Synovial Hyperplasia Research Articles

3D in vitro synovial hyperplasia model on polycaprolactone-micropatterned nanofibrous microwells for screening disease-modifying anti-rheumatic drugs

Rheumatoid arthritis (RA) is known to be caused by autoimmune disorders and can be partially alleviated through Disease-Modifying Antirheumatic Drugs (DMARDs) therapy. However, due to significant variations in the physical environment and condition of each RA patient, the types and doses of DMARDs prescribed can differ greatly. Consequently, there is a need for a platform based on patient-derived cells to determine the effectiveness of specific DMARDs for individual patient. In this study, we established an RA three-dimensional (3D) spheroid that mimics the human body's 3D environment, enabling high-throughput assays by culturing patient-derived synovial cells on a macroscale-patterned polycaprolactone (PCL) scaffold. Fibroblast-like synoviocytes (FLSs) from patient and human umbilical vein endothelial cells (HUVECs) were co-cultured to simulate vascular delivery. Additionally, RA characteristics were identified at both the genetic and cytokine levels using real-time polymerase chain reaction (RT-qPCR) and dot blot assay. The similarities in junctions and adhesion were demonstrated in both actual RA patient tissues and 3D spheroids. The 3D RA spheroid was treated with representative DMARDs, observing changes in reactive oxygen species (ROS) levels, lactate dehydrogenase (LDH) levels, and inflammatory cytokine responses to confirm the varying cell reactions depending on the DMARDs used. This study underscores the significance of the 3D drug screening platform, which can be applied to diverse inflammatory disease treatments as a personalized drug screening system. We anticipate that this platform will become an indispensable tool for advancing and developing personalized DMARD treatment strategies.

Fangji Huangqi Decoction alleviates rheumatoid arthritis through regulating HIF-1α mediated the angiogenesis and the balance between autophagy and apoptosis

Ethnopharmacological relevanceFangji Huangqi Decoction (FHD) is frequently prescribed for the clinical treatment of wind-cold and wind-dampness pathogenic superficial deficiency syndrome. It also has a notable curative effect on rheumatoid arthritis (RA). Aim of the studyThe study aimed to explore the possible mechanism of FHD against RA and provided a theoretical basis for alternative therapies for RA. Materials and methodsWe used UPLC-Q-TOF-MS to analysis the ingredients and absorbed blood components of FHD. At the same time, the collagen-induced arthritis (CIA) rat model was established to estimate the therapeutic effects on FHD by considering body weight, arthritis score, paw swelling, autonomous movement ability, and synovial microvessel counts. Subsequently, immunofluorescence, immunohistochemistry, and Western blot were employed to detect the anti-angiogenic capacity of FHD in vivo, as well as the levels of apoptosis and autophagy in the synovial tissue. In addition, flow cytometry and Western blot were used to assess the effects of FHD on apoptosis and autophagy in MH7A cells. The effects of FHD on the proliferation and migration of MH7A cells were measured by CCK8 assay, cell migration and, invasion experiments. Finally, a tube formation assay was performed to evaluate the angiogenic capacity of FHD in co-cultures of MH7A cells and HUVEC cells. ResultsThrough testing of FHD's original formula, a total of 26 active ingredients have been identified, with 17 of them being absorbed into the bloodstream. FHD significantly improved the pathological symptoms and synovial hyperplasia of CIA rats. FHD could suppress the expression of HIF-1α, promote apoptosis in CIA rat synovial tissue, and suppress autophagy and angiogenesis. In vitro experiments showed that serum containing FHD inhibited the proliferation, migration, and invasion of MH7A cells, and also suppressed the expression of autophagy-related proteins while promoting apoptosis. FHD markedly repressed the expression of HIF-1α protein in TNF-α-stimulated MH7A cells and inhibited the tube formation capacity induced by MH7A cells in HUVEC cells. ConclusionsThe study had proven that FHD played an excellent anti-RA role, which may be attributed to its potential mechanism of regulating the balance between autophagy and apoptosis in RA FLS by suppressing the HIF-1α, thus contributing to its anti-angiogenic activities.

