Dehydroevodiamine suppresses inflammatory responses in adjuvant-induced arthritis rats and human fibroblast-like synoviocytes.

Dehydroevodiamine (DHE) is an effective natural active substance extracted from Euodiae Fructus, which is a widely used herbal drug in traditional Chinese medicine. The focus of this study was to test the possibility of using DHE in the treatment of rheumatoid arthritis (RA) diseases. A rat model of adjuvant-induced arthritis (AIA) was generated using Complete Freund's Adjuvant (CFA). Body weight changes, arthritis scores, ankle pathology, tumor necrosis factor-alpha (TNF-α), interleukin-1ß(IL-1ß), interleukin-6 (IL-6), and interleukin-17 (IL-17) secretion, as well as matrix metalloproteinase (MMP) expression in joint tissue, were measured as indicators of viability of DHE medicated AIA rats. Human fibroblast-like synoviocytes (MH7A cells) were connected to check these impacts. The results confirmed that DHE administration had an excellent therapeutic impact on the AIA rat model, substantially relieving joint swelling, inhibiting synovial pannus hyperplasia, and decreasing joint scores. In addition, the serum enzyme-linked immunosorbent assay (ELISA) showed that DHE treatment reduced the expression of pro-inflammatory factors in AIA rats. The immunohistochemical results showed that DHE treatment could reduce the synthesis of MMPs such as matrix metalloproteinase-1(MMP-1) and matrix metalloproteinase-3 (MMP-3) in the ankle tissue of AIA rats. In vitro, DHE inhibited cell proliferation, mRNA transcription, protein synthesis of proinflammatory factors such as IL-1ßand IL-6, and matrix metalloproteinases such as MMP-1 and MMP-3. Furthermore, DHE inhibited the phosphorylation levels of p38, JNK, and ERK proteins in TNF-α-treated MH7A cells.This work assessed the effect of DHE in AIA rats and revealed its mechanism in vitro.

Phospholipase A1 Member A Activates Fibroblast-like Synoviocytes through the Autotaxin-Lysophosphatidic Acid Receptor Axis.

Lysophosphatidylserine (lysoPS) is known to regulate immune cell functions. Phospholipase A1 member A (PLA1A) can generate this bioactive lipid through hydrolysis of sn-1 fatty acids on phosphatidylserine (PS). PLA1A has been associated with cancer metastasis, asthma, as well as acute coronary syndrome. However, the functions of PLA1A in the development of systemic autoimmune rheumatic diseases remain elusive. To investigate the possible implication of PLA1A during rheumatic diseases, we monitored PLA1A in synovial fluids from patients with rheumatoid arthritis and plasma of early-diagnosed arthritis (EA) patients and clinically stable systemic lupus erythematosus (SLE) patients. We used human primary fibroblast-like synoviocytes (FLSs) to evaluate the PLA1A-induced biological responses. Our results highlighted that the plasma concentrations of PLA1A in EA and SLE patients were elevated compared to healthy donors. High concentrations of PLA1A were also detected in synovial fluids from rheumatoid arthritis patients compared to those from osteoarthritis (OA) and gout patients. The origin of PLA1A in FLSs and the arthritic joints remained unknown, as healthy human primary FLSs does not express the PLA1A transcript. Besides, the addition of recombinant PLA1A stimulated cultured human primary FLSs to secrete IL-8. Preincubation with heparin, autotaxin (ATX) inhibitor HA130 or lysophosphatidic acid (LPA) receptor antagonist Ki16425 reduced PLA1A-induced-secretion of IL-8. Our data suggested that FLS-associated PLA1A cleaves membrane-exposed PS into lysoPS, which is subsequently converted to LPA by ATX. Since primary FLSs do not express any lysoPS receptors, the data suggested PLA1A-mediated pro-inflammatory responses through the ATX-LPA receptor signaling axis.

Nitidine chloride inhibits fibroblast like synoviocytes-mediated rheumatoid synovial inflammation and joint destruction by targeting KCNH1.

