In this review, we showed that anorexigenic neuropeptides, such as melanocortins, CARTp, PrRP, NPFF, PACAP, CRH and THR and their analogs not only decrease body weight, lower blood glucose levels, or ameliorate lipid profiles, but also improve cognitive impairment and the hallmarks of AD-like pathology in preclinical models (Figure 2). Here, PRLH is linked to Alzheimer disease.