TRPM7 facilitates fibroblast-like synoviocyte proliferation, metastasis and inflammation through increasing IL-6 stability via the PKCα-HuR axis in rheumatoid arthritis

Transient receptor potential melastatin 7 (TRPM7) is a cation channel that plays a role in the progression of rheumatoid arthritis (RA), yet its involvement in synovial hyperplasia and inflammation has not been determined. We previously reported that TRPM7 affects the destruction of articular cartilage in RA. Herein, we further confirmed the involvement of TRPM7 in fibroblast-like synoviocyte (FLS) proliferation, metastasis and inflammation. We observed increased TRPM7 expression in FLSs derived from human RA patients. Pharmacological inhibition of TRPM7 protected primary RA-FLSs from proliferation, metastasis and inflammation. Furthermore, we found that TRPM7 contributes to RA-FLS proliferation, metastasis and inflammation by increasing the intracellular Ca2+ concentration. Mechanistically, the PKCα-HuR axis was demonstrated to respond to Ca2+ influx, leading to TRPM7-mediated RA-FLS proliferation, metastasis and inflammation. Moreover, HuR was shown to bind to IL-6 mRNA after nuclear translocation, which could be weakened by TRPM7 channel inhibition. Additionally, adeno-associated virus 9-mediated TRPM7 silencing is highly effective at alleviating synovial hyperplasia and inflammation in adjuvant-induced arthritis rats. In conclusion, our findings unveil a novel regulatory mechanism involved in the pathogenesis of RA and suggest that targeting TRPM7 might be a potential strategy for the prevention and treatment of RA.

Dual-targeted halofuginone hydrobromide nanocomplexes for promotion of macrophage repolarization and apoptosis of rheumatoid arthritis fibroblast-like synoviocytes in adjuvant-induced arthritis in rats

Rheumatoid arthritis (RA) is a prevalent autoimmune disease characterized by chronic inflammation and excessive proliferation of the synovium. Currently, treatment options focus on either reducing inflammation or inhibiting synovial hyperplasia. However, these modalities are unsatisfactory in achieving the desired therapeutic outcomes. Halofuginone hydrobromide (HF), an herbal active ingredient, has demonstrated pharmacological effects of both anti-inflammation and inhibition of synovial hyperplasia proliferation. However, HF’s medical efficacy is limited due to its poor water solubility, short half-life, and non-target toxicity. In the current study, by using the advantages of nanotechnology, we presented a novel dual-targeted nanocomplex, termed HA-M@P@HF NPs, which consisted of a hyaluronic acid (HA)-modified hybrid membrane (M)-camouflaged poly lactic-co-glycolic acid (PLGA) nanosystem for HF delivery. These nanocomplexes not only overcame the limitations of HF but also achieved simultaneous targeting of inflammatory macrophages and human fibroblast-like synoviocytes-rheumatoid arthritis (HFLS-RA). In vivo experiments demonstrated that these nanocomplexes effectively suppressed immune-mediated inflammation and synovial hyperplasia, safeguarding against bone destruction in rats with adjuvant-induced arthritis (AIA). Remarkable anti-arthritic effects of these nanocomplexes were accomplished through promoting repolarization of M1-to-M2 macrophages and apoptosis of HFLS-RA, thereby offering a promising therapeutic strategy for RA.

Microenvironmental Enzyme-Responsive Methotrexate Modified Quercetin Micelles for the Treatment of Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease involving synovial inflammation and joint destruction. Although therapeutic drugs for RA have some efficacy, they usually cause severe side effects and are expensive. RA is characterized by synovial hyperplasia, intra-articular hypoxia, upregulated expression of matrix metalloproteinases, and excessive accumulation of reactive oxygen species. The adverse microenvironment further aggravates activated macrophage infiltration. Therefore, controlling the microenvironment of diseased tissues and targeting the activated macrophages have become new therapeutic targets in RA patients. Here, microenvironment-targeting micelles (PVGLIG-MTX-Que-Ms) were synthesized using the thin film hydration method. In the inflammatory microenvironment, PVGLIG was cleaved by the highly expressed MMP-2, PEG5000 was eliminated, MTX was exposed, macrophage activation was targeted, and Que enrichment was enhanced. The cytotoxicity, targeting, antioxidant, and anti-inflammatory properties of drug-loaded micelles were tested in vitro. The drug-loaded micelles were used to treat CIA rats. In vivo targeting, expression of serum inflammatory factors, immunohistochemistry of the articular cartilage, and changes in immunofluorescence staining were observed. The developed micelles had a particle size of (89.62 ±1.33) nm and a zeta potential of (-4.9 ±0.53) mV. The IC50 value of PVGLIG-MTX-Que-Ms (185.90 ±6.98) μmol/L was significantly lower than that of free Que (141.10 ±6.39) μmol/L. The synthesized micelles exhibited slow-release properties, low cytotoxicity, strong targeting abilities, and significant anti-inflammatory effects in vitro. In vivo, the drug-loaded micelles accumulated at the joint site for a long time. PVGLIG-MTX-Que-Ms significantly reduced joint swelling, improved bone destruction, and decreased the expression of serum inflammatory factors in CIA rats. The smart-targeting micelles PVGLIG-MTX-Que-Ms with strong targeting, anti-inflammatory, cartilage-protective, and other multiple positive effects are a promising new tool for RA treatment.

