Houria Daimi1, Estefania Lozano-Velasco2, Amel Haj Khelil3, Jemni B E Chibani3, Adriana Barana4, Irene Amorós4, Marta González de la Fuente4, Ricardo Caballero4, Amelia Aranega2, Diego Franco5. 1. Department of Experimental Biology, University of Jaén, Jáen, Spain; Biochemistry and Molecular Biology Laboratory, Faculty of Pharmacy, University of Monastir, Monastir, Tunisia. 2. Department of Experimental Biology, University of Jaén, Jáen, Spain. 3. Biochemistry and Molecular Biology Laboratory, Faculty of Pharmacy, University of Monastir, Monastir, Tunisia. 4. Department of Pharmacology, Faculty of Medicine, Complutense University of Madrid, Madrid, Spain. 5. Department of Experimental Biology, University of Jaén, Jáen, Spain. Electronic address: dfranco@ujaen.es.
Abstract
BACKGROUND: The human cardiac action potential in atrial and ventricular cells is initiated by a fast-activating, fast-inactivating sodium current generated by the SCN5A/Nav1.5 channel in association with its β1/SCN1B subunit. The role of Nav1.5 in the etiology of many cardiac diseases strongly suggests that proper regulation of cell biology and function of the channel is critical for normal cardiac function. Hence, numerous recent studies have focused on the regulatory mechanisms of Nav1.5 biosynthetic and degradation processes as well as its subcellular localization. OBJECTIVE: The purpose of this study was to investigate the role of microRNAs in the Scn5a/Nav1.5 posttranscriptional regulation. METHODS: Quantitative polymerase chain reaction, immunohistochemical and electrophysiological measurements of distinct microRNA gain-of-function experiments in cardiomyocytes for the assessment of Scn5a expression. RESULTS: Functional studies of HL-1 cardiomyocytes and luciferase assays in fibroblasts demonstrate that Scn5a is directly (miR-98, miR-106, miR-200, and miR-219) and indirectly (miR-125 and miR-153) regulated by multiple microRNAs displaying distinct time-dependent profiles. Cotransfection experiments demonstrated that miR-219 and miR-200 have independent opposite effects on Scn5a expression modulation. Of all the microRNAs studied, only miR-219 increases Scn5a expression levels, leading to altered contraction rhythm of HL-1 cardiomyocytes. Electrophysiological analyses in HL-1 cells revealed that miR-219 increases the sodium current. In vivo administration of miR-219 does not alter normal cardiac rhythm, but abolishes some of the effects of flecainide intoxication in mice, particularly QRS prolongation. CONCLUSION: This study demonstrates the involvement of multiple microRNAs in the regulation of Scn5a. Particularly, miR-219 increases Scn5a/Nav1.5 transcript and protein expression. Our data suggest that microRNAs, such as miR-219, constitute a promising therapeutical tool to treat sodium cardiac arrhythmias.
BACKGROUND: The human cardiac action potential in atrial and ventricular cells is initiated by a fast-activating, fast-inactivating sodium current generated by the SCN5A/Nav1.5 channel in association with its β1/SCN1B subunit. The role of Nav1.5 in the etiology of many cardiac diseases strongly suggests that proper regulation of cell biology and function of the channel is critical for normal cardiac function. Hence, numerous recent studies have focused on the regulatory mechanisms of Nav1.5 biosynthetic and degradation processes as well as its subcellular localization. OBJECTIVE: The purpose of this study was to investigate the role of microRNAs in the Scn5a/Nav1.5 posttranscriptional regulation. METHODS: Quantitative polymerase chain reaction, immunohistochemical and electrophysiological measurements of distinct microRNA gain-of-function experiments in cardiomyocytes for the assessment of Scn5a expression. RESULTS: Functional studies of HL-1 cardiomyocytes and luciferase assays in fibroblasts demonstrate that Scn5a is directly (miR-98, miR-106, miR-200, and miR-219) and indirectly (miR-125 and miR-153) regulated by multiple microRNAs displaying distinct time-dependent profiles. Cotransfection experiments demonstrated that miR-219 and miR-200 have independent opposite effects on Scn5a expression modulation. Of all the microRNAs studied, only miR-219 increases Scn5a expression levels, leading to altered contraction rhythm of HL-1 cardiomyocytes. Electrophysiological analyses in HL-1 cells revealed that miR-219 increases the sodium current. In vivo administration of miR-219 does not alter normal cardiac rhythm, but abolishes some of the effects of flecainide intoxication in mice, particularly QRS prolongation. CONCLUSION: This study demonstrates the involvement of multiple microRNAs in the regulation of Scn5a. Particularly, miR-219 increases Scn5a/Nav1.5 transcript and protein expression. Our data suggest that microRNAs, such as miR-219, constitute a promising therapeutical tool to treat sodiumcardiac arrhythmias.
Authors: Xiaoming Zhang; Jin-Young Yoon; Michael Morley; Jared M McLendon; Kranti A Mapuskar; Rebecca Gutmann; Haider Mehdi; Heather L Bloom; Samuel C Dudley; Patrick T Ellinor; Alaa A Shalaby; Raul Weiss; W H Wilson Tang; Christine S Moravec; Madhurmeet Singh; Anne L Taylor; Clyde W Yancy; Arthur M Feldman; Dennis M McNamara; Kaikobad Irani; Douglas R Spitz; Patrick Breheny; Kenneth B Margulies; Barry London; Ryan L Boudreau Journal: J Clin Invest Date: 2018-02-19 Impact factor: 14.808
Authors: Estefanía Lozano-Velasco; Rosemary Wangensteen; Andrés Quesada; Carlos Garcia-Padilla; Julia A Osorio; María Dolores Ruiz-Torres; Amelia Aranega; Diego Franco Journal: PLoS One Date: 2017-12-01 Impact factor: 3.240