Collagen-induced Arthritis Research Articles

Sulfated hyaluronic acid gel for the treatment of rheumatoid arthritis in rats

Rheumatoid arthritis (RA) is a chronic autoimmune disease. NSAIDS, cyclophosphamide and glucocorticoid were commonly used to treat RA in clinical application, which long-term administration of these drugs caused serious adverse reactions. Therefore, sulfated hyaluronic acid (sHA) gel (SG) was prepared to firstly treat the RA and avoid the problem of toxic side effect caused by long-term application. In vitro evaluation showed that sHA inhibited the level of reactive oxygen species and TNF-α, IL-1β, and IL-6, and decreased the ratio of macrophage M1/M2 type, which exerted better anti-inflammatory capacity. In vivo studies showed that the injection of SG into the joint cavity of collagen-induced rheumatoid arthritis (CIA) rats could effectively treat joint swelling and reduce the level of inflammatory factors in the serum. Immunofluorescence showed that SG exerted its anti-inflammatory activity by decreasing the ratio of M1/M2 type macrophages in synovial tissue. Cartilage tissue sections showed that SG reduced bone erosion and elevated chondrocyte expression. These results confirmed that sHA is expected to be developed as a drug to treat or relieve RA, which could effectively regulate the level of macrophages in rat RA, alleviate the physiological state of inflammatory over-excitation, and improve its anti-inflammatory and antioxidant capacity.

Mechanism of Rhodiola rosea-Euonymus alatus drug pair against rheumatoid arthritis: Network pharmacology and experimental validation.

The present study aimed to explore the potential components and mechanisms of Rhodiola rosea-Euonymus alatus drug pair (TY) that ameliorate rheumatoid arthritis (RA). The main active components, core targets, and important pathways of TY against RA were predicted by network pharmacology analysis. The binding activity between the main active components and the core targets was verified by the molecular docking technique. Collagen-induced arthritis (CIA) rat model and tumor necrosis factor (TNF)-α-induced fibroblast-like synovial cells in human RA (HFLS-RA) model were established, respectively. The core targets were verified by cell counting kit-8 assay, hematoxylin eosin, enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and Western blot analysis, and the therapeutic effect of TY was evaluated. A total of 18 possible components and 34 core targets were obtained by network pharmacology, among which inflammatory response, phosphatidylinositide 3-kinases (PI3K)-AKT and MAPK pathways were involved in the therapeutic effect of TY on RA. The results of molecular docking showed that kaempferol and quercetin had high binding affinity to interleukin (IL)-1β, IL-6, matrix metalloproteinase (MMP)9, and TNF-α. In vivo and in vitro experiments showed that TY dose-dependently inhibited the proliferation of HFLS-RA cells induced by TNF-α, and significantly reduced the paw swelling and arthritis scores in CIA rats. At the same time, TY inhibited the production of inflammatory factors in CIA rat serum and TNF-α-induced HFLS-RA cells. It also decreased the expression of PI3K, phospho-protein kinase B, MMP1, MMP3, MMP9, and increased the protein and mRNA levels of tissue inhibitors of MMPs (TIMP)1 in synovial tissue. TY can inhibit the PI3K/AKT signaling pathway and regulate the balance between MMPs and TIMP, thus playing a therapeutic role in RA.

Withaferin A alleviates inflammation and joint injury in arthritic rats via elevating microRNA-1297 to target karyopherin alpha2.

