Tuftsin comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-05-18. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Proposed mechanisms centre on modulation of the GABAergic system, with reports of altered expression of genes related to GABA-A receptor subunits and changed monoamine turnover. Some studies describe inhibition of enkephalinase, the enzyme that degrades endogenous enkephalins, which may prolong opioid peptide signalling. Effects on brain-derived neurotrophic factor and on cytokine expression have also been reported. These findings come largely from animal models and small human studies, and the precise primary target remains unresolved.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Free peptide form |
| Molecular mass | About 751.9 Da | Calculated average mass |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form TKPRPGP |
| Structural basis | Tuftsin analogue | Extended version of a natural tetrapeptide |
| Development origin | Russian Academy of Sciences | Work carried out from the 1980s onward |
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.
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.
Expression vectors produce proteins through the transcription of the vector's insert followed by translation of the mRNA produced, they therefore require more components than the simpler transcription-only vectors. Expression in different host organism would require different elements, although they share similar requirements, for example a promoter for initiation of transcription, a ribosomal binding site for translation initiation, and termination signals.
== Technology development == The roots of liquid chromatography extend back over a century ago to 1900, when Russian botanist Mikhail Tsvet began experimenting with plant pigments in chlorophyll. He noted that, when a solvent was applied, distinct bands appeared that migrated at different rates along a stationary phase. For this new observation, he coined the term “chromatography,” a colored picture. His first lecture on the subject was presented in 1903, but his most important contribution occurred three years later, in 1906, when the paper “Adsorption analysis and chromatographic method. Applications on the chemistry of chlorophyll,” was published. Rivalry with a colleague who readily and vocally denounced his work meant that chromatographic analysis was shelved for almost 25 years. The great irony of the matter is that it was his rival's students who later took up the chromatography banner in their work with carotins. Greatly unchanged from Tswett's time until the 1940s, normal phase chromatography was performed by passing a gravity-fed solvent through small glass tubes packed with pellicular adsorbent beads. It was in the 1940s, however, that there was a great revolution in gas chromatography (GC). Although GC was a wonderful technique for analyzing inorganic compounds, less than 20% of organic molecules are able to be separated using this technique. It was Richard Synge, who in 1952 won the Nobel Prize in Chemistry for his work with partition chromatography, who applied the theoretical knowledge gained from his work in GC to LC.
49 Squadron RAF in October 1956 in Operation Buffalo at Maralinga; Project Dazzle and its research on re-entry vehicles enabled the Mercury-Atlas 6 launch to happen in February 1962; the Australian government built four launch pads for the Blue Streak in 1959, but it was cancelled in 1960, the redesignated satellite launcher Blue Streak first launched on 5 June 1964, and satellites would be launched by 1966, but only WRESAT was launched in November 1967, on a Redstone rocket instead; Woomera launched over 4000 missiles and cost the Australian government £900m; the site was demolished by the Australian government at the end of the 1960s; part of the former site is now the secret Joint Defense Facility Nurrungar 17 September Not in the Stars, making mathematical models for predictions; Robert May, Baron May of Oxford of Imperial College; William Phillips and his 1949 MONIAC economic model; a British Airways 747 flight simulator; computer models of epidemics - the R number, and vaccination policies; the UK fishing industry had quotas imposed in 1983, due to mathematical models of fish stocks; John Shepherd of the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) laboratory in Lowestoft; computer models of warfare were developed by the Defence Operational Analysis Establishment in West Byfleet with deputy director David Faddy, which closed six years later, superseded in function by CORDA (UK); Irving Mintzer of the World Resources Institute; the NASA Goddard Space Flight Center had developed computer models of the Earth's atmosphere, such as rainfall; the hole in the Ozone layer and phytoplankton, with Norman Myers; Ian Riley of the Economist Intelligence Unit. Narrated by Bob Peck. Written, produced and directed by Chris Haws, made by InCA 24 September Race for the Top, CERN versus Fermilab; in 1983 CERN discovered the W and Z bosons, it and Fermilab were looking for the top quark; Leon M. Lederman, director of Fermilab; Andy Parker of CERN; CERN had 80 scientists led by Luigi Di Lella on its UA2 experiment, and Fermilab had its Collider Detector at Fermilab (CDF); Roy Schwitters; Fermilab had discovered the bottom quark in 1977; John Ellis of CERN; each team prepared for an annual physics conference at La Thuile, Aosta Valley in north-west Italy; UA2 had a meeting in July 1989 in