Clinical Arthritis Score Research Articles

Evaluation of Antiarthritic Protective Effect of Erlangea tomentosa (Oliv. & Hiern) S. Moore (Asteraceae) Methanol Leaf Extract in Complete Freund’s Adjuvant-Induced Arthritis in Rats

Objective: Given the rising interest in plant-based therapies for chronic inflammatory diseases like arthritis, this study aimed to explore the potential of Erlangea tomentosa, a plant known for its medicinal properties, as an anti-arthritic agent Methodology: The plant extract was administered to arthritic rats that had been injected with the Complete Freund’s adjuvant (CFA). The physical anti-arthritis effects of the plant were evaluated using body weight, paw diameter, and a clinical scoring approach. The systemic anti-arthritis properties were evaluated using hematological and biochemical markers of arthritis at the conclusion of the study. Paw joints were taken out for histopathological investigation, and the body weight organ indices for gross abnormalities. Results: It was found that the methanol leaf extract of the plant significantly reduced the arthritis state, which was obvious in clinical arthritis scoring, CFA-injected paw size, body weight, and the preservation of hematological and biochemical indicators. Histopathology and organ indices also confirmed that the plant extract could reduce the pain and inflammation of animals with CFA-induced arthritis. Conclusion: The authors have concluded that the plant might help with arthritis. Research into a specific proinflammatory mediator, such as interleukins and tumor necrosis factor, would confirm this activity.

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.

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.

Complement factor H-related protein 5 alleviates joint inflammation and osteoclast differentiation by disrupting RANK-JNK signaling in collagen antibody-induced arthritis mouse model

BackgroundComplement Factor H-Related protein 5 (CFHR5) belongs to the factor H/CFHR family and regulates the complement system by modulating factor H’s inhibitory activity against C3b. Despite its known role, the impact of CFHR5 on autoimmune arthritis and its relationship to pathophysiological changes in arthritis and bone loss remain unclear. This study aimed to assess the effect of CFHR5 on aggressive osteoclast activity and arthritis using a murine model of collagen antibody-induced arthritis (CAIA). MethodsThe effect of recombinant CFHR5 protein (rCFHR5) on arthritis were evaluated in CAIA. The mice were divided into three group and intraperitoneally treated with rCFHR5, methotrexate (MTX) as positive control or PBS as negative control. In the CAIA mouse model, the rCFHR5-treated group significantly reduced the incidence and clinical arthritis equivalent to the MTX group. Clinical arthritis scores, incidence and body weight were measured, and histological analysis of ankle joints was performed by Hematoxylin and Eosin (H&E) and Safranin O − Fast green (SOFG), Tartrate-resistant acid phosphatase (TRAP) staining and Immunohistochemistry. Moreover, to investigate the rCFHR5 role, we isolated murine osteoclast precursor cells (OCPs) from each group, induced osteoclasts with M−CSF and RANKL, and performed TRAP and F-actin staining. To verify the mechanism, mRNA and protein analyses were performed in OCPs. ResultsHistological examination of ankle joints revealed substantial reductions in synovial hyperplasia, bone marrow inflammation, bone erosion, cartilage destruction and TRAP-positive cells in the rCFHR5 group compared to the vehicle group. The ankle joints of the rCFHR5 group showed markedly decreased expression of proinflammatory cytokines (TNF-α, IL-1β and IL-6). Mechanically, treatment with rCFHR5 inhibited RANKL-mediated osteoclast differentiation from OCPs and disrupted the RANK-JNK signaling. These findings demonstrate that treatment with rCFHR5 attenuates joint inflammation and reduces osteoclast differentiation, indicating its potential anti-inflammatory effect in autoimmune arthritis models.

