A practical reference on TP-7: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-09-03 and is reviewed periodically as new material appears.
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 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.
Measuring peptide exposure inside the brain is technically difficult. Selank is degraded rapidly in plasma, and assays must separate intact peptide from fragments, which favors targeted mass spectrometry over immunoassays alone. Reported half-lives are short, on the order of minutes, so effects observed hours later are attributed to downstream signaling rather than to the parent compound. Blood-brain barrier permeability is debated and rarely quantified directly. Gaps include absent dose-response characterization, inconsistent reporting of purity, and almost no pharmacokinetic data from human participants.
Selank is studied chiefly as an animal-model anxiolytic with proposed secondary effects on memory and immune signaling. Reported mechanisms include modulation of the GABA-A receptor complex, inhibition of enkephalin-degrading enzymes, and shifts in monoamine turnover within limbic structures. Some experiments describe increased expression of brain-derived neurotrophic factor in the hippocampus after repeated dosing. No single molecular target has been confirmed, and the peptide does not bind any receptor with the selectivity typical of a conventional small-molecule drug. Mechanism therefore remains a set of hypotheses rather than an established pathway.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analog of the tetrapeptide tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Reported consistently across pharmacopoeial descriptions |
| Appearance | White to off-white lyophilized powder | Typical form of research-grade material |
| Solubility | Freely soluble in water | Aqueous buffers; poor in nonpolar solvents |
| Typical storage temperature | -20 degrees Celsius | Lyophilized powder; protect from moisture |
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter notation. Its structure consists of the immunomodulatory tetrapeptide tuftsin, Thr-Lys-Pro-Arg, extended at the carboxyl terminus by a Pro-Gly-Pro segment. The molecular formula is commonly given as C33H57N11O9, corresponding to a monoisotopic mass near 751.4 Da and an average molecular mass near 751.9 Da. All seven residues are proteinogenic amino acids, and the molecule carries no modified side chains or non-natural linkages.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
== Discovery == Humanin was the first mitochondria-derived peptide to be discovered. Humanin was independently found by three different labs looking at different parameters. The first to publish, in 2001, was the Nishimoto lab, which found humanin while looking for possible proteins that could protect cells from amyloid beta, a major component of Alzheimer's disease. The Reed lab found humanin when screening for proteins that could interact with Bcl-2-associated X protein (Bax), a major protein involved in apoptosis. The Pinchas Cohen lab independently discovered humanin when screening for proteins that interact with IGFBP3.
=== Illegal gambling groups === Jogo do bicho (Animal game) is an illegal gambling game in Brazil, which is still incredibly popular and sought out despite its federal prohibition in 1946. The game is played all around the country, with lottery-style drawings in every state occurring daily in its headquarters in Greater Rio de Janeiro. The game is controlled by bosses, called bicheiros or banqueiros ("bankers"). Jogo do Bicho is a longstanding staple in Brazilian culture, with thousands participating in the game daily. Because of its potential to circulate and raise large sums of money, control of Jogo do Bicho is lucrative and largely contributes to corruption, with politicians, judicial personnel, and members of the police force all monetarily and politically benefitting from it. Bicheiros also contribute funding to social programs, such as samba schools, which play a critical role in cultural festivities such as Brazilian Carnival. Because of this, Jogo do Bicho, and in turn its bicheiros, are deeply ingrained in Brazilian culture, especially in Rio de Janeiro, and contribute to the landscape of organized crime and corruption.
In 2002, they developed an unnatural base pair between 2-amino-8-(2-thienyl)purine (s) and pyridine-2-one (y) that functions in vitro in transcription and translation, for the site-specific incorporation of non-standard amino acids into proteins. In 2006, they created 7-(2-thienyl)imidazo[4,5-b]pyridine (Ds) and pyrrole-2-carbaldehyde (Pa) as a third base pair for replication and transcription. Afterward, Ds and 4-[3-(6-aminohexanamido)-1-propynyl]-2-nitropyrrole (Px) was discovered as a high fidelity pair in PCR amplification. In 2013, they applied the Ds-Px pair to DNA aptamer generation by in vitro selection (SELEX) and demonstrated the genetic alphabet expansion significantly augment DNA aptamer affinities to target proteins.
Isotonitazene is a synthetic opioid analgesic drug from the nitazene class and structural homolog of etonitazene, which has been sold as a designer drug. It has only around half the potency of etonitazene in animal studies, but it is likely even less potent in humans as was seen with etonitazene (1000 times as potent as morphine in animal models yet only 60 times as potent in humans). Isotonitazene (obtained from an online vendor) was fully characterized in November 2019 in a paper where the authors performed a full analytical structure elucidation in addition to determination of the potency at the μ-opioid receptor using a biological functional assay in vitro. While isotonitazene was not compared directly to morphine in this assay, it was found to be around 2.5 times more potent than hydromorphone and slightly more potent than fentanyl.