Cambridge; the top quark would be discovered in 1995 with 175 GeV by Fermilab. Narrated by Carole Boyd, known for playing Lynda Snell in The Archers, joint production InCA and WGBH 1 October Walk on Wheels, a half-million disabled people have a wheelchair in the UK; NHS wheelchairs were made by Carter's; the quick-release axle was developed in World War II, for releasing munitions; the residential Treloar School in Alton, Hampshire, which was funded by individual LEAs, with charity funding as well; Bill Walmsley of the Department of Health's wheelchair research centre in Blackpool, now part of the Disability and Carers Service at DWP Peel Park at the end of the M55 motorway, on the A5230 in Westby-with-Plumptons. Narrated by John Hedges, produced by Jeremy Llewellyn-Jones, made by Chrysalis Television (North One Television) 8 October Invasion of the Body Scanners, a reference to the 1956 film Invasion of the Body Snatchers; X-rays were introduced in the 1890s, but it took fifty years to vastly improve the early crude techniques; CT was invented in the late 1960s - its inventor with Prince Philip, Duke of Edinburgh; Ian McDougall at a magnet technology company, who designed the first magnet, cooled with liquid helium in 1979; X-ray scans were a fairly crude process, but other types required computer image processing; Michael Boswell of GE Medical Systems; scans were taken in the coronal plane and sagittal plane; by 1989 the NHS only had four of these scanners - one was at Frenchay Hospital, made by GEC Medical (Picker International) - there were around 25 scanners in the whole UK; the Brockton Hospital; there were 1500 scanners in the US, with 39 in Massachusetts; Donald Longmore of the National Heart and Chest Hospitals, who performed the UK's first heart transplant on 3 May 1968; CT scanning had been performed for neuroradiology since the mid-1970s; radiology at Middlesex Hospital; medical ultrasound was a much safer technique than X-rays, and a new type deployed the Doppler effect, but medical ultrasound lacked cast-iron image definition; but scanners were hideously expensive, due to the convoluted enormous magnets that were required. Narrated by John Benson, produced by Mike Johnstone, directed by Ed Newstead, made by VATV (Video Arts) 15 October Wheels of War, about the early 1990s Leyland 4-tonne truck and defence procurement; James Adams, journalist; military historian Correlli Barnett; general service (GS) cargo vehicles, and a RE vehicle carrying a Medium Girder Bridge; a youthful-looking Mark Francois; the Austin Champ, designed in the 1950s; the British Aerospace Nimrod AEW3 was cancelled in 1986 at a cost of £860m; cost-plus contracts were replaced by competitive; Sir Peter Levine was brought in as Chief of Defence Procurement; the Leyland 4-tonne truck would replace the Bedford MK, made by Bedford Vehicles; journalist John Parsons; each vehicle would cost around £23,000 each; the Leyland 5-tonne was developed from its Comet and Roadrunner vehicles (developed into the DAF LF) under project director Stuart Hayes; the equivalent German vehicle, the MAN KAT1, had cost £75,000 each; the Panavia Tornado; Leyland design engineer Colin Ingram; the three vehicle prototypes were punishingly tested at the Royal Armament Research and Development Establishment (RARDE). Narrated by Anthony Valentine, produced by Patrick Uden made by Uden Associates 22 October Three Score Years and Then? 29 October Robotopia, advances of robotics in Japan, and bizarre contraptions; Frederik L. Schodt, author of the 1988 book Inside the Robot Kingdom - for hundreds of years until 1853, Japan was a fairly backward country; Joseph Engelberger, who developed the first industrial robot, Unimate, made by his company Unimation from 1961 - there were around 200,000 industrial robots, with around 130,000 of those in Japan; Japanese robot artist Hajime Sorayama, who drew lurid female robots; automated mannequins; nineteen universities in Japan were developing ungainly humanoid robots, notably Ichiro Kato at Waseda University; Seiuemon Inaba of FANUC, produced by Mike Wallington, made by Kai Productions 5 November Fly-by-wire, the new Airbus 320; software engineer Mike Hennell of the University of Liverpool; Roger Beteille, managing director of Airbus from 1967–85, and Henri Ziegler; John Knight of the University of Virginia; software engineer Bev Littlewood of City University; the A320 was the first fly-by-wire airliner; Blind Landing Experimental Unit testing at RAE Bedford in the 1960s, and developing the automatic pilot with a Vickers Valetta; testing Concorde in a wind tunnel; the Apollo project had depended on computers - it couldn't be done otherwise; Paul Ceruzzi of the Air and Space Museum; Philip Felleman of the Draper Laboratory; testing the F-16 in the early 1970s; Joe Sutter, head of Boeing from 1981–86; Boeing introduced flight management systems, so not needing a flight engineer; David Learmount of Flight International, and how Airbus had more commercial need to be innovative; the A300 was the first two-engined wide body aircraft; the A310 had electrical hydraulics and electronic control of some flight surfaces; John Cullyer of the University of Warwick; the A320 had five master computers; Gordon Corps, the Airbus test pilot, later to fly on Thai Airways International Flight 311 in 1992; Gilles Pichon, chief engineer of the A320; Jacques Troyes, head of Flight Control at Airbus; there was emergency mechanical control to