[The Miao medicine Sidaxue alleviates rheumatoid arthritis in rats possibly by downregulating matrix metalloproteinases].

OBJECTIVE: To explore the inhibitory effect of Sidaxue, a traditional Miao herbal medicine formula, on articular bone and cartilage destruction and synovial neovascularization in rats with collagen-induced arthritis (CIA). METHODS: In a SD rat model of CIA, we tested the effects of daily gavage of Sidaxue at low, moderate and high doses (10, 20, and 40 g/kg, respectively) for 21 days, with Tripterygium glycosides (GTW) as the positive control, on swelling in the hind limb plantar regions by arthritis index scoring. Pathologies in joint synovial membrane of the rats were observed with HE staining, and serum TNF-α and IL-1ß levels were detected with ELISA. The expressions of NF-κB p65, matrix metalloproteinase 1 (MMP1), MMP2 and MMP9 at the mRNA and protein levels in the synovial tissues were detected using real-time PCR and Western blotting. Network pharmacology analysis was conducted to identify the important target proteins in the pathways correlated with the therapeutic effects of topical Sidaxue treatment for RA, and the core target proteins were screened by topological analysis. RESULTS: Treatment with GTW and Sidaxue at the 3 doses all significantly alleviated plantar swelling, lowered arthritis index scores, improved cartilage and bone damage and reduced neovascularization in CIA rats (P<0.05), and the effects of Sidaxue showed a dose dependence. Both GTW and Sidaxue treatments significantly lowered TNF-α, IL-1ß, NF-κB p65, MMP1, MMP2, and MMP9 mRNA and protein expressions in the synovial tissues of CIA rats (P<0.05). Network pharmacological analysis identified MMPs as the core proteins associated with topical Sidaxue treatment of RA. CONCLUSION: Sidaxue alleviates articular bone and cartilage damages and reduces synovial neovascularization in CIA rats possibly by downregulating MMPs via the TNF-α/IL-1ß/NF-κB-MMP1, 2, 9 signaling pathway, and MMPs probably plays a key role in mediating the effect of Sidaxue though the therapeutic pathways other than oral administration.

Gut microbial metabolite targets HDAC3-FOXK1-interferon axis in fibroblast-like synoviocytes to ameliorate rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease. Early studies hold an opinion that gut microbiota is environmentally acquired and associated with RA susceptibility. However, accumulating evidence demonstrates that genetics also shape the gut microbiota. It is known that some strains of inbred laboratory mice are highly susceptible to collagen-induced arthritis (CIA), while the others are resistant to CIA. Here, we show that transplantation of fecal microbiota of CIA-resistant C57BL/6J mice to CIA-susceptible DBA/1J mice confer CIA resistance in DBA/1J mice. C57BL/6J mice and healthy human individuals have enriched B. fragilis than DBA/1J mice and RA patients. Transplantation of B. fragilis prevents CIA in DBA/1J mice. We identify that B. fragilis mainly produces propionate and C57BL/6J mice and healthy human individuals have higher level of propionate. Fibroblast-like synoviocytes (FLSs) in RA are activated to undergo tumor-like transformation. Propionate disrupts HDAC3-FOXK1 interaction to increase acetylation of FOXK1, resulting in reduced FOXK1 stability, blocked interferon signaling and deactivation of RA-FLSs. We treat CIA mice with propionate and show that propionate attenuates CIA. Moreover, a combination of propionate with anti-TNF etanercept synergistically relieves CIA. These results suggest that B. fragilis or propionate could be an alternative or complementary approach to the current therapies.

Epstein-Barr Virus DNA Exacerbates Arthritis in a Mouse Model via Toll-like Receptor 9.

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

Discovery of novel diaryl substituted isoquinolin-1(2H)-one derivatives as hypoxia-inducible factor-1 signaling inhibitors for the treatment of rheumatoid arthritis.

