Melanotan 2 has been shown in studies to exhibit appetite suppressant, lipolytic, and libido-enhancing effects in addition to promoting skin tanning. Melanotan 2 has been researched extensively for use in protecting against the harmful effects of ultraviolet radiation from sunlight due to its melanogenesis-stimulating properties.
Melanotan 1 (also referred to as Afamelanotide) is a synthetic peptide variant of a peptide hormone, called alpha-Melanocyte stimulating hormone or MSH that is naturally produced in the body and is responsible for stimulating melanogenesis, a peptide process for pigmentation of the skin. Alpha-MSH activates certain melanocortin receptors in the process of exerting its effects. Indeed, MSH also exerts potent influence over lipid metabolism, appetite, and sexual libido via these melanocortin receptors. As a result, Melanotan-1 sunless skin tanning effects. While Melanotan 2 and PT-141 have been studied at length as a potential remedies for the treatment of sexual dysfunction, Melanotan-1 has been researched extensively for use in protecting against the harmful effects of ultraviolet radiation from sunlight due to its melanogenesis-stimulating properties.
Both Melanotan-1 and Melanotan 2 are analogs of the peptide hormone alpha-melanocyte stimulating hormone (α -MSH) that tend to induce skin tanning. Unlike Melanotan 1, Melanotan 2 has been shown to have aphrodisiac properties, the additional effect of increasing libido. Melanotan-1 is a non selective agonist of the melanocortin receptors (MC1R, MC3-5R). As an analogue of α -MSH, its mechanism of action is biomimicry of the natural mammalian tanning process.
A few synthetic analogues of α-MSH have been investigated for their apparent photoprotective effects against ultraviolet (UV) radiation from the sun, namely Melanotan (afamelanotide) and Melanotan II, referred to as Melanotan 2. Bremelanotide, another analogue of α-MSH similar to Melanotan 2, is currently under development for the treatment of sexual dysfunction. All of these melanotan peptides have significantly greater potencies than α-MSH, but with distinctive selectivity peptide profiles.