Withaferin A (WFA) is a natural compound separated from the medicinal plant Withania somnifera. As reported, it has the potential to safely cure rheumatoid arthritis (RA) in animal models. Nevertheless, the action mechanism of WFA in treating RA has not been completely illuminated. The study was to explore the action and mechanism of WFA on arthritic rats. First, a collagen-induced arthritis rat model was established. WFA administration alleviated inflammation and injury in arthritic rats. Subsequently, fibroblast synovial cells (FLS) of arthritic rats were separated and cell proliferation and apoptosis abilities were tested. It was found that WFA was available to repress FLS cell proliferation and accelerate apoptosis. MicroRNA-1297 was downregulated in RA patients. Clinical correlation analysis suggested that miR-1297 in the serum of RA patients was negatively associated with pro-inflammatory factors interleukin (IL)-6, IL-17, tumor necrosis factor (TNF)-α, and RA diagnostic indexes (RF, DAS28). In the meantime, miR-1297 had superior diagnostic value in differentiating RA patients from healthy people. Karyopherin α2 (KPNA2) was the downstream target of miR-1297, while miR-1297 negatively modulated KPNA2 expression. Importantly, WFA further restrained KPNA2 expression via elevating miR-1297 in functional rescue experiments, thereby treating inflammation and injury in arthritic rats and repressing FLS cell proliferation and activation. In short, WFA alleviated inflammation and joint damage in arthritic rats via elevating miR-1297 to target KPNA2.

CP-25 inhibits the hyperactivation of rheumatic synoviocytes by suppressing the switch in Gαs-Gαi coupling to the β2-adrenergic receptor

In essence, the β2 adrenergic receptor (β2AR) plays an antiproliferative role by increasing the intracellular cyclic 3’,5’-adenosine monophosphate (cAMP) concentration through Gαs coupling, but interestingly, β2AR antagonists are able to effectively inhibit fibroblast-like synoviocytes (FLSs) proliferation, thus ameliorating experimental RA, indicating that the β2AR signalling pathway is impaired in RA FLSs via unknown mechanisms. The local epinephrine (Epi) level was found to be much higher in inflammatory joints than in normal joints, and high-level stimulation with Epi or isoproterenol (ISO) directly promoted FLSs proliferation and migration due to impaired β2AR signalling and cAMP production. By applying inhibitor of receptor internalization, and small interfering RNA (siRNA) of Gαs and Gαi, and by using fluorescence resonance energy transfer and coimmunoprecipitation assays, a switch in Gαs-Gαi coupling to β2AR was observed in inflammatory FLSs as well as in FLSs with chronic ISO stimulation. This Gαi coupling was then revealed to be initiated by G protein coupled receptor kinase 2 (GRK2) but not β-arrestin2 or protein kinase A-mediated phosphorylation of β2AR. Inhibiting the activity of GRK2 with the novel GRK2 inhibitor paeoniflorin-6′-O-benzene sulfonate (CP-25), a derivative of paeoniflorin, or the accepted GRK2 inhibitor paroxetine effectively reversed the switch in Gαs-Gαi coupling to β2AR during inflammation and restored the intracellular cAMP level in ISO-stimulated FLSs. As expected, CP-25 significantly inhibited the hyperplasia of FLSs in a collagen-induced arthritis (CIA) model (CIA FLSs) and normal FLSs stimulated with ISO and finally ameliorated CIA in rats. Together, our findings revealed the pathological changes in β2AR signalling in CIA FLSs, determined the underlying mechanisms and identified the pharmacological target of the GRK2 inhibitor CP-25 in treating CIA.7HWufKwpH5ZfY_hx8fyY6aVideo

Immunomodulatory Nanoparticles for Modulating Arthritis Flares.

Disease-modifying drugs have improved the treatment for autoimmune joint disorders, such as rheumatoid arthritis, but inflammatory flares are a common experience. This work reports the development and application of flare-modulating poly(lactic-co-glycolic acid)-poly(ethylene glycol)-maleimide (PLGA-PEG-MAL)-based nanoparticles conjugated with joint-relevant peptide antigens, aggrecan70-84 and type 2 bovine collagen256-270. Peptide-conjugated PLGA-PEG-MAL nanoparticles encapsulated calcitriol, which acted as an immunoregulatory agent, and were termed calcitriol-loaded nanoparticles (CLNP). CLNP had a ∼200 nm hydrodynamic diameter with a low polydispersity index. In vitro, CLNP induced phenotypic changes in bone marrow derived dendritic cells (DC), reducing the expression of costimulatory and major histocompatibility complex class II molecules, and proinflammatory cytokines. Bulk RNA sequencing of DC showed that CLNP enhanced expression of Ctla4, a gene associated with downregulation of immune responses. In vivo, CLNP accumulated in the proximal lymph nodes after intramuscular injection. Administration of CLNP was not associated with changes in peripheral blood cell numbers or cytokine levels. In the collagen-induced arthritis and SKG mouse models of autoimmune joint disorders, CLNP reduced clinical scores, prevented bone erosion, and preserved cartilage proteoglycan, as assessed by high-resolution microcomputed tomography and histomorphometry analysis. The disease protective effects were associated with increased CTLA-4 expression in joint-localized DC and CD4+ T cells but without generalized suppression of T cell-dependent immune response. The results support the potential of CLNP as modulators of disease flares in autoimmune arthropathies.

