Search

Rheumatoid arthritis (RA) remains a formidable healthcare challenge due to its chronic nature and potential for irreversible joint damage. Methotrexate (MTX) is a cornerstone treatment for RA but carries significant risks of adverse effects with repeated administration, necessitating the exploration of alternative delivery methods. Injectable hydrogels loaded with MTX for intra-articular injection present a promising solution, allowing sustained drug release directly into affected joints. However, current hydrogel systems often lack extended therapeutic periods and the ability to self-regulate drug release according to disease state. Furthermore, RA is associated with excessive production of reactive oxygen species (ROS), which exacerbates inflammation and joint damage. Herein, we developed an advanced injectable hydrogel (MPDANPs/MTX HA-PEG gel) based on "bio-orthogonal chemistry", combining hyaluronic acid and polyethylene glycol (PEG) matrices co -loaded with mesoporous polydopamine nanoparticles (MPDANPs) and MTX. MPDANPs/MTX HA-PEG gel achieved prolonged, staged, and self-regulated MTX release, coupled with ROS scavenging capabilities for enhanced therapeutic efficacy. Due to its optimized MTX release behavior and significant ROS scavenging function, MPDANPs/MTX HA-PEG gel exhibited potent anti-inflammatory effects in collagen-induced arthritis (CIA) rats following a single intra-articular injection. Our findings highlight the potential of MPDANPs/MTX HA-PEG gel as a highly effective treatment strategy for RA, offering a promising avenue for improving patient outcomes. [Display omitted] • MPDANPs/MTX HA-PEG gel enabled prolonged, staged, and ROS-responsive MTX release. • Optimized MTX release behavior, combined with ROS scavenging capacities, contributed to efficient RA therapy. • Single intra-articular injection of MPDANPs/MTX HA-PEG gel showed significant anti-inflammatory effects in CIA rats. [ABSTRACT FROM AUTHOR]

Background: Rheumatoid arthritis, a chronic autoimmune disease, is characterized by synovial hyperplasia and cartilage erosion. Here, we investigated the potential mechanism of action of quercetin, the main component of flavonoids, in treating rheumatoid arthritis. Object: To examine the anti-arthritic effects of quercetin and elucidate the specific mechanisms that differentiate its metabolic effects on autoimmune and inflammatory responses at the synovial cell level. Methods: We created a collagen-induced arthritis (CIA) model in Wistar rats, which were administered quercetin (50 or 100 mg/kg) continuously for four weeks via stomach perfusion. The arthritis score, histopathological staining, radiological assessment, and serum biochemical parameters were used to study the impact of quercetin on disease improvement. Additionally, immunofluorescence was employed to detect JAK1/STAT3/HIF-1α expression in rat joints. Moreover, the effects of quercetin (20, 40, and 80 µmol/L) on the properties and behavior of synovial fibroblasts were evaluated in an in vitro MH7A cell model using flow cytometry, CCK8, and transwell assays. Further, the mRNA expression levels of inflammatory cytokines IL1β, IL6, IL17, and TNFα were assessed by quantitative real-time PCR. Glucose, lactate, lactate dehydrogenase, pyruvate, pyruvate dehydrogenase, and adenosine triphosphate assay kits were employed to measure the metabolic effects of quercetin on synovial fibroblasts. Finally, immunoblotting was used to examine the impact of quercetin on the JAK1/STAT3/HIF-1α signaling pathway in synovial fibroblasts. Results: In vivo experiments confirmed the favorable effects of quercetin in CIA rats, including an improved arthritis score and reduced ankle bone destruction, in addition to a decrease in the pro-inflammatory cytokines IL-1β, IL-6, IL-17, and TNF-α in serum. Immunofluorescence verified that quercetin may ameliorate joint injury in rats with CIA by inhibiting JAK1/STAT3/HIF-1α signaling. Various in vitro experiments demonstrated that quercetin effectively inhibits IL-6-induced proliferation of MH7A cells and reduces their migratory and invasive behavior, while inducing apoptosis and reducing the expression of the pro-inflammatory cytokines IL1β, IL6, IL17, and TNFα at the mRNA level. Quercetin caused inhibition of glucose, lactate, lactate dehydrogenase, pyruvate, and adenosine triphosphate and increased pyruvate dehydrogenase expression in MH7A cells. It was further confirmed that quercetin may inhibit energy metabolism and inflammatory factor secretion in MH7A cells through JAK1/STAT3/HIF-1α signaling. Conclusions: Quercetin's action on multiple target molecules and pathways makes it a promising treatment for cartilage injury in rheumatoid arthritis. By reducing joint inflammation, improving joint metabolic homeostasis, and decreasing immune system activation energy, quercetin inhibits the JAK1/STAT3/HIF-1α signaling pathway to improve disease status. [ABSTRACT FROM AUTHOR]

Simple Summary: The use of medicinal traditional plants and plant-derived compounds in the treatment of inflammatory states, including rheumatoid arthritis, is gaining attention due to their anti-inflammatory and immunomodulatory properties and fewer side effects compared to conventional drugs. The current study aimed to evaluate the therapeutic effects of the Mediterranean plant Teucrium montanum L. on collagen-induced arthritis in rats, in an in vivo animal model of rheumatoid arthritis. The effect of the Teucrium montanum extract was evaluated by examining the cellular and molecular components of innate and adaptive immunity that have been shown to play an important role in the pathogenesis of both rheumatoid arthritis and collagen-induced arthritis. The Teucrium montanum extract alleviated the clinical manifestation and improved the histopathological findings of arthritis in CIA. The extract improved the anti-/pro-oxidative balance in serum, suppressed the production of pro-inflammatory cytokines in affected joints, and suppressed the T cell responses in secondary lymphoid organs and the production of autoantibodies. Our results suggest the anti-inflammatory/immunomodulatory properties of Teucrium montanum extract and represent a basis for the further exploration of the possible therapeutic use of the extract or its compound/s. The anti-inflammatory/immunomodulatory effects of Teucrium montanum L. (TM), a plant distributed in the Mediterranean region, have been insufficiently examined. The effects of the TM ethanol extract were tested in a rat collagen-induced arthritis (CIA) model of rheumatoid arthritis. LC-MS was used for the phytochemical analysis of the TM extract. Dark Agouti rats were immunized with bovine type II collagen (CII) in incomplete Freund's adjuvant for CIA, and treated with 100 or 200 mg/kg of TM extract daily via oral administration. Clinical and histopathological evaluations and a flow cytometric analysis of the phenotypic and functional characteristics of splenocytes and draining lymph node cells were performed. The cytokines in the paw tissue culture supernatants and anti-CII antibodies in serum were determined by ELISA. The TM extract, with the dominant components verbascoside and luteolin 7-O-rutinoside, reduced the arthritic score and ankle joint inflammation in CIA rats, promoted the antioxidant profile in serum, and lowered pro-inflammatory TNF-α, IL-6 and IL-1β production. It suppressed the activation status of CD11b+ cells by lowering CD86, MHCII and TLR-4 expression, and promoted the Th17/T regulatory cell (Tregs) balance towards Tregs. A lower frequency of B cells was accompanied by a lower level of anti-CII antibodies in treated rats. These findings imply the favorable effect of TM extract on the clinical presentation of CIA, suggesting its anti-inflammatory/immunomodulatory action and potential therapeutic effect. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic condition characterized by inflammation and an abnormal immune response. N6-methyladenosine (m6A) methylation has altered nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing (NLRP) 3. This change is implicated in the regulation of cell pyroptosis and inflammation. WTAP has a crucial role in regulating NLRP3 m6A. In this work, we used a rat model of collagen-induced arthritis (CIA) to investigate the involvement of WTAP in the evolution of inflammation in RA. The purpose of silencing or overexpressing WTAP in RA-fibroblast-like synoviocytes (RA-FLSs) treated with TNF-α was to identify its impact on pyroptosis, NLRP3 inflammasome-related proteins, the secretion of pro-inflammatory cytokines and migration. Bioinformatics techniques were used to pinpoint the exact target controlled by WTAP. To assess WTAP and NLRP3's role in RA-FLSs, we used methylated RNA immunoprecipitation, LDH test, flow cytometry, RT-qPCR, Western blotting, and Transwell. Our results show that WTAP expression is upregulated in both RA rats and cell models. Cell pyroptosis, NLRP3-related pro-inflammatory cytokines, and migration were reduced in TNF-α-treated RA-FLSs when WTAP was knocked down, whereas overexpression of WTAP displayed the opposite effect in RA-FLSs. WTAP mediated m6A modification in the NLRP3 mRNA and enhanced its mRNA stability. These results suggested that WTAP promoted FLSs pyroptosis and related inflammatory response via NLRP3 and identified WTAP as a potential target for treating RA. [ABSTRACT FROM AUTHOR]

