Generation of microRNA-378a-deficient hiPSC as a novel tool to study its role in human cardiomyocytes

• Published in: Journal of molecular and cellular cardiology Vol. 160; pp. 128 - 141
• Main Authors: Martyniak, Alicja, Andrysiak, Kalina, Motais, Benjamin, Coste, Solène, Podkalicka, Paulina, Ferdek, Paweł, Stępniewski, Jacek, Dulak, Józef
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.11.2021
• Subjects: Antagomirs - genetics; Calcium - metabolism; Calcium Signaling - genetics; Cardiomyocytes; Cardiomyopathies - complications; Cardiomyopathies - genetics; Cardiomyopathies - metabolism; Cell Differentiation - genetics; Cell Enlargement; Cell Size; CRISPR/Cas9; Duchenne muscular dystrophy; Dystrophin - genetics; Dystrophin - metabolism; Exons; Gene Deletion; HEK293 Cells; Human induced pluripotent stem cells; Humans; Induced Pluripotent Stem Cells - cytology; Induced Pluripotent Stem Cells - metabolism; microRNA-378a; MicroRNAs - genetics; MicroRNAs - metabolism; Muscular Dystrophy, Duchenne - blood; Muscular Dystrophy, Duchenne - complications; Muscular Dystrophy, Duchenne - genetics; Myocytes, Cardiac - cytology; Myocytes, Cardiac - metabolism; Receptor, IGF Type 1 - metabolism; Transfection; microRNA-378a; CRISPR/Cas9; hiPSC-CM; PGC1β; MEA; Cardiomyocytes; IGF1R; hiPSC; Duchenne muscular dystrophy; Human induced pluripotent stem cells; BMD; DMD; hESC; hESC-CM
• ISSN: 0022-2828; 1095-8584
• DOI: 10.1016/j.yjmcc.2021.07.007

microRNA-378a (miR-378a) is one of the most highly expressed microRNAs in the heart. However, its role in the human cardiac tissue has not been fully understood. It was observed that miR-378a protects cardiomyocytes from hypertrophic growth by regulation of IGF1R and the expression of downstream kinases. Increased levels of miR-378a were reported in the serum of Duchenne muscular dystrophy (DMD) patients and female carriers of DMD gene-associated mutations with developed cardiomyopathy. In order to shed more light on the role of miR-378a in human cardiomyocytes and its potential involvement in DMD-related cardiomyopathy, we generated two human induced pluripotent stem cell (hiPSC) models; one with deletion of miR-378a and the second one with deletion of DMD exon 50 leading to the DMD phenotype. Our results indicate that lack of miR-378a does not influence the pluripotency of hiPSC and their ability to differentiate into cardiomyocytes (hiPSC-CM). miR-378a-deficient hiPSC-CM exhibited, however, significantly bigger size compared to the isogenic control cells, indicating the role of this miRNA in the hypertrophic growth of human cardiomyocytes. In accordance, the level of NFATc3, phosphoAKT, phosphoERK and ERK was higher in these cells compared to the control counterparts. A similar effect was achieved by silencing miR-378a with antagomirs. Of note, the percentage of cells with nuclear localization of NFATc3 was higher in miR-378a-deficient hiPSC-CM. Analysis of electrophysiological properties and Ca2+ oscillations revealed the decrease in the spike slope velocity and lower frequency of calcium spikes in miR-378a-deficient hiPSC-CM. Interestingly, the level of miR-378a increased gradually during cardiac differentiation of hiPSC. Of note, it was low until day 15 in differentiating DMD-deficient hiPSC-CM and then rose to a similar level as in the isogenic control counterparts. In summary, our findings confirmed the utility of hiPSC-based models for deciphering the role of miR-378a in the control and diseased human cardiomyocytes. [Display omitted] •Lack of miR-378a does not influence the pluripotency of hiPSC and their ability for cardiac differentiation.•Expression of miR-378a increases during cardiac differentiation of human iPSC.•The deletion of miR-378a promotes hypertrophic growth of hiPSC-CM, associated with NFATc3 nuclear localization.•miR-378a-deficient hiPSC-CM demonstrate lower frequency of spontaneous calcium oscillations in comparison to control cells.