TP-7 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-08-28 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Primary route studied | Intranasal | Also examined parenterally in animal work |
| Reported plasma half-life | Minutes to tens of minutes | Values vary widely between reports |
| Main model systems | Rodent behavioural and cell assays | Human trials are few and small |
| Principal proposed targets | GABA-A receptor, GABA transaminase | Monoamine and neurotrophic pathways also reported |
| Evidence grade | Preliminary | Limited independent replication |
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.
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.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
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.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Recent economic growth has led to a considerable increase of new millionaires, including the new entrepreneurs, Colombians with a net worth exceeding US$1 billion. In 2017, however, the National Administrative Department of Statistics (DANE) reported that 26.9% of the population were living below the poverty line, of which 7.4% were in "extreme poverty". The multidimensional poverty rate stands at 17.0 percent of the population. The Government has also been developing a process of financial inclusion within the country's most vulnerable population. The contribution of tourism to GDP was US$5,880.3bn (2.0% of total GDP) in 2016. Tourism generated 556,135 jobs (2.5% of total employment) in 2016. Foreign tourist visits were predicted to have risen from 0.6 million in 2007 to 4 million in 2017.
==== Fengycins ==== Fengycins are another class of biosurfactant produced by Bacillus subtilis, with antifungal activity against filamentous fungi. There are two classes of Fengycins, Fengycin A and Fengycin B, with the two only differing by one amino acid at position 6 in the peptide sequence, with the former having an alanine residue, and the latter having valine.
== Incident and aftermath == RaDonda Vaught began work as a nurse at Vanderbilt University Medical Center in December 2015. On December 24, 2017, 75-year-old Charlene Murphey was admitted to the hospital for a subdural hematoma. Two days later, Vaught, a registered nurse, was instructed to administer Versed (midazolam, a sedating drug) to Murphey, but instead administered vecuronium (a paralyzing drug). Murphey was to be given Versed prior to an MRI scan. Vaught initially tried to withdraw Versed from an automated dispensing cabinet which was designed to communicate with the hospital's Medication Administration Record (MAR). Though an order for the intended medication (Versed) was present in Murphey's MAR, Vaught "couldn't find [it] in Murphey's profile" in the dispensing cabinet after typing "VE" into its search function without realizing she should have been looking for its generic name, midazolam. Vaught then triggered an override that unlocked a much larger swath of medications and then searched for "VE" again, and selected the first medication in the list (vecuronium). Vaught claimed that using overrides was a common and daily occurrence; other witnesses similarly testified that technical issues and delays at medication cabinets were common, and that "nurses could use overrides to overcome those delays." Vaught looked at the back of the vial and saw that it needed to be reconstituted, but did not look at the front of the vial to verify that it was, indeed, Versed. Vaught proceeded to reconstitute the vial, went to the imaging unit, and administered a dose to Murphey.
February 18: Law amending the Civil Code texts related to the legal capacity of married women. March 21: Order from the Ministry of Labor making binding the collective agreement for the wholesale wine and spirits trade in the Libourne district: within this agreement, wages differ notably based on the employee's gender (women receiving a "female wage," systematically lower than their male counterparts) — "this example of a collective agreement shows that the notion of 'female wage,' significantly lower than that of men, is embedded in the legal system of the time." April 9: Law regarding the promotion of female assistant inspectors in public welfare to the rank of inspector. November 12: Decree-law aimed at encouraging birth rates. 1939
=== Organ meats/offal === Lamb's liver, known as lamb's fry in New Zealand and Australia, is eaten in many countries. It is the most common form of offal eaten in the UK, traditionally used in the family favourite and pub grub staple of liver with onions, potentially also with bacon and mashed potatoes. It is a major ingredient, along with the lungs and heart (the pluck), in the traditional Scottish dish of haggis. Lamb testicles or lamb fries are a delicacy in many parts of the world. Lamb kidneys are found in many cuisines across Europe and the Middle East, often split into two halves and grilled (on kebabs in the Middle East), or sautéed in a sauce. They are generally the most highly regarded of all kidneys. Lamb sweetbreads are a delicacy in many cuisines.
