Riduzione età-correlata del precondizionamento ischemico: Ruolo dell'attività fisica e della restrizione calorica

Ischemic preconditioning, the most powerful endogenous protective mechanism against cardiac ischemia-reperfusion injury, is reduced with aging. The mechanism responsible for the age-related reduction of ischemic preconditioning seems to be the reduction of norepinephrine release from cardiac adrenergic terminations in response to ischemic preconditioning stimulus. The age-related reduction of ischemic preconditioning is also evident in elderly patients: preinfarction angina, a clinical equivalent of ischemic preconditioning, reduces mortality in adult but not in elderly patients with acute myocardial infarction. Physical activity or caloric restriction are partially capable to preserve the cardioprotective effect of ischemic preconditioning in the aging heart. More importantly, physical activity and caloric restriction in tandem action completely preserve the protective mechanism of ischemic preconditioning. Accordingly, the protective mechanism of preinfarction angina is preserved in elderly patients with a high grade of physical activity or a low level of body-mass index. Thus, both physical activity and caloric restriction are confirmed as powerful anti-aging interventions capable to restore age-dependent reduction of a critical endogenous protective mechanism, such as ischemic preconditioning.