[Display omitted] Rheumatoid arthritis (RA) is an inflammatory autoimmune disease triggered by antigenic peptides with environmental and genetic risk factors. It has been shown that antigen-specific targeting could be a promising therapeutical strategy for RA by restoring immune tolerance to self-antigens without compromising normal immunity. Citrullination of antigens enhances antigenic properties and induces autoimmune responses. Here, we showed that citrullinated antigenic (citAg) vaccine ameliorated collagen-induced arthritis with decreased T-helper 1 (Th1) and Th17 cells, downregulated proinflammatory cytokines including interlukin-6 and tumor necrosis factor-α, and inhibited antigen recall responses. B cell receptor sequencing further revealed that citAg vaccine could dampen the dysregulated V(D)J recombination, restoring the immune repertoire. Taken together, the results demonstrated that citAg vaccine might have a therapeutic effect on RA. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a debilitating autoimmune disease characterized by chronic joint inflammation and cartilage damage. Current therapeutic strategies often result in side effects, necessitating the development of targeted and safer treatment options. This study introduces a novel nanotherapeutic system, 2-APB@DGP-MM, which utilizes macrophage membrane (MM)-encapsulated nanoparticles (NPs) for the targeted delivery of 2-Aminoethyl diphenylborinate (2-APB) to inflamed joints more effectively. The NPs are designed with a matrix metalloproteinase (MMP)-cleavable peptide, allowing for MMP-responsive drug release within RA microenvironment. Comprehensive in vitro and in vivo assays confirmed the successful synthesis and loading of 2-APB into the DSPE-GPLGVRGC-PEG (DGP) NPs, as well as their ability to repolarize macrophages from a pro-inflammatory M1 to an anti-inflammatory M2 phenotype. The NPs demonstrated high biocompatibility, low cytotoxicity, and enhanced cellular uptake. In a collagen-induced arthritis (CIA) mouse model, intra-articular injection of 2-APB@DGP-MM significantly reduced synovial inflammation and cartilage destruction. Histological analysis corroborated these findings, demonstrating marked improvements in joint structure and delayed disease progression. Above all, the 2-APB@DGP-MM nanotherapeutic system offers a promising and safe approach for RA treatment by modulating macrophage polarization and delivering effective agents to inflamed joints. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) involves chronic inflammation, oxidative stress, and complex immune cell interactions, leading to joint destruction. Traditional treatments are often limited by off-target effects and systemic toxicity. This study introduces a novel therapeutic approach using hyaluronic acid (HA)-conjugated, redox-responsive polyamino acid nanogels (HA-NG) to deliver tacrolimus (TAC) specifically to inflamed joints. The nanogels' disulfide bonds enable controlled TAC release in response to high intracellular glutathione (GSH) levels in activated macrophages, prevalent in RA-affected tissues. In vitro results demonstrated that HA-NG/TAC significantly reduced TAC toxicity to normal macrophages and showed high biocompatibility. In vivo, HA-NG/TAC accumulated more in inflamed joints compared to non-targeted NG/TAC, enhancing therapeutic efficacy and minimizing side effects. Therapeutic evaluation in collagen-induced arthritis (CIA) mice revealed HA-NG/TAC substantially reduced paw swelling, arthritis scores, synovial inflammation, and bone erosion while suppressing pro-inflammatory cytokine levels. These findings suggest that HA-NG/TAC represents a promising targeted drug delivery system for RA, offering potential for more effective and safer clinical applications. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) involves chronic inflammation, oxidative stress, and complex immune cell interactions, leading to joint destruction. Traditional treatments are often limited by off-target effects and systemic toxicity. This study introduces a novel therapeutic approach using hyaluronic acid (HA)-conjugated, redox-responsive polyamino acid nanogels (HA-NG) to deliver tacrolimus (TAC) specifically to inflamed joints. The nanogels' disulfide bonds enable controlled TAC release in response to high intracellular glutathione (GSH) levels in activated macrophages, prevalent in RA-affected tissues. In vitro results demonstrated that HA-NG/TAC significantly reduced TAC toxicity to normal macrophages and showed high biocompatibility. In vivo, HA-NG/TAC accumulated more in inflamed joints compared to non-targeted NG/TAC, enhancing therapeutic efficacy and minimizing side effects. Therapeutic evaluation in collagen-induced arthritis (CIA) mice revealed HA-NG/TAC substantially reduced paw swelling, arthritis scores, synovial inflammation, and bone erosion while suppressing pro-inflammatory cytokine levels. These findings suggest that HA-NG/TAC represents a promising targeted drug delivery system for RA, offering potential for more effective and safer clinical applications. [ABSTRACT FROM AUTHOR]

Arsenic trioxide (ATO) is now part of the standard regimen for the treatment of newly diagnosed and relapsed acute promyelocytic leukemia. The availability of an oral form of ATO has greatly reduced the incidence of cardiotoxicity as compared to intravenous (IV) administration. Increasing evidence suggests that ATO has anti-inflammatory properties that may be useful for the treatment of autoimmune diseases. These include the modulation of Treg cell activation, Th1/Th2 and Th17/Treg balance, depletion of activated T cells and plasmacytoid dendritic cells, and influence of B-cell differentiation, leading to reduced autoantibody and cytokine production. ATO has also been shown to induce apoptosis of activated fibroblast-like synoviocytes through the generation of reactive oxygen species and alter the gut microbiota in collagen-induced arthritis. Despite the emergence of newer treatment modalities, the treatment of systemic lupus erythematosus (SLE), especially refractory manifestations, remains a challenge, owing to the paucity of effective biological and targeted therapies that are devoid of adverse effects. Oral ATO is an attractive option for the treatment of SLE because of the lower cost of production, convenience of administration, and reduced cardiotoxicity. This article summarizes the anti-inflammatory mechanisms of ATO and its potential application in the treatment of SLE and other rheumatic diseases. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that mainly affects the joints. Studies have shown that memory CD4+ T cells play an important role in the pathogenesis of RA. This study investigated the expression and function of CD305 on human memory CD4+ T cells and the effects of CD305 activating antibody on collagen-induced arthritis. The results showed that CD305 expression was significantly decreased on circulating memory CD4+ T cells from patients with RA and its mean fluorescence intensity (MFI) was negatively correlated with DAS28. Moreover, CD305 inhibited the activation of memory CD4+ T cells by down-regulating CD69 and CD25 and the production of IFN-γ, IL-4, and IL-17A induced by anti-CD3/CD28 antibodies. In addition, activation of CD305 inhibited the severity of disease in collagen-induced arthritis. In summary, CD305 reduction may mediate the excessive activation of memory CD4+ T cells and participate in the development of RA. It can be used as a predictive marker of disease activity and has potential medicinal value in the treatment of RA. • CD305 decreases prominently on circulating memory CD4+ T cells and is negatively correlated with DAS28 of patients with RA. • CD305 participates in the abnormal activation of memory CD4+ T cells in patients with RA. • CD305 inhibits secretion of IFN-γ, IL-4 and IL-17A by memory CD4+ T cells. • CD305 attenuates arthritis severity in Collagen-induced arthritis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Preliminary research by our group suggests that targeting fibroblast growth factor receptor 1 (FGFR1) may be an effective strategy for treating RA. OBJECTIVE: To investigate the effects of an FGFR1 inhibitor (PD173074) on bone destruction in rats with collagen-induced arthritis. METHODS: Twenty-five female Sprague-Dawley rats were randomly divided into five groups: normal control group, model group, methotrexate group, low- dose PD173074 group, and high-dose PD173074 group. Except for the normal control group, rat models of type II collagen-induced arthritis were made in each group. After successful modeling, rats were injected intraperitoneally with sterile PBS in the normal and model groups, 1.04 mg/kg methotrexate in the methotrexate group, and 5 and 20 mg/kg in the low-dose group and high-dose PD173074 groups, once a week. After 4 weeks of drug administration, clinical symptoms and joint swelling in rats were observed. Micro-CT was used for three-dimensional reconstruction and analysis of the ankle joints. Pathological changes in the ankle joints were observed. Periarticular angiogenesis and the expression of receptor activator of nuclear factor-κB ligand were detected. The expression levels of p-FGFR1, vascular endothelial growth factor A, and tartrate-resistant acid phosphatase in the synovial membrane were measured. Pathological changes in the liver, spleen, and kidney were observed and liver, spleen, and kidney indices were calculated. RESULTS AND CONCLUSION: PD173074 could alleviate clinical symptoms and joint swelling, delay bone loss, improve bone structure, reduce synovial invasion and cartilage bone erosion, reduce the number of periarticular osteoclasts, inhibit angiogenesis in synovial tissues, reduce the expression of receptor activator of nuclear factor-κB ligand, and inhibit the expression of FGFR1 phosphorylated protein, tartrate-resistant acid phosphatase and vascular endothelial growth factor A. Pathologic observation of the liver, spleen and kidney in rats showed no obvious toxic side effects after PD173074 treatment. To conclude, the FGFR1 inhibitor can delay the progression of joint inflammation and bone destruction and inhibit angiogenesis in the rat model of type II collagen-induced arthritis. The therapeutic effect of PD173074 has been preliminarily validated in the type II collagen-induced arthritis model and may act by inhibiting FGFR1 phosphorylation, which provides a direction for the search of new therapeutic targets for rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Rheumatoid arthritis is an inflammatory disease. Many studies have shown that wogonin has a good anti-inflammatory effect on rheumatoid arthritis, but its exact efficacy and specific mechanism of action remain to be clarified. OBJECTIVE: To investigate the mechanism of wogonin ameliorating joint inflammation by regulating endoplasmic reticulum stress pathway in rats with collagen- induced arthritis. METHODS: (1) At the animal level: Female Wistar rats were divided into healthy control group, arthritis model group and wogonin treatment group. Rat models of arthritis in the latter two groups were established by subcutaneous injection of bovine type II collagen and adjuvant. In the wogonin group, wogonin was given by gavage for 28 consecutive days after modeling. During this period, the rats in each group were weighed, and arthritis score and ankle swelling were measured every 7 days. After the experiment, the pathological changes of the joint were observed, the mRNA and protein levels of endoplasmic reticulum stress pathway GRP78 and CHOP were detected by qRT-PCR, western blot, and immunohistochemistry. (2) At the cellular level, cell counting kit-8 was used to detect the cytotoxic effect of wogonin on fibroblast-like synoviocytes from rats with collagen-induced arthritis. The fibroblast-like synoviocytes induced by thapsigargin were treated with different concentrations of wogonin. The levels of interleukin-1β and tumor necrosis factor-α in the cell supernatant were detected by ELISA, and the intracellular reactive oxygen species in each group were determined by DCFH-DA probe method. The mRNA and protein levels of GRP78, IRE1α, XBP1s and CHOP were detected by qRT-PCR and western blot, respectively. RESULTS AND CONCLUSION: Compared with the healthy control group, arthritis index score and ankle swelling degree in the arthritis model group were increased (P < 0.01), synovial hyperplasia, inflammatory cell infiltration, cartilage destruction and bone erosion were observed in pathological sections, and the mRNA and protein expressions of GRP78 and CHOP in the ankle were significantly increased (P < 0.01), which were mainly located in synovial tissue and articular surface. Compared with the arthritis model group, the arthritis index score and ankle swelling degree in the wogonin treatment group were decreased (P < 0.05), synovial hyperplasia and the number of inflammatory cells were decreased, cartilage destruction and bone erosion were alleviated, the mRNA and protein expression levels of GRP78 and CHOP in the ankle were decreased (P < 0.05), particularly in synovial tissue and on the articular surface. There was no significant difference in body mass among the three groups (P > 0.05). In the cell experiment, 200 μmol/L wogonin significantly reduced the survival rate of fibroblast-like synoviocytes (P < 0.01). Compared with the blank control group, the levels of interleukin-1β, tumor necrosis factor-α, content of reactive oxygen species, and mRNA and protein expression of GRP78, IRE1α, XBP1s, and CHOP in the thapsigargin group were significantly increased (P < 0.05); compared with the thapsigargin group, 50 and 100 μmol/L wogonin significantly reduced the levels of interleukin-1β and tumor necrosis factor-α in the cell supernatant (P < 0.05, P < 0.01), and 100 μmol/L wogonin significantly reduced the content of reactive oxygen species (P < 0.01) and down-regulated the mRNA and protein expression levels of GRP78, IRE1α, XBP1s and CHOP (all P < 0.05). These results suggest that wogonin can effectively alleviate joint inflammatory responses in rats with collagen-induced arthritis, and the endoplasmic reticulum stress pathway may be the key target of its intervention. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic disease characterized by persistent synovitis and angiogenesis. Its clinical manifestations are synovial hyperplasia and progressive destruction of bone and cartilage, eventually leading to joint deformation and even disability. The healing effect of monomer stigmasterol, the main active ingredient of the Jinwujiangu recipe the Chinese Herbal Compound, on RA has been confirmed in several studies. Fibroblast-like synoviocytes (FLS) are related to the occurrence and development of RA. This study aims to investigate the effects of stigmasterol on FLS cell proliferation and apoptosis, as well as its impact on FLS cell cycle proteins and key genes in the Phosphatidylinositol 3 kinase/protein kinase B (PI3K/AKT) pathway, providing insights into the development of stigmasterol as an alternative therapeutic drug for RA. We administered 20 g/kg stigmasterol to rats continuously for 5 d to obtain stigmasterol-containing serum, and established rat models of osteoarthritis induced by ossein to obtain FLS. To explore the effects of stigmasterol on the viability, migration, proliferation and apoptosis of collagen-induced arthritis (CIA)-FLS cells, we selected 0% (control), 5% (low concentration), 10% (medium concentration) and 20% (high concentration) drug-containing serum to intervene cells and conducted Cell Counting Kit-8 (CCK- 8), Transwell, 5-ethynyl-2’ -deoxyuridine (EdU) staining and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) experiments, respectively. The results showed that compared with the control group, low, medium, and high serum significantly inhibited the activity, migration, and proliferation of FLS cells, and promoted their apoptosis, and high serum had the best effect. In addition, we investigated the mechanism of stigmasterol inhibiting FLS proliferation and promoting its apoptosis by qPCR, Western blot, and immunofluorescence assays. The results showed that stigmasterol significantly inhibited the expression of Cyclin D1, cyclin-dependent kinase 4 (CDK4), and Retinoblastoma (Rb), and decreased the expression of key genes kinase insert domain-containing receptor (KDR), PI3K, AKT, phosphorylated PI3K (p-PI3K) and phosphorylated AKT (p-AKT) in the KDR-mediated PI3K/AKT signaling pathway, thus inhibiting the proliferation of FLS and promoting the apoptosis of FLS. It was suggested that stigmasterol may be a potential alternative drug for RA treatment. [ABSTRACT FROM AUTHOR]

