Furthermore, as an endogenous neurohormone, melatonin is inversely association with the occurrence of heart attacks and plays a key role in regulating MI/R injury, as it can exert cardiac protection not only by direct antioxidant effects or activating the cell membrane or nuclear receptors, which widely expressed in the heart, but also by adjusting the complex associated signaling pathways to regulate various physiological processes; for example, it can protect the heart against MI/R by inhibiting autophagosome formation via the AMPK/mTOR pathway [155] . The gene discussed is PRKAA2; the disease is myocardial infarction.