Comparison

Kisspeptin vs Semax

Function

While Kisspeptin is a key regulator of the hypothalamic–pituitary–gonadal axis, controlling puberty and fertility; kisspeptin-10 also inhibits trophoblast invasion and tumor metastasis in experimental models339199, 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 Kisspeptin works as a family of peptides (eg, kisspeptin-10, -13, -14, -54) derived from the KISS1 precursor that activate G-protein–coupled receptor KISS1R (GPR54), triggering GnRH release and regulating pubertal onset and reproductive axis activity339199, 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.

Length and Sequence

Kisspeptin is 10 amino acids long, whereas Semax is shorter as it has a length of 7 amino acids. Kisspeptin is made up of a sequence of Tyrosine, Asparagine, Tryptophan, Asparagine, Serine, Phenylalanine, Glycine, Leucine, Arginine, Tyrosine. Semax is made up of a sequence of Methionine, Glutamic acid, Histidine, Phenylalanine, Proline, Glycine, Proline.

Receptor

Kisspeptin

KISS1R (GPR54) kisspeptin receptor33919943

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

Kisspeptin

Endogenous human peptide products of the KISS1 gene9199

Semax

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

Gene

Kisspeptin

KISS1

Semax

POMC

Sources

70Kisspeptin-10, rat, https://pubchem.ncbi.nlm.nih.gov/compound/Kisspeptin-10_-rat
91Kisspeptin - Wikipedia, https://en.wikipedia.org/wiki/Kisspeptin
99Kisspeptin-1 - an overview, https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/kisspeptin-1
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