bay-11-7082 and Arthritis--Rheumatoid

To investigate the effect of gentiopicrin on the expressions of inflammatory factors in human fibroblast-like synoviocytes (HFLS) and the underlying mechanism. Human fibroblast-like synoviocytes (HFLS) were cultured in vitro at 37 °C in Dulbecco's modified Eagle's medium (DMEM) supplemented with 5 % fetal bovine serum (FBS) in a humidified incubator containing 5 % CO2. Cell viability was determined using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-tetrazolium bromide (MTT) assay, while real-time quantitative polymerase chain reaction (qRT-PCR) was used to determine the expressions of interleukin 1β (IL-1β) and interleukin 6 (IL-6) mRNAs. The expressions of p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB) were determined using Western blotting. Enzyme-linked immunosorbent assay (ELISA) was used to determine the levels of IL-1β and IL-6 in cell lysate. Treatment with 5-25 μM gentiopicrin did not significantly affect the number of viable cells, when compared with control group (p > 0.05). However, at 50 and 100 μM gentiopicrin, the number of viable cells were significantly increased, relative to control group (p < 0.05). Results of qRT-PCR showed that the expression levels of IL-1β and IL-6 mRNAs were significantly higher in TNF-α group than in control group (p < 0.05). However, treatment with gentiopicrin significantly and dose-dependently decreased their expression levels compared with TNF-α group (p < 0.05). Western blotting results showed that the expressions of p-p38MAPK and NF-κB-p65 proteins were significantly upregulated in TNF-α group, when compared with control group (p < 0.05). However, treatment with gentiopicrin significantly and dose-dependently down-regulated the expression of these proteins compared with TNF-α group (p < 0.05). The levels of IL-1β and IL-6 in cell lysate were significantly higher in TNF-α group than in control group (p < 0.05). However, treatment with gentiopicrin, and p38MAPK/NF-κB pathway inhibitors (SB203580 and BAY11-7082) significantly reduced the levels of these inflammatory factors compared with TNF-α group (p < 0.05).  Gentiopicrin has therapeutic potential for Rheumatoid arthritis (RA  ) through a mechanism involving the inhibition of p38MAPK/NF-κB pathway.

Topics: Arthritis, Rheumatoid; Cell Survival; Cells, Cultured; Fibroblasts; Humans; Imidazoles; Interleukin-1beta; Interleukin-6; Iridoid Glucosides; NF-kappa B; Nitriles; p38 Mitogen-Activated Protein Kinases; Plant Extracts; Pyridines; RNA, Messenger; Signal Transduction; Sulfones; Synoviocytes; Transcription Factor RelA; Tumor Necrosis Factor-alpha

Rheumatoid arthritis (RA) is the most common inflammatory arthritis and is a major cause of disability. The nuclear factor-kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway has been reported to be involved in the pathogenesis of RA with unclear mechanisms. Therefore, this study aims to explore the effect of NF-κB pathway on proliferation, apoptosis, and angiogenesis of human fibroblast-like synovial cells (HFLS) in RA.. Normal HFLS and RA-HFLS were selected as the normal and control groups, respectively. RA-HFLS were treated by BAY11-7082 (an inhibitor of NF-κB) in different concentrations, namely 2.5 μmol/L BAY11-7082, 5 μmol/LBAY11-7082 and 10 μmol/L BAY11-7082. MTT assay was employed to detect cell proliferation. Cell apoptosis was determined by flow cytometry at 24, 48, and 72 hours after culture. Western blot analysis was employed to detect the expressions of NF-κB, angiogenesis-related factors (VEGF, Ang1, and Ang2).. Initially, we found that BAY11-7082 inhibited NF-κB expression in a concentration-dependent manner. According to the findings of MTT assay and flow cytometry, we understood that RA-HFLS treated by BAY11-7082 (an inhibitor of NF-κB), the inhibition of NF-κB pathway, suppressed RA-HFLS proliferation and induced RA-HFLS apoptosis in a concentration and time-dependent manner. Furthermore, RA-HFLS treated by BAY11-7082 presented decreased VEGF, Ang1 and Ang2 expressions in a concentration-dependent manner.. The study concluded that inhibition of NF-κB pathway induced cell apoptosis and suppressed proliferation and angiogenesis of RA-HFLS, which could serve as a novel target in the treatment of RA.

Topics: Apoptosis; Arthritis, Rheumatoid; Cell Proliferation; Cells, Cultured; Humans; Myofibroblasts; Neovascularization, Pathologic; NF-kappa B; Nitriles; Ribonuclease, Pancreatic; Signal Transduction; Sulfones; Synoviocytes; Vascular Endothelial Growth Factor A; Vesicular Transport Proteins

Advanced oxidation protein products (AOPPs) have been shown to participate in the progression of rheumatoid arthritis (RA). However, the effect of AOPPs accumulation on catabolic effect in human chondrocyte and the underlying mechanism(s) remain unclear. The present study demonstrated that AOPPs inhibited cell viability and glycosaminoglycan (GAG) production in human chondrocyte. Exposure of chondrocyte to AOPPs significantly increased the production of catabolic factors, such as cyclooxygenase-2 (COX-2), matrix metalloproteinase 3 (MMPs)-3 and MMP-13. AOPPs stimulation induced ROS generation and NF-κ B p65 phosphorylation, which could be inhibited by soluble receptor for advanced glycan end products (sRAGE), NADPH oxidase inhibitor (apocynin), ROS scavenger (N-acetyl-cysteine, NAC). Furthermore, NF-κ B inhibitor Bay11-7082 significantly reversed the AOPPs-induced expression of catabolic factors and phosphorylation of NF-κ B p65. Targeting AOPPs-triggered catabolic effect might be as a promising option for patients with RA.

