Nutrient restriction preserves calcium cycling and mitochondrial function in cardiac myocytes during ischemia and reperfusion

Relative to controls, NR monolayers: (1) sustained Ca oscillations during longer periods of ischemia (19.2 ± 1.8 min vs 10.4 ± 1.4 min, p < 0.001); (2) had attenuated increases in Ca transient duration (CaD) and time decay constant (Tau) during ischemia; (3) had preserved conduction velocity (CV) during early reperfusion, leading to protection against reperfusion arrhythmias; (4) had minimal “rebound” decreased CaD and Tau during reperfusion; and (5) had no depolarization of Δψm during IR. NR attenuates IR arrhythmias via (1) stable calcium cycling and (2) prevention of Δψm depolarization during IR. Enhanced mitochondrial resistance to IR arrhythmias may play a role in NR-induced longevity prolongation.