If you have been reading about TP-7 and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2025-11-27. Numbers and descriptions here follow the published literature rather than marketing material.
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
| Property | Value | Notes |
|---|---|---|
| Route studied | Intranasal | Predominant route in published reports |
| Circulation stability | Short, minutes scale | Peptidases cleave it; the tail slows the process |
| Analytical method | RP-HPLC with mass spectrometry | Used for identity and purity assessment |
| Reported outcome domains | Anxiety and cognitive measures | Derived from small, mostly regional trials |
| Regulatory status | Marketed in Russia | Availability outside that market is limited |
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is 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.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres is the standard purity method. Mass spectrometry, typically electrospray ionisation, confirms identity through the expected mass-to-charge pattern. Amino acid analysis can verify composition independently. Chiral purity requires separate techniques such as derivatisation followed by chromatographic separation, and such data are rarely reported for research-grade material.
Quantification in biological matrices relies on liquid chromatography coupled to tandem mass spectrometry with stable-isotope internal standards. Low plasma concentrations and adsorption to container surfaces both complicate measurement. Solid-phase extraction is often needed to reduce matrix interference before injection. Reported limits of quantification differ widely between laboratories, which makes direct comparison of pharmacokinetic results difficult and limits meta-analysis.
Hours after Palacios' statement, Free Peru's General Secretary Vladimir Cerrón said "When you lose faith in your militancy, you force yourself to look for strength with the mercenaries." Cerron also quoted Borges by saying "traitors are reliable because they never change." Afterward, El Comercio released a paper claiming that the Free Peru caucus voted as a split group nearly 50% of the time. On 29 November 2021, Vladimir Cerrón announced that Free Peru would hold an extraordinary national assembly on 5 December 2021, to determine the party's stance on the impeachment motion, the government, and other topics. On 6 December 2021, Free Peru concluded its extraordinary national assembly by announcing that it would vote unanimously against impeachment. Free Peru stated that it has "serious discrepancies" with the "caviar" government of Castillo, but also accused the pro-impeachment movement of being fascist and anti-democratic. Additionally, Free Peru also reaffirmed that it considered Cuba, Venezuela, and Bolivia to have democratic governments.
== Early life and education == Strahl was born in Buffalo, New York and raised in Albuquerque, New Mexico. He moved to Chapel Hill, North Carolina in 1980 when his father went to medical school at the University of North Carolina at Chapel Hill. Strahl entered the University of North Carolina at Greensboro in 1988, where he double majored in Chemistry and Biology. Strahl joined the Department of Biochemistry at North Carolina State University and received his PhD in 1998 under the supervision of Dr. William L. Miller. At North Carolina State University, Strahl defined mechanisms for how the Follicle-Stimulating Hormone-Beta (FSHß) gene is regulated at the transcriptional level. In 1998, Strahl performed postdoctoral studies under the mentorship of Dr. C. David Allis at the University of Virginia’s Department of Biochemistry and Molecular Genetics.
Tegileridine, sold under the brand name Aisute, is a drug which acts as a μ-opioid receptor agonist. It is closely related to compounds such as oliceridine, TRV734, and SHR9352, and shares a similar profile as a biased agonist selective for activation of the G protein signalling pathway over β-arrestin2 recruitment. In January 2024, tegileridine was approved in China under the brand name Aisute for the treatment of moderate to severe pain after abdominal surgery.
=== Food === Protein hydrolysis release savory free amino acids (especially glutamic acid) and peptides. Hydrolyzed vegetable protein and yeast extract are commonly used as flavor enhancers (sources of umami) as a result. The non-protein components in these products also contribute to the flavor. Protein hydrolysis also increases their digestibility and rate of digestion. Some hydrolyzed beef protein powders are used for specialized diets for athletes. Protein hydrolysis can be used to destroy epitopes involved in recognition by antibodies involved in allergy. "An allergen must have at least 2 IgE-binding epitopes, and each epitope must be at least 15 amino acid residues long, to trigger a type 1 hypersensitivity reaction." As a result, it has been used to reduce the allergenicity of infant formula: Reducing the size of cow milk proteins in the formula makes it more suitable for consumption by babies suffering from milk protein intolerance. The US FDA has approved a label for this usage of partially-hydrolyzed proteins in 2017, but a meta-analysis published the same year shows insufficient evidence for this use.
