Interestingly, both VIP and SST were reported to exert protective effects in neurodegenerative diseases, including Alzheimer's disease and PD through inhibiting the microglial activation and expression of the cytotoxic mediators, such as TNF-α, IL-1β, and prostaglandin E2 [21, 29, 30]. This evidence concerns the gene SST and early-onset autosomal dominant Alzheimer disease.