Mouse Model Of Arthritis Research Articles

Discovery of 1-(Phenylsulfonyl)-1,2,3,4-tetrahydroquinoline Derivative as Orally Bioavailable and Safe RORγt Inverse Agonists for Potential Treatment of Rheumatoid Arthritis.

The retinoic acid receptor-related orphan receptor γt (RORγt) is a key regulator of Th17 cells, associated with autoimmune diseases, making it a significant drug target. Herein, we designed and synthesized 1-(phenylsulfonyl)-1,2,3,4-tetrahydroquinoline derivatives, improving upon GSK2981278 to enhance bioavailability. Of which, D4 exhibited superior bioavailability (F = 48.1 and 32.9% in mice and rats, respectively) compared to GSK2981278 (F = 6.2 and 4.1%, respectively), and effectively treated psoriasis in mice at lower doses. Moreover, for the first time, we report the efficacies of a RORγt inverse agonist in mouse models of rheumatoid arthritis. (R)-D4, the eutomer of D4, matched or exceeded GSK2981278's therapeutic effects at lower doses, with no adverse effects observed after 2 weeks of administration. These results position (R)-D4 as a promising and orally bioavailable candidate for Th17-mediated autoimmune disease treatment.

Targeted Therapy of Antibody-Induced Autoimmune Arthritis Using Peptide-Guided Nanoparticles

Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic inflammation of the joints and it affects over 18 million people worldwide. Despite the availability of a variety of potent drugs for RA, over 30–40 percent of patients fail to achieve adequate remission, and many patients suffer from systemic adverse effects. Thus, there is an urgent need for a joint-targeted drug delivery system. Nanotechnology-based drug delivery methods offer a promising resource that is largely untapped for RA. Using the T cell-driven rat adjuvant-induced arthritis (AA) model of human RA, we developed a peptide-targeted liposomal drug delivery system for arthritis therapy. It was based on a novel joint-homing peptide ART-2 to guide liposomes entrapping dexamethasone (Dex) to arthritic joints of rats, and this approach was more effective in suppressing arthritis than the unpackaged (free) drug. To de-risk the translation of our innovative drug delivery technology to RA patients, we undertook the validation of ART-2-liposomal delivery in a genetically and mechanistically distinct arthritis model in mice, the collagen antibody-induced arthritis (CAIA) model. Using live imaging for tissue distribution of liposomes in vivo, immunohistochemistry of paws for cellular binding of ART-2, and liposomal Dex delivery, our results fully validated the key findings of the rat model, namely, preferential homing of peptide-functionalized liposomes to arthritic joints compared to healthy joints, and higher efficacy of liposomal Dex than free Dex. These results offer a proof-of-concept for the benefits of targeted drug delivery to the joints and its potential translation to RA patients.

Long-wavelength red-emitting ClO− fluorescent probe for visualizing inflammation and drug-induced renal injury

Hypochlorous acid (ClO−), a member of the reactive oxygen species (ROS) family, plays an important role in regulating physiological processes and maintaining homeostasis in the body. However, abnormal ClO− levels in the human body have been associated with a variety of pathological conditions, encompassing inflammation and kidney diseases. In this work, we have developed a novel fluorescent probe, RDNClO, specifically tailored for the sensitive detection of ClO−. RDNClO was synthesized through modifying N - (7 - (2 - carboxyphenyl) -3- (dimethylamino) - 5,6 - dihydro - 10H - benzo[c]xanthen - 10 - ylidene) - N - ethylethanaminium (RDNOH) with 1-naphthaloyl chloride moiety. Spectroscopic analyses reveal that RDNClO exhibits outstanding performance characteristics, including high selectivity, a rapid response time of <25 s, and an ultra-low detection limit of 3.7 nM. Additionally, RDNClO has demonstrated exceptional capabilities in detecting ClO− in real water samples and rapidly identifying ClO− in environmental samples, utilizing agarose as a carrier. It effectively monitors both endogenous ClO− levels in HeLa cells and exogenous ClO− levels in HEK293T cells. Furthermore, RDNClO has excelled in tracking fluctuations in ClO− levels, including in Escherichia coli, the mouse model of arthritis induced by k-carrageenan, and a mouse model of cisplatin-induced renal injury. The development of RDNClO not only establishes a robust theoretical foundation for investigating the pathogenic mechanisms of renal injury but also presents a promising tool for advancing research in this critical area.

