Peptide Database

Pentapeptide-18

Leuphasyl is a pentapeptide that acts as an enkephalin analog, binding to δ-opioid receptors on muscle cells and neuronal cells to modulate acetylcholine release and reduce muscle contraction. Often combined with Argireline in cosmetic formulations for a synergistic anti-wrinkle effect, studies show the combination outperforms either compound alone in reducing crow's feet and forehead lines.

Afamelanotide · Scenesse

Melanotan I (afamelanotide) is a linear synthetic α-MSH analog with higher selectivity for MC1R than MT-II. FDA-approved as Scenesse for erythropoietic protoporphyria (EPP), where it reduces phototoxic pain by enhancing melanin production and UV protection. Research explores broader applications in vitiligo, polymorphous light eruption, and other photosensitive disorders.

MT-II · MT2

Melanotan II is a cyclic synthetic analog of α-MSH that non-selectively activates melanocortin receptors (MC1R–MC5R). It induces skin tanning (via MC1R), erectile function (via MC4R), and sexual arousal while also suppressing appetite. It was the precursor compound from which PT-141 was developed. Research continues despite regulatory concerns due to its broad receptor activity profile.

Alpha-Melanocyte-Stimulating Hormone · α-Melanotropin

α-MSH is an endogenous 13-amino-acid peptide derived from POMC (pro-opiomelanocortin). It activates MC1R to stimulate melanin production in skin, MC4R to suppress appetite and regulate energy expenditure, and MC3R/MC1R to exert potent anti-inflammatory effects. It is the parent compound from which many synthetic melanocortin analogs (Melanotan I, II, PT-141, KPV) were derived and remains a cornerstone of melanocortin pharmacology research.