This is a working overview of Pro-Gly-Pro, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-26 and is reviewed periodically as new material appears.
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.
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.
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.
| 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 |
Tuftsin, the parent structure, is a naturally occurring immunomodulatory tetrapeptide released from the Fc region of immunoglobulin G by spleen enzymes. Selank extends this four-residue sequence with three additional amino acids. The stated rationale is that the added tail slows enzymatic breakdown and may influence receptor interactions. How the full heptapeptide behaves at the molecular level is not firmly established, and proposed mechanisms often involve indirect modulation of neurotransmitter or immune signaling rather than a single defined target.
Selank is a synthetic heptapeptide developed in Russia. Its sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, a seven-residue chain built around the natural tetrapeptide tuftsin. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences first described the compound in the mid-1990s. The design combined the tuftsin core with an added Pro-Gly-Pro tail, a modification intended to extend the molecule's stability in biological fluids. Published work on the peptide has appeared mainly in Russian-language journals.
Reported activity for Selank centers on anxiolytic and nootropic effects. Russian clinical reports describe use in anxiety and in cognitive or attention-related complaints. Most of this evidence comes from studies conducted by the same research groups that developed the peptide. Independent replication in other countries remains limited, and no major Western regulatory agency has approved the compound for any indication. The gap between local reports and external verification is a recurring point in discussions of the peptide.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
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.
Gene expression in mammals is regulated by many cis-regulatory elements, including core promoters and promoter-proximal elements that are located near the transcription start sites of genes, upstream on the DNA (towards the 5' region of the sense strand). Other important cis-regulatory modules are localized in DNA regions that are distant from the transcription start sites. These include enhancers, silencers, insulators and tethering elements. Enhancers and their associated transcription factors have a leading role in the regulation of gene expression. Enhancers are genome regions that regulate genes. Enhancers control cell-type-specific gene expression programs, most often by looping through long distances to come in physical proximity with the promoters of their target genes. Multiple enhancers, each often tens or hundred of thousands of nucleotides distant from their target genes, loop to their target gene promoters and coordinate with each other to control gene expression. The illustration shows an enhancer looping around to come into proximity with the promoter of a target gene. The loop is stabilized by a dimer of a connector protein (e.g. dimer of CTCF or YY1). One member of the dimer is anchored to its binding motif on the enhancer and the other member is anchored to its binding motif on the promoter (represented by the red zigzags in the illustration). Several cell function-specific transcription factors (among the about 1,600 transcription factors in a human cell) generally bind to specific motifs on an enhancer.
In 2020, incumbent Republican President Donald Trump sought re-election but was defeated by Democratic challenger Joe Biden. Democratic U.S. Senator Kamala Harris of California was elected vice president in 2020 as Biden's running mate. Trump is the first president in American history to be impeached twice and run for president again after impeachment. As Trump was acquitted by the Senate in both cases, he was not barred from seeking reelection to the presidency in 2024.
Consolidate the rule of the CCP Ensure sovereignty, territorial integrity, internal security and national development of the People's Republic of China Safeguard the country's interests Help maintain world peace China describes its military posture as active defense, defined in a 2015 state white paper as "We will not attack unless we are attacked, but we will surely counterattack if attacked."
Electrostatic interaction: In an aqueous environment, the oppositely charged groups in amino acid side chains within the active site and substrates attract each other, which is termed electrostatic interaction. For example, when a carboxylic acid (R-COOH) dissociates into RCOO− and H+ ions, COO− will attract positively charged groups such as protonated guanidine side chain of arginine. Hydrogen bond: A hydrogen bond is a specific type of dipole-dipole interaction between a partially positive hydrogen atom and a partially negative electron donor that contain a pair of electrons such as oxygen, fluorine and nitrogen. The strength of hydrogen bond depends on the chemical nature and geometric arrangement of each group. Van der Waals force: Van der Waals force is formed between oppositely charged groups due to transient uneven electron distribution in each group. If all electrons are concentrated at one pole of the group this end will be negative, while the other end will be positive. Although the individual force is weak, as the total number of interactions between the active site and substrate is massive the sum of them will be significant. Hydrophobic interaction: Non-polar hydrophobic groups tend to aggregate together in the aqueous environment and try to leave from polar solvent. These hydrophobic groups usually have long carbon chain and do not react with water molecules. When dissolving in water a protein molecule will curl up into a ball-like shape, leaving hydrophilic groups in outside while hydrophobic groups are deeply buried within the centre.