Hierarchical Microcarriers Loaded with Peptide Dendrimer‐Grafted Methotrexate for Rheumatoid Arthritis Treatment

Rheumatoid arthritis (RA) is one of the leading causes of disability due to the autoimmune destruction of synovial joints. Great efforts have been put into developing multifunctional drug delivery systems for delaying the progression of RA. Herein, a novel locally injectable, hierarchically structured delivery system with a hyaluronic acid (HA) microparticle and an MTX‐conjugated nanoparticle for promoted RA treatment is proposed. In this system, MTX is chemically grafted onto a peptide dendrimer‐based nanoparticle (G‐MTX). These nanoparticles are encapsulated inside HA microparticles (H‐G‐MTX) using microfluidics to realize the system. The G‐MTX can be released from the degradable HA microparticles in the acidic environment of inflamed RA joints. As the G‐MTX shows an enhanced intracellular delivery of the conjugated MTX, the H‐G‐MTX can reverse the dominant macrophage phenotype from M1 to M2. Through a collagen‐induced arthritis (CIA) rat model, the great therapeutic outcomes of this hierarchically structured delivery system are demonstrated, including inflammation reduction, cartilage protection, and bone mineral density promotion. These results indicate that the proposed hierarchical delivery system has potential clinical value in the treatment of RA and other diseases.

Effect of acupuncture on arthritic pathological injury in rats with type Ⅱ collagen-induced rheumatoid arthritis.

To observe the effect of acupuncture stimulation of "Yanglingquan"(GB34), "Zusanli"(ST36) and "Xuanzhong" (GB39) on arthritis index (AI), joint synovial membrane pathology, serum-related immunoinflammatory factors, and expressions of tumor suppressor gene mt-p53, nuclear factor kappa B (NF-κB) and peroxisome proliferator activated receptor gamma (PPARγ) in knee joint synovial tissue of rats with type Ⅱ collagen-induced arthritis (CIA), so as to explore its possible mechanisms underlying improvement of rheumatoid arthritis (RA). Male SD rats were used in the present study. The CIA model was established by subcutaneous injection of collagen emulsion (200 μL/rat) in the tail root region on the first day and repeat (100 μL/rat) once on the 9th day. Eighteen successful CIA rats were randomized into model, medication and acupuncture groups, with 6 rats in each group. Other 6 normal rats were used as the normal control group. For rats of the medication group, leflunomide (1.9 mg/kg) was administrated by gavage, once a day, and for rats of the acupuncture group, manual acupuncture stimulation was applied to bilateral GB34, ST36, GB39 for 30 min, once a day, for 12 weeks. The arthritis index (AI) score (0-4 points) was evaluated once every week. The contents of IL-6, IL-17 and TNF-α in the serum were determined by ELISA. Histopathological changes of the ankle joint were observed by H.E. staining. The protein and mRNA expression levels of mt-p53, NF-κB p65, and PPARγ in the knee joint synovial tissue were determined by Western blot and quantitative real time PCR, separately. Compared with the normal control group, the AI scores at different time-points after modeling, contents of serum TNF-α, IL-6 and IL-17, expression levels of mt-p53, NF-κB p65, PPARγ proteins and mRNAs were significantly increased in the model group (P<0.01, P<0.05). In comparison with the model group, the AI scores at the 10th week in the medication group and at the 3rd, 9th and 10th week in the acupuncture group, contents of serum TNF-α, IL-6 and IL-17, and the expression levels of mt-p53 and NF-κB p65 proteins in both medication and acupuncture groups, as well as mt-p53 and NF-κB p65 mRNAs in the medication group were apparently decreased (P<0.01, P<0.05), while the expression levels of PPARγ protein in both medication and acupuncture group and PPARγ mRNA in the medication group were significantly up-regulated (P<0.05, P<0.01). No significant differences were found between the acupuncture and medication groups in down-regulating the AI score and serum TNF-α, IL-6 and IL-17 contents. The effect of acupuncture was weaker than that of medication in down-regulating the expression of mt-p53 and NF-κB p65 proteins and mRNAs and in up-regulating PPARγ mRNA (P<0.01). H.E. results showed ankle cartilage hyperplasia, reduced joint cavity, mild fibroproliferation and inflammatory cell infiltration in the surrounding soft tissue of the ankle joint in rats of the model group, which was milder in both medication and acupuncture groups. Acupuncture stimulation can improve the degree of joint inflammation and swelling in CIA rats, which may be related to its effects in inhibiting the overexpression of immunoinflammatory factors in serum and regulating expression of mt-p53, NF-κB p65, PPARγ mRNAs and proteins in the synovial tissue.

