Abstract 15205: miR-132 Inhibition Improves Myocardial Strain in a Large Animal Model of Chronic Adverse Remodeling

Abstract

Background: MicroRNAs (miRNAs) are transcriptional regulators and essential drivers of heart failure (HF). The miR-132 is necessary and sufficient to progress adverse cardiac remodeling. The strong effects are exhibited by, amongst others, cardiomyocyte hypertrophy and calcium signaling impairment. Treatments directly targeting the roots of the disease are scarce, but miR-132 inhibition by CDR132L, a rationally designed synthetic oligonucleotide, significantly improves cardiac dysfunction in HF early after myocardial infarction (MI). Rational: The aim of the current study was to gain further data on myocardial function and efficacy of CDR132L by analyzing left ventricular (LV) and atrial (LA) wall motion by serial cardiac magnetic resonance (cMRI) strain imaging in a clinically relevant large animal (pig) model of chronic HF. Methods and Results: Mangalica pigs (n=15) were randomized 1-month post-MI, initiated by left anterior descending artery occlusion followed by reperfusion as a chronic model of post-MI HF. Animals received CDR132L over 5 months by monthly intravenous treatments with 5 mg/kg. LV and LA strain parameters were deteriorated after MI over time but significantly ameliorated by CDR132L treatment, compared to placebo. Strain parameters showed significant correlations with pharmacodynamic measures such as left-ventricular ejection fraction, NT-proBNP and cardiac interstitial fibrosis in remodeling hearts 6 months post-MI. Conclusions: LV and LA motion and contractility were improved by repeated dosing of CDR132L with monthly frequency in a large animal model of chronic post-MI HF. The results highlight the translational value and usability of MRI-based cardiac strain imaging in HF drug development and support further clinical development of CDR132L.