circCDYL对大鼠心脏成纤维细胞活化的影响及其作用机制研究OA

Objective To investigate the effect of circCDYL on the activation of rat cardiac fibroblasts and its underlying mechanism.Methods Cardiac fibroblasts were isolated from neonatal SD rats and cultured.The cells were divided into groups A to D.Group A was not treated with reagents,Group B was treated with angiotensin Ⅱ(Ang Ⅱ),Group C was transfected with si-NC and then treated with Ang Ⅱ,Group D was transfected with si-circCDYL and then treated with Ang Ⅱ.RT-qPCR was used to detect the relative expression level of circCDYL and the relative mRNA expression levels of extracellular matrix-related genes(Col1a1,Col3a1,FN1).Cell proliferation was assessed using EdU staining and the CCK-8 assay.The expression level of α-SMA was detected by immunofluorescence staining.The phosphorylation level of Smad2 protein was detected by Western blot.Results RT-qPCR showed that the relative expression of circCDYL in rat cardiac fibroblasts gradually increased over time after Ang Ⅱ treatment for 6,12,24 and 48 h(F=338.30,P＜0.05).Compared with group C,group D showed significantly reduced relative expression of circCDYL(F=16.06,q=5.98,P＜0.05).EdU staining showed that the proportion of EdU-positive cells in group D was significantly reduced compared with that in group C(F=14.76,q=7.19,P＜0.05).CCK-8 assay showed that between 12 and 72 h of culture,the absorbance values of group D were significantly lower than those of group C(F=24.19-303.60,q=25.35-31.75,P＜0.05).RT-qPCR,immunofluorescence staining,and Western blot respectively showed that compared with group C,group D exhibited significantly reduced relative mRNA expression levels of Col1a1,Col3a1,and FN1,mean fluorescence intensity of α-SMA,and p-Smad2/Smad2 ratio(F=16.66-86.28,q=5.48-10.99,P＜0.05).Conclusion circCDYL promotes the acti-vation of rat cardiac fibroblasts,and the mechanism may be related to the promotion of Smad2 phosphorylation in the TGF-β/Smad signaling pathway.