Wutou decoction attenuates rheumatoid arthritis in rats through SIRT1-mediated deacetylation of the HMGB1/NF-κB pathway

Ethnopharmacological relevanceIn traditional Chinese medicine (TCM), Wutou Decoction (WTD) has long been used to alleviate arthritis. Emerging studies have reported that WTD could improve the symptoms of rheumatoid arthritis (RA). However, the mechanism by which WTD is involved in the treatment of RA remains elusive, posing a challenge to the worldwide acceptance of WTD as an efficient RA therapy. Aim of the studyThis study investigated the antiarthritic efficacy of WTD in a collagen-induced arthritis (CIA) rat model and explored silent information regulator 1 (SIRT1)-mediated deacetylation of the high mobility group box 1 (HMGB1)/NF-κB pathway. Materials and methodsA rat CIA model was used to evaluate the antiarthritic activity of WTD. Clinical arthritis score assessment, left ankle thickness assessment, micro-CT, histopathological staining, immunofluorescence staining, and ELISA were conducted to elucidate the anti-inflammatory effects of WTD. The M1 macrophage polarization state, cell viability, and invasion were also determined to assess the effects of WTD on macrophage proliferation and invasion in vitro. Additionally, in vivo and in vitro HMGB1 nuclear translocation and NF-κB activation were analysed. Finally, deacetylase activity was assessed by Western blot, NAD+/NADH analysis, and co-immunoprecipitaion. ResultsWTD significantly alleviated arthritis in CIA rats and inhibited pathological changes in joint lesions while concurrently suppressing TNF-α, IL-6, and IL-1β release. Mechanistically, WTD suppressed M1 infiltration in ankle tissues and their invasion in vitro. Furthermore, WTD downregulated HMGB1/p65 nuclear translocation and acetylation, which may be associated with SIRT1 upregulation. ConclusionsOverall, WTD potentially alleviates RA through SIRT1-mediated downregulation of HMGB1 and NF-κB acetylation.

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.

Swimming exercise alleviates pathological bone features in curdlan-injected SKG mice by inducing irisin expression

This study assessed the therapeutic potential of swimming exercise in the curdlan-injected SKG mouse model and investigated the modulatory effects of irisin on inflammation. Curdlan-injected SKG were randomly assigned to either a home-cage group or a swimming group for 6 weeks. Changes in clinical arthritis scores and ankle thickness were measured weekly. Post-swimming program, mice were anesthetized for collection of vastus lateralis muscle and blood, which was followed by histological analysis, micro-CT imaging of the ankle joints, and the measurement of pro-inflammatory cytokines and irisin levels. Additionally, curdlan-injected SKG mice were intravenously injected with recombinant irisin protein and observed. Finally, serum levels of irisin in healthy control and ankylosing spondylitis (AS) patient groups were measured by ELISA. The swimming group of curdlan-injected SKG mice exhibited significant improvements in arthritis and enthesitis compared to the home-cage group. In particular, micro-CT and histological analyses revealed a notable reduction in pathological bone features in the swimming group compared to the home-cage group. Muscle endurance was also enhanced in the swimming group compared to the home-cage group, as determined by the wire-hanging test. Intriguingly, irisin levels not only were statistically increased in the swimming group but, also, TNF-α, IL-1β, and IL-6 levels were decreased. Additionally, injection of irisin protein slightly attenuated both arthritis and enthesitis in curdlan-injected SKG mice. Meanwhile, irisin serum levels were declined in AS patients. Overall, we found that swimming exercise attenuated pathological bone features in an AS animal model, potentially mediated by increased irisin serum levels with associated anti-inflammatory effects.

LC-MS-based rheumatoid arthritis serum metabolomics reveals the role of deoxyinosine in attenuating collagen-induced arthritis in mice