OBJECTIVE: Nitidine chloride (NC), a natural small molecular compound from traditional Chinese herbal medicine zanthoxylum nitidum, has been shown to exhibit anti-tumor effect. However, its role in autoimmune diseases such as rheumatoid arthritis (RA) is unknown. Here, we investigate the effect of NC in controlling fibroblast-like synoviocytes (FLS)-mediated synovial inflammation and joint destruction in RA and further explore its underlying mechanism(s). METHODS: FLSs were separated from synovial tissues obtained from patients with RA. Protein expression was analyzed by Western blot or immunohistochemistry. Gene expression was measured using quantitative RT-PCR. ELISA was used to measure the levels of cytokines and MMPs. Cell proliferation was detected using EdU incorporation. Migration and invasion were evaluated by Boyden chamber assay. RNA sequencing analysis was used to identify the target of NC. Collagen-induced arthritis (CIA) model was used to evaluate the in vivo effect of NC. RESULTS: NC treatment reduced the proliferation, migration, invasion, and lamellipodia formation but not apoptosis of RA FLSs. We also demonstrated the inhibitory effect of NC on TNF-α-induced expression and secretion of IL-6, IL-8, CCL-2, MMP-1 and MMP-13. Furthermore, we identified KCNH1, a gene that encodes ether-à-go-go-1 channel, as a novel targeting gene of NC in RA FLSs. KCNH1 expression was increased in FLSs and synovial tissues from patients with RA compared to healthy controls. KCNH1 knockdown or NC treatment decreased the TNF-α-induced phosphorylation of AKT. Interestingly, NC treatment ameliorated the severity of arthritis and reduced synovial KCNH1 expression in mice with CIA. CONCLUSIONS: Our data demonstrate that NC treatment inhibits aggressive and inflammatory actions of RA FLSs by targeting KCNH1 and sequential inhibition of AKT phosphorylation. Our findings suggest that NC might control FLS-mediated rheumatoid synovial inflammation and joint destruction, and be a novel therapeutic agent for RA.

Efficacy of Xixiancao (Herba Siegesbeckiae Orientalis) on interactions between nuclear factor kappa-B and inflammatory cytokines in inflammatory reactions of rat synovial cells induced by sodium urate.

OBJECTIVE: To investigate the interaction between nuclear factor kappa-B (NF-κB) and inflammatory cytokines in synovial cell inflammatory responses induced by sodium urate, and to evaluate the efficacy of Xixiancao (Herba Siegesbeckiae Orientalis) on these interactions. METHODS: The interactions between NF-κB and inflammatory cytokines/mediators in synovial cells in acute gouty arthritis were investigated. We observed the expressions of NF-κB, interleukin (IL)-1ß, IL-8, and tumor necrosis factor alpha (TNF-α) in synovial cells at different timepoints in an in vitro model of synovial cell inflammatory responses induced by sodium urate and in an in vivo model of gouty arthritis. Changes in the expressions of NF-κB, IL-1ß, IL-8, and TNF- in synovial cells of all experimental groups were compared and observed after treatment with different doses of Xixiancao (Herba Siegesbeckiae Orientalis) and colchicine. The interactions between NF-κB and IL-1ß, IL-8, and TNF-α were analyzed. Pathological changes in synovial tissues were observed in rats with acute gouty arthritis. RESULTS: Compared with the blank group, the expression levels of NF-κB, IL-1ß, IL-8, and TNF-α were increased significantly at different timepoints in the in vitro model of synovial cell inflammatory responses induced by sodium urate, and in the in vivo model of gouty arthritis. Compared with the model group, the expressions of NF-κB, IL-1ß, IL-8, and TNF-α in synovial cells induced by sodium urate were decreased in the different Xixiancao (Herba Siegesbeckiae Orientalis) dose groups and the colchicine group. The effect was more obvious in the high dose Xixiancao (Herba Siegesbeckiae Orientalis) group. The expression of NF-κB in synovial cells was positively correlated with the expressions of IL-1ß, IL-8, and TNF-. Histopathological examination of synovial tissues in the high dose Xixiancao (Herba Siegesbeckiae Orientalis) group and Colchicine group showed that the characteristics of acute gouty arthritis were reduced, and there was a trend towards a positive correlation between NF-κB and inflammatory cytokine expressions. CONCLUSION: The activation of NF-κB is associated with the activation of IL-1ß, IL-8, and TNF-α during the pathogenesis of acute gouty arthritis, leading to the continuation and enhancement of the inflammatory response. Expressions of IL-1ß, IL-8, and TNF-α in synoviocytes during acute gouty arthritis effectively inhibit local inflammation.

Evaluation of Anti-inflammatory Effects of Choerospondias axillaris Fruit's Methanolic Extract in Synoviocytes and CIA Rat Model.

