Function
While Argireline is a topical cosmetic peptide reported to decrease dynamic wrinkles by partially mimicking the mechanism of botulinum toxin in a non-invasive manner49, DSIP was originally described for inducing spindle and delta sleep activity when infused into the brain of rabbits; later studies report stress-modulating and endocrine effects, though its physiological role is still debated47.
Mechanism
While Argireline works as acetyl hexapeptide-8 (Ac-Glu-Glu-Met-Gln-Arg-Arg-NH2), a SNAP-25–mimetic peptide that competitively inhibits SNARE complex assembly, reducing acetylcholine release at neuromuscular junctions and attenuating facial muscle contraction4959, DSIP is an endogenous nonapeptide, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, with proposed neuromodulatory actions; it interacts with components of the MAPK cascade and may be related to glucocorticoid-induced leucine zipper (GILZ), but its precise biosynthetic origin remains unknown4757.
Length and Sequence
Argireline is 6 amino acids long, whereas DSIP is longer as it has a length of 9 amino acids. Argireline is made up of a sequence of Glutamic acid, Glutamic acid, Methionine, Glutamine, Arginine, Arginine. DSIP is made up of a sequence of Tryptophan, Alanine, Glycine, Glycine, Aspartic acid, Alanine, Serine, Glycine, Glutamic acid.