Celastrol-loaded bovine serum albumin nanoparticles target inflamed neutrophils for improved rheumatoid arthritis therapy

Inflammatory neutrophils (INEs), motivated by cytokines, continue to migrate into the inflamed joints, driving the development of RA. Hence, inducing apoptosis of INEs to reduce recruitment at inflamed joints is an effective strategy for the treatment of RA. However, simply apoptotic INEs may trigger the release of neutrophil extracellular traps (NETs) and accelerate the inflammatory process. To overcome these drawbacks, an RGD-modified bovine serum albumin (BSA) nanoparticles (CBR NPs) was fabricated to selectively target INEs in situ for intracellular delivery of CLT. Studies have demonstrated that CBR NPs can selectively target circulating INEs and induce INEs apoptosis. Meanwhile, CBR NPs inhibited the activation of NETs via NF-κB pathway and the release of Cit-H3 thereby blocking the release process of NETs. In collagen-induced arthritis (CIA) mouse model, CBR NPs suppressed the inflammatory response, and reduced the toxic effects of CLT. In summary, this study shed light on an innovative approach to treat RA by inducing apoptosis of circulating INEs and inhibiting NETs. STATEMENT OF SIGNIFICANCE: RGD-modified bovine serum albumin (BSA) nanoparticles for delivering celastrol, abbreviated as CBR NPs, were constructed to inhibit the infiltration of circulating inflammatory neutrophils (INEs) into inflamed joints while inhibiting the release of NETs to alleviate tissue damage. CBR NPs were prepared for the first time to induce apoptosis of INEs; CBR NPs could inhibit the release of NETs while inducing apoptosis of INEs in vivo and vitro cellular experiments; CBR NPs had favorable anti-inflammatory effects and low toxicity side-effects in collagen-induced arthritis (CIA) mouse models. The application of nanotechnology to induce apoptosis of INEs while inhibiting the release of NETs was a promising approach for the treatment of RA.

Role of soluble epoxide hydrolase in the abnormal activation of fibroblast-like synoviocytes from patients with rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by enigmatic pathogenesis. Polyunsaturated fatty acids (PUFAs) are implicated in RA's development and progression, yet their exact mechanisms of influence are not fully understood. Soluble epoxide hydrolase (sEH) is an enzyme that metabolizes anti-inflammatory epoxy fatty acids (EpFAs), derivatives of PUFAs. In this study, we report elevated sEH expression in the joints of CIA (collagen-induced arthritis) rats, concomitant with diminished levels of two significant EpFAs. Additionally, increased sEH expression was detected in both the synovium of CIA rats and in the synovium and fibroblast-like synoviocytes (FLS) of RA patients. The sEH inhibitor TPPU attenuated the migration and invasion capabilities of FLS derived from RA patients and to reduce the secretion of inflammatory factors by these cells. Our findings indicate a pivotal role for sEH in RA pathogenesis and suggest that sEH inhibitors offer a promising new therapeutic strategy for managing RA.

