Peptide comparison
Both were developed in Russia, both carry the same stabilising Pro-Gly-Pro “tail” and both are studied mainly by the intranasal route. But they start from different molecules and target different processes: Semax neuroprotection and cognition; Selank anxiety and immune modulation.
Compare mechanism, class, receptors and evidence. All compounds are offered with ≥99% purity verified by HPLC and a batch COA.
| Semax | Selank | |
|---|---|---|
| Parent molecule | ACTH fragment 4-10 | Tuftsin (immunomodulatory tetrapeptide) |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Length | 7 amino acids | 7 amino acids |
| Research focus | Neuroprotection, cognition, cerebral ischaemia | Anxiety, stress, immune modulation |
| Described mechanisms | Increased BDNF and neurotrophic signalling | GABAergic and monoamine modulation |
| Most studied route | Intranasal | Intranasal |
| Status | Registered as a medicine in Russia; not approved in the US or EU | Registered as a medicine in Russia; not approved in the US or EU |
The fundamental difference lies in the molecule they start from. Semax derives from an ACTH fragment that keeps effects on the nervous system without the hormonal action on the adrenal gland; the literature links it to increased neurotrophic factors such as BDNF, and it has been studied mainly in models of ischaemia and cognitive function. Selank derives from tuftsin, an immunoglobulin fragment with immunomodulatory activity, and has been studied for anxiolytic effects related to the GABAergic system.
What they share is the design strategy: adding Pro-Gly-Pro to the C-terminus to slow their breakdown. Most of the evidence comes from Russian groups, with preclinical and clinical studies largely published in journals from that country; that concentration of sources should be taken into account when weighing it.
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Their origin and research focus: Semax derives from ACTH and is studied for neuroprotection and cognition; Selank derives from tuftsin and is studied for anxiolytic and immunomodulatory effects.
It is a stabilising extension: the Pro-Gly-Pro tripeptide at the C-terminus makes both molecules more resistant to the enzymes that break them down.
Both are registered as medicines in Russia, but they are not approved in the United States or the European Union. The material in this catalogue is for research use only.
Purity ≥99% verificada por HPLC and batch COA.
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