Methotrexate inhibits glucocorticoids-induced osteoclastogenesis via activating IFN-γR/STAT1 pathway in the treatment of rheumatoid arthritis

ObjectivesRheumatoid arthritis (RA) is a chronic autoimmune disease characterised by the synovitis and bone erosion. The combination therapy of glucocorticoids (GCs) and methotrexate (MTX) is recommended in early RA management,...

Regulation of neutrophil associated RNASET2 expression in rheumatoid arthritis

Neutrophils (PMNs) are key players of innate immune responses through the release of cytoplasmic granule content and the formation of neutrophil extracellular traps (NETs). RNASET2 is an acidic ribonuclease, recently proposed as an alarmin signal associated with inflammatory responses. Here we show that, along the neutrophil maturation cascade, RNASET2 is expressed in segmented and mature PMNs. In human PMNs, RNASET2 colocalized with primary and tertiary granules and was found to be associated with NETs following PMA or Nigericin stimulation. Similarly, activation of PMNs by soluble immune complexes, a hallmark of several autoimmune diseases, also induced RNASET2-associated NETs. Genome-wide association studies recently identified RNASET2 among a cluster of genes associated with increased susceptibility to develop autoimmune diseases, including rheumatoid arthritis (RA). RNASET2 was found expressed by PMNs and macrophages infiltrating inflamed joints in a murine model of RA (K/BxN Serum-Transfer-Induced Arthritis, STIA), by immunostaining. Similar results were found in synovial biopsies of RA patients with active disease. In addition, we demonstrate that RNASET2 circulating levels correlated with the onset and the severity of disease in two mouse models of inflammatory arthritis, STIA and CIA (Collagen-Induced Arthritis) and in serum of RA patients. These results show that PMNs are an important source of RNASET2 and that its circulating levels are associated with RA development suggesting a role for RNASET2 in the pathogenesis of immune-mediated diseases.

Sinulariolide Suppresses Inflammation of Fibroblast-Like Synoviocytes in Rheumatoid Arthritis and Mitigates Collagen-Induced Arthritis Symptoms in Mice.

Rheumatoid arthritis (RA) is a systemic inflammatory disease characterized by active polyarthritis, which leads to functional loss and joint deformities. Natural compounds derived from marine organisms are considered valuable immune-modulating agents. This study aimed to assess the anti-inflammatory effect of sinulariolide, a soft coral-derived compound, on RA fibroblast-like synoviocytes and its therapeutic efficacy against collagen-induced arthritis (CIA). To determine the effects of sinulariolide on tumor necrosis factor-alpha (TNF-α)-induced inflammation, MH7A cells pre-treated with 10 ng/mL TNF-α for 24h were treated with sinulariolide. The effect of sinulariolide on proinflammatory cytokine expressions at both the mRNA and protein levels in the MH7A cells was assessed using real-time-polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). Further, we analyzed the effect of sinulariolide on the activation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways using Western blotting and the TransAM NF-κB p65 kit. To comprehensively evaluate the potential application of sinulariolide in the treatment of inflammatory diseases, we used a well-established collagen-induced arthritis (CIA) mouse model. We examined the tissue sections of the ankle joints of the mice, assessed synovial hyperplasia, inflammatory cell infiltration, and cartilage damage, and used ELISA to analyze changes in cytokine expression in the hind paw tissues. MH7A cells treated with sinulariolide showed a notable reduction in the expression of proinflammatory cytokines, which could be due to decreased activation of the MAPK and NF-kB pathways. Additionally, sinulariolide-treated mice showed significantly reduced joint swelling and lower clinical arthritis scores than those in the normal and control groups. Significant reductions in synovial hyperplasia, inflammatory cell infiltration, and cartilage damage were observed in the tissue sections of the ankle joints of the mice treated with sinulariolide. Furthermore, the expression of inflammatory cytokines in the hind paw tissue of the mice treated with sinulariolide was significantly decreased. Sinulariolide inhibited the progression of inflammation in MH7A cells. Sinulariolide treatment significantly reduced clinical arthritis symptoms and histological inflammatory responses in mice with CIA. Sinulariolide may serve as a potential therapeutic agent for RA.

