OBJECTIVES: To explore the therapeutic mechanism of puerarin for alleviating synovitis in rats with collagen-induced arthritis (CIA). METHODS: In a SD rat model of CIA, we tested the effects of daily gavage of puerarin at low, moderate and high doses (10, 30, and 100 mg/kg, respectively) for 3 weeks, with tripterygium glycosides (GTW, 10 mg/kg) as the positive control, on swelling in the hind limb joints regions evaluated by arthritis index scoring. Mass fraction of the liver of the rats was calculated, and pathologies in joint synovial membrane were observed with HE staining. The expressions of transforming growth factor β‑activated kinase-1 (TAK1), Toll-like receptor 4 (TLR4), and nuclear factor kappa-Bp65 (NF‑κB p65) at the mRNA and protein levels in the synovial tissues were detected using Real-time PCR and Western blotting. RESULTS: Compared with those in the model group, the rats in GTW group and high-dose puerarin group showed significantly reduced mass fraction of the liver. Treatment with GTW and puerarin at the 3 doses all significantly alleviated plantar swelling, lowered arthritis index scores, and improved synovitis in CIA rats (P<0.05), and the effects of puerarin showed an obvious dose dependence. Both GTW and puerarin treatments significantly lowered TAK1, TLR4, and NF‑κB p65 mRNA and protein expressions in the synovium of CIA rats. CONCLUSIONS Puerarin alleviates synovium damages in CIA rats possibly by suppressing the TLR4/NF‑κB signaling pathway via downregulating TAK1 expression.
Animals ; Toll-Like Receptor 4/metabolism* ; Rats, Sprague-Dawley ; Rats ; MAP Kinase Kinase Kinases/metabolism* ; Signal Transduction/drug effects* ; Arthritis, Rheumatoid/drug therapy* ; NF-kappa B/metabolism* ; Isoflavones/therapeutic use* ; Male ; Arthritis, Experimental/drug therapy* ; Transcription Factor RelA/metabolism* ; Synovial Membrane/metabolism*

Andrographolide sulfonate (AS) is a sulfonated derivative of andrographolide extracted from Andrographis paniculata (Burm.f.) Nees, and has been approved for several decades in China. The present study aimed to investigate the novel therapeutic application and possible mechanisms of AS in the treatment of rheumatoid arthritis. Results indicated that administration of AS by injection or gavage significantly reduced the paw swelling, improved body weights, and attenuated pathological changes in joints of rats with adjuvant-induced arthritis. Additionally, the levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and IL-1β in the serum and ankle joints were reduced. Bioinformatics analysis, along with the spleen index and measurements of IL-17 and IL-10 levels, suggested a potential relationship between AS and Th17 cells under arthritic conditions. In vitro, AS was shown to block Th17 cell differentiation, as evidenced by the reduced percentages of CD4⁺ IL-17A⁺ T cells and decreased expression levels of RORγt, IL-17A, IL-17F, IL-21, and IL-22, without affecting the cell viability and apoptosis. This effect was attributed to the limited glycolysis, as indicated by metabolomics analysis, reduced glucose uptake, and pH measurements. Further investigation revealed that AS might bind to hexokinase2 (HK2) to down-regulate the protein levels of HK2 but not glyceraldehyde-3-phosphate dehydrogenase (GAPDH) or pyruvate kinase M2 (PKM2), and overexpression of HK2 reversed the inhibition of AS on Th17 cell differentiation. Furthermore, AS impaired the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signals in vivo and in vitro, which was abolished by the addition of lactate. In conclusion, AS significantly improved adjuvant-induced arthritis (AIA) in rats by inhibiting glycolysis-mediated activation of PI3K/AKT to restrain Th17 cell differentiation.