Nuciferine alleviates collagen-induced arthritic in rats by inhibiting the proliferation and invasion of human arthritis-derived fibroblast-like synoviocytes and rectifying Th17/Treg imbalance

Rheumatoid arthritis (RA) is a chronic autoimmune disorder marked by persistent synovial inflammation and joint degradation, posing challenges in the development of effective treatments. Nuciferine, an alkaloid found in lotus leaf, has shown promising anti-inflammatory and anti-tumor effects, yet its efficacy in RA treatment remains unexplored. This study investigated the antiproliferative effects of nuciferine on the MH7A cell line, a human RA-derived fibroblast-like synoviocyte, revealing its ability to inhibit cell proliferation, promote apoptosis, induce apoptosis, and cause G1/S phase arrest. Additionally, nuciferine significantly reduced the migration and invasion capabilities of MH7A cells. The therapeutic potential of nuciferine was further evaluated in a collagen-induced arthritis (CIA) rat model, where it markedly alleviated joint swelling, synovial hyperplasia, cartilage injury, and inflammatory infiltration. Nuciferine also improved collagen-induced bone erosion, decreased pro-inflammatory cytokines and serum immunoglobulins (IgG, IgG1, IgG2a), and restored the balance between T helper (Th) 17 and regulatory T cells in the spleen of CIA rats. These results indicate that nuciferine may offer therapeutic advantages for RA by decreasing the proliferation and invasiveness of FLS cells and correcting the Th17/Treg cell imbalance in CIA rats.

Pathological progression of osteoarthritis: a perspective on subchondral bone.

Osteoarthritis (OA) is a degenerative bone disease associated with aging. The rising global aging population has led to a surge in OA cases, thereby imposing a significant socioeconomic burden. Researchers have been keenly investigating the mechanisms underlying OA. Previous studies have suggested that the disease starts with synovial inflammation and hyperplasia, advancing toward cartilage degradation. Ultimately, subchondral-bone collapse, sclerosis, and osteophyte formation occur. This progression is deemed as "top to bottom." However, recent research is challenging this perspective by indicating that initial changes occur in subchondral bone, precipitating cartilage breakdown. In this review, we elucidate the epidemiology of OA and present an in-depth overview of the subchondral bone's physiological state, functions, and the varied pathological shifts during OA progression. We also introduce the role of multifunctional signal pathways (including osteoprotegerin (OPG)/receptor activator of nuclear factor-kappa B ligand (RANKL)/receptor activator of nuclear factor-kappa B (RANK), and chemokine (CXC motif) ligand 12 (CXCL12)/CXC motif chemokine receptor 4 (CXCR4)) in the pathology of subchondral bone and their role in the "bottom-up" progression of OA. Using vivid pattern maps and clinical images, this review highlights the crucial role of subchondral bone in driving OA progression, illuminating its interplay with the condition.

Exploring the Mechanism of Acupuncture's Influence on the Protease Activity and Free Radical Damage in Synovial Fluid of Rheumatoid Arthritis Rats Induced by Type II Collagen from the Release of Active Oxygen.

Acupuncture was studied to investigate the mechanism of its effect on protease vitality and free radical damage in Type I CIA rats induced by type II collagen. The study divided rats into a control group (injected with physiological saline, n = 10), a model group (injected with type II collagen, n = 10), and an intervention group (injected with type II collagen + acupuncture ST36 and GB39, 3 times a week, for a total of 4weeks, n = 10) based on the different injected drugs. Then, various indicators of the mice were experimentally tested using joint index scoring, H&E histological staining, protein blotting, and immunohistochemistry staining methods. Acupuncture ST36 and GB39 can reduce arthritis scores, histological staining scores, and increase MVD in CIA rats. And reduce protease levels, alleviate inflammation, synovial hyperplasia, and angiogenesis. In addition, the intervention group TNF-α, IL-1β and IL-6 mRNA were reduced, and the clearance rates of hydrogen peroxide free radicals and nitric oxide free radicals were increased. The expression levels of ROS and MDA decrease, while the expression levels of SOD increase It has been proved that acupuncture at ST36 and GB39 can inhibit the release of ROS, reduce protease activity, inflammation, synovial hyperplasia, angiogenesis and free radical damage, thus reducing the severity of CIA (Collagen-Induced Arthritis) in rats.

