The multifaceted role of autophagy and mitophagy in cardiovascular health and disease.

The cardiovascular system, consisting of the heart and blood vessels, ensures delivery of oxygen and nutrient-rich blood throughout the whole body. The major cell types include cardiomyocytes, endothelial cells, and vascular smooth muscle cells. Dramatic consequences, sometimes with a deadly outcome, may arise when the activity of cardiovascular cells is compromised. The cardiomyocytes are terminally differentiated cells and thus do not normally regenerate. To sustain the high energy demand of the beating heart, the cardiomyocytes contain a high amount of energy producing mitochondria. Adaptation to metabolic demands is an integral part of cellular homeostasis and involves autophagy. Autophagy is an evolutionary conserved intracellular degradation pathway of cellular constituents. Mitophagy refers to selective degradation of damaged, and thus potentially harmful, mitochondria through autophagy. Both autophagy and mitophagy are widely implicated in physiological and pathological processes within cardiovascular cells. In this review, we highlight studies applying genetic modifications in mouse models to reveal the impact of autophagy and mitophagy on cardiovascular health and disease.