Molecular Binding of Melanotan 1 and 2 Receptors

Both Melanotan 1 (MT1) and Melanotan 2 (MT2) are artificial analogs of the naturally occurring hormone a-melanocyte stimulating hormone (a-MSH). Studies suggest both peptides may activate various fascinating responses by binding to melanocortin receptors. Research suggests MT1 and MT2 may control melanin expression and, by extension, skin pigment. It is hardly surprising that questions about Melanotan 1 versus 2 are often asked, given how functionally similar they are. Even while Melanotan 1 and 2 have a lot of similarities, there are also several key distinctions between the two that are explored in this article.

Molecular Binding of Melanotan 1 and 2 Receptors

Melanotans 1 and 2 do not appear to be very selective as agonists of various melanocortin receptors. Studies suggest both peptides may exhibit a wide range of binding affinities for melanocortin receptors, including MC1R (melanocortin 1 receptor), MC3R, MC4R, and MC5R. It’s worth noting that neither has much affinity for MC2, which regulates adrenal gland hormone release.

Research suggests the main difference between Melanotan 1 and 2 is that it appears that MT2 may maintain a-MSH’s increased affinity for the MC4 receptor, whereas MT1 may lose this property. Researchers speculate the potential effects of Melanotan 1 on pigmentation are greater, but the potential effects of Melanotan 2 on reproductive functioning are greater.

The principal receptor interactions between Melanotans 1 and 2 aren’t the only thing that makes them distinct. For example, scientists hypothesize Melanotan 1 may have powerful action at the pancreatic islet cell-specific MC5 receptor. Stimulating the MC5R may improve fatty acid metabolism [i]. However, Melanotan 2 may have substantial effects on the MC3 receptor. Although the MC3 receptor is mostly a mystery, it has been linked to certain ASD-related behaviors [ii].

Before discovering Melanotan 1, scientists knew little about the signaling mechanism between melanocortin receptors and their targets. This illustrates how an unimportant finding may lead to deeper insights into basic aspects of physiology. As research progresses, scientists can better examine the intricacies of the melanocortin system because of the distinction between Melanotan 1 and Melanotan 2.

Comparing Melanotan I and II from an R&D Perspective

Studies on Melanotons 1 and 2 has taken quite diverse directions, reflective of the individual peptides’ hypothesized distinct melanocortin receptor binding affinities.

The University of Arizona is credited with developing Melanotan 1, which has been suggested through rigorous research study to potentially increase pigmentation by up to 75% and possibly reduce sunburn by up to 47% as seen in test models. These qualities initially led developers to believe that MT1 might effectively prevent laboratory test models from exhibiting the long-term consequences of UV damage [iii]. Several factors contributed to the failure of this attempt to employ Melanotan 1 in research, and the peptide has since been abandoned.

Bremelanotide, a synthetic version of Melanotan 2, has been developed as an additional compound with related potential. Bremelanotide was assumed to be an MT2 metabolite. Many research studies suggested that Bremelanotide peptide, an alleged metabolite of MT2, could be responsible for the compound’s positive properties in research trials. The realization that many of the problems that caused researchers to leave Melanotan 1 and 2 could be addressed with minor tweaks to the peptides sparked renewed interest in the compounds. Since this time, studies have observed the potential of MT1 action across 15 research studies of MT1, leading to almost 200 published articles [iv].

Buy Melanotan-1 or any other compounds mentioned in this article only if you are a licensed professional, scientist, academic, or professor. None of the compounds mentioned have been approved for human consumption. Therefore, they should only be employed in research studies conducted in contained laboratory settings.

References

[i] C. L. Møller et al., “Characterization of murine melanocortin receptors mediating adipocyte lipolysis and examination of signalling pathways involved,” Mol. Cell. Endocrinol., vol. 341, no. 1–2, pp. 9–17, Jul. 2011, doi: 10.1016/j.mce.2011.03.010.

[ii] E. Minakova et al., “Melanotan-II reverses autistic features in a maternal immune activation mouse model of autism,” PloS One, vol. 14, no. 1, p. e0210389, 2019, doi: 10.1371/journal.pone.0210389.

[iii] R. T. Dorr et al., “Effects of a superpotent melanotropic peptide in combination with solar UV radiation on tanning of the skin in human volunteers,” Arch. Dermatol., vol. 140, no. 7, pp. 827–835, Jul. 2004, doi: 10.1001/archderm.140.7.827.

[iv] “Pharmaceutical Technology,” Clinuvel. https://www.clinuvel.com/pharmaceutical-technology…