosomes also induced cartilage damage and ferroptosis in OA rats whose influence was tempered by miR-19b-3p inhibitors.Conclusion: OA-FLS exosomal miR-19b-3p enhances cartilage ferroptosis and damage by sponging SLC7A11 in OA, indicating a potential linkage among synovium, cartilage, and ferroptosis during the OA process.

We assessed the efficacy and safety of duloxetine (60 mg, once daily), compared with placebo, during a 13-week treatment period in Chinese patients with chronic pain due to osteoarthritis (OA). Patients were at least 40 years old (male or female) who met American College of Rheumatology clinical and radiographic criteria for the diagnosis of OA of the knee or hip. The primary efficacy measure in this phase 3, randomized, double-blind, placebo-controlled clinical trial was assessment of pain severity by the Brief Pain Inventory (BPI) 24-h Average Pain rating. The clinical trial was conducted at 17 study centers. Statistical approaches included mixed-effects model repeated measures and analysis of covariance. A Fisher exact test was applied to categorical variables. Of 407 patients randomized (duloxetine: N = 205; placebo: N = 202), 166 (81.0%) patients from the duloxetine group and 176 (87.1%) patients from the placebo group completed the 13-week treatment phase. The majority (76.4%) of patients was female; mean age was 60.5 years. Duloxetine-treated patients reported significant pain reduction, compared with placebo treatment, on the BPI 24-h Average Pain rating (least-squares mean (LS Mean) change from baseline to endpoint [95% confidence interval (CI)], duloxetine: -2.23; placebo: -1.73; difference = -0.50 [-0.80, -0.20]; P = 0.001). The incidence of discontinuations due to adverse events was 9.0% in duloxetine-treated patients and 4.5% in placebo-treated patients (P = 0.109). This study demonstrated the efficacy of duloxetine in Chinese patients with chronic pain due to OA. The safety profile of duloxetine observed in this study was consistent with that in previous duloxetine trials. This trial is registered with ClinicalTrials.gov (NCT01931475).

Interleukin- (IL-) 37 is a novel anti-inflammatory cytokine that suppresses immune response and inflammation. This study was performed to determine whether IL-37 was elevated in patients with rheumatoid arthritis (RA) and investigate the correlation between IL-37 level and disease activity and the concentration of Th1/Th2/Th17-related cytokines. Clinical parameters of disease activity, including the 28-joint disease activity score (DAS28) and C-reactive protein (CRP), were collected in 34 RA patients and 34 age- and sex-matched healthy controls. Plasma IL-37 was measured by ELISA. Plasma levels of TNF-α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, G-CSF, GM-CSF, IFN-γ, MCP-1, and MIP-1βwere analyzed using the Bio-Plex suspension array system. It was found that IL-37 levels were elevated markedly in RA patients and almost undetectable in healthy controls. In addition, IL-37 levels in patients with active RA were significantly enhanced as compared with those in patients of remission. More importantly, IL-37 showed a significant correlation with disease activity (DAS28) and IL-4, IL-7, IL-10, IL-12, and IL-13 concentrations in RA patients. These findings suggest that IL-37 plays an important role in the pathogenesis of RA and may prove to be a potential biomarker of active RA.