Qianjinba is primarily cultivated in the southern regions of China and finds extensive use in traditional Chinese medicine (TCM) for conditions such as rheumatism, arthralgia, and gynecological ailments. It has been officially recognized as a protected variety of TCM by the state. The aim of this study was to investigate the therapeutic potential of Qianjinba polysaccharide (QJBDT) in treating rheumatoid arthritis (RA) in mice, along with a preliminary exploration of its mechanisms for inhibiting RA in these animals. Kunming mice (KM) were randomly divided into several groups, including a normal group, a model group (LPS group), low-dose, medium-dose, and high-dose QJBDT groups, as well as a positive control group (TGP group), each consisting of 10 mice. To induce inflammation and create an RA model, type II collagen was injected into the right hind foot joint. Following a 7-day modeling period, various concentrations of QJBDT and the positive control drug total glycoside of peony were administered via gavage once a day for 21 consecutive days. Throughout the study, we monitored and recorded the mice's weight, measured foot swelling, and assessed the arthritis index on a weekly basis. We also conducted pathological examinations of joint tissues and analyzed the signal pathway of p38 mitogen-activated protein kinase (MAPK) as well as the protein expression of nuclear factor NF-κB in the mice's right foot joint tissues. Additionally, we employed ELISA to detect the levels of interleukin-β (IL-β), IL-17, and tumor necrosis factor-α (TNF-α) in the mice's serum. The results of this study revealed that QJBDT effectively reduced the degree of foot swelling and the arthritis index in collagen-induced arthritis mice while improving their weight loss (P < 0.05). Furthermore, it alleviated the pathological damage observed in the mice's joints. Notably, the expression of transcription factors p38 and NF-κB proteins was down-regulated (P < 0.05), and the levels of inflammatory cytokines IL-β, IL-17, and TNF-α in the mice's serum were decreased (P < 0.05). In conclusion, this study demonstrated that polysaccharides could inhibit the expression of transcription factors p38 and NF-κB, reduce the production of inflammatory factors, and alleviate the progression of RA to a certain extent. [ABSTRACT FROM AUTHOR]

Summary: Rheumatoid arthritis (RA) is considered a multifactorial condition where interaction between the genetic and environmental factors lead to immune dysregulation causing autoreactivity. While among the various genetic factors, HLA‐DR4 and DQ8, have been reported to be the strongest risk factors, the role of various environmental factors has been unclear. Though events initiating autoreactivity remain unknown, a mucosal origin of RA has gained attention based on the recent observations with the gut dysbiosis in patients. However, causality of gut dysbiosis has been difficult to prove in humans. Mouse models, especially mice expressing RA‐susceptible and ‐resistant HLA class II genes have helped unravel the complex interactions between genetic factors and gut microbiome. This review describes the interactions between HLA genes and gut dysbiosis in sex‐biased preclinical autoreactivity and discusses the potential use of endogenous commensals as indicators of treatment efficacy as well as therapeutic tool to suppress pro‐inflammatory response in rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation and swelling. Several studies have demonstrated that RA fibroblast-like synovial cells (RA-FLS) play an important role in RA pathogenesis. Activated RA-FLS contribute to synovial inflammation by secreting inflammatory cytokines including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α. LMT-28 is derivative of oxazolidone and exerts anti-inflammatory effects on RA via IL-6 signaling pathway regulation. LMT-28 also regulates T cell differentiation in RA condition. However, the effect of LMT-28 on the migration and invasion of RA-FLS remains unknown. Kaempferol has been reported to have pharmacological effects on various diseases, such as inflammatory diseases, autoimmune diseases, and cancer. Additionally, kaempferol has been reported to inhibit RA-FLS migration and invasion, but it is not known about the therapeutic mechanism including molecular mechanism such as receptor. The present study aimed to investigate the synergistic effects of the combined treatment of LMT-28 and kaempferol on RA-FLS activation and RA pathogenesis in mouse model. LMT-28 and kaempferol co-administration inhibited RA disease severity and histological collapse in the joint tissues of CIA mice, as well as downregulated the levels of pro-inflammatory cytokines in mouse serum. Additionally, the combined treatment inhibited excessive differentiation of T helper 17 cells and osteoclasts. Furthermore, compared with single treatments, combined treatment showed enhanced inhibitory effects on the hyperactivation of IL-6-induced signaling pathway in RA-FLS. Combined treatment also inhibited RA-FLS cell proliferation, migration, and invasion and suppressed the expression of matrix metalloproteinase in RA-FLS. Furthermore, we confirmed that the combined treatment inhibited chondrocyte proliferation, migration, and invasion. In conclusion, our results suggest that the combined treatment of LMT-28 and kaempferol exerts a synergistic effect on the RA development via the regulation of IL-6-induced hyperactivation of RA-FLS. Furthermore, this study suggests that combination therapies can be an effective therapeutic option for arthritis. [ABSTRACT FROM AUTHOR]

Rheumatoid Arthritis (RA) is a chronic autoimmune condition causing joint inflammation and damage. Despite treatment progress, effective topical therapies pose challenges. Animal models, like Collagen-Induced Arthritis (CIA) and Adjuvant-Induced Arthritis (AIA), mimic RA pathogenesis, aiding preclinical evaluation of topical treatments. By studying these models, experts can assess the efficacy, safety and pharmacokinetics of novel topical treatments, thereby accelerating their translation into clinical practice. Optimizing drug delivery, bioavailability and minimizing side effects are critical in formulation development. Animal studies refine parameters such as vehicle selection, drug concentration and application frequency for maximal therapeutic benefit. These models also deepen understanding of RA mechanisms, informing targeted topical therapy design against specific inflammatory mediators or immune cells. Lastly, animal models accelerate topical RA treatment development, providing vital data and mechanistic insights. Leveraging these models enhances formulation safety and efficacy, potentially improving patient outcomes. [ABSTRACT FROM AUTHOR]