The Spleen Modulates the Balance of Natural and Pathological Autoantibodies in a Mouse Model of Autoimmune Arthritis.

Natural autoantibodies (natAAbs) react with evolutionarily conserved antigens but they do not lead to pathological tissue destruction, contrary to pathological autoantibodies (pathAAbs). NatAAbs usually belong to the IgM isotype, and their network, also known as the "immunological homunculus", is thought to play a role in immunological tolerance. NatAAbs are produced by B1 cells found mostly on the serosa surfaces or the spleen. The exact relation between natAAbs and pathAAbs is still not completely understood. The recombinant human proteoglycan (PG) aggrecan G1 domain (rhG1)-induced arthritis (GIA) is an excellent mouse model for rheumatoid arthritis because it represents most of the clinical, immunological and laboratory parameters of the corresponding human pathology. Recently, we studied the role of the spleen in GIA, and found that a splenectomy modified the development of autoimmunity. To further characterize the possible role of the nAAb levels in tolerance and autoimmunity, in the present study, we set out to measure the nat- and pathAAb levels in GIA. We analyzed the natAAb levels in the serum against cartilage PG aggrecan, Hsp60 and Hsp70, and the mitochondrial citrate synthase (CS) antigens in healthy control and arthritic mice. Furthermore, we studied whether the splenectomy influenced the production of nat- and pathAAbs in mice with GIA. Our results show that the natAAb levels against PG aggrecan, Hsp60, Hsp70 and CS showed age-related variations in healthy BALB/c mice. The induction of autoimmune arthritis did not change the levels of the measured natAAbs significantly. Splenectomy, on the other hand, clearly decreased the levels of all the measured natAAbs. Interestingly, the levels of the pathAAbs showed the opposite change: they were higher in the splenectomized group than in the control arthritic mice. Based on these results, we conclude that the spleen plays a role in setting the balance between nat- and pathAAbs in autoimmune arthritis.

Low Iron Diet Improves Clinical Arthritis in the Mouse Model of Collagen-Induced Arthritis.

Background: In response to inflammation, the absorption of nutritional iron is restricted. Since the pathophysiological significance of the presence and uptake of iron in chronic inflammation is still unknown, we tested the effect of a low iron diet on the clinical course of arthritis in the mouse model of collagen-induced arthritis (CIA). Methods: Six- to eight-week-old male DBA/1 mice were fed either a normal (51 mg/kg) or a low iron diet (5 mg/kg) starting four weeks before the first immunization. From day 4 after the second collagen booster made on day 25, the development of arthritis was regularly monitored until the end of the experiment (day 34), using a standard clinical arthritis score. Concentrations of mouse anti-bovine and anti-mouse collagen type 2 IgG antibodies were measured by ELISA; blood cell counts were performed and mediators of inflammation, tissue matrix degradation, oxygenation and oxidative stress were measured in the mouse sera of both diet groups at the end of the experiment by bead-based multiplex assay. Fe2+, Fe3+, oxidized and reduced glutathione (GSH and GSSG) and malondialdehyde (MDA) were quantified in whole paw tissue by ELISA. Quantitative PCR was performed in the tissues for glutathione peroxidase 4 and other key regulator genes of iron metabolism and ferroptosis. We used nonparametric tests to compare cross-sectional data. Nonlinear regression models were used for longitudinal data of the arthritis scores. Results: Mice fed a low iron diet showed a significantly less severe course of arthritis compared to mice fed a normal iron diet (p < 0.001). The immune response against bovine and mouse type 2 collagen did not differ between the two diet groups. Mice fed a low iron diet exhibited significantly lower serum levels of tissue inhibitor of metalloproteinase-1 (TIMP-1), a central regulator of inflammation and tissue matrix degradation (p < 0.05). In addition, a low iron diet led to a significant reduction in red blood cell indices, indicating restricted iron uptake and latent iron deficiency, but had no effect on hemoglobin concentrations or red blood cell counts. There were no differences between the dietary groups in Fe2+ or Fe3+ content in the paws. Based on calculation of the GSH/GSSG ratio and high MDA levels, high oxidative stress and lipid peroxidation were likewise detected in the paws of both diet groups of mice. Consequently, no differences associated with gene expression of key regulators of iron metabolism and ferroptosis could be detected between the paws of both diet groups. Conclusions: Restricted dietary iron intake alleviates immune-mediated inflammation in CIA without causing anemia. This finding suggests a promising option for dietary treatment of arthritis in inflammation. The underlying mechanism causing reduced arthritis may be linked to the complex regulatory network of TIMP-1 and appears to be independent from the local iron levels, oxidative stress and ferroptosis in the synovial tissues.

