Selank and Cognitive Enhancement: What Has Been Studied

What the research covers

Selank has been tested in small Russian trials in people with anxiety, not in healthy adults for memory. Its effects on BDNF, a brain growth factor, have been studied only in rodent (rat) groups.

Selank is a man-made peptide based on tuftsin, a peptide the body makes. One trial gave 62 patients with anxiety or nervous exhaustion either selank or medazepam. Both drugs eased anxiety to a similar degree. Selank also had anti-fatigue and stimulant effects. A second study of 60 patients with anxiety compared it with phenazepam. The authors reported clear anti-anxiety effects and mild effects on thinking.

A third trial gave 70 patients phenazepam, with or without selank. Adding selank cut the side effects of phenazepam. These included poor attention and memory. The abstracts of these Russian papers do not give the selank dose. One brain scan study of 52 healthy people looked at links between brain areas after selank, semax or placebo. It did not report a memory or thinking test.

In a rodent (rat) study, 0.3 mg per kg a day by injection for 7 days improved object recognition. This was in 9-month-old animals not given alcohol. In another rodent (rat) study, selank given in the nose changed BDNF in the hippocampus. A third rodent (rat) study found changes in genes linked to GABA signalling.

Sources

1. Zozulia AA, Neznamov GG, Siuniakov TS, et al. Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia Zh Nevrol Psikhiatr Im S S Korsakova (2008). PMID 18454096 Russian trial, 62 patients with generalised anxiety disorder or neurasthenia; selank (30) compared with medazepam (32).
2. Medvedev VE, Tereshchenko ON, Israelian AIu, et al. A comparison of the anxiolytic effect and tolerability of selank and phenazepam in the treatment of anxiety disorders Zh Nevrol Psikhiatr Im S S Korsakova (2014). PMID 25176261 Russian study, 60 patients with anxiety and somatoform disorders; selank compared with phenazepam.
3. Medvedev VE, Tereshchenko ON, Kost NV, et al. Optimization of the treatment of anxiety disorders with selank Zh Nevrol Psikhiatr Im S S Korsakova (2015). PMID 26356395 doi:10.17116/jnevro20151156133-40 Russian trial, 70 patients: phenazepam alone (30) or with selank (40); fewer phenazepam side effects with the combination.
4. Panikratova YR, Lebedeva IS, Sokolov OY, et al. Functional Connectomic Approach to Studying Selank and Semax Effects Dokl Biol Sci (2020). PMID 32342318 doi:10.1134/S001249662001007X Brain scan (fMRI) study in 52 healthy people after selank, semax or placebo; connectivity only, no memory test.
5. Kolik LG, Nadorova AV, Antipova TA, et al. Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats Bull Exp Biol Med (2019). PMID 31625062 doi:10.1007/s10517-019-04588-9 Rodent (rat) study: 0.3 mg/kg a day by injection for 7 days; better object recognition and brain BDNF changes.
6. Inozemtseva LS, Karpenko EA, Dolotov OV, et al. Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus in vivo Dokl Biol Sci (2008). PMID 18841804 doi:10.1134/s0012496608040066 Rodent (rat) study: selank given in the nose changed BDNF expression in the hippocampus.
7. Volkova A, Shadrina M, Kolomin T, et al. Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission Front Pharmacol (2016). PMID 26924987 doi:10.3389/fphar.2016.00031 Rodent (rat) study: selank changed the activity of genes involved in GABA signalling.