Rheumatoid arthritis (RA) is a persistent autoimmune condition with no identified cure currently. Recently, scientists have applied metabolomics to investigate altered metabolic profiles and unique diseases-associated metabolic signatures. Herein, we applied metabolomics approach to analyze serum samples of 41 RA patients and 42 healthy controls (HC) with the aim to characterize RA patients' metabolic profile, investigate related underlying pathological processes, and identify target metabolites. By utilizing ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry, we found 168 proposed metabolites and 45 vital metabolic pathways. Our analysis revealed that deoxyinosine (DI), a metabolite of the purine metabolic pathway, was the most significant reduced metabolite in RA patients. Furthermore, through targeted detection, we confirmed lower concentration of DI in RA patients' peripheral blood. Moreover, DI inhibited lipopolysaccharide-induced inflammation both in vitro and in vivo. We further assessed DI's therapeutic potential in a collagen-induced arthritis (CIA) murine model. The results revealed that DI attenuated CIA, as evidenced by significantly lowered clinical scores of arthritis, alleviated joint swelling, and mitigated bone destruction. Moreover, we elucidated the underlying mechanism by which DI increased the population of myeloid-derived suppressor cells (MDSCs) and suppressed the proliferation of induced T cells. Collectively, these findings suggested that DI potentially ameliorated RA by inducing immunosuppressive MDSCs. The study provides key observations on RA pathogenesis and may contribute to developing novel therapeutic strategies for this debilitating condition.

Effect and mechanism of aqueous extract of Strychni Semen on bone destruction in rats with type Ⅱ collagen-induced rheumatoid arthritis

To investigate the mechanism of action of aqueous extract of Strychni Semen(SA) on bone destruction in rats with type Ⅱ collagen-induced arthritis(CIA), the SD rats were randomly divided into normal group, model group, low, medium, and high dose(2.85, 5.70, and 11.40 mg·kg~(-1)) groups of SA, and methotrexate group. Except for the normal group, the CIA model was prepared for the other groups. After the second immunization, different doses of SA were given to the low, medium, and high dose groups of SA once a day, and the methotrexate group was given once every three days. 0.3% sodium hydroxymethylcellulose(CMC-Na) was given once a day to the normal and model groups for 28 d. The clinical score of arthritis was evaluated every three days. Micro computed tomography(Micro-CT) method was used to evaluate the degree of bone destruction. Histopathological changes in the joint tissue and the number of osteoclasts in CIA rats were evaluated by hematoxylin-eosin(HE) staining and tartrate-resistant acid phosphatase(TRAP) staining. The expression of interleukin-1β(IL-1β) in the joint tissue of rats was detected by immunohistochemistry. Western blot was used to detect key protein expression in mitogen-activated protein kinase(MAPK) and phosphatidylinositol 3-kinase/protein kinase B(PI3K/Akt) signaling pathways in the joint tissue of rats. The results showed that different doses of SA were able to improve the red and swollen inflammatory joint and joint deformity in CIA rats to varying degrees, reduce the clinical score, inhibit synovial inflammation, vascular opacification, cartilage erosion, and bone destruction, and reduce the number of TRAP-positive cells in bone tissue. Micro-CT results showed that the SA was able to increase bone mineral density, bone volume fraction, trabecular reduce, and trabecular number and reduce bone surface/bone volume and trabecular separation/spacing. Different doses of SA could down-regulate the protein expression of IL-1β, p-JNK, p-ERK, p-p38, PI3K, and p-Akt to varying degrees. In conclusion, SA can improve disease severity, attenuate histopathological and imaging changes in joints, and have osteoprotective effects in CIA rats, and its mechanism of action may be related to the inhibition of the overactivation of MAPK and PI3K/Akt signaling pathways.

The complement factor H-related protein-5 (CFHR5) exacerbates pathological bone formation in ankylosing spondylitis.