the rudder and tail trim; the June 1988 Air France Flight 296Q - Michel Asseline, the pilot, said the aircraft had tried to land, when he tried to raise the aircraft; Alain Monnier of the DGAC said it was pilot error; Greg Holt of the FAA and Brian Perry of the CAA; the four-engined A330 would be manufactured from 1992; a prototype fly-by-wire relaxed stability Saab JAS 39 Gripen tumbles on 2 February 1989 at Linköping/Saab Airport, piloted by Lars Rådeström. Narrated by James Bellini, produced by Ben Shephard (historian), directed by John Longley, made by Box Television with WGBH 12 November Deadly Force, aerial shots of Miami; the WINZ Miami broadcaster; the Miami SWAT response team; the 1980 Miami riots; Sgt Louis Battle, Bernie Gonzalez and the Heckler & Koch MP5; Tom Salerno and the Remington Model 870 pump action shotgun, the M1911 pistol and Beretta M9; Ted Bradley; a WSVN news broadcast with Jane Akre; two thirds of Miami's population were Latin-American, and had many exiled citizens; the 1980 Mariel boatlift, from Cuba, added to the population and much to the crime; Miami had two murders a day in the 1980s; Robert Waller; Edna Buchanan of the Miami Herald; severed limbs washed up on Miami beach; the Colt Python; the Beretta 92; the Colt AR-15 semi-automatic rifle; 80% of SWAT call-outs were connected to the drug trade; two thirds of illegal drugs went through Miami; Sgt Louis Philips and negotiation techniques; SWAT negotiator Eric Caspener; 95% of SWAT negotiations work. Produced by David Jones, directed by Catherine Bailey, made by Buffalo Pictures 19 November Faster than a Speeding Bullet, and the quest for supersonic flight, eventually resulting in Concorde. The programme features former Concorde pilot Christopher Orlebar, who wrote The Concorde Story. The history of supersonic research dates back to the 18th Century, but supersonic flight only became achievable after the development of the jet engine. Featured aircraft include: the wartime Messerschmitt Me 262; the innovative de Havilland DH 108; the Messerschmitt Me 163 Komet; the Fairey Delta 2, the Bell X1 and numerous experimental "X Planes". After the war, the world's fastest non-experimental aircraft was the Lockheed SR-71 Blackbird, which could fly at 95,000 ft at 2,300 mph. The programme interviews key figures in the development of supersonic military aircraft and second generation SST (Supersonic Transport) aircraft. Narrated by Tony Anholt, written, produced and directed by Chris Haws, made by InCA
Sources: en.wikipedia.org
== Phytochemicals == Polyphenol research on maqui berries showed anthocyanin content to include eight glucoside pigments of delphinidin and cyanidin, with the principal anthocyanin being delphinidin 3-sambubioside-5-glucoside (34% of total anthocyanins). The average total anthocyanin content was 138 milligrams (2.13 gr) per 100 grams (3.5 oz) of fresh fruit, or 212 milligrams (3.27 gr) per 100 grams (3.5 oz) of dry fruit, ranking maqui berries low among darkly pigmented fruits for anthocyanin content (see table at anthocyanins). One study found that anthocyanins are also present in maqui leaves. Other phytochemicals extracted from the leaves were the alkaloids aristoteline, aristoquinoline, and aristone.
== Odor characteristics == The odour of the mixed isomers is perceived as "fatty, green, waxy, cucumber, melon". The odour of the (Z)-isomer is "orris, fatty, waxy, cucumber" whilst that of the (E)-isomer is "fatty, green, cucumber, aldehydic". Its odor has been associated with human body odor alterations during aging.
== In fiction == Excretion was traditionally a taboo subject in fiction and was rarely depicted explicitly, although later works have used it for satire, worldbuilding, horror and speculation about technology. The Encyclopedia of Science Fiction notes examples ranging from the reversed social taboos surrounding defecation in Brian Aldiss's The Dark Light Years (1964) to waste-recycling technologies in works such as Frank Herbert's Dune (1965), while spaceflight fiction has sometimes addressed the practical problems of sanitation and waste disposal. Depictions can also serve social or political purposes: Ursula K. Le Guin's "The Ones Who Walk Away from Omelas" (1973) associates excrement with the degradation of the abused child on whom its utopian society depends, while later works have employed toilets and excretion for comedy, horror and speculative depictions of future technology.
Sources: en.wikipedia.org
It is a seven-amino-acid peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, produced by chemical synthesis rather than extracted from biological tissue. Its design is based on tuftsin, a natural immunomodulatory tetrapeptide. The C-terminal Pro-Gly-Pro segment is a common stabilising motif in short regulatory peptides.
The core four residues correspond to tuftsin, which occurs naturally as part of immunoglobulin G. The full seven-residue sequence, however, is not a known endogenous peptide. It is a laboratory-designed analogue intended to combine tuftsin-like activity with greater resistance to breakdown.
No single receptor has been confirmed as the primary target. Reports describe involvement of the GABAergic system, interference with enkephalin degradation, and shifts in neurotrophic factor expression. Because these observations come from different models and assays, they have not yet been integrated into one accepted mechanism.
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.