Peptable

Comparison

Melanotan I vs Semax

Function

While Melanotan I is approved in some regions for prevention of phototoxicity in erythropoietic protoporphyria and is studied as a skin-darkening, photoprotective peptide3444, 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 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, 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 I

Melanocortin-1 receptor (MC1R) 344481

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 I

Synthetic analog of human α-MSH derived from POMC34448190

Semax

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

Gene

Melanotan I

POMC

Semax

POMC

Summary

Melanotan I and Semax are noticeably different, with limited direct overlap in their usual biological context. Their typical research and application settings separate fairly clearly: Melanotan I is more often discussed in the realm of Dermatology and aesthetics, whereas Semax is more often associated with the realm of Neurology and brain health and Ophthalmology. They also influence different molecular systems, with Melanotan I 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 I incorporates d-amino acid substitution features that are not part of Semax.

Related articles

No related articles are linked to these peptides yet.

Sources

34Melanotan I (Afamelanotide): Research Profile - PeptideJournal, https://www.peptidejournal.org/peptides/melanotan-i-research-profile
44Melanotan I: properties, applications and references, https://www.benchchem.com/zh/product/b1666627
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