Bibliometric analysis of trends in research of Tripterygium wilfordii Hook F for treating rheumatoid arthritis.

Tripterygium wilfordii Hook F (TwHF) has been widely used to relieve rheumatoid arthritis (RA) in many countries. However, a bibliometric analysis of published articles discussing this treatment has not been conducted. This study aimed to explore the current status and trends of TwHF for treating RA. Literature was extracted from the Science Citation Index Expanded Database of the Web of Science from January 1, 2013 to December 31, 2022. CiteSpace and the "bibliometrix" package were adopted to analyze the number of publications, countries, institutions, journals, authors, and keywords and to draw collaborative network maps. One hundred sixty-seven articles were identified. China has the most articles, followed by the United States. The China Academy of Chinese Medical Science had the study's most significant publications and the highest centrality. The author analysis combined with the analysis of the cited authors, the rank of Lin Na is in an important position. The Journal of Ethnopharmacology, Frontiers in Pharmacology has published the most relevant articles and is the hottest related journal. For keyword analysis, "classification," "criteria," "mechanism," and "methotrexate" were still being researched hot until 2022. Further investigation showed that "TNF-α," "proliferation," "endothelial growth factor," "NF-κB," and "collagen-induced arthritis" also remains research hotspot. Our results provide information on the research status, institutions, countries, authors, published journals, keywords related to using TwHF to treat RA, and theoretical support for further research.

Counteracting tryptophan metabolism alterations as a new therapeutic strategy for rheumatoid arthritis

ObjectivesAlterations in tryptophan (Trp) metabolism have been reported in inflammatory diseases, including rheumatoid arthritis (RA). However, understanding whether these alterations participate in RA development and can be considered putative therapeutic...

Efficacy and safety of 5-aminolevulinic acid in adult-onset Still's disease: A preclinical study in mice and a pilot study in humans

The study aimed to investigate the therapeutic effects of 5-aminolevulinic acid/sodium ferrous citrate (5-ALA/SFC) on adult-onset Still's disease (AOSD), specifically focusing on arthritis and macrophage activation syndrome (MAS). We used mouse models to assess the impact of 5-ALA/SFC on collagen-induced arthritis (CIA) and MAS induced by synthetic oligonucleotides containing CpG motifs (CpG-S-ODN). Additionally, we conducted a pilot study with AOSD patients receiving prednisolone (PSL) treatment and 5-ALA/SFC administration to evaluate its efficacy and safety. The 5-ALA/SFC group exhibited significantly lower joint scores in CIA mice. In CpG-S-ODN-treated mice, 5-ALA/SFC administration led to reduced hemophagocytosis and splenomegaly. The anti-inflammatory properties of 5-ALA/SFC were attributed to the suppression of CCL4 and CXCL10 production in monocytes and the induction of M2 macrophages. AOSD patients treated with 5-ALA/SFC demonstrated successful PSL tapering without adverse events. Collectively, the administration of 5-ALA/SFC showed promising potential in ameliorating arthritis and MAS in AOSD patients.

A novel single domain bispecific antibody targeting VEGF and TNF-α ameliorates rheumatoid arthritis

Anti-TNF-α therapy fails in 30% of patients, where TNF-α may not be the key causative factor in these patients. We developed a bispecific single-domain antibody block TNF-α and VEGF (V5-3).The experiments showed that V5-3 effectively activated proliferation and migration of RA-FLS and HUVEC, tube-forming role of HUVEC, and expression of inflammatory factors in vitro. Besides, the experiments indicated that the anti-RA activity of V5-3 was superior to Anbainuo in vivo. Application of V5-3 reduced the expression of inflammatory factors, extent of synovial inflammation and angiogenesis and attenuated the severity of autoimmune arthritis in collagen-induced arthritis (CIA) mice. Mechanistically, V5-3 suppressed p65, AKT and VEGFR2 phosphorylation, as well as production of TNF-α and VEGF in joint tissues. These results demonstrated that V5-3 displayed a superior effect of anti-RA, may be a new therapy to overcome the limitations of anti-TNF-α monoclonal antibody.