Animals ; Th17 Cells/immunology* ; Diterpenes/pharmacology* ; Arthritis, Rheumatoid/metabolism* ; Proto-Oncogene Proteins c-akt/immunology* ; Glycolysis/drug effects* ; Cell Differentiation/drug effects* ; Phosphatidylinositol 3-Kinases/genetics* ; Rats ; Male ; Rats, Sprague-Dawley ; Humans ; Andrographis paniculata/chemistry* ; Arthritis, Experimental/drug therapy* ; Interleukin-17/immunology* ; Signal Transduction/drug effects*

The present study investigated the mechanism of artesunate in the treatment of bone destruction in experimental rheumatoid arthritis(RA) based on transcriptomics and network pharmacology. The transcriptome sequencing data of artesunate in the inhibition of osteoclast differentiation were analyzed to obtain differentially expressed genes(DEGs). GraphPad Prism 8 software was used to plot volcano maps and heat maps were plotted through the website of bioinformatics. GeneCards and OMIM were used to collect information on key targets of bone destruction in RA. The DEGs of artesunate in inhibiting osteoclast differentiation and key target genes of bone destruction in RA were intersected by the Venny 2.1.0 platform, and the intersection target genes were analyzed by Gene Ontology(GO)/Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment. Finally, the receptor activator of nuclear factor-κB(RANKL)-induced osteoclast differentiation model and collagen-induced arthritis(CIA) model were established. Quantitative real time polymerase chain reaction(q-PCR), immunofluorescence, and immunohistochemistry were used to verify the pharmacological effect and molecular mechanism of artesunate in the treatment of bone destruction in RA. In this study, the RANKL-induced osteoclast differentiation model in vitro was established and intervened with artesunate, and transcriptome sequencing data were analyzed to obtain 744 DEGs of artesunate in inhibiting osteoclast differentiation. A total of 1 291 major target genes of bone destruction in RA were obtained from GeneCards and OMIM. The target genes of artesunate in inhibiting osteoclast differentiation and the target genes of bone destruction in RA were intersected to obtain 61 target genes of artesunate against bone destruction in RA. The intersected target genes were analyzed by GO/KEGG enrichment. According to the results previously reported, the cytokine-cytokine receptor interaction signaling pathway was selected for experimental verification. Artesunate intervention in the RANKL-induced osteoclast differentiation model showed that artesunate inhibited CC chemokine receptor 3(CCR3), CC chemokine receptor 1(CCR1) and leukemia inhibitory factor(LIF) mRNA expression in osteoclasts in a dose-dependent manner compared with the RANKL-induced group. Meanwhile, the results of immunofluorescence and immunohistochemistry showed that artesunate could dose-dependently reduce the expression of CCR3 in osteoclasts and joint tissues of the CIA rat model in vitro. This study indicated that artesunate regulated the CCR3 in the cytokine-cytokine receptor interaction signaling pathway in the treatment of bone destruction in RA and provided a new target gene for the treatment of bone destruction in RA.
Rats ; Animals ; Arthritis, Experimental/drug therapy* ; Artesunate/therapeutic use* ; Arthritis, Rheumatoid/genetics* ; Transcriptome ; Network Pharmacology ; Osteoclasts ; Receptors, Cytokine/therapeutic use*

Traditionally, Tripterygium hypoglaucum (Levl.) Hutch (THH) are widely used in Chinese folk to treat rheumatoid arthritis (RA). This study aimed to investigate whether the anti-RA effect of THH is related with the gut microbiota. The main components of prepared THH extract were identified by HPLC-MS. C57BL/6 mice with adjuvant-induced arthritis (AIA) were treated with THH extract by gavage for one month. THH extract significantly alleviated swollen ankle, joint cavity exudation, and articular cartilage destruction in AIA mice. The mRNA and protein levels of inflammatory mediators in muscles and plasma indicated that THH extract attenuated inflammatory responses in the joint by blocking TLR4/MyD88/MAPK signaling pathways. THH extract remarkably restored the dysbiosis of the gut microbiota in AIA mice, featuring the increases of Bifidobacterium, Akkermansia, and Lactobacillus and the decreases of Butyricimonas, Parabacteroides, and Anaeroplasma. Furthermore, the altered bacteria were closely correlated with physiological indices and drove metabolic changes of the intestinal microbiota. In addition, antibiotic-induced pseudo germ-free mice were employed to verify the role of the intestinal flora. Strikingly, THH treatment failed to ameliorate the arthritis symptoms and signaling pathways in pseudo germ-free mice, which validates the indispensable role of the intestinal flora. For the first time, we demonstrated that THH extract protects joint inflammation by manipulating the intestinal flora and regulating the TLR4/MyD88/MAPK signaling pathway. Therefore, THH extract may serve as a microbial modulator to recover RA in clincial practice.ver RA in clincial practice.