Simple Summary: Auto-immune disorders, such as rheumatoid arthritis, are characterized by high levels of pro-inflammatory cytokines. Continued exposure to high levels of systemic inflammation has several other health consequences, including negative effects on organs such as the brain. These detrimental effects may result in mood and neurological disorders. However, the exact mechanisms through which inflammation can result in mood disturbances and neurological disorders are not well known and are difficult to study in humans. The collagen-induced arthritis (CIA) rat model has been used to mimic human autoimmune disorders and systemic inflammation. In this study, we used the CIA model to gain a better understanding of the role of inflammation on the processes that may be involved in mood and neurological disorders, by looking at several molecular markers in different brain regions. Our results showed that all the brain regions studied in the CIA rats had high levels of local inflammation, which may have resulted in cell death in these areas. We also showed that the markers associated with neuron health and neurotransmitters implicated in mood disturbances were dysregulated in some, but not all brain regions. These results suggest that inflammation induced by autoimmune disorders may result in neuroinflammation that could result in neurodegeneration. Background: The effects of collagen-induced arthritis (CIA), a model of systemic inflammation, on brain regional molecular markers associated with neurological disorders are uncertain. Objective: This study investigated the brain regional molecular changes in markers associated with inflammation and neuronal dysfunction in a CIA model. Methods: Fourteen male Sprague Dawley rats were divided into control (n = 5) or CIA (n = 9) groups. 10 weeks after CIA induction, brain tissue was collected. Brain regional mRNA expression of inflammatory markers (IL-1β and IL-6), apoptotic markers (BAX and Bcl2) and neurotrophic factors (BDNF, CREB and TrkB) was determined. Monoamine distribution and abundance in different brain regions were determine by mass spectrometry imaging (MSI). Results: Neuroinflammation was confirmed in the CIA group by increased IL-β mRNA expression, concurrent with an increased BAX/Bcl2 ratio. The mRNA expression of CREB was increased in the midbrain and hippocampus while BDNF was increased and TrkB was decreased across all brain regions in CIA compared to control animals. Serotonin was decreased in the midbrain and hippocampus while dopamine was decreased in the striatum of CIA rats, compared to controls. Conclusion: CIA resulted in neuroinflammation concurrent with an apoptotic state and aberrant expression of neurotrophic factors and monoamines in the brain, suggestive of neurodegeneration. [ABSTRACT FROM AUTHOR]

AIM: To investigate the mechanism by which wogonin (WOG) induces ferroptosis in collagen-induced arthritis rat fibroblast-like synoviocytes (rat CIA-FLS cells) through the nuclear factor E2-related factor 2 (NRF2)/heme oxygenase-1 (HO-1) signaling pathway. METHODS: Rat CIA-FLS cells were divided into: control group, low, medium, and high dose of (25, 50 and 100 μmol/L) WOG group, ferroptosis inhibitor (LIP-1) group, LIP-1 + high dose WOG group, HO-1 agonist cobalt protoporphyrin (COPP) group, and COPP + high dose WOG group. CCK-8 assay was used for cell viability. Crystal violet staining was used for for cell morphology. The levels of oxidative stress markers glutathione (GSH), malondialdehyde (MDA), and superoxide dismutase (SOD) were measured. DCFH-DA fluorescent probe was used to detect the intracellular reactive oxygen species (ROS) content as well as Western blot to detect the protein expression levels of Kelch-like ECH-associated protein 1 (KEAP-1), NRF2 and HO-1. RESULTS: Compared with the normal control group, administration of WOG treatment resulted in a significant decrease in CIA-FLS cell viability (P< 0. 01, a significant increase in the level of oxidative stress (P<0. 01), a significant increase in the content of ROS (P< 0. 01), a significant decrease in the level of expression of NRF2 and HO-1 proteins (P<0. 01), and a significant increase in the level of KEAP-1 (P<0. 01) in the rat. Compared with the WOG group, the LIP-1-treated group showed a significant increase in cell viability (P<0. 01, a significant decrease in the level of oxidative stress (P<0. 01), and a significant decrease in the content of ROS (P<0. 01). Compared with the WOG group, the addition of COPP resulted in a significant increase in the protein expression levels of NRF2 and HO-1 (P<0. 01) and a significant decrease in KEAP-1 levels (P< 0.01). CONCLUSION: WOG can induce ferroptosis in rat CIA-FLS cells by promoting oxidative stress through the NRF2/HO-1 signaling pathway. [ABSTRACT FROM AUTHOR]

The characteristic features of the rheumatoid arthritis (RA) microenvironment are synovial inflammation and hyperplasia. Therefore, there is a growing interest in developing a suitable therapeutic strategy for RA that targets the synovial macrophages and fibroblast-like synoviocytes (FLSs). In this study, we used graphene oxide quantum dots (GOQDs) for loading anti-arthritic sinomenine hydrochloride (SIN). By combining with hyaluronic acid (HA)-inserted hybrid membrane (RFM), we successfully constructed a new nanodrug system named HA@RFM@GP@SIN NPs for target therapy of inflammatory articular lesions. Mechanistic studies showed that this nanomedicine system was effective against RA by facilitating the transition of M1 to M2 macrophages and inhibiting the abnormal proliferation of FLSs in vitro. In vivo therapeutic potential investigation demonstrated its effects on macrophage polarization and synovial hyperplasia, ultimately preventing cartilage destruction and bone erosion in the preclinical models of adjuvant-induced arthritis and collagen-induced arthritis in rats. Metabolomics indicated that the anti-arthritic effects of HA@RFM@GP@SIN NPs were mainly associated with the regulation of steroid hormone biosynthesis, ovarian steroidogenesis, tryptophan metabolism, and tyrosine metabolism. More notably, transcriptomic analyses revealed that HA@RFM@GP@SIN NPs suppressed the cell cycle pathway while inducing the cell apoptosis pathway. Furthermore, protein validation revealed that HA@RFM@GP@SIN NPs disrupted the excessive growth of RAFLS by interfering with the PI3K/Akt/SGK/FoxO signaling cascade, resulting in a decline in cyclin B1 expression and the arrest of the G2 phase. Additionally, considering the favorable biocompatibility and biosafety, these multifunctional nanoparticles offer a promising therapeutic approach for patients with RA. [ABSTRACT FROM AUTHOR]

[Display omitted] • PCSK9 exacerbates atrial structural remodeling and promotes AF in collagen-induced arthritis rats by enhancing M1 macrophages polarization. • The PCSK9 is increased in RA patients complicated with AF and the level of PCSK9 is independently associated with AF risk in RA patients. • Evolocumab (a monoclonal antibody of PCSK9) reduces AF susceptibility of rheumatoid arthritis rats. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is implicated in the pathogenesis and progression of autoimmune disease. Patients with rheumatoid arthritis (RA) are at high risk of developing atrial fibrillation (AF), while whether PCSK9 is involved in the onset of AF among RA patients remains unclear. To explore the role of PCSK9 in the occurrence of AF in RA patients and decipher the underlying mechanism. We established a rat model of collagen-induced arthritis (CIA) by immunization with type II collagen in Freund's incomplete adjuvant. Atrial electrophysiological test was used to evaluate AF susceptibility. We performed a clinical study to examine the correlation between PCSK9 level and AF, which recruited healthy control, RA patients and RA patients complicated with AF. Evolocumab (a monoclonal antibody of PCSK9) is administered via intraperitoneal injection in CIA rats to assess the role of PCSK9 in RA-related AF. LPS-RS (LPS inhibitor), clodronate liposomes (depletion of macrophages), and cell co-culture model were used to dissect the mechanism underlying PCSK9 promotes AF. AF inducibility and duration were higher in CIA rats, accompanied by elevated plasma and atrial PCSK9. Interestingly, compared with healthy control subjects, patients with RA showed an increase in PCSK9, and the PCSK9 is much higher in RA patients complicated with AF. The level of PCSK9 was independently associated with AF risk in RA patients. In the in vivo experiment, evolocumab reduced AF susceptibility, and ameliorated atrial structural remodeling of CIA rats. Mechanistically, augmented LPS in CIA rats led to an increase in PCSK9, which exacerbated fibrosis of cardiac fibroblasts and apoptosis of cardiac myocytes by enhancement of M1 macrophages polarization and inflammation, thereby contributing to AF. This study suggests that elevated PCSK9 causes atrial structural remodeling by enhancement of M1 macrophages polarization in atria, and evolocumab can effectively protects CIA rats from AF. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune disease that significantly impacts quality of life by disrupting CD4+ T cell immune homeostasis. The identification of a low-side-effect drug for RA treatment is urgently needed. Our previous study suggests that Trichinella spiralis paramyosin (Ts-Pmy) has immunomodulatory effects, but its potential effect on CD4+ T cell response in RA remains unclear. In this study, we used a murine model to investigate the role of rTs-Pmy in regulating CD4+ T cell differentiation in collagen-induced arthritis (CIA). Additionally, we assessed the impact of rTs-Pmy on CD4+ T cell differentiation towards the Th1 and Th17 phenotypes, which are associated with inflammatory responses in arthritis, using in vitro assays. The results demonstrated that rTs-Pmy administration reduced arthritis severity by inhibiting Th1 and Th17 response while enhancing Treg response. Prophylactic administration of Ts-Pmy showed superior efficacy on CIA compared to therapeutic administration. Furthermore, in vitro assays demonstrated that rTs-Pmy could inhibit the differentiation of CD4+ T cells into Th1 and Th17 while inducing the production of Tregs, suggesting a potential mechanism underlying its therapeutic effects. This study suggests that Ts-Pmy may ameliorate CIA by restoring the immune balance of CD4+ T cells and provides new insights into the mechanism through which helminth-derived proteins exert their effects on autoimmune diseases. [ABSTRACT FROM AUTHOR]

Background: Although various anti-inflammatory medicines are widely recommended for osteoarthritis (OA) treatment, no significantly clinical effect has been observed. This study aims to examine the effects of vitamin B6, a component that has been reported to be capable of alleviating inflammation and cell death in various diseases, on cartilage degeneration in OA. Methods: Collagen-induced arthritis (CIA) mice model were established and the severity of OA in cartilage was determined using the Osteoarthritis Research Society International (OARSI) scoring system. The mRNA and protein levels of indicators associated with extracellular matrix (ECM) metabolism, apoptosis and inflammation were detected. The effect of vitamin B6 (VB6) on the mice were assessed using HE staining and masson staining. The apoptosis rate of cells was assessed using TdT-mediated dUTP nick end labeling. Results: Our results showed a trend of improved OARSI score in mice treated with VB6, which remarkably inhibited the hyaline cartilage thickness, chondrocyte disordering, and knees hypertrophy. Moreover, the VB6 supplementation reduced the protein expression of pro-apoptosis indicators, including Bax and cleaved caspase-3 and raised the expression level of anti-apoptosis marker Bcl-2. Importantly, VB6 improved ECM metabolism in both in vivo and in vitro experiments. Conclusions: This study demonstrated that VB6 alleviates OA through regulating ECM metabolism, inflammation and apoptosis in chondrocytes and CIA mice. The findings in this study provide a theoretical basis for targeted therapy of OA, and further lay the theoretical foundation for studies of mechanisms of VB6 in treating OA. [ABSTRACT FROM AUTHOR]