Since synovial hypoxic microenvironment significantly promotes the pathological progress of rheumatoid arthritis (RA), hypoxia-inducible factor 1 (HIF-1) has been emerged as a promising target for the development of novel therapeutic agents for RA treatment. In this study, we designed and synthesized a series of diaryl substituted isoquinolin-1(2H)-one derivatives as HIF-1 signaling inhibitors using scaffold-hopping strategy. By modifying the substituents on N-atom and 6-position of isoquinolin-1-one, we discovered compound 17q with the most potent activities against HIF-1 (IC50 = 0.55 µM) in a hypoxia-reactive element (HRE) luciferase reporter assay. Further pharmacological studies revealed that 17q concentration-dependently blocked hypoxia-induced HIF-1α protein accumulation, reduced inflammation response, inhibited cellular invasiveness and promoted VHL-dependent HIF-1α degradation in human RA synovial cell line. Moreover, 17q improved the pathological injury of ankle joints, decreased angiogenesis and attenuated inflammation response in the adjuvant-induced arthritis (AIA) rat model, indicating the promising therapeutic potential of compound 17q as an effective HIF-1 inhibitor for RA therapy.

Acupuncture alleviates inflammatory pain by activating CXCL1/CXCR2 signaling in the primary somatosensory cortex in adjuvant induced arthritis rats. / S1脑区CXCL1/CXCR2å‚ä¸Žé’ˆåˆºæ”¹å–„ä½å‰‚æ€§å ³èŠ‚ç‚Žå¤§é¼ ç‚Žæ€§ç—›çš„ä½œç”¨æœºåˆ¶.

OBJECTIVES: To observe whether acupuncture up-regulates chemokine CXC ligand 1 (CXCL1) in the brain to play an analgesic role through CXCL1/chemokine CXC receptor 2 (CXCR2) signaling in adjuvant induced arthritis (AIA) rats, so as to reveal its neuro-immunological mechanism underlying improvement of AIA. METHODS: BALB/c mice with relatively stable thermal pain reaction were subjected to planta injection of complete Freund adjuvant (CFA) for establishing AIA model, followed by dividing the AIA mice into simple AF750 (fluorochrome) and AF750+CXCL1 groups (n=2 in each group). AF750 labeled CXCL1 recombinant protein was then injected into the mouse's tail vein to induce elevation of CXCL1 level in blood for simulating the effect of acupuncture stimulation which has been demonstrated by our past study. In vivo small animal imaging technology was used to observe the AF750 and AF750+CXCL1-labelled target regions. After thermal pain screening, the Wistar rats with stable pain reaction were subjected to AIA modeling by injecting CFA into the rat's right planta, then were randomized into model and manual acupuncture groups (n=12 in each group). Other 12 rats that received planta injection of saline were used as the control group. Manual acupuncture (uniform reinforcing and reducing manipulations) was applied to bilateral "Zusanli" (ST36) for 4×2 min, with an interval of 5 min between every 2 min, once daily for 7 days. The thermal pain threshold was assessed by detecting the paw withdrawal latency (PWL) using a thermal pain detector. The contents of CXCL1 in the primary somatosensory cortex (S1), medial prefrontal cortex, nucleus accumbens, amygdala, periaqueductal gray and rostroventromedial medulla regions were assayed by using ELISA, and the expression levels of CXCL1, CXCR2 and mu-opioid receptor (MOR) mRNA in the S1 region were detected using real time-quantitative polymerase chain reaction. The immune-fluorescence positive cellular rate of CXCL1 and CXCR2 in S1 region was observed after immunofluorescence stain. The immunofluorescence double-stain of CXCR2 and astrocyte marker glial fibrillary acidic protein (GFAP) or neuron marker NeuN or MOR was used to determine whether there is a co-expression between them. RESULTS: In AIA mice, results of in vivo experiments showed no obvious enrichment signal of AF750 or AF750+CXCL1 in any organ of the body, while in vitro experiments showed that there was a stronger fluorescence signal of CXCL1 recombinant protein in the brain. In rats, compared with the control group, the PWL from day 0 to day 7 was significantly decreased (P<0.01) and the expression of CXCR2 mRNA in the S1 region significantly increased in the model group (P<0.05), while in comparison with the model group, the PWL from day 2 to day 7, CXCL1 content, CXCR2 mRNA expression and CXCR2 content, and MOR mRNA expression in the S1 region were significantly increased in the manual acupuncture group (P<0.05, P<0.01). Immunofluorescence stain showed that CXCR2 co-stained with NeuN and MOR in the S1 region, indicating that CXCR2 exists in neurons and MOR-positive neurons but not in GFAP positive astrocytes. CONCLUSIONS: Acupuncture can increase the content of CXCL1 in S1 region, up-regulate CXCR2 on neurons in the S1 region and improve MOR expression in S1 region of AIA rats, which may contribute to its effect in alleviating inflammatory pain.

