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Rheumatoid arthritis (RA) is a persistent autoimmune disease. Fibroblast-like synoviocytes (FLS) are a key component of invasive pannus and a pathogenetic mechanism in RA. Expression of bone morphogenetic protein 3 (BMP3) mRNA is reportedly decreased in the arthritic synovium. We previously showed that BMP3 expression is significantly downregulated in the synovial tissues of RA patients and models of adjuvant-induced arthritis (AIA). In the present study, we explored the association between BMP3 and FLS migration and secretion of proinflammatory factors in RA. We found that inhibition of BMP3 expression using BMP3 siRNA increased the proinflammatory chemokines and migration of FLS stimulated with TNF-α. Inhibition of BMP3 expression also increased expression of IL-6, IL-1β, IL-17A, CCL-2, CCL-3, VCAM-1, MMP-3, and MMP-9, but not TIMP-1, in AIA and RA FLS. Correspondingly, induction of BMP3 overexpression through intra-articular injection of ad-BMP3 diminished arthritis severity in AIA rats. We also found that BMP3 may inhibit activation of TGF-β1/Smad signaling. These data indicate that BMP3 may suppress the proliferation and migration of FLS via the TGF-β1/Smad signaling pathway.

Background: Rheumatoid arthritis (RA) is characterized by a tumor-like expansion of the synovium and the subsequent destruction of adjacent articular cartilage and bone. Recent studies have shown that phosphatase and tension homolog deleted on chromosome 10 (PTEN) might contribute to the survival of fibroblast-like synoviocytes (FLS) and the production of pro-inflammatory cytokines in RA.Methods : The expression was determined in RA and adjuvant-induced arthritis (AIA) synovial tissues by immunohistochemistry. FLSs were treatment with bpv, PTEN-RNAi or over-expression plasmid in RA and AIA. FLSs migration was assessed. The ad-PTEN was also injected into the knee of AIA in vivo. Chromatin Immunoprecipitation (ChIP) and Methylation-special PCR (MSP) assay were used to study the expression of PTEN mRNA in DNA methylation.Results : Down-regulated level of PTEN expression was observed in RA and AIA. Inhibition PTEN expression by bpv or PTEN-RNAi could promote the expression of pro-inflammatory cytokines, chemokines and migration of FLS with TNF-α in RA and AIA. Consistently, over-expression of PTEN reduced their low-expression of pro-inflammatory cytokines, chemokines and migration. Intra-articular injection of ad-PTEN in AIA knees dramatically reduced inflammatory and paw swelling in vivo. The ChIP and MSP assay has clearly detected the DNA methylation of PTEN was increased in FLS with TNF-α. Moreover, intraperitoneally injected 5-Aza in AIA also suppressed the inflammatory and paws swelling in vivo.Conclusions: Our findings suggest that over-expression PTEN attenuates the formation of pro-inflammatory cytokines, chemokines and migration of FLS, and it may be regulated by DNA methylation in the pathogenesis of RA.

Liver fibrosis is a persistent pathological repair of chronic liver injury, which is characterized by excessive deposition of collagen-dominated extracellular matrix (ECM). It is well known that hepatic fibrosis can be reversed in the absence of etiology. Studies have shown that long non-coding RNA (Lnc RNA) maternally expressed gene3 (MEG3) has strong effects on the activation of hepatic stellata cells (HSCs). However, the function of MEG3 in the reversal of liver fibrosis has not been studied. In this experiment, we studied the content expression, function, and part of the potential mechanism of MEG3 in reversing liver fibrosis. In in vivo and in vitro models, we found that MEG3 was down-regulated during the formation of liver fibrosis, while it was up-regulated during the reversal of liver fibrosis. Then, it was found that the silencing of MEG3 could gradually restore the activity of the inactivated LX-2 cells, Overexpression of MEG3 can inhibit the activation of LX-2 cells, accelerate the reversal of liver fibrosis. Through catRAPID analysis, it was found that NLR family CARD domain containing 5 (NLRC5) may be a target of MEG3. We found that, after MEG3 silencing, NLRC5 expression was upregulated in LX-2 cells in the reverse phase, while, after MEG3 overexpression, NLRC5 expression was decreased. Further, we verified that MEG3 can target NLRC5 through RNA pull down experiment. Therefore, MEG3 may inhibit the activation of hepatic stellate cells by targeting NLRC5, thus accelerating the reversal of hepatic fibrosis.