Targeting kinase ITK treats autoimmune arthritis via orchestrating T cell differentiation and function

IL-2 inducible T cell kinase (ITK) is critical in T helper subset differentiation and its inhibition has been suggested for the treatment of T cell-mediated inflammatory diseases. T follicular helper (Tfh), Th17 and regulatory T cells (Treg) also play important roles in the development of rheumatoid arthritis (RA), while the role of ITK in the development of RA and the intricate balance between effector T and regulatory T cells remains unclear. Here, we found that CD4+ T cells from RA patients presented with an elevated ITK activation. ITK inhibitor alleviated existing collagen-induced arthritis (CIA) and reduced antigen specific antibody production. Blocking ITK kinase activity interferes Tfh cell generation. Moreover, ITK inhibitor effectively rebalances Th17 and Treg cells by regulating Foxo1 translocation. Furthermore, we identified dihydroartemisinin (DHA) as a potential ITK inhibitor, which could inhibit PLC-γ1 phosphorylation and the progression of CIA by rebalancing Th17 and Treg cells. Out data imply that ITK activation is upregulated in RA patients, and therefore blocking ITK signal may provide an effective strategy to treat RA patients and highlight the role of ITK on the Tfh induction and RA progression.

Eicosanoid profiles in an arthritis model: Effects of a soluble epoxide hydrolase inhibitor

Rheumatoid arthritis is a common systemic inflammatory autoimmune disease characterized by damage to joints, inflammation and pain. It is driven by an increase of inflammatory cytokines and lipids mediators such as prostaglandins. Epoxides of polyunsaturated fatty acids (PUFAs) are lipid chemical mediators in a group of regulatory compounds termed eicosanoids. These epoxy fatty acids (EpFA) have resolutive functions but are rapidly metabolized by the soluble epoxide hydrolase enzyme (sEH) into the corresponding diols. The pharmacological inhibition of sEH stabilizes EpFA from hydrolysis, improving their half-lives and biological effects. These anti-inflammatory EpFA, are analgesic in neuropathic and inflammatory pain conditions. Nonetheless, inhibition of sEH on arthritis and the resulting effects on eicosanoids profiles are little explored despite the physiological importance. In this study, we investigated the effect of sEH inhibition on collagen-induced arthritis (CIA) and its impact on the plasma eicosanoid profile. We measured the eicosanoid metabolites by LC–MS/MS-based lipidomic analysis. The treatment with a sEH inhibitor significantly modulated 11 out of 69 eicosanoids, including increased epoxides 12(13)-EpODE, 12(13)-EpOME, 13-oxo-ODE, 15-HEPE, 20-COOH-LTB4 and decreases several diols 15,6-DiHODE, 12,13-DiHOME, 14,15-DiHETrE, 5,6-DiHETrE and 16,17-DiHDPE. Overall the inhibition of sEH in the rheumatoid arthritis model enhanced epoxides generally considered anti-inflammatory or resolutive mediators and decreased several diols with inflammatory features. These findings support the hypothesis that inhibiting the sEH increases systemic EpFA levels, advancing the understanding of the impact of these lipid mediators as therapeutical targets.

Herbal compound cepharanthine attenuates inflammatory arthritis by blocking macrophage M1 polarization