Sources: en.wikipedia.org
into the general solution produces orbits that escape to infinity (while still satisfying the equation of motion). Substituting the definitions for the axial and cyclotron frequencies, one might also write this condition as
ERP (Enterprise Resource Planning): Delivering full-lifecycle services from consulting and deployment to operations and optimization, the company promotes its 'AX on ERP' strategy, embedding Agentic AI to automate corporate business processes. It continues to strengthen its strategic partnership with SAP, showcasing its ERP capabilities annually at 'SAP Sapphire' since 2024. In 2025, LG CNS became the first South Korean company to join SAP’s Regional Strategic Services Partner (RSSP) initiative for the Asia-Pacific region. PerfecTwin: A test automation system based on live transaction data validation technology. By accurately replicating live business context within simulated environments, it verifies systems before deployment to ensure transaction quality and stability. LG Optapex: A global marketing technology platform driven by artificial intelligence (AI) and mathematical optimization algorithms. Tailored for the Amazon e-commerce ecosystem, it automates advertising operations, including 24/7 automated bidding, budget allocation, and performance forecasting. By integrating product-level data such as profit margins, fees, shipping costs, and inventory levels, the platform maximizes seller profitability in real time. AX (AI Transformation): LG CNS delivers enterprise-grade services driven by generative AI and Agentic AI. The company applies AI technologies across diverse industry sectors, including manufacturing, finance, public services, defense, and pharmaceuticals. It operates its proprietary platform, 'AgenticWorks', to assist enterprises in adopting AI agents.
India remained a member of the Commonwealth of Nations after becoming a republic in 1950. It strongly supported decolonisation in Africa and Asia in the 1950s, and played a leading role in the Non-Aligned Movement. Following a period of cordial relations in the 1950s, India and China went to war in 1962, resulting in a decisive military defeat for India. By 1967, however, India was able to fend off Chinese excursions into Sikkim. India has had uneasy relations with its western neighbour, Pakistan. The two went to war in 1947, 1965, 1971, and 1999. Three wars were fought over the disputed territory of Kashmir. After the 1965 war, India began to pursue close military and economic ties with the Soviet Union. By the late 1960s, the Soviet Union was India's largest arms supplier. China's nuclear test of 1964 and threats to intervene in support of Pakistan in the 1965 war caused India to produce nuclear weapons. India conducted its first nuclear weapons test in 1974 and carried out additional underground testing in 1998. India has signed neither the Comprehensive Nuclear-Test-Ban Treaty nor the Nuclear Non-Proliferation Treaty, calling both flawed and discriminatory. India maintains a "no first use" nuclear policy and possesses a nuclear triad as a part of its "Minimum Credible Deterrence" doctrine. Since the end of the Cold War, India has increased its economic, strategic, and military cooperation with the United States and the European Union. In 2008, a civilian nuclear agreement was signed between India and the United States.
== Honors and awards == Independent Scientist Research (K02) Award, National Institute of Mental Health, 2002–2007. Fellow, Association for Psychological Science, 2003. Fellow, Society for Personality and Social Psychology, 2005. Fellow, American Psychological Association, 2005. Career Trajectory Award, Society of Experimental Social Psychology, 2006. Cattell Fund Fellowship, 2007–2008. NIH Director's Pioneer Award, 2007–2012, to study how the brain creates emotion. Kavli Fellow, National Academy of Sciences, 2008. Elected Fellow, American Association for the Advancement of Science, 2008. Arts in Academics award, University of Waterloo, 2010. Excellence in Research and Creative Activity Award, Northeastern University, 2012. Elected Fellow, Royal Society of Canada, 2012. Award for Distinguished Service in Psychological Science, American Psychological Association, 2013. Elected Fellow, Society of Experimental Psychologists, 2013. Diener Award in Social Psychology, Society for Personality and Social Psychology, 2014. Heritage Wall of Fame, Foundation for Personality and Social Psychology, 2016. Mentor Award for Lifetime Achievement, Association for Psychological Science, 2018. Elected Fellow, American Academy of Arts and Sciences, 2018. President, Association for Psychological Science, 2019–2020. Guggenheim Fellowship in neuroscience, 2019. John P. McGovern Award in the Behavioral Sciences, American Association for the Advancement of Science, 2020. APA Award for Distinguished Scientific Contributions, American Psychological Association, 2021.