The primary emphasis of photoimmunology is the impact of nonionizing radiation on the immune system. With the development of terahertz (THz) and sub-terahertz (sub-THz) technology, the biological effects of this emerging nonionizing radiation, particularly its influence on immune function, remain insufficiently explored but are progressively attracting attention. Here, we demonstrated that 0.1 sub-THz radiation can modulate the immune system and alleviate symptoms of arthritis in collagen-induced arthritis (CIA) mice through a nonthermal manner. The application of 0.1 sub-THz irradiation led to a decrease in proinflammatory factors within the joints and serum, reducing the levels of blood immune cells and the quantity of splenic CD4+ T cells. Notably, 0.1 sub-THz irradiation restored depleted Treg cells in CIA mice and re-established the Th17/Treg equilibrium. These findings suggested that sub-THz irradiation plays a crucial role in systemic immunoregulation. Further exploration of its immune modulation mechanisms revealed the anti-inflammatory properties of 0.1 sub-THz on LPS-stimulated skin keratinocytes. Through the reduction in NF-κB signaling and NLRP3 inflammasome activation, 0.1 sub-THz irradiation effectively decreased the production of inflammatory factors and immune-active substances, including IL-1β and PGE2, in HaCaT cells. Consequently, 0.1 sub-THz irradiation mitigated the inflammatory response and contributed to the maintenance of immune tolerance in CIA mice. This research provided significant new evidence supporting the systemic impacts of 0.1 sub-THz radiation, particularly on the immune system. It also enhanced the field of photoimmunology and offered valuable insights into the potential biomedical applications of 0.1 sub-THz radiation for treating autoimmune diseases. [ABSTRACT FROM AUTHOR]

Dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) has been found to be beneficial in rodent rheumatoid arthritis models and human trials. However, the molecular targets of n-3 PUFAs and their beneficial effects on rheumatoid arthritis are under-researched. Free fatty acid receptor 4 (FFA4, also known as GPR120) is a receptor for n-3 PUFA. We aim to investigate whether FFA4 activation reduces collagen-induced rheumatoid arthritis (CIA) by using an FFA4 agonist, compound A (CpdA), in combination with DBA-1J Ffa4 gene wild-type (WT) and Ffa4 gene knock-out (KO) mice. CIA induced an increase in the arthritis score, foot edema, synovial hyperplasia, pannus formation, proteoglycan loss, cartilage damage, and bone erosion, whereas the administration of CpdA significantly suppressed those increases in Ffa4 WT mice but not Ffa4 gene KO mice. CIA increased mRNA expression levels of pro-inflammatory Th1/Th17 cytokines, whereas CpdA significantly suppressed those increases in Ffa4 WT mice but not Ffa4 gene KO mice. CIA induced an imbalance between Th1/Th17 and Treg cells, whereas CpdA rebalanced them in spleens from Ffa4 WT mice but not Ffa4 gene KO mice. In SW982 synovial cells, CpdA reduced the LPS-induced increase in pro-inflammatory cytokine levels. In summary, the present results suggest that the activation of FFA4 in immune and synovial cells could suppress the characteristics of rheumatoid arthritis and be an adjuvant therapy. [ABSTRACT FROM AUTHOR]

Introduction: Triptolide (TP), a natural product derived from the herbal medicine Tripterygium wilfordii, exhibits potent immunosuppressive activity. However, the mechanisms underlying its effects in rheumatoid arthritis remain incompletely understood. Methods: Collagen‐induced arthritis (CIA) model was induced in Sprague−Dawley rats by immunization with bovine type II collagen, and TP was administrated as treatment. The therapeutic effect of TP was evaluated based on paw swelling, histopathology, and serum levels of inflammatory factors. Exosomes isolated from rat serum were characterized by transmission electron microscopy, dynamic light scattering, and western blot analysis. Proteomic profiling of exosomes was analyzed by direct DIA quantitative proteomics analysis. Gene ontology and the Kyoto Encyclopedia of Genes and Genomes databases were employed for enrichment analysis related to molecular function, biological processes, and signaling pathways. Western blot analysis was used to analyze differentially expressed proteins. Results: TP treatment ameliorated arthritic phenotypes in CIA rats as evidenced by reduced arthritis score, paw swelling, pathological injury severity scores, and serum levels of inflammatory cytokines. The proteomic analysis revealed that TP treatment significantly inhibited complement and coagulation cascades, interleukin‐17 signaling pathway, and cholesterol metabolism, which were reactivated in CIA rats. Importantly, lipocalin 2 (LCN2) and myeloperoxidase (MPO) levels were markedly upregulated in the CIA group but suppressed upon TP administration. Furthermore, in synovial tissues, LCN2 and MPO expression levels were also elevated in the CIA group but decreased following TP treatment. Conclusion: Our findings demonstrate that TP alleviates CIA, possibly through modulation of exosomal LCN2 and MPO proteins. [ABSTRACT FROM AUTHOR]

Callicarpa kwangtungensis Chun (CK) is a common remedy exhibits anti-inflammatory properties and has been used in Chinese herbal formulations, such as KangGongYan tablets. It is the main component of KangGongYan tablets, which has been used to treat chronic cervicitis caused by damp heat, red and white bands, cervical erosion, and bleeding. However, the anti-inflammatory effects of CK water extract remains unknown. This study assessed the anti-inflammatory effects of CK in vivo and in vitro, characterized its main components in the serum of rats and verified the anti-inflammatory effects of serum containing CK. Nitric oxide (NO), tumour necrosis factor α (TNF-α) and interleukin-6 (IL-6) release by RAW264.7 cells was examined by ELISA and Griess reagents. Inflammation-related protein expression in LPS-stimulated RAW264.7 cells was measured by western blotting. Furthermore, rat model of foot swelling induced by λ-carrageenan and a collagen-induced arthritis (CIA) rat model were used to explore the anti-inflammatory effects of CK. The components of CK were characterized by LC–MS, and the effects of CK-containing serum on proinflammatory factors levels and the expression of inflammation-related proteins were examined by ELISA, Griess reagents and Western blotting. CK suppressed IL-6, TNF-α, and NO production, and iNOS protein expression in LPS-stimulated RAW264.7 cells. Mechanistic studies showed that CK inhibited the phosphorylation of ERK, P38 and JNK in the MAPK signaling pathway, promoted the expression of IκBα in the NF-κB signaling pathway, and subsequently inhibited the expression of iNOS, thereby exerting anti-inflammatory effects. Moreover, CK reduced the swelling rates with λ-carrageenan induced foot swelling, and reduced the arthritis score and incidence in the collagen-induced arthritis (CIA) rat model. A total of 68 compounds in CK water extract and 31 components in rat serum after intragastric administration of CK were characterized. Serum pharmacological analysis showed that CK-containing serum suppressed iNOS protein expression and NO, TNF-α, and IL-6 release. CK may be an anti-inflammatory agent with therapeutic potential for acute and chronic inflammatory diseases, especially inflammatory diseases associated with MAPK activation. [ABSTRACT FROM AUTHOR]

Background: Macrophages are key inflammatory immune cells that orchestrate the initiation and progression of autoimmune diseases. The characters of macrophage in diseases are determined by its phenotype in response to the local microenvironment. Ficolins have been confirmed as crucial contributors to autoimmune diseases, with Ficolin-2 being particularly elevated in patients with autoimmune diseases. However, whether Ficolin-A stimulates macrophage polarization is still poorly understood. Methods: We investigated the transcriptomic expression profile of murine bone marrow-derived macrophages (BMDMs) stimulated with Ficolin-A using RNA-sequencing. To further confirm a distinct phenotype activated by Ficolin-A, quantitative RT-PCR and Luminex assay were performed in this study. Additionally, we assessed the activation of underlying cell signaling pathways triggered by Ficolin-A. Finally, the impact of Ficolin-A on macrophages were investigated in vivo through building Collagen-induced arthritis (CIA) and Dextran Sulfate Sodium Salt (DSS)-induced colitis mouse models with Fcna-/- mice. Results: Ficolin-A activated macrophages into a pro-inflammatory phenotype distinct to LPS-, IFN-γ- and IFN-γ + LPS-induced phenotypes. The transcriptomic profile induced by Ficolin-A was primarily characterized by upregulation of interleukins, chemokines, iNOS, and Arginase 1, along with downregulation of CD86 and CD206, setting it apart from the M1 and M2 phenotypes. The activation effect of Ficolin-A on macrophages deteriorated the symptoms of CIA and DSS mouse models, and the deletion of Fcna significantly alleviated the severity of diseases in mice. Conclusion: Our work used transcriptomic analysis by RNA-Seq to investigate the impact of Ficolin-A on macrophage polarization. Our findings demonstrate that Ficolin-A induces a novel pro-inflammatory phenotype distinct to the phenotypes activated by LPS, IFN-γ and IFN-γ + LPS on macrophages. [ABSTRACT FROM AUTHOR]

