A practical reference on Selank: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-04-06 and is reviewed periodically as new material appears.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Derived from the seven-residue sequence |
| Molecular weight | About 751.9 g/mol | Average mass; the monoisotopic value is slightly lower |
| Residue count | Seven amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | Selank extends tuftsin at the C-terminus |
| Compound class | Synthetic short peptide | Studied in a research setting; not a licensed drug in most markets |
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Also, there is no surface tension in a supercritical fluid, as there is no liquid/gas phase boundary. By changing the pressure and temperature of the fluid, the properties can be "tuned" to be more liquid-like or more gas-like. One of the most important properties is the solubility of material in the fluid. Solubility in a supercritical fluid tends to increase with density of the fluid (at constant temperature). Since density increases with pressure, solubility tends to increase with pressure. The relationship with temperature is a little more complicated. At constant density, solubility will increase with temperature. However, close to the critical point, the density can drop sharply with a slight increase in temperature. Therefore, close to the critical temperature, solubility often drops with increasing temperature, then rises again.
However, unique cultural-specific phenotypes of disordered eating emerged prior to Western influence. For example, restrictive eating patterns were found in Japan as early as the 18th century and fewer reports of eating disorders were found between 1868 and 1944, when rapid Westernization occurred. Sex-specific stressors and cultural dynamics could be implicated in this independent development of anorexia nervosa symptomology.
You see, we were having negotiations with these lunatics, and it was my opinion that they [the Iranians] were going to attack first." On April 2, US president Trump stated he does not "care" about Iran's stock of highly enriched uranium (HEU) as it is underground, contradicting a key rationale he brought up when starting the war. In fact, Iran's HEU stock is now assessed as a more risky scenario than before the war began, as it would leave Iran significantly closer to the capability of making nuclear bombs than the proposed settlement being negotiated in Geneva two days before the war began. Iran's development of HEU stockpile itself is the consequence of Trump's decision in 2018 to withdraw from a multilateral nuclear deal. Another reason given by the Trump administration for initiating the war was the desire to seize Iran's oil and gas resources. According to the political scientist Vali Nasr, Trump aspired to become the American president who finally resolved the Iran problem.
Control of petroleum production has been a significant driver of international relations during much of the 20th and 21st centuries. Organizations like OPEC have played an outsized role in international politics. Some historians and commentators have called this the "Age of Oil" With the rise of renewable energy and addressing climate change some commentators expect a realignment of international power away from petrostates.
Posttranslational modifications, especially site-specific phosphorylation mediated either by upstream kinases or by intramolecular autophosphorylation, have been demonstrated to reversibly modulate CK1δ kinase activity. Several residues within the C-terminal regulatory domain of CK1δ were identified as targets for autophosphorylation, including Ser-318, Thr-323, Ser-328, Thr-329, Ser-331, and Thr-337. Upon autophosphorylation sequence motifs within the C-terminal domain are generated, which are able to block the catalytic center of the kinase by acting as a pseudosubstrate. Regulatory function of the C-terminal domain has furthermore been confirmed by the observation that kinase activity is increased after proteolytic cleavage of this domain. Besides autophosphorylation, site-specific phosphorylation by other cellular kinases has been demonstrated to regulate kinase activity. So far, C-terminal phosphorylation of CK1δ by upstream kinases has been confirmed for protein kinase A (PKA), protein kinase B (Akt), cyclin-dependent kinase 2/cyclin E (CDK2/E) and cyclin-dependent kinase 5/p35 (CDK5/p35), CDC-like kinase 2 (CLK2), protein kinase C α (PKCα), and checkpoint kinase 1 (Chk1). For several phosphorylation events also effects on kinase function have been described. For residue Ser-370, which can be phosphorylated at least by PKA, Akt, CLK2, PKCα and Chk1, major regulatory function has been demonstrated.
