miR-15a-5p regulates myocardial fibrosis in atrial fibrillation by targeting Smad7

PeerJ

article

Dan He¹  Zhong-bao Ruan¹  Gui-xian Song¹  Ge-cai Chen¹  Fei Wang¹  Mei-xiang Wang¹  Mao-kun Yuan³  Li Zhu¹ 

[1] Department of Cardiology, Jiangsu Taizhou People’s Hospital;Dalian Medical University Graduate School of Medicine;Department of Cardiothoracic Surgery, Jiangsu Taizhou People’s Hospital

关键词: MiR-15a-5p;    Myocardial fibrosis;    Smad7;    TGF-β1;    Atrial fibrillation;   

DOI  :  10.7717/peerj.12686

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

BackgroundAt present, there is no effective treatment for myocardial fibrosis in atrial fibrillation (AF). It is reported that miR-15a-5p is abnormally expressed in AF patients but its specific role remains unclear. This study aims to investigate the effect of miR-15a-5p in myocardial fibrosis.MethodsLeft atrial appendage (LAA) tissues were collected from AF and non-AF patients. In lipopolysaccharide (LPS) stimulated H9C2 cells, miR-15a-5p mimic, inhibitor, pcDNA3.1-Smad7 and small interfering RNA-Smad7 (siRNA-Smad7) were respectively transfected to up-regulate or down-regulate the intracellular expression levels of miR-15a-5p and Smad7. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB) were used to determine the expression levels of miR-15a-5p, Smad7, transforming growth factor β1 (TGF-β1) and collagen I. Cell counting kit-8 (CCK-8) and ethylene deoxyuridine (EdU) were used to determine cell viability and proliferation capacity, respectively. Dual-luciferase was used to detect whether miR-15a-5p interacted with Smad7, hydroxyproline (HYP) and Hematoxylin-Eosin (HE) staining were used to detect tissue fibrosis.ResultsThe expression levels of miR-15a-5p, TGF-β1 and collagen I were up-regulated, while Smad7 was down-regulated in AF tissues and LPS-stimulated cells. MiR-15a-5p mimic can inhibit the expression of Smad7, and the dual-luciferase experiment confirmed their interaction. MiR-15a-5p inhibitor or pcDNA3.1-Smad7 can inhibit LPS-induced fibrosis and cell proliferation, while siRNA-Smad7 can reverse the changes caused by miR-15a-5p inhibitor.ConclusionWe combined clinical studies with LPS-stimulated H9C2 cell model to validate the role of miR-15a-5p in the regulation of Smad7 and fibrosis. Taken together, the miR-15a-5p/Smad7 pathway might be a potential target for AF therapy.

【 授权许可】

CC BY