RNAi Atlas: a database of RNAi libraries and their target analysis results miRSearch Archived 2012-12-04 at the Wayback Machine: Tool for finding microRNAs that target mRNA How mRNA is coded?: YouTube video What is mRNA?: theconversation.com
Sources: en.wikipedia.org
Coronary occlusion is caused by the buildup of fats, cholesterol and other substances in and on the walls of the hearts arteries. As plaque builds up, the arteries narrow. Plaque often starts building up during childhood and is heavily influenced by genetics, but also lifestyle and high blood cholesterol. This condition is referred to as atherosclerosis. The buildup on the walls of the hearts arteries is referred to as plaque. Plaque causes arteries to narrow and block blood flow. Conditions that aid in the development of coronary artery disease are diabetes or insulin resistance, high blood pressure, sedentary lifestyle, and smoking or tobacco use. Risk Factors that are not controllable are age, birth sex, and family history. Getting older increases the risk of damaged and narrowed arteries. Men are at a greater risk of coronary artery disease, with women's risk increasing after menopause.
Berylliosis, or chronic beryllium disease (CBD), is a chronic allergic-type lung response and chronic lung disease caused by exposure to beryllium and its compounds, a form of beryllium poisoning. It is distinct from acute beryllium poisoning, which became rare following occupational exposure limits established around 1950. Berylliosis is an occupational lung disease. While there is no cure, symptoms can be treated.
=== March === 4 March – Banco Master scandal: The Supreme Federal Court orders the arrest of former Banco Master president and major shareholder Daniel Vorcaro in a potential fraud case worth up to 12 billion reais. The Federal Senate ratifies the EU–Mercosur Partnership Agreement. 5 March – A nursing home collapses in Belo Horizonte, killing eight people and leaving four missing. 10 March – Ski racer Cristian Ribera becomes the first athlete representing Brazil to win a medal in the Paralympics after achieving silver in the para-cross-country skiing men's seated sprint at the 2026 Winter Paralympics in Italy. 14 March – President Lula revokes the visa of US diplomat Darren Beattie after the latter tries to visit former president Jair Bolsonaro in prison. Three Israeli nationals are arrested after clashing with pro-Palestine demonstrators in Itacare. 17 March – A law restricting access to social media by minors comes into effect. 18 March – Eight people, including Comando Vermelho commander Claudio Augusto dos Santos, are killed in police raids across Rio de Janeiro. 20 March – Fernando Haddad resigns as finance minister after announcing that he would run for governor of Sao Paulo.
== Evolutionary origins == The lungs of today's terrestrial vertebrates and the gas bladders of today's fish are believed to have evolved from simple sacs, as outpocketings of the oesophagus, that allowed early fish to gulp air under oxygen-poor conditions. These outpocketings first arose in the bony fish. In most of the ray-finned fish, the sacs evolved into closed off gas bladders, while a number of carp, trout, herring, catfish, and eels have retained the physostome condition with the sac being open to the oesophagus. In more basal bony fish, such as the gar, bichir, bowfin and the lobe-finned fish, the sacs have evolved to primarily function as lungs. The lobe-finned fish gave rise to the land-based tetrapods. Thus, the lungs of vertebrates are homologous to the gas bladders of fish (but not to their gills).
Sources: en.wikipedia.org
=== GGQ motif === The GGQ motif is a conserved amino acid sequence in release factors through all domains of life. The GGQ site consists of two glycine amino acids followed by a glutamine. In eRF1, the GGQ site is on residues 183-185 of the polypeptide, which is located on Domain 2. The distant orientation of the GGQ site is stabilized by the hydrophobic effects of neighboring amino acid residues such as leucine 176, proline 177, phenylalanine 190, and leucine 193. The gln185 residue of the GGC motif is thought to be the main catalytic site for the hydrolysis of the peptidyl-tRNA ester bond in the peptidyl transferase of the ribosome. The GGQ site is not associated with any functions of stop codon recognition, ribosomal docking, or eRF3 binding.
It is a hard technique, which tends to break down large molecule ions during flight, since large molecules are particularly easy to fragment. Furthermore, large molecules are hard to volatilize without being degraded by heat.
By at least 1731, it was officially codified in Naval regulation that each sailor was rationed one pound (450 g) of biscuit per day. Hardtack was also utilized by the Pilgrims during their 1620 voyage, primarily due to its easy storage and long lifespan. However, the travelers struggled with insect infestation, as well as having to dip the hardtack into water for it to be edible. Hardtack, crumbled or pounded fine and used as a thickener, was a key ingredient in New England seafood chowders from the late 1700s. In 1801, Josiah Bent began a baking operation in Milton, Massachusetts, selling "water crackers" made of flour and water that would be resistant to deterioration during long sea voyages from the port of Boston. These were also used extensively as a source of food by the gold prospectors who migrated to the gold mines of California in 1849. Since the journey took months, hardtack was stored in the wagon trains. Bent's company later sold the original hardtack crackers used by troops during the American Civil War. The G. H. Bent Company operated in Milton and sold these items to Civil War re-enactors and others until 2018.
Sources: en.wikipedia.org
Selank is a synthetic seven-amino-acid peptide modeled on tuftsin, a fragment of the immunoglobulin G heavy chain. It was designed in Russia to combine anxiolytic and immunomodulatory properties in one molecule.
The first four residues of Selank reproduce the tuftsin sequence Thr-Lys-Pro-Arg. A Pro-Gly-Pro extension at the C-terminus was added to slow enzymatic breakdown and extend residence time.
It holds marketing authorization in Russia, where nasal drop formulations are sold. No equivalent approval exists in the European Union, the United States, or most other countries.
Intranasal administration predominates in both animal and human research because it avoids hepatic first-pass metabolism. Injectable and intraperitoneal routes appear in animal work mainly for comparison.