Sex steroid receptors in rheumatoid arthritis

Rheumatoid arthritis (RA) is a disease characterized primarily by chronic inflammatory synovitis and is well-known to be associated with significant sex differences in its prevalence and clinical features. Sex steroids have been proposed to be involved in the pathogenesis of RA, but details pertaining to the expression of sex steroid receptors in RA synovial tissue have yet to be fully characterized. In the present study, we examined oestrogen receptor (ER) α, ERβ, progesterone receptor (PR) and androgen receptor (AR) mRNA expression using real-time reverse transcriptase–PCR (RT-PCR) in eight female RA synovial tissues and six female synovial tissues without inflammation, and determined immunolocalization of ERα, ERβ, PR-A, PR-B and AR using immunohistochemistry in synovial tissues obtained from 22 RA patients. Real-time RT-PCR analysis demonstrated the expression of ER, PR and AR mRNAs in both RA and non-inflamed synovial tissues. Relative abundance of ER mRNAs was significantly higher in RA synovial tissue than non-inflamed synovial tissue (P<0.05). In addition, the relative ERα/ERβ mRNA expression ratio was significantly lower in RA than non-inflamed synovial tissue (RA, 2.34±1.60; and non-inflamed, 20.7±19.1; P<0.05). There were no significant differences in relative abundance of PR mRNA. Relative abundance of AR mRNA was significantly lower in RA (P<0.05). Immunoreactivity for ERα, ERβ, PR-B and AR was detected in the lining cells, inflammatory cells and fibroblasts in all the patients examined. The labelling indices for ERβ and PR-B were more abundant in both lining cells (ERβ, 54.2±12.2%; PR-B, 73.6±18.9%) and inflammatory cells (ERβ, 74.6±16.2%; PR-B, 75.9±16.1%) than in fibroblasts (ERβ, 36.5±15.6%; PR-B, 49.4±18.0%). Labelling indices for ERα and AR were significantly higher in lining cells (ERα, 14.4±8.6%; AR, 31.2±11.3%) and fibroblasts (ERα, 12.1±7.5%; AR, 20.1±9.6%) than those in inflammatory cells (ERα, 5.7±3.3%; AR, 9.2±4.4%). There were significant differences (P<0.05) in the labelling indices for ERα, ERβ and PR-B between men and women under 50 years of age in fibroblasts of RA synovial tissues. These results indicate that sex steroid receptors are present in RA and non-inflamed synovial tissues, including inflammatory cells in RA, and suggest that sex steroids may play important roles in the regulation of inflammation of RA synovial tissue.

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The Function and Molecular Mechanism of MicroRNA-429 in Rheumatoid Arthritis

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2020.2352 ◽

2020 ◽

Vol 10 (7) ◽

pp. 945-950

Author(s):

Pengdong Zhang ◽

Bailong Yu ◽

Bin Lei ◽

Changlin Li ◽

Xiaoqiang Yuan

Keyword(s):

Rheumatoid Arthritis ◽

Gene Expression ◽

Molecular Mechanism ◽

Synovial Tissue ◽

Luciferase Assay ◽

Rt Pcr ◽

Tnf Α ◽

Tlr4 Gene ◽

Synovial Tissues ◽

D Model

Objective: To explain the function and molecular mechanism of miRNA-429 in Rheumatoid Arthritis development. Methods: Collecting synovial tissue of 36 RA patients and 36 traumatic amputation patients, the miRNA-429 and TLR4 gene expressions were measured by RT-PCR. The SD rats were divided into NC, 14 d Model and 28 d Model groups. The IL-1β and TNF-α concentrations of serum were measured by Elisa assay in difference rats groups; The synovial tissue pathology was evaluated by HE staining; the miRNA-429 gene expression of rats groups were measured by RT-PCR, the TLR4 and NF-κB proteins expressions of rats groups were evaluated by IHC staining; the correlation between miRNA-429 and TLR4 were evaluated by Double luciferase assay. Results: Compared with normal synovial tissues, the miRNA-429 and TLR4 gene expression of synovial tissues were significantly difference in RA patients. In rats vivo study, we found that IL-1 and TNF-α concentrations were significantly up-regulation with time increasing (P < 0 05, respectively); inflammation degree was serious by HE staining and miRNA-429 gene expression was significantly reduced (P < 0.05, respectively); TLR4 and NF-κB proteins expressions were significantly up-regulation (P < 0.05, respectively) with time increasing; TLR4 was the target gene of miRNA-429 by Double luciferase assay. Conclusion: miRNA-429 over-expression stimulated RA development.

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Urocortin in the synovial tissue of patients with rheumatoid arthritis

Clinical Science ◽

10.1042/cs1000577 ◽

2001 ◽

Vol 100 (6) ◽

pp. 577-589 ◽

Cited By ~ 21

Author(s):

Miwa UZUKI ◽

Hironobu SASANO ◽

Yasunari MURAMATSU ◽

Kazuhito TOTSUNE ◽

Kazuhiro TAKAHASHI ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Synovial Fluid ◽

Synovial Tissue ◽

High Power ◽

Rt Pcr ◽

Active Stage ◽

High Power Field ◽

Mrna In Situ Hybridization ◽

Synovial Tissues

Urocortin is a newly identified member of the corticotropin-releasing factor (CRF) neuropeptide family, and is known to be involved in the modulation of the inflammatory process. We examined the expression of urocortin, CRF and their receptors (CRF receptor; CRF-R) in the synovial tissue of patients with rheumatoid arthritis (RA) in order to study the possible biological roles of urocortin. Synovial tissues/fluids were obtained from 38 patients with RA, nine patients with osteoarthritis and four with trauma. We studied the concentration of urocortin in the synovial fluid using RIA, and the expression of urocortin in synovial tissue using immunohistochemistry, mRNA in situ hybridization and reverse transcriptase–PCR (RT-PCR). In addition, we examined the immunolocalization of CRF and the expression of CRF-R1, -R2-α and -R2-β mRNAs utilizing RT-PCR in these synovial tissues. Urocortin concentrations in synovial fluid were higher in RA patients (79.8±154 pg/ml) than in control patients (12.3±4.8 pg/ml; P ≤ 0.05). Urocortin immunoreactivity and mRNA signals were both detected in synovial cells, lymphocytes, fibroblasts and macrophages. The number of urocortin-positive cells in the synovium was significantly higher in RA (73.1±32.1 cells per high-power field) than in control (18.4±10.4 cells per high-power field) patients. In addition, both urocortin immunoreactivity and mRNA signals in the synovium reached maximum levels in the active stage of RA inflammation. Moreover, the number of immunoreactive urocortin-positive cells was significantly correlated with the urocortin concentration in synovial fluid (r = 0.705; P < 0.001) and with histologically defined local inflammatory activity (r = 0.641; P < 0.001). The distribution and number of immunoreactive CRF-positive cells in synovial tissue were similar to those of urocortin-positive cells (r = 0.701; P < 0.001). Urocortin, CRF-R1 and CRF-R2-α mRNAs detected by RT-PCR were expressed in in the synovium of 10/10, 10/10 and 2/10 RA patients respectively, but CRF-R2-β was not expressed. Urocortin was actively synthesized in the synovium of RA patients. The present study suggests that urocortin may play an important role as an autocrine and/or paracrine regulator of synovial inflammation in RA.

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