Ankylosing spondylitis (AS) is a chronic inflammatory disease, characterized by excessive new bone formation. We previously reported that the complement factor H-related protein-5 (CFHR5), a member of the human factor H protein family, is significantly elevated in patients with AS compared to other rheumatic diseases. However, the pathophysiological mechanism underlying new bone formation by CFHR5 is not fully understood. In this study, we revealed that CFHR5 and proinflammatory cytokines (TNF, IL-6, IL-17A, and IL-23) were elevated in the AS group compared to the HC group. Correlation analysis revealed that CFHR5 levels were not significantly associated with proinflammatory cytokines, while CFHR5 levels in AS were only positively correlated with the high CRP group. Notably, treatment with soluble CFHR5 has no effect on clinical arthritis scores and thickness at hind paw in curdlan-injected SKG, but significantly increased the ectopic bone formation at the calcaneus and tibia bones of the ankle as revealed by micro-CT image and quantification. Basal CFHR5 expression was upregulated in AS-osteoprogenitors compared to control cells. Also, treatment with CFHR5 remarkedly induced bone mineralization status of AS-osteoprogenitors during osteogenic differentiation accompanied by MMP13 expression. We provide the first evidence demonstrating that CFHR5 can exacerbate the pathological bone formation of AS. Therapeutic modulation of CFHR5 could be promising for future treatment of AS. KEY MESSAGES: Serum level of CFHR5 is elevated and positively correlated with high CRP group of AS patients. Recombinant CFHR5 protein contributes to pathological bone formation in in vivo model of AS. CFHR5 is highly expressed in AS-osteoprogenitors compared to disease control. Recombinant CFHR5 protein increased bone mineralization accompanied by MMP13 in vitro model of AS.

Norisoboldine Reduces Arthritis Severity by Attenuating Inflammation, Oxidative Stress, and Extracellular Matrix Degradation in a Rat Model of Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune disorder marked by persistent joint inflammation, pain, and tissue degradation. This study evaluates the therapeutic potential of Norisoboldine (NOR), an isoquinoline alkaloid from Lindera aggregata, in a rat model of RA. Rats were divided into five groups: normal control (G1), RA model (G2), NOR-treated groups at 15 mg/kg (G3) and 30 mg/kg (G4), and methotrexate-treated group (G5). NOR's anti-arthritic effects were assessed by measuring clinical arthritis scores and inflammatory markers (RF, CRP, TNF-α, IL-6, IL-10). Oxidative stress markers (MDA, SOD, catalase, GPx) and pathways (NF-κB/IKKβ and Nrf2/Keap1) were also evaluated. Histopathology assessed synovial inflammation and tissue degradation. NOR treatment significantly reduced arthritis severity, as evidenced by decreased clinical arthritis scores and inflammatory markers in RA rats. NOR also exhibited strong antioxidant effects, demonstrated by decreased MDA levels and enhanced SOD, catalase, and GPx activities. NOR further downregulated matrix metalloproteinases (Mmp-2, Mmp-3), aggrecanases (Adamts-4, Adamts-5), and PCNA expression. Histopathology confirmed marked reductions in synovial inflammation and tissue damage in NOR-treated groups. These findings suggest that NOR's anti-inflammatory and antioxidant properties contribute to reducing both inflammation and the overall severity of RA. NOR's multifaceted actions support its potential as a novel therapeutic agent for RA. NOR demonstrates protective effects in RA rats by reducing inflammation, oxidative stress, and extracellular matrix degradation, offering promise as a therapeutic option to manage RA pathology comprehensively.

Nesting behavior is associated with body weight and grip strength loss in mice suffering from experimental arthritis

Objective animal health evaluation is essential to determine welfare and discomfort in preclinical in vivo research. Body condition scores, body weight, and grimace scales are commonly used to evaluate well-being in murine rheumatoid arthritis (RA) and osteoarthritis experiments. However, nest-building, a natural behavior in mice, has not yet been evaluated in wild type (WT) or genetically modified rodents suffering from collagen antibody-induced arthritis (CAIA). To address this, we analyzed nesting behavior in WT mice, calcitonin gene-related peptide alpha-deficient (αCGRP-/-) mice, and calcitonin receptor-deficient (Calcr-/-) mice suffering from experimental RA compared to healthy control (CTRL) groups of the same genotypes. CAIA was induced in 10–12-week-old male mice, and clinical parameters (body weight, grip strength, clinical arthritis score, ankle size) as well as nesting behavior were assessed over 10 or 48 days. A slight positive association between the nest score and body weight and grip strength was found for animals suffering from CAIA. For the clinical arthritis score and ankle size, no significant associations were observed. Mixed model analyses confirmed these associations. This study demonstrates that clinical effects of RA, such as loss of body weight and grip strength, might negatively affect nesting behavior in mice. Assessing nesting behavior in mice with arthritis could be an additional, non-invasive and thus valuable health parameter in future experiments to monitor welfare and discomfort in mice. During severe disease stages, pre-formed nest-building material may be provided to animals suffering from arthritis.

