Among others, PACAP has potent neuroprotective effects in models of focal and global cerebral ischemia [23,25,26], retinal pathologies [27], neuronal toxicities [22], multiple sclerosis and other inflammatory conditions [28,29], as well as in models of neurodegenerative diseases like Parkinson’s disease, Alzheimer’s disease and amyotrophic lateral sclerosis [30,31,32,33]. Here, ADCYAP1 is linked to early-onset autosomal dominant Alzheimer disease.