FNDC5 and heart disorder: As a key energy sensor to maintain energy balance and mitochondrial hemostasis (131), AMPK mediated the effect of FNDC5/irisin on mitophagy, oxidative stress, and mitochondrial biogenesis, thereby improving myocardial hypertrophy, myocardial infarction, atherosclerosis, and other cardiac diseases, which reflecting the protection of regular exercise on cardiac health.