Sources: en.wikipedia.org
== Side effects == One of the most common side effects of spironolactone is frequent urination. Other general side effects include dehydration, hyponatremia (low sodium levels), mild hypotension, ataxia (muscle incoordination), drowsiness, dizziness, dry skin, and rashes. Because of its antiandrogenic activity, spironolactone can cause breast tenderness, gynecomastia (breast development), feminization in general, and demasculinization, as well as sexual dysfunction including loss of libido and erectile dysfunction, although these side effects are usually confined to high doses. At very high doses (400 mg/day), spironolactone has also been associated with testicular atrophy and reversibly reduced fertility, including semen abnormalities, such as decreased sperm count and motility in men, but such doses of spironolactone are rarely used clinically. In women, spironolactone can cause menstrual irregularities, breast tenderness, and breast enlargement. Aside from these adverse effects, the side effects of spironolactone in women taking high doses are minimal, and it is well tolerated. A potential side effect of spironolactone is hyperkalemia (high potassium levels), which in severe cases, can be life-threatening. Hyperkalemia can present as a normal anion-gap metabolic acidosis. The addition of spironolactone to loop diuretics in people with heart failure reportedly was associated with a higher risk of hyperkalemia and acute kidney injury. Spironolactone may put people at a heightened risk for gastrointestinal issues such as nausea, vomiting, diarrhea, cramping, and gastritis.
=== 13 May === Moments before Ukraine's entry to the Eurovision Song Contest 2023, Tvorchi, were due to perform in Liverpool in the United Kingdom, their hometown of Ternopil was struck by Russian missiles, injuring two people and damaging warehouses. This prompted them to close their performance with a message for solidarity with Ukraine. 11 people were also injured in overnight drone attacks in Khmelnytskyi. The Ukrainian military said that 18 out of 22 Iranian Shahed-131/136 drones were shot down in the attacks. Russia accused Ukraine of attacking the occupied city of Luhansk with its newly acquired British Storm Shadow missiles, wounding six children. It also claimed to have downed two Ukrainian aircraft, an Su-24 and a MiG-29, that launched the missiles. The Russian Defence Ministry said that Russian forces had seized a block in Bakhmut. Two Russian helicopters, both Mi-8s, and two Russian fighters, an Su-34 and an Su-35, crashed in Bryansk Oblast, near the border with Ukraine with no survivors. Nine personnel were said to have been killed. The Russian newspaper Kommersant reported that the aircraft were on their way for a bombing run in neighboring Chernihiv Oblast when they were shot down by Ukrainian forces, which was also echoed by Russian pro-military bloggers. The Russian state news agency TASS only reported the loss of an Su-34 warplane without providing a reason, as well as that of a helicopter due to an engine fire near Klintsy, about 40 km (25 mi) from the international border.
=== Mechanism of action === Heparin binds to the enzyme inhibitor antithrombin (AT), causing a conformational change that results in its activation through an increase in the flexibility of its reactive site loop. The activated AT then inactivates thrombin, factor Xa and other proteases. The rate of inactivation of these proteases by AT can increase by up to 1000-fold due to the binding of heparin. Heparin binds to AT via a specific pentasaccharide sulfation sequence contained within the heparin polymer:
=== mzData === mzData was the first attempt by the Proteomics Standards Initiative (PSI) from the Human Proteome Organization (HUPO) to create a standardized format for Mass Spectrometry data. This format is now deprecated, and replaced by mzML.
Sources: en.wikipedia.org
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.
Tuftsin contains four residues, while selank carries an additional Pro-Gly-Pro segment at the carboxyl end. That extension is intended to reduce enzymatic cleavage. Comparative pharmacokinetic data in humans remain limited.
No single receptor target is widely accepted as the definitive mediator of the reported effects. Proposed contributors include GABAergic modulation, shifts in monoamine turnover, and altered neuropeptide degradation. The mechanism is treated in the literature as unresolved.
Reports describe modulation of GABA signalling, changes in monoamine turnover and effects on neurotrophic factor expression. These observations come mainly from animal and cell studies. A single unifying mechanism has not been demonstrated.