Semax

Semax

Clinical data
Trade names	Semax
Other names	L-Methionyl-L-α-glutamylhistidyl-L-phenylalanyl-L-prolylglycyl-L-proline, (Pro8,Gly9,Pro10)ACTH-(4-10)
ATC code	N06BX
Legal status
Legal status	US: Not FDA approved; unscheduled
Identifiers
IUPAC name (2S)-1-[2-{[(2S)-1-[(2S)-2-{[2-{[(2S)-2-{[(2S)-2-amino-4-methylsulfanylbutanoyl]amino}-4-carboxybutanoyl]amino}-3-(1H-imidazol-5-yl)propanoyl]amino}-3-phenylpropanoyl]pyrrolidine-2-carbonyl]amino}acetyl]pyrrolidine-2-carboxylic acid
CAS Number	80714-61-0 Y 4037-01-8
PubChem CID	122178
ChemSpider	108969
UNII	I5FAL2585H
CompTox Dashboard (EPA)	DTXSID601001439
Chemical and physical data
Formula	C37H51N9O10S
Molar mass	813.93 g·mol−1
3D model (JSmol)	Interactive image
SMILES O=C(N[C@@H](CCC(O)=O)C(N[C@@H](CC1=CNC=N1)C(N[C@@H](CC2=CC=CC=C2)C(N3[C@@H](CCC3)C(NCC(N4[C@@H](CCC4)C(O)=O)=O)=O)=O)=O)=O)[C@H](CCSC)N
InChI InChI=1S/C37H51N9O10S/c1-57-16-13-24(38)32(50)42-25(11-12-31(48)49)33(51)43-26(18-23-19-39-21-41-23)34(52)44-27(17-22-7-3-2-4-8-22)36(54)46-15-5-9-28(46)35(53)40-20-30(47)45-14-6-10-29(45)37(55)56/h2-4,7-8,19,21,24-29H,5-6,9-18,20,38H2,1H3,(H,39,41)(H,40,53)(H,42,50)(H,43,51)(H,44,52)(H,48,49)(H,55,56)/t24-,25-,26?,27-,28-,29-/m0/s1 Key:AFEHBIGDWIGTEH-CXFOGXNKSA-N

Semax is a medication which is used in Russia and Eastern Europe for the treatment of a broad range of conditions like brain trauma but predominantly for its claimed nootropic, neuroprotective, and neurorestorative effects.^[1]

The mechanism of action of Semax is unknown.^[2][3] It might interact with certain melanocortin receptors or inhibit enkephalinase enzymes.^[2][3] Chemically, Semax is a peptide and a synthetic analogue of a fragment of adrenocorticotropic hormone (ACTH).^[4][5]

Semax was first described by 1991.^[5] Although used as a prescription drug in Russia and Eastern Europe, Semax has not been evaluated, approved for use, or marketed in most other countries.^[6][7] The drug is widely sold by online vendors and used as a purported nootropic (cognitive enhancer).^[1][8]

Semax has undergone extensive study in Russia and is on the Russian List of Vital & Essential Drugs approved by the Russian Federation government on 7 December 2011.^[9] Medical uses for Semax include treatment of stroke, transient ischemic attack, memory and cognitive disorders, peptic ulcers, optic nerve disease, and to boost the immune system.^{[10][11][12][13]}

In animals, Semax rapidly elevates the levels and expression of brain-derived neurotrophic factor (BDNF) and its signaling receptor tropomyosin receptor kinase B (TrkB) in the hippocampus,^[14] and rapidly activates serotonergic and dopaminergic brain systems.^[15][16] Accordingly, it has been found to produce antidepressant-like and anxiolytic-like effects,^[17][18] attenuate the behavioral effects of exposure to chronic stress,^[17][18] and potentiate the locomotor activity produced by D-amphetamine.^[16][19] As such, it has been suggested that Semax may be effective in the treatment of depression.^[20]

Though the exact mechanism of action of Semax is unclear, there is evidence that it may act through melanocortin receptors. Specifically, there is a report of Semax competitively antagonizing the action of the melanocortin receptor full agonist α-melanocyte-stimulating hormone (α-MSH) at the MC₄ and MC₅ receptors in both in vitro and in vivo experimental conditions, indicating that it may act as an antagonist or partial agonist of these receptors.^[2] Semax did not antagonize α-MSH at the MC₃ receptor, though this receptor could still be a target of the drug.^[2] As for the MC₁ and MC₂ receptors, they were not assayed.^[2] In addition to actions at receptors, Semax, as well as a related peptide drug, Selank, have been found to inhibit enzymes involved in the degradation of enkephalins and other endogenous regulatory peptides (IC₅₀ = 10 μM), though the clinical significance of this property is uncertain.^[3]

As a peptide, Semax has poor oral bioavailability and hence is administered parenterally as a nasal spray or subcutaneous injection.

Semax is a heptapeptide and synthetic analogue of a fragment of adrenocorticotropic hormone (ACTH), ACTH (4-10), of the following amino acid sequence: Met-Glu-His-Phe-Pro-Gly-Pro (MEHFPGP in single-letter form).^[4]

Semax was first described in the scientific literature by 1991.^[5]

Semax is composed of seven amino acid residues: Met-Glu-His-Phe-Pro-Gly-Pro (MEHFPGP), which is reflected in the name - from an abbreviation of "seven amino acids"—in Russian: СЕМь АминоКиСлот—СЕМАКС.

Semax was developed, produced, and marketed by Peptogen in the Russian Federation with participation of the Institute of Molecular Genetics of the Russian Academy of Sciences.^{[citation needed]}

• Selank
• 9-Methyl-β-carboline (9-Me-BC)
• Bromantane
• List of Russian drugs