Views from within and beyond - Narratives of cardiac contractile dysfunction under senescence

Senesecence is associated with enhanced risk of cardiovascular diseases. It is generally considered that decline in growth hormones (such as insulin-like growth factor I), intrinsic myocardial and endothelial functions, as well as accumuation of reactive oxygen species with increased age may contribute to cardiovascular senescence. It is believed that heart function, especially cardiac reserve declines with advanced age. However, most experimental and clinical investigations on ventricluar function only included young or adult subjects and failed to address this important age issue in heart pathophysiology. Although senescent but otherwise healthy hearts may possess normal pumping function at the resting or non-stressed state, some aging-associated factors such as accumulation of reactive oxygen species and activation of selective stress signaling pathways may interact with certain risk factors and compromise overall cardiac function. The precise cause and progression of compromised cardiac function in the elderly remain controversial. This review will focus on senescene-related alterations in cardiac contractile function with a special emphasis on oxidative stress and activation of stress signaling.