Phlorizin Regulates Synovial Hyperplasia and Inflammation in Rats With Rheumatoid Arthritis by Regulating the mTOR Pathway.

BACKGROUND/AIM: Rheumatoid arthritis (RA) is an inflammatory autoimmune disease, and management of it is still a challenge. The present investigation assessed the potential preventive effect of phlorizin on rats with RA. MATERIALS AND METHODS: A total of 40 healthy Wistar rats were used for this study. Bovine type II collagen and Freund's incomplete adjuvant (1:1 and 1 mg/ml) were administered on days 1 and 8 of the protocol to induce RA in rats; treatment with phlorizin at 60 or 120 mg/kg was started after the 4th week of the protocol, and its effect on inflammation, level of inflammatory cytokines, and expression of proteins were estimated in RA rats. Moreover, an in vitro study was performed on fibroblast-like synoviocytes (FLSs), and the effects of phlorizin on proliferation, apoptosis, and expression of the mechanistic target of rapamycin kinase pathway protein after stimulating these cells with tumor necrosis factor α (TNF-α) were estimated. RESULTS: The data obtained from the study indicate that phlorizin has the potential to mitigate inflammation and enhance weight management in rats with RA induced by bovine type II collagen (CII). The level of inflammatory cytokines in the serum and the expression of protein kinase B (AKT), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), and mechanistic target of rapamycin kinase (mTOR) proteins in the joint tissue were reduced in phlorizin-treated rats with RA. In this investigation, phlorizin was shown to reverse the histological abnormalities in the joint tissue of rats with RA. The in-vitro study showed that phlorizin reduced proliferation and had no apoptotic effect on TNF-α-stimulated FLSs. Expression of AKT, PI3K, and mTOR proteins was also down-regulated in phlorizin-treated TNF-α-stimulated FLSs. CONCLUSION: Phlorizin protects against inflammation and reduces injury to synovial tissues in RA by modulating the AKT/PI3K/mTOR pathway.

Macrophage-derived mir-100-5p orchestrates synovial proliferation and inflammation in rheumatoid arthritis through mTOR signaling.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by synovial inflammation, causing substantial disability and reducing life quality. While macrophages are widely appreciated as a master regulator in the inflammatory response of RA, the precise mechanisms underlying the regulation of proliferation and inflammation in RA-derived fibroblast-like synoviocytes (RA-FLS) remain elusive. Here, we provide extensive evidence to demonstrate that macrophage contributes to RA microenvironment remodeling by extracellular vesicles (sEVs) and downstream miR-100-5p/ mammalian target of rapamycin (mTOR) axis. RESULTS: We showed that bone marrow derived macrophage (BMDM) derived-sEVs (BMDM-sEVs) from collagen-induced arthritis (CIA) mice (cBMDM-sEVs) exhibited a notable increase in abundance compared with BMDM-sEVs from normal mice (nBMDM-sEVs). cBMDM-sEVs induced significant RA-FLS proliferation and potent inflammatory responses. Mechanistically, decreased levels of miR-100-5p were detected in cBMDM-sEVs compared with nBMDM-sEVs. miR-100-5p overexpression ameliorated RA-FLS proliferation and inflammation by targeting the mTOR pathway. Partial attenuation of the inflammatory effects induced by cBMDM-sEVs on RA-FLS was achieved through the introduction of an overexpression of miR-100-5p. CONCLUSIONS: Our work reveals the critical role of macrophages in exacerbating RA by facilitating the transfer of miR-100-5p-deficient sEVs to RA-FLS, and sheds light on novel disease mechanisms and provides potential therapeutic targets for RA interventions.

