Peptable

Comparison

Melanotan II vs Semax

Function

While Melanotan II is studied as a tanning and libido-enhancing agent; increases melanin production and can reduce food intake and modulate sexual arousal in animal models and humans3545, Semax is used clinically in Russia for ischemic stroke and cognitive disorders; in models it improves learning, protects dopaminergic neurons, and modulates stress responses without significant endocrine ACTH-like effects166174.

Mechanism

While Melanotan II works as a cyclic heptapeptide melanocortin analog (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2) that acts as a non-selective, high-potency agonist at MC1R, MC3R, MC4R, and MC5R, influencing pigmentation, appetite, and sexual behavior3545, Semax is a synthetic heptapeptide, Met-Glu-His-Phe-Pro-Gly-Pro (MEHFPGP), that is an analog of ACTH(4–10) with a Pro-Gly-Pro extension and exerts neurotrophic and neuroprotective actions partly via upregulation of BDNF and modulation of dopaminergic and glutamatergic systems40162165174.

Receptor

Melanotan II

Melanocortin receptors MC1R, MC3R, MC4R, and MC5R (non-selective agonist) 3545

Semax

Targets are not fully defined; interacts with melanocortin-related pathways and inhibits certain peptidases, but no single dominant receptor has been established174

Organism or Origin

Melanotan II

Synthetic analog of POMC-derived melanocortin peptides358190

Semax

Synthetic analog of human ACTH(4–10) derived from POMC1748190

Gene

Melanotan II

POMC

Semax

POMC

Summary

Both peptides fall into a similar broad context as Neuropeptides, although the details of how they are used and discussed still diverge. Their typical research and application settings separate fairly clearly: Melanotan II is more often discussed in the realm of Dermatology and aesthetics and Reproductive health, whereas Semax is more often associated with the realm of Neurology and brain health and Ophthalmology. They also influence different molecular systems, with Melanotan II tracking more closely to Melanocortin receptor while Semax centers more on GPCR receptor. Both are synthetic in origin and both are still best understood as being approved for Research use only. Melanotan II takes the form of a cyclic peptide, whereas Semax is closer to a linear peptide, while Melanotan II incorporates acetylation features that are not part of Semax.

Related articles

No related articles are linked to these peptides yet.

Sources

35What is melanotan II? - Creative Peptides, https://www.creative-peptides.com/resources/what-is-melanotan-ii-peptide.html
45[PDF] melanotan-II peptide structure and molecular formula - Benchchem, https://www.benchchem.com/pdf/melanotan_II_peptide_structure_and_molecular_formula.pdf
81Proopiomelanocortin (POMC), the ACTH/melanocortin precursor, is ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC2253185/
90alpha-Melanocyte stimulating hormone: production and degradation, https://pmc.ncbi.nlm.nih.gov/articles/PMC3936413/
40Semax ACTH(4-10) Analog Peptide ≥99% | VivePeptides, https://vivepeptides.com/product/semax/
81Proopiomelanocortin (POMC), the ACTH/melanocortin precursor, is ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC2253185/
90alpha-Melanocyte stimulating hormone: production and degradation, https://pmc.ncbi.nlm.nih.gov/articles/PMC3936413/
162Semax 0.1% 10 mg | SEMAX POLAND, https://semaxpolska.com/en/semax-01-10-mg/
166The neuroprotective effects of Semax in conditions ..., https://pubmed.ncbi.nlm.nih.gov/15341218/
170Semax, https://pubchem.ncbi.nlm.nih.gov/compound/Met-Glu-His-Phe-Pro-Gly-Pro
171Semax peptide - NovoPro Bioscience Inc., https://www.novoprolabs.com/p/acth4-10-317047.html
174Semax - Wikipedia, https://en.wikipedia.org/wiki/Semax