Neuropeptides: Semax, Selank and family
Semax and Selank come from the same tradition: take a natural molecule, cut off the part you do not need and add a tail to make it stable.
The Russian school
This group of peptides was developed in Russia in the 1980s and 1990s, following a fixed approach. You start from a substance the body makes itself, find the shortest fragment that still carries the wanted effect, and so strip away the rest of the action. Then you add a short tail to protect it against enzymes.
That explains why all these names end in the same three letters and why they are all short chains.
Semax: ACTH without the hormone
Semax derives from ACTH, the hormone that prompts the adrenal gland to make cortisol. The fragment that remains no longer carries that hormonal action. What is left is the part the literature links to learning, attention and protection of nerve cells.
The mechanism named most often is BDNF, a protein nerve cells use to maintain connections and build new ones.
Selank: tuftsin with a tail
Selank is built on tuftsin, a small peptide from the immune system. In the literature the emphasis here is on tension and mood rather than attention. The two are therefore often placed side by side: one leaning towards calm, the other towards focus.
Both exist in an N-acetyl variant. That means an acetyl group has been placed at the start of the chain, a small cap shielding the end from enzymes that attach there. The substance stays intact longer as a result. Otherwise it is the same molecule.
The short Russian series
Besides Semax and Selank there is a series of even shorter peptides, three or four amino acids long, each aimed at a different tissue. Epithalon comes from the pineal gland and appears in research on ageing and telomeres. Pinealon is linked to nerve tissue, Cortagen to peripheral nerves, Crystagen to immune tissue.
Because these chains are so short, they keep well as powders and are easy to handle. That makes them popular as research models, quite apart from what else is known about them.
What to keep in mind with this group
A large part of the literature on these substances was published in Russian and not always translated. That is not a disqualification, but it does mean a search in English language databases turns up less than exists, and that independent replication of results is often missing.
This site is made by the team behind Apex Bio Research, a Dutch supplier of research peptides with a certificate of analysis per batch.
Visit the shopThis site explains what the scientific literature says about peptides. It is not medical advice and not a set of instructions. The substances discussed here are research compounds: they are not approved for use in humans or animals. If you have a health question, see a doctor.
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