Circ_LAS1L/miR-125b/Sfrp5通路抑制急性心肌梗死后心肌纤维化

Circ_LAS1L/miR-125b/Sfrp5 Pathway Inhibits Myocardial Fibrosis after Acute Myocardial Infarction

目的探讨circ_LAS1L/miR-125b/Sfrp5通路在心肌纤维化(MF)过程中的作用。方法心肌成纤维细胞转染后加入AngⅡ刺激培养;构建急性心肌梗死(AMI)小鼠模型后,尾静脉分别注射miR-125b antagomir、miR-125b antagomir加Sfrp5 siRNA、Sfrp5过表达质粒。CCK-8检测细胞存活力,Transwell检测细胞迁移,荧光定量PCR、Western blot、ELISA和免疫组化检测相关因子的表达水平,Masson染色检测小鼠MF水平。结果AngⅡ抑制circ_LAS1L和Sfrp5的表达,而促进miR-125b、α-SMA、CollagenⅠ和CollagenⅢ的表达(P均<0.05)。circ_LAS1L过表达、miR-125b inhibitors和Sfrp5过表达均能明显减弱AngⅡ的促存活、活化和迁移作用(P均<0.05)。miR-125b、α-SMA、CollagenⅠ和CollagenⅢ在AMI小鼠中的表达上调,而Sfrp5表达减少(P均<0.05)。抑制miR-125b表达和上调Sfrp5表达均能显著减少梗死面积和胶原纤维数量,并下调α-SMA、CollagenⅠ和CollagenⅢ的表达;同时抑制miR-125b和Sfrp5表达时,梗死面积和纤维化水平并无改善(P均>0.05)。结论miR-125b/Sfrp5通路上调可抑制小鼠急性心肌梗死后纤维化。

Objective Explore the role of circ_LAS1L/miR-125b/Sfrp5 pathway in myocardial fibrosis.Methods Cardiac fibroblasts(CFs)were transfected and cultured with AngⅡ stimulation. After establishing the acute myocardial infarction(AMI)mouse model,miR-125b antagomir,miR-125b antagomir plus Sfrp5 siRNA,or Sfrp5 overexpression plasmid was injected through tail vein of mice.Cell viability was detected by CCK-8,cell migration was detected by Transwell,the expression levels of related factors were detected by fluorescence quantitative PCR,Western blot,ELISA and immunohistochemistry,and the level of myocardial fibrosis in mice was detected by Masson staining. Results AngⅡ inhibited the expression of circ_LAS1L and Sfrp5 while promoting the expression of miR-125b,α-SMA,CollagenⅠ and CollagenⅢ(P all<0.05). Circ_LAS1L overexpression,miR-125b inhibitors and Sfrp5 overexpression could significantly attenuate the pro-survival,activation and migration effects of AngⅡ(P all<0.05). miR-125b,α-SMA,collagenⅠ and collagenⅢ were up-regulated in AMI mice,while Sfrp5 was down-regulated(P all<0.05). Inhibition of miR-125b expression and up-regulated of Sfrp5 expression significantly reduced infarct size and collagen fiber number,and downregulated the expression of α-SMA,CollagenⅠ,and CollagenⅢ. However,simultaneous inhibition of miR-125b and Sfrp5 expression did not significantly improve infarct size and fibrosis levels(P all>0.05). Conclusion The up-regulation of miR-125b/Sfrp5 pathway can inhibit fibrosis after acute myocardial infarction in mice.