N-Acetyl-Selank [Peptide]

Description

What is N-Acetyl Selank?

N-Acetyl Selank is a synthetic N-terminally acetylated derivative of Selank, a heptapeptide originally developed by the Institute of Molecular Genetics of the Russian Academy of Sciences in collaboration with the V.V. Zakusov Institute of Pharmacology. The parent compound, Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro; TKPRPGP), is a synthetic analogue of tuftsin — a naturally occurring immunomodulatory tetrapeptide (Thr-Lys-Pro-Arg) derived from the Fc region of the human immunoglobulin G heavy chain — extended at the C-terminus with Pro-Gly-Pro to enhance metabolic stability and prolong biological activity. N-Acetyl Selank carries an acetyl group at the N-terminus of this heptapeptide sequence, a structural modification intended to further increase resistance to aminopeptidase-mediated degradation in biological matrices and thereby extend effective exposure time in experimental systems.

Research on N-Acetyl Selank specifically is limited in published peer-reviewed literature; the majority of available mechanistic and pharmacological data pertains to the parent compound Selank. N-Acetyl Selank is expected to share Selank’s core pharmacological profile — incorporating GABAergic modulation, enkephalinase inhibition, serotonin and monoamine system interactions, BDNF expression modulation, and immunomodulatory activity — with the acetylation potentially contributing to enhanced metabolic stability in in vitro assay systems. Direct comparative data between Selank and N-Acetyl Selank in preclinical models have not been published at the time of this writing.

N-Acetyl Selank is not approved by the Food and Drug Administration for human or veterinary use. It is not a dietary supplement and is not intended for human consumption or therapeutic self-administration. All RCDbio research compounds are supplied strictly for laboratory and research purposes only.

Chemical Properties

Property	Detail
Product Type	Synthetic N-Terminally Acetylated Heptapeptide (Tuftsin Analogue)
Product Name	N-Acetyl Selank
Application	Scientific / Research Use Only
CAS Number	No widely published dedicated CAS for N-Acetyl Selank; parent Selank CAS: 129954-34-3
Molar Mass	~793.93 g/mol (calculated; free base; based on Selank 751.887 g/mol + acetyl group +42.04 g/mol)
Chemical Formula	C35H59N11O10
PubChem CID	133082488 (N-Acetyl Selank)
Parent Compound	Selank (TKPRPGP); PubChem CID 11765600; CAS 129954-34-3; MW 751.887 g/mol; C33H57N11O9
Amino Acid Sequence	Ac-Thr-Lys-Pro-Arg-Pro-Gly-Pro (Ac-TKPRPGP); N-terminal acetylation of Selank sequence
Structural Origin	C-terminally extended analogue of tuftsin (Thr-Lys-Pro-Arg); extended with Pro-Gly-Pro for stability; N-terminus acetylated
Synonyms	N-Ac-Selank; Acetyl-Selank; N-acetyl-TKPRPGP
Physical Form	Lyophilized white to off-white powder
Solubility	Soluble in sterile water and PBS; soluble in dilute acetic acid
Storage (Lyophilized)	−20°C; sealed container; protected from light and moisture
Storage (Reconstituted)	4°C; use within 48–72 hours; avoid repeated freeze-thaw cycles
Purity	≥98% (HPLC verified, independent third-party laboratory analysis; COA available per batch)
WADA Status	Selank and its derivatives are not explicitly named on the 2026 WADA Prohibited List. As a non-approved synthetic peptide with CNS-active properties, S0 (Non-Approved Substances) provisions may apply in sport-adjacent research contexts. Verify current status at GlobalDRO.com before use.

How Does N-Acetyl Selank Work?

N-Acetyl Selank is expected to share the multi-pathway pharmacological profile of parent Selank, with the N-terminal acetylation providing enhanced resistance to aminopeptidase-mediated degradation. The following mechanisms are derived from Selank research literature; direct mechanistic data specific to N-Acetyl Selank in isolated cell or in vivo systems have not been published in peer-reviewed literature at the time of this writing.

Enkephalinase Inhibition Pathway

The most extensively characterised mechanism of Selank is dose-dependent inhibition of enkephalin-degrading enzymes (enkephalinases) in plasma and brain tissue. In clinical studies of patients with generalised anxiety disorder (GAD), reduced enkephalin half-life and decreased total enkephalinase activity were observed in blood preparations, consistent with a pathogenic role for enhanced enkephalin hydrolysis in anxiety states. Selank (IC50: 15 μM) dose-dependently inhibited enzymatic hydrolysis of plasma enkephalin in these preparations, demonstrating greater potency than standard peptidase inhibitors bacitracin and puromycin [Zozulya et al., 2001]. This mechanism preserves endogenous leucine- and methionine-enkephalin concentrations, prolonging their anxiolytic and analgesic activity without direct opioid receptor agonism.