Epstein–Barr virus (EBV) DNA is known to be shed upon reactivation of latent EBV. Based on our previous findings linking Toll-like receptor-9 (TLR9) to an EBV DNA-driven surge in IL-17A production, we aimed to examine the therapeutic potential of TLR9 inhibition in EBV DNA-exacerbated arthritis in a collagen-induced arthritis (CIA) mouse model. C57BL/6J mice were administered either collagen, EBV DNA + collagen, EBV DNA + collagen + TLR9 inhibitor, or only the TLR9 inhibitor. After 70 days, paw thicknesses, clinical scores, and gripping strength were recorded. Moreover, affected joints, footpads, and colons were histologically scored. Furthermore, the number of cells co-expressing IL-17A, IFN-γ, and FOXP3 in joint sections was determined by immunofluorescence assays. Significantly decreased paw thicknesses, clinical scores, and histological scores with a significantly increased gripping strength were observed in the group receiving EBV DNA + collagen + TLR9 inhibitor, compared to those receiving EBV DNA + collagen. Similarly, this group showed decreased IL-17A+ IFN-γ+, IL-17A+ FOXP3+, and IL-17A+ IFN-γ+ FOXP3+ foci counts in joints. We show that inhibiting TLR9 limits the exacerbation of arthritis induced by EBV DNA in a CIA mouse model, suggesting that TLR9 could be a potential therapeutic target for rheumatoid arthritis management in EBV-infected individuals. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Stem cell therapy stands out as a promising avenue for addressing arthritis treatment. However, its therapeutic efficacy requires further enhancement. In this study, we investigated the anti-arthritogenic potential of human amniotic mesenchymal stem cells (AMM) overexpressing insulin-like growth factor 1 (IGF-1) in a collagen-induced mouse model. The IGF-1 gene was introduced into the genome of AMM through transcription activator-like effector nucleases (TALENs). We assessed the in vitro immunomodulatory properties and in vivo anti-arthritogenic effects of IGF-1-overexpressing AMM (AMM/I). Co-culture of AMM/I with interleukin (IL)-1β-treated synovial fibroblasts significantly suppressed NF-kB levels. Transplantation of AMM/I into mice with collagen-induced arthritis (CIA) led to significant attenuation of CIA progression. Furthermore, AMM/I administration resulted in the expansion of regulatory T-cell populations and suppression of T-helper-17 cell activation in CIA mice. In addition, AMM/I transplantation led to an increase in proteoglycan expression within cartilage and reduced infiltration by inflammatory cells and also levels of pro-inflammatory factors including cyclooxygenase-2 (COX-2), IL-1β, NF-kB, and tumor necrosis factor (TNF)-α. In conclusion, our findings suggest that IGF-1 gene-edited human AMM represent a novel alternative therapeutic strategy for the treatment of arthritis. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic and symmetric in-flammation. Our previous research revealed an imbalance in the gut flora of RA patients and showed that certain gut microbiota can accelerate RA progression by enhancing vitamin C degradation. However, it is unclear whether vitamin C supplementation could improve the gut microbiota to prevent the development of arthritis by interfering with the gut-joint axis. In this work, we aimed to evaluate the effects of vitamin C in regulating the gut microbiota and to elucidate its potential role in the onset and progression of RA in a mouse model, thus providing a basis for the development of new intervention strategies and treatments for RA. In this study, collagen-induced arthritis (CIA) mouse models, biochemical, histological and 16S rRNA microbiological methods were used to investigate the role and possible mechanism of vitamin C in rheumatoid arthritis. The results showed that treatment of CIA mice with vitamin C effectively rescued the gut mi-crobiota imbalance and suppressed the inflammatory response associated with RA, and effectively alleviated arthritis symptoms in mice in which levels of the pro-inflammatory cytokines IL-6 and TNF-α were specifi-cally reduced. In conclusion, our results demonstrate the potential of vitamin C as a potential therapeutic choice for RA. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by excessive inflammation in the joints. Glucocorticoid drugs are used clinically to manage RA symptoms, while their dosage and duration need to be tightly controlled due to severe adverse effects. Using dexamethasone (DEX) as a model drug, we explored here whether peptide-guided delivery could increase the safety and therapeutic index of glucocorticoids for RA treatment. Using multiple murine RA models such as collagen-induced arthritis (CIA), we found that CRV, a macrophage-targeting peptide, can selectively home to the inflammatory synovium of RA joints upon intravenous injection. The expression of the CRV receptor, retinoid X receptor beta (RXRB), was also elevated in the inflammatory synovium, likely being the basis of CRV targeting. CRV-conjugated DEX increased the accumulation of DEX in the inflamed synovium but not in healthy organs of CIA mice. Therefore, CRV-DEX demonstrated a stronger efficacy to suppress synovial inflammation and alleviate cartilage/bone destruction. Meanwhile, CRV conjugation reduced immune-related adverse effects of DEX even after a long-term use. Last, we found that RXRB expression was significantly elevated in human patient samples, demonstrating the potential of clinical translation. Taken together, we provide a novel, peptide-targeted strategy to improve the therapeutic efficacy and safety of glucocorticoids for RA treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Inter-α-trypsin inhibitor heavy chain 4 (ITIH4) is a major protein in serum and reported to be upregulated at the onset of rheumatoid arthritis (RA). Its citrullinated form, cit-ITIH4, is specifically found in the serum and synovial fluid of patients with RA. However, the detailed function of ITIH4 in arthritis remains unknown. The aim of this study was to clarify the role of ITIH4 and cit-ITIH4 using experimental arthritis models. ITIH4 and cit-ITIH4 expression was examined in steady-state mice and two different arthritis models, and their pathological effects were examined in Itih4-deficient mice. In naïve C57BL/6 (WT) mice, ITIH4 was expressed as mRNA in the liver and the lung and was expressed as protein in serum and hepatocytes. In K/BxN serum transferred arthritis (K/BxN-STA) and collagen-induced arthritis (CIA), ITIH4 and cit-ITIH4 in sera were increased before the onset of arthritis, and cit-ITIH4 was further increased at the peak of arthritis. In Itih4-deficient mice, citrullinated proteins in serum and joints, especially 120 kDa protein, were clearly diminished; however, there was no significant difference in arthritis severity between WT and itih−/− mice either in the K/BxN-STA or CIA model. CIA mice also exhibited pulmonary lesions and itih4−/− mice tended to show enhanced inflammatory cell aggregation compared to WT mice. Neutrophils in the lungs of itih4−/− mice were significantly increased compared to WT mice. In summary, ITIH4 itself did not alter the severity of arthritis but may inhibit autoimmune inflammation via suppression of neutrophil recruitment. ITIH4 and cit-ITIH4 in sera of K/BxN-STA and CIA were increased before the onset of arthritis, and cit-ITIH4 was further increased at the peak of arthritis. CIA mice also exhibited pulmonary lesions and itih4−/− mice tended to show enhanced inflammatory cell aggregation compared to WT mice. Neutrophils in the lungs of itih4−/− mice were significantly increased compared to WT mice. Graphical Abstract [ABSTRACT FROM AUTHOR]

Objective: Fibroblast-like synoviocytes (FLS) play a critical role on the exacerbation and deterioration of rheumatoid arthritis (RA). Aberrant activation of FLS pyroptosis signaling is responsible for the hyperplasia of synovium and destruction of cartilage of RA. This study investigated the screened traditional Chinese medicine berberine (BBR), an active alkaloid extracted from the Coptis chinensis plant, that regulates the pyroptosis of FLS and secretion of inflammatory factors in rheumatoid arthritis. Methods: First, BBR was screened using a high-throughput drug screening strategy, and its inhibitory effect on RA-FLS was verified by in vivo and in vitro experiments. Second, BBR was intraperitoneally administrated into the collagen-induced arthritis rat model, and the clinical scores, arthritis index, and joint HE staining were evaluated. Third, synovial tissues of CIA mice were collected, and the expression of NLRP3, cleaved-caspase-1, GSDMD-N, Mst1, and YAP was detected by Western blot. Results: The administration of BBR dramatically alleviated the severity of collagen-induced arthritis rat model with a decreased clinical score and inflammation reduction. In addition, BBR intervention significantly attenuates several pro-inflammatory cytokines (interleukin-1β, interleukin-6, interleukin-17, and interleukin-18). Moreover, BBR can reduce the pyroptosis response (caspase-1, NLR family pyrin domain containing 3, and gasdermin D) of the RA-FLS in vitro, activating the Hippo signaling pathway (Mammalian sterile 20-like kinase 1, yes-associated protein, and transcriptional enhanced associate domains) so as to inhibit the pro-inflammatory effect of RA-FLS. Conclusion: These results support the role of BBR in RA and may have therapeutic implications by directly repressing the activation, migration of RA-FLS, which contributing to the attenuation of the progress of CIA. Therefore, targeting PU.1 might be a potential therapeutic approach for RA. Besides, BBR inhibited RA-FLS pyroptosis by downregulating of NLRP3 inflammasomes (NLRP3, caspase-1) and eased the pro-inflammatory activities via activating the Hippo signaling pathway, thereby improving the symptom of CIA. Key Points • The administration of berberine (BBR) dramatically alleviated the severity of CIA model with a decreased clinic score and joint inflammation. • BBR inhibited the pyroptosis of RA-FLS by downregulating of NLRP3 inflammasomes and activating the Hippo signaling pathway, contributing to the suppression of RA progress. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study is to investigate whether fat mass and obesity-associated protein (FTO) and NOL1/NOP2/Sun domain family member 2 (NSUN2) mediated RNA methylation is associated with RA pathology. Methods: We studied the anti-rheumatoid arthritis (RA) mechanism mediated by FTO and NSUN2 in RA samples and collagen-induced arthritis (CIA) rats using real time qPCR (RT-qPCR), western blot, immunofluorescence, and other methods. Key findings: The expression of NSUN2 was significantly increased in both RA patients and CIA rats compared with normal controls. Knockdown of NSUN2 blocked the Wnt/β-catenin signaling pathway and inhibited RA pathological factors such as MMP3, fibronectin, and interleukins. FTO overexpression inhibited RA by inhibiting the expression of NSUN2, up-regulating the level of SFRP1 protein, and blocking the Wnt/β-catenin signaling pathway. NSUN2 overexpression interfered with the inhibitory effects of FTO on the Wnt/β-catenin signaling pathway and RA pathology, which further verified that FTO inhibited RA through the NSUN2/SFRP1/Wnt/β-catenin signal axis. Conclusions: FTO and NSUN2 are important factors of RA, and this work provides new potential diagnostic biomarkers and therapeutic targets for RA. We also reveal a gene expression regulation pattern of the interaction between m6A and m5C. revealing the pathogenesis of RA from the perspective of RNA methylation. FTO inhibits RA pathology through the NSUN2/SFRP1/Wnt/β-catenin signal axis. The expression of NSUN2 was significantly increased in RA compared with control. NSUN2 knockdown reduced the level of β-catenin in RA FLS, inhibited the entry of β-catenin into the nucleus of FLS, and down-regulated the expression of c-Myc and CCND1. Knockdown of NSUN2 inhibited the expression of RA related MMP3, fibronectin and interleukins. The expression of FTO is reduced in RA, and the FTO inhibited RA by inhibiting the expression of NSUN2, up-regulating the level of SFRP1 protein and blocking the Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