Clinical and experimental investigations into the immune modulatory effects of Qianjinba polysaccharides on a rheumatoid arthritis mouse model: in vivo and in vitro studies

Clinical and experimental investigations into the immune modulatory effects of Qianjinba polysaccharides on a rheumatoid arthritis mouse model: in vivo and in vitro studies

Prodrug Nanomedicine for Synovium Targeted Therapy of Inflammatory Arthritis: Insights from Animal Model and Human Synovial Joint Fluid.

Many patients cannot tolerate low-dose weekly methotrexate (MTX) therapy for inflammatory arthritis treatment due to life-threatening toxicity. Although biologics offer a target-specific therapy, it raises the risk of serious infections and even cancer due to immune system suppression. We introduce an anti-inflammatory arthritis MTX ester prodrug using a long-circulating biocompatible polymeric macromolecule: folic acid (FA) functionalized hyperbranched polyglycerol (HPG). In vitro the drug MTX is incrementally released through pH and enzymatic degradation over 2 weeks. The role of matrix metalloproteinases (MMPs) in site-specific prodrug activation was verified using synovial fluid (SF) of 26 rheumatology patients and 4 healthy controls. Elevated levels of specific MMPs-markers of joint inflammation-positively correlated with enhanced prodrug release explained by acid-catalyzed hydrolysis of esters by proteases. Intravenously administered 111In-radiolabeled prodrug confirmed by SPECT/CT imaging that it accumulated preferentially in inflamed joints while reducing off-target side-effects in a mouse model of rheumatoid arthritis (RA). Added FA as a targeting vector prolonged prodrug action; prodrug with 4x less MTX applied every 2 weeks was as effective as weekly MTX therapy. The preclinical results suggest a prodrug-based strategy for the treatment of inflammatory joint diseases, with potential for other chronic inflammatory diseases and cancer.

Morinda officinalis iridoid glycosides, as an inhibitor of GSK-3β, alleviates rheumatoid arthritis through inhibition of NF-κB and JAK2/STAT3 pathway.