ObjectiveCepharanthine (CEP) is a drug candidate for tumor, viral infection, and some inflammatory diseases, but its effect on rheumatoid arthritis (RA) and the underlying mechanism are incompletely understood. MethodsCEP was administered intraperitoneally to a collagen-induced arthritis (CIA) model. Joints went radiological and histological examination and serum cytokines were examined with cytometry-based analysis. M1 macrophages were induced from THP-1 cells or mouse bone marrow-derived macrophages with LPS and IFN-γ. Bulk RNA-seq was performed on macrophage undergoing M1-polarizatioin. Western blotting was applied to determine pathways involved in monocyte chemotaxis and polarization. Glycolysis metabolites were measured by chemiluminescence while glycolytic enzymes were examined by quantitative PCR. ResultsWe found CEP significantly ameliorated synovial inflammation and joint destruction of CIA mice. It downregulated TNF-α levels in serum and in joints. The number of M1 macrophages were reduced in CEP-treated mice. In vitro, CEP inhibited monocyte chemotaxis to MCP-1 by downregulating CCR2 and reducing ERK1/2 signaling. Additionally, CEP suppressed M1 polarization of macrophages induced by LPS and IFN-γ. Genes involved in IFN-γ signaling, IL-6-JAK/STAT3 signaling, glycolysis, and oxidative phosphorylation process were downregulated by CEP. Several enzymes critically involved in glycolytic metabolism were suppressed by CEP, which resulted in reduced citrate in M1-polarizing macrophages. The inhibitory effect of CEP on macrophage polarization might be attributed to the blockage of TLRs-MyD88/IRAK4-IRF5 signaling pathway together with suppression of overactivated glycolytic metabolism in M1-polarizing macrophages. ConclusionCEP attenuated joint inflammation by suppressing monocyte chemotaxis and proinflammatory differentiation. It has the potential to be developed into a complementary or alternative therapy for RA.

Highly Efficient Oral Iguratimod/Polyvinyl Alcohol Nanodrugs Fabricated by High-Gravity Nanoprecipitation Technique for Treatment of Rheumatoid Arthritis.

Rheumatoid arthritis (RA), a systemic autoimmune disease, poses a significant human health threat. Iguratimod (IGUR), a novel disease-modifying antirheumatic drug (DMARD), has attracted great attention for RA treatment. Due to IGUR's hydrophobic nature, there's a pressing need for effective pharmaceutical formulations to enhance bioavailability and therapeutic efficacy. The high-gravity nanoprecipitation technique (HGNPT) emerges as a promising approach for formulating poorly water-soluble drugs. In this study, IGUR nanodrugs (NanoIGUR) are synthesized using HGNPT, with a focus on optimizing various operational parameters. The outcomes revealed that HGNPT enabled the continuous production of NanoIGUR with smaller sizes (ranging from 300 to 1000 nm), more uniform shapes, and reduced crystallinity. In vitro drug release tests demonstrated improved dissolution rates with decreasing particle size and crystallinity. Notably, in vitro and in vivo investigations showcased NanoIGUR's efficacy in inhibiting synovial fibroblast proliferation, migration, and invasion, as well as reducing inflammation in collagen-induced arthritis. This study introduces a promising strategy to enhance and broaden the application of poorly water-soluble drugs.

Voluntary wheel running from early adolescence reduces disease progression, and anxiety- and depression-related symptoms in an adult male mouse model of rheumatoid arthritis

Rheumatoid arthritis (RA) is a multifactorial autoimmune disease that progressively destroys synovial joints and leads to chronic systemic inflammation. This autoimmune disorder is associated with increased anxiety- and depression-related symptoms, which reduces quality of life. Clinical and experimental evidence suggests that higher physical activity from early adolescence may prevent chronic diseases and reduce the risk of mental health problems in adulthood. This study aimed to assess whether voluntary wheel running from early adolescence can decrease clinical symptoms, anxiety- and depression-related behaviors in adult mice with rheumatoid arthritis. Adolescent male mice were exposed to voluntary wheel running until adulthood and got collagen-induced arthritis. We measured body weight, the thickness of the hind paw and knee joint (clinical signs), anxiety- and depression-related behaviors, serum testosterone, and cytokines (IFN-γ IL-1β, IL-6, TNF-α, IL-10). The findings showed that collagen-induced arthritis resulted in anxious-like behavior, increased anhedonia, elevated IL-6, IL-1β, TNF-α, and IFN-γ, and decreased testosterone levels in the serum of mice. However, no change was observed in behavioral despair. We found that higher physical activity from early adolescence significantly reduced the severity of clinical signs, anxiety- and anhedonia-like behaviors, and decreased behavioral despair in RA-induced mice. In addition, the running wheel exposure normalized RA-induced abnormalities in testosterone and inflammatory cytokines in mice. Altogether, this study suggests that higher physical activity from early adolescence may make mice less vulnerable or resistant to RA-induced clinical symptoms and anxiety- and depression-related behaviors by changing testosterone and inflammatory cytokines productions in adulthood.

