tuftsin raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common route | Intranasal | Also injected in some animal work |
| Solubility class | Freely soluble in water | Solid form is hygroscopic |
| Typical storage | About -20 degrees Celsius | Keep desiccated and dark |
| Purity method | Reverse-phase HPLC | Reported as area percent |
| Confirmatory method | Mass spectrometry | Verifies expected molecular mass |
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.
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 with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
In 1957, Chien-Shiung Wu et al. discovered that β-decay violated parity, implying nature (the weak force) sees handedness. In the Wu experiment, researchers aligned 60Co nuclei by cooling the source to low temperatures in a magnetic field. Wu's observation was that more β-rays were emitted in the opposite direction to the nuclear spin. This asymmetry violates parity conservation.
Trelagliptin (trade name Trelaglip, Zafatek) is a pharmaceutical drug used for the treatment of type 2 diabetes (diabetes mellitus).Trelagliptin is an orally active dipeptidyl peptidase (DPP)-4 inhibitor developed by Takeda and approved in Japan and India for the treatment of type 2 diabetes mellitus. Zuventus Healthcare introduced Trelagliptin in India (2025) under the brand name Trelaglip®.
Henan Corps Hubei Corps Hunan Corps Inner Mongolia Corps Jiangsu Corps Jiangxi Corps Jilin Corps Liaoning Corps Ningxia Corps Qinghai Corps Two mobile detachments Shaanxi Corps Shanxi Corps Shandong Corps Shanghai Corps Two mobile detachments
Sources: en.wikipedia.org
== Presentation == The most characteristic symptom of acrogeria is thin, atrophic skin with mottled pigmentation and telangiectasia, most severe in the limbs and extremities. This is accompanied by easy bruising, hyperkeratosis, and a loss of subcutaneous fat, which is replaced by connective tissue. Patients have a facies with a pinched face, hollow cheeks, prominent eyes without exophthalmos, a beak-like nose and thin lips. Though the hair and nails are normal in many cases, alopecia and nail dystrophies, such as onychogryphosis and koilonychia, have been reported. Stature is short in some patients and normal in others. The general skeletal structure is unremarkable, but acrogeria results in delayed closure of the cranial sutures, notching of the mandible, and micrognathia; and may also coincide with spina bifida, clubfoot and congenital dislocation of the hips. Sexual development, including the development of secondary sex characteristics, is normal, and so is intelligence. There is no correlation of acrogeria with metabolic, opthamological or cardiovascular disorders, and patients have a normal life expectancy. Similarities between the clinical features of acrogeria and Werner's syndrome have been observed.
Communication delays during the crisis led to the establishment of the Moscow–Washington hotline to allow reliable, direct communications between the two nuclear powers. By the late 1960s, the number of ICBMs and warheads was so high on both sides that it was believed that both the United States and the Soviet Union were capable of completely destroying the infrastructure and a large proportion of the population of the other country. Thus, by some western game theorists, a balance of power system known as mutually assured destruction (or MAD) came into being. It was thought that no full-scale exchange between the powers would result in an outright winner, with at best one side emerging the pyrrhic victor. Thus both sides were deterred from risking the initiation of a direct confrontation, instead being forced to engage in lower-intensity proxy wars. During this decade the People's Republic of China began to build subterranean infrastructure such as the Underground Project 131 following the Sino-Soviet split. One drawback of the MAD doctrine was the possibility of a nuclear war occurring without either side intentionally striking first. Early Warning Systems (EWS) were notoriously error-prone. For example, on 78 occasions in 1979 alone, a "missile display conference" was called to evaluate detections that were "potentially threatening to the North American continent". Some of these were trivial errors and were spotted quickly, but several went to more serious levels.
=== Notch signaling === In 2015 and 2017, Garcia published articles in Science describing the first atomic-level visualizations of Notch signaling complexes. Garcia's group used directed evolution to strengthen low-affinity interactions between the receptor Notch1 and ligands Delta-like 4 (DLL4) and Jagged1 (Jag1) as a means of stabilizing the complexes for co-crystallization. Notch1-DLL4 and Notch1-Jag1 structures were determined by x-ray crystallography and revealed long, narrow binding interfaces assisted by multiple O-linked fucose and glucose modifications on Notch1. O-linked glycans are rarely observed at protein-protein interfaces, and their presence at the Notch-ligand interface explained how changes in glycosylation state influence Notch signaling activity. Garcia's 2017 publication also established that Notch-ligand interactions form catch bonds, and that Delta-like and Jagged ligands have different mechanical force thresholds for Notch receptor activation.