Morinda officinalis iridoid glycosides (MOIG) showed potential benefits in the treatment of rheumatoid arthritis (RA), but their exact mechanism has yet to be explored. To evaluate the effects of MOIG on RA, and explore the potential targets and molecular mechanism of MOIG in RA. The collagen-induced arthritis (CIA) rats were used to evaluate the effects of MOIG on RA. The proliferation, migration and invasion of fibroblast-like synoviocytes (FLSs) stimulated with or without tumor necrosis factor (TNF)-α were examined by CCK-8, wound healing and transwell assays, respectively. IF and WB were applied to investigate related mechanism in FLSs. The molecular docking, molecular dynamics simulation, CETSA and siRNA were used to analyze the interaction of MOIG with target. Finally, the adjuvant-induced arthritis (AA) mice model with gene knockdown was used to confirm the effect of MOIG on glycogen synthase kinase-3β (GSK-3β). MOIG significantly alleviated the paw swelling and synovial hyperplasia in CIA rats. Moreover, MOIG suppressed proliferation, migration and invasion, the secretion of inflammatory factors, and the expression of adhesion related proteins in TNF-α-stimulated FLSs. MOIG also inhibited the activation of Janus activating kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa-B (NF-κB) signaling pathway in FLSs. Interestingly, the plant metabolites in MOIG had a good affinity with GSK-3β, and inhibition of GSK-3β attenuated the effects of MOIG on FLSs. Knockdown GSK-3β gene could inhibit the paw swelling and inflammatory indicators, decrease the arthritis score and synovial hyperplasia, reduce the phosphorylation of p65 and STAT3 in AA mice, thereby suppressing the NF-κB and STAT3 signaling activation, and MOIG treatment had no significant effects on AA mice with si-GSK-3β. MOIG alleviates joint inflammation in RA through inhibition NF-κB and JAK2/STAT3 pathway via suppression of GSK-3β in FLSs, which provides supports for MOIG as a promising therapeutic agent of RA.

Investigation of anti-oxidant activities of pyrazole based-compounds in a mice model of rheumatoid arthritis

Investigation of anti-oxidant activities of pyrazole based-compounds in a mice model of rheumatoid arthritis

Chromone components of Saposhnikovia divaricate attenuate rheumatoid arthritis development by inhibiting the inflammatory response

Ethnopharmacological relevanceSaposhnikovia divaricata (Turcz.) Schisck., a traditional Chinese medicine (TCM), has historically been utilized in the clinical treatment of RA. It was initially documented in the 'Shennong Ben Cao Jing' as a superior quality, with the text stating: 'The herb is widely renowned for its efficacy in alleviating whole-body discomfort, bone pain, malaise, and promoting long-lasting vitality. Chromones (CHR) were identified as the primary active components in Saposhnikovia divaricata. However, the specific molecular mechanisms by which CHR impacts RA remain incompletely understood. Aim of the studyTo explore the therapeutic efficacy of CHR, a class of compound derived from Saposhnikovia divaricata, in alleviating arthropathy and immune hyperactivity in a collagen-induced arthritis (CIA) mouse model. Material and methodsSurface plasmon resonance (SPR) molecular fishing and UHPLC-QTOF/MS technology were used to identify CHR in Saposhnikovia divaricata as an active ingredient for treating RA. A CIA mouse model was used to verify the anti-RA effect of CHR in vivo. The anti-RA efficacy of CHR in vivo was evaluated by body weight change, joint swelling, arthritis index, immune organ index, ankle joint disease, and immunoglobulin G (IgG) content. The mechanism of improving RA was further analyzed by a protein chip assay and verified by Western blotting. ResultsCHR treatment reduced swelling, arthritis index, and IgG, IgG1, IgG2a, and IgG2b levels in CIA mice. Protein microarray indicated that CHR mitigated CIA-induced joint inflammation by inhibiting immune cell activation, reducing the expression of inflammatory factors and chemokines, potentially by modulating the rheumatoid arthritis pathway involving tumor necrosis factor-α (TNF-α), interleukin-17 (IL-17), and chemokines. This hypothesis was supported by the upregulation of bone morphogenetic proteins 3 (BMP3) and phospho-Smad2 (p-Smad2) proteins, coupled with the downregulation of interleukin-6 (IL-6), interleukin-1β (IL-1β), TNF-α, and IL-17A proteins in the joints of CHR-treated mice. ConclusionCHR shows promise as a potential therapeutic agent for RA, exerting its effects through anti-inflammatory mechanisms.

