Ferroportin inhibits the proliferation and migration of fibroblast-like synoviocytes in rheumatoid arthritis via regulating ROS/PI3K/AKT signaling pathway.

The aberrant proliferation of fibroblast-like synoviocytes (FLS) significantly contributes to excessive synovial hyperplasia and joint deformity in rheumatoid arthritis (RA). It has been observed that the membrane iron transporter protein, ferroportin (FPN), is commonly downregulated in tumor cells, while its overexpression can inhibit tumor cell proliferation. However, limited studies have investigated the role of iron in the pathogenesis of RA. In this study, we examined the functional relevance of FPN in RA. The expression of FPN in RA tissue specimens and primary cells was assessed using western blotting and RT-PCR. An adjuvant-induced arthritis (AIA) rat model was established to further validate the expression level of FPN. Phenotypic analysis of FLS cell proliferation was performed via CCK-8, clonogenic formation, and cell scratch assays. The involvement of membrane iron transporter proteins was analyzed through RNAseq and reactive oxygen species (ROS) detection. The results demonstrated decreased expression of FPN in the synovial tissue of RA patients compared to the normal group. Overexpression of FPN can inhibit RA-FLS proliferation and migration by suppressing the PI3K/AKT pathway, and this effect is associated with the elevation of ROS levels. Our findings suggest that the downregulation of FPN may contribute to the pathogenesis of RA, indicating a potential role of iron dysregulation in this disease, and FPN regulates the proliferation and migration of FLS by promoting the levels of ROS in FLS as well as suppressing the PI3K/AKT signaling pathway. These results suggest that FPN could be a potential target for alleviating joint damage in RA.

Shao W ，Liu F ，Zhu L ，Qian W ，Meng Q ，Zhang A ，Jin S ，Lu J ，Yan SG ... -  《-》

Ammopiptanthus nanus (M. Pop.) Cheng f. stem ethanolic extract ameliorates rheumatoid arthritis by inhibiting PI3K/AKT/NF-κB pathway-mediated macrophage infiltration.

Ammopiptanthus nanus (M. Pop.) Cheng f. (A. nanus), a traditional Kirgiz medicinal plant, its stem has shown potential in treating rheumatoid arthritis (RA) in China, either through oral medication or by topical application directly to the affected joints, but its underlying mechanism of action remains unexplored. The purpose of this study is to elucidate pharmacological mechanism of A. nanus in ameliorating RA using a comprehensive approach that combines network pharmacology, molecular docking and experimental evaluations. Firstly, the major constituents of A. nanus stem ethanolic extract were identified and quantified by High-Performance Liquid Chromatography (HPLC). Disease target data from Gene Cards database was then used to define RA-associated targets. A protein-protein interaction (PPI) network was created via STRING database. The DAVID database powered gene ontology (GO) function and kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis to gain functional insights. In vitro, RAW264.7 cells were treated with A. nanus to investigate the roles of target proteins and pathways during lipopolysaccharide (LPS) - induced inflammation. Immunofluorescence assays were performed to assess the effects of A. nanus on macrophage infiltration. The key targets and signalling pathways were validated using enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (RT-qPCR), molecular docking, immunohistochemical analysis, western blotting and immunofluorescence. Finally, the therapeutic potential of A. nanus in RA was evaluated in a carrageenan-induced rat model. Network analysis identified 31 potential targets of A. nanus associated with RA, including 10 hub targets. KEGG analysis highlighted the involvement of PI3K/AKT signaling pathway. In vivo experiments demonstrated that A. nanus treatment significantly protected against carrageenan-induced inflammatory paw tissue and attenuated macrophage infiltration. Both in vivo and in vitro experiments confirmed that A. nanus significantly downregulated the protein expression of COX-2, iNOS and IL-1β, and inhibited PI3K/AKT/NFκB pathway, which are closely linked to RA. Furthermore, molecular docking and cellular thermal shift assay revealed that licoflavanone showed a strong binding affinity with key targets. In summary, this study provides the first evidence of the potent anti-inflammatory activity of A. nanus in experimental RA. The mechanism of action appears to involve inactivation of the PI3K/AKT/NF-κB pathway-mediated macrophage infiltration. These findings indicate that A. nanus has significant potential as a therapeutic potential agent for RA treatment and offer novel insights for future research and drug development in this field.

Yao Y ，Wang J ，Zhang H ，Peng T ，Sun Y ，Zhang R ，Meng X ，Lu X ，Gao Y ，Jin Y ，Zhang Y ，Chen L ... -  《-》

Effect of Aconitum diphtheria on the Proliferation, Apoptosis, and Inflammatory Response of Rheumatoid Arthritis Fibroblast-Like Synoviocytes.

