Proliferation Of Rheumatoid Arthritis Synovial Cells Research Articles

Effect of Miao medicine, Jinwujiangu decoction, on IL- 17/IL-23 inflammatory axis of fibroblast-like synoviocytes in rheumatoid arthritis

Purpose: To explore the influence of the Miao medicine, Jinwujiangu decoction, on the interleukin (IL)- 17/IL-23 inflammatory axis of fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA).Methods: Synovial tissue samples were randomly divided into a blank control group, high-dose (0.06mg/mL), medium-dose (0.6mg/mL), and low-dose (6.0mg/mL) groups of Jinwujiangu decoction, a leflunomide group, and a tripterygium glycosides group. Proliferation of RA synovial cells was detected by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. Enzyme-linked immunosorbent assay (ELISA) was used to determine the secretion of IL-6, transforming growth factor beta (TGF-β), and IL-17. Real-time polymerase chain reaction was used to evaluate the expression of IL-23R, IL-17R, RAR-related orphan receptor alpha (RORα), RORγt, and signal transducer and activator of transcription (STAT3) mRNA. The protein activities of IL-17R, STAT3 and pSTAT3 were assessed by Western blot assay.Results: Jinwujiangu decoction inhibited the proliferation of RA synovial cells. Treatment with different drug concentrations resulted in downregulation of IL-6, TGF-β, and IL-17 secretion. The expression levels of IL-23R, IL-17R, RORα, RORγt, and STAT3 mRNA in RA-FLS were significantly reduced after intervention with different drugs. Protein expression levels of STAT3, pSTAT3, and IL-17 in the different drug treatment groups were significantly decreased.Conclusion: Jinwujiangu decoction inhibits the secretion of IL-6 and TGF-β in RA-FLS, and intervenes to regulate gene expression of IL-23/IL-17 inflammation axis and suppress immune inflammation. The results of this study provide new evidence for the study of anti-inflammatory mechanism of TCM compound prescription.Keywords: Jinwujiangu decoction, IL-17/IL-23, Fibroblast-like synoviocytes, Rheumatoid arthritis, Ethnomedicine

Involvement of poly(ADP-ribose) polymerase 1 inERBB2expression in rheumatoid synovial cells

Hyperplasia of synovial lining cells is one of the main features of rheumatoid arthritis (RA). We previously reported that ERBB2 is highly expressed in RA synovial cells and that it plays an important role in their hyperproliferative growth. Recent findings have suggested that poly(ADP-ribose) polymerase-1 (PARP-1) is involved in the transactivation of NF-kappaB-dependent genes such as ERBB2. In the present study, we investigated the role of PARP-1 in ERBB2 transcription in RA synovial cells. The expression level of PARP-1 was significantly high in synovial cells derived from three patients with RA, compared with three patients with osteoarthritis (OA). Luciferase assays revealed that PARP-1 augments the transcription of the ERBB2 gene and that a region between -404 and -368 is responsible for this activation. A protein with an apparent molecular mass of 115 kDa was isolated mainly from nuclear extracts of RA synovial cells with an affinity matrix harboring a DNA fragment identical to the above region. Mass spectrometric analysis demonstrated this protein to be PARP-1. Southwestern blot analysis showed that PARP-1 binds to this region, but not to adjacent regions. PARP-1 associates directly with NF-kappaB, and a chromatin immunoprecipitation assay indicated that these proteins interact with this enhancer region in the ERBB2 gene. Treatment of RA synovial cells with PARP-1 small interfering RNA attenuated their ERBB2 expression, while an inhibitor of the polymerase activity of PARP-1 had no effect. PARP-1 DNA binding is not required for transcriptional activation. These findings suggest that PARP-1 is involved in the expression of ERBB2 in concert with NF-kappaB, which might be associated with the proliferation of RA synovial cells.

Modulation by proinflammatory cytokines of Fas/Fas ligand-mediated apoptotic cell death of synovial cells in patients with rheumatoid arthritis (RA).

Synovial cell hyperplasia is a characteristic of patients with RA. Excessive proliferation of RA synovial cells is, in part, responsible for the synovial cell hyperplasia. In addition, synovial cell death that would reduce synovial cell number may be defective, leading to the hyperplasia. Thus, the defective control of cell death as well as cell proliferation may be of central importance in the pathogenesis of RA. In this study we analysed effects of proinflammatory cytokines on Fas/Fas ligand (FasL)-induced synovial cell apoptosis, and evaluated apoptosis-associated protein expression in the synovial cells in patients with RA. RA synovial cells expressed Fas antigen and lymphocytes infiltrating into RA synovium expressed FasL. Apoptotic synovial cells were detected within the sublining layer of RA synovium. Anti-Fas MoAb induced apoptosis of RA synovial cells in vitro, and proinflammatory cytokines tumour necrosis factor-alpha (TNF-alpha) and IL-1beta, but not IL-6 or IL-8, inhibited the anti-Fas-induced apoptosis accompanying up-regulation of Bcl-2 protein expression and reduced expression of CPP32 and ICH-1L. Immunohistochemical study revealed that CPP32 and ICH-1L were expressed weakly in the RA synovial lining cells compared with osteoarthritis (OA) synovial lining cells. Thus, we found that although RA synovial cells could die via apoptosis through Fas/FasL pathway, apoptosis of synovial cells was inhibited by proinflammatory cytokines present within the synovium. Inhibition of apoptosis by the proinflammatory cytokines may contribute outgrowth of synovial cells that leads to pannus formation and the destruction of joints in patients with RA.

Modulation of synovial cell function by somatostatin in patients with rheumatoid arthritis.

To elucidate the role of neurologic, endocrine, and immune system interactions in the development of pathologic responses in patients with rheumatoid arthritis (RA), we studied somatostatin (SOM) production and somatostatin receptor (SOMR) expression in RA synovium and its function in patients with RA. The effects of SOM on proinflammatory cytokine (interleukin-6 [IL-6] and IL-8) and collagenase production by RA synovial cells were estimated by enzyme-linked immunosorbent assay, and their messenger RNA expression was assessed by reverse transcription-polymerase chain reaction (RT-PCR) using limiting dilutions of the complementary DNA. The expression of SOMR by RA synovial cells was also studied by RT-PCR. Local production of SOM was estimated by RT-PCR and immunohistochemical staining. Physiologic concentrations (approximately 10(-10)M) of SOM inhibited proliferation of RA synovial cells. The production of proinflammatory cytokines and matrix metalloproteinases by RA synovial cells was also modulated by SOM. SOMR subtypes 1 and 2 were expressed on fibroblast-like synovial cells, and the expression of SOMR-2 was up-regulated by proinflammatory cytokine treatment of the synovial cells from patients with RA. RA fibroblast-like cells synthesized SOM by themselves, suggesting that SOM acts as an autocrine regulator of synovial cell function in patients with RA. SOM inhibited aberrant synovial cell function in patients with RA, suggesting possible clinical applications of this neuropeptide.