The short version of Regulatory peptide fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2025-08-27. Anything still debated is marked as such rather than presented as 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.
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.
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.
| 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 |
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.
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.
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.
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.
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.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
This can be applied to find the best substrates for proteolytic enzymes. The substrate is displayed on the bacterial cell surface between an affinity ligand and the scaffold, and the kinetics of substrate proteolysis is measured using FACS. Bacterial display can be used to find peptides which bind to specific cells e.g. breast cancer cells or stem cells. Displayed proteins are fluorescently tagged with GFP, so binding interactions between peptides and target cells can be seen by flow cytometry. Control samples are required in order to measure fluorescence levels in the absence of displayed peptides. Samples are also required which don’t contain displayed peptides, but contain mammalian cells and bacterial cells (including the scaffold). Vaccine delivery is a very common application of bacterial surface display. There are two types of live bacterial vaccines that can be made:
=== Trim weights in aircraft === Aircraft that contain depleted uranium trim weights for stabilizing wings and control surfaces (such as the Boeing 747–100) may contain between 652 and 1,059 pounds (296 and 480 kg) of DU. This application is controversial because the DU might enter the environment if the aircraft crashes. The metal can also oxidize to a fine powder in a fire. Its use has been phased out in many newer aircraft. Boeing and McDonnell-Douglas discontinued using DU counterweights in the 1980s. Depleted uranium was released during the crash of El Al Flight 1862 on 4 October 1992, in which 152 kilograms (335 lb) was lost, but a case study concluded that there was no evidence to link depleted uranium from the plane to any health problems. DU counterweights manufactured with cadmium plating are considered non-hazardous as long as the plating is intact.
Secretin receptor family (class B GPCR subfamily) consists of secretin receptors regulated by peptide hormones from the glucagon hormone family. In early classifications, adhesion G protein-coupled receptors were included as part of the secretin receptor family, but in some more recent classification systems they are considered a distinct family (see for example: GRAFS). The secretin-receptor family of GPCRs include vasoactive intestinal peptide receptors and receptors for secretin, calcitonin and parathyroid hormone/parathyroid hormone-related peptides. These receptors activate adenylyl cyclase and the phosphatidyl-inositol-calcium pathway. The receptors in this family have seven transmembrane helices, like rhodopsin-like GPCRs. However, there is no significant sequence identity between these two GPCR families and the secretin-receptor family has its own characteristic 7TM signature. The secretin-receptor family GPCRs exist in many animal species. Data mining with the Pfam signature has identified members in fungi, although due to their presumed non-hormonal function they are more commonly referred to as Adhesion G protein-coupled receptors, making the Adhesion subfamily the more basal group. Three distinct sub-families (B1-B3) are recognized.
Bully: Garrett Height: 6'0 Weight: 199 lb Victim(s): Nicholas and Eric Fighter: Michael Westbrook Height: 6'3 Weight: 212 lb Money earned by Bully: $3,000 Money earned by victim(s): $7,000 Original airing:
Sources: en.wikipedia.org
=== Etymology === Although according to the Oxford English Dictionary, the term "beriberi" comes from a Sinhalese phrase meaning "weak, weak" or "I cannot, I cannot", the word being duplicated for emphasis, the origin of the phrase is questionable. It has also been suggested to come from Hindi, Arabic, and a few other languages, with many meanings like "weakness", "sailor", and even "sheep". Such suggested origins were listed by Heinrich Botho Scheube, among others. Edward Vedder wrote in his book Beriberi (1913) that "it is impossible to definitely trace the origin of the word beriberi". The word berbere was used in writing at least as early as 1568 by Diogo do Couto, when he described the deficiency in India. Kakke (脚気), which is a Japanese synonym for thiamine deficiency, comes from the way "jiao qi" is pronounced in Japanese. "Jiao qi" is an old word used in Chinese medicine to describe beriberi. "Kakke" is supposed to have entered into the Japanese language sometime between the sixth and eighth centuries.
=== Editors === Francis Pharcellus Church (1859), editorial writer for the New York Sun and author of Yes, Virginia, There is a Santa Claus Horatio Sheafe Krans (1894), author and editor Simeon Strunsky (1900), literary editor of the New York Evening Post and editorial writer for The New York Times Lester Markel (1914), edited "Review of the Week", a section of The New York Times, which won the Special Awards and Citations Pulitzer Prize in 1953 Daniel Longwell (1922), co-founder and managing editor of Life Theodore M. Bernstein (1924), assistant managing editor of The New York Times Herbert Solow (1924), editor of Fortune Groff Conklin (1927), science fiction anthologist Emanuel Freedman (1931), foreign editor of The New York Times James Wechsler (1935), editorial page editor of the New York Post David Perlman (1939), former science editor of the San Francisco Chronicle Lester Bernstein (1940), former editor-in-chief of Newsweek Werner Wiskari (1941), international news editor of The New York Times Lucien Carr (1946), editor for United Press International Byron Dobell (1947), editor of American Heritage, Esquire; mentor to journalists Tom Wolfe, David Halberstam, and Mario Puzo Charles Peters (1949), founder and former editor-in-chief of The Washington Monthly Ashbel Green (1950), senior editor and vice president of Alfred A. Knopf Emile Capouya (1951), literary editor of The Nation 1969–1981 Robert Gottlieb (1952), editor of The New Yorker and president of Alfred A.
The Red Book, formally titled Nomenclature of Inorganic Chemistry, is a collection of recommendations on inorganic chemical nomenclature. It is published at irregular intervals, with the latest full edition published in 2005, in both paper and electronic versions.
Sources: en.wikipedia.org
Wrinkles deepen, and forehead frown lines can be seen even when not frowning. Telangiectasias (spider veins) are most commonly seen around the nose, cheeks, and chin. Skin becomes leathery, and laxity occurs. Solar lentigines (age spots) appear on the face and hands. Possibly pre-cancerous red and scaly spots (actinic keratoses) appear. Cutaneous malignancies In addition to the above symptoms, photoaging can also result in an orderly maturation of keratinocytes and an increase in the cell population of the dermis, where abundant, hyperplastic, elongated, and collapsed fibroblasts and inflammatory infiltrates are found. Photodamage can also be characterized as a disorganization of the collagen fibrils that constitute most of the connective tissue, and the accumulation of abnormal, amorphous, elastin-containing material, a condition known as actinic elastosis.
=== Triplexfpp === Triplexfpp is based on deep learning methods. This Python-based pipeline can help predict the most likely triplex-forming lncRNA. However since the lncRNA for training is limited, there is a long way to go before machine learning and deep learning methods can be applied.
== Medical uses == Methocarbamol is a muscle relaxant used to treat acute, painful musculoskeletal spasms in a variety of musculoskeletal conditions. However, there is limited and inconsistent published research on the medication's efficacy and safety in treating musculoskeletal conditions, primarily neck and back pain. Methocarbamol injection may have a beneficial effect in the control of the neuromuscular spasms of tetanus. It does not, however, replace the current treatment regimen. It is not useful in chronic neurological disorders, such as cerebral palsy or other dyskinesias. Currently, there is some suggestion that muscle relaxants may improve the symptoms of rheumatoid arthritis; however, there is insufficient data to prove its effectiveness or to answer concerns regarding optimal dosing, choice of muscle relaxant, adverse effects, and functional status.
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.
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.