Mice ; Animals ; Gastrointestinal Microbiome ; Tripterygium ; Myeloid Differentiation Factor 88/genetics* ; Toll-Like Receptor 4/genetics* ; Mice, Inbred C57BL ; Arthritis, Experimental/drug therapy*

This study aims to investigate the therapeutic effect of alcohol extract of root and root bark of Toddalia asiatica(TAAE) on collagen-induced arthritis(CIA) in rats through phosphatidylinoinosidine-3 kinase/protein kinase B(PI3K/Akt) signaling pathway. To be specific, CIA was induced in rats, and then the rats were treated(oral, daily) with TAAE and Tripterygium Glycoside Tablets(TGT), respectively. The swelling degree of the hind leg joints was scored weekly. After 35 days of administration, the histopathological changes were observed based on hematoxylin and eosin(HE) staining. Enzyme-linked immunosorbent assay(ELISA) was employed to detect the levels of cytokines [tumor necrosis factor-α(TNF-α), interleukin(IL)-6)]. Terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL) staining was performed to detect the apoptosis of synoviocytes in rats. Western blot was used to detect the expression levels of apoptosis-related proteins B-cell lymphoma 2(Bcl-2)-associated X(Bax), Bcl-2, and caspase-3 and pathway-related proteins phosphoinositide 3-kinase(PI3K), phosphorylated(p)-PI3K, protein kinase B(Akt), and p-Akt. RT-qPCR was conducted to examine the mRNA levels of Bax, Bcl-2, caspase-3, TNF-α, IL-6, and IL-1β and pathway-related proteins PI3K, p-PI3K, Akt, and p-Akt. TAAE can alleviate the joint swelling in CIA rats, reduce serum levels of inflammatory cytokines, improve synovial histopathological changes, promote apoptosis of synoviocytes, and inhibit synovial inflammation. In addition, RT-qPCR and Western blot results showed that TAAE up-regulated the level of Bax, down-regulated the level of Bcl-2, and activated caspase-3 to promote apoptosis in synoviocytes. TAAE effectively down-regulated the protein levels of p-PI3K and p-Akt. In this study, TAAE shows therapeutic effect on CIA in rats and reduces the inflammation. The mechanism is that it suppresses PI3K/Akt signaling pathway and promotes synoviocyte apoptosis. Overall, this study provides a new clue for the research on the anti-inflammatory mechanism of TAAE and lays a theoretical basis for the better clinical application of TAAE in the treatment of inflammatory and autoimmune diseases.