Prolonged administration of total glucosides of paeony improves intestinal immune imbalance and epithelial barrier damage in collagen-induced arthritis rats based on metabolomics-network pharmacology integrated analysis.

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovial inflammation and joint damage with complex pathological mechanisms. In recent years, many studies have shown that the dysregulation of intestinal mucosal immunity and the damage of the epithelial barrier are closely related to the occurrence of RA. Total glucosides of paeony (TGP) have been used clinically for the treatment of RA in China for decades, while the pharmacological mechanism is still uncertain. The purpose of this study was to investigate the regulatory effect and mechanism of TGP on intestinal immunity and epithelial barrier in RA model rats. The results showed that TGP alleviated immune hyperfunction by regulating the ratio of CD3+, CD4+ and CD8+ in different lymphocyte synthesis sites of the small intestine, including Peyer's patches (PPs), intraepithelial lymphocytes (IELs), and lamina propria lymphocytes (LPLs). Specially, TGP first exhibited immunomodulatory effects on sites close to the intestinal lumen (IELs and LPLs), and then on PPs far away from the intestinal lumen as the administration time prolonged. Meanwhile, TGP restores the intestinal epithelial barrier by upregulating the ratio of villi height (V)/crypt depth (C) and expression of tight junction proteins (ZO-1, occludin). Finally, the integrated analysis of metabolomics-network pharmacology was also used to explore the possible regulation mechanism of TGP on the intestinal tract. Metabolomics analysis revealed that TGP reversed the intestinal metabolic profile disturbance in CIA rats, and identified 32 biomarkers and 163 corresponding targets; network pharmacology analysis identified 111 potential targets for TGP to treat RA. By intersecting the results of the two, three key targets such as ADA, PNP and TYR were determined. Pharmacological verification experiments showed that the levels of ADA and PNP in the small intestine of CIA rats were significantly increased, while TGP significantly decreased their ADA and PNP levels. In conclusion, purine metabolism may play an important role in the process of TGP improving RA-induced intestinal immune imbalance and impaired epithelial barrier.

Network pharmacology and experimental validation methods to reveal the active compounds and hub targets of Curculigo orchioides Gaertn in rheumatoid arthritis

BackgroundRheumatoid arthritis (RA) is an autoimmune disease that can lead to joint destruction and deformity. Curculigo orchioides Gaertn (CO) was previously revealed to play a significant role in RA treatment. However, the main active ingredients and molecular mechanisms of CO in regulating RA are still unclear.MethodsThe active ingredients of CO were obtained from the Traditional Chinese Medicine Systems Pharmacology database and published literature. The targets corresponding to these compounds and the targets linked to RA were collected from public databases. The “ingredient-target” and “protein–protein interaction” networks were constructed to screen the main active ingredients and hub targets of CO in the treatment of RA. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment assays were used to elucidate the potential pharmacological mechanism of CO in RA. Molecular docking was performed to detect the binding between the main active ingredients and hub targets. Collagen-induced arthritis rats were used to validate the hub targets of CO against RA.ResultsNetwork pharmacological topology analysis showed that caffeine, 2,4-dichloro-5-methoxy-3-methylphenol, curculigoside, orcinol glucoside, and orcin were the main active ingredients of CO, and matrix metalloproteinase 9 (MMP9), transcription factor AP-1 (JUN), prostaglandin-endoperoxide synthase 2 (PTGS2), brain-derived neurotrophic factor, and receptor-type tyrosine-protein phosphatase C were the hub targets of CO for RA treatment. Molecular docking revealed that curculigoside and orcinol glucoside had effective binding potential with MMP9, JUN, and PTGS2, respectively. In vivo experiments demonstrated that CO alleviated RA symptoms and inhibited the expression of MMP9, JUN, and PTGS2 proteins.ConclusionsOur study demonstrates the main active ingredients and potential targets of CO against RA, laying an experimental foundation for the development and application of CO as an anti-RA drug.