Anti-malarial drug artesunate can suppress inflammation and prevent cartilage and bone destruction in collagen-induced arthritis model in rats—suggesting it may be a potent drug for rheumatoid arthritis (RA) therapy. We aimed to investigate its effect on the invasive property of fibroblast-like synoviocytes (FLS) from patients with RA. Synovial tissues were obtained by closed needle biopsy from active RA patients, and FLS were isolated and cultured in vitro. RA-FLS were treated with artesunate at various concentrations, while methotrexate or hydroxychloroquine was employed as comparator drugs. Cell viability, proliferation, cell cycle, apoptosis, migration, invasion, and pseudopodium formation of RA-FLS were assessed by CCK-8 assays, EdU staining, Annexin V-FITC/PI staining, transwell assays, or F-actin staining, respectively. Further, relative changes of expressed proteases were analyzed by Proteome profiler human protease array and verified by quantitative real-time PCR (qPCR), Western blot, and ELISA. The expression of signaling molecules of MAPK, NF-κB, AP-1, and PI3K/Akt pathways were measured by qPCR and Western blot. PDK-1 knockdown by specific inhibitor AR-12 or siRNA transfection was used to verify the pharmacological mechanism of artesunate on RA-FLS. Artesunate significantly inhibited the migration and invasion of RA-FLS in a dose-dependent manner with or without TNF-α stimulation. The effect was mediated through artesunate inhibition of MMP-2 and MMP-9 production, and pre-treatment with exogenous MMP-9 reversed the inhibitory effect of artesunate on RA-FLS invasion. Artesunate had a stronger inhibitory effect on migration and invasion of RA-FLS as well as greater anti-inflammatory effect than those of hydroxychloroquine. Similar inhibitory effect was detected between artesunate and methotrexate, and synergy was observed when combined. Mechanistically, artesunate significantly inhibited PDK-1 expression as well as Akt and RSK2 phosphorylation—in a similar manner to PDK-1-specific inhibitor AR-12 or PDK-1 knockdown by siRNA transfection. This inhibition results in suppression of RA-FLS migration and invasion as well as decreased MMP-2 and MMP-9 expression. Our study demonstrates artesunate is capable of inhibiting migration and invasion of RA-FLS through suppression of PDK1-induced activation of Akt and RSK2 phosphorylation—suggesting that artesunate may be a potential disease-modifying anti-rheumatic drug for RA.

Previous studies have revealed that hepatitis B virus (HBV) infection may be associated with rheumatoid arthritis (RA), while there are no further clinical studies regarding the role of HBV infection in RA progression during disease-modifying anti-rheumatic drug (DMARD) therapy. Here, we aimed to explore the influence of HBV infection on radiographic and clinical outcomes among patients with RA in a clinical practice setting. Thirty-two consecutive patients with RA (Disease Activity Score 28-joint assessment based on C-reactive protein (DAS28-CRP) ≥2.6) with chronic HBV infection (CHB) were retrospectively recruited as the CHB group and 128 age-matched, sex-matched, and disease activity-matched contemporary patients with RA without CHB were included in the non-CHB group. Clinical data were collected at baseline and visits at month 1, 3, 6, and 12. The therapeutic target was defined as DAS28-CRP <2.6 in all patients or 24 months). The primary outcome was the percentage of patients with one-year radiographic progression (a change in modified total Sharp score ≥0.5). Compared with the non-CHB group, a significantly higher percentage of patients with one-year radiographic progression was observed in the CHB group (53% vs. 17%, p < 0.001), with smaller proportions of patients achieving therapeutic target at month 6 and month 12 (53% vs. 82% and 53% vs. 75%, both p < 0.05), remission at month 6 (DAS28-CRP <2.6, 50% vs. 72%, p = 0.039), and American College of Rheumatology (ACR)20/50 responses and good or moderate European League Against Rheumatism (EULAR) responses mainly at month 6 and 12 (all p < 0.05). Multivariate logistic regression analysis revealed that CHB status was significantly associated with one-year radiographic progression and failure to achieve therapeutic target within 6 months. HBV reactivation occurred in 34% of patients with CHB during one-year follow up, with two patients suffering hepatitis flare. HBV infection may play a deleterious role in radiographic and clinical outcomes in patients with RA, and HBV reactivation should be paid close attention during immunosuppressive therapy.