The short version of nootropic fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-03-25 and is reviewed periodically as new material appears.
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.
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 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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Modeled on tuftsin |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Seven residues |
| Approximate molecular mass | Around 750 Da | Depends on counter-ion and hydration |
| Common forms | Lyophilized powder | Also described as aqueous solution |
| Primary origin of research | Russian laboratories | Mid-1990s onward |
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.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
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.
Selank is not a naturally occurring peptide and has no known endogenous counterpart in human physiology. Russian-language sources frequently call it TP-7, while English-language sources use the name Selank almost exclusively. Database indexing is uneven, partly because early reports appeared in regional journals that are not widely cataloged. Some summaries describe the material as a tuftsin analog and others as a synthetic heptapeptide; the labels overlap rather than conflict. Citing the primary sequence resolves ambiguity more reliably than the research or trade name alone.
Pyrimidine oxygenase (EC 1.14.99.46, gene RutA) is an enzyme characterised from Escherichia coli with systematic name uracil,FMNH2:oxygen oxidoreductase (uracil hydroxylating, ring-opening). It catalyses two related oxidation reactions which act on pyrimidine nucleobases. The overall effect of the first example is to convert uracil to (Z)-3-ureidoacrylic acid with molecular oxygen as the oxidant and flavin mononucleotide (FMN) as a cofactor. The enzyme also requires nicotinamide adenine dinucleotide (NADH):
In the example of a snake bite, the use of anti-venom halts the spread of toxins whilst receiving antibiotics to impede infection. Even after the initial cause of the necrosis has been halted, the necrotic tissue will remain in the body. The body's immune response to apoptosis, which involves the automatic breaking down and recycling of cellular material, is not triggered by necrotic cell death due to the apoptotic pathway being disabled.
Another application of biogenic substances is in the synthesis of metallic nanoparticles. The current chemical and physical production methods for nanoparticles used are costly and produce toxic waste and pollutants in the environment. Additionally, the nanoparticles that are produced can be unstable and unfit for use in the body. Using plant-derived biogenic substances aims to create an environmentally-friendly and cost-effective production method. The biogenic phytochemicals used for these reduction reactions can be derived from plants in numerous ways, including a boiled leaf broth, biomass powder, whole plant immersion in solution, or fruit and vegetable juice extracts. C. annuum juices have been shown to produce Ag nanoparticles at room temperature when treated with silver ions and additionally deliver essential vitamins and amino acids when consumed, making them a potential nanomaterials agent. Another procedure is through the use of a different biogenic substance: the exudate of germinating seeds. When seeds are soaked, they passively release phytochemicals into the surrounding water, which after reaching equilibrium can be mixed with metal ions to synthesise metallic nanoparticles. M. sativa exudate in particular has had success in effectively producing Ag metallic particles, while L. culinaris is an effective reactant for manufacturing Au nanoparticles.
Sources: en.wikipedia.org
Muslims will then serve the favored four communities, while faithful Druze believers will be appointed as leaders. In his numerous epistles addressed to Christians, Bahā'-al-Dīn frequently refers to them as "saints" and "assemblies of saints". His writings also show a remarkable familiarity with the New Testament and Christian liturgy.
Aerobic exercise comprises innumerable forms. In general, it is performed at a moderate level of intensity over a relatively long period of time. For example, running a long distance at a moderate pace is an aerobic exercise, but sprinting is not. Playing singles tennis, with near-continuous motion, is generally considered aerobic activity, while activities with brief bursts of energetic movement within longer periods of casual movement may not be aerobic. Some sports are thus inherently "aerobic", while other aerobic exercises, such as fartlek training or aerobic dance classes, are designed specifically to improve aerobic capacity and fitness. It is most common for aerobic exercises to involve the leg muscles, primarily or exclusively. There are some exceptions. For example, rowing to distances of 2,000 meters or more is an aerobic sport that exercises several major muscle groups, including those of the legs, abdominals, chest, and arms.
Methionine synthase reductase, also known as MSR, is an enzyme in humans that is encoded by the M1T3R gene. It functions as the obligate reductase for methionine synthase and restores its cofactor to an active state allowing it to sustain folate and methionine metabolosis.
