Explore the vast range of titles available.

An interplay between Ca 2+ /calmodulin-dependent protein kinase IIδc (CaMKIIδc) and late Na + current (I NaL ) is known to induce arrhythmias in the failing heart. Here, we elucidate the role of the sodium channel isoform Na V 1.8 for CaMKIIδc-dependent proarrhythmia. In a CRISPR-Cas9-generated human iPSC-cardiomyocyte homozygous knock-out of Na V 1.8, we demonstrate that Na V 1.8 contributes to I NaL formation. In addition, we reveal a direct interaction between Na V 1.8 and CaMKIIδc in cardiomyocytes isolated from patients with heart failure (HF). Using specific blockers of Na V 1.8 and CaMKIIδc, we show that Na V 1.8-driven I NaL is CaMKIIδc-dependent and that Na V 1.8-inhibtion reduces diastolic SR-Ca 2+ leak in human failing cardiomyocytes. Moreover, increased mortality of CaMKIIδc-overexpressing HF mice is reduced when a Na V 1.8 knock-out is introduced. Cellular and in vivo experiments reveal reduced ventricular arrhythmias without changes in HF progression. Our work therefore identifies a proarrhythmic CaMKIIδc downstream target which may constitute a prognostic and antiarrhythmic strategy. In heart failure, increased CaMKII activity is decisively involved in arrhythmia formation. Here, the authors introduce the neuronal sodium channel Na V 1.8 as a CaMKII downstream target as its specific knock-out reduces arrhythmias and improves survival in a CaMKII-overexpressing mouse model.

An interplay between Ca /calmodulin-dependent protein kinase IIδc (CaMKIIδc) and late Na current (I ) is known to induce arrhythmias in the failing heart. Here, we elucidate the role of the sodium channel isoform Na 1.8 for CaMKIIδc-dependent proarrhythmia. In a CRISPR-Cas9-generated human iPSC-cardiomyocyte homozygous knock-out of Na 1.8, we demonstrate that Na 1.8 contributes to I formation. In addition, we reveal a direct interaction between Na 1.8 and CaMKIIδc in cardiomyocytes isolated from patients with heart failure (HF). Using specific blockers of Na 1.8 and CaMKIIδc, we show that Na 1.8-driven I is CaMKIIδc-dependent and that Na 1.8-inhibtion reduces diastolic SR-Ca leak in human failing cardiomyocytes. Moreover, increased mortality of CaMKIIδc-overexpressing HF mice is reduced when a Na 1.8 knock-out is introduced. Cellular and in vivo experiments reveal reduced ventricular arrhythmias without changes in HF progression. Our work therefore identifies a proarrhythmic CaMKIIδc downstream target which may constitute a prognostic and antiarrhythmic strategy.