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, Sermorelin is used as a diagnostic agent for assessing GH secretory capacity and as a research tool or off-label therapy to increase endogenous GH in GH-deficient or age-related contexts1727.
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, Sermorelin is a synthetic 29-amino-acid peptide identical to the 1–29 N-terminal fragment of human GHRH that stimulates GH synthesis and secretion by binding pituitary GHRH receptors1727120.
Length and Sequence
Argireline is 6 amino acids long, whereas Sermorelin is longer as it has a length of 29 amino acids. Argireline is made up of a sequence of Glutamic acid, Glutamic acid, Methionine, Glutamine, Arginine, Arginine. Sermorelin is made up of a sequence of Tyrosine, Alanine, Aspartic acid, Alanine, Isoleucine, Phenylalanine, Threonine, Asparagine, Serine, Tyrosine, Arginine, Lysine, Valine, Leucine, Glycine, Glutamine, Leucine, Serine, Alanine, Arginine, Lysine, Leucine, Leucine, Glutamine, Aspartic acid, Isoleucine, Methionine, Serine, Arginine.