Study of Therapeutic Potential of Dodonaea viscosa against Rheumatoid Arthritis in Collagen Induced Arthritic Mouse Model

Abstract Rheumatoid arthritis (RA), is a complex autoimmune disease associated with high rates of mortality and extreme disability. It is characterized by gradual joint destruction and a chronic inflammatory response. As current medications are not economical and provide complications, plant-derived therapeutic practices are now being explored. Dodonaea viscosa, a flowering plant, is well-known for its antioxidant, anti-inflammatory, anti-diabetic, wound healing, and analgesic activities but no in vivo anti-arthritic study have been conducted so far. Hence, in this study, we aimed to evaluate the toxicity and therapeutic potential of Dodonaea viscosa in a collagen-induced arthritic mouse model. Chemical analysis exhibited that Dodonaea viscosa has high levels of beneficial bioactive compounds, including phenols, flavonoids, and other phytochemicals. In ex vivo and in vivo studies, Dodonaea viscosa showed significant antioxidant, anti-inflammatory, and anti-arthritic potential, while no toxic effects were found. Arthritic mice treated with Dodonaea viscosa showed reduced levels of rheumatoid factor and paw edema, while no significant effects were found on spleen indices and radiological examination of paws, compared to control untreated arthritic mice. Our study showed that treatment with Dodonaea viscosa resulted in improvements in arthritis and could therefore be a viable therapeutic source for treating patients with rheumatoid arthritis. However, further studies on humans are required for validation.

Macrophage corpses for immunoregulation and targeted drug delivery in treatment of collagen-induced arthritis mice

The role of pro-inflammatory macrophages (M1) in rheumatoid arthritis (RA) is significant, as they produce excessive cytokines. Targeting efferocytosis is a potential manner to repolarize M1 macrophages into pro-resolving M2 phenotype, which restores immune homeostasis by releasing anti-inflammatory mediators. In this study, liquid nitrogen-treated dead macrophages (DM) are employed to act as a dead cell-derived active targeted drug carrier for shikonin (SHK) and induce efferocytosis in M1 macrophages with the enhancement of SHK as an AMP-activated protein kinase (AMPK)-activator. The synergistic activation of AMPK leads to uncoupled protein 2 (UCP2) upregulation and reprograms M1 macrophages into M2 phenotypes by promoting oxidative phosphorylation. In the mouse model of collagen-induced arthritis, the intravenous administration of DM/SHK leads to a consistent transformation of M1 macrophages into the M2 phenotype within the infiltrative synovium. This transformation of macrophages results in the restoration of immune homeostasis in the synovium through an increase in the production of pro-resolving mediators. Additionally, it inhibits synovial proliferation and infiltration and provides protection against erosion of cartilage and bone. In summary, LNT-based DM serves as an active targeting drug carrier to M1 macrophages and also acts synergistically with SHK to target immunometabolism.

A Novel Etanercept-loaded Nano-emulsion for Targeted Treatment of Inflammatory Arthritis via Draining Lymph Node.

Rheumatoid arthritis (RA) is a systemic autoimmune disease (AD), and the global incidence rate is 0.5 ~ 1%. Existing medications might reduce symptoms, however, there is no known cure for this illness. Etanercept (EN) can competitively inhibit TNF-α binding to the TNF receptor on the cell surface to treat RA. However, subcutaneous injection of free EN predisposes to systemic distribution and induces immune system hypofunction. Draining lymph nodes (LNs) play a significant role in the onset, maintenance, and progression of RA as they are the primary sites of aberrant immune response and inflammatory cytokine production. The purpose of this study was to successfully treat RA with etanercept by encapsulating it in nanoemulsions (NEs/EN) and then delivering it specifically to draining LNs. The EN-loaded NEs were prepared by high-pressure homogenization method and modified with DSPE-mPEG2000 and Ca(OH)2. A novel nano-emulsion (NE) was constructed to deliver EN (NE/EN) to RA-draining LNs. To decrease aggregation and load EN, DSPE-mPEG2000 and Ca(OH)2 were successively decorated on the surface of the lipid injectable emulsions. The hydrodynamic diameter and morphology of NEs/EN were investigated by using a laser particle size analyzer and transmission electron microscopy, respectively. The in vivo fluorescence imaging system was used to study the in vivo LN targeting ability of the formulation. In the therapeutic experiment, NEs/EN was subcutaneously administrated to inhibit the development of the mouse arthritis model. Circular dichroism spectrum and L929 cell experiment confirmed that NEs encapsulation had no impact on the biological activity of EN. In vivo investigation on collagen-induced arthritis (CIA) mouse model showed that NEs/EN have good inguinal lymph node targeting capabilities, as well as, anti-inflammatory effect against RA. Compared with the free group, the paw thickness and arthritic score in NEs/EN group were significantly alleviated. Moreover, the concentration of pro-inflammatory cytokines TNF-α and IL-1β in NEs/EN-treated mice was lower than that in free EN. NEs/EN effectively improve the effectiveness of EN in the treatment of RA. Our work provides an experimental foundation for expanding the clinical application of EN.