BACKGROUND: Rheumatoid Arthritis (RA) is an autoimmune, systemic disease mainly affecting joints. Presently, there is no specific treatment/ drug available for curing RA except few supportive medicines. Therefore, the focus has been shifted to medicinal plants for the treatment of such diseases. Choerospondias axillaris commonly known as Lupsi/Lapsi and has been reported to have several properties for the treatment of various diseases. OBJECTIVE: The present study has been conducted to explore the anti-inflammatory effects of Choerospondias axillaris fruit extract on Synoviocytes (FLS) and Collagen-Induced Arthritis (CIA) rat model. METHODS: Methanolic extract of the Choerospondias axillaris fruit was used for determining phytochemical, antioxidant and anti-inflammatory properties. Antioxidant activity of Choerospondias axillaris fruit was determined by free radicals scavenging assays and bioactive compounds were identified via LC-MS/MS analysis. Anti-inflammatory effect was investigated in RA and Osteo Arthritis (OA) primary cells and also in Collagen Induced Arthritis (CIA) rat models. Further, the medicinal properties of anti-inflammatory bioactive compounds were supported by docking studies. RESULTS: In-vitro and in-vivo studies showed significant decrease in the levels of inflammatory cytokines. Docking analysis revealed that quercetin inhibits TNF-α having -9.1 kcal/mol binding energy and 10.13 µM inhibitory constant. Quercetin also inhibits IL-6 having -6.6 kcal/mol binding energy and 21.9 µM inhibitory constant. CONCLUSION: Observed results suggest that the underutilized fruit Choerospondias axillaris can be used to reduce the inflammation of inflammatory diseases like RA.

(5R)-5-Hydroxytriptolide (LLDT-8) induces substantial epigenetic mediated immune response network changes in fibroblast-like synoviocytes from rheumatoid arthritis patients.

Tripterygium is a traditional Chinese medicine that has widely been used in the treatment of rheumatic disease. (5R)-5-hydroxytriptolide (LLDT-8) is an extracted compound from Tripterygium, which has been shown to have lower cytotoxicity and relatively higher immunosuppressive activity when compared to Tripterygium. However, our understanding of LLDT-8-induced epigenomic impact and overall regulatory changes in key cell types remains limited. Doing so will provide critically important mechanistic information about how LLDT-8 wields its immunosuppressive activity. The purpose of this study was to assess the effects of LLDT-8 on transcriptome including mRNAs and long non-coding RNA (lncRNAs) in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) by a custom genome-wide microarray assay. Significant differential expressed genes were validated by QPCR. Our work shows that 394 genes (281 down- and 113 up-regulated) were significantly differentially expressed in FLS responding to the treatment of LLDT-8. KEGG pathway analysis showed 20 pathways were significantly enriched and the most significantly enriched pathways were relevant to Immune reaction, including cytokine-cytokine receptor interaction (P = 4.61 × 10-13), chemokine signaling pathway (P = 1.01 × 10-5) and TNF signaling pathway (P = 2.79 × 10-4). Furthermore, we identified 618 highly negatively correlated lncRNA-mRNA pairs from the selected significantly differential lncRNA and mRNA including 27 cis-regulated and 591 trans-regulated lncRNA-mRNAs modules. KEGG and GO based function analysis to differential lncRNA also shown the enrichment of immune response. Finally, lncRNA-transcription factor (TF) and lncRNA-TF-mRNA co-expression network were constructed with high specific network characteristics, indicating LLDT-8 would influence the expression network within the whole FLS cells. The results indicated that the LLDT-8 would mainly influence the FLS cells systemically and specially in the process of immune related pathways.

Physcion 8­O­ß­glucopyranoside extracted from Polygonum cuspidatum exhibits anti­proliferative and anti­inflammatory effects on MH7A rheumatoid arthritis­derived fibroblast­like synoviocytes through the TGF­ß/MAPK pathway.