== DeSUMOylation == SUMO can be removed from its substrate, which is called deSUMOylation. Specific proteases mediate this procedure (SENP in human or Ulp1 and Ulp2 in yeast). In yeast, SMT3 encodes the SUMO protein, and SUMO E3 ligase attaches SUMO to target proteins. In cell cycle regulation, the base case is that SUMO ligation is constantly taking place, leading to polySUMOylation of eligible target proteins. This is countered by the SUMO protease Ulp2 which cleaves polySUMO groups, leaving the protein in a monoSUMOylated state. As shown in the figure, there is a feedback mechanism in which ULP2 maintains the monoSUMOylated state by passively and diligently cleaving SUMO such that the polySUMOylated state is never stabilized enough to be acted upon by downstream actors. This deSUMOylation is critical to prevent precocious advancement of the cell cycle as discussed in several studies.
Sources: en.wikipedia.org
Trump renewed his talk of annexing Greenland, an autonomous territory of the Kingdom of Denmark, with CNBC noting that this prompted more serious concerns in the wake of Maduro's capture. The US already operates a military base in Greenland, Pituffik Space Base, and Denmark has indicated its openness to a heightened US military presence there, but Trump has been uninterested in anything less than a full US takeover, noting "that's what I feel is psychologically needed for success. I think that ownership gives you a thing that you can't do with, you're talking about a lease or a treaty. Ownership gives you things and elements that you can't get from just signing a document" and "When we own it, we defend it. You don't defend leases the same way, you have to own it". Asked "Psychologically important to you or to the United States?", he said: "Psychologically important for me." Hours after the strikes Katie Miller, wife of White House Deputy Chief of Staff Stephen Miller, posted a picture of a Greenland in the colors of the American flag with the caption "SOON" on X, prompting a rebuke from Denmark's ambassador to the US that "we expect full respect" for Denmark's territorial integrity and the two countries, being close allies, should continue to work as such.
MHC Class II molecules are a class of major histocompatibility complex (MHC) molecules normally found only on professional antigen-presenting cells such as dendritic cells, macrophages, some endothelial cells, thymic epithelial cells, and B cells. These cells are important in initiating immune responses. Antigens presented by MHC class II molecules are exogenous, originating from extracellular proteins rather than cytosolic and endogenous sources like those presented by MHC class I. The loading of a MHC class II molecule occurs by phagocytosis. Extracellular proteins are endocytosed into a phagosome, which subsequently fuses with a lysosome to create a phagolysosome. Within the phagolysosome, lysosomal enzymes degrade the proteins into peptide fragments. These fragments are then loaded into the peptide-binding groove of the MHC class II molecule. Once loaded, the MHC class II-peptide complexes are transported to the plasma membrane via vesicular transport, where they present the antigens to the extracellular environment. In humans, the MHC class II protein complex is encoded by the human leukocyte antigen gene complex (HLA). Class II HLAs are composed of the classical HLA-DP, HLA-DQ, and HLA-DR and non-classical HLA-DM and HLA-DO MHC molecules.
E300 ascorbic acid (approved for use as a food additive in the UK, US Canada, Australia and New Zealand) E301 sodium ascorbate (approved for use as a food additive in the UK, US, Canada, Australia and New Zealand) E302 calcium ascorbate (approved for use as a food additive in the UK, US Canada, Australia and New Zealand) E303 potassium ascorbate (approved in Australia and New Zealand, but not in the UK, US or Canada) E304 fatty acid esters of ascorbic acid such as ascorbyl palmitate (approved for use as a food additive in the UK, US, Canada, Australia and New Zealand) The stereoisomers of Vitamin C have a similar effect in food despite their lack of efficacy in human scurvy. They include erythorbic acid and its sodium salt (E315, E316).
Sources: en.wikipedia.org
Selank is a synthetic peptide made of seven amino acids. It is modeled on tuftsin, a natural tetrapeptide, with an added three-residue tail. It is not a small-molecule drug.
It originates from research in Russia, associated with the Institute of Molecular Genetics of the Russian Academy of Sciences. The first descriptions date to the mid-1990s. Most published studies come from Russian laboratories.
No, Selank itself does not occur naturally. Its backbone is based on tuftsin, which is produced in the body, but the seven-residue version is a synthetic construct. It is supplied as a manufactured peptide.
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.