Acetyl tetrapeptide-5
is used in cosmetic eye formulations to decrease puffiness, eye bags, and dark circles by reducing edema and protecting proteins such as SOD from glycation
Alanine
Ala / A · hydrophobic residue · neutral charge
AOD-9604
is studied as an anti-obesity peptide that can reduce weight gain and increase fat oxidation in obese animal models with generally neutral effects on IGF-1 and glucose metabolism in early human trials
Arginine
Arg / R · basic residue · positive charge
Argireline
is a topical cosmetic peptide reported to decrease dynamic wrinkles by partially mimicking the mechanism of botulinum toxin in a non-invasive manner
Asparagine
Asn / N · polar residue · neutral charge
Aspartic acid
Asp / D · acidic residue · negative charge
BPC-157
is investigated for accelerating healing of gastrointestinal mucosa, tendons, ligaments, bone, and nervous tissue in preclinical models, with anti-inflammatory and pro-angiogenic effects
Comparison
While Dulaglutide is a once-weekly GLP-1RA for type 2 diabetes that lowers HbA1c and body weight by enhancing glucose-dependent insulin secretion and reducing appetite6668, Melanotan I is approved in some regions for prevention of phototoxicity in erythropoietic protoporphyria and is studied as a skin-darkening, photoprotective peptide3444.
While Dulaglutide works as a recombinant fusion protein consisting of two disulfide-linked GLP-1(7–37) analogs each covalently fused via a linker to an IgG4 Fc fragment, yielding a large, long-acting GLP-1 receptor agonist protected from DPP-4 degradation66, Melanotan I is a linear 13-amino-acid analog of α-MSH (afamelanotide) that selectively activates MC1R on melanocytes, increasing eumelanin synthesis and providing photoprotection3444.
Dulaglutide
GCG
Melanotan I
POMC
Both peptides fall into a similar broad context as Hormone peptides, although the details of how they are used and discussed still diverge. Their typical research and application settings separate fairly clearly: Dulaglutide is more often discussed in the realm of Metabolic and endocrine, whereas Melanotan I is more often associated with the realm of Dermatology and aesthetics. Both appear to work through Receptor agonist, but the functional emphasis still separates, with Dulaglutide leaning toward Metabolic regulation and Melanotan I leaning toward Melanogenesis modulation. Dulaglutide has a more engineered peptide origin, while Melanotan I is closer to synthetic analog background and their development context also differs, with Dulaglutide approved while Melanotan I is approved for Research use only. Dulaglutide takes the form of a peptide conjugate, whereas Melanotan I is closer to a linear peptide, Melanotan I incorporates d-amino acid substitution features that are not part of Dulaglutide; while their sequence patterns also diverge, with Dulaglutide showing alpha-helical domain features and Melanotan I showing protein-mimetic sequence features.