Locally Injectable Chitosan/β-Glycerophosphate Hydrogel Doped with Triptolide-Human Serum Albumin Nanoparticles for Treating Rheumatoid Arthritis.

Rheumatoid arthritis (RA) tends to occur in symmetrical joints and is always accompanied by synovial hyperplasia and cartilage damage. Triptolide (TP), an extract from Tripterygium, has anti-inflammatory and immunomodulatory properties and could be used in the treatment of RA. However, its poor water solubility and the multi-system lesions caused by the use of this substance limit its clinical application. Therefore, it would be of great significance to assemble a composite nanoparticle hydrogel and apply it to a collagen-induced arthritis (CIA) mouse model to investigate the therapeutic effect and biosafety of this compound. TP@HSA nanoparticles (TP@HSA NPs) were fabricated with a self-assembly method; a thermosensitive hydrogel loaded with the TP@HSA NPs (TP@HSA NP hydrogel) was prepared by using chitosan and beta- glycerophosphate (β-GP) and was then intra-articularly injected into CIA mice. The changes in joint swelling were measured with a digital caliper, and inflammation and cartilage damage were evaluated by using hematoxylin and eosin (H&E) and safranin O-fast green (SO&FG) staining, respectively. TP@HSA NPs with an average diameter of 112 ± 2 nm were successfully assembled, and their encapsulation efficiency and drug loading efficiency were 47.6 ± 1.5% and 10.6 ± 3.3%, respectively. The TP@HSA NP hydrogel had a gelation temperature of 30.5 ± 0.2 °C, which allows for its injection at low temperatures and its sol-gel transformation under physiological conditions within 2 min, making it a suitable drug depot. The TP@HSA NP hydrogel was intra-articularly injected into CIA mice; it released TP locally and exerted anti-inflammatory and immunomodulatory effects, alleviating synovial inflammation and cartilage damage effectively. We successfully fabricated a TP@HSA NP-loaded thermosensitive hydrogel with good biosafety, which can release TP slowly for the treatment of RA. Our study provides a basis for the development of TP-based innovative preparations and has good application prospects.

Low dose methotrexate impaired T cell transmigration through down-regulating CXCR4 expression in rheumatoid arthritis (RA)

BackgroundCXC chemokine CXCL12 is involved in the pathological development of rheumatoid arthritis (RA) through abnormal migration of peripheral immune cells in the joint. Although low dose methotrexate (MTX) is clinically used to treat RA patients, CXCL12 signaling responses to MTX-mediated treatments is still not well understood.MethodsIn this study, we examined the expression of CXCR4 (cognatic receptor for CXCL12) in peripheral T cells from RA patients and arthritis mice models received from low dose MTX therapies. The effects of low dose MTX on CXCR4 were further determined via both in vitro CD3+ T cells and Cxcr4 conditional knockout (CKO) arthritis mice models.ResultsOur clinical data shows that low dose MTX treatment was clinically associated with down-regulated expression of chemokine receptor CXCR4 on patient peripheral T cells. In vitro, low dose MTX significantly decreased cell transmigration through down-regulated CXCR4’s expression in CD3+ T cells. Consistently, CD3+ T cells treated with low dose MTX demonstrated an increased genomic hypermethylation across the promoter region of Cxcr4 gene. Furthermore, our preclinical studies showed that low dose MTX-mediated downregulation of CXCR4 significantly improved the pathological development in mouse arthritis models. Conditional disruption of the Cxcr4 gene in peripheral immune cells potentially alleviated inflammation of joints and lung tissue in the arthritis mice, though genetic modification itself overall did not change their clinical scores of arthritis, except for a significant improvement on day 45 in CXCR4 CKO arthritis mice models during the recovery phase.ConclusionOur findings suggest that the effect of low dose MTX treatment could serve to eliminate inflammation in RA patients through impairment of immune cell transmigration mediated by CXCR4.