Macrophage-derived human resistin promotes perivascular adipose tissue dysfunction in experimental inflammatory arthritis.

Cardiovascular disease (CVD) is the leading cause of death in rheumatoid arthritis (RA). Resistin is an adipokine that induces adipose tissue inflammation and activation of monocytes/macrophages via adenylate cyclase-associated protein-1 (CAP1). Resistin levels are increased in RA and might cause perivascular adipose tissue (PVAT) dysfunction, leading to vascular damage and CVD. This study aimed to investigate the role of resistin in promoting PVAT dysfunction by increasing local macrophage and inflammatory cytokines content in antigen-induced arthritis (AIA). Resistin pharmacological effects were assessed by using C57Bl/6J wild-type (WT) mice, humanized resistin mice expressing human resistin in monocytes-macrophages (hRTN+/-/-), and resistin knockout mice (RTN-/-) with AIA and respective controls. We investigated AIA disease activity and functional, cellular, and molecular parameters of the PVAT. Resistin did not contribute to AIA disease activity and its concentrations were augmented in the PVAT and plasma of WT AIA and hRTN+/-/- AIA animals. In vitro exposure of murine arteries to resistin impaired vascular function by decreasing the anti-contractile effect of PVAT. WT AIA mice and hRTN+/-/- AIA mice exhibited PVAT dysfunction and knockdown of resistin prevented it. Macrophage-derived cytokines, markers of types 1 and 2 macrophages, and CAP1 expression were increased in the PVAT of resistin humanized mice with AIA, but not in knockout mice for resistin. This study reveals that macrophage-derived resistin promotes PVAT inflammation and dysfunction regardless of AIA disease activity. Resistin might represent a translational target to reduce RA-driven vascular dysfunction and CVD.

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

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

Flavipin from fungi as a potential inhibitor of rheumatoid arthritis signaling molecules.

Flavipin, a fungal lower molecular weight biomolecule (MW 196.16 g/mol), has not been yet extensively studied for beneficial preclinical and clinical applications. In recent years, various preclinical mouse models including adjuvant-induced arthritis (AIA) were employed to understand mechanisms associated with Rheumatoid arthritis (RA) and to develop new therapeutic drugs. In the current study, we studied the inhibitory effect of Flavipin on major signaling molecules involved in the inflammatory response during RA using both in-silico virtual interaction and in vivo mouse model of AIA. Our in-silico results clarified that Flavipin interacts with the tumor necrosis factor alpha (TNF-α) through conventional hydrogen binding (H-H) at one of TNF-α critical amino acids tyrosine residues, Tyr119, with binding energy (b.e.) -5.9. In addition, Flavipin binds to ATP-binging sites of the Jesus kinases, JAK1, JAK2 and JAK3, through H-H (b. e. between -5.8 and -6.1) and then it may inhibit JAKs, regulators of RA signaling molecules. Moreover, our molecular dynamics stimulation for the docked TNF-α/Flavipin complex confirmed the specificity and the stability of the interaction. In vitro, Flavipin is not toxic to normal cells at doses below 50 µM (its IC50 in normal fibroblast cell line was above 100 µM). However, in vivo, the arthritis score and hind paw oedema parameters were modulated in Flavipin treated mice. Consistent with the in-silico results the levels of the TNF-α, the nuclear transcription factor kappaB (NF-κB) and the signal transduction and activator of transcription (STAT3, downstream of JAKs) were modulated at joint tissues of the hind-paw of Flavipin/AIA treated mice. Our data suggest Flavipin as a potential therapeutic agent for arthritis can inhibit RA major signaling molecules.

Engineered Exosomes Loaded with Triptolide: An Innovative Approach to Enhance Therapeutic Efficacy in Rheumatoid Arthritis.