Extracorporeal photopheresis reduces inflammation and joint damage in a rheumatoid arthritis murine model

BackgroundRheumatoid arthritis (RA) is an autoimmune disease characterized by inflammatory reactions and tissue damage in the joints. Long-term drug use in clinical practice is often accompanied by adverse reactions. Extracorporeal photopheresis (ECP) is an immunomodulatory therapy with few side effects, offering a potential and safe therapeutic alternative for RA through the induction of immune tolerance. This study aimed to investigate the therapeutic effects of ECP on RA using a collagen-induced arthritis (CIA) murine model, as well as to explore its immunomodulatory effects in vivo. Additionally, particular attention was given to the significant role of monocytes during the ECP process.MethodsA murine model of rheumatoid arthritis was established by administering two injections of bovine type II collagen to DBA/1J mice. ECP, ECP-MD (mononuclear cells were depleted during the ECP), MTX, and PBS treatment were applied to the CIA mice. During the treatment process, clinical scores and body weight changes of CIA mice were closely monitored. After six treatment sessions, micro-CT images of the hind paws from live mice were captured. Ankle joints and paws of the mice were collected and processed for histological evaluation. Spleen samples were collected to measure the Th17/Treg cells ratio, and serum samples were collected to assess cytokine and anti-type II collagen IgG levels. Monocytes and dendritic cells populations before and after ECP in vitro were detected by flow cytometry.ResultECP therapy significantly attenuated the progression of CIA, alleviated the severity of clinical symptoms in CIA mice and effectively suppressed synovial hyperplasia, inflammation, and cartilage damage. There was an expansion in the percentage of CD3 + CD4 + CD25 + FoxP3 + Tregs and a decrease in CD3 + CD4 + IL17A + Th17 cells in vivo. Furthermore, ECP reduced the serum levels of pro-inflammatory cytokines IL-6 (53.47 ± 7.074 pg/mL vs 5.142 ± 1.779 pg/mL, P < 0.05) and IL-17A (3.077 ± 0.401 pg/mL vs 0.238 ± 0.082 pg/mlL, P < 0.0001) compared with PBS. Interestingly, the depletion of monocytes during the ECP process did not lead to any improvement in clinical symptoms or histological scores in CIA mice. Moreover, the imbalance in the Th17/Treg cells ratio became even more pronounced, accompanied by an augmented secretion of pro-inflammatory cytokines IL-6 and IL-17A. In vitro, compared with cells without ECP treatment, the proportion of CD11b + cells were significantly reduced (P < 0.01), the proportion of CD11c + cells were significantly elevated (P < 0.001) 24 h after ECP treatment. Additionally, the expression of MHC II (P < 0.0001), CD80 (P < 0.01), and CD86 (P < 0.001) was downregulated in CD11c + cells 24 h after ECP treatment.ConclusionOur study demonstrates that ECP exhibits a therapeutic effect comparable to conventional therapy in CIA mice, and the protective mechanisms of ECP against RA involve Th17/Treg cells ratio, which result in decreased IL-6 and IL-17A. Notably, monocytes derived from CIA mice are an indispensable part to the efficacy of ECP treatment, and the proportion of monocytes decreased and the proportion of tolerogenic dendritic cells increased after ECP treatment in vitro.

Vigeo attenuates cartilage and bone destruction in a collagen‑induced arthritis mouse model by reducing production of pro‑inflammatory cytokines.

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by articular cartilage destruction, bone destruction and synovial hyperplasia. It has been suggested that Vigeo, a mixture of Eleutherococcus senticosus, Achyranthes japonica and Atractylodes japonica fermented with Korean nuruk, has an anti-osteoporotic effect in a mouse model of inflammation-mediated bone loss. The present study evaluated the therapeutic effects of Vigeo in RA using a collagen-induced arthritis (CIA) mouse model. DBA/1J mice were immunized with bovine type II collagen on days 0 and 21 and Vigeo was administered daily for 20 days beginning the day after the second type II collagen injection. The mice were sacrificed on day 42 and the joint tissues were anatomically separated and subjected to micro computed tomography and histological analyses. In addition, the serum levels of TNF-α, IL-6 and IL-1β were determined by enzyme-linked immunosorbent assays. CIA in DBA/1J mice caused symptoms of RA, such as joint inflammation, cartilage destruction and bone erosion. Treatment of CIA mice with Vigeo markedly decreased the symptoms and cartilage pathology. In addition, radiological and histological analyses showed that Vigeo attenuated bone and cartilage destruction. The serum TNF-α, IL-6 and IL-1β levels following oral Vigeo administration were also reduced when compared with those in CIA mice. The present study revealed that Vigeo suppressed arthritis symptoms in a CIA-RA mouse model, including bone loss and serum levels of TNF-α, IL-6 and IL-1β.

