ANPEP and neurodegenerative disease: These protective effects of APN are exerted through binding of APN to its receptors, AdipoR1 and AdipoR2,88 in which a signaling cascade involving AMPK and peroxisome proliferator-activated receptor-α is activated.89 Since APN receptors are abundant in the nervous system,88 activation of APN signaling may also be beneficial for treating neurodegenerative diseases (Fig. 3a).