RT Journal Article
SR Electronic
T1 SNTA1 Gene Rescues Ion Channel Function in Cardiomyocytes Derived from Induced Pluripotent Stem Cells Reprogrammed from Muscular Dystrophy Patients with Arrhythmias
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2022.01.25.477696
DO 10.1101/2022.01.25.477696
A1 Eric N Jimenez-Vazquez
A1 Michael Arad
A1 Álvaro Macías
A1 Maria Linarejos Vera-Pedrosa
A1 Francisco M. Cruz-Uréndez
A1 Ashley J Cuttitta
A1 André Monteiro Da Rocha
A1 Todd J Herron
A1 Daniela Ponce-Balbuena
A1 Guadalupe Guerrero-Serna
A1 Ofer Binah
A1 Daniel E Michele
A1 José Jalife
YR 2022
UL http://biorxiv.org/content/early/2022/01/26/2022.01.25.477696.abstract
AB Patients with cardiomyopathy of Duchenne Muscular Dystrophy (DMD) are at risk of developing life-threatening arrhythmias, but the mechanisms are unknown. We aimed to determine the role of cardiac ion channels controlling cardiac excitability in the mechanisms of arrhythmias in DMD patients. To test whether cardiac dystrophin mutations lead to defective NaV1.5–Kir2.1 channelosomes and arrhythmias, we generated iPSC-CMs from two hemizygous DMD males, a heterozygous female, and two unrelated controls. Two Patients had abnormal ECGs with frequent runs of ventricular tachycardia. iPSC-CMs from all DMD patients showed abnormal action potential profiles, slowed conduction velocities, and reduced sodium (INa) and inward rectifier potassium (IK1) currents. Membrane NaV1.5 and Kir2.1 protein levels were reduced in hemizygous DMD iPSC-CMs but not in heterozygous iPSC-CMs. Remarkably, transfecting just one component of the dystrophin protein complex (α1-syntrophin) in hemizygous iPSC-CMs restored channelosome function, INa and IK1 densities and action potential profile. We provide the first demonstration that iPSC-CMs reprogrammed from skin fibroblasts of DMD patients with cardiomyopathy have a dysfunction of the NaV1.5-Kir2.1 channelosome, with consequent reduction of cardiac excitability and conduction. Altogether, iPSC-CMs from patients with DMD cardiomyopathy have a NaV1.5-Kir2.1 channelosome dysfunction, which can be rescued by the scaffolding protein α1-syntrophin to restore excitability.Competing Interest StatementThe authors have declared no competing interest.