Lin Ruizhu, Rahtu-Korpela Lea, Magga Johanna, Ulvila Johanna, Swan Julia, Kemppi Anna, Pakanen Lasse, Porvari Katja, Huikuri Heikki, Junttila Juhani, Kerkelä Risto
Research Unit of Biomedicine, Department of Pharmacology and Toxicology, University of Oulu, Aapistie 5, 90220 Oulu, Finland.
Research Unit of Biomedicine, Department of Pharmacology and Toxicology, University of Oulu, Aapistie 5, 90220 Oulu, Finland; Biocenter Oulu, University of Oulu, Aapistie 5, 90220 Oulu, Finland.
Mol Ther Nucleic Acids. 2020 Jun 5;20:589-605. doi: 10.1016/j.omtn.2020.04.001. Epub 2020 Apr 8.
Non-coding microRNAs (miRNAs) are powerful regulators of gene expression and critically involved in cardiovascular pathophysiology. The aim of the current study was to identify miRNAs regulating cardiac fibrosis. Cardiac samples of age-matched control subjects and sudden cardiac death (SCD) victims with primary myocardial fibrosis (PMF) were subjected to miRNA profiling. Old SCD victims with PMF and healthy aged human hearts showed increased expression of miR-1468-3p. In vitro studies in human cardiac fibroblasts showed that augmenting miR-1468-3p levels induces collagen deposition and cell metabolic activity and enhances collagen 1, connective tissue growth factor, and periostin expression. In addition, miR-1468-3p promotes cellular senescence with increased senescence-associated β-galactosidase activity and increased expression of p53 and p16. AntimiR-1468-3p antagonized transforming growth factor β1 (TGF-β1)-induced collagen deposition and metabolic activity. Mechanistically, mimic-1468-3p enhanced p38 phosphorylation, while antimiR-1468-3p decreased TGF-β1-induced p38 activation and abolished p38-induced collagen deposition. RNA sequencing analysis, a computational prediction model, and qPCR analysis identified dual-specificity phosphatases (DUSPs) as miR-1468-3p target genes, and regulation of DUSP1 by miR-1468-3p was confirmed with a dual-luciferase reporter assay. In conclusion, miR-1468-3p promotes cardiac fibrosis by enhancing TGF-β1-p38 signaling. Targeting miR-1468-3p in the older population may be of therapeutic interest to reduce cardiac fibrosis.
非编码微小RNA（miRNA）是基因表达的强大调节因子，在心血管病理生理学中起关键作用。本研究的目的是鉴定调节心脏纤维化的miRNA。对年龄匹配的对照受试者以及患有原发性心肌纤维化（PMF）的心脏性猝死（SCD）受害者的心脏样本进行miRNA分析。患有PMF的老年SCD受害者和健康老年人心脏中miR-1468-3p表达增加。在人心脏成纤维细胞中进行的体外研究表明，提高miR-1468-3p水平可诱导胶原蛋白沉积和细胞代谢活性，并增强胶原蛋白1、结缔组织生长因子和骨膜蛋白的表达。此外，miR-1468-3p通过增加衰老相关β-半乳糖苷酶活性以及p53和p16的表达来促进细胞衰老。抗miR-1468-3p可拮抗转化生长因子β1（TGF-β1）诱导的胶原蛋白沉积和代谢活性。机制上，模拟物-1468-3p增强p38磷酸化，而抗miR-1468-3p降低TGF-β1诱导的p38激活并消除p38诱导的胶原蛋白沉积。RNA测序分析、计算预测模型和qPCR分析确定双特异性磷酸酶（DUSP）为miR-1468-3p的靶基因，双荧光素酶报告基因检测证实了miR-1468-3p对DUSP1的调节作用。总之，miR-1468-3p通过增强TGF-β1-p38信号传导促进心脏纤维化。在老年人群中靶向miR-1468-3p可能对减少心脏纤维化具有治疗意义。