The present study aimed to investigate the anti­arthritic effect of physcion 8­O­ß­glucopyranoside (POGD) and its possible mechanisms. The anti­proliferative effects of POGD on MH7A cells were detected using a CCK­8 assay, and the release of pro­inflammatory cytokines, interleukin (IL)­1ß, IL­6, IL­8, IL­12 and IL­17A, were determined by ELISA. A type II collagen­induced arthritis (CIA) rat model was established to evaluate the anti­arthritic effect of POGD in vivo. The paw volumes, arthritis indices and serum levels of tumor necrosis factor (TNF)­α, IL­1ß, IL­6, IL­8, IL­17A were determined by ELISA. The mRNA expression levels of matrix metalloproteinase (MMP)­2, MMP­3, MMP­9, vascular endothelial growth factor and cyclooxygenase­2 were determined by reverse transcription­quantitative polymerase chain reaction analysis, and the expression levels of transforming growth factor (TGF)­ß1, small mothers against decapentaplegic (Smad)4, Smad7, c­Jun N­terminal kinase (JNK), phosphorylated (p­)JNK, p­P38, P38, p­extracellular signal­regulated kinase (ERK)1/2, ERK1/2, nuclear factor (NF)­κB p65 in the nucleus (N), cytosolic NF­κB p65 (C), and inhibitor of NF­κB (IκB) were determined by western blot analysis. The results indicated that POGD significantly inhibited MH7A cell growth. POGD markedly inhibited paw swelling and the arthritis indices of the CIA rats, and POGD may also inhibit the release of pro­inflammatory cytokines. Furthermore, POGD downregulated the expression levels of TGF­ß1, Smad4, NF­κB p65 (N), p38, p­p38, p­ERK1/2, JNK, p­JNK, TGF­ß1, Smad4, p­JNK, JNK, p­P38, P38, p­ERK1/2, ERK1/2 and NF­κB p65 (N), and upregulated the Smad7, NF­κB p65 (C) and IκB in TNF­α induced MH7A cells. In conclusion, the results suggested that POGD is a promising potential anti­inflammatory drug, and that POGD may decrease the expression of pro­inflammatory cytokines and mediators via inhibiting the TGF­ß/NF­κB/mitogen­activated protein kinase pathways.

Sinomenine inhibits fibroblast-like synoviocyte proliferation by regulating α7nAChR expression via ERK/Egr-1 pathway.

Fibroblast like synoviocyte (FLS) is a crucial in the pathogenesis of rheumatoid arthritis (RA), and involved in inflammation and joint destruction. Sinomenine (SIN), an alkaloid derived from the plant Sinomenium acutum, has anti-inflammatory and analgesic effect and been used for RA treatment in China. Alpha 7 nicotinic acetylcholine receptors (α7nAChR), as the key receptor in cholinergic anti-inflammatory pathway (CAP) to inhibit inflammation, has been detected in RA patients synovium, but its role is still unclear. Here we investigated the association between the aggressive proliferation of FLS and α7nAChR expression and the effect of sinomenine. FLS was isolated from synovial tissues of adjuvant-induced-arthritis (AIA) rat. Tumor necrosis factor(TNF)-α was used to induce the aggressive proliferation of FLS. MTT assay was applied to evaluate the proliferation of FLS. The messenger RNA (mRNA) and protein levels of α7nAChR and early growth response gene-1 (Egr-1) were measured. The results showed that TNF-α induced FLS proliferation in vitro (P < .01) and increased the phosphorylation of ERK1/2 and the expression of Egr-1 and α7nAChR (P < .05 or P < .01). U0126, the inhibitor of ERK1/2 inhibited α7nAChR expression and FLS proliferation significantly (P < .05 or P < .01). Specific short interference RNA(siRNA) of α7nAChR decreased α7nAChR expression and inhibited FLS proliferation as well. SIN inhibited the proliferation of FLS and decreased the phosphorylation of ERK1/2, and the expression of Egr-1 and α7nAChR induced by TNF-α (P < .05). In conclusion, the expression of α7nAChR involved in the aggressive proliferation of FLS induced by TNF-α and was regulated by ERK/Egr-1 signal pathway. SIN inhibited FLS proliferation and α7nAChR expression through inhibiting ERK/Egr-1 signal pathway, this may contribute to the anti-inflammatory and anti-arthritic effect of SIN.

Therapeutic effect of Cryptotanshinone on experimental rheumatoid arthritis through downregulating p300 mediated-STAT3 acetylation.

BACKGROUND AND PURPOSE: The balance between T helper 17 (Th17) cells and regulatory T (Treg) cells, plays a critical role in rheumatoid arthritis (RA). The differentiation of Th17 cells requires the activation of STAT3, which determines the balance of Th17/Treg. Here, we investigated the therapeutic effect of Cryptotanshinone (CTS) on collagen induced mouse arthritis and explored the underlying mechanisms. EXPERIMENTAL APPROACH: Arthritis was induced in DBA/1 mice with bovine collagen type II and complete Freund's adjuvant. CTS was given at 20mgkg-1d-1 or 60mgkg-1d-1 by gavage for 6weeks. The immuno-inflammation and joint destruction were evaluated and the balance of Th17/Treg was determined. STAT3 acetylation and phosphorylation were detected by western blotting, and the involvement of p300 was investigated by siRNA and plasmid overexpression. KEY RESULTS: CTS at a dose of 60mgkg-1d-1 ameliorated the inflammation and joint destruction in CIA mice. It improved Th17/Treg imbalance, and inhibited both acetylation and phosphorylation of STAT3. CTS reduced p300 expression and its binding to STAT3, but increased phosphorylated AMPK. Knockdown of p300 mimicked the inhibitory effect of CTS on STAT3 acetylation and phosphorylation, which could be partially rescued by overexpression of p300-WT, but not p300-dominant negative (DN) construct. CONCLUSION AND IMPLICATIONS: Our study suggested that the anti-arthritis effects of CTS were attained through suppression of p300-mediated STAT3 acetylation. Our data suggest that CTS might be a potential immune modulator for RA treatment.