The capacity of mammalian species to detoxify the carcinogenic chemical benzo[a]pyrene to a water-soluble form also correlates well with maximum life span. Short-term induction of oxidative stress due to calorie restriction increases life span in Caenorhabditis elegans by promoting stress defense, specifically by inducing an enzyme called catalase. As shown by Michael Ristow and co-workers nutritive antioxidants completely abolish this extension of life span by inhibiting a process called mitohormesis.
Sources: en.wikipedia.org
The primitive gut is suspended from the posterior abdominal wall by the dorsal mesentery. The gastrointestinal tract and associated dorsal mesentery are subdivided into foregut, midgut, and hindgut regions based on the respective blood supply. The foregut is supplied by the celiac trunk, the midgut is supplied by the superior mesenteric artery (SMA), and the hindgut is supplied by the inferior mesenteric artery (IMA). This division is established by the fourth week of development. After this, the midgut undergoes a period of rapid elongation, forcing it to herniate through the navel. During herniation, the midgut rotates 90° anti-clockwise around the axis of the SMA and forms the midgut loop. The cranial portion of the loop moves to the right and the caudal portion of the loop moves toward the left. This rotation occurs at about the eighth week of development. The cranial portion of the loop will develop into the jejunum and most of the ileum, while the caudal part of the loop eventually forms the terminal portion of the ileum, the ascending colon and the initial two-thirds of the transverse colon. As the foetus grows larger, the mid-gut loop is drawn back through the umbilicus and undergoes a further 180° rotation, completing a total of 270° rotation. At this point, about 10 weeks, the caecum lies close to the liver. From here it moves in a cranial to caudal direction to eventually lie in the lower right portion of the abdominal cavity.
Other common symptoms which come on rapidly include neuromuscular symptoms, shock, loss of consciousness, hypotension, pallor, ataxia, excessive salivation (oral secretions may become profuse and thick), limb paralysis, nausea and vomiting, ptosis, fever, and severe abdominal pain. Local tissue damage appears to be relatively infrequent and of minor severity in most cases of black mamba envenomation. Edema is typically minimal. Acute kidney injury has been reported in a few cases of black mamba bites in humans as well as in animal models. Death is due to suffocation resulting from paralysis of the respiratory muscles. Untreated black mamba bites have a mortality rate of 100%. Antivenom therapy is the mainstay of treatment for black mamba envenomation. A polyvalent antivenom produced by the South African Institute for Medical Research (SAIMR) is used to treat all black mamba bites from different localities. Because of the availability of antivenom, a bite from a black mamba no longer results in certain death, but in order for the antivenom therapy to be successful, vigorous treatment and large doses of antivenom must be administered rapidly post-envenomation. In case studies of black mamba envenomation, respiratory paralysis has occurred in less than 15 minutes. Envenomation by this species invariably causes severe neurotoxicity because black mambas often strike repeatedly in a single lunge. The doses of antivenom required are often massive (10–30+ vials) for bites from this species.
The two substrates of this enzyme are D-threitol and oxidised nicotinamide adenine dinucleotide phosphate (NADP+). Its products are D-erythrulose, reduced NADPH, and a proton. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is erythritol:NADP+ oxidoreductase. This enzyme is also called D-erythrulose reductase.
The aorta is the root systemic artery (i.e., main artery). In humans, it receives blood directly from the left ventricle of the heart via the aortic valve. As the aorta branches and these arteries branch, in turn, they become successively smaller in diameter, down to the arterioles. The arterioles supply capillaries, which in turn empty into venules. The first branches off of the aorta are the coronary arteries, which supply blood to the heart muscle itself. These are followed by the branches of the aortic arch, namely the brachiocephalic artery, the left common carotid, and the left subclavian arteries.
Sources: en.wikipedia.org
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.
Intranasal delivery is the route described in most published work. It is used because the peptide is degraded quickly once it reaches circulation. Direct evidence of brain penetration in humans is lacking.
Most trials are small, regionally concentrated, and often lack rigorous blinding or placebo control. Independent replication is limited. Reviews in English generally rate the evidence as preliminary.
Reverse-phase HPLC is the usual method and gives a percentage purity value. Mass spectrometry then confirms the molecular mass. Together they provide a basic identity and purity profile for a lot.