== External links == A Free Android application for molecular and reciprocal weight calculation of any chemical formula Stoichiometry Add-In for Microsoft Excel Archived 2011-05-11 at the Wayback Machine for calculation of molecular weights, reaction coefficients and stoichiometry.
Sources: en.wikipedia.org
In 1894, Hungarian inventor and industrialist István Röck started to manufacture a large industrial ammonia refrigerator which was powered by electric compressors (together with the Esslingen Machine Works). Its electric compressors were manufactured by the Ganz Works. At the 1896 Millennium Exhibition, Röck and the Esslingen Machine Works presented a 6-tonne capacity artificial ice producing plant. In 1906, the first large Hungarian cold store (with a capacity of 3,000 tonnes, the largest in Europe) opened in Tóth Kálmán Street, Budapest, the machine was manufactured by the Ganz Works. Until nationalisation after the Second World War, large-scale industrial refrigerator production in Hungary was in the hands of Röck and Ganz Works. Commercial refrigerator and freezer units, which go by many other names, were in use for almost 40 years prior to the common home models. They used gas systems such as ammonia (R-717) or sulfur dioxide (R-764), which occasionally leaked, making them unsafe for home use. Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic, non-flammable synthetic refrigerants such as Freon-12 (R-12) were introduced. However, R-12 proved to be damaging to the ozone layer, causing governments to issue a ban on its use in new refrigerators and air-conditioning systems in 1994. The less harmful replacement for R-12, R-134a (tetrafluoroethane), has been in common use since 1990, but R-12 is still found in many old systems.
=== Spray drying === King later turned to spray drying of beverages and other liquids, for which the loss of volatile flavor and aroma substances occurs largely in the spray-nozzle zone, where the droplets to be dried are formed. King and his colleagues examined factors influencing the loss of volatile flavors and aroma and also the factors affecting the development of particle morphology (size, shape, porosity, and thus the bulk density) of the dried product. They interpreted the factors that cause spray-dried particles to be sticky. In later research, King and his colleagues created a device to enable simultaneous measurement of particle morphology and loss of volatile components as the drying of single drops to particles took place. This research was supported by the National Science Foundation. He prepared review articles on retention of volatile flavor and aroma components during spray drying. In later research, King and his colleagues created a device to enable simultaneous measurement of particle morphology and loss of volatile components as the drying of single drops to particles took place.
During World War II, Seymour Cobley of the Brittish Royal Horticultural Society donated 83,000 tulips to Canada from 1941 to 1943 to honour Canadian involvement in the war. The Canadian Tulip Festival (French: Festival Canadien des Tulipes; Dutch: Canadees Festival van de Tulp) is a tulip festival held annually each May in Ottawa, Ontario, Canada. The festival claims to be the world's largest tulip festival, displaying over one million tulips, with attendance of over 650,000 visitors annually. The festival is a cultural and historical aspect of the special Canada–Netherlands relationship, having originated with commemorative donations of tulips to Canada from the Netherlands for Canadian actions during World War II, when Canadian forces led the liberation of the Netherlands and hosted the Dutch royal family in exile.
The detection of a surge in release of luteinizing hormone indicates impending ovulation. LH can be detected by urinary ovulation predictor kits (OPK, also LH-kit) that are performed, typically daily, around the time ovulation may be expected. A conversion from a negative to a positive reading would suggest that ovulation is about to occur within 24–48 hours, giving women two days to engage in sexual intercourse or artificial insemination with the intention of conceiving. The recommended testing frequency differs between manufacturers. For example, the Clearblue test is taken daily, and an increased frequency does not decrease the risk of missing an LH surge. On the other hand, the Chinese company Nantong Egens Biotechnology recommends using their test twice per day. If testing once per day, no significant difference has been found between testing LH in the morning versus in the evening, in relation to conception rates, and recommendations of what time in the day to take the test varies between manufacturers and healthcare workers. Tests may be read manually using a color-change paper strip, or digitally with the assistance of reading electronics. Tests for luteinizing hormone may be combined with testing for estradiol in tests such as the Clearblue fertility monitor. The sensitivity of LH tests are measured in milli international unit, with tests commonly available in the range 10–40 m.i.u. (the lower the number, the higher the sensitivity).
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.
Purity is usually reported as an HPLC area percentage, most often measured at 214 nm. Identity is confirmed separately by mass spectrometry. A certificate of analysis should state both the method and the observed value.