Abstract 14815: LncCM1 is an Aging-Regulated Anti-Apoptotic Long Non-Coding RNA in Cardiomyocytes That Augments Recovery From Acute Myocardial Infarction
Long non-coding RNAs (lncRNAs) contribute to both physiological and pathological processes in the heart. Aging is the major risk factor for cardiovascular disease, among others because individual cardiomyocytes undergo apoptosis. Here, we identify the lncRNA lncCM1 that is regulated during aging in cardiomyocytes and hypothesize that it has a protective effect on the myocardium. Comparison of RNA deep sequencing profiles of cardiomyocytes and other heart cell types from young and aged mouse hearts revealed 74 cardiomyocyte-enriched, aging-regulated lncRNAs. Silencing these 74 lncRNAs followed by a caspase activity assay identified lncCM1 as an anti-apoptotic lncRNA (n=3). Flow cytometry analysis of apoptosis using Annexin V/7-AAD stained, lncCM1-silenced cardiomyocytes confirmed these results (Annexin V+ after 24 h: 3.53 ± 0.60-fold induction, Annexin V+/7-AAD+ after 48 h: 4.2 ± 0.53-fold induction). LncCM1 is localized in the nucleus and its genomic locus and some sequence elements are conserved between mouse and human. Mechanistically, microarray analysis shows that lncCM1 may regulate alternative splicing. After acute myocardial infarction (AMI) in mice, lncCM1 is profoundly downregulated in the infarct (n=3, -11.50 ± 0.32-fold) and the border region (n=3, -4.31 ± 0.6-fold) and hypoxia exposure and DFO treatment in vitro also downregulate lncCM1 expression in mouse (n=3; hypoxia: -1.95 ± 0.06-fold; DFO: -2.08 ± 0.01-fold) and human (n=3; hypoxia: -1.2 ± 0.34-fold; DFO: -4 ± 0.05-fold) cardiomyocytes. Using an adeno-associated virus serotype 9 vector, we overexpressed lncCM1 in mice (n=3, 12.22 ± 4.81-fold, p < 0.05) to assess the therapeutic potential of lncCM1 augmentation after AMI in vivo. LncCM1 overexpressing mice showed a better recovery of the ejection fraction after AMI, as measured by echocardiography (n=6-9, ejection fraction: 1.7 ± 0.16-fold, wall motion score index: - 6.56 ± 1.3-fold). In summary, we identified the anti-apoptotic evolutionary conserved lncRNA lncCM1, which is downregulated by aging and hypoxia, as a pivotal regulator of cardiomyocyte apoptosis. Overexpression of lncCM1 has beneficial effects on AMI recovery.
Author Disclosures: D. Trembinski: None. D. Berghäuser: None. A. Fischer: None. J. Boeckel: None. S. Werfel: None. S. Engelhardt: None. S. Dimmeler: None. R.A. Boon: None.
- © 2016 by American Heart Association, Inc.