However, more data is showing that improving cognitive function is very important for functional recovery and quality of life.14,15 APN is a very active adipocyte secretory factor that combines with receptors AdipoR1 and R2 to exert its biological functions.16–18 Previous studies that have found that neurodegenerative diseases, cardiovascular diseases, hypertension, diabetes, abnormal lipid metabolism, obesity, and other diseases are closely related to APN levels.19–21. Here, ANPEP is linked to diabetes mellitus.