Everything below concerns tuftsin. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-11-28. Numbers and descriptions here follow the published literature rather than marketing material.
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analog of the tetrapeptide tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Reported consistently across pharmacopoeial descriptions |
| Appearance | White to off-white lyophilized powder | Typical form of research-grade material |
| Solubility | Freely soluble in water | Aqueous buffers; poor in nonpolar solvents |
| Typical storage temperature | -20 degrees Celsius | Lyophilized powder; protect from moisture |
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a structural analogue of tuftsin, a naturally occurring tetrapeptide fragment of the immunoglobulin heavy chain. The added Pro-Gly-Pro tail was intended to slow enzymatic degradation and extend biological activity. In Russia it is registered as an anxiolytic nasal preparation, while regulators elsewhere have not approved it for clinical use.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
== Stereochemie == Ibuprofen liegt als 1:1-Gemisch (Racemat) des pharmakologisch wirksamen Enantiomers (Eutomer) (S)-(+)-Ibuprofen (Dexibuprofen) und des unwirksamen (R)-(−)-Ibuprofen (Distomer) vor. (R)-(−)-Ibuprofen wird im Körper durch eine Isomerase (2-Arylpropionyl-CoA-epimerase) in (S)-(+)-Ibuprofen umgewandelt. Diese Isomerisierung ist unidirektional, d. h., es findet nur eine Umwandlung von (R)-(−)-Ibuprofen in (S)-(+)-Ibuprofen statt, nicht umgekehrt. Damit scheint die Verwendung des billigeren Racemats (RS)-(±)-Ibuprofen als Arzneistoff nicht nachteilig zu sein. Allerdings werden nur 50–60 % der applizierten Menge des Distomers so isomerisiert. Zudem verläuft die Isomerisierung sehr langsam. Ein weiterer Teil des (R)-(−)-Ibuprofens wird in das Fettgewebe eingelagert und mit einer Halbwertszeit in der Größenordnung mehrerer Tage wieder freigesetzt. In klinischen Studien konnte gezeigt werden, dass 200 mg (S)-(+)-Ibuprofen in etwa ebenso wirksam sind wie 400 mg (RS)-(±)-Ibuprofen.
== Pharmakodynamik == Ibuprofen hemmt nichtselektiv die Cyclooxygenasen I und II (COX-1 und COX-2), die im Organismus für die Bildung von entzündungsvermittelnden Prostaglandinen verantwortlich sind. Daraus resultieren die Wirkungen von Ibuprofen: Es wirkt schmerzstillend (analgetisch), entzündungshemmend (antiphlogistisch) und fiebersenkend (antipyretisch) sowie hemmend auf die Schleimproduktion im Magen mit der Folge vermehrter Magenschleimhautschäden.
== Pharmakokinetik == Die Plasmahalbwertszeit beträgt etwa zwei bis drei Stunden. In geringeren Dosen (200 bis 400 mg für Erwachsene) wirkt Ibuprofen schmerzlindernd und fiebersenkend, in höheren Dosen (bis 800 mg für Erwachsene) zusätzlich entzündungshemmend. Die Resorption erfolgt hauptsächlich im Dünndarm, aber auch teilweise im Magen. Bei oraler Gabe werden nach ein bis zwei Stunden maximale Plasmaspiegel gemessen. Nach Metabolisierung in der Leber (Hydroxylierung, Carboxylierung) werden die pharmakologisch unwirksamen Metabolite vollständig, hauptsächlich (90 %) über die Nieren (renal), aber auch über die Gallenflüssigkeit (biliär) eliminiert. In einer Tierstudie mit Mäusen konnte die Bioverfügbarkeit und Wirksamkeit von Ibuprofen mit Piperin, einem Inhaltsstoff des Pfeffers, erhöht werden.
== Analytik == Die zuverlässige qualitative und quantitative Bestimmung von Ibuprofen und seinen Metaboliten in den unterschiedlichsten Untersuchungsgütern gelingt nach angemessener Probenvorbereitung durch Kopplung chromatographischer Verfahren mit der Massenspektrometrie. Unter dem Einsatz enantioselektiver Verfahren lassen sich auch die Enantiomeren des Ibuprofens trennen und quantifizieren. Auch bei ökotoxikologischen Fragen so z. B. der Untersuchung benthischer Organismen lassen sich diese Verfahren einsetzen.
Sources: de.wikipedia.org
Selank is a synthetic seven-amino-acid peptide modeled on tuftsin, a fragment of the immunoglobulin G heavy chain. It was designed in Russia to combine anxiolytic and immunomodulatory properties in one molecule.
The first four residues of Selank reproduce the tuftsin sequence Thr-Lys-Pro-Arg. A Pro-Gly-Pro extension at the C-terminus was added to slow enzymatic breakdown and extend residence time.
It holds marketing authorization in Russia, where nasal drop formulations are sold. No equivalent approval exists in the European Union, the United States, or most other countries.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.