Selank Research: What the Studies Show
Selank (TP-7) is a synthetic heptapeptide derived from the immunomodulator tuftsin, developed at the Institute of Molecular Genetics of the Russian Academy of Sciences. It is studied for anxiolytic, nootropic and immunomodulatory activity. Selank is registered for clinical use in Russia; it is not approved by the U.S. FDA. The published literature therefore comes mainly from Russian and Eastern European research institutions.
Mechanism of action
Selank is a tuftsin analogue — the parent peptide is an immune-signalling fragment — extended with a Pro-Gly-Pro tail that resists enzymatic breakdown and gives it central nervous system activity.
Molecular work points to positive allosteric modulation of GABAergic signalling rather than direct receptor agonism, which is the leading explanation for anxiolytic effects without sedation or dependence.
A second mechanism is inhibition of enkephalin-degrading enzymes, extending the half-life of the body's own opioid-like stress-buffering peptides.
Its tuftsin origin also gives it measurable effects on pro-inflammatory cytokine output under stress conditions.
The studies
The generalised anxiety comparison below is human clinical research conducted in Russia; the remaining entries are animal and biochemical studies.
Human clinical efficacy
Selank versus medazepam in generalized anxiety disorder and neurasthenia
Whether a peptide anxiolytic can match a benzodiazepine without the sedative and cognitive cost.
Comparative human trial in 62 patients with generalized anxiety disorder and neurasthenia · Selank compared against the benzodiazepine medazepam · anxiolytic, sedative and cognitive endpoints
- 62
- Patients
- Comparable
- Anxiolytic effect vs medazepam
- Not observed
- Sedation / cognitive impairment
- Present
- Anti-asthenic & psychostimulant activity
- Selank's anxiolytic effect was statistically comparable to the benzodiazepine medazepam in this cohort.
- Unlike the benzodiazepine comparator, it produced no sedative or cognitive-impairing effects.
- It additionally showed anti-asthenic (anti-fatigue) and mild psychostimulant activity — the opposite of the benzodiazepine side-effect direction.
- Sample size is modest at 62 patients and the work has not been replicated in large Western trials.
GABAergic mechanism
Selank and the expression of genes involved in GABAergic neurotransmission
Which neurotransmitter gene programmes Selank switches on, and how fast.
Expression analysis of 84 neurotransmitter-related genes in rat frontal cortex · sampling at 1 and 3 hours post-administration
- 84
- Genes profiled
- 1-3 hours
- Time to expression change
- Substantially altered
- GABAergic signalling genes
- Selank drastically altered expression of genes governing GABAergic signalling — the brain's primary inhibitory, calming pathway — within one to three hours.
- The pattern is consistent with Selank acting as a positive allosteric modulator of GABA receptors rather than a direct agonist.
- That distinction is the proposed reason it does not produce the dependence associated with benzodiazepines.
Selank enhances the effect of diazepam under unpredictable chronic mild stress
Whether combining Selank with a benzodiazepine outperforms either alone under chronic stress.
Unpredictable chronic mild stress (UCMS) model in rats · Selank alone, diazepam alone and combination arms · anxiety-related behavioural endpoints
- Selank + diazepam
- Most effective arm
- Suppressed
- Stress-induced behaviour
- Reduced
- Implied benzodiazepine dose
- The Selank plus diazepam combination gave the strongest suppression of stress-induced behaviour.
- The authors concluded co-administration could allow a lower benzodiazepine dose, reducing side-effect burden and addiction liability.
- This is a rodent chronic-stress model, not a clinical dosing recommendation.
Endogenous opioid pathway
Inhibition of enkephalin-degrading enzymes as a mechanism of anxiolytic activity
Why anxious subjects burn through their own calming peptides — and whether Selank slows that down.
Biochemical assay of enkephalin degradation in blood · dose-response testing of Selank against enkephalin-degrading enzymes
- Accelerated at baseline
- Enkephalin degradation in severe anxiety
- Dose-dependent
- Enzyme inhibition by Selank
- Extended
- Enkephalin half-life
- Patients with severe generalized anxiety showed rapid degradation of enkephalins — the body's own mood- and pain-regulating opioid peptides.
- Selank dose-dependently inhibited the enzymes responsible, extending enkephalin half-life.
