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 Melanotan I is approved in some regions for prevention of phototoxicity in erythropoietic protoporphyria and is studied as a skin-darkening, photoprotective peptide3444, PT-141 is FDA-approved for treatment of hypoactive sexual desire disorder in premenopausal women and is studied for sexual dysfunction in other populations, increasing sexual desire via CNS melanocortin pathways42101.
While Melanotan I works as a linear 13-amino-acid analog of α-MSH (afamelanotide) that selectively activates MC1R on melanocytes, increasing eumelanin synthesis and providing photoprotection3444, PT-141 is the synthetic melanocortin receptor agonist bremelanotide, an analog of α-MSH that activates central MC3R and MC4R to modulate neuronal circuits governing sexual desire and arousal3242101.
Melanotan I
POMC
PT-141
POMC
Melanotan I and PT-141 sit closest together within the Melanocortin family, which gives them a broadly related biological identity. Their typical research and application settings separate fairly clearly: Melanotan I is more often discussed in the realm of Dermatology and aesthetics, whereas PT-141 is more often associated with the realm of Reproductive health. They also influence different molecular systems, with Melanotan I tracking more closely to Melanocortin receptor while PT-141 centers more on GPCR receptor. Both are synthetic in origin and their development context also differs, with Melanotan I approved for Research use only while PT-141 is approved. Melanotan I takes the form of a linear peptide, whereas PT-141 is closer to a cyclic peptide, while Melanotan I carries d-amino acid substitution features, while PT-141 instead reflects acetylation changes.
No related articles are linked to these peptides yet.