Everything below concerns Research chemical. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-12-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
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 synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
| 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 |
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.
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.
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.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
=== The Buck Institute for Research on Aging === In November 2016, Verdin became president and CEO of the Buck Institute for Research on Aging. The Buck Institute is the first independent research center focused solely on aging. As of 2022, it had an operating budget of $65 million a year and around 300 employees. The Buck's first human clinical trial, Buck Institute Ketone Ester (BIKE), was announced in 2023. In 2025, Verdin was named a scientific ambassador for Alliance for Longevity Science, Arts & Entertainment (ALSAE), a partner organization of the Buck Institute.
== Signs and symptoms == The lesion is usually painless. The usual appearance is of two excess tissue folds in alveolar vestibule/buccal sulcus, with the flange of the denture fitting in between the two folds. It may occur in either the maxillary or mandibular sulci, although the latter is more usual. Anterior locations are more common than posterior. Less commonly there may be a single fold, and the lesion may appear on the lingual surface of the mandibular alveolar ridge. The swelling is firm and fibrous, with a smooth, pink surface. The surface may also show ulceration or erythema. The size of the lesion varies from less than 1 cm to involving the entire length of the sulcus.
== Society and culture == The American TV show, Diagnosis, in episode 1 Detective Work, an athletic 23-year-old nursing student, Angel Parker, experiences episodes of extreme muscle fatigue, pain and cramping after prolonged exercise, sometimes followed by dark urine (myoglobinuria) and elevated CK (rhabdomyolysis). These episodes can leave her immobile for hours. She had experienced muscle pains since childhood, passed-off as "growing pains." Her first hospitalization was at age 14, for intolerable leg pain that woke her in the middle of the night, sobbing uncontrollably from the intense pain. After multiple hospitalizations for myoglobinuria and rhabdomyolysis, many misdiagnoses, and many different doctors and tests that were unable to give an explanation for her symptoms, through the assistance of the show genetic sequencing confirmed that she had CPT-II deficiency (a fatty-acid metabolism disorder). In 2010, Walk over Wales (WoW), the first walking course for those with muscle glycogen storage disease occurred to teach participants activity adaptations, swap notes, and raise public awareness. Led by Andrew Wakelin, participants came from around the world, including Stacey Reason, Dan Chambers, Andy Williams, Charlton Thear and Dr. Ros Quinlivan. From Great Orme to Cardiff Bay, in 32 days they walked 210 miles (338 km) and ascended approximately 35,000 feet (10,700 metres) through Snowdonia National Park, the Cambrian Mountains, and Brecon Beacons National Park.
Dimethyl trisulfide (DMTS) is an organic chemical compound and the simplest organic trisulfide, with the chemical formula CH3SSSCH3. It is a flammable liquid with a foul odor, which is detectable at levels as low as 1 part per trillion.
Sources: en.wikipedia.org
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they are able to interact with neurotransmitter receptors on the target cell. Some neurotransmitters are also stored in large dense core vesicles. The neurotransmitter's effect on the target cell is determined by the receptor it binds to. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available and often require a small number of biosynthetic steps for conversion. Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified. Common neurotransmitters include glutamate, GABA, acetylcholine, glycine, dopamine and norepinephrine.
Turin, as the former capital of the Kingdom of Sardinia and the Kingdom of Italy, is home of the Savoy Residences. In addition to the 17th-century Royal Palace, built for Madama Reale Christine Marie of France (the official residence of the Savoys until 1865) there are many palaces, residences and castles in the city centre and in the surrounding towns. Turin is home to Palazzo Chiablese, the Royal Armoury, the Royal Library, Palazzo Madama, Palazzo Carignano, Villa della Regina, and the Valentino Castle. The complex of the Residences of the Royal House of Savoy in Turin and in the nearby cities of Rivoli, Moncalieri, Venaria Reale, Agliè, Racconigi, Stupinigi, Pollenzo and Govone was declared a World Heritage Sites by UNESCO in 1997. UNESCO also recognises Turin as a "Design City." In recent years, Turin has become an increasingly popular tourist destination, ranking 203rd in the world and tenth in Italy in 2008, with about 240,000 tourist arrivals. The Egyptian Museum of Turin specialises in archaeology and anthropology, in particular the art of ancient Egypt. It is home to what is regarded as one of the largest collections of Egyptian antiquities outside of Egypt. In 2006 it received more than 500,000 visitors. The Museum of Oriental Art houses one of the most important Asian art collections in Italy. Other museums include the National Museum of Cinema, the Museo Nazionale dell'Automobile, the J-Museum, the Museum of Human Anatomy Luigi Rolando, the Museo delle Marionette (puppet museum) and the Museo Nazionale della Montagna (National Museum of the Mountains).