Administration of Recombinant TAPBPL Protein Ameliorates Collagen-Induced Arthritis in Mice.

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease distinguished by synovial hyperplasia and a progressive destruction of joints. T cells are critical players in the pathogenesis of RA. We have previously identified a novel immune checkpoint molecule, TAPBPL, that inhibits T cell functions in vitro. As a model for human RA, we investigated the ability of the TAPBPL protein to ameliorate collagen type II (CII)-induced arthritis (CIA) in mice that were injected with recombinant TAPBPL or a control protein. The mice were analyzed for CIA development, immune cells, and their responses. We found that TAPBPL protein significantly decreased CIA incidence and reduced clinical and pathological arthritis scores, which were related to a lower number of activated CD4 T cells but a greater number of regulatory T cells (Tregs) in the spleen, and a reduction of Th1/Th17 inflammatory cytokines in the joints and serum. Importantly, TAPBPL protein inhibited CII-specific T cell growth and Th1 and Th17 cytokine expression and reduced the production of CII autoantibodies in the serum. Our results suggest that TAPBPL protein can ameliorate CIA in mice and has the potential to be used in the treatment of patients with RA.

Ganoderma lucidum polysaccharide peptide (GLPP) attenuates rheumatic arthritis in rats through inactivating NF-κB and MAPK signaling pathways

BackgroundNot many drugs with fewer side effects are available for the treatment of rheumatoid arthritis (RA). Ganoderma lucidum polysaccharide peptide (GLPP) has good immunomodulatory effects, but whether it is effective in managing RA is not clear. PurposeThis study was conducted to examine the anti-RA activity and possible mechanisms of GLPP in collagen-induced arthritis (CIA) rats. MethodsMale Wistar rats were intradermally injected with bovine type II collagen in the tail base to establish the CIA model and were orally administered 100 or 200 mg/kg GLPP for 35 days. Paw thickness, clinical arthritis scores, gait analysis, organ index determination, blood cell counts, micro-CT imaging and pathological staining were performed on the rats. Liver and kidney function were measured by commercial kits, and antibody levels were measured by ELISA kits. RA-related protein levels were detected by Western blotting. ResultsGLPP effectively alleviated CIA symptoms and reduced immune organ indexes, antibody levels and systemic organ injury. GLPP decreased the protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, matrix metalloproteinase (MMP)2, MMP9, MMP13, BCL-2, OPN, β-Catenin, and hypoxia inducible factor (HIF)-1α and increased the protein expression of BAX in the joint tissues of CIA rats. Moreover, GLPP decreased the phosphorylation levels of p65, IκB-α and ERK1/2. ConclusionGLPP effectively alleviated RA symptoms in CIA rats by inhibiting the NF-κB and MAPK pathways. This study suggests a promising therapeutic effect of mushroom-derived polysaccharide peptides on RA.

Dopamine D2 receptor on CD4+ T cells is protective against inflammatory responses and signs in a mouse model of rheumatoid arthritis