OBJECTIVES: Exosomes are small, membrane-bound vesicles secreted by cells into the extracellular environment. They play a crucial role in various biological processes, including immune response, cell-to-cell signaling, and tumor progression. Exosomes have attracted attention as potential targets for therapeutic intervention, drug delivery, and biomarker detection. In this study, we aimed to isolate exosomes from human RA fibroblasts (hRAF-Exo) and load them with triptolide (TP) to generate engineered exosomes (hRAF-Exo@TP). METHODS: Transmission electron microscopy, particle size analysis, and western blotting for protein detection were employed to characterize hRAF-Exo. Furthermore, a murine model of collagen-induced arthritis (CIA) was employed to observe the distinct affinity of hRAF-Exo@TP towards the afflicted area. RESULTS: Cellular experiments demonstrated the inhibitory effect of hRAF-Exo@TP on the proliferative activity of human RA fibroblasts. Additionally, it exhibited remarkable selectivity for lesion sites in a CIA mouse model. CONCLUSION: Exosomes loaded with TP may enhance the therapeutic effects on RA in mice. Our study provides a promising avenue for the treatment of RA in the future.

Dietary oleacein, a secoiridoid from extra virgin olive oil, prevents collagen-induced arthritis in mice.

Olacein (OLA), one of the main secoiridoids derived from extra virgin olive oil (EVOO), has been shown to modulate oxidative and inflammatory responses in various pathological conditions; however, its potential benefit in joint disorders such as rheumatoid arthritis (RA) is unknown. Therefore, this study was designed to evaluate the preventive role of the effects of an OLA-supplemented diet in the murine model of collagen-induced arthritis (CIA), delving into the possible mechanisms and signaling pathways involved. Animals were fed an OLA-enriched preventive diet for 6 weeks prior to CIA induction and until the end of the experimental time course. On day 43 after the first immunization, mice were sacrificed: blood was collected, and paws were histologically and biochemically processed. Dietary OLA prevented collagen-induced rheumatic bone, joint and cartilage conditions. Circulating matrix metalloproteinase (MMP)-3 and proinflammatory cytokine (IL-6, IL-1ß, TNF-α, IL-17) levels were significantly decreased in the joint, as well as MMP-9 and cathepsin-K (CatK) expression in secoiridoid-fed animals. In addition, dietary OLA was able to decrease COX-2, mPGES-1 and iNOS protein expressions and, also, PGE2 levels. The mechanisms possibly involved in these protective effects could be related to the activation of the Nrf-2/HO-1 axis and the inhibition of proinflammatory signaling pathways, including JAK-STAT, MAPKs and NF-κB, involved in the production of inflammatory and oxidative mediators. These results support the interest of OLA, as a nutraceutical intervention, in the management of RA.

The therapeutic effect of Loranthus parasiticus lignan derivatives on collagen-induced arthritis in rats through the SHBG/NFκB pathway.

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

Berberine modulates the immunometabolism and differentiation of CD4+ T cells alleviating experimental arthritis by suppression of M1-exo-miR155.

BACKGROUND: The inflammatory cascade mediated by macrophages and T cells is considered to be an important factor in promoting the progression of rheumatoid arthritis (RA). Our previous study found that berberine (BBR) can therapeutically impact adjuvant arthritis (AA) in rats through the regulation of macrophage polarization and the balance of Th17/Treg. However, whether BBR's effects on CD4+T cells response are related to its suppression of M1 macrophage still unclear. PURPOSE: The study aimed to estimate the mechanism of BBR in regulating the immunometabolism and differentiation of CD4+T cells are related to exosome derived from M1-macrophage (M1-exo). STUDY-DESIGN/METHODS: Mice model of collagen-induced arthritis (CIA) was established to investigate the antiarthritic effect of BBR was related with regulation of M1-exo to balance T cell subsets. Bioinformatics analysis using the GEO database and meta-analysis. In vitro, we established the co-culture system involving M1-exo and CD4+ T cells to examine whether BBR inhibits CD4+T cell activation and differentiation by influencing M1-exo-miR155. Exosome was characterized using transmission electron microscopy and western blot analysis, macrophage and CD4+T cell subpopulation were detected by flow cytometry. Further, the metabolic profiles of CD4+T cells were assessed by ECAR, OCR, and the level of glucose, lactate, intracellular ATP. RESULT: BBR reinstates CD4+ T cell homeostasis and reduces miR155 levels in both M1-exo and CD4+ T cells obtained from mice with CIA. In vitro, we found exosomes are indispensable for M1-CM on T lymphocyte activation and differentiation. BBR reversed M1-exo facilitating the activation and differentiation of CD4+T cells. Furthermore, BBR reversed glycolysis reprogramming of CD4+T cells induced by M1-exo, while these regulation effects were significantly weakened by miR155 mimic. CONCLUSION: The delivery of miR-155 by M1-exo contributes to CD4+ T cell immunometabolism dysfunction, a process implicated in the development of RA. The anti-arthritic effect of BBR is associated with the suppression of glycolysis and the disruption of CD4+ T cell subsets balance, achieved by reducing the transfer of M1-exo-miR155 into T cells.

