INS and Atrophy: In addition, DEPP1 mRNA is induced after insulin or nutrient deprivation, fasting, or H2O2 through the FOXO1/3 transcription factors and is necessary for FOXO3-mediated autophagy.24,70–72 FOXO activation is necessary and sufficient to induce fasting-mediated skeletal and cardiac muscle autophagy and atrophy.73–76 Because chronic exposure to high altitude leads to hypoxia-induced muscle wasting, it will be important to learn whether DEPP1 acts as a muscle atrophy–related factor.