2026-04-13T02:29:39Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1970832025-12-04T21:15:14Zcom_2072_1057col_2072_478781col_2072_478917

00925njm 22002777a 4500 dc Martínez-Mármol, Ramón author David, Miren author Sanches, Rosario author Roura-Ferrer, Meritxell author Villalonga, Núria author Sorianello, Eleonora author Webb, Susan M. author Zorzano Olarte, Antonio author Gumà i Garcia, Anna Maria author Valenzuela, Carmen author Felipe Campo, Antonio author 2023-04-21T07:56:28Z 2023-04-21T07:56:28Z 2007-12-01 2023-04-21T07:56:28Z Objective: Cellular cardiomyoplasty using skeletal myoblasts is a promising therapy for myocardial infarct repair. Once transplanted, myoblasts grow, differentiate and adapt their electrophysiological properties towards more cardiac-like phenotypes. Voltage-dependent Na + channels (Na v ) are the main proteins involved in the propagation of the cardiac action potential, and their phenotype affects cardiac performance. Therefore, we examined the expression of Na v during proliferation and differentiation in skeletal myocytes. Methods and results: We used the rat neonatal skeletal myocyte cell line L6E9. Proliferation of L6E9 cells induced Na v 1.4 and Na v 1.5, although neither protein has an apparent role in cell growth. During myogenesis, Na v1.5 was largely induced. Electrophysiological and pharmacological properties, as well as mRNA expression, indicate that cardiac-type Na v1.5 accounts for almost 90% of the Na + current in myotubes. Unlike in proliferation, this protein plays a pivotal role in myogenesis. The adoption of a cardiac-like phenotype is further supported by the increase in Nav 1.5 colocalization in caveolae. Finally, we demonstrate that the treatment of myoblasts with neuregulin further increased Na v 1.5 in skeletal myocytes. Conclusion: Our results indicate that skeletal myotubes adopt a cardiac-like phenotype in cell culture conditions and that the expression of Na v1.5 acts as an underlying molecular mechanism. Canals iònics Miogènesi Malalties del cor Biologia del desenvolupament Ion channels Myogenesis Heart diseases Developmental biology Voltage-dependent Na+ channel phenotype changes in myoblasts. Consequences for cardiac repair