BackgroundDopamine is a neurotransmitter and has been found to regulate lymphocytes by acting on dopamine receptors (DRs). CD4+ T cells express all the five subtypes of DRs, D1R to D5R. Although CD4+ T cells have been involved in pathogenesis of rheumatoid arthritis (RA), roles of DRs expressed on these cells in RA are poorly understood. This study determined whether D2R expressed on CD4+ T cells regulates inflammatory responses and signs in collagen type II (CII)-induced arthritis (CIA), a mouse model of RA.MethodsDBA/1 mice and C57BL/6 mice with global D1r or D2r deficiency (D1r–/– or D2r–/–) or CD4+ T cell-specific D2r deletion (D2rfl/fl/CD4Cre) were used to prepare CIA model by intradermal injection of CII. D2R agonist sumanirole was intraperitoneally administered in CIA mice. CD4+ T cells obtained from CIA mice were exposed to sumanirole or/and D2R antagonist L-741,626 in vitro. Arthritic symptoms were assessed by clinical arthritis scores. Flow cytometric assay measured frequencies of CD4+ T cell subsets (Th1, Th2, Th17 and Treg cells). Expression of specific transcription factors for the CD4+ T cell subsets was tested by Western blot. Cytokine production was estimated by quantitative PCR and ELISA.ResultsCIA mice manifested a bias of CD4+ T cells towards Th1 and Th17 cells. D2r–/– CIA mice showed a stronger bias towards Th1 and Th17 phenotypes than CIA mice, while D1r–/– CIA mice did not show the changes. CD4+ T cell-specific D2r deletion exacerbated both the polarization towards Th1 and Th17 cells and the symptoms of arthritis. Sumanirole administration in CIA mice ameliorated the bias of CD4+ T cells towards Th1 and Th17 phenotypes as well as arthritic symptoms. Sumanirole treatment of in vitro CD4+ T cells obtained from CIA mice promoted the shift to Treg cells, and the effect of sumanirole was blocked by L-741,626.ConclusionsD2R expressed on CD4+ T cells is protective against imbalance between pro-inflammatory and anti-inflammatory T cells and arthritic symptoms in CIA.

Associations between power Doppler ultrasound findings and B-mode synovitis and clinical arthritis in juvenile idiopathic arthritis using a standardised scanning approach and scoring system

ObjectivesTo describe power Doppler (PD) ultrasound findings in joint regions with B-mode (BM) synovitis using a standardised scanning protocol and scoring system in patients with juvenile idiopathic arthritis (JIA). Further,...

Gallic acid regulates immune response in a mouse model of rheumatoid arthritis.

Previous studies revealed that gallic acid (GA) exerts anti-inflammation and immuno-regulatory properties. This study aims to explore the pharmacological activities of GA in collagen-induced arthritis (CIA) mouse model. Male DBA/1J mice were used to construct the CIA model. The mice were administrated with GA for 3 weeks. Clinical arthritis scores and hind paw volume were evaluated over the experimental period. qPCR and Western blot analysis were used to determine the levels of matrix metallopeptidases (MMPs) and cytokines. In addition, flow cytometry was used to measure the populations of Th17 and Treg cells. ELISAs were used to determine the cytokines in the serum and ankle joint tissues. Treatment of GA (40 and 80 mg/kg/d) reduced clinical arthritis scores and hind paw volume in the CIA mouse model. Besides, treatment of GA reduced the overexpression of MMPs and modulated the dysregulation of inflammation-related cytokines. Flow cytometry showed that treatment of GA decreased the population of Th17 cells, and increased the population of Treg cells, as supported by treatment of GA regulated the Th17/Treg-related cytokines. GA attenuates symptoms in the CIA mouse model by anti-inflammation and regulating Th17/Treg cell imbalance.

Ca-DEX biomineralization-inducing nuts reverse oxidative stress and bone loss in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a common autoimmune disease, and the inflammatory response during its development can lead to joint cartilage and bone damage up to disability. Dexamethasone (DEX) can effectively alleviate the inflammatory response in RA, but the severe adverse effects that occur after its long-term administration limit its clinical development. Herein, we propose a Ca-DEX biomineralization-inducing nut (CaCO3-DEX) with controlled release properties for mitigating the toxic side effects of DEX in RA treatment, especially the damage to cartilage and bone. CaCO3-DEX releases the drug and Ca2+ preferentially in an inflammatory environment. Both in vitro and in vivo studies demonstrate that CaCO3-DEX significantly reduces the secretion of pro-inflammatory factors and inhibits ROS production in vitro, as well as demonstrates superior pro-biomineralization and osteogenic differentiation potential. In the collagen-induced rheumatoid arthritis model (CIA model), CaCO3-DEX significantly reduces the clinical score of arthritis in mice, and the imaging results show a noticeable relief of edema and bone erosion in CIA model mice treated with CaCO3-DEX, while inflammatory factors at the injury areas are significantly reduced, which provides favorable protection to cartilage and bone.