Sources: en.wikipedia.org
== History == Carnitine was discovered in 1905 from muscle tissue, and it's chemical structure and properties were described in 1927. Carnitine's role as a vital metabolic compound was first hypothesized in 1952, when it was found to be essential to growth in mealworms. Mealworms with low carnitine "died fat", because they could not metabolize their stored fat when starved. Various studies in the 1950s showed that carnitine was acetylated by acyl-CoA and stimulated beta oxidation, which led researchers to the conclusion that carnitine transports fatty acids for metabolism.
=== Pharmacokinetics === Butane-1,4-diol is rapidly converted into GHB acid by the enzymes alcohol dehydrogenase and aldehyde dehydrogenase, and differing levels of these enzymes may account for differences in effects and side effects between users. While co-administration of ethanol and GHB already poses serious risks, co-administration of ethanol with 1,4-butanediol will interact considerably and has many other potential risks. This is because the same enzymes that are responsible for metabolizing alcohol also metabolize 1,4-butanediol so there is a strong chance of a dangerous drug interaction. Emergency room patients who overdose on both ethanol and 1,4-butanediol often present with symptoms of alcohol intoxication initially and as the ethanol is metabolized the 1,4-butanediol is then able to better compete for the enzyme and a second period of intoxication ensues as the 1,4-butanediol is converted into GHB.
Xanthoria parietina's extreme resilience has made it a focus of astrobiology and space-exposure research. Lichens are among the most stress-tolerant life forms, and X. parietina, with its strong UV defenses, has been tested for survivability in space and Mars-like conditions. Laboratory experiments simulating outer space conditions (high vacuum, cosmic UV radiation) exposed the lichen to 10–14 days of extreme stress. The lichen survived, remained metabolically active, and resumed growth after treatment, proving its short-term viability in space environments. Laboratory tests have further demonstrated the lichen's extraordinary cold tolerance, with dry samples surviving immersion in liquid nitrogen at temperatures below −182 °C (−295.6 °F). Building on these findings, X. parietina was tested under simulated Martian conditions in a 2023 study. Samples were exposed for 30 days to low pressure, a CO2-rich atmosphere, extreme temperature shifts, and high UV radiation. The lichen's health was monitored using chlorophyll fluorescence and structural analysis. It survived the full 30 days, retained photosynthetic ability, and maintained structural integrity, though UV-exposed samples showed reduced efficiency and some pigment degradation. Given this resilience, researchers suggested X. parietina as a candidate for long-term space exposure, such as on the International Space Station or satellites. A 2024 study further examined X. parietina's physiological resilience under simulated Martian conditions.
Grünwedel published the result of his explorations in 1912 in Altbuddhistische Kultstätten in Chinesisch Turkistan, Bericht über archäologische Arbeiten von 1906 bis 1907 bei Kuča, Qarašahr und in der Oase Turfan. Grünwedel discovered that the Kizil Caves were essential in the understanding of the development of Buddhist art, and suggested some forms of Western artistic influences as well:
The Bailey peptide synthesis is a name reaction in organic chemistry developed 1949 by J. L. Bailey. It is a method for the synthesis of a peptide from α-amino acid-N-carboxylic acid anhydrides (NCAs) and amino acids or peptide esters. The reaction is characterized by short reaction times and a high yield of the target peptide. The reaction can be carried out at low temperatures in organic solvents. The residues R1 and R2 can be organic groups or hydrogen atoms, R3 is the used amino acid or peptide ester: The reaction mechanism is not known in detail. Supposedly, the reaction begins with a nucleophilic attack of the amino group on the carbonyl carbon of the anhydride group of the N-carboxylic acid anhydride (1). After an intramolecular proton migration, a 1,4-proton shift and the cleavage of carbon dioxide follows, resulting in the peptide bond in the final product (2):
Sources: en.wikipedia.org
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.
The peptide enters plasma rapidly and is broken down by ordinary proteases into amino acids and shorter fragments. Reported half-lives are short. Whether meaningful amounts of the intact molecule reach the brain is an open question.
Most clinical reports are small, published in Russian and not independently replicated. English-language reviews highlight the absence of large randomised trials. Conclusions about efficacy should be treated as provisional.
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.