At cytoplasmic conditions, where the ADP/ATP ratio is 10 orders of magnitude from equilibrium, the ΔG is around −57 kJ/mol. Along with pH, the free energy change of ATP hydrolysis is also associated with Mg2+ concentration, from ΔG°' = −35.7 kJ/mol at a Mg2+ concentration of zero, to ΔG°' = −31 kJ/mol at [Mg2+] = 5 mM. Higher concentrations of Mg2+ decrease free energy released in the reaction due to binding of Mg2+ ions to negatively charged oxygen atoms of ATP at pH 7.
Within a three months period in 1980, at least ten Libyan dissidents were murdered in Europe, including ex-diplomats, ex-army officers, businessmen, journalists, and student activists in disparate locations such as London, Greece and Austria. At least eleven more were assassinated in 1981. In 1984, Gaddafi was tricked by Egyptian President Hosni Mubarak into announcing the assassination of former Libyan Prime Minister Abdul Hamid al-Bakkoush in Cairo; Bakkhoush not only turned up alive but held a press conference with Egypt's Interior Minister. In 1979, Gaddafi created the Islamic Legion, through which several thousand Africans were military trained. Libya had sought to improve US relations under President Jimmy Carter, for instance by courting his brother, businessman Billy Carter, and paying for the services of former CIA officers, but in 1979 the US placed Libya on its list of "State Sponsors of Terrorism". Relations were further damaged when a demonstration torched the US embassy in solidarity with the perpetrators of the Iran hostage crisis. Libyan fighters began intercepting US fighter jets flying over the Mediterranean, signalling the collapse of relations between the countries. Italian media have alleged that the Itavia Flight 870 was shot down during a dogfight involving Libyan, United States, French and Italian Air Force fighters in an assassination attempt by NATO members on a Libyan politician, perhaps even Gaddafi, flying in the same airspace.
==== MeSH D12.125.072 – amino acids, cyclic ==== MeSH D12.125.072.050 – amino acids, aromatic MeSH D12.125.072.050.342 – dextrothyroxine MeSH D12.125.072.050.685 – phenylalanine MeSH D12.125.072.050.685.400 – dihydroxyphenylalanine MeSH D12.125.072.050.685.400.180 – cysteinyldopa MeSH D12.125.072.050.685.400.500 – levodopa MeSH D12.125.072.050.685.400.600 – methyldopa MeSH D12.125.072.050.685.440 – fenclonine MeSH D12.125.072.050.685.450 – p-fluorophenylalanine MeSH D12.125.072.050.685.500 – melphalan MeSH D12.125.072.050.767 – thyroxine MeSH D12.125.072.050.767.741 – thyronines MeSH D12.125.072.050.767.741.180 – diiodothyronines MeSH D12.125.072.050.767.741.894 – triiodothyronine MeSH D12.125.072.050.767.741.947 – triiodothyronine, reverse MeSH D12.125.072.050.850 – tryptophan MeSH D12.125.072.050.850.479 – 5-hydroxytryptophan MeSH D12.125.072.050.875 – tyrosine MeSH D12.125.072.050.875.064 – betalains MeSH D12.125.072.050.875.064.500 – betacyanins MeSH D12.125.072.050.875.130 – dihydroxyphenylalanine MeSH D12.125.072.050.875.130.180 – cysteinyldopa MeSH D12.125.072.050.875.130.500 – levodopa MeSH D12.125.072.050.875.130.600 – methyldopa MeSH D12.125.072.050.875.262 – diiodotyrosine MeSH D12.125.072.050.875.379 – melanins MeSH D12.125.072.050.875.496 – monoiodotyrosine MeSH D12.125.072.050.875.664 – methyltyrosines MeSH D12.125.072.050.875.664.050 – alpha-methyltyrosine MeSH D12.125.072.050.875.750 – phosphotyrosine MeSH D12.125.072.170 – cycloleucine MeSH D12.125.072.200 – desmosine MeSH D12.125.072.329 – histidine MeSH D12.125.072.329.269 – ergothioneine MeSH D12.125.072.329.539 – methylhistidines MeSH D12.125.072.401 – imino acids MeSH D12.125.072.401.200 – azetidinecarboxylic acid MeSH D12.125.072.401.623 – proline MeSH D12.125.072.401.623.270 – captopril MeSH D12.125.072.401.623.374 – fosinopril MeSH D12.125.072.401.623.478 – hydroxyproline MeSH D12.125.072.401.761 – pyrrolidonecarboxylic acid MeSH D12.125.072.401.830 – technetium tc 99m diethyl-iminodiacetic acid MeSH D12.125.072.401.840 – technetium tc 99m disofenin MeSH D12.125.072.401.900 – technetium tc 99m lidofenin MeSH D12.125.072.415 – isodesmosine
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.
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.