GABAergic Neurotransmission Modulation

In isolated cell and rodent preclinical models, Selank has been investigated for modulation of GABAergic neurotransmission pathways. Transcriptomic studies in rat hippocampal preparations following single and chronic Selank administration identified changes in the expression of genes associated with GABA-A receptor subunit composition and GABAergic inhibitory signalling. Unlike benzodiazepines — which act as GABA-A receptor positive allosteric modulators and produce sedation, cognitive impairment, and dependence — Selank’s GABAergic effects in preclinical models were not associated with these adverse effects, suggesting a distinct mechanism of GABAergic modulation [Semenova et al., 2010].

BDNF Expression and Hippocampal Neuroplasticity

In rodent preclinical models, intranasal administration of Selank has been associated with rapid upregulation of brain-derived neurotrophic factor (BDNF) expression in hippocampal tissue, including in models of glucocorticoid-induced BDNF suppression. BDNF upregulation is proposed to contribute to Selank’s nootropic effects on memory formation and learning processes observed in rodent behavioural models. The relationship between hippocampal BDNF induction and the anxiolytic profile is under ongoing investigation in preclinical systems.

Monoaminergic and Serotonin System Interactions

In rodent brain preparations, Selank treatment has been associated with modulation of serotonin metabolism, including induction of serotonin catabolism in specific brain regions and modulation of monoamine neurotransmitter concentrations [Semenova et al., 2009]. Effects on dopaminergic and noradrenergic systems have also been characterised in rodent in vivo preparations, contributing to the compound’s antidepressant-like and antistress profiles in preclinical models.

Immunomodulatory Activity

Selank retains the immunomodulatory activity of its parent tuftsin sequence. In isolated cell preparations and rodent models, Selank has been shown to modulate interleukin-6 (IL-6) expression and influence T helper cell cytokine balance. Modulation of chemokine and cytokine gene expression has been characterised following single and repeated administration in murine spleen preparations.

Key Research Findings

In preclinical and clinical research contexts, Selank (and by structural inference N-Acetyl Selank) has been associated with the following observations. Unless otherwise noted, findings are derived from Selank studies; direct N-Acetyl Selank data are not yet available in peer-reviewed literature.

• Enkephalinase inhibition: Selank dose-dependently inhibited plasma enkephalin hydrolysis (IC50: 15 μM) with greater potency than standard peptidase inhibitors; reduced enkephalin half-life observed in patients with generalised anxiety disorder [Zozulya et al., 2001].
• Anxiolytic activity vs benzodiazepine: In a clinical study of 62 patients with GAD and neurasthenia, Selank’s anxiolytic effects were comparable to medazepam, with additional antiasthenic and psychostimulant effects; no sedation or dependence was observed [Zozulya et al., 2008].
• BDNF upregulation: Intranasal Selank administration is associated with rapid BDNF expression increase in rat hippocampal tissue, including reversal of glucocorticoid-induced BDNF suppression in rodent models.
• GABAergic gene expression: Transcriptomic analysis in rat hippocampal preparations identified changes in GABA-A receptor subunit gene expression following Selank administration; proposed as a non-benzodiazepine GABAergic modulation mechanism.
• Serotonin metabolism: Selank modulated serotonin metabolism in rat brain preparations, including interactions with catecholamine and monoamine systems in preclinical behavioural models [Semenova et al., 2010].

All findings listed above are derived from preclinical in vivo rodent model data or clinical studies of Selank. No peer-reviewed human clinical trial data or preclinical data have been established specifically for N-Acetyl Selank. These observations do not constitute evidence of efficacy or safety in any human condition or organism.

What are the Potential Research Applications of N-Acetyl Selank?

In controlled laboratory environments, N-Acetyl Selank and its parent compound Selank have been investigated for the following research applications. These are observed in preclinical and clinical contexts and do not constitute claims of efficacy or safety for research-grade material outside approved protocols.

Enkephalinase Inhibition and Endogenous Opioid Peptide Studies N-Acetyl Selank is employed in studies characterising the relationship between enkephalinase inhibition and endogenous opioid peptide half-life in plasma and brain tissue preparations. Research examines how N-terminal acetylation modifies aminopeptidase susceptibility relative to parent Selank in in vitro stability assays.

GABAergic Pathway Modulation Research. In isolated neural cell preparations and rodent brain preparations, N-Acetyl Selank is investigated for its capacity to modulate GABA-A receptor subunit gene expression and GABAergic inhibitory tone through pathways distinct from benzodiazepine allosteric modulation. Transcriptomic approaches are employed to characterise hippocampal and cortical GABAergic signalling responses.