Study on the mechanism of action of Wu Mei Pill in inhibiting rheumatoid arthritis through TLR4-NF-κB pathway.

BACKGROUND: Wu Mei Pills (WMP) is a traditional Chinese medication that exhibits considerable anti-inflammatory effects. While WMP has been documented for its efficacy in treating RA, its mechanism of action on the condition remains unestablished. METHODS: The chemical composition of WMP was analyzed through UPLC-MS. Next, the enzyme-linked immunosorbent assay, cell scratch, Transwell, and Western blotting techniques were used to investigate its intrinsic mechanism. Lastly, the effect of WMP in inhibiting RA was explored by applying it to CIA rats. RESULT: UPLC-MS analysis detected 181 compounds in WMP. RA-FLS migration and invasion mechanisms were significantly hindered by serum containing WMP (2%, 8%). Moreover, WMP (0.5 g/kg, 2 g/kg) restricted arthritis and immune organ indices in CIA rats with type II collagen-induced rheumatoid arthritis by blocking TLR4-NF-κB inflammatory pathway activation. CONCLUSIONS: WMP is valuable in mitigating the course of RA through inhibiting the classical TLR4-NF-κB inflammatory pathway and reducing the secretion of inflammatory factors in the serum of RA-FLS and CIA rats. Moreover, it regulates the dynamic balance of MMP-2/TIMP-2, MMP-9/TIMP-1, modulates the mechanism of RA-FLS invasion, and safeguards articular cartilage tissues in RA.

Ingenious Synergy of a Pathology-Specific Biomimetic Multifunctional Nanoplatform for Targeted Therapy in Rheumatoid Arthritis.

Based on the pathological characteristics of rheumatoid arthritis, including the overproduction of reactive oxygen species (ROS), inflammatory responses, and osteoclast differentiation, a biomimetic multifunctional nanomedicine (M-M@I) is designed. Iguratimod (IGU) is loaded, which inhibits inflammatory responses and osteoclast differentiation, into mesoporous polydopamine (MPDA), which scavenges ROS. Subsequently, the nanoparticles are coated with a cell membrane of macrophages to achieve actively targeted delivery of the nanoparticles to inflamed joints. It is shown that the M-M@I nanoparticles are taken up well by lipopolysaccharide-induced RAW 264.7 macrophages or bone marrow-derived macrophages (BMDMs). In vitro, the M-M@I nanoparticles effectively scavenge ROS, downregulate genes related to inflammation promotion and osteoclast differentiation, and reduce the proinflammatory cytokines and osteoclast-related enzymes. They also reduce the polarization of macrophages to a pro-inflammatory M1 phenotype and inhibit differentiation into osteoclasts. In mice with collagen-induced arthritis, the M-M@I nanoparticles accumulate at arthritic sites and circulate longer, significantly mitigating arthritis symptoms and bone destruction. These results suggest that the pathology-specific biomimetic multifunctional nanoparticles are effective against rheumatoid arthritis, and they validate the approach of developing multifunctional therapies that target various pathological processes simultaneously.

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.

Knockdown of Galectin-9 alleviates rheumatoid arthritis through suppressing TNF-α-induced activation of fibroblast-like synoviocytes.