To Carry Out Anti-Arthritic Activity of Combination of Quercetin and Curcumin Using FCA (Freund’s Complete Adjuvant) Induced Arthritis in Laboratory Rats

To investigate anti-arthritic activity of Quercetin and Curcumin in Freund's complete adjuvant (FCA)-induced arthritis in rats. AA was induced by injecting with Freund's complete adjuvant (FCA). Rats were randomly divided into six groups with 10 mice in each group: (1) Normal group (saline), (2) Vehicle control, (3) Leflunomide (LF, 10 mg/kg), (4) Curcumin (80), (5) Quercetin (40), (6) Curcumin (80) + Quercetin (40). Male SD rats were subjected to treatment with Lut at 10 mg/kg from days 18 to 24 after immunization. Arthritic scores, tumor necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), paw histopathology and the proteins of P2X4 pathway were assessed at the end of the experiment. Lut reduced the severity of arthritic scores during the experimental period as compared with positive control (RA). Lut significantly suppressed TNF-α and IL-1 as compared with RA group. Histopathological examination indicated that Lut alleviated infiltration of inflammatory cells and synovial hyperplasia as well as protected joint destruction. Lut significantly suppressed inflammatory cells, and Caspase-1p10. Quercetin and Curcumin may be a potential preventive or therapeutic candidate for the treatment of inflammation and arthritis.&#x0D; Keywords: Rheumatoid arthritis, anti-arthritic activity, Quercetin, Curcumin, Freund's complete adjuvant (FCA), Leflunomide, histopathology.

Shikonin suppresses rheumatoid arthritis by inducing apoptosis and autophagy via modulation of the AMPK/mTOR/ULK-1 signaling pathway

BackgroundThe overproliferation of fibroblast-like synoviocytes (FLS) contributes to synovial hyperplasia, a pivotal pathological feature of rheumatoid arthritis (RA). Shikonin (SKN), the active compound from Lithospermum erythrorhizon, exerts anti-RA effects by diverse means. However, further research is needed to confirm SKN's in vitro and in vivo anti-proliferative functions and reveal the underlying specific molecular mechanisms. PurposeThis study revealed SKN's anti-proliferative effects by inducing both apoptosis and autophagic cell death in RA FLS and adjuvant-induced arthritis (AIA) rat synovium, with involvement of regulating the AMPK/mTOR/ULK-1 pathway. MethodsSKN's influences on RA FLS were assessed for proliferation, apoptosis, and autophagy with immunofluorescence staining (Ki67, LC3B, P62), EdU incorporation assay, staining assays of Hoechst, Annexin V-FITC/PI, and JC-1, transmission electron microscopy, mCherry-GFP-LC3B puncta assay, and western blot. In AIA rats, SKN's anti-arthritic effects were assessed, and its impacts on synovial proliferation, apoptosis, and autophagy were studied using Ki67 immunohistochemistry, TUNEL, and western blot. The involvement of AMPK/mTOR/ULK-1 pathway was examined via western blot. ResultsSKN suppressed RA FLS proliferation with reduced cell viability and decreased Ki67-positive and EdU-positive cells. SKN promoted RA FLS apoptosis, as evidenced by apoptotic nuclear fragmentation, increased Annexin V-FITC/PI-stained cells, reduced mitochondrial potential, elevated Bax/Bcl-2 ratio, and increased cleaved-caspase 3 and cleaved-PARP protein levels. SKN also enhanced RA FLS autophagy, featuring increased LC3B, reduced P62, autophagosome formation, and activated autophagic flux. Autophagy inhibition by 3-MA attenuated SKN's anti-proliferative roles, implying that SKN-induced autophagy contributes to cell death. In vivo, SKN mitigated the severity of rat AIA while also reducing Ki67 expression, inducing apoptosis, and enhancing autophagy within AIA rat synovium. Mechanistically, SKN modulated the AMPK/mTOR/ULK-1 pathway in RA FLS and AIA rat synovium, as shown by elevated P-AMPK and P-ULK-1 expression and decreased P-mTOR expression. This regulation was supported by the reversal of SKN's in vitro and in vivo effects upon co-administration with the AMPK inhibitor compound C. ConclusionSKN exerted in vitro and in vivo anti-proliferative properties by inducing apoptosis and autophagic cell death via modulating the AMPK/mTOR/ULK-1 pathway. Our study revealed novel molecular mechanisms underlying SKN's anti-RA effects.