Rheumatoid arthritis (RA), a highly disabling autoimmune disease, is characterized by joint damage and synovial hyperplasia. This paper was designed to explore the effect and mechanisms of Aconitum diphtheria on the proliferation and apoptosis of RA fibroblast-like synoviocytes (RA-FLS). First, RA-FLS was treated with different doses of A. diphtheria extracts. Then, an inverted biological microscope was adopted to observe the RA-FLS morphology. Subsequently, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining, Cell Counting Kit-8 and western blot were utilized to analyze the apoptosis, proliferation, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway-related proteins in RA-FLS, respectively. The experimental results disclosed that, after treatment of RA-FLS with A. diphtheria extracts, the cells became round and the intercellular space was increased. Besides, the RA-FLS proliferation was effectively inhibited by A. diphtheria extracts, while the apoptosis was promoted. Additionally, A. diphtheria extracts could effectively downregulate the expression levels of p-NF-κB (p50), NF-κB (p50), p-NF-κB (p65), and NF-κB (p65). Collectively, A. diphtheria can effectively inhibit RA-FLS proliferation and promote apoptosis in a dose-dependent manner. Similarly, A. diphtheria is able to downregulate p-NF-κB and NF-κB protein expression, but there is no dose-response relationship.

Meng Y ，Cai XL ，Cong S ，Sun J ，Hu YW ，Luo L ... -  《-》

SCORE2 is superior to SCORE in predicting the presence of carotid plaques and intima-media thickness in rheumatoid arthritis patients: a cross-sectional study using carotid ultrasound.

Rheumatoid arthritis (RA) increases the risk of premature mortality, primarily due to cardiovascular diseases (CVD). While Systematic Coronary Risk Evaluation (SCORE) and its updated version SCORE2 are used to estimate CVD risk, these tools may not adequately capture the full cardiovascular risk profile in RA patients. This study aims to compare the effectiveness of SCORE2 versus SCORE in predicting the presence of carotid plaques or increased intima-media thickness (IMT), as detected by ultrasound, in RA patients. This was a single-center cross-sectional study and included adult RA patients with moderate to severe disease who initiated treatment with Janus kinase inhibitors or anti-tumor necrosis factor inhibitors between September 2022 and April 2023. Both SCORE and SCORE2 were calculated for each patient. Carotid ultrasound examinations documented the presence of plaques, and IMT was measured. A total of 122 patients were included. The mean SCORE was 2.48%, while SCORE2 was significantly higher at 4.07% (p < 0.01). SCORE identified 12 (10%) patients as high risk, while SCORE2 identified 99 (81%). Atherosclerotic plaques were present in 34% (n = 42) of participants. Traditional cardiovascular risk factors (dyslipidemia, diabetes, hypertension, and smoking) were significantly associated with ultrasound-detected risk. In 87 cases where SCORE was underestimated, 34 patients (39%) classified as low-moderate risk by SCORE were correctly reclassified as high risk by SCORE2. However, 54 cases classified as high risk by SCORE2 had normal carotid ultrasounds. The sensitivity of SCORE for predicting plaque presence was 21%, compared to 100% for SCORE2. Combining SCORE with carotid ultrasound increased the detection of high-risk patients from 10% to 38%. However, adding carotid ultrasound to SCORE2 did not increase the detection rate beyond 81%. Our findings highlight the superior performance of SCORE2 compared to SCORE in identifying RA patients with carotid ultrasound abnormalities, thus indicating a higher cardiovascular risk.

Campos Fernández C ，Fragío Gil JJ ，González Mazarío R ，Martínez Calabuig P ，Román Ivorra JA ... -  《-》

BACH1 as a key driver in rheumatoid arthritis fibroblast-like synoviocytes identified through gene network analysis.

RNA-sequencing and differential gene expression studies have significantly advanced our understanding of pathogenic pathways underlying rheumatoid arthritis (RA). Yet, little is known about cell-specific regulatory networks and their contributions to disease. In this study, we focused on fibroblast-like synoviocytes (FLS), a cell type central to disease pathogenesis and joint damage in RA. We used a strategy that computed sample-specific gene regulatory networks to compare network properties between RA and osteoarthritis FLS. We identified 28 transcription factors (TFs) as key regulators central to the signatures of RA FLS. Six of these TFs are new and have not been previously implicated in RA through ex vivo or in vivo studies, and included BACH1, HLX, and TGIF1. Several of these TFs were found to be co-regulated, and BACH1 emerged as the most significant TF and regulator. The main BACH1 targets included those implicated in fatty acid metabolism and ferroptosis. The discovery of BACH1 was validated in experiments with RA FLS. Knockdown of BACH1 in RA FLS significantly affected the gene expression signatures, reduced cell adhesion and mobility, interfered with the formation of thick actin fibers, and prevented the polarized formation of lamellipodia, all required for the RA destructive behavior of FLS. This study establishes BACH1 as a central regulator of RA FLS phenotypes and suggests its potential as a therapeutic target to selectively modulate RA FLS.

Pelissier A ，Laragione T ，Harris C ，Rodríguez Martínez M ，Gulko PS ... -  《Life Science Alliance》