==== Cyanohydrins and cyanogenic glycosides ==== Cyanohydrins and their glycosides, referred to as cyanogenic glycosides, are widespread in nature and occur in several thousand plant species. More than one hundred naturally occurring cyanogenic glycosides have been identified. Plants utilize cyanogenic glycosides for defense and possibly also as a nitrogen storage buffer. They are biosynthesized from a limited number of amino acids and various carbohydrates. Upon tissue damage, the glycosides come into contact with enzymes (Β-glucosidase and hydroxynitrillyase), which first release the aglycone (a cyanohydrin) and subsequently cleave it into a carbonyl compound and toxic hydrocyanic acid. Amygdalin is a glycoside of mandelonitrile and one of the most widespread cyanogenic glycosides; it occurs particularly in the seeds of the rose family (Rosaceae), including cultivated apple, apricot, peach, plum, cherry, and almond tree. Whereas amygdalin is confined to the seeds of peaches, other parts of the plant predominantly contain prunasin. Prunasin is likewise a glycoside of mandelonitrile; however, its sugar moiety is a monosaccharide (rather than a disaccharide as in amygdalin). In almonds and bitter almonds, prunasin serves as a biosynthetic precursor of amygdalin. Prunasin is also present in laurel cherry. Prunasin and sambunigrin, along with several other cyanogenic glycosides, occur in passion flower; in papaya, prunasin predominates.
Sources: en.wikipedia.org
Chronic infections Chemotherapeutic & Cytotoxic drugs 5-fluorouracil Hydroxyurea Hydroxycarbamide Methotrexate Following Granulocyte colony stimulating Factor (G-CSF) administration Steroid therapy for immune thrombocytopenic purpura (ITP) Iron deficiency anaemia
A further way of carrying out glycosylation is by using enzymes, known as chemo-enzymatic glycosylation. This method is used for complex chemical synthesis. Chemical and chemo-enzymatic methods can be used for the synthesis of glycopeptides and glycoproteins. Cyclization can also be used as a method to decrease proteolytic degradation and prolong half-life, to make the peptide conformation more rigid to hinder enzymatic cleavage. This method can however lead to loss of biological function due to the reduced flexibility making the peptide inactive. For example, side chain to side chain cyclization between asparagine (position 8) and lysine (position 12), of a growth regulating factor (GRF) analogue was found to increase the half-life from 17 minutes to more than 2 hours. Another way to extend half-life do is to bind serum albumin to the peptide. Human serum albumin is the most abundant plasma protein with a molecular weight of 66.4 kDa, and it is involved in many essential bodily functions to maintain homoeostasis. As a result, albumin binding would significantly increase the molecular weight of the peptide, restricting it from being filtered into the urine by the GBM. Serum albumin has an extraordinary long half-life of 2–4 weeks which is much longer than other plasma proteins, due to it binding to the neonatal Fc receptor (FcRn). Fc receptors are proteins found on the surface of certain cells that help to protect the functions of the immune system, by binding to the Fc region of antibodies, which attach to pathogens and destroy them.
== Epidemiology == Cardiovascular disease, which is predominantly the clinical manifestation of atherosclerosis, is one of the leading causes of death worldwide. Almost all children older than age 10 in developed countries have aortic fatty streaks, with coronary fatty streaks beginning in adolescence. In 1953, a study was published that examined the results of 300 autopsies performed on U.S. soldiers who had died in the Korean War. Despite the average age of the soldiers being just 22 years old, 77% of them had visible signs of coronary atherosclerosis. This study showed that heart disease could affect people at a younger age and was not just a problem for older individuals. In 1992, a report showed that microscopic fatty streaks were found in the left anterior descending artery in over 50% of children aged 10–14, and 8% had even more advanced lesions with more accumulations of extracellular lipid. A 2005 report of a study from 1985 to 1995 found that around 87% of aortas and 30% of coronary arteries in the age group 5–14 years had fatty streaks, which increased with age.
Sources: en.wikipedia.org
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.
Reported human trials are few, brief and originate mainly from one country. They describe effects on anxiety-related measures, but sample sizes are small and reporting is limited. The results are widely regarded as preliminary rather than confirmed.
Reverse-phase liquid chromatography is used to assess purity and separation of related impurities. Mass spectrometry confirms that the observed molecular mass matches the expected peptide. A certificate of analysis from the supplier is the usual document of record.
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.