LncRNA HOTTIP regulates TLR4 promoter methylation by recruiting H3K4 methyltransferase MLL1 to affect apoptosis and inflammatory response of fibroblast-like synoviocyte in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease, and the role of HOXA transcript at the distal tip (HOTTIP) in its pathogenesis remains underexplored. This study investigates the mechanism by which HOTTIP influences apoptosis and the inflammatory response of fibroblast-like synoviocytes (FLS). An RA mouse model was established, and clinical scores were analyzed. Pathological changes in synovial tissues, bone mineral density (BMD) of the paws, serum tartrate-resistant acid phosphatase (TRAP) activity, and TNF-α and IL-1β levels were assessed. FLS were transfected, and cell proliferation and apoptosis were examined. The RNA-pull-down assay determined HOTTIP's interaction with mixed-lineage leukemia 1 (MLL1), while RNA immunoprecipitation assay measured HOTTIP expression pulled down by MLL1. The levels of MLL1 and toll-like receptor 4 (TLR4) after MLL1 overexpression based on HOTTIP silencing were determined. Chromatin immunoprecipitation (ChIP) was performed with H3K4me3 as an antibody, followed by the evaluation of TLR4 expression. HOTTIP expression was elevated in RA mouse synovial tissues. Inhibition of HOTTIP led to reduced clinical scores, inflammatory infiltration, synovial hyperplasia, TRAP activity, and TNF-α and IL-1β levels, along with increased BMD. In vitro Interference with HOTTIP suppressed RA-FLS apoptosis and inflammation. HOTTIP upregulated TLR4 expression by recruiting MLL1 to facilitate TLR4 promoter methylation. MLL1 overexpression reversed HOTTIP silencing-mediated repression of RA-FLS apoptosis. Activation of H3K4 methylation counteracted HOTTIP knockout, ameliorating the inflammatory response. HOTTIP regulates TLR4 expression by recruiting MLL1, leading to TLR4 promoter methylation, thereby suppressing RA-FLS proliferation and inducing cell apoptosis and inflammatory response in RA.

Natural compound library screening to identify berberine as a treatment for rheumatoid arthritis.

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. 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. 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. 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.

Role of Bioactive Compounds, Novel Drug Delivery Systems, and Polyherbal Formulations in the Management of Rheumatoid Arthritis.

Rheumatoid Arthritis (RA) is an autoimmune disorder that generally causes joint synovial inflammation as well as gradual cartilage and degenerative changes, resulting in progressive immobility. Cartilage destruction induces synovial inflammation, including synovial cell hyperplasia, increased synovial fluid, and synovial pane development. This phenomenon causes articular cartilage damage and joint alkalosis. Traditional medicinal system exerts their effect through several cellular mechanisms, including inhibition of inflammatory mediators, oxidative stress suppression, cartilage degradation inhibition, increasing antioxidants and decreasing rheumatic biomarkers. The medicinal plants have yielded a variety of active constituents from various chemical categories, including alkaloids, triterpenoids, steroids, glycosides, volatile oils, flavonoids, lignans, coumarins, terpenes, sesquiterpene lactones, anthocyanins, and anthraquinones. This review sheds light on the utilization of medicinal plants in the treatment of RA. It explains various phytoconstituents present in medicinal plants and their mechanism of action against RA. It also briefs about the uses of polyherbal formulations (PHF), which are currently in the market and the toxicity associated with the use of medicinal plants and PHF, along with the limitations and research gaps in the field of PHF. This review paper is an attempt to understand various mechanistic approaches employed by several medicinal plants, their possible drug delivery systems and synergistic effects for curing RA with minimum side effects.

Knee Arthroscopy Following Total Knee Arthroplasty is Not Associated With an Elevated Risk of Infection

BackgroundRecent literature has suggested that knee arthroscopy (KA) following ipsilateral primary total knee arthroplasty (TKA) may be associated with an increased risk of periprosthetic joint infection (PJI). However, prior studies on this subject have relied on insurance databases or have lacked control groups for comparison. This study aimed to evaluate the risk of PJI in patients undergoing ipsilateral KA after primary TKA at a single institution. MethodsOur total joint registry was queried to identify 167 patients (178 knees) who underwent ipsilateral KA for any indication other than infection following primary TKA (KA + TKA group). The average time from TKA to KA was 2.1 ± 2.3 years. The average follow-up from primary TKA and from KA was 8.4 ± 5.4 years and 6.3 ± 5.4 years, respectively. The mean patient age was 63 ± 11 years, the mean body mass index was 31 ± 5, and 64% were women. The most common indications for KA were patellar clunk or patellofemoral synovial hyperplasia (66%) and arthrofibrosis (16%). Patients in the KA + TKA group were matched to 523 patients who underwent TKA without subsequent KA (TKA group) based on age, sex, date of surgery, and body mass index. The primary outcome measure was survivorship free from PJI. ResultsThere was no statistical difference in the overall rate of PJI between the KA + TKA group (n = 2, 1.1%) compared to the TKA group (n = 3, 0.6%) (hazard ratio 2.0, 95% confidence interval 0.3 to 12.0, P = .4). At 5 and 10 years after TKA, there was no difference in survivorship free of PJI between the 2 groups (P = .8 and P = .3, respectively). ConclusionsA PJI is a rare complication of KA after TKA. The rate of PJI in patients undergoing KA following TKA is not significantly increased. Level of evidenceIII.