Background: Recent therapeutic-plasmid DNA vaccine strategies for rheumatoid arthritis (RA) have significantly improved. Our pcDNA-CCOL2A1 vaccine is the most prominent and the first antigen-specific tolerising DNA vaccine with potent therapeutic and prophylactic effects compared with methotrexate (MTX), the current "gold standard" treatment for collagen-induced arthritis (CIA). This study developed a highly efficient, cost-effective, and easy-to-operate system for the lab-scale production of endotoxin-free supercoiled plasmids with high quality and high yield. Based on optimised fermentation culture, we obtained a high yield of pcDNA-CCOL2A1 vaccine by PEG/MgCl2 precipitation and TRION-114. We then established a method for quality control of the pcDNA-CCOL2A1 vaccine. Collagen-induced arthritis (CIA) model rats were subjected to intramuscular injection of the pcDNA-CCOL2A1 vaccine (300 μg/kg) to test its biological activity. Results: An average yield of 11.81 ± 1.03 mg purified supercoiled plasmid was obtained from 1 L of fermentation broth at 670.6 ± 57.42 mg/L, which was significantly higher than that obtained using anion exchange column chromatography and a commercial purification kit. Our supercoiled plasmid had high purity, biological activity, and yield, conforming to the international guidelines for DNA vaccines. Conclusion: The proposed innovative downstream process for the pcDNA-CCOL2A1 vaccine can not only provide a large-scale high-quality supercoiled plasmid DNA for preclinical research but also facilitate further pilot-scale and even industrial-scale production of pcDNA-CCOL2A1 vaccine. [ABSTRACT FROM AUTHOR]

Lignan-rich beans, nuts, and various seeds are the main foods with antioxidative and hormone-modulating activities. Although the role of lignans in mediating hormone-dependent cancers and cardiovascular diseases is well characterized, the function of lignans in anti-arthritic activity and its underlying mechanisms remain unknown. Three new lignan derivatives, (-)-nortrachelogenin, trachelogenin, and matairesinol, were extracted from Loranthus parasiticus. After establishing the collagen-induced arthritis (CIA) model by intradermal injection of collagen, rats were treated with three new lignan derivatives ((-)-nortrachelogenin: 37%; trachelogenin: 27%; matairesinol: 25.7%) at a concentration of 50 mg/kg and 100 mg/kg, or methotrexate at 0.3 mg/kg. Mixed lignan derivatives significantly attenuated the immune responses in the joints of CIA rats, leading to lower levels of proinflammatory cytokines (IL-6 and TNF-α) and higher levels of free androgen in the serum compared to the CIA model. The results of molecular docking using AutoDock Vina showed that the lignan derivative (-)-nortrachelogenin was the most effective compound for binding to sex hormone-binding globulin (SHBG), thus inhibiting the activity of NFκB in LPS-stimulated macrophages. In this study, (-)-nortrachelogenin was identified as a novel natural lignan derivative with previously unrecognized anti-inflammatory activity. Its molecular mechanism appears related to the regulation of the NFκB/SHBG pathway. Our findings suggest that further application of sex hormone-like compounds in the treatment of rheumatoid arthritis and the potential clinical applications of (-)-nortrachelogenin are promising. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune disease characterized by a notably high disability rate, primarily attributed to cartilage and bone degradation. The involvement of heat shock protein 90 (HSP90) as a molecular chaperone in the inflammatory response of RA has been established, but its role in bone destruction remains uncertain. In the present study, the expression of HSP90 was augmented in osteoclasts induced by the receptor activator of nuclear factor-κB ligand. Additionaly, it was observed that the outcomes revealed a noteworthy inhibition of osteoclast formation and differentation when triptolide was utilized to hinder the expression of HSP90. Furthermore, the positive influence of HSP90 in osteoclast differentiation was substantiated by overexpressing HSP90 in osteoclast precursor cells. Mechanically, HSP90 significantly activated the TNF receptor-associated factor 6 (TRAF6)/Nuclear factor of activated T cells 1 (NFATc1) signaling axis, accompanied by markedly promoting osteoclast differentiation. This effect was consistently observed in the destructive joint of rats with collagen-induced arthritis, where HSP90 effectively activated osteoclasts and contributed to arthritic bone destruction by activating the TRAF6/NFATc1 signaling. Overall, the findings of this study provide compelling evidence that HSP90 exacerbates bone destruction in RA by promoting osteoclast differentiation through the activation of TRAF6/NFATc1 signaling, and interference with HSP90 may be a promising strategy for the discovery of anti-arthritic bone destruction agents. [ABSTRACT FROM AUTHOR]

Dickkopf-1 (DKK-1) has been considered a master regulator of bone remodeling. As precursors of osteoclasts (OCs), myeloid-derived suppressor cells (MDSCs) were previously shown to participate in the process of bone destruction in rheumatoid arthritis (RA). However, the role of DKK-1 and MDSCs in RA is not yet fully understood. We investigated the relevance between the level of DKK-1 and the expression of MDSCs in different tissues and joint destruction in RA patients and collagen-induced arthritis (CIA) mouse models. Furthermore, the CIA mice were administered recombinant DKK-1 protein. The arthritis scores, bone destruction, and the percentage of MDSCs in the peripheral blood and spleen were monitored. In vitro, the differentiation of MDSCs into OCs was intervened with recombinant protein and inhibitor of DKK-1. The number of OCs differentiated and the protein expression of the Wnt/β-catenin signaling pathway were explored. The level of DKK-1 positively correlates with the frequency of MDSCs and bone erosion in RA patients and CIA mice. Strikingly, recombinant DKK-1 intervention significantly exacerbated arthritis scores and bone destruction, increasing the percentage of MDSCs in the peripheral blood and spleen in CIA mice. In vitro experiments showed that recombinant DKK-1 promoted the differentiation of MDSCs into OCs, reducing the expression of β-catenin and TCF4 and increasing the expression of CyclinD1. In contrast, the DKK-1 inhibitor had the opposite effect. Our findings highlight that DKK-1 promoted MDSCs expansion in RA and enhanced the differentiation of MDSCs into OCs via targeting the Wnt/β-catenin pathway, aggravating the bone destruction in RA. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial tissue inflammation, substantially impacting the quality of life of patients. The interaction between L-selectin and its glycoprotein ligands modified with 6-sulfo sialyl Lewis x (6-sulfo sLex) is known to mediate lymphocyte homing to initiate immune responses. Thus, this process could be a potential therapeutic target for RA. Herein, we explored the preventive effects of an anti-6-sulfo sLex monoclonal antibody (mAb), SF1, on collagen-induced arthritis (CIA) in DBA/1 mice. Mice were administered SF1 from day 21 postfirst immunization with type II collagen (CII), and the effects of SF1 on both clinical and histopathological disease progression evoked by the second immunization were examined. SF1 significantly suppressed clinical features and histological levels associated with arthritis severity. Enzyme-linked immunosorbent assay consistently indicated that SF1 inhibited the production of CII-specific IgG2a. Based on the reverse transcription-quantitative PCR analysis, SF1 suppressed the expression of interferon-γ, a T helper 1 cytokine, as well as that of inflammatory cytokines, including tumor necrosis factor-α and interleukin-1β, in draining lymph nodes. Collectively, these results indicate that SF1, an anti-sulfated glycan mAb, could be beneficial in preventing CIA in mice and may afford as a novel agent to treat RA. [ABSTRACT FROM AUTHOR]

All-trans retinoic acid (ATRA) has emerged as a promising adjunctive treatment for rheumatoid arthritis. However, the mechanism by which ATRA mitigates arthritis remains unclear. In this study, we aimed to explore ATRA alleviation of arthritis and the role of ATRA in regulating intestinal homeostasis. Thus, we established a collagen-induced arthritis (CIA) model in Wistar rats. After 6 weeks of ATRA treatment, the arthritis index of CIA rats decreased, synovial inflammation was alleviated, and the disruption of Th17/Treg differentiation in peripheral blood was reversed. Additionally, the Th17/Treg ratio in the mesenteric lymph nodes decreased and the expression of Foxp3 mRNA increased and that of IL-17 mRNA decreased in the colon and ileum. Microscopically, we observed reduced intestinal inflammation. Transmission electron microscopy revealed that ATRA could repair tight junctions, which was accompanied by an increase in the expression of Claudin-1, Occludin and ZO-1. Moreover, ATRA regulated the composition of the gut microbiota, as was characterized based on the reduced abundance of Desulfobacterota and the increased abundance of Lactobacillus. In conclusion, ATRA demonstrates the potential to alleviate arthritis in CIA rats, which might be correlated with modulating the gut microbiota and regulating the intestinal immune response. Our findings provide novel insights into ATRA-mediated alleviation of arthritis. [ABSTRACT FROM AUTHOR]

