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, Thymosin Alpha-1 is clinically used in some countries as an immunomodulator for chronic hepatitis B/C and as an adjuvant in cancer therapy, enhancing cell-mediated immunity41487.
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, Thymosin Alpha-1 is a 28-amino-acid thymic peptide fragment of prothymosin alpha that activates dendritic cells and T cells primarily via TLR9/MyD88/NF-κB signaling, enhancing Th1 responses and NK-cell cytotoxicity414.
Length and Sequence
Argireline is 6 amino acids long, whereas Thymosin Alpha-1 is longer as it has a length of 28 amino acids. Argireline is made up of a sequence of Glutamic acid, Glutamic acid, Methionine, Glutamine, Arginine, Arginine. Thymosin Alpha-1 is made up of a sequence of Serine, Aspartic acid, Alanine, Alanine, Valine, Aspartic acid, Threonine, Serine, Serine, Glutamic acid, Isoleucine, Threonine, Threonine, Lysine, Aspartic acid, Leucine, Lysine, Glutamic acid, Lysine, Lysine, Glutamic acid, Valine, Valine, Glutamic acid, Glutamic acid, Alanine, Glutamic acid, Asparagine.