What is Semax?
Semax is a seven-amino-acid peptide built on a fragment of the hormone ACTH. Here is what it is, why it was designed the way it was, and what research has reported on the brain.
At a glance
- Class
- Synthetic heptapeptide, ACTH (4-10) analog
- Sequence
- Met-Glu-His-Phe-Pro-Gly-Pro 1
- Molecular formula
- C37H51N9O10S
- Molecular weight
- ≈ 813.9 g/mol
- Origin
- Developed in Russia, where it is used clinically
- Appearance
- White lyophilized powder
- Our fill size
- 10mg
An ACTH fragment without the hormone effects
Adrenocorticotropic hormone (ACTH) is a pituitary hormone best known for driving cortisol release from the adrenal glands. Its short 4–10 fragment keeps some of ACTH's activity in the brain but not its hormonal effect on the adrenals. Semax is that fragment, Met-Glu-His-Phe-Pro, extended with a Pro-Gly-Pro sequence that makes it more resistant to breakdown by enzymes.1
BDNF and learning
Brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, support the survival of neurons and the strengthening of connections between them that underlies learning. In a 2006 rat study, a single intranasal dose of Semax raised BDNF protein in the hippocampus about 1.4-fold, increased activation of its receptor about 1.6-fold, and raised BDNF and TrkB gene activity about 3-fold and 2-fold. Treated animals also learned a conditioned avoidance task better, and the authors proposed that Semax affects cognition through this BDNF/TrkB system.1
Brain-ischaemia research
Semax has been used in Russia in the treatment of stroke, which led researchers to look for how it works at the gene level.2 In a 2014 study of rats with an induced stroke (permanent blockage of a brain artery), Semax mainly changed the activity of genes linked to the immune system: 24 hours after the stroke, immune-response genes made up more than half of the genes whose activity it altered. It also changed genes involved in blood-vessel development, which the authors linked to restoring blood supply to damaged tissue.2
Semax is not approved as a medicine in the United States. The findings above come from animal models.
Where Semax is used in the lab
Laboratory research on Semax focuses on learning and memory in animal models, neuroprotection in models of cerebral ischaemia, neurotrophin signalling and gene expression. It is often studied alongside Selank, a related peptide researched for anxiety-related behaviour, and the two are available together as Semax / Selank.
Handling Semax in the lab
Lyophilized Semax is stable stored frozen at −4 °F and protected from light. Let a vial reach room temperature before opening, reconstitute with bacteriostatic water added slowly down the side of the vial, swirl rather than shake, and keep the solution refrigerated at 36–46 °F.
Before using any lot, check its certificate of analysis. Our current Semax lot, VD-SX10-2610, tested at 99.10% purity by HPLC with identity confirmed by LC-MS at VeriPure Labs. View the certificate ↗ or see every lot on our lab reports page.
Frequently asked questions
What is Semax made from?
Semax is a synthetic seven-amino-acid peptide: the 4–10 fragment of ACTH (Met-Glu-His-Phe-Pro) extended with Pro-Gly-Pro for stability.
Does Semax act like ACTH?
The ACTH (4–10) fragment keeps some of ACTH’s activity in the brain but not its hormonal effect on the adrenal glands.
How is Semax different from Selank?
Both are short synthetic peptides developed in Russia. Semax is based on an ACTH fragment and is studied mainly for cognition and neuroprotection; Selank is based on the immune peptide tuftsin and is studied mainly for anxiety-related behaviour.
Is Semax for human use?
No. Vivid DNA supplies Semax strictly for laboratory research. It is not a drug, food or supplement, and is not for human or veterinary use.
References
- Dolotov OV, Karpenko EA, Inozemtseva LS, et al. Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus. Brain Research. 2006;1117(1):54–60. PubMed 16996037 ↗
- Medvedeva EV, Dmitrieva VG, Povarova OV, et al. The peptide Semax affects the expression of genes related to the immune and vascular systems in rat brain focal ischemia: genome-wide transcriptional analysis. BMC Genomics. 2014;15:228. doi:10.1186/1471-2164-15-228 ↗
More research overviews
Research use only. Vivid DNA products are sold strictly for laboratory research. They are not drugs, foods, cosmetics or supplements, are not for human or veterinary use, and are not intended to diagnose, treat, cure or prevent any disease. Clinical results described here refer to investigational or approved medicines studied under medical supervision, not to research-grade material. This article summarises published research and has not been evaluated by the Food and Drug Administration.