Pierluigi Lesizza1, Giulia Prosdocimo1, Valentina Martinelli1, Gianfranco Sinagra1, Serena Zacchigna1, Mauro Giacca2. 1. From the Molecular Medicine (P.L., G.P., V.M., M.G.) and Cardiovascular Biology (S.Z.) Laboratories, International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy; and Department of Medical, Surgical and Health Sciences, University of Trieste, Italy (P.L., G.S., S.Z., M.G.). 2. From the Molecular Medicine (P.L., G.P., V.M., M.G.) and Cardiovascular Biology (S.Z.) Laboratories, International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy; and Department of Medical, Surgical and Health Sciences, University of Trieste, Italy (P.L., G.S., S.Z., M.G.). giacca@icgeb.org.
Abstract
RATIONALE: Recent evidence indicates that a few human microRNAs (miRNAs), in particular hsa-miR-199a-3p and hsa-miR-590-3p, stimulate proliferation of cardiomyocytes and, once expressed in the mouse heart using viral vectors, induce cardiac regeneration after myocardial infarction. Viral vectors, however, are not devoid of safety issues and, more notably, drive expression of the encoded miRNAs for indefinite periods of time, which might not be desirable in light of human therapeutic application. OBJECTIVE: As an alternative to the use of viral vectors, we wanted to assess the efficacy of synthetic miRNA mimics in inducing myocardial repair after single intracardiac injection using synthetic lipid formulations. METHODS AND RESULTS: We comparatively analyzed the efficacy of different lipid formulations in delivering hsa-miR-199a-3p and hsa-miR-590-3p both in primary neonatal mouse cardiomyocytes and in vivo. We established a transfection protocol allowing persistence of these 2 mimics for at least 12 days after a single intracardiac injection, with minimal dispersion to other organs and long-term preservation of miRNA functional activity, as assessed by monitoring the expression of 2 mRNA targets. Administration of this synthetic formulation immediately after myocardial infarction in mice resulted in marked reduction of infarct size and persistent recovery of cardiac function. CONCLUSIONS: A single administration of synthetic miRNA-lipid formulations is sufficient to stimulate cardiac repair and restoration of cardiac function.
RATIONALE: Recent evidence indicates that a few human microRNAs (miRNAs), in particular hsa-miR-199a-3p and hsa-miR-590-3p, stimulate proliferation of cardiomyocytes and, once expressed in the mouse heart using viral vectors, induce cardiac regeneration after myocardial infarction. Viral vectors, however, are not devoid of safety issues and, more notably, drive expression of the encoded miRNAs for indefinite periods of time, which might not be desirable in light of human therapeutic application. OBJECTIVE: As an alternative to the use of viral vectors, we wanted to assess the efficacy of synthetic miRNA mimics in inducing myocardial repair after single intracardiac injection using synthetic lipid formulations. METHODS AND RESULTS: We comparatively analyzed the efficacy of different lipid formulations in delivering hsa-miR-199a-3p and hsa-miR-590-3p both in primary neonatal mouse cardiomyocytes and in vivo. We established a transfection protocol allowing persistence of these 2 mimics for at least 12 days after a single intracardiac injection, with minimal dispersion to other organs and long-term preservation of miRNA functional activity, as assessed by monitoring the expression of 2 mRNA targets. Administration of this synthetic formulation immediately after myocardial infarction in mice resulted in marked reduction of infarct size and persistent recovery of cardiac function. CONCLUSIONS: A single administration of synthetic miRNA-lipid formulations is sufficient to stimulate cardiac repair and restoration of cardiac function.
Authors: Joshua Mayourian; Delaine K Ceholski; Przemek A Gorski; Prabhu Mathiyalagan; Jack F Murphy; Sophia I Salazar; Francesca Stillitano; Joshua M Hare; Susmita Sahoo; Roger J Hajjar; Kevin D Costa Journal: Circ Res Date: 2018-02-15 Impact factor: 17.367