Rats ; Animals ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Caspase 3/genetics* ; Tumor Necrosis Factor-alpha/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Plant Bark ; Anti-Inflammatory Agents/therapeutic use* ; Arthritis, Experimental/chemically induced* ; Inflammation/drug therapy* ; Cytokines/metabolism* ; Proto-Oncogene Proteins c-bcl-2 ; Apoptosis

A fluorescence endoscopic laser confocal microscope(FELCM) was used to direct the injection of sinomenine solid lipid nanoparticles(Sin-SLN) into the joint, and the in vitro effectiveness of Sin-SLN in the treatment of rheumatoid arthritis(RA) was evaluated. Sin-SLN was prepared with the emulsion evaporation-low temperature curing method. The Sin-SLN prepared under the optimal conditions showed the encapsulation efficiency of 64.79%±3.12%, the drug loading of 3.84%±0.28%, the average particle size of(215.27±4.21) nm, and the Zeta potential of(-32.67±0.84) mV. Moreover, the Sin-SLN demonstrated good stability after sto-rage for 30 days. The rabbit model of RA was established by the subcutaneous injection of ovalbumin and complete Freund's adjuvant. Five groups were designed, including a control group, a model group, a Sin(1.5 mg·kg~(-1)) group, a Sin-SLN(1.5 mg·kg~(-1)) group, and a dexamethasone(positive drug, 1.0 mg·kg~(-1), ig) group. The control group and the model group only received puncture treatment without drug injection. After drug administration, the local skin temperature and knee joint diameter were monitored every day. The knee joint diameter and the local skin temperature were lower in the drug administration groups than in the model group(P<0.05, P<0.01). FELCM recorded the morphological alterations of the cartilage of knee joint. The Sin-SLN group showed compact tissue structure and smooth surface of the cartilage. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the serum le-vels of interleukin-1(IL-1) and tumor necrosis factor-α(TNF-α). The findings revealed that the Sin-SLN group had lower IL-1 and TNF-α levels than the model group(P<0.05, P<0.01). Hematoxylin-eosin(HE) staining was employed to reveal the pathological changes of the synovial tissue, which were significantly mitigated in the Sin-SLN group. The prepared Sin-SLN had uniform particle size and high stability. Through joint injection administration, a drug reservoir was formed. Sin-SLN effectively alleviate joint swelling and cartilage damage of rabbit, down-regulated the expression of inflammatory cytokines, and inhibited the epithelial proliferation and inflammatory cell infiltration of the synovial tissue, demonstrating the efficacy in treating RA.
Animals ; Rabbits ; Tumor Necrosis Factor-alpha ; Fluorescence ; Arthritis, Rheumatoid/drug therapy* ; Interleukin-1 ; Arthritis, Experimental/drug therapy*

The present study investigated the pharmacodynamic material basis of Laportea bulbifera in the treatment of rheumatoid arthritis. Firstly, human rheumatoid arthritis fibroblast-like synoviocyte line MH7A was cultured in vitro and treated with tumor necrosis factor alpha(TNF-α, 50 ng·mL~(-1)). The proliferation and the levels of inflammatory cytokines such as prostaglandin E2(PGE2), interleukin-1β(IL-1β), and interleukin-6(IL-6) of the MH7A cells exposed to the serum containing L. bulbifera were determined to evaluate the anti-rheumatoid arthritis effects of the serum. Furthermore, the ultra-performance liquid chromatography tandem mass spectrometry fingerprints of the L. bulbifera crude extract, the drug-containing serum, and the drug-free serum were compared to identify the compounds newly generated in the serum after oral administration of the extract. According to the peak areas of common peaks and the results of anti-rheumatoid arthritis effect test, the active components were identified. The serum containing L. bulbifera significantly inhibited the proliferation of the MH7A cells activated by TNF-α and the expression of PGE2, IL-6, and IL-1β. Thirty newly generated compounds were detected in the drug-containing serum. Among them, neochlorogenic acid, cryptochlorogenic acid, chlorogenic acid, rutin, isoquercitrin, luteoloside, kaempferol-3-O-rutinoside, and quercitrin were also present in the crude extract. Twelve characteristic peaks(3, 7, 8, 14, 18, 19, 21, 23, 24, m6, m7, and m15) were significantly correlated with the pharmaceutical effect. According to the correlations, neochlorogenic acid, cryptochlorogenic acid, and chlorogenic acid had great contributions to the anti-rheumatoid arthritis activity. This study preliminarily clarified the potential pharmacodynamic substances of L. bulbifera in the treatment of rheumatoid arthritis, which laid a theoretical and experimental foundation for further development and application of the medicinal plant.
