Résumé
AIM: To investigate the effects of transient receptor potential channel 6 (TRPC6) on the proliferation of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS) induced by IL-1β.METHODS: The mRNA expression of TRPC6 in synovial tissues from RA or OA patients was studied by RT-qPCR.RA-FLS were cultured by enzyme digestion and tissue adhesion methods.The method of flow cytometry was applied to identify the RA-FLS.RA-FLS were treated with different concentrations (0, 0.25, 0.5, 1, 2, 4, 8 and 16 μg/L) of IL-1β for 36 h.The cell viability was examined by CCK-8 assay.RA-FLS were incubated with IL-1β (16 μg/L) for different time (12, 24, 36, 48, 60 and 72 h), and the cell viability was measured by CCK-8 assay.The interference efficiency of TRPC6-siRNA was determined by RT-qPCR and Western blotting.After incubation in the presence or absence of IL-1β medium, the cell viability, the percentage of EdU-positive cells and the percentage of (G2/M+S) phase were measured by CCK-8 assay, EdU labeling assay and flow cytometry, respectively.RESULTS: The mRNA expression of TRPC6 was found in synovial tissue with higher levels in RA patients than that in OA patients.TRPC6-siRNA significantly decreased the mRNA and protein expression of TRPC6 (P<0.05).When RA-FLS were treated with IL-1β, the proliferation of RA-FLS was increased (P<0.05).The differences of the cell viability, the percentage of EdU-positive cells and the (G2/M+S) phase percentage between TRPC6-siRNA group and blank control group or NC-siRNA group were significant, in the presence of IL-1β (P<0.05).However, they were not significant in the absence of IL-1β.CONCLUSION: TRPC6 is involved in the proliferation of RA-FLS induced by IL-1β.Silencing of TRPC6 gene inhibits the growth of RA-FLS induced by IL-1β.
Résumé
BACKGROUND:Triggering receptor expressed on myeloid cel s 2 (TREM-2) is highly expressed throughout the synovial tissue in active rheumatoid arthritis patients, but the role of TREM-2 in the pathogenesis of rheumatoid arthritis stil remains unclear. OBJECTIVE:To explore the TREM-2 expression in the synovial tissue of col agen type II-induced arthritis rats. METHODS:The col agen-induced arthritis models were established in rats. The activity indicators and pathological changes of arthritis synovial were dynamical y observed. The mRNA levels of TREM-2, tumor necrosis factor-α, interleukin-1β, and interleukin-10 were detected in synovial tissue of rats by RT-PCR. The protein expression and location of TREM-2 were measured with western blot assay and immunohistochemistry, respectively. RESULTS AND CONCLUSION:At day 13 after immunization, the paws of model rats appeared red and swel ing, the arthritis index scores were increased (P<0.01). At day 19-25 after immunization, the inflammation reached the peak. Hematoxylin-eosin staining showed that, the synovium of col agen-induced arthritis rats were proliferated and were infiltrated by inflammatory cel s, cartilage was destroyed. Compared with the control group, the expression of TREM-2 mRNA and protein, the mRNA levels of tumor necrosis factor-αand interleukin-1βin synovial tissue of the model rats were significantly increased (P<0.05 or P<0.01), while interleukin-10 mRNA expression was significantly decreased (P<0.05). Experimental findings indicate that, TREM-2 is a crucial inflammatory regulator and the increasing expression of TREM-2 plays an important role in the pathogenesis of col agen-induced arthritis.