LncRNA MIAT suppresses inflammation in LPS-induced J774A.1 macrophages by promoting autophagy through miR-30a-5p/SOCS1 axi

Accumulated data implicate that long noncoding RNA (lncRNA) plays a pivotal role in rheumatoid arthritis (RA), potentially serving as a competitive endogenous RNA (ceRNA) for microRNAs (miRNAs). The lncRNA myocardial infarction-associated transcript (MIAT) has been demonstrated to regulate inflammation. However, the role of MIAT in the inflammation of RA remains inadequately explored. This study aims to elucidate MIAT’s role in the inflammation of lipopolysaccharide (LPS)-induced macrophages and to uncover the underlying molecular mechanisms. We observed heightened MIAT expression in LPS-induced J774A.1 cells and collagen-induced arthritis mouse models, in contrast to the expression pattern of miR-30a-5p. Silencing MIAT resulted in increased expression of the inflammatory cytokines IL-1β and TNF-α. Simultaneously, MIAT interference significantly impeded macrophage autophagy, evidenced by decreased expression of autophagy-related markers LC3-II and Beclin-1, alongside increased levels of p62 in LPS-induced J774A.1 cells. Notably, MIAT functioned as a ceRNA, sponging miR-30a-5p and exerting a negative regulatory influence on its expression. SOCS1 emerged as a target of miR-30a-5p, modulated by MIAT. Mechanistically, inhibiting miR-30a-5p reversed the impact of MIAT deficiency in promoting LPS-induced inflammation, while SOCS1 knockdown countered the cytokine inhibitory effect induced by silencing miR-30a-5p. In summary, this study indicates that lncRNA MIAT suppresses inflammation in LPS-induced J774A.1 macrophages by stimulating autophagy through the miR-30a-5p/SOCS1 axis. This suggests that MIAT holds promise as a potential therapeutic target for RA inflammation.

Acupuncture at the Zusanli acupoint can reduce the inflammatory response in AIA mice by regulating the arachidonic acid and pentose phosphate pathways

BackgroundRheumatoid arthritis (RA) is an autoimmune disease characterized by synovitis, which can lead to joint deformity. Acupuncture treatment stimulates specific acupoints to adjust qi and blood function, relieving joint inflammation and pain. MethodsUltra-high performance liquid chromatography-mass spectrometry (UPLC-QTOF-MS) was utilized for non-targeted metabolomics analysis of plasma samples from the blank group, Adjuvant-Induced Arthritis (AIA) model mice model mice group, and acupuncture group. Metabolite hierarchical clustering analysis, multivariate statistical analysis, standardized processing, principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and other methods were employed to identify targeted metabolites affected by acupuncture treatment in AIA mice. The related metabolic pathways were analyzed using KEGG pathway. ResultsHistopathological results demonstrated that acupuncture at Zusanli point (ST 36) significantly improved the inflammatory response in AIA mice. The PCA score plot indicated relatively close sample clustering within each group with significant differences observed between the four groups, confirming successful establishment of the AIA animal model with metabolic disorders occurring. Acupuncture treatment effectively corrected these metabolic disorders. Plasma metabolomics identified a total of 10 differential metabolites primarily associated with arachidonic acid and pentose phosphate metabolic pathways. ConclusionsAcupuncture at ST36 can significantly improve the inflammatory response in AIA mice through modulation of arachidonic acid and pentose phosphate metabolic pathways.