What Is Selank?
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a modified analog of tuftsin, an endogenous tetrapeptide fragment of the immunoglobulin G heavy chain. The addition of three proline-glycine-proline residues to the tuftsin core sequence was designed to improve metabolic stability and enable central nervous system activity.
Although tuftsin itself is studied primarily for its immunomodulatory activity, Selank's modifications shifted the peptide's profile toward the central nervous system. In Russia, Selank has been investigated in clinical research for decades as a potential anxiolytic and cognitive-modulating agent, and it remains approved for certain indications in the Russian Federation while remaining a research compound elsewhere.
Peptide Profile
Full Name: Selank (Tuftsin analog)
Sequence: Thr-Lys-Pro-Arg-Pro-Gly-Pro
Molecular Weight: 751.88 g/mol
CAS Number: 129954-34-3
Classification: Synthetic heptapeptide, anxiolytic
Mechanism of Action
The mechanism by which Selank produces its observed anxiolytic and cognitive effects is multi-faceted and remains under active investigation. Research has identified several pathways through which Selank appears to exert its biological activity.
GABAergic Modulation
Preclinical research has observed that Selank influences the GABAergic system, a central inhibitory neurotransmitter pathway associated with anxiolytic activity. Unlike benzodiazepines, which act directly at the GABA-A receptor, Selank appears to exert its effects indirectly, potentially through modulation of GABA receptor expression and signaling rather than direct receptor binding.
Enkephalinase Inhibition
Studies have suggested that Selank can inhibit the activity of enkephalinase, an enzyme responsible for degrading endogenous enkephalins. By extending the half-life of endogenous opioid peptides, this activity may contribute to Selank's observed analgesic and anxiolytic effects in preclinical models.
Serotonergic and Dopaminergic Influence
Research has examined Selank's influence on monoamine neurotransmitter systems, with studies reporting modulatory effects on serotonin and dopamine turnover in select brain regions. These findings have contributed to investigation of Selank as a potential cognitive and mood-modulating compound in preclinical research.
BDNF and Neuroplasticity
Research has observed that Selank administration may influence the expression of brain-derived neurotrophic factor (BDNF) and other neuroplasticity-related signaling molecules. These effects have been linked to observations of cognitive enhancement in preclinical rodent learning and memory models.
Immunomodulation
As a tuftsin analog, Selank retains some of the parent peptide's immunomodulatory profile. Research has reported effects on cytokine expression, T-cell activity, and inflammatory signaling, though these applications are secondary to the peptide's central nervous system research focus.
Research Overview
Selank has been investigated for several decades, with a substantial body of preclinical and clinical research conducted primarily in Russia. Research has focused on anxiolytic, cognitive, and mood-related applications.
| Research Area | Key Findings | Study Type |
|---|---|---|
| Anxiolytic Activity | Russian clinical studies have investigated Selank in generalized anxiety disorder and reported reductions in anxiety rating scores | Human clinical |
| Cognitive Function | Preclinical research has reported improvements in learning, memory, and attention in rodent models, with some supportive clinical data | In vivo (rodent) / clinical |
| Mood and Depression | Studies have examined Selank's effects on depressive-like behavior in rodent models, with investigations of co-administration alongside standard antidepressants | In vivo (rodent) |
| Stress and Adaptation | Research has examined Selank's influence on stress response markers and adaptive behavior in animal stress models | In vivo (rodent) |
| Immune Modulation | Consistent with its tuftsin lineage, Selank has been investigated for effects on immune parameters including cytokine balance | In vivo / in vitro |
| Neuroprotection | Preclinical models of ischemic and excitotoxic neuronal injury have examined Selank's potential protective activity | In vivo (rodent) |
Most of Selank's published research has been conducted in Russia, where the peptide has approved clinical applications. Research availability in English-language literature is more limited than for many comparably studied peptides, which has contributed to relatively lower international awareness despite the compound's long research history.
Common Areas of Research Interest
The scientific focus on Selank centers on its central nervous system activity and its unique profile as a non-sedating, non-addictive anxiolytic candidate in preclinical models.
- Generalized anxiety research, Selank is one of the more clinically developed peptide anxiolytics in research literature, particularly in Russian clinical studies
- Cognitive enhancement, Preclinical models have consistently reported improvements in learning, memory, and attention following Selank administration
- Stress response research, Studies have investigated Selank's ability to attenuate behavioral and physiological markers of acute and chronic stress
- Depression research, Preclinical models have examined Selank alone and in combination with standard antidepressant protocols
- Immune system integration, Research has explored the peptide's dual central and immune modulating profile
- Non-addictive anxiolysis, A key area of interest is Selank's apparent lack of tolerance, dependence, or withdrawal in available preclinical data
Pharmacokinetics
Selank's pharmacokinetic profile is notable for its ability to cross the blood-brain barrier despite its peptide nature, a property attributed to its structural modifications.
Selank has a short plasma half-life measured in minutes, but its central nervous system effects have been reported to persist for substantially longer periods in preclinical and clinical studies. This disconnect between peripheral pharmacokinetics and central pharmacodynamics is a common observation across small-peptide anxiolytics and is a reason intranasal administration has been explored as a research route.
Comparison to Similar Peptides
Selank is often considered alongside other small peptides investigated for cognitive, anxiolytic, or neuroprotective effects.
| Feature | Selank | Semax | Tuftsin |
|---|---|---|---|
| Origin | Synthetic tuftsin analog | Synthetic ACTH(4-7) analog | Endogenous IgG-derived tetrapeptide |
| Primary Research Focus | Anxiolytic, cognitive | Cognitive, neuroprotective | Immunomodulatory |
| Amino Acids | 7 | 7 | 4 |
| BBB Penetration | Yes | Yes | Limited |
Frequently Asked Questions
Sources & References
- Zozulya AA, Kost NV, Yu Sokolov O, et al. "The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity." Bull Exp Biol Med. 2001;131(4):315-7. PubMed
- Kozlovskaya MM, Kozlovskii II, Val'dman EA, Seredenin SB. "Selank and short peptides of the tuftsin family in the regulation of adaptive behavior in stress." Neurosci Behav Physiol. 2003;33(9):853-60. PubMed
- 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;108(4):38-48. PubMed
- 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;167(5):641-644. PubMed
- Semenova TP, Kozlovskaya MM, Zakharova NM, et al. "Effect of selank on cognitive processes after damage inflicted to the cerebral catecholamine system during early ontogeny." Bull Exp Biol Med. 2007;144(5):689-91. PubMed
- Kolik LG, Nadorova AV, Kozlovskaya MM. "Efficacy of peptide anxiolytic selank during modeling of withdrawal syndrome in rats with stable alcoholic motivation." Bull Exp Biol Med. 2014;157(1):52-5. PubMed
- Kozlovskiĭ II, Andreeva LA, Kozlovskaia MM, et al. "[The role of opioid system in peculiarities of anti-anxiety effect of peptide anxiolytic selank]." Eksp Klin Farmakol. 2012;75(2):10-3. PubMed
- Doyno CR, White CM. "Sedative-Hypnotic Agents That Impact Gamma-Aminobutyric Acid Receptors: Focus on Flunitrazepam, Gamma-Hydroxybutyric Acid, Phenibut, and Selank." J Clin Pharmacol. 2021;61 Suppl 2:S114-S128. PubMed
Explore Selank
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View Selank Products — $65This product is intended for research and laboratory use only. It is not intended for human consumption.