BDNF Expression and Neuroplasticity Studies. N-Acetyl Selank is used in rodent models and isolated hippocampal preparations to investigate BDNF expression dynamics under stress, glucocorticoid exposure, and normal conditions. Research examines the relationship between tuftsin-analogue peptide administration, hippocampal neurotrophin levels, and cognitive performance markers in preclinical paradigms.

Anxiolytic Peptide Pharmacology and SAR Studies. As a structurally modified Selank derivative, N-Acetyl Selank is employed in comparative studies examining how N-terminal acetylation alters metabolic stability, receptor affinity, and pharmacological activity profiles relative to the parent compound. These SAR investigations inform the development of metabolically optimised neuropeptide research tools.

Tuftsin-Analogue Immunomodulatory Research. In isolated cell preparations, N-Acetyl Selank is investigated for immunomodulatory activity through its tuftsin-derived sequence, including effects on cytokine expression profiles, IL-6 modulation, and T helper cell cytokine balance — research applications inherited from the parent tuftsin structure.

What are the Potential Side Effects of N-Acetyl Selank?

Researchers in preclinical and clinical settings have noted the following observations for Selank: no direct toxicity or adverse effect data have been published for N-Acetyl Selank specifically.

• No sedation, cognitive impairment, or dependence observed in clinical studies of Selank at anxiolytic doses; no withdrawal syndrome observed in clinical research populations — contrasting with benzodiazepine class effects
• No significant toxicity reported in preclinical rodent studies of Selank at research-relevant doses
• Intranasal administration of Selank was well-tolerated in clinical study populations; injection site reactions were not characterised for N-Acetyl Selank specifically
• Immunomodulatory activity via tuftsin-derived sequence may produce cytokine profile changes in cell-based research systems, relevant as a confounding variable in immunology model experiments
• No human safety or tolerability data have been established for N-Acetyl Selank. Observations above are derived from parent Selank studies and should not be directly extrapolated to N-Acetyl Selank or to human or animal outcomes outside of clinical trial contexts.

Risk & Handling

Handling Precautions

N-Acetyl Selank should only be handled by trained laboratory personnel familiar with synthetic neuropeptide research compounds. Appropriate personal protective equipment is required: nitrile gloves, a laboratory coat, and eye protection at a minimum. When working with lyophilized powder, use within a laminar flow cabinet or clean area to avoid inhalation of particulate matter. Avoid aerosol generation during reconstitution.

Exposure Risks

Risk Tier: LOW–MODERATE

N-Acetyl Selank is expected to share Selank’s generally low acute toxicity profile based on structural similarity. Selank has not produced significant toxicity in preclinical studies at research-relevant doses. The compound’s multi-pathway CNS activity — enkephalinase inhibition, GABAergic modulation, monoaminergic interactions — means that accidental systemic exposure could produce pharmacological effects in tissues expressing relevant targets. No human safety or tolerability data have been established for N-Acetyl Selank.

Storage

• Lyophilized form: Store at −20°C in original sealed, light-protected container with desiccant
• Reconstituted form: Store at 4°C; use within 48–72 hours of reconstitution
• Do not subject to repeated freeze-thaw cycles; peptide integrity may be compromised
• Protect from prolonged light exposure and moisture
• The N-terminal acetylation is designed to enhance stability; standard peptide storage precautions nonetheless apply

Frequently Asked Questions

Q: What is N-Acetyl Selank, and what is it investigated for in research? A: N-Acetyl Selank is a synthetic N-terminally acetylated derivative of Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro), a tuftsin-analogue heptapeptide. It is investigated in preclinical research contexts for GABAergic pathway modulation, enkephalinase inhibition, BDNF expression dynamics, and monoaminergic system interactions, based on the parent compound’s established pharmacological profile. Specific peer-reviewed data for N-Acetyl Selank is limited; most mechanistic data derive from Selank studies. It is not approved by the FDA for human use and is intended strictly for laboratory and research purposes.

Q: How does N-Acetyl Selank differ from Selank? A: Selank (TKPRPGP; MW 751.887 g/mol; CAS 129954-34-3) is the parent compound. N-Acetyl Selank adds an acetyl group to the N-terminus (Ac-TKPRPGP; MW ~793.93 g/mol; PubChem CID 133082488), increasing resistance to aminopeptidase-mediated degradation from the N-terminus. The acetylation is hypothesised to extend the compound’s effective half-life in biological matrices. No peer-reviewed comparative pharmacology data between Selank and N-Acetyl Selank in preclinical models has been published at the time of this writing.