The role of Galectin-9 (Gal-9) in the pathogenesis of rheumatoid arthritis (RA) remains unclear. This study aimed to investigate the mechanism of action and therapeutic potential of Gal-9 in RA. We detected Gal-9 expression in clinical samples, explored the mechanism of function of Gal-9 by knockdown and overexpression in fibroblast-like synoviocytes (FLSs), and further verified it in collagen-induced arthritis (CIA) model. We found that the levels of Gal-9 were considerably elevated in RA synovium than in osteoarthritis (OA) patients. A substantial decrease of Gal-9 was demonstrated after tumor necrosis factor (TNF-α) inhibitor treatment in the plasma of patients with RA. Additionally, transcriptome sequencing revealed that Gal-9 was involved in the regulation of the TNF-α pathway. Gal-9 was considerably upregulated after TNF-α stimulation in FLSs, and knockdown of Gal-9 substantially inhibited TNF-α activated proliferation, migration and inflammatory response. According to cell transcriptome sequencing results, we further confirmed that Gal-9 could achieve these effects by interacting with MAFB and affecting PI3K/AKT/mTOR pathway. Finally, we knocked down Gal-9 on the CIA model and found that it could alleviate the progression of arthritis. In conclusion, our study revealed that the knockdown of Gal-9 could inhibited TNF-α induced activation in RA through MAFB, PI3K/AKT/mTOR.

B7-H3 promotes angiogenesis in rheumatoid arthritis.

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

Efficient delivery of the lncRNA LEF1-AS1 through the antibody LAIR-1 (CD305)-modified Zn-Adenine targets articular inflammation to enhance the treatment of rheumatoid arthritis.

BACKGROUNDS: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by synovial hyperplasia. Maintaining a balance between the proliferation and apoptosis of rheumatoid arthritis synovial fibroblasts (RASFs) is crucial for preventing the erosion of bone and cartilage and, ultimately, mitigating the progression of RA. We found that the lncRNA LEF1-AS1 was expressed at low levels in the RASFs and inhibited their abnormal proliferation by targeting PIK3R2 protein and regulating the PI3K/AKT signal pathway through its interaction with miR-30-5p. In this study, we fabricated a nano-drug delivery system for LEF1-AS1 using Zn-Adenine nanoparticles (NPs) as a novel therapeutic strategy against RA. METHODS: The expression levels of LEF1-AS1, miR-30-5p, PIK3R2, p-PI3K, and p-AKT were detected in the primary RASFs and a human fibroblast-like synovial cell line (HFLS). Zn-Adenine nanoparticles (NPs) were functionalized with anti-CD305 antibody to construct (Zn-Adenine)@Ab. These NPs were then loaded with LEF1-AS1 to form (Zn-Adenine)@Ab@lncRNA LEF1-AS1. Finally, the (Zn-Adenine)@Ab@lncRNA LEF1-AS1 NPs were locally injected into a rat model with collagen-induced arthritis (CIA). The arthritic injuries in each group were evaluated by HE staining and other methods. RESULTS: LEF1-AS1 was expressed at low levels in the primary RASFs. High expression levels of LEF1-AS1 were detected in the HFLS cells, which corresponded to a significant downregulation of miR-30-5p. In addition, the expression level of PIK3R2 was significantly increased, and that of p-PI3K and p-AKT were significantly downregulated in these cells. The (Zn-Adenine)@Ab@lncRNA LEF1-AS1 NPs significantly inhibited the proliferation of RASFs and decreased the production of inflammatory cytokines (IL-1ß, IL-6, TNF-α). Intra-articular injection (IAI) of (Zn-Adenine)@Ab@lncRNA LEF1-AS1 NPs significantly alleviated cartilage destruction and joint injury in the CIA-modeled rats. CONCLUSIONS: LEF1-AS1 interacts with miR-30-5p to inhibit the abnormal proliferation of RASFs by regulating the PI3K/AKT signal pathway. The (Zn-Adenine)@Ab NPs achieved targeted delivery of the loaded LEF1-AS1 into the RASFs, which improved the cellular internalization rate and therapeutic effects. Thus, LEF1-AS1 is a potential target for the treatment of RA.