Selank

Overview

Selank is a synthetic heptapeptide: a chain of seven amino acids. It is derived from tuftsin, an endogenous four-amino-acid peptide that plays a role in immune defense. To that tuftsin fragment a short stabilising tail (Pro-Gly-Pro) was added. That tail protects the molecule from rapid breakdown by enzymes, so it remains active in the body longer than natural tuftsin. Selank was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences.

What is unusual about Selank is the combination of properties it shows. In preclinical models (work in cells and laboratory animals) it shows both immune-regulating effects and anxiolytic-like, cognition-supporting effects. That dual orientation toward both the immune system and the central nervous system is uncommon: most regulatory peptides act on one or the other. That intersection is what makes Selank scientifically interesting.

Most of the research comes from Russian institutes. In Russia, Selank holds regulatory registration for certain uses. The body of Western, independently replicated clinical data is, however, limited. This profile weighs the existing findings against that context: the evidence is consistent, but concentrated in a single research tradition.

As with all compounds in the Peptalis database, this profile summarises the state of the research; it constitutes no efficacy claims or product recommendations.

Mechanism of action

Selank does two things at once, and that is unusual. In the brain it makes the calming GABA system (the system that settles nerve cells) more sensitive, without taking over that brake itself. At the same time it nudges the immune response, an echo of tuftsin: the immune peptide it is derived from.

GABAergic and neurotrophic signalling

• Acts as a positive allosteric modulator of the GABA receptor: strengthening receptor function without occupying the usual binding site
• In hippocampal slices, increases spontaneous inhibitory synaptic activity, a mechanism linked to its anxiolytic-like effects in animal models
• Influences the expression of brain-derived neurotrophic factor (BDNF), a protein that supports the growth and maintenance of nerve cells

Immune modulation

• Reflects the lineage of tuftsin as an immune-regulating peptide
• Modulates the balance between two groups of immune signalling molecules, what immunologists call Th1- and Th2-type cytokines: roughly the cell-based and antibody-based arms of defense
• Regulates the expression of interleukin-6 (IL-6), an inflammation-signalling molecule, in blood cells; in animal models also alters the activity of specific immune-related genes

Interaction with the opioid system

• Interacts with enzymes that break down enkephalins. Enkephalins are endogenous molecules, related to opioids, that regulate pain and mood
• Preclinical work indicates that this opioid system plays a role in how strongly the anxiolytic-like effect manifests in individual animals

Research findings

• Anxiolytic-like effects across multiple rodent behavioural models
• Improved performance in learning and memory tasks in animal models
• Reduced aversive signs in withdrawal models (alcohol, morphine) in rats, comparable in magnitude to diazepam
• Modulation of BDNF expression in the hippocampus and prefrontal cortex
• Increased spontaneous inhibitory synaptic activity in hippocampal CA1 neurons
• In a small human study in patients with anxiety-asthenic complaints, changes in the Th1/Th2 cytokine balance and IL-6 were measured after 14 days of administration
• In a placebo-controlled human resting-state fMRI study in 52 healthy participants, changes in the functional connectivity around the amygdala were measured after Selank administration

Behavioural findings (preclinical)

• Anxiolytic-like effects across multiple rodent behavioural models
• Improved performance in learning and memory tasks in animal models
• Reduced aversive signs in withdrawal models (alcohol, morphine) in rats, comparable in magnitude to diazepam, a widely used sedative

Neurotrophic and synaptic mechanisms

• Modulation of BDNF expression in the hippocampus and prefrontal cortex, two brain regions important for memory and self-regulation
• Increased spontaneous inhibitory synaptic activity in hippocampal CA1 neurons, a specific cell type in the hippocampus

Immune and human findings

• Small human study in patients with anxiety-asthenic complaints: shifts in Th1/Th2 cytokine balance and IL-6 measured after 14 days of Selank administration
• Placebo-controlled resting-state fMRI study in 52 healthy participants: structured outcome on functional connectivity around the amygdala (the brain region central to anxiety) following Selank administration. Both are small and originate from the same research tradition.

Research context

Selank has mainly been studied in Russian, and to a lesser extent European, research institutions. The preclinical evidence is consistent across multiple models and points to a dual profile: immune modulation and neuroactive effects. That intersection is what distinguishes the compound scientifically. Most regulatory peptides act on one of the two systems, not both.

Human research exists, but is limited. There are a few small human studies, including an immunological cytokine study and an fMRI connectivity study, both originating largely from the same research tradition. Independent Western replication with standardised methods is largely absent.

The Russian regulatory registration is sometimes cited as evidence of effect. The underlying registration data, however, are not accessible and replicated in the same way as in Western pathways. For research groups, a clear gap lies here: independent, controlled studies could confirm or qualify the dual profile.

Open questions

• Independent Western clinical data with standardised endpoints are limited; the human studies are small and largely from a single research tradition. Controlled trials outside that tradition could test the findings.
• The full receptor-binding profile has not yet been mapped. Pharmacological binding studies could fill this in.
• Dose-response relationships differ between experimental paradigms and have not been systematically established. Standardised dose ranges would clarify this.
• Long-term effects on cognition call for longitudinal studies.
• The relationship between the immunomodulatory and the neuroactive mechanism is not yet resolved. Research that measures both axes simultaneously could untangle this intersection.

Research outlook

Independent, controlled human studies with standardised endpoints, beyond the original research tradition

Characterisation of the receptor-binding profile and the mechanism of action

Further dissection of the intersection between immune modulation and neuroprotection

Research into its role in stress-related paradigms and possible epigenetic effects: changes in gene activity without changes to the DNA code itself

Exploration of interactions with other neuroactive peptides in controlled models

Scientific interest

Dual immune-regulating and neuroactive profile, rare among regulatory peptides.

Modulation of BDNF expression and the GABAergic system.

Intersection of immune regulation and research into cognitive function.

Derived from tuftsin, with improved stability, a model example of peptide optimisation.

Specifications

References

1. Immunomodulatory effects of selank in patients with anxiety-asthenic disorders · Uchakina ON, Uchakin PN, Miasoedov NF et al. · Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova · 2008
2. The temporary dynamics of inflammation-related genes expression under tuftsin analog Selank action · Kolomin T, Shadrina M, Slominsky P, Limborska S, Myasoedov N · Mol Immunol · 2013
3. Efficacy of peptide anxiolytic selank during modeling of withdrawal syndrome in rats with stable alcoholic motivation · Kolik LG, et al. · Bulletin of Experimental Biology and Medicine · 2014
4. Effect of Selank on Spontaneous Synaptic Activity of Rat Hippocampal CA1 Neurons · Povarov IS, et al. · Bulletin of Experimental Biology and Medicine · 2017
5. Tuftsin - Properties and Analogs · Siebert A, et al. · Current Medicinal Chemistry · 2017
6. Peptide-based Anxiolytics: The Molecular Aspects of Heptapeptide Selank Biological Activity · Vyunova TV, Andreeva L, Shevchenko K, Myasoedov N · Protein Pept Lett · 2018
7. Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats · Kolik LG, Nadorova AV, Antipova TA et al. · Bulletin of Experimental Biology and Medicine · 2019
8. Functional Connectomic Approach to Studying Selank and Semax Effects · Panikratova YR, et al. · Doklady Biological Sciences · 2020
9. Heptapeptide Selank Attenuates Aversive Signs of Morphine Withdrawal in Rats · Konstantinopolsky MA, et al. · Bulletin of Experimental Biology and Medicine · 2022

Availability

In stock · Batch PEP-SEL-2026-01 · HPLC 98.44 % · released 21 Jun 2026

• Selank 10 mg · product page with price and batch CoA