Animals ; Arthritis, Experimental/drug therapy* ; Arthritis, Rheumatoid/drug therapy* ; Chlorogenic Acid/analogs & derivatives* ; Cytokines/metabolism* ; Dinoprostone ; Humans ; Interleukin-1beta/genetics* ; Interleukin-6 ; Plant Extracts/therapeutic use* ; Quinic Acid/analogs & derivatives* ; Rutin ; Tumor Necrosis Factor-alpha/metabolism* ; Urticaceae/chemistry*

This paper aims to explore the activity of Codonopsis canescens extract against rheumatoid arthritis(RA) based on the Toll-like receptors(TLRs)/mitogen-activated protein kinases(MAPKs)/nuclear factor kappa B(NF-κB) signaling pathways and its mechanism. The ultra-performance liquid chromatography-quadrupole time-of-flight/mass spectrometry(UPLC-Q-TOF-MS) was used to identify the components of C. canescens extract. Forty-eight male SD rats were randomly divided into six groups, namely the normal group, the model group, the methotrexate(MTX) tablet group, and the low, medium, and high-dose C. canescens extract(ZDS-L, ZDS-M, and ZDS-H) groups, with 8 rats in each group. The model of collagen-induced arthritis in rats was induced by injection of bovine type Ⅱ collagen emulsion. MTX(2.5 mg·kg~(-1)), ZDS-L, ZDS-M, and ZDS-H(0.3 g·kg~(-1), 0.6 g·kg~(-1), and 1.2 g·kg~(-1)) were administrated by gavage. Rats in the normal group and the model group received distilled water. MTX was given once every three days for 28 days, and the rest medicines were given once daily for 28 days. Body weight, degree of foot swelling, arthritis index, immune organ index, synovial histopathological changes, and serum levels of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), and interleukin-6(IL-6) were observed. Protein expressions of TLR2, TLR4, NF-κB p65, p38 MAPK, and p-p38 MAPK in rats were determined by Western blot. Thirty-four main components were identified by UPLC-Q-TOF-MS, including 15 flavonoids, 7 phenylpropanoids, 4 terpenoids, 4 organic acids, 2 esters, and 2 polyalkynes. As compared with the normal group, the body weight of the model group was significantly decreased(P<0.01), and foot swelling(P<0.05, P<0.01), arthritis index(P<0.01), and the immune organ index(P<0.01) were significantly increased. The synovial histopathological injury was obviously observed in the model group. The serum levels of inflammatory factors TNF-α, IL-1β, and IL-6 were significantly increased(P<0.01), and the protein expression levels of TLR2, TLR4, NF-κB p65, p-p38 MAPK/p38 MAPK in the synovial tissue were significantly increased(P<0.01) in the model group. As compared with the model group, the body weights of the ZDS dose groups were increased(P<0.01), and the degree of foot swelling(P<0.01) and the arthritis index were decreased(P<0.05, P<0.01). The immune organ index was decreased(P<0.01) in the ZDS dose groups, and the synovial tissue hyperplasia and inflammatory cell infiltration were alleviated. The serum levels of TNF-α, IL-1β, and IL-6 were significantly decreased(P<0.05, P<0.01), and the protein expression levels of TLR2, TLR4, NF-κB p65, p-p38 MAPK/p38 MAPK were decreased(P<0.05, P<0.01) in the ZDS dose groups. C. canescens extract containing apigenin, tricin, chlorogenic acid, aesculin, ferulic acid, caffeic acid, and oleanolic acid has a good anti-RA effect, and the mechanism may be related to the inhibition of TLRs/MAPKs/NF-κB signaling pathways.