Topics: Advanced Oxidation Protein Products; Aged; Arthritis, Rheumatoid; Chondrocytes; Cyclic AMP Receptor Protein; Cyclooxygenase 2 Inhibitors; Female; Glycation End Products, Advanced; Glycosaminoglycans; Humans; Male; Matrix Metalloproteinase 13; Matrix Metalloproteinase 3; Middle Aged; NF-kappa B; Nitriles; Oxidation-Reduction; Signal Transduction; Sulfones

IL-23 is produced by antigen presenting cells and plays critical roles in immune response in rheumatoid arthritis. In this study, we investigated whether the RhoA/Rho-kinase pathway is required to elevate TLR2-mediated IL-23 production in synovial macrophages from patients with rheumatoid arthritis (RA), and then examined the suppressive effect of cilostazol on these pathways. IL-23 production was elevated by lipoteichoic acid (LTA), a TLR2 ligand, and this elevation was more prominent in RA macrophages than in those from peripheral blood of normal control. LTA increased the activation of RhoA in association with increased the nuclear translocation of NF-κB and its DNA-binding activity. Pretreatment of RA macrophages with the pharmacological inhibitors exoenzyme C3 (RhoA), Y27632 (Rho-kinase) or BAY11-7082 (NF-κB) inhibited IL-23 production by LTA. Inhibition of the RhoA/Rho-kinase pathway by these drugs attenuated NF-κB activation. Cilostazol suppressed the TLR2-mediated activation of RhoA, decreased NF-κB activity with down-regulated IL-23 production, and these effects were reversed by Rp-cAMPS, as an inhibitor of cAMP-dependent protein kinase. The expression of IL-23, which colocalized with CD68⁺ cells in knee joint of CIA mice, was significantly attenuated by cilostazol along with the decreased severity of arthritis. Taken together, the RhoA/Rho-kinase pathway signals TLR2-stimulated IL-23 production in synovial fluid macrophages via activation of NF-κB. Thus it is summarized that cilostazol suppresses TLR2-mediated IL-23 production by suppressing RhoA pathway via cAMP-dependent protein kinase activation.

Topics: ADP Ribose Transferases; Amides; Animals; Arthritis, Rheumatoid; Botulinum Toxins; Case-Control Studies; Cilostazol; Cyclic AMP; Humans; Interleukin-23; Knee Joint; Lipopolysaccharides; Macrophages; Male; Mice; Mice, Inbred DBA; NF-kappa B; Nitriles; Pyridines; Reference Values; rho-Associated Kinases; rhoA GTP-Binding Protein; Signal Transduction; Sulfones; Synovial Fluid; Teichoic Acids; Tetrazoles; Thionucleotides; Toll-Like Receptor 2

NF-kappaB inhibitors applied to animal models of rheumatoid arthritis (RA) demonstrate the important role of NF-kappaB in the production of mediators of inflammation in the joint and their antiinflammatory effects. Because NF-kappaB is involved in the differentiation, activation, and survival of almost all cells, its prolonged inhibition might have unwanted adverse effects. Therefore, we sought to apply NF-kappaB inhibitors more specifically, targeting dendritic cell (DC) differentiation, in order to influence the outcome of the autoimmune response, rather than to produce a broad antiinflammatory effect. We tested whether DCs treated with the NF-kappaB inhibitor BAY 11-7082 and exposed to arthritogenic antigen would suppress established arthritis in C57BL/6 mice.. Antigen-induced arthritis was generated in C57BL/6 mice by injection of methylated bovine serum albumin (mBSA). After mBSA challenge, mouse knee joints were injected with antigen-exposed BAY 11-7082-treated DCs or with soluble tumor necrosis factor receptor (sTNFR). Intraarticular injection of interleukin-1 (IL-1) was used to induce disease flare.. Inflammation and erosion were suppressed in mice that received mBSA-exposed BAY 11-7082-treated DCs, but not in those that received keyhole limpet hemocyanin-exposed BAY 11-7082-treated DCs. Clinical improvement was dependent on IL-10 and was associated with antigen-specific suppression of the delayed-type hypersensitivity (DTH) reaction and switching of anti-mBSA antibody isotype from IgG2b to IgG1 and IgA. Suppression of the DTH reaction or arthritic disease was not impaired by concomitant administration of sTNFR. Suppression could be reversed with intraarticular administration of IL-1beta and could be restored by a second injection of mBSA-exposed BAY 11-7082-treated DCs.. BAY 11-7082-treated DCs induce antigen-specific immune suppression in this model of inflammatory arthritis, even after full clinical expression of the disease. Such DCs have potential as antigen-specific therapy for autoimmune inflammatory arthritis, including RA.

Topics: Animals; Antigens; Arthritis, Rheumatoid; Dendritic Cells; Disease Models, Animal; Hypersensitivity, Delayed; Immunoglobulin A; Immunoglobulin G; Immunoglobulin M; Mice; Mice, Inbred C57BL; NF-kappa B; Nitriles; Serum Albumin, Bovine; Sulfones