TY - JOUR AB - MicroRNAs (miRs) play important roles in the protection against and development of congenital heart disease (CHD). However, the role and potential mechanisms of miR‑219‑5p in cyanotic CHD remains unclear. Reverse transcription‑quantitative PCR (RT‑qPCR) was used to measure miR‑219‑5p levels in cyanotic CHD and hypoxia‑induced H9C2 cells. Dual luciferase reporter gene assay was used to confirm whether liver receptor homolog‑1 (LRH‑1) was a direct target of miR‑219‑5p. miR‑219‑5p inhibitor and LRH‑1‑small interfering RNA were transfected into H9C2 cells under hypoxic conditions to investigate the role of miR‑219‑5p in hypoxia‑induced H9C2 cells. Subsequently, cell viability was detected using an MTT assay and cell apoptosis was detected using flow cytometry. In addition, RT‑qPCR and western blotting assays were performed to detect the mRNA and protein expression of LRH‑1, cyclin D1 and β‑catenin, respectively. The data showed that miR‑219‑5p expression was higher in patients with cyanotic CHD compared with patients with acyanotic CHD gradually increased in H9C2 cells with prolonged hypoxia time. Dual luciferase reporter assay results showed that LRH‑1 was a direct target gene of miR‑219‑5p. Inhibition of miR‑219‑5p reversed hypoxia‑induced cell viability reduction and attenuated hypoxia‑induced cell apoptosis. In addition, hypoxia induction inhibited the expression of LRH‑1, cyclin D1 and β‑catenin, which was reversed by miR‑219‑5p inhibitor. However, LRH‑1 downregulation reversed the miR‑219‑5p inhibitor enhanced cell viability, decreased cell apoptosis and increased expression of LRH‑1, cyclin D1 and β‑catenin in hypoxia‑treated cardiomyocytes. The present results demonstrated that downregulation of miR‑219‑5p promoted the expression of the LRH‑1/Wnt/β‑catenin signaling pathway‑associated components, reduced cardiomyocyte apoptosis and increased cell growth under hypoxic conditions. miR‑219‑5p may be a potential therapeutic target for cyanotic CHD therapy. AD - Department of Cardiopulmonary Surgery, Huai'an First People's Hospital, Huai'an, Jiangsu 223300, P.R. China AU - Hu,Chuanxian AU - Huang,Su AU - Wu,Fafu AU - Ding,Hui DA - 2021/01/01 DO - 10.3892/etm.2020.9468 IS - 1 JO - Exp Ther Med KW - congenital heart disease apoptosis microRNA‑219‑5p liver receptor homolog‑1/Wnt/β‑catenin signaling pathway PY - 2021 SN - 1792-0981 1792-1015 SP - 36 ST - MicroRNA‑219‑5p participates in cyanotic congenital heart disease progression by regulating cardiomyocyte apoptosis T2 - Experimental and Therapeutic Medicine TI - MicroRNA‑219‑5p participates in cyanotic congenital heart disease progression by regulating cardiomyocyte apoptosis UR - https://doi.org/10.3892/etm.2020.9468 VL - 21 ER -