Animals ; Cattle ; Male ; Rats ; Arthritis, Experimental/drug therapy* ; Arthritis, Rheumatoid/drug therapy* ; Body Weight ; Codonopsis/chemistry* ; Interleukin-6/blood* ; NF-kappa B/genetics* ; p38 Mitogen-Activated Protein Kinases/metabolism* ; Plant Extracts/therapeutic use* ; Rats, Sprague-Dawley ; Signal Transduction ; Toll-Like Receptor 2/metabolism* ; Toll-Like Receptor 4/metabolism* ; Tumor Necrosis Factor-alpha/pharmacology*

The ethyl acetate fraction of ethanol extract of Eucommiae Cortex can effectively inhibit joint inflammation and bone destruction in rats with collagen-induced arthritis(CIA) and has a potential therapeutic effect on rheumatoid arthritis. The triterpenoid(EU-Tid) and iridoid(EU-Idd) of Eucommiae Cortex are derivatives isolated from the ethyl acetate fraction of the ethanol extract of Eucommiae Cortex, and it is not clear whether they have inhibitory effects on joint inflammation and bone erosion in CIA rats. Therefore, based on the CIA model, the effects of EU-Tid, EU-Idd, and their combination(EU-TP) on arthritis in rats were observed, and the material basis of Eucommiae Cortex against arthritis was further clarified. The samples were collected two and four weeks after administration to observe the pathological changes in different stages of arthritis in CIA rats. For the rats in the model control group, with the prolongation of the disease course, the paw volume and arthritis score increased and histopathological lesions aggravated. Compared with the model control group, the drug administration groups showed reduced paw volumes and arthritis scores, and improved joint lesions and cartilage destruction. Additionally, the mRNA expression levels of tumor necrosis factor-α(TNF-α), interleukin-17(IL-17), and interleukin-23(IL-23) in the spleen were down-regulated in the drug administration groups. EU-TP and EU-Tid at concentrations of 160 and 320 μg·mL~(-1) could significantly inhibit the proliferation of human fibroblast-like synoviocytes-RA(HFLS-RA) and nitric oxide(NO) release in the supernatant of RAW264.7 cells induced by lipopolysaccharide(LPS) at the concentration range of 10-80 μg·mL~(-1) in vitro. EU-Idd had no effect on the proliferation of HFLS-RA but could reduce the NO release at concentrations of 40 and 80 μg·mL~(-1). The results indicated that the terpenoids of Eucommiae Cortex had great potential in the treatment of rheumatoid arthritis.
Rats ; Humans ; Animals ; Arthritis, Experimental/drug therapy* ; Iridoids/pharmacology* ; Triterpenes/therapeutic use* ; Arthritis, Rheumatoid/drug therapy* ; Tumor Necrosis Factor-alpha ; Plant Extracts/pharmacology* ; Inflammation/drug therapy* ; Ethanol ; Cytokines

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease. It is known that aucubin (AU) exerts anti-inflammatory activity, but its effects and mechanisms in RA are unclear. This study investigated the anti-inflammatory effects and mechanisms of AU in vivo and in vitro. Human fibroblast-like synoviocyte cells from patients with RA (HFLS-RA), RAW264.7 cells, and MC3T3-E1 cells were used to evaluate the effects of AU on migration, invasion, apoptosis, osteoclast differentiation and production. Immunofluorescence was used to observe nuclear translocation of nuclear factor (NF)-κB, the double luciferase reporter gene method was used to observe NF-κB-p65 activity in AU-treated MC3T3-E1 cells. RT-qPCR was used to measure expression of bone metabolism and inflammation-related genes, and western blot was used to measure bone metabolism and NF-κB protein expression levels. Collagen-induced arthritis (CIA) rat model was used for pharmacodynamics study. Arthritis indexes were measured in the ankle and knee, histological staining and Micro-computed tomography were performed on the ankle joints. Also, inflammatory factor gene expression and the levels of NF-κB-related proteins were detected as in vitro. AU effectively inhibited HFLS-RA cell migration and invasion, promoted apoptosis, and inhibited RAW264.7 cell differentiation into osteoclasts, as well as inhibited NF-κB-p65 activity in MC3T3-E1 cells. Notably, AU significantly reduced the gene expression levels of three cell-related inflammatory factors and bone metabolism factors, effectively inhibited the expression of p-Iκκα β, p-IκBα, and p-p65 proteins. In vivo, AU relieved joint inflammation, reduced related inflammatory factors, and inhibited NF-κB signaling. It could be used to treat RA-related synovial inflammation and bone destruction through the NF-κB pathway.
Animals ; Anti-Inflammatory Agents/therapeutic use* ; Arthritis, Experimental ; Arthritis, Rheumatoid/drug therapy* ; Cells, Cultured ; Humans ; Inflammation/pathology* ; Iridoid Glucosides ; NF-kappa B/metabolism* ; Rats ; X-Ray Microtomography