Loss of AKAP12 aggravates rheumatoid arthritis-like symptoms and cardiac damage in collagen-induced arthritis mice.

A-kinase anchoring protein 12 (AKAP12) has been identified as an anti-inflammatory and anti-fibrotic regulator in chronic inflammation and cardiovascular disease. However, the potential of AKAP12 in autoimmune disorders, rheumatoid arthritis (RA) and associated cardiac complications remains elusive. Here, a murine model of collagen-induced arthritis (CIA) was successfully induced, followed by adenovirus-mediated AKAP12 short hairpin RNA (shRNA) treatment. AKAP12 silenced mice displayed elevated clinical arthritis scores and significant ankle joint swelling. AKAP12 loss in CIA mice increased inflammatory cell infiltration and cartilage erosion, increased the levels of anti-IIC IgG and inflammatory cytokines IL-1β, IL-6, tumor necrosis factor (TNF)-α in serum, and upregulated the expression of cartilage-degrading enzymes MMP-1, MMP-3, MMP-13 in synovium, but reduced IL-10. The number of M1 macrophages and the expression of the markers (CCR7, IL-6, TNF-α and iNOS) was enhanced in synovial tissues, while M2 polarized macrophages and the makers (IL-10 and arginase-1) were reduced in response to AKAP12 loss. Moreover, low expression of AKAP12 was detected in the hearts of CIA mice. Loss of AKAP12 results in increased cardiac inflammation and fibrosis. This work suggests that AKAP12 loss aggravates joint inflammation likely through the promotion of M1 macrophage polarization and exacerbates inflammation-caused cardiac fibrosis.

GCSB-5 regulates inflammatory arthritis and pain by modulating the mitogen-activated protein kinase signaling pathway in a murine model of rheumatoid arthritis.

This study aimed to determine whether GCSB-5 has anti-inflammatory and antinociceptive effects in mice with collagen-induced arthritis (CIA), an animal model of rheumatoid arthritis (RA), and investigate the influence of GCSB-5 on the mitogen-activated protein kinase (MAPK) pathway. The experimental animal study was designed to include five groups: CIA mice treated with GCSB-5 (300 mg/kg), GCSB-5 (600 mg/kg), celecoxib (60 mg/kg), or saline for four weeks, and nontreated control mice. The clinical severity of arthritis was scored. Nociceptive thresholds were measured by using a von Frey dynamic plantar analgesimeter. The MAPK pathway was evaluated in mouse synovium. The expression of channels associated with pain signaling was assessed by western blot and immunohistochemical staining. GCSB-5 treatment diminished the severity of clinical arthritis and increased the nociceptive threshold in mice with CIA. Celecoxib, a positive control drug, also showed comparable changes. Clinical arthritis scores were inversely related to mechanical thresholds. GCSB-5 administration decreased the levels of anti-type II collagen antibody and inflammatory cytokines in the sera of mice with CIA. Furthermore, ERK, p38 MAPK, and JNK phosphorylation were downregulated and TRPV1 and ASIC3 expression were decreased in the synovium of GCSB-5-treated mice compared to salinetreated mice. Interleukin-6-induced TRPV1 and ASIC3 upregulation were also inhibited by GCSB-5 in human RA fibroblast-like synoviocytes in vitro. GCSB-5 decreased inflammatory arthritis and pain in a murine model of RA. The results present evidence that GCSB-5 may be beneficial for relieving pain as well as decreasing inflammation in autoimmune arthritis, such as RA.