SELANK TP-7
Selank (also designated TP-7) is a synthetic heptapeptide with the amino-acid sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro (TKPRPGP). It is a synthetic analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide (Thr-Lys-Pro-Arg) derived from the heavy chain of human immunoglobulin G; Selank extends that core sequence with a C-terminal Pro-Gly-Pro tripeptide to confer resistance to enzymatic degradation and a longer duration of action. The compound is catalogued under CAS number 129954-34-3, with a molecular formula of C₃₃H₅₇N₁₁O₉ and a molecular weight of approximately 751.9 g/mol (PubChem CID 11765600). It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences.
Selank has been studied in cell-culture, animal, and human research, predominantly within the Russian research program from which it originates, where it is an approved prescription anxiolytic. It is supplied here strictly as a research-use chemical for in vitro and laboratory investigation. It is not approved by the FDA, EMA, or any other Western regulatory authority for any indication.
Important note on the evidence base: A substantial portion of the published Selank literature originates from a single national research program (the Institute of Molecular Genetics and affiliated Russian groups), and much of it is published in Russian-language journals. While this body of work includes clinical studies, large independent Western randomized controlled trials are not available. Researchers should weight the single-source character of much of the evidence accordingly and consult the primary literature in the References section.
Available Products
Mechanism of Action
The research literature on Selank centers on its modulation of neurotransmitter and neurotrophic systems and its relationship to the immunomodulatory peptide tuftsin. The pathways below are drawn predominantly from the originating program’s preclinical and clinical work and are presented as mechanistic characterization, not therapeutic claims.
Tuftsin lineage and metabolic stabilization
Selank’s design rationale is the stabilization of tuftsin’s biological activity. Native tuftsin is rapidly degraded, limiting its research utility; appending the Pro-Gly-Pro tripeptide to the C-terminus markedly slows proteolysis, producing a peptide that reaches the central nervous system within minutes of administration in research models. This tuftsin lineage connects Selank to both neuropeptide and immunomodulatory research domains [1]. Tuftsin itself is a fragment of the heavy chain of immunoglobulin G with documented effects on phagocytic and immune-cell activity, so Selank is studied not only as a centrally acting peptide but also in the context of immune and inflammatory signalling, a dual character that distinguishes it from purely neuroactive analogues.
GABAergic and serotonergic modulation
The most-studied central mechanism attributed to Selank is modulation of inhibitory and monoaminergic neurotransmission. The literature describes effects on the GABAergic system — the principal inhibitory neurotransmitter system — and on serotonergic signalling, which together are proposed to underlie the anxiolytic-type effects reported in animal models and Russian clinical studies, notably without the sedative profile associated with benzodiazepines [2].
Enkephalin and gene-expression effects
Selank has been reported to influence the enkephalin system, including effects on the stability of leu-enkephalin in serum, and transcriptomic studies in rat hippocampus reported changes in the expression of genes related to neurotransmission, neurotrophic signalling (including BDNF), and immune-cytokine pathways following administration [3]. A single dose was reported to alter the mRNA levels of dozens of genes, many encoding plasma-membrane and transmembrane proteins, and in vitro work in neuronal cell lines has linked Selank’s activity to genes involved in GABAergic neurotransmission, supporting a proposed role as a positive allosteric modulator of that system [4]. These gene-expression findings are the basis for the proposed combined anxiolytic, nootropic, and immunomodulatory profile described in the literature.
None of the mechanisms summarized here have been verified in large independent Western clinical trials.
Forms and Use in the Research Literature
The information below reflects how Selank appears in the published literature. It is reported strictly for research-reference purposes and does not constitute administration recommendations of any kind.
Behavioral and pharmacology models. Animal work has used Selank at microgram-per-kilogram amounts to examine anxiety-type behavior, learning and memory endpoints, and effects in models such as naloxone-precipitated morphine withdrawal, where it was compared against benzodiazepine reference compounds [1].
Transcriptomic and immunomodulatory research. Studies have used cDNA microarray approaches to characterize Selank’s effects on the hippocampal transcription profile and have examined its influence on cytokine expression under stress conditions, reflecting its dual neuropeptide and immunomodulatory research interest [3].
Clinical research record. In its country of origin, Selank has been evaluated in clinical studies of generalized anxiety and asthenic disorders, where its anxiolytic profile was reported as comparable to benzodiazepine comparators with additional antiasthenic effects. As noted above, this record is largely single-source and not replicated in independent Western trials [2].
Capsule format. This product is supplied by Captide Labs in capsule form, consistent with the brand’s capsule-first catalog. Researchers should note that the published Selank literature predominantly used intranasal and parenteral administration, so oral or encapsulated delivery represents a distinct research variable, and oral bioavailability of this peptide is not well characterized.
Stability and storage. Selank is supplied as a lyophilized powder, typically stored frozen, protected from light, with reconstituted solutions kept cold and used promptly. The Pro-Gly-Pro extension confers greater stability than native tuftsin, but standard peptide-handling precautions apply. Each lot supplied by Captide Labs is accompanied by a batch-specific Certificate of Analysis documenting identity and purity by HPLC.
Adverse-event profile. The Russian clinical literature reported a favourable tolerability profile, notably the absence of the sedation and dependence associated with benzodiazepines, but adequately powered independent safety data is not available, and safety for any use outside that research context has not been established to a Western regulatory standard.
References
- Kozlovskii II, Danchev ND. The optimizing action of the synthetic peptide Selank on a conditioned active avoidance reflex in rats. Neurosci Behav Physiol. 2003;33(7):639–643. doi:10.1023/A:1024452815753 · PubMed: 14552533
- 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: 18454096
- Kolomin TA, Agapova TY, Agniullin YV, et al. Changes in the Transcription Profile of the Hippocampus in Response to Administration of the Tuftsin Analog Selank. Neurosci Behav Physiol. 2014;44(8):849–855. doi:10.1007/s11055-014-9992-4
- Filatova E, Kasian A, Kolomin T, et al. GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells. Front Pharmacol. 2017;8:89. doi:10.3389/fphar.2017.00089 · PubMed: 28280466