Frontiers Pichia pastoris secreted peptides crossing the blood brain barrier and DSIP fusion peptide efficacy in PCPA induced insomnia mouse models Is DSIP Delta Sleep Inducing Peptide Safety?_Chemicalbook DSIP (Delta Sleep Inducing Peptide) is a synthetic nonapeptide originally isolated and studied for its association with neuroregulatory signaling systems. It is evaluated in controlled research environments for its interaction with central nervous DSIP Peptide for Sleep LIVV Natural