Via promoting synovitis, pannus growth and cartilage/bone destruction, fibroblast-like synovial cells (FLSs) play a significant role in the pathogenesis of rheumatoid arthritis (RA). In our study, rats were induced with complete freund's adjuvant (CFA) to be animal models for studying the RA pathogenesis. Microtubule-associated Serine/Threonine-protein kinase 3 (MAST3) has been documented to play a critical role in regulating the immune response of IBD (Inflammatory bowel disease) and involved in the process of cytoskeleton organization, intracellular signal transduction and peptidyl-serine phosphorylation, but its role in the progression of RA remains unknown and is warranted for investigation. So, we tried our best to investigate the mechanism and signaling pathway of MAST3 in RA progression. In the synovial tissue and FLSs of AA rats, we have found that MAST3 was significantly up-regulated than normal. Furthermore, MAST3 overexpression could promote proliferation and inflammatory response of FLSs. In the aspect of mechanism, we discovered that the expression of MAST3 might involve in NF-κB signaling pathway in RA. On the whole, our results suggested that MAST3 might promote the proliferation and inflammation of FLSs by regulating NF-κB signaling pathway.

Background: Rheumatoid arthritis (RA) is characterized by a tumor-like expansion of the synovium and the subsequent destruction of adjacent articular cartilage and bone. Recent studies have shown that phosphatase and tension homolog deleted on chromosome 10 (PTEN) might contribute to the survival of fibroblast-like synoviocytes (FLS) and the production of pro-inflammatory cytokines in RA. Methods: The expression was determined in RA and adjuvant-induced arthritis (AIA) synovial tissues by immunohistochemistry. FLSs were treatment with bpv, PTEN-RNAi or over-expression plasmid in RA and AIA. FLSs migration was assessed. The ad-PTEN was also injected into the knee of AIA in vivo. Chromatin Immunoprecipitation (ChIP) and Methylation-special PCR (MSP) assay were used to study the expression of PTEN mRNA in DNA methylation. Results: Down-regulated level of PTEN expression was observed in RA and AIA. Inhibition PTEN expression by bpv or PTEN-RNAi could promote the expression of pro-inflammatory cytokines, chemokines and migration of FLS with TNF-α in RA and AIA. Consistently, over-expression of PTEN reduced their low-expression of pro-inflammatory cytokines, chemokines and migration. Intra-articular injection of ad-PTEN in AIA knees dramatically reduced inflammatory and paw swelling in vivo. The ChIP and MSP assay has clearly detected the DNA methylation of PTEN was increased in FLS with TNF-α. Moreover, intraperitoneally injected 5-Aza in AIA also suppressed the inflammatory and paws swelling in vivo. Conclusions: Our findings suggest that over-expression PTEN attenuates the formation of pro-inflammatory cytokines, chemokines and migration of FLS, and it may be regulated by DNA methylation in the pathogenesis of RA. Funding Statement: This study is supported by the National Natural Science Foundation of China (No. 81770609). Declaration of Interests: All authors declare no conflict interests. Ethics Approval Statement: All experimental protocols used on the animals were approved by the institutions’ subcommittees on animal care of Anhui Medical University (approval number: 20160253).

Background/aims Rheumatoid arthritis (RA) is characterized by a tumor-like expansion of the synovium and the subsequent destruction of adjacent articular cartilage and bone. Recent studies have shown that phosphatase and tension homolog deleted on chromosome 10 (PTEN) might contribute to the surviva of fibroblast-like synoviocytes (FLSs) and the production of pro-inflammatory cytokines in RA. The purpose of this study was to explore the functions and underlying mechanisms of PTEN in the proliferation and migration of FLSs. Methods FLSs were obtained from adjuvant-induced arthritis (AIA) and normal rats. The expression levels of PTEN, c-Myc, cyclin D1, PCNA, and MMP-9 were detected by quantitative-real-time-PCR and western blot assay. A BrdU proliferation assay, cell cycle analysis, and a wound-healing assay were used to study the role of PTEN in FLSs treated with PTEN inhibitor bpv, specific small interfering RNA targeting PTEN (PTEN-RNAi) or a PTEN over-expression vector (PTEN-GV141). Chromatin immunoprecipitation and methylation-special PCR assays were used to study the expression of PTEN mRNA in the presence of DNA methylation. Results PTEN expression was downregulated in AIA FLSs in comparison to normal rats. Moreover, inhibition of PTEN expression by bpv or PTEN-RNAi could promote the proliferation and migration of FLSs, and increase the expression of c-Myc, cyclin D1, PCNA, and MMP-9 in AIA FLSs, but had no effect on TIMP-1 expression.In addition, transfection of AIA FLSs with PTEN-GV141 reduced their proliferation and migration. Further study indicated that DNA methylation could regulate PTEN expression in AIA. Conclusion Our findings suggest that PTEN might play a pivotal role in the proliferation and migration of FLSs through the activation of the AKT signaling pathway. Additionally, PTEN expression may be regulated by DNA methylation in the pathogenesis of AIA.