BACKGROUND: In clinical practice, Cibotium barometz and Epimedium have shown significant efficacy in the treatment of rheumatoid arthritis, but the complex active ingredients contained in the two have an unclear mechanism of action at the molecular level for the treatment of rheumatoid arthritis. OBJECTIVE: Based on network pharmacology and molecular docking technology, to establish a collagen-induced arthritis model and to verify the potential targets and pathways of Cibotium barometz and Epimedium in the treatment of rheumatoid arthritis, providing reliable experimental evidence for the use of clinical formulas with Cibotium barometz and Epimedium as the main components. METHODS: Utilizing traditional Chinese medicine research platforms, traditional Chinese medicine encyclopedias, and databases of traditional Chinese medicine and chemical components from the Shanghai Institute of Organic, effective ingredients were retrieved and identified. 3D molecular formulas were obtained from the PubChem platform and target predictions were made using PharmMapper and SwissTargetPrediction. Disease targets for rheumatoid arthritis were obtained from gene databases such as DrugBank, GeneCards, and OMIM. The intersections of targets and Cibotium barometz and Epimedium were plotted using VENNY 2.1 after calibration with the Uniport database. A protein-protein interaction network graph was constructed using the STRING platform. Gene Ontology function analysis and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were performed using the Metascape platform for data visualization. A four-layered network model of traditional Chinese medicine, ingredients, targets, diseases, and pathways was constructed using Cytoscape 3.9.0. The main effective ingredients were docked with core targets using AutoDock-Vina software to explore the best binding targets. A type II collagen+adjuvant-induced arthritis rat model was established, and the effects of Cibotium barometz and Epimedium on relevant pathway targets and inflammatory cell factors were observed after 21 days of intervention. RESULTS AND CONCLUSION: A total of 28 active ingredients from Cibotium barometz and Epimedium were selected, yielding 288 intersection targets for rheumatoid arthritis. The main ingredients included isobavachalcone, cibotium, and epimedium. The main targets included protein kinase 1 for serine/ threonine (AKT1), tumor necrosis factor, and vascular endothelial growth factor A. Gene ontology analysis yielded 2 232 biological processes, mainly related to serine protein phosphorylation, positive regulation of serine/threonine protein kinase, and reactive oxygen metabolism. Kyoto Encyclopedia of Genes and Genomes enrichment analysis yielded 202 pathways, mainly involving the PI3K/AKT signaling pathway and epidermal growth factor receptor signaling pathway, which may exert therapeutic effects by regulating synovial cell apoptosis and proliferation and suppressing inflammatory factors. Molecular docking results showed the strongest binding activity and stable structure of Cibotium barometz and Epimedium with AKT1 and estrogen receptor transcription factor 1, which was closely related to apoptosis and proliferation and inflammatory signaling pathways such as PI3K/AKT. Cibotium barometz and Epimedium reduced the expression of interleukin-1β, interleukin-6, and tumor necrosis factor-α in the serum of collagen-induced arthritis rat models. Cibotium barometz and Epimedium reduced the expression of p-PI3K, p-AKT, and p-FOXO1 in the synovium of collagen-induced arthritis rat models. The results indicate that the combination of Cibotium barometz and Epimedium may exert therapeutic effects by inhibiting the proliferation of synovial cells and suppressing the expression of inflammatory factors via the PI3K/AKT/FOXO1 signaling pathway. This may be closely related to the occurrence of inflammation and bone destruction in rheumatoid arthritis, and provides a reference for the rational use and development of new drugs in clinical practice. [ABSTRACT FROM AUTHOR]

Objective To study the effects of Guizhi Shaoyao Zhimu Decoction on factors related to bone destruction and bone protection in rats with collagen-induced arthritis (CIA) based on osteoprotegerin (OPG)/receptor activator of NF-?B ligand (RANKL)/receptor activator of NF-?B (RANK) signaling pathway. Methods According to the body weight, 60 female Wistar rats were randomly divided into the following six groups: the normal group, the model group, the Triperygium wilfordii multiglucoside group (0.01 g/kg), the Guizhi Shaoyao Zhimu Decoction low-dose group (8.6 g/kg), the Guizhi Shaoyao Zhimu Decoction medium-dose group (17.2 g/kg), and the Guizhi Shaoyao Zhimu Decoction high-dose group (34.4 g/kg) (n=10 rats per group). The rats in all groups except for the normal group were given 100 µg bovine type II collagen on the 1st and 8th days to establish the CIA model, and was injected into the left foot sole and tail root of the rats. After the successful modeling, the rats were treated by gavage for 4 weeks. The general state, body weight, and arthritis index (AI) score of rats were recorded, and the contents of RANKL and OPG in rat serum were determined by enzyme-linked immunosorbent assay. The mRNA and protein expressions of RANKL, RANK, and OPG in the ankle joint were determined through real-time PCR and Western blotting, respectively. Results Compared with the normal group, the general state of the model group was poor, the toe swelling was obvious, the AI score was increased, the serum RANKL content was increased, the serum OPG content was decreased, and the mRNA and protein expressions of RANKL and RANK in the ankle joint were increased (P<0.05). Compared with the model group, the degree of toe swelling and the AI score of rats in the Guizhi Shaoyao Zhimu Decoction low-, medium-, and high-dose groups were decreased, the serum RANKL content was decreased, the serum OPG content was increased, the mRNA and protein expressions of RANKL and RANK in the ankle joint were decreased, the mRNA and protein expressions of OPG were increased, and the RANKL/OPG ratio of the ankle joint was decreased(P<0.05). Conclusion Guizhi Shaoyao Zhimu Decoction can improve the destruction of joint bone in CIA rats, and its mechanism of action may be related to reducing RANKL level, reducing RANKL/OPG ratio, and regulating bone balance. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis is a systemic autoimmune inflammatory disease that affects millions of people worldwide. There are multiple disease-modifying anti-rheumatic drugs available; however, many patients do not respond to any treatment. A disintegrin and metalloproteinase 10 has been suggested as a potential new target for RA due to its role in the release of multiple pro- and anti-inflammatory factors from cell surfaces. In the present study, we determined the pharmacokinetic parameters and in vivo efficacy of a compound CID3117694 from a novel class of non-zinc-binding inhibitors. Oral bioavailability was demonstrated in the blood and synovial fluid after a 10 mg/kg dose. To test efficacy, we established the collagen-induced arthritis model in mice. CID3117694 was administered orally at 10, 30, and 50 mg/kg/day for 28 days. CID3117694 was able to dose-dependently improve the disease score, decrease RA markers in the blood, and decrease signs of inflammation, hyperplasia, pannus formation, and cartilage erosion in the affected joints compared to the untreated control. Additionally, mice treated with CID 3117694 did not exhibit any clinical signs of distress, suggesting low toxicity. The results of this study suggest that the inhibition of ADAM10 exosite can be a viable therapeutic approach to RA. [ABSTRACT FROM AUTHOR]

Macaques are useful animal models for studying the pathogenesis of rheumatoid arthritis (RA) and the development of anti‐rheumatic drugs. The purpose of this study was to identify the major histocompatibility complex (MHC) polymorphisms associated with the pathology of collagen‐induced arthritis (CIA) and anti‐collagen IgG induction in a cynomolgus macaque model, as MHC polymorphisms affect the onset of CIA in other animal models. Nine female Filipino cynomolgus macaques were immunized with bovine type II collagen (b‐CII) to induce CIA, which was diagnosed clinically by scoring the symptoms of joint swelling over 9 weeks. MHC polymorphisms and anti‐b‐CII antibody titers were compared between symptomatic and asymptomatic macaques. Four of 9 (44%) macaques were defined as the CIA‐affected group. Anti‐b‐CII IgG in the affected group increased in titer approximately 3 weeks earlier compared with the asymptomatic group. The mean plasma IgG1 titer in the CIA‐affected group was significantly higher (p < 0.05) than that of the asymptomatic group. Furthermore, the cynomolgus macaque MHC (Mafa)‐DRB1*10:05 or Mafa‐DRB1*10:07 alleles, which contain the well‐documented RA‐susceptibility five amino acid sequence known as the shared epitope (SE) in positions 70 to 74, with valine at position 11 (Val11, V11) and phenylalanine at position 13 (Phe13, F13), were detected in the affected group. In contrast, no MHC polymorphisms specific to the asymptomatic group were identified. In conclusion, the presence of V11 and F13 along with SE in the MHC‐DRB1 alleles seems essential for the production of IgG1 and the rapid induction of severe CIA in female Filipino cynomolgus macaques. [ABSTRACT FROM AUTHOR]

The primary pathological changes of rheumatoid arthritis (RA) include chronic synovial inflammation, bone destruction, and aggressive pannus formation on cartilage, in which angiogenesis plays a critical role. B7-H3, an important immune checkpoint molecule, represents a novel target in tumor therapy and plays a significant role in the pathogenesis of autoimmune diseases. However, its biological mechanism in RA remains unclear. Hematoxylin-eosin (HE) staining and immunohistochemistry were used to explore the histological characteristics and expression of B7-H3, CD34, and vascular endothelial growth factor (VEGF) in patients with RA and collagen-induced arthritis (CIA) mice. ELISA was used to detect VEGF, soluble B7-H3, and disease markers in the peripheral blood of patients. A monoclonal anti-B7-H3 antibody was used to treat CIA mice by blocking B7-H3-mediated signaling. The ELISA and HE staining results showed a positive correlation between the expression of B7-H3 and the degree of joint cavity destruction and pannus formation. B7-H3 expression also correlated with increased expression of the vessel biomarkers CD34 and VEGF. Anti-B7-H3 effectively reduced pannus formation in CIA mice. B7-H3 modulates angiogenic activity in the joint synovium, demonstrating its therapeutic value in the context of RA. • There was a correlation between B7-H3 expression and the vessel biomarkers. • B7-H3-blocking antibody could reduce pannus formation in CIA mice. • B7-H3 could modulate the ability of angiogenesis. [ABSTRACT FROM AUTHOR]

To evaluate the effect of exosomes secreted by berberine-treated bone marrow-derived mesenchymal stem cells (BMSCs) on synovial inflammation in collagen-induced arthritis (CIA) model. Exosomes were isolated from berberine-treated BMSCs (Ber-BMSC-EXs) and untreated BMSCs (BMSC-EXs). CIA rats were developed and treated with Ber-BMSC-EXs or BMSC-EXs. Clinical arthritis index was measured, activation of fibroblast-like synoviocytes (FLSs) were evaluated, and response and frequency of T helper 17 (Th17) and regulatory T (Treg) cells as well as cytokine levels in synovial fluid were determined. Ber-BMSC-EXs (with a superior effect than BMSC-EXs) significantly alleviated RA clinical score and paw inflammation, balanced Th17 and Treg cells' responses and population, modulated levels of proinflammatory and anti-inflammatory cytokines in joint synovial fluid, and inhibited FLS activation in CIA rats. Ber-BMSC-EXs (with a significantly greater effect than BMSC-EXs) could significantly ameliorate synovial joint inflammation and clinical symptoms of arthritis in CIA rats, showing that berberine can reinforce antiarthritic effects of BMSC-EXs. [ABSTRACT FROM AUTHOR]