Q: What is the mechanism of Selank’s enkephalinase inhibition? A: In plasma and brain tissue preparations, Selank dose-dependently inhibits enkephalin-degrading enzymes (enkephalinases), with an IC50 of 15 μM. This inhibition preserves endogenous leucine- and methionine-enkephalin concentrations by reducing their enzymatic hydrolysis rate, thereby prolonging enkephalin-mediated inhibitory signalling. Patients with GAD were observed to have shortened enkephalin half-life and reduced enkephalinase activity, consistent with a role for enkephalin system dysregulation in anxiety pathophysiology [Zozulya et al., 2001].

Q: Is there dedicated clinical research for N-Acetyl Selank? A: No dedicated peer-reviewed clinical research has been published for N-Acetyl Selank. Available clinical data pertains to the parent compound Selank, including a clinical study comparing Selank to medazepam in 62 patients with GAD and neurasthenia [Zozulya et al., 2008] and a comparative study against phenazepam [Medvedev et al., 2014]. N-Acetyl Selank’s acetylated structure is expected to share Selank’s pharmacological profile with enhanced metabolic stability, but this has not been directly demonstrated in published research.

Q: How should N-Acetyl Selank be stored? A: Lyophilized N-Acetyl Selank should be stored at −20°C in a sealed, light-protected container with desiccant. Once reconstituted, the solution should be stored at 4°C and used within 48–72 hours. Repeated freeze-thaw cycles are not recommended. The N-terminal acetylation provides enhanced aminopeptidase resistance, but standard lyophilized peptide storage precautions apply to maintain full compound integrity.

Q: What toxicity observations have been reported for Selank in preclinical and clinical studies? A: Selank has not produced significant toxicity in preclinical rodent studies at research-relevant doses. In clinical studies, Selank was well tolerated with no sedation, amnesia, or dependence observed — a key differentiating feature from benzodiazepine-class anxiolytics. No dedicated toxicity data for N-Acetyl Selank has been published. No human safety or tolerability data have been established for N-Acetyl Selank. Observations should not be extrapolated to human or animal outcomes.

Related Research Compounds

Researchers investigating N-Acetyl Selank may also be interested in the following compounds currently available for laboratory research at RCDbio:

• Selank — The parent heptapeptide (TKPRPGP) for which the primary mechanistic and clinical data exists; serves as the primary reference compound for N-Acetyl Selank comparative stability and pharmacology studies.
• N-Acetyl-Semax — An N-terminally acetylated derivative of Semax, a synthetic ACTH(4-10) analogue; shares the N-terminal acetylation modification strategy and is commonly investigated alongside N-Acetyl Selank in comparative neuropeptide stability research.

All products listed are for laboratory and research purposes only.

References

1. Zozulya, A. A., Kost, N. V., Sokolov, O. Yu., Gabaeva, M. V., Grivennikov, I. A., Andreeva, L. N., Zolotarev, Y. A., Ivanov, S. V., Andryushchenko, A. V., Myasoedov, N. F., & Smulevich, A. B. (2001). The inhibitory effect of Selank on enkephalin-degrading enzymes as a possible mechanism of its anxiolytic activity. Bulletin of Experimental Biology and Medicine, 131(4), 315–317. https://pubmed.ncbi.nlm.nih.gov/11550013/

2. Zozulya, A. A., Neznamov, G. G., Siuniakov, T. S., Kost, N. V., Gabaeva, M. V., Sokolov, O. Yu., Serebriakova, E. V., Siranchieva, O. A., Andriushenko, A. V., Telesheva, E. S., Siuniakov, S. A., Smulevich, A. B., Myasoedov, N. F., & Seredenin, S. B. (2008). Efficacy and possible mechanisms of action of a new peptide anxiolytic, Selank, in the therapy of generalized anxiety disorders and neurasthenia. Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 108(4), 38–48. https://pubmed.ncbi.nlm.nih.gov/18454096/

3. Semenova, T. P., Kozlovskiy, I. I., Zakharova, N. M., & Kozlovskaya, M. M. (2010). Experimental optimization of learning and memory processes by Selank. Eksperimental’naya i Klinicheskaya Farmakologiya, 73(8), 2–5. https://pubmed.ncbi.nlm.nih.gov/20919548/

4. Medvedev, V. E., Tereshchenko, O. N., Israelian, A. Yu., Chobanu, I. K., Kost, N. V., Sokolov, O. Yu., & Myasoedov, N. F. (2014). A comparison of the anxiolytic effect and tolerability of Selank and phenazepam in the treatment of anxiety disorders. Zhurnal Nevrologii i Psikhiatrii imeni S.S. Korsakova, 114(7), 17–22. https://pubmed.ncbi.nlm.nih.gov/25176261/ 

Disclaimer

N-Acetyl Selank is exclusively for laboratory research purposes. RCDbio products are not intended to diagnose, prevent, treat, or cure any disease or medical condition.

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