Neuropeptides derived fromVGF (nerve growth factor inducible) regulate the neuronal firing rate,40,41 and VGF is upregulated during memory and learning activities.40,42 VGF gene expression is decreased in AD brains,43 and overexpression of VGF in the 5xFAD mouse model of ADresults in improved memory functions;44 these findings indicate a role for VGF in memory functions thatis compromised in AD. This evidence concerns the gene VGF and Alzheimer disease.