Sacubitrilat reduces pro-arrhythmogenic sarcoplasmic reticulum Ca2+ leak in human ventricular cardiomyocytes of patients with end-stage heart failure

TY - JOUR

T1 - Sacubitrilat reduces pro-arrhythmogenic sarcoplasmic reticulum Ca2+ leak in human ventricular cardiomyocytes of patients with end-stage heart failure

AU - Eiringhaus, Jörg

AU - Wünsche, Christoph M

AU - Tirilomis, Petros

AU - Herting, Jonas

AU - Bork, Nadja

AU - Nikolaev, Viacheslav O

AU - Hasenfuss, Gerd

AU - Sossalla, Samuel

AU - Fischer, Thomas H

N1 - © 2020 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

PY - 2020/10

Y1 - 2020/10

N2 - AIMS: Inhibition of neprilysin and angiotensin II receptor by sacubitril/valsartan (Val) (LCZ696) reduces mortality in heart failure (HF) patients compared with sole inhibition of renin-angiotensin system. Beneficial effects of increased natriuretic peptide levels upon neprilysin inhibition have been proposed, whereas direct effects of sacubitrilat (Sac) (LBQ657) on myocardial Ca2+ cycling remain elusive.METHODS AND RESULTS: Confocal microscopy (Fluo-4 AM) was used to investigate pro-arrhythmogenic sarcoplasmic reticulum (SR) Ca2+ leak in freshly isolated murine and human ventricular cardiomyocytes (CMs) upon Sac (40 μmol/L)/Val (13 μmol/L) treatment. The concentrations of Sac and Val equalled plasma concentrations of LCZ696 treatment used in PARADIGM-HF trial. Epifluorescence microscopy measurements (Fura-2 AM) were performed to investigate effects on systolic Ca2+ release, SR Ca2+ load, and Ca2+ -transient kinetics in freshly isolated murine ventricular CMs. The impact of Sac on myocardial contractility was evaluated using in toto-isolated, isometrically twitching ventricular trabeculae from human hearts with end-stage HF. Under basal conditions, the combination of Sac/Val did not influence diastolic Ca2+ -spark frequency (CaSpF) nor pro-arrhythmogenic SR Ca2 leak in isolated murine ventricular CMs (n CMs/hearts = 80/7 vs. 100/7, P = 0.91/0.99). In contrast, Sac/Val treatment reduced CaSpF by 35 ± 9% and SR Ca2+ leak by 45 ± 9% in CMs put under catecholaminergic stress (isoproterenol 30 nmol/L, n = 81/7 vs. 62/7, P < 0.001 each). This could be attributed to Sac, as sole Sac treatment also reduced both parameters by similar degrees (reduction of CaSpF by 57 ± 7% and SR Ca2+ leak by 76 ± 5%; n = 101/4 vs. 108/4, P < 0.01 each), whereas sole Val treatment did not. Systolic Ca2+ release, SR Ca2+ load, and Ca2+ -transient kinetics including SERCA activity (kSERCA ) were not compromised by Sac in isolated murine CMs (n = 41/6 vs. 39/6). Importantly, the combination of Sac/Val and Sac alone also reduced diastolic CaSpF and SR Ca2+ leak (reduction by 74 ± 7%) in human left ventricular CMs from patients with end-stage HF (n = 71/8 vs. 78/8, P < 0.05 each). Myocardial contractility of human ventricular trabeculae was not acutely affected by Sac treatment as the developed force remained unchanged over a time course of 30 min (n trabeculae/hearts = 3/3 vs. 4/3).CONCLUSION: This study demonstrates that neprilysin inhibitor Sac directly improves Ca2+ homeostasis in human end-stage HF by reducing pro-arrhythmogenic SR Ca2+ leak without acutely affecting systolic Ca2+ release and inotropy. These effects might contribute to the mortality benefits observed in the PARADIGM-HF trial.

AB - AIMS: Inhibition of neprilysin and angiotensin II receptor by sacubitril/valsartan (Val) (LCZ696) reduces mortality in heart failure (HF) patients compared with sole inhibition of renin-angiotensin system. Beneficial effects of increased natriuretic peptide levels upon neprilysin inhibition have been proposed, whereas direct effects of sacubitrilat (Sac) (LBQ657) on myocardial Ca2+ cycling remain elusive.METHODS AND RESULTS: Confocal microscopy (Fluo-4 AM) was used to investigate pro-arrhythmogenic sarcoplasmic reticulum (SR) Ca2+ leak in freshly isolated murine and human ventricular cardiomyocytes (CMs) upon Sac (40 μmol/L)/Val (13 μmol/L) treatment. The concentrations of Sac and Val equalled plasma concentrations of LCZ696 treatment used in PARADIGM-HF trial. Epifluorescence microscopy measurements (Fura-2 AM) were performed to investigate effects on systolic Ca2+ release, SR Ca2+ load, and Ca2+ -transient kinetics in freshly isolated murine ventricular CMs. The impact of Sac on myocardial contractility was evaluated using in toto-isolated, isometrically twitching ventricular trabeculae from human hearts with end-stage HF. Under basal conditions, the combination of Sac/Val did not influence diastolic Ca2+ -spark frequency (CaSpF) nor pro-arrhythmogenic SR Ca2 leak in isolated murine ventricular CMs (n CMs/hearts = 80/7 vs. 100/7, P = 0.91/0.99). In contrast, Sac/Val treatment reduced CaSpF by 35 ± 9% and SR Ca2+ leak by 45 ± 9% in CMs put under catecholaminergic stress (isoproterenol 30 nmol/L, n = 81/7 vs. 62/7, P < 0.001 each). This could be attributed to Sac, as sole Sac treatment also reduced both parameters by similar degrees (reduction of CaSpF by 57 ± 7% and SR Ca2+ leak by 76 ± 5%; n = 101/4 vs. 108/4, P < 0.01 each), whereas sole Val treatment did not. Systolic Ca2+ release, SR Ca2+ load, and Ca2+ -transient kinetics including SERCA activity (kSERCA ) were not compromised by Sac in isolated murine CMs (n = 41/6 vs. 39/6). Importantly, the combination of Sac/Val and Sac alone also reduced diastolic CaSpF and SR Ca2+ leak (reduction by 74 ± 7%) in human left ventricular CMs from patients with end-stage HF (n = 71/8 vs. 78/8, P < 0.05 each). Myocardial contractility of human ventricular trabeculae was not acutely affected by Sac treatment as the developed force remained unchanged over a time course of 30 min (n trabeculae/hearts = 3/3 vs. 4/3).CONCLUSION: This study demonstrates that neprilysin inhibitor Sac directly improves Ca2+ homeostasis in human end-stage HF by reducing pro-arrhythmogenic SR Ca2+ leak without acutely affecting systolic Ca2+ release and inotropy. These effects might contribute to the mortality benefits observed in the PARADIGM-HF trial.

U2 - 10.1002/ehf2.12918

DO - 10.1002/ehf2.12918

M3 - SCORING: Journal article

C2 - 32710603

VL - 7

SP - 2992

EP - 3002

JO - ESC HEART FAIL

JF - ESC HEART FAIL

SN - 2055-5822

IS - 5

ER -