p53 predominantly regulates IL-6 production and suppresses synovial inflammation in fibroblast-like synoviocytes and adjuvant-induced arthritis.

BACKGROUND: Dominant-negative somatic mutations of p53 has been identified in the synovium of patients with rheumatoid arthritis (RA), in which interleukin (IL)-6 has been established as a pivotal inflammatory cytokine. The aim of this study was to clarify the significance of p53 in the longstanding inflammation in RA by modulating IL-6. METHODS: We established adjuvant-induced arthritis (AIA) in Lewis rats and treated them with p53 activator, and then analyzed the histopathology of the synovium and IL-6 expression. Human fibroblast-like synoviocytes (FLS) were cultured and transfected with p53-siRNA or transduced with adenovirus (Ad)-p53, and then assessed with MTT, TUNEL staining, and luciferase assay. IL-1ß, tumor necrosis factor (TNF)-α and IL-17 were used to stimulate FLS, and subsequent IL-6 expression as well as relevant signal pathways were explored. RESULTS: p53 significantly reduced synovitis as well as the IL-6 level in the AIA rats. It controlled cell cycle arrest and proliferation, but not apoptosis. Proinflammatory cytokines inhibited p53 expression in FLS, while p53 significantly suppressed the production of IL-6. Furthermore, IL-6 expression in p53-deficient FLS was profoundly reduced by NF-kappaB, p38, JNK, and ERK inhibitors. CONCLUSION: Our findings reveal a novel function of p53 in controlling inflammatory responses and suggest that p53 abnormalities in RA could sustain and accelerate synovial inflammation mainly through IL-6. p53 may be a key modulator of IL-6 in the synovium and plays a pivotal role in suppressing inflammation by interaction with the signal pathways in RA-FLS. Interfering with the p53 pathway could therefore be an effective strategy to treat RA.

Majoon ushba, a polyherbal compound, suppresses pro-inflammatory mediators and RANKL expression via modulating NFкB and MAPKs signaling pathways in fibroblast-like synoviocytes from adjuvant-induced arthritic rats.

Fibroblast-like synoviocytes (FLS) are inhabitant mesenchymal cells of synovial joints and have been recognized to play an imperative role in the immunopathogenesis of rheumatoid arthritis (RA). Blocking these pathological roles of FLS provides a potentially important therapeutic strategy for the treatment for RA. A recent study had confirmed that majoon ushba (MU), a polyherbal unani compound, possesses anti-arthritic effects in in vivo. Toward this direction, an effort has been made to understand the effect of MU on FLS derived from adjuvant-induced arthritis (AIA) rats. Here, we observed that MU administration (100-300 µg/ml) significantly inhibited the expression and phosphorylation of NFкB-p65 protein similar to that of the Bay 11-7082 (NFкB inhibitor) in NFкB signaling pathway and suppressed the protein expression of ERK1/2 and JNK1/2 in MAPKs signaling pathway in AIA-FLS. In addition, the protein expression of TNF-α, IL-17, RANKL, and iNOS was also found reduced. MU treatment significantly inhibited the mRNA expression of pro-inflammatory mediators (TNF-α, IL-1ß, IL-6, MCP-1, IL-17, iNOS, and COX-2), transcription factors (NFкB-p65 and AP-1), and RANKL and attenuated the overproduction of TNF-α, IL-1ß, IL-6, and MCP-1 (ELISA) in AIA-FLS. Furthermore, MU treatment significantly inhibited the level of lipid peroxidation, lysosomal enzymes release, and glycoproteins and increased antioxidant status (superoxide dismutase and catalase) in AIA-FLS. In conclusion, the results of this study provide evidence that MU possesses anti-inflammatory effect against AIA-FLS through the decrease in pro-inflammatory mediators expression by suppressing NFкB and MAPKs signaling pathways.