Macrophage Activation in Synovitis and Osteoarthritis of Temporomandibular Joint and Its Relationship with the Progression of Synovitis and Bone Remodeling

This study investigates the regulatory mechanisms of synovial macrophages and their polarization in the progression of temporomandibular joint osteoarthritis (TMJOA). Macrophage depletion models were established by intra-articular injection of clodronate liposomes and unloaded liposomes. TMJOA was induced by intra-articular injection of 50 μL Complete Freund's Adjuvant and the surgery of disc perforation. The contralateral joint was used as the control group. The expression of F4/80, CD86, and CD206 in the synovium was detected by immunofluorescence staining analysis. Hematoxylin and eosin staining and TMJOA synovial score were detected to show the synovial changes in rat joints after TMJOA induction and macrophage depletion. Changes in rat cartilage after TMJOA induction and macrophage depletion were shown by safranin fast green staining. The bone-related parameters of rats' joints were evaluated by micro-computed tomography analysis. The TMJOA model induced by Complete Freund's Adjuvant injection and disc perforation aggravated synovial hyperplasia and showed a significant up-regulation of expression of F4/80-, CD86-, and CD206-positive cells. F4/80, CD86, and CD206 staining levels were significantly decreased in macrophage depletion rats, whereas the synovitis score further increased and cartilage and subchondral bone destruction was slightly aggravated. Macrophages were crucially involved in the progression of TMJOA, and macrophage depletion in TMJOA synoviocytes promoted synovitis and cartilage destruction.

Alleviated NCOA4-mediated ferritinophagy protected RA FLSs from ferroptosis in lipopolysaccharide-induced inflammation under hypoxia.

Ferroptosis is a reactive oxygen species (ROS)- and iron-dependent form of non-apoptotic cell death process. Previous studies have demonstrated that ferroptosis participates in the development of inflammatory arthritis. However, the role of ferroptosis in rheumatoid arthritis (RA) inflammatory hypoxic joints remains unclear. This study sought to explore the underlying mechanism of ferroptosis on lipopolysaccharide (LPS)-induced RA fibroblast-like synoviocytes (FLSs). FLSs, isolated from patients with RA, were treated with LPS and ferroptosis inducer (erastin and RSL-3), and ferroptosis inhibitor (Fer-1 and DFO), respectively. The cell viability was measured by CCK-8. The cell death was detected by flow cytometer. The proteins level were tested by Western blot. The cytosolic ROS and lipid peroxidation were determined using DCFH-DA and C11-BODIPY581/591 fluorescence probes, respectively. The small interfering RNA (siRNA) was used to knock down related proteins. The levels of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), iron, inflammatory cytokines (IL6 and IL8), and LDH were analyzed by commercial kits. Ferroptosis was activated by LPS in RA FLS with increased cellular damage, ROS and lipid peroxidation, intracellular Fe and IL8, which can be further amplified by ferroptosis inducer (erastin and RSL-3) and inhibited by ferroptosis inhibitor (Fer-1 and DFO). Mechanistically, LPS triggered ferroptosis via NCOA4-mediated ferritinophagy in RA FLSs, and knockdown of NCOA4 strikingly prevent the process of ferroptosis. Intriguingly, LPS-induced RA FLSs became insensitive to ferroptosis and NCOA4-mediated ferritinophagy under hypoxia compared with normoxia. Knockdown of HIF-1α reverted ferroptosis and ferritinophagy evoking by LPS-induced RA FLSs inflammation under hypoxia. In addition, low dose of auranofin (AUR) induced re-sensitization of ferroptosis and ferritinophagy through inhibiting the expression of HIF-1α under hypoxia. NCOA4-mediated ferritinophagy was a key driver of ferroptosis in inflammatory RA FLSs. The suppression of NCOA4-mediated ferritinophagy protected RA FLSs from ferroptosis in LPS-induced inflammation under hypoxia. Targeting HIF-1α/NCOA4 and ferroptosis could be an effective and valuable therapeutic strategy for synovium hyperplasia in the patients with RA.