- This gives a second, non-GABA route by which Selank may support stress resilience.
Cognition & learning
Optimizing action of Selank on the Schaffer collateral-CA1 pathway and associative learning
Whether Selank improves memory consolidation, and in which subjects the effect is largest.
Monosynaptic Schaffer collateral-CA1 pyramidal cell pathway recordings · associative learning tasks scoring correct choices and errors
- Increased
- Correct choices
- Reduced
- Errors
- Poor-learner subgroup
- Largest effect
- Selank progressively optimised associative learning and memory consolidation across training sessions.
- The effect was strongest in subjects with initially poor learning ability — correct choices rose and errors fell.
- Upregulation of BDNF in the hippocampus is the proposed underlying mechanism, linking it to the same neurotrophic axis as Semax.
Immunomodulation
Influence of Selank on cytokine levels under conditions of social stress
Whether a tuftsin-derived peptide can damp the inflammatory response to behavioural stress.
Social stress model · measurement of pro-inflammatory cytokines interleukin-1β, interleukin-6 and TNF-α
- Suppressed
- Interleukin-1β
- Suppressed
- Interleukin-6
- Suppressed
- TNF-α
- Selank significantly suppressed the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α raised by behavioural stress.
- Consistent with its origin as a derivative of the immune peptide tuftsin.
- Suggests Selank stabilises central nervous system and immune responses together rather than acting on mood alone.
Receptor pharmacology
Radioligand-receptor binding and GABA-A modulation
How Selank calms the central nervous system without the heavy sedation of conventional tranquillisers.
Radioligand-receptor binding assay on isolated brain cell membranes · testing whether Selank behaves as a positive allosteric modulator of GABA-A receptors
- Altered
- GABA receptor binding efficiency
- Not observed
- Benzodiazepine sub-site binding
- Positive allosteric modulation
- Proposed action
- Selank changed the binding efficiency of GABA receptors, the brain's principal inhibitory system, letting endogenous GABA act more effectively.
- It did not bind the benzodiazepine sub-site — the leading explanation for anxiolytic activity without marked muscle relaxation or cognitive dulling.
- Receptor-level data of this kind is mechanistic; it does not by itself establish clinical benefit.
Neuroprotection
BDNF regulation and protection against ethanol-induced memory impairment
Whether Selank stabilises brain-derived neurotrophic factor during an ethanol-induced memory challenge.
Rat model of ethanol-induced memory impairment · BDNF content measured in the hippocampus and prefrontal cortex · memory-disturbance endpoints
- Stabilised
- Hippocampal BDNF
- Regulated
- Prefrontal cortex BDNF
- Reduced
- Ethanol-induced memory impairment
- Selank regulated BDNF — the principal growth factor for neuronal survival and plasticity — in the two regions most associated with memory and attention.
- Memory impairment provoked by the ethanol challenge was attenuated relative to controls.
- Animal data only; no equivalent human neuroprotection trial has been published.
Human clinical efficacy
Selank versus phenazepam, and optimisation of anxiety treatment
How Selank compares with a benzodiazepine on both effect and tolerability in anxiety disorders.
Clinical comparison of Selank against phenazepam in patients with anxiety disorders, plus a follow-up treatment-optimisation study · anxiolytic efficacy, tolerability and side-effect endpoints
- Comparable
- Anxiolytic effect
- Favoured Selank
- Tolerability
- Fewer
- Sedative side effects
- Selank's anxiolytic effect was comparable to phenazepam in this patient population.
- Tolerability favoured Selank — fewer reports of drowsiness and attention or memory complaints than the benzodiazepine arm.
- The follow-up optimisation paper is why Selank is discussed in the Russian literature as a way to reduce reliance on benzodiazepines rather than as a stand-alone replacement.
Storage & handling
Selank is supplied as a lyophilised powder. Keep sealed vials refrigerated or frozen, protected from light and moisture.
Reconstitute with bacteriostatic water directed slowly down the inner wall of the vial and swirl gently until clear. Do not shake.
Store reconstituted solution at 2-8 °C and use within the stability window set by your lab's standard operating procedures.
All information on this page is provided for laboratory and educational reference only. Peptides Lab SA (PTY) Ltd supplies compounds strictly for in-vitro research use. Nothing here is medical advice, a dosing recommendation, or a claim of human safety or efficacy.