Sinomenine ameliorates fibroblast-like synoviocytes dysfunction by promoting phosphorylation and nuclear translocation of CRMP2

Ethnopharmacological relevanceRheumatoid arthritis (RA) is a chronic autoimmune disease characterized by synovial inflammation and arthritic pain. Sinomenine (SIN), derived from the rhizome of Chinese medical herb Qing Teng (scientific name: Sinomenium acutum (Thunb.) Rehd. Et Wils), has a longstanding use in Chinese traditional medicine for treating rheumatoid arthritis. It has been shown to possess anti-inflammatory, analgesic, and immunosuppressive effects with minimal side-effects clinically. However, the mechanisms governing its effects in treatment of joint pathology, especially on fibroblast-like synoviocytes (FLSs) dysfunction, and arthritic pain remains unclear. AimThis study aimed to investigate the effect and underlying mechanism of SIN on arthritic joint inflammation and joint FLSs dysfunctions. Materials and methodsCollagen-induced arthritis (CIA) was induced in rats and the therapeutic effects of SIN on joint pathology were evaluated histopathologically. Next, we conducted a series of experiments using LPS-induced FLSs, which were divided into five groups (Naïve, LPS, SIN 10, 20, 50 μg/ml). The expression of inflammatory factors was measured by qPCR and ELISA. The invasive ability of cells was detected by modified Transwell assay and qPCR. Transwell migration and cell scratch assays were used to assess the migration ability of cells. The distribution and content of relevant proteins were observed by immunofluorescence and laser confocal microscopy, as well as Western Blot and qPCR. FLSs were transfected with plasmids (CRMP2 T514A/D) to directly modulate the post-translational modification of CRMP2 protein and downstream effects on FLSs function was monitored. ResultsSIN alleviated joint inflammation in rats with CIA, as evidenced by improvement of synovial hyperplasia, inflammatory cell infiltration and cartilage damage, as well as inhibition of pro-inflammatory cytokines release from FLSs induced by LPS. In vitro studies revealed a concentration-dependent suppression of SIN on the invasion and migration of FLSs induced by LPS. In addition, SIN downregulated the expression of cellular CRMP2 that was induced by LPS in FLSs, but increased its phosphorylation at residue T514. Moreover, regulation of pCRMP2 T514 by plasmids transfection (CRMP2 T514A/D) significantly influenced the migration and invasion of FLSs. Finally, SIN promoted nuclear translocation of pCRMP2 T514 in FLSs. ConclusionsSIN may exert its anti-inflammatory and analgesic effects by modulating CRMP2 T514 phosphorylation and its nuclear translocation of FLSs, inhibiting pro-inflammatory cytokine release, and suppressing abnormal invasion and migration. Phosphorylation of CRMP2 at the T514 site in FLSs may present a new therapeutic target for treating inflammatory joint's destruction and arthritic pain in RA.

STAT3 ACTIVATION IN THE SYNOVIAL TISSUES FROM THE HIP JOINT IN THE EARLY STAGE OF RAPIDLY DESTRUCTIVE COXOPATHY

The interleukin-6/gp130-associated Janus Kinases/STAT3 axis is known to play an important role in mediating inflammatory signals, resulting in production of matrix metalloproteinase-3 (MMP-3). The hip joints with rapidly destructive coxopathy (RDC) demonstrate rapid chondrolysis, probably by increased production of MMP-3 observed in the early stage of RDC. In the recent study, no apparent activation of STAT3 has been shown in the synovial tissues obtained from the osteoarthritic joint at operation. However, no data are currently available on STAT3 activation in the synovial tissues in the early stage of RDC. This study aimed to elucidate STAT3 activation in the synovial tissues in the early stage of RDC. Synovial tissues within 7 months from the disease onset were obtained from four RDC patients with femoral head destruction and high serum levels of MMP-3. RDC synovial tissues showed the synovial lining hyperplasia with an increase of CD68-positive macrophages and CD3-positive T lymphocytes. STAT3 phosphorylation was found in the synovial tissues by immunohistochemistry using anti-phospho-STAT3 antibody. The majority of phospho-STAT3-positive cells were the synovial lining cells and exhibited negative expression of macrophage or T cell marker. Treatment with tofacitinib, a Janus Kinase inhibitor, resulted in a decrease in phospho-STAT3-positive cells, especially with high intensity, indicating effective suppression of STAT3 activation in RDC synovial tissues. Inhibitory effect of tofacitinib could act through the Janus Kinase/STAT3 axis in the synovial tissues in the early stage of RDC. Therefore, STAT3 may be a potential therapeutic target for prevention of joint structural damage in